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1.
通过开展低杂波电流驱动效率与等离子体参数相关性研究,HT 7装置上的最大电流驱动效率达到ηCD=neRpIRF/PLH≈1.4×1019A·W-1·m-2。实验结果表明,优化低杂波的功率谱、等离子体密度、纵场等参数对提高驱动效率起到了关键作用。驱动效率对波谱、密度有较强的依赖性,波谱在Npeak‖=(2.45~2.9),密度为(1.5~2.0)×1013cm-3时驱动效率较高;驱动效率随着纵场的升高而增大;同时,改善托卡马克壁状态、降低杂质水平、提高放电稳定性,对提高驱动效率有积极作用。  相似文献   

2.
为提高 HL-2A 装置低杂波电流驱动系统的实验效率,研制了高反射保护系统。使用 Verilog 硬件描 述语言设计数字信号处理电路,选择 EPM240T100C4 型可编程逻辑器件(CPLD)实现数字信号处理;使用一个 14 位计数器,实现了在低杂波系统反射保护动作后间隔 3.6ms 后重启的功能。测试结果表明,该保护系统实现了设 计要求。  相似文献   

3.
第1期反向场位形下的引导中心哈密顿函数·······~~·······~··,.···“····~····~···············”、“”·”····“…沐建林蔡诗东(1)H卜1装置放电坪区小破裂现象分析·~···~·····~··~··“·~············““···········~····~·”··.”···一··~·~“一严龙文 石秉仁郑永真彭利林黄克强(9)HL一l装置低杂波电流驱动波导阵列优化设计“·”····”·””·”·~········,···~·“,····”··”·“···一焦一鸣石乘仁(1…  相似文献   

4.
第1 期安息香及其衍生物光反应的0**P研究……………·耳太嫂 严宝珍 李二成 徐广智(1)卜茶黄酮和卜二氢秦黄酮类化合物的’‘C—NMR研究 、·、……………,…………·。·。……··、…、…、壬 动 高从元 吕以仙 蔡孟深(11)*OE和二维*M R技术在倍半帖化学位移归属中的应用………桑 鸿 汪汉卿 涂永强(19)某些酸性磷(膀)酸酯 Vq 11)配合物的四氢吠哺中的氧化过程的 ESR研究 ‘·、…·、··、·‘…··低德余 黄杠波 冯亚菲 程朝荣 徐元植门9)乙基紫苏霉素硫酸盐的选择性远程***T和二维*MR研究 .、…..、………、………。………·…  相似文献   

5.
在EAST上通过分析剩余环电压与低杂波功率之间的关系,计算得到了低杂波电流驱动效率。采用归一化功率,即功率对等离子体电流、电子密度、等离子体大半径以及有效电荷数归一化,将所有数据绘制在同一曲线中,这样可以得到不同等离子体参数下的低杂波电流驱动效率。实验得到低杂波电流驱动效率η0=(0.5~1.3)×1019 A.m-2.W-1,在等离子体电流Ip=277kA、低杂波功率PLH=681kW条件下,实验得到长达3s的低杂波全波驱动。  相似文献   

6.
利用射线追踪和福克-普朗克方程,研究了CFETR上驱动电流和功率沉积对低杂波注入位置和耦合波谱的依赖关系,讨论了边界非线性效应对电流驱动与功率沉积的影响,给出了低杂波平行折射率和低杂波注入位置的一个优化值。初步数值计算表明:边界非线性效应会导致驱动电流降低;不考虑低杂波非线性效应时,驱动电流的差异约为6%左右,小于考虑该效应时的差异(~25%)。  相似文献   

7.
赵孔胜  轩瑞杰  韩笑  张耕铭 《物理学报》2012,61(19):197201-197201
在室温下制备了基于氧化铟锡(ITO)的底栅结构无结薄膜晶体管. 源漏电极和沟道层都是同样的ITO薄膜材料,没有形成传统的源极结和漏极结, 因而极大的简化了制备流程,降低了工艺成本.使用具有大电容的双电荷层SiO2作为栅介质, 发现当ITO沟道层的厚度降到约20 nm时, 器件的栅极电压可以很好的调控源漏电流. 这些无结薄膜晶体管具有良好的器件性能: 低工作电压(1.5 V), 小亚阈值摆幅(0.13 V/dec)、 高迁移率(21.56 cm2/V·s)和大开关电流比(1.3× 106). 这些器件即使直接在大气环境中放置4个月, 器件性能也没有明显恶化:亚阈值摆幅保持为0.13 V/dec,迁移率略微下降至18.99 cm2/V·s,开关电流比依然大于106.这种工作电压低、工艺简单、 性能稳定的无结低电压薄膜晶体管非常有希望应用于低能耗便携式电子产品以及新型传感器领域.  相似文献   

8.
工艺翅大规模集成电路光学光刻技术的现状与展望 (9 1.1)硬脆材料钻孔加工技术的研究·,··~……(91·l)大口径锗单晶的切片工艺············……(91·l)介绍一种新型的金属箔分划板······……(91·1)光学玻瑞加工后的表面结构研究···……(91·2)全息光栅复制工艺的研究············……(91·2)一种新型光学加工机床的探讨······……(91·3)用投影仪检控边厚差和中心差偏差……(91·3)偏翻酸钡(..0)晶体加工···············……(91.3)光胶垫板主要技术指标的给定及应用二(91·3)固…  相似文献   

9.
Bai白银生:(见白银生:(见Bi毕传兴:(见Bian卞正中:(见卞正中:(见BretagneBREjTAGNEE赵俊渭等:机载声呐声信号的高速双向多路传输研究)················……No郭业才等:水中运动目标动态线谱增强算法研究)····················……No周广林等:矩形测量面扫描测量声强时扫描路径研究)················……N。(52)(326)(447)陈砚圃等:语音中相位的听觉感知实验研究)····……周秦武等:基于小波的超声斑纹噪声抑制与对比度增强)No·1(7)No4(381)el:(见金滔等:行波型热声驱动器…  相似文献   

10.
用二阶微扰理论结合6-311+G**、6-311++G**和6-311++G(2d,2p)基组对氢键相互作用二聚体HNO···HArF进行研究.在MP2/6-311+G**、MP2/6-311++G**和MP2/6-311++G(2d,2p)水平上,利用标准方法和均衡校正方法对二聚体进行了几何优化、振动频率和相互作用能的计算.对于相互作用能采用G2MP2方法计算.计算结果表明存在两种稳定的二聚体HNO···HArF结构,在这两种结构中,Dimer I(H···F)比Dimer II(H···O)更加稳定.通过振动频率的计算表明,在Dimer I(H···F)中存在N-H···F蓝移氢键,在DimerII(H···O)中存在Ar-H···O红移氢键,并对蓝移氢键加以确认.利用电子密度拓扑学分析和自然键轨道分析对于氢键红移和蓝移进行了合理解释.  相似文献   

11.
Two-dimensional scanning of a 0.6328 mum guided-light beam has been realized using noncolinear acousto-optic (AO) coplanar Bragg diffraction together with colinear AO guided-mode to substrate radiation-mode conversion in a Z-cut Xpropagation LiNbO3 proton-exchanged (PE) waveguide. The two surface acoustic (SAW) waves utilized are at the center frequencies of 500 and 200 MHz, propagating in the Y and X axes, respectively. Two-dimensional scanning of approximately 720 resolvable light beam spots, namely, 18 40 (horizontal vertical) scanning, has been demonstrated using a light beam of 1.0 mm aperture. The total number of resolvable beam spots can be greatly increased from 720 by simply utilizing SAW transducers of larger bandwidth and a light beam of greater aperture. It should also be possible to significantly increase the diffraction efficiency from 3 % by optimizing the parameters of the PE waveguide and the SAWs.  相似文献   

12.
A review of schemes for multiple access in fiber optic networks shows that a hybrid of wavelength and code division multiple access (WCDMA) combines the best features of both. In particular, the hybrid scheme retains the large information carrying capacity of wavelength division multiple access (WDMA) and flexibility of code division multiple access (CDMA). In this paper WDMA, optical CDMA (OCDMA), and WCDMA networks are discussed. In OCDMA networks, concept of incoherent and coherent coding including inverse decoding and matched filter is introduced. The delay performance of both WDMA and WCDMA networks, under the simple suboptimum access protocols based on cyclic search, is computed. It has been shown quantitatively that tuning delay significantly affects the delay performance of both WDMA and WCDMA networks. Futhermore, delay performance of WCDMA networks is always better than the WDMA networks for the same tuning delay, load, and number of users.  相似文献   

13.
Results of a study of the effect of γ-radiation on the spectral luminescence properties of cadmium tungstate crystals doped with silver, bismuth, and molybdenum cations are presented. Spectral characteristics of the nondnnnoped crystals are briefly described. Absorption and photo and X-ray luminescence spectra of the crystals taken before and after exposure to γ-radiation (5.5·104 Gy) are compared. It is found that the spectral characteristics of the crystals doped with silver, bismuth, and molybdenum cations do not change markedly after the exposure. The relation between the type of impurity-induced defects, individual characteristics of the impurity cations, and the character of the effect of γ-radiation on the spectral luminescence properties of impure crystals is analyzed (preliminarily). Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 55–60, January–February, 1997.  相似文献   

14.
A simple technique of pulse compression, based on the linear chirp compensation of self-phase modulation (SPM) spectra in dispersion shifted fibers, is demonstrated. The optimization procedure is carried out, for a short span of a single-mode fiber, using a parabolic law, which describes the behavior of the squared output pulse width versus the pump peak power in the case of Gaussian pulses. The experimental results give a minimum pulse duration of 233 fs, which is in good agreement with the model. Shorter and coherent pulses, down to 90 fs, have been obtained by inserting an interference filter at the optical output.  相似文献   

15.
The Shanghai Synchrotron Radiation Facility(SSRF)booster ring,a full energy injector for the storage ring,is deigned to accelerate the electron beam energy from 150MeV to 3.5GeV that demands high extraction efficiency at the extraction energy with low beam loss rate when electrons are ramping.Closed orbit distortion(COD)caused by bending magnet field uniformity errors which affects the machine performance harmfully could be effectively reduced by bending magnet location sorting.Considering the affections of random errors in measurement,both ideal sorting and realistic sorting are studied based on measured bending magnet field uniformity errors and one reasonable combination of bending magnets which can reduce the horizontal COD by a factor of 5is given as the final installation sequence of the booster bending magnets in this paper.  相似文献   

16.
17.
We measure the waveform and phase curves of short optical pulses before and after transmission over different lengths of fibers by use of the pulse analyzer with the frequency-resolved optical gating (FROG),and numerically simulate pulse evolution under the experimental conditions.The nonlinear coefficient of the fiber is given by comparing the experimental results with the numerical ones.Difference between the experiment and numerical simulation is analyzed.  相似文献   

18.
Resonance scattering of elastic spherical shell and cylindrical shell while the surrounding fluid medium has absorption is studied. The normal mode solution derived using exact elastic theory and the separation of variables is still applicable. However, the scattering form function has to be modified for the absorbing medium, otherwise the unreasonable result would be obtained. The backscattering form function in the absorbing medium is redefined, and the form function of elastic spherical and cylindrical shell with vacuum or solid matter filled is calculated in various absorption conditions. The results show that the absorption of surrounding fluid leads to notable attenuation of the coincidence resonances in the mid-frequency, but it has a little influence on the low-frequency resonance scattering induced by the filler inside the shell.  相似文献   

19.
A versatile and low-cost single-beam self-referenced phase-sensitive surface plasmon resonance(SPR)sensing system with ultra-high resolution performance is presented.The system exhibits a root-mean-square phase fluctuation of ±0.0028.over a period of 45 min.i.e.a resolution of±5.2×10-9 refractive index units.The enhanced performance has been achieved through the incorporation of three design elements:a true single-beam configuration enabling complete self-referencing so that only the phase change associated with SPR gets detected,a differential measurement scheme to eliminate spurious signals not related to the sensor response,and the elimination of retardation drifts by incorporating temperature stabilization in the liquid crystal phase modulato .Our design should bring the detection sensitivity of non-labeling SPR biosensing closer to that achievable by conventional fluorescence-based techniques.  相似文献   

20.
Ta2O5 films are prepared on BK7 substrates with conventional electron beam evaporation deposition.The effects of SiO2 protective layers and annealing on the laser-induced damage threshold (LIDT) of the films are investigated.The results show that SiO2 protective layers exert little influence on the electric field intensity(EFI)distribution,microstructure and microdefect density but increase the absorption slightly.Annealing iS effective on decreasing the microdefect density and the absorption of the films.Both SiO2 protective layers and annealing are beneficial to the damage resistance of the films and the latter is more effective to improve the LIDT.Moreover,the maximal LIDT of Ta2O5 films is achieved by the combination of SiO2 protective layers and annealing.  相似文献   

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