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991.
992.
Experimental Investigation on Low Magnetic Field Operation of an Overmoded Slow-Wave High-Power Microwave Generator 下载免费PDF全文
The experimental results of an overmoded slow-wave high-power microwave generator operated at low magnetic field are presented. The feasibility of low magnetic field operation is investigated both theoretically and experimentally based on the characteristics of the overmoded slow-wave device. The experiments were carried out at the Spark-2 accelerator. Under the condition of guiding magnetic field strength of 0.55 T, diode voltage of 4 74 k V,and beam current of 5.2kA, a microwave was generated with power of 510 MW, mode of TM01, and frequency of 9.54 GHz. The relative half-width of the frequency spectrum is less than 1%, and the beam-to-microwave efficiency is about 21% in our experiments. 相似文献
993.
Low-lying and high-spin states of ^124 Cs are studied through the ^116 Sn(^11 B,3n)^124 Cs reaction at a beam energy of 45 MeV. Several new linking transitions are observed, including three transitions between the yrast and πh11/2 vd3/2 bands and two transitions between the yrast and πh11/2 v(d5/2, g7/2) bands. These transitions fix the excitation energy of the yrast band and its decay path, and confirm the existence of eight E1 finking transitions between the yrast and πh11/2 v(d5/2, 97/2) bands observed before. These E1 linking transitions infer the oetupole correlation in ^124Cs. The decay paths of the yrast band are investigated, and discrepancies in the level scheme of ^124Cs in the latest two studies are clarified. The reason for the discrepancies is discussed. A new decoupled band is established and temporarily assigned as the unfavored signature partner of πh11/2 vd3/2 configuration. 相似文献
994.
995.
CdS microspheres were prepared by a hydrothermal microemulsion method in cyclohexane/Triton X-100/pentanol/water at 180℃. The as-prepared samples were characterized by X-ray diffraction analysis, transmission electron microscopy, electron diffraction, energy diffraction X-ray analysis and photoluminescence spectra. It was found that CdS microspheres with diameter of 1.5-2.5μm were aggregated by nanocrystals. The formation mechanism was proposed. 相似文献
996.
由碳酸钠诱导形成的油酸钠蠕虫状胶束的流变学性质 总被引:3,自引:0,他引:3
当Na2CO3浓度逐渐增加时, 用流变学的方法研究了阴离子表面活性剂油酸钠(NaOA)在溶液中从胶束转变成蠕虫状胶束的过程. 首先测量体系剪切粘度(η)和剪切速率的关系得到零剪切粘度(η0). 然后由动态振荡实验得到复合粘度(|η*|)、动态模量(储能模量G'、损耗模量G"和结构松弛时间τs)等物理量. 应用Cox-Merz规则和Cole-Cole图, 证明NaOA (0.040~0.080 mol/L)/Na2CO3 (0.25~0.50 mol/L)体系形成蠕虫状胶束, 且蠕虫状胶束的动态粘弹性在NaOA (0.050~0.080 mol/L)/Na2CO3 (0.35~0.45 mol/L)范围是符合Maxwell模型的线性粘弹性流体. 相似文献
997.
摘要对B^ 注入的n-on-p平面结和分子束外延(MBE)技术原位铟掺杂的n-on-p台面异质结的碲镉汞(HgCdTe)长波光伏探测器暗电流进行了对比分析.与n-on-p平面结器件相比,原位掺杂的n-on-p台面异质结器件得到较高的零偏动态阻抗一面积值(RoA).通过与实验数据拟合,从理论上计算了这两种结构的器件在不同温度下的RoA和在不同偏压下的暗电流,得到一些相关的材料和器件性能参数. 相似文献
998.
BaWO4纳米线束的合成及其光学性质研究 总被引:1,自引:0,他引:1
High quality BaWO4 nanowire bundles have been synthesized in toluene-sodium dodecylbenzene sulphonate (SDBS)-small amount PEG20000-H2O reverse micelle system. XRD result shows that the obtained BaWO4 belongs to tetragonal phase with scheelite structure. TEM results demonstrate that the obtained BaWO4 nanowire bundles have high aspect-ratio (>650). The experimental results confirm that PEG20000 plays a key role for the formation of BaWO4 nanowire bundles. Other factors which influence the morphology and crystallinity of the product are also briefly discussed. Moreover, the obtained BaWO4 nanowire bundles exhibit strong photoluminescence centered at 397.3 nm with λex=343.5 nm at room temperature, which is different from the bulk BaWO4 crystals. 相似文献
999.
1000.