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1.
分叉型海湾温水排放数学模型   总被引:2,自引:0,他引:2       下载免费PDF全文
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   
2.
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   
3.
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   
4.
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   
5.
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   
6.
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   
7.
The nano-crystalline La_(0.1)Bi_(0.9)FeO_3 compound was successfully synthesized by starch-based combustion method. The crystal structure and magnetic behavior were studied by temperature-dependent X-ray diffraction(XRD), scanning electron microscopy(SEM), differential scanning calorimetry(DSC) and magnetic measurements. The La_(0.1)Bi_(0.9)FeO_3 compounds crystallized in a rhombohedrally distorted perovskite structure with space group R3 c. The substitution of La for Bi reduced the rhombohedral distortion. The structural phase transitions in La_(0.1)Bi_(0.9)FeO_3 driven by temperature showed that the extraordinary two-phase coexistence state of BiF eO 3 and LaF eO 3 was observed in a narrow temperature range of 630–700 oC. The magnetization of the La_(0.1)Bi_(0.9)FeO_3 sample was improved by heat treatment in the temperature range. When the heat treatment temperatures rose from 25 to 600 oC, the remanence(Mr) and coercivity(Hc) of the La_(0.1)Bi_(0.9)FeO_3 compound almost remained the same, and increased rapidly to 0.134 emu/g and 7.1 KOe on further increasing the heat treatment temperature to 650 oC.  相似文献   
8.
南河是汉江中游洪水的主要来源,南河上的三里坪和寺坪水库对控制汉江中下游洪水有重要作用,对两水库预留防洪库容、防洪调度方案及其防洪效果进行了分析.  相似文献   
9.
孤山水电站库区白河县老城区临汉江的街道人口密集、移民安置困难。为了在保证防洪调度安全的同时,提高发电经济效益,结合上下游水库的调度运行方式,分析了孤山水电站汛期预泄调度方式的制约因素。选取了5个典型历史洪水过程,在研究库区防洪运行控制水位、预泄调度时机的基础上,拟定了汛期调度方式,并对发电和航运效益的影响进行了分析。所提出的调度方式可在一定程度上缓解水利水电开发与该地淹没损失的矛盾。  相似文献   
10.
介绍了下浒山抽水蓄能电站工程概况,回顾了我国抽水蓄能电站发展历程,分析了下浒山抽水蓄能电站对华东电网和安徽电网的作用,解读了工程所在"长三角"城市群新时期经济发展需求、国家法律法规和产业政策及我国电力发展"十三五"规划。总结认为,下浒山抽水蓄能电站具有独特的区位优势,工程技术经济指标较优,面临不可多得的工程建设机遇,建议安徽有关部门尽早推进项目前期立项工作,争取纳入华东电网2030年以后选点规划。  相似文献   
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