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提出了一种N2O-C2H2火焰原子吸收光谱法进行热电池DEB(去极剂、电解质、粘合剂的复合片)中钙含量测定的新方法。介绍钙最佳测定条件以及呈良好线性范围的浓度。同时对样品的测定条件和干扰因素进行了综合考虑。该方法具有很好的灵敏度、干扰小、重现性好,准确度、精确度均能满足热电池研制工作的要求。测定样品含钙量相对标准偏差均小于1.0%(测定次数n =10)。标准加入回收率均在97%~102%(n =6)范围。结果表明:运用N2O-C2H2火焰原子吸收光谱法进行热电池DEB中钙含量的测定,完全适用于热电池DEB中钙含量的控制分析。达到了实验室分析质量控制的要求。 相似文献
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铜、铝导体生产的发展趋向及有关问题的探讨 总被引:4,自引:0,他引:4
本文综合分析了我国铜、铝及它们的合金导体在品种、质量和生产装备方面的现状和国外在该领域的进展及发展趋向,并指出:我国铜、铝导体的年用量已名列世界前茅,但导体的品种少,工艺装备落后。其中铝连铸连轧生产线比铜的更落后,主要差距在计算机监控系统,由此也限制了品种的发展;废铜在导体上的应用,要提高质量关键在于所用废铜原材料的级别、熔炼炉及熔炼工艺;铜杆质量不能满足电缆工业发展的需要,修订电工用铜杆国标或制订行业标准,实行铜杆分等使用已是势在必行;我国电缆工业需要建立真正意义上的从金属材料、镀层、导体结构到绝缘材料特种的电缆厂;行业协会在组织行业内部带有共性问题的科技攻关,与产业界、行业间的协调和科技合作方面应起到更大的作用;应发挥综合优势,加强材料、工艺、产品与设备的联合攻关,实现科技与生产的创新。 相似文献
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根据规划在黄河北干流上布置万家寨、龙口、天桥、碛口、古贤、甘泽坡6座水利枢纽工程。北干梯级开发可有效控制和管理黄河的水沙关系、洪水;改善生态环境,使水资源得到合理利用;向华北电网提供大量电力,对秦晋2省工农业、通航和旅游等具有促进作用,并带动地方经济的发展。 相似文献
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采用空气-乙炔(AIR-C2H2)火焰原子吸收光谱法对热电池加热粉中钾K的含量进行测定。介绍了K的最佳测定条件。同时对样品的处理条件和测定中的干扰因素在综合分析的基础上提出了有效的测定方案。该测定方法灵敏度好,准确度与精确度均能满足热电池研制工作的要求。测定出的样品K含量相对标准偏差均小于1.0%(测定次数n=10)。标准加入回收率均在97%~102%(n=5)范围内。测定结果表明,运用AIR-C2H2火焰原子吸收光谱法进行热电池加热粉中K含量的测定,适用于热电池加热粉中K含量的控制。 相似文献
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T. A. Rafalskaya 《Thermal Engineering》2017,64(4):313-317
The effect of deviations in heat network parameters on operation of heating system and hot-water supply systems in buildings is examined. The consequences of a decrease in the water temperature in a heat network under extreme weather conditions in a range below the design ambient air temperature, the efficiency of disconnection of a hot water supply system (HWSS) heater in this period, and deviations in the normal heat supply in the transition period at relatively high outdoor temperatures are considered. The specific and scope of failures depend on the design-heating load to design hot water supply load ratio for the heat network. A mathematical model was developed, and numerical investigation was performed of modern schemes of heat points which are designed primarily for covering the hot water supply load and recovering the heating system heat output in case of low or no hot water consumption in HWSS. The performed calculations demonstrate that the heating system has no time to restore its heat output, thereby considerably reducing air temperature in the heated premises. The lower the ambient air temperature and the lower the ratio of the design loads for hot water supply and heating, the greater is this decrease. At the same time, in case of a sudden decrease in the outdoor temperature and an accident in the heat supply system, the heating system must be the priority consumer, since a heating failure not only decreases the thermal comfort of consumers but can cause emergency situations in local utility systems, such as a cold water supply system. Correction of failures in a heat supply system requires calculation of operating conditions of heat networks. 相似文献
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The statistical characteristics of amplitude and amplitude-phase spectra of PDs in the insulation of model specimens with
artificial flaws in a semiconducting coating are investigated. The algorithm for distinguishing the flaws in the stator winding
insulation of high-voltage electrical machines based on statistical parameters of the PD spectra is developed and practically
implemented. 相似文献
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本文较详细的介绍了在合肥同步辐射实验室(NSRL)二期工程中的束团位置监测(BPM)电子学系统中对数比电路设计与应用。结合对数放大器自身的特性,介绍了此电路在BPM系统中的组成,工作原理,试验结果和参数的测量方法。 相似文献
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铅酸蓄电池板栅在均匀酸性介质中,一面的腐蚀情况为点状腐蚀,另一面为互相交错的网格形状,这个问题一直是化学界的未解之谜。本文通过分析铅酸蓄电池离子和电子在充/放电过程中的运动情况,发现放电反应中所生成的电子有很大的初速度,电子以这个速度从板栅一面飞向另一面,由于受到电场和初速度方向影响,形成了独特的腐蚀形态。此外,电子在放电过程中通过板栅时,并不是均匀的,而是有若干孤立的电子发射点,发射出的电子在对面的界面相互交叉和外界的干扰振动等,交叉区域的变化形成纵横交错的网格腐蚀。 相似文献
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A. I. Fedorov 《Thermal Engineering》2014,61(10):724-730
The damageability for water-wall tubes of an external salt compartment of a TPE-208 boiler is analyzed. The general cause for tube damage is the intensive underslime corrosion of the inner surface, which is caused by a local increase in the salt concentration in boiler water. The experiment-calculated method showed that continuous bleeding from an external cyclone being the first in water downstream causes a substantial increase in the concentration of salts (more than by a factor of three) and scale-forming agents within a contour of the loop of a distant cyclone in comparison with the variant of bleeding from a loop being the second in water downstream. 相似文献
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分析了常用的姆欧继电器在超高压电缆线路上应用的特殊性及可能存在的问题,并作了相应的仿真计算及验证。对于仿真中出现的问题提出了一些改进方法。并结合理论和仿真结果分析了电缆的电气参数特性给相间距离保护带来的影响。 相似文献
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When one solves engineering problems related to the cooling of fuel assemblies (FAs) in a spent fuel storage pool (SFSP) and the assessment of nuclear safety of FA storage in an SFSP in the initial event of loss of SFSP cooling, it is essential to determine the coolant density and, consequently, steam volume fractions φ in bundles of fuel elements at a pressure of 0.1–0.5 MPa. Such formulas for calculating φ that remain valid in a wide range of operating parameters and geometric shapes of channels and take the conditions of loss of SFSP cooling into account are currently almost lacking. The results of systematization and analysis of the available formulas for φ are reported in the present study. The calculated values were compared with the experimental data obtained in the process of simulating the conditions of FA cooling in an SFSP in the event of loss of its cooling. Six formulas for calculating the steam volume fraction, which were used in this comparison, were chosen from a total of 11 considered relations. As a result, the formulas producing the most accurate values of φ in the conditions of loss of SFSP cooling were selected. In addition, a relation that allows one to perform more accurate calculations of steam volume fractions in the conditions of loss of SFSP cooling was derived based on the Fedorov formula in the two-group approximation. 相似文献
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压实度标准制定的合理性 总被引:5,自引:0,他引:5
通过土料干湿法对比试验和环刀取土尺寸效应对比试验, 探讨了影响分层碾压土基垫层
压实度的主要因素, 指出通过击实试验制定土基压实度标准和施工质量检验时应注意的问题, 以及如何确保压实度标准制定的合理性和现场检验的客观性。 相似文献
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文章介绍了2008年冰灾及汶川地震后国家对提高电力系统抗灾能力的新规定,以及2011年国务院《电力安全事故应急处置和调查处理条例》对电网运行的新要求;对湖北电网规划目标和原则进行补充探索,提出目标电网安全性扫描方法,为今后的电网滚动规划提供依据。 相似文献
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BP神经网络对模式识别是最具优势的,用它对发电机失磁保护的有功转子判据动作区进行识别,并将结果与传统的微机保护中用直线近似代替的动作区进行比较,结果证明了神经网络方法的准确性和优越性。 相似文献
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G. S. Zinoviev 《Russian Electrical Engineering》2011,82(6):332-336
Based on the author’s direct calculation methods of power-producing processes, new quality indicators of nonsinusoidal voltages
and currents in the form of integral and differential coefficients of harmonics of voltage and current have been obtained.
The advisability of introducing them into the standards for the quality of the power network voltage and the consumption current,
as well as also into the method for calculating of the partial participation of the consumer and the power supply system in
the change in the overall quality of the electric energy has been shown. 相似文献