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Bioacumulações de Cd, Ni, Pb e Zn durante os crescimentos de Salvinia minima e Lemna valdiviana
(Universidade Federal de São Carlos, 2014-07-31) Iha, Danilo Sinhei; Bianchini Júnior, Irineu; https://lattes.cnpq.br/0659731944736389; https://lattes.cnpq.br/2332539900317166
Metals are dispersed easily in environments and are bioconcentrated in tissues of many organisms causing risks to the health and stability of aquatic ecosystems even at low concentrations. The use of plants in phytoremediation has been evaluated in order to mitigate environmental contamination since it has large capacity to adsorb and/or accumulate metals. This study evaluated the growth and phytoremediation of Salvinia minima and Lemna valdiviana grown in different concentrations of Cd, Pb, Ni and Zn. The growths were determined through measurements of leaf area by photographic images. The cultures were performed in a continuous flow (residence time = 2 days), under controlled temperature (23 ºC) and photoperiod (12/12h; radiation intensity: 4.31x10- 3 μmol sec-1 cm-2). The selected concentrations were 0.003 0.030 0.300 and 0.600 mg L-1 Cd; 0.020 0.200 and 0.400 mg L-1 Ni; 0.01 0.10 and 1.00 mg L-1 Pb and 0.10 1.00 10.0 100.0 and 1,000.0 mg L-1 Zn. The metals selection derived from the difficulty of its removal by conventional methods, and the selection of concentrations was based on values toxic to humans and on the maximum values allowed by Brazilian legislation for effluent discharge. None S. minima growth in concentrations of 0.300 mg L-1 Cd and 10.0 mg L-1 Zn were observed. L. valdiviana showed no growth when cultured at concentrations of 0.600 mg L-1 Cd; 0.10 and 1.00 mg L-1 Pb; and greater than 100.0 mg L-1 Zn. Individuals of S. minima bioaccumulated maximum 0.803 mg g-1 Cd; 0.677 mg g-1 Ni; 1.786 mg g-1 Pb and 10.464 mg g-1 Zn. L. valdiviana bioaccumulated maximum 1.15 mg g-1 de Cd; 0.045 mg g-1 de Ni e 62.465 mg g-1 de Zn. The metals content in plant tissues increased and the growth coefficients decreased when progressively increased the Cd, Pb and Ni concentrations. We conclude that, depending on the concentration, the two species of macrophytes can be used to phytoremediate effluents with metals and S. minima is more efficient on Ni, Pb and Zn removal and L. valdiviana on Cd removal. The Cd and Ni concentrations allowed by Brazilian law were toxic for both species and the allowed Pb concentration were toxic for Lemna valdiviana.
Previsão da contração e da variação dimensional em componentes injetados através de simulação computacional
(Universidade Federal de São Carlos, 2014-07-31) Kiam, Thyago Morette; Lucas, Alessandra de Almeida; https://lattes.cnpq.br/9754332336954137; Pessan, Luiz Antonio; https://lattes.cnpq.br/8276650236213537; https://lattes.cnpq.br/4720953107199335
Both, average linear shrinkage and dimensional variation behavior for injection-molded components influence its final application performance, hence the project overall quality and profit [1]. The use of simulation software for estimating dimensional variation is still incipient due to some factors such as lack of proficient users, code simplifications and lack of raw material proper characterization. On the Brazilian context, this third item is particularly critical, once the coefficients for warpage results improvement for the main commercial code available on the market, Autodesk Moldflow Insight (AMI); requires a very specific characterization named ‘corrected residual in-mold stress’ (CRIMS), just generated by the software developers in a quite complex and low cost-benefit process for national resin suppliers. The present work used computational experimentation based on commercial code AMI 2013 aiming both: to generate CRIMS coefficients from correlation studies involving optimization algorithm, based on Cellere and Luchetta work [2]; and to perform a case study proposing a method that make use of optimization algorithm and Monte Carlo Simulation in order to drive both, design and process decisions; in the end providing a estimative of the dimensional variation behavior on early design and mold development phases. The results level of error obtained with the CRIMS coefficients generated on this work is close to the results generated from coefficients generated by the supplier for the same material (confidential data) that represents the state-of-the-art of correction coefficients generation; confirming the potential for the method showed in this work. The adaptable nature of the method described on Cellere and Lucchetta paper [2] was maintained.
Incorporação da sustentabilidade em cadeias de suprimentos: práticas estabelecidas e barreiras encontradas
(Universidade Federal de São Carlos, 2014-07-31) Nascimento, Annelise Mendes; Alcântara, Rosane Lúcia Chicarelli; https://lattes.cnpq.br/9931944429943729
This research aims to present and analyze the practices that can be established by focus companies with their suppliers, distributors and consumers, so that sustainability is embedded in their supply chains. Moreover, as a way to better understand the dynamics of sustainability, the research also analyzes the barriers faced by organizations when adopting this type of practice. From the information obtained by the technique of systematic literature review, we developed a questionnaire for the empirical stage of this research - a survey with organizations known for adopting sustainable practices. Among the results, it is emphasized that the practices aimed at environmental issues are further explored, both in literature and empirically. Regarding the practices with suppliers, those that require a lesser degree of involvement between companies - less collaboration - and had a more assessment nature stood out. Considering the chain downstream, practices among distributors are still poorly known, both in literature and empirically; and practices that stood out with consumers referred to the sharing of information, and labeling of products. Considering the barriers, the more relevant indicated by respondents was the cost. From the results obtained, proposals were outlined, both theoretical and practical, about the incorporation of sustainable practices throughout the supply chain, and how to overcome potential barriers. It is believed that these proposals can be a starting point for further academic research, and still be used by managers interested in the sustainable management of their organizations.