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991.
Amir Nader; Coles Meredith E.; Brigidi Bartholomew; Foa Edna B. 《Canadian Metallurgical Quarterly》2001,110(1):76
Understanding memory processes in social anxiety is important because these individuals often report negative memories of anxiety-provoking situations and because of the recent emphasis on learning and memory in models of anxiety. The authors examined the effect of learning on memory for negative social, positive social, and nonsocial information using the retrieval-induced forgetting paradigm in individuals with generalized social phobia (GSPs) and in nonanxious controls (NACs). Words were presented in 1 of 3 practice conditions: practiced words from a practiced category, unpracticed words from a practiced category, and unpracticed words from an unpracticed category. GSPs and NACs showed the same patterns of memory for practice categories for positive social and nonsocial words. However, for negative social words, GSPs benefited less from practice and were hurt less from the effect of practicing competing negative social information than were NACs. This pattern of processing may hamper GSPs' learning of, and habituation to, negative social information. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Adam A. Dundas Valentina Cuzzucoli Crucitti Simon Haas Jean‐Frdric Dubern Arsalan Latif Manuel Romero Olutoba Sanni Amir M. Ghaemmaghami Paul Williams Morgan R. Alexander Ricky Wildman Derek J. Irvine 《Advanced functional materials》2020,30(36)
A flow‐focusing microfluidic device is used to produce functionalized monodisperse polymer particles with surface chemistries designed to control bacterial biofilm formation. This is achieved by using molecularly designed bespoke surfactants synthesized via catalytic chain transfer polymerization. This novel approach of using polymeric surfactants, often called surfmers, containing a biofunctional moiety contrasts with the more commonly employed emulsion methods. Typically, the surface chemistry of microparticles are dominated by unwanted surfactants that dilute/mask the desired surface response. Time of flight secondary ion mass spectrometry (ToF‐SIMS) analysis of particles demonstrates that the comb‐graft surfactant is located on the particle surface. Biofilm experiments show how specifically engineered surface chemistries, generated by the surfactants, successfully modulate bacterial attachment to both polymer films, and microparticles. Thus, this paper outlines how the use of designed polymeric surfactants and droplet microfluidics can exert control over both the surface chemistry and size distribution of microparticle materials, demonstrating their critical importance for controlling surface‐cell response. 相似文献
993.
Liu Xu Tian Guangdong Fathollahi-Fard Amir Mohammad Mojtahedi Mohammad 《Clean Technologies and Environmental Policy》2020,22(2):493-512
Clean Technologies and Environmental Policy - The pollution and emission caused by the manufacturing, operation, and scrapping of marine ships have considerable impact on the environment.... 相似文献
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Amir Abdolmaleki Sedigheh Borandeh 《Polymer-Plastics Technology and Engineering》2015,54(10):1002-1008
Silver nanoparticles were obtained in novel optically active poly(amide-benzimidazole-imide) (PABI) matrix through an in situ procedure. Chiral PABI was prepared by polycondensation of amino acid based diacid and benzimidazole containing diamine in the presence of molten tetrabutylammonium bromide. Synthesized PABI was characterized by several techniques, including Fourier transform infrared spectra, 1H-NMR, elemental analysis, X-ray diffraction, thermogravimetric analysis and field emission scanning electron microscopy (FE-SEM). Then, PABI/Ag nanocomposite was fabricated based on metal complexation route for preparing silver nanoparticles in the PABI matrix and was characterized by various techniques. Microscopic images revealed good dispersion of Ag nanoparticles in the polymer matrix. 相似文献
996.
Seyyed Soheil Sadat Hosseini Ali Jafarnejad Amir Hossein Behrooz Amir Hossein Gandomi 《Expert systems with applications》2011,38(6):6556-6564
The optimal utilization of multiple combined heat and power (CHP) systems is a complex problem. Therefore, efficient methods are required to solve it. In this paper, a recent optimization technique, namely mesh adaptive direct search (MADS) is implemented to solve the combined heat and power economic dispatch (CHPED) problem with bounded feasible operating region. Three test cases taken from the literature are used to evaluate the exploring ability of MADS. Latin hypercube sampling (LHS), particle swarm optimization (PSO) and design and analysis of computer experiments (DACE) surrogate algorithms are used as powerful SEARCH strategies in the MADS algorithm to improve its effectiveness. The numerical results demonstrate that the utilized MADS–LHS, MADS–PSO, MADS–DACE algorithms have acceptable performance when applied to the CHPED problems. The results obtained using the MADS–DACE algorithm are considerably better than or as well as the best known solutions reported previously in the literature. In addition to the superior performance, MADS–DACE provides significant savings of computational effort. 相似文献
997.
Ali Gheidi Masoud Mirtaheri Amir Peyman Zandi Pejman Alanjari 《The Structural Design of Tall and Special Buildings》2011,20(6):700-710
The nonlinear response of buildings has attracted a tremendous amount of attention in recent years. Braces, as lateral force‐resisting elements of a structure, are designed to not only react in the elastic region, but also to exhibit nonlinear response beyond the elastic limit. However, buckling in compression drastically degrades the performance of braces under earthquake loading. Buckling restrained braces (BRBs) have been evolved into very effective systems for severe seismic applications. They prevent buckling in compression through the encasing of core steel into a steel tube and confining infill concrete. The effect of infill material is investigated in this research through the use of experimental tests. Filler material may be concrete, grout or mortar, as well as granular material such as compacted aggregate. Moreover, lightweight concrete or lean concrete may be utilized as filler to reduce the overall structural weight. Furthermore, the need for unbonding material may not arise when sand and gravel mixture is used. Nevertheless, the strength of the aggregate should be such that no buckling or strength deterioration is observed. Parametric studies on BRB characteristics are carried out in this research. Results of cyclic loading tests are then provided for individual cases to characterize the effect of response parameters of BRB assemblages. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
998.
Nourouddin Sharifi Theodore L. Bergman Amir Faghri 《International Journal of Heat and Mass Transfer》2011,54(19-20):4182-4192
A numerical model for simulating the melting of a phase change material (PCM) housed within an internally-finned metal enclosure is developed. A finite volume approach, utilizing the temperature-transforming model for phase change, is used to predict the conjugate heat transfer in the cavity walls and fins, as well as within the molten PCM. The influence of the number of fins, the fin length and thickness, and the hot wall temperature on the melting process is reported. With horizontal fins, rapid melting occurs during the early stages of the phase change, followed by a second, slow melting regime. Analytical correlations are developed that can be used to quickly estimate melting rates during both melting regimes, and it is shown that the predictions of the correlations are in good agreement with those of the detailed model. 相似文献
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