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111.
梳理任务可用度的基本模型,构建装置执行任务的过程类型和时间模型图,体现任务时限和修复时限的要求,以此给出装置单次任务可用性评价模型 ;选用曲线拟合和拟合优度检验方法,考虑修复对任务影响程度差异及其发生概率,建立装置多次任务可用性评价模型、评价方法及分析步骤,为系统地开展惯性约束聚变激光装置可用性评价提供一般模型和方法。通过对神光-Ⅲ原型装置使用可靠性数据处理和分析,验证提出的模型和分析方法的正确性和经济性。研究成果将直接应用于神光-Ⅲ主机装置的可靠性工程建设中。 相似文献
112.
Yuanting Su Xingyong Wang Xin Zheng Zaichao Zhang You Song Yunxia Sui Yizhi Li Xinping Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(11):2901-2905
Three bis(triarylamine) dications were isolated by using weakly coordinating anions. Their electronic structures in the ground state were investigated by various experiments in conjunction with theoretical calculations. The ground‐state electronic structures of these species were tunable by substituent effects, with two of them as closed‐shell singlets and one of them as an open‐shell singlet in the solid state. The excited state of the latter is thermally accessible, indicated by EPR and SQUID measurements. The work provides a new and stable diradicaloid structure motif with an excited triplet sate. 相似文献
113.
Ju‐You Lu Hong Wan Jianwei Zhang Zhixuan Wang Yang Li Yongmei Du Chunying Li Prof. Zhao‐Tie Liu Prof. Zhong‐Wen Liu Prof. Jian Lu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(49):17542-17546
A palladium‐catalyzed direct C‐arylation reaction of readily available cage carboranyllithium reagents with aryl halides has been developed for the first time. This method is applicable to a wide range of aryl halide substrates including aryl iodides, aryl bromides, and heteroaromatic halides. 相似文献
114.
Soo Ouk Jang Hyun Jong You Young-Woo Kim Yong Ho Jung In Uk Hwang Jae Yang Park Heon Lee 《Plasma Chemistry and Plasma Processing》2014,34(1):229-237
To deposit copper seed layer on ultra large scale integration devices, a large-area (Ø 378 mm) electron cyclotron resonance plasma has been generated by using permanent magnets-embedded Lisitano antenna. The plasma source operates in the pressure range of 0.2–1.5 mTorr with microwave power range of 500–2,000 W. By using a Langmuir probe, the electron density and temperature have been measured near the DC sputter target position. Measurements indicate argon plasmas having electron densities of ~5 × 1010/cm and electron temperatures of 5 eV with 750 W microwave power at gas pressures of 0.5 mTorr. Using this plasma source and a DC sputter, we obtained excellent conformal copper seed layer with high aspect ratios of 12:1. This is in contrast with conventional methods using magnetron sputter, which has aspect ratios of 2–3:1. Also, improvements are observed in the smoothness (root mean square roughness of 1.345 nm), uniformity (2.5 % at 300 mm wafer), and sidewall symmetricity (more than 95 %) of the copper seed layer. 相似文献
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A novel cellulose-based polyampholyte derivative, carboxylethyl quaternized cellulose (CEQC), was homogeneously synthesized by introducing positively charged quaternary ammonium groups and negatively charged carboxyl groups to the backbone of cellulose. The structure and dilute solution properties of CEQCs were characterized with elemental analysis, FTIR, NMR, viscometer, light scattering and zeta-potential measurement. The nitrogen content and total degree of substituent of acylamino and carboxyl groups increased with an increase of the molar ratio of acrylamide to the anhydroglucose unit of quaternized cellulose (QC). The salt-resistance of CEQC was improved remarkably by introducing opposite charged carboxyl to the QC chains. The intrinsic viscosity of the prepared polyampholytes was found to be very sensitive to the pH of the solutions. CEQC-1, the sample with relative low content of carboxyl groups, behaved as a classical cationic polyelectrolyte. However, CEQC-2 and CEQC-3, the samples with higher content of carboxyl groups, displayed typical polyampholyte behavior, and the isoelectric points (IEP) were determined to be 5.0 and 3.8 respectively. This work provided a facile method for the synthesis of novel cellulose-based polyampholytes with different IEP. 相似文献
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Structural Chemistry - Three new versatile azido-bridged Schiff base Copper(II) complexes, [Cu2(L1)2(μ1,1-N3)2]·2CH3OH (1), [Cu(L2)(μ1,3-N3)] n (2), and [Cu2(L3)(μ1,1-N3)2(N3)]2... 相似文献
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