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在电流及温度分布满足“不变性”原理的基础上,本文分析了等离子体中心热区的能量平衡,求出了电子热传导系数,根据实验数据拟合出HL-1装置电子热传导系数的定标关系为X_e=6.8(n_(eq1))~(-1.2)。此关系与其他托卡马克装置的结果类似。 相似文献
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Copper‐Catalyzed NH Insertion and Oxidative Aromatization Cascade: Facile Synthesis of 2‐Arylaminophenols 下载免费PDF全文
Dong Ding Xiaobing Lv Dr. Jian Li Guangyang Xu Dr. Bing Ma Prof. Dr. Jiangtao Sun 《化学:亚洲杂志》2014,9(6):1539-1542
A copper‐catalyzed cascade reaction of N‐H insertion and oxidative aromatization has been developed. 2‐Arylaminophenols have been prepared in moderate to high yields from the diazo substrates. Moreover, this newly established methodology allows efficient access to natural 1‐oxygenated carbazole alkaloids, such as glycozolicine and murrayafoline A. 相似文献
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Gold(I)‐Catalyzed Diazo Coupling: Strategy towards Alkene Formation and Tandem Benzannulation 下载免费PDF全文
Daming Zhang Guangyang Xu Dong Ding Chenghao Zhu Dr. Jian Li Prof. Dr. Jiangtao Sun 《Angewandte Chemie (International ed. in English)》2014,53(41):11070-11074
A gold(I)‐catalyzed cross‐coupling of diazo compounds to afford tetrasubstituted alkenes has been developed by taking advantage of a trivial electronic difference between two diazo substrates. A N‐heterocyclic‐carbene‐derived gold complex is the most effective catalyst for this transformation. Based on this new strategy, a gold(I)‐initiated benzannulation has been achieved through a tandem reaction involving a diazo cross‐coupling, 6π electrocyclization, and oxidative aromatization. 相似文献
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在辐射的探测与测量中,精确的效率刻度是绝对强度测量必不可少的步骤。本工作是为研究磁约束聚变装置(托卡马克)在放电过程中的逃逸电子成分及硬X射线绝对辐射强度而作的实验准备工作。 相似文献
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针对KT-5C托卡马克装置等离子体的射频离子回旋波加热实验,本文给出一种回路天线负载阻抗的简便测量方法和测量结果。该方法的特点是,只涉及射频电流相对比值的测量,不要求专用设备,因此使物理量的标定、数据记录和处理都变得简单易行。 相似文献
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Stereodivergent Synthesis of N‐Heterocycles by Catalyst‐Controlled,Activity‐Directed Tandem Annulation of Diazo Compounds with Amino Alkynes 下载免费PDF全文
Kai Liu Chenghao Zhu Junxiang Min Dr. Shiyong Peng Guangyang Xu Prof. Dr. Jiangtao Sun 《Angewandte Chemie (International ed. in English)》2015,54(44):12962-12967
A stereodivergent synthesis of five‐membered N‐heterocycles, such as 2,3‐dihydropyrroles, and 2‐methylene and 3‐methylene pyrrolidines, has been developed through a tandem annulation of amino alkynes with diazo compounds and involves the trapping of in situ formed intermediates. Mechanistic investigations indicate that the copper‐catalyzed tandem annulations proceed by allenoate formation and subsequent intramolecular hydroamination. In contrast, the rhodium‐catalyzed protocol features a carbenoid insertion into the N? H bond and subsequent Conia‐ene cyclization. 相似文献
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本文将数据挖掘的新方法支持向量机应用于隧道围岩分级。支持向量机是一种基于统计学习理论的新的学习算法,比神经网络算法能更好地解决小样本问题。选用岩层厚度、岩体结构、嵌合程度、风化程度、地下水特征、节理发育程度、榔头敲击声和地应力等8个定性指标作为评判因子,用泥巴山隧道采集的实际数据作为样本对不同核函数的支持向量机进行训练,并得到评判因子与围岩级别的映射关系,从而可以对未知的围岩样本进行级别判别。判别结果表明: 采用多项式核的支持向量机对围岩级别进行判别有较高的准确率,是一种值得推广和应用的围岩智能分级方法。 相似文献
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