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41.
Background: Growing interest in the use of the less-explored bottom spray technique for fluidized bed granulation provided impetus for this study. Aim: The impact of fluid dynamics (air accelerator insert diameter; partition gap) and wetting (binder spray rate) on granule properties were investigated. Method: In this 33 full factorial study, the results were fitted to a quadratic model using response surface methodology. The air velocity at the spray granulation zone for the investigated conditions was measured using a pitot tube. Results: Air accelerator insert diameter correlated to measured air velocity at the spray granulation zone and was found to not only dictate growth but also influence granule morphology. The partition gap was found to play important roles in regulating particle movement into the spray granulation zone and optimizing process yields, whereas binder spray rate significantly affected granule morphology but not granule size. Conclusions: Unlike conventional fluidized bed granulation, ease of modulation of fluid dynamics and insensitivity of the bottom spray process to wetting allow flexible control of granule size, shape, and flow. Its good drying ability also indicated potential use in granulating moisture-sensitive materials.  相似文献   
42.
Collective decision making involves on the one hand individual mental states such as beliefs, emotions and intentions, and on the other hand interaction with others with possibly different mental states. Achieving a satisfactory common group decision on which all agree requires that such mental states are adapted to each other by social interaction. Recent developments in social neuroscience have revealed neural mechanisms by which such mutual adaptation can be realised. These mechanisms not only enable intentions to converge to an emerging common decision, but at the same time enable to achieve shared underlying individual beliefs and emotions. This paper presents a computational model for such processes. As an application of the model, an agent-based analysis was made of patterns in crowd behaviour, in particular to simulate a real-life incident that took place on May 4, 2010 in Amsterdam. From available video material and witness reports, useful empirical data were extracted. Similar patterns were achieved in simulations, whereby some of the parameters of the model were tuned to the case addressed, and most parameters were assigned default values. The results show the inclusion of contagion of belief, emotion, and intention states of agents results in better reproduction of the incident than non-inclusion.  相似文献   
43.
花儿 《山东化工》2014,43(12):146-147
阐明了过去三年,本校化工学院制药工程专业毕业实习单位的开拓工作及不同途径毕业实习给学生的就业带来的机遇和效果。探讨了制药工程专业毕业实习教学体系改革的内容和基本思路,进一步研究了毕业实习的方法和改革、实习基地建设的重要性。即,扩大毕业实习内容及范围,将毕业实习与就业相结合,从而提高毕业生的独立意识和社会活动能力,使其成为受企业欢迎的高素质、应用型人才。  相似文献   
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45.
Thermal behavior, structural properties, and phase equilibria of the (100−x)TeO2-xNa2O system were studied in the 5 ≤  50 mol% composition range. Investigation of glass formation behavior in the binary system was realized, and the glass formation range was determined as 7.5 ≤  40 mol%. Differential thermal analysis (DTA) and Fourier transform infrared (FTIR) spectroscopy techniques were used for thermal and structural characterization of the glasses. Influence of Na2O content on glass transition temperature (Tg), glass stability (∆T), density (ρ), molar volume (VM), oxygen molar volume (VO), and oxygen packing density (OPD) values of sodium tellurite glasses was evaluated considering the structural transformations in the glass network. For the phase equilibria studies, DTA, X-ray diffraction (XRD), and scanning electron microscopy/energy dispersive X-ray (SEM/EDS) techniques were utilized to characterize the heat-treated samples. According to the phase equilibria studies, three eutectic regions were detected in the 0 < < 50 mol% composition range of the (100−x)TeO2-xNa2O system. A new invariant endothermic reaction was detected for the compositions between 40 ≤  45 mol%. Na2O.8TeO2 (11.11 mol% Na2O) compound that was claimed to exist in the binary system in the literature was found to be the metastable δ-TeO2 phase.  相似文献   
46.
The vacuum pressure swing adsorption (VPSA) method, as an alternative way to separate the CH4/N2 mixture, was adopted to purify methane from coal mine methane. The performance of the VPSA process was investigated experimentally and theoretically with a reactivated carbon molecule sieve as the adsorbent. The computer calculations were compared to the experimental data. The concentrated methane with 79% purity could be collected directly during the high-pressure adsorption step with 93% recovery and 0.0720 mL·g–1·min–1 productivity, when the composition of raw gas was 10/90 vol% CH4/N2, which is of great significance for the utility of low quality energy gas.  相似文献   
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48.
为了掌握铜线拉拔过程铜线的变形规律及其不同模具对拉拔过程的影响,通过对拉丝模具几何尺寸和铜线塑性变形的受力分析,建立拉拔变形模型并利用DEFORM-3D有限元对拉拔过程进行模拟,求解不同模角参数下铜线应力应变场和损伤场的变化规律,获得最佳的拉拔模角参数,减少模具磨损延长了模具寿命;同时分析了不同拉丝速度下铜线的变形规律,优化了拉丝工艺参数。  相似文献   
49.
利用CALPHAD技术全面评估了BaO-SrO-TiO2-ZrO2体系中BaO-SrO-TiO2三元子系统,提供了一系列的计算相图。在计算相图的指导下获得了制备性能优良的微波介电陶瓷材料的成分配比。  相似文献   
50.
石尔  衣晓青  傅俊萍 《广州化工》2014,(19):170-171,230
以教学实践为基础,结合能源动力类专业基础课课程的教学特点,深入探讨创新型人才培养背景下参与式教学在《热工理论基础》系列课程中应用的设计理念、实施策略、实践过程及其结果,结果表明参与式教学对于提高学生学习兴趣、自主能力和创新能力起着积极地作用,探索出了行之有效的工科专业基础课参与式教学模式。  相似文献   
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