This study aimed to analyze the characteristics of the scientific research that approaches Reverse Logistics (RL) from the perspective of Performance Evaluation (PE). For this purpose, ProKnow-C was used to select 21 articles to compose a Bibliographical Portfolio (BP). Among the results, we mention Govindan, Sarkis, Zhu and Lai as prominent authors. By analyzing the articles, it was perceived that most of them perform the RL and PE fields separately and present tools that consider the alignment of the indicators with the strategy. Also, the articles lack of a structured PE process that could serve as a subsidy to the practice of logistics management. The results present that there is a theoretical gap in the literature of a PE model of RL.
ElEY tA8() RAT ORY LIBRARY AND DOCUMENTS SECTIONPresented at the American Chemical Society 1981 Spring Symposium, Atlanta, GA, March 25-27, 1981; and DISCLAIMER .This document was prepared as an account of work sponsored by the United States Government. While this document is believed to contain correct information, neither the United States Government nor any agency thereof, nor the Regents of the University of California, nor any of their employees, makes any warranty, express or implied, or assumes any legal responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by its trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof, or the Regents of the University of California. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof or the Regents of the University of California. The chain reaction between sulfur (IV) and oxygen has been studied in the pH region of 3.0 and 4.7 where bisulfite ion, BS03-, is the principal species. Preliminary measurements were made with a two-phase gas-aqueous, system. To avoid mass-transfer problems. the remaining studies were done on a single aqueous phase with no gas phase present and using an oxygen meter to follow the concentration of dissolved oxygen as a function of time. Empirical rate laws were determined for a variety of conditions, in-' eluding the presence of ethanol, manganous ion and ultra violet light. Without additives the chain appears to be terminated by a bimolecular reaction of chain carriers, since the rate law contains powers of multiples'of,I/2. Ethanol inhibits the reaction by chain'termiDation involving a single chain .carrier. Manganous ion, is a strong catalyst. apparently through the introduction of a new propagating path as well as participation in the initiation. Ultra violet light presumably initiates the chain. the "simplest" resolution of the rate laws into the three components: initiation, propagation and termination is suggested. The data do not establish the identity of the intermediates; other info,rmation will be necessary to fix mechanisms of the reaction.The oxidation of bisulfite ion by oxygen:is of importance in the lime/limestone processes for removing sulfur dioxide from stack gases of coal-burning power plants as well as in the conversion of ~tmospheric SOl to sulfuric acid, the prinCipal component of acid rain. In the various Flue Gas Desul-2 'furization processes, there are advantages to be gained in accelerating this oxidation in some cases and in slowing it down in others. Thus a basic understanding of the kinetics of the reaction is a desirable goal. Since Backstrom (1,2) reported studies of the therma...
Summary. The effect of common oilfield biocides, corrosion inhibitors, scale preventives, and alcohols on the rate of O2 scavenging by sulfite/bisulfite is described. Emphasis is placed on the effect of the functional group of each of the chemical types. An attempt is made to explain the results in terms of the free-radical mechanism. Introduction In many EOR floods, it is difficult to control corrosion and polymer degradation without sufficient removal of O2 from the polymer degradation without sufficient removal of O2 from the water system. The most common treatment for this removal uses the oxidation-reduction reaction of sulfite/bisulfite with O2. In many of these applications, successful treatment includes not only reducing the O2 to acceptable levels but reaching these levels within a limited time. Therefore, it is important to understand any conditions that can affect the rate of the scavenging reaction. Since Backstrom's and Alyea and Backstrom's studies of the thermal and photo-oxidation of sodium sulfite solutions, this scavenging reaction has been known to proceed by a chain mechanism. The literature suggests that this reaction is quite sensitive to the presence of additional chemicals. This sensitivity is not surprising because, as a chain reaction, the process involves highly reactive chain carriers. Because of this extreme sensitivity, the exact reproducibility necessary for a complete mechanistic analysis is a difficult task. In many cases, however, the reproducibility of +/- 20% that we experienced is adequate to indicate the mechanism by which the additive affects the reaction. This paper reports preliminary investigations into the effects of common oilfield chemicals on the O2-scavenging reaction, with insights into mechanistic explanations when possible. These water-soluble oilfield chemicals include biocides, corrosion inhibitors, scale preventives, and alcohols, which are used as solvents and freeze-point depressants. Many of the actual commercial chemicals are complex multicomponent formulations or contain active species that are complex multifunctional chemical structures. Because isolation of the effect of one component or functional group in these complex formulations is difficult, simple model compounds have been used in this study. These model compounds have been chosen with consideration to purity, simplicity, and the presence of the appropriate chemical functional group. Experimental The reaction cell consisted of a water-jacketed 250-mL beaker and a rubber stopper. Fitted into the stopper wasa combination pH electrode attached to an Orion 407A(TM) specific ion meter, pH electrode attached to an Orion 407A(TM) specific ion meter,a YSI 5750(TM) O2 probe attached to an O2 meter, andtwo gauge-18 syringe needles for solution injection and volume relief. Both pH readings and O2 levels were simultaneously recorded on a dual-channel recorder. Temperature was regulated at 25 degrees C [77 degrees F] with a circulating water bath through the outside jacket of the cell. All measurements were performed with 1% KCl as the test solution. The pH of the performed with 1% KCl as the test solution. The pH of the reacting solution was regulated to +/ 0.1 unit by the manual addition of a dilute NaHCO3 solution. Method of Analysis The rate of a chain reaction of long chain length may be represented symbolically by a chain-initiating step, I, a chain-propagating step, P, and a chain-terminating step, T: (1) where R is the rate of a chain reaction and n is a small integer, usually 1 or 2. The rates of initiation and termination are equal-i.e., I= T. The factor I/T is introduced to cancel from the rate law the concentrations of chain carrier(s) that appear in P and T. If the termination involves one chain carrier, n will be unity; if it involves two chain carriers, n will be two. Analysis of rate expressions in terms of Eq. 1 can help in the determination of the role of additives in the chain process. This method of analysis may not lead to a unique, unambiguous resolution into initiation, propagation, and termination expressions in all cases. The following guidelines, however, have been used in an attempt to produce a consistent and physically realistic interpretation.1. The additive is allowed to affect only one process.2. The concentration of the additive to the first power is present in the rate-law expression for the affected process. This is consistent with a bimolecular collision process. SPEPE P. 137
RESUMO -Junto ao crescimento da produção de biodiesel, possíveis acidentes de derramamento se tornam mais susceptíveis a ocorrerem, podendo gerar maiores danos ao ambiente. Em vista de atenuar tais acidentes ambientais pode-se utilizar o processo de biorremediação como uma alternativa viável. Este método é baseado na atividade biológica de microorganismos, e por isso é preciso garantir condições ambientais favoráveis à sobrevivência, crescimento e atividade destes, a fim de se obter maiores índices de remoção de contaminantes. Tendo em vista estes fatores, o objetivo do presente trabalho foi utilizar dois biorreatores em condições controladas, sendo um biorreator de bandeja e outro rotativo, buscando assim as melhores condições para o processo de biodegradação de biodiesel de processo (biodiesel+glicerina) em solo a fim de se obter remoção deste contaminante. Os biorreatores apresentavam concentrações iniciais de biodiesel de 22.000, 78.000 e 50.000 mg BB.kg -1 de solo, e as remoções obtidas de BB foram de 100, 90, 6 e 33,9% os biorreatores do tipo bandeja, e 80, 65 e 43% os biorreatores do tipo rotativo. Com estes resultados verificaram-se valores de remoção de BB consideráveis principalmente em se tratando dos biorreatores do tipo bandeja.Palavras chave: biorremediação, biodiesel bruto, biorreatores INTRODUÇÃOAlternativas para os problemas de caráter ambiental são motivações para inúmeras pesquisas e exigências legislativas no mundo moderno. No tocante dos combustíveis fósseis e do esgotamento das reservas petrolíferas, o interesse pelo uso de biocombustíveis tem aumentado.O biodiesel vem sendo aderido a matriz energética brasileira (Knothe et al., 2006), pois apesar de suas propriedades físico-químicas serem semelhantes ao do diesel proveniente do petróleo, ele libera menos gases poluentes.No Brasil, a Lei Federal Nº 11.097 (13/01/2005), determina que o diesel comercial deva ser uma mistura com 2% de biodiesel chegando na atualidade a 5% e este valor deve atingir ainda índices maiores.Tendo em vista estes fatores, a produção e consumo de biodiesel tem crescido, e com isso estudos sobre sua biodegrabilidade se
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