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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.
111

Development of a Machine to Control the Level of Washing in Panca Chili Seeds

De La Cruz, Anthony, Cardenas, Jaime, Vinces, Leonardo 01 January 2021 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / The washing of Panca chili seeds requires innovative solutions that allow controlling this process. It is necessary to handle variables (conductivity, pH, colorimetry) in the face of the challenge of working with small seeds. At present, there are no machines that are dedicated to the washing of this type of seeds, since in many companies this work is done manually, which is not the one indicated because this technique cannot guarantee homogeneity in the seed washing. In addition, direct handling of this type of seeds can cause irritation to the eyes and skin of the person who maintains contact with the seeds. That is why, it is proposed to make a machine to scale by means of a motorized rotary agitator inside a tank, in order to guarantee the homogeneity of the mixture when washing seeds. The present work will allow to determine, among two different types of agitators (axial and radial), which type of agitator is the most efficient in the washing of seeds of Panca chili, to achieve this objective the measurement of pH and electrical conductivity to the water will be carried after the mixture, after stirring. Finally, the analysis of the tests performed on the mixture obtained and washed by each type of agitator allowed to identify the turbine-type radial agitator, like the one that obtained greater efficiency in the washing of seeds, with respect to the helical agitator and pallets, designed for development of this work, in turn, could also confirm that this type of palette with the conductivity control allows to guarantee the homogeneity of the mixture during washing. © 2021, The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG. / Revisión por pares
112

Isolamento e identificação de substâncias provenientes da laranjeira ´Valência` (Citrus sinensis) envolvidas no estímulo e/ou quebra da dormência de estruturas quiescentes de Colletotrichum acutatum, agente causal da podridão floral dos citros / Isolation and identification of substances from sweet orange Valencia (Citrus sinensis) involved in the stimulation and/or dormancy-breaking of quiescent structures of Colletotrichum acutatum, causal agent of citrus postbloom fruit drop

Brand, Simone Cristiane 01 February 2012 (has links)
A podridão floral dos citros (PFC), causada por Colletotrichum acutatum, induz a abscisão de frutos jovens, podendo causar perdas de até 100%. A presença de inóculo viável na forma de conídios e/ou apressórios quiescentes na planta justifica a ocorrência generalizada da doença. Em períodos de chuva a PFC é agravada, possivelmente, em função de substâncias lavadas das diferentes partes da planta, as quais contêm metabólitos que estimulam o desenvolvimento do fungo. Diante do exposto, objetivou-se verificar o efeito das águas de lavagem brutas (ALBs) de flores, botões, folhas velhas (FV) e folhas novas (FN) e mistura destas sobre conídios, apressórios e hifas quiescentes de C. acutatum (isolados 61A e 142) in vitro e in vivo e sobre a severidade da PFC, bem como identificar substâncias presentes nas ALBs, exibindo a atividade biológica de interesse. Além disso, buscou-se verificar variações na composição das ALBs. O efeito de compostos voláteis brutos (CVBs) e os identificados a partir de laranjeira Valência (linalol, limoneno, mirceno, nonanal e a mistura destes) sobre o desenvolvimento do patógeno também foi avaliado. Todas as frações das ALBs estimularam a germinação dos conídios do fungo, sendo que a ALB de flores apresentou o maior estímulo para ambos os isolados. Para apressórios quiescentes (isolado 61A), o maior estímulo foi verificado nos tratamentos com ALBs de botões e da mistura e para conídios no tratamento mistura. Os maiores valores para comprimento do tubo germinativo foram observados nos tratamentos mistura, FN e botões. Para as estruturas quiescentes, o efeito das ALBs foi mais significativo para o isolado 142. Não foi observado efeito das ALBs sobre o micélio quiescente. Houve estímulo da germinação de conídios e ramificação de hifas in vivo, principalmente, em resposta ao tratamento com ALB de botões. A aplicação da ALB da mistura em flores resultou em maior severidade da PFC. Por sua vez, os CVBs apresentaram efeito inibitório. A exposição do isolado 61A aos voláteis (CVs) linalol, nonanal e mistura, resultou em germinação apenas na menor dose. O mirceno manteve a germinação semelhante a testemunha em todas as doses testadas, assim como limoneno nas doses de 0,005 a 0,25 µL mL-1. Todos os voláteis reduziram o comprimento do tubo germinativo. Para o isolado 142, houve redução em todas as variáveis para todas as doses dos CVs. Houve variações na composição das ALBs nas diferentes coletas, o que explica em parte a variação na capacidade de estímulo em alguns testes. Na ALB de flores, identificou-se a presença de cafeína, dos flavonóides glicosilados hesperidina e naringina, além de compostos glicosilados e peptídeos. Nas partes vegetais de laranjeira Valência foram identificados 54 CVs. As ALBs apresentam efeito estimulatório sobre conídios e apressórios quiescentes de C. acutatum in vitro e in vivo, bem como sobre a severidade da PFC. Os CVs linalol, limoneno, mirceno, nonanal e a mistura destes são, de forma geral, inibitórios ao desenvolvimento de C. acutatum. / The postbloom fruit drop of citrus (PFDC), caused by Colletotrichum acutatum, induces abscission of young fruits, and it may cause losses up to 100%. The presence of viable inoculum in the form of conidia and/or quiescent appressoria on the plant justifies the widespread occurrence of the disease. Under rain, the PFDC is increased, possibly due to substances washed from different parts of the plant, which contain metabolites that stimulate the development of the fungus. Therefore, we aimed to determine the effect of watery washing (WWs) of flowers, flower buds, old leaves (OL) and young leaves (YL) and the mixture of them on quiescent conidia and hyphae of C. acutatum (isolates 61A and 142) in vitro and in vivo and on the severity of the PFDC, and to identify substances in the WWs, exhibiting the biological activity of interest. In addition, variations in the composition of WWs were determinated. The effect of crude volatile compounds (CVCs) and those identified from Valencia sweet orange (linalool, limonene, myrcene, nonanal and the mixture of them) on the development of the pathogen was also evaluated. All fractions of WWs stimulated spore germination, and the flower WW exhibited the highest effect for both isolates. For quiescent appressoria (isolate 61A), the highest stimulus was observed in treatments with WWs from flower buds and the mixture and for quiescent conidia in the treatment mixture. The highest values for germ tube length were observed on the treatments mixture, YL and flower buds. For the quiescent structures, the effect of WWs was more significant for isolate 142. There was no effect of WWs on the quiescent mycelium. There was stimulation of conidia germination and hyphal branching in vivo in response mainly to treatment with WW from flower buds. The application of the mixture of WW in flowers resulted in higher severity of the PFDC. On the other hand, the CVCs showed inhibitory effect. Exposure of the isolate 61A to the volatiles (VCs) linalool, nonanal and the mixture of them, resulted in germination only at the lowest concentration. The germination on myrcene was similar to control at all doses tested as well as on limonene at doses from 0.005 to 0.25 mL mL-1. All volatiles reduced the length of the germ tube. In the case of isolate 142, a reduction in all variables for all concentration of VCs was observed. There were changes in the composition of WWs based upon times of harvesting, which partly explains the variations observed in the ability to stimulate the structures in some experiments. In flower WWs, we identified the presence of caffeine, the flavonol glycosides hesperidin and naringin, glycosylated compounds and peptides. In the plant parts of sweet orange \'Valencia\' were identified 54 VCs. The WWs have stimulatory effect on quiescent conidia and appressoria of C. acutatum in vitro and in vivo as well as in the severity of the PFDC. The VCs linalool, limonene, myrcene, nonanal and the mixture of them are, in general, inhibitory to the development of C. acutatum.
113

Extended Surfactants for Leather

Reetz, Ivo, Kilikli, A. 28 June 2019 (has links)
Content: Surfactants of different ionic nature are used in virtually all steps of leather production. In processes like soaking, degreasing and wool washing, tremendous amounts of surfactants are applied and to a great extent discharged into the tannery effluent. In order to improve the sustainability of leather processing, there is a constant search for more efficient, environmentally friendly emulsifiers, which give superior results already in smaller usage amounts. By introduction of propylene oxide based lipophilic linkers between the hydrophilic head and hydrophobic tail, the wetting and emulsion capability of a surfactant can be increased significantly. The resulting surfactants, so called extended surfactants, are generally more hydrophobic and have an extended tail, which reaches further into the oil face without scarifying the water solubility, what would be the results when increasing the alkyl chain. Thus, the use of lipophilic linker changes the emulsion on a structural level. Extended surfactants have been found to be superior in various applications, including textile laundry or tertiary oil recovery. In the present work, the efficiency of various types of non-ionic and anionic extended surfactants is demonstrated in various stages of leather making. Model surfactants with lipophilic linkers are compared to their analogues without linker molecules. In many processes, significantly improved surfactant efficiencies are found making this group of molecules an interesting topic for further exploitation. Take-Away: Significantly improved surfactant efficiency for more sustainable leather processing
114

Design kadeřnického křesla / Design of armchair for hairdressing

Nečasová, Barbora January 2008 (has links)
This thesis aims to design a modern innovative hairdresser chair. The main innovation of the proposal is seen in the new interior arrangement with a washing component as a central point. The main idea of the whole work is to design such a hairdresser chair that would supersede all other chairs normally used in hairdressing salons. All activities concerned with the hair care (washing, trimming, colouring etc.) would be done on a sole chair that would be in the case of need placed to the washing component. By reclining the chair backrest and turning the washing component a client’s hair could be easily washed (or other functions that need water tap could be done). There are several advantages within this proposal. Primarily it offers fewer chairs in hair dressing salon as well as a more variable interior. Another positive feature is that the washing component can be used more economically when it serves to more seats. Finally, the visual aspect and shape interconnection of two basic components - washing basin and hairdresser’s chair - are innovative.
115

Marti : A washing machine that grows with you

Sethi, Swasti January 2020 (has links)
A ubiquitous household appliance, the washing machine currently sees a fall in its usage life to a mere 7 years, with valuable and finite resources getting lost to the landfill faster than ever. The reason?  Mechanical obsolescence and barriers in repair that make helpless users as far removed from the process as possible. The goal of my degree project is to create long lasting product and service experiences through easier channels of repair and to design deeper partnerships between humans and the appliances that surround them. I want to be part of a rising sustainability movement that aims for a seismic shift in thinking by creating resilient product experiences.  Can the key to a sustainable future be appliances that last for generations?
116

Fem smutsiga små fingrar : En litteraturöversikt baserad påkvantitativ metod / Five Dirty Little Fingers : A literature overview based on quantitative method

Lagnerup, Isabella, Travell, Lisa January 2022 (has links)
Bakgrund: Vårdrelaterade infektioner är ett problem som tar upp resurser och vårdplatser. Ett av huvudproblemen är brister i handhygienen. Handhygienen ska utföras korrekt för att bedriva en god och säker vård. Det sistnämnda är en kärnkompetens hos den utbildade sjuksköterskor. Händerna utgör en smittväg mellan vårdpersonal och patienter. För att förhindra detta används skyddsutrustning men även handtvätt och handdesinfektion. Trots kunskap om handhygienens betydelse ses bristande tillämpning bland vårdpersonal.Syfte: Syftet är att identifiera faktorer som kan associeras med följsamheten till handhygien hos vårdpersonal inom somatisk slutenvård.Metod: I detta arbete har en litteraturstudie gjorts. Metoden som valts för att svara på syftet  är en kvantitativ metod. Observationsstudier (7) samt kombinerad observation och enkätstudier (3). Databaserna som användes var PubMed och Cinahl för att få fram relevanta artiklar.Resultat: Tio artiklar har sammanställts för att besvara syftet. Resultatet visade att handtvätt görs för sällan och ersätts med desinfektionsmedel. Arbetsbelastning och utbrändhet leder till sämre följsamhet till handhygien. Att handhygien spelar roll beroende av vilket typ av moment som ska genomföras. Följsamheten till handhygien var sämre innan kontakt med patientkontakt än efter. Slutsats: Dålig handhygien har setts på grund av olika faktorer, detta minskar patientsäkerheten genom risken för eventuell vårdrelaterade infektioner (VRI). Genom god handhygien minskar risken för smittbara ämnen vilket främjar både samhället och patienten. / Background: Healthcare related infections are a big problem in our society. This takes up unnecessary resources and hospital beds. One of the main problems is deficiencies in hand hygiene. Hand hygiene has to be performed correctly to provide good and safe care. Safe care is one of the nurses core competencies. Our hands transmit bacteria and viruses infections between the patient and healthcare professionals. To prevent this use protective equipment but also hand washing and hand disinfection. Aim: the purpose is to identify factors that can be associated with compliance with hand hygiene among care staff in somatic inpatient care.Method: In this work a literature study has been used. Observation studies (7) but also combined observation and questionnaire studies (3) was applied. Cinahl and PubMed were used as databases.Result: A total of ten articles were included in the result. The result showed that handwashing is not done as often as it should, and getting replaced with hand disinfection, workload and burnout leads to less compliance with hand hygiene. Hand hygiene plays a role depending on the type of procedures that are going to be performed. Adherens to hand hygiene were worse before patient contact than after. Conclusion: Poor hand hygiene has been due to various factors. This reduces patient safety through the risk of possible healthcare related infections (HRI). Good hand hygiene reduces the risk of infectious substances, which promotes both society and the patient.
117

Comparison of Transfer, Stability, and Persistence Between Touch and Bacterial DNA After Hand Washing and Sanitization

Martin, Kayla Ann 01 June 2022 (has links)
No description available.
118

Continuous Preventive Bridge Maintenance : Effect of High Pressure Washing on Concrete Bridges

Andersson, Louise January 2022 (has links)
In Sweden, as in many other countries, preventive maintenance of structures andbridges is considered important. It provides several benefits such as prolonged lifespan or service life, less need for repair, and hopefully reduced costs and lowerenvironmental impact. A large part of Sweden’s bridge stock is getting quite old. The idea that small actionscan improve and/or prolong the status of the bridge and postpone needs for repairor prevent damage with a reduction in life cycle cost is generally in the owner’sinterest. One such preventive maintenance measure is the annual washing ofbridges. While clear positive effects have been observed on the expansion joints,drainage system, and the bridge’s visual appearance, an important question is howthe washing affects chloride ingress, mainly from de-icing salts, in reinforcedconcrete bridge members. The hypothesis is that the high-pressure washing cleansaway the contaminants on the surface and in the long run reduces the chloridecontent. While the practical experience has been positive in Sweden, no research hasyet been done concerning the effect of high-pressure washing on chloride ingress inconcrete bridges. A study has been conducted on the preventive bridge maintenance practice of theSwedish Transport Administration (STA) and Swedish municipalities. This work hasbeen based on a literature review, a survey of municipalities’ bridge maintenance,and practical participation with contractors during annual maintenance. Field andlaboratory tests were carried out on the effect of washing on chloride ingress in twotypes of concrete. A field station was installed on an edge beam of a bridge and wasfollowed over three years’ exposure including winter seasons, winter maintenance,and annual washing in June. Also, an accelerated test method was developed in thelaboratory to simulate the yearly exposure and test the effect of high- pressurewashing in a long-term simulation over just a few weeks. The practical aspects of bridge maintenance seem to be quite similar betweenSweden and in other countries. However, in terms of descriptions of and availablemeans for maintenance and repairs, there seem to be larger differences. For the fieldstation, the results after one year’s exposure do not show anything more than theanticipated difference in chloride ingress between the two concrete types understudy. For year two, a slight difference indicated that washed samples had a reducedchloride content. For year three, however, there was no distinct difference betweenivwashed and unwashed samples. The reasons for this need to be further investigatedand examined. This will be done in the continuous tests of field exposure. The laboratory test method has been developed and successively improved. The shape and levels of chloride ingress are reasonable and comparable with fieldsamples. However, there is a need to examine the effect of natural rain exposurewhich might have the same or greater effect of diluting the chloride content aswashing the surface once a year. Other factors also need to be considered, such aswhen and how often the maintenance is performed. A first step to be able to examinethis has been completed through the development of the accelerated test method. / I Sverige, som i många andra länder, anses förebyggande underhåll avkonstruktioner och broar vara viktigt. Det har flera fördelar, som att förlängalivslängden eller bruksskedet, minska behovet av reparationer och förhoppningsvisminska kostnader och miljöpåverkan. En stor del av Sveriges brobestånd börjar bli relativt gammalt. Det gör attförebyggande underhåll får mer uppmärksamhet och ges större vikt. Idén att mindreåtgärder kan förbättra och/eller förlänga standarden på bron och förskjuta behovetav reparationer eller förebygga skador med en minskning i livscykelkostnader ärgenerellt i ägarens intresse. En typ av förebyggande underhåll är den årligatvättningen av broar. Tydliga positiva effekter kan ses på fogar, dränering samt bronsvisuella intryck men en viktig fråga är hur tvättningen påverkar kloridinträngning från huvudsakligen tösalter i armerad betong. Hypotesen är att högtryckstvätt tarbort föroreningar på ytan, vilket på lång sikt minskar kloridmängden i betongen. Den praktiska erfarenheten ska ha varit positiv i Sverige, men ingen forskning har utförtspå vilken effekt högtryckstvättning har på kloridinträngningen i en bro av betong. En studie om det förebyggande brounderhållet hos Trafikverket och kommuner harutförts med hjälp av Trafikverkets och föregångarna Vägverkets dokument, annanlitteratur, en enkät till kommuner samt medverkan och observationer av detpraktiska vid utförandeentreprenaders årliga utförande av underhållet. Fält- ochlaboratorieprover för undersökning av tvättningens effekt på kloridinträngningenhar utförts. En fältstation på en kantbalk på en bro har installerats och följts undertre års exponering, med vinterklimat, vinterunderhåll samt årlig tvättning i juni. Enaccelererad provningsmetod har utvecklats för att simulera den årliga exponeringenoch undersöka effekterna av högtryckstvättning i en långtidssimulering på baranågra veckor. Ur praktisk synvinkel verkar brounderhåll vara ganska likt i Sverige och andraländer. Dock verkar beskrivningar och tillgängliga ekonomiska medel för underhålloch reparation visa större skillnader, vilket kan ha en stor påverkan på broarnasskadestatus. För fältstationen, är resultatet efter ett års exponering inte speciellttydligt förutom den förväntade skillnaden mellan de två undersökta betongtyperna(en äldre och en modern, mer beständig kvalitet). För år två syns en mindre skillnadmellan tvättade och otvättade prover. Skillnaden kan inte observeras i resultaten förår tre dock. Orsaken till detta måste undersökas vidare. Detta görs genom dekontinuerliga provningarna som fortsätter. Den accelererade provningsmetoden har utvecklats och kontinuerligt förbättrats.Formen och nivån på kloridinträngningen kan anses rimliga och jämförbara (påformen) med fältprover. Dock finns det ett behov av att undersöka påverkan avnaturligt regn vilket kanske har samma eller större effekt på att späda utkloridmängden som att högtryckstvätta ytorna en gång per år. Andra aspekterbehöver också undersökas, till exempel när och hur ofta underhållet ska utföras. Ettförsta steg att möjliggöra det har avslutats med utvecklingen av den accelereradeprovningsmetoden. / <p>QC 20220509</p> / Förebyggande Brounderhåll
119

THE ROLE OF WATER PURITY IN EMULSIFICATION AND REMOVAL OF OIL FROM SOLID SURFACES

Tsompou, Andriani January 2021 (has links)
Detergents are broadly used in our everyday life for cleaning and washing procedures. They are however, a source of water pollution and can have a negative effect on human health and the environment. To reduce their negative impact, a new trend of using only pure water for washing and cleaning applications is being implemented. However, a scientific basis needs to be established first, as the mechanisms and the effectiveness of this method are not fully understood. In this work, we aim to investigate the effect of water purity on the removal of oil from surfaces and the stability of colloidal systems. To do that, two purified water grades are compared with non-purified tap water and 10 mM NaCl solution. Results from measurement of oil film mass before and after water contact and Quartz Crystal Microbalance with Dissipation (QCM-D) indicate that purified water grades can wash a surface more efficiently than non-purified water grades. Contact angle measurements show that pure water facilitates the cleaning process while spreading of oil on plastic surfaces indicates that electrostatic interactions have an important role in the system. Visual observations of o/w emulsions, show that purified water grades redisperse the oil better. We hypothesize that the mechanism behind the cleaning and washing without detergents relies on the electrostatic interactions. To further investigate the effect of salt on cleaning mechanisms, we performed zeta potential measurements. Results indicate that salt has a negative effect on the stability of the particles.
120

ColorsxStudios och skatten vid regnbågens slut : Den mytiska marknadsföringen och det autentiska ansvaret

Fox, Moa January 2021 (has links)
I dagens läge vill konsumenter se varumärken ta ställning i politiska och sociala diskurser och därför tenderar varumärken ofta navigera för att kunna representera sig själva som brydda om olika aktuella politiska frågor. När man ser till hur varumärken försöker ligga i linje med idéer om social rättvisa är det viktigt att notera kapitalismens roll i samhället, där det som är moraliskt ofta är bestämt eller påverkat av det som har ekonomiskt värde. Den här uppsatsen ämnar undersöka musikplattformen ColorsxStudios underliggande politiska budskap med hjälp av Roland Barthes teori om Myten. Uppsatsen dsikuterar även huruvida marknadsföringen plattformen bedriver är etiskt hållbar och förenlig med deras underliggande budskap och ideologi. Detta görs med hjälp av begreppet woke washing.

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