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通过对以电容器替代爆磁压缩发生器的系统等效电路进行理论分析,对影响这种调制电路性能的关键问题及其解决方法进行了讨论。根据理论分析结果对调制电路进行了设计。在初步实验中,当用于去除电爆炸丝上附加电压的撬断开关保持断开时,变压器原边电流切断不彻底,电容负载上充电电压峰值为-264 kV;保持其他电路参数不变,而使撬断开关在电爆炸断路开关断开过程中闭合时,变压器原边电流切断彻底,在相同负载上充电电压峰值为-374 kV。实验结果验证了理论分析结果,并证明了采用这种调制电路能够实现爆磁压缩发生器与高阻抗负载匹配。 相似文献
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在“阳”加速器(电流峰值为500—850 kA,上升时间约为85 ns)上利用单壳层喷气负载开展了Z箍缩等离子体内爆实验,获得了等离子体的辐射产额、X光辐射图像等诊断结果.利用相应的诊断结果,定义了内爆时间,对内爆过程的主要阶段进行了划分,研究了等离子体位形、辐射强度分布等实验现象,同时对等离子体的内爆轨迹、内爆质量、径向收缩比、磁流体不稳定性等进行了初步分析.
关键词:
Z箍缩')" href="#">喷气负载Z箍缩
等离子体内爆
X光辐射功率
“阳”加速器 相似文献
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为方便描述聚龙一号装置与Z箍缩负载的电磁耦合过程,基于大量电参数实验数据和全电路模拟分析,建立了一个简化的集总电路模型,获得了等效电压波形和等效电阻、电感等集总参量。采用水介质三板输出线出口位置的开路电压作为等效电压,进一步拟合为正弦平方函数,峰值为3.3 MV(当前驱动器充压为65 kV),零到峰值的时间长度为102.5ns。采用简化的流阻抗模型描述磁绝缘传输线内部空间电子流的电流损失效应。将电路程序与零维负载动力学程序耦合模拟,得到了与实验结果符合的负载电流波形,尤其电流波形的前沿和峰值符合较好,分析了电磁能转化为负载动能的过程。 相似文献
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研制了一种用于磁绝缘传输线(MITL)实验的分压器型大功率水电阻负载,其阻值可在2.0~14.0 变化。利用MATLAB系统辨识工具箱和ANSYS电磁分析模块,分别获取了分压器的系统传递函数和沿面电场分布,给出了其幅频响应特性和沿面闪络可靠性分析,负载设计充分考虑了集肤效应和温升的影响。该负载已用于强光一号1.0 m长MITL特性研究实验,并获得了较好的测量波形,在负载阻值2.1 条件下,负载峰值电压为1.2 MV,峰值电流为494.4 kA,峰值时间约125 ns。将实验测量结果同TLCODE计算结果进行了对比,获得了较为一致的对比结果。 相似文献
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S. Iwama N. Satomi M. Yamanaka S. Goto T. Ishimura H. Ito 《International Journal of Infrared and Millimeter Waves》1981,2(6):1199-1208
A high-power CW 27.972 m water vapor laser has been constructed in order to use as a light source of an interferometer for plasma diagnostics. The laser consists of 220 cm length and 2.0 cm small bore Pyrex glass discharge tube, semi-confocal resonator and Michelson coupler. From the measurement of cavity detuning curves, it is found that two waveguide modes, EH11 and EH21 oscillate. The increase of the output power is found to become more than seven times larger by adding He(50%)–H2(50%) mixed gas. Under the optimum condition, the maximum output power of 65 mW or the output power per unit cavity volume of 83 W/cm3 is obtained. 相似文献
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Gregory Berkolaiko 《Communications in Mathematical Physics》2008,278(3):803-819
We study the number of nodal domains (maximal connected regions on which a function has constant sign) of the eigenfunctions of Schrödinger operators on graphs. Under a certain genericity condition, we show that the number of nodal domains of the n th eigenfunction is bounded below by n ? ?, where ? is the number of links that distinguish the graph from a tree.Our results apply to operators on both discrete (combinatorial) and metric (quantum) graphs. They complement already known analogues of a result by Courant who proved the upper bound n for the number of nodal domains.To illustrate that the genericity condition is essential we show that if it is dropped, the nodal count can fall arbitrarily far below the number of the corresponding eigenfunction.In the Appendix we review the proof of the case ? = 0 on metric trees which has been obtained by other authors. 相似文献
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Gain coefficients have been calculated for transitions of singlet levels ns–np of orbital n=4 and n=5 in magnesium-like ions with atomic numbers Z=18, 19, 20, 21, 22 and 23. Population inversions for 4p and 5p levels in these ions were also calculated, via electron collisional excitation, for electron temperature range of 93–231 eV and electron density range of 1016–1017 cm−3. Under these plasma conditions, the maximum gain that occurred for 4s–4p transition was at electron temperature of 231 eV and electron density of 4×1017 cm−3. Scaling of the maximum gain coefficients with atomic number Z and the plasma parameters is also presented. 相似文献
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M.O. Ramírez D. Jaque J.A. Sanz García L.E. Bausá J.E. Muñoz Santiuste 《Applied physics. B, Lasers and optics》2003,77(6-7):621-623
An optimization of the laser action performance from a diode-pumped Yb3+-doped LiNbO3:MgO crystal has been carried out. In this sense, efficient laser action at 1.06 m when pumping with a fiber-coupled laser diode at 980 nm has been demonstrated, achieving laser slope efficiencies as high as 74%. The influence of output mirror transmittance on both pumping threshold and laser slope efficiency has been investigated, and the parameters of relevance in laser dynamics (emission cross section and optical losses) have been determined. Under the experimental conditions leading to maximum slope efficiency, the pump power at threshold was 300mW, and the pump-to-laser conversion efficiency was 40%. PACS 42.55.Xi; 42.55.Rz; 42.60.Lh 相似文献
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B. Bülow B. Johnsson M. Nilsson B. Forkman 《Zeitschrift für Physik A Hadrons and Nuclei》1976,14(1):89-95
The yields of51V(, xpyn) reactions have been measured at maximum bremsstrahlung energies from 75 to 800 MeV. Mean cross sections have been deduced, compared to Monte-Carlo calculations and analysed with a semiempirical Rudstam formula. Total isobaric mean cross sections and anN/Z dispersion curve in the mass regionA = 42–48 have been obtained. The results are in agreement with cascade-evaporation theory and with earlier data obtained with photons and protons. 相似文献
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I. A. Fomin 《JETP Letters》2016,104(1):20-25
The spatial variation of the orbital part of the order parameter of 3He-A in an aerogel has been represented as random walk of a unit vector l(r) over a sphere under the action of random anisotropy created by the system of strands of the aerogel. The statistical properties of the resulting random texture have been studied. For distances at which the variation of l is much smaller than its magnitude, the average square <δl2> of variation of l has been expressed in terms of the correlation function of the component of the random anisotropy tensor. Under simplifying assumptions on the structure of this correlation function, an analytical dependence of <δl2> on r has been obtained for isotropic and axially anisotropic aerogels. The average values of the squares of the projections of l on the axes of anisotropy for an anisotropic aerogel have been represented in terms of the parameters of the aerogel. The characteristic scale at which the long-range order is broken, as well as the magnitude of global anisotropy sufficient for the recovery of the long-range order, has been numerically estimated within a simple model. The values obtained have been compared to other estimates. 相似文献
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J. Kong D. Y. Tang S. P. Ng L. M. Zhao L. J. Qin X. L. Meng 《Optics & Laser Technology》2005,37(1):7407-54
We report on a high-power diode-end-pumped CW Nd:GdVO4 laser. Under the pump power of 39.5 W, a maximum output power of 19.8 W and a slope efficiency of 58.5% were obtained. The beam quality M2 at maximum output power was measured to be around 2.62. The thermal focal length in Nd:GdVO4 crystal under the pump power from 22 to 40.6 W was measured. The pump-induced damage threshold was estimated to be 28.6 kW/cm2. 相似文献
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研究了Cr3+,Yb3+,Er3+共掺磷酸盐铒玻 璃转镜调Q激光性质.三种Er2O3掺杂浓度的激光实验结果表明,在Er2O3名义掺杂浓 度为0.5wt%时,玻璃的综合激 光性质最好,重复频率为0.1Hz时,它的激光阈值功率为14.5mJ,最大输出能量为9.6mJ ,斜率效率为0.55%.在同种实验条件下,比较了Cr14和Kigre公司生产的QE-7S激光性质参数,实验表明,前者激光阈值功率稍低,而后者的斜率效率和最大输出功率略高.
关键词:
3+-Yb3+-Er3+共掺')" href="#">Cr3+-Yb3+-Er3+共掺
磷酸 盐玻璃
光谱性质
激光性质 相似文献
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J. Brenneisen D. Grathwohl M. Lickert R. Ott H. Röpke J. Schmälzlin P. Siedle B. H. Wildenthal 《Zeitschrift für Physik A Hadrons and Nuclei》1995,352(3):279-291
New assignments of quantum numbers have been obtained for more than 50 levels in28Si between 8953 and 15915 keV excitation energy. They are based on the measurement of -ray angular distributions or anisotropies on 29 resonances of the27Al(p, ) reaction and on the24Mg(a, ) resonance atE
=3355 keV. A total of 15 high-spin states withI=5–7 has been obtained and the spectrum ofT=1 states has been identified up to 15915 keV excitation energy and a maximum spinI=6. 相似文献
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M. Takai Y. F. Lu T. Koizumi S. Namba S. Nagatomo 《Applied Physics A: Materials Science & Processing》1988,46(3):197-205
Single crystal ferrite has been etched by focused Ar+ laser irradiation in a CCl4 gas atmosphere. The etched groove showed cracks due to thermal stresses when samples were etched by a laser vaporization process in a vacuum, while in a CCl4 atmosphere, such cracks were not observed. An etching rate of 68 /s obtained for a thermochemical process by laser irradiation was four orders of magnitude higher than that for a wet chemical etching process. A high aspect (depth-to-width) ratio of up to 10 was obtained for etched grooves. Under specific conditions, bending of the groove and orientation dependence in etching rate were observed. 相似文献