The presented study deals with the sol-gel synthesis of nanocrystalline ternary phases of the general formula ZnxTiyOz, their characterization and potential application in photonics. Achieved results brings new fundamental knowledge about the processes leading to the formation of ZnxTiyOz nanocrystals from amorphous xerogels and gives novel information about structural and opto-electrical properties of prepared materials. Based on the presented results, most of all up-to-date reported ZnxTiyOz compounds with tailored nanocrystalline size and structure can be prepared as powders or thin films. Two sol-gel approaches based on the cluster process and direct heteronucleation were employed to prepare initial sol. Sols were optionally doped by Eu3+ ions to evaluate the effects of rare earth element to crystallization properties of formed compounds. In the first part of our study crystallization properties and structural evolution of thermally treated xerogels were analyzed. As a result a versatile method allowing the preparation of inverse spinel Zn2TiO4, cubic defect spinel ZnTiO3 and rhombohedral ZnTiO3 with tailored nanocrystal sizes was established. Initial composition and thermal annealing allow us to prepare selected ternary phase with tailored nanocrystal size ranging from tens of nanometers up to...

Fibers are classified into two groups; natural fibers and man-made fibers (MMF). There are three kinds of MMF: those made by transformation of natural polymers, those made from synthetic polymers and those made from inorganic material. Chitosan is classified as a biobased polymer and can be spun into man-made fibers. Due to its various functions, including anti-microbial, biocompatibility, biodegradability, metal-chelating, metal ions-coupling properties and general high molecular affinity, much attention has been paid recently to include chitosan into various concepts. The overall aim of this master thesis was to investigate the possibilities to make an antibacterial paper. Because chitosan contain primary amino groups that are cationic under mildly acidic conditions, it has antibacterial properties. Lab scale spinning of chitosan filaments was attempted in order to produce chitosan staple fibers that could be mixed with pulp fibers to make paper with antibacterial properties. Spinning methods used for a particular polymer is determined by the characteristics of the polymer. In the development of chitosan spinning at laboratory scale three different spinning methods were tested. A successful filament was produced by dry wet spinning. The filament was superior to the others in terms of dope composition and weight ratio of chitosan/acetic acid for protonation of the amino groups. Furthermore, the addition of glycerol improved the swelling of the chitosan hydrogel (or dope). Moreover, the condition of the coagulation step resulted in a good solidified filament with satisfactory elasticity and strength to be able to be taken up by a drawing cylinder. However, too small amounts of chitosan were produced in the development of chitosan spinning at lab scale and for production of antibacterial paper of chitosan. A second option was melt spinning of polylactide (PLA) filaments containing various amounts of chitosan. In this case PLA act as a carrier of chitosan into the paper sheet. Continuous filaments were spun in a sufficient amount. The antibacterial activity of PLA/chitosan fibers on E. coli bacteria was tested both on PLA/chitosan fibers as well as on suspensions. Under nutrient free conditions weak antibacterial effects was observed both for fibers and suspensions. However, in a more nutrient rich environment no effect was observed. This suggests that the produced fibers only had a weak antibacterial activity. To my knowledge the use of PLA in fiber form to carry chitosan into paper has not been attempted previously although different approaches to use chitosan as e.g. wound dressing is well described. In conclusion, there is a possibility to produce man made biodegradable fibers using chitosan and PLA that potentially could be added to paper. This paper might exert antibacterial properties that could have an interest to the market, e.g. for cleaning, in hospitals, and in the food industry.

Adobe is a building material that has been used since ancient times, but is not as widely used as clay bricks or concrete for housing construction. In addition, it uses a construction technique that has been passed down and improved from generation to generation. In view of this, the present work aims to improve the properties of adobe by using PET bottle fibers in its composition. A mechanical test and two physical tests were carried out for adobe with 0% (standard adobe), 2%, 4% and 6% PET fibers, where it was observed that the adobe with 6% PET fibers obtained the best results, since it increased the compressive strength of the adobe by 19%, reduced the absorption percentage by 12% and finally reduced the density by 16.4%. Therefore, the addition of PET fibers in adobe is recommended, as it contributes to improve its mechanical and physical properties. Additionally, it reduces pollution in streets, rivers, parks, etc. because it promotes the recycling of PET bottles.

Este estudio tiene como objetivo conocer la aplicación del concepto de sostenibilidad en la marca Galera de Lima entre los años 2017 – 2020. Para poder solventar este objetivo, primero se definirá el concepto de sostenibilidad en la moda; en segundo lugar, se describirá la marca Galera tomando en cuenta su visión, misión y objetivos; y, por último, se detallará la aplicación del concepto de sostenibilidad a la marca, es decir, se explicará cómo la marca incentiva la sostenibilidad ambiental, el proceso de producción, el material que se utiliza, así como también, las iniciativas de responsabilidad social que tienen como empresa. Se tomó como caso de estudio a Galera, marca limeña de moda sostenible que trabaja los accesorios con fibra vegetal (toquilla, mimbre y junco) tejida por los artesanos peruanos, porque es una empresa sostenible con un enfoque de responsabilidad social adecuado y porque la información sobre su funcionamiento era accesible. Finalmente, la interrogante de investigación se responderá mediante el uso de metodología cualitativa etnográfica con fuentes bibliográficas pertinentes y por medio de entrevistas a la dueña de la marca y trabajadores que manejan información de lo requerido. / This study aims to learn about the application of the sustainability concept in the brand Galera from Lima, between the years 2017 - 2020. In order to solve this objective, the concept of sustainability in fashion will first be defined; secondly, the Galera brand will be described by mentioning vision, mission and objectives; and finally, the application of the sustainability concept in the brand will be detailed. To do this it will be explained how the brand encourages environmental sustainability, production process, materials used, as well as the social responsibility initiatives that they have as a company. Galera was taken as a case study, it is a Lima brand of sustainable fashion that works with accessories made of vegetable fibbers (toquilla, wicker and reed) woven by Peruvian artisans. It was chosen because it is a sustainable company and its adequate social responsibility, also the approach and the information about its operation was accessible so it made it easier to obtain information. Finally, the research question will be answered through the use of a qualitative ethnographic methodology with pertinent bibliographic sources and through interviews to the owner of the brand and workers who handle information as required.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第19570号 / 医博第4077号 / 新制||医||1013(附属図書館) / 32606 / 京都大学大学院医学研究科医学専攻 / (主査)教授 松田 秀一, 教授 開 祐司, 教授 妻木 範行 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

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After a major flooding disaster, construction materials will be scarce during early recovery stages and any material of reasonable quality would be useful. Instead of importing higher quality material from sites a considerable distance away, on-site material may be useable. This thesis explores usage of specialty portland cements, and in some cases polymer fibers, as stabilization additives to fine grained soils with elevated moisture contents. The primary objective of this thesis is to develop strength, modulus, and ductility trends for a variety of soil types, cementitious materials, cementitious material contents, and moisture contents, and to use the data to compare specialty grind portland cements to commercially available portland cement from the same production facility. The secondary objective is to evaluate the effect of polymer fibers combined with portland cement for the same mixtures. Over 1300 Unconfined Compression (UC) tests were conducted to complete these two objectives.

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