To see the other types of publications on this topic, follow the link: Colorimetric method.
Dissertations / Theses on the topic 'Colorimetric method'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 39 dissertations / theses for your research on the topic 'Colorimetric method.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Olsson, Hanna. "Smartphone-based Colorimetric Diagnosis : DEVELOPMENT OF A METHOD FOR AUTOMATIC COMPENSATION OF IMPACT OF LIGHT SETTING." Thesis, KTH, Skolan för teknik och hälsa (STH), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-173907.
Full textAbstract:
During the last years many mobile health applications have emerged on the market. Most of these collect and compiles physical data that can be followed over time. Now the next generation of health care applications are on their way. With an increasing capacity and high quality sensors, smartphones have the potential to be used as diagnostic tools. Calmark Sweden AB is a company that has developed a smartphone based diagnostic platform for analysis of colorimetric assays integrated on a disposable plastic chip. Their first product, the hilda Neo system is a Point of care test (POCT) for semi quantitative measurement of the biomarker Lac- tate dehydrogenase (LDH). The system consists of a disposable colorimetric LDH test with inte- grated chemical assay, a separate light-box for controlled light conditions and a smartphone appli- cation for image acquisition and test analysis. The purpose of this Master Thesis project was to develop and evaluate a method for smartphone based semi quantitative colorimetric analysis of the hilda Neo LDH test that would work without the light-box in different light settings. The method was to be implementable as an iPhone applica- tion and should be able do correctly determine LDH activity in the four LDH ranges; 0-300, 300- 600, 600-900 and >900 units per litre (U/L). Also, the computed LDH levels among cards run with the same sample were not to have a standard deviation higher than 50 U/L. Two methods based on continuous measurements of the colour stimuli given from the assay site were developed. In both methods, measurements were made by using the iPhone camera for taking an image series following the colour development of the assay over time. The image series was then processed in MATLAB and the LDH level was computed in two different ways. None of the two proposed methods did reach the stated objectives. Neither of the methods gave the correct LDH interval in all evaluation cards and the computed LDH levels had a larger standard deviation then aimed for. However the results indicate that the variation in light settings is not the only factor for the unreached objectives. It is believed that with further studies of the colour proper- ties of the hilda Neo assay and with the continuing development of smartphone technology, it is possible to find a method for smartphone-based colorimetric analysis without having to control the light setting.<br>Under de senaste åren har många hälso-applikationer introducerats på marknaden. De flesta samlar och sammanställer hälso-data som sedan kan följas över tiden. Nu är en ny generation av hälso- applikationer på ingång. Med ökande kapacitet och högkvalitativa sensorer har våra smartphones potential att användas för medicinsk diagnostik. Calmark Sweden AB är ett företag som har utvecklat en smartphone-baserad diagnostisk plattform för analys av kolorimetriska tester i form av plastkort för engångsbruk. Deras första produkt hilda Neo är ett patientnära test för semikvantitativ mätning av biomarkören Lactatdehydrogenas (LDH). Systemet består av det kolorimetriska engångstestet för mätning av LDH, en separat ljus-box för kontrollerade ljusförhållanden och en smartphone applikation för bildtagning och test analys. Målet med detta masterexamensarbete var att utveckla och utvärdera en metod för smartphone- baserad semikvantitativ kolorimetrisk analys av hilda Neo testet som fungerar utan ljus-box i olika ljussättningar. Metoden skulle vara implementerbar som en iPhone applikation och skulle kunna bestämma LDH aktivitet inom fyra intervall; 0-300, 300-600, 600-900 och >900 enheter per liter (U/L). De beräknade LDH nivåerna för kort körda med samma prov skulle inte heller ha en standardavvikelse över 50 U/L. Två metoder baserade på kontinuerlig mätning av provets färgutveckling togs fram. För båda metoderna användes iPhone kameran för att ta en bildserie som följde testets färgutveckling över tiden. Bildserien behandlades sedan i MATLAB och ett LDH värde beräknades med de två olika metoderna. Ingen av de två föreslagna metoderna uppnådde de uppsatta målen. Ingen av metoderna gav rätt LDH intervall för alla kort som användes för utvärdering och de beräknade LDH nivåerna hade en för hög standard avvikelse. Dock indikerade resultaten på att variationer i ljussättningen inte var den enda faktorn som bidrog till de ouppnådda målen. Författaren tror att med fortsatt studerande av hilda Neo testets färgegenskaper och med den fortlöpande utvecklingen av smartphone tekniken, kommer det att vara möjligt att hitta en metod för smartphone-baserad kolorimetrisk analys utan kontrollerad ljussättning.
2
Lui, Manjuan. "Studies in combretaceae : development of a colorimetric microdilution antifungal screen and a computational method for characterisation of phytochemicals." Thesis, University of Strathclyde, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.441880.
Full text
3
Dai, Jianming. "Microwave-assisted extraction (MAE) of neem and the development of a colorimetric method for the determination of azadirachtin related limonoids (AZRL)." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0035/MQ64339.pdf.
Full text
4
Yang, Lixia. "Local investigations of gas-liquid mass transfer around Taylor bubbles flowing in straight and meandering millimetric channels using a colorimetric method." Thesis, Toulouse, INSA, 2017. http://www.theses.fr/2017ISAT0027/document.
Full textAbstract:
Les réacteurs-échangeurs à plaques (HEX) sont une technologie clé en intensification des procédés. Cependant, la plupart des recherches existantes portant sur ce type d'équipement ont été réalisées dans le cas d’écoulements monophasiques. Pour les réactions gaz-liquide, peu d'études ont été conduites. Cette thèse a pour objectif d’étudier localement le transfert de matière gaz-liquide autour de bulles de Taylor en écoulement dans des canaux millimétriques droits et ondulés par une méthode dite colorimétrique. Ceci constitue une étape préliminaire indispensable avant la mise en œuvre de systèmes réactifs diphasiques. Il a d’abord déterminé si une possible accélération du transfert de matière gaz-liquide pouvait avoir lieu en présence de la réaction chimique utilisée. La deuxième phase de ce travail s’est focalisée sur l'étape de formation des bulles de Taylor dans un microréacteur. Ensuite, l'hydrodynamique gaz-liquide a été caractérisée et les effets des coudes sur le mécanisme de transfert de masse ont été étudiés localement dans un canal carré millimétrique ondulé. Enfin, une comparaison rigoureuse a pu être effectuée entre les différentes géométries de canaux (ondulé et droit). Elle a permis de montrer comment et pourquoi une géométrie ondulé permet d’intensifier le transfert de masse gaz-liquide (notamment en terme d’efficacité de transfert). L’ensemble de ces résultats ont conduit à la formulation une loi d'échelle, exprimée en termes de nombres de Sherwood, de Graetz et de Péclet, capable de décrire l'évolution du transfert de matière gaz-liquide en fonction de la position axiale dans le canal et des conditions opératoires mises en œuvre<br>Compact Heat-EXchanger reactors (HEX) are an important part of process intensification technology. However, most of the existed research dealing with such type of equipment has been focused on the application of one-phase reactive flows. For gas-liquid reactions, few investigations have been out carried. This thesis aims at locally studying gas-liquid mass transfer around Taylor bubbles flowing in straight and meandering millimetric channels using a colorimetric method; this is a preliminary step essential before implementing two-phase reactive systems. Firstly, the occurrence of a possible enhancement of the gas-liquid mass transfer by the chemical reaction involved was investigated. Secondly, the gas-liquid mass transfer occurring in Taylor flows right after the bubble formation stage in a microreactor was studied. Thirdly, the gas-liquid hydrodynamics were characterized and the effects of bends on the mass transfer mechanism were locally investigated in a millimetric meandering channel. At last, a rigorous comparison could be made between the meandering and straight channels. It showed how and why the meandering geometry leads to intensify gas-liquid mass transfer. All these findings enabled to formulate a scaling law, expressed in terms of Sherwood, Graetz and Péclet numbers, able to describe the evolution of gas-liquid mass transfer as a function of axial position and operating conditions
5
Slabbert, Chrizaan. "Evaluation and validation of methods to determine parasitemia in malaria cell cultures / Chrizaan Slabbert." Thesis, North-West University, 2008. http://hdl.handle.net/10394/2332.
Full text
6
Dinh, Quang Hung. "Development of a Rapid and Easy Measurement Protocol for Perfluorinated Carboxylic Acids (PFCAs) by a Continuous Flow Analysis." 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/204596.
Full text
7
Kamoi, T. "Developing an optimal method for producing a tearless onion." Diss., Lincoln University, 2008. http://hdl.handle.net/10182/1008.
Full textAbstract:
People experience the irritating tearing and burning sensation of lachrymatory factor (LF, propanthial S-oxide) when cutting or chopping onion bulbs. LF is produced by lachrymatory factor synthase (LFS) specifically from 1-propenyl sulfenic acid, a breakdown product of trans-1-propenyl-L-cysteine sulfoxide (1-PRENCSO) by alliinase. This thesis describes strategies to produce a tearless onion by using RNA interference (RNAi) silencing. To determine whether a gene silencing cassette can silence lfs gene transcripts from onion (Allium cepa L.), a crop recalcitrant to genetic transformation, a gene silencing assessment system was developed by using a model plant as a host for the gene of interest. Tobacco (Nicotiana tabacum) plants transgenic for LFS enzyme activity from onion were first produced by introducing a CaMV 35S-onion-lfs gene construct. These plants were then subjected to a second transformation with an RNAi construct directed against the lfs gene sequence. LFS enzyme activity assay showed that the transgenic plants, containing both the lfs gene and the RNAi construct, had significantly reduced LFS activity. This observation was supported by Western analysis for the LFS protein and further validated by quantitative RT-PCR analysis that demonstrated a significant reduction in the lfs transcript level in the dual transformants. This work demonstrated that the RNAi construct is a suitable candidate for the development of a tearless onion. This model plant RNAi system has wide reaching applications for assessment and targeting of plant secondary pathway genes, from poorly studied or recalcitrant plant species, that are important in pharmacological, food and process industries. The functional RNAi vector identified in the model system was transformed into onion. Endogenous lfs transcript levels were successfully reduced by up to 43-fold in six transgenic lines. In consequence, LFS enzyme activity was decreased by up to 1573-fold and this observation was supported by Western analysis for the LFS protein. Furthermore, the production of the deterrent LF upon tissue disruption was reduced up to 67-fold. Subjective olfactory assessment of silenced lines indicated that the pungent odour given off by the leaf and bulb material was much reduced compared with that of non-transgenic counterparts, and that this was replaced by a sweeter milder onion odour. A novel colorimetric assay demonstrated that this silencing had shifted the 1-PRENCSO breakdown pathway so that by reducing LFS protein, more 1-propenyl sulfenic acid was converted into di-1-propenyl thiosulfinate. A consequence of the raised thiosulfinates levels was a marked increase in the downstream production of a non-enzymatically produced zwiebelane isomer that has never previously been identified, and other volatile compounds, di-1-propenyl disulfides and 2-mercapto-3,4-dimethyl-2,3-dihydrothiophenes, which had previously been reported either in small amounts or had not been detected in onions. These raised volatile sulfur compounds provide an explanation for the unique flavour notes of the LF reduced onion and are predicted to have health benefits akin to those found in garlic. These results demonstrated that silencing of LFS enzyme activity by introducing an RNAi construct directed against the lfs gene sequence simultaneously reduced levels of the deterrent LF and increased the desirable thiosulfinates in onions.
8
Ferraz, Neto José. "Desenvolvimento de metodologia para determinação de matéria orgânica do solo por análise de imagens." Universidade do Estado de Santa Catarina, 2015. http://tede.udesc.br/handle/handle/2313.
Full textAbstract:
Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2017-12-05T12:41:21Z
No. of bitstreams: 1
PGCS15MA124.pdf: 1312847 bytes, checksum: 750d88452b24e573464fff88790dbef6 (MD5)<br>Made available in DSpace on 2017-12-05T12:41:21Z (GMT). No. of bitstreams: 1
PGCS15MA124.pdf: 1312847 bytes, checksum: 750d88452b24e573464fff88790dbef6 (MD5)
Previous issue date: 2015-05-15<br>The soil organic matter (SOM) is formed by a set of chemical compounds which have different decomposition rates and products of these processes result as the main source of sulfur, phosphorus and nitrogen into the soil. Because of its great importance to the ground, it is of utmost importance to quantify MOS content. Its composition consists of carbon (C), hydrogen (H), oxygen (O), nitrogen (N), phosphorus (P) and sulfur (S), among others, it is difficult to determine its content. Most analytical techniques measure only carbon and estimate the MOS by a conversion factor. The study aimed to develop an analytical method for quantification of soil organic matter by means of a colorimetric method based on image analysis. The proposed method used the carbon oxidation process of Walkley-Black methodology and the resulting solutions were inserted into spectrophotometer cells for a smart phone equipped with a digital camera with a CCD detector (charge coupled device) register the images. These were treated with ImageJ software and the image of each solution has been selected from an area in which 100x100p were extracted RGB intensities (Red, Green and Blue colors, designs, especially for 8-bit data). We analyzed the RGB values and its relations with the MOS concentrations, resulting that the RED channel showed the best relationship with the organic matter content. The data were modeled by a linear regression (ARED = 0.1222 MOS - 0.1621; R² = 0.9934 and p <0.05) and it was possible to build a model that relates the color intensity with concentration. The proposed method showed accuracy of approximately 71% using a standard soil sample (LUFA Speyer - type 2.2), similar to the result obtained with the method currently used (Walkley-Black) which was 74%<br>A matéria orgânica do solo (MOS) é formada por um conjunto de compostos químicos que possuem diferentes taxas de decomposição, e os produtos desses processos resultam como fontes principais de enxofre, fósforo e nitrogênio para o solo. Devido a sua grande importância para o solo, é de extrema importância a quantificação do teor da MOS. Como a sua composição consiste em carbono (C), hidrogênio (H), oxigênio (O), nitrogênio (N), fósforo (P) e enxofre (S), dentre outros, torna-se difícil a determinação do seu teor. A maioria das técnicas analíticas mensuram apenas carbono e estimam a MOS por um fator de conversão. A pesquisa teve por objetivo o desenvolvimento de uma metodologia analítica para quantificação de matéria orgânica do solo por meio de um método colorimétrico baseado em análise de imagens. O método proposto utilizou o processo de oxidação de carbono da metodologia Walkley-Black e as soluções resultantes foram inseridas em celas espectrofotométricas para que um smartphone equipado com uma câmera digital, com um detector CCD (charge coupled device), registre as imagens. Estas foram tratadas com o software ImageJ e na imagem de cada solução foi selecionado uma área de 100x100p no qual extraíram-se as intensidades RGB (Red, Green e Blue, modelos de cores, especialmente para dados de 8 bits). Analisou-se os valores RGB e suas relações com as concentrações de MOS, resultando que o canal RED apresentou a melhor relação com o teor de matéria orgânica. Os dados foram modelados por meio de uma regressão linear (ARED = 0,1222 MOS – 0,1621; R² = 0,9934 e p < 0,05) e assim foi possível a construção de um modelo que relaciona a intensidade de cor com a concentração. O método prposto apresentou exatidão de aproximadamente 71% usando uma amostra de solo padronizada
(LUFA Speyer – tipo 2.2), similar ao resultado obtido com o método usado atualmente (Walkley-Black) que foi de 74%
9
Barrios, Marco Rogério. "Contribuição à automação do processo de flotação do fosfato de cajati." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/3/3134/tde-18082016-081606/.
Full textAbstract:
Flotação é uma operação unitária à base de química de superfície que envolve a captura de partículas hidrofóbicas por bolhas de ar na suspensão aquosa, na qual são transportadas para a superfície, com posterior remoção desta camada de espuma. Por outro lado, porque as partículas hidrofílicas não aderem a bolhas de ar, elas tendem a afundar e ir para o fluxo inferior do tanque de flotação. A separação de apatita-ganga através de flotação de espuma é o controle eficaz dos fenômenos de molhabilidade, que, por sua vez, determina a seletividade do processo. A regulação da interação de minerais (apatita e ganga) com moléculas de água (natureza hidrofílica) e também com as bolhas de ar (natureza hidrofóbica) é conseguida com a adição de reagentes químicos (coletores, modificadores e espumantes) na polpa de flotação. Adsorção de reagentes químicos na interface mineral/solução é o método mais eficaz para promover a hidrofobicidade das partículas de apatita (favorecendo sua flotação) e também reforçar a hidrofilicidade dos minerais de ganga, inibindo sua flotação. Este trabalho tem o objetivo de construir uma curva de calibração para o coletor Berol®867 através do método colorimétrico de Bradford, método na presença do corante Coomassie Brilliant Blue. Medidas simulando condições típicas de flotação foram também realizadas em laboratório. Medições em soluções de flotação foram realizadas pelo tensiômetro IP6000 que baseia-se no método da pressão máxima de bolha (MPMB) na qual é muito mais adequado para líquidos puros, mas não para soluções aquosas contendo surfactantes. Por conseguinte, os valores de L/G obtidos por MPMB são deterministicamente superiores aos gerados pelo Método com Wilhelmy (MPW), que é considerada como sendo adequada para soluções contendo tensioativos, mas não suficientemente robusta para aplicações industriais in-situ.<br>Froth flotation is a chemistry-based surface unit operation that involves the capture of hydrophobic particles by air bubbles in aqueous slurry, followed by levitation and collection in a froth layer. Conversely, because hydrophilic particles do not adhere to air bubbles, they are likely to sink and go to the underflow of the flotation cell. The selectivity of apatite-gangue separation via froth flotation is determined by the efficient control of the wetting phenomena. Adding chemical reagents to the flotation pulp, like collectors or frothers, it is possible to regulate the interfacial affinity of each mineral, apatite or gangue, turning them hydrophilic or hydrophobic. Adsorption of chemical reagents onto interfaces is the most effective approach to promote the hydrophobicity of the mineral, which is desired to float, and also the reinforcement of the wettability by water of the minerals which are desired to sink. This work had as objective to construct a calibration curve for the Berol®867 collector through the Bradford colorimetric method in the presence of Coomassie Brilliant Blue dye. Measurements simulating typical flotation conditions were also run at the laboratory. Measurements of flotation solution performed by tensiometer IP6000 are based on the Maximum Bubble Pressure Method (MBPM) which is very suitable for pure liquids, but not for aqueous solutions containing surfactants. Therefore, the values of ?LG yielded by MBPM are deterministically higher than those yielded by the Wilhelmy Plate Method (WPM), which is regarded as suitable for surfactant solutions but not sufficiently robust for in-situ industrial applications.
10
Silva, Mariana Rosa da. "Padronização de método colorimétrico para avaliação de atividade biológica de substâncias sobre formas taquizoítas de Toxoplasma gondii, com a avaliação de triterpenos ácidos sobre o parasito." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/60/60135/tde-29052009-154530/.
Full textAbstract:
Toxoplasma gondii é um protozoário pertencente ao filo Apicomplexa, de distribuição mundial, e que infecta diversas espécies hospedeiros, como mamíferos e aves, possuindo como hospedeiros definitivos o gato e outros felídeos, enquanto o homem e outros animais são os seus hospedeiros intermediários. O tratamento é feito, na maioria das vezes, com uma combinação de sulfadiazina e pirimetamina, agindo na via metabólica do ácido fólico, o qual é necessário para a biossíntese de purinas, pirimidinas e certos aminoácidos. Propusemos estabelecer um protocolo de avaliação sobre esse protozoário, assim como padronizarmos uma metodologia por espectroscopia para uma rápida avaliação ou triagem de substâncias potencialmente ativas contra o parasito. Verificamos a atividade das substâncias ácido ursólico e ácido oleanóico, as quais já demonstraram atividade biológica sobre outras espécies de protozoários, como Plasmodium, Trypanosoma cruzi e Leishmania sp. em sistemas in vitro e in vivo. A metodologia colorimétrica pelo MTT, pelo Alamar Blue®, do kit CyQUANT® NF e a contagem manual em meio líquido das formas taquizoítas do parasito em ensaios biológicos in vitro mostram-se inviáveis, pois há grande dificuldade em manter a integridade do parasita em meio de cultura líquido, o qual se mostra sensível à adição de qualquer outro componente que não aqueles necessários para manter sua viabilidade em ambiente extracelular. O ácido ursólico mostrou-se potencialmente ativo in vitro sobre formas intracelulares de T. gondii. Entretanto, o contato de células infectadas com as substâncias avaliadas por um período de 48 horas não resultou em diminuição mais acentuada na porcentagem de células infectadas do que a ocorrida no tratamento de 24 horas. A comparação dos resultados do tratamento pós infecção celular por 24 horas e do pré-tratamento das formas taquizoítas houve diferenças significativas, indicando principalmente maior ação do pré-tratamento sobre T. gondii. Quando administrado na dose de 7 mg/kg/ dia a camundongos infectados, o ácido ursólico não apresentou atividade sobre o parasita.<br>Toxoplasma gondii is an Apicomplexa protozoan, of worldwide distribution, that infects several species, from mammalians to birds; its definitive hosts are the cats and other felines, while man and other animals are considered as intermediate hosts. Treatment is, generally, a combination of sulfadiazine and pyrimethamine, triggering the metabolic pathway of folic acid, which is necessary for certain purines, pirimidines and aminoacids biosynthesis. We have proposed an evaluation protocol on this protozoan, and also to establish a methodology by spectroscopy for rapid evaluation of pottentialy bioactive substances against the parasite. The ursolic acid and oleanoic acid bioactivity were tested. These substances have already demonstrated to be effective on another protozoan species, like Plasmodium, Trypanosoma cruzi e Leishmania sp., either in vitro or in vivo. The colorimetric methodology by MTT, Alamar Blue®, CyQUANT® NF kit and manual counting of tachyzoite forms in liquid culture medium showed to be unviable, because there is a great difficult to maintain the parasite viability in liquid culture medium, wich one is sensible to addition of any other component different of that necessary for its survival in extracelular ambient. Ursolic acid was pottentialy active on T. gondii intracellular forms. However, the infected cells in contact with the tested substances for a period of 48 hours did not show a statistical greater reduction as compared to infected cells which underwent treatment for 24 hours. Significant results were observed when comparing pre-treatment of tachyzoite forms and treatment for 24 hours post-cellular infection. Our data pointed in the direction that pre-treatment exerted a higher effectiveness. Any parasiticidal activity was observed when ursolic acid on a concentration of 7 mg/kg/day was administered to infected mice.
11
Martins, Luciana Foltram. "Desenvolvimento de equipamento de baixo custo instrumentalizar o metodo ASTM D 1209-00." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/250214.
Full textAbstract:
Orientadores: Adriana Vitorino Rossi, Matthieu Tubino<br>Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica<br>Made available in DSpace on 2018-08-11T04:54:42Z (GMT). No. of bitstreams: 1
Martins_LucianaFoltram_M.pdf: 1935744 bytes, checksum: f05f16f5c0380e513d0ae7b7af183efe (MD5)
Previous issue date: 2008<br>Resumo: O método ASTM D 1209-00 descreve o procedimento para a medida visual da coloração de líquidos levemente coloridos, que envolve a comparação visual entre a coloração de amostras com a coloração de padrões Pt-Co com concentração variando de 1 a 500 na escala do ASTM D 1209-00 (soluções obtidas pela mistura de cloroplatinato de potássio, com concentração na faixa de 1,5x10 a 3,6x10 mol L e cloreto de cobalto hexahidratado nas concentrações de 1,7x10 a 4,2x10 mol L). Sabe-se e foi constatado em teste com voluntários, que há grandes dificuldades de aplicação para as soluções mais diluídas (soluções de concentração 1 a 25 unidades de Pt-Co), que são extremamente claras, de difícil distinção em observações visuais e, em muitos casos, representam as amostras de maior interesse em alguns setores de aplicação. Na tentativa de superar essas dificuldades, desenvolveu-se um equipamento robusto e de baixo custo para análises rápidas. Foi utilizado um diodo emissor de luz (LED) azul como fonte de radiação e um fotodiodo com CI S7183 (Hamamatsu) como detector num conjunto de celas de PVC preto com diferentes opções de caminho óptico e com a opção de uso de tubo de vidro interno para conter as soluções. Foram obtidas curvas analíticas com ajuste de segundo grau com as celas de 340 e 170 mm. Com cela de 85 mm foi obtida curva analítica linear com coeficiente de correlação = 0,9978 entre 25 e 500 unidades de Pt-Co. Com o uso de um tubo de vidro obtiveram-se curvas com ajuste polinomial de segunda ordem com as celas de 170 e 85 mm. Para testar o desempenho do dispositivo desenvolvido, foram utilizadas amostras de bisfenol epóxi, hidroperóxido de cumeno, ácido salicílico em etanol e em solução aquosa de carbonato de sódio 10 % m/v e ciclohexanol. Os resultados apresentaram desvios da ordem de ±1 unidade de Pt-Co, mais precisos do que o método ASTM que apresenta desvios de até ±4 unidades de Pt-Co; com relação à exatidão, houve diferença estatística ao nível de 95 %, o que pode remeter a problemas com o método de referência<br>Abstract: The ASTM D1209-00 method describes the procedure for the visual measurement of the color of essentially light colored liquids, which involves the visual comparation between the color of the samples with the color of Pt-Co standards solutions, with concentration from 1 to 500 unities of Pt-Co, the ASTM D 1209-00 scale (solutions obtained by mixing potassium chloroplatinate, from 1,5x10 to 3,6x10 mol L and cobalt chloride in the concentrations of 1,7x10 to 4,2x10 mol L). It is kown and was confirmed in tests with volunteers that there and serious difficulties with this method for very diluted solutions (concentration from 1 to 25 unities of Pt-Co), that are extremely clear, hardly distinguished by visual observation, whose in many cases represent the samples of most interest in some application sectors. In an attempt to overcome these difficulties, a robust and low cost device was developed for a rapid analysis. A blue light emitting diode (LED) was used as a radiation source and a Photo IC Diode S7183 (Hamamatsu) as the detector, in a set of black PVC cells with different options of optical path and with the option of using or not an internal glass tube to load the solutions. Analytical curves were obtained with second degree fitting for 340 and 170 mm cells. An 85 mm cell gives linear analytical curve with correlation coefficient = 0.9978, from 25 to 500 units of Pt-Co. With the use of the glass tube, curves with second order polynomial fitting were obtained for 170 and 85 mm cells. The performance of the device developed were tested with samples of epoxy bisfenol, cumene hidroperoxide, salicilic acid in ethanol and in aqueous solution of sodium carbonate 10 % w/v and cyclohexanol. The results presented deviations of the order of ± 1 units of Pt-Co, more precises than the ASTM method, which presents deviations up to ± 4 units of Pt-Co; with respect to the accuracy, there was statistic difference at the level of 95 %, which can be related to problems with the reference method<br>Mestrado<br>Quimica Analitica<br>Mestre em Química
12
North, Amy D. "Investigation of observer variability using a new method for determining color matching functions /." Online version of thesis, 1991. http://hdl.handle.net/1850/11099.
Full text
13
Petersen, Kelvin H. "An investigation of new methods to improve the accuracy of some modern color spectrophotometers /." Online version of thesis, 1989. http://hdl.handle.net/1850/11548.
Full text
14
Miwa, Adriana Cristina Poli. "Comparação e avaliação dos métodos colorimétricos utilizados para determinação de proteínas em lagoas de estabilização." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-17042006-142148/.
Full textAbstract:
As lagoas de estabilização representam um dos métodos mais simples utilizados para tratamento de esgoto sanitário. Grande parte da matéria orgânica presente no esgoto sanitário é constituída por proteínas, a qual torna-se fator limitante aos processos biológicos de tratamento de águas residuárias em que se encontram presentes. O objetivo deste trabalho foi avaliar e comparar métodos colorimétricos para determinação de proteínas, definindo qual é o mais apropriado para esse tipo de ambiente. Os métodos colorimétricos utilizados foram o de Lowry, de Bradford, do Biureto e do Ácido Bicinconínico. As proteínas padrões utilizadas foram soroalbumina, caseína e ovoalbumina. O método de Bradford apresentou várias desvantagens. Biureto I e III e proteína bruta medida a partir do Nitrogênio Total Kjeldah (NTK) apresentaram valores altos devido não medir somente proteínas. A quantidade de proteínas na amostra não foi suficiente para que ocorresse reação no método Biureto II. O método do Ácido Bicinconínico não reagiu com caseína e o custo do reagente é alto. Portanto, o método apropriado para esse tipo de amostra foi o Lowry que apresentou maior reprodutividade e sensitividade. Para comprovar esse resultado, uma análise de adição de padrão à amostra foi realizada para verificar se haviam substâncias interferentes, cujo resultado foi negativo<br>Stabilization ponds represent a simple method to treat sanitary sewage. A large part of the organic matter present in sanitary sewage consists of proteins, which become a limiting factor for the wastewater treatment in biological processes. The goal of this work was to evaluate and to compare colorimetric methods for protein determination, defining which is the more appropriate for this environment. The colorimetric methods used were the Folin-phenol, Bradford, Biuret and Bicinconinic Acid methods. The protein standards used were serum albumin bovin, casein and ovalbumin. The Bradford method introduced several disadvantages. Biuret I and III and brute protein introduced high values due don't measure only proteins. The proteins quantity in the sample wasn't enough so that it had occurred reaction in the Biuret II method. The method of Bicinconinic Acid didn't react with casein and the reagent cost is high. Therefore, the method appropriated for this sample was the Lowry that introduced larger reprodutivity and sensitivity. To prove this result, a standard addition analysis was performed to verify if there were interfering substances, whose result was negative
15
Peters, Kelley L. "Development of Presumptive and Confirmatory Analytical Methods for the Simultaneous Detection of Multiple Improvised Explosives." FIU Digital Commons, 2014. http://digitalcommons.fiu.edu/etd/1659.
Full textAbstract:
In recent years, there has been a dramatic increase in the use of improvised explosive devices (IEDs) due to ease of synthesis and improved controls placed on commercial/military explosives. Commonly used materials for IED preparations include fertilizers and industrial chemicals containing oxidizers such as ClO3-, ClO4-, and NO3-, as well as other less stable compounds, such as peroxides. Due to these materials having a wide range of volatility, polarity, and composition, detection can be challenging, increasing the amount of time before any analytical information on the identity of the explosive can be determined. Therefore, this research project developed two analytical methods to aid in the rapid detection of multiple explosive compounds.
The use of microfluidic paper-based analytical devices (µPADs) allows for the development of inexpensive paper devices utilizing colorimetric reactions, which can perform five or more simultaneous analyses in approximately five minutes. Two devices were developed: one for the detection of inorganic explosives including ClO3-, ClO4-, NH4+, NO3-, and NO2-, and the second device detects high/organic explosives including RDX, TNT, urea nitrate, and peroxides. Limits of detection ranged from 0.4 µg – 20 µg of explosive residue with an analysis time of less than five minutes.
Development of a confirmatory method utilizing infusion electrochemical detection-electrospray ionization-time-of-flight mass spectrometry (EC-ESI-TOF MS) and 18-crown-6 ethers to produce guest/host complexes with inorganic ions has also been completed. Utilizing this method the inorganic ions present in many IEDs can be successfully detected as ion pairs, while still allowing for the detection of other high explosives1. Placing an electrochemical detector before the mass spectrometer permits the detection of hydrogen peroxide, an analyte normally difficult to detect through mass spectrometry. Limits of detection ranged from 0.06 ppm - 2 ppm with an analysis time of less than two minutes.
The development of these presumptive and confirmatory analytical methods permits the detection of a wide range of components present in IEDs. These methods decrease the amount of time required to relay information on the type of explosives present by simplifying the analysis process in the field and in a laboratory.
16
Mori, Eva Kaiser. "Caracterização de pinturas do artista Alfredo Volpi por meio de métodos não destrutivos: espectrofotômetro, EDXRF, MEV e imageamento multiespectral." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/44/44144/tde-17112015-151200/.
Full textAbstract:
Alfredo Volpi (1896 - 1988) é um dos mais importantes pintores brasileiros contemporâneos. Sua extensa obra foi marcada, principalmente, por composições cromáticas e abstrações geométricas. Foi um artista que dava importância muito grande à técnica e aos materiais, tendo desenvolvido uma maneira própria e sistemática de trabalhar: confeccionava suas próprias telas, tintas e até pigmentos, com terras naturais. Analisou-se ao todo 11 pinturas a têmpera em diversos suportes (tela, aglomerado de madeira e mural), 10 delas realizadas na década de 1950, período em que a obra do artista passou por uma grande transformação, do figurativismo ao abstracionismo e do uso de tintas industriais à base de óleo para a técnica medieval da têmpera. As características de opacidade, saturação cromática e presença material do pigmento sobre a superfície da tela, inerentes a esta técnica pictórica, tornam-se elementos tão importantes em sua obra, quanto o uso da cor na formação do espaço. Foram realizados estudos de cor e composição química dos materiais e levantamentos de informações sobre seus procedimentos técnico-artísticos a partir de métodos analíticos complementares não destrutivos e pesquisa em diversas fontes, pois entende-se que estes elementos são chaves importantes para o entendimento mais profundo de sua obra. O espectrofotômetro foi utilizado para medição da cor com base em curvas espectrais e coordenadas numéricas de referência dentro de um espaço de cor uniforme. Técnicas de imageamento por luz visível, fluorescência visível por radiação ultravioleta e reflectografia de infravermelho próximo foram utilizadas para levantar informações sobre o processo criativo do artista, detectar locais de intervenções de restauro e observar o grau de fluorescência de cada área cromática das pinturas como auxiliar na identificação de pigmentos. A técnica de EDXRF (Espectroscopia de Fluorescência de Raios X por Energia Dispersiva) foi importante para caracterização química dos materiais. O MEV-EDS (Microscópio Eletrônico de Varredura com Espectroscopia por Dispersão de Energia de Raios X) forneceu informações sobre composição química e imagens da superfície dos materiais presentes nas pinturas murais. A partir da integração destas informações pôde-se identificar uma parte da rica paleta deste pintor, documentar as cores das pinturas no presente, identificar ou dar indicações da composição dos pigmentos e da base de preparação das pinturas e iluminar partes da história de cada uma das obras, como presença de esboços feitos à grafite, pinturas anteriores encobertas, pinceladas e maneiras de misturar a tinta e documentar seu estado atual de conservação. As ferramentas utilizadas se mostraram úteis na caracterização das pinturas, revelaram informações inéditas sobre a obra deste artista e levantaram novas indagações. As informações obtidas podem ser o início de um banco de dados sobre sua obra.<br>Painter Alfredo Volpi (1896 - 1988) is one of the most important contemporary Brazilian artists. His extensive work, mostly characterised by chromatic compositions and geometric abstractions, is technically unique. The artist attributed great importance to craft and materials, developing his own systematic way of working. Among the paintings analysed were 11 temperasin various supports (canvas, hardboard panel and mortar). Of the selection, 10 paintings were made around 1950, when the artist\'s work underwent a major transformation, from figuration to abstraction, from the use of industrial oil-based paints to the medieval technique of tempera. This technique, known for its opacity, colour saturation and material presence of pigments on the canvas,became as important as the colour itself in the shaping of the artist\'s new spatial relation. It is understood that these elements are important keys to a deeper understanding of his work, both technically and artistically. The present investigation was carried out making use of non-destructive complementary analytical techniques. The aim was to study the chromatic and chemical composition characteristics of his paintings and gather information on the technical procedures the artist may have used. The spectrophotometer was used to measure the colour based on the spectral curves and numerical reference coordinates within a uniform colour space. Techniques of visual examination with visible light, visible fluorescence by ultraviolet radiation and near-infrared reflectography were used to gather information about the artist\'s creative process. These techniques also helped detect restoration patches and identify pigments. The EDXRF (Energy Dispersive X-Ray Fluorescence) technique was important for chemical characterization of materials, while the SEM-EDS (Scanning Electron Microscope with Energy Dispersive X-Ray Spectroscopy) provided surface images and information on the chemical composition of the material present in the murals. From the integration of these techniques it was possible to identify a part of the rich palette of Volpi´s paintings; to document the present aspects of the colours; to recognize or give indications of pigment and ground compositions and to shed light on parts of each of the works background, such as the presence of graphite sketches, covered earlier paintings and brushstrokes as well as to document the current condition of the works under study. The tools used have proven useful in characterizing the paintings, revealing new information about the work of the artist and raising new questions. The information obtained may be the beginning of a database on his oeuvre.
17
Mizumoto, Camilo [UNESP]. "Investigação da reação álcali-agregado (RAA) em testemunhos de concreto e agregados constituintes." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/91463.
Full textAbstract:
Made available in DSpace on 2014-06-11T19:25:21Z (GMT). No. of bitstreams: 0
Previous issue date: 2009-06-29Bitstream added on 2014-06-13T20:32:50Z : No. of bitstreams: 1
mizumoto_c_me_ilha.pdf: 6141199 bytes, checksum: d708c1fab69dfe7948269a1d6ffae9a2 (MD5)<br>Fundação de Ensino Pesquisa e Extensão de Ilha Solteira (FEPISA)<br>A reação álcali-agregado (RAA) é um fenômeno expansivo que ocorre em diversas estruturas de concreto que vivenciam freqüentes condições de umidade. O princípio desta reação fundamenta-se em interações químicas entre a sílica constituinte do agregado e os álcalis presentes no concreto, em presença de umidade. O produto formado é um “gel” expansivo que ocasiona processos de fissuração e deslocamentos diferenciais em estruturas de concreto. Atualmente, vários centros de pesquisa têm estudado diversas formas de diagnosticar a presença da reação em estruturas degradadas e avaliar previamente o potencial reativo dos agregados empregados nas obras civis. Os métodos comumente empregados na avaliação da RAA envolvem ensaios laboratoriais normalizados pela NBR 15577 (ABNT, 2008) e técnicas qualitativas de campo. Dentre estas técnicas destaca-se o teste da mancha, que identifica a presença da reação de forma imediata pela formação de tonalidades características em regiões afetadas do concreto. Neste contexto, a presente pesquisa objetivou investigar a RAA em testemunhos de concreto e em diferentes litologias de agregado por análises laboratoriais e técnicas qualitativas. No trabalho desenvolvido foi estudada a composição físico-química de produtos extraídos da RAA e dos materiais componentes dos testemunhos, além de estudos da reatividade potencial dos agregados constituintes por análises mineralógicas e ensaios acelerados de argamassa e concreto, sendo complementados por estudos microestruturais e testes qualitativos (método da mancha). Os resultados mostraram a diversidade na composição de xerogéis da RAA e incompatibilidades nos resultados dos ensaios de reatividade em agregados. Os testes colorimétricos apresentaram um desempenho satisfatório no indicativo da RAA, além de distinguir a presença de outras manifestações patológicas nos concretos e compósitos estudados<br>The alkali-aggregate reaction (AAR) is an expansion phenomenon that occurs in diverse concrete structures that live in frequently conditions of humidity. The principle of this reaction is based on chemical interactions between the constituent yield of the aggregate and the alkalis of the concrete, in humidity presence. The created product is an expansion gel that generates processes of cracking and differential displacements in concrete structures. Nowadays, many research centers have studied diverse forms to diagnose the presence of the reaction in degraded structures and to previously evaluate the potential reactivity of aggregates used in civil buildings. The common methods used in the evaluation of the RAA involved laboratory assays normalized by NBR 15577 (ABNT, 2008) and qualitative techniques of yield. Among these techniques, the staining method detached which identifies the presence of the reaction of immediate form for the formation of characteristic shade in affected regions of the concrete. In context, the present research objectified to investigate the AAR in concrete core and different lithology of aggregate, being approached laboratory assays and qualitative techniques. It was studied the composition physical-chemistry of extracted products of the AAR and the component materials of concrete core, besides studies of the potential reactivity of constituent aggregates for mineralogical assays and mortar bar test and concrete prisms. Also complemented by microstructure studies and qualitative tests (staining method).The results showed diverseness composition of xerogels of the AAR and incompatibilities in the results of the reactivity assays in aggregates. The staining tests showed satisfactory performances in the indicative of the AAR with regard of the presence of other pathological manifestations in concrete and cement composites
18
Mizumoto, Camilo. "Investigação da reação álcali-agregado (RAA) em testemunhos de concreto e agregados constituintes /." Ilha Solteira : [s.n.], 2009. http://hdl.handle.net/11449/91463.
Full textAbstract:
Orientador: Antonio Anderson da Silva Segantini<br>Banca: Selmo Chapira Kuperman<br>Banca: Marcelo Ornaghi Orlandi<br>Resumo: A reação álcali-agregado (RAA) é um fenômeno expansivo que ocorre em diversas estruturas de concreto que vivenciam freqüentes condições de umidade. O princípio desta reação fundamenta-se em interações químicas entre a sílica constituinte do agregado e os álcalis presentes no concreto, em presença de umidade. O produto formado é um "gel" expansivo que ocasiona processos de fissuração e deslocamentos diferenciais em estruturas de concreto. Atualmente, vários centros de pesquisa têm estudado diversas formas de diagnosticar a presença da reação em estruturas degradadas e avaliar previamente o potencial reativo dos agregados empregados nas obras civis. Os métodos comumente empregados na avaliação da RAA envolvem ensaios laboratoriais normalizados pela NBR 15577 (ABNT, 2008) e técnicas qualitativas de campo. Dentre estas técnicas destaca-se o teste da mancha, que identifica a presença da reação de forma imediata pela formação de tonalidades características em regiões afetadas do concreto. Neste contexto, a presente pesquisa objetivou investigar a RAA em testemunhos de concreto e em diferentes litologias de agregado por análises laboratoriais e técnicas qualitativas. No trabalho desenvolvido foi estudada a composição físico-química de produtos extraídos da RAA e dos materiais componentes dos testemunhos, além de estudos da reatividade potencial dos agregados constituintes por análises mineralógicas e ensaios acelerados de argamassa e concreto, sendo complementados por estudos microestruturais e testes qualitativos (método da mancha). Os resultados mostraram a diversidade na composição de xerogéis da RAA e incompatibilidades nos resultados dos ensaios de reatividade em agregados. Os testes colorimétricos apresentaram um desempenho satisfatório no indicativo da RAA, além de distinguir a presença de outras manifestações patológicas nos concretos e compósitos estudados<br>Abstract: The alkali-aggregate reaction (AAR) is an expansion phenomenon that occurs in diverse concrete structures that live in frequently conditions of humidity. The principle of this reaction is based on chemical interactions between the constituent ���� yield���� of the aggregate and the alkalis of the concrete, in humidity presence. The created product is an expansion gel that generates processes of cracking and differential displacements in concrete structures. Nowadays, many research centers have studied diverse forms to diagnose the presence of the reaction in degraded structures and to previously evaluate the potential reactivity of aggregates used in civil buildings. The common methods used in the evaluation of the RAA involved laboratory assays normalized by NBR 15577 (ABNT, 2008) and qualitative techniques of ���� yield. Among these techniques, the staining method detached which identifies the presence of the reaction of immediate form for the formation of characteristic shade in affected regions of the concrete. In context, the present research objectified to investigate the AAR in concrete core and different lithology of aggregate, being approached laboratory assays and qualitative techniques. It was studied the composition physical-chemistry of extracted products of the AAR and the component materials of concrete core, besides studies of the potential reactivity of constituent aggregates for mineralogical assays and mortar bar test and concrete prisms. Also complemented by microstructure studies and qualitative tests (staining method).The results showed diverseness composition of xerogels of the AAR and incompatibilities in the results of the reactivity assays in aggregates. The staining tests showed satisfactory performances in the indicative of the AAR with regard of the presence of other pathological manifestations in concrete and cement composites<br>Mestre
19
Guglielmino, Maud. "Développement d'une nouvelle méthode analytique du formaldéhyde dans l'air basée sur un dispositif microfluidique." Thesis, Strasbourg, 2014. http://www.theses.fr/2014STRAF048.
Full textAbstract:
Le formaldéhyde (HCHO) est un polluant majeur de l’air intérieur. L’objectif de cette thèse est de réaliser les avancées scientifiques et technologiques nécessaires à l’obtention d’une méthode analytique basée sur un dispositif microfluidique de mesure du formaldéhyde dans l’air associant précision, sélectivité, rapidité d’analyse avec pour objectif majeur une autonomie suffisante sur de longues durées, typiquement un mois. Le principe de la méthode reposait initialement sur trois étapes clés, à savoir le piégeage du formaldéhyde gazeux en solution, la réaction du formaldéhyde avec un agent dérivatif, puis la détection du produit de dérivation par colorimétrie ou fluorimétrie. La méthode a finalement évolué vers seulement deux étapes distinctes grâce à l’utilisation d’un dispositif microfluidique innovant dans lequel le piégeage et la réaction ont lieu simultanément. L’étude des performances analytiques du dispositif a permis de valider la méthode développée pendant cette thèse<br>Formaldehyde (HCHO) is a major pollutant in indoor air. The objective of this work is to realize the scientific and technological advances required to obtain an analytical method based on a microfluidic device to measure air formaldehyde combining precision, selectivity, analysis speed with for major objective a sufficient autonomy on a long time, typically one month. The principle of the method was initially based on three key steps, the gaseous formaldehyde uptake in solution, the formaldehyde derivatization reaction, then the detection of reaction product by colorimetry or fluorimetry. The method has finally advanced toward only two definite steps thanks to the use of an innovative microfluidic device in which uptake and reaction take place simultaneously. The study of analytical performances of the device allows to validate the method developedduring this work
20
Van, Houwelingen ArJan. "Liquid-solid contacting in trickle-bed reactors." Thesis, University of Pretoria, 2009. http://hdl.handle.net/2263/30008.
Full textAbstract:
Several types of reactors are encountered in industry where reagents in a gas and a liquid phase need to be catalysed by a solid catalyst. Common reactors that are used to this end, are trickle-bed reactors, where gas and liquid flow cocurrently down a packed bed of catalyst. Apart from the catalytic process itself, several mass transfer steps can influence the rate and/or selectivity of a solid catalysed gas-liquid reaction. In trickle-bed reactors, flow morphology can have a major effect on these mass transfer steps. This study investigates the interaction between liquid flow morphology and mass transfer in trickle-bed reactors from three different angles. The primary focus is on liquid-solid mass transfer and internal diffusion as affected by the contacting between the liquid and the catalyst. First, the contacting between the liquid and the solid in trickleflow, or wetting efficiency, is characterised using colorimetry. Though this investigation is limited to the flow of nitrogen and water over a packed bed at ambient conditions, it provides useful information regarding liquid flow multiplicity behaviour and its influence on the distribution of fractional wetting on a particle scale. The colorimetric study also provides descriptions of the geometry of the liquid-solid contacting on partially wetted particles. These are used in a second investigation, for the numerical simulation of reaction and diffusion in partially wetted catalysts. This second investigation uses numerical simulations to evaluate and develop simple theoretical descriptions of liquid-solid contacting effects on catalyst particle efficiency. Special attention is given to the case where external and intraparticle mass transfer rates of both a volatile and non-volatile reagent affect the overall rate of reaction. Also, since these are not often considered in theoretical studies, some suggestions are made for the evaluation of the particle efficiency of eggshell catalyst. Finally, liquid-solid contacting is investigated in a high-pressure pilot reactor. Wetting efficiency is measured with a useful technique that does not rely on descriptions of particle kinetics or liquid-solid mass transfer rates. Liquid-solid mass transfer coefficients are also measured and results agree well with the colorimetric investigation, suggesting the existence of different types of flow within in the hydrodynamic multiplicity envelope of trickle-flow. Since it consists of different investigations of liquid-solid contacting from different angles, the study highlights several aspects of liquid-solid contacting and how it can be expected to influence trickle-bed reactor performance.<br>Thesis (PhD)--University of Pretoria, 2009.<br>Chemical Engineering<br>unrestricted
21
Borghetti, Alice. "Effetto della modalità e del tempo di cottura su alcuni caratteri fisici ed analitici del cardo di Cervia." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/19282/.
Full textAbstract:
Il cardo è un ortaggio della tradizione agricola cervese caratterizzato dall’inconfondibile sapore dolce, che lo contraddistingue da altri prodotti simili, dovuto al suo storico metodo di coltivazione. L’obiettivo di questo elaborato è stato verificare l’effetto di due diverse metodologie di cottura, quali bollitura e cottura a vapore, e l’effetto del tempo di cottura su alcuni caratteri qualitativi in campioni di cardo tipico di Cervia, forniti dall’Azienda Agricola Giuseppe Fiori di Pinarella di Cervia (Ravenna). I caratteri qualitativi considerati sono stati: variazione di peso, consistenza, caratteri colorimetrici, contenuto di composti fenolici e attività antiossidante. I polifenoli totali sono stati soggetti ad una variabilità abbastanza alta, soprattutto nella cottura a vapore in cui l’andamento risulta variabile in funzione del tempo, mentre per la bollitura l'andamento è risultato regolarmente decrescente in funzione del tempo. E’ stato anche possibile stabilire l’effetto dei trattamenti sull’attività antiossidante e la relazione di questa con il quantitativo di polifenoli totali, che è risultata elevata e altamente significativa. Dalle analisi condotte non è stata riscontrata una differenza sostanziale del contenuto di polifenoli totali rispetto a quanto riportato in letteratura, pertanto possiamo individuare un quantitativo medio di polifenoli totali, nel cardo crudo, di circa 1000-2000 mg acido gallico / kg t.q. Dallo studio non è stato osservato un effetto significativo del metodo di cottura sulla consistenza del prodotto cotto, che è invece variato significativamente in funzione del tempo. Dallo studio effettuato è possibile ipotizzare che i valori di grado tenderometrico corrispondenti a maggiore accettabilità sensoriali siano compresi fra 80 e 140, ottenuti per tempi di cottura compresi tra 5 e 15 minuti; per tempi di cottura superiori il prodotto perde consistenza, mentre per tempi inferiori il cardo potrebbe risultare troppo duro.
22
Dias, Liliana Sofia Ribeiro. "Optimization of a colorimetric method for determination of fluoride in saliva." Dissertação, 2012. https://repositorio-aberto.up.pt/handle/10216/87917.
Full text
23
Dias, Liliana Sofia Ribeiro. "Optimization of a colorimetric method for determination of fluoride in saliva." Master's thesis, 2012. https://repositorio-aberto.up.pt/handle/10216/87917.
Full text
24
Hwang, Kuan-Luen, and 黃冠綸. "Interference Study of the Colorimetric Method for the Determination of Dissolved Oxygen in Seawater." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/93641270020129813057.
Full textAbstract:
碩士<br>國立臺灣大學<br>海洋研究所<br>94<br>Four potential interference factors involved in colorimetric determination of dissolved oxygen were studied. Those factors include the concentrations of oxygen and iodide in the sample and reagent, the wavelength and temperature at which the detection is made. Evaluations were made both theoretically and experimentally on the linearity of the calibration curve. The results show that concentrations of dissolved oxygen and iodide cause variation of the ratio between molecular iodine and tri-iodide, thus leading to a bending phenomenon of the calibration curve. Detection made at near the isobestic point (466~469 nm) may reduce the above interference at the cost of losing up to 30% of the sensitivity. The colorimetry can be carried out at 456 nm but it is important to ensure a high strength of iodide reagent (e.g. the final strength = 33 mM) so as to minimize the bending effect. The temperature of the sample is found essential because it alters the spectrum of the final color and causing a shift of the isobestic point (ca. 0.5 nm per 5 oC). The shifting is more significant at a relatively higher wavelength. In conclusion, when the final temperature is to be controlled within a ±1 oC error and the iodide reagent strength is sufficient, the colorimetric approach can provide a precise and reliable tool for the determination of oxygen at the naturally occurring concentration range (up to 300 μM) in the ocean environment.
25
Eriksson, Louise. "Validation of a colorimetric method for determination of fructosamine in plasma usingMindray BS-380." Thesis, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-349084.
Full textAbstract:
HbA1c and glucose are the most widely used indicators for glucose control, but they havesome disadvantages. Improving the diagnosis of diabetes is always ongoing, other markersare needed as a complement when standard measurements are not sufficient. One alternativeis analysis of fructosamine, which is commercially available and inexpensive.The main aim with this study was to validate a colorimetric method for analyzingfructosamine including investigation of precision, linearity and stability. Fructosamine valueswas compared with HbA1c values with and without genetic variations in the hemoglobingene. An investigation on if serum albumin concentration affects fructosamine values wasalso performed. The colorimetric method was also compared with an enzymatic method foranalysis of frutcotsamine.Blood samples were analyzed as HbA1c on Cobas 6000 c501 and for analysis of thegenetic variants Capillarys 3 TERA was used. Plasma was collected and analyzed onMindray BS-380 as fructosamine and albumin.The methods in this study were comparable and the colorimetric method had greatprecision and linearity. The correlation between HbA1c and fructosamine was R2= 0,402.Fructosamine was not affected by genetic variations in the hemoglobin molecule and may bea useful indicator of high glucose and could replace analysis of HbA1c. Fructosamine wasnot affected by albumin. The enzymatic method was shown to correlate better with HbA1cthan the colorimetric method.In conclusion, analyzing fructosamine could be an alternative to HbA1c when patientshave genetic variants and would improve the glycemic control.
26
Wang, Tzu-Pao, and 王子豹. "The Influence on Different Voltages of Accelerated Chloride Migration Test by Using Colorimetric Method." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/41931470175376726852.
Full textAbstract:
碩士<br>國立臺灣海洋大學<br>材料工程研究所<br>94<br>Abstract
The accelerated chloride migration test was used to investigate the different voltages (24V, 30V, and 48V), different w/b ratios (0.35, 0.45, 0.55, and 0.65) ,different ages (28days, 91days) and the ordinary Portland cement concrete and concrete containing different type of mineral admixtures (fly ash, slag and ash with slag replacement for 20%, 40% and 30% weight of the total cementitious content) effect of the total charge passeds in concrete. The colorimetric method test was used to measure the chloride ion penetration depth in specimen of concrete and calculate chloride ion non-steady-state migration coefficient. Than finally to proceeding the usage of probability by taking advantage of the character of random inaccuracy in statistics.
Speaking about age, the migration coefficient of the chloride ion non-steady-state resulted from 91 days was more lower than 28 days; comparing the controlled set (C set) with contrastive set (F set, S set, SF set), the migration coefficient of the chloride ion non-steady-state is C set > S set > SF set > F set.
In process of ACMT and colorimetric method, we can find out that when specimen in a state of 48V with age 28 days, its energy will be more higher resulted from more higher voltage during the same electricized time. The electric current will generate heat resulted from high resistance of concrete when it penetrates specimen, the moving ratio of chloride will be faster resulted from increased temperature. Hence when voltage is more higher, it will resulted in entire penetration through concrete specimen by much of specimen that will cause us enable to evaluate. Moreover the waterization of age 28days’ specimen not yet completed that resulted in incompact construction of vesicle, and it will
cause chloride to pass quickly if increase the voltage that will probably
cause ruin of concrete construction. So not to take this kind of data on carrying out analysis for other 5 items. If just in consideration of single observely, the graph of standard related deviation that the total charge passeds of unit area and the chloride average penetration depth will achieve requests from the control curve.
Keywords: Accelerated chloride migration test, Colorimetric method, Chloride migration coefficient
27
"Novel Colorimetric Sensors with Extended Lifetime for Personal Exposure Monitoring." Doctoral diss., 2019. http://hdl.handle.net/2286/R.I.55643.
Full textAbstract:
abstract: Air pollution has been linked to various health problems but how different air pollutants and exposure levels contribute to those diseases remain largely unknown. Researchers have mainly relied on data from government air monitoring stations to study the health effects of air pollution exposure. The limited information provided by sparse stations has low spatial and temporal resolution, which is not able to represent the actual exposure of individuals. A tool that can accurately monitor personal exposure provides valuable data for epidemiologists to understand the relationship between air pollution and certain diseases. It also allows individuals to be aware of any ambient air quality issues and prevent air pollution exposure. To build such a tool, sensors with features of fast response, small size, long lifetime, high sensitivity, high selectivity, and multi-analyte sensing are of great importance.
In order to meet these requirements, three generations of novel colorimetric sensors have been developed. The first generation is mosaic colorimetric sensors based on tiny sensor blocks and by detecting absorbance change after each air sample injection, the target analyte concentration can be measured. The second generation is a gradient-based colorimetric sensor. Lateral transport of analytes across the colorimetric sensor surface creates a color gradient that shifts along the transport direction over time, and the sensor tracks the gradient shift and converts it into analyte concentration in real-time. The third generation is gradient-based colorimetric arrays fabricated by inkjet-printing method that integrates multiple sensors on a miniaturized sensor chip. Unlike traditional colorimetric sensors, such as detection tubes and optoelectronic nose, that are typically for one-time use, the presented three generations of colorimetric sensors aim to continuously monitor multiple air pollutants and the sensor lifetime and fabrication methods have been improved over each generation. Ozone, nitrogen dioxide, formaldehyde and carbon monoxide are chosen as analytes of interest. The performance of sensors has been validated in the lab and field tests, proving the capability of the sensors to be used for personal exposure monitoring.<br>Dissertation/Thesis<br>Doctoral Dissertation Chemistry 2019
28
Lin, Yu-Lung, and 林裕榮. "Application of gold nanoparticles colorimetric method for the detection of mercury ion in aqueous solution." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/25763130916226331235.
Full textAbstract:
碩士<br>高雄醫學大學<br>醫藥暨應用化學研究所<br>101<br>Mercury (II) ion (Hg2+) not only has high toxicity but also causes serious pollution problems. Meanwhile, it also harms people’s health. Therefore, to develop an easy and quick way to detect Hg2+ has become important. This research aims to The main principle of this study is to use the gold nanoparticles’ surface plasmon resonance (SPR) effect. During the detection, the aggregation of AuNPs after the addition of aggregation agents is affected by the presence of Hg2+ and the degree of aggregation shows an inverse proportional to the concentration of Hg2+. Therefore, by observing the absorption maxima of SPR spectra, the concentration of Hg2+ can be predicted. By adjusting the concentration of acetate buffer, pH, anion concentration, the molar ratio between AuNPs and the aggregation agent, the sensing system is optimized. Since the high stability constant between L-cysteine and Hg2+, the proposed method shows high selectivity against Hg2+. As a result, we have developed a simple and fast approach for the detection of Hg2+ by using L-cysteine and unmodified gold nanoparticles. Under the optimal condition, the limit of the detection can be reached down to 100 nM.
29
Zhong, Rui-Gong，, and 鍾瑞恭. "Using the Rapid Chloride Migration to Determine the Difference between Colorimetric Method and Chloride Profile." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/3qyhvu.
Full textAbstract:
碩士<br>國立臺灣海洋大學<br>材料工程研究所<br>107<br>According to the mechanism of ion transport, it can be divided into natural diffusion test and electrical migration test generally. In order to improve efficiency, many researchers adopt the electrical migration test, such as Rapid Chloride Penetration Test (RCPT) and Rapid Chloride Migration Test (RCM). Because Rapid Chloride Penetration Test (RCPT) is controversial, we took Rapid Chloride Migration Test (RCM) to do the research. Rapid Chloride Migration Test (RCM) used Colorimetric method to calculation non-steady state migration coefficient. This test may measure inaccuracy, due to Colorimetric method measurement of chloride depth is more subjective . Therefore, this study was further confirmed using chloride profile.
This research uses three series of concrete, Portland cement concrete、silica fume concrete and fly ash concrete, to compare the difference between Colorimetric method and Chloride Profile. The specimens were used four water binder ratios 0.35、0.45、0.55、0.65, used Rapid Chloride Migration Test (RCM) when the curing age were 28, 91 days. After the RCM, to measure the chloride depth by colorimetric method and chloride profile and analyzed the RCM test results for difference between the two kinds of non-steady state Migration coefficient.
In the Colorimetric method, the result shows that was easy to produce fuzzy region by using a wet cutter. And so this study suggests that the specimens split by using compression machine. The results of the color change of silver nitrate showed that the color change will gradually change from high concentration to low concentration area with time. The reaction completion time is at least 2 minutes. The surface chloride ( ) is content to 2N, color change boundary ( ) is content to 0.07N by the Colorimetric method accordance with NT Build 492. However, the results of chloride profile show that experiment values are not conform by NT Build 492.
Relationship between compressive strength and two kinds of non-steady state migration coefficient, only Portland cement concrete can be evaluation two kinds of non-steady state migration coefficient by using compressive strength. According to the relationship between the initial charge or the average charge and two kinds of non-steady state migration coefficient, it shows that the two kinds of non-steady state migration coefficient can be evaluated by using the initial charge or the average charge. The relationship between the non-steady state migration coefficient calculated by Colorimetric method and the non-steady state migration coefficient calculated by chloride profile is good.
Keywords: chloride, Rapid Chloride Migration Test, Colorimetric, chloride profile.
30
Su, Sheng-Yuan, and 蘇聖淵. "Development of rapid colorimetric assay and real-time duplex LAMP method to detect viral nucleic acid." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/48596477047745340466.
Full textAbstract:
碩士<br>國立臺灣大學<br>醫學檢驗暨生物技術學研究所<br>100<br>Loop-mediated isothermal amplification (LAMP) was established by Notomi et al. (2000). It uses 4-6 specific primers to recognize the target gene sequence and rapidly amplify under isothermal condition. Using this technique, we established a rapid colorimetric assay and a real-time duplex LAMP (dLAMP) method for viral nucleic acid detection. We anticipated that these two assays could be applied in blood screening, clinical diagnosis, and epidemiological investigation in the future.
In the rapid colorimetric assay, we first optimized and validated the HCMV-LAMP reaction, the viral detection limit was about 30 copies per reaction. Furthermore, we mixed colloidal gold with LAMP products. Gold nanoparticles (AuNPs) became accumulated and solution color changed from red to blue quickly in HCMV-LAMP negative situation. But in positive situation, the solution color kept in red more longer. This phenomenon might be based on decreasing the ionic strength along with increasing DNA numbers of the solution after the HCMV-LAMP reaction. For the dLAMP method, HBV and HCV were detected simultaneously. The viral detection limits were 50 copies for HBV and 60 copies for HCV. In viral identification, we first collected clinical samples containing HBV or HCV strains of different genotypes or subtypes, respectively. By post-dLAMP melting curve analysis, HBV and HCV had different and non-overlapped Tm confidence intervals as 85.49±1.34°C and 88.90±0.81°C, respectively. We also tested the possibility of clinical application of the dLAMP and Tm analysis in detection and differentiation of HBV and HCV. The positive predictive value (PPV) of dLAMP method was 88 %. The accuracy of Tm differentiation of HBV and HCV was 88.64 %, that of HBV was 83.72 %, HCV 93.33 %.
In conclusion, the specificity and sensitivity of colorimetric assay were similar to those of turbidimetry. Reading colors by naked-eye was simple and easy. This end-point assay is suitable for rapid qualitative analysis. However, the duplex LAMP detected the viral nucleic acid in real-time manner and differentiated HBV and HCV conveniently by melting temperature analysis. But the efficiency and accuracy rate were not satisfactory, and further improvement is required.
31
Chiu, Yu-An, and 邱鈺安. "Research of substrate specificity and a quick colorimetric activity assay method of UDP-glycosyltransferase from Bacillus cereus." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/22122637940286054559.
Full textAbstract:
碩士<br>國立交通大學<br>應用化學系分子科學碩博士班<br>99<br>Glycosyltransferases have many important biological functions in all species and in the use of disease treatment. Thus we need a real time and high-throughput method to analyze glycosyltransferase activity. In this research, we focus on the UDP-glycosyltransferase from Bacillus cereus (BcGT-1) catalytic reaction. BcGT-1 was successfully over-expressed in E. coli BL21 (DE3) and purified by DEAE column. In this research, we use a quick colorimetric activity assay for glycosyltransferase BcGT-1. The assay principle is based on the glycosylation activity of BcGT-1 on 4-nitrophenol. It provides a timesaving, simple and high-throughput for analyzing glycosyltransferase activity.
First, the nitrophenolic compounds with different nucleophilicity were used to be the glucose acceptors in BcGT-1 glycosylation reaction. The nucleophilicity of nitrophenolic compounds was observed to play an important role in enzymatic reaction. The activity of BcGT-1 was decreased when nucleophilicity of acceptor was reduced.
In addition, we also investigate the potential of BcGT-1 to be used in synthesis. Using the purified BcGT-1 to catalyze the glycosylation with different donors shows that this enzyme has high specificity to UDP-glucose. However, this enzyme can convert phenolic, thiolphenolic and aromatic amine to their respective glucosides successfully. It means that BcGT-1, has high potential to be used to synthesize novel glycosides like O-glucoside、S-glucoside and N-glucoside.
32
Lee, Cheng-Ho, and 李承和. "High Precision Colorimetric Method for the Determination of Dissolved Oxygen in Seawater and Studies of Possible Interfering Factors." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/03230894811690077672.
Full textAbstract:
碩士<br>國立臺灣大學<br>海洋研究所<br>101<br>This study investigates effects of temperature, iodide concentration, oxidants and suspended solid on the colorimetric determination of oxygen in natural waters. Since the measurement involves the mixture of two iodine species (i.e. I2 and I3-), the equilibrium between them becomes a crucial factor to the precision of the method. A high concentration of iodide in the pickling reagent was found essential to ensure a stable [I_3^- ]/[I_2 ] ratio. Besides, it was also found that elevated temperature can cause a lower signal of molecular iodine, but increase the absorbance of triiodide ion. An over-all increment of 0.4% per 1 ℃ has been observed for a freshwater sample having oxygen concentration of ca. 250 μM. Therefore, temperature deviation can not only change the equilibrium constant but also alter the spectra of both iodine species. To solve this problem, the spectrophotometer has been modified using a thermostat unit which ensures the temperature difference between samples be kept within 0.5 ℃. Iodate, hydrogen peroxide, nitrite which are known to exist in natural environment all interfere the oxygen measurement. A quick reverse pickling procedure can be used to identify the iodate interference. Addition of sodium azide is always suggested to remove overestimate from nitrite. Since the sampling for oxygen usually excludes filtration therefore suspended solid in a sample can be another source of error. Re-measurement of the absorbance of the same sample after adding sodium thiosulfate reagent to remove the iodine color is considered the most effective way to correct for the interference from turbid water.
33
Kaur, Daljit. "Development of a cheap and rapid method to determine calcium in milk fractions in an industrial environment." 2007. http://hdl.handle.net/10292/742.
Full textAbstract:
Milk contains high concentrations of calcium. It occurs in two forms, a free ionic form, and calcium associated with milk proteins (caseins). The latter association is called colloidal calcium phosphate. New Zealand Dairy Foods of Takanini is marketing a range of commercial milks in supermarkets. The company uses ultra filtration to concentrate milk proteins and calcium in different milk products. During ultra filtration, the fraction that is retained by the membrane is rich in calcium bound to proteins and the portion that passes through the membrane is richer in the free ionic form. The company wanted to develop a quick and an economical method that can be applied in industrial settings to determine calcium in both these fractions and in other milk products. This research aimed to develop a quick, wet chemistry method to measure calcium in milk fractions and to trial it in an industrial environment. Two methods, the so-called EDTA method and the atomic absorption spectrophotometric method (AA) were trialled as potential reference methods against which to compare results obtained by the method to be developed. The AA method was chosen due to its ease, accuracy and precision. (This could not be selected as the industrial method for a number of reasons.) A colorimetric method was favoured over other contenders. Two colorimetric dyes, Arsenazo I and o-cresolphthalein-complexone (CPC) were chosen to work with. Arsenazo I forms a purple complex with calcium in a suitable buffer at a range of pHs. o-Cresolphthalein-complexone also forms purple-coloured complexes at alkaline pHs. During method development with Arsenazo I, different buffers were trialled and a NaOH/ KCl buffer was selected for further development at pH 12. The method worked well during the development phase but with some inconsistent results at times. o-Cresolphthalein-complexone formed clear purple complexes with Clark and Lubs and 2-amino-2-methylpropanol (AMP) buffers. The key advantage of the CPC dye with AMP buffer was that when 8-hydroxyquinoline was included in the reaction mixture, it successfully masked coloured complex formation due to CPC with magnesium, which is present in milk at about 1/3 the calcium concentration. This effect did not work with Arsenazo I. However, the results obtained with the CPC method were lower than claimed values of most milks trialled during development. Both methods were compared for their precision and it was found that CPC method has better precision and was chosen for further development. To improve the accuracy and precision, various denaturing reagents were used to (hypothetically) release calcium from the caseins. Trichloroacetic acid at 25 % was more effective than the several other denaturing treatments tested. The finalised CPC method, using trichloroacetic acid, AMP and 8-hydroxyquinoline, was then used to monitor calcium concentration over four months in three milk products, skim, Xtra (retentate) and permeate. For all milks, the CPC values were lower than the AA reference values, and the values reported by a commercial analytical laboratory. The reasons for this are discussed, as are other changes in calcium concentration in the three milks throughout the trial. The correlation between the CPC and AA values was poor for Xtra, better for skim, and best for permeate. A chemical model to explain this is discussed. The method developed is cheap and quick, and sample and reagent preparation is simple. The method could be applied in an industrial environment, but a proportionality factor would have to be applied to account for the difference in mean values between the CPC and AA methods.
34
Wu, Cheng-Chieh, and 吳承杰. "A WEIGHTED MASKING MODEL BASED ON THE MODIFIED METHOD OF UNDER COLOR REMOVAL FOR ACCURATE COLORIMETRIC CHARACTERIZATION OF LCDS." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/12039913472122815774.
Full textAbstract:
碩士<br>大同大學<br>通訊工程研究所<br>96<br>Flat-panel displays have become increasingly popular because of its low power consumption and portability. In a color management system (CMS), accurate colorimetric characterization of a display device plays an important role in achieving device-independent color reproduction. In the case of a CRT display, colorimetric characterization based on a gain-offset-gamma (GOG) model is accurate enough for this purpose. However, that is not effective to characterize the colorimetry of liquid crystal displays (LCDs) since there are many difficulties, such as channel interaction and non-constancy of channel chromaticity due to the structural difference.
In this article, three weighted masking models based on different under color removal methods are proposed for colorimetric characterization of LCD. They are taken channel interaction and non-constancy of channel chromaticity into account for LCDs. In these models, the masking part approaches the phenomenon of channel interaction. The nonlinear mathematical function of GOG model is utilized as electro-optical transfer function (EOTF). Then the normalized DAC values are converted to the device-independent XYZ color space through the linear transform matrix. In order to have a precise prediction, the final stage is to find the optimal weights by using the relationship between three color components.
The performance comparison of conventional and proposed model is evaluated via CIEDE2000 color-difference formula. Experimental results show that the weighted masking model based on the method of under color removal is more effective in the colorimetry of LCDs.
35
Lee, Yi-Hsin, and 李奕欣. "Implementation of a fast indophenol blue colorimetric method for the determination of dissolved total ammonia using manganese (II) as a catalyst." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/ra6yqm.
Full textAbstract:
碩士<br>國立臺灣大學<br>海洋研究所<br>106<br>The indophenol blue method for the determination of dissolved ammonia has been reassessed in several analytical respects including pH control, reaction kinetics, choice of reagents and reagent stability. It was found that an optimal reaction rate (t99%<3 min at room temperature) can be achieved using phenol as the coupling agent, hypochlorite as the oxidant and manganese (II) as the catalyst. The key conditions are that the formation of the intermediate product-chloramine needs to form at pH 7-8, which further reacts with phenol at pH 8-8.5 and the final formation of the indophenol blue should be carried out at pH 10.5. The reagent blank of the proposed method is more stable than that of using dichloroisocyanurate and nitroprusside reagents. Even though the final molar extinction coefficient (640nm=4500 M-1cm-1) may be comparatively lower than that of traditional protocols, the present method takes advantages of being much faster, more consistent and all reagents can be stable for several months. The detection limit using a stop-flow automated device was 0.5 uM using 1 cm cell measured at 640 nm, and the precision was about 1% at 10 uM level with a linear range of up to 100 uM. The analysis throughput was 15 samples per hour. The method is suitable for the examination of high-ammonia-containing urban sewage, industrial and agricultural outflows as well as rain water and aquaculture pond water.
36
Li, Wong-Ta, and 李旺達. "The Influence of Chloride Concentration in Color Change Region with Colorimetric Method on the Non-steady-state Chloride Diffusibility of Concrete." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/58904069461795974065.
Full textAbstract:
碩士<br>國立臺灣海洋大學<br>材料工程研究所<br>94<br>The purpose of this thesis is using Accelerated Chloride Migration Test ( ACMT ) and the colorimetric method to determinate the non-steady -state chloride migration coefficient. To make sure the chloride ion must not pass through the concrete specimen, and to discuss the chloride migration coefficient under the non-steady-state situation, this thesis using ACMT with concrete specimen of 5 cm thickness and 24 hours test duration. After ACMT, the analysis of experiment is divided into two parts. One is to use colorimetric method to determinate the chloride penetrate depth and migration coefficient, the other is to use acid soluble experiment to find the relationship of chloride profile.
A simple colorimetric method of measuring the depth of chloride penetration into concrete is by spraying 0.1N AgNO3. However, there are still some questions. for example, colorimetric method is limited to the original Portland concrete , the chloride content at which the color changes is assume as 0.07N of OPC concrete. This thesis also confer the relationship between the chloride concentration and the chloride penetrate depth, using the regression to determine the chloride content is 0.02% by weight of concrete at the color change region.
The influence of the difference to the Cd/Co in the non-steady-state chloride migration coefficient is not sufficient. To discusses whether the chloride concentration while color change is 0.07 N, this experiment is conducted to proof that the chloride concentration at color change is not only the aptotic value , but also decrease while w/c increase .
37
Chen, Li-fei, and 陳麗妃. "Study of Colorimetry Using Vat Dyes with Padding Method on Cotton." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/28136330435321989898.
Full textAbstract:
碩士<br>逢甲大學<br>紡織工程所<br>96<br>Cotton and cellulose fibers are very important textile. They are used in whole world and their consumption is increasing. Vat dye is one of the most popular dye classes used for coloration of cotton in today’s dyeing industry because vat dyes yield coloured fiber of excellent all-round fastness, particularly to light, washing and chlorine bleaching. Vat dyes play an important role in blue jeans. Although only 10 g of indigo is necessary for dyeing one pair of trousers, the vast annual sales of 109 blue jeans in the whole world.
By the trend of time, the quality of dyeing is requested. Color reproduction is very necessary in dyeing processes. If we understand the properties of vat dyes, thousands of textiles will be made the same colorimetry. The potential between the vat dyes proves decisive, so choosing right dye to mix is an important part. To know the properties of vat dyes and find the best condition in order to control the usage amount of reducer and reduce much waste water.
This experiment treats about the colorimetry and characterization on three different brands of vat dyes. Redox titrations at various pH values or temperature and titrations after milling were carried out to determine the leuco potential of vat dyes. To choose the stable dyes, and observe the change of colorimetry by padding on cotton. Observe and discuss the cotton color change after different oxidation processes and find the method that how to control the colour of dyeing.
The experimental result shows the best dyeing condition of three brands vat dyes is between 10 and 30 ℃, and the leveling property is better after milling. Vat dyes yield coloured fibres will get stable coloration through enough oxidizing process. The washing fastness of all dyeings was rated at 4-5.The rub fastness is higher after milling and at high temperature.
38
Cheng, Chia-Lun, and 鄭家侖. "comparison of the two modified colorimetric methods on the feasibility of measuring oxygen in acidic mine water." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/44248655324408219220.
Full textAbstract:
碩士<br>國立臺灣大學<br>海洋研究所<br>95<br>Oxygen in acidic mine water is difficult to measure by colorimetry because such water contains high amount of dissolved iron which interferes. Both ferric and ferrous ions produce excess molecular iodine and triiodide thus leading to overestimated results. To solve this problem, a modified colorimetric method is proposed in which the sample is added with permanganate prior to the pickling procedure and all ferrous ions are converted to ferric ions. The sample was further treated with K2C2O4 and KF to remove the interference of permanganate and ferric ions. After acidification iodine and triiodide are formed and the color of the final solution was measured at 456 nm. Another simplified procedure was also compared by neglecting the addition of KF. Excess iodine generated due to ferric ions is compensated by a parallel sample that is pickled with the same reagent but in reverse order. The methods have been applied to measure the oxygen in the run-off water from an abandoned mining area, and the results are in agreement with data obtained by modified titration method and a well-calibrated oxygen sensor.
39
Zunnoon, Khan Sara. "Towards Development of an Immunoassay Utilizing Circularly Permutated Proteins to Detect Environmental Contaminants." Thesis, 2013. http://hdl.handle.net/10214/7434.
Full textAbstract:
A fusion protein composed of antibody fragments and β-lactamase was earlier created by Kojima et al. (2011), with antigen specificities against a bone disease marker and a pesticide. The enzyme was circularly permutated and fused to the variable heavy and light chain antibody fragments, thereby ensuring inactivity until binding of the target antigen triggered enzyme
activation. Upon activation, the β-lactamase produced a colorimetric signal, which indicated antigen presence. In this work, a similar strategy was used to create two novel fusion proteins composed of circularly permuted β-lactamase and superfolder green fluorescent protein with anti-benzo[a]pyrene variable antibody fragments. The fusion proteins were designed and expressed in E. coli for the development of a single-step visual immunoassay. It was hypothesized that the cp reporter proteins would be activated once the binding of B[a]P to the variable antibody fragments occurred, and this interaction was expected to produce a detectable colorimetric or fluorescent signal. Although positive results were obtained in one instance, substantial supportive evidence in favour of the hypothesis could not be obtained.<br>SENTINEL Bioactive Paper Network, Natural Sciences and Engineering Research Council of Canada (NSERC), Canada Research Chairs Program.