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41.
Ion-ripple laser, which consists of a relativistic electron beam obliquely propagating through an ion-ripple in a plasma, is investigated by nonlinear numerical simulation. The influence of the component of the ion-ripple field parallel to the beam direction on beam-wave interaction is analyzed. The results show that the longitudinal component of the ion-ripple field has a considerable influence on ion-ripple laser. The operating parameters are also optimized.  相似文献   
42.
一种基于三次样条函数求离子浓度的自动算法   总被引:1,自引:0,他引:1  
本文提出了一种用三次样条函数模拟双次标准加入法测量方程,直接求解离子浓度的自动算法。比较了三咱不同边界条件下用要池数计算离子浓度的结果。造出节点区间两极端点的二阶导数为零时的三次样条函数为最佳模拟函数。并讨论了该方法在实际分析中误差的来源及消除办法。经对一系列文献数据的验算对比,表明本法完全可代替传统的迭代法和查图法,且能方便地设置在智能化的电位分析系统中。  相似文献   
43.
脉冲序列的快速搜索法及可信度分析   总被引:6,自引:0,他引:6  
对于周期脉冲序列的信号分选识别,可采用序列搜索的时域方法[1,2]。本文将大周期内完全重复的脉冲序列分解为多个“单周期信号”.并把它们均定义为周期性信号.同时,提出了序列搜索的一种软件实现方法及密集视频脉冲信号分选的变步长、信步长快速搜索法.在此基础上,本文针对序列搜索分选法的可信度计算公式进行了推导和分析,证实了这种方法的可行性和有效性.  相似文献   
44.
In the present paper, the reversible effects between energy-absorbing and energy-reflecting states of chameleon-type building coatings were studied through demonstration of the layers’ properties using infrared thermal imaging of the layers when exposed to a sunlamp or temperature measurements of the layers during exposure to sunlight at different ambient temperatures. The reversible transforming mechanism between the energy-absorbing and energy-reflecting states of the chameleon-type building coatings was investigated with IR, Raman and 1H NMR spectroscopy. The infrared thermal image results showed that when reversibly thermochromic pigments were added to normal white building coatings, the chameleon-type building coatings could absorb energy from the sunlamp below a switching temperature of about 18°C. Absorption of energy from the sunlamp stopped automatically above the switching temperature. The results from exposure to solar radiation showed that when the temperature was below the switching temperature, the chameleon-type building coating could absorb almost the same amount of solar energy as an ordinary coloured coating, and when the temperature was above the switching temperature, the chameleon-type building coating could reflect more solar energy than the ordinary coloured coating. The above results showed that chameleon-type building coatings could contribute to a thermally comfortable building environment. The IR spectroscopy results showed that when the environmental temperature was below the switching temperature of 18°C, the lactone ring of the thermochromic pigment molecule would open and the band of C=O would almost disappear. Raman spectra indicated that the band of C–O in would move to the high wave number range. From 1H NMR spectra, it could be found that there was some action between the hydrogen of the hydroxyl and the structure of . During the lactone ring opening, the electron in the non-bond orbital would transit to the higher orbital and it could elongate the conjugated bridge, which would produce visible absorption and hence produce an energy-absorbing effect. However, when the environmental temperature was above the switching temperature of 18°C, the lactone ring in the molecule of the thermochromic pigment would close, the transited electron would transit back to the original orbital, hence the visible absorption would disappear, which would make the coating have an energy-reflecting effect.  相似文献   
45.
人工神经网络及模糊控制在陶瓷窑炉自控系统中得到日益广泛的应用,它们自身的发展也不断推动陶瓷窑炉智能控制的开发及应用,但是在陶瓷窑炉自控智能化的进程中仍存在一些问题有待于解决。  相似文献   
46.
介绍了古洞口工程泄洪洞工作弧门在特定地形下采用固定卷扬式启闭机和汽车吊配合闸室的预埋件进行闸门安装的施工工艺。对闸门的吊装、调整及焊接工艺的具体措施作了详细分析,解决了该工作弧门在洞内安装的关键施工技术问题。  相似文献   
47.
In this paper, any two of the three anticorrosion agents, that is emulsifier (OP-10), soluble glass (Na2O·nSiO2) and glycerin (C3H8O3), were treated simultaneously on the surface of amorphous (a-) MgNi+5% Ml2Mg17 (Ml denotes the lanthanum-rich mish metal) electrode and the electrolyte. Effect of the synergistic anticorrosion treatment on charging/discharging cycle stability of the electrode was investigated. Contrasted with single treatment method, the cycling stability of the electrodes was further improved. The desirable synergistic anticorrosion method was that the electrode was treated by the soluble glass, and that OP-10 was added into the electrolyte. The cyclic voltammogram (CV) results of the electrode show clearly that the anticorrosion agent can change the electrochemical activity and mechanism of the electrode. The concentration of the anticorrosion agent in the electrolyte treated by the synergistic anticorrosion method was also investigated. The appropriate concentration of the anticorrosion agents in the electrolyte is 0.143%.  相似文献   
48.
In this paper, a new polysilicon CMOS self-aligned double-gate thin-film transistor (SA-DG TFT) technology is proposed and experimentally demonstrated. The self-alignment between the top- and bottom-gate is realized by a backlight exposure technique. The structure has an ultrathin channel region (300 /spl Aring/) and a thick source/drain region. Experimental results show that this technology provides excellent current saturation due to a combination of the effective reduction in the drain field and the full depletion of the ultrathin channel. Moreover, for n-channel devices, the SA-DG TFT has a 4.2 times higher on-current (V/sub gs/=20V) as compared to the conventional single-gate TFT. Whereas for the p-channel devices, the SADG TFT has a 3.6 times higher on-current (V/sub gs/=-20V) compared to the conventional single-gate device.  相似文献   
49.
众所周如,西藏地区是研究地球深部结构和构造的窗口,是研究大陆板块学说的重要场所,也是寻找热源和其它矿产资源的有利地区.因此,世界各国地学科学家都希望在本地区进行科学研究工作,或与我国科学工作者协作共同探索这一重要地区.中国和法国的地质、地球物理科学家经商讨共同组成“中法喜马拉雅山地质研究队”,对西藏中部广大地区进行地质、地球物理的科学研究工作.深部地震探测是地球物理研究中的重要内容.中法双方共同决定,在中国西藏南部的日喀则地区至北边的那曲地区作地震探测工作.为了探测地壳上地幔的结构,1981年在西藏的南部佩枯错至普莫雍错500公里的喜马拉雅山北麓——雅鲁藏布江地区进行了人工爆炸地震探测工作.本文是中法地质研究队合作的深部地震探测资料的解释结果.  相似文献   
50.
三峡水电站ALSTOM机组低水头运行稳定性分析   总被引:2,自引:1,他引:1  
混流式水轮机的水力稳定性与机组水力工况密切相关。以三峡电站左岸6号机组稳定性试验为例,分析了ALSTOM机组的低水头运行稳定性。根据试验分析结果,可将机组运行工况划分为小负荷区、涡带振动区、大负荷运行区。小负荷区机组效率较低,机组不宜在此区间运行;大负荷区机组运行稳定性最佳,但机组应避开强涡带工况区和特殊频率振动区运行。  相似文献   
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