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Amusan, Anuoluwapo. "Optimization of oil extraction procedures from animal tissue." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40832.
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Oil was extracted from chicken and pork fat discards by microwave assisted extraction and soxhlet extraction for comparison. Protease enzyme and pulsed electric field were used as a pretreatment prior to extraction by either soxhlet or microwave assisted extraction by hexane. Conditions for both the enzyme pretreatment and the microwave extraction were optimized for the extraction of the oils from the discards. The fat discards were pretreated with papain enzyme in a phosphate buffer solution (pH 7.0) and incubated at 45oC in a water bath and incubated at various time intervals (30 min, 1 h, 2 h and 3 h). Enzyme pretreatment at 2 h produced the highest oil yield increase of 20.1% when compared to the control samples (P=0.0003) in chicken samples and an oil yield increase of 16.6% in comparison to control samples (P=0.0179) in pork samples. There was a decrease in oil yield at 3 h and no significant difference in oil yield when compared to control in both chicken samples (P=0.217) and pork samples (P=1.0000). Optimization of microwave assisted process shows that microwave irradiation for 7.5 min produced the best oil yield and was the most effective in oil extraction from the animal discards. There was no significant difference in oil yield produced when the irradiation time was increased to 10 min, 12.5 min, and 15min. The results obtained from optimization of microwave assisted extraction were comparable to those obtained by soxhlet extraction for 3 hr. There were significant difference between oil yield obtained from both extraction methods (P=<0.05). There were no differences in the FAME profile when compared to the literature. Pulsed electric field pretreatments were carried out on pork samples at electric field strength of 2 kV cm-1, 4 kV cm-1, 6 kV cm-1. The oil yields obtained were compared to values obtained from control samples after extraction using microwave assisted extraction for 3 min. Pulsed electric field at 4 kV cm-1 produced an oil yield increasLes matières grasses des déchets associés au parage provenant des industries porcine et avicole ont été extraites par l’utilisation d’une extraction assistée par les microondes et par une méthode standard, la méthode Soxhlet. Deux prétraitements, l’hydrolyse enzymatique et le champ pulsé, ont été utilisés avant l’extraction à l’hexane des matières grasses. Les conditions d’application du prétraitement enzymatique et de l’extraction assistée par les microondes ont été optimisées pour maximiser l’extraction à partir des matières grasses rejetées par l’industrie. Les déchets gras ont été prétraités avec une protéase, la papaïne, dans un tampon phosphate (pH 7.0) et incubés à 45oC dans un bain-marie pour des intervalles de temps variés (30min, 1 h, 2 h et 3h). Les augmentations les plus importantes de l’extraction des matières grasses ont été obtenues avec le prétraitement enzymatique des échantillons de volaille (20.1%, P=0.0003) et de porc (16.6%, P=0.0179) pour une durée de 2 h lorsque comparé aux échantillons témoins. Une diminution du rendement de l’extraction a été notée lors du traitement enzymatique d’une durée de 3h sans que ces valeurs montrent des différences significatives avec les échantillons témoins de volaille (p=0.217) et de porc (P=1.000). L’optimisation du procédé d’extraction par microonde a montré que l’irradiation avec les microondes pendant 7.5 min a produit les meilleurs rendements d’extraction. Aucune différence significative n’a été retrouvée lorsque les échantillons ont été soumis à l’irradiation pour des temps accrus à 10 min, 12.5 min et 15 min. Les résultats obtenus pour l’optimisation de l’extraction assistée par les microondes sont comparables à ceux obtenus par l’extraction pendant 3 h avec la méthode Soxhlet. Des différences significatives de rendement en matières grasses ont été obtenues avec les deux méthodes d’extracti
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Schweizer, Amelia Lee. "Determination and assessment of procedures of the pour-through nutrient extraction procedure for bedding flats and plug trays." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-10312009-020402/.
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Cavins, Todd J. "Adaptation of the PourThru Nutrient Extraction Procedures to Greenhouse Crop Production." NCSU, 2002. http://www.lib.ncsu.edu/theses/available/etd-10312002-105020/.
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The purpose of this research was to adapt the PourThru nutrient extraction technique, which is the displacement of the bulk solution from the production container without a destructive harvest, to commercial greenhouse crop production. PourThru is a quick and easy nutrient sampling technique that is not laboratory oriented and can help prevent costly nutritional problems for greenhouse crop producers. Additionally, time domain reflectometry (TDR) was evaluated as an experimental tool to measure substrate moisture content, which may affect PourThru extraction. Time domain reflectometry is quick, non-destructive and has potential for use in automation of moisture content determination in greenhouse production. Previous PourThru research had focused on techniques for use on large nursery containers (≈ 3800 cm3) versus the smaller floriculture containers (≈ 1500 cm3) and no exact calibration of PourThru nutrient values to saturated media extract (SME) values, the current standard for nutrient testing, had been completed. Therefore, studies were implemented to examine the relationship of PourThru to SME, evaluate irrigation systems and timing effect on PourThru results as well as develop recommended influent and leachate volumes to ensure an unadulterated sample. Calibration curves were developed between PourThru and SME values and r2 values ranged from 0.91 to 0.99 for linear relationships. Irrigation systems did affect electrical conductivity (EC) values and alternative interpretive standard values were developed dependent upon irrigation system. Timing of the PourThru was important to ensure adequate leachate was collected for sample analysis and the amount of influent affected EC values and the amount of leachate collected. The use of TDR was effective in small containers (980.6 and 2177.5 cm3); however, care should be taken to match probe size to container size to ensure representative sampling. The largest limitation to TDR use was the bulk density of the substrate being analyzed. Approximately a 50 to 75% underestimation occurred when substrate bulk densities were below 1.2 g.cm-3, but material specific calibration improved TDR accuracy to within 4%.
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Ma, Hongwei. "A new strategy for the extraction of genomic DNA from various biological matrices." Thesis, University of Strathclyde, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366903.
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Sloan, Raymond. "Enzyme extraction and dye-affinity purification procedures applicable to commercial biomedical diagnostics." Thesis, Queen's University Belfast, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336738.
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Ferreira, Lage Sandra. "The neurotoxin β-N-methylamino-L-alanine (BMAA) : Sources, bioaccumulation and extraction procedures." Doctoral thesis, Stockholms universitet, Institutionen för ekologi, miljö och botanik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-132142.
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β-methylamino-L-alanine (BMAA) is a neurotoxin linked to neurodegeneration, which is manifested in the devastating human diseases amyotrophic lateral sclerosis, Alzheimer’s and Parkinson’s disease. This neurotoxin is known to be produced by almost all tested species within the cyanobacterial phylum including free living as well as the symbiotic strains. The global distribution of the BMAA producers ranges from a terrestrial ecosystem on the Island of Guam in the Pacific Ocean to an aquatic ecosystem in Northern Europe, the Baltic Sea, where annually massive surface blooms occur. BMAA had been shown to accumulate in the Baltic Sea food web, with highest levels in the bottom dwelling fish-species as well as in mollusks. One of the aims of this thesis was to test the bottom-dwelling bioaccumulation hypothesis by using a larger number of samples allowing a statistical evaluation. Hence, a large set of fish individuals from the lake Finjasjön, were caught and the BMAA concentrations in different tissues were related to the season of catching, fish gender, total weight and species. The results reveal that fish total weight and fish species were positively correlated with BMAA concentration in the fish brain. Therefore, significantly higher concentrations of BMAA in the brain were detected in plankti-benthivorous fish species and heavier (potentially older) individuals. Another goal was to investigate the potential production of BMAA by other phytoplankton organisms. Therefore, diatom cultures were investigated and confirmed to produce BMAA, even in higher concentrations than cyanobacteria. All diatom cultures studied during this thesis work were show to contain BMAA, as well as one dinoflagellate species. This might imply that the environmental spread of BMAA in aquatic ecosystems is even higher than previously thought. Earlier reports on the concentration of BMAA in different organisms have shown highly variable results and the methods used for quantification have been intensively discussed in the scientific community. In the most recent studies, liquid chromatography-tandem mass spectrometry (LC-MS/MS) has become the instrument of choice, due to its high sensitivity and selectivity. Even so, different studies show quite variable concentrations of BMAA. In this thesis, three of the most common BMAA extraction protocols were evaluated in order to find out if the extraction could be one of the sources of variability. It was found that the method involving precipitation of proteins using trichloroacetic acid gave the best performance, complying with all in-house validation criteria. However, extractions of diatom and cyanobacteria cultures with this validated method and quantified using LC-MS/MS still resulted in variable BMAA concentrations, which suggest that also biological reasons contribute to the discrepancies. The current knowledge on the environmental factors that can induce or reduce BMAA production is still limited. In cyanobacteria, production of BMAA was earlier shown to be negative correlated with nitrogen availability – both in laboratory cultures as well as in natural populations. Based on this observation, it was suggested that in unicellular non-diazotrophic cyanobacteria, BMAA might take part in nitrogen metabolism. In order to find out if BMAA has a similar role in diatoms, BMAA was added to two diatom species in culture, in concentrations corresponding to those earlier found in the diatoms. The results suggest that BMAA might induce a nitrogen starvation signal in diatoms, as was earlier observed in cyanobacteria. However, diatoms recover shortly by the extracellular presence of excreted ammonia. Thus, also in diatoms, BMAA might be involved in the nitrogen balance in the cell.At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.
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Björkesten, Johan. "Development and evaluation of procedures and reagents for extraction of proteins from dried blood spots for analysis using Proseek." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-219292.
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A method for extraction of proteins from dried blood spots (DBS) for analysis using Proseek is developed and evaluated. DBS, as sample format, possesses a number of desirable advantages over for example plasma samples. These advantages include for example minimal patient invasiveness, sampling simplicity and non regulated sample transportation. Highly reproducible quantitative detection of 92 proteins is demonstrated from a 1.2 mm in diameter DBS disk. The DBS inter spot analysis precision (7% coefficient of variance) is comparable to plasma inter assay precision (6% coefficient of variance). Coefficient of variance is the ratio between standard deviation to mean value for the analysed replicates. Proseek analysis of DBS could possibly reveal a unique opportunity to examine health related issues in extremely premature infants hopefully resulting in increased survival rates in the future.
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Batista, Saulo Hilton Botelho. "Evaluation of the use of different local hemostatics procedures to manage post extraction bleeding in patients under anticoagulation treatment." Universidade Federal do CearÃ, 2010. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=6328.
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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel SuperiorThe therapeutic use of Varfarin, the most common oral anticoagulant it is indicated in many cases, including the atrial fibrillation, cardiac valvular prostheses and venous trombolic disease. Many discussions still exist related to the suspension or not before tooth extraction. People who are for itâs suspension agree that it may increase the risk of hemorrhage, however the ones who prefer to maintain itâs use refer the high risk of tromboembolism. Due to the controversy related to the cronic use of oral anticoagulant before tooth extraction and what to use to control bleeding after extraction, we decided to perform a one center randomized clinical trial study to compare the effectiveness of the hemostasis using soaked gauze with tranexamic acid at 4,8% and plain gauze and the use of collagen sponge (HemosponÂ), using it inside the tooth socket after extraction. The sample was made of 84 surgical procedures performed in 38 patients who were under anticoagulant treatment and who needed at least one tooth extraction. The trial was divided in three groups regarding the method used to reach hemostasis after tooth extraction. In group I we used compression with soaked gauze with tranexamic acid at 4,8%; in group II we used collagen sponge (HemosponÂ) inside the socket while in group III we compressed the socket with dry gauze for 8 minutes. There were two cases of post surgical bleeding, being one from group I and one from group II. The data collected was evaluated thru SPSS 1.5 (Statistic Package of Social Science) program. All the statistical analysis performed were considered significantly when p was less than 5%. We used the Qui square X2 Test, Fisher Exact Test e Analysis of Variance (ANOVA) to verify the variables of the data. There was no statistically significant difference between the groups, related to bleeding (p>0,05). The compression with dry gauze and suture, compression with soaked gauze with trenaxamic acid at 4.8% and suture and the use of collagen sponge (HemosponÂ) in the tooth socket hold with suture showed similar efficacy to the control of post extraction bleeding in patients who are under anticoagulant treatment.
A terapÃutica com varfarina, o anticoagulante oral mais utilizado, està indicada em mÃltiplas situaÃÃes, incluindo a fibrilaÃÃo atrial, prÃteses valvulares cardÃacas e o tromboembolismo venoso. DiscussÃes ainda existem sobre a indicaÃÃo ou nÃo da sua interrupÃÃo prÃvia a realizaÃÃo de exodontias. Aqueles que defendem a parada de sua administraÃÃo baseiam tal decisÃo no risco aumentado de hemorragias, enquanto os que acreditam na manutenÃÃo da terapia ressaltam o risco de tromboembolismo. Em virtude das controvÃrsias acerca da realizaÃÃo de exodontias em pacientes que fazem uso crÃnico de anticoagulantes orais, alÃm da dÃvida de que mÃtodo empregar no controle do sangramento pÃs-exodontia, decidimos realizar um estudo do tipo ensaio clÃnico, unicÃntrico, randomizado com o objetivo de comparar a efetividade hemostÃtica local da compressÃo com gaze embebida ou nÃo em Ãcido tranexÃmico à 4,8% com o emprego da esponja de colÃgeno (HEMOSPONÂ) no interior do alvÃolo pÃs-exodontia. A amostra foi constituÃda por 84 procedimentos cirÃrgicos realizados em 38 pacientes sob terapia anticoagulante que necessitavam de pelo menos uma extraÃÃo dentÃria. A amostra foi dividida em trÃs grupos a depender do mÃtodo hemostÃtico local empregado para o controle do sangramento apÃs a extraÃÃo dentÃria. No grupo I utilizou-se a compressÃo com gaze embebida em Ãcido tranexÃmico a 4,8%; no grupo II introduziu-se no interior do alvÃolo uma esponja de colÃgeno (HemosponÂ); enquanto no grupo III, a compressÃo com gaze seca por 8 minutos foi o mÃtodo empregado. Em dois casos foi observado sangramento pÃs-operatÃrio sendo um paciente do grupo I e outro do grupo II. Os dados coletados foram consolidados e avaliados por meio do programa SPSS 15.0 (Statistic Package of Social Science). Todas as anÃlises estatÃsticas efetuadas foram consideradas significativas quando valor de p foi menor que 5%. Utilizou-se os testes Qui-Quadrado (XÂ), Teste Exato de Fisher e AnÃlise de VariÃncia (ANOVA) para verificar as diferenÃas entre as variÃveis. NÃo houve diferenÃa estatisticamente significante entre os grupos com relaÃÃo à ocorrÃncia de hemorragias (p-valor>0,05). A compressÃo com gaze seca associado à sutura, a compressÃo com gaze embebida com Ãcido tranexÃmico a 4,8% associada a sutura e o emprego da esponja de fibrina (HemosponÂ) intra-alveolar associado a sutura mostraram eficÃcia semelhante no controle do sangramento pÃs-exodontia em pacientes sob terapia anticoagulante.
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Sahlabadi, Mohammad. "A NOVEL BIOINSPIRED DESIGN FOR SURGICAL NEEDLES TO REDUCE TISSUE DAMAGE IN INTERVENTIONAL PROCEDURES." Diss., Temple University Libraries, 2018. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/508489.
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Mechanical EngineeringPh.D.
The needle-based procedures are usually considered minimally invasive. However, in insertion into soft tissues such as brain and liver, the tissue damage caused by needle insertion can be very significant. From the literature, it has been known that reduction in needle insertion and extraction forces as well as tissue deformation during the insertion results in less invasive procedure. This work aims to design and develop a new bioinspired design for surgical needles which reduce the insertion and extraction forces of the needle, and its damage to the tissue. Barbs in honeybee stinger decrease its insertion force significantly. Inspired by that finding, a new honeybee-inspired needle was designed and developed, and its insertion mechanics was studied. To study the insertion mechanics of honeybee-inspired needle, insertion tests into artificial and biological tissues were performed using both honeybee-inspired and conventional needles. The barb design parameters effects on needle forces were studied through multiple insertion and extraction tests into PVC gels. The design parameters values of the barbs were experimentally modified to further reduce the ultimate insertion and extraction forces of the needle. Bioinspired needle with modified barb design parameters values reduces the insertion force by 35%, and the extraction force by 20%. To show the relevance, the insertion tests into bovine liver and brain tissue were performed. Our results show that there was a 10-25% decrease in the insertion force for insertions into bovine brain, and a 35-45% reduction in the insertion force for insertions into the bovine liver using the proposed bioinspired needles. The bioinspired and conventional needles were manufactured in different scales and then used to study the size scale effect on our results. To do so, the insertion tests into tissue-mimicking PVC gels and liver tissues were performed. The results obtained for different sizes of the needle showed 25-46% decrease in the insertion force. The tissue deformations study was conducted to measure tissue deformation during the insertion using digital image correlation. The tissue deformation results showed 17% decrease in tissue deformation using barbed needles. A histological study was performed to accurately measure the damage caused by needle insertion. Our results showed 33% less tissue damage using bioinspired needles. The results of the histological study are in agreement with our hypothesis that reducing needle forces and tissue deformation lead to less invasive percutaneous procedures.
Temple University--Theses
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Davis, Derek Charles. "The applicability of environmental impact assessment (EIA) procedures to mineral extraction, waste disposal and land reclamation schemes in south Essex." Thesis, Queen Mary, University of London, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.409292.
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Grove, Alewyn Petrus. "Development of a finite element based nominal stress extraction procedure for fatigue analysis of welded structures." Diss., University of Pretoria, 2006. http://upetd.up.ac.za/thesis/available/etd-12182007-125836/.
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Cans, Pierre. "Contribution a l'identification des dynamiques de production des pristinamycines et a la mise au point de nouvelles procedures de fabrication." Toulouse, INSA, 1987. http://www.theses.fr/1987ISAT0019.
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Un calcul theorique ayant montre que la culture de aspergillus niger sur milieu solide d'amidon de manioc etait limitee par la disponibilite de l'eau dans le substrat, l'introduction de 20% d'un support lignocellulosique a forte capacite de retention d'eau a permis d'augmenter l'activite de l'eau du milieu et, ainsi, d'accelerer et ameliorer le processus fermentatif. L'extension de la notion de support a ensuite conduit a pratiquer des cultures de a. Niger sur un milieu liquide dissous absorbe sur une phase solide. Dans un tel systeme, l'activite de l'eau de la solution d'impregnation, la taille des particules du support et la quantite d'inoculum de spores ont ete les parametres importants de la croissance du champignon. Ce type de culture a permis d'utiliser des milieux liquides glucoses tres concentres (400 g/l) qui sont utilises pour la croissance en 40h. Une etude microcalorimetrique a mis en evidence l'existence d'une phase exothermique situee entre la germination et la croissance exponentielle
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Trávníčková, Jana. "Transport kovů v systému půda/rostlina. Porovnání metody aktivního a pasivního vzorkování (Technika difúzního gradientu v tenkém filmu)." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2011. http://www.nusl.cz/ntk/nusl-233341.
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The doctoral thesis deals with comparison between copper uptake by radish (Raphanus sativus L.) and concentration of copper measured by a DGT-device and concentration of copper obtained by extraction with generally used extraction agents (HNO3, NaNO3 and water). Plants were cultivated in pot experiments on a tested non-treated and gradually spiked soil. The amount of copper was determined in various part of radish (whole plant, above- and below-ground part) after mineralization in the APION mineralizer by ET – AAS. The highest concentration was in belowground part, especially in root tissues and sheel of root bulb. It confirms copper is associated with cell walls. The amount of copper taken by radish up does not pass beyond sanitary standards not even in spiked soils and consummation of radish is not unhealthy. Good correlations were found between copper concentration in radish and the amount of copper extracted with HNO3, NaNO3 and water and the amount found in soil solution. Results of extraction with HNO3 confirmed the amount of copper was stable in spiked soils during the pot experiments. The DGT experiments have shown that the rate of resupply from the solid phase to soil solution is constant during the deployment time. Whereas the release of copper decreases after 24 hours in natural soil. Copper added to soil in form of cupric ions is present in the different form after one month-equilibration than copper present in unspiked soils. The results obtained by DGT measurements were approximately up to two orders of magnitude lower than copper concentration obtained by leaching with sodium nitrate. The extraction with sodium nitrate does not provide true reflection of metal availability to plant root system and soil microorganism. High values of correlation coefficients (R2 > 0,9) were found between concentration of copper in radish plant and the concentration of copper in soil solution measured by DGT technique. Concentration of copper in soil solution was three times higher than concentration measured by DGT technique. Soil solution contains species of copper that are not measured by DGT technique and available to plants. Concentration of metals obtained by DGT measurements is more closely to real concentration of bioavailable forms of metal in soil. Therefore it is possible to recommend the DGT technique as a technique for determination of bioavailable forms of copper in soils.
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HEDSTRÖM, CORTINOVIS CLARA. "Potential mobility of Cd and Ni in salt marsh sediments colonized by Zostera noltii : A study on the comparison of three different sequential extraction procedures to assess of the effect of shellfish collectors in the Mira Estuary (Portugal)." Thesis, Umeå universitet, Kemiska institutionen, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-130491.
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Hamaali, Arkan Latif. "A Study of Selecting an Efficient Procedure for Intermittent Electrochemical Chloride Extraction." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for konstruksjonsteknikk, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-11563.
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In this eight specimens were prepared in laboratory. Four of the specimens were with w/cratio (0.4) and the other four specimens were with w/c ratio (0.5). All of the specimens were intentionally contaminated with 3% (by cement weight) of chlorides during the mixing process in order to study the effect of various parameters, like (current density, intermitting the current in different periods, and the w/c ratio), on the total efficiency of the ECE treatment. A titanium net, immersed in calcium hydroxide electrolyte solution, was used in this work, and the current densities were (0.7 and 1.0) A/m2 by steel surface. Two different current-on intervals (12 and 5) days were used as well, while the current-off interval was 2 day in all cases of treatment. The plexiglass-spacers, which used between the anode net and the concrete surface in order to reduce the acidification of the concrete surface, result in lower efficiency of the ECE in the adjacent concrete surface above it. Keeping the concrete surface immersed in the electrolyte solution during all the treatment’s period led to diffusing a considerable amount of chlorides in these areas out of the concrete. According to the overall results of the chloride measurement; the 12 days of current-on treatment was most efficient in the early stage of the intermittent treatment, while the 5 days of current-on treatment was most efficient in the advanced stages of the intermittent treatment. Therefore, it can be beneficial to apply the ECE with gradient current-on intervals that starts with long intervals and ends with short intervals. Due to the low current densities that used, the total duration of the treatment was rather long (90 days) and the ECE treatment was most efficient in the specimens that treated with 1.0 A/m2 by steel surface. The variation between the two types of w/c ratios that used in this work was low and therefore, the influence of the w/c ratio on the ECE’s efficiency was difficult to be noticed. At the end of the treatment, the rates of extracted chlorides were generally between (80 and86)% in all the specimens excepting two of them which had two parameters in common (current density 0.7 A/m2 and 5 days of current-on intervals). These two specimens gave worst result and only about 66% of chlorides were extracted at the end of the treatment.
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Sathish, Ashik. "Biodiesel Production from Mixed Culture Algae Via a Wet Lipid Extraction Procedure." DigitalCommons@USU, 2012. https://digitalcommons.usu.edu/etd/1372.
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With world crude oil reserves decreasing and energy prices continually increasing, interest in developing renewable alternatives to petroleum-based liquid fuels has increased. An alternative that has received consideration is the growth and harvest of microalgae for the production of biodiesel via extraction of the microalgal oil or lipids. However, costs related to the growth, harvesting and dewatering, and processing of algal biomass have limited commercial scale production of algal biodiesel. Coupling wastewater remediation to microalgal growth can lower costs associated with large scale growth of microalgae. Microalgae are capable of assimilating inorganic nitrogen and phosphorous from wastewater into the biomass. By harvesting the microalgal biomass these nutrients can be removed, thus remediating the wastewater. Standard methods of oil extraction require drying the harvested biomass, adding significant energetic cost to processing the algal biomass. Extracting algal lipids from wet microalgal biomass using traditional methods leads to drastic reductions in extraction efficiency, driving up processing costs. A wet lipid extraction procedure was developed that was capable of extracting 79% of the transesterifiable lipids from wet algal biomass (16% solids) without the use of organic solvents while using relatively mild conditions (90 °C and ambient pressures). Ultimately 77% of the extracted lipids were collected for biodiesel production. Furthermore, the procedure was capable of precipitating chlorophyll, allowing for the collection of algal lipids independently of chlorophyll. The capability of this procedure to extract lipids from wet algal biomass, to reduce chlorophyll contamination of the algal oil, and to generate feedstock material for the production of additional bio-products provides the basis for reducing scale-up costs associated with the production of algal biofuels and bioproducts.
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Laurentjoye, Mathieu. "Osteotomies mandibulaires virtuelles : acquisition, planification, modelisation et production d’un guide occlusal et condylien imprime en 3 dimensions. Mise en place d’une chaîne méthodologique de la faisabilité à la clinique." Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0372/document.
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Le but de ce travail était la mise en place d’une chaîne méthodologique de planification virtuelle d’une ostéotomie sagittale des branches mandibulaires (OSBM) et son transfert au bloc opératoire. Dans la première partie, les méthodes classiques de planification et de transfert sont exposées. Habituellement réalisées à partir de modèles en plâtre sur articulateur, la planification et la production de guides occlusaux chirurgicaux souffrent d’une imprécision potentiellement à l’origine de troubles fonctionnels temporo-‐mandibulaires. Le contrôle per-‐opératoire du condyle mandibulaire lors de l’OSBM est un élément de stabilité squelettique dont dépend la qualité du résultat fonctionnel. Une évaluation des pratiques professionnelles des chirurgiens maxillo-‐faciaux a été réalisée sur ce point. Une méthode de positionnement condylien utilisant un dispositif, moins fréquemment utilisée que la méthode empirique, est proposée comme présentant le meilleur rapport bénéfice/risque. Cette méthode a été reproduite virtuellement à travers les différents maillons de la chaîne méthodologique. Des techniques innovantes informatisées d’acquisition, de conception et modélisation, et d’impression en 3 dimensions ont été utilisées. Dans la seconde partie, la méthodologie de chacun des maillons de la chaîne a été présentée et évaluée, soit sur sujets cadavériques, soit sur patients. L’objectif était de démontrer la faisabilité de la chaîne. Le maillon « acquisition et extraction de surface » a mis en exergue le problème des artéfacts dus aux matériaux métalliques dentaires ou orthodontiques. Dans 90% des cas le maillage obtenu était satisfaisant, permettant de s’affranchir des modèles en plâtre. Le maillon « planification chirurgicale virtuelle » a montré une valorisation par rapport à la technique classique en terme de prévention des interférences des pièces osseuses déplacées. Le maillon « modélisation et impression du guide chirurgical » a décrit les étapes d’invention d’un guide de positionnement occlusal et condylien (OCPD : occlusal and condylar positionning device). Ses caractéristiques techniques, ses modalités de production par impression 3D ainsi que son utilisation peropératoire, ont été précisées. Enfin le maillon « évaluation de l’OCPD » a permis de montrer la faisabilité de la méthode et l’équivalence clinique, technique et biologique de ce dispositif médical sur mesure par rapport à ceux utilisés dans la méthode classique. Enfin le positionnement condylien obtenu grâce à ce dispositif a été évalué de manière préliminaire et comparé aux données de la littérature. Grâce à l’OCPD, nous avons montré la possibilité de transférer au bloc opératoire la planification virtuelle d’une OSBM contrôlant la position des condylesThe purpose of this work was the implementation of a methodological chain for bilateral sagittal split osteotomy (BSSO) virtual planning and its transfer in the operating room. In the first part of the work, usual methods for planning BSSO are exposed. Usually realized from plaster models on articulator, the planning and the occlusal surgical guides production are at risk of temporo-‐mandibular functional disorders. The quality of the functional result depends on the correct positioning of the mandibular condyle, considered as a skeletal stability element. An assessment of the maxillofacial surgeons practices was realized regarding intra-‐operative condyle positioning. Using a condylar positioning device (CPD),less frequently employed than the empirical method, meets an acceptable benefit/risk balance. This method was virtually reproduced through various steps of the methodological chain described. Computerized innovative techniques for three-‐dimensional acquisition, design and manufacturing were used. In the second part of the work, the methodology of each step of the chain was presented and estimated, either on cadaveric subjects, or on patients. The aim was to demonstrate the feasibility of the whole chain. The “acquisition and surface extraction” step pointed the issue of artefacts due to dental or orthodontic metallic devices. Ninety % of the obtained meshes were satisfactory, allowing not to use plaster models. The “virtual surgical planning” step allowed reproducing the usual method and showed great interest in bone interferences prevention. The “modelling and printing of the surgical guide” step described the stages of occlusal and condylar positioning device (OCPD) invention. Its technical characteristics, its methods of manufacturing by 3D printing, and its intraoperative use were specified. The step “OCPD evaluation” showed the method feasibility and the clinical, technical and biological equivalence of this custom-‐made medical device as compared to those used in the usual method. Finally the condylar position obtained with this device was estimated in a preliminary clinical study and compared with the literature. Thanks to the OCPD, we showed the possibility of transferring in the operating room an OSBM virtual planning controlling condyles position
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Dao, Steve Gia 1973. "Procedure for optimal D.C. parameter extraction for hot-carrier degradation model calibration and verification." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/47435.
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Gondim, Tamyris de Aquino. "Analytical Procedure Development paragraph Extraction and Pre - Iron Concentration in Production Water Samples Using Cloud Point Extraction and Atomic Absorption Spectrometry Flame." Universidade Federal do CearÃ, 2015. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=14630.
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CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel SuperiorProduced water from petroleum industry is characterized by their high salinity and its complex composition. Depending on its origin, the produced water may contain a variety of chemicals such as organic salts, aliphatic hydrocarbons, polycyclic aromatic hydrocarbons (HPA), potentially toxic metals and radioactive materials. Therefore, the disposal of these production waters can be considered a major problem for the oil industry, since the produced water must be characterized and treated before being discarded at sea. This characterization includes evaluating the concentration of inorganic elements; however, the determination of these elements is not a simple procedure because of the complexity of the sample matrix, which has high salinity causing scattering and suppression of analytical signal in spectrometric analysis. This work proposes a methodology to iron quantification in saline produced water from oil industry by flame atomic absorption spectrometry (FAAS) after cloud point extraction (EPN). The procedure is based on the cloud point extraction using PAN as complexing agent and Triton X-114 as surfactant. The parameters that can influence the CPE were studied and optimized using a Box-Behnken design in order to get the best conditions for iron extraction. The CPE has the advantage of being a simple, low cost, in accordance with the green chemistry, selective and preconcentration factor compatible with other traditional methods. The proposed method was validated by obtaining a limit of quantification of 0.010 mg L-1 and detection limit of 0.003 mg L-1. Linear response within 0,02 and 0,40 mg L-1 . The precision of the method was evaluated in terms of repeatability, obtaining a coefficient of variation of CVm 0.67 %. The accuracy of the method was assessed by recovery experiments of Fe fortification in three concentration levels that presented recovery of Rm 101.58 %. The method applied with satisfactory performance to determine iron production waters.
Ãguas de produÃÃo sÃo caracterizadas pela alta salinidade e sua composiÃÃo complexa. Dependendo da sua origem, as Ãguas de produÃÃo podem conter uma variedade de substÃncias quÃmicas, tais como sais orgÃnicos, hidrocarbonetos alifÃticos, hidrocarbonetos aromÃticos policÃclicos (HAP), metais potencialmente tÃxicos e materiais radioativos. Portanto, o descarte dessas Ãguas de produÃÃo pode ser considerado um grande problema para a indÃstria petrolÃfera, visto que as Ãguas de produÃÃo tÃm de ser caracterizadas e tratadas antes de serem rejeitadas no mar. Essa caracterizaÃÃo inclui a avaliaÃÃo da concentraÃÃo de elementos inorgÃnicos, entretanto, a determinaÃÃo desses elementos nÃo à um procedimento simples devido à complexidade da matriz da amostra, a qual possui alta salinidade provocando espalhamento e supressÃo de sinal analÃtico em anÃlises espectromÃtricas. No presente trabalho à proposto um procedimento para a determinaÃÃo ferro em Ãgua de produÃÃo derivada da indÃstria do petrÃleo por espectrometria de absorÃÃo atÃmica com chama (FAAS). O procedimento baseia-se na extraÃÃo em ponto nuvem (EPN) utilizando PAN como agente complexante e Triton X-114 como surfactante. Os parÃmetros que podem influenciar na EPN foram estudados e otimizados utilizando-se um planejamento Box-Behnken a fim de obter as melhores condiÃÃes para extraÃÃo de Ferro. A EPN tem como vantagens ser um mÃtodo simples, de baixo custo, em acordo com a quÃmica verde, seletivo e com fator de prÃ-concentraÃÃo compatÃvel com outros mÃtodos tradicionais. O mÃtodo proposto foi validado obtendo um limite de quantificaÃÃo de 0,010 mg L-1, limite de detecÃÃo 0,003 mg L-1. Resposta linear foi observada no intervalo de 0,02 a 0,40 mg L-1. A precisÃo do mÃtodo foi verificada em termos de repetitividade, obtendo um coeficiente mÃdio de variaÃÃo (CVm 0,67 %). A exatidÃo do mÃtodo foi averiguada por meio de ensaios de recuperaÃÃo, onde foi realizada a fortificaÃÃo em trÃs nÃveis de concentraÃÃo apresentando Rm 101,58 %. O mÃtodo foi aplicado com bons resultados para determinaÃÃo de ferro em Ãguas de produÃÃo
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Alderman, Lori A. "The evaluation and comparison of the extraction procedure toxicity test and the toxicity characteristic leaching procedure for the analysis of municipal wastewater sludges." Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/44103.
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A viable sludge management alternative is land application of waste sludge. However, it is necessary to implement efficient monitoring and analysis of land applied sludges in order to assess potential health risks associated with this means of disposal.
The State of Virginia is considering a proposal that requires land-applied wastewater sludges to undergo analysis by EPAâ s Toxicity Characteristic Leaching Procedure (TCLP) (EPA, 1986b) to determine if the sludge exhibits hazardous characteristics, which preclude land application as a management alternative. The method currently used for the analysis of hazardous wastes is the Extraction Procedure (EP) Toxicity Test. Both of these test methods analyze for trace organic chemicals and heavy metals. However, the TCLP is designed to analyze for volatile organic chemicals to a greater extent than the EP. Because of the added complexity and the current expense of the TCLP, the State is concerned that the TCLP may not be warranted for the analysis of trace organic chemicals in land-applied sludges.
This research was designed to compare the abilities of the EP and TCLP for the analysis of trace organic chemicals in wastewater sludges. Samples from three municipal wastewater treatment plants that utilize secondary biological treatment, aerobic digestion and land-apply waste sludge were evaluated by both EP and TCLP methods. Both tests utilize a weak acid extraction to remove organic chemicals from the wastewater sample. The weak acid extract was subjected to liquid-liquid extraction (EPA Method 625) to partition and concentrate the organic chemicals into methylene chloride; this methylene chloride extract was then subjected to GC and GC/MS for quantitative analysis and qualitative identification of targeted and nontargeted organic chemicals.
In order to assess recovery and extractability efficiencies of each test, surrogate standards were added prior to the test procedure. These standards were bromoform, 1-chlorooctane, DDT, ethylene dibromide (EDB, a volatile fungicide), fusarex (tetrachloronitrobenzene), and heptachlor. Control samples were run for both EP and TCLP, in addition to a sludge samples with no surrogates added.
Analysis indicated that both the TCLP and EP tests showed high variability for the recovery of the sludge surrogates. The recoveries of the surrogate standards were low and varied between zero and 30 percent depending on the standard and the matrix. Surrogate recoveries were evaluated with respect to various physical/ chemical properties of the individual standard, the sample site, and the test method utilized. Although the TCLP recovered the volatile surrogate standards only slightly better than the EP, there was no statistically significant difference between the TCLP and EP for the recovery of the non- and semi-volatile surrogate standards.
Specific trace organic chemicals identified in the sludges included dimethylpentanol, dichlorodimethoxybenzene, 4-methylphenol, and tetrabutylphenol. Other chemicals, such as contaminants and artifacts resulting from laboratory processing and background contamination in the reagents, were also identified in the blank control samples as well as the sludge samples.
Master of Science
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Lambert, Patricia. "Evaluation of the Chlorophyll/Fluorescence Sensor of the YSI Multiprobe: Comparison to an Acetone Extraction Procedure." Thesis, University of North Texas, 2001. https://digital.library.unt.edu/ark:/67531/metadc2794/.
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The purpose of this study was to examine the suitability of the YSI model 6600 Environmental Monitoring System (multiprobe) for long term deployment at a site in Lewisville Lake, Texas. Specifically, agreement between a laboratory extraction procedure and the multiprobe chlorophyll/fluorescence readings was examined. Preliminary studies involved determining the best method for disrupting algal cells prior to analysis and examining the precision and linearity of the acetone extraction procedure. Cell disruption by mortar and pestle grinding was preferable to bath sonication. Comparison of the chlorophyll/fluorescence readings from the multiprobe and the extraction procedure indicated that they were significantly correlated but temperature dependent.
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Diouf, Aissatou. "Effect of Organic Amendments on Heavy Metal Distribution and Uptake in Vegetable Gardens in Senegal." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/73036.
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The major constraints to food production in West Africa are related to the lack of suitable lands. Consequently, farmers incorporate organic amendments and wastewater to improve their yields. Within some limits, such wastes enhance soil fertility and can improve its physical properties. However, the advantages of using organic waste as fertilizer and soil amendment should be assessed with possible environmental and toxicological impacts due to the potential presence of heavy metals. The objective of this study was to assess the effect of organic amendments on heavy metal distribution in soils and vegetables in market gardens in Senegal. Organic amendments and soils samples were collected from four sites in eastern and southern Senegal. Samples were analyzed for physicochemical properties including particle size, total heavy metals, carbon content, nutrients, and pH. A sequential extraction procedure was conducted to determine heavy metal sinks. Results showed that sites were sandy in nature, low to medium in organic carbon content (8300 to 36600 mg kg-1), and had pH ranging from 5 to 7.9. The sequential extraction procedure showed that metals were distributed in the more stable soil fractions: Fe-Mn oxide, organic and residual. The highest soil metal concentrations in soils were found in Pikine and Rufisque sites. Plant samples were collected from these two sites and analyzed for total metal content. Results showed that all metal concentrations in soils, organic amendments, and vegetables were within the safe limits proposed by the World Health Organization, with the exception of Cd, Pb and Zn levels in vegetables.Master of Science
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Chestnutt, Sheryl A. "Comparison of the extraction procedure toxicity test (EP) and the toxicity characteristic leaching procedure (TCLP) for the analysis of trace organic compounds in land applied municipal wastewater sludges." Thesis, Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/44626.
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The current Environmental Protection Agency (EPA) method utilized for analysis of trace organic chemicals and heavy metals leached from solid waste is the Extraction Procedure (EP) Toxicity Test. Because of various operational problems and limitations of the EP, the EPA has developed and plans to implement the Toxicity Characteristic Leaching Procedure (TCLP), which is an expanded version of the EP capable of analyzing more organic components, in particular volatile organic chemicals.
The purpose of this research was to investigate and compare the ability of the EP and TCLP test procedures to quantitatively recover added surrogate standards (1,2-dibromoethane, bromoform, 1â chlorooctane, fusarex, heptachlor, and DDT) and also qualitatively identify and evaluate unknown trace organic chemicals in domestic wastewater sludges. In order to meet the research objectives established, three small (approximately 1 MGD or less) municipal wastewater treatment plants that land applied their sludges were analyzed.
Master of Science
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Purushothama, Shobha. "A Study of the Effect of the Extraction Procedure in the Analysis of Organic Compounds Adsorbed on Coal Ash." TopSCHOLAR®, 1996. http://digitalcommons.wku.edu/theses/817.
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The organic compounds found adsorbed on coal fly ash have been a cause for concern since the early days of the industrial revolution. A vast majority of the compounds reported as being adsorbed on the ash are polyaromatic hydrocarbons (PAHs). This study represents an attempt to evaluate the parameters involved in the extraction, detection and quantitation of these organic compounds. Though no definite conclusions could be reached as to the most efficient method of extraction, interesting results were obtained with regarding the choice of the solvent and the temperature programming on the GC/MS used for analysis. The solvent of choice appears to be methylene chloride. A slow heating rate appears to give better results as compared to one in which the components elute out in a short time.
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Ndiaye, Oumoule. "Impacts of Water, Extraction Procedure and Origin on Anthocyanins and Volatile Compositions of Hibiscus Extracts and Freeze-Dried Hibiscus." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/88756.
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There has been a lot of interest in Roselle (Hibiscus sabdariffa L.), called Bissap in Senegal, hibiscus recently because of consumer interest in nutraceutical products. However, beverages made from hibiscus have a short self-life due to anthocyanin and flavor degradation. The purpose of our study was first to assess the impacts of water, extraction procedure and origin on the anthocyanins of hibiscus extracts and secondly, to examine the impacts of freeze-drying on the anthocyanins and the volatiles compositions of hibiscus extracts. For the first experiment, a 2x3 factorial design was used with hibiscus calyces from Senegal and Egypt for the factor origin, distilled water and reformulated Dakar (Senegal) water for the second factor water, and then cold and hot extraction procedures were applied. For the second experiment, Senegalese hibiscus was extracted with hot and cold water and one part of each extract was freeze-dried. For both objectives, a ratio of 1:15 w/v (1 kilogram of calyces for 15 liters of water) were used. The time-temperature was 98°C / 30 min for hot and 22°C / 4 hours for cold extractions. The anthocyanins were determined using high performance liquid chromatography (HPLC). And the volatiles were measured using headspace-solid phase microextraction and gas chromatography-mass spectrometry (HS-SPME-GCMS). Origin and temperature as well as their interaction had significant effects on the anthocyanin contents, with respective p-values of 0.0036 and 0.0025 and 0.0002. Freeze-drying showed no effect on the anthocyanins in cold extracts. In contrast, a significant difference between the hot extract and its freeze-dried product was observed with a p-value of 0.0013. For the flavor compounds, the aroma profiles were different between cold and hot extracts and their instant powders. Globally the results of this study can help in the optimization when processing hibiscus derivatives.MSLFS
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Favorito, Jessica Elizabeth. "An Investigation into Selenium Geochemistry in Phosphate Mine Soils." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/77945.
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In the western United States, elevated selenium (Se) levels in soil have resulted in documented cases of ruminant fatalities. This is due to the ingestion of Se-hyperaccumulating vegetation growing on previously reclaimed phosphate mine soils. A field-scale analysis was first conducted to examine Se bioavailability to plants. Soil and plant samples were collected from transects from five study locations in Soda Springs, Idaho. Soils were analyzed for Se speciation and geochemical phases using a sequential extraction procedure (SEP). Additionally, speciation, SEP results, and Se bioavailability in the hyperaccumulator, western aster (Symphyotrichum ascendens (Lindl.)), were related using simple linear regression. Soil speciation and the validity of this SEP were then evaluated using synchrotron-sourced X-ray absorption fine structure (XAFS) spectroscopy for both whole and a sequence of extracted soils. Lastly, competitive adsorption of Se with two dissolved organic carbon (DOC) species, citric and salicylic acid, was examined on an amorphous iron oxide mineral surface.
A strong relationship was identified for western aster Se and the first two combined SEP fractions, water-soluble and PO43--extractable Se (R2 = 0.85; P = <0.0001). Results also indicated a strong relationship between selenate and water-soluble Se (R2 = 0.83; P = 0.0002). This suggests that water extracts could be useful Se bioavailability assessment tools in highly contaminated systems. XAFS analyses indicated that elemental and organic Se were the most predominant phases overall in whole soils. The dominant oxidized species present was selenite sorbed onto iron oxides and calcite. Critical SEP evaluations using XAFS also indicate that oxidized Se species were underestimated by the SEP and elemental Se was overestimated. In extracted soils, XAFS results indicated partial recovery of carbonate, iron oxide and organic Se occurred. Therefore, it is suggested that researchers exert caution when employing SEPs. Additionally, sorption analyses demonstrated the highly competitive behavior of citric acid with both selenite (pH 5-8) and selenate (pH 5-6). Little competition was observed in the presence of salicylic acid for both Se species. Competition and subsequent desorption of both sorbed species in the presence of citric acid suggest a possible mechanism for Se solubilization and bioavailability in seleniferous environments.Ph. D.
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Dardengo, Camila de Sousa. "Comparação tridimensional dos efeitos dentários de duas mecânicas para fechamento de espaço: estudo preliminar." Universidade do Estado do Rio de Janeiro, 2013. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=7222.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorAs más oclusões de Classe I com biprotrusão dentária são caracterizadas pela projeção dos incisivos superiores e inferiores e podem ser corrigidas com extrações de primeiros pré-molares, permitindo reposicionar os incisivos, usando como ancoragem os dentes posteriores. Esse trabalho teve como objetivo comparar, por meio de superposição de modelos tridimensionais, a movimentação de molares e de incisivos com duas técnicas para fechamento de espaços. Foram selecionados, tomografados (T0) e distribuídos, aleatoriamente em dois grupos, seis pacientes com indicação de exodontia de quatro primeiros pré-molares. No grupo 1 (n=3) foi feito o fechamento dos espaços das extrações em uma única etapa (fechamento em massa) e no grupo 2 (n=3), em duas etapas (distalização de caninos seguida da retração de incisivos). Após o completo fechamento dos espaços foi solicitada nova tomografia (T1). Os modelos tridimensionais em T0 e T1 para os dois grupos foram superpostos para descrever e quantificar a movimentação ocorrida nos primeiros molares. A retração de incisivos foi avaliada de maneira bidimensional. Os molares superiores e inferiores do grupo 1 sofreram movimentação mesial de translação, enquanto os do grupo 2, apresentaram deslocamento de coroa maior do que de ápice radicular, demonstrando movimento de inclinação mesial de coroa. Ao se comparar o movimento mesial dos molares entre os dois grupos, observou-se que no grupo 1 houve maior movimentação mesial da raiz mésio-vestibular dos molares superiores (p=0,009). No entanto, em ambos os grupos os molares superiores giraram sobre a raiz palatina. No arco inferior verificou-se maior movimento mesial de coroa para o grupo 2 (p=0,015). A análise da movimentação dos incisivos apresentou variações semelhantes para as medidas lineares e angulares dos incisivos superiores nos dois grupos. Já, para as medidas angulares dos incisivos inferiores, observou-se que o grupo 1 apresentou menor controle de torque. O tempo de tratamento de todos os pacientes da amostra foi superior a 30 meses, exceto um paciente que apresentou tempo de tratamento inferior a 24 meses. Pôde-se concluir que a perda de ancoragem ocorreu por movimento de translação no fechamento de espaços em massa, e por inclinação mesial no fechamento de espaços em duas etapas, para ambos os arcos. Parece haver maior movimentação mesial radicular nos molares superiores no fechamento em massa e maior movimento mesial de coroa dos molares inferiores para o fechamento em duas etapas. Sugere-se que não há diferença na retração dos incisivos superiores e maior retroinclinação dos incisivos inferiores no fechamento de espaços em duas etapas.
Class I malocclusions with dental biprotrusion are characterized by the projection of upper and lower incisors and can be corrected with extractions of four first premolars, allowing incisor retraction using the posterior teeth as anchorage. The purpose of this research was to compare the movement of molars and incisors, by superimpostions of three-dimensional models, with two space closure techniques. Six patients with indication for four first premolar extractions were selected, tomographed (T0) and randomly assigned to two groups. For Group 1 (n=3) premolar extraction space closure was performed in one-stage (en masse retraction) and for group 2 (n=3) in two stages (canine retraction followed by incisor retraction). After complete space closure, a new tomograph was taken (T1). The three-dimensional models, in T0 and T1, for both groups were superimposed to describe and quantify first molar movement. Incisor retraction was evaluated in two dimensions. The upper and lower molars in group 1 presented bodily mesial movement, while those in group 2, presented greater crown than root movement, demonstrating mesial crown tipping. When the amount of mesial molar movement was compared between the two groups, a greater mesial root movement was observed for upper molars in group 1 (p=0.009). However, in both groups the upper molars rotated aroung the palatal root. In the lower arch, a greater mesial crown movement was observed in group 2 (p=0.015). Incisor movement analysis presented similar variations for linear and angular measurements for upper incisors in both groups. In contrast, the angular measurements for the lower incisors demonstrated more torque control in group 2. The treatment time for all patients in the sample was greater than 30 months, with the exception of one patient, who presented treatment time smaller than 24 months. In conclusion, anchorage loss ocurred by bodily movement in en masse space closure and by mesial crown tipping in two-stage space closure, in both arches. In addition, there might be greater mesial root movement for upper molars in en masse space closure and greater mesial crown movement in two-stage space closure. It can also be suggested that there are no differences in upper incisor retraction and there is greater lower incisor uprighting in two-stage space closure.
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Pérez, Forero Fernando José. "Essays in structural macroeconometrics." Doctoral thesis, Universitat Pompeu Fabra, 2013. http://hdl.handle.net/10803/119323.
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This thesis is concerned with the structural estimation of macroeconomic models via Bayesian methods and the economic implications derived from its empirical output. The first chapter provides a general method for estimating structural VAR models. The second chapter applies the method previously developed and provides a measure of the monetary stance of the Federal Reserve for the last forty years. It uses a pool of instruments and taking into account recent practices named Unconventional Monetary Policies. Then it is shown how the monetary transmission mechanism has changed over time, focusing the attention in the period after the Great Recession. The third chapter develops a model of exchange rate determination with dispersed information and regime switches. It has the purpose of fitting the observed disagreement in survey data of Japan. The model does a good job in terms of fitting the observed data.Esta tesis trata sobre la estimación estructural de modelos macroeconómicos a través de métodos Bayesianos y las implicancias económicas derivadas de sus resultados. El primer capítulo proporciona un método general para la estimación de modelos VAR estructurales. El segundo capítulo aplica dicho método y proporciona una medida de la posición de política monetaria de la Reserva Federal para los últimos cuarenta años. Se utiliza una variedad de instrumentos y se tienen en cuenta las prácticas recientes denominadas políticas no convencionales. Se muestra cómo el mecanismo de transmisión de la política monetaria ha cambiado a través del tiempo, centrando la atención en el período posterior a la gran recesión. El tercer capítulo desarrolla un modelo de determinación del tipo de cambio con información dispersa y cambios de régimen, y tiene el propósito de capturar la dispersión observada en datos de encuestas de expectativas de Japón. El modelo realiza un buen trabajo en términos de ajuste de los datos.
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Marque, Étienne. "L’accès aux énergies fossiles en droit international économique." Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0118.
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Notre planète recèle dans sous-sol des gisements d’hydrocarbure, à l’origine depuis près d’un siècle, de la puissance de l’homme moderne. La présente étude porte sur les modalités juridiques d’extraction et d’appropriation de ces énergies fossiles. A l’état naturel, ces ressources n’ont pas d’existence juridique propre et leurs régimes suivent celui des territoires dans lesquels elles gisent. Aussi, pour que l’extraction des gisements puise avoir lieu, il convient d’abord d’identifier les titulaires des droits sur les territoires pétrolifères et prendre en compte non seulement la diversité de ces territoires mais également la diversité des acteurs et intérêts en présence. Les détenteurs primaires des droits d’accès aux ressources identifiés, pourront alors se déployer des contrats de prospection et d’exploitation des gisements, adaptées à l’ensemble des spécificités du secteur et des particularismes locaux, aux fins notamment d’une optimalisation de l’accès aux ressources fossilesOur planet contains underground fossil deposits powering the Modern man, since nearly a century. The present study deals with the legal issue regarding the extraction and appropriation of fossil fuels. In their natural state, these resources have no legal existence and their regimes follow the one of the territories in which they lie. Therefore, in order to extract the deposits, it is first necessary to identify the rights owners of the oil regions and to take into account not only the diversity of these territories but also the diversity of the actors and interests at stake. Once the primary access rights owners identified, deposits may be discovered and developed, through specific mining contracts, adapted to all the specific features of the sector and local particularities for the optimization of the access to fossil fuels
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SU, YU-NING, and 蘇育寧. "Comparison of Different Sequential Extraction Procedures for Heavy Metal Speciation." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/71578427664307864684.
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碩士國立聯合大學
環境與安全衛生工程學系碩士班
104
Atmospheric particle is an important indicator of air pollution. International Agency for Research on Cancer (IARC) has published that particulate matter is carcinogenic to humans (Group 1), and it is one of the main environmental factors causing cancers. The main chemical components of particulate matter are metals, carbon and water-soluble ions. The toxicity of heavy metals of particulate matter. Thus, this study investigated three different sequential extraction methods by testing three different samples including a reference material, fly ash and ambient particle. The results showed that heavy metals of fly ash mainly existed in Fe-Mn oxides, organics and residuals by both Rodriguez and Tessier extraction. Besides, most heavy metals of fly ash could be extracted by simulated gastric fluid. However, heavy metals of ambient particle extracted by Rodriguez mainly existed in exchangeable. On the contrary, most heavy metals of ambient particle extracted by Tessier existed in Fe-Mn oxides, organics and residuals. Then, Sr, Mn, Pb, Zn were mainly extracted by simulated gastric fluid.
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Kasselman, Graeme. "An evaluation of predictive environmental test procedures for sewage sludge." Diss., 2004. http://hdl.handle.net/2263/30565.
Full textAbstract:
This research project aimed at evaluating four internationally accepted leachate extraction tests to determine their applicability on sewage sludge samples. Furthermore, the present analytical method to determine the leachable fraction of sludge for compliance to South African sludge legislation was evaluated. Leaching tests are done on sludge samples to determine element mobility. This is important since land application of sewage sludge is an accepted and regulated sludge management practice. A literature survey was done to evaluate the mobility over time of metals originating from sludge-amended soils. Mobility is initially due to the organic content of the soil and after organic matter decomposition, it is dependant on the inorganic content. Mobile metals in sludge-amended soil can cause potential environmental risks like groundwater contamination and metal accumulation in soil. Metal accumulation can further lead to increased plant uptake of metals. To determine the partitioning or fractionation of metals found in sludge-amended soil, selective sequential extractions and single extractions can be used. Since South African sludge legislation specifies a single extraction procedure, four were selected for comparative studies. The selected procedures were the USA Environmental Protection Agency (EPA) Toxicity Characteristic Leaching Procedure (TCLP) the Australian Standard Bottle leaching Test (AS 4439.3) the Nederlands Normalisatie-Insitiuut availability test (NEN 7341) and the Deutches Institut für Normung water leachability test (DIN 38 414-S4). A variation of the TCLP is specified for use in South Africa. Three sewage sludge sample lots were collected. The first consisted of 24 sub-samples that were collected from 24 different wastewater treatment works on the East Rand. Both leachable (TCLP) and total (aqua regia) extraction was done on these samples for Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Zn, Se, B and Fe. A relationship between the leachable and total extractions was found for Co and Pb but could not be tested by literature values due to a variation in the sample preparation. The TCLP leachates were also analysed by Atomic Absorption and Inductively Coupled Plasma techniques to compare the applicability of the two. It was found that both techniques are acceptable for leachate analysis. The second sample lot collected from a single wastewater treatment plant was used to determine the leachable effect of the difference between the South African adapted TCLP and the USA EPA procedure as well as the NEN procedure. The EPA specifies all samples be extracted on an “as is” basis while the South African adaptation specifies dry samples. It was found that no element was comparative between dry and wet sample for both extraction procedures. It was observed that wet extractions yield generally higher values than dry extractions. A third sample lot was collected two months after the second sample lot at the same wastewater treatment works. It was used to compare the four extraction procedures. From this it was found that the DIN yielded the highest results for the specified elements. This procedure could not be recommended since the experimental difficulties and the duration of the test make it an unsuitable regulatory compliance tests protocol.Dissertation (MSc (Environmental Technology))--University of Pretoria, 2006.
Chemical Engineering
unrestricted
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Tseng, Yuan-Cheng, and 曾元騁. "Applying XSLT Techniques to Information Extraction Procedures of Power Tool Ontology." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/m24u49.
Full textAbstract:
碩士國立臺灣科技大學
機械工程系
94
To develop a mechanical product, engineers always need to pay attentions to design requirements and safety rules. The design considerations cover mechanism structure, electrical control, power source, manipulation, safety limitations, performance etc. Power Tool products are designed to make people easy to carry out. There would have different force output to meet the needs of different workplaces. Light-weight and high-power are two mainstream demands of function improvements. During the product life cycle, design engineers have the strong pressure to seek helpful information from diverse knowledge sources, including patents, engineering documents and professional books. Effective approaches to collect, filter and search information are the most challenging research issues to relive the document classification and knowledge extraction problems. This paper describes the procedures of knowledge extraction based on IT technology in general. Power Tool field is acted as the case study example to demonstrate the XML-related solutions. Our experimental work of Power Tool Knowledge Summarizing System is based on ontology framework suggested by Stanford’s Protégé project. Domain experts can annotate the patents and make good use of the classification tree derived form our ontology work. Our knowledge samples were carefully investigated and classified with the help of reference base of Power Tool Ontology. Our web-based experiment system can interactively response some simple queries to produce knowledge-routes report to make ‘document search and compare’ task easier. Next, the ontology can be converted completely to XML document format to cooperate with XSL Transformation techniques via online web publishing framework. Our system also integrates Power Tool glossaries to extend the breadth of domain knowledge. With the interactions of knowledge workers, our system can provide a summary report for their concept requests. Acted as a traveler's map, the summary report reveals the valuable information of inner knowledge hidden in patent papers. The proposed report also gives a guideline or technical suggestions integrated from other sources to conceive key design concepts.
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Silva, Mariana de Medeiros Campos Guerreiro e. "Alveolar extraction socket behaviour to alloplastic regenerative procedures: a comparative study." Master's thesis, 2019. http://hdl.handle.net/10451/41491.
Full textAbstract:
Aim: To compare clinical, and volumetric alterations of post extraction sockets with and without bone regeneration with Adbone®BCP on a socket preservation type of
regeneration.
Materials and Methods: Participants were assigned to one of two groups, at surgery day, having 16 anterior teeth divided equally into two groups. Bone regeneration was tested
by application of a biphasic calcium phosphate synthetic bone graft (Adbone®BCP) while natural healing was the control group. Clinical evaluation included intra-oral photographs and
an alginate impression. 3D examination consisted in extra-oral scanning of the obtained gypsum casts to generate 3D STL files. A comparison between initial and final buccolingual
dimensions was formed using CloudCompareV2 (version 2.6.1 [GPL software], 2019),measuring initial and final dimensions of both groups in 5 different sites (loss at 2, 3, 4, 5, 6
mm measured from coronal to apical of the extraction socket). Follow-up appointments were performed at days 7, 14 and 3 months postoperative.
Results: For the t-test, there was a significantly higher ridge dimensions loss on the control group, p=0.029, 0.045 and 0.041 for the first three measurements, respectively.
Given these p-values being < 0.05, there are significant differences regarding the loss between
the 2 groups, hence confirming the H1.
Discussion: There were differences between the test and control groups on the first three measurements (H2, H3, H4) given that tissue modelling is a rather rapid process. However, the
measurements situated apically on the alveolus, had p-values > 0.05, indicating that, given the short follow-up, the subsequent woven bone remodelling may take years to be completed and
thus had not happened yet.
Conclusion: Sockets grafted with Adbone®BCP suffered a reduced loss of volume on the alveolar socket contour, thus being effective on preserving the alveolar ridge.As extrações dentárias são um dos procedimentos mais comuns no ramo da medicina dentária, levando a mudanças significativas no rebordo edêntulo, dificultando o correto e satisfatório posicionamento de implantes, podendo assim comprometer o resultado das reabilitações protéticas. A extração dentária envolve um trauma mecânico nos tecidos moles, no ligamento periodontal e no osso do processo alveolar, levando a uma resposta inflamatória que recruta células hematopoiéticas e mesenquimais no local. Após uma extração, o processo de cicatrização inicia-se com hemorragia e seguinte formação de um coágulo, sendo substituído por tecido de granulação. Em seguida, forma-se uma matriz provisória de tecido conjuntivo, dando início à fase proliferativa onde há uma incorporação de vasos e células formadoras de osso dentro da matriz provisória. Ao fim do primeiro mês após extração, verifica-se o preenchimento do alvéolo com osso imaturo que será progressivamente substituído por osso lamelar e medular. O término do processo de cicatrização é clinicamente observado pelo encerramento, primário ou secundário, do alvéolo com tecido mole epitelizado e radiográfico pelo preenchimento ósseo do alvéolo. Consequentemente, este processo levará a alterações dimensionais no rebordo edêntulo. Embora se verifique alterações dimensionais até ao primeiro ano após extração, são durante os primeiros 3 meses que a perda óssea e tecidular é mais acentuada. Esta perda é influenciada por diversos fatores como as variações biológicas dos indivíduos, o tamanho do alvéolo pós-extracional e a extensão do trauma provocado durante a extração. Esta bem descrito na literatura que, após uma extração dentária, o rebordo edêntulo move-se em direção ao longo eixo do osso basal. A forma do maxilar parece retornar à forma em que estava antes do desenvolvimento do processo alveolar durante a erupção dentária. A falta de um estímulo funcional nas paredes ósseas e a necessidade de ajuste dos tecidos para se adaptar à geometria da crista na ausência de dentes podem explicar esta modificação. Dadas estas alterações dimensionais, a reabilitação destes espaços edêntulo fica comprometida, influenciando tanto o resultado estético como funcional. De forma a tentar prevenir estas complicações, muitos estudos mostraram os efeitos do uso de enxerto de diferentes biomateriais e diferentes técnicas e respetivos benefícios na regeneração óssea. As primeiras investigações concentraram-se no uso apenas de membranas regenerativas. Entretanto, pesquisas com enxertos ósseos em defeitos periodontais levaram os pesquisadores a explorar a utilidade das membranas em combinação com enxertos ósseos. Hoje em dia, a regeneração óssea guiada é geralmente realizada como um procedimento de combinação envolvendo membranas e um substituto ósseo de suporte. Alguns investigadores empregaram aloenxertos desmineralizados, maleáveis, rapidamente reabsorvidos e supostamente osteoindutores, enquanto outros utilizaram enxertos mineralizados, mais rígidos e osteocondutores. No entanto, não está claro qual material é mais eficaz para esta indicação clínica, já que estas técnicas incluem a colocação de diferentes materiais de enxerto, como autoenxertos ósseos, xenoenxertos, aloenxertos, combinados com membranas reabsorvíveis ou não reabsorvíveis e, mais recentemente, materiais bioativos, como L-PRF (leucócitos e fibrinas ricas em plaquetas). Um autoenxerto envolve a utilização de osso obtido do mesmo indivíduo que recebe o enxerto, enquanto que um aloenxerto é derivado de seres humanos que é colhido de outro indivíduo que recebe o enxerto, como por exemplo de cadáveres. Os xenoenxertos são enxertos ósseos de uma espécie diferente da humana, como os bovinos, são usados como uma matriz calcificada. Os aloplásticos podem ser feitos de hidroxiapatite, um mineral ósseo natural, fosfato tricálcico ou uma combinação de ambos. Os enxertos à base de fatores de crescimento são produzidos utilizando tecnologia de ADN recombinante, consistindo em fatores de crescimento humanos ou morfogénicos. Os substitutos de enxerto ósseo a base de cerâmica envolvem cerâmicas, isoladamente ou em combinação com outro material, como sulfato de cálcio, vidro bioativo e Fosfato de Cálcio. Contudo, a literatura não é clara relativamente ao material mais eficaz para as técnicas de regeneração alveolar. Um dos materiais mais estudados, o xenoenxerto, apresenta resultados benéficos com a sua utilização. Contudo, este material tem uma taxa de reabsorção lenta, levando a presença de partículas residuais que poderão interferir com a normal cicatrização alveolar bem como influenciar a qualidade do osso regenerado. Por outro lado, o uso de materiais aloplásticos de osteocondução também visa minimizar as alterações dimensionais que advém após extração. Adbone®BCP é um material de enxerto ósseo totalmente bifásico feito de 75% de hidroxiapatite (HAp) e 25% de fosfato tricálcico betafosfato (β-TCP). Deste modo, parece ter todas as propriedades necessárias para minimizar as mudanças que ocorrem em alvéolos pós-extracionais, tanto a nível ósseo como dos tecidos moles, conduzindo a uma menor reabsorção da tabua óssea vestibular e menor colapso tecidual. O objetivo deste estudo é comparar as alterações clínicas e volumétricas de alvéolos pós-extracionais com e sem regeneração óssea com Adbone®BCP. Materiais e Métodos: 11 participantes foram inseridos de acordo com os critérios de inclusão e exclusão, sendo designados para um dos dois grupos, no dia da cirurgia, com 16 dentes anteriores divididos igualmente em ambos os grupos. A regeneração óssea foi testada pela aplicação de enxerto ósseo sintético de Fosfato de Cálcio bifásico (Adbone®BCP) comparando-a com o grupo de controlo, a cicatrização natural. A avaliação clínica incluiu fotografias intra-orais e uma impressão em alginato. O exame 3D consistiu em leitura extra-oral dos modelos em gesso obtidos para gerar arquivos 3D STL e usando o CloudCompare v2 (versão 2.6.1 [GPL software], 2019), formando uma comparação entre as dimensões bucolinguais inicial e final dos tecidos duros e moles. Para tal, os ficheiros STL foram sobrepostos, escolhendo sete pontos em comum entre ambos para uma maior correspondência. Em seguida, traçou-se uma reta do ponto mais vestibular ao ponto mais palatino da raiz. Por fim, traçaram-se 5 retas, de 2 mm em 2 mm, a unir os dois ficheiros podendo avaliar as alterações dimensionais bucolinguais, em 5 regiões diferentes desde um ponto coronal e um mais apical. As consultas de acompanhamento foram realizadas nos dias 7, 14 e 3 meses de pós-operatório. Resultados: Foram medidas as dimensões iniciais e finais de ambos os grupos em 5 locais diferentes (perda de 2, 3, 4, 5, 6 mm, medidos de mais coronal para mais apical no alvéolo). Para o teste t, houve uma perda significativamente maior no grupo controle, com valores de p=0,029, 0,045 e 0,041 para as três primeiras medições, respetivamente. A nossa hipótese nula corresponde a que não há diferenças significativas na perda dimensional entre os dois grupos. Considerando-se que esses p-valores são < 0,05, existem diferenças significativas em relação a perda entre os dois grupos, confirmando, assim, a nossa hipótese testada. Discussão: Dados os resultados apresentados, existem diferenças estatisticamente significativas entre os grupos teste e controle nas três primeiras medições (H2, H3, H4), dado que a modelação tecidual e um processo bastante rápido. No entanto, as duas últimas medições, sendo estas mais apicais no alvéolo, apresentaram p-valores > 0,05. Deste modo, especula-se que, dado o curto período de acompanhamento, o remodelamento ósseo subsequente, sendo um processo um pouco mais lento, pode levar anos para ser concluído, logo ainda não serem visíveis tais alterações. Conclusao: Podemos concluir que existem diferenças estatisticamente significantes entre os alvéolos do grupo teste, regenerados com Adbone®BCP em comparação com a cicatrização de alvéolos do grupo de controlo. No entanto, há um número limitado de estudos sobre este enxerto ósseo, expondo assim a necessidade de mais ensaios clínicos randomizados avaliando o efeito do enxerto ósseo sintético Fosfato de Cálcio bifásico na regeneração óssea. Devido ao tamanho da amostra e curto período de acompanhamento, não é possível aplicar à população em geral.
34
Lin, Wen-Ting. "Systematic data preprocess procedures and factor extraction of multiple phenotypes for one-color microarray." 2004. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-1607200415331300.
Full text
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Zheng, Kuang-Zhe, and 鄭光喆. "Evaluation of Different Single and Sequential Extraction Procedures of Soils Contaminated by Heavy Metals." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/75027821447777326858.
Full textAbstract:
碩士中興大學
土壤環境科學系所
95
With industrial development and technical advance, some of the heavy metals used in artificial activities enter soil and cause contamination by improper handling. The most common method to determinate heavy metals in polluted soils is chemical extraction with different reagents. Chemical extractions includes single extractions and sequential extractions. Single extraction procedures extract heavy metals in soil by only one step, are usually time-saving, with easier process, and they can choose reagents for different purposes. Single extraction is suitable for differentiate mobility and bio-availability of heavy metals. Sequential extraction procedures extract different forms of heavy metals step by step, but they are time-consuming and with complicate process. However, sequential extraction procedures provide complete informations of different heavy metals forms in soil. It is possible to evaluate short-term and long-term impact of heavy metals against environment by sequential extraction results. Recently, Taiwan conforms aqua regia digestion to regulate the control standard of heavy metal content in soil. However, this method cannot directly reflect the threat to environment by heavy metals. There are two objectives for this study. One is to compare the results of BCR and Tessier sequential extraction applying on six contaminated soils with different heavy metals content to understand the fractionations of the heavy metals. The other purpose is to apply seven single extraction procedures including H2O, 0.1M CaCl2, 0.11M HOAc, 0.005M DTPA, 0.05M EDTA, 0.1M HCl, 0.12M HNO3 and XRF detection on 30 samples with different heavy metals content, to compare the results from single extractions and aqua regia digestion and to evaluate the practicability of single extractions replacing aqua regia digestion by double sampling design. Results of sequential extractions show that most of cadmium exists in exchangeable form than other heavy metals. In soils with low heavy metal concentration, most of copper and zinc are residual or reducible. In soils with high heavy metal concentration,most of copper and zinc would distribute in exchangeable form. Most of nickel and lead distribute in reducible or oxidisable form. Aqua regia digestion would overestimate the impact. chromium only distribute in reducible, oxidisable, and residual form. Few of chromium exist in exchangeable form, and it is harmless to the environment. Two sequential extractions lead to different results because of variation in methods. BCR procedure is an ideal method in terms of operation. Amont of heavy metals extracted by different single extraction reagent is in the following order: 0.1M HCl≥ 0.12M HNO3＞0.05M EDTA＞0.005M DTPA＞0.11M HOAc＞0.1M CaCl2＞＞H2O. 0.1M HCl extraction shows significant regression relationship between aqua regia digestion of Cd and Pb in these 30 samples. While results of 0.05M EDTA extraction show good regression relationship between aqua regia digestion of Cd, Cu and Pb. XRF detection shows the best regression relationship between aqua regia digestion in Cr, Ni, and Zn. It also shows significant regression relationship with aqua regia digestion of Cu and Pb. Applying double sampling to single extractions and aqua regia digestion shows 0.1M HCl can replace aqua regia digestion in Cd and Pb contaminated soils, XRF detection can replace aqua regia digestion in Cr, Cu, Ni or Zn contaminated soils. Analytical outlay can be saved and sample amount can be increased by applying two methods on specific polluted samples.
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Lin, Wen-Ting, and 林雯婷. "Systematic data preprocess procedures and factor extraction of multiple phenotypes for one-color microarray." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/22547434483964753647.
Full textAbstract:
碩士國立臺灣大學
工業工程學研究所
92
Microarrays are widely used to monitor gene expressions to yield information for genomes. Though there are many methods and mechanisms proposed to extract information from microarray data, the preprocess of raw expression data determine the accuracy and reliability of the extracted information. The first objective of this research is to implement a systematic procedure to preprocess the raw intensity reading. The proposed data preprocess procedure has 3 steps: rectification of intensity reading, signal normalization and bad spots screening. The rectification of intensity uses coefficient of variation (CV) to assess the consistencies of mean intensity and median intensity from raw intensity readings to decide which one to employ and then test the correlations between foreground intensity and background intensity to correct background intensity effects. Signal normalization transforms the rectified data to remove the chip-to-chip brightness variation and contrast variation by logarithm transformation, median subtraction and deviation division. After signal normalization, the hypothesis T-test is used to screen out bad expressions in replicated spots. More recently, microarrays have been conducted not only to relate genes with one phenotype, but also inquire relations between gene expression levels and multiple phenotypes. The second objective of this research is to apply Factor Analysis (FA) to extraction of the underlying co-regulating and independent factors of the multiple phenotypes. And then the treated factors can be taken as an individual phenotype for testing differentially expressed genes. Both of the objectives are to prepare experimental readings for accurate, effective biological information mining procedure. Finally, a real case of microarray experiment investigating gene expressions in 24 human blood samples with 19 phenotypes is provided to demonstrate and test the proposed preprocessing procedures.
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Zablocki, Heather Lynn. "The effect of the transpalatal arch on anchorage in extraction treatment a thesis submitted in partial fulfillment ... for the degree of Master of Science in Orthodontics ... /." 2005. http://catalog.hathitrust.org/api/volumes/oclc/67878281.html.
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Liu, Yen-Chun, and 劉彥均. "Long-term Stabilization Assessment of MSWI Bottom Ash by Using Sequential Extraction Procedures and Leaching Tests." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/36698570924835465804.
Full textAbstract:
碩士國立臺灣大學
環境工程學研究所
92
This study mainly examines the environmental effect of bottom ash from MSW incinerator by means of some different leaching tests along with simulated acid rain. The objectives also try to estimate the leaching potential of heavy metal in environment during a long period and to establish the fundamental data for risk assessment of the utilization of bottom ash; furthermore, to find a suitable stabilizer in order to promote the reuse of bottom ash. A mass transfer mathematical model is presented to predict quantity and quality of leachate from short-term column leaching test. Samples used here contain high amounts of Cu, which range from 5300 to 6600 mg per kg bottom ash. As time goes by, the amount of Cu leaches are twice more than that of any other metals in column test, and may reach up to a ratio 15% of its total mass. According to the stabilization test, Na2S reacts best in processing, which may reduce a large quantity of leachate by about 85－97%. Results of sequential extraction procedures show that 1% Cu is exchangeable, fraction bounded to carbonate accounts for 10%, fraction bounded to Fe-Mn oxides accounts for 34－44%, fraction bounded to organic matters/sulfide accounts for 10－20%, and the remaining 30% is residual. Good agreement was obtained by comparing model simulation with data of laboratory column leaching tests. This model can provide us an insight into factors that influence the physicochemical reaction and transport of leachate from bottom ash.
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Law, Ka Kiu Natalie. "Comparison of standard operating procedures used for the detection of opioids in blood." Thesis, 2020. https://hdl.handle.net/2144/41289.
Full textAbstract:
In forensic toxicology, opioids are frequently associated with drug abuse or drug-related death cases. An optimal method for use in the identification and quantification of opioids in a complex blood matrix is of paramount importance. Along with the ability to identify and quantitate opioids, this method should be accurate, sensitive, and selective. The application of sample pre-treatment and solid-phase extraction are common to purify and concentrate the target analytes before analyzing with liquid chromatography-tandem mass spectrometry.
The purpose of this study was to compare the performance of two standard operating procedures, adopted by the Massachusetts State Police Crime Laboratory Toxicology and the Biomedical Forensic Sciences– Toxicology Laboratory at Boston University School of Medicine, for detecting opioids in blood. A total of eight drugs were analyzed: 6-monoacetylmorphine, codeine, fentanyl, hydrocodone, morphine, norhydrocodone, oxycodone, and oxymorphone. Comparison was performed using the parameters studied as part of method validation, including calibration model, bias, precision, carryover, interferences, ionization suppression/enhancement, and recovery.
The results indicated that the method from Massachusetts State Police provided a better performance with between-run precision, interferences from matrix and other commonly encountered drugs, matrix effect at high concentration (250 ng/mL) and matrix recovery. Meanwhile, the method from Biomedical Forensic Sciences showed less bias, within-run precision, and matrix effect at low concentrations. Carryover and internal standard interference were comparable in both standard operating procedures. The calibration models were adjusted by altering the selection of regression model for improved quantification method performance. The volume of solvents, sample matrix, as well as time, were taken into consideration in accessing the overall performance of identification and quantitation. Both procedures were comparable yet the one from Massachusetts State Police was more beneficial in identifying the target analytes with greater sensitivity and selectivity and the one from Biomedical Forensic Sciences was more economical and efficient.
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Fang, Yen-Fei, and 方彥霏. "Study on Constructing Digital Evidence Forensics Standard Operating Procedures for Mobile Device - Extraction and Analysis of Digital Evidence on Smartphone." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/qrh62j.
Full textAbstract:
碩士國立宜蘭大學
多媒體網路通訊數位學習碩士在職專班
104
As Internet technology improves, mobile communications protocols mature and intelligent diversification and the popularity of mobile phones, change the habits of people using their cell phones, cell phone is no longer a traditional phone, smart phone, you can use communications software to communicate, surf the Web page associated with the transaction and storage of personal information ( Such as photos, notes, etc ), It's like computer action. Convenience of mobile phones, making it dependent on deepening, even those tools of crime, smart phone as the computer there are a lot of electromagnetic records, these records are digital evidence forensic value. In view of this, traditional methods of forensic equipment and will not be enough to gather digital evidence in the mobile phone. About digital evidence, and selection and use of forensic tools, is the main professional and examiner must have basic knowledge. Digital evidence collection, analysis, extraction process, you must use the standard digital forensics process in order to enhance its credibility and effectiveness. According to the scholars of this study by Professor I-Lon Lin 's Digital Evidence Forensics Standard Operating Procedure (DEFSOP), To constructing Digital Evidence Forensics Standard Operating Procedure for Mobile Device (DEFSOP For Mobile Device ). With the ISO 27037:2012 and ISO 27041:2015 analysis than to verify DEFSOP Rigorous and availability through the example DEFSOP For Mobile Device integrity and effectiveness. Mobile phone forensics operations, data extraction has some software tools can be used, under the multiple tools of interaction uses, extract the necessary evidence is not a problem, more difficult question is how to properly manage all these digital evidence, its maximum effectiveness. This study selected forensics tool for Android provides the ADB and the Cellebrite UFED through digital evidence forensics software extraction, classification and identification of data availability and validity of cross-analysis, comparison of reducing crime facts. The results of this study contribute: First, this study suggests that the Digital Evidence Forensics Standard Operating Procedure for Mobile Device (DEFSOP For Mobile Device) prototype, and three real cases to prove the four stages theory concepts, phases of preparation, action and reporting, provides event investigation and forensics officers followed standard operating procedures. Second, this study used forensic tools ADB and UFED , Through the comparative analysis of the advantages and disadvantages, operation and presentation of results, provide event investigation forensic tools reference you can follow. Three, an event-handling standards, this paper studies the international funding ISO 27041:2015 and use Cellebrite UFED Forensic tool test for China's first research master's thesis.
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Xu, Chen. "Optimized procedures for extractioin, purification and characterization of exopolymeric substances (eps) from two bacteria (sagittula stellata and pseudomonas fluorescens biovar ii) with relevance to the study of actinide binding in aquatic environments." 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2566.
Full textAbstract:
The extracellular polymeric substances (EPS) of marine bacterium Sagittula stellata
and soil bacterium Pseudomonas fluorescens Biovar II, were extracted by six methods
referred to the bibliography, efficacies of which were compared based on the EPS yield,
composition as well as cell disturbance. Purification methods on these EPS were also
improved, which proved to be more cost-effective and involve less interference from
broth, compared to previous methods. Size exclusion chromatography (SEC) proved to
be a useful tool, providing the “fingerprints” of the EPS extracted by different methods
or after each purification step. Studies of the EPS production and composition at
different growth stages provided abundant information and a basis for further in-depth
studies. Results from SEC demonstrated that bacterial EPS had a constant molecular
weight distribution all through the life but with various polymers in different proportions.
Three fractions were successfully isolated by a combination of SEC and anion exchange
chromatography for “non-attched” EPS produced by Pseudomonas flurorescens Biovar
II. Protein turned out to be a major component of EPS in their native states, which was mixed with the broth material and couldn’t be recognized previously. The EPS harvested
at the optimal time of the bacterial life was purified according to the improved method
and was more enriched in polysaccharides, with small amounts of proteins, giving the
molecules amphiphilic properties. In addition, simultaneous determination of neutral
sugars and uronic acids by GC-EI-MS provided more information on the
monosaccharide composition of the exopolysaccharides. Isoelectric focusing (IEF)
spectra of the bacterial EPS spiked with Pu/Th, and Pu-enriched Rocky Flats
Environmental Technology Site (RFETS) soil organic colloid spiked with Th showed
similar activity distributions of both actinides along the pH gradient, with the activities
of both actinides focusing on the low pH region. Characterizations of this Pu-enriched
IEF extract from RFETS soil by spectrophotometric methods and ATR-FTIR indicated
the co-presence of lipids, proteins and polysaccharides, in contrast to the bacterial EPS,
which showed a simpler composition. This suggests that Th/Pu binding to organic
macromolecules is more determined by the availability of binding functional groups
rather than the exact specific compounds.
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Ping, Jun-Jia, and 平峻嘉. "Effects of four different pretreatments on the leaching of Cu of municipal solid waste incinerator bottom ashes by using sequential extraction procedures." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/03267664573367984278.
Full textAbstract:
碩士國立中興大學
土壤環境科學系所
101
In Taiwan, large quantities of municipal solid wastes incinerator (MSWI)bottom ash generated and subsequent disposal of bottom ash from the incineration of municipal solid wastes have presented a significant problem. Recycling of MSWI bottom ash is a topic of growing importance for field of waste management. The application of bottom ash as the road pavement is widely used around the world. However, the content of Cu is relatively high in MSWI bottom ash, and it has a high leaching potential. This study mainly examines the effects of four different agents (Na2S, Na3PO4, PDTC and EDTA) pretreatments on the leaching of Cu of MSWI bottom ashes( 0.1–2 mm) fraction by using sequential extraction procedures. Results of sequential extraction procedures of untreated bottom ash show that 0.70% Cu is exchangeable, fraction bounded to carbonate accounts for 9.49%, fraction bounded to Fe-Mn oxides accounts for 11.4%, fraction bounded to organic matters/sulfide accounts for 26.9%, and the remaining 51.5% is residual. Through the Na2S pretreatment test, carbonate and Fe-Mn oxide fractions of Cu in MSWI bottom ash was transferred to organic matters/sulfide fraction. After Na3PO4 pretreatment test, that carbonate and organic matters fractions reduce and increase residual fraction.The results indicate that the immobilization efficiency of PDTC in treating with bottom ash is higher than Na2S and Na3PO4. The immobilization efficiencie of 0.2 % APDC pretreatment for 1day is over 97%. Immobilization of four agents pretreatments for 1day are more efficiency than short-time pretreatments. According to the extraction results of Cu extracted from MSWI bottom ash by 0.2M EDTA, extraction efficiencies of Cu of MSWI bottom ash were 20%. EDTA extraction could decrease the content of Cu, lower impact of Cu to the environment, and make the bottom ash mor environment friendly.
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Rai, Anooja. "Optimization and validation of a novel direct-lysis differential extraction procedure." Thesis, 2018. https://hdl.handle.net/2144/33006.
Full textAbstract:
Forensic analysis of DNA from sexual assault kits is a laborious process. These samples may be a mixture of sperm and male or female epithelial cells (E-cells). Generally, it is the sperm cells that are of greatest forensic value. Since its introduction in 1985 by Gill, Jefferys and Warrett, differential extraction has remained an essential pre-PCR extraction procedure adopted by most forensic laboratories for the preferential lysis of E-cells and isolation of sperm cells/male fraction prior to DNA profiling.
The differential extraction procedure operates based on the packaging of DNA in these two types of cells. The E cells are first lysed by sodium dodecyl sulfate (SDS) and Proteinase K which leaves the sperm cells intact. The mixture is centrifuged leaving E-cell DNA in the supernatant and sperm cells in the pellet. After several wash steps to remove residual E cell DNA, the sperm fraction is then subjected to lysis using SDS, proteinase K, and dithiothreitol (DTT). DTT reduces the disulfide bonds present in the sperm nucleus, thereby releasing sperm cell DNA.
The traditional Gill method of differential extraction, while proven to be highly effective in providing two separate fractions for a simplified interpretation of profiles, is a labor intensive and time-consuming process, requiring approximately six hours of an analyst’s concentration. In a casework scenario where an evidence sample is of a higher E cell concentration compared to sperm cells, it is inevitable to obtain mixture profiles that becomes more difficult to interpret. To mitigate carryover from the female fraction, the sperm cell fraction is usually subjected to multiple wash steps. Furthermore, the resulting fractions must be subjected to additional pre-PCR DNA purification procedures to remove PCR inhibitors such as SDS and Proteinase K which result in varying degrees on DNA loss.
Progress has been made over the years to introduce methods that allow for PCR-ready lysates without additional purification steps, often referred to as direct lysis methods. However, none have been proven to be viable options for use in sexual assault samples.
Our laboratory has developed a novel differential extraction procedure that is not only time-efficient and less laborious but also utilizes a direct-lysis procedure requiring no further pre-PCR purification for most samples. The novel procedure uses ZyGEM, which contains the thermophilic EA1 protease proven to effectively digest biological samples and produce PCR-ready lysates suitable for downstream nucleic acid amplification, thereby minimizing DNA loss. The procedure uses a multi-enzymatic approach and utilizes the different optimal activity temperatures of the enzymes to perform most of the process in a DNA extraction lab thermocycler, requiring only a single centrifugation for the usual separation of the E-cell fraction and no subsequent washing steps for the sperm cell fraction.
It has the potential to be a rapid, robust procedure that can be easily implemented in any forensic laboratory. This thesis will describe the procedure and report progress in the procedure optimization.2019-10-24T00:00:00Z
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Fu, Tz-Yu, and 傅子瑜. "An Accurate and Efficient Procedure for Schottky Barrier Height Extraction." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/60094448324726378077.
Full textAbstract:
碩士國立交通大學
電子研究所
102
As the scaling of the semiconductor fabrication process, the contact resistance in semiconductor devices becomes larger due to the smaller contact area, and the total driving current is degraded. How to reduce the contact resistance is an urgent issue for the continued scaling. Contact resistance is highly dependent on the Schottky barrier height (SBH) and the substrate doping concentration, so they can be lowered by adjusting these two parameters. Several studies have been proposed that the SBH can be lowered by some specific fabrication processes, for example ion implantations and thermal annealing, and those literatures reported the effective SBHs. However, these SBHs are extracted by the thermionic emission (TE) model, and it is not adequate for extracting the actual SBH. For the devices after specific fabrication process, the electric field near the semiconductor surface may be intensively increased, and the conducting mechanism may be no longer dominated by the TE model. For the high electrical field, the field emission (FE) model should be considered into the conducting mechanism. Without extracting the actual SBH, the effect of the specific fabrication process cannot be correctly discussed and applied. In this thesis, we setup a procedure to extract the SBH considering thermionic emission, field emission, image-force barrier lowering (IFBL) model and parasitic resistance thoroughly. The validity of the proposed procedure is verified and confirmed by technology CAD tool. Different SBHs and different substrate doping profiles have been discussed in the simulation work. Furthermore, the Schottky junctions on different semiconductor materials and the effects of ion implantations are studied, and the validity of extracting the exact low SBHs is discussed at last. In the simulation work, the difference of the IFBL models between the real case and the simulating tool is explored. The IFBL model in the simulation tool is too simple to fit the real Schottky junction. In the simulation of different substrate doping concentrations, the current-voltage characteristics at reverse bias are discussed. The slope in the log(J)-V raises as the concentration increases due to the severe IFBL effect. In the simulation of non-uniformly doped profiles, it is observed that the increasing of the surface doping concentration does not lower the actual SBH but induce severe IFBL effect. In the experiment, the validity of extracting the SBHs on various semiconductor materials including silicon carbide, germanium, and silicon, by the proposed procedure is verified. Furthermore, the effect of carbon ion implantation on the SBH of NiSi/Si contact is discussed. The extracted SBH and doping concentration show that the carbon ion implantation does not change the SBH but simply increases the effective carrier concentration. The validity of the exact low barrier height extraction is verified through the case of PtSi/Si Schottky junction. The temperature dependence of the SBH is observed at low temperature, and it is believed that the make-up of the surface states is changed and results in Fermi-level pinning at different energy levels. Finally, the effect of BF2+ ion implantation on the Schottky junction is discussed. In comparison with the simulation results, it is believed that the increasing boron ions enhance the IFBL effect and the fluorine ions have the ability to repair the surface states. This thesis proposes an efficiency and accurate procedure for the SBH extraction. It only takes about tens of seconds, and it is not necessary to cope with the measured data artificially. The effect of the specific fabrication process on the Schottky junctions can be correctly discussed and applied.
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"Standardized Sample Extraction Procedure for TCLP Testing of PV Modules." Master's thesis, 2017. http://hdl.handle.net/2286/R.I.45544.
Full textAbstract:
abstract: Solar photovoltaic (PV) deployment has grown at unprecedented rates since the early 2000s. As the global PV market increases, so will the volume of decommissioned PV panels. Growing PV panel waste presents a new environmental challenge, but also unprecedented opportunities to create value and pursue new economic avenues. Currently, in the United States, there are no regulations for governing the recycling of solar panels and the recycling process varies by the manufacturer. To bring in PV specific recycling regulations, whether the PV panels are toxic to the landfills, is to be determined. Per existing EPA regulations, PV panels are categorized as general waste and are subjected to a toxicity characterization leaching procedure (TCLP) to determine if it contains any toxic metals that can possibly leach into the landfill. In this thesis, a standardized procedure is developed for extracting samples from an end of life PV module. A literature review of the existing regulations in Europe and other countries is done. The sample extraction procedure is tested on a crystalline Si module to validate the method. The extracted samples are sent to an independent TCLP testing lab and the results are obtained. Image processing technique developed at ASU PRL is used to detect the particle size in a broken module and the size of samples sent is confirmed to follow the regulation.Dissertation/Thesis
Masters Thesis Engineering 2017
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Lu, Shin-Shang, and 呂星學. "The Extraction and Application for Procedural and Non-procedural Knowledge in Software Development Standards." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/74094952123880494608.
Full textAbstract:
碩士國防管理學院
國防資訊研究所
91
The technology changes with each passing day. It is necessary of an information organization to make their business with information to level their service quality up and avoid the loss of investment. And it is the primary process to apply the common standards on making business with information. Therefore, it can make the organization speed up the interchange the data inside and outside it to get the goal of common information, knowledge sharing and reusing. For the purpose of losing the cost of development, to lead to the common software development standard in the development processes for the information organization can reduce some needless risks. But, the common software development standard in international will evolve continuously by following the development of software engineering technology. In order to follow up the changes in the international, the organization will renew their software development standards. Besides, the cost of manpower and money is a heavy loading. Therefore, it is a very important thing that how to find the methods for saving their cost when leading a standard to origin workflow. When leading to the software development, the knowing deviation of individual domain knowledge causes the loss of time and the resource. The research uses the concept of ontology, and extracts the procedural knowledge and non-procedural knowledge in the standard. Moreover, we take the definition of pictorial isomorphism to inference the model of standard evaluating and the evaluating value from organizational workflow to software development standards. We wish it could help the information organization to short the time for leading standard and avoid the risks.
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Roberts, Ashleigh. "Optimization of a novel temperature controlled differential extraction procedure for aged sample analysis." Thesis, 2019. https://hdl.handle.net/2144/38690.
Full textAbstract:
There is a documented backlog of sexual assault samples in the United States. Of the many efforts made to reduce this backlog, efficient sample testing is among the most sought-after solutions. The Cotton lab at Boston University has developed a temperature controlled direct-lysis differential extraction protocol that has demonstrated efficient separation of spermatozoic and epithelial cell (e-cell) deoxyribonucleic acid (DNA) from fresh liquid samples. Here, efforts to adapt the protocol for use with dried and aged samples were examined.
Varying ratios of epithelial cell to sperm cells from a semen stock were pipetted onto substrates and allowed to age at room temperature for various lengths of time, ranging from 0 to 20 weeks. Modifications were then made to the Cotton lab’s protocol in an effort to optimize DNA yield without compromising the quality of resultant profiles. These modifications focused on the traditional use of spin-baskets and performing lysis on the substrate itself, as opposed to the flow through of traditional spin-basket differential extraction.
It was determined that ~95% of the spermatozoic DNA was retained by the substrate. Therefore, efforts were made to adapt the differential extraction protocol to be used directly on a substrate without the use of a spin-basket. It was determined that incubation of the substrate for one hour in water at room temperature prior to enzymatic extraction was beneficial to the percentage of sample recovery.
The modified Cotton lab temperature controlled differential extraction (TCDE) protocol was used to extract the epithelial cell and spermatozoic DNA from mixed-sample substrates after aging. Quantitative polymerase chain reaction (qPCR) was performed and the percent DNA recovery was determined. Epithelial cell DNA recovery declined from approximately 85% to 50% as aging progressed. However, spermatozoic DNA recovery remained stable at approximately 80% on average.
The resulting DNA profiles indicated that efficient separation of e-cells and sperm cells was achieved even after 20 weeks of aging. In instances where carry-over was detected, the carry-over signal was minimal, reaching a maximum of approximately 10% of the major contributor. Profiles were also analyzed to determine the degree of degradation of epithelial cell DNA and spermatozoic DNA over time. While some degree of degradation was observed after 20 weeks of aging, the probative quality of the profiles was preserved.
A representative group of aged samples was successfully extracted using a modified Cotton lab TCDE protocol. Profiles generated from these samples yielded single-source profiles or mixed profiles with a readily distinguishable major contributor. The results from the adapted protocol are encouraging for future use in the analysis of sexual assault evidence and the reduction of the sexual assault DNA backlog.
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Teng, Jui-yuan, and 鄧瑞元. "Study of the water-rock interaction in Tsengwenshi groundwater system using sequential extraction procedure." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/93661123330895190828.
Full textAbstract:
碩士國立中正大學
應用地球物理研究所
100
The heavy metals in groundwater seriously risk the human wealth, agriculture and the aquaculture, especially, if the water is the major source of daily use. Generally, in spite of anthropogenic source, the heavy metals in groundwater are released during water-rock interaction. However, there are many mineral phases being capable of releasing heavy metals. It would need a sequential extraction procedure to identify the source mineral phase in the aquifer. In addition, the geochemical reactions after the release of heavy metals are also important to modify the concentrations. In this study, the rare earth elements are used to be a natural tracer for this purpose. The study area, Tsengwenshi watershed in southern Taiwan, is an alluvial fan with all kinds of land uses and is notorious of arsenic contamination. The groundwaters sampled in this study show that arsenic is enriched in deep aquifer (depth>150m), which is composed of sediments deposited in the last glacial period (18 ka). Based on this conceptual model, the results of BCR sequential extraction procedure are categorized into shallow aquifer (depth<150m) and deep aquifer; and, the averages of heavy metals in two groups can be subsequently obtained to take account of extensive water-rock interaction in the groundwater system. The results show that arsenic and other heavy metals are mostly binding with Fe-Mn oxides. To compare the ratios between deep and shallow aquifers for all heavy metals, the pattern of groundwaters does not show the similar type with those of extracted phases from soils. It is believed that the released heavy metals were strongly modified by the geochemical reactions during the transportation in the groundwater system. In addition, the analysis results of the rare earth elements demonstrates that almost all groundwaters with high arsenic do not have Ce negative anomaly; and, on the contrary, those with low arsenic are generally characterized by strong negative anomaly. Generally, the Ce negative anomaly is a prominent indicator of oxidation reaction even though the groundwataers are very negative in redox state in the present. However, the relationship between Ce negative anomaly and arsenic is deserved to be evaluated in more detail.
49
Selbach, Pedro Alberto. "Optimization of a DNA extraction procedure for phylogenetic probe analysis of soil microbial communities." 1998. http://catalog.hathitrust.org/api/volumes/oclc/40688292.html.
Full text
50
Hsu, Kuei-Chiu, and 許桂秋. "Leaching Characteristics of Heavy Metals and Dioxin from Different Fly Ashes Using Sequential Extraction Procedure." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/05404369541609736203.
Full textAbstract:
碩士國立中央大學
環境工程研究所碩士在職專班
96
The fly ashes generated from incineration and metallurgical processes have been classified as a hazardous waste. In this study, sequential extraction procedure, TCLP and aqua regia extraction were used to explore chemical bondings and heavy metals in fly ashes generated from different steel industries and municipal waste incinerators (MWI). The potential impact of heavy metals leached in different leaching processes on the environment was investigated. In addition, the effect of acidic agents on total TEQ of dioxin in the collected ash samples was investigated by analysis of PCDD/F contents in residues collected from each fraction of sequential extraction. The results indicate that different chemical bondings and leaching characteristics of collected ash samples were observed and relied on steel-making materials, types of steel industries, types of steel-making furnaces, and operating parameters. Cadmium was mainly leached out from the first three steps (water-soluble, ion-exchangeable, and hydroxides and carbonates fractions) (Plant A: 93.6%, Plant B: 43.1%, Plant C: 70.8%, Plant D: 66.5%) and should be noticed during treatment due to its high mobility. The bonding structure of leached lead was performed differently based on the basic characteristics of ash samples. The results of heavy metals obtained from TCLP showed that the leached cadmium concentrations of collected ashes were 41.0, 6.84 and 23.7 mg/L, respectively, for Plant A, B, and C. These concentrations all exceeded the regulated standard. The leached lead concentrations for Plants A, B, C, and D were, respectively, 165, 83.2, 7.92, 9.83 mg/L, which were all over the regulated standard as well. The distributions of 17 toxic PCDD/Fs extracted from residue using sequential extraction procedure were found no difference in first five different extraction fractions (water-soluble, ion-exchangeable, hydroxides and carbonates, amorphous Fe-Mn oxides and crystal Fe oxides), and their concentrations were all below the regulated standard (1.0 ng I-TEQ/g). The highest concentrations of dioxin in the residue were found at the 6th extraction step（sulfide fraction）and this demonstrated the sufficient ability to leach a large amount of PCDD/Fs by using strong oxidants and acids at the sulfide fraction.