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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.
1

Marketing channels of synthetic rubber in Taiwan and China

Chen, Cheng-teh 14 July 2010 (has links)
In Taiwan, the rubber industry began to bloom from the Japanese Colonial Era, and most of the rubber technologies were originated from Japan. Its evolution began from the rubber parts to the synthetic rubber manufacturing. The most of synthetic rubber manufacturers are cooperated with companies from Japan and US, the rubber industry was allowed to develop vigorously in a short period of time. In contrary to Taiwan, China could only obtain the obsolete rubber technologies and management skills from the Former USSR due to economy sanction during the Cold War period. The rubber industries lagged behind in terms of quality, production efficiency, and management. As China embraced the Socialist Planned Economy after the Communist Victory in Civil War, the marketing and sales made subject to state control and development was being dragged. After the Reform and Opening-Up, although there were a bunch of rubber manufacturers from Japan and western countries started to establish local production activities in China, the foreign investment bogged down after the Tiananman Square Protest in 1989. Only the Taiwanese manufacturers moved their steps to China against the tide with modern production technologies and management skills. The complementary development brought by Taiwan and China contributed significant improvement in quality of Chinese rubber goods and became a story on everybody¡¦s lips on the cooperation of the rubber industries between two sides of Taiwan Strait. Rubber industries are closely related to national defense and consumer goods, which makes themselves equally import to plastic industries. However, due to the labor-intensive nature of rubber industries and the serious lack of labor force in Taiwan in 1990¡¦s, the Taiwanese rubber industries began to move their production sites to China and accelerated the inosculation of the rubber industries in Taiwan and China. As the main raw material of rubber industries, the synthetic rubber is no exceptional either. In the end of 20th Century, China has successfully become the ¡§World Factory¡¨ and the consumption and capacity of synthetic rubber became the top of the world. Then the financial crisis in 2008 turned the China¡¦s policies to concentrate the development of the domestic demand, which made China the ¡§World Market¡¨. In recent years, the relationships between Taiwan and China have been substantially improved. The Economy Cooperation Framework Agreement (ECFA) is officially signed and taking effects, the economical activities and relationships between both sides are expected to be more liberalized than the past. The study is specially focused on the evolution of the marketing channel of the synthetic rubber between Taiwan and China, and how ECFA is going to possibly affect the synthetic rubber industries. The study will integrate the writer¡¦s points of view and the various ideas abstracted from the interviews with the several Associations and main agents/distributors in Taiwan and China in order to infer the trends of future development of rubber industries. With this study, the readers who are in the business are allowed to be more clear about the evolution of the marketing channel of the synthetic rubber industries and the trends of future development, so that the readers can take the initiatives to prepare for the future.
2

Gummistövel : En materialvalstudie för gummistövlar ur ett miljöperspektiv

Franzén, Rebecca, Torstensson, Johanna January 2020 (has links)
Gummistövlar är en väsentlig del av många människors liv och utgör idag en viktig del av företaget Polarn O. Pyrets produktsortiment. Gummistövlar tillverkas av flera olika material såsom naturgummi (NR), styren-butadien-gummi (SBR), termoplastiska elastomerer (TPE) samt termoplaster. Syftet med rapporten är att, genom en materialjämförelse, reda ut hur en gummistövels miljöpåverkan ser ut. Genom en litteraturstudie har en jämförelse av råvaruutvinning och tillverkningsprocess utförts samt en översikt kring hur de olika materialen omhändertages vid livets slut. En gummistövel med en lång livslängd har i regel en lägre miljöpåverkan än en stövel med en kort livslängd. I och med en avsaknad av livscykelanalyser (LCA) för specifikt gummistövlar har detta emellertid försvårat och påverkat utformningen av arbetet. Sammanfattningsvis visade studien att råvaruutvinning av både NR samt syntetiskt gummi såsom SBR, TPE och termoplaster är samtliga material som har en negativ påverkan på den biologiska mångfalden i flera anseenden. Vad det gäller tillverkning av TPE och termoplaster har dessa material en lägre energiförbrukning och färre resurssteg vilket i sin tur genererar en lägre miljöpåverkan. Det är dessutom möjligt att återvinna dessa typer av material till skillnad från vulkat gummi såsom NR och SBR. Återvinningsmöjligheten är emellertid begränsad i och med en bristfällig infrastruktur för återvinning inom kläd- samt skoindustrin i allmänhet. / Rubber boots are an essential part of many people’s lives and today form an important part of the company Polarn O. Pyret’s product range. Rubber boots are made of several different materials such as natural rubber (NR), styrene-butadiene rubber (SBR), thermoplastic elastomers (TPE) and thermoplastics. The purpose of the report is to, through a material comparison, find out what the environmental impact of a rubber boot looks like. Through a literature study, a comparison of raw material extraction and a manufacturing process was made as well as an overview of how the various materials are handled at the end of life. A rubber boot with a long service life usually has a lower environmental impact than a boot with a short service life. However, due to the lack of life cycle analysis(LCA) for specific rubber boots, this has made it difficult and affected the design of the work. In summary, the study showed that raw material extraction of both NR and synthetic rubber such as SBR, TPE and thermoplastics are all materials that have a negative impact on biodiversity in several respects. As regards the production of TPE and thermoplastics, these materials have a lower energy consumption and fewer resource steps, which in turn generate a lower environmental impact. It is also possible to recycle these types of materials unlike vulcanized rubber such as NRand SBR. However, the possibility of recycling is limited due to a poor infrastructure for recycling in the clothing and shoe industry in general.
3

Avaliação do potencial de transformação de compostos tóxicos por isolados de Gordonia paraffinivorans e Gordonia sihwensis provenientes de compostagem / Evaluation of the potential for transformation of toxic compounds by Gordonia paraffinivorans and Gordonia sihwensis isolated from composting

Braga, Stefania Pegorin 08 June 2018 (has links)
A biorremediação é uma metodologia eficiente na recuperação de ambientes poluídos. Ela emprega organismos capazes de degradar compostos tóxicos transformando-os em substâncias menos agressoras. Dentre os microrganismos que são utilizados para este fim, o gênero Gordonia tem se destacado bastante devido a sua grande versatilidade metabólica, o que permite a utilização de substratos complexos e tóxicos como fonte energética, eliminando-os do meio ambiente. O sequenciamento e a análise dos genomas de dois isolados de G. paraffinivorans (MTZ041 e 052) e de um isolado de G. sihwensis (MTZ096), provenientes da compostagem, demonstrou que esses microrganismos possuem os elementos genéticos que conferem a habilidade de degradar hidrocarbonetos, borracha sintética e borracha natural. Para comprovar a capacidade desses isolados em utilizar estas diferentes fontes de carbono, foram realizados ensaios contendo um indicador de óxido redução (2,6 DCPIP), cinéticas de crescimento, análises químicas (Cromatografia Gasosa, CG), qPCR e microscopia eletrônica de varredura (MEV). Os três isolados usados neste trabalho foram capazes de utilizar hidrocarbonetos como fonte única de carbono. Os resultados dos ensaios cromatográficos demonstram que G. paraffinivorans MTZ041 consumiu 28,92% do hexadecano presente no meio, contra 69,80% consumido por G. sihwensis MTZ096 ao longo de 168 horas. As curvas de crescimento também demonstraram que a biomassa acumulada por G. sihwensis MTZ096 é 3,3 vezes maior do que a biomassa de G. paraffinivorans MTZ041 para o tratamento com hexadecano, totalizando 3,68 mg/ml e 1,11 mg/ml, respectivamente. Conforme esperado, mediante estas observações, a presença de hexadecano como fonte única de carbono no meio de cultivo, levou ao aumento da expressão dos genes responsáveis pela degradação de hidrocarbonetos. Para o sistema CYP 153, os genes FER, CYP 153 e FER RED tiveram sua expressão aumentada 750, 232 e 110 vezes, respectivamente. Já os genes alk B, rub A3, rub A4, rub B e alk U do sistema alcano hidroxilase tiveram sua expressão aumentada em 248, 1576, 1296, 6,6 e 20 vezes respectivamente. Estes resultados confirmam dados prévios da literatura de que os isolados de Gordonia tem grande potencial para biotransformação de hidrocarbonetos. Em relação à capacidade de assimilação de borracha sintética e natural, as análises in silico demonstraram que somente os isolados da espécie G. paraffinivorans possuem o gene Lcp (Látex Clearing Protein) responsável pelo primeiro passo da assimilação destes substratos. As curvas de crescimento em borracha natural e sintética como fonte única de carbono foram realizadas ao longo de 11 semanas e demonstram a capacidade destes substratos em suportar o crescimento robusto. Durante 80 dias, foi possível evidenciar a presença de bacilos e a formação de biofilme na borracha sintética e natural por meio de MEV. Este é o primeiro relato na literatura de G. paraffinivorans assimiladora de borracha e a terceira espécie do gênero Gordonia com esta habilidade metabólica. Dada a grande complexidade deste substrato e a escassez de microrganismos com esta capacidade, a descrição e a caracterização deste isolado são de grande originalidade e relevância biotecnológica. / Bioremediation is an efficient methodology on recovery of polluted environments. It acts employing microorganisms capable of degrading toxic compounds into less aggressive substances. Among the microorganisms used in bioremediation, the genus Gordonia has stood out due to its great metabolic versatility, which allows the use of complex toxic substrates as energy source, eliminating them from the environment. Sequencing and analysis of the genomes of two isolates of G. paraffinivorans (MTZ041 and 052) and an isolate of G. sihwensis (MTZ096) from composting, demonstrated that these microorganisms possess the genetic factors that confer the ability to degrade hydrocarbons, synthetic and natural rubber. To prove the capacity of growth of the isolates in these carbon sources, growth tests were carried out containing an oxide reduction indicator (2,6 DCPIP), kinetics growth, chemical analysis (gas chromatography, CG), qPCR and scanning electron microscopy (SEM). The three isolates used in this study were able to utilize hydrocarbons as sole carbon source. The results of the chromatographic assays show that G. paraffinivorans MTZ041 consumed 28.92% of the hexadecane present in the medium, against 69.80% consumed by G. sihwensis MTZ096 over 168 hours. The growth curves also showed that the biomass accumulated by G. sihwensis MTZ096 is 3.3 times higher than the biomass of G. paraffinivorans MTZ041 for the hexadecane treatment, resulting in 3.68 mg/ml and 1.11 mg/ml, respectively. As expected by these observations, the presence of hexadecane as carbon source in the medium led to an increased expression of the genes responsible for the degradation of hydrocarbons. For the CYP 153 System, genes FER, CYP 153 and FER RED had an increased expression of 750, 232 e 110 times, respectively. As for the Alkane Hydroxylase System, genes alk B, rub A3, rub A4, rub B and alk U had an increased expression of 248, 1576, 1296, 6,6 e 20 times, respectively. These results confirm previous data from the literature that Gordonia isolates have a great potential for biotransformation of hydrocarbons. Regarding assimilation of synthetic rubber and natural, in silico analysis demonstrated that only the isolates from the species G. paraffinivorans have the Lcp gene (latex Clearing Protein) responsible for the first step of the assimilation of these substrates. The growth curves in natural and synthetic rubber as carbon source were conducted over 11 weeks and demonstrate the ability of these substrates to support the robust growth of G. paraffinivorans . During 80 days, it was possible to evidence the presence of bacilli and the formation of biofilms on natural and synthetic rubber by SEM. This is the first report in the literature of G. paraffinivorans as a rubber degrader and the third species of the genus Gordonia with this ability. Given the complexity of this substrate and the shortage of micro-organisms with this capacity the description and characterization of this isolate is of great originality and biotechnological relevance.

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