Dissertations / Theses: 'Paper'

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Mendes, Afonso Henrique Teixeira. "Higroexpansibilidade de papel reprográfico produzido com fibras de eucalipto em máquina industrial." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-09072006-172911/.

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Como qualquer material fabricado a partir de fibras de madeira, o papel também apresenta variações dimensionais decorrentes de modificações no seu teor de umidade. O presente trabalho aborda o comportamento desta propriedade do papel, denominada higroexpansibilidade, medida em papel reprográfico fabricado a partir de fibras de eucalipto, durante o processo de produção em uma máquina industrial. O estudo foi realizado com amostras de papel de 75 g/m2, coletadas em diversos pontos de uma máquina comercial, operando à velocidade de 1256 m/min. No estudo, encontram-se dados de higroexpansibilidade medidos ao longo da máquina de papel, desde a seção de formação até o acabamento, e na direção transversal da folha na enroladeira. A análise dos resultados permite a verificação de influências das operações e tratamentos envolvidos na fabricação do papel (formação, prensagem, secagem e acabamento) sobre a sua higroexpansibilidade. Os resultados das medições desta propriedade são discutidos em termos de efeitos provenientes das condições operacionais estabelecidas para a fabricação do papel, permitindo reconhecer influências da orientação de fibras, do processo de secagem e da restrição ao encolhimento, da aplicação de amido superficial e da aplicação de tensões na direção longitudinal e transversal do papel. Para comparação e suporte à discussão de resultados, foram também medidas propriedades estruturais, de resistência e propriedades elásticas do papel. Na conclusão do trabalho, são apresentadas sugestões para controle e minimização da higroexpansibilidade do papel destinado ao uso final, com enfoque em ações a serem tomadas, no que se refere ao ajuste do processo de fabricação. Finalmente, apresentam-se comentários sobre futuros trabalhos que poderão ser desenvolvidos, a fim melhor entender fenômenos adicionais relacionados à higroexpansibilidade e buscar alternativas para seu controle, por se tratar de uma propriedade cada vez mais importante para os processos de impressão e operações de conversão, cujos efeitos podem limitar o desempenho e a utilização final do papel.
Like any material made from wood fibers, the paper also exhibits dimensional changes as a result of change in moisture content. This work deals with the behavior of this paper property, called hygroexpansivity, which was measured in reprographic paper manufactured from eucalyptus fibers, during the production process in an industrial paper machine. The study was developed using 75 g/m2 paper samples collect in different positions of a commercial paper machine running at the speed of 1256 m/min. In the study, data of hygroexpansivity measured along the paper machine can be found from the forming section up to the finishing section and from the cross machine direction at the reel. The analysis of the results reveals the effects of the operations and treatments involved in the papermaking (formation, pressing, drying and finishing) on the hygroexpansivity. The measurements results of this property are discussed with focus on the effects of the operating conditions established for the papermaking operation, what leads to the recognition of the effects of the fiber orientation, drying process, shrinkage restraint, starch sizing and tensions applied to the paper in machine direction and cross machine direction. For comparison purposes and result discussion support, some structural, strength and elastic paper properties were also measured. In the conclusion of the study, some suggestions for control and minimization of hygroexpansivity of the end use paper are presented, focusing on actions to be taken, which are related to the adjustment of papermaking process. Finally, comments referred to future work for better understanding of additional hygroexpansivity mechanisms are also mentioned, in order to suggest future investigation of control alternatives for this property, since its importance has been more and more highlighted in printing and conversion operations because, at times, it can limit the performance and usefulness of paper.

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Klem, Maykel dos Santos. "Estudo de supercapacitores orgânicos impressos em papel à base de PEDOT:PSS /." Bauru, 2017. http://hdl.handle.net/11449/152154.

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Orientador: Neri Alves
Banca: Rodrigo Lassarote Lavall
Banca: Clarissa de Almeida Olivati
Resumo: Realizou-se primeiramente neste trabalho o estudo de um supercapacitor padrão utilizando coletores de aço inox e eletrodos de grafite Aquadag®. Este dispositivo apresentou uma capacitância máxima de 22 F/g, e seu espectro de impedância foi modelado por um circuito do tipo R(C(RW))(RC)(RC). Com este dispositivo foi possível testar os métodos de produção dos supercapacitores, e identificar as características desejáveis no supercapacitor impresso. Foram testadas duas técnicas de impressão distintas visando o preparo de eletrodos e coletores de corrente impressos em papel para aplicação em supercapacitores. O material ativo utilizado nos eletrodos foi basicamente o PEDOT:PSS, com a adição de óxido de grafeno, grafite aquadag® e nanotubos de carbono de paredes múltiplas (MWNT) para a formação compósitos condutores. Foram realizadas caracterizações morfológicas e elétricas nas superfícies dos eletrodos impressos em papel filtro, vegetal e sulfite. Os eletrodos produzidos por serigrafia utilizando o compósito de PEDOT:PSS com MWNT impressos em papel filtro apresentaram os menores resultados de resistência de folha (17 Ω/sqr), sendo assim utilizados na produção dos supercapacitores. O supercapacitor impresso em papel apresentou um bom comportamento capacitivo através de medidas de espectroscopia de impedância e voltametria cíclica. A curva de impedância foi modelada através de um circuito do tipo R(RC)(C(RQ))(RC), evidenciando uma alta capacitância de dupla camada. Foi encontrada uma... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: In this study, we first produced a standard supercapacitor using stainless steel collectors and Aquadag® graphite electrodes. The device exhibited a maximum capacitance of 22 F/g, and an R(C(RW))(RC)(RC) circuit modeled its impedance spectrum. With this device was possible to test the production methods of supercapacitors, and identify its desirable characteristics. Two different printing techniques were tested to produce electrodes/current collectors. The active material used in the electrodes was PEDOT: PSS, with addition of graphene oxide, Aquadag® graphite and multi-walled carbon nanotubes (MWNT), in order to obtain conductive composites. Morphological and electrical characterizations were performed over the surfaces of printed electrodes onto filter, vegetable and bond paper. The electrode produced by screen-printing using the PEDOT: PSS/MWNT composite printed onto filter paper exhibited low sheet resistance (17 Ω /sqr), being used in the production of supercapacitors. Printed supercapacitor showed good capacitive behavior through impedance spectroscopy and cyclic voltammetry measurements. An R(RC)(C(RQ)(RC) circuit modeled the impedance spectrum, evidencing a high double layer capacitance. A maximum specific capacitance of 20.3 F / g was found for a charge/discharge current of 1 mA, and an equivalent series resistance of 60 Ω. These values led to energy and power densities of 3.1 Wh / kg and 420 W / kg, respectively. Simulations and curve fitting were also performed fro... (Complete abstract click electronic access below)
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Taparelli, Jesus Roberto. "Modificação quimica do amido de mandioca e estudo de sua aplicação em revestimento couche." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266135.

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Orientador: Lucia Helena Innocentini Mei
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
Made available in DSpace on 2018-08-04T05:33:53Z (GMT). No. of bitstreams: 1 Taparelli_JesusRoberto_M.pdf: 3122835 bytes, checksum: 2a962c8596eae20801290e744716b2cf (MD5) Previous issue date: 2005
Resumo: Neste presente trabalho, foi estudada a grafitização de N-metilol acrilamida em amido de mandioca nativo, em meio aquoso, com proporções de 20, 30 e 40% em relação ao peso de amido, tendo como objetivo avaliar a aplicação técnica do produto resultante em formulações de tintas de revestimentos couché, aplicado sobre uma superficie de papel cartão. Estes novos polímeros, bem como o amido de mandioca e o amido de milho nativo, foram caracterizados por: (i) Análise Dinâmico-Mecânica (DMA), onde se conseguiu verificar moderadas modificações nas transições térmicas; (ii) Espectroscopia na região do Infravermelho(FT_IR); (iii) Microscopia Ótica (MO) e (iv) Microscopia Eletrônica de Varredura (MEV), onde percebeu-se mudanças morfológicas nos grânulos de amido modificado, que se apresentaram maiores que os do amido nativo. Para uma análise do comportamento destes polímeros em formulações de tintas de revestimentos couché, foi utilizado como referência padrão o látex de estireno-butadieno carboxilado, atualmente utilizado na indústria de papel, como ligante (ou resina) principal. Nas tintas de revestimentos couché desta tese, foram analisadas as aplicações feitas em papel cartão revestido, onde se utilizou para teste de imprimibilidade as seguintes análises: Pick teste seco; Pick teste úmido; alvura; teste de absorção superficial - K & N; brilho de impressão; rugosidade e absorção de óleo. Um bom revestimento deverá apresentar uma boa adesão à superficie do papel, evitando seu arrancamento do mesmo. Dos testes de arrancamento, todas as amostras dos revestimentos feitos com amido de mandioca, modificados com Nmetilol acrilamida, apresentaram excelentes resultados
Abstract: In this work, it was studied the graftization of native tapioca starch with of Nmethylol acrylamide (NMA) in aqueous media, at several proportions (20, 30 e 40%) relative to the starch weight, with the aim to evaluate the technical application of the product obtained in inks formulations used for finishing covering, applied over paper-card surfaces. The NMA and the native starch, as well as the starch derivatives, were characterized by: (i) Dynamic Mechanical Analysis (DMA), which showed mild modifications in the thermal transitions; (ii) lnfrared Spectroscopy (F_TIR); (iii) Oplical Microscopy (OM) and (iv) Electron Scanning Microscopy (SEM) which revealed morphological changes in the starch grains, being the modified starch grains bigger than those native. To analyze the behavior of these polymers in formulations of inks, used for finishing covering (known as couché paper card), it was utilized latex of styrene-butadiene - carboxylate as reference, current1yused as binder in the paper industry. For the paper card with the finishing covering it was utilized tests of printability as: dry pick test; wet pick test; whiteness; K and N test; shine of impression; roughness and oil absorption. In the printing process, the graphic ink used presents tacking that is responsible for a perpendicular force to the surface of the paper, which is able to peel its covering. The peeling tests done with the formulations modified with modified tapioca starch with Nmethylol acrylamide (NMA) presented very promising results
Mestrado
Ciencia e Tecnologia de Materiais
Mestre em Engenharia Química

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Kjellgren, Henrik. "Influence of paper properties and polymer coatings on barrier properties of greaseproof paper." Doctoral thesis, Karlstad : Faculty of Technology and Science, Chemical Engineering, Karlstads universitet, 2007. http://www.diva-portal.org/kau/abstract.xsql?dbid=1238.

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Wilke, Caroline. "Fördröja åldrandet av elektrotekniskt papper genom kemikalietillsats : En studie av dicyandiamids påverkan." Thesis, Karlstads universitet, Fakulteten för teknik- och naturvetenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-7357.

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Nordic Paper Åmotfors tillverkar elektrotekniskt papper som används till att isolera lindningarna i transformatorer. Det är viktigt att bibehålla papprets egenskaper under en mycket lång tid då en transformators livlängd är lång. Syftet med detta examensarbete var att undersöka huruvida tillsats av en kemikalie bestående av dicyandiamid kan fördröja åldrandet av de papper som Nordic Paper tillverkar. Förhoppningen var att deras papper därefter skulle klara de krav-parametrar som finns för papper som åldrats i olja. Kemikalien som användes var Cartafix® WE liquid. Försök utfördes där olika kemikaliedoseringar tillsattes i mälden. Pappersark tillverkades och kvävehalten mättes därefter för att verifiera att kemikalien fastnat i de färdiga papprena. Pappers-arken åldrades sedan endera i olja eller i luft, och den kvarvarande polymerisationsgraden (DP) mättes. Sprängstyrke- och konduktivitetstester utfördes också. Papper som Nordic Paper tillverkat beströks med olika kemikaliedoseringar och samma tester utfördes även på dessa. Resultaten visade att retentionen av kemikalien var låg. Kvävehalten blev inte högre än 1 % och detta skedde vid 10-20 % kemikalietillsats. Efter åldring i olja minskade DP relativt mycket, vilket medförde att papprena inte uppnådde de uppsatta kraven (maximalt 50 % minskning). Tillsats av kemikalien förbättrade dock papprets åldringsegenskaper med nästan 45 % om icke-modifierat papper jämförs med det modifierade pappret som hade högst DP (10 % kemikalietillsats, vilket motsvarade 1 % kvävehalt). Papper som modifierats med kemikalietillsats i mälden gav lägre DP då åldringen skett i luft jämfört med icke-modifierat papper. DP minskade avsevärt efter åldring för papper som bestrukits med kemikalien. Kemikalietillsats försämrade både sprängstyrkan och konduktivteten.
Nordic Paper Åmotfors manufactures electro technical paper that is used to isolate the windings in transformers. It is important to maintain the properties of the paper during a long period of time because the life of a transformer is extensive. The purpose of this thesis was to investigate whether or not addition by a chemical consisting of dicyandiamide could delay the ageing of the papers that Nordic Paper manufactures. The aspiration was that their paper would then fulfil the requirements that are applicable to papers that have been aged in oil. The chemical that was utilised is called Cartafix® WE liquid. Experiments were conducted where different dosages of the chemical were added to the stock. Sheets of paper were manufactured and the nitrogen level was then measured in order to verify that the chemical had been fused in the finished paper. The paper sheets were then aged in either oil or air and the remaining degree of polymerisation was measured. Bursting strength and conductivity were also evaluated. Papers that Nordic Paper had manufactured were coated with different dosages of the chemical and then investigated in the same manner. The results showed that the retention of the chemical was relatively low. The nitrogen level did not exceed 1 %, which occurred at 10-20 % addition of the chemical. After ageing in oil, the degree of polymerisation was significantly reduced, which meant that the papers did not fulfil the requirement of a maximum of 50 % reduction. The addition of the chemical did however improve the ageing resistance with nearly 45 % if the unmodified paper is compared to the modified paper with the highest degree of polymerisation (10 % addition, equivalent to 1 % nitrogen). Papers that had been modified by addition of chemicals in the stock and had been aged in air exhibited lower degree of polymerisation than unmodified paper. The degree of polymerisation was significantly reduced for papers that had been coated and aged in air. Addition of chemicals resulted in both lower bursting strength and lower conductivity.

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Hjort, Mikael. "Solar Powered Paper Drying in Bangladesh : A feasibility study on using a solar thermalenergy to dry handmade paper in Bangladesh." Thesis, Uppsala universitet, Fasta tillståndets fysik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-210903.

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Solar energy has a great potential to give cheap and abundant energy to rural areas of the world, but is the technology ready to be implemented today? This stydy looked at the possibilities to introduce more renewable energy into the local hand-made paper production in Bangladesh. Specifically the potential of solar heated vacuum tubes filled with water as a heat carrier. This type of solar thermal collectors are cheap to produce, relatively efficient at converting both direct and diffuse solar energy into usable energy, and have a very simple construction that do not require a lot of training to handle. The study showed that the collector could convert about 70 % of the energy from the sun into usable energy in the form of hot water circulated in the system. On average in Bangladesh the 5 m2 collector used is expected to have an output of about 25.6 MJ per day (yearly average) and about 4.8 MJ was needed to evaporate 1 kg of water from the drying papers (including the system losses). This can be compared with the old system that used about 8 MJ per kg water evaporated. Finally the study includes a step by step guide into how to build a system like this by locally available material. The only parts that were imported were some measurement equipment and parts of the collector that was not yet available through local distributors. The pump was also not produced in Bangladesh, but a similar pump could be bought by local companies that import this type of equipment.

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Schreck, Camille. "Interactive deformation of virtual paper." Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAM048/document.

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Le papier est un matériau très commun que l'on manipule quotidiennement. Pourtant on ne le trouve que rarement dans les environnements 3d. En effet, à cause de sa structure fibreuse, le papier, de même que le son qu'il produit, présente un comportement complexe qui se révèle difficile à reproduire avec les méthodes habituelles. En particulier, la surface du papier reste constamment isométrique à son patron 2D et peut se froisser ou se déchirer, créant ainsi de fins détails géométriques. Lorsqu’il se déforme, le papier produit également un son très caractéristique qui dépend fortement de la géométrie adoptée par la surface.Dans cette thèse, nous proposons de combiner une simulation physique usuelle avec de nouvelles méthodes, procédurales ou géométriques, de façon à tirer parti de connaissances préalables afin de modéliser la surface et le son d'une feuille de papier manipulée virtuellement. Plutôt que d'obtenir des résultats précis au sens physique, nous cherchons à reproduire un comportement plausible du papier, permettant ainsi à un utilisateur de créer interactivement des animations de papier virtuel.Nous nous concentrons dans un premier temps sur le cas du papier froissé. Pour cela, nous entrelaçons une étape de simulation physique avec une étape de remaillage géométrique qui adapte le maillage aux plis du papier froissé, exploitant pour cela la dévelopabilité du papier.Nous tirons ensuite profit de ce modèle pour développer une méthode permettant de déchirer du papier virtuelle en temps réel. Nous utilisons les informations sur la géométrie fournie par l'étape de remaillage pour trouver les points pouvant potentiellement être les points de départ d'une déchirure. Nous proposons aussi une nouvelle approche hybride, à la fois physique et géométrique, pour déterminer la direction général de propagation tout en créant de façon procédurale les détails du tracé d'une déchirure en utilisant une texture représentant la répartition des fibres.Enfin, nous proposons une génération de sons de papier, à la fois plausible, dépendant de la forme de la surface et qui s'opère en temps réel. Nous analysons les informations, géométriques et dynamiques, données par le modèle d'animation pour détecter les événements produisant du son et calculer les régions dans lesquelles le son résonne. Le son résultant est synthétisé à l'aide de sons pré-enregistrés et d'une génération procédurale, de façon à tenir compte de géométrie de la surface et sa dynamique
Although paper is a very common material in our every-day life, it can hardly be found in 3d virtual environments. Indeed, due to its fibrous structure, paper material exhibits complex deformations and sound behaviour which are hard to reproduce efficiently using standard methods. Most notably, the deforming surface of a sheet of paper paper is constantly isometric to its 2D pattern, and may be crumpled or torn leading to sharp and fine geometrical features. During deformation, paper material also has very characteristic sound, which highly depends on its complex shape.In this thesis, we propose to combine usual physics-based simulation with new procedural, geometric methods in order to take advantage of prior knowledge to efficiently model the geometry and the sound of a deforming sheet of paper. Our goals are to reproduce a plausible behaviour of paper rather than an entirely physically accurate in order to enable a user to interactively deform and create animation of virtual paper.We first focus on the case of paper being crumpled. We use the developability property of the paper to interleave the physics-based simulation with a geometric remeshing step that adapts the mesh with the fold and the sharp creases of crumpling paper. We obtain an interactive model able to reproduce the main features of crumpling paper.We then take advantages of this model to develop of method for tearing paper in real-time. We use the geometric information provided by the remeshing step of the model to detect potential starting points of tears, and propose a new hybrid, geometric and physical, method to find their general direction of propagation while creating procedurally the details of the tearing path using a fibres' texture.Finally, we propose to generate a plausible shape-dependant sound of the paper at run-time. We analyse the geometric and dynamic information provided by the model to detect sound-producing events and compute the regions in which the sound resonate. The resulting sound is synthesized from both pre-recorded sounds and procedural generation taking into account the geometry of the surface and its dynamics

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Yasumura, Patrícia Kaji. "Caracterização de propriedades de papel para impressão por jato de tinta." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-06062013-170116/.

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Os novos processos de impressão têm exigido novas características do papel. Entre os novos processos encontram-se as impressões digitais, em especial, a impressão por jato de tinta. Este tipo de impressão é baseado na ejeção de uma gota de tinta por um orifício em uma cabeça de impressão, que atinge o substrato formando um pixel. A definição das imagens formadas neste tipo de impressão é, portanto, dependente das características da tinta e, principalmente, do substrato. O presente trabalho tem por objetivo caracterizar as propriedades do papel que são importantes para a impressão por jato de tinta, desde o momento em que a tinta atinge a superfície do papel até a sua absorção. As propriedades consideradas neste estudo foram: a rugosidade, a porosidade e as propriedades químicas da superfície. A rugosidade foi avaliada pelos métodos tradicionais da área de papel e celulose (baseados em vazão de ar), por método perfilométrico e, qualitativamente, por imagens obtidas por microscopia eletrônica de varredura (MEV). Para a porosidade foi utilizado um método tradicional, além de porosimetria de intrusão de mercúrio e microtomografia de raios X, e a composição química da superfície foi avaliada por espectroscopia por energia dispersiva (EDS) e espectroscopia Raman. A partir dos resultados obtidos, as propriedades do papel foram qualificadas e as suas influências no espalhamento e absorção de líquidos em geral foram identificadas. Além da caracterização das propriedades superficiais e porosimétricas do papel, as correlações entre as propriedades e os diferentes métodos utilizados na sua determinação foram discutidas. Os métodos de análise tradicional não conseguem caracterizar os papéis em níveis de resolução capazes de fornecer informações sobre a influência das propriedades estudadas na impressão por jato de tinta. Ao mesmo tempo, a caracterização do papel para este tipo de impressão e a compreensão das influências das propriedades do papel no espalhamento e absorção de tinta e líquidos em geral só é possível quando as propriedades são analisadas em conjunto.
The new printing processes have required new features of the paper. Among the new printing processes are the digital printing, in particular, the inkjet printing. This type of printing is based on the ejection of an ink drop through a hole in a print head, which reaches the substrate forming a pixel. The resolution of the images formed in this type of printing is therefore dependent on the characteristics of the ink, and especially of the substrate. The present work aims to characterize the properties of paper that are important to the inkjet printing, from the moment the ink hits the paper surface to its absorption. The properties considered in this study were: roughness, porosity and chemical properties of the surface. The roughness was evaluated by traditional methods in pulp and paper sector (based on air flow), by profilometry and qualitative using images obtained by scanning electron microscopy (SEM). For the porosity, a traditional method was used, and also mercury intrusion porosimetry and X-ray microtomography. The chemical composition of the surface was evaluated by energy dispersive spectroscopy (EDS) and Raman spectroscopy. From the results obtained, the paper properties were described and their influence on the spreading and absorption of liquids in general have been identified. Besides the characterization of the paper surface properties and porosity, the correlations between the properties and the different methods used for measurement were discussed. The traditional analysis methods can not characterize the paper in levels of resolution capable of providing information about the influence of the properties studied in inkjet printing. At the same time, to characterize paper for this printing process and to understand the influences of the paper properties on the spreading and absorption of inks and liquids in general the paper properties have to be analyzed together.

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Jain, Amitkumar Champalal. "Moisture transport in paper and paper coatings /." Philadelphia, Pa. : Drexel University, 2004. http://dspace.library.drexel.edu/handle/1860/354.

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Santhiago, Murilo 1984. "Construção e aplicação de dispositivos analíticos 2D e 3D à base de papel com detecção eletroquímica." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248388.

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Orientador: Lauro Tatsuo Kubota
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica
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Resumo: Neste trabalho descreve-se a construção e aplicação de dispositivos analíticos 2D e 3D à base de papel com detecção eletroquímica (ePAD). Os dispositivos foram construídos empregando o método de impressão com cera e diferentes tipos de papéis. Eletrodos de ouro foram utilizados juntamente com o conceito da separação cromatográfica em dispositivos microfluídicos. No canal microfluídico à base de papel foi possível realizar a separação de ácido ascórbico e dopamina em 14 minutos. A necessidade por processos de fabricação mais simples e de baixo custo nos motivou a estudar eletrodos de carbono em ePADs. Assim, eletrodos de grafite de lapiseira foram selecionados visando o desenvolvimento de um biossensor para glicose. O biossensor apresentou uma excelente resposta eletroquímica e um tempo de análise de 4 minutos. O mesmo eletrodo de grafite foi acoplado com um sistema de informação para determinação de p-nitrofenol. Assim, foi possível detectar 1,0 mmol L de p-nitrofenol em amostras de água e analisar/interpretar os resultados empregando um celular. Por fim, a necessidade por sistemas eletroquímicos com menores limites de detecção nos impulsionou a fabricar microeletrodos de pasta de carbono. Os microeletrodos foram fabricados em folhas de transparência e acoplados no papel empregando uma configuração do tipo sanduíche. Os dispositivos foram caracterizados eletroquimicamente na presença de cisteína e apresentaram uma constante cinética de 10 L mol s. Um limite de detecção de 4,8 mmol L para cisteína foi obtido empregando um arranjo de microeletrodos. Por fim, os microeletrodos de pasta de carbono foram utilizados para a construção de um biossensor visando a determinação de metil paration. O ePAD foi construído de modo a acomodar o substrato (acetiltiocolina) e a enzima (acetilcolinesterase) no mesmo dispositivo
Abstract: This thesis describes the construction and application of 2D and 3D electrochemical paper-based analytical devices (ePADs). The devices were constructed using the wax printing method and different types of papers. Gold electrodes were employed along with the concept of chromatographic separation in microfluidic devices. By using the paper-based microfluidic channel it was possible to perform the separation of ascorbic acid and dopamine in 14 minutes. The need for simpler and low cost manufacturing processes motivated us to study carbon electrodes in ePADs. Thus, pencil graphite electrodes were selected for the development of a biosensor for glucose. The biosensor exhibited excellent electrochemical response and analysis time of 4 minutes. The same graphite electrode was coupled to an information system for the determination of p-nitrophenol. Thus, it was possible to detect 1.0 mmol L of p-nitrophenol in water samples and analyze/interpret the results using a smartphone. Finally, the need for electrochemical systems with lower limits of detection made us to search for carbon paste microelectrodes. The microelectrodes were fabricated on transparency sheets and coupled on paper using a sandwich-type configuration. The devices were characterized electrochemically in the presence of cysteine and had a rate constant of 10 L mol s. A detection limit of 4.8 mmol L for cysteine was obtained using an array of microelectrodes. By last, carbon paste microelectrodes were used to construct a biosensor in order to determine methyl parathion. The ePAD was constructed to accommodate the substrate (acetylthiocholine ) and enzyme ( acetylcholinesterase ) in the same device
Doutorado
Quimica Analitica
Doutor em Ciências

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Castro, Yong José Ignacio, Achic Mariana Elizabeth Chicchón, Neyra Jorge Luis Muñoz, Paredes Yomira Amada Vilela, and Aquino Anggelina Kaddy Yapuchura. "Paper Clean." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2020. http://hdl.handle.net/10757/654782.

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Debido a los sucesos que contrajo la pandemia del Covid-19 en nuestro país, se incrementó la demanda de productos de limpieza de higiene como jabones y gel antibacteriales para generar protección ante un posible contagio de este virus. Según datos reportados el sector que tuvo un mayor incremento en ventas fue el de limpieza. Dentro de este sector se encuentra Paper Clean, el cual, es un proyecto de negocio que tiene como propósito brindar un producto de limpieza de manos, tal como son las láminas de jabón que tiene como características ser antibacterial, con insumos naturales, variedad de aromas, innovador, con calidad e higiénico. Asimismo, nuestros jabones en láminas estarán enfocados a Mujeres del sector A y B dentro de Lima moderna.  Este proyecto surge con la finalidad de poder brindar a nuestro público un producto de calidad, diferente y que tenga un valor agregado para poder diferenciarnos del resto del mercado y que a la vez le genere bienestar y seguridad a nuestro público al usar nuestro producto. Este proyecto expone un análisis de los retos que conlleva participar en un mercado altamente competitivo y que nos obliga a diferenciarnos de la competencia, como también cómo emplearemos nuestras estrategias de operación, publicidad y se mostrará que el proyecto es viable lo que debe ser avalado por nuestros análisis financieros.
Due to the events of the Covid-19 pandemic in our country, the demand for hygiene cleaning products such as antibacterial soaps and gel was increased to generate protection against possible contagion of this virus. According to reported data the sector that had the greatest increase in sales was the cleaning. Within this sector is Paper Clean, which is a business project that aims to provide a hand cleaning product, such as soap sheets, which has the characteristics of being antibacterial, with natural inputs, a variety of aromas, innovative, with quality and hygienic. In addition, our foil soaps will be focused on Women from sector B within modern Lima. This project arises in order to be able to provide our audience with a quality product, different and that has added value to be able to differentiate us from the rest of the market and that at the same time generates well-being and safety to our public when using our product. This project sets out an analysis of the challenges of participating in a highly competitive market that forces us to differentiate ourselves from competition, as well as how we will use our trading strategies, advertising and show that the project is viable which should be endorsed by our financial analyses.
Trabajo de investigación

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Kholodko, S. G. "Paper clip." Thesis, Сумський державний університет, 2014. http://essuir.sumdu.edu.ua/handle/123456789/34864.

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Sometimes, coming to work every day and using familiar objects, we do not even think that in the cup with stationery items is a tiny and unique thing glorious with its long, interesting and controversial history. A paper clip is an instrument used to hold sheets of paper together, usually made of steel wire bent to a looped shape. Recent innovations include multi-colored plastic-coated paper clips and spring-fastened binder clips. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/34864

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Золотова, Світлана Григорівна, Светлана Григорьевна Золотова, Svitlana Hryhorivna Zolotova, and D. V. Shapko. "Electronic paper." Thesis, Видавництво СумДУ, 2010. http://essuir.sumdu.edu.ua/handle/123456789/18406.

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Mikovčáková, Michaela. "Paper biotope." Master's thesis, Vysoké učení technické v Brně. Fakulta výtvarných umění, 2011. http://www.nusl.cz/ntk/nusl-232301.

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Horský, Jakub. "Indie paper." Master's thesis, Vysoké učení technické v Brně. Fakulta výtvarných umění, 2013. http://www.nusl.cz/ntk/nusl-232373.

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Gardner, Edward. "Paper Tricks." VCU Scholars Compass, 2009. http://scholarscompass.vcu.edu/etd/1777.

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VILELA, Antonio Carlos. "Avalia??o dos fatores da perda de competitividade das empresas brasileiras de pap?is de impress?o revestidos: o couch?" Universidade Federal Rural do Rio de Janeiro, 2009. https://tede.ufrrj.br/jspui/handle/tede/1010.

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This study has had as objective, the identification of the main factors responsible for the loss of competitiveness in the Brazilian?s printing and coated industry. Coated wood free. For this identification was applied a strategy of data evaluation through structured interviews with four professionals with experience in the Paper Sector. It was used information issued in articles, magazines, dissertations, newspapers and on top of that primary and secondary data from the Pulp and Paper Sector were used, specifically the coated wood free for printing segment. The study had as assumption that there was loss of competitiveness in the Brazilian market, and the main factor responsible for this loss could be attributed to a systemic factor, the exchange rate. There was an increase of importation and reduction of exportation in the period of the study. The main factors identified in the interviews in sequence of importance and according to the interviewers were; exchange rate, the illegal usage of duty free operation during the importation and the lack of update the industrial equipments in the Brazilian Mills The currency, as a main factor of competitiveness loss for the Coated paper sector and it was confirmed through the evaluation of secondary figures of importation grow and exportation reduction in the period of 2003 till 2008. Other factor, the illegal usage of duty free operation during the importation, was based only in the perception of the interviewers; there were no dada available due to the subjectivity of this topic. The third factor, the lack of update the industrial equipments in the Brazilian Mills appointed during the interviews. It could be confirmed in the analyze of the world?s fastest paper machines and more competitive in the world in comparison with Brazilian?s paper machines which speed are very far from the more competitive machines in the world. The Brazil is not even mentioned in this article of machines caparison. When the factors that determine the competitiveness of printing coated papers are analyzed in group, the conclusion is that Brazil is not competitive in this segment due to several business factors. The currency that is a systemic factor and appears in the periods of currency valuation works in the process of exposure of the low competitiveness already existent.
Este trabalho teve como objetivo identificar os principais fatores que levaram a ind?stria brasileira de papel de imprimir revestido, o Couch?, ? perda de competitividade. Para identifica??o desses fatores foi aplicada a estrat?gia de an?lise de dados atrav?s da realiza??o de entrevista estruturada com quatro profissionais experientes ligados ao setor de pap?is, informa??es publicadas em artigos, revistas, teses e disserta??es, alem dos dados prim?rios e secund?rios do setor de celulose e papel, especificamente os do segmento do papel de imprimir revestidos ? o Couch?. Dentro deste objetivo foi adotada a suposi??o de que houve perda de competitividade no mercado brasileiro, e que um dos principais fatores da perda desta competitividade poderia ser atribu?do a um fator sist?mico, o cambio, havendo aumento das importa??es e redu??o das exporta??es no per?odo estudado. Os principais fatores identificados nas entrevistas, por ordem de import?ncia e segundo os entrevistados, foram: o cambio, a pr?tica desleal de isen??o tribut?ria e a falta de atualiza??o do parque industrial brasileiro. O cambio, como principal fator de perda de competitividade do setor de pap?is revestidos, pode ser corroborado atrav?s da an?lise dos dados secund?rios de importa??o crescente e exporta??o declinante no per?odo analisado de 2003 a 2008. O outro fator de pr?tica desleal da isen??o tribut?ria ficou apenas na percep??o dos entrevistados, n?o havendo dados dispon?veis para sua avalia??o pelo pr?prio grau de subjetividade deste tema. O terceiro fator de perda de competitividade apontado nas entrevistas foi a falta de atualiza??o do parque industrial brasileiro. Isto pode ser confirmado pela an?lise dos dados das m?quinas de papel mais velozes e competitivas do mundo em compara??o com as do Brasil, cujas velocidades est?o muito aqu?m das mais competitivas do mundo. O Brasil n?o ? sequer citado no artigo comparativo. Quando os fatores determinantes da competitividade dos pap?is de imprimir revestidos s?o analisados em conjunto, observa-se que o Brasil n?o ? competitivo neste segmento devido a diversos fatores empresarias. Quando a quest?o cambial, que ? um fator sist?mico, aparece em per?odos de valoriza??o cambial, este somente exp?e e agrava mais ainda esta baixa competitividade existente.

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Khan, Kashif. "Development and evaluation of a puncture strength test method for sterilization paper." Thesis, Karlstads universitet, Avdelningen för kemiteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-8585.

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The main objective of this research project, carried out at Karlstad University was to investigate which paper property has the best correlation with the package integrity failure (puncture hole). To achieve this goal, a simple equipment was designed at Karlstad University. This research project was divided into two phases, more precisely first a test design with investigation of suitable parameters to carry out the tests with the newly designed equipment and secondly with the help of those parameters the investigation of paper properties which will have direct connection with puncture strength. Results showed that Tensile Energy Absorption (TEA) has the best correlation with puncture strength as compared to other paper properties used in this research project i.e. burst strength, strain at break, tear strength, and tensile strength. In real it seems to be reasonable as tensile energy absorption (TEA) is the amount of energy absorbed during straining until it breaks. Higher the tensile energy absorption, higher will be the resistance against puncture. Furthermore sack paper proved to be the type of paper grade that has the strongest resistance against package integrity failure, as it has the highest tensile energy absorption (TEA) as compared to other paper grades used in this research project. It was also observed that paper in a package should be stretched in order to minimize the risk of puncture hole.

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Dimetry, Basant Galal. "The Relationship between Rheology, Application Method, and Final Coating Structure." Fogler Library, University of Maine, 2001. http://www.library.umaine.edu/theses/pdf/DimetryBG2001.pdf.

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Qi, Jie Ph D. Massachusetts Institute of Technology. "Paper electronics : circuits on paper for learning and self-expression." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/109617.

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Thesis: Ph. D., Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2016.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
"September 2016." Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 148-156).
In this dissertation, I explore the theme of wonder in technology, learning and self-expression through the lens of paper electronics, which is circuit building on paper using conductive tapes and circuit components as electronic craft materials. This new medium blends the interactive functionality of electronics with the expressive flexibility of the paper medium. I present an overview of the paper electronics medium as well as its extension in the form of electrified books, books with circuitry integrated with its pages and spine. I then described the design of a paper electronics toolkit called circuit stickers and how this toolkit was deployed through a company called Chibitronics. Finally, through the circuit stickers toolkit, I investigate and evaluate the paper electronics medium as a learning tool and approach, expressive medium and method to engage more diverse communities in technology creation. These investigations show that paper electronics has indeed impacted learners, educators and creators across many backgrounds and disciplines. It has enabled educators to teach a broad range of subjects and skills in new ways. Artists have used paper electronics to explore electricity and interactivity for self-expression, demonstrating the aesthetic flexibility and expressive potency of this medium. Finally, it has engaged creators from diverse communities and backgrounds including educators, Makers, and crafters. It enables not only new approaches to learning and creating technology, it also engages new types of creators in inventing surprising technological artifacts--ones that inspire new experiences, objects and opportunities for wonder.
by Jie Qi.
Ph. D.

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Jeong, Laila S. (Laila Silvija) 1955. "Competitive advantage in the U.S. paper and paper products industry." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/9283.

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Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management, 2000.
Includes bibliographical references.
Many firms in the U.S. paper converting industry are engaged in the commodity business of manufacturing finished paperboard products from paper stock. Contrary to the typically held mindset, these firms do not have to be relegated to the low margin end of the business. This thesis applies the various dimensions of the Delta Model to the paper converting business of the Chesapeake Corporation to define a new competitive positioning that will attract, satisfy, and retain the firm's customers. The overall objective is to develop the key elements of a new business strategy for Chesapeake upon which the business strategic agenda can be built. A new business model for the firm is presented that is centered on the "Total Customer Solution" and "System Lock-In" options of the Delta Model. The future business scope created by this new competitive positioning is defined and discussed in terms of new products and services, market segments, geographic coverage, and unique corporate competencies. These factors are used to identify three initial market segments that provide Chesapeake important opportunities to offer added-value to customers. Specific value propositions by customer segment are presented. The intent of each value proposition is to engender deep customer relationships that ultimately make Chesapeake successful because its has enabled its immediate customer to serve its own customer in a superior way.
by Laila S. Jeong.
M.B.A.

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Ekholmer, Henrik. "Prediction and Optimization of Paper Quality Properties in Paper Manufacturing." Thesis, KTH, Optimeringslära och systemteori, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-200383.

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A problem in the paper industry is that most paper quality properties can only be measured in lab after a full tambour of paper is produced. The tambour length is normally about 20-40 km and takes about one hour to produce. This may lead to one hour production and several km of paper becomes wasted due to poor paper quality. To reduce this problem, prediction models can be used to estimate the paper quality properties on-line. By using these models, a control strategy can be developed, which make sure that the paper quality properties are fulﬁlled. Optimization has here been used to ﬁnd a control strategy that minimizes the cost to produce paper of with desired paper quality properties. In the thesis, focus has been to ﬁnd models for prediction of paper quality properties, which includes synchronizing data in diﬀerent parts of the paper machine and lab, variable selection and ﬁltering. Focus has also been on minimizing production cost, utilizing the models of paper quality properties. A sensitivity analysis has been done for a number of variables in order to increase the understanding of the optimization.
Ett stort problem inom pappersindustrin i dag är att de ﬂesta papperskvaliteter bara kan mätas i ett labb efter en hel tambur är producerad. En tamburs längd är ca 20-40 km och tar ungefär en timme att producera. Detta kan leda till att en hel timmes produktion och ﬂera kilometer av papper går till spillo på grund av dålig papperskvalitet. För att lösa detta kan en prediktionsmodell användas för att uppskatta papperskvaliteterna on-line. Med denna modell kan även en kostnadsoptimering utföras för att producera samma kvalitet men till ett lägre pris. I detta examensarbete ligger största fokus p å att välja en modell för att prediktera papperskvaliteterna. Detta inkluderar synkronisera data i olika delar av pappersmaskinen, variabelselektion och ﬁltrering. Nästa fokus är att optimera produktionskostnaderna baserat p å prediktionsmodellen. En känslighetsanalys utförs p å kostnaden för ett antal variabler för att öka förståelsen för modellen.

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Nielsen, Ingelise. "Dimensional stability of paper in relation to paper conservation procedures." Thesis, University of Manchester, 1994. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.674633.

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Todd, Robin Margot. "Paper, scissors, stone." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ31008.pdf.

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St, Clair Barbara. "Scissors paper rock." [Tampa, Fla] : University of South Florida, 2007. http://purl.fcla.edu/usf/dc/et/SFE0001896.

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Andres, Britta. "Paper-based Supercapacitors." Licentiate thesis, Mittuniversitetet, Avdelningen för naturvetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-22410.

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The growing market of mobile electronic devices, renewable off-grid energy sources and electric vehicles requires high-performance energy storage devices. Rechargeable batteries are usually the first choice due to their high energy density. However, supercapacitors have a higher power density and longer life-time compared to batteries. For some applications supercapacitors are more suitable than batteries. They can also be used to complement batteries in order to extend a battery's life-time. The use of supercapacitors is, however, still limited due to their high costs. Most commercially available supercapacitors contain expensive electrolytes and costly electrode materials. In this thesis I will present the concept of cost efficient, paper-based supercapacitors. The idea is to produce supercapacitors with low-cost, green materials and inexpensive production processes. We show that supercapacitor electrodes can be produced by coating graphite on paper. Roll-to-roll techniques known from the paper industry can be employed to facilitate an economic large-scale production. We investigated the influence of paper on the supercapacitor's performance and discussed its role as passive component. Furthermore, we used chemically reduced graphite oxide (CRGO) and a CRGO-gold nanoparticle composite to produce electrodes for supercapacitors. The highest specific capacitance was achieved with the CRGO-gold nanoparticle electrodes. However, materials produced by chemical synthesis and intercalation of nanoparticles are too costly for a large-scale production of inexpensive supercapacitor electrodes. Therefore, we introduced the idea of producing graphene and similar nano-sized materials in a high-pressure homogenizer. Layered materials like graphite can be exfoliated when subjected to high shear forces. In order to form mechanical stable electrodes, binders need to be added. Nanofibrillated cellulose (NFC) can be used as binder to improve the mechanical stability of the porous electrodes. Furthermore, NFC can be prepared in a high-pressure homogenizer and we aim to produce both NFC and graphene simultaneously to obtain a NFC-graphene composite. The addition of 10% NFC in ratio to the amount of graphite, increased the supercapacitor's capacitance, enhanced the dispersion stability of homogenized graphite and improved the mechanical stability of graphite electrodes in both dry and wet conditions. Scanning electron microscope images of the electrode's cross section revealed that NFC changed the internal structure of graphite electrodes depending on the type of graphite used. Thus, we discussed the influence of NFC and the electrode structure on the capacitance of supercapacitors.

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Ansari, Rushina. "Creative Paper Recycling." Thesis, Malmö högskola, Fakulteten för kultur och samhälle (KS), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-23795.

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With the intention of empowering children and guiding them towardssustainable habits at an early age, the empirical findings in the choseninternational school pointed towards a heavy use of paper. A study wascarried out to understand the various factors related to paper use.Interviews, experiments and workshops were conducted to probe furtherinto the variety of insights that were gathered.The scope of the project was to use interaction design techniques tounderstand and address the issues through creating small designinterventions using three main strategies of a) placing appropriateaffordances, b) designing for transparency and hence creating awarenessof the use of resources, and c) by attempting to instill a culture throughdirect involvement that supports eco-ethics.An effort was made to conceptualize and design an artifact that was inline with the mood and disposition of the specified section of the school. Ametaphorical concept prototype was created to test the effect of theproposed artifact. Moreover, the overall culture of the school affected thebehavioral patterns and hence a separate strategy was employed toaddress the awareness in the entire institution.

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warren, matthew t. "Ink on Paper." VCU Scholars Compass, 2016. http://scholarscompass.vcu.edu/etd/4166.

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This thesis establishes the sources and potential solutions for my fractured and often contentious relationship with photography. The anxieties of contemporary artists working with photographic vocabularies are manifest and the tools to consider and critique this work is evasive and lacking. This text is both support and companion to my exhibition.

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Howell, Caroline M. "Mosaic in paper /." Online version of thesis, 1987. http://hdl.handle.net/1850/10318.

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Tyler, William Aldon. "Dream. Paper. Feast. /." Available to subscribers only, 2009. http://proquest.umi.com/pqdweb?did=1796120871&sid=5&Fmt=2&clientId=1509&RQT=309&VName=PQD.

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Tyler, William. "Dream. Paper. Feast." OpenSIUC, 2009. https://opensiuc.lib.siu.edu/theses/438.

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Plášil, Ondřej. "Papír." Master's thesis, Vysoké učení technické v Brně. Fakulta výtvarných umění, 2019. http://www.nusl.cz/ntk/nusl-396097.

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The aim of this thesis is to create a portfolio of paper products with respect to established ethical principles. The resulting products must have a suitable design optimized for the manufacturing process. Based on the changes in sales over the past two decades, this work revises the current market position of paper. In addition, it generally examines the unethical communication of paper entities towards the end user. The result of this thesis is a range of products of two selected basic types - notebook and photo album. The overall results of my efforts, including this work, are likely to result in the creation of a new, own brand.

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Sananpanichkul, Wanna. "Paper and printed paper surface characteristics studied using an optical method." Thesis, Open University, 1993. http://oro.open.ac.uk/54812/.

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A non-contact optical method for evaluating surface characteristics is reviewed. The optical reflectance instrument has been improved to be able to evaluate printed surfaces. Experiments were conducted with solid prints prepared on two types of papers printed with a heatset yellow ink. Both paper surfaces and printed surfaces are characterized into two regions: above the surface plane resulting in macrosmoothness (Sm) and below the surface plane resulting in microsmoothness (Su). For a better understanding of such optical print smoothness, a printed surface model is proposed based on Barkas' classical model. It is generally known that the qualities of a print are determined by the materials and their interactions in the process, therefore the formation of printed surface characteristics has been discussed in relation to ink and paper interaction. Print smoothness is influenced by the uncompressed paper roughness and porosity, which determine the degree of ink penetration and ink distribution on the surface. Offset lithographic printing has been the most widely used printing process, printing onto paper substrates. To achieve good press performance and high quality prints, the ink has to emulsify a certain amount of fountain solution; maintenance of this ink and water balance is, therefore, very important. The effects of fountain solution emulsified in the ink on print smoothness wp-re investigated. A range, of varying amounts of fountain solutions, was emulsified in a heatset yellow ink using a high speed laboratory mixer; these 'emulsion inks' were printed as soon as possible after preparation. It was found that the print smoothness in macro regions, for both uncoated and coated papers, decreased significantly. In addition, an unpigmented ink system was employed to verify the role and the effects of pigment in the emulsification mechanism on print smoothness. The results indicated that pigment is the dominant contributor, to a smoothness decrease; and the pigment effect arises from the amount of fountain solution emulsified in the ink. It has become important to measure print quality directly and quantitatively in the developments of ink, paper and printing technologies. This method makes it possible to measure print smoothness as a criterion for print quality.

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Passos, Rafaela Fernanda Carvalhal. "Desenvolvimento de dispositivos eletroquímicos descartáveis para análises rápidas." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248392.

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Orientador: Lauro Tatsuo Kubota
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: Este trabalho apresenta o esforço dispendido na construção e caracterização de transdutores eletroquímicos sobre poliéster e papel, e também demonstra o emprego destas células eletroquímicas descartáveis no desenvolvimento de um biossensor para análises rápidas de salicilato em sangue, bem como a criação de um dispositivo de separação associado à detecção eletroquímica em papel. Cada célula eletroquímica é composta por um conjunto de três eletrodos de filmes finos construídos em ouro sobre poliéster ou papel cromatográfico por meio das técnicas de sputtering e electron-beam, respectivamente. Foi realizada a caracterização voltamétrica dos sistemas eletródicos empregando sondas redox como hexacianoferrato(II) de potássio, hexacianoferrato(III) de potássio e ácido ferrocenomonocarboxílico em meio eletrolítico, a fim de verificar a eletroatividade dos mesmos. Foi possível verificar que mesmo apresentando maior área eletroativa, os eletrodos de filmes finos construídos sobre papel apresentam uma menor densidade de corrente para as sondas redox em comparação com a célula eletroquímica construída em poliéster. Isto se deve à retenção das espécies eletroativas na fibra de celulose, fato que diminui a disponibilidade da espécie na superfície eletródica. Foi desenvolvido um biossensor amperométrico para a determinação de salicilato em sangue. O biossensor se baseia no emprego da enzima Salicilato hidroxilase imobilizada sobre a célula eletroquímica plástica. As condições experimentais otimizadas consistem em utilizar uma solução eletrolítica de tampão fosfato em pH 7,6 com 0,5 mmol L de NADH e 300 mV vs. Au como potencial aplicado durante as medidas. O biossensor apresentou adequada sensibilidade (97,4 nA/mmol L de salicilato) e faixa linear de resposta para o analito (1,25 10 to 1,0 10 mol L). O desempenho do biossensor foi verificado na determinação de salicilato em amostras de sangue dopadas com o analito e os resultados foram estatisticamente equivalentes àqueles obtidos com o método espectrofotométrico de Trinder em um nível de confiança de 95%. O dispositivo de separação cromatográfica em papel associado à detecção eletroquímica foi desenvolvido empregando a célula eletroquímica plástica e a célula eletroquímica sobre papel. O desempenho dos dispositivos foi avaliado na separação e quantificação de ácido úrico e áscórbico presentes em mistura. O método desenvolvido é uma alternativa para a determinação de compostos eletroativos em que o baixo custo e a simplicidade são essenciais
Abstract: This paper presents the efforts to the construction and characterization of electrochemical transducers on polyester and paper, and also demonstrates the use of these disposable electrochemical cells in the development of a biosensor for rapid analysis of salicylate in blood as well as the creation of a separation device associated electrochemical detection on paper. Each electrochemical cell consists of a set of three electrodes made of gold thin films on polyester or chromatographic paper using sputtering and electron-beam techniques, respectively. The electrochemical characterization of the systems with redox probes as potassium hexacyanoferrate(II), potassium hexacyanoferrate(III) and ferrocene monocarboxylic acid was performed in the electrolyte solution in order to evaluate the electroactivity of them. It was verified that even with higher electroactive area, the electrodes of thin films built on paper have a lower current density for the redox probes in comparison with the electrochemical cell constructed on polyester. This is due to retention of electroactive species in the cellulose fiber, a fact that reduces the availability of those species on the transducer surface. We developed an amperometric biosensor for the determination of salicylate in blood. The biosensor is based on the use of the salicylate hydroxylase enzyme immobilized on plastic electrochemical cell. The determined optimized experimental conditions are: an electrolyte solution of phosphate buffer at pH 7.6 with 0.5 mmol L of NADH and 300 mV vs. Au as the applied potential during the measurements. The biosensor showed adequate sensitivity (97.4 nA / mmol L salicylate) and linear response range for the analyte (1.25 10 to 1.0 10 mol L). The performance of the biosensor was found in the determination of salicylate in blood samples spiked with the analyte and the results were statistically equivalent to those obtained with the Trinder¿s spectrophotometric method, with a 95% confidence level. Prototypes of microfluidic paper-based separation devices with amperometric detection were developed and evaluated. The chromatographic separation on paper associated with electrochemical detection was developed using the plastic electrochemical cell and the gold electrochemical cell on paper. The performance of both devices was evaluated for separation and quantification of uric acid and ascorbic acid presented in the mixtures. The method is an alternative for the determination of electroactive compounds when low cost and simplicity are essential
Doutorado
Quimica Analitica
Doutor em Ciências

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35

Devlin, Christopher P. "An investigation of the mechanism of high-intensity paper drying." Diss., Available online, Georgia Institute of Technology, 1986:, 1986. http://etd.gatech.edu/theses/available/ipstetd-8/devlin%5Fcp.pdf.

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López, González Néstor David. "Secagem convectiva de papel reciclado com incorporação de corantes naturais." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266710.

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Orientadores: Melissa Gurgel Adeodato Vieira, Sandra Cristina dos Santos Rocha
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: O papel está presente em muitas das atividades do cotidiano que vão desde usos sanitários, passando pelas embalagens até fins educativos. Este material que teve sua origem há quase 2000 anos, continua sua evolução na procura de alternativas limpas para seu reaproveitamento. Novos processos de reciclagem, secagem e a incorporação de materiais alternativos para melhorar as propriedades do papel fazem desta área de pesquisa a base para a criação de novas tecnologias e produtos com apelo ambiental. Neste contexto, este trabalho teve como objetivo a avaliação da reutilização de papel de escritório na forma de papel cartão com adição de extratos corantes naturais Carmim de cochonilha, Cúrcuma e Urucum, implementando um processo de destintagem dos papéis a serem reciclados e secando o papel em um secador convectivo em escala laboratorial para obter papel cartão artesanal colorido. Para isto, foi determinada uma formulação para cada uma das três polpas a serem tingidas com os corantes naturais e construídas as curvas de secagem para diferentes condições de secagem. Efetuou-se uma análise comparativa da qualidade dos papéis obtidos em diferentes condições de secagem e avaliou-se a degradação da cor dos papéis obtidos sob diferentes condições de iluminação. O estudo da secagem mostrou que as polpas fabricadas com cada um dos três corantes apresentaram processos de secagem equivalentes apesar de ter formulações diferentes. Além disso, uma análise estatística mostrou que a velocidade e a temperatura do ar de secagem influenciam positivamente o processo, afetando a duração deste. Na avaliação da qualidade dos papéis verificou-se que esta pode ser afetada por variações nas condições de secagem. Uma menor qualidade foi obtida em papéis secos sob condições mais drásticas de velocidade e temperatura do ar. Os testes de colorimetria realizados nas amostras evidenciaram que as condições de secagem podem modificar a saturação das cores dos papéis, gerando diferenças colorimétricas nos papéis obtidos e apresentando cinéticas de degradação diferentes para cada papel fabricado. Os extratos corantes de Carmim de cochonilha, Urucum e Cúrcuma apresentaram boa estabilidade no teste de abrigo à luz, mas nos testes realizados com luz ultravioleta e fluorescente a estabilidade das cores foi baixa. O carmim de cochonilha se apresentou como o corante com maior estabilidade e poder tintorial. Os corantes naturais analisados nesta pesquisa mostraram potencial para serem utilizados na fabricação de papéis reciclados artesanais
Abstract: The paper is present in many everyday activities from sanitary uses, through the packaging until educational purposes. This material was originated almost 2000 years ago, and continues its evolution in the search of environmental alternatives to be reused. New processes to recycling, drying and the incorporation of alternative materials carry out an important role for the creation of new products and new technologies with environmental appeal. In this context, this work aimed the evaluation of office paper in the form of cardboard with the addition of natural extracts dyes such as Cochineal Carmine, Turmeric and Annatto, using a de-inking process of paper and drying in a convective-scale laboratory dryer for obtain a colorful handmade paper card. For this, a formulation was determined for each of the three paper pulp to be dyed with natural dyes, the drying curves were analyzed for different drying conditions, moreover a comparative analysis of the quality of the paper obtained under different conditions of drying was accomplished and the degradation of color paper obtained under different lighting conditions was evaluated. The study showed that drying of the paper pulp manufactured for each of the three dyes present equivalent drying processes, despite that these had different formulations; in addition, a statistical analysis showed that the air velocity and temperature of the drying air have a positively influence in the process. In the study of quality of paper, it has been demonstrated that variations in the drying conditions affects the quality of paper, such as reducing these with the increase in velocity and air temperature. The colorimetric test showed that the drying conditions can change the color saturation of the paper, causing colorimetric differences in the papers obtained and having different degradation kinetics for each paper produced. The extracts of cochineal carmine, Annatto and Turmeric dyes showed good stability under the test of light; however, the stability for the test performed with ultraviolet and fluorescent light. The results using cochineal carmine dye presented greater stability and tinctorial power. Natural dyes tested in this study showed potential to be used in the manufacture of handmade recycled paper
Mestrado
Processos em Tecnologia Química
Mestre em Engenharia Química

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Gerdemark, Ida. "Papper! : En studie om materialet papper ur ett konsthantverksperspektiv." Thesis, Linköpings universitet, Estetiska avdelningen, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-93663.

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Denna studie syftar till att belysa papper som konsthantverksmaterial. Studien aktualiserar hur konsthantverkare som arbetar i papper beskriver sin relation till materialet och hur konsthantverkare som arbetar i papper upplever att deras val av material påverkar deras arbetssituation. Uppsatsen bygger på kvalitativa intervjuer med sex konsthantverkare som arbetar professionellt i Sverige med att på olika sätt skapa objekt i papper eller på olika sätt skapa materialet papper. Resultatet visar att konsthantverkare som arbetar i papper har en relation till materialet som genomsyras av trygghet, närhet, glädje och kontroll. Genom utbildning och/eller experiment har konsthantverkarna stärkt sin relation ytterligare till materialet. Pappret upplevs billigt, lättillgängligt och enkelt att bearbeta vilket medför att informanterna kan vara flexibla i deras arbeten och djupt utforska materialet. Papprets förgänglighet medför att konsthantverkarna kan uppleva det svårt att sälja sina produkter, men denna egenskap anses även korrelera med deras pappersprodukters avsedda funktion. Uttrycksmedlet papper har gett konsthantverkare en bättre arbetssituation än vad de tidigare upplevt när de till exempel tecknat eller målat då det innebär färre problem och ger fler idéer till gestaltning, de menar att pappret innehar stora möjligheter. I den nuvarande trenden som råder för pappershantverk, som bland annat kan ses på internet, kan arbeten i materialet bli särskilt uppmärksammade. Att arbeta med papper innebär också att konsthantverkarna ibland möter oförstående reaktioner från andra människor vad gäller materialet och den använda tekniken, vilket tyder på att föremål i papper normalt inte är särskilt vanligt och medför att de med tal behöver förklara sina arbeten. Arbetet i papper betyder även att konsthantverkarnas insats i form av tanke, kreativitet och tid blir viktig i det anspråkslösa materialet.

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Tinney, Brooke Merrill. "The effects of deinking on the coating compounds used on carbonless business forms /." Online version of thesis, 1991. http://hdl.handle.net/1850/11285.

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Liu, Chung-Ni. "Laboratory investigation of the effect of the dampening solution on the loss of surface strength of coated paper /." Online version of thesis, 1993. http://hdl.handle.net/1850/11983.

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Siqueira, Eder jose. "Polyamidoamine epichlorohydrin-based papers : mechanisms of wet strength development and paper repulping." Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00952991.

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Polyamideamine epichlorohydrin (PAE) resin is a water soluble additive and the most used permanent wet strength additive in alkaline conditions for preparing wet strengthened papers. In this thesis, we studied some properties of PAE resins and wet strengthened papers prepared from them. In order to elucidate PAE structure, liquid state, 1H and 13C NMR was performed and permitted signals assignment of PAE structure. PAE films were prepared to study cross-linking reactions and then thermal and ageing treatments were performed. According to our results, the main PAE cross-linking reaction occurs by a nucleophilic attack of N atoms in the PAE and/or polyamideamine structures forming 2-propanol bridges between PAE macromolecules. A secondary contribution of ester linkages to the PAE cross-linking was also observed. However, this reaction, which is thermally induced, only occurs under anhydrous conditions. The mechanism related to wet strength development of PAE-based papers was studied by using CMC as a model compound for cellulosic fibres and PAE-CMC interactions as a model for PAE-fibres interactions. Based on results from NMR and FTIR, we clearly showed that PAE react with CMC that is when carboxylic groups are present in great amounts. Consequently, as the number of carboxylic groups present in lignocellulosic fibres is considerably less important and the resulting formed ester bonds are hydrolysable, we postulate that ester bond formation has a negligible impact on the wet strength of PAE-based papers. In the second part of this work, a 100% Eucalyptus pulp suspension was used to prepare PAE-based papers. PAE was added at different dosages (0.4, 0.6 and 1%) into the pulp suspension and its adsorption was indirectly followed by measuring the zeta potential. Results indicate that the adsorption, reconformation and/or penetration phenomena reach an apparent equilibrium between 10 and 30 min. Moreover, we showed that the paper dry strength was not significantly affected by the conductivity level (from 100 to 3000 µS/cm) of the pulp suspension. However, the conductivity has an impact on the wet strength and this effect seems to be enhanced for the highest PAE dosage (1%). We also demonstrated that storing the treated paper under controlled conditions or boosting the PAE cross-linking with a thermal post-treatment does not necessarily lead to the same wet strength. Degrading studies of cross-linked PAE films showed that PAE degradation in a persulfate solution at alkaline medium was more effective. A preliminary study of industrial PAE-based papers (coated and uncoated papers) was also performed. For uncoated paper, persulfate treatment was the most efficient. For coated papers, all treatments were inefficient in the used conditions, although a decrease of the wet tensile force of degraded samples was observed. The main responsible of the decrease of persulfate efficiency for coated papers was probably related to side reactions of free radicals with the coating constituents.

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Siqueira, Eder José. "Polyamidoamine epichlorohydrin-based papers : mechanisms of wet strength development and paper repulping." Thesis, Grenoble, 2012. http://www.theses.fr/2012GRENI035/document.

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Le travail présenté dans ce manuscrit s’intéresse au mode d’action des résines thermodurcissables utilisées pour conférer au matériau papier des propriétés spécifiques. En effet, certains papiers sont destinés, au cours de leur usage, à être en contact avec des liquides et en particulier de l’eau. C’est le cas, par exemple, des papiers absorbants, de certains papiers filtres, mais aussi de papiers pour étiquettes ou pour billets de banque. En présence d’eau, les papiers perdent rapidement leur résistance mécanique, essentiellement due à la présence en grand nombre de liaisons hydrogène, d’où la nécessité d’un traitement : l’objectif est de maintenir un certain niveau de résistance des papiers saturés en eau. Ces traitements consistent à introduire dans la suspension fibreuse, en cours d’élaboration, des pré-polymères cationiques s’adsorbant à la surface des fibres. Après la formation de la feuille de papier, la feuille humide est séchée et c’est au cours de cette étape que s’amorce la réticulation de ces polymères. Elle conduit à la formation d’un réseau tridimensionnel de polymère dans le matelas fibreux. Ce réseau permet au papier de conserver ses propriétés mécaniques lorsqu’il est en contact avec de l’eau. Il présente ce que l’on appelle communément une résistance à l’état humide (REH). Un des inconvénients de ce type de traitement est lié aux difficultés de recyclage des papiers obtenus. Il nécessite un traitement particulièrement intensif et coûteux qui couple une action mécanique (désintégration, dépastillage) à une action chimique (utilisation d’hydroxyde de sodium, par exemple). Même si ces produits sont largement utilisés, les mécanismes mis en jeu que ce soit pour le développement des propriétés de REH ou pour le recyclage ne sont pas totalement compris. Dans ce contexte, ce travail a pour objectif d’étudier le mode d’action de pré-polymères de polyamideamine épichlorhydrine (PAE), couramment utilisés en papeterie pour conférer au matériau papier une résistance à l’état humide (REH). Il s’intéresse à la caractérisation de solutions commerciales de PAE et à l’étude des mécanismes réactionnels de ces pré-polymères. Il traite également de l’effet de certains paramètres de production du papier sur l’efficacité des traitements. Enfin, il apporte de éléments nouveaux sur la compréhension de l’étape de recyclage
Polyamideamine epichlorohydrin (PAE) resin is a water soluble additive and the most used permanent wet strength additive in alkaline conditions for preparing wet strengthened papers. In this thesis, we studied some properties of PAE resins and wet strengthened papers prepared from them. In order to elucidate PAE structure, liquid state, 1H and 13C NMR was performed and permitted signals assignment of PAE structure. PAE films were prepared to study cross-linking reactions and then thermal and ageing treatments were performed. According to our results, the main PAE cross-linking reaction occurs by a nucleophilic attack of N atoms in the PAE and/or polyamideamine structures forming 2-propanol bridges between PAE macromolecules. A secondary contribution of ester linkages to the PAE cross-linking was also observed. However, this reaction, which is thermally induced, only occurs under anhydrous conditions. The mechanism related to wet strength development of PAE-based papers was studied by using CMC as a model compound for cellulosic fibres and PAE-CMC interactions as a model for PAE-fibres interactions. Based on results from NMR and FTIR, we clearly showed that PAE react with CMC that is when carboxylic groups are present in great amounts. Consequently, as the number of carboxylic groups present in lignocellulosic fibres is considerably less important and the resulting formed ester bonds are hydrolysable, we postulate that ester bond formation has a negligible impact on the wet strength of PAE-based papers. In the second part of this work, a 100% Eucalyptus pulp suspension was used to prepare PAE-based papers. PAE was added at different dosages (0.4, 0.6 and 1%) into the pulp suspension and its adsorption was indirectly followed by measuring the zeta potential. Results indicate that the adsorption, reconformation and/or penetration phenomena reach an apparent equilibrium between 10 and 30 min. Moreover, we showed that the paper dry strength was not significantly affected by the conductivity level (from 100 to 3000 µS/cm) of the pulp suspension. However, the conductivity has an impact on the wet strength and this effect seems to be enhanced for the highest PAE dosage (1%). We also demonstrated that storing the treated paper under controlled conditions or boosting the PAE cross-linking with a thermal post-treatment does not necessarily lead to the same wet strength. Degrading studies of cross-linked PAE films showed that PAE degradation in a persulfate solution at alkaline medium was more effective. A preliminary study of industrial PAE-based papers (coated and uncoated papers) was also performed. For uncoated paper, persulfate treatment was the most efficient. For coated papers, all treatments were inefficient in the used conditions, although a decrease of the wet tensile force of degraded samples was observed. The main responsible of the decrease of persulfate efficiency for coated papers was probably related to side reactions of free radicals with the coating constituents

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42

Novell, Recasens Marta. "Paper-based potentiometric platforms for decentralised chemical analysis." Doctoral thesis, Universitat Rovira i Virgili, 2015. http://hdl.handle.net/10803/313994.

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En les darreres dècades, el món ha experimentat profunds canvis socials i tecnològics. Entre aquests, són destacables les tendències emergents d’anàlisis descentralitzats i de xarxes de sensors, que estan tenint un gran impacte en moltes àrees, especialment en el sistema sanitari. El desenvolupament d’eines per a realitzar anàlisis fora del laboratori de forma robusta, simple i econòmica, serà de gran ajuda per generar, per exemple, eines de diagnòstic assequibles. Per complementar aquestes tendències, aquesta tesis presenta el desenvolupament d’una eina analítica nova per anàlisis descentralitzats, usant paper modificat amb nanotubs de carboni com a substrat i la potenciometria com a tècnica de detecció. Els nanotubs de carboni s’han incorporat amb èxit sobre un paper de filtre convencional, convertint-lo així en conductor, i proporciona’t-li habilitat transductora ió-electró. Amb aquesta plataforma s’han desenvolupat elèctrodes selectius de ions per a diferents ions –mantenint el mateix rendiment analític que els elèctrodes convencionals- així com també un elèctrode de referència. La demostració de que aquesta plataforma pot solucionar un problema analític s’ha dut a terme a través del desenvolupament d’una cel·la potenciomètrica complerta de paper per a la detecció de liti en sang. Aquests elèctrodes també han estat combinats amb èxit amb un potenciòmetre d’identificació per radiofreqüència (RFID), cosa que permet el seu ús de forma descentralitzada. Altres aplicacions possibles, juntament amb les limitacions del sistema es discuteixen en detall. En definitiva, aquest treball obre la possibilitat de substituir sensors convencionals per aquesta plataforma més econòmica, obrint així tota una nova gama d’oportunitats.
En las últimas décadas, el mundo ha experimentado profundos cambios sociales y tecnológicos. Entre los cuáles son destacables las tendencias emergentes de análisis descentralizados y de redes de sensores, que tienen un gran impacto en muchas áreas, especialmente en el sistema sanitario. El desarrollo de herramientas para realizar análisis fuera del laboratorio de forma robusta, simple i económica, será de gran ayuda per generar, para generar, herramientas de diagnóstico asequibles. Para complementar estas tendencias, esta tesis presenta el desarrollo de una herramienta analítica nueva para análisis descentralizados, usando papel modificado con nanotubos de carbono como sustrato y la potenciometría como técnica de detección. Los nanotubos de carbono se han incorporado con éxito sobre un papel de filtro convencional, convirtiéndolo así en conductor, y proporcionándole habilidad transductora ion-electrón. Con esta plataforma se han desarrollado electrodos selectivos de iones para distintos iones manteniendo el mismo rendimiento analítico que los electrodos convencionales- así como también un electrodo de referencia. La demostración de que esta plataforma puede solucionar un problema analítico se ha hecho a través del desarrollo de una celda potenciométrica completa de papel para la detección de liti en sangre. Estos electrodos también se han combinado con éxito con un potenciómetro de identificación por radiofrecuencia (RFID), cosa que permite su uso de forma descentralizada. Otras aplicaciones posibles, junto con las limitaciones sistema se discuten en detalle. En definitiva, este trabajo abre la posibilidad de substituir los sensores convencionales por esta plataforma más económica, abriendo así tota una nueva gama de oportunidades.
During the last decades, the world has undergone deep social and technological changes. Remarkably are the emerging trends of decentralised analysis and sensing networks, which are having a deep impact in many areas, especially in the healthcare system. The development of tools for performing measurements out of the lab in a robust, simple and cost-effective way will be of great help to generate, for example, affordable diagnostic tools. To complement this trends, this thesis presents the development of a novel analytical tool for decentralised measurements, by using paper as a substrate modified with carbon nanotubes (CNT), and potentiometry as detection approach. CNTs have been successfully incorporated over a conventional filter paper making it conductive, and giving to it ion-to-electron transduction capability. Over this platform ion-selective electrodes for different ions have been developed –keeping the same analytical performance as conventional electrodes- as well as a reference electrode. The demonstration that this platform can solve an analytical problem has been proved through the development of a complete paper cell for the detection of lithium in blood. This electrodes have been also combined with a radio frequency identification (RFID) potentiometer, which will allows its use in a decentralised way. Other possible application of this platform together with its limitations are also discussed. All in all, this work opens the possibility to substitute conventional sensors for this low-cost paper sensors, thus unlocking a whole new range of possibilities.

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43

Lundmark, Robert. "Paper recovery and investment behaviour in the European pulp and paper industry." Licentiate thesis, Luleå tekniska universitet, Samhällsvetenskap, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-17295.

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This thesis consists of an introductory part followed by two self-contained papers both analysing the effect recovered paper has on the locational choice for investments in the European pulp and paper industry. In the first paper we develop a continuous Cobb-Douglas investment model with the purpose of finding and estimating the investment determinants for the European pulp and paper industry, with special focus on the impact of recovered paper. The analysis is carried out within a neo-classical locational framework in which firms minimise the production and transportation costs for both input factors and for output products. We use a panel of data consisting of ten European countries over the period 1978 to 1995. The results suggests that both short and long run aspects of wastepaper recovery tend not to be important determinants of investment activities in the pulp and paper industry, whereas the price of wood pulp and electricity together with existing capacity seem to be more important. In the second paper we employ a different approach to the same problem. In this paper we develop a conditional logit model and compile the number of investment projects that were scheduled to be finished in 16 European countries between 1985 and 1995. In contrast to the first paper, which used continuous data, this model employs discrete data for the dependent variable. A discrete variable counts the actual number of times a certain event has taken place, i.e., the number of investment projects. The same set of determinants as in the first paper is used to ease comparing the two papers. We further break down the investment projects into four paper grades, which allow us to analyse the effects of wastepaper in greater detail. The results suggest that factor input prices in general and the price for wastepaper in particular are neither statistically nor economically significant location determinants for a paper manufacturer. Furthermore, the results suggest that market size and agglomeration effects are more important than the price of raw materials for location. On the basis of the results from the two papers, we can conclude that the price of wastepaper is not an important determinant for the European pulp and paper industry when choosing investment sites. Price driven policies aimed at stimulating paper recovery may therefore fail to achieve increased investments in the industry. At the same time, both papers suggests that agglomeration effects, i.e., existing productive capacity, is an important determinant. The economic significance of the agglomeration coefficients suggests that the power of sunk costs is important. Investments are largely diverted to existing capacity and the ability to attract new establishments is limited.
Godkänd; 2000; 20070315 (keni)

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Åvitsland, Grete A. "Edgewise liquid penetration in paper : influence of surface chemistry and paper structure /." Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4082.

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Schafer, Robert. "Tropical island boundary layer structure and development /." [Sydney : University of Technology, Sydney], 1998. http://grison.colorado.edu/Robert/paper/phd.pdf.

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Vieira, Melissa Gurgel Adeodato 1979. "Analise da secagem de polpa de celulose para a obtenção de papel reciclado tipo cartão." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266275.

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Orientador: Sandra Cristina dos Santos Rocha
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
Made available in DSpace on 2018-08-06T13:17:18Z (GMT). No. of bitstreams: 1 Vieira_MelissaGurgelAdeodato_D.pdf: 15789035 bytes, checksum: a4310c5dbe44a9a8965201da94b3f2d8 (MD5) Previous issue date: 2006
Resumo: o papel ainda desempenha um fator chave na cultura e na difusão da informação apesar dos grandes avanços tecnológicos. Embora seja produzido a partir de um recurso renovável, como é a madeira, existe tecnologia que permite a sua reutilização a partir de fibras recuperadas. A recic1agem do papel permite uma grande redução na quantidade de resíduos sólidos urbanos, evitando a utilização de recursos naturais tais como a madeira e a água, além de diminuir bastante o consumo energético na indústria papeleira. A produção da polpa de celulose é o grande consumidor de energia no processo de fabricação do papel, seguido da secagem do papel, que é o segundo processo neste tipo de indústria que mais consome energia. A secagem é um processo complexo, de grande importância tanto em termos energéticos como também na qualidade do produto final. Neste contexto, este trabalho teve como proposta analisar a secagem de polpa de celulose a partir de fibras recuperadas para a fabricação de papel cartão recic1ado. Para tanto, projetou-se um secador convectivo, em escala laboratorial, para a secagem da polpa de papel. Foram determinadas as curvas de secagem em função de diferentes condições operacionais e as isotermas de dessorção do papel pelo método dinâmico. Uma análise da qualidade do produto foi realizada para as diferentes condições, além da análise energética do processo. Paralelamente, fez-se um estudo comparativo entre a secagem natural ao ar livre (utilizada em pequenas produções) e a secagem .por convecção forçada no secador projetado. Complementando o estudo da secagem, analisou-se o encolhimento do papel durante a secagem, relacionando-o com as condições operacionais do processo, as características físicas e a qualidade do produto. O secador desenvolvido neste trabalho mostrou-se adequado para a secagem do papel recic1ado tipo cartão, apresentando uma eficiência energética compatível com a dos secadores utilizados na indútria papeleira (24,53%). Verificou-se que o aumento da temperatura e da velocidade do ar de secagem influencia positivamente no processo, reduzindo significativamente o tempo de secagem. No entanto, a qualidade do papel é inferior nas condições mais dráticas de secagem, obtendo-se um produto final com superfície menos uniforme e mais ressecada. No estudo de encolhimento durante a secagem, assim como na análise da qualidade da superfície (J
Abstract: Even though the great technological advances, the paper still carries out an important role in the culture and in the diffusion of information. Although it is produced by a renewable source, as the wood, technology allowing paper reuse is available. A selective pick up is necessary for the pulp processing from recovered fibers. The paper recycling allows a great reduction of the amount of urban solid residues, avoiding the use of natural sources as wood and water, besides decreasing a lot the energy consumption in the paper industry. The production of the cellulose pulp is the first great energy consumer in the process of paper production, followed by the paper drying process. The drying is a complex process, of great importance, not only in energy terms, but for the quality of the final product. In this context, this work had the objective to analyze the drying of cellulose pulp made from recovered fibers for the production of card type recycled paper. For this, a convective dryer was projected, in laboratorial scale, for the drying of the paper pulp. The drying curves as a function of different operating conditions were analyzed and the paper dessorption isotherms were determined by the dynamic method. An analysis of the product quality was accomplished for different conditions, as well as the process energy consumption evaluation. A comparative study between the natural drying (used in small productions) and the drying by forced convection was also effectuated. To complement the drying analysis, the shrinkage of the paper was evaluated during the drying and related to the operating conditions, physical characteristics and quality of the product. The dryer developed in this work showed to be appropriate for the drying of the recycled card type paper , presenting energy efficiency compatible with dryers used in paper industries (24,53%). It was verified that the increase of the temperature and velocity of the drying air influenced the process reducing the drying time. However, the quality of the paper is poor for severe operating conditions, leading to a less uniform final product, having a very dry surface. In the paper shrinkage study during drying, as well as in the analysis of the surface quality, similar results were gotten for the papers dried at 70 and 80°C. Significant modifications of structural properties and a low quality of the product were verified for the paper dried at 90°C, indicating a limit to the air temperature for the convective drying of the analyzed recycled papeI. The paper dried at 90°C suffered 15% of surface shrinkage and also 40% of linear and volume reduction during the falling rate drying phase. The paper dried under softer operating conditions (66°C; O,22m/s) presented characteristics similar to the paper naturally dried. Thus, a type card recycled paper can be producted with adequate quality using the convective drier, reducing significantly the necessary time for the drying af the paper sheet
Doutorado
Engenharia de Processos
Doutor em Engenharia Química

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Ouředníčková, Veronika. "Mikrobiální kontaminace fotografických materiálů." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2010. http://www.nusl.cz/ntk/nusl-216625.

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This diploma work is focused on a study of microbial contamination of photographic materials. In the first part of this work the information about the archive and museum microbial contaminations were collected. The most frequent contaminants of photographic collections – Penicillium chrysogenum and Aspergillus niger were studied. Their activity on photographic papers Fomaspeed and Fomabrom was evaluated. It was found that at the given experimental conditions the image layers of Fomaspeed paper are resistant to fungi mycelium growth. On the other hand, the Fomabrom paper image layer was irrecoverably damaged by action of fungi mentioned above. The degree image layer deterioration was evaluated with the aid of sensitometric curves.

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Habash, Ashraf. "Paper Digital Classes (PDC)." Thesis, Blekinge Tekniska Högskola, Avdelningen för för interaktion och systemdesign, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-5328.

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There are many attempts to bridge paper digital gap, new artifacts and tools are being delivered continuously. Many of these artifacts work with paper and cooperate with other artifacts. Despite the fact that these artifacts are good enough to perform their work, they tend to be dull in exchanging data and cooperating with other artifacts. This causes a problem especially when artifact cooperation is essential. In order to solve this we need to have a standard to present the data used in the artifacts and facilitate communication among artifacts. Paper Digital Classes is a new standard that aims at providing a standard implementation of the artifacts in matters of data exchange and interoperability.
Med dagens teknik är det möjligt att skicka till exempel e-post direkt från ett papper utan att röra vid datorn. Genom att använda en särskild digital penna överförs texten man skriver på papper direkt till datorn. Jag har undersökt olika system och verktyg som berör läsning och överföring från papper till digitala dokument. Jag har utifrån min studie tagit fram en standard, PDC, Paper Digital Classes, som låter olika verktyg interagera som om de vore ett. PDC kan komma att få stor betydelse för framtida dokumenthantering. Tekniken underlättar att skicka e-post från ett pappersdokument, redigera pappersdokument och överhuvudtaget all interaktion mellan fysiska och digitala dokument. PDC kan också komma till god hjälp när det gäller att utveckla nya, användbara produkter.
Ashraf Habash Gamla Infartsv. 3A, lhg 510 371 41 Karlskrona (mob) +46 734 08 79 67 (work) +46 457 386 300

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49

Habash, Ashraf. "Paper Digital Classes (PDC)." Thesis, Blekinge Tekniska Högskola, Avdelningen för för interaktion och systemdesign, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-5329.

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There are many attempts to bridge paper digital gap, new artifacts and tools are being delivered continuously. Many of these artifacts work with paper and cooperate with other artifacts. Despite the fact that these artifacts are good enough to perform their work, they tend to be dull in exchanging data and cooperating with other artifacts. This causes a problem especially when artifact cooperation is essential. In order to solve this we need to have a standard to present the data used in the artifacts and facilitate communication among artifacts. Paper Digital Classes is a new standard that aims at providing a standard implementation of the artifacts in matters of data exchange and interoperability. PDC has a direct industrial impact, this was noticed by Sparbanksstiftelsen Kronan and they have awarded me a scholarship for the project.
Med dagens teknik är det möjligt att skicka till exempel e-post direkt från ett papper utan att röra vid datorn. Genom att använda en särskild digital penna överförs texten man skriver på papper direkt till datorn. Jag har undersökt olika system och verktyg som berör läsning och överföring från papper till digitala dokument. Jag har utifrån min studie tagit fram en standard, PDC, Paper Digital Classes, som låter olika verktyg interagera som om de vore ett. PDC kan komma att få stor betydelse för framtida dokumenthantering. Tekniken underlättar att skicka e-post från ett pappersdokument, redigera pappersdokument och överhuvudtaget all interaktion mellan fysiska och digitala dokument. PDC kan också komma till god hjälp när det gäller att utveckla nya, användbara produkter.
Ashraf Habash Gamla Infartsv. 3A 371 41 Karlskrona (mob) +46 734 08 79 67 (work) +46 457 386 307 Ashrafhabash@msn.com www.uth.se

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Polat, Osman. "Through drying of paper." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=75904.

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The first comprehensive set of measurements is obtained for rates of through drying paper with all drying conditions measured and controlled. Complete pressure drop-drying rate curves are determined for 235 handsheets of kraft paper of basis weights 25-150g/m$ sp{ rm 2}$ dried in air over a wide range of temperatures and throughflow rates.
The previous procedure of calculating permeability by Darcy's law is substantially in error at relevant throughflow rates. A new characteristic dimension for flow through both dry and moist paper is determined by application of fundamental momentum transport principles. During through drying the value of the d$ sb{ rm p}$ drops substantially from an upper to a lower asymptotic limit, shown to correspond to known water-fibre relations. A theoretically based Re-f-d$ sb{ rm p}$ treatment is shown to be a more powerful method than those used previously.
A comprehensive, tested correlation for through drying rates in the constant rate period is reported. Through drying is demonstrated to start with an increasing rate period during which, for industrial conditions, about half the water is removed. An original treatment, "drying period diagrams", shows the extent of the increasing, constant and falling rate periods as a function of drying conditions. The concept of an increasing-constant-falling rate triple point, X$ sb{ rm ICF}$, shows that typically there will be no constant rate period for industrial conditions of through drying light weight paper of low moisture content.
Sherwood number is calculated for the constant rate period of drying using the characteristic dimension and interfacial transfer area for moist paper determined by momentum transfer analysis. Sherwood number is related to drying conditions and to transport phenomena within the sheet.
Through drying rates are successfully predicted by a model which treats the process as three drying periods, i.e. increasing, constant and falling rate, with a variable specific surface of paper.

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