Дисертації: "Filter products"

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Ma, Guojun. "Cr(VI)-containing electric furnace dust and filter cake characteristics, formation, leachability and stabilisation /." Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-10182006-163226.

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CORREA, LEONARDO GUILHERME CAETANO. "INFERENCE OF THE QUALITY OF DESTILLATION PRODUCTS USING ARTIFICIAL NEURAL NETS AND FILTER OF EXTENDED KALMAN." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2005. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=7588@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
Atualmente cresce o interesse científico e industrial na elaboração de métodos de controle não lineares. Porém, estes modelos costumam ter difícil implementação e um custo elevado até que se obtenha uma ferramenta de controle confiável. Desta forma, estudos na área de métodos de apoio à decisão procuram desenvolver aplicações inteligentes com custos reduzidos, capazes de executar controles industriais avançados com excelentes resultados, como no caso da indústria petroquímica. Na destilação de derivados de petróleo, por exemplo, é comum fazer uso de análises laboratoriais de amostras para identificar se uma substância está com suas características físico-químicas dentro das normas internacionais de produção. Além disso, o laudo pericial desta análise permite regular os instrumentos da planta de produção para que se consiga um controle mais acurado do processo e, conseqüentemente, um produto final com maior qualidade. Entretanto, apesar da análise laboratorial ter maior acurácia nos resultados que avaliam a qualidade do produto final, exige, às vezes, muitas horas de análise, o que retarda o ajuste dos equipamentos de produção, reduzindo a eficiência do processo e aumentando o tempo de produção de certos produtos, que precisam ter sua composição, posteriormente, corrigida com outros reagentes. Outra desvantagem está relacionada aos custos de manutenção e calibração dos instrumentos localizados na área de produção, pois, como estes equipamentos estão instalados em ambientes hostis, normalmente sofrem uma degradação acelerada, o que pode gerar leituras de campo erradas, dificultando a ação dos operadores. Em contrapartida, dentre os métodos inteligentes mais aplicados em processos industriais químicos, destacam-se as redes neurais artificiais. Esta estrutura se inspira nos neurônios biológicos e no processamento paralelo do cérebro humano, tendo assim a capacidade de armazenar e utilizar o conhecimento experimental que for a ela apresentado. Apesar do bom resultado que a estrutura de redes neurais gera, existe uma desvantagem relacionada à necessidade de re-treinamento da rede quando o processo muda seu ponto de operação, ou seja, quando a matériaprima sofre algum tipo de mudança em suas características físico-químicas. Como solução para este problema, foi elaborado um método híbrido que busca reunir as vantagens de uma estrutura de redes neurais com a habilidade de um filtro estocástico, conhecido por filtro de Kalman estendido. Em termos práticos, o filtro atua em cima dos pesos sinápticos da rede neural, atualizando os mesmos em tempo real e permitindo assim que o sistema se adapte constantemente às variações de mudança de processo. O sistema também faz uso de pré-processamentos específicos para eliminar ruídos dos instrumentos de leitura, erros de escalas e incompatibilidade entre os sinais de entrada e saída do sistema, que foram armazenados em freqüências distintas; o primeiro em minutos e o segundo em horas. Além disso, foram aplicadas técnicas de seleção de variáveis para melhorar o desempenho da rede neural no que diz respeito ao erro de inferência e ao tempo de processamento. O desempenho do método foi avaliado em cada etapa elaborada através de diferentes grupos de testes utilizados para verificar o que cada uma delas agregou ao resultado final. O teste mais importante, executado para avaliar a resposta da metodologia proposta em relação a uma rede neural simples, foi o de mudança de processo. Para isso, a rede foi submetida a um grupo de teste com amostras dos sinais de saída somados a um sinal tipo rampa. Os experimentos mostraram que o sistema, utilizando redes neurais simples, apresentou um resultado com erros MAPE em torno de 1,66%. Por outro lado, ao utilizar redes neurais associadas ao filtro de Kalman estendido, o erro cai à metade, ficando em torno de 0,8%. Isto comprova que, além do filtro de Kalman não destruir a qualidade da rede neural original
Nowadays, scientific and industrial interest on the development of nonlinear control systems increases day after day. However, before these models become reliable, they must pass through a hard and expensive implementation process. In this way, studies involving decision support methods try to develop low cost intelligent applications to build up advanced industrial control systems with excellent results, as in the petrochemical industry. In the distillation of oil derivatives, for example, it is very common the use of laboratorial sample analysis to identify if a substance has its physical- chemistry characteristics in accordance to international production rules. Besides, the analyses results allow the adjustment of production plant instruments, so that the process reaches a thorough control, and, consequently, a final product with higher quality. However, although laboratory analyses are more accurate to evaluate final product quality, sometimes it demands many hours of analysis, delaying the adjustments in the production equipment. In this manner, the process efficiency is reduced and some products have its production period increased because they should have its composition corrected with other reagents. Another disadvantage is the equipments´ maintenance costs and calibration, since these instruments are installed in hostile environments that may cause unaccurate field measurements, affecting also operator´s action. On the other hand, among the most applied intelligent systems in chemical industry process are the artificial neural networks. Their structure is based on biological neurons and in the parallel processing of the human brain. Thus, they are capable of storing and employing experimental knowledge presented to it earlier. Despite good results presented by neural network structures, there is a disadvantage related to the need for retraining whenever the process changes its operational point, for example, when the raw material suffers any change on its physical-chemistry characteristics. The proposed solution for this problem is a hybrid method that joins the advantages of a neural network structure with the ability of a stochastic filter, known as extended Kalman filter. This filter acts in the synaptic weights, updating them online and allowing the system to constantly adapt itself to process changes. It also uses specific pre-processing methods to eliminate scale mistakes, noises in instruments readings and incompatibilities between system input and output, which are measured with different acquisition frequencies; the first one in minutes and the second one in hours. Besides, variable selection techniques were used to enhance neural network performance in terms of inference error and processing time. The method´s performance was evaluated in each process step through different test groups used to verify what each step contributes to the final result. The most important test, executed to analyse the system answer in relation to a simple neural network, was the one which simulated process changes. For that end, the network was submitted to a test group with output samples added to a ramp signal. Experiments demonstrated that a system using simple neural networks presented results with MAPE error of about 1,66%. On the other hand, when using neural networks associated to an extended Kalman filter, the error decreases to 0,8%. In this way, it´s confirmed that Kalman filter does not destroy the original neural network quality and also adapts it to process changes, allowing the output inference without the necessity of network retraining.

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Chobot, Ivan. "Drobné prachové částice v plynných produktech spalování." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230414.

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Goal of this dissertation is introduce the problem of small dust particles present in the gaseous products of combustion. Further I´m looking technologies cyclone and an electrostatic filter to capture small particles and comparing the effectiveness of separability. Dissertation is concluded by designed cyclone and an electrostatic filter.

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YAMAMOTO, Kazuhiro, Shingo SATAKE, Hiroshi YAMASHITA, Akira OBUCHI, and Junko UCHISAWA. "Simulation on Soot Oxidation with NO2 and O2 in a Diesel Particulate Filter." The Japan Society of Mechanical Engineers, 2007. http://hdl.handle.net/2237/9385.

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Huang, Baitong. "Comparison of Pre- and Post-treatments of Sugarcane Industry By-products to Increase Biomethane Production." Thesis, Linköpings universitet, Institutionen för tema, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-170583.

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Even though the Brazilian ethanol and sugar production system (based on sugarcane industry) have been providing large amounts of bioenergy, the extensive amounts of organic wastes generated cannot be ignored when it comes to sustainability. Using these biomasses to produce biomethane through anaerobic digestion has been proven as a promising way to tackle this issue. This study investigated the biomethane potential of the co-digestion of these biomasses: SF (sugarcane straw : filter cake = 8:2), SFV (sugarcane straw : filter cake : vinasse = 1:4:45), and D (digestate separated from AD of SFV). Three treatments autoclaving (AU), alkaline (AL) treatment using 6% (w/w) NaOH and the combination of these two (AUAL) were then conducted on SF and SFV as pre-treatments; on D as post- treatments. In the biomethane potential tests of untreated material, the highest methane yield was achieved by SFV with 275.28 ± 11 N ml CH4/g VS, followed by SF with 223.25 ± 10 N ml CH4 g-1 VS, substrate D also resulted in a methane potential of 144.69 ± 2 N ml CH4 g-1 VS. As pre-treatments, AL and AUAL both showed increase in methane yield (between 36.0% and 49.1%) and methane production rate. As post-treatments, AU, AL and AUAL showed distinctive results in methane production, with 33.8%, 99.8% and 128.8% increase, respectively. In comparison with pre-treatment, post-treatment showed a better performance in increasing methane production. The following feeding experiments performed in continuous stirred-tank reactors showed that AL treatment led to an average of 248% increase in methane yield.
Sugarcane waste: towards a zero C emission in the Brazilian bioenergy sector

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Tatangsurja, Hendra. "Digital filter design using stored product ROMs." Thesis, University of Ottawa (Canada), 1987. http://hdl.handle.net/10393/5332.

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Levickaitė, Giedrė. "Sorbentų naudojimo paviršinėms nuotekoms valyti tyrimai ir analizė." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20110620_141622-97641.

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Didžiausiais paviršinių nuotekų teršalais laikomi naftos produktai ir skendinčiosios medžiagos. Pastarąsias galima nesunkiai pašalinti taikant tradicinius paviršinių nuotekų valymo metodus, tokius kaip nusodinimas, o naftos produktų šalinimui reikalingas antrinis nuotekų valymas. Vienas efektyviausių NP šalinimo iš nuotekų būdas yra filtravimas pro sorbuojančiosios medžiagos filtrą. Nors šiuo būdu valant nuotekas galima pasiekti didelio teršalų šalinimo efektyvumo, praktiškai dažnai susiduriama su problema, kai į eksploatuojamuosius valymo įrenginius nuotekos atiteka dideliais greičiais ir teršalai nėra iki galo pašalinami. Todėl šiame darbe buvo atliktas trijų skirtingų sintetinių sorbentų („Fibroil, „Duck“, „Reo-dry“) efektyvumo šalinti iš paviršinių nuotekų naftos produktus ekstremaliomis sąlygomis (esant dideliems greičiams) eksperimentinis tyrimas. Atlikus bandymus su dirbtinėmis ir realiomis paviršinėmis nuotekomis laboratoriniame stende, nustatyta, kad visų trijų sorbentų efektyvumas šalinti NP yra panašus ir skendinčiosios medžiagos bei nuotekų drumstumas neturi įtakos NP šalinimo efektyvumui. Tačiau „Fibroil“ sorbentą naudojant kaip filtro užpildą, 30 m/h greitį galima išlaikyti gerokai ilgiau nei su sorbentais „Duck“ ir „Reo-dry“ ir šį sorbentą naudoti ekonomiškiausia. Darbą sudaro 8 dalys: įvadas, darbo aktualumo aprašymas, literatūros apžvalga, tiriamojo darbo metodikos aprašymas, eksperimeto rezultatai, rekomendacijos ir išvados bei literatūros sąrašas. Darbo... [toliau žr. visą tekstą]
Suspended solids and oil products are considered as the most important pollutants in the storm water. As suspended solids can be easily retained from storm water by simple sedimentation, for oil products it is usually needed to have a secondary treatment: filtration through sorbents media. Although storm water filtration through a sorbent filter gives high treatment efficiency, it is usually impossible to ensure the right speed of storm water coming to the treatment facilities (it is usually too high to ensure an efficient sorption). For this reason the research and analysis of three different synthetic sorbents („Fibroil“, „Duck“, „Reo-dry“) were performed with artificial and real storm water in the laboratory under extreme conditions (filtration speed 30 m/h). According to the results of the experiment, all three sorbents have similar treatment efficiency and suspended solids and turbidity has no impact on oil products removal efficiency. But it is more efficient to use “Fibroil” and it is suitable for filtration under 30 m/h speed much longer than sorbents “Duck” and “Reo-dry”. Structure: introduction, relevance, methodology, results of the experiment, recomedations conclusions and references. Thesis consist of: 55 p. text without appendixes, 21 pictures, 8 tables, 39 bibliographical entries.

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Andersson, Egerlid Axel, and Fredrik Westin. "Design of filter cloth analyser : Development of a portable filter cloth selection tool for filters used to regenerate the acid used in the pickling process during the production of stainless steel." Thesis, Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-71474.

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The stainless steel industry is an industry which manufactures one of the most used ma-terials in the world. Even though the vast size of the industry many might not reflect werethe steel comes from when buying their IKEAcutlery etc. But in fact this industry is moreintricate and complex than one might think.During the manufacturing process, the steelgoes through several processes. One of thoseprocesses is done by treating the steel withstrong acid. This chemical process is calledpickling. The pickling process is what createsthe characteristic smooth and shiny surface ofa product made in stainless steel.This thesis is about the development of a testunit that is able to effectively test the ASRA(Acid Sludge Removal Apparatus) filter cloths.The ASRA is a filtration system developed by Scanacon in Stockholm that filtrates and puri-fies acid that is used during the pickling pro-cess of a steel manufacture process. Today, it is complicated, time consuming and dangerous totest and evaluate different filter cloths in orderto find the cloth that provides the best result,since the tests has to be conducted on the realsystems. The aim of this thesis was therefore tosolve these problems. Scanacon wanted to findan alternative solution, that would not includeinteraction with the real filtration system. Theyalso wanted a portable and safe solution. To solve the problem a iterative design pro-cess called RDCD which stands for research, design, create & delivery was developed. Theprocesses was heavily influenced by the CDIO process (Conceive, Design, Implement & Ope-rate). After the research phase was conducted it was decided that a small filter analysis productwould be the best way to solve the problem. The product was then developed one com-ponent at a time. During the project several prototypes and test was created and conductedin order to validate the design.The result is a small filtration unit speciallydesigned to simulate the ASRA system. Theproduct is able to rapidly test various filtercloths in an easy way, without putting the user in harm’s way. After the tests has been perfor-med can the user can identify which cloth that worked the best. The product is small enoughto be possible to be carried in a hard case bag,which in turn affords portability.
Stålindustrin är en industri som tillverkar ettav de mest använda materialen i världen. Trotsindustrins enorma storlek är det kanske intemånga som reflekterar varifrån stålet kommerifrån när man köper exempelvis IKEA bestick.Men faktum är att den här industrin är mycketmer invecklad och komplex än vad man kan tro. Under tillverkningsprocessen går stålet ige-nom flera processer. En av de här processerna genomförs genom att behandla stålet med starksyra. Den kemiska processen kallas för betningoch är det som ger en produkt tillverkad i stålden karaktäristiska lena och glänsande ytan. Den här examensrapporten handlar om ut-vecklandet av en test enhet som effektivt kan testa filter dukarna till ASRA (Acid SludgeRemoval Apparatus) systemet. ASRA systemetär ett filtreringssystem utvecklat av Scanaconi Stockholm som filtrerar och renar syran som används under betningsprocessen vid stål-tillverkning. Idag är det komplicerat, tidskrä-vande och farligt att testa och utvärdera olika filterdukar för att ta reda på vilken duk somger bäst resultat, eftersom att testerna måstegenomföras på de riktiga systemen. Målet fördet här examensarbetet var därför att lösa dehär problemen. Scanacon ville ha en alternativlösning som inte kräver interaktion med deriktiga systemen. De ville också ha en portabeloch säker lösning. För att lösa problemet utvecklades en itera-tiv designprocess kallad RDCD som står för research, design, create & delivery. Processen var tungt influerat av CDIO (Conceive, De-sign, Implement & Operate) processen. Efter att researchfasen var genomförd bestämdesdet att en liten filteranalysatorprodukt var detbästa sättet att lösa problemet på. Produktenutvecklades sedan en komponent i taget. Underprojektets gång har flera prototyper byggts och flera tester genomförts för att validera designen. Resultatet är en liten filtreringsenhet som är specialdesignad för att simulera ASRA syste-met. Produkten kan snabbt testa oliak filterdu-kar på ett enkelt sätt, utan utsätta användaren för fara. Efter att testerna genomförts kananvändaren identifiera vilken duk som funkatbäst. Produkten är tillräckligt liten för att fåplats i en hårdplast väska, vilket ger produktenden efterfrågade portabiliteten.

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Truffault, Laurianne. "Synthèse et caractérisation de nanoparticules à base d'oxydes de cérium et de fer pour la filtration des UV dans les produits solaires." Phd thesis, Université d'Orléans, 2010. http://tel.archives-ouvertes.fr/tel-00604174.

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L'objet de cette thèse est la synthèse et la caractérisation de nouveaux filtres UV inorganiques nanostructurés, efficaces dans le domaine des UVA. Dans ce contexte, nous avons choisi d'étudier le dioxyde de cérium (CeO2) et l'hématite (α-Fe2O3) en raison notamment de leurs propriétés optiques d'absorption des UV. Deux méthodes de synthèse ont été sélectionnées pour l'élaboration de ces oxydes, purs ou dopés, sous la forme de poudre nanométrique: la co-précipitation et le spray-pyrolyse. Les conditions optimales de synthèse ont été déterminées grâce à de la diffraction des rayons X et de l'analyse thermique. La structure cristalline ainsi que la granulométrie des échantillons obtenus ont été caractérisées par diffraction des rayons X et microscopies électroniques. La granulométrie et la morphologie des échantillons sont reliées aux méthodes de synthèse, aux conditions opératoires (atmosphère et température de calcination), à la nature et à la concentration des éléments dopants. Les propriétés optiques des échantillons suspendus dans de l'éthanol ont été étudiées par spectroscopie d'absorption UV-visible. Elles sont reliées à la granulométrie des échantillons ainsi qu'à des phénomènes localisés au sein de la maille cristallographique (changements de valence, présence de défauts). Les échantillons à base de CeO2 et α-Fe2O3 ont finalement été incorporés en émulsion solaire, à la place de ZnO, afin de tester leurs performances anti-solaires (SPF et FP-UVA) par mesure in vitro. Les résultats montrent que le ZnO peut être positivement remplacé dans les produits de protection solaire par l'oxyde de cérium ou de fer qu'ils soient purs ou dopés.

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Yearsley, Jonathan D. "Product family design using Smart Pareto filters /." Diss., CLICK HERE for online access, 2009. http://contentdm.lib.byu.edu/ETD/image/etd2687.pdf.

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Yearsley, Jonathan D. "Product Family Design Using Smart Pareto Filters." BYU ScholarsArchive, 2008. https://scholarsarchive.byu.edu/etd/1664.

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Product families are frequently used to provide consumers with a variety of appealing products and to help maintain reasonably low production costs for manufacturers. Three common objectives in the design of product families are used to balance the interests of both consumers and manufacturers. These objectives are to maximize (i) product performance, (ii) product distinctiveness as perceived by the consumer, and (iii) product commonality as seen by the manufacturer. In this thesis, three methods are introduced that use multiobjective optimization and Smart Pareto filtering to satisfy the three objectives of product family design. The methods are progressive in nature and begin with the selection of product family members using Smart filtering and develop through the establishment of scale- based product platforms to the design of combined scale- based and module-based product platforms. Each of the methods is demonstrated using a well-know universal electric motor example problem. The results of each method are then compared to a benchmark electric motor product family that was previously defined in the literature. Additionally, a pressure vessel example problem is used to further demonstrate the first of the three methods.

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Yamauchi, Kazuki, and Kazuhiro Yamamoto. "Numerical simulation of continuously regenerating diesel particulate filter." Elsevier, 2013. http://hdl.handle.net/2237/20043.

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Bender, Thorsten Onno. "Untersuchungen zum Effekt von Glukose, Glukosedegradationsprodukten und alternativen osmotischen Agenzien in Peritonealdialyselösungen auf Vitalität und Synthesefunktion peritonealer Mesothelzellen." Doctoral thesis, Humboldt-Universität zu Berlin, Medizinische Fakultät - Universitätsklinikum Charité, 2005. http://dx.doi.org/10.18452/15228.

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Konventionelle hitzesterilisierte, glukosehaltige Peritonealdialyselösungen (PDL) sind aufgrund ihres niedrigen pH-Wertes, ihrer hohen Glukosekonzentration und Osmolalität und ihres Gehaltes an Glukosedegradationsprodukten (GDP) bioinkompatibel. Alternativen zu glukosehaltigen PDL stellen aminosäuren- oder icodextrinhaltige PDL dar. Daneben enthalten auch neuere Glukose-PDL in Doppelkammersystemen aufgrund der Sterilisation von Glukose bei sehr niedrigem pH nur noch sehr geringe GDP-Konzentrationen. In dieser Arbeit wurden die akuten und chronischen Wirkungen verschiedener PDL auf humane peritoneale Mesothelzellen (HPMC) untersucht. Konfluente HPMC wurden mit den zu testenden PDL (glukosehaltige hitze- versus filtersterilisierte und konventionelle versus Doppelkammer-Glukose-PDL, 1% Aminosäuren-PDL und Icodextrin - alle bei neutralem pH-Wert) akut (1-4 Stunden Präinkubation) bzw. chronisch (bis zu 10 Tage) inkubiert. Die Zellvitalität (MTT-Assay) und IL-1beta-stimulierte Sekretion von IL-6 (Zellfunktion) wurden untersucht. Die akute und chronische Exposition von HPMC gegenüber hitzesteriliserten Peritonealdialyselösungen führte zu einer signifkanten Reduktion von Vitalität und Funktion der Zellen. Demgegenüber führte die Inkubation mit filtersteriliserten PDL und GDP-armen PDL zu einer weniger starken Beeinflussung von Vitalität und Funktion. Die aminosäurenhaltige PDL beeinflusste weder akut noch chronisch die Vitalität bzw. Funktion der Zellen negativ. Hingegen unterschied sich die icodextrinhaltige Lösung nicht wesentlich von der hitzesteriliserten PDL mit hohem Glukoseanteil. Die Verringerung des Gehaltes an GDP in PDL mittels Filtersterilisation bzw. alternativer Sterilisation in Zweikammerbeuteln hat einen positiven Einfluss auf Vitalität und Funktion von HPMC in vitro. Der Ersatz des osmotischen Agenz hingegen bedeutet nicht zwansgläufig eine bessere Biokompatibilität.
Conventional heat-sterilized glucose-containing peritoneal dialysis fluids (PDF) are bioincompatible due to their acidic pH, high glucose concentration and resulting hyperosmolality, and the presence of glucose degradation products (GDP). Alternatives to these solutions are PDL containing amino acids or icodextrin as the osmotic agent. Furthermore, novel glucose-based PDF contain only trace amounts of GDPs due to the sterilisation of glucose at very low pH in a dual-chamber container system. The present study examines the acute and chronic effects of different PDL on human peritoneal mesothelial cells (HPMC). Confluent HPMC were exposed to the different test PDF (glucose containing heat- versus filter-sterilised PDF and conventional versus dual-chambered glucose PDF, 1% amino-acid PDF and icodextrin – all at neutral pH) in an acute (1-4 hours preincubation) and chronic (up to 10 days) cell culture model. Cell viability (MTT assay) and IL-1beta stimulated IL-6 (cell function) release were assessed. Acute and chronic exposure of HPMC to heat-sterilised PDF resulted in a significant reduction of viability and cell function. In contrast, the incubation of filter-sterilised PDF and dual chambered low GDP solution had only minor effects on cell viability and function. Neither viability nor cell function were negatively affected by the amino-acid PDF following acute and chronic exposure. However, incubation with icodextrin resulted in a similar degree of inhibition as compared to incubation with conventional heat-sterilised glucose PDF. In conclusion, removal of GDP from PDF either via filter-sterilisation or manufacture in dual chambered containers helps to conserve viability and function of HPMC in vitro. However, the replacement of the osmotic agent per se does not necessarily result in improved biocompatibility.

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Andersson, Filip, and Niklas Martinsson. "Filter cleaning device : for truck cab climate systems." Thesis, Linköpings universitet, Maskinkonstruktion, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-153638.

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Scania has identified a problem among certain costumers in very dusty environments. The air filters for their truck’s climate system need extensive maintenance, replacement or manual cleaning, because of dust frequently loading up the filters. In this thesis the problem has been analyzed in order to find a solution. The process was initiated by the usage of the black box method, where needed transformations were found, resulting in three needed technical systems. Thereafter, brainstorming was used to find concepts for each technical system. Concepts were compared and ranked against each other. For the most critical of the three systems, the cleaning action, prototypes were built of the four highest ranked concepts. These prototypes were then used to compare the performance between the concepts. The selected filter cleaning device consists of a method to analyze filter blockage, alert the driver when cleaning is needed and a system to clean the filter for the Scania climate system. The system consists of a pressure sensor used to measuring filter blockage, an air pulse system which cleans the filter and a controller unit to control the cleaning cycle and to inform the driver. The air pulse system has two main parts, a pulse valve and an air tank. The pulse valve is used for releasing the air accumulated in the air tank. The complete system is supplied with 8.5 bar from the internal air pressure system in the truck and a 24 V power supply, also located in the truck. A suggestion on how a final implementation can be done has been developed, with a minimized number of variants and modifications of parts already in production. A proof of concept was built and mounted in a truck to validate the complete system. Numbers on cleaning performance and sound levels have been produced. The proof of concept manages to remove the restriction created from dust by approximately 50 %. Aside from developing a suitable filter cleaning device, figures on when the filter needs to be cleaned have been identified. To keep a good working environment within the cab a pressure drop over the filter of 936 Pa is recommended as a point of cleaning. This is to maintain the needed airflow of at least 123 m3/h with two persons seated in the cab to not exceed regulated levels of CO2 within the truck cab.

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15

Білоусов, Олег Юрійович. "Фільтрувальні композити на основі пороутворюючих матеріалів різного генезису". Thesis, КПІ ім. Ігоря Сікорського, 2021. https://ela.kpi.ua/handle/123456789/40818.

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Дисертацію присвячено розвитку наукових засад хімічної технології виробництва пористих керамічних фільтрувальних матеріалів за умов розширення сировинної бази, підвищення експлуатаційної надійності та конкурентоспроможності. Досліджено склад, структуру і властивості поверхні різновидів вихідних матеріалів штучного та природного походження як сировини для виготовлення пористих фільтрувальних композитів поліфункціонального призначення. Сформульовані вимоги і розроблено нові раціональні склади фільтрувальних матеріалів на основі композицій сировини різного генезису при диференціації кількісного співвідношення компонентів, їх гранулометрії, звʼязуючих, умов формування та ступеню термічної обробки. Розроблено технологічні принципи застосування вихідних матеріалів різного генезису – керамічного шамоту та магматичних порід для виготовлення фільтрувальних композитів і внесено відповідні зміни в технічні умови на їх виробництво. Дослідно-промисловими випробуваннями на об’єктах промисловості та сільського господарства підтверджена ефективність виконаних науково-технічних розробок.
The thesis is devoted to the development of scientific bases of chemical technology of production of porous ceramic filter materials under conditions of expansion of raw material base, increase of operational reliability and competitiveness. Comprehensive solution of issues of industrial development, life support and environmental protection has necessitated the implementation of filtration and purification of air, gases and liquids using porous materials. At the same time, attention is paid to expanding the range of such materials, increasing the performance and operational reliability. Elements of porous ceramics, which were produced in Ukraine at the Slavyansky ceramic plant, became practically widespread in filtration and purification systems. However, the constant expansion of applications and technical requirements for porous ceramics requires further modernization of their technology based on the deepening of scientific ideas about the criteria for selecting raw materials, their physical and chemical properties and features of the structure of products. Known developments in the technology of porous ceramics are mainly based on the use of highly concentrated dispersed systems based on resource-intensive ceramic fireclay, made by high-temperature firing of refractory clays. The analysis of the filler as a factor influencing the formation of the structure and properties of the products is reduced to the variation of its particle size distribution. In most known developments, the structural characteristics of filter ceramics are limited by indicators of total or open porosity. The cleaning efficiency is associated with a decrease in pore diameter while reducing productivity. Further development of competitive national production, increasing the range and directions of use of porous ceramics are inextricably linked with the expansion of raw materials, development of new mass compositions, improvement of technological processes and equipment, absorption of scientific ideas about the connection composition - structure - properties in highly concentrated dispersed silicate systems. The aim of this work is to develop scientific and technical principles of national production of competitive porous ceramics waiting for cleaning, irrigation and aeration systems by expanding the raw material base, establishing patterns of formation of the pore structure of filter ceramics based on fillers of different genesis. A set of physicochemical and instrumental methods of analysis and standardized testing were used for research. Lyophilicity and wettability by polar and nonpolar liquid were evaluated by the improved technique of B.V. Deryagin. The structure and phase composition were determined using X-ray phase, electron microscopic and infrared methods of physicochemical analysis. Processing of experimental results was carried out using the methods of mathematical statistics. The composition, structure and surface properties of varieties of raw materials of artificial (ceramic fireclay) and natural (magmatic rocks) origin as the main raw material – fillers and man-made cutting additives for the manufacture of porous filter composites for multifunctional purposes have been studied. New rational compositions of porous ceramics based on raw materials of different genesis with differentiation of varieties and quantitative ratio of components, porous man-made additives and the degree of heat treatment have been created. Technological principles of application of initial materials of different genesis for production of elements of ceramics as filter composites taking into account an energy condition and lyophilicity of a surface of pore structure are developed. The design has been improved and the industrial production of porous ceramic elements for technical systems of aeration and water purification and soil irrigation has been made.

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Malmborg, Petter. "Engine air filter requirements : How different running conditions affect service life." Thesis, Karlstads universitet, Institutionen för ingenjörsvetenskap och fysik (from 2013), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-74614.

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The internal combustion engine requires clean air in order to operate without problems the entire service life. The air filter acts as a barrier between the ambient air ridden with particulate matter, and the sensitive interior of the engine. Several factors affect the air filter performance, such as pressure drop, efficiency, and dust holding capacity. Many external factors affect the air filter too, such as driving style, engine type, if the car is equipped with hybrid propulsion et cetera. The scope for this thesis work aims to extend the knowledge of air filtration for the customer, in this case, Volvo Cars. A comprehensive literature study along with benchmarking of competitors acts as a foundational approach. Regarding air filter service life, three parameters are identified as the most significant: dust holding capacity, efficiency and pressure drop over the filter element. Reverse engineering shows some competitor design decisions. A model of estimating air consumption is developed using a data-driven approach with real-world driving data as a basis. The model shows how much the actual air consumption varies between different markets and various engines. As a result, the service lifetime of air filters in certain cars with certain engines may be extended or allow for a smaller filter size for the same service lifetime.

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17

Bachelot, Morgane. "Contamination de moules (mytilus sp.) en milieu marin par des substances pharmaceutiques et produits de soin." Thesis, Montpellier 1, 2010. http://www.theses.fr/2010MON13505.

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Les substances pharmaceutiques et les produits de soin utilisés pour la protection de la santé humaine sont retrouvés dans tous les compartiments du milieu aquatique. Certaines de ces substances présentent des caractéristiques physico-chimiques ou pharmacologiques suggérant une capacité à se bioaccumuler comme les filtres UV EHMC et OC aux log Kow supérieurs à 5 ou les benzodiazépines diazépam et tétrazépam aux log de Kow de 2,82 et 3,20. L'objectif de ce travail de thèse a été d'évaluer la contamination des moules par 3 filtres UV et de 2 benzodiazépines. Pour cela, une méthode analytique a été mise au point et validée pour le dosage de ces substances dans les moules. Le dosage de l'EHMC et de l'OC a montré qu'en milieu côtier la contamination des moules in situ provient majoritairement des activités récréatives en période estivale et que cette contamination est augmentée dans des zones semi-fermées. Des expérimentations de bioaccumulation sur ces deux substances ont montré que les moules ne bioaccumulent pas ces filtres UV ; elles reflètent les niveaux de contamination en temps réel. Les niveaux de benzodiazépines dans les moules ne sont pas détectables en milieu côtier. Des expérimentations en conditions contrôlées ont montré que les moules absorbent les benzodiazépines. Cependant, elles les éliminent et probablement les métabolisent. L'utilisation de moules pour l'étude de la contamination par des substances émergentes permet l'identification de zones ou de périodes à risque élevé
Pharmaceutical and personal care products used for human health protection are detected in all aquatic ecosystems. Among them, some compounds have physico-chemical or pharmacological properties that suggest a bioaccumulation capability. It’s the case of the UV filters, EHMC and OC, with log Kow higher than 5 or pharmaceuticals like diazepam and tetrazepam, with log Kow higher than 2.82. The aim of these Phd works was to assess marine mussels contamination for UV filters and benzodiazepines. So, a new analytical method was developed and validated for the determination of these compounds in mussels. EHMC and OC analysis realized in mussels sampled in French coastal waters showed that mainly contamination came from recreational activities in summer season, and that semi-closed areas were more contaminated. Moreover, laboratory experiments showed that mussels had clearly not bioaccumulate these 2 UV filters. Contamination levels in mussels are controlled by water concentrations. Conversely, benzodiazepines were not detected in coastal mussels. However, laboratory experiments showed an accumulation of benzodiazepines in mussels, suggesting elimination and metabolization means. Mussels are nevertheless usefull bioindicators of marine contamination by emerging compounds, allowing to characterize higher risk areas or periods

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18

Wang, Jia. "POLYMERIC MICRO-/NANO-FIBERS AND FILTERS PRODUCED USING MELT-BASED TECHNOLOGIES." Case Western Reserve University School of Graduate Studies / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=case1464870852.

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19

Studziński, Waldemar. "Wpływ czynników utleniających i chlorujących na przemiany wybranych chemicznych filtrów UV." Rozprawa doktorska, Uniwersytet Technologiczno-Przyrodniczy w Bydgoszczy, 2019. http://dlibra.utp.edu.pl/Content/1274.

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Celem pracy było zbadanie przemian wybranych filtrów UV pod wpływem promieniowania, czynników utleniających i chlorujących oraz identyfikacja produktow transformacji. Przedmiotem zainteresowania była również ocena ekotoksykologiczna filtrów UV i ich produktów degradacji
The aim of the doctor's thesis was to investigate transformations of selected UV filters under the influence of radiation, oxidizing and chlorinating agents and identification of transformation products. The subject of interest was also the ecotoxicological evaluation of UV filters and their degradation products

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20

Moosberg-Bustnes, Helena. "Fine particulate by-products from mineral and metallurgical industries as filler in cement-based materials /." Luleå, 2003. http://epubl.luth.se/1402-1544/2003/36.

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21

Mezgebe, Bineyam. "Innovative Biological Destruction of Hazardous Chlorinated and Brominated Volatile Disinfection By-products using Bio Trickling Filters." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1515505465180454.

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22

Sawitzki, Martin. "The Effects of Structured Products." St. Gallen, 2007. http://www.biblio.unisg.ch/org/biblio/edoc.nsf/wwwDisplayIdentifier/05600523001/$FILE/05600523001.pdf.

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23

Heim, Mathias. "Assessing returns of structured products." St. Gallen, 2008. http://www.biblio.unisg.ch/org/biblio/edoc.nsf/wwwDisplayIdentifier/01280742001/$FILE/01280742001.pdf.

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24

Laurent, Anne. "Etude "in vitro" de la rémanence de produits solaires." Paris 5, 1992. http://www.theses.fr/1992PA05P235.

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25

Leslie, Daniel C. "Transformation of UV-Filtering Agents in the Presence of Aqueous Chlorine: Kinetics and Transformation Products." University of Akron / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=akron1306282546.

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26

Tonini, Federico. "Bioconcentration of selected personal care products in Ruditapes philippinarum (Manila clam)." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.

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The Bioconcentration Factor (BCF) is the principal source of information used to assess and regulate the potential hazard and risk for a chemical that has the potential to bioaccumulate in the marine environment, according to the Marine Strategy Framework Directive (MSFD). The main objective of this thesis was to estimate the BCFs of two different emerging contaminants in Ruditapes philippinarum (Manila clam) under controlled laboratory conditions: the UV filter 4-methylbenzylidene camphor (4-MBC) commonly used in skincare products, and the artificial sweetener Acesulfame potassium (ACE-K) used as a food additive. Ruditapes philippinarum organisms were exposed directly to 4-MBC and ACE-K nominal concentration of 1, 10 and 100 μg L-1 during 10 days. Bioconcentration factors (BCFs) were estimated according to 3 different models for both compounds. The 4-MBC estimated BCFs fall in range of 61553 - 539143 L Kg-1, showing that this compound is very bioaccumulative and could also undergo biomagnification in the marine food chain. On the contrary, estimated ACE-K BCF is consistently lower, in order of 7 L Kg-1 for the nominal exposure concentration of 100 μg L-1. The low ACE-K BCF could be explained by its high solubility in water and thus a rapid metabolization by clams during the experiments. In summary, future research focusing on the marine environment is needed on these two emerging compounds.

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27

Guise, Anne-Emmanuelle. "Incorporation d'un filtre solaire dans les microsphères et essais de libération "in vitro" à partir d'une forme dermique." Paris 5, 1992. http://www.theses.fr/1992PA05P218.

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28

Scherbakoff, Natalia. "Rheological, interfacial and morphological changes produced by fillers in immiscible blends." Case Western Reserve University School of Graduate Studies / OhioLINK, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=case1060353014.

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29

Stieger, Remo. "Analysis of commodity based structured products." St. Gallen, 2008. http://www.biblio.unisg.ch/org/biblio/edoc.nsf/wwwDisplayIdentifier/02604528002/$FILE/02604528002.pdf.

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30

Shajii, Leylanaz. "Isolation and identification of biodegradation products released from dental composite resins with varying concentrations of resin and filler." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ29385.pdf.

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31

Ганошенко, О. М. "Зниження техногенного навантаження на навколишнє середовище при утилізації відпрацьованих автомобільних масляних фільтрів". Thesis, Полтавський нац. техн. ун-т ім. Ю. Кондратюка, 2019. http://essuir.sumdu.edu.ua/handle/123456789/74948.

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Дисертаційна робота присвячена розв’язанню актуальної науковоприкладної задачі у галузі екологічної безпеки – зниження техногенного навантаження на навколишнє середовище при утилізації відпрацьованих автомобільних масляних фільтрів за рахунок попереднього оброблення фільтрувального паперу мийним розчином з вилученням залишкового масла перед подальшим термічним знешкодженням. Результати роботи пройшли достатню апробацію та мають упровадження, що підтверджено відповідними актами. Експериментально підтверджено факт негативного впливу відпрацьованих автомобільних масляних фільтрів на навколишнє середовище для умов Полтавської області. Тому на першому етапі комплексної технології утилізації потрібно організувати їх збирання. Для цього запропоновано контейнерний спосіб роздільного збору відпрацьованих автомобільних масляних фільтрів, який дозволить здійснювати їх попереднє сортування та роздільний збір за типорозмірами і відділити відпрацьоване масло з подальшим його зливом. Конструкція контейнера захищена патентом на корисну модель. Експериментальні дослідження щодо вибору мийного засобу дали змогу визначити, що найбільш перспективним мийним реагентом для розв’язання поставленої задачі виявився перкарбонат натрію Na2CO3∙1,5H2O2. З метою визначення максимальної ефективності очищення фільтрувального паперу відпрацьованих автомобільних масляних фільтрів розроблено математичну модель та одержано стаціонарну (сідлову) точку, що визначила оптимальне співвідношення параметрів технологічного процесу. Проведено оцінювання розробленої технології на відповідність екологічним вимогам, яке показало, що попереднє оброблення фільтрувального паперу мийним розчином дозволяє зменшити техногенне навантаження на навколишнє середовище. Так уміст відпрацьованого масла знижується на 55%, а кількість забруднювальних речовин у димових газах на: сульфур (IV) оксиду – 89%, нітроген (IV) оксиду – 15%, карбон (ІІ) оксиду – 66%, вуглецю (сажі) – 86%.
Диссертационная работа посвящена решению актуальной научноприкладной задачи в области экологической безопасности – снижение техногенной нагрузки на окружающую среду при утилизации отработанных автомобильных масляных фильтров за счет предварительной обработки фильтровальной бумаги моющим раствором с извлечением остаточного масла перед термическим обезвреживанием. Результаты работы прошли достаточную апробацию и имеют внедрения, что подтверждено соответствующими актами. Экспериментально подтвержден факт негативного влияния отработанных автомобильных масляных фильтров на окружающую среду для условий Полтавской области. Поэтому на первом этапе комплексной утилизации нужно организовать их сбор. Для этого предложен контейнерный способ раздельного сбора отработанных автомобильных масляных фильтров, который позволит осуществлять их предварительную сортировку и раздельный сбор по типоразмерам, отделить отработанное масло с последующим его сливом. Конструкция контейнера защищена патентом на полезную модель. Экспериментальные исследования по выбору моющего средства позволили определить, что наиболее перспективным моющим реагентом для решения поставленной задачи оказался перкарбонат натрия Na2CO3∙1,5H2O2. С целью определения максимальной эффективности очистки фильтровальной бумаги отработанных автомобильных масляных фильтров разработана математическая модель и получена стационарная (седловая) точка, которая определила оптимальное соотношение параметров технологического процесса. Проведена оценка разработанной технологии на соответствие экологическим требованиям, которая показала, что предварительная обработка фильтровальной бумаги моющим раствором позволяет уменьшить техногенную нагрузку на окружающую среду. Так содержание отработанного масла снижается на 55%, а количество загрязняющих веществ в дымовых газах: серы (IV) оксида – 89%, азота (IV) оксида – 15%, углерода (II) оксида – 66%, углерода (сажи) – 86%.
The thesis is devoted to the actual problem of reducing the technology-related load on the environment at the disposal of waste automobile oil filters by preliminary filter paper processing by means of a washing solution with the residual oil extraction before further thermal decontamination. The results of the research have been sufficiently tested and implemented, which is confirmed by the relevant acts. The fact of negative influence of waste automobile oil filters on the environment for the Poltava region conditions has been experimentally confirmed. Therefore, at the first stage of integrated recycling technology, it is necessary to organize their сollecting. For this purpose, a container method for the separate collection of waste automobile oil filters is proposed, which will allow to pre-sort them and collect separately according to standard sizes and separate the waste oil with its subsequent drain. The design of the container is protected by a utility model patent. Experimental research on the detergent choice has made it possible to determine that the most promising detergent reagent for solving the problem is sodium percarbonate Na2CO3∙1,5H2O2. In order to determine the maximum efficiency of cleaning the filter paper of the waste automobile oil filter, a mathematical model was developed and a stationary (saddle) point was obtained that determined the optimal ratio of the technological process parameters. The evaluation of the developed technology for compliance with ecological requirements has been carried out. It showed that the preliminary treatment of filter paper with a washing solution can reduce the technology-related load on the environment. So the amount of waste oil is reduced by 55%, and the amount of pollutants in fume gases is: sulfur dioxide – 89%, nitrogen dioxide – 15%, carbon monoxide – 66%, soot – 86%.

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32

Sevagee, Christina R. "The development and performance evaluation of spool wound cartridge filters produced from novel fibres." Thesis, University of Sheffield, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434602.

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33

Wang, Li. "Enhancing performance, durability and service life of industrial rubber products by silica and silane fillers." Thesis, Loughborough University, 2007. https://dspace.lboro.ac.uk/2134/10798.

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Typical rubber compounds used to manufacture industrial products such as tyres, hoses, conveyor belts, acoustics, shock pads, and engine mountings contain up to eight classes of chemical additives· including curing agents, accelerators, activators, processing aids, and antidegradants. The cure systems in these articles often consists of primary and secondary accelerators, primary and secondary activators, and elemental sulphur. Recent legislation impacting upon the working environment, safety and health has imposed a considerable burden on the manufacturers of rubber compounds to meet various obligations. The selection of raw materials and manufacturing processes that do not harm the environment is of great importance. A novel technique for preparing rubber formulations using crosslinking nanofillers such as silanised precipitated silica has been developed in this research. The silica surfaces were pre-treated with bis[3-triethoxysilylpropyl-] tetrasulphane coupling agent (TESPT).· TESPT is a sulphur containing bifunctional organosilane which chemically adheres silica to rubber and also prevents silica from interfering with the reaction mechanism of sulphur-cure systems. The tetrasulphane groups of the TESPT are rubber reactive and react in the presence of accelerator at elevated temperatures, i.e.140 -260°C, with or without elemental sulphur being present, to form crossIinks in rubbers containing chemically active double bonds for example styrene-butadiene rubber (SBR) and polybutadiene rubber (BR) .. SBR and BR rubber compounds containing 60 phr of TESPT pre-treated silica nanofiller were prepared. The silica particles were fully dispersed in the rubber, which was cured primarily by using sulphur in TESPT. The reaction between the tetrasulphane groups of TESPT and the rubbers was optimised by incorporating different accelerators and activators in the rubber. The mechanical properties of the rubber vulcanisates such as hardness, tear strength, tensile strength, elongation at break, stored' energy density at break, abrasion resistance, modulus and cyclic fatigue life were increased significantly when the treated silica filler was added. The need for the accelerator and activator was dependent on the composition of the rubber. Interestingly, the rubbers were fully cured without the use of elemental sulphur, secondary accelerator and secondary activator. As a result, a substantial reduction in the use of the curing chemicals was achieved without compromising the important properties of rubber compounds which are essential for maintaining long life and good performance of industrial rubber products in service. This approach has also helped to improve health and safety within the workplace and minimise harm to the enviromnent.Furthermore, a significant cost saving was achieved after reducing the number of curing chemicals in the rubber.

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Koenig, Christian. "Structured Gambling Products and Behavioral Financial Engineering." St. Gallen, 2007. http://www.biblio.unisg.ch/org/biblio/edoc.nsf/wwwDisplayIdentifier/00160986001/$FILE/00160986001.pdf.

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Lang, Mathias. "On the Categorization of Structured Products in Finance." St. Gallen, 2009. http://www.biblio.unisg.ch/org/biblio/edoc.nsf/wwwDisplayIdentifier/05604715001/$FILE/05604715001.pdf.

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Mohr, Christopher. "Power Risk Management with Derivatives and Structured Products." St. Gallen, 2007. http://www.biblio.unisg.ch/org/biblio/edoc.nsf/wwwDisplayIdentifier/05600515001/$FILE/05600515001.pdf.

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Dumez, Catherine. "Les pigments minéraux utilisés dans les produits solaires." Paris 5, 1997. http://www.theses.fr/1997PA05P212.

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Turbyville, Thomas Jefferson. "Using Phylogenetically Conserved Stress Responses to Discover Natural Products with Anticancer Activity." Diss., Tucson, Arizona : University of Arizona, 2005. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu%5Fetd%5F1078%5F1%5Fm.pdf&type=application/pdf.

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Ben, Reddad Khalid. "Absorption percutanée et métabolisme de filtres solaires." Paris 11, 1994. http://www.theses.fr/1994PA11XXXX.

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Cleary, Gerard Patrick. "Interpretation of UHF signals produced by partial discharges in oil-filled power transformers." Thesis, University of Strathclyde, 2005. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21575.

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Oil-insulated power transformers are key components of the electrical transmission network. Knowing the state of their insulation is therefore of considerable interest to utilities. Failure in transformers often occurs as a result of electrical breakdown in the insulation materials. Such breakdowns may occur following insulation damage caused over a substantial period of time by the cumulative adverse effects of partial discharge (PD) activity. Recognition of PD in power transformers is important because early detection can allow utilities to take appropriate preventative measures in order that costly failures do not occur. In this work, a range of on-line partial discharge (PD) measurement techniques are reviewed. Ultra high frequency (UHF) and measurements based on the International Electro-technical Commission (IEC) standard 60270 are considered to be the most suitable. UBF measurements have the advantage that PD can be located using time flight measurements, while IEC 60270-based measurements can be quantified in terms pC. A test cell is designed, and PD current pulses are measured when the insulating oil at the tip of a sharp, conducting protrusion breaks down. Current pulses are recorded using two different measurement circuits, and different pulse shapes are observed. The experiments are of fundamental significance because UBF signals are only excited when discharges occur on timescales of around 1 ns or less. Results demonstrate that the durations of current pulses in oil can be sufficiently short to cause the excitation of UHF signals. Characteristics of PD generated in air, new transformer oil and used transformer oil are compared. PD current pulses are measured simultaneously with both EEC 60270-based and UHF measurements systems. Since EEC 60270-based and UBF measurement systems operate on very different principles their responses to PD current pulses of known magnitude provides a useful basis for comparing the performance of both systems. A range of insulation defects that would cause concern in an operational power transformer are then investigated. Radiated UHF signals are measured simultaneously using two broadband electric field sensors. The spectral content and energy of rating measured using each sensor during both half cycles are shown to be useful methods to assist with the understanding of discharge behaviour. UHF PD signals are also measured in a phase-resolved form, and these are analysed in ways that provide evidence of the physical differences between insulation defects. First tests are carried out on a 1000 MVA, 400 kV/ 275 kV power transformer, and results demonstrate that the UBF measurement technique is a very promising approach for PD monitoring. The research contributes to the knowledge base required for the development of continuous monitoring systems for partial discharge and arcing in oil-filled power transformers.

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Mota, Jessica. "Effects of the organic UV filters, oxybenxone and 4-methylbenzylidene champor, on the photobiology of the hexacoral Zoanthus sp." Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/22789.

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Mestrado em Biologia Marinha
Coral reefs are extremely complex and productive ecosystems, providing habitat for thousands of marine species. Despite their ecological and socio-economic importance, coral reefs are globally threatened by natural and anthropogenic impacts. The discharge of domestic and industrial wastes contributes for the introduction of xenobiotics, namely organic UV filters, in marine ecosystems such as coral reefs, contributing for their degradation over the past few decades. It is estimated that approximately 40 % of coral reefs located along coastal areas are at risk of exposure to organic UV filters such as Benzophenone-3 (BP-3) and 3-(4-methylbenzylidene) camphor (4-MBC), two widely used compounds in sunscreen lotions and personal-care products. It is therefore important to evaluate the effects of these emerging contaminants on local species inhabiting the more affected areas, namely the intertidal environments. The genus Zoanthus (Anthozoa: Hexacorallia) contains numerous species abundant in coral reefs and intertidal areas of tropical and sub-tropical regions. These photosynthetic corals, which live in symbiosis with dinoflagellates of genus Symbiodinium, might have potential application as indicator organisms. The existing research in zoanthids ecology is however scarce in comparison with other cnidarian groups. In this study, we aimed to evaluate the effects of short-term exposure of Zoanthus sp. to BP-3 and 4-MBC. Zoanthus sp. mini colonies (4 – 6 polyps) were exposed to 4 concentrations (0.5; 1, 2 and 4 mg/L) of BP-3 and 4-MBC during 96 h. After exposure, mini colonies were photographed for polyp behavioral response evaluation, the photosynthetic efficiency of photosystem II was measured in vivo, through PAM fluorometry, and finally, the Symbiodinium sp. cells were quantified and normalized to Zoanthus sp. dry weight. Results suggested that Zoanthus sp. exposure to sub-lethal and environmentally relevant concentrations of BP-3 and 4-MBC induced behavioral reactions in the polyps (increase of closed polyps with increased concentrations), decreased photosynthetic efficiency and the number of endosymbionts. Beside the polyp behavioural response, tested organic UV filters proven to have potential to induce coral bleaching. Further ecotoxicological studies should be undertaken with other compounds and with different coral species, to evaluate the effect of these emergent contaminants on coral reefs, and identify UV filter compounds less harmful to the environment.
Os recifes de coral são ecossistemas extremamente complexos e produtivos, que fornecem habitat a milhares de espécies marinhas. Apesar da sua importância ecológica e socioeconómica, os recifes de coral estão globalmente ameaçados por impactos naturais e antropogénicos. A descarga de resíduos domésticos e industriais contribui para a introdução de xenobióticos, nomeadamente filtros UV orgânicos, nestes ecossistemas marinhos, como os recifes de corais, contribuindo para sua degradação nas últimas décadas. Estima-se que aproximadamente 40 % dos recifes de corais localizados ao longo das áreas costeiras correm o risco de exposição a filtros UV orgânicos, como a Benzophenona-3 (BP-3) e 3- (4-metilbenzilideno) cânfora (4-MBC), amplamente usados em protetores solares e produtos de cuidados pessoais. Por conseguinte, é importante avaliar os efeitos destes contaminantes emergentes nas espécies que habitam as áreas mais afetadas, nomeadamente as zonas intertidais. O género Zoanthus (Anthozoa: Hexacorallia) contém inúmeras espécies abundantes em recifes de corais e áreas intertidais de regiões tropicais e subtropicais. Estes corais fotossintéticos, que vivem em simbiose com dinoflagelados do género Symbiodinium, podem ter potencial aplicação como organismos indicadores. A pesquisa existente em ecologia de zoantídeos é, no entanto, escassa, em comparação com outros grupos de cnidários. Neste estudo, procuramos avaliar os potenciais efeitos nefastos da exposição a curto prazo de Zoanthus sp. a BP-3 e 4-MBC. Expuseram-se mini colónias (4 a 6 pólipos) de Zoanthus sp. a 4 concentrações (0.5; 1; 2 e 4 mg/L) de BP-3 e 4-MBC durante 96 h. Após exposição, as mini colónias foram fotografadas para uma avaliação da resposta comportamental dos pólipos, mediu-se in vivo a eficiência fotossintética do fotossistema II, através da fluorometria de pulso modulado (PAM) e, finalmente, as células de Symbiodinium sp. foram quantificadas e normalizadas para o peso seco de Zoanthus sp.. Os resultados sugeriram que a exposição de Zoanthus sp. a concentrações sub-letais e ambientalmente relevantes de BP-3 e 4-MBC, induziu reações comportamentais nos pólipos (aumento do número de pólipos fechados com o aumento das concentrações), diminuição da eficiência fotossintética e do número de endossimbiontes. Para além da alteração comportamental dos pólipos, os filtros UV orgânicos testados provaram ter potencial para induzir o branqueamento de corais. Estudos ecotoxicológicos adicionais devem ser realizados com outros compostos e diferentes espécies de corais, para avaliar o efeito destes contaminantes emergentes em recifes de corais e também para a identificação de filtros UV menos prejudiciais ao meio ambiente.

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Durand, Laurence. "Développement et formulations de produits solaires conditionnés sous forme d'aérosol." Doctoral thesis, Universite Libre de Bruxelles, 2010. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210131.

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L’exposition au soleil, et donc aux rayons ultraviolets, est de plus en plus fréquente chez l’homme dans les pays occidentaux. En effet, les modes de vie ont fortement changé ces dernières années, avec pour résultat une augmentation non négligeable des loisirs en extérieur. Ceci a pour conséquence une augmentation de l’apparition des cancers cutanés, dont le pronostic de survie est souvent mauvais et l’issue fatale. De plus, les traitements associés à ces maladies sont lourds et n’agissent pas toujours de façon efficace. Les campagnes d’information et de prévention face aux dangers du soleil restent donc les principales mesures efficaces pour lutter contre le cancer cutané lié à une surexposition au soleil. La recherche de nouveaux produits permettant de protéger de manière efficace la peau des effets néfastes des rayons UV reste donc un défi permanent et primordial pour la recherche dans l’industrie cosmétique.

Dans un premier temps, le travail a consisté à développer des nouvelles formulations de produits solaires contenant des concentrations élevées en filtres UV, conditionnées sous forme d’aérosol, celles-ci valables pour le marché européen. Une émulsion E/H et une émulsion E/Si ont donc été réalisées. Elles contenaient au final 27% de filtres UV pour l’émulsion E/H et 16,5% de filtres UV pour l’émulsion E/Si, dont 4% de filtres inorganiques pour les deux types d’émulsion. Leur viscosité était de 6800 mPa.s pour l’émulsion E/H et de 2800 mPa.s pour l’émulsion E/Si. Ces formulations étaient stables lorsqu’elles étaient conservées pendant 2 mois à 40°C et également lorsqu’elles subissaient 5 cycles de température entre 5°C et 40°C. La mise en aérosol de ces émulsions a nécessité l’utilisation de 22% de gaz propulseur (mélange :butane, propane, isobutane).

La taille des gouttelettes étant un paramètre important de la caractérisation des aérosols pour le choix des matériaux à utiliser ainsi que pour sécurité afin d’éviter toute inhalation pulmonaire, l’influence de différents éléments sur celle-ci a été étudiée. Nous avons ainsi montré que la concentration en gaz, la viscosité, la présence ou non de filtres inorganiques ainsi que le choix des valves et diffuseurs utilisés jouent un rôle dans la taille des gouttelettes émises, celle-ci ne pouvant pas être inférieure à 30 µm de diamètre. La taille des gouttelettes émises était supérieure à 50 µm avec pas plus de 0.1% ayant une taille inférieure à 10 µm et maximum 25% des gouttelettes ayant une taille comprise entre 10 et 30 µm.

Les produits formulés contenaient de grandes quantités en filtres solaires, organiques et inorganiques (27% pour l’émulsion E/H et 16,6% pour l’émulsion E/Si), il était donc important de vérifier qu’aucun des filtres présents dans les émulsions ne passaient à travers la peau lors de l’application des produits solaires. En effet, ceux-ci doivent rester à la surface de l’épiderme afin de maintenir l’efficacité des produits solaires et d’éviter des effets néfastes systémiques éventuels en pénétrant la peau. Une étude in vitro utilisant de la peau humaine excisée et des cellules de diffusion de Franz nous a permis de constater que les filtres inorganiques présents dans les formulations restaient en surface de la peau, et seulement deux des filtres organiques (l’EMC et MBBT) présentaient un potentiel de pénétration cutanée négligeable et non nocif pour la santé humaine (maximum 1,21 µg/ml/cm2 pour EMC et maximum 0,14 µg/ml/cm2 pour MBBT). De plus, après 24 h d’expérience, plus de 50% des filtres restaient à la surface de la peau, ce qui permettait de maintenir l’efficacité des produits solaires. Afin de mener à bien cette étude, des méthodes analytiques pour l’analyse simultanée des filtres solaires organiques d’une part, par CLHP (Chromatographie Liquide Haute Performance), et inorganiques d’autre part, par ICP-OES (Inductively Coupled Plasma - Optical Emission Spectrometry), ont été mises au point et validées.

Une étude in vivo non invasive, basée sur le prélèvement des couches successives du stratum corneum, a été réalisée par la suite. Cette dernière a été effectuée par la méthode du « tape stripping », qui utilise des disques adhésifs rigides, et sur 9 volontaires pendant une période de 8 h. Elle a permis de confirmer les résultats obtenus avec la méthode in vitro. Une bonne corrélation entre ces deux types d’étude a été observée.

Enfin, la dernière partie du travail a porté sur l’EMC, un des filtres organiques utilisé dans la plupart des produits solaires mis sur le marché et dans les émulsions E/H et E/Si formulées. Ce filtre présente une sensibilité à la lumière et aux rayons UV. L’encapsulation lipidique de celui-ci a donc été envisagée afin de produire des nanoparticules dont la matrice lipidique a pour but de protéger l’EMC contre une dégradation causée par les rayons UV. Trois lipides différents ont été investigués et ont montré des résultats positifs de protection vis-à-vis des rayonnements UV. En effet, après 2 h d’irradiation par les UV, une perte d’efficacité de 30% de l’EMC pur a été observée contre 10% à 21% pour l’EMC encapsulé par les différents lipides. De plus, les nanoparticules n’ont pas montré de potentiel d’augmentation de pénétration cutanée de l’EMC.

Doctorat en Sciences biomédicales et pharmaceutiques
info:eu-repo/semantics/nonPublished

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Braun, Sebastien. "Effets du soleil sur la peau : les filtres solaires." Paris 11, 1996. http://www.theses.fr/1996PA114203.

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Chamberland, Julien. "Étude des biofilms dans les systèmes de filtration en industrie laitière : mécanismes de formation, caractérisation et stratégies de contrôle." Doctoral thesis, Université Laval, 2018. http://hdl.handle.net/20.500.11794/31866.

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Tableau d'honneur de la Faculté des études supérieures et postdoctorales, 2018-2019.
La formation de biofilms a longtemps été négligée pour expliquer la diminution des performances à long terme des systèmes de filtration industriels à long terme. Les paramètres opératoires de ces systèmes étaient orientés dans le but de maximiser les flux de perméation, sans égard à l’aspect microbien, et les stratégies de nettoyage utilisées ne ciblaient que l’encrassement chimique des membranes. Des biofilms peuvent pourtant se développer à leur surface, et leur tolérance croissante face aux méthodes classiques de nettoyage les rend particulièrement difficiles à contrôler à long terme. Ces travaux de doctorat avaient pour but de mettre en évidence les paramètres qui affectent la croissance des biofilms se formant à la surface des membranes de filtration et ce, afin d’élaborer une stratégie opératoire, applicable en industrie, pour limiter leur développement. Avant ce projet, quelques études avaient démontré la problématique des biofilms, mais celles-ci étaient limitées à des analyses réalisées par des méthodes de culture (microbiologie classique) ou à des observations par microscopie, laissant dans l’ombre la majorité de l’écosystème microbien se développant à la surface des membranes de filtration. C’est pourquoi le premier défi scientifique consistait à développer une méthode d’analyse dressant un portrait global des bactéries composant ces communautés. Une approche métagénomique ciblant le gène codant pour l’ARN ribosomique 16S (amplicon sequencing) a donc été développée à cette fin. Cette méthode a permis de démontrer l’impact de facteurs tels que la nature du fluide filtré, le prétraitement thermique des fluides avant la filtration, la température d’opération, le type de matériau membranaire ou la durée opératoire sur la composition et la vitesse de formation des biofilms. La première partie des travaux a été réalisée à partir de membranes spiralées industrielles échantillonnées en fin de vie utile. Celles-ci ont d’abord révélé l’importance de la nature du fluide filtré sur la composition de l’écosystème bactérien persistant à la surface des membranes de filtration. Ces premières observations industrielles ont ensuite été validées dans un environnement contrôlé à partir de systèmes modèles de filtration tangentielle ou de type « bioréacteur » imitant l’environnement de filtration et le processus d’encrassement microbiologique des membranes. Ces systèmes ont montré comment la réalisation d’une pasteurisation des fluides avant la filtration affecte les proportions des bactéries thermorésistantes et thermophiles à la surface des membranes de filtration. Leur croissance était particulièrement rapide lorsque la filtration était réalisée à haute température (> 40 °C). À ce titre, les systèmes devraient être opérés moins de 10 h consécutives à 50 °C pour éviter la prolifération de ces bactéries. À la lumière de ces travaux, la température et la durée d’opération, ou encore, l’utilisation de membranes présentant une plus faible rugosité pour réaliser l’ultrafiltration de lactosérum sont des paramètres qui présentent un intérêt afin de ralentir le processus de formation des biofilms, voire de favoriser l’implantation d’une microflore « moins nuisible » à la surface des membranes. Cette thèse, réaliste au fait qu’il est probablement impossible d’éradiquer les biofilms des systèmes de filtration, s’inscrit dans un processus de réflexion sur la définition de la qualité microbiologique des produits laitiers industriels à l’ère de la métagénomique. Maintenant que les méthodes de détection moléculaires permettent une caractérisation précise des microorganismes de l’environnement laitier, la quasi-stérilité des systèmes autrefois recherchée n’est possiblement plus la solution la plus judicieuse pour assurer leur innocuité. Cette thèse amène ainsi une nouvelle vision sur les possibles méthodes de prévention des biofilms, lesquels pourraient se transformer en opportunité pour les industriels laitiers.
Biofilm formation was neglected in the past years to explain long-term performance decrease in industrial filtration systems. Indeed, their operating parameters were selected to improve permeation fluxes as a priority without taking into consideration microbial issues, and the cleaning strategies mainly targeted chemical fouling. However, biofilms can be formed at the filtration membrane surface, and their increasing tolerance to classical cleaning solutions makes them difficult to control in a long-term purpose. This doctoral work was done to evidence the parameters that affect the formation of biofilms on filtration membranes, in order to design an industrial strategy limiting their growth. Before this project, few studies had demonstrated the issue, but they were limited to classical culture-based approaches or to microscopy, which certainly overshadowed the major part of the bacterial ecosystem formed on filtration membranes. Solving this analytical issue and to draw a global portrait of the bacteria among these dairy biofilms represented the very first challenge to address. A targeted metagenomic approach targeting the 16S rRNA gene (amplicon sequencing) was developed. This method enabled to characterize the impact of filtration operational parameters such as the nature of the filtered fluid, the heat-treatment of the feed prior filtration, the feed temperature, the membrane type used to perform filtration or the process duration on the formation speed or the composition of biofilms. The first series of experiments consisted in a preliminary study involving industrial spiral-wound filtration membranes sampled at the end of their useful lifetime. These membranes revealed how the nature of the filtered fluid affects the composition of bacterial communities persisting on membranes following membrane cleaning. Industrial observations were later validated in a controlled environment through the conception of model filtration or bioreactor systems imitating the filtration environment and the membrane biofouling phenomenon. It was shown that the pasteurization of the feeds prior filtration increases the proportions of thermoduric and thermophilic bacteria on membranes. Their growth is particularly fast when filtration is performed at higher temperatures (> 40 °C). Consequently, filtration systems should never be operated more than 10 consecutive h at 50 °C to avoid the proliferation of these bacteria. According to the results obtained for this thesis, operational parameters such as the feed temperature, the duration of the filtration process or the use of a smoother membrane surface to perform whey ultrafiltration exhibited potential to reduce the biofilm growth speed, or even to favor the adhesion of “less detrimental” bacteria on membranes. This thesis, realistic to the fact that it may be impossible to eradicate biofilms from filtration systems, is in line with the reflection process to define the microbial quality of dairy products in the metagenomic era. Molecular detection methods now enable an accurate characterization of microorganisms living in the dairy environment. Systems sterility pursued in the past is possibly no longer the best way to ensure food safety. The new vision presented in this thesis introduces a new philosophy to prevent the negative impacts of biofilms, which could be turn into an opportunity for the dairy industry.

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Ruoss, Sven. "Product Placement als Werbeform Idee - Konzept - Wirkung /." St. Gallen, 2005. http://www.biblio.unisg.ch/org/biblio/edoc.nsf/wwwDisplayIdentifier/02600278001/$FILE/02600278001.pdf.

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Gormaz, Araya Juan Guillermo. "Extracto hidroalcohólico de Bluddleja globosa y extracto seco de Rosmarinus officinalis como preservantes de filetes de Oncorhynchus mykiss." Tesis, Universidad de Chile, 2005. http://www.repositorio.uchile.cl/handle/2250/105446.

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Memoria para optar al título de Bioquímico
La degradación química de los alimentos es un proceso espontáneo e inducido por efecto de la luz, el calor y la presencia de trazas de algunos iones metálicos de transición, factores que inducen la formación de especies reactivas del oxígeno (ROS). Con el objetivo de preservar los alimentos de la degradación química, la industria alimentaria a utilizado durante años principalmente BHT y BHA; sin embargo, recientes estudios de toxicidad han provocado restricciones de su uso a nivel internacional, lo que ha motivado la búsqueda de sustitutos, cuya inocuidad no pueda ser cuestionada. Una posible alternativa a los antioxidantes sintéticos son los extractos naturales de reconocida actividad antioxidante, la cual estaría dada principalmente por su capacidad de secuestrar radicales libres del oxígeno atribuible principalmente a su alta concentración de polifenoles. Estos antecedentes permiten postular que extractos naturales enriquecidos en polifenoles podrían proteger los alimentos de la degradación química, preservando así sus características nutritivas y organolépticas. El objetivo de este trabajo fue comparar la capacidad de BHT y los extractos de Bluddleja globosa (matico) y Rosmarinus officinalis (romero) de proteger los lípidos y el contenido tiólico de filetes de Oncorhynchus mykiss (trucha arcoiris). El BHT y los preparados de matico y romero inhibieron la lipoperoxidación y protegieron la disminución del contenido de tioles de homogeneizados de filetes de trucha arcoiris, ambos fenómenos inducidos por el sistema Fe3+/ascorbato. Los polifenoles de los antioxidantes serían los principales responsables de la protección del contenido tiólico, mientras que los compuestos o-difenoles-diterpénicos serían los responsables principales de la actividad antilipoperoxidante. Cabe señalar que estos principios activos naturales poseen efectos benéficos para la salud humana y animal. Por lo tanto, preparados enriquecidos en polifenoles y o-difenoles-diterpénicos no sólo actuarían como antioxidantes de alimentos, sino además, podrían contribuir a mejorar la calidad de vida de los consumidores
Chemical degradation is a spontaneous and induced process by light, heat and the presence of metallic ions traces, factors which induce the formation of oxygen reactive species (ROS). To preserve foods from chemical degradation, food industries have used for a long time principally BHT and BHA; however, toxicity studies recently have been published and the international use of these antioxidants are under study. A possible alternative to replace BHT and BHA could be the use of natural extracts as preserving agents. Natural extracts have antioxidant properties due to the high poliphenols concentration and their capacity to scavenger oxygen radicals. These data permit postulate that natural extracts enriched in poliphenols compounds may prevent chemical degradation of foods, so preserving their nutritive and organoleptic properties. The aim of this work was to compared the capacity of BHT, an hydroalacoholic extract of Buddleja globosa (matico) and a dry extract of Rosmarinus officinalis (romero) to prevent the oxidation of lipids and thiol groups present in Oncorhynchus mykiss (rainbow trout) stakes. BHT and the extracts of matico and romero inhibited the lipoperoxidation and prevented the thiol oxidation of Oncorhynchus mykiss stakes, both phenomenon induced by Fe3+/ ascorbate. Protection of thiol oxidation seems to be mediated by the poliphenols present in the natural extract, and the antilipoperoxidant action would be mediated by the o-diphenol-diterpene. It is necessary to note that natural active principles induce benefic effects on human and animal health. Thus, natural preparations enriched in poliphenols and o-diphenol-diterpene would act as food antioxidants and besides improving the health of consumers

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Lutz, Theresa Marie. "A Study of the Precursors for Disinfection By-Products on the CAP Avra Valley Recharge Project." Thesis, The University of Arizona, 2000. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_etd_hy0114_sip1_w.pdf&type=application/pdf.

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Böselt, Alexandra. "Financial Guarantees in Unit-Linked Life Insurance Products - A Behavioral Economics Perspective." St. Gallen, 2009. http://www.biblio.unisg.ch/org/biblio/edoc.nsf/wwwDisplayIdentifier/05609771101/$FILE/05609771101.pdf.

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Arias, Valdivia Francisco Fernando, and Mispireta Jorge Luis Huapaya. "Requisitos técnicos del Organismo Nacional de Sanidad Pesquera - SANIPES que dificultan la importación y comercialización del filete de tilapia congelado proveniente de un nuevo productor chino en función de la experiencia de la empresa Umi Foods S.A.C. durante los años 2017 - 2018." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2019. http://hdl.handle.net/10757/626294.

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El presente trabajo de investigación busca describir las dificultades que ha ocasionado el protocolo técnico de registro sanitario de importación de productos pesqueros y acuícolas congelados impuesto por la autoridad sanitaria competente del Perú respecto a la importación y comercialización del filete de tilapia congelado proveniente de un nuevo productor chino a partir de la experiencia de la empresa Umi Foods S.A.C., por lo tanto nuestro estudio se divide en cuatro (4) capítulos, los cuales son detallados a continuación. El primer capítulo se centra en el plan de investigación, por medio del cual planteamos la pregunta, el problema y los objetivos, tanto principales como específicos y la formulación de la hipótesis inicial de la investigación. El segundo capítulo da a conocer los antecedentes de la investigación, tanto nacionales como internacionales y el marco teórico del estudio, así como las restricciones para la importación y los requisitos para la comercialización del filete de tilapia congelado. El tercer capítulo se centra en la metodología de la investigación, donde detallamos el tipo, propósito, categorías, delimitación, diseño y tamaño de muestra de la investigación. Asimismo, en este capítulo desarrollamos las entrevistas de profundidad, las cuales serán de utilidad para el recojo de información. Finalmente, el cuarto capítulo se enfoca en el respectivo análisis y discusión de resultados de nuestra investigación para así encontrar los hallazgos y realizar tanto las conclusiones como las recomendaciones finales por medio del análisis de documentos y de la información obtenida mediante las entrevistas de profundidad desarrolladas en nuestro estudio.
The present research seeks to describe the difficulties caused by the technical protocol of import sanitary registration for frozen fishery and aquiculture products from the sanitary authority of Peru regarding the import and commercialization of frozen tilapia fillet that comes from a new Chinese producer and according to the experience of the company Umi Foods S.A.C., therefore our study is divided into four chapters that are detailed as below. The first chapter focuses on the planning research, which is about proposing the research question, the main and specific problems and objectives. In this chapter we also make known about the starting hypothesis of our working research. In the second chapter we present the national and international backgrounds and the theory framework of the research as well as the import restrictions and the commercialization requirements of the frozen tilapia fillet. The third chapter explains the methodology research, which we detail the type, purpose, categories, delimitation, design and sampling size of the research. Also, in this chapter we develop depth interviews that will be very useful for the research’s collecting information. Finally, the fourth chapter is about the respective analysis and discussion of the research´s results in order to get the findings of the study and make the final conclusions and recommendations according to the documents’ analysis and to the obtained information from held depth interviews in our research.
Tesis

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Liu, Shuyue S. M. Massachusetts Institute of Technology. "Adapting Consumer Report's product evaluation methods for particle removal, gravity non-electric and reverse osmosis water filters in the Indian marketplace." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/97798.

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Thesis: S.M., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2015.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 113-115).
Household Water Treatment and Storage (HWTS) products provides households that are drinking unimproved water supplies with a first line of defense against contaminants in their drinking water and those drinking improved water supplies with an additional barrier against potential risks. With the global water crisis becoming more and more severe, evaluation of HWTS technologies and products has become crucial to ensure they are used to remove impurities effectively. The goal of this thesis was to evaluate household water filters in the Indian marketplace as part of a larger research and technology evaluation to investigate the utilization and performances of different water filter models in both lab and field settings. This was achieved by comparative testing and research work done at Consumer Reports (CR) Headquarters in Yonkers, NY. This evaluation included the testing of three categories of filters: Conventional Particle Removal (cloth and mesh), Gravity Non-Electric (GNE) and Reverse Osmosis (RO) water filters. In total, 16 models were tested. The challenge water for all filter testing had these characteristics: 40+/-10 NTU turbidity and 1500+/-150mg/L total dissolved solids (TDS). When testing E.coli removal, deionized water was used as the base water and the concentration of E. coli was 10⁵ to 10⁶ MPN (Most Probable Number)/100mL. The comparative testing attributes that were evaluated include: E.coli removal, turbidity removal, TDS removal, clean water flow rate, RO % recovery, and filter lifetime with the end-of-life defined as when flow rate <1 L/hr. As a result of this product evaluation, the author determined that: 1) Cloth and mesh filters had limited effectiveness in reducing contaminants; 2) GNE filters had much better performance than cloth and mesh filters, but none of them had outstanding performance; 3) RO filters were shown to be quite effective in reducing turbidity (greater than 99.5%), TDS (greater than 97%), and E.coli (greater than 99.9999%). But, they produce a large amount of wastewater (around 3/4 of the feed water) which is a huge waste of precious water and a sustainability concern especially in a water scarce region.
by Shuyue Liu.
S.M.

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