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An Approach to eBook Topics Trend Discovery Based on LDA and Usage LogHung, Chung-yang 13 February 2012 (has links)
With the growth of digital content industry, publishers start to provide online services for ebook search, reading and downloading. Users can access to online resources from anywhere, any place with laptop or mobile devices at any time. Nowadays more and more libraries have purchased ebooks as an important part of the library collection. To access the online resources users can link directly to publisher's ebook portal or via the OPAC system. Compared to the library circulation process, ebooks are more convenient to patrons and improve the utilization of library online resources.
There are various kinds of ebooks available in the market, so libraries have to focus their investment on the most valuable online resources. Usage statistics report plays an important role in providing valuable information to libraries. It is usually based on the standard of COUNTER to generate the statistic reports, although it provides when and where users access to specific ebooks, it fails show the general topics and how they change.
In this study, we introduce a post process method to weighting the LDA topic model via the usage statistic report to emphasize the changes of topic and compare it to the classification method and subject heading method in the bibliographic, namely LCC and LCSH respectively. The result show that weighted topic model significantly affect the ranking of topics, and the topic model are independent from the classification method and the subject heading method in the bibliographic record.
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Environmental and Economic Assessment of Swedish Municipal Solid Waste Management in a Systems PerspectiveEriksson, Ola January 2003 (has links)
<p>Waste management is something that affects most people. Thewaste amounts are still increasing, but the waste treatment ischanging towards recycling and integrated solutions. In Swedenproducersresponsibility for different products, a taxand bans on deposition of waste at landfills implicates areorganisation of the municipal solid waste management. Plansare made for new incineration plants, which leads to that wastecombustion comes to play a role in the reorganisation of theSwedish energy system as well. The energy system is supposed toadapt to governmental decisions on decommission of nuclearplants and decreased use of fossil fuels.</p><p>Waste from private households consists of hazardous waste,scrap waste, waste electronics and wastes that to a largeextent are generated in the kitchen. The latter type has beenstudied in this thesis, except for newsprint, glass- and metalpackages that by source separation havent ended up in thewaste bin. Besides the remaining amount of the above mentionedfractions, the waste consists of food waste, paper, cardboard-and plastic packages and inert material. About 80-90 % of thismixed household waste is combustible, and the major part ofthat is also possible to recycle.</p><p>Several systems analyses of municipalsolid waste managementhave been performed. Deposition at landfill has been comparedto energy recovery, recycling of material (plastic andcardboard) and recycling of nutrients (in food waste).Environmental impact, fuel consumption and costs are calculatedfor the entire lifecycle from the households, until the wasteis treated and the by-products have been taken care of.</p><p>To stop deposition at landfills is the most importantmeasure to take as to decrease the environmental impact fromlandfills, and instead use the waste as a resource, therebysubstituting production from virgin resources (avoidingresource extraction and emissions). The best alternative tolandfilling is incineration, but also material recycling andbiological treatment are possible.</p><p>Recycling of plastic has slightly less environmental impactand energy consumption than incineration. The difference issmall due to that plastic is such a small part of the totalwaste amount, and that just a small part of the collectedamount is recycled. Cardboard recycling is comparable toincineration; there are both advantages and disadvantages.Source separation of food waste may lead to higher transportemissions due to intensified collection, but severalenvironmental advantages are observed if the waste is digestedand the produced biogas substitutes diesel in busses.Composting has no environmental advantages compared toincineration, mainly due to lack of energy recovery. Therecycling options are more expensive than incineration. Theincreased cost must be seen in relation to the environmentalbenefits and decreased energy use. If the work with sourceseparation made by the households is included in the analysis,the welfare costs for source separation and recycling becomesnon-profitable. It is however doubted how much time is consumedand how it should be valuated in monetary terms.</p><p>In systems analyses, several impacts are not measured.Environmental impact has been studied, but not allenvironmental impact. As the parts of the system are underconstant change, the results are not true forever. Recyclingmay not be unambiguously advantageous today, but it can be inthe future.</p><p>Despite the fact that systems analysis has been developedduring 10 years in Sweden, there are still many decisions takenregarding waste management without support from systemsanalysis and use of computer models. The minority of users ispleased with the results achieved, but the systems analysis isfar from easy to use. The adaptation of tools and models to thedemands from the potential users should consider thatorganisations of different sizes have shifting demands andneeds.</p><p>The application areas for systems analysis and models arestrategic planning, decisions about larger investments andeducation in universities and within organisations. Systemsanalysis and models may be used in pre-planning procedures. Apotential is a more general application (Technology Assessment)in predominantly waste- and biofuel based energy processes, butalso for assessment of new technical components in a systemsperspective. The methodology and systems approach developedwithin the systems analysis has here been transformed to anassessment of environmental, economic and technical prestandaof technical systems in a broad sense.</p>
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HÅLLBART BYGGANDEMED HJÄLP AV BIM : Effektiva energianalyser och LCC / SUSTAINABLE BUILDING USING BIM : Efficient Energy Analyzes and LCCMika, Jonas, Fossland, Andreas January 2015 (has links)
The society strives for sustainable development, in the construction industry it is expressed through sustainable building. Energy and LCC analyzes increases the ability to make conscious decisions in the process. A problem in the construction industry is that energy and LCC analysis is not used to the desired extent, as they are perceived as complicated and time consuming. The report aims to achieve a more sustainable building through increased use of energy and LCC analyzes.The goal is to show how BIM can be used to improve the efficiency of the energy and LCC analyzes. The study was conducted with a literature review and a case study to answer which information that is required in a BIM model to perform energy and LCC analyzes. The study also shows which software can be used in BIM based energy and LCC analyzes and how the analyzes can be carried out efficiently. The result shows that effective analyzes may be performed if the BIM-model contains the relevant information for making analyzes. Information not necessary for the analysis complicates the procedure. There are a variety of software that manages energy and LCC analyzes differently. The Software’s are optimized for different BIM platforms and they use various file formats for the transfer of information. Effective analyzes are achieved by following a proven method or guide with few steps in the workflow. Through knowledge of the capability of the used file format, the right information can be added to the model at the right point in the process of analyzes without loss of information. To increase the use of energy and LCC analyzes, an integration of the analysis tools into the BIM platforms would be necessary. / Samhället strävar efter ett allt mer hållbart byggande som reducerar påfrestningarna på miljön. Energi- och LCC-analyser(LifeCycleCosting, eller Livscykelkostnad) ökar möjligheten att fatta medvetna beslut i processen. Ett problem inom byggbranschen är att energi- och LCC-analyser inte används i önskad utsträckning då de upplevs som komplicerade och tidskrävande. Syftet med rapporten är att få ett mer hållbart byggande genom en ökad användning avenergi- och LCC-analyser. Målet är att visa hur BIM kan användas för att effektivisera energi- och LCC-analyser. Studien har gjorts med en litteraturstudie och en fallstudie för att besvara vilkeninformation som krävs i en BIM-modell för att utföra energi- och LCC-analyser. Studien visar även vilka mjukvaror som kan användas vid BIM-baserade energi och LCC-analyser och hur analyserna kan utföras på ett effektivt sätt. Resultatet visar att effektiva analyser kan genomföras om BIM-modelleninnehåller relevant information för att göra analyser. Annan informationkomplicerar analysförfarandet. Det finns en stor mängd olika mjukvaror somhanterar energi- och LCC-analyser på olika sätt. Mjukvarorna som kan göra energianalyser är optimerade för olika BIM-plattformar och använder olika filformat för informationsöverföring. Genom kunskap om filformatens kapacitet, kan rätt information tillföras modellen vid rätt moment i analysprocessen utan att information går förlorad. För att göra effektiva analyser, är användandet av en beprövad metod eller guide önskvärt. En möjlighet för att öka användandet av energi- och LCC-analyser, skulle vara att en integration av analysverktygen in i BIM-plattformarna utvecklades.
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Parametric energy modeling tool for climate dependent guidelinesMorales, Cristian Enrique 21 November 2013 (has links)
The purpose of this thesis is to develop a simple tool that can help designers and researchers obtain general guidelines for buildings in terms of energy usage and LCC. Another objective of this thesis is to apply this tool to residential buildings in order to understand which variables are relevant in terms of energy consumption and LCC costs. A one-story rectangular house was parameterized in terms of five variables: total glazing area; south window-to-wall ratio (WWR); east and west WWR (which are symmetrical for these two facades); insulation width; and window type (ranging from a single clear window to a double low e-clear argon filled window). A high average glazing area (30-40% of floor area) was applied in order to increase energy loads and to augment the importance of the window properties. Simulation was performed through Energy-plus (in conjunction with a code developed especially for this project) for three cities: Austin, Boston, and Seattle. A total of 1055 simulations were run for each city. The experiment showed that only the total glazing area, the E-W WWR and the window types were relevant variables. The former variable is highly correlated with total energy consumption across all cities. Another important conclusion was that each variable's effect on energy consumption worked independently of each other, as there were no considerable differences when analyzing variables individually, as opposed to analyzing them holistically. Results showed that, for Austin and Boston, it was possible to reduce energy loads by 35% and 27% respectively with a double low-e green window (as compared to a single clear window). Similarly, Seattle showed a reduction of 29% for a double low e-clear argon filled window. Nevertheless, the simplest type of window (type 1) presented the best results in terms of LCC. Therefore, we can conclude that only under a high-energy demand situation, such as with office buildings, would it be possible to obtain positive LCC results for double glazed windows. Consequently, double glazed windows will not present positive economical results in typical residential buildings. A second simulation was performed under a tighter HVAC schedule and higher internal loads. In this new scenario, the best windows were the same as with the first simulation, but maximum energy savings were higher: 50%, 34% and 35% for Austin, Boston, and Seattle, respectively. Nevertheless, when considering LCC, a double-clear window presented the best results for Austin, Boston, and Seattle, with 17%, 11%, and 5% reductions in costs respectively compared to the type 1 window. Therefore, if designers are only concerned with costs, the problem of what window to choose becomes non-trivial only for high-energy demand cases. / text
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Beredning av köldbärare för komfortändamål i kontorsverksamhet : En studie i produktionsslag / Preparation of secondary refrigerants for comfort purposes in office premisesRolin, Jacob, Vestberg, Pontus January 2014 (has links)
The real estate company Ihus is facing an expansion of its comfort cooling in Noatun,Uppsala, to provide the buildings in the block with cooling. The buildings in Noatunare mainly used for office premises, where the requirements for an accepted indoorclimate is great. However, it’s uncertain whether Ihus should continue, as currently,producing comfort cooling by themselves using a compressor chiller, or if they shouldconnect themselves to Vattenfall’s district cooling net. The purpose of this report is to examine which technique of cooling is best suited forIhus and their buildings in Noatun. It should also work as a guideline for othercompanies facing the same problem as Ihus. In addition, the result should give an ideaof how cooling by using compressor chillers compares to district cooling in aneconomical perspective, aswell as in an environmental and performance perspective. This report is based mainly on studies of literature covering cooling, approximationsof contractor costs with the help of the calculation tool Wikells Sektionsdata andassays of life cycle costs for different refrigeration alternatives. The result is showing that refrigeration by using compressor chillers seems to be themost advantageous option for the buildings in Noatun. Investments of a newcompressor chiller and associated components to cover the cooling demand in theblock appears to be a better option than district cooling.The costs of district cooling varies greatly depending on its origin and geographicallocation. Because of these great variations, it’s difficult to come to a conclusion onwhat type of comfort cooling is the least expensive in all situations. Every uniquesituation requires an investigation.In order to determine the impact on the environment for each type of comfortcooling a more thoroughly analysis is required. However, district cooling is likely tobe a better option regarding the environmental impact due to a centralizedpreparation of the refrigerants. A centralized preparation allows easier environmentalefficiency work since it’s easier to oversee emissions in one large facility than in manysmaller ones. The performance of different types of comfort cooling has shown to be too difficultto compare in this report. The reason for this is mainly because of limited access ofinformation regarding performance, but also because district cooling and cooling byusing compressor chillers differs greatly technically. Therefore, it’s difficult to conducta fair comparison of their performance.
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Obten??o de pol?meros de LCC para aplica??o como antioxidante de biodiesel de sojaFigueiredo, Francisco Cardoso 06 August 2009 (has links)
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Previous issue date: 2009-08-06 / Biodiesel is a fuel obtained from vegetable oils, such as soy, castorbean, among others. The monoester of fatty acid of these oils have chains with mono, di and tri double connections. The presence of these insaturations are susceptible to oxidization. Antioxidants are substances able to prevent oxidization from oils, fats, fat foods, as well as esters of Alquila( biodiesel). The objective of this work is to summarize a new antioxidant from the Cashew Nut Shell Liquid (CNSL) using the electrolysis technique. A current of 2 amperes was used in a single cell of only one group and two eletrodos of stainless steel 304 in a solution of methanol, together with the eletrolits: acetic acid, sodium chloride and sodium hydroxide, for two hours of agitation. The electrolysis products are characterized by the techniques of cromatography in a thin layer, spectroscopy of infrared and gravimetric analysis. The material was submitted to tests of oxidative stability made by the techniques of spectropy of impendancy and Rancimat (EN 14112). The analyses of characterization suggest that the polimerization of the electrolytic material ocurred. The application results of these materials as antioxidants of soy biodiesel showed that the order of the oxidative stability was obtained by both techniques used / Biodiesel ? um combust?vel obtido a partir de ?leos vegetais como soja, mamona, etc. Os monos ?ster de ?cidos graxos desses ?leos possuem cadeias com com mono, di e tri liga??es duplas. A presen?a destas insatura??es s?o suscept?veis a oxida??o. Antioxidantes s?o subst?ncias capazes de inibir oxida??o l?p?dica de ?leos, gorduras, alimentos gordurosos, bem como ?steres de alquila (biodiesel). O objetivo deste trabalho foi sintetizar um novo antioxidante a partir do l?quido da castanha de caju (LCC), utilizando a t?cnica da eletr?lise. Fez-se passar uma corrente de 2 ?mperes em uma ?nica c?lula de um s? compartimento e dois eletrodos de a?o inoxid?vel 304 em solu??o de metanol, na presen?a dos eletr?litos: ?cido ac?tico, cloreto de s?dio e hidr?xido de s?dio, por duas horas sob agita??o. Os produtos de eletr?lise foram caracterizados pelas t?cnicas de cromatografia em camada delgada, espectroscopia de infravermelho e an?lise termo gravim?trica. O material caracterizado foi submetido a testes de estabilidade oxidativa realizados pelas t?cnicas de espectroscopia de imped?ncia e de rancimat (EN 14112). As an?lises da caracteriza??o sugerem que ocorreu a polimeriza??o do material eletrolisado. Os resultados da aplica??o desses materiais como antioxidantes de biodiesel de soja mostraram que a ordem de estabilidade oxidativa foi: LSAL > LELET > LCC T?CNICO > KEROBIT > LACAC > LSODA, obtida pelas duas t?cnicas utilizadas
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Integrering av LCA och LCC i en multikriterieanalys : Optimering av byggnadsdelar / Integration of LCA and LCC into a multicriteria decision analysis : Optimization of construction partsLunnergård, Filip, Nilsson, David January 2018 (has links)
Syfte: Detta examensarbete behandlar integrering av miljöbelastning och kostnader vid projektering av byggnader. Enligt tidigare forskning och svenska rapporter är användningen av livscykelkostnader och livscykelanalyser begränsad inom byggsektorn. Än mer begränsad är sammanvägning av dessa analyser för optimering av byggdelar och hela byggnadsverk. Målet med detta examensarbete är därför att testa en konceptmodell vilken syftar till att integrera miljöbelastning och kostnader under en hellivscykel. Frågeställningarna som besvaras är ”Hur kan fasadmaterial utvärderas utifrån miljömässiga och ekonomiska aspekter?” och ”Hur kan kostnader och miljöbelastning sammanvägas för att skapa beslutsunderlag för val avfasadmaterial?”. Metod: Konceptmodellen prövas genom en fallstudie där ett antal fasader utgör fallet. Dessutom jämförs resultaten från fallstudien med inhämtade data från genomförd litteraturstudie. Resultat: Studien visar att den testade konceptmodellen fungerar med hjälp av relativt enkla verktyg. En multikriterieanalys genomförs på resultaten från LCA och LCC vilket genererar jämförbara slutvärden för fasaderna. Konsekvenser: Slutsatser som kan dras utifrån studien är att LCA och LCC är relativt enkla att genomföra i tidiga skeden om schablonvärden för livslängder kan nyttjas och modellinläsning mot en färdig miljödatabas finns tillgänglig. Vidare visar studien att multikriterieanalysen COPRAS är lämplig för integrering av miljöpåverkan och kostnader. Vidare studier på konceptmodellen bör genomföras med hjälp av intervjuer i branschen. Begränsningar: Studiens resultat begränsas av det faktum att den genomförs som en fallstudie där författarna bedömer huruvida konceptmodellen går att använda eller ej. För större förståelse kring hur användbar den är i praktiken och vilka modifieringar som bör genomföras måste branschens åsikter beaktas, exempelvis med hjälp av intervjuer.
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Vývojová a traumatická onemocnění kolenního kloubu u psa. / Developmental and traumatic diseases of the knee joint in dog.Špatenková, Dana January 2016 (has links)
Patellar luxation is a condition subject to heredity. It varies in gravity depending on its clinical grade and on the duration of luxation. Patellar luxation may be medial which is more common type and lateral which is less common. Often the only way to sustain a comfort of a dog patient and its normal use of a hind limb is surgical management. Considering a hereditary and congenital aspect of patellar luxation we see that it is an important breeding problem and some measures should be taken to stop its spread in breeds.
The cranial cruciate ligament rupture is mostly traumatic in origin and affects especially large and giant breed dogs although all breeds may be affected. In the lower percentage of cases there is possible a degenerative origin of the disease. There is a higher prevalence of the disease in older and less active dogs. After a diagnosis of a LCC rupture surgical intervention should be implied and performed as soon as possible to put an end to the progress of arthrotic changes and to sustain the patients comfort.
This master thesis was also concerned with original research examining 23 dogs with patellar luxation or LCC rupture, two dogs of these afflicted with both. Hypotheses of the thesis introduction have been mostly confirmed, LCC rupture afflicted especially overweight or obese individuals (56%), predominant affliction of females has been also confirmed (56%), partly also increased affliction of neutered animals (25% females, 6% males). Medial patellar luxation is distinctively more common than lateral one, the hypothesis has been confirmed, medial patellar luxation afflicted 100% of the dogs. Medial patellar luxation affects mostly small and miniature breeds, the hypothesis has been confirmed, all examined dogs were of small or miniature breed (100%).
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Macromoléculas derivadas do cardanol hidrogenado: síntese e propriedades líquido cristalinas / Derived from the macromolecules cardanol hydrogenated: synthesis and liquid crystalline propertiesMota, João Paulo Ferreira January 2016 (has links)
MOTA, J. P. F. 2016. 110 f. Macromoléculas derivadas do cardanol hidrogenado: síntese e propriedades líquido cristalinas. Tese (Doutorado em Química)-Universidade Federal do Ceará, Fortaleza, 2016. / Submitted by Aline Mendes (alinemendes.ufc@gmail.com) on 2016-10-25T23:39:37Z
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Previous issue date: 2016 / In this study were obtained some macromolecules, new asymmetric meso-porphyrins and phthalocyanines, derived from hydrogenated cardanol, the majority constituent of the cashew nut shell liquid (technical CNSL). Where, in addition, it was evaluated the liquid crystalline properties of these compounds in heating and cooling cycles. The data obtained by spectroscopic and spectrometric methods, 1H and 13C NMR, UV-vis, MS (MALDI-TOF) and IR have indicated the efficiency of the synthetic procedure, that allowed us, to obtain the new meso-5-mono-4-hydroxyphenyl-10,15,20-tri-4-[2-(3-pentadecylphenoxy)ethoxy]phenyl por-phyrin free and metalated with nickel, cobalt, copper and zinc, as well as the 2(3),9(10),16(17),23(24)-tetrakis(-3-pentadecylphenoxy) phthalocyanine free and metallated with cobalt, nickel, zinc and copper. The precursors produced in this study, 1-(2-bromoethoxy)-3-pentadecylbenzene (compound 1), 4-[2-(3-pentadecylphenoxy)ethoxy] benzaldehyde (compound 2) e 4-(3-pentadecylphenoxy)phthalonitrile (compound 3), were purified by two different procedures: column chromatography (a) and recrystallization (b). Whereas for the last, a significant reduction in the generation of residues were observed, when comparing the chromatography, which on average, 200 g of silica gel and 1650 mL of solvent were used. The liquid crystalline properties of the macromolecules were measured by means of images obtained in polarized optical microscopy (POM), during heating and cooling cycles. These images show that only free phthalocyanine 2(3),9(10),16(17),23(24)-tetrakis(-3-pentadecylphenoxy) self-organizes, displaying focal conic textures, which were observed in liquid crystal phases. Another compound that showed evidence of an organized phase was the cobalt 2(3),9(10),16(17),23(24)-tetrakis(-3-pentadecylphenoxy) phthalocyanine. However, the results of X-rays diffraction analysis suggest that only the free phthalocyanine showed the formation of a liquid crystalline phase with discotic hexagonal columnar structure (Colh). / Neste trabalho foram obtidas algumas macromoléculas, novas meso-porfirinas assimétricas e ftalocianinas, derivadas do cardanol hidrogenado, o constituinte majoritário do Líquido da Casca da Castanha de Caju (LCC técnico). Onde, além disso, foi avaliado as propriedades liquido cristalinas destes compostos em ciclos de aquecimento e resfriamento. Os dados obtidos por meio de métodos espectroscópicos e espectrométricos, RMN 1H e 13C, UV−vis, EM (Maldi−TOF) e IV, indicaram a eficiencia do procedimento sintético que possibilitou obter a nova meso-5-mono-4-hidroxifenil-10,15,20-tri-4-[2-(3-pentadecilfenoxi)etoxi]fenil porfirina livre e metalada com níquel, cobalto, cobre e zinco, bem como a 2(3),9(10),16(17),23(24)-tetrakis(-3-pentadecilfenoxi) ftalocianina livre e metalada com cobalto, níquel, zinco e cobre. Os precursores produzidos neste trabalho, 1-(2-bromoetoxi)-3- pentadecilbenzeno (composto 1), 4-[2-(3-pentadecilfenoxi) etoxi]benzaldeido (composto 2) e 4-(3-pentadecilfenoxi)ftalonitrila (composto 3), foram purificados por dois procedimentos distintos: cromatografia em coluna (a) e recristalização (b). Sendo que no último, foi observado uma redução significativa na geração de resíduos, quando comparamos esta metodologia com a cromatografia em coluna, onde em média 200 g de gel de sílica e 1650 mL de solvente foram utilizados. As propriedades liquido cristalinas das macromoléculas foram avaliadas por meio de imagens obtidas na microscopia óptica de luz polarizada (MOLP) em ciclos de aquecimento e resfriamento. Estas imagens mostraram que apenas a ftalocianina 2(3),9(10),16(17),23(24)-tetrakis(-3-pentadecilfenoxi) livre se auto-organiza exibindo texturas cônica focal, a qual é observada em fases liquido cristalinas. Outro composto que apresentou indícios de uma fase organizada foi a cobalto 2(3),9(10),16(17),23(24)-tetrakis(-3-pentadecilfenoxi) ftalocianina. No entanto, os resultados das análises de difração de raios-X sugerem que apenas a ftalocianina livre apresentou a formação de uma fase líquido cristalina com estrutura discótica colunar hexagonal (Colh ).
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Obtaining and characterization of magnetic nanosystems derived of CNSL / ObtenÃÃo e caracterizaÃÃo de nanosistemas magnÃticos derivados do lccViviane Gomes Pereira Ribeiro 29 June 2013 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Nanotechnology has received great prominence in recent years due to the versatility of new materials and its applications at the various sectors of society. The functionalized magnetic nanoparticles have been the focus of intense research because of the ability to use on different systems, with emphasis on the catalytic processes of environmental decontamination. In particular, we have seen a growing demand for hybrid catalysts capable of utilizing sunlight, constructed from TiO2 particles by photosensitised dyes. Thus, this study aimed to develop a new magnetic nanosystem, based on use of meso-porphyrins derived from Cashew Nut Shell Liquid (CNSL), coated with TiO2, with potential application in heterogeneous photocatalysis. Moreover, produce a new ferrofluid derived biomass from the anacardic acid (AA MAG). To this end, were synthesized Fe3O4 nanoparticles with an average size of 11nm, coated with a 1st layer of oleic acid and a 2nd layer of meso-porphyrin (3-n-PDPP). This nanosystem also was covered with a layer of TiO2. This procedure produced a new magnetic nanosystem of porphyrin (NMP). The new ferrofluid AA-MAG and magnetic nanosystems were characterized by Transmission Electron Microscopy (TEM), infrared spectroscopy, Thermal analysis (TG) and magnetization curves. The results showed that NMP showed good thermal stability, superparamagnetic behavior and dimension nanometric (≈ 14nm). The fluorescent properties were little affected, which enables its application in photocatalytic systems. / A nanotecnologia vem recebendo grande destaque nos Ãltimos anos graÃas à versatilidade dos novos materiais gerados e suas aplicaÃÃes nos diversos setores da sociedade. As nanopartÃculas magnÃticas funcionalizadas tÃm sido foco de intensas pesquisas devido à capacidade de utilizaÃÃo em diferentes sistemas, com destaque para os processos catalÃticos de descontaminaÃÃo ambiental. Em especial, tem-se observado uma crescente demanda por catalisadores hÃbridos capazes de utilizar a luz solar, construÃdos a partir de partÃculas de TiO2 fotossensibilizadas por corantes. Assim, o presente trabalho teve por objetivo desenvolver um novo nanosistema magnÃtico, baseado no emprego de meso-porfirinas derivadas do LÃquido da Casca da Castanha de Caju (LCC), recobertas com TiO2, com potencial aplicaÃÃo em fotocatÃlise heterogÃnea. AlÃm disso, produzir um novo ferrofluido derivado da biomassa, a partir do Ãcido anacÃrdico (AA-MAG). Para isso, foram sintetizadas nanopartÃculas de Fe3O4 com tamanho mÃdio de 11nm, revestidas por uma 1 camada de Ãcido oleico e uma 2 camada da meso-porfirina (3-n-PDPP). Esse nanosistema tambÃm foi recoberto por uma camada de TiO2. Este procedimento produziu um segundo novo nanosistema magnÃtico de porfirina (NMP). O novo ferrofluido AA-MAG e os nanosistemas magnÃticos foram caracterizados por Microscopia eletrÃnica de trasmissÃo (MET), Espectroscopia no Infravermelho, AnÃlise tÃrmica (TG) e curvas de magnetizaÃÃo. Os resultados mostraram que o NMP apresentou uma boa estabilidade tÃrmica, comportamento superparamagnÃtico e dimensÃes nanomÃtricas (≈ 14nm). As propriedades fluorescentes foram pouco afetadas, o que possibilita sua aplicaÃÃo em sistemas fotocatalÃticos.
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