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传统的大学生教育实践活动只是定义在一个短时段的集中实习培训上,活动与实践面狭窄,不能适应新课程理念下新型中学教师的培养。在改革与实践的基础上,提出了化学专业教育见习常态化、岗前培训规范化、基地活动系统化、教育资源共享化、实践总结长效化的教育实践基地协同运行模式,通过协同运行实践操作,使基地双方教师的教学科研水平和指导能力不断提高,使实习学生的从教能力得到全面发展和提升。 相似文献
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档案信息化管理对于保障产科教融合协同育人实训平台动态复杂体系的正常运行和实训教学的有效实施具有重要意义。以青岛大学材料学科实训平台为例研究了实训平台动态运行复杂体系档案信息化管理存在的问题与对策。结果显示:实训平台动态复杂体系实现档案信息化管理存在档案信息组成元素的复杂性、档案信息收集与整理的多样性和时效性、对档案信息管理机制的强依赖性等问题;实现实训平台动态复杂体系档案信息化管理的对策有:准确梳理复杂体系各档案元素之间的关系、设计合理的档案信息管理系统、科学构建服务于实训教学的档案管理机制。 相似文献
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A stochastic model is developed to predict the periodic operation per formance of the continuous counter-current adsorption process.The model takes into account the effects of random backmixing of particles,axial dispersion of liquid phase,liquid-film mass transfer,intraparticle diffusion and particle shape,and can reveal clearly the behavior of solid and liquid phase in adsorption process.The simulation results agree with the experimental data rather well. 相似文献
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NG Seik Weng 《结构化学》2014,(2):294-303
The first part of this report describes the data reduction of non-merohedrally twinned crystals measured on Bruker and Agilent area-detector diffractometers. The image frames of methyl-2-aminopyrazine-3-carboxylate were processed with APEX2 to furnish a set of overlapping diffraction indices that were used for solution and refinement. CrysAlisPRO was used for processing the frames of bis(diethyldicarbamato)nickel, which exists in monoclinic and tetragonal polymorphs, and in untwinned and twinned forms. In the second part, the crystal structure of [(3-formyl-4- hydroxyphenyl)methyl]triphenylphosphanium chloride was refined through the ‘HKLF 5'(based on a combined set of diffraction indices) and PLATON(based on one set of diffraction indices) routes to give identical outcomes because the amount of overlap of the twin domains is small. For the third part, in a proof-of-concept investigation, the diffraction pattern of untwinned and twinned 4-{(E)-(4-aminophenyl)diazenyl]phenylamine was recorded simultaneously in one run; the three domains could be indexed and the crystal structure satisfactorily refined. The refinement was identical to those derived from independent measurements; the crystal structure features two independent centrosymmetric molecules, one of which is ordered and the other whole-molecule-disordered. This two-in-one run opens up the possibility that two or more crystals having different atomic compositions can be measured simultaneously if their reciprocal lattices do not overlap significantly. 相似文献
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通过分析电化学阻抗(EIS)在质子交换膜燃料电池(PEMFC)动态应用,本文指出制约EIS 工具发展的瓶颈问题. EIS 高频电阻确定电池内阻已成普遍方法,但仅在小电流电池可以应用;低频分析因涉及物质传输仍是难点和重点;EIS 改进型Randles 等效电路分析已初步建立,并深入至物质传输-反应、电池操作/衰减、高温电池研究;EIS 正发展为电堆分析工具、电动汽车控制核心. 然而多学科交叉的暂态EIS 发展,仍是前沿突破难点. 相似文献
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固体氧化物燃料电池(Solid Oxide Fuel Cell, SOFC)是一种清洁高效的能源转化装置, 如何提高SOFC的发电效率, 并保证阳极不发生局部氧化, 是工业界与学术界的焦点问题之一. 建立了工业尺寸SOFC的效率测试与评价方法, 通过对比多组高燃料利用率下的电池效率测试结果, 发现在相同燃料利用率下, 电压会随电流的增大而下降. 因此, 较低的电流有利于达到更高的效率, 较大的电流则有利于输出更高的功率. 此外, 研究了高燃料利用率下放电时电压波动与阳极局部氧化的关联, 通过分析阳极Ni的临界氧化条件, 提出了避免发生阳极局部氧化的电池安全运行条件: 电池的输出电压应高于Ni的临界氧化电动势. 基于所采用的电池和测试参数, 发现在各个电流及温度下, SOFC发电效率大于50%时, 对应的燃料利用率一般在77%~90%这一区间内, 当燃料利用率为87.10%时, 电池具有最大的发电效率. 尽管对于不同材料、结构和制备工艺的SOFC, 其最高效率所对应的工况会有所差异, 但所提出的效率测试及评价方法和阳极安全运行的判断条件具有一定的普适性, 可以根据实际需求中高功率、高效率及长期稳定运行的重要程度, 确定相应的高效及阳极安全运行条件. 相似文献
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准东高碱煤气化过程中碱金属迁移与结渣特性实验研究 《燃料化学学报》2015,43(8):906-913
利用循环流化床对天池木垒高碱煤进行了气化实验研究,获得了天池木垒高碱煤在循环流化床上的结渣特性及碱金属迁移规律,并对实验中出现的床内颗粒聚团现象进行了分析。结果表明,不同存在形态的碱金属在煤气化过程中的迁移规律不同,水溶钠和醋酸铵溶钠在煤气化过程中以气态形式析出,不溶钠主要存在半焦中;随着气化温度升高,底渣和煤气中钠含量增加,飞灰中钠含量减少;尾部管道温度降低过程中,煤气中钠的冷凝速率明显高于钾;天池木垒高碱煤气化过程中容易引起床内颗粒聚团,床温越高,颗粒聚团现象越明显,床温波动越大;碱金属与灰分中矿物成分及床料中SiO2反应生成黏性低温共熔物是导致颗粒聚团的关键。 相似文献
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Simin Nazari Mosadegh Keshavarz Bahador Karami Nasir Iravani Masoumeh Vafaee-Nezhad 《中国化学快报》2014,25(2):317-320
Imidazol-1-yl-acetic acid is introduced as a new, efficient and recyclable green bifunctional organocatalyst for the synthesis of 1,8-dioxooctahydroxanthenes under solvent-free conditions. This catalyst is water soluble and can be separated from the products by simple filtration. The filtrate can be evaporated to dryness and recrystallized from cool methanol to give the recovered catalyst. This organocatalyst was used for the synthesis of 1,8-dioxooctahydroxanthenes under solvent-flee conditions and recycled up to 8 consecutive runs without any losing of its efficiency. 相似文献
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PPT课件运行的窘境及解决方法 总被引:2,自引:0,他引:2
目前,PPT因为简单、便捷而成为制作课件的首选软件。但是纵观众多的PPT课件,笔者发现它与Flash动画、视频等整合得不是很好,在运行时会遇到以下的一些窘境。下面就分述PPT课件运行的窘境及解决方法。 相似文献