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反转永磁聚焦C波段高功率多注速调管作为加速器系统的功率源,具有脉冲输出功率高、平均功率大、寿命长的优势,在工业辐照、放射治疗、无损检测等领域具有广阔的应用前景。设计并研发了一种可用于加速器系统的反转永磁聚焦C波段高功率多注速调管。其电子光学系统采用多电子注、周期反转永磁聚焦技术,高频系统工作在TM220高次模式、多腔参差调谐,散热采用水冷方式。通过计算确定了结构参数,研制出速调管样管,通过测试,获得了大于3 MW的峰值输出功率,和计算结果相吻合。 相似文献
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The thermal reaction of chiral 2-phenyl-4-(p-X-phenyl)-5-(p-Y-phenyl)-4-tert-butyldimethylsilylperoxy-4H-isoimidazoles (5b: X = CF3, Y = OMe; 5c: X = CF3, Y = F) was carried out in DMSO. The chiral 2-phenyl-5-(p-X-phenyl)-5-(p-Y-phenyl)-5H-imidazol-4-ones (4b: X = CF3, Y = OMe; 4c: X = CF3, Y = F) were quantitatively obtained in 50-60% enantiomer excess (ee). The mechanism for the reaction was proved to be stereoselective 1,5-phenyl migration. Although the sigmatropic 1,5-phenyl migration should be thermally allowed according to the Woodward-Hoffmann rule, the migration actually includes a stepwise process. 相似文献
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Yi Fan Zhizhi Sheng Jun Chen Hong Pan Baiyi Chen Feng Wu Shuli Wang Xinyu Chen Xu Hou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(12):4007-4011
Chemical detection has a wide range of applications. The detection of a certain substance is so vital that new detection mechanisms with features such as low‐cost, accessibility, and readily available visual markers are in demand. Herein, a liquid‐gating‐based chemical‐detection mechanism is reported, which has a dynamic gas/liquid interface due to dipole‐induced interfacial molecular reconfiguration. The mechanism exhibits a sensitive relationship between the dipole‐force‐induced rearrangement of interfacial molecules and transmembrane gating behavior. These features can be utilized to create visual markers for detection by converting the analyte‐mediated interfacial interaction to a pressure‐driven marker movement. This “green” detection mechanism requires no electrical energy input and has readily available markers for anyone to observe directly. This new mechanism opens a window for a more in‐depth exploration of combining liquid‐gating mechanisms with detection mechanisms. 相似文献
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The synthesis of unsymmetrical biaryls with a methylthio group is achieved using the air‐stable palladium–phosphinous acid complexes, [(t‐Bu)2P(OH)]2 PdCl2 (POPd), as the catalyst. A great variety of substituted bromobenzenes having electron‐withdrawing and electron‐donating functional groups in para and meta positions have been successfully coupled with 3‐methylthiophenylboronic acid. 相似文献
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Let (Σ,ρ) be a one-sided symbolic space (with two symbols), and let σ be the shift on Σ. In this paper, we prove that there exists a minimal set T⊂Σ such that σT| is Wiggins chaotic, Martelli chaotic, distributionally chaotic, strictly ergodic, topologically weakly mixing and has zero topological entropy. 相似文献
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ABSTRACTThe thermal compression behaviour of Al–Zn–Mg alloy was studied on a thermal simulator machine at the temperature range of 380–540°C and strain rate range of 0.01–10?s?1. The constitutive equation and 3D processing map of the alloys were established. The microstructure characteristics of the alloy were studied by metallographic observation, electron back-scatter diffraction (EBSD) analysis and transmission electron microscopy (TEM) microstructure analysis. The results show that the peak stress of high-temperature deformation of alloy decreases with the increase of deformation temperature and increases with the increase of strain rate. The dynamic recovery of the alloy occurs at the temperature range of 380–460°C and the strain rate range of 0.01–0.1?s?1. The dynamic recrystallization of the alloy occurs at the temperature range of 460–500°C and the strain rate range of 0.01–0.1?s?1. The alloy maintains fine and uniform recrystallized grains at a temperature range of 460–480°C and a strain rate range of 0.01–0.1?s?1, which is suitable for hot working. 相似文献
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Weiss proved that Devaney chaos does not imply topological chaos and
Oprocha pointed out that Devaney chaos does not imply distributional chaos. In
this paper, by constructing a simple example which is Devaney chaotic but neither
distributively nor topologically chaotic, we give a unified proof for the results of Weiss
and Oprocha. 相似文献
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Zhu J Li W Su Z Chu B Han L Yang D Bi D Li B Hu Z Zhang Z Tsuboi T 《Optics letters》2007,32(24):3537-3539
We demonstrate a nondoped white organic light-emitting diode in which the blue, green, and red emissions are generated from 4,4(')-bis(2,2(')-diphenylvinyl)-1,1(')-biphenyl, tris(8-hydroxyquinoline)aluminum, and a submonolayer of 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7- tetramethyl-julolidyl 9-enyl)-4H-pyran layers, respectively. A thin layer of N,N(')-diphenyl-N,N(')-bis(1-naphthyl)(1,1(')-benzidine)-4,4(')-diamine (NPB), which differed from the traditional hole-transporting layer, was introduced into the device. The thickness of this thin NPB layer was changed to tune the chromaticity and optimize the white color quality. The white device with a 3 nm chromaticity-tuning NPB layer gives the Commission Internationale de l'Eclairage-1931 xy coordinate of (0.327, 0.336), a color rendering index of 90.2, a maximum luminance of 19,096 cd/m(2), and a maximum current efficiency of 4.12 cd/A. The electroluminescence mechanism of the white device was also discussed. 相似文献