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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Utvecklingen av ett produktsystem för bättre och billigare cancerdiagnostik : Framtagning av engångskassett och tillhörande basenhet för isolering av cirkulerande och andra suspenderade tumörceller / Development of a product system for better and more cost-effective cancer diagnosis : Design of a disposable cassette and associated base unit for isolation of circulating and other suspended tumor cells

Rauof, Goran, Jägerback, Jonas January 2012 (has links)
Det här examensarbetet består i ett produktutvecklingsprojekt som utfördes i samarbete med Liquid Biopsy AB. Syftet med arbetet var att utveckla ett engångskassettsbaserat produktsystem baserat på företagets patentsökta metod för isolering av cancer celler i suspension, inklusive cirkulerande tumörceller. Liquid Biopsy AB är ett svenskt utvecklingsbolag som baserat på ny och unik teknik, är oberoende av proteinmarkörer, använder cirkulerande tumörceller och andra suspenderade tumörceller för att möjliggöra bättre och billigare cancerdiagnostik. Examensarbetet har fokuserat på utvecklingen av engångskassetten, men parallellt arbete har även utförts med tillhörande basenhet. Ulrich och Eppingers produktutvecklingsprocess har utgjort grunden för den process som följts i arbetet, dock med ökat fokus på testning och utvärdering. För att få en bredare kunskapsbas inleddes arbetet med en marknads- och omvärldsanalys samt informationsinsamling om utmaningar och medicintekniska krav. För att tydligt definiera produktvisionen utfördes även undersökningar med potentiella användarna, om företagets patentsökta metod och befintliga prototyper samt framtida förbättringspotential. Det kassettkoncept som utvecklats bygger på användning av provrör av existerande standard, få tillverkningsprocesser och god användarvänlighet, något som samtliga varit av hög prioritet under arbetet. För att säkerställa att produktens flödessystem fungerar som tänkt utfördes tester under prototypframtagningen. Testningen visade att konceptet fungerar i stort sett som tänkt med avseende på flöden, dock förekom vissa toleransproblem som följd av den valda prototypframtagningsprocessen, och vissa andra viktiga egenskaper återstår att testa. Resultatet av utvecklingsprocessen är en första fysisk prototyp av engångskassetten och en funktionell partiell prototyp av basenheten, motsvarande gränssnittet mot engångkassetten, för att möjliggöra testning av engångskassetten. Slutsatsen av arbetet är att det framtagna produktsystemet har tydliga fördelar gentemot företagets befintliga prototyper: inklusive att en engångskassett framtagits, att denna kan utgöra underlag för en produkt, och att denna bland annat har väsentligt kortare processväg vilken i sin tur borde kunna leda till förkortad processtid. Utförd finansiell analys visar även att framtaget produktsystem kan säljas till konkurrenskraftiga priser och med en betydligt lägre instegskostnad än dagens konkurrerande produkter. / This thesis consists of a product development project conducted in collaboration with Liquid Biopsy AB. The purpose of this work was to develop a disposable cartridge-based product system based on the company’s patent-pending method for isolation of circulating tumor cells and other suspended tumor cells. Liquid Biopsy AB is a Swedish medical technology research company with a unique new rheological technology, that is independent of protein markers, using suspended cancer cells, including circulating tumor cells, allows better and cheaper cancer diagnostics than today. The thesis work has focused on the development of the disposable cassette, but parallel work has also been performed with the associated base unit. Ulrich and Eppingers product development process has made up the basis for the process being followed in the thesis work, with increased focus on testing and evaluation. The work began with a market analysis and information gathering on challenges and medical requirements. Several activities were also carried out in order to clearly define the product vision, including user-surveys, analysis of the company's existing prototypes, as well as potential for future improvements. The developed cartridge concept is based on the use of standard test tubes, few manufacturing processes and user-friendliness which all have been high priorities in this work. The cartridge concept consists essentially of various plastic materials and is adapted for manufacturing by injection molding. To ensure that the product’s flow system was operating as intended, tests were conducted during the prototype phase. Testing showed that the concept design flows largely as intended, yet with some tolerance problems as a result of the selected rapid prototyping process, while other essential properties remain to be tested. The result of the development process is a first physical prototype of the disposable cartridge and a partial functional prototype of the base unit to allow testing with the disposable cartridge. The conclusion of this thesis work is that the developed product system has strong advantages over the company’s existing prototypes, including a first version of a disposable cassette that has potential to form the basis of a mass-producible product, significantly shorter processing route which in turn should allow a reduction of the processing time. Financial analysis also indicates that the designed product systems can be sold at competitive prices and with a significantly lower entry cost than today's rivaling products.
22

Rozpoznávání markantních rysů na nábojnicích / Recognition of Important Features on Weapon Shells

Janáček, Matej January 2010 (has links)
The text covers the automated recognition and comparison of features on used cartridge cases, in order to increase e ectivity of similar manual ballistic systems. The work is addresing the issue of programming the application for automated recognition and comparison of features on used cartridge cases.
23

Determining ideal staple size for small intestinal surgery in cats

Hiebert, Elizabeth C. 08 March 2022 (has links)
Background: The use of stapling equipment for intestinal surgery in cats is rarely reported, and appropriate staple sizes for cat intestine are unknown. Objective: To determine staple cartridge sizes for thoracoabdominal (TA) and endoscopic gastrointestinal anastomosis (EndoGIA) that will simultaneously prevent leakage of small intestinal contents while also allowing for sufficient vascular permeability past the staple lines for intestinal healing. Methods: Two sizes of EndoGIA cartridges (2.0/2.5/3.0mm and 3.0/3.5/4.0mm) and two sizes of TA cartridges (2.5mm and 3.5mm), applied in a transverse manner across fresh cadaveric cat jejunum, were evaluated via intestinal burst pressure testing for maximum intraluminal pressure prior to leaking, and via infusion of an intravascular dye at normal arterial pressures to determine percentage of vascular patency past the staple lines. Vascular patency was compared not only from pre-and post-staple segments of the same intestinal sample, but also EndoGIA vascular patency was evaluated against TA vascular patency. Results: Two cats met study criteria. All samples had intraluminal burst pressures over twice the chosen minimum (of 30mmHg). Vascular patency post- staple line ranged from 0-90.8%, with the most consistently high numbers noted with the TA 3.5mm cartridges. No EndoGIA cartridge had a post- staple line vascular patency higher than 31.1%, and no intravascular dye was noted in any post- staple line sample in the EndoGIA 2.0/2.5/3.0mm group. Conclusions: While statistical analysis of the dataset was unable to be performed due to low numbers of samples for comparison, both intestinal intraluminal burst pressure trends and intravascular dye patterns suggested both the TA 3.5mm cartridge and (to a lesser extent) the 3.0/3.5/4.0mm EndoGIA cartridge could provide the ideal combination of intraluminal seal without restriction of vascular access for healing. The intravascular dye infusion technique, developed during this research, shows promise as a future instrument to determine vascular patterns around intestinal implants in cadaveric cat specimens. / Master of Science / Despite the regularity of feline small intestinal surgery, few reports exist of stapled anastomoses in cats, in part due to stapler size limitations. However, the recently developed endoscopic gastrointestinal anastomosis (EndoGIA) stapler shows promise as a future surgical tool for cats because it fits into cat intestine. In dogs, 3.5mm staples are often chosen for intestinal surgery; however, dog intestine is considerably thicker than cat intestine. The study goal was to evaluate not only intestinal burst pressures (the pressure at which repaired intestine leaks), but also the ability of fluids to flow through blood vessels that cross the staple lines of four stapler cartridge types from two staple lineages (EndoGIA 2.0/2.5/3.0mm, EndoGIA 3.0/3.5/4.0mm, TA 2.5mm, and TA 3.5mm). The central hypothesis was twofold. First, smaller stapler cartridge sizes (the EndoGIA 2.0/2.5/3.0mm and TA 2.5mm) would have higher intraluminal burst pressures when compared to the larger sizes (the EndoGIA 3.0/3.5/4.0mm). Second, larger stapler cartridges (the EndoGIA 3.0/3.5/4.0mm and the TA 3.5mm) would allow for increased flow of fluids in blood vessels past the stapler lines compared to the smaller cartridges (the EndoGIA 2.0/2.5/3.0mm and the TA 2.5mm). Two cats were included in the study. Trends in the data suggested that all components of the hypothesis might be proven with further data. However, due to the low number of cats acquired during the study period, the hypotheses could not be verified with statistics. The dye infusion technique to evaluate flow of fluids in blood vessels, developed during this research, shows promise as a future instrument to determine vascular patterns around intestinal implants. Future research should focus on acquiring more cats to have the ability able to perform statistical analyses (and prove the hypothesis), before proceeding with additional related studies.
24

Caractérisation et optimisation de la performance des cartouches d'ancrage AMBEX sous chargement soutenu

Polo, Luz January 2014 (has links)
Les systèmes d’ancrages adhésifs sont utilisés dans plusieurs applications en génie civil, notamment en réhabilitation et réparation des ouvrages d’infrastructure tels que des dalles de ponts, chaussées, tunnels, barrages, murs, poteaux, ainsi que dans certains travaux d’exploration géologique et minière. Un système d’ancrage adhésif comprend trois composants : l’élément d’ancrage : une barre d’armature ou une tige filetée ; le matériau adhésif : polymérique, cimentaire ou hybride ; et le substrat : en béton ou en maçonnerie. Les charges imposées sur les barres d’ancrage sont transmises au substrat par adhérence chimique (réactions) et liaison mécanique (interlock) entre les composants mentionnés. Le modèle de design d’adhérence uniforme établit que la performance structurale d’un système d’ancrage adhésif est déterminée par la contrainte de l’adhérence (τ), développée sur toute la surface de contact, entre les composants à l’intérieur du trou d’ancrage. Ce projet, en partenariat avec l’entreprise AMBEX, étudie et évalue la performance des systèmes d’ancrage avec adhésifs en matériau cimentaire, par rapport au comportement sous chargement continu. Pour ce faire, on a ancré des barres d’armature dans un substrat en béton conventionnel. Les deux adhésifs étudiés sont les cartouches d’ancrage AAC et ARC. On a tenu compte des paramètres géométriques et d’installation en assurant la rupture de l’adhérence lors des essais d’arrachement. On a évalué deux conditions en service: température ambiante (21ºC) et élevée (43ºC). On a effectué des essais statiques de traction et des essais sous chargement soutenu. Les résultats sont présentés dans des graphiques « chargedéplacement-temps », afin d’établir des prédictions futures de comportement. Le projet montre les avantages des ancrages adhésifs en matériau cimentaire, tels que le taux de fluage très faible sous chargement soutenu, et quelques limitations aussi, comme la variabilité des résultats à l’arrachement pour les ancrages avec la cartouche AAC. / Abstract : Adhesive anchoring systems are used in many civil engineering applications, including rehabilitation and repair of infrastructure such as bridge decks, roadways, tunnels, dams, walls, columns, and in some geological explorations and mining. An adhesive anchoring system consists of three components: the anchor: a reinforcing bar or a threaded rod; the adhesive material: polymeric, cementitious or hybrid; and a substrate of concrete or masonry. The loads applied on the anchor rods are transmitted by a chemical adhesion to the substrate (reactions) and mechanical interlock between the components mentioned. The design pattern of uniform adhesion establishes that the structural performance of an adhesive anchoring system is determined by the bond strength (τ) developed across the contact surface, between the components within the anchor hole. This project, in partnership with AMBEX, investigates and assesses the performance of an anchoring system, with an adhesive of cementitious material, related to the creep behaviour. To achieve this, steel rebars were anchored in a conventional concrete substrate. Two adhesives were evaluated: AAC and ARC cartridges. Geometrical and installation parameters were taken into account, to ensure bond failure during pullout tests. Two service conditions were studied: room temperature (21ºC) and high temperature (43ºC). Static tensile tests and creep tests were performed. The results are presented in graphs “load-displacement-time”, in order to make predictions of future behavior. The project shows the advantages of adhesive anchors made of cementitious material, as a feeble creep rate at sustained load, and also some limitations, as the variability of tension test results for anchors tested with AAC cartridge.
25

Dagvattenhantering inom starkt hårdgjord radhustomt med jord av begränsade infiltrationsegenskaper. / Stormwater management in strong hardened row house site with soil of limited infiltration properties.

Andersson, Rickard January 2016 (has links)
Syfte: Problemet med hårdgjorda ytor, som exempelvis asfalt och tak, är att de inte absorberar dagvattnet tillräckligt. Vidare leder detta till att gräsytor och andra absorberande ytor runt omkring måste ta hand om det dagvatten som inte de hårdgjorda ytorna kan tillvarata. Översvämningar i urbana miljöer har blivit allt vanligare på grund av kraftiga regn och stor andel hårdgjorda ytor. Detta leder till att ledningsnätet för dagvatten blir överbelastat. Därmed behövs väl fungerande utjämningsmagasin nära källan för att efterlikna naturens naturliga avrinningsförlopp. Målet var att utreda vilken eller vilka utjämningsmagasin som främst bör tillämpas i starkt hårdgjorda små radhustomter, med avseende på effektivitet, kostnad och underhåll, då jordmånen har begränsade infiltrationsegenskaper. Metod: De metoder som har använts för att svara mot målet är dokumentanalys, kvalitativ intervju och fallstudie. Dokumentanalysen fungerade som underlag för fallstudien och intervjuerna fungerade som bidragande empiri för fallstudien. Resultat: Det utjämningsmagasin som är att föredra är rörmagasin när anläggningsytan är begränsad och jordmånen har begränsade infiltrationsegenskaper. Konsekvenser: I problembeskrivningen beskrivs problemet med att det blir allt fler översvämningar i urbana miljöer på grund av de hårdgjorda ytorna och de kraftiga regnen. Vidare beskrivs det att ledningssystemet därför riskerar att bli överbelastat. Detta problem bekräftades även i intervjuerna. Arbetet löste inte vilket utjämningsmagasin som är att föredra för alla typer av fall, utan för fall där tomtytan är begränsad och där jordmånen har begränsade infiltrationsegenskaper. Lösningen på problemet är därför att rörmagasin är det utjämningsmagasin som är att föredra vid lokalt omhändertagande av dagvatten vid dessa förhållanden. Vid tillämpning av detta resultat i verkligheten rekommenderas det att använda kostnaderna per meter och utjämningsvolym per meter som finns i arbetet för att komma fram till hur lång sträcka som rörmagasinet behöver anläggas på för att uppnå önskad utjämningsvolym. Poängsättningen som har gjorts för underhållet kan däremot återanvändas till andra fall. Begränsningar: Resultatet är tillämpbart i liknande typfall som för fallstudien, alltså vid radhus där ytan för utjämningsmagasinet är begränsat och där jordmånen har begränsade infiltrationsegenskaper. I arbetet har ett diagram tagits fram där anläggningskostnaden per meter framgår för respektive utjämningsmagasin och ett diagram med utjämnad volym dagvatten per meter. Dessa diagram kan därför tillämpas på andra fall med små ytor men med lite andra mått på tomten. Därav är resultatet även tillämpbart på andra fall. / Purpose: The problem with hard surfaces, as for example asphalt and roofing, is that they do not absorb enough rainwater. Furthermore, this leads to that grass surfaces and other absorbent surfaces around having to take care of all stormwater that the hardened surfaces cannot infiltrate. Flooding in urban environments has become increasingly common due to heavy rain and a high proportion of hard surfaces. This leads to an overload of the pipe line for rainwater. Therefore well-functioning balancing trays close to source needed to mimic natural drainage of nature. The goal was to investigate witch countervailing magazine mainly should be applied in heavily paved small terraced plots, where the soil has limited infiltration properties, in terms of efficiency, cost and maintenance. Method: The methods used to meet the objective is analysis of documents, qualitative interviews and a case study. The document analysis serves as a basis for the case study and interviews serve as empirical input for the case study. Findings: The countervailing magazine that is preferred is the pipe magazine when the plant surface is limited and the soil has limited infiltration properties. Implications: The problem statement treats the issue with an increasing number of floodings in urban environments due to the paved surfaces and the heavy rains. Furthermore, it is disclosed that the management system therefore risks becoming overloaded. This problem was also confirmed in the interviews. The work did not identify which countervailing magazine that is preferred for all kinds of cases, but only in the cases where land space is limited and where the soil has limited infiltration properties. The solution is therefore that pipe magazine is the magazine preferred for local disposal of stormwater in those circumstances. It is recommended when applying this result real life, to use the cost per meter and countervailing volume per meter available in efforts to work out how long stretch pipe magazine needs to be built on to achieve the desired equalization volume. Rating systems made for maintenance can however be used for other cases. Limitations: The result is applicable in similar scenarios as for the case study, which is at a row house site where the surface for the magazine is limited and where the soil has limited infiltration properties. A graph has been developed for the work where the construction cost per meter is described for each countervailing magazine and also has a graph with stormwater volume per meter been developed. These diagrams can therefore be applied to other cases with small areas but with other measures of the plot. Therefore the result also is applicable to other cases.
26

Novel Methods for Synthesis of High Quality Oligonucleotides

Semenyuk, Andrey January 2006 (has links)
<p>The first part of the work describes a procedure of oligonucleotide purification using a reversed-phase cartridge. The developed method employs a very efficient yet mild oligonucleotide detritylation on the cartridge support allowing fast purification of oligonucleotides regardless of their 5´-modification. Thiol- and amino-modified oligonuc-leotides were detritylated and purified with the same high efficiency as non-modified oligonucleotides. The method enables fast, parallel and automated purification of many oligonucleotide probes that was not possible before. In combination with the method of removal of tritylated failure fragments oligonucleotides were produced with purity superior to that of oligonucleotides purified using RP HPLC.</p><p>In the second part of the present study a method of solid-phase RNA synthesis using 2´-tert-butyldithiomethyl (2´-O-DTM) is discussed. The stability of the DTM group during oligonucleotide assembly and deprotection in ammonia, together with its ability for rapid deprotection under mild conditions, allowed the synthesis of RNA with the quality similar to that of synthetic DNA oligonucleotides. The advantage of the 2´-O-DTM group is that it is completely orthogonal to all protecting groups used for the traditional solid-phase DNA synthesis. Therefore, the synthesis can be performed using a standard DNA synthesis procedure – no changes are needed for the product assembly. RNA oligonucleotides synthesized with retained 5´-terminal trityl group can be subjected to a cartridge-based purification using the procedure described in the first part of the study. The phosphoramidite synthesis was optimized for a large scale preparation and gives versatility for introduction of other alkyldithiomethyl groups according to the preference to their certain properties.</p><p>The third part of the thesis describes the synthesis of a dithiomethyl linker and its utility for reversible conjugation of oligonucleotides. A dithiomethyl group, cleavable under mild conditions, was introduced onto 3´-OH of tritylated nucleosides via 3´-O-methylthiomethyl derivatives. The influence of different alkyl substituents on the disulfide bond stability was investigated, and stable analogues were employed in oligosyntheses. Two applications were developed using the present linker: 1) purification of oligonucleotides linked to the solid support; and 2) cartridge-based purification of tritylated oligonucleotides having an additional hydrophobic group on their 3´- terminus.</p>
27

Novel Methods for Synthesis of High Quality Oligonucleotides

Semenyuk, Andrey January 2006 (has links)
The first part of the work describes a procedure of oligonucleotide purification using a reversed-phase cartridge. The developed method employs a very efficient yet mild oligonucleotide detritylation on the cartridge support allowing fast purification of oligonucleotides regardless of their 5´-modification. Thiol- and amino-modified oligonuc-leotides were detritylated and purified with the same high efficiency as non-modified oligonucleotides. The method enables fast, parallel and automated purification of many oligonucleotide probes that was not possible before. In combination with the method of removal of tritylated failure fragments oligonucleotides were produced with purity superior to that of oligonucleotides purified using RP HPLC. In the second part of the present study a method of solid-phase RNA synthesis using 2´-tert-butyldithiomethyl (2´-O-DTM) is discussed. The stability of the DTM group during oligonucleotide assembly and deprotection in ammonia, together with its ability for rapid deprotection under mild conditions, allowed the synthesis of RNA with the quality similar to that of synthetic DNA oligonucleotides. The advantage of the 2´-O-DTM group is that it is completely orthogonal to all protecting groups used for the traditional solid-phase DNA synthesis. Therefore, the synthesis can be performed using a standard DNA synthesis procedure – no changes are needed for the product assembly. RNA oligonucleotides synthesized with retained 5´-terminal trityl group can be subjected to a cartridge-based purification using the procedure described in the first part of the study. The phosphoramidite synthesis was optimized for a large scale preparation and gives versatility for introduction of other alkyldithiomethyl groups according to the preference to their certain properties. The third part of the thesis describes the synthesis of a dithiomethyl linker and its utility for reversible conjugation of oligonucleotides. A dithiomethyl group, cleavable under mild conditions, was introduced onto 3´-OH of tritylated nucleosides via 3´-O-methylthiomethyl derivatives. The influence of different alkyl substituents on the disulfide bond stability was investigated, and stable analogues were employed in oligosyntheses. Two applications were developed using the present linker: 1) purification of oligonucleotides linked to the solid support; and 2) cartridge-based purification of tritylated oligonucleotides having an additional hydrophobic group on their 3´- terminus.
28

Modélisation du comportement des cartouches de protection respiratoire : exposition à des atmosphères complexes de vapeurs organiques et effet des cycles d’utilisation / Modelling of the behaviour of respiratory cartridge filter : exposure in complex atmosphere of organic vapours and effect of reuse cycles

Vuong, François 09 December 2016 (has links)
Les vapeurs de composés organiques volatils (COV) représentent un risque chimique pour les travailleurs. Les cartouches de protection respiratoires sont un moyen efficace contre les expositions à ces vapeurs. L’objectif de cette thèse est la modélisation de l’exposition des cartouches dans les situations complexes : présence d'un mélange de vapeurs et cycle d’utilisation, à partir d’une étude expérimentale basée sur l’adsorption dynamique sur colonne. Suite à la contribution de R. Chauveau (thèse UL – 24/11/2014) la présente thèse poursuit l’étude sur la modélisation de l’adsorption des mélanges de vapeurs. Des expositions à des mélanges de COV et une étude cinétique par la méthode chromatographique perturbative ont été effectuées. Le deuxième volet est consacré à la modélisation d’un cycle d’utilisation en 3 étapes (exposition - stockage – réutilisation), pour 6 COV : acétone, acétonitrile, 2-butanone, cyclohexane, dichlorométhane et éthanol. Les temps de claquage ont pu être prédits correctement pour les mélanges acétone/éthanol et cyclohexane/heptane. Une déviation est observée pour le mélange éthanol/cyclohexane car l’équilibre d’adsorption n’a pu être reproduit avec précision par les modèles et parce que la présence d’une covapeur influe grandement sur les cinétiques d’adsorption en mélange. Les travaux ont révélé des failles dans l’approche préventive consistant à assimiler une exposition de mélanges à une exposition à celle du composé le plus volatil en lui affectant la concentration totale du mélange. En ce qui concerne les risques liés à une réutilisation des cartouches, des percées immédiatement après réutilisation (IBUR) ont été observées expérimentalement. Ce comportement a pu être décrit par un modèle de diffusion statique. Le risque d’IBUR est élevé pour les COV diffusant rapidement : l’acétonitrile, l’acétone et le dichlorométhane. Une évaluation est proposée pour distinguer les propriétés du système qui influencent l’apparition de l’IBUR / Volatile organic compounds (VOC) represent a chemical risk for workers. Respiratory protective cartridges are effective equipment against vapours exposure. The objective of the present PhD thesis is the modelling of cartridge exposure in more complex situations: presence of vapours mixture and reuse cycle, from a dynamic adsorption experimental study in column bed. Further to the contribution of R. Chauveau (PhD thesis -24/11/2014), the present manuscript extends the study vapours mixtures adsorption on activated carbon. The second section is devoted to model a cycle use in 3 steps (exposure - storage – reuse), for 6 VOC: acetone, acetonitrile, 2-butanone, cyclohexane, dichloromethane and ethanol. VOC mixtures exposure and kinetic study by the method of perturbative chromatography have been carried out. The service life is correctly predicted for acetone/ethanol and cyclohexane/heptane mixtures. A deviation has been observed for ethanol/cyclohexane mixture because the adsorption equilibrium has not been accurately reproduced by model. These works have also pointed out inconsistency in the preventive approach which assimilates a mixture exposure to single vapour exposure by the most volatile compound at concentration the sum of that of all components of the mixture. Regarding the risks related to cartridge reuse, immediate breakthrough upon reuse (IBUR) has been experimentally recorded. This behaviour can be described by a static diffusion model. The mass transfer in the particle by surface diffusion is the main reason. The risk of IBUR is higher for fast diffusing VOC: acetonitrile, acetone and dichloromethane. An assessment is suggested in order to distinguish the properties of the system which can influence the occurrence of IBUR
29

Avalição toxicológica da linhagem bacteriana 358.1 isolada do petróleo sobre Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae). / Toxicologic evaluation of the 358.1 bacterium strain isolated from the oil on Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae).

GOMES, Jessé Malveira. 22 May 2018 (has links)
Submitted by Deyse Queiroz (deysequeirozz@hotmail.com) on 2018-05-22T15:00:44Z No. of bitstreams: 1 JESSÉ MALVEIRA GOMES - DISSERTAÇÃO PPGHT - 2017.pdf: 1522466 bytes, checksum: cc3a2a2cb3b9b312f031097d4500a8df (MD5) / Made available in DSpace on 2018-05-22T15:00:44Z (GMT). No. of bitstreams: 1 JESSÉ MALVEIRA GOMES - DISSERTAÇÃO PPGHT - 2017.pdf: 1522466 bytes, checksum: cc3a2a2cb3b9b312f031097d4500a8df (MD5) Previous issue date: 2017-03 / O milho é uma das culturas mais produzida e importante no mundo, sendo utilizada na alimentação humana e animal. O Brasil é um dos maiores produtores desse grão, sendo o terceiro maior produtor do mundo. Apesar de uma produção elevada, a produtividade é comprometida pela ação de insetos pragas, sendo a Spodoptera frugiperda Smith a de maior atuação nessa cultura. Em meio a esse desafio, o uso constante de inseticidas é utilizado com intuito de minimizar as perdas nas lavouras, porém, ocasionando grandes impactos ambientais, bem como a contaminação de trabalhadores rurais. Uma das estratégias viáveis e promissoras na supressão de pragas tem sido o manejo integrado de pragas (MIP), que tem como alicerce o uso isolado ou consorciado de técnicas de controles de pragas, sendo o controle biológico uma das ferramentas mais sustentáveis do ponto de vista ecológico. Desta forma, o presente trabalho teve como objetivo avaliar a toxicidade da cepa bacteriana 358.1 isolada do petróleo e o sobrenadante da cultura de células sobre o controle de lagartas de 2º e 3º instares de S. frugiperda, comparando as taxas de mortalidade e efeitos sobre seu desenvolvimento e com inseticidas químicos comerciais. O experimento consistiu de duas etapas, o primeiro ensaio foi realizado com lagartas de 3º instar com três diluições diferentes da cepa 358.1, sobrenadante da cultura de células, solução salina como controle negativo e o inseticida fenpropatrina como controle positivo. No segundo ensaio utilizou-se lagartas de 3º e 2º instares, a cultura celular da cepa 358.1 em sua concentração total (4 x 108 UFC/mL), seu sobrenadante da cultura, como controle negativo água destilada e testemunha positiva o produto comercial flubendiamida. Os experimentos com a cepa 358.1, sobrenadante da cultura de células e os produtos químicos testados não resultaram em uma taxa de mortalidade de S. frugiperda significante, porém, a cepa 358.1 e seu sobrenadante da cultura resultaram no aumento da duração da fase larval e em distúrbios morfofisiológicos do inseto, ocasionando, inclusive, no surgimento de adultos com asas atrofiadas, sendo desta maneira, promissores para à realização de novos testes. / Corn is one of the most produced and important crops in the world, utilized for human and animal feeding. Brazil is one of the top producers of this grain, being the third biggest producer worldwide. Despite the great production, the productivity is compromised due to the activity of insect pest. Because of this challenge, the continuous use of insecticides is done aiming to minimize lost in the crops. However, it causes major environmental impact and it is also contaminating rural workers. One of the viable and promising strategies to the pest suppression has been the pest integrated management (PIM), which is based on the use of isolated or consortium of pest controlling techniques, the biological control being one of the most sustainable tools in an ecological perspective. Therefore, the present study had the goal of evaluating the toxicity of the 358.1 bacterium strain isolated from the oil and supernatant of the cell culture under control of caterpillars from 2nd and 3rd instars of S. frugiperda, comparing the death rates and effects on their development, and also comparing with commercial chemical insecticides. The experiment consisted in two stages; the first assay was done with 3rd instar caterpillar with three different dilutions from the 358.1 strain, supernatant of the cell culture, saline solution as negative control, and fenpropatrina insecticide as positive control. On the second assay, 3rd and 2nd instars caterpillars were used, the cell culture from the 358.1 strain on its total concentration (4 x 108 UFC/mL), supernatant of the cell culture, distilled water as negative control and flubendiamida, a commercialized product, as the positive control. The experiments with the 358.1 strain, supernatant of the cell culture and the tested chemical products didn’t show a significant death rate for S. frugiperda, however, the 358.1 strain and supernatant of the cell culture resulted in an increase in the larval phase duration and on morphophysiological disturbs on the insect, resulting yet in the emergence of adults with atrophied wings, thus being promising to the realization of new tests.
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Návrh elektricky otápěného parního vyvíječe / Design of Electric Steam Heater

Pekárek, Michal January 2021 (has links)
This master’s thesis is focused on the design of electric steam generator for superheated steam. Using heating cartridge is the easiest way how to make a saturated or superheated steam. This device is part of gasification reactor, which is used for experimental purposes. The thesis includes schematic involvement of technology. Technology contains evaporator and superheater. The evaporator is calculated as pool boiling. The superheater is design for steam flowing through heating cartridge bundle. At the end of the thesis are made projection drawings, which are based on the calculations.

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