900 resultados para Garbage and Recycling Behavior


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We here report the first magnetically recoverable Rh(0) nanoparticle-supported catalyst with extraordinary recovery and recycling properties. Magnetic separation has been suggested as a very promising technique to improve recovery of metal-based catalysts in liquid-phase batch reactions. The separation method is significantly simple, as it does not require filtration, decantation, centrifugation, or any other separation technique thereby, overcoming traditional time- and solvent-consuming procedures. Our new magnetically separable catalytic system, comprised of Rh nanoparticles immobilized on silica-coated magnetite nanoparticles, is highly active and could be reused for up to 20 times for hydrogenation of cyclohexene (180,000 mol/mol(Rh)) and benzene (11,550 mol/mol(Rh) under mild conditions. (c) 2007 Elsevier B. V. All fights reserved.

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Photochemical and photophysical properties of fac-[Re(CO)(3)(Clphen)(trans-L)](+) complexes, Clphen = 5-chloro-1,10-phenathroline and L = 1,2-bis(4-pyridyl)ethylene, bpe, or 4-styrylpyridine, stpy, were investigated to complement the understanding of intramolecular energy transfer process in tricarbonyl rhenium(I) complexes having an electron withdrawing group attached to polypyridyl ligands. These new compounds were synthesized, characterized and the photoisomerization quantum yields were accurately determined by (1)H NMR spectroscopy. The true quantum yields for fac-[Re(CO)(3)(Clphen) (trans-bpe)](+) were constant (Phi = 0.55) at all investigated irradiation wavelengths. However, for fac-[Re(CO)(3)(Clphen)(trans-stpy)](+), similar true quantum yields were observed only at higher energy irradiation (Phi(313 nm) = 0.53 and Phi(365 nm) = 0.57), but it decreased significantly at 404 nm (Phi = 0.41). These results indicated different deactivation pathways for the trans-stpy complex photoisomerization. Quantum yields decreased as the (3)IL(trans-L) and (3)MLCT(Re -> NN) excited states become closer and the behavior was discussed in terms of the excited state energy gaps. Additionally, luminescence properties of photoproducts, fac-[Re(CO)(3)(Clphen)(cis-L)](+), were also investigated in different environments to analyze the relative energy of the (3)MLCT(Re -> Clphen) excited state for each compound. (C) 2011 Elsevier B.V. All rights reserved.

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The present paper describes the physical-chemical characterization and electrochemical behavior of a new nanomaterial formed by the addition of cadmium and cobalt atoms into the structure of nickel hydroxide nanoparticles, these ones synthesized by an easy sonochemical method. Particles of about 5 nm diameter were obtained and characterized by high resolution transmission electron microscopy (HRTEM), X-ray diffraction and Raman spectroscopy. Different nickel hydroxide nanoparticles were immobilized onto transparent conducting substrates by using electrostatic layer-by-layer providing thin films at the nanoscale and the electrochemical behavior was investigated. The formation of a mixed hydroxide was corroborated by observation of very interesting properties as redox potential shifting to less positive potentials and high stability when submitted to long electrochemical cycling or high times of ultrasonic synthesis, suggesting practical applications. (C) 2008 Elsevier B.V. All rights reserved.

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The fac-[Re(CO)(3)(Me(4)phen)(trans-L)](+) complexes, Me(4)phen = 3,4,7,8-tetramethyl-1,10-phenanthroline and L = 4-styrylpyridine, stpy, or 1,2-bis(4-pyridyl)ethylene, bpe, were synthesized and characterized by their spectroscopic, photochemical, and photophysical properties. The complexes exhibit trans-to-cis isomerization upon 313, 334, 365, and 404 nm irradiation, and the true quantum yields can be efficiently determined by absorption changes combined with (1)H NMR data. For fac-[Re(CO)(3)(Me(4)phen)(trans-bpe)](+) similar quantum yields were determined at all wavelengths investigated. However, a lower value (phi(true) = 0.35) was determined for fac-[Re(CO)(3)(Me(4)phen)(trans-stpy)](+) at 404 nm irradiation, which indicates different pathways for the photoisomerization process. The photoproducts, fac-[Re(CO)(3)(Me(4)phen)(cis-L)](+), exhibit luminescence at room temperature with two maxima ascribed to the (3)IL(Me4phen) and (3)MLCT(Re -> Me4phen) excited states. The luminescence properties were investigated in different media, and the behavior in glassy EPA at 77 K showed that the contribution of each emissive state is dependent on the excitation wavelength. The photochemical and photophysical behavior of the complexes were rationalized in terms of the energy gap of excited states and can be exploited in photoswitchable luminescent rigidity sensors.

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In recent times, increasing attention has been paid to the use of renewable resources particularly of plant origin keeping in view the ecological concerns, renewability and many governments passing laws for the use of such materials. On the other hand, despite abundant availability of lignocellulosic materials in Brazil, very few attempts have been made about their utilization, probably due to lack of sufficient structure/property data. Systematic studies to know their properties and morphology may bridge this gap while leading to value addition to these natural materials. Chemical composition, X-ray powder diffraction, and morphological studies and thermal behavior aspects in respect of banana, sugarcane bagasse sponge gourd fibers of Brazilian origin are presented. Chemical compositions of the three fibers are found to be different than those reported earlier. X-ray diffraction patterns of these three fibers exhibit mainly cellulose type I structure with the crystallinity indices of 39%, 48% and 50% respectively for these fibers. Morphological studies of the fibers revealed different sizes and arrangement of cells. Thermal stability of all the fibers is found to be around 200 degrees C. Decomposition of both cellulose and hemicelluloses in the fibers takes place at 300 degrees C and above, while the degradation of fibers takes place above 400 degrees C. These data may help finding new uses for these fibers. (C) 2009 Elsevier B.V. All rights reserved.

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The paper analyses Gender Equality, Gender Equity and policies of combating inequality at workplace to make the society equal as a case study of Sweden. The aim of paper is see the gender equality, gender equity, discrimination against women at workplace and to describe the policies combating inequality in the welfare state of Sweden. This work highlights the gender equality in terms of institutionalizing gender equality, gender equity, gender and pay gap, parental leave, gender and the pension system and sexual behavior directed towards women and policies combating inequality to bring equality in society. For my research I used the secondary data the fact sheets, scientific literature, statistics from eurostate of Sweden and case studies about Swedish society and the theoretical explanation to explain the phenomena. To achieve my aim I used the combination of both qualitative and quantitative methods of research. I showed the empirical evidences of these phenomena from the Swedish society and theoretical analysis about equality and equity of gender in different wakes of life. I found an interesting conclusion that there are good policies and legislation to combat inequality to bring society but there are no policies to change the perception of society about male and female role.

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Predator-prey relationships are an important aspect of the natural world, and, because of its relevance to survival and natural selection, is an interesting relationship to study. In amphibian larvae, level of activity and landscape use are often what determines the survival as prey. I studied the anti-predator behavior of the North American bullfrog (Rana catesbeiana) tadpoles when presented with dragonfly (Aeshna) larvae, a known predator of tadpoles. Tadpoles were acclimated to four different habitats with varying degrees of habitat cover, and were transferred to a new habitat with a degree of cover equal to one of the acclimation tanks. A restrained predator, and thus its chemical cue, was introduced, and the behavior, particularly the use of the habitat cover to hide from the perceived risk of predation was observed. A significantly higher frequency of inactivity was found in tank I than in II and III, and inactivity followed a general trend of decreasing with increasing habitat cover. Difference in tank cover was not found to have a significant effect on swimming behavior, but did have a significant effect on hiding behavior, which increased with higher availability. Foraging decreased significantly with the addition of a predator, but did not vary significantly with different levels of cover. Hiding behavior and reducing conspicuous behaviors (like foraging) are probably the behaviors that afford the tadpole the most success at eluding a predator in their natural environment.

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Esse artigo estabelece uma base para pesquisas que tratam da relação entre pobreza, distribuição de recursos e operação do mercado de capitais no Brasil. O principal objetivo é auxiliar a implementação de políticas de reforço de capital dos pobres. A disponibilidade de novas fontes de dados abriu condições inéditas para implementar uma análise de posse de ativos e pobreza nas áreas metropolitanas brasileiras. A avaliação de distribuição de recursos foi estruturada sobre três itens: Capital físico, capital humano e capital social. A estratégia empírica seguida é de analisar três diferentes tipos de impactos que o aumento dos ativos dos pobres podem exercer no nível de bem estar social. A primeira parte do artigo avalia a posse de diferentes tipos de capitais através da distribuição de renda. Esse exercício pode ser encarado como uma ampliação de medidas de pobreza baseadas em renda pela incorporação de efeitos diretos exercidos pela posse de ativos no bem estar social. A segunda parte do artigo descreve o impacto de geração de renda que a posse de ativos pode ter sobre os pobres. Estudamos como a acumulação de diferentes tipos de capital impactam os índices de pobreza baseados na renda usando regressões logísticas. A terceira parte estuda o efeito que o aumento da posse de ativos dos pobres tem no melhoramento da habilidade dos indivíduos pobres em lidar com choques adversos da renda. Estudamos a interação entre a dinâmica da renda, imperfeições do mercado de capitais e comportamentos financeiros levando em consideração diferentes horizontes de tempo. As questões de longo prazo estão relacionadas com o estudo das flutuações de renda de baixa freqüência e ciclo da vida da posse de ativos usando análise de coorte. As questões de curto prazo estão relacionadas com o comportamento do pobre e as perdas de bem estar ao lidar com hiatos de alta freqüência entre renda e consumo desejado. A análise da dinâmica de renda e pobreza é conduzida a partir da combinação de dados de painel de renda com dados qualitativos sobre comportamento financeiro de curto prazo das famílias.

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Over one-third of global food production goes to waste while over 850million people are fighting chronic hunger. The United States is the world’s largest food waster. One third of America’s food with an economic value of US$161 billion is wasted and less than 7% is recycled. American food waste ends up in landfills creating powerful methane gas emissions. South Korea, on the other hand, has implemented the world’s strictest food waste laws, and today diverts 93% of wasted food away from landfills turning such waste into powerful economic opportunities. This Master Thesis investigates the reasons behind global food waste by comparing South Korea and the US. It explores what these two nations are doing to address their respective food waste problems, South Korea successfully, the US not. The paper looks at the two countries’ respective policies and national characteristics, which impact decision-making and recycling processes. The effort concludes that South Korea has embarked on a necessary paradigm shift turning food waste into powerful economic drivers leading to a sharp decline in food waste. In the US, food waste continues to be a major problem without a national strategy to remedy waste. Any effort in the US, while laudable, is sporadic and local, and hence the US misses out on possibly important economic growth opportunities.

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Customer participation has been studied for decades; however, it gained a postmodern perspective around the year 2000. Customers have become co-creators of personalized experiences, moving from the audience to the stage. In the educational context, students must take responsibility for their learning process and participate in the production of the service. This changing is providing opportunities and challenges for higher education institutions (HEIs) to redefine their relationship with stakeholders, especially with students. This study is based on the service dominant logic (SDL) perspective because students are assumed to take the role of co-creators of knowledge in the educational setting. The research uses adapted frameworks and concepts applied in organizational, knowledge-intensive business services (KIBS) and also medical studies to advance the understanding of value co-creation in the HEI context. The current study addresses a lack of research in the higher education context focusing on defining students’ participation and students’ empowerment in higher education context. An empirical investigation was developed with traditional schools in Brazil. This investigation allowed the description of the constructs in the specific context. The description of student participation in HEIs context reflects the relevance of three dimensions – information sharing, personal interaction and responsible behavior. In the Brazilian context, responsible behavior is the weakest dimension in the construct, because the responsibilities are unbalanced between students and professors. The main reasons identified for this unbalanced relation were cultural issues and local regulation. Student empowerment was described as composed by four dimensions – meaningfulness, competence, impact and choice; however, one of them – choice – was identified as the weakest dimension, facing cultural and bureaucratic barriers for implementation in the Brazilian educational context. Moreover, interviewees spontaneously cited the idea of trust in the faculty as an important antecedent of student participation that must be considered when analyzing student participation and empowerment mechanisms. An additional contribution was the proposal of a theory-based framework for understanding the service dominant logic perspective in the HEI context, in which student participation and student empowerment were explored as mechanisms leading to positive student behavior toward institution.

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A aprovação e posterior regulamentação da Lei 12.305, de 2 de agosto de 2010, que institui a Política Nacional de Resíduos Sólidos – PNRS estabeleceu necessidades de uma nova articulação entre os três entes federados – União, Estados e Municípios – o setor produtivo e a sociedade em geral na busca de soluções para os problemas atuais na gestão de resíduos sólidos. Baseada principalmente no conceito de responsabilidade compartilhada, toda a sociedade – cidadãos, setor produtivo, governos e sociedade civil organizada – passa a ser responsável pela gestão dos resíduos sólidos por ela produzidos. Falando especificamente do cidadão, um dos atuais desafios é saber como seu comportamento em relação à separação de resíduos recicláveis no âmbito do seu domicílio se relaciona com os objetivos e metas de reciclagem do município. Considerou-se uma amostra (N=310) de residentes em domicílios do Rio de Janeiro, e os dados coletados foram analisados segundo o modelo ABC de STERN. Os resultados empíricos mostraram que as variáveis associadas ao hábito, às normas sociais diretas e às atitudes afetivas têm peso significativo na predição do modelo do comportamento pró-reciclagem. Como contribuição prática, espera-se que o PMGIRS do Rio de Janeiro possa ser aprimorado, contribuindo para o aumento da participação do cidadão na separação de resíduos recicláveis em seu domicílio, auxiliando os gestores municipais nas decisões necessárias ao cumprimento de objetivos e metas relacionados com a reciclagem na cidade do Rio de Janeiro.

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The effects of serum and brain calcium concentration on rat behavior were tested by maintaining animals on either distilled water (N = 60) or water containing 1% calcium gluconate (N = 60) for 3 days. Animals that were maintained on high calcium drinking water presented increased serum calcium levels (control = 10.12 ± 0.46 vs calcium treated = 11.62 ± 0.51 µg/dl). Increase of brain calcium levels was not statistically significant. In the behavioral experiments each rat was used for only one test. Rats that were maintained on high calcium drinking water showed increased open-field behavior of ambulation (20.68%) and rearing (64.57%). on the hole-board, calcium-supplemented animals showed increased head-dip (67%) and head-dipping (126%), suggesting increased ambulatory and exploratory behavior. The time of social interaction was normal in animals maintained on drinking water containing added calcium. Rats supplemented with calcium and submitted to elevated plus-maze tests showed a normal status of anxiety and elevated locomotor activity. We conclude that elevated levels of calcium enhance motor and exploratory behavior of rats without inducing other behavioral alterations. These data suggest the need for a more detailed analysis of several current proposals for the use of calcium therapy in humans, for example in altered blood pressure states, bone mineral metabolism disorders in the elderly, hypocalcemic states, and athletic activities.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The aim of this research study was to evaluate the reproductive performance of tinamous submitted to five different male:female ratios. The study was carried out with 72 birds in a randomized experimental design with 4 replications. Tinamous were housed in cages, using the ratios of one (1:1), two (2:1), three (3:1) and four (4:1) females per male, and also one male was housed with three females individually (3R:1), in a rotational system. Reproductive records of the breeding season from September 2004 to March 2005 were used. The reproductive traits studied were: number of eggs laid, fertility, and percentage of eggs damaged and cracked by pecking. Nonparametric analyses of these traits were performed using Kruskal-Wallis test. Two replications of treatments 1:1 and 4:1, and one of treatment 2:1 were video-taped for three days, 12 hours/day. The videotapes were sampled according to the scan method to fit an ethogram. Birds were also watched for one hour per day to study dominance and agonistic behavior. None of the reproductive traits was affected by mating sex ratio (p<0.05). Female dominance could be related to displacement behavior (r=1.00), and male sitting in immobility plus sitting in activity behaviors were related to lower number of damaged eggs (r=-0.90). Social dominance was indirectly determined by displacement behavior in the study situation. A large number of damaged eggs occurred in all treatments, thereby not allowing a clear conclusion on the best male:female ratio.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)