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Conjugação de processos fisico-quimicos ( UV;H2O2; UV/H2O2; reagente de fenton; foto-fenton) e biologico (lodos ativados) para tratamento de aguas residuarias contendo formol / Combined physical-chemistry (UV; H2O2; UV/H2O2; reagent of fenton; photo-Fenton) and biological (activated sludge) process for treatment of contaminated wastewater by formaldehydeFarah, Carolina Rittes Turato 28 February 2007 (has links)
Orientador: Jose Roberto Guimaraes, Pedro Sergio Fadini / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil / Made available in DSpace on 2018-08-09T14:26:18Z (GMT). No. of bitstreams: 1
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Previous issue date: 2007 / Resumo: Nesse trabalho foram realizados ensaios de tratabilidade de soluções e efluentes contendo formol conjugando-se processos físico-químicos com biológicos. Dentre os vários processos, o UV/H2O2 foi o que apresentou a melhor eficácia no tratamento do efluente do Laboratório de Anatomia/IB-UNICAMP. A redução dos teores de CH2O, COD, DQO e DBO, foram 91, 48, 46 e 53 % para o UV/H2O2 e, 94, 38, 38 e 43 % para o Foto-Fenton, respectivamente, ao final de 420 minutos de ensaio. Para uma solução de formol com concentração inicial de 12.000 mg L-1, as reduções de COD foram de 65 e 61 %, para Foto-Fenton e UV/H2O2, respectivamente, ao final de 390 minutos de ensaio. Para soluções com 400 mg L-1 em formol as redu?es em COD foram 65 e 98 % nos processos Foto-Fenton e UV/H2O2, respectivamente, em ensaios com 120 minutos de duração. O sistema Lodo Ativado por Batelada convencional (?c 7 dias) apresentou reduções nos valores de COD, DQO e DBO de 88, 83 e 96 % e 88, 86 e 98 % para sistemas com aeração prolongada (?c 20 dias), alimentados com efluente tratado por POA / Abstract: In this work assays of treatment of solutions had been carried through and effluent I contend formaldehyde conjugating processes physicist-chemistries with biological. Amongst the some processes, the UV/H2O2 was what it presented the best efficiency in the treatment of the effluent one of the "Laboratorio de Anatomia/IB-UNICAMP. The reduction of the values of the CH2O, COD, DQO and DBO, had been 91, 48, 46 and 53 % for the UV/H2O2 and, 94, 38, 38 and 43 % for Photo- Fenton, in the 420 minutes of assay, respectively. Solution of formaldehyde with initial concentration of 12.000 mg L-1, the TOC reductions had been of 65 and 61 %, for Photo-Fenton and UV/H2O2, respectively, for 390 minutes of assay. For solutions with 400 mg L-1 in formaldehyde the reductions in TOC had been 65 and 98 % in processes Photo-Fenton and UV/H2O2, respectively, for 120 minutes of assay. Systems Activated Sludge had presented reductions in the values of TOC, COD and BOD of 88, 83 and 96 % for conventional systems (?c 7 days) and 88, 86 and 98 % for systems with drawn out aeration (?c 20 days), using effluent treated by POA / Doutorado / Saneamento e Ambiente / Doutor em Engenharia Civil
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Estudo comparativo das emissões de aldeídos originados pelo veículo à diesel com o uso do óleo diesel comercial, biodiesel e suas misturas / Comparative study of aldehyde emissions generated by Diesel vehicles using of commercial diesel fuel, biodiesel and their mixturesEdegar Yoshio Hirai 29 October 2009 (has links)
Em razão do óleo diesel combustível automotivo, conter 2% de biodiesel e por não existir ainda regulamentação de emissões para os aldeídos dos veículos do ciclo Diesel, o presente trabalho teve como objetivo, avaliar as emissões de aldeídos dessa categoria de veículos, utilizando-se o óleo diesel com 2% de biodiesel (B2) e 100% de biodiesel de soja (B100) como combustível. Procurou-se também, avaliar as emissões de aldeídos de um veículo leve do ciclo Otto com e sem o conversor catalítico, a fim de comparar suas emissões com o veiculo do ciclo diesel, uma vez que o programa de controle da poluição do ar por veículos automotores estabeleceu limite de emissão de aldeídos totais, (formaldeído + acetaldeído) para os veículos leves novos do ciclo Otto, movidos a gasolina, etanol hidratado e suas misturas. Os ensaios foram realizados no laboratório de emissão veicular da CETESB em dinamômetro de chassi, seguindo um ciclo de condução urbano padronizado. Os aldeídos foram analisados por cromatografia líquida de alto desempenho. Os ensaios foram realizados com o veículo de marca Citröen modelo JUMPER 2.8 L ano/modelo 2006 para o ciclo Diesel e com o veículo de marca VW modelo FOX 1.6 Flex ano/modelo 2005 com e sem o conversor catalítico para o ciclo Otto. Nos ensaios realizados com o veículo JUMPER, além de medir as emissões de formaldeído e acetaldeído, mediu-se também as emissões de acroleína, propionaldeído, butiraldeído e benzaldeído. Observou-se na emissão, a presença de outras carbonilas e cetonas, tais como: crotonaldeído, metacroleína, 2-butanona, valeraldeído e p-tolualdeído, porém, essas carbonilas não foram quantificadas nesse estudo, em razão de não dispormos de padrões individuais certificados. Os ensaios demonstraram que com o uso do B2, as emissões de formaldeído variaram de 7,6 e 14,9 mg/km; o acetaldeído de 4,5 e 8,9 mg/km; a acroleína de 2,7 e 5,8 mg/km; o pr butiraldeído 0,4 e 0,7 mg/km e o benzaldeído de 0,2 e 0,3 mg/km, enquanto que com o uso do B100 as emissões de formaldeído variaram de 18,8 e 21,1 mg/km; o acetaldeído de 7,5 e 8,3 mg/km; a acroleína de 5,2 e 6,2 mg/km; o propionaldeído de 0,5 e 0,6 mg/km; o butiraldeído de 0,4 mg/km e o benzaldeído de 0,4 mg/km. Verificou-se que com o uso do B2, a emissão média foi de 48% para o formaldeído e 29% para o acetaldeído e representava 77% dos aldeídos totais (17,9 mg/km). Com o uso do B100, a emissão média foi de 57% para o formaldeído e 23% para o acetaldeído e representava 80% dos aldeídos totais (27,9 mg/km). Pode-se, observar nesse trabalho que a emissão média encontrada de 17,9 e 27,9 mg/km de aldeídos totais (formaldeído e acetaldeído) do veículo Diesel em relação à emissão do veículo Otto, não é desprezível, uma vez que o limite de emissão de aldeídos totais para os veículos leves fabricados a partir de 1997 era de 30,0 mg/km e passou a 20,0 mg/km para os veículos fabricados a partir de 2009, portanto, conclui-se que a realização de mais ensaios, inclusive em dinamômetro de motores e com outras categorias de veículos, contribuirá para detalhar o perfil das emissões de aldeídos da frota dos veículos a Diesel e biodiesel, além de determinar fatores de deterioração destes veículos, bem como ajudar no inventário de emissões destes poluentes. / Since of the automotive diesel fuel contains 2% biodiesel and there exists no regulation of emissions of aldehydes of Diesel cycle vehicles, this paper aims to evaluate the emissions of aldehydes of such a category of vehicles, using diesel oil with 2% biodiesel (B2) and 100% soybean biodiesel (B100) as fuel. It also aims to evaluate the emissions of aldehydes from a light Otto cycle vehicle with and without the catalytic converter in order to compare their emissions with the Diesel cycle vehicle, as the control program for air pollution by motor vehicles has set a limit of emissions of total aldehydes (formaldehyde + acetaldehyde) for new light Otto cycle vehicles, powered by gasoline, hydrated ethanol and its mixtures thereof. The tests were conducted in the vehicle emission laboratory of environmental sanitation agency (CETESB) on a chassis dynamometer, following a standard urban driving cycle. The aldehydes were analyzed by high performance liquid chromatography. The tests were conducted in a Citröen JUMPER 2.8 L vehicle model year/model 2006 for the Diesel cycle, a VW FOX 1.6 Flex vehicle model year/model 2005 with and without the catalytic converter for the Otto cycle. In the tests with the Jumper vehicle, the emissions of both formaldehyde and acetaldehyde, and acrolein, propionaldehyde, butyraldehyde and benzaldehyde were measured. It was possible to observe, the presence of carbonyl and other ketones, such as crotonaldehyde, methacrolein, 2-butanone, valeraldehyde and p-tolualdehyde. However these carbonyls were not quantified in this study, as there are no certified individual standards. The tests showed that by using B2, the emissions of formaldehyde ranged from 7.6 to 14.9 mg/km, acetaldehyde from 4.5 to 8.9 mg/km, acrolein from 2.7 to 5.8 mg/km, propionaldehyde from 0.4 to 0.6 mg/km, butyraldehyde from 0.4 to 0.7 mg/km, and benzaldehyde from 0.2 to 0.3 mg/km, while using B100 emissions of formaldehyde ranged from 18.8 to 21.1 mg/km, acetaldehyde from 7.5 to 8.3 mg/km, acrolein from 5.2 to 6.2 mg/km, propionaldehyde from 0.5 to 0.6 mg/km, butyraldehyde of 0.4 mg/km, and benzaldehyde of 0.4 mg/km. It was found that by using B2, the average emissions were 48% for formaldehyde and 29% for acetaldehyde, representing 77% of total aldehydes (17.9 mg/km). Using B100, the average emissions were 57% for formaldehyde and 23% for acetaldehyde, representing 80% of total aldehydes (27.9 mg/km). It was possible to observe in this study that the average emissions of 17.9 and 27.9 mg/km of total aldehydes (formaldehyde and acetaldehyde) of Diesel vehicle emissions in the Otto vehicle, are significant, since the emission limit of total aldehydes for light vehicles manufactured from 1997 was 30.0 mg/km and passed to 20.0 mg/km for vehicles manufactured from 2009. Therefore, it is possible to conclude that performing more tests, including engine dynamometer and other types of vehicles, will detail the profile of the aldehyde emissions from the fleet of vehicles powered by diesel and biodiesel, as well as determine factors for the deterioration of these vehicles and assist in the inventory of emissions of these pollutants.
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Efeitos do Laser de Baixa Intensidade em pulpotomias de dentes decíduos humanos / Effects of low-level laser therapy on pulpotomy of human primary teethNádia Carolina Teixeira Marques 01 April 2013 (has links)
O objetivo deste estudo foi avaliar por meio de análises clínicas, radiográficas e histológicas o efeito do Laser de Baixa Intensidade na resposta pulpar de dentes decíduos humanos após pulpotomia. Vinte molares decíduos inferiores de 16 crianças com idade entre 6 e 9 anos foram criteriosamente selecionados. Os dentes foram randomizadamente divididos nos grupos Formocresol de Buckley diluído a 1/5 (Grupo I - FC), Hidróxido de Cálcio (Grupo II - HC), Laser de Baixa Intensidade + Óxido de Zinco e Eugenol (Grupo III - LBI+OZE) e Laser de Baixa Intensidade + Hidróxido de Cálcio (Grupo IV - LBI+HC), e tratados pela técnica convencional de pulpotomia em uma única sessão. As avaliações clínicas e radiográficas foram realizadas nos períodos de 3 e 6 meses do pós-operatório. Os dentes que se apresentavam em período normal de esfoliação foram extraídos, processados para análise histológica e avaliados por sistema de escores. Os resultados clínicos e radiográficos não mostraram diferença estatisticamente significativa nos grupos estudados (p>0,05). A análise estatística da avaliação histológica revelou diferença estatisticamente significativa para inflamação pulpar entre os Grupos I (FC) e IV (LBI+HC), sendo que o Grupo IV(LBI+HC) apresentou menor grau de inflamação pulpar. Em relação à fibras colágenas, formação de barreira de tecido mineralizado e camada odontoblástica houve diferença entre os Grupos I (FC) e II (HC), e entre os Grupos II (HC) e III (LBI+OZE), sendo que o Grupo II (HC) apresentou fibras colágenas densas, barreira de tecido mineralizado e camada odontoblástica. Os Grupos I (FC) e III (LBI+OZE), e os Grupos I (FC) e IV (LBI+HC), apresentaram diferença estatisticamente significativa para reabsorção interna. O Grupo I (FC) apresentou maior índice de reabsorção interna. Não houve diferença estatisticamente significativa entre os grupos para vitalidade pulpar, quantidade de vasos, calcificação pulpar e tecido de granulação. Com base nos resultados obtidos foi possível constatar que o Laser de Baixa Intensidade com Hidróxido de Cálcio mostrou efeitos clínicos e radiográficos mais satisfatórios, e melhores resultados histológicos em comparação aos demais grupos estudados. Desta forma, sugere-se que o Laser de Baixa Intensidade com hidróxido de Cálcio pode ser considerado uma técnica alternativa para pulpotomia de dentes decíduos humanos. / The aim of this study was to evaluate through clinical, radiographic and histological analyses the effect of Low-Level Laser therapy (LLLT) on pulpal response of human primary teeth after pulpotomy. Twenty mandibular primary molars of 16 children aged between 6 and 9 years were criteriously selected. The teeth were randomly divided into the following groups: Buckleys Formocresol (diluted 1:5) group I (FC), Calcium Hydroxide - group II (CH), Low-Level Laser therapy + Zinc Oxide and Eugenol - group III (LLLT+ZOE), and Low-Level Laser therapy + Calcium Hydroxide - group IV (LLLT+CH), and treated by the conventional pulpotomy technique at a single appointment. The clinical and radiographic evaluations were performed at 3 and 6 post-operative months. The teeth underwent normal exfoliation period were extracted and processed for histological analysis and assessed through a score system. The clinical and radiographic results did not show statistically significant difference among groups (p>0.05). The statistical analysis of the histological assessment revealed statistically significant difference for pulpal inflammation between groups I (FC) and IV (LLLT+CH), with the least degree of pulpal inflammation for group IV (LLLT+CH). Concerning to the collagen fibers, hard tissue barrier and odontoblastic layer, there were differences between groups I (FC) and II (CH), and between groups II (CH) and III (LLLT+ZOE). Group II (CH) showed dense collagen fibers, hard tissue barrier and odontoblastic layer. Groups I (FC) and III (LLLT+ZOE), and groups I (FC) and IV (LLLT+CH), presented statistically significant difference for internal resorption. Group I (FC) displayed the greatest internal resorption rate. There was not statistically significant difference among groups for pulpal vitality, amount of vessels, pulpal calcification and connective tissue. Based on the results obtained, it was possible to know that Low-Level Laser therapy with Calcium Hydroxide exhibited clinical and radiographic effects more satisfactory, and the best histological effects compared with the other groups studied. Therefore, it is suggested that Low-Level Laser therapy with Calcium Hydroxide can be considered as an alternative technique for the pulpotomy of human primary teeth.
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The Development of a Fluorescence-based Reverse Flow Injection Analysis (rFIA) Method for Quantifying Ammonium at Nanomolar Concentrations in Oligotrophic SeawaterAbbott, William 05 November 2015 (has links)
The goal of this thesis was to adopt a reverse flow injection analysis (rFIA) technique to the fluorometric analysis of the reaction o-phthaldialdehyde (OPA) with ammonium, allowing accurate measurements of ammonium concentrations lower than the detection limit of the widely used indophenol blue (IPB) colorimetric method while accounting for the background fluorescence of seawater. Ammonium is considered an essential nutrient for primary productivity, especially in the nutrient depleted surface ocean where as the most reduced form of dissolved inorganic nitrogen, it is readily assimilated via metabolic pathways. Challenges in the quantification of ammonium require more sensitive analytical techniques for a greater understanding of the biogeochemical cycling of ammonium in the oligotrophic ocean. On-line and automated flow analysis techniques are capable of mitigating some of the challenges. Fluorescent-based methods out-perform colorimetric methods in terms of detection limits and sensitivity. Presented here is the development of an rFIA technique paired with an OPA-sulfite chemistry. For this method, a sulfite-formaldehyde reagent is mixed with the sample stream and then injected with the OPA reagent before being heated. Fluorescence is measured before and at the peak of the OPA injection, differentiating the background fluorescence from the analyte signal. Experiments to optimize reaction parameters and characterize the effects of salinity and potentially interfering species were conducted. The newly developed method offers a reasonable throughput (18 samples per hour), low limit of detection (1.1 nM) ammonium analysis technique with automatic background fluorescence correction suitable for oligotrophic seawater as a preferable alternative to the low sensitivity and high limit of detection IPB colorimetric method.
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Microbiocapteurs conductimétriques utilisant des oxydoréductases : de la conception à l’application à l’environnement et l’agroalimentaire / Conductometric microbiosensors using oxidoreductases : from the design to environmental and food industry applicationsNguyen Boisse, Thanh Thuy 02 July 2013 (has links)
Les biocapteurs sont des moyens d'analyse en plein essor à la fois rapides, sélectifs et peu coûteux applicables à des domaines extrêmement variés (environnement, santé, agroalimentaire,…). Dans ce type d'outil, un élément sensible de nature biologique (anticorps, enzyme, microorganisme, ADN…) doté d'un pouvoir de reconnaissance pour un analyte ou un groupe d'analytes est associé à un transducteur pouvant être de type électrochimique, optique ou thermique. Dans ce travail, nous nous sommes intéressés au développement de trois biocapteurs utilisant des enzymes de la famille des oxydo-réductases (alcool oxydase, lactate oxydase et formaldéhyde déshydrogénase) pour la détection d'analytes d'intérêt dans le domaine de l'agroalimentaire ou de l'environnement (alcools, lactate et formaldéhyde). Les trois enzymes ont été immobilisées sur des microélectrodes interdigitées en or en vue d'une détection conductimétrique. Nous avons cherché à mieux comprendre le fonctionnement des biocapteurs et optimisé le procédé d'immobilisation des enzymes ainsi que différents paramètres de fabrication ou de mesure afin de maximiser les performances analytiques des outils développés (sélectivité, limite de détection, reproductibilité, stabilité). Nous avons également démontré les potentialités d'application des deux biocapteurs conductimétriques à base de lactate oxydase et de formaldéhyde déshydrogénase pour la détection du lactate dans les produits laitiers et du formaldéhyde dans les eaux / Biosensors are rapid, selective and inexpensive devices that combine a biological recognition element, the so-called bioreceptor (e.g. enzymes, antibodies, DNA or microorganisms) to a physical transducer (e.g. electrochemical, optical, thermal or piezoelectrical). They can be used to detect one specific analyte or one family of analytes for a wide range of applications (e.g. environment, food, health). In this work, we developed biosensors based on three oxidoreductases (alcohol oxidase, lactate oxidase and formaldehyde dehydrogenase) for primary alcohols, lactate and formaldehyde analysis. The three enzymes were immobilized on interdigitated gold microelectrodes in view of conductometric detection. We tried to achieve a better understanding of biosensors processing and optimized enzyme immobilization as well as several fabrication or operational parameters to maximize analytical performances (selectivity, detection limit, reproducibility and stability). We also demonstrated the applicability of both conductometric biosensors based on lactate oxidase and formaldehyde dehydrogenase for the detection of lactate in dairy products and formaldehyde in waters
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Rotation-vibration spectroscopic studies of formaldehyde and formic acidLohilahti, J. (Jarmo) 10 May 2006 (has links)
Abstract
The thesis consists of seven studies dealing with high resolution vibration-rotation spectra of planar asymmetric tops. Six studies deal with D212CO and D213CO species of the formaldehyde molecule and one study is from DCOOH specie of the formic acid molecule. The measurements were carried out at high accuracy and the rotational analyses of the recorded spectra were performed. The observed anharmonic and Coriolis resonances were taking into account in the analyses. The rotational constants of the present and literature studies were used in evaluation of the planarity defects of formaldehyde and formic acid molecules in the summary part of the thesis. Finally, a semi-experimental structure for formaldehyde was obtained by employing experimental and theoretical data.
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The recycling of resorcinol formaldehyde latex coated nylon 66Wroe, Sarah January 2013 (has links)
The Waste (England and Wales) Regulations encourage business to recycle their waste, as an alternative to landfill. This study has evaluated a number of processing techniques with respect to a difficult to recycle, technical textile, in order to develop recycling opportunities. Resorcinol formaldehyde latex (RFL) coated nylon 66 is a high performance fabric used as an interface to reinforce rubber products such as timing belts. The characteristics of the RFL coated woven fabric, assessed in comparison to equivalent uncoated fabrics, showed increased stiffness and decreased tear resistance. This was followed by the evaluation of three reduction processes:1) The Laroche Cadette shredder;2) The Hollander beater;3) The Intimus disintegrator. The fibre length, coating integrity and degradation properties were assessed for each of the reduction techniques. The longest fibres were produced by the Laroche Cadette shredder, this method proved most suitable for textile processing. The coating was unaffected and little degradation occurred. The Hollander beater produced mid-length fibres; however, fibres as short as 2mm could also be achieved. The material did not degrade, as water used within the process reduced heat build up, the coating remained adhered to the fibre. The Intimus Disintegrator produced the smallest fibre length and produced the greatest processing problem due to heat build up and degradation. Particles in addition to fibres were formed but were not crystalline in nature, and were difficult to process further. Processing using paper, textile, plastic and rubber technology were trialled with varying success. The recommended recycling route was found to be through reduction using the Hollander beater followed by incorporation of the waste as filler in rubber composites. RFL coated fibres gave additional strength to the rubber at high filler contents of 37.5% in comparison to uncoated waste filler also trialled. This was due to the surface chemistry of the RFL coated nylon fibre. The RFL coated nylon 66 filler also enabled the composites to exceed tear specifications required for hardwearing footwear. Fibres were effectively separated by length using forward flow and reverse flow hydrocyclones, separating 10mm and 3mm length fibres, which would prove useful for obtaining optimum particle size for reinforcement during the reduction process. Alternate processed trialled enabled the RFL fibres to be formed into a paper sheet using 50% cellulose pulp but textile processes proved unsuccessful. Moulded pieces formed though compression moulding were able to be produced from coated and uncoated fabric pieces, however many voids were present, limiting the usability.
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Thin films for indoor air monitoring : Measurements of Volatile Organic CompoundsCindemir, Umut January 2016 (has links)
Volatile organic compounds (VOCs) in the indoor air have adverse effects on the dwellers residing in a building or a vehicle. One of these effects is called sick building syndrome (SBS). SBS refers to situations in which the users of a building develop acute health effects and discomfort depending on the time they spend inside some buildings without having any specific illness. Furthermore, monitoring volatile organic compounds could lead to early diagnosis of specific illnesses through breath analysis. Among those VOCs formaldehyde, acetaldehyde can be listed. In this thesis, VOC detecting thin film sensors have been investigated. Such sensors have been manufactured using semiconducting metal oxides, ligand activated gold nanoparticles and Graphene/TiO2 mixtures. Advanced gas deposition unit, have been used to produce NiO thin films and Au nanoparticles. DC magnetron sputtering has been used to produce InSnO and VO2 thin film sensors. Graphene/TiO2 sensors have been manufactured using doctor-blading. While presenting the results, first, material characterization details are presented for each sensor, then, gas sensing results are presented. Morphologies, crystalline structures and chemical properties have been analyzed using scanning electron microscopy, X-ray diffraction and X-ray photo electron spectroscopy. Furthermore, more detailed analyses have been performed on NiO samples using extended X-ray absorption fine structure method and N2 adsorption measurements. Gas sensing measurements were focused on monitoring formaldehyde and acetaldehyde. However, responses ethanol and methane were measured in some cases to monitor selectivity. Graphene/TiO2 samples were used to monitor NO2 and NH3. For NiO thin film sensors and Au nano particles, fluctuation enhanced gas sensing is also presented in addition to conductometric measurements.
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Comparison on the thermal degradation kinetics and mechanism of hides before and after formaldehyde-tanningHu, Yadi, Luo, Lan, Liu, Jie, Wang, Fang, Zhu, Haolin, Tang, Keyong 28 June 2019 (has links)
Content:
The thermal degradation kinetics of hides before and after being tanned with formaldehyde were investigated using thermalgravimetric analysis (TGA) at four different heating rates of 5, 10, 20, 30 K/min.
Such model-free methods as Flynn-Wall-Ozawa and Friedman as well as model-fitting method of Criado were employed to determine the thermal degradation active energy and degradation mechanism. Based on the Flynn-Wall-Ozawa and Friedman methods, the average active energy (Ea) of formaldehyde-tanned leather was 223.1 kJ/mol and 230.7 kJ/mol respectively. Results from general master curves showed diffusion processes in the thermal degradation of formaldehyde-tanned leather. Neither the thermal degradation activation energy nor the degradation mechanism is affected by the formaldehyde tanning. Nevertheless, the results by thermalgravimetric analyzer coupled with Fourier transform infrared spectrometry (TG-FTIR) indicated difference in the relative amounts of evolved products. According to the 3D-FTIR analysis, the dominant components of evolved gas for both untanned and tanned hides are CO2, CH4, H2O, NH3 along with small amount of HNCO. However, after formaldehyde tanning, both the evolved NH3 by the decomposition of free –NH2 groups and peptide –NH– groups from different amino acids in collagen and CH4 by the cleavage of -CH3 and -CH2- increase.
Take-Away:
1. The theraml degradtion mechanism of hides before and after formaldehyde-tanning is eatablished in our paper.
2. The main degradation pathway of hides before and after formaldehyde-tanning is discussed with the help of TG-FTIR analysis.
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Stanovení stability přípravku TauroLock / Determination of TauroLock stabilityMatejčíková, Eva January 2018 (has links)
This diploma thesis deals with the study of the anticoagulant and antimicrobial agent TauroLockTM, which is manufactured by the german company TauroPharm GmbH. Based on the background research and taking into account the equipment of analytical laboratories of the Institute of Chemistry and Technology of Environmental Protection, optimal methods of analysis were proposed and a series of experiments were carried out which focused on the determination of the active substance and degradation products of taurolidine in TauroLockTM which was stored for a certain period of time in real conditions. The main task of this work was to determine the presence of taurolidine as the active substance and formaldehyde as the undesirable product of its decomposition.
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