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81.
82.
The Pao-Sah model for the long-channel MOSFET is generalized to include MOSFETs with resistive-gate electrodes (RG-MOSFETs). The RG-MOdSFETs current-voltage characteristics are studied using this extended Pao-Sah model. The steady-state operation of the RG-MOSFET can be divided into three regimes, separated by the uniform channel condition and the pinch-off condition, respectively. The regions of operation are discussed, and a simple analytical I -V expression is given for the device 相似文献
83.
Summary Building blocks containing multi-aryl ethers linkage in larger size for rapid building larger dendrimers were prepared with 3,5-di(4-hydroxyphenoxy)benzyl alcohol (1) as branch monomer and 1,3,5-tri(4-hydroxyphenoxy)benzene (2) as core molecule. Two generation of dendritic polyethers (12 and 15) were obtained by Fréchet convergent approach with 3,5-diphenoxybenzyl bromide (3) as starting molecule. They were characterized firstly by 1H-NMR, 13C-NMR, and MS. 相似文献
84.
实时跟踪控制系统中的数字滤波技术 总被引:2,自引:0,他引:2
在高精度的实时跟踪控制系统中,由探测器等其他一些因素给系统带来的噪声将不容忽视,数字滤波将是滤除噪声的有效手段,,由于系统实时性和采样频率的要求,本文介绍几种时跟踪系统中常用的数字滤波方法,并对它们在实时跟踪系统中的作用进行了和比较。 相似文献
85.
激光对抗技术发展动态 总被引:6,自引:1,他引:5
激光对抗主要包括激光侦察告警、激光无源干扰和有源干扰,以及激光防护几方面。本文概述了激光对抗技术的发展。 相似文献
86.
用工控机组成了油田注水站数据采集系统.给出了系统的组成及测量方法,并讨论了系统的可靠性等问题. 相似文献
87.
大型离心复合球墨铸铁轧辊的生产 总被引:1,自引:0,他引:1
简述了我公司为舞阳铜厂试制4200mm厚板轧机离心复合球墨铸铁轧辊的性能要求、内外层双重金属铸造工艺参数的选择及整个铸造生产工艺过程。 相似文献
88.
Steven S Fu Miles McFall Andrew J Saxon Jean C Beckham Timothy P Carmody Dewleen G Baker Anne M Joseph 《Nicotine & tobacco research》2007,9(11):1071-1084
We conducted a systematic review of what is known about the relationship between post-traumatic stress disorder (PTSD) and smoking to guide research on underlying mechanisms and to facilitate the development of evidence-based tobacco treatments for this population of smokers. We searched Medline, PsychINFO, and the Cochrane Central Register of Controlled Trials and identified 45 studies for review that presented primary data on PTSD and smoking. Smoking rates were high among clinical samples with PTSD (40%-86%) as well as nonclinical populations with PTSD (34%-61%). Most studies showed a positive relationship between PTSD and smoking and nicotine dependence, with odds ratios ranging between 2.04 and 4.52. Findings also suggest that PTSD, rather than trauma exposure itself, is more influential for increasing risk of smoking. A small but growing literature has examined psychological factors related to smoking initiation and maintenance and the overlapping neurobiology of PTSD and nicotine dependence. Observational studies indicate that smokers with PTSD have lower quit rates than do smokers without PTSD. Yet a few tobacco cessation treatment trials in smokers with PTSD have achieved quit rates comparable with controlled trials of smokers without mental disorders. In conclusion, the evidence points to a causal relationship between PTSD and smoking that may be bidirectional. Specific PTSD symptoms may contribute to smoking and disrupt cessation attempts. Intervention studies that test behavioral and pharmacological interventions designed specifically for use in patients with PTSD are needed to reduce morbidity and mortality in this population. 相似文献
89.
Xia Haihong Zhao Zhixiang Li Jigen Shi Yongqian Han Yinlu Zhu Shengyun Xu Yongli Guan Xialing Cui Baoqun Fu Shinian 《Frontiers of Energy and Power Engineering in China》2007,1(2):135-140
The conceptual study on the accelerator driven system (ADS) that lasted for about five years ended in 1999 in China. As one
project of the National Basic Research Program of China (973 Program) in the energy domain, which is sponsored by the China
Ministry of Science and Technology (MOST), a five-year-program of fundamental research of ADS physics and related technology
was launched in 2000 and passed national review at the end of 2005. The China Institute of Atomic Energy (CIAE), the Institute
of High Energy Physics (IHEP), the Institute of Heavy Ion Physics in Peking University (PKU-IHIP) and other institutions jointly
carried out the research. The research activities were focused on HPPA physics and technology, reactor physics of external
source driven sub-critical assembly, nuclear data base and material study. For HPPA, a high current injector consisting of
an ECR ion source, LEBT and an RFQ accelerating structure of 3.5 MeV was built. In reactor physics study, a series of neutron
multiplication experimental study has been carried out and still being done. The VENUS facility has been constructed as the
basic experimental platform for neutronics study in ADS blanket. It’s a zero power sub-critical neutron multiplying assembly
driven by external neutron produced by a pulsed neutron generator. The theoretical, experimental and simulation study on nuclear
data, material properties and nuclear fuel circulation related to ADS is carrying on to provide the database for ADS system
analysis. The main results on ADS related researches will be reported. 相似文献
90.
介绍了以磷酸为粘结剂的高铝钒土砂的组成和性能及在离心铸造端盖造型上的使用方法和使用效果。实践证明,它具有很好的经济效益和社会效益。 相似文献