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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.
491

Proyecto Kit de Cuidado Dental Biodent / Project kit biodent

Albujar Sanchez, Raquel Irene, Cuadros Vargas, Ana Lucía, Cruz Gavidia, Octavio Klaus, Díaz Zamora, Manuel Augusto, La Madrid Mercado, Mauricio 03 March 2021 (has links)
BioDent se crea a partir de la falta de productos eco amigables en la industria de cuidado bucal, ofreciendo una alternativa natural y orgánica que garantiza la efectividad de una pasta dental convencional ya que posee flúor y carboncillo, componentes que cuidan el esmalte y estructura de los dientes además de prevenir caries. Al ser una empresa que vela por la sostenibilidad medioambiental, Biodent utiliza envases y materiales biodegradables en sus productos como vidrio y bambú. Así mismo, se crea la iniciativa de inculcar a los futuros clientes el amor por la naturaleza y el ambiente que los rodea a través de la incorporación de una semilla de menta de crecimiento rápido en el cepillo de bambú que podrá ser plantada cuando se desee. Es necesario que la sociedad peruana tome conciencia sobre la gran cantidad de plástico que consume día a día en la mayoría de los productos que utiliza, incluyendo los de belleza y cuidado personal ya que a partir de ello se podrá lograr un verdadero cambio en donde la sostenibilidad ambiental este por encima de todo. / BioDent was created due to the lack of eco-friendly products in the oral care industry, offering a natural and organic alternative that guarantees the effectiveness of a conventional toothpaste, since it has fluoride and charcoal, components that take care of the enamel and structure of the teeth, in addition to preventing cavities. As a company that cares for environmental sustainability, Biodent uses biodegradable packaging and materials in its products, such as glass and bamboo. Likewise, the initiative is created to instill in future customers the love for nature and the environment that surrounds them through the incorporation of a fast-growing mint seed in the bamboo toothbrush that can be planted whenever desired. It is necessary that Peruvian society becomes aware of the large amount of plastic consumed every day in most of the products they use, including beauty and personal care products, since this will help to achieve a real change where environmental sustainability is above all. / Trabajo de investigación
492

Importance of Molecular interactions to Design Non-ionic Coacervates for Drug Delivery Applications

Kundu, Mangaldeep January 2021 (has links)
No description available.
493

Doprinos analize tokova fosfora razvoju ciljno orijentisanog upravljanja biorazgradivim otpadom / Contribution of phosphorus flow analysis for development of goal-oriented biodegradable waste management

Vujović Svjetlana 13 October 2020 (has links)
<p>Cilj ove disertacije je razvoj modela zasnovanog na analizi tokova<br />materijala (MFA) i analizi tokova supstanci (SFA) sistema<br />upravljanja biorazgradivim otpadom sa naglaskom na upravljanje<br />fosforom kao resursom. U zemljama u tranziciji kao što je Srbija<br />upravljanje biorazgradivim otpadom predstavlja poseban problem jer<br />se dovodi u direktnu vezu sa emisijama gasova sa efektom staklene<br />bašte i generisanjem procednih voda. Kako bi se razvila strategija<br />upravljanja biorazgradivim otpadom u skladu sa zahtevima EU<br />direktiva, razvijeni model je primenjen na sistem upravljanja<br />biorazgradivim otpadom u Srbiji, i dva alternativna scenarija. Na<br />osnovu rezultata primenjenog modela, sva tri razvijena scenarija<br />upravljanja biorazgradivim otpadom su evaluirana i izvršeno je<br />njihovo poređenje.</p> / <p>The aim of this dissertation is biodegradable waste management system model development based on material flow analysis (MFA) and substance flow analysis (SFA) with an emphasis on phosphorus management as a resource. In transition countries like Serbia, biodegradable waste management is a particular problem due to direct linkage with greenhouse gas emissions and leachate generation. In order to develop a biodegradable waste management strategy in accordance with the requirements of EU directives, developed model was applied to the biodegradable waste management system in Serbia, and two alternative scenarios. Based on the results of the applied model, evaluation and comparison of all three developed scenarios of biodegradable waste management is performed.</p>
494

Višeskalna strategija strukturiranja polimernih nano-kompozita na osnovu različitih prekursora / Multiscale strategy of structuring polymer nano-composites based on various precursors

Tanasić Ljiljana 22 July 2011 (has links)
<p>Ovaj rad je imao za cilj , razvoj postupka sinteze polimernih prekursora mreža na bazi<br />obnovljivih sirovina. Razvijen je postupak sinteze poli laktida u rastvoru dihlor metana. Vreme trajanja postupka sinteze je 6 h, a uspe&scaron;nost samog procesa je potvrđena metodama identifikacije i karakterizacije dobijenih polimera PLLA. U ovom radu, za ispitivanja dobijenih polimernih materijala, uzimajući u obzir ideju o krajnjoj nameni, kori&scaron;ćene su sledeće metode: GPC ( Gel Permeation Chromarography) za određivanje raspodele molekulske mase; IR spektrofotometrija, prikazuje vibraciju atomskih, molekulskih ili funkcionaknih grupa; i termička analiza TGA i DSC, za praćenje promena pri kontrolisanom zagrevanju i hlađenju.<br />Jedan od ciljeva rada je bio i da se da pregled postojećih teorija ojačanja elastomera punilima sa nano česticama, i ispita pona&scaron;anje nano-kompozitnih materiajala pod dejstvom visoko energetskog zračenja ( gama zračenja). U eksperimentalnom delu ispitivani su elastomerni materijale na bazi butadienakrilonitrilnog kaučuka (NBR) i hlorsulfonovanog polietilenskog kaučuka (CSM) . Me&scaron;anjem CSM i NBR formiraju se umreženi sistemi, koji se koriste kao prekursori mreža za dobijanje nano-kompozitnih materijala ojačanaih česticama aktivnih punilačađi i silicijum (IV) oksida. Kod tako dobijenih materijala ispitivane su karakteristike pre i posle ozračivanja &gamma; zracima. Dinamičko-mehaničkom analizom potvrđen je ojačavajući efekat punila.</p> / <p> This work was aimed at the development procedure for the synthesis of polymer precursors<br /> network based on renewable raw materials. Developed a procedure for synthesis of poly<br /> lactide in solution, dichloro methane. The duration of the synthesis procedure was 6 h, and<br /> the success of the process was confirmed by the methods of identification and<br /> characterization of the obtained polymer PLLA. In this paper, the investigation obtained<br /> polymer materials, taking into account the idea of final destination, following methods were<br /> used: GPC (gel permeation Chromarography) to determine the distribution of molecular<br /> weight, IR spectrophotometry, showing the vibration of atomic, molecular or funkcionaknih<br /> group, and thermal analysis TGA and DSC, to track changes in a controlled heating and<br /> cooling.<br /> One of the aims of this study was to be given to review of existing theories of reinforcement<br /> fillers elastomer with nano particles, and examine the behavior of nano-composite<br /> materiajala under the influence of high energy radiation (gamma radiation). In the<br /> experimental part of elastomeric materials have been studied on the basis of<br /> butadienakrilonitrilnog rubber (NBR) and chlorosulphonated polyethylene rubber (CSM). CSM NBR mixing and forming the network system, which are used as precursors for a<br /> network of nano-composite particles ojačanaih active fillers-carbon black and silicon (IV)<br /> oxide. With so obtained materials were investigated characteristics before and after<br /> irradiation with &gamma; rays. Dynamic-mechanical analysis confirmed the reinforcing effect of<br /> fillers.</p>
495

Utilisation du caséinate de sodium pour la fabrication de films actifs pour l’emballage alimentaire : étude des propriétés barrières aux gaz, de l’activité antimicrobienne et de la biodégradabilité / Fabrication of sodium caseinate edible films for active food packaging : study of gas barrier properties, antimicrobial activity and biodegradability

Colak, Basak Yilin 14 November 2014 (has links)
La mondialisation des marchés, les changements d’habitudes de consommation et les préoccupations croissantes concernant la sécurité alimentaire et l’environnement sont des éléments moteurs pour le développement des films d’emballage comestibles/biodégradables antimicrobiens. Une utilisation en masse de ce type de film est dépendante principalement des verrous technologiques car le mode de fabrication actuellement utilisé pour ce genre de film consiste à utiliser un procédé (voie solvant) qui n’est pas toujours adapté à une production importante et continue. L’étude présentée ici permet de montrer la possibilité d’obtenir des films comestibles antimicrobiens à partir de caséinate de sodium en utilisant les procédés traditionnels de la plasturgie : extrusion bi-vis et extrusion-gonflage. Grâce aux optimisations des paramètres d’élaboration tels que la température de transformation, le taux de cisaillement et le taux de plastifiant, les matériaux contenant un agent actif naturel : le lysozyme, la nisine ou la natamycine ont gardé en partie leurs activités antimicrobiennes. Par des caractérisations mécaniques et physico-chimiques des films thermoplastiques, il a été démontré que ces films ont des propriétés mécaniques et barrières similaires à ceux fabriqués par voie solvant. Ces propriétés dépendent principalement du taux de plastifiant. Ainsi, il est possible de fabriquer des films comestibles antimicrobiens de caséinate de sodium avec de bonnes propriétés mécaniques et barrières qui ne sont pas affectées par la transformation thermomécanique et qui peuvent être adaptées en fonctions des applications en variant le taux de plastifiant / Because food market becomes international, consumers are changing their habits and they are more concerned about food security and environmental issues, there are driving forces for the development of edible/biodegradable antimicrobial packaging films. However, fabrication process (solution-casting) of these kinds of films isn’t always suitable for a continuous industrial big production. The present study demonstrates the suitability of sodium caseinate based edible antimicrobial films to be fabricated by some conventional plastic transformation processes: twinscrew extrusion and blown-film extrusion. Thanks to the optimizations of elaboration parameters such as extrusion temperature, shear and plasticizer ratio, the materials incorporated with one of the following active agents: lysozyme, nisin or natamycin, partially kept their antimicrobial activity. Physical-chemical film characterization of films emphasized that the type of transformation process doesn’t have any influence on tensile or gas barrier properties. These properties are mainly affected by plasticizer type and content. Thus, sodium caseinate based edible antimicrobial films can be produced successfully by thermo-mechanical processes without losing good mechanical and gas barrier properties
496

Bioodpad: školní projekt pro 2. stupeň základní školy / Biodegradable Waste: School Project for Lower Secondary School

Dvořáková, Kateřina January 2021 (has links)
The proper way to manage biological waste has only recently become a topic of discussion and the public still does not have enough information about it and does not have a comprehensive opinion. In order for bio-waste to be properly managed, knowledge of this topic and positive attitude towards it is necessary, in class this could be achieved by activating pupils through project based education. Teaching in projects is a great way to understand the issue, which can influence pupils' attitudes towards bio-waste management. The aim of this diploma thesis is to create a project on the topic of biodegradable waste, and then to find out how the knowledge and opinions of students about bio-waste have changed. The created project was verified at the lower secondary school, for which it is primarily intended. A total of 54 6th-year pupils was involved in this project. They were given a pretest before the start of the project, finding out the initial knowledge about bio-waste and their opinion on the classification of bio-waste. After the project, the pupils completed a posttest and by comparing the individual answers, it was determined whether and how the knowledge of the tested pupils and their attitude towards the topic changed. The answers of individual pupils in the pretest and posttest were evaluated...
497

The use of bimetallic heterogeneous oxide catalysts for the Fenton reaction

Mgedle, Nande January 2019 (has links)
M.Tech. (Department of Chemistry, Faculty of Applied and Computer Sciences), Vaal University of Technology / Water contaminated with non-biodegradable organics is becoming increasing problematic as it has a hazardous effect on human health and the aquatic environment. Therefore, the removal of organic contaminants is of importance and an active heterogeneous Fenton catalyst is thus required. The literature indicates that a bimetallic oxide Fenton catalyst is more active than an iron oxide catalyst. This study focused on increasing the activity of iron-based Fenton catalysts with the addition of transition metals such as manganese, cobalt and copper and optimizing the preparation method. In this study, bimetallic oxide (Fe-Cu, Fe-Mn, Fe-Co) and monometallic oxide (Fe, Cu, Mn,Co) catalysts supported on silica SiO2 where prepared by incipient wetness impregnation. The total metal oxide contents were kept constant. The catalysts where calcined in two different ways, in a conventional oven and in a microwave. These catalysts were characterized with XRD, XPS and CV and were tested for the degradation of methylene blue dye at 27°C. The catalysts calcined in a microwave oven had a higher catalytic activity than those prepared in a conventional oven. The bimetallic oxide catalysts outperformed the mono- metallic oxide catalysts in the degradation of methylene blue. The Fe2MnOx prepared by microwave energy were the most active catalyst yielding the highest percentage of degradation of methylene blue dye (89.6%) after 60 minutes. The relative amounts of manganese and iron oxide were varied while keeping the total metal content in the catalyst the same. The optimum ratio of Fe to Mn was 1:7.5 since it yielded the most active catalyst. A 96.6 % removal of methylene blue was achieved after 1 hour of degradation. Lastly this ratio 1Fe:7.5Mn was prepared by varying different microwave power (600, 700 and 800 W) and irradiation time (10, 20 and 30 min). The optimum microwave power and irradiation time was 800W and 10 min with the methylene blue percentage removal of 96.6 % after 1 hour of degradation.
498

Produktdesign för ett ekologiskt hållbart sportfiske / Product design for ecologically sustainable sport fishing

Carlsson, Axel January 2023 (has links)
Fiske förekommer runt om i hela världen, men det utförs av många olika anledningar. Det kan vara ett yrke, en hobby eller ett sätt att få mat på bordet. Men oavsett syftet kan beten gå sönder, fastna eller lossna. I Norden tappar vi uppskattningsvis 28 miljoner beten varje år. Att beten lossnar är inte något som alla kan påverka eller undvika. Något som däremot går att ändra är vilka beten vi faktiskt använder oss av och vilka material de består av. Det finns en mängd olika fiskeutövare som skulle kunna dra nytta av ny forskning inom området och det är på tiden att vi anammar ett mer hållbart sportfiske. Studien undersöker hur ett ekologiskt hållbart fiskedrag i form av en jigg kan framtas genom en materialcentrerad designprocess. Med hjälp av materialdriven design och användarcentrerad design undersöks möjligheterna att ersätta syntetiska plaster med bioplaster, i ett mjukt plastbete. Designmetoder användes för att granska och bekräfta problemet med förlorade fiskedrag. Marknadsanalyser, deltagande observationer och intervjuer utfördes med verksamma inom sport- och hobbyfiske. Metoderna gav en bredare uppfattning av problemet och vilka förbättringsmöjligheter som fanns. Olika prototyper skissades och framtogs genom bioplaster. För att säkerställa att produkten lever upp till användarnas krav, genomgick prototyperna olika tester, samt utvärderas. Studien ger ett kunskapsbidrag om vilka material som fungerar och vilka som inte fungerar vid tillverkning av mjuka plastdrag. Den visar dessutom hur massproducerade formar skulle kunna uppmana hobbyfiskare att tillverka sina egna drag. Det framgår också hur man från grunden kan framställa egna fiskedrag genom ett DIY-projekt. Studien resulterar även i två bionedbrytbara produkter. En produkt för abborrefiske och en för gäddfiske. / Fishing occurs throughout the entire planet, but it occurs for different reasons. It could be a profession, a hobby or a livelihood. Regardless, the bait can break, get stuck or get loose. In the North we lose around 28 million baits every year. The fact that lures is not something that everyone can influence or avoid. However, something that can be changed, is which lures we use and which materials they are made of. There are a variety of anglers who could benefit from new research in this field, and it is about time we embrace a more sustainable sport fishing. This study examines how an ecologically sustainable fishing lure in the shape of a jig, can be produced through a material centered design process. With material driven design and user centered design, this study investigates the possibilities of replacing synthetic plastics with bioplastics in a soft plastic bait. Several design methods were used to research and confirm the problem of lost fishing lures. Market analyses, participant observations and interviews were done with people active in sport- and hobby fishing. These methods gave a broader perception of the problem and which opportunities there are. Different prototypes were sketched and then made by bioplastics. The prototypes were evaluated through different tests, to ensure that the products will live up to the requirements presented by the users. This study provides knowledge about which materials work, and which do not when manufacturing soft plastic features. It also shows how mass-produced molds could encourage hobby anglers to make their own lures. It’s also shown how you can make your own fishing lures from scratch, through a DIY project. The study also results in two biodegradable products. One product for perch fishing and one for pike fishing.
499

POSS-Based Biodegradable Polymers for Stent Applications: Electroprocessing, Characterization and Controlled Drug Release

Guo, Qiongyu January 2010 (has links)
No description available.
500

Bioresorbable Magnesium-Based Bone Fixation Hardware: Alloy Design, Post-Fabrication Heat Treatment, Coating, and Modeling

Ibrahim, Hamdy, Ibrahim January 2017 (has links)
No description available.

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