排序方式: 共有43条查询结果,搜索用时 484 毫秒
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各向异性平面含斜裂纹的奇异积分方程方法 总被引:1,自引:0,他引:1
本文应用平面弹性复变方法,将无限各向异性平面中的任意斜裂纹问题归结为求解一组解析函数边值问题,通过构造适当的积分变换将边值问题转化为奇异积分方程,进而应用Lobotto-Chebyshev数值求积公式,求出该奇异积分方程的数值解,并得到了应力强度因子的近似表达式,最后,给出了一些实例的数值结果,对特例的数值结果与精确结果进行比较,吻合的很好。 相似文献
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在600℃温度下,采用液相燃烧法合成了Sr2+、Eu2+和Mn2+三掺的BaMgAl10O17(BAM)蓝绿荧光粉。用XRD、SEM和荧光光谱仪分别分析和表征该荧光粉的物相、形貌和光致发光性能。结果表明,液相燃烧法合成BAM的温度明显低于传统的高温固相合成法;合成的纳米棒均匀、无团聚现象;荧光光谱仪分析表明Eu2+、Mn2+离子间存在能量传递,且Sr2+能有效提高BAM的发光强度,约为固相法制备荧光强度的1.8倍。BAM:0.1Eu2+,0.04Mn2+,0.05Sr2+色坐标为(0.146,0.250),属于蓝绿光。 相似文献
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In this paper,the kinematic fitting with the Lagrange multiplier method has been studied for BESⅢ experiment.First we introduce the Lagrange multiplier method and implement kinematic constraints.Then we present the performance of the kinematic fitting algorithm.With the kinematic fitting,we can improve the resolution of track parameters and reduce the background. 相似文献
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一种新型羧酸-磺酸双功能配体的钴配合物的合成与三维氢键网络结构 总被引:4,自引:0,他引:4
Using the ligand 4-sulfonyl-2,6-naphthalenedicarboxylate (SNDC), a coordination compound [Co(H2O)6]2[Co(SNDC)2(H2O)4]·4H2O(1) was synthesized and characterized by elemental analysis, thermal analysis, IR and single crystal X-ray diffraction structure analysis. The complex crystallizes in the triclinic P1 space group. The crystallographic data are: a=0.722 4(3) nm, b=1.181 2(4) nm, c=1.353 4(5) nm, V=1.039 47(7) nm3, Z=1, Dc=1.795 g·cm-3, R1=0.055 8, wR2=0.148 7. In the complex, the cobalt(Ⅱ) mononuclear anion ([Co(SNDC)2(H2O)4]4-) adopts the six-coordinated octahedral geometry furnished by two carboxylate oxygen atoms from the SNDC ligands and four water oxygen atoms. The cobalt(Ⅱ) mononuclear anions are self-assembled into two-dimensional sheets through hydrogen bonding between coordinated water molecules and carboxylate oxygens and π-π stacking of the aromatic naphthalene moieties. The [Co(H2O)6]2+ cations are intercalated between the layers through additional hydrogen bonds involving coordinated water molecules and sulfonate/carboxylate oxygen atoms. CCDC: 694556. 相似文献
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利用遗传算法优化线性啁啾光栅性能 总被引:3,自引:2,他引:1
针对制作町用于40 Gb/s全光色散补偿的宽带线性啁啾光栅时出现带内群时延纹波波动较大等问题.提出了一种通过设计和改变切趾函数的参量来优化线性啁啾光栅的新方法.该方法实现简单.只需根据需要设计具有不同滚降特性的切趾函数,同时利用遗传箅法来优化切趾参量.结合传输矩阵法经过200代获得了低带内时延纹波的线性啁啾光栅.数值结果验证了采取非对称分段切趾法在保持反射谱宽和平坦性的同时可以抑制带内群时延纹波的优越性.利用该方法制作了反射谱工作带宽为1.06 nm、时延纹波不超过45.60 ps、可用于大容量密集波分复用系统(DWDM)色散补偿的线性啁啾光纤光栅. 相似文献
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梁羽铁 冒亚军 尤郑昀 李卫东 边渐鸣 曹国富 曹学香 陈申见 邓子艳 傅成栋 高原宁 韩磊 韩少卿 何康林 何苗 胡继峰 胡小为 黄彬 黄性涛 贾卢魁 季晓斌 李海波 刘北江 刘春秀 刘怀民 刘颖 刘勇 罗涛 吕绮雯 马秋梅 马想 毛泽普 莫晓虎 宁飞鹏 平荣刚 邱进发 宋文博 孙胜森 孙晓东 孙永昭 田浩来 王纪科 王亮亮 文硕频 伍灵慧 吴智 谢宇广 徐敏 言杰 严亮 姚剑 苑长征 袁野 张长春 张建勇 张雷 张学尧 张瑶 郑阳恒 朱永生 邹佳恒 《中国物理 C》2009,(7)
Cosmic-ray data of 90 M events have been collected and used for calibration,alignment as well as detector tuning. A special tracking algorithm for the BESⅢ muon counter is developed and verified with Monte-Carlo simulation and then further confirmed with the cosmic-ray data. The obtained strip resolutions are in good agreement with the design values. A new alignment approach for the BESⅢ muon counter is confirmed with the cosmic-ray data and proposed to be used in future analysis of experimental data. 相似文献
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莫晓虎 张建勇 张天保 张清江 Achasov Mikhail 傅成栋 Muchnoi Nikolay 秦庆屈化民 王贻芳 吴靖民 徐金强 俞伯祥 《中国物理 C》2009,33(10):914-921
The technique details for measuring radiation dose are expounded. The results of gamma and neutron radiation levels are presented and the corresponding radiation shielding is discussed based on the simplified estimation. In addition, the photon radiation level move as background for future experiments is measured by a NaI(T1) detector. 相似文献
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Zero-Chirp Return-to-Zero Pulses Generation with Two Single-Driver z-Cut Mach-Zehnder Modulators 下载免费PDF全文
A novel method is proposed to suppress the frequency chirp of single-driver z-cut Mach Zehnder modulators. Theoretical analysis shows that by multiplying the output pulses of a half clock frequency driving single-driver z-cut modulator with the one delayed odd multiple bit duration, the frequency chirp can be removed entirely, and return-to-zero (RZ) pulses with duty cycles of about 25% and 56% are obtained. An experimental scheme is proposed to validate the proposed method. The pulses can be obtained by using this scheme. experimental results show that perfect 40 GHz zero-chirp RZ 相似文献