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Morcom, Andrea R. "PH responsive polymers for controlled release of liposomal contents." Thesis, Aston University, 2004. http://publications.aston.ac.uk/9658/.
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SOUZA, RODRIGO FERNANDES M. DE. "CHEMICAL PROCESSING OF SULFIDE CONCENTRATES WITH HIGH AND LOW COPPER CONTENTS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2016. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=33315@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO<br>COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR<br>CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO<br>PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO<br>Concentrado minerais sulfetados são uma importante fonte de matérias-primas nos processos de extração de metais não-ferrosos. No que diz respeito ao cobre, estes são usualmente processados segundo um fluxograma contemplando as etapas de ustulação, fusão mática, conversão e refino. Todavia, algumas características dos concentrados podem limitar a sua aceitação nas plantas de processamento tais como: baixo teor de cobre assim como a presença de elementos ditos deletérios, como, por exemplo, o flúor e seus efeitos corrosivos sobre materiais refratários após a transformação e ácido fluorídrico; ainda que o material possua um teor do metal de interesse elevado. Dentro desse contexto, o presente trabalho tem por objetivo avaliar o processamento químico de concentrados sulfetados de cobre com essas características a fim de entender o seu comportamento nos processos de ustulação, visando à identificação de condições que minimizem os efeitos danosos do flúor, no caso de concentrados de alto, assim como determinar uma janela operacional que possibilite a obtenção seletiva de CuSO4, no caso de concentrados de baixo teor. Para atender a esses objetivos, foi levado a efeito um estudo teórico incluindo uma breve revisão da literatura e uma apreciação termodinâmica das reações químicas mais relevantes em cada sistema reacional. O estudo experimental foi conduzido através da avaliação do efeito de variáveis específicas para cada sistema reacional. No caso particular de concentrados de alto teor contendo flúor, os experimentos contemplaram a presença, ou não, de água na atmosfera reacional ao passo que nos ensaios envolvendo concentrados de baixo teor de cobre foram levados a efeito variando a temperatura e a composição química da atmosfera reacional a partir da recirculação de parte dos produtos gasosos, como, por exemplo, o SO2. Os materiais envolvidos foram caracterizados por meio de microscopia eletrônica de varredura e difração de raios-x. As previsões teóricas de ambos os sistemas reacionais puderam ser confirmadas na caracterização dos produtos reacionais obtidos após o processamento químico dos concentrados sulfetados de alto e baixo teor de cobre. No que tange o primeiro destes, observou-se que o flúor tende a permanecer estável na forma de fluorita quando na ausência de umidade no sistema reacional. Por outro lado, no que diz respeito ao último destes materiais, verificou-se que o reciclo de parte dos produtos gasosos do processo é responsável por uma melhora de desempenho da reação química de ustulação visando à formação seletiva de sulfato de cobre e óxido de ferro.<br>Sulfide minerals concentrates are an important source of raw materials for non-ferrous metals extraction processes. For copper, these are usually processed through a flowchart containing the operations of roasting, matte smelting, conversion and refining. However, some concentrates characteristics may limit its acceptance in processing plants such as low copper content and the presence of deleterious elements, such as fluorine and its corrosive effects as result of its transformation into hydrofluoric acid; even if the metal content is this material is high. Within this context, this study aims to evaluate the chemical processing of sulfide concentrates with these characteristics in order to understand their roasting behavior, in order to identify conditions that minimize the fluorine harmful effects for concentrate with high copper content, and determine an operating window that allows the selective obtainment of CuSO4, for low grade concentrates. To meet these objectives, it was carried out a theoretical study including a brief review of the literature and a thermodynamics assessment of the most important chemical reactions in each reaction system. The experimental study was conducted evaluating the effect of specific variables for each reaction system. In the case of concentrates of high grade containing fluorine, the experiments contemplate the presence or absence of water in the reaction atmosphere while the tests involving the concentrate with low copper content were carried out by varying the temperature and the chemical composition of the atmosphere, recirculating part of the gaseous products, like SO2. The materials were characterized by scanning electron microscopy and x-ray diffraction. The theoretical predictions of both reaction systems could be confirmed in the characterization of the reaction products obtained after the chemical processing of sulfide concentrates of high and low copper content. In what touches the former, it was observed that fluorine tends to remain stable as fluorite in the absence of moisture within the reaction system. On the other hand, regarding the latter material, it was found that the part of recycled gaseous products of the process are responsible for a performance improvement of the roasting reaction focused on the selective formation of copper sulfate and iron oxide.
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Einar, Lidén. "Chemical Analysis of the Contents of Ancient Kohl Pots from the Nubian Kingdom." Thesis, Uppsala universitet, Institutionen för kemi - BMC, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-443282.
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Nilsson, Linnea, and Sahra Svensson. "Consumer product contents information from the 1st tier supplier : Obstacles to 1st tier supplier compliance to product contents information requirements and useful supply chain management practices to ensure supplier compliance." Thesis, Blekinge Tekniska Högskola, Institutionen för industriell ekonomi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-13040.
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Purpose: The purpose of this thesis is to identify the obstacles against supplier compliance, which focal companies encounter within the upstream supply chain when attempting to collect the requested product contents information. Based on this problem, the objective is to identify the most useful supply chain management practices to ensure supplier compliance.Method: The theoretical framework contains the Principal-Agent theory and Responsible Supply Chain Management. The empirical findings are derived through semi-structured interviews that were conducted with three Swedish corporations operating in China and one Swedish-Chinese consulting firm.Results: The two main-obstacles to supplier compliance were firstly found to consist of lacking supplier understanding of the product contents information requirements (PCIR). These obstacles prevented the supplier from understanding the risk at hand and what behaviour that triggered the risk. The second main-obstacles were found to be the prevalence of different opposing interests, which could all be traced back to the reluctance to assume an increase in costs, and could induce the supplier to pursue that interest rather than the interest to comply to the PCIR. With these obstacles in mind, the main objective of the focal company’s supply chain management practices should preferably be to create risk in relation to the PCIR, ensure supplier understanding and pay attention to the opposing interests. The most useful type of supply chain management practice for fulfilling these objectives were the use of incentives, preferably in combination with sanctions, to create risk. Training was considered most useful for ensuring supplier understanding, although a combination of training, personal communication and written documents is potentially interesting. Regarding the opposing interests, accommodating practices were found most useful rather than attempt to persuade the supplier to give up the interest.
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Fard, Ebrahim Rowghani Haghighi. "Chemical and nutritional characteristics of whole-crop barley ensiled at different dry matter contents with or without silage additives." Thesis, University of Newcastle Upon Tyne, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307930.
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Zaidi, Syed Faraz Ali, and Juthatip Sudthanom. "To Analyze The Relationship between BOD, Nitrogen And Phosphorus Contents at Constant Dissolved Oxygen Concentration In Municipal Wastewater Treatment." Thesis, Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-12524.
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In this report, the application of Principle Component Analysis (PCA) and Partial Least Square (PLS) regression analyzing methods used to understand the relationship of interdependent loads in municipal wastewater treatment plant. Two different wastewater treatment plants were chosen for analysis of the relationship between interdependent loads. Firstly, the collected data of incoming wastewater and outgoing water from both Västerås and Eskilstuna wastewater treatment plants were analyzed to find some relationship or correlation between contents and compare the data of both the plants. Secondly, the correlated contents were used to generate the regression model for predicting the value in the future, in this report we have focussed only on ammonium nitrogen value for regression model. The PCA study shows the variation between incoming and outgoing wastewater’s characteristics given by Västerås and Eskilstuna plant.<br>BOD, ammonium nitrogen, nitrogen, phosphorus
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Mahfouz, Céline. "An assessment of the chemical contamination and the diet changes of the harbou porpoise (Phocoena phocoena) stranded along the southern North Sea." Thesis, Littoral, 2014. http://www.theses.fr/2014DUNK0433/document.
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De part l'importance et la diversité des pressions anthropiques en mer du Nord, les mammifères marins en tant que prédateurs supérieurs se trouvent de plus en plus exposés à ces activités (trafic maritime, activités industrielles et portuaires, surpêche, pollution chimique, etc.). Les campagnes d'observation SCANS et SCANS II mises en place en 1994 et 2005 pour estimer l'abondance des petits cétacés, ont mis en évidence un changement majeur dans la distribution du marsouin commun (Phocoena phocoena) en mer du Nord avec un déplacement du Nord vers le Sud. Ce changement peut être lié à une migration de ses proies préférentielles en mer du Nord et/ou à une afaptation de son régime alimentaire par rapport à la disponibilité des proies. Parallèlement, à ces modifications de distribution spatiale, un nombre croissant d'échouage de marsouin commun en Manche Orientale et sur les côtes belges a été observé depuis une dizaine d'années avec une augmentation conséquente ces deux dernières années. Pour étudier les causes responsables de ces échouages, un des objectifs de cette étude a été d'évaluer l'état de la contamination chimique des animaux échoués en relation avec l'état sanitaire des individus. L'analyse de deux familles de composés chimiques (éléments traces métalliques et polluants organiques persistants) sur des animaux échoués sur la période 2006-2013 révèlent des concentrations significativement plus élevées dans les organies des animaux présentant des pathologies que celles obtenues chez les animaux sains. Cette tendance a déjà été observée en Atlantique Nord pour le marsouin. Les comparaisaons des niveaux de concentration mesurées avec ceux d'études antérieures effectuées sur des marsouins échoués dans la même zone ou dans le Golfe de Gascogne suggèrent que l'augmentation du nombre de marsouins échoués n'est pas liée à une dégradation du milieu en terme de pollution chimique. Pour déterminer le régime alimentaire du marsouin commun, trois techniques complémentaires ont été utilisées : l'analyse des contenus stomacaux, des isotopes stables (carbone et azote) et des acides gras dans différents tissus. Pour ces deux dernières méthodes, les signatures obtenues pour le marsouin ont été comparées à celles de leurs proies potentielles. Les résultats ont mis en évidence la présences des gobies, merlans, lançons, sprats, trisopterus sp., harengs et sardines comme proies potentielles. Le déplacement des marsouins du nord jusqu'au sud de la mer du Nord a été attribué à la baisse de l'abondance du lançon dans le nord, ainsi qu'à la ré-invasion du sud de la mer du Nord par la sardine, probablement suite au changement climatique. Enfin, cette étude confirme la nécessité d'utiliser une approche multi-analyses qui intègre des informations complémentaires à différentes échelles de temps pour étudier le régime alimentaire de ces prédateurs supérieurs<br>The North Sea is heavely impacted by human activities such as overfishing and pollution. Due to their position as top predators in the ocean, marine mammals are becoming increasingly affected by anthropogenic activities. The large-scale surveys SCANS in 1994 and SCANS II in 2005 that were held in the North Sea to estimate the abundance of small cetaceans highlighted a major shift in the distribution of harbour porpoises (Phocoena phocoena) from the northern parts of the North Sea to its eastern parts. Alongside, over the past few decades harbour porpoises stranding has increased in the southern North Sea particularly along the French and Belgian coastal waters. Since the contaminant exposure presents, among others, a potential threat to harbour porpoises inhabiting the North Sea, the first objective of the present study was to assess the contamination status of this species in the southern North Sea. On the other hand, the distribution and abundance of marine mammals is expected to follow the distribution of their main prey species. Hence, the second objective of this study was to investigate whether the changes in the distribution of porpoises in the southern North Sea may be a result of the changes in prey availability. Moreover, the third objective was to evaluate the interest of combining three methods to investigate the diet of harbour porpoises : stomach contents, stable isotopes (carbon and nitrogen) and fatty acids analyses. First, the contamination status was evaluated through the determination of two components of chemical contaminants (metals and persistent organic pollutants) in tissues of harbour porpoises stranded along the southern North Sea between 2006 to 2013. Several chemical contaminants presented higher concentrations in diseased animals compared to healthy animals. In addition, some metallic contaminants showed bioaccumulation with age. Comparison with previous study suggests that the population status of harbor porpoises in term of chemical concentration has been stable from 1994 to 2013. This work suggested that the increase in the number of stranded individuals is not related to the decline in the quality of the environment. Secondly, the shift in the abundance of harbour porpoises was evaluated and interpreted in the light of prey species abundance. Three techniques were used in order to determine the diet of porpoises. Results highlighted the presence of gobies, whiting, sandeel, sprat, trisopterus sp., herring and sardine as potential preys. The shift of the abundance of porpoises form the northern parts of the North Sea to its southern parts was attributed to the sandeel abundance decline in the northern parts of the North Sea along with the re-invasion of the southern North Sea by the sardine species, probably in response to climate change. Finally, the value of a multi-approach dietary analysis was evaluated. Besides overcoming the limitations of each method, combining different techniques that integrate diet over days and weeks allowed gaining more complete understanding of harbour porpoise's diet
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Wofford, Sarah Jane. "How does alteration of chemical information affect assessment in male and female crayfish, Orconectes rusticus?" Bowling Green State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu149011404454945.
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Guimaraes, Alexander Savio Ramos. "Quantitative 1H N.M.R. chemical shift imaging of neuronal content." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/28128.
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Benning, B. K. "Novel high water content hydrogels." Thesis, Aston University, 2000. http://publications.aston.ac.uk/9809/.
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The addition of N-isopropyl acrylamide to an acrylamide-based composition that had previously been designed to become a contact lens, produced materials that showed smart effects in that the water content showed dependence on the temperature of the hydrating solution. Such thermo-responsive materials have potential uses in drug delivery, ultrafiltration and cell culture surfaces. Proteoglycans in nature have an important role to play in structural support where a highly hydrophilic structure maintains lubricious surfaces. Certain functional groups that impart this hydrophilicity are present in certain sulphonate monomers, Bis(3-sulphopropyl ester) itaconate, dipotassium salt (SPI), 3-Sulphopropyl ester acrylate, potassium salt (SPA) and Sodium 2-(acrylamido)-2-methyl propane sulphonate (NaAMPS). These monomers were incorporated into a HEMA-based copolymer that had been designed initially as a contact lens and the resulting effects examined. Highly hydrophilic materials resulted that showed reduced protein deposition over the neutral core material. It is postulated that a sulphonate group would have a larger number of hydration shells around it than for example methacrylic acid, leading to more dynamic exchange and so reducing the adsorption of biological solutes. A cationic monomer was added to bring back the net anionic nature of the sulphonate hydrogels and the effects studied. Ionic interactions were found to cause a reduction in the water content of the resulting materials as the mobility of the network decreased, leading to stiffer but less extensible materials. The presence of a net dominant charge, whether negative or positive, appeared to act to reduce protein deposition, but increasing equivalence in the amount of both charges served to present a more 'neutral' surface and deposition subsequently increased. The grafting of hydrophilic hydrogel layers onto silicone elastomer was attempted and the results evaluated using dynamic contact angle measurements. Following plasma oxidation to reduce the surface energy barrier to aqueous grafting chemistry, it was found that the wettability of the modified elastomers could be significantly enhanced by such treatment. The SPA-grafted material in particular hinted at an osmotic drive for rehydration that may be exploited in biomaterials.
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劉惠君 and Huijun Liu. "Chemical modification of cereal starch mutants differing in amylose content." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B3123902X.
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Liu, Huijun. "Chemical modification of cereal starch mutants differing in amylose content /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20668144.
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Reeves, Alastair Ian. "Contaminant tracking through dendro-chemical analysis of tree-radii." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=69688.
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The research used dendro-chemical analysis of ash tree rings and current year leaf litter to track Cd, Pb, Zn, Cu, Mn, Cr, and Sn spread and cycling from a closed garbage dump-toxic waste site. This technique allowed for determination of areal extent, contaminant levels and time period of initial contaminant contact. Only Zn, Sn, and Cu were found in elevated quantities in the xylem wood and Pb in the leaf litter. Elemental concentrations of Pb, Sn and Cd in xylem wood and leaves of ash were positively correlated. Tin was the only element to demonstrate a clear initial contact period and elemental accumulation with age. Significant levels of Cu accumulated in the heartwood while Zn revealed significant but inconsistent accumulated patterns. Expected attenuation zones associated with municipal solid waste landfill leachate dispersion were not found; thus the pathway for contaminant dispersion was likely through groundwater flow.<br>An elemental index was developed to facilitate the use of dendro-chemical analysis in periods of suppressed tree growth resulting from environmental pollution.
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Zhang, Tiequan. "Chemical behavior of phosphorus over time in fertilized soils." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=34486.
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Fertilizer P accumulates in soils, with potential for movement to waterways, causing eutrophication. Fertilizer P reactions in monoculture corn (Zea mays L.) production over time will determine environmentally sound soil management practices. Soil P changes over time were determined on a Chicot sandy clay loam (Grey Brown Luvisol) and a Ste. Rosalie clay (Humic Gleysol). Fertilizer P was added at 44 and 132 kg P ha$ sp{-1}$ and to the Chicot soil only, manure containing 60 kg P for the first five years. Mehlich-3 (M3) extraction, soil P fractionation, $ sp{31}$P NMR analysis, P in leaching water, and path analysis were measured. Added P increased M3 P more when manure was also added, and in clay soils. To increase M3 P by 1 kg ha$ sp{-1}$ required from 3.6 to 8.1 kg ha$ sp{-1}$ fertilizer P, and when "net" fertilizer additions were used, fertilizer required was from 1.8 to 5.3 kg P ha$ sp{-1}.$ Moderately labile organic P (Po) decreased at 0 added P. With P at the rate of plant removal, inorganic (Pi) and Po fractions were unchanged. Excess P increased labile P and resistant P through moderately labile Pi. More P remained in labile Pi fractions when manure P was added, or in the soil with the higher clay content. Soil organic P levels increased upon fertilization only in the sandy loam soil. Labile and moderately labile Po could be estimated using monoester phosphate values determined by $ sp{31}$P NMR. Inorganic P values in gravitational water increased above 0.05 mg P L$ sp{-1}$ when soil labile Pi increased above 108 mg kg$ sp{-1}$ in the sandy loam soil and 69 mg L$ sp{-1}$ in the clay soil. Thus soil P movement was related to inorganic P additions. Increased fertilizer P did not increase organic P leaching losses. Fertilizer P in corn production may result in groundwater eutrophication.
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Quintana, Vilajuana Elisabet. "Enzymatic and chemical treatments to obtain pulps with high-cellulose content." Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/403993.
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La celulosa es el polímero más abundante en la Tierra y en los últimos años ha ganado un amplio interés como fuente de nuevos productos con requisitos de procesamiento y de calidad diferentes a los procesos convencionales de obtención de pulpa y papel. Las restricciones en el cultivo de algodón y el aumento de la producción de las llamadas pulpas para disolver (dissolving pulps) ofrecen nuevas oportunidades al polímero de celulosa. Además, en comparación con los productos químicos derivados del petróleo, la celulosa permite el desarrollo de procesos y productos sostenibles y amigables con el medio ambiente. Este es el contexto que enmarca la presente tesis doctoral. El trabajo se desarrolló siguiendo básicamente dos líneas de investigación: por un lado la conversión de pulpas al sulfito a pulpas aptas para su disolución mediante la ayuda de tratamientos enzimáticos y químicos, y por otro lado la (bio)modificación de pulpas con alto contenido en celulosa. El planteamiento de estas dos líneas de investigación justificó el uso como materia prima de dos pulpas con distintas características.
La primera parte de la tesis se centra en la aplicación de enzimas para el blanqueo de pulpa de conífera procedente de una cocción al sulfito. El objetivo era explorar el potencial de algunos compuestos naturales y sintéticos para la eliminación de lignina, así como aportar una mejora en el proceso de blanqueo. Los efluentes resultantes de cada etapa se caracterizaron con el fin de evaluar el impacto ambiental de los sistemas basados en el empleo de lacasas, un aspecto poco explorado en los estudios de bioblanqueo. A continuación, el mediador con mejor eficiencia para promover la deslignificación y potenciar el efecto de blanqueo, se utilizó para desarrollar una secuencia totalmente libre de cloro (TCF), formada por el sistema lacasa-mediador (LMS), una etapa quelante (Q) y finalmente una etapa de peróxido de hidrógeno reforzado con oxígeno presurizado (PO). La pulpa obtenida presentó una blancura ISO del 90% y un satisfactorio grado de polimerización. Con el fin de comprender los efectos de los tratamientos enzimáticos en la cristalinidad y en la superficie de la cadena de celulosa, las muestras se analizaron mediante técnicas de termogravimetría y difracción de rayos X. En la segunda parte de la tesis, se estudió la conversión de estas pulpas bioblanqueadas en pulpas aptas para disolver. La purificación y modificación se llevó a cabo con la ayuda de tratamientos químicos y enzimáticos, concretamente con extracciones alcalinas fuertes y enzimas hidrolíticas (endoglucanasas). La combinación de ambos procedimientos permitió disminuir el contenido de hemicelulosas así como aumentar la solubilidad de la celulosa, aspectos deseados para su aplicación final. También se estudió la modificación de celulosa pura (fibras comerciales para disolver) mediante sistemas enzimáticos, pero enfocando la modificación en la necesidad de conferir nuevas propiedades. En la línea de mejorar la reactividad y la accesibilidad, el estudio proporciona conocimiento para entender el papel que juegan las endoglucanasas en combinación con extracciones alcalinas fuertes en la estructura de la celulosa. Por otro lado, se evaluó el uso del sistema lacasa-TEMPO para oxidar la estructura de la celulosa y conseguir una mejora de las propiedades de resistencia mecánica. Esta modificación aportó una importante mejora de la resistencia en húmedo en la pasta tratada, atribuida a la presencia de grupos aldehídos en las cadenas celulósicas capaces de generar enlaces hemiacetales (inter-fibras) con los hidroxilos libres. El potencial del sistema lacasa-TEMPO se mejoró introduciendo una etapa de pre-refino.
La última parte del trabajo ilustra la modificación química mediante reacciones de acetilación (heterogénea o homogénea) de las pulpas para disolver obtenidas a partir de procesos enzimáticos. Los resultados se compararon con una fibra para disolver disponible comercialmente, obtenida por métodos químicos tradicionales.
Para concluir, la "bioconversión" se llevó a cabo des de las etapas iniciales del blanqueo de la pulpa procedente de una cocción al sulfito hasta la determinación de las características propias de las pulpas para disolver, consiguiendo preparar films de acetato de celulosa, como producto final.<br>Cellulose is the most abundant polymer in the Earth and recently has gained wide interest as a source for new products with distinct processing and quality requirements compared to conventional processes for obtaining pulp and paper. The restrictions on cotton cultivation and the increase of dissolving pulp manufacturing provide new opportunities to cellulose polymer. In addition, compared to petroleum based chemicals, cellulose enables sustainable approaches and environmentally friendly products. This is the context that framed the present doctoral thesis. The work focused on two different research lines, namely: conversion of sulfite pulp to dissolving-grade with the aid of enzymatic and chemical treatments, and the (bio)modification of high-cellulose content pulps. The approach of two research lines, justifies the use of two pulps with different characteristics, as a feedstock.
The first part of the thesis involved the use of enzymes to bleach softwood sulfite pulp. The aim was to explore the potential of natural and synthetic compounds for lignin removal and provide an improvement in the bleaching process. The effluents resulting from each stage in the sequence were analyzed with a view to assessing the environmental impact of the laccase treatment. Afterwards, the mediator with best efficiency to promote delignification and enhance the bleaching effect, was used to develop a totally chlorine free (TCF) sequence composed of laccase-mediator system (LMS), a chelating (Q) stage and a hydrogen peroxide stage reinforced with pressurized oxygen (PO). The resulting pulp exhibited an ISO brightness of 90% and a satisfactory degree of polymerization. In order to understand the effects of enzymatic treatments caused in crystallinity and the surface of the cellulose chain, samples were analyzed by thermogravimetry and X-ray diffraction techniques.
The second part of the thesis was based on the conversion of these biobleached sulfite pulps to dissolving-grade. Purification was carried out with the aid of chemical and enzymatic treatments, specifically employing strong alkaline extractions and hydrolytic enzymes (endoglucanases). The combination of both procedures led to reduce the amount of hemicelluloses and increase the solubility behavior of cellulose, desired aspects for its final application.
Moreover, pure cellulose modification (commercial dissolving-grade pulp) by means of enzymatic systems, but with the interest to bring and develop new properties to the final products was also studied. With the purpose of improving reactivity and accessibility, the study gains knowledge on understanding the role of endoglucanases in combination with strong alkaline extraction to cellulose structure. On the other side, laccase-TEMPO system was used to evaluate the improvement of strength properties through oxidative modification of cellulose. A significant improvement in wet strength attributed to the formation of aldehyde groups in cellulose chains that facilitated inter-fiber bonding through hemiacetal linkages was observed. The ability of laccase-TEMPO system was improved by introducing a pre-refining step.
The last part of the thesis investigates the suitability of dissolving grade-pulp obtained by chemo-enzymatic processes for heterogeneous- and homogeneous-phase acetylation reactions (chemical modification). The results were compared with those from a commercially-available dissolving fiber grade, obtained by traditional chemical methods, which was used as reference. Surface acetylated handsheets and transparent cellulose acetate films were achieved.
To conclude, "bioconversion" was explored from the initial stages, with the need to bleach pulp resulted from a sulfite cooking; to the transformation stages, where dissolving pulps characteristics were achieved; until the preparation of acetate films as a final product.
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Key, Mary Elizabeth. "Student perceptions of chemical industry : influences of course syllabi, teachers, firsthand experience." Thesis, University of York, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288066.
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Clare, Steven S., University of Western Sydney, of Science Technology and Environment College, and of Science Food and Horticulture School. "Optimising the antioxidant content of red wine." THESIS_CSTE_SFH_Clare_S.xml, 2004. http://handle.uws.edu.au:8081/1959.7/569.
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The aim of the study presented in this thesis was to assess the impact of manipulations to red winemaking unit operations on the concentration of cis- and trans-resveratrol and resveratrol glucoside isomers in the resultant wines. An existing sensitive reverse-phase high performance liquid chromatography 'RP-HPLC' method was optimised to detect these compounds in wine, which permitted excellent peak resolution. The influence of four fermentative yeast strains belonging to the Saccharomyces cerevisiae species on the content of these compounds in Vitis Vinifera L. cv. Shiraz grape musts during alcoholic fermentation was assessed.The influence of malo-lactic fermentation 'MLF' in Shiraz wine was assessed using three different commercial strains. The kinetics of extraction during extended maceration was studied over a period of 21 days.The effect of various pomace contacting maceration methods on the level of cis- and trans-resveratrol and resveratrol glucoside isomers was investigated in Vitus Vinifera L. cv. Cabernet Sauvignon grape musts during alcoholic fermentation. The fate of resveratrol and piceid isomers in fortified red wine(port) was studied during the first six months of maturation in either glass or new oak vessels. The primary wine was derived from Shiraz concentrate. The various tests are discussed in detail and results given<br>Doctor of Philosophy (PhD)
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Nair, Vipinachandran. "Reduction of phytic acid content in canola meal by solid state fermentation." Thesis, University of Ottawa (Canada), 1990. http://hdl.handle.net/10393/5919.
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Solid state fermentation of canola meal has been carried out for the reduction of its phytic acid content. Several microorganisms were surveyed for this purpose. The phytic acid content of canola meal was reduced by 26%, 60% and 66% using Saccharomyces cerevisiae, Rhizopus oligosporus NRRL 2990 and Aspergillus niger NRC 401121 respectively after 120 hours of fermentation. Aspergillus ficuum NRRL 3135 was found to be the best for the reduction of phytic acid content. For this reason, this microorganism was studied more extensively. In the study of the phytase (EC 3.1.3.8) from Aspergillus ficuum NRRL 3135, it was found that the production of the enzyme in a submerged batch process was inhibited by high concentrations of glucose. The inhibition was overcome by applying a fed batch technique in the production of the enzyme. Tests carried out at different oxygen concentrations revealed that aeration had a beneficial effect on the production of the enzyme. (Abstract shortened by UMI.)
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Matter-Walstra, Klazien. "Biological and chemical characterisation of neuroblastoma associated antigens /." [S.l.] : [s.n.], 1988. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Ahmad, Riaz. "Sorption and release of pesticides in soils : the role of chemical nature of soil organic matter /." Title page, table of contents and abstract only, 1999. http://web4.library.adelaide.edu.au/theses/09PH/09pha2853.pdf.
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SCALISE, AMELIA. "Chemical characteristics and nutritional properties of pericarps and seeds in rose hips of some Rosa species grown in Italy." Doctoral thesis, Università Politecnica delle Marche, 2021. http://hdl.handle.net/11566/289291.
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L'interesse verso i cibi funzionali è in continuo aumento per il loro uso sia come fonte di nutrienti sia come promettenti rimedi per numerose malattie. Tra i vegetali più studiati negli ultimi anni le rose hanno ricevuto molta attenzione grazie alla presenza nei loro petali e nei loro cinorrodi di un alto contenuto di composti biologici attivi.
La tesi riporta i risultati dello studio della composizione fitochimica di pericarpi e semi di cinorrodi in varie specie e/o varietà di rose prelevate in alcune regioni italiane (Emilia Romagna, Marche, Lazio) per il loro possibile uso come ingredienti nelle formulazioni di cibi funzionali e/o come alternative naturali agli antiossidanti sintetici usati nella conservazione di cibi deteriorabili. I cinorrodi di undici specie e/o cultivar di Rosa sono stati prelevati in tre zone dell’Italia centro-settentrionale: Località Maciolla (Il Giardino delle rose perdute), Urbino (PU), Marche (BS = Rosa gallica “La Belle Sultane”, BPV = Rosa gallica “bella porpora violetta”) ; Parco Regionale Naturale dei Monti Simbruini, Camerata Nuova (RM), Lazio (CCN = Rosa canina) ; Collezione rose antiche dell’Istituto Agrario Persolino, Faenza, (RA), Emilia Romagna (CF = Rosa canina, RG = Rosa gallica, RA = Rosa x alba, GC = Rosa gallica complicata, RD = Rosa x damascena, GO = Rosa gallica officinalis, GR= Rosa gallica rugosa, GV = Rosa gallica versicolor).
La ricerca ha studiato la possibilità dell’uso dell’olio dei semi di cinorrodi come possibile cibo funzionale grazie alla particolare composizione in acidi grassi ed ha valutato l’efficacia di polifenoli estratti dai pericarpi dei cinorrodi nella protezione dalla perossidazione dei lipidi di due oli di girasole (classico ed alto-oleico).
I risultati hanno mostrato un contenuto variabile del contenuto totale di polifenoli nei pericarpi e nei semi dei cinorrodi e una particolare composizione in acidi grassi dei semi nelle diverse varietà di rose, tale da renderli adatti all’uso come cibi funzionali.
Il test DPPH (di-phenyl-picryl-hidrazyl) per la valutazione dell’attività antiossidante del contenuto totale di polifenoli (TPC), misurata attraverso l’EC50 (Concentrazione efficiente per l’inibizione del 50% del DPPH), ha mostrato una notevole capacità antiossidante per tutti i campioni di rosa, con un potere maggiore per quelle a minor contenuto in TPC, indicando una differente composizione chimica della componente polifenolica con preferenza per acidi fenolici e glucosidi a maggior potere antiossidante nei campioni a minor TPC.
La protezione dei due oli di girasole dalla perossidazione lipidica mostrata dai polifienoli estratti nei vari campioni di rose, valutata attraverso la percntuale di inibizione, è risultata molto elevata per tutti gli estratti, eccetto per i tre campioni con più basso TPC nell’olio di girasole classico; comunque, la qualità del TPC in questi campioni ha denotato un elevato potere antiossidante dell’unità di TPC, suggerendo la necessità di avere la giusta combinazione tra contenuto totale e qualità dei polifenoli presenti nei pericarpi di cinorrodi per l’uso di questi estratti come antiossidanti naturali in sostituzione di quelli sintetici ancora utilizzati.
Un ulteriore scopo dei tre anni di Dottorato è stato quello di stabilire uno stretto rapporto tra il Dipartimento di Scienze Agrarie, Alimentari e Ambientali dell’Università Politecnica delle Marche di Ancona e l’Istituto Alberghiero “Einstein-Nebbia” di Loreto, dove la sottoscritta è insegnante di Scienze dell’Alimentazione, per condividere con gli insegnanti e gli studenti l’esperienza di ricerca maturata nei tre anni e per indirizzare gli studenti verso il percorso Universitario previsto nel Dipartimento.<br>There is increasing interest in the use of functional foods not only as a source of nutrients but also for their promising response to numerous diseases. Among fruit and vegetable products, roses have been the focus of considerable attention due to their high content of bioactive compounds.
This thesis is focused on the study of the phytochemical composition of rosehip pericarps and seeds in selected rose plants growing in some Regions of Italy (Marche, Lazio, and Emilia Romagna), as possible ingredients in functional food formulations and/or dietary supplements in order to replace synthetic antioxidant with natural alternatives. Rosehips from eleven Rosa species and cultivars were collected from three sites in Central Italy: Località Maciolla (Il Giardino delle rose perdute), Urbino (PU), Marche Region (BS = Rosa gallica “La Belle Sultane”, BPV = Rosa gallica “bella porpora violetta”) ; Regional Natural Park of the Monti Simbruini, Camerata Nuova (RM), Lazio Region (CCN = Rosa canina) ; Persolino High School Antique Rose Collection, Faenza, (RA), Emilia Romagna Region (CF = Rosa canina, RG = Rosa gallica, RA = Rosa x alba, GC = Rosa gallica complicata, RD = Rosa x damascena, GO = Rosa gallica officinalis, GR= Rosa gallica rugosa, GV = Rosa gallica versicolor).
The research studies the possibility to use rosehip seed oil as a functional food, due to its particular fatty acid composition and evaluates the effectiveness of polyphenols extracted from rosehip pericarps in protecting two sunflower oils (classic and high-oleic) from oxidation.Results showed a variable total polyphenolic content in pericarps and seeds and a particular composition of fatty acids in the seeds of the rose species, making them a possible functional food.The DPPH scavenging test to evaluate the antioxidant activity of Total Polyphenolic Content (TPC), measured through the EC50 (Efficient Concentration for DPPH 50% inhibition), was very good for all rose samples and showed a high scavenging power when the TPC was lower, indicating a different composition of phenolic acid and glucosides in different rose samples.
The protection of the two sunflower oils (classic and high-oleic) from lipid peroxidation provided by different rose extracts, evaluated through the % inhibition, was very high for all the rose extracts, except for the three samples with the lowest TPC in classic sunflower oil; however, the TPC composition of these samples indicated a very good antioxidant power suggesting that a correct combination of quantiy and quality is needed when rosehip extracts are used as natural antioxidants.
A further aim of the three-year pHD course was to establish relationship between the Department of Agricultural, Food and Environmental Sciences of the Università Politecnica delle Marche, Ancona, italy and the High School “Einstein-Nebbia”, Loreto, Ancona, Italy whre I’m teacher of “Nutrition Sciences”, in order to share the research experience matured in the three-year PhD, with the teachers and students of this school and to address students to this kind of University experience.
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Ebune, Anne Ebane. "Production of phytase and reduction of phytic acid content in canola meal by solid state fermentation." Thesis, University of Ottawa (Canada), 1992. http://hdl.handle.net/10393/10855.
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A static state technique for fermentation was applied using Aspergillus ficuum NRRL 3135 on canola meal for the production of phytase and for the reduction of the phytic acid content in the meal. Aspergillus ficuum was chosen as a result of its high phytase producing capacity. In the study of the effects of physical and nutritional factors on the enzyme production and the phytic acid content reduction, it was found that moisture content was a critical factor and 64% water in the medium was found to be the optimum moisture content for both enzyme production and phytic acid content reduction. Increasing time of homogenization of inoculum up to 240 seconds improved enzyme production and phytic acid reduction. Increase in both inoculum concentration (biomass) and inoculum age up to 7-days old increased enzyme production and rate of phytic acid content reduction. With increase in initial pH of medium of up to 5.7, increased enzyme production and rate of phytic acid reduction were achieved. In the addition of surfactants to medium, sodium oleate was found to significantly increase enzyme production and the rate of phytic acid content reduction while Triton X-100 gave a negative effect. The addition of 1 mg phosphate remarkably increased the enzyme production and phytic acid content reduction; though a negative effect was obtained for systems containing combined portions of oleate and phosphate. Biomass in the solid culture was found to increase during fermentation up to 144 h of incubation and the protein content of culture also increased to about 18% after 96 h of incubation; hence this method of fermentation could be used to improve the nutritional quality of the meal for animal feed.
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Wildenhain, Jan. "Application of multivariate statistics and machine learning to phenotypic imaging and chemical high-content data." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/25665.
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Image-based high-content screens (HCS) hold tremendous promise for cell-based phenotypic screens. Challenges related to HCS include not only storage and management of data, but critical analysis of the complex image-based data. I implemented a data storage and screen management framework and developed approaches for data analysis of a number high-content microscopy screen formats. I visualized and analysed pilot screens to develop a robust multi-parametric assay for the identification of genes involved in DNA damage repair in HeLa cells. Further, I developed and implemented new approaches for image processing and screen data normalization. My analyses revealed that the ubiquitin ligase RNF8 plays a central role in DNA-damage response and that a related ubiquitin ligase RNF168 causes the cellular and developmental phenotypes characteristic for the RIDDLE syndrome. My approaches also uncovered a role for the MMS22LTONSL complex in DSB repair and its role in the recombination-dependent repair of stalled or collapsed replication forks. The discovery of novel bioactive molecules is a challenge because the fraction of active candidate molecules is usually small and confounded by noise in experimental readouts. Cheminformatics can improve robustness of chemical high-throughput screens and functional genomics data sets by taking structure-activity relationships into account. I applied statistics, machine learning and cheminformatics to different data sets to discern novel bioactive compounds. I showed that phenothiazines and apomorphines are regulators for cell differentiation in murine embryonic stem cells. Further, I pioneered computational methods for the identification of structural features that influence the degradation and retention of compounds in the nematode C. elegans. I used chemoinformatics to assemble a comprehensive screening library of previously approved drugs for redeployment in new bioassays. A combination of chemical genetic interactions, cheminformatics and machine learning allowed me to predict novel synergistic antifungal small molecule combinations from sensitized screens with the drug library. In another study on the biological effects of commonly prescribed psychoactive compounds, I discovered a strong link between lipophilicity and bioactivity of compounds in yeast and unexpected off-target effects that could account for unwanted side effects in humans. I also investigated structure-activity relationships and assessed the chemical diversity of a compound collection that was used to probe chemical-genetic interactions in yeast. Finally, I have made these methods and tools available to the scientific community, including an open source software package called MolClass that allows researchers to make predictions about bioactivity of small molecules based on their chemical structure.
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Svensson, Sara. "Minimizing the sulphur content in Kraft lignin." Thesis, Mälardalen University, School of Sustainable Development of Society and Technology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-998.
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<p>The aim of this project is to investigate the possibilities of minimizing the sulphur content in Kraft lignin. Kraft lignin contains about 1.5 to 3% sulphur. The sulphur is believed to be present in lignin as inorganic sulphur, as elemental sulphur, as adsorbed polysulphide and/or as organically bound sulphur. For the determination of these different types of sulphur components, different approaches and methods were used. For the determination of inorganic sulphur, lignin was washed with water at pH 6 and pH 2 and the wash waters were analysed with ion chromatography (IC). For the determination of total sulphur content in the lignin, two methods were used; Schöniger combustion followed by ion chromatography (IC) and wet digestion followed by inductively coupled plasma (ICP). The elemental sulphur content in water-extracted lignin was determined after n-pentane extraction. ICP analysis was performed on the washed lignin.</p><p>Calcium present in the lignin may bind polysulphides and thus be a source of the observed sulphur. The lignin was thus ion-exchanged to remove any calcium. To further investigate how the sulphur content in lignin can be decreased, two different types of reactions were performed on lignin; oxidation and reduction. The oxidation reactions were made in sodium hydroxide with oxygen at different temperatures and time on both original and water-extracted lignin. The reduction reactions were made on water-extracted lignin with Raney nickel in three different solvent systems: methanol: water, acetone: water and sodium hydroxide.</p><p> </p><p>The original lignin contained 2.6% sulphur as determined by ICP. Washing lowered the content to 1.85% sulphur. By n-pentane extraction the elemental sulphur was lowered to a level of 1.82% sulphur, which was considered to be organically bound sulphur. Neither the ion exchange nor the oxidation lowered the sulphur content significantly.</p><p> </p><p>The reduction reactions successfully the organically bound sulphur from 1.82% to a level of 0.54%.</p><p> </p><p>The relative distribution of the sulphur content in the studied softwood lignin was as follows: about 29% as inorganic sulphur, about 1% as elemental sulphur and approximately 70% as organically bound sulphur, of which 49% could be removed by Raney nickel.</p>
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Sivaraman, Anand 1977. "A microfabricated 3D tissue engineered "Liver on a Chip" : information content assays for in vitro drug metabolism studies." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/28661.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2004.<br>Includes bibliographical references (p. 180-195).<br>(cont.) approaches to improving hepatocyte function in culture have been described, not all of the important functions--specifically the biotransformation functions of the liver--can as yet be replicated at desired in ivo levels, especially in culture formats amenable to routine use in drug development. The in vivo microenvironment of hepatocytes in the liver capillary bed includes signaling mechanisms mediated by cell-cell and cell-matrix interactions, soluble factors, and mechanical forces. This thesis focuses on the design, fabrication, modeling and characterization of a microfabricated bioreactor system that attempts to mimic the in vivo microenvironment by allowing for the three dimensional morphogenesis of liver tissue under continuous perfusion conditions. A key feature of the bioreactor that was designed is the distribution of cells into many tiny ([approximately]0.001 cm³) tissue units that are uniformly perfused with culture medium. The total mass of tissue in the system is readily adjusted for applications requiring only a few thousand cells to those requiring over a million cells by keeping the microenvironment the same and scaling the total number of tissue units in the reactor. Using a computational fluid dynamic model in ADINA® and a species conservation mass transfer model in FEMLAB®, the design of the bioreactor and the fluidic circuit was optimized to mimic physiological shear stress rates ...<br>Recent reports indicate that it takes nearly $800 million dollars and 10-15 years of development time to bring a drug to market. The pre-clinical stage of the drug development process includes a panel of screens with in vitro models followed by comprehensive studies in animals to make quantitative and qualitative predictions of the main pharmacodynamic, pharmacokinetic, and toxicological properties of the candidate drug. Nearly 90% of the lead candidates identified by current in vitro screens fail to become drugs. Among lead compounds that progress to Phase I clinical trials, more than 50% fail due to unforeseen human liver toxicity and bioavailability issues. Clearly, better methods are needed to predict human responses to drugs. The liver is the most important site of drug metabolism and a variety of ex vivo and in vitro model systems have therefore been developed to mimic key aspects of the in vivo biotransformation pathways of human liver-- a pre-requisite for a good, predictive pharmacologically relevant screen. Drug metabolism or biotransformation in the liver involves a set of Phase I (or p450 mediated) and Phase II enzyme reactions that affect the overall therapeutic and toxic profile of a drug. The liver is also a key site of drug toxicity following biotransformation, a response that is desirable but difficult to mimic in vitro. A major barrier to predictive liver metabolism and toxicology is the rapid (hours) loss of liver-specific functions in isolated hepatocytes when maintained under standard in itrom cell culture condition. This loss of function may be especially important in predicting toxicology, where the time scale for toxic response may greatly exceed the time scale for loss of hepatocyte function in culture. Although a wide variety of<br>by Anand Sivaraman.<br>Ph.D.
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Kerbrat, Michael. "Physico-chemical interactions of acidic trace gases with ice in snow /." [S.l.] : [s.n.], 2009. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Al-Asheh, Sameer. "Production of phytase and reduction of phytic acid content in canola meal by solid state fermentation using Aspergillus carbonarius." Thesis, University of Ottawa (Canada), 1993. http://hdl.handle.net/10393/7578.
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Solid state fermentation (SSF) with canola meal as substrate was carried out to study the production of phytase and the reduction of the phytic acid content in the meal using Aspergillus carbonarius NRC 401124. Some characteristics of the phytase were studied. $K\sb{\rm m}$ and $\nu\sb{max}$ values of 0.345 mM and 0.8071 units were determined when sodium phytate was used as the substrate for this enzyme. The enzyme showed an optimum pH and temperature of 4.7 and 53$\sp\circ$C respectively. It was found that the production of phytase was growth associated and that the maximum activity was attained after 72 h of incubation during SSF process. Apparent increases of about 25% and 10% of protein content of canola meal were noticed after 48 h and 72 h of the process respectively. A 25% reduction in the total carbohydrate concentration was reached at the end of fermentation. The rate of the reduction of phytic acid content of the meal depended on the physical parameters of the SSF. The optimum particle size of the meal for this process was found to be 1.4 mm, and negative results are noticed with particle sizes higher than 1.4 mm. It was found that the increase in glucose amount up to and including 6 g per system in the initial medium resulted in an increase in the rate of the biomass growth, enzyme concentration and the rate of phytic acid content reduction in canola meal. The addition of 1 mg of phosphate per system remarkably increased the biomass and enzyme productions and phytic acid content reduction. Sodium oleate increased the biomass and enzyme productions and the rate of phytic acid content reduction, while Triton X-100 gave a negative effect. (Abstract shortened by UMI.)
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Martinez, Beltran Emerson R. "Decrease of HT chlorogenic acid content in sunflower meal using an enzyme preparation secreted by the white-rot fungus Trametes versicolor." Thesis, University of Ottawa (Canada), 2003. http://hdl.handle.net/10393/26830.
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This project describes the enzymatic degradation of chlorogenic acid (CGA) in a model system with pure CGA and in a sunflower meal (SFM) system. The effects of several parameters, such as pH, temperature, and substrate, enzyme and sunflower meal concentrations, on the decrease of the CGA concentration were studied. The optimum pH was found to be 4.3 for the model system and 3.4 for the SFM system; the difference in pH was due to the buffering capacity of the meal in the SFM system. The optimum temperature was 45°C for both systems. There is a linear relationship between the enzyme concentration and the initial reaction rate for low enzyme concentrations. That linearity disappears when the enzyme concentration was higher than 1 nkat/mL and 2.2 nkat/mL for the model and SFM systems, respectively. Regarding the effect of the substrate concentration, a saturation with substrate was noticed when its concentration was 0.13 mM. (Abstract shortened by UMI.)
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Andersson, Hanna. "Vattenhaltmätning i konfektyr och sylt med Karl Fishermetoden." Thesis, Växjö University, School of Technology and Design, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-1023.
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<p>Abstract (in English)</p><p>The task for the diploma work was to develop methods for measuring of moisture content by the Karl Fischer method, in jam, jelly sweets, and fudge.</p><p>The start premises was a for the company whole new equipment, which should be started up. Then programs should be developed for different kind of samples.</p><p>In the task it was as well included to develop methods for dissolving the different kind of samples, since the Karl Fischer method demands completely dissolved sample material.</p>
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Armstrong, Brian. "The study of pharmaceutical powder mixing through improved flow property characterisation and tomographic imaging of blend content uniformity." Thesis, University of Birmingham, 2011. http://etheses.bham.ac.uk//id/eprint/1681/.
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The regulatory framework in which pharmaceutical companies have to work has changed significantly since the late 1990’s. The development and implementation of risk based approaches to processing pharmaceutical powders allows the pharmaceutical manufacturers the freedom to adopt real-time release for their products whist reducing the regulatory burden for both the statutory bodies and the manufacturers. This thesis has been a collaboration between Buck Systems and the University of Birmingham School of Chemical Engineering to evaluate and develop methods which would enhance the way in which Buck Systems can, in co-operation with their clients, enhance their understanding of how powder properties affect their products that are used in pharmaceutical manufacturing to better comply with the changes in the regulatory environment. To this end simple and quick screening methods for characterisation of customers’ powders with a view to identifying potential problems prior to blending tests have been developed to replace the current ad hoc approach. These include the use of tests that have been relied on historically as well as newer, more universal and robust techniques such as automated shear cells and powder rheometers. Detailed characterisation trials have shown where these techniques can be successfully applied and where their limitations lie. Further work has shown how powder systems can be better evaluated within the existing HAZOP framework. Specific evaluation of the hopper design methodology has resulted in the development of an expert system to enable the rapid sensitivity analysis of design options. In addition the limits of the hopper design method have been explored and some limitations identified where significant overdesign may occur. The evaluation of content uniformity in a laboratory scale blender using specialist Positron Imaging equipment available at the University of Birmingham has also been undertaken. The unique study of the blender contents using Positron Emission Tomography has provided a range of insights into the way binary and ternary powder systems interdisperse.
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Walkowiak, Wiesław. "Investigation of influence of the chemical composition and structure of selected hard coatings, deposited of PVD methods, on their mechanical properties : doctoral dissertation." Rozprawa doktorska, [s.n.], 2001. http://dlibra.tu.koszalin.pl/Content/1224.
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Hübner, Reinhard. "Strategic supply chain management in process industries an application to specialty chemicals production network design ; with 22 tables." Berlin Heidelberg Springer, 2006. http://www.springerlink.com/content/q76822.
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Buchanan, Susan. "Effect Of Chemical Agents On Acid Production In, And The Microbial Content Of, Pits And Fissures." Thesis, The University of Sydney, 1988. http://hdl.handle.net/2123/4967.
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Master of Dental Surgery<br>This work was digitised and made available on open access by the University of Sydney, Faculty of Dentistry and Sydney eScholarship . It may only be used for the purposes of research and study. Where possible, the Faculty will try to notify the author of this work. If you have any inquiries or issues regarding this work being made available please contact the Sydney eScholarship Repository Coordinator - ses@library.usyd.edu.au
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Buchanan, Susan. "Effect Of Chemical Agents On Acid Production In, And The Microbial Content Of, Pits And Fissures." University of Sydney, 1988. http://hdl.handle.net/2123/4967.
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Master of Dental Surgery<br>This work was digitised and made available on open access by the University of Sydney, Faculty of Dentistry and Sydney eScholarship . It may only be used for the purposes of research and study. Where possible, the Faculty will try to notify the author of this work. If you have any inquiries or issues regarding this work being made available please contact the Sydney eScholarship Repository Coordinator - ses@library.usyd.edu.au
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Müller, Nils. "Characterization of dangerous pollutants in bio and waste ashes : Analysing content and leaching behaviour of several ashes for persistent organic pollutants and toxic heavy metals." Thesis, Umeå universitet, Kemiska institutionen, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-138124.
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Schultze, Felix. "Coteaching chemical bonding with Upper secondary senior students : A way to refine teachers PCK." Licentiate thesis, Linköpings universitet, Lärande, Estetik, Naturvetenskap (LEN), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-152778.
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The aim of this study was to investigate how an experienced chemistry teacher gains and refines her pedagogical content knowledge (PCK) by cooperating with two grade 12 students (age 18) as coteachers while teaching chemical bonding in a grade 10 Upper secondary class. The study has been conducted from a sociocultural perspective, especially Vygotsky’s zone of proximal development (ZPD) (Vygotsky, 1978). Other theoretical concepts and models that has framed this study are Shulman´s Pedagogical content knowledge (PCK) and Pedagogical reasoning and action model (Shulman, 1986, 1987). When analysing the data, Magnusson, Krajcik, and Borko´s (1999) model of PCK and the 2017 Refined consensus model of PCK (Carlson, Daehler, et al., in press) was used. Empirical data was collected by video- and audio recorded lessons, coreflection sessions, coplanning sessions and interviews. During 10 weeks, about 28 hours of video and audio recordings was collected. Selected parts of the material were transcribed and analysed in order to answer two questions: (1) How can chemistry teachers refine their PCK when coteaching together with senior students in an Upper secondary science class? (2) How do Upper secondary senior student coteachers´ conceptual knowledge of representations and chemical bonding shape a teacher’s foundation of personal PCK (pPCK) when teaching chemical bonding in an Upper secondary science class? The results relating to research question one indicates that the coteachers contributed with their own learning experiences to help the teacher understand how students perceive difficult concepts. The coteachers were mediating between the teacher and the students, thus bridging the gap between the teacher and the students’ frames of references. The experienced chemistry teacher improved her understanding of students´ thinking about themselves as learners of chemical bonding. Regarding the second research question, the findings showed that the creative process of reconstructing concepts of chemical bonding in the coplanning sessions meant that these were a useful tool for developing new teaching strategies and to further develop representations such as drama to illustrate chemical bonding. Together, the teacher and student coteachers, constructed a new representation that better illustrated polar covalent bonding. Taken together, these results provide important insights into how the chemistry teacher´s pPCK was refined and how the coteachers contributed to improve instructional strategies.
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Alaswad, Alaa A. "DEVELOPMENT OF CHEMICALLY MUTAGENIZED SOYBEAN POPULATIONS FOR IMPROVING SOYBEAN SEED OIL CONTENT AND FORWARD AND REVERSE GENETICS SCREENING." OpenSIUC, 2014. https://opensiuc.lib.siu.edu/theses/1421.
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Soybeans are among seeds the common plant foods that contains high protein contents and high oil. The protein provides about 35 to 38 percent of the seeds calories compared to around 20 to 30 percent in other legumes and many animal products. The quality of soy protein is notable and approaches the quality of meat and milk. Unlike many other good sources of protein, soybeans are low in saturated fat and are cholesterol-free. Its proteins provide all the important amino acids, most the amounts needed by humans (NSRL, 2010). As the most consumed vegetable oil in the world, soybean oil has been used substantially in the food industry (Soystats, 2010). Its utilization is determined by its fatty acid composition, with commodity soybean oil typically 13% palmatic acid (16:0), 4% stearic acid (18:0), 20% oleic acid (18:1), 55% linoleic acid (18:2), and 8% linolenic acid (18:3). The change of fatty acid profiles to improve soybean oil quality has been a long time goal of many researchers throughout the world. Biodiesel is an up and coming trend in energy production. Breeding effort can be undertaken in order to produce a higher energy profile soybean oil. Using ethyl-methanesulfonate (EMS) mutagenesis effects on DNA, significant changes to the genes and gene network underlying the protein and oil profile can be achieved. These changes are hard to accomplish using standard breeding techniques. In addition, high amount of linolenic and stearic acid are very important for fuel and biodiesel production, but are not good for food production due to the fact that such oil is oxidized easily and the food goes rancid quickly. However, soybean oil with elevated amount of oleic acid is desirable for food, because this monounsaturated fatty acid improves the nutrition and oxidative stability of soybean oil compared to other oils. In order to improve the quality of soybean oil and processed foods, chemically mutagenized soybeans have been developed in this project. Seeds harvested from individual M3 and M4 plants (from 2 successive years 2012 and 2013) were analyzed for protein content, oil composition, and content. Moreover, seven phenotypic traits including oil analysis (stearic, palmitic, oleic, linolenic and linoleic), seed protein content, weight of the seeds (High yield), seeds color, stem length, germination rates, and branch architecture were collected and analyzed in this project of soybean `Forrest' mutagenized population. The result of this research showed that there were 25 significantly different lines (p< 0.05) compare to the wild type, which is useful for developing mutants with altered oil and fatty acid compositions in soybean.
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Rahman, Md Mostafizur. "Influences of biodiesel chemical compositions and physical properties on engine exhaust particle emissions." Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/82754/8/Md_Rahman_Thesis.pdf.
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This thesis presents a comprehensive study on the influences of biodiesel chemical composition and physical properties on diesel engine exhaust particle emissions. It examines biodiesels from several feedstocks having wide variations in their chemical composition (carbon chain length, unsaturation and oxygen content) and physical properties (density, viscosity, surface tension, boiling point etc.), and evaluates their influence on exhaust particle emissions. The outcome of this thesis is significant since it reveals the importance of regulating biodiesels chemical composition in order to ensure lowest possible emissions with better overall performance.
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Bunn, Robert Michael. "The application of statistical methods to the determination of slight differences in the chemical content of biological matrices." Thesis, University of Reading, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.408211.
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Collioud, André. "Photoinduced oriented immobilization of biomolecules on chemically inert supports /." [S.l.] : [s.n.], 1993. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Thyrén, Linnea. "Plant-based meat substitutes and their nutritional composition : A study on iron content, zinc content, calcium content and protein quality in meatballs and plant-based substitutes and how they contribute to the goal of reaching recommended daily intakes." Thesis, Linnéuniversitetet, Institutionen för kemi och biomedicin (KOB), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-96761.
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The purpose of this thesis was to study similarities and differences between a meat product and its plant-based substitutes in terms of how they enable people to reach the recommended daily intakes (RDI). The meat product included in the study were meatballs and its substitutes were three different plant-based alternatives. One was mainly based on soy, one on pea protein and one consisted of several different vegetables. The parameters studied were iron, zinc and calcium content as well as protein quality. By analyzing the four different products with flame atomic absorption spectroscopy (FAAS), the mineral content was calculated and protein quality was determined using amino acid analyzis carried out by the laboratory analysis company ALS. The method used to determine protein quality was DIAAS (Digestible Indispensable Amino Acid Score). Example meals and example days were created to visualize any differences and similarities when the products were put in a wider perspective. The results showed that there were differences between the products when they were compared individually, but that the differences were negligible when the products were included in an example meal or example day. This indicates that the products fulfill comparable dietary requirements and that the plant-based products were good substitutes for the meat product. The soy-based product was the best plant-based alternative when it comes to iron content, calcium content and protein quality. However, the soy product and the remaining substitutes reached recommended intakes for the same parameters when included in example days, which shows that the differences between the products are only present when analyzed individually.
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Calmeyn, Timothy J. "Optimization of the melt-phase polyethylene terephthalate manufacturing process." Ohio : Ohio University, 1995. http://www.ohiolink.edu/etd/view.cgi?ohiou1179336415.
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Johnson, William J. "The Effect of Chemical Composition of Blast-Furnace Slag on Compressive Strength and Durability Properties of Mortar Specimens." Scholar Commons, 2017. https://scholarcommons.usf.edu/etd/7410.
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In an effort to make structures more sustainable and durable, supplementary cementitious materials are often used to replace cement. Ground granulated blast furnace slag, for instance, is an industrial by-product of iron refinement and is frequently used in concrete mixture design to not only reduce cost, but also increase later-age strength as well as durability. However, published literature indicates that slags with a high alumina content may have a detrimental effect when concrete is exposed to a sulfate environment. ASTM standard C989 does not suggest any information or guidelines regarding using slags with an alumina content between 11-18%. Therefore, the objective of this study was to fill in the gap of this standard by studying slags of variable alumina content as high as 16 percent.
This study presents data collected for compressive strengths of mortar cubes exposed to lime and 5 percent sodium sulfate solution at ages of 7, 28, 91, and 182 days from the date of mixing as well as expansion data for mortar bar specimens exposed to 5 percent sodium sulfate solution up to 120 days. Slag replacement levels used here were 0, 30, 50, and 70%. Mortar bar specimens showing deterioration were analyzed using x-ray diffraction coupled with Rietveld refinement to assess the mechanism of deterioration. Cubes were stored in lime and sulfate solutions abiding by ASTM C1012 in order to analyze the resistance to sulfate attack. Sulfate resistance was measured in terms of decalcification of the CSH gel as well as expansion.
The results suggest using high alumina slags at a low percentage adversely affects sulfate resistance since the acquired strength at 182 days fell below that of 28 day strength, which is often used in the industry as the parameter which constitutes whether a mixture is adequate. It was also seen that increasing alumina content of the slag resulted in increased expansion. X-ray diffraction analysis indicates that the mechanism of deterioration, of the control as well as the blended mortar, is due to secondary gypsum and secondary ettringite formation. Therefore, it is recommended that slags having a high alumina content should be further analyzed in laboratory tests to examine their performance especially if concrete will be subjected to a sulfate environment during its service life.
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Bergqvist, Anna. "Teaching and learning of chemical bonding models : Aspects of textbooks, students’ understanding and teachers’ professional knowledge." Doctoral thesis, Karlstads universitet, Institutionen för ingenjörs- och kemivetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-48502.
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Despite the growing importance of science and technology in society, school students consider these subjects irrelevant and hard to learn. Teachers must therefore know how to teach science in ways that enhance students’ understanding and interest. This thesis explores various aspects of the teaching and learning of chemical bonding, an important topic in school chemistry that is primarily taught using models. Research has shown that students find chemical bonding difficult to understand, and that the use of models in science education contributes to this difficulty. I therefore investigated teachers’ knowledge of how to teach chemical bonding and ways of developing it to improve students’ understanding. To this end, I analysed chemistry textbooks and teachers’ lesson plans, and conducted semi-structured interviews with teachers about their teaching of chemical bonding. This revealed that the representations of chemical bonding used in textbooks and by teachers can cause students difficulties. The teachers were generally unaware of how these representations might affect students’ understanding, implying that their pedagogical content knowledge (PCK) could be improved. To explore ways of incorporating research findings into teaching practice and developing teachers’ PCK, I conducted a learning study in which three secondary science teachers together explored and reflected on their own teaching practice. CoRe, a method for creating detailed descriptions of what, how, and why specific content is taught, was used to enhance the reflections and make the teachers’ PCK explicit. As a result, the teachers developed their representations of chemical bonding, became more aware of students’ understanding, and were better able to motivate their actions and choices of content and strategies. This thesis shows how professional development can bridge the gap between research and teaching practice, and how teachers’ PCK can be developed to improve students’ understanding.<br>Many complex real-world phenomena can only be understood using models that make the abstract visible and provide explanations, predictions, descriptions, or simplifications. However, research has shown that students have difficulties understanding models used in science education in general, and particularly chemical bonding models. This thesis examines various aspects of the teaching and learning of chemical bonding, and its presentation in textbooks and by teachers. It is shown that the representations used by teachers and in textbooks can cause students to have difficulties in understanding, which teachers were generally unaware of. Teachers rarely justify their choices specifically to overcome students’ difficulties, suggesting that their knowledge of how to teach chemical bonding could be improved. A learning study in which teachers collaboratively explored and reflected on their own teaching practice significantly improved their presentation of chemical bonding, their awareness of students’ understanding, and their ability to justify their choices. Overall, this work shows that there is a gap between research and teaching practice, and that effective ways of incorporating research results into teaching practice are needed to improve teaching and learning in chemistry.
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Csavina, Janae L. "The Optimization of Growth Rate and Lipid Content from Select Algae Strains." Ohio University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1215529734.
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Rizza, Giorgio. "Citrus Limonoids: Functional Chemicals in Agriculture and Foods." Doctoral thesis, Università di Catania, 2016. http://hdl.handle.net/10761/4026.
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The search for limonoids started long back when scientists started looking for the factor responsible for bitterness in citrus. Studies showed that limonoids are highly oxygenated, modified terpenoids and have recently attracted attention because compounds belonging to this group have exhibited a range of biological activities like insecticidal, insect antifeedant and growth regulating activity on insects as well as antibacterial, antifungal, antimalarial, anticancer, antiviral and a number of other pharmacological activities on humans.
Based on this premise this paper has focused on technological, healthful and chemical aspects of the limonoids.
-TECHNOLOGICAL APPROACH:
Based on a project titled Enhancement of bioactive compounds isolated from agro-industrial wastes financially supported by the Italian Ministry of Education, a Sicilian juice company wanted to assess the possibility of transforming the waste by-product of citrus processing (pastazzo) in a resource trying to turn it into dietary fiber. To do that, the company has inserted a debittering line to the plant using an alkaline aqueous solution in order to extract flavanones and limonoids.
In the present paper the operational conditions of debittering were evaluated and optimized by determining the limonin content of samples from various stages of fiber production; It was also verified if the recovery of limonin extracted was economically viable.
-HEALTHFUL AND ORGANOLEPTIC CHARACTERISTICS:
It has been established that U.S. producers are turning to organic farming system as a potential way to lower input costs, decrease reliance on nonrenewable resources, capture high-value markets at premium price, and boost-farm income. Organic production agriculture is characterized by inputs of biologically (non-synthetic) based fertilizers and pest management practices that are sustainable.
In order to understand if the market source contributes to differences in bioactives content, the bio-actives content of fruits obtained from farmers' markets was compared to the content found in fruit purchased from retail grocery stores. Organoleptic properties, including Brix, TTA, color and pH were measured. Limonin, ascorbic acid and flavanoid contents were also determined.
-SYNTHESIS AND CHARACTERIZATION OF FUNCTIONAL COMPOUNDS:
Ehrlich s reagent, p-dimethylaminobenzaldehyde (DMBA) in hydrochloric acid, has a long history and is known as the coloring reagent of pyrrole. 2,3.
When a solution of limonoids is treated with p-dimethylaminobenzaldehyde in acid environment the solution immediately change to red-purple until dark blue. This reaction has named Ehrlich s reaction and the purple coloring is probably due to the presence of an adduct compound with an electron-rich trisubstituted furan ring.
In order to determine the structure of the limonin-DMBA and limonin glucoside-DMBA adducts, both compounds have been synthesized, purified and characterized. This project involves synthesis of the target compounds. MS analysis were conducted for the characterization of the isolated products.
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Shapero-Holder, Barbara C. "Contributory role status and the development and treatment of chemical dependence a contextual enhancement of current recovery models /." View full text, 2003.
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Chiao, Pi-Ying, and 焦碧瑩. "Studies on chemical composition and heavy metal contents in commercial edible seaweeds." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/55jh3p.
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碩士<br>國立臺灣海洋大學<br>食品科學系<br>106<br>The purpose of this study is to analyze proximate compositions, free amino acids (FAA), minerals, trace elements and heavy metals in edible seaweed samples. They were 6 kinds of red seaweed and brown seaweed, and 2 kinds of green seaweed samples which were collected from the market. There are significant differences in proximate composition among seaweeds. The moisture in 14 kinds of seaweed ranged from 7 to 44%¸ ash 2 to 28%, and crude protein 2 to 28%. Trace amounts of crude lipid were found in all samples. The pH value in the seaweed products was between 5.78-10.21. Red seaweed was in a weakly alkaline ranged from 6.67 to 10.21, and brown and green seaweed were in a weakly acidity from 5.78 to 7.00. Some seaweeds had much higher pH value. It might due to wash and clean seaweeds with alkaline solvent during processing. There is remarkable difference in the content of free amino acid (FAA) among species. Saccharina japonica and Durvillaea antarctica had high levels of FAA with 1716-2671 mg/100g, but those of Eucheuma denticulatum, Eucheuma serra and Undaria pinnatifida were lower than 100 mg/100 g. Porphyra dentata had more kinds of FAA among samples. Brown seaweeds possessed higher amounts of aspartic acid, glutamic acid and alanine. For Ulva lactuca, it had much more taurine than any other seaweeds. There is remarkable difference in the contents of minerals in seaweeds. The amount of sodium ranged 706-91975 ppm, potassium 991-88191 ppm, calcium 1847-29453 ppm, and magnesium 1170-37915 ppm were found in seaweeds. For the trace elements in the seaweed products, the amount of iron was 36-927 ppm, manganese 0-5.76 ppm, chromium 0-0.04 ppm, copper 0.8-21.4 ppm, and zinc 1.28-23.13 ppm. The amounts of trace elements showed significant difference in different species of seaweeds expect for chromium. Even the same species of Ulva lactuca, the contents of iron and manganese in different samples also showed remarkable difference. There was 3.46 ppm of lead in Gelidium amansii, but other seaweeds has less. The average amount of lead in red seaweed was higher than those of brown and green seaweed. According to food sanitary standards, all samples meet the regulation limit as calculated the moisture of seaweed with 85% of moisture such as fresh one. Cadmium was found in samples, but all are under the limit. The contents of mercury ranged from 0.02-0.04 ppm which was in compliance with the limit. The high levels of aluminum were found in Gelidium amansii (809 ppm), KappapHycus alvarezii (461 ppm) and PorpHyra dentate (357 ppm). The use of aluminum as leaveners in those seaweeds may result in high levels of aluminum in the products. The amount of arsenic in the seaweed products was between 0.84-46.36 ppm. Inorganic arsenic As2O3 and NaAsO3 of the samples do not exceed the regulation limit 1 ppm after converting the moisture of seaweed to 85%. The results could provide the information regarding basic nutrient substances, flavor compounds, trace elements, minerals and heavy metals in seaweeds. It also could be a reference for consumers to purchase edible seaweed and for government agency to set the limit standard of seaweed.
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Sylvander, Brendan A. "The Southeast Indian Ridge water contents of MORB glasses and chemical effects of propagating rifts." Thesis, 1998. http://hdl.handle.net/1957/27787.
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Lee, Ying-Chieh, and 李盈潔. "Study on the Relationships between the Characters of LaboratoryWastewater and the Contents of Chemical- Experimental Courses in Two Technical Schools." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/76308799676792135631.
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碩士<br>國立屏東科技大學<br>環境工程與科學系所<br>97<br>According to the Waste Treatment Act, which was amended and announced by the Environmental Protection Administration on May 30, 1996, is indicated that because a laboratory in a school is considered a business unit, the waste produced by school laboratory should be treated as one of Industrial Wastes. Besides, the waste in schools should be categorized as: (1) Campus wastes, including waste in classrooms, waste in dormitories, environment-cleaning waste, waste in public areas, and waste in offices; (2) Laboratory Waste; (3) Other Wastes, including waste equipments, construction waste, domestic waste water, and normal sludge. This thesis is mainly focused on the relationship between the production quantity of laboratory waste and the content of chemicals experiment classes in chemistry laboratory class at a chosen National Pingtung University of Science and Technology and a National Pingtung Senior Industrial Vocational School. The results indicated that the major amount of wastewater source in laboratories at National Pingtung University of Science and Technology came from: space (1) General chemistry experiment course, space especially from the terms of solution preparation, heat of reaction determination, and law of definite proportions;(2) Organic chemistry experiment course, in terms of the extraction of benzene and alcohol;(3) Analytic experiment course, such as redox- 0.1N KMnO4 preparation and calibration, precipitation titration of iodine- analysis of residual chlorine in water (Mohr’s Law), titration of iodine- 0.1M Na2S2O3 preparation and calibration. On the other hand, the result also indicated that the major sources of wastewater amount in laboratories at National Pingtung Senior Industrial Vocational School came from:(1) General chemistry experiment course, especially for the terms of the property and condensation of colloidal solution, the preparation and property of oxygen and carbon dioxide (CO2), and reaction rate determination;(2) Organic chemistry experiment course, space in terms of extraction, preparation and reaction of n-type halogen, and preparation and reaction of acetylene-type;(3) Analytic experiment, including content determination of chlorine in soluble chloride, content determination of aluminum in potassium alum, and separation and examination of anions of the fourth and fifth groups. The above experiment items are those which produced the highest level of wastewater.
Taking National Pingtung University of Science and Technology as an example. By using the modified content of experiment items which was suggested to reduce the production amount of experimental wastewater of General chemistry experiment to be 43.21% ; 32.2% for Organic chemistry experiment ; and 35.54% for Analytic experiment. As for Department of Chemical Technology at National Pingtung Senior Industrial Vocational School, by using the improved content of experiment items which was suggested to reduce the production amount of experimental wastewater, space 32.1% for General chemistry experiment can be reduced wastewater; it was 43.82% for Organic chemistry experiment ; spaceand 33.83% for Analytic experiment . The purpose of this thesis is to reduce the cost of waste treatment.
If all the colleges, universities, senior high schools, and vocational high schools in Taiwan can replace the original content of experiment items as our proposed content by reducing the usage amount of chemicals medicine, changing the numbers of groups, changing experiment procedures, and demonstrating in the future, it will reduce the generation amount of experimental wastewater effectively, there will be about 752 ton per year.