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61.
The purpose of this study is to increase of the flammability properties of the glass fiber (GF)–reinforced poly (lactic acid)/polycarbonate (PLA/PC) composites. Ammonium polyphosphate (APP) and triphenyl phosphate (TPP) were used as flame retardants that are including the organic phosphor to increase flame retardancy of GF‐reinforced composites. APP, TPP, and APP‐TPP mixture flame retardant including composites were prepared by using extrusion and injection molding methods. The properties of the composites were determined by the tensile test, limiting oxygen index (LOI), differential scanning calorimetry (DSC), and heat release rate (HRR) test. The minimum Tg value was observed for the TPP including PLA/PC composites in DSC analysis. The highest tensile strength was observed in GF‐reinforced PLA/PC composites. In the LOI test, GF including composite was burned with the lowest concentration of oxygen, and burning time was the longest of this composite. However, the shortest burning time was obtained by using the mixture flame retardant system. The flame retardancy properties of GF‐reinforced PLA/PC composite was improved by using mixture flame retardant. When analyzed the results of HRR, time to ignition (TTI), and mass loss rate together, the best value was obtained for the composite including APP.  相似文献   
62.
Perovskite type La0.8Sr0.2Ga0.83Mg0.17O3 powders were prepared via simple polyol method for the first time in literature. Obtained material was characterized by using XRD, SEM, Impedance Spectroscopy and density measurements. Pure LSGM powders were achieved after heat treatment at 1100 °C for 12 h. 87% relative density was obtained after pressing of these powders under 1 MPa and sintering at 1250 °C for 12 h. Average particle size was calculated as 1.77–2.4 μm from SEM micrographs. Overall conductivity of the LSGM pellet was found to be 0.0014 S/cm at 850 °C with impedance analysis and showed that the preparation process needs improvements.  相似文献   
63.
Water Resources Management - Slit-check dams have a flow regulation function under normal flow conditions as well as holding large solid (debris flow control). However, the effects of such...  相似文献   
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Thirty volunteers who met criteria for generalized anxiety disorder received 12 sessions of training in progressive muscular relaxation. Sixteen of the clients also were given cognitive therapy during 10 of those sessions, and the remaining 14 received nondirective therapy. Therapy was provided by 16 graduate student clinicians. The group as a whole showed substantial reductions in anxiety as measured by psychiatric assessor ratings, questionnaires, and daily self-monitoring, although relaxation plus cognitive therapy produced significantly greater improvement than relaxation plus nondirective therapy on several pretherapy-posttherapy questionnaires. Relaxation-induced anxiety, as measured by a questionnaire after each relaxation session, was significantly related to improvement in the total group: Clients who became anxious during relaxation training showed the least improvement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Requirements engineering has been recognized as a fundamental phase of the software engineering process. Nevertheless, the elicitation and analysis of requirements are often left aside in favor of architecture-driven software development. This tendency, however, can lead to issues that may affect the success of a project. This paper presents our experience gained in the elicitation and analysis of requirements in a large-scale security-oriented European research project, which was originally conceived as an architecture-driven project. In particular, we illustrate the challenges that can be faced in large-scale research projects and consider the applicability of existing best practices and off-the-shelf methodologies with respect to the needs of such projects. We then discuss how those practices and methods can be integrated into the requirements engineering process and possibly improved to address the identified challenges. Finally, we summarize the lessons learned from our experience and the benefits that a proper requirements analysis can bring to a project.  相似文献   
68.
Many domains require scalable algorithms that help to determine diagnoses efficiently and often within predefined time limits. Anytime diagnosis is able to determine solutions in such a way and thus is especially useful in real-time scenarios such as production scheduling, robot control, and communication networks management where diagnosis and corresponding reconfiguration capabilities play a major role. Anytime diagnosis in many cases comes along with a trade-off between diagnosis quality and the efficiency of diagnostic reasoning. In this paper we introduce and analyze FlexDiag which is an anytime direct diagnosis approach. We evaluate the algorithm with regard to performance and diagnosis quality using a configuration benchmark from the domain of feature models and an industrial configuration knowledge base from the automotive domain. Results show that FlexDiag helps to significantly increase the performance of direct diagnosis search with corresponding quality tradeoffs in terms of minimality and accuracy.  相似文献   
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Two ferrocenyl‐substituted N‐acetyl‐2‐pyrazolines, N‐acetyl‐3‐(2‐furyl)‐5‐ferrocenyl‐2‐pyrazoline (Fc‐1) and N‐acetyl‐3‐(2‐thienyl)‐5‐ferrocenyl‐2‐pyrazoline (Fc‐2) electrospun fibers, were produced in the presence of plasma‐modified chitosan (PMCh)/poly(ethylene terephthalate) (PET) supporting polymers with an electrospinning method. The morphological and chemical characterizations of the PMCh/PET/Fc‐1 and PMCh/PET/Fc‐2 electrospun fibers were determined by scanning electron microscopy coupled with energy‐dispersive X‐ray spectroscopy analysis. Thermogravimetric analysis results indicated the presence of ferrocene within the PMCh/PET nanofibers. The electrochemical behavior of the PMCh/PET/Fc‐1 and PMCh/PET/Fc‐2 electrospun fibers were investigated by cyclic voltammetry measurements based on the ferrocene/ferrocenium redox couple. The new PMCh/PET/Fc‐1 and PMCh/PET/Fc‐2 electrospun fibers aggregated on the indium tin oxide were used for phosphate anion sensing. The highest oxidation peak currents were observed for the PMCh/PET/Fc‐1 electrospun fibers at about 0.56 V in 0.1M phosphate buffer. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43344.  相似文献   
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Iranian Polymer Journal - Mucoadhesive gel formulations containing pentoxifylline (PTX)-loaded nanoparticle (NP) for the treatment of genital ulcer were prepared and evaluated. In that context,...  相似文献   
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