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A semi-empirical calculation of the heat of formation was applied to ternary system:La-Fe-Al,Fe-Ni-V and Cu-Pd-Si.The calculated values were compared with the experimental ones andthe coincidence was satisfactory.This method is helpful to predict the stabilities of ternary compounds andsolid solubility. 相似文献
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采用正交边界拟合坐标变换模拟复杂的边界,全隐式耦合模型离散基本方程,矩阵追赶法求解代数方程组,建立了分叉型海湾温水排放数学模型.算例表明,包络图的方法评价温升影响范围,能够为工程设计和环境评价提供依据. 相似文献
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The effect of rapid solidification on structure and electrochemical performance of the LaNi4.5Co0.25Al0.25 hydrogen storage alloy was investigated by X-ray powder diffraction and a simulated battery test, including maximum capacity, cycling stability, self-discharge, and high-rate discharge ability (HRD). All the melt-spun alloys were single-phase with the CaCu5-type structure (space groupP6/mmm). In comparison to the as-cast alloy, the rapidly quenched alloys manifested an improved homogeneity of com-position and expanded lattice parameters. The electrochemical measurements showed that the activation property, cycling stability and self-discharge of the alloy electrodes were also improved for the rapid solidified alloys. The HRDof the as-cast alloy was better than those of all the rapidly solidified alloys. As the quenching rate increased, the HRD and exchange current density first decreased and then increased. 相似文献
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The structure, magnetic and electric properties of Sr2FeMoO6 (the as-made sample) and samples after heat treatment were investigated. The nuclear and magnetic structures of the samples were studied using neutron powder diffraction at room temperature. The results show that the tunneling magnetoresistance of polycrystalline Sr2FeMoO6 depends on its annealing temperature. Annealing at 800 ℃ makes the minimal magnetoresistance(MR) elevated, which may be due to the change of the grain size or the modified intergranular connections. Because of the impurity phase of Fe which probably affects the magnetotransport properties is much larger in sample C, so the MR is decreased by postannealing at 1100 ℃. Therefore, further enhancement of the tunneling magnetoresistance (TMR) can be realized by regulating the grain size at appropriate annealing temperature. 相似文献
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乌东德、白鹤滩水库投运后,长江上游水库群联合防洪调度为进一步提高三峡水库对城陵矶防洪补偿控制水位创造了有利条件。为提高三峡水库对城陵矶防洪补偿控制水位,针对金沙江下游梯级防洪库容投入运用条件,基于三峡坝址不同典型年的不同频率设计洪水,开展了荆江防洪和库区回水风险分析,提出了金沙江下游梯级配合三峡水库的等比例分级拦蓄方式,在确保荆江及库区防洪安全的前提下,提出了三峡水库对城陵矶防洪补偿控制水位优化运用方案,给出了金下梯级预留防洪库容与三峡水库对荆江防洪库容的等效关系。研究结果表明:提出的等比例分级拦蓄方式综合了拦量和削峰两种模式,有效利用了金下梯级防洪库容,调度效果最好;提出的水位优化运用方案具备较好的防洪减灾效果,丰富完善了长江上游水库群联合防洪调度方案,可进一步减少中下游超额洪量。研究成果可为长江水库群实际洪水调度提供技术支撑和决策参考。 相似文献
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城陵矶地区是长江中下游洪灾最频发的区域之一,是长江水库群防洪的重点保护对象。金沙江下游乌东德、白鹤滩、溪洛渡、向家坝4座梯级水库与三峡水库组成的巨型水库群防洪能力巨大,显著改变了流域防洪调度格局。在概括分析城陵矶地区防洪需求,回顾三峡水库对城陵矶地区防洪补偿控制水位不同阶段成果的基础上,剖析了优化防洪补偿控制水位的研究要点,研究了金沙江下游梯级防洪库容投入情况,进而明确了提高防洪补偿控制水位的有利条件。研究结果表明:在三峡水库水位达到城陵矶防洪补偿控制水位158.00 m后,金沙江下游梯级水库在预留40.93亿m3防洪库容的基础上,尚有30亿~60亿m3富余防洪库容可配合运用,为进一步提高三峡水库对城陵矶防洪补偿控制水位创造了良好条件。 相似文献
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介绍了厄瓜多尔的水力资源总量及其分布情况,并对水力资源开发利用过程中存在的主要问题进行了剖析。基于厄瓜多尔电力需求预测及电源发展规划,结合该国区位优势及安第斯共同体电力联网战略,对厄瓜多尔国内、国际电力市场发展空间进行了论述。以已有的水电站规划成果为基础,对所推荐的具有开发价值的重点水电项目进行了分析研究,同时结合不同的规划水平年电力市场情况及重点水电项目的地理位置、交通条件及其前期工作深度,提出了相应的开发时序初步构想,以期为我国的能源企业实施"走出去"战略、深入开拓厄瓜多尔水电市场提供决策与参考。 相似文献
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BaB_2O_4-BaF_2相图的测定和计算SCIEI 总被引:1,自引:0,他引:1
为寻求生长β-BaB_2O_4单晶体的合适助熔剂,本文用DTA和X射线衍射法测定了BaB_2O_4-BaF_2二元相图。通过对实测相图的优化分析,获得了该二元系的有关热力学函数,并计算了该二元相图。计算与实测结果吻合很好。该体系有一同份熔化化合物BaBO_2F,熔点为867℃,化合物与BaB_2O_4和BaF_2共晶反应的温度和成分分别为749.1℃,40.7mol%BaF_2和815.4℃,57.2mol%BaF_2。研究表明,BaBO_2F是生长β-BaB_2O_4可能的助熔剂。 相似文献