Volume balance equation,availability analysis and the fundamental relation in the thermodynamics for the heat transfer man

An alternative form of the Second Law of Thermodynamics for systems experiencing volume-change work transfer interactions has been presented in a companion paper, from which the volume generation concept emerges in a similar way with what happens with entropy generation in the well established thermodynamics. The volume balance equation and the new concept of volume generation are introduced into the framework of thermodynamics in the present work. A volume balance equation is developed to apply to closed or open systems. Thermomechanical availability is evaluated taking into account these new developments and emphasis is given to the physical meaning of volume generation, which is closely related with the lost available work associated with irreversibilities of volume-change work transfer interactions. Special attention is given to the fundamental relation of thermodynamics, the volume generation concept being of crucial importance to set the conditions under which this relation applies to reversible or/and to irreversible processes.     

An improved general kinetic analysis of non-linear irreversible polymerisations

A method to predict average molecular weights before and after gelation for general irreversible non-linear polymerisations forming tree-like molecules is described. Recently developed numerical methods for solving two point boundary value problems are essential for the success of these calculations after gelation and open the way to eventually be able to efficiently predicting chain length distributions. Anionic and free-radical polymerisation of vinyl monomers in the presence of divinyl monomers or with transfer to polymer are taken as case studies. Comparison to experimental data and with simulation results obtained through “numerical fractionation” confirms the usefulness of current approach.     

Detection of biological and chemical agents using differential mobility spectrometry (DMS) technology

With international concern growing over the potential for chemical and biological terrorism, there is an urgent need for a sensor that can quickly and accurately detect chemical and biological agents. Such a sensor needs to be portable, robust, and sensitive, with fast sample analysis time. We will demonstrate the use of a micromachined differential mobility spectrometer (DMS) with these characteristics that can detect multiple agents simultaneously on a time scale of seconds. In this study, we have demonstrated the ability of the DMS to detect Bacillus subtilis spores, a surrogate for Bacillus anthracis spores, the causative agent of anthrax. Pyrolysis was used as the sample introduction method to volatilize the spores before introducing material into the DMS. Additionally, we examined the effect of pyrolysis on B. subtilis spores suspended in sterile water using SDS-PAGE. These experiments showed that the spores must be heated at 650/spl deg/C or greater for 5 s or at 550/spl deg/C for at least 10 s to be fragmented into particles considerably smaller than 10 kDa, which the DMS can detect. Several major biomarkers can be easily distinguished above the background of the sterile water in which the spores are suspended, and we hypothesize that additional biomarkers could be liberated by further optimizing conditions. The DMS also has shown promise as a detector for chemical weapon agents, and we have demonstrated the ability of the DMS to detect nerve and blister agent simulants at clinically relevant levels.     

Updates on biogas enrichment and purification methods: A review

The market for biogas production has been increasing every year all over the world. The use of biogas as an energy vector is accomplished through the most diverse applications, such as direct burning (thermal energy), internal combustion engines, and fuel cells. Besides direct applications, biogas can be used as a raw material for producing high added-value products, such as molecular hydrogen and renewable hydrocarbons, through a new enterprise concept, the biorefineries. Purity and quality control are determinant factors that enable the decision-making regarding the end use of biogas. Physical, chemical, and biological methods can be used in biogas upgrading processes as well as a combination of different techniques. This review aims to deepen the knowledge about relevant technologies for biogas purification. It also addresses the most efficient and feasible methods, challenges to be overcome, and main demands for future studies. Therefore, the presentation, in a detailed way, of the synergistic effects caused by components contained in natural biogas and the combinatorial methods for removing these contaminants, differentiates this from other works that approach only the purification techniques but do not point out their problems and causes more comprehensively. Thus, studies related to the combined effects of contaminants would be interesting in future works.     

Effect of alpha prime due to 475 °C aging on fracture behavior and corrosion resistance of DIN 1.4575 and MA 956 high performance ferritic stainless steels

The 475 °C embrittlement in stainless steels is a well-known phenomenon associated to alpha prime (α′) formed by precipitation or spinodal decomposition. Many doubts still remain on the mechanism of α′ formation and its consequence on deformation and fracture mechanisms and corrosion resistance. In this investigation, the fracture behavior and corrosion resistance of two high performance ferritic stainless steels were investigated: a superferritic DIN 1.4575 and MA 956 superalloy were evaluated. Samples of both stainless steels (SS) were aged at 475 °C for periods varying from 1 to 1,080 h. Their fracture surfaces were observed using scanning electron microscopy (SEM) and the cleavage planes were determined by electron backscattering diffraction (EBSD). Some samples were tested for corrosion resistance using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. Brittle and ductile fractures were observed in both ferritic stainless steels after aging at 475 °C. For aging periods longer than 500 h, the ductile fracture regions completely disappeared. The cleavage plane in the DIN 1.4575 samples aged at 475 °C for 1,080 h was mainly {110}, however the {102}, {314}, and {131} families of planes were also detected. The pitting corrosion resistance decreased with aging at 475 °C. The effect of alpha prime on the corrosion resistance was more significant in the DIN 1.4575 SS comparatively to the Incoloy MA 956.     

A methodology for unveiling global innovation networks: patent citations as clues to cross border knowledge flows

This paper presents a new methodology to describe global innovations networks. Using 167,315 USPTO patents granted in 2009 and the papers they cited, this methodology shows “scientific footprints of technology” that cross national boundaries, and how multinational enterprises interact globally with universities and other firms. The data and the map of these flows provide insights to support a tentative taxonomy of global innovation networks.     

An economic–probabilistic model for project selection and prioritization

This paper presents an economic–probabilistic model for project selection and prioritization that enables necessary investments and potential benefits and their inherent variability to be quantified, thus providing a stochastic analysis of expected returns for projects. The model was developed in three steps: definition of criteria; definition of the most appropriate method to be used; and model building. A practical test to evaluate the applicability and usefulness of the model comprising a portfolio of investment projects at a power distribution company was conducted. The results show three major contributions of the proposed model: i) a set of sufficiently complete criteria, ii) the combined use of economic and probabilistic approaches which qualifies the information available to decision makers, and iii) the use of financial language, which is more easily understood and has a concrete meaning for both management and technical staff.     

Avoided losses on LV networks as a result of microgeneration

In the scope of the discussions about microgeneration (and microgrids), the avoided electrical losses are often pointed out as an important value to be credited to those entities. Therefore, methods to assess the impact of microgeneration on losses must be developed in order to support the definition of a suitable regulatory framework for the economic integration of microgeneration on distribution networks.     

Short-term stability of NEO–PI–R personality trait scores in opioid-dependent outpatients.

The present study examined the short-term stability of personality trait scores from the Revised NEO Personality Inventory (NEO–PI-R) among 230 opioid-dependent outpatients. The NEO–PI-R is a 240-item empirically developed measure of the five-factor model of personality (Neuroticism, Extraversion, Openness, Agreeableness, and Conscientiousness). Participants completed the NEO–Pl-R at admission and again approximately 19 weeks later. Results indicated fair to good stability for all NEO–PI-R factor domain scores, with coefficients ranging from .68 to .74. Stability of NEO–PI-R scores was decreased among potentially invalid response patterns but was not significantly affected by drug-positive versus drug-negative status at follow-up. (PsycINFO Database Record (c) 2010 APA, all rights reserved)