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61.
The essential goal of that paper (Chin. Phys. Lett. 26(2009) 124211) was to obtain a 2μm Tm:YAG laser with short pulse output. A Q-switched technique is used to realize the short pulse output in our laser system. The idea presented by Dr. Nieolaie Pavel is right. In our work, the directly Q-switched 2μm Tm:YAG pulse laser is not realized. As a matter of fact, the Q switch is used to directly switch the 1μm Nd:YAG laser. 相似文献
62.
We have measured the fusion cross sections for ^48Ca+^90,96Zr around the Coulomb barrier and presented them along with the experimental data of ^40Ca+^90,96Zr. The experimental results are compared with the improved quantum molecular dynamics model calculations. It is shown in comparison that the dynamical effects play an important role in the sub-barrier fusion reaction 相似文献
63.
64.
The angular distributions of elastic scattering for the ^6Li +^208Pb system have been measured at several energies around the Coulomb barrier. The parameters of optical potential are extracted by means of a phenomenological optical model analysis. It is found that the real and imaginal potentials show a pronounced energy dependence. The behaviour of the potential at the nearly especially sub-barrier energies in the ^6Li+^208Pb system is quite different from the results of some previous reports observed in other systems, such as ^19F+^208Pb and ^16O+^208Pb. This unusual threshold phenomenon indicates that breakup channel is strongly coupled with the elastic channel and has obvious effects on optical potential. 相似文献
65.
Distinct Superconducting Gap on Two Bilayer-Split Fermi Surface Sheets in Bi_2Sr_2CaCu_2O_(8+δ) Superconductor 下载免费PDF全文
High resolution laser-based angle-resolved photoemission measurements are carried out on an overdoped superconductor Bi_2Sr_2CaCu_2O_(8+)with a_(c )of 75 K.Two Fermi surface sheets caused by bilayer splitting are clearly identified with rather different doping levels:the bonding sheet corresponds to a doping level of 0.14,which is slightly underdoped while the antibonding sheet has a doping of 0.27 that is heavily overdoped,giving an overall doping level of 0.20 for the sample.Different superconducting gap sizes on the two Fermi surface sheets are revealed.The superconducting gap on the antibonding Fermi surface sheet follows a standard d-wave form while it deviates from the standard d-wave form for the bonding Fermi surface sheet.The maximum gap difference between the two Fermi surface sheets near the antinodal region is~2 meV.These observations provide important information for studying the relationship between the Fermi surface topology and superconductivity,and the layer-dependent superconductivity in high temperature cuprate superconductors. 相似文献
66.
光学元件中的杂质和缺陷会引起其激光损伤阈值的大幅降低,现阶段这一问题已成为激光装置向高功率、高能量方向发展的“瓶颈”,亟待解决。在对光学元件激光损伤的研究中发现,用低于光学元件损伤阈值的激光对元件表面进行预处理,可以有效提高光学元件的抗激光损伤能力。对激光预处理技术的提出背景、定性作用机理、定量理论模型及国内外技术应用现状进行了概述。并且介绍了一种可在薄膜制备过程中进行原位实时激光预处理的新型薄膜制备技术。最后指出,激光预处理技术作为一种无污染,可有效改善光学薄膜、光学玻璃、光学晶体元件损伤阈值的最有效方法之一,其作用机理、实用化、仪器化还有待进一步发展。 相似文献
67.
使用两块大面积平行板雪崩计数器,测量了近垒及垒下28Si+174Yb熔合裂变碎片质量-角度关联分布及质量分布。质量-角度二维图显示在该反应能量区间内并没有发现明显的准裂变成分。运用单高斯曲线拟合了裂变碎片的质量分布并抽取了质量宽度。结果表明:在库仑势垒以上,质量宽度随着反应能量的升高而增大;在库仑势垒以下能区,发现质量宽度随着反应能量的降低而呈现轻微增大的趋势。运用鞍点统计模型对本次实验数据拟合发现,需用比文献给出的更大的刚度系数才能重现实验结果,其物理原因还需要进一步研究。In order to study the fission mechanism, the mass distributions and mass-angle distributions of the fission fragments for 28Si+174Yb were measured near the Coulomb barrier. The mass-angle correlations do not indicate any possible quasi-fission events in this bombarding energy range. The mass distributions were fitted by the single Gaussian distribution and then the mass widths were extracted. At above-barrier energies, the mass widths were found to increase with the energy. However, the mass widths show slight increase with decreasing energy below the barrier. Additionally, the mass widths can not be reproduced in the framework of the saddle statistic model with the given parameter, so further study is still needed. 相似文献
68.
We report a Q-switched 2-μm Tm:YAG laser based on intracavity-pumped by a 1064-nm Nd:YAG laser operating at room temperature for the first time. An average output power of 5.1W is obtained with the repetition rate of 30kHz and a pulse width of 300ns. In addition, we demonstrate a 12.5-W continuous-wave 2-μm Tm:YAG laser, which is, to our best knowledge, the highest power for intracavity-pumping configuration. 相似文献
69.
高祺锐 徐新星 周小红 孙立杰 梁鹏飞 刘嘉健 林承键 李晓菁 李智焕 吴鸿毅 杨彦云 王建松 王东玺 蓝乙华 马朋 段芳芳 高志浩 胡强 白真 马军兵 王建国 钟福鹏 武晨光 罗迪雯 蒋颖 刘洋 侯东升 李忍 马南茹 马维虎 石国柱 余功明 D.Patel 金树亚 王煜峰 余悦超 周清武 王鹏 胡力元 王翔 臧宏亮 李朋杰 朱浩钒 林喆阳 赵青青 杨磊 温培威 杨峰 贾会明 张高龙 潘敏 汪小雨 孙浩瀚 胡正国 陈若富 柳敏良 杨维青 《原子核物理评论》2021,(2):117-122
在兰州重离子研究装置上,依托兰州放射性束流线,产生、分离和鉴别了同位旋第三分量TZ=?2的近质子滴线核28 S,并通过使用包括双面硅条探测器和高纯锗探测器在内的探测阵列,开展了28 S的β延迟γ衰变测量.实验准确测量了28 S衰变中的5条β延迟γ射线,得到了子核28 P相应能级的能量.首次提取出了β衰变布居到28P低激... 相似文献
70.
线性分式规划优化分析的元模型方法 总被引:2,自引:0,他引:2
1引言线性分式规划(LFP): min f(x)=(p~Tx α)/(q~Tx β) s.t. Ax=b (1) x≥0有着重要的应用背景,特别在经济管理中受到广泛关注.例如,以净收益率为优化目标函数的海洋运输问题;当价格系数为随机变量时,优化目标为获得满意的收益水平概率最大的资源分配问题等[11].线性分式规划是一类特殊的非线性规划,除一般的非线性规划求解方法外,它还有一些特殊的专用算法.这里,我们要考虑的问题是;当右端资源约束向量在一定范围内(即L≤b≤U,L,U分别为b的下界和上界)变化时,目标函数的最优值如何变化?我们把这一问题称之为线性分式规划的优化分析. 相似文献