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101.
介绍了平圩第二发电公司3号机组由北重阿尔斯通公司制造的首台超临界600 MW汽轮机的主要技术特点,并对机组性能考核试验的热耗率、出力及缸效率等试验结果进行了分析.机组的热耗率为7 463.5 kJ/(kW·h),经济性居于国内领先水平.  相似文献   
102.
海底电缆线路铺设复杂,当线路出现故障时,很难定位故障的准确位置,电力线路故障点的快速定位是加快电力线路修复、减少停电时间的关键。在分析架空线和海缆故障特征的基础上,提出一种适用于海缆混合线路的故障定位系统。该系统通过故障区段定位装置就地采集海缆两侧的电流,就地进行故障区段定位,并将区段定位的结果通过光纤发送给线路两侧的保护装置。当判断出故障在电缆上时,立即闭锁线路两侧保护装置的重合闸功能。保护装置集成了行波测距模块,在收到区段定位信号的基础上进行适用于混合线路的双端行波测距。大量的仿真测试表明,提出的适用于混合线路的故障定位系统能够实现对混合线路的故障区段精准定位,使混合线路的自适应重合闸应用成为可能;在区段精准定位的基础上能够对混合线路的故障点进行精确定位,可以缩短停电时间,提高供电的可靠性。  相似文献   
103.
在煤层气勘探开发井全井段采用岩屑录井,在参数井目的层段采用岩屑录井和岩芯录井,并根据钻时、气测等其它录井资料进行综合分析,准确地判断钻遇地层和岩性,卡准了层位,准确、齐全地录取了各项地质资料。为在煤层气勘探开发减少投资、加快勘探开发速度、增加投资效益、降低安全钻进风险积累宝贵经验。  相似文献   
104.
AlGaN/GaNHEMT器件研究   总被引:4,自引:0,他引:4  
叙述了AlGaN/GaN HEMT的特点及制造工艺,给出其测试结果,最大跨导 ̄157ms/mm,由S参数测量扒出器件的截止频率fr和最高振荡频率fmax分别为12GHz和24GHz。  相似文献   
105.
This paper discussed in detail about the BEE component and the characteristics of the different kinds of attapulgite clay ores as well as basalts, weathered basalts in four localities of attapulgite clay deposits of Jiangsu and Anhui Provinces of China. It is concluded that the half-weathered basalts have not distinct REE fractionation and strong weathered basalts have HREE loss in the process of the basalts weathered to form smectite group minerals. And the latefitic montmorillonite clays that formed from the basalts weathering have a distinct Ce positive anomaly, a little MREE loss and LREE and HREE renew enrichment. That reflects the particular oxidation condition in the Earth‘‘ s surface and the adsorption of the colloid solution of the lake water in the basin of the continent in the time of the clays formed. The attapulgite clays produced by the reaction between basahs with lake water in the original place of the basin have same REE characteristics as that of the basalts and the weathered basahs. This shows that REE does not transfer heavily in the progressive chemical weathering process. The sedimentary attapulgite clays have also a similar REE component and characteristic parameters to the basalts and the weathered basalts, and have a distinct Eu negative anomaly and a big value of LREE/HREE, which shows that the sedimentary clay came from the weathered basalts, and BEE partitioning patterns characters of the clays are controlled by the residual material of the weathered basalts.  相似文献   
106.
The compositions of REE in quartz and pyrite from the main stage of the Laowan gold deposit in Henan Province and that in quartz from Laowan granite were determined by inductively coupled plasma-mass-spectrometry (ICP-MS) to trace the source of ore-forming materials. Meanwhile, the REE compositions of the deposit ore, granite and metamorphic wall rock were also considered for comparative studies in detail. The range of ∑REE of quartz and pyrite from the deposit ores is 4.18×10-6~30.91×10-6, the average of ∑REE is 13.39×10-6, and the average of ∑REE of quartz in the Laowan granite is 6.68×10-6. There is no distinct difference of REE parameters between the deposit ore quartz and granite quartz. The quartz in gold deposit has the same REE particular parameters as quartzes from Laowan granite, such as δEu, δCe, (La/Yb)N and (La/Sm)N, partition degree of LREE to HREE, especially, the chondrite-normalized REE patterns, but no similarity to those from metamorphic wall rock, which shows that ore-forming hydrothermal fluid is mainly the fluid coming from the Laowan granite magma, rather than metamorphic fluid. Meanwhile, comparison studies on REE features between minerals from the deposit ores and related geological bodies in the deposit show that REE characteristics of minerals can serve as an indicator of ore-forming fluid properties and sources, while the REE characteristics of the bulk samples (such as deposit ores, granites and wall rocks) can not trace the source of the ore-forming materials exactly.  相似文献   
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