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THE ANALYSIS OF INTERLAMINAR STRESSES FOR COMPOSITE LAMINATED SHALLOW SHELLS WITH INTERFACIAL DAMAGE

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Acta Mechanica Solida Sinica 2011年第6期24卷 539-555页

作者： Yiming Fu sheng li Yiqi mao College of Mechanics and Aerospace Hunan University Changsha 410082 China

Based on the general six-degrees-of-freedom plate theory towards the accurate stress analysis and nonlinear theory of shallow shells, considering the damage effect of the interlaminar in- terface and using the variation principle, the three-dimensional non-linear equilibrium differential equations of the laminated shallow shells with interfacial damage are derived. Then, considering a simply supported laminated shallow shell with damage and under normal load, an analytical solution is presented by using finite difference method to obtain the interlaminar stresses. Numer- ical results show, the stiffness of the shell is weakened, greater absolute values of displacements as well as smaller interlaminar stresses are obtained by interfacial damage. When the interfacial damage is further increased, delamination occurs obviously under normal pulling load and pure shear slip occurs under normal pressure load. The portion of the load undertaken by the two sides of the interface is more different. Different mechanical behaviors are shown in both sides of the interface, and the discontinuation of stresses and displacements takes place in the interface.

关键词： laminated shallow shells geometric nonlinearity accurate stress analysis interracialdamage inter-laminar stresses

Synthesis and mesomorphic properties of bent-shaped molecule with low bent-angle central core and long alkylthio tail

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Chinese Chemical Letters 2011年第9期22卷 1111-1114页

作者： Xiao Dong li mao sheng Zhan Kai Wang School of Material Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China

Two homologous series of bent-shaped molecules composed of low bent-angle naphthalene central core and long alkoxy tail or alkylthio tail, N（1,7）-n-OPIMB and N（1,7）-n-SP1MB （n = 20, 22）, respectively, were synthesized. The mesomorphic properties were investigated by differential scanning calorimetry （DSC）, polarizing optical microscopy （POM） and X-ray diffraction （XRD）. Compared to the direct transition from the isotropic phase to the chiral B4 phase examined in N（1,7）-n-OPIMB, N（1,7）-n-SPIMB exhibited a rare Iso-Ncol-Colh-B4 phase sequence. The combination of the asymmetric low bent-angle 1,7-naphathalene central core and the flexible long alkylthio tail is considered to play an important role in the formation of such a novel phase sequence.

关键词： Bent-shaped liquid crystal Alkylthio tail Mesomorphic behaviour

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BIM技术在钢结构工程施工中的应用探讨

工程建设与设计 2024年第8期 88-90页

作者：闫飞李茂省于风仙李波北京东方雨虹防水技术股份有限公司北京100000 中科建通工程技术有限公司北京100000

总结了钢结构工程施工的难点与常见问题,详细介绍了BIM技术在可视化、信息共享、方案调整等方面的特点,探讨BIM技术在钢结构工程施工中的应用,分析了BIM技术在钢结构工程施工中的优势与局限,旨在解决施工中的难点问题,提高施工效率和质量。

关键词：钢结构工程 BIM技术应用探讨施工质量

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乙二醇锑中锑含量分析方法比较

聚酯工业 2024年第1期37卷 1-3页

作者：李玉萍李茂生石海龙中国石油化工股份有限公司洛阳分公司河南洛阳471012

介绍了聚酯催化剂乙二醇锑中锑含量分析方法,从分析技术原理、实验设备材料、影响因素、经济适用性等方面进行了对比分析。对比结果表明,3种分析方法适用于不同的分析条件,不同的生产企业和检测单位可以根据自身的需要建立适合自己企业... 详细信息

介绍了聚酯催化剂乙二醇锑中锑含量分析方法,从分析技术原理、实验设备材料、影响因素、经济适用性等方面进行了对比分析。对比结果表明,3种分析方法适用于不同的分析条件,不同的生产企业和检测单位可以根据自身的需要建立适合自己企业的分析方法。文章的研究内容对聚酯催化剂乙二醇锑中锑含量分析方法的选择具有一定的指导意义,可为相关领域的研究提供一定的参考。

关键词：锑含量分光光度法滴定法 X射线荧光法

Statistical Properties of a Blazar Sample and Comparison of HBLs, LBLs and FSRQs

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Chinese Journal of Astronomy and Astrophysics 2005年第5期5卷 471-486页

作者： li-sheng mao Guang-Zhong Xie Jin-Ming Bai Hong-Tao liu Yunnan Observatory National Astronomical Observatories Chinese Academy of SciencesKunming 650011 Graduate University of Chinese Academy of Sciences Beijing 100049 Yunnan Astrophysics Center Yunnan University Kunming 650091

Making use of the 2MASS Data Release, we have searched for nearinfrared （JHK） counterparts to 268 blazars from Donato et al. and obtained 238 counterparts within 5＇＇ in the area covered by 2MASS. It provides us a sample with infrared data several times larger than the previous one of the same kind. Based on our sample and the sample by Donato et al., we have compared in detail the properties of HBLs, LBLs and FSRQs from five aspects and found that HBLs are significantly different from LBLs and FSRQs while LBLs are not obviously different from FSRQs. Our results strongly support the division of BL Lac objects into the high-frequency peaked （HBL） and low-frequency peaked （LBL） objects introduced by Padovani ＆ Giommi and show that HBLs and LBLs are two kinds of blazar having different physical properties.

关键词： BL Lacertae objects: general-infrared: galaxies - methods: statistical

Changes of the Nuclear Charge Distribution of Nd from Optical Isotope Shifts

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Chinese Physics Letters 2001年第7期18卷 903-905页

作者： MA Hong-liang li mao-sheng YANG Fu-Jia Department of Physics Shanghai UniversityShanghai 200436 Institute of Applied Physics and Computational Mathematics Beijing 100088 Institute of Modern Physics Fudan UniversityShanghai 200433

The isotope shifts and hyperfine structures of seven optical transitions for all seven stable isotopes of Nd II were measured by using collinear fast-ion-beam laser *** nuclear parameterλwas obtained from the measured optical isotope shifts for all seven stable isotopes with improved ***λvalues were analysed by using the Fermi distribution for the nuclear charge *** values of δ,δand δwere determined.

关键词： spectroscopy. density. transitions

The influences of perforating phase and bedding planes on the fracture deflection in laminated shale

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Petroleum Science 2024年第2期21卷 1221-1230页

作者： Ming-Zhe Gu mao sheng Xiao-Ying Zhuang Xin-Yi li Gen-sheng li National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China College of Petroleum Engineering China University of PetroleumBeijing102249China College of Civil Engineering Tongji UniversityShanghai200092China

The perforating phase leads to complex and diverse hydraulic fracture propagation behaviors in laminated shale formations. In this paper, a 2D high-speed imaging scheme which can capture the interaction between perforating phase and natural shale bedding planes was proposed. The phase field method was used to simulate the same conditions as in the experiment for verification and hydraulic fracture propagation mechanism under the competition of perforating phase and bedding planes was *** results indicate that the bedding planes appear to be no influence on fracture propagation while the perforating phase is perpendicular to the bedding planes, and the fracture propagates along the perforating phase without deflection. When the perforating phase algins with the bedding planes, the fracture initiation pressure reserves the lowest value, and no deflection occurs during fracture propagation. When the perforating phase is the angle 45°, 60°and 75°of bedding planes, the bedding planes begin to play a key role on the fracture deflection. The maximum deflection degree is reached at the perforating phase of75°. Numerical simulation provides evidence that the existence of shale bedding planes is not exactly equivalent to anisotropy for fracture propagation and the difference of mechanical properties between different shale layers is the fundamental reason for fracture deflection. The findings help to understand the intrinsic characteristics of shale and provide a theoretical basis for the optimization design of field perforation parameters.

关键词： Shale Propagation Perforating Bedding Structure

Micro electrical discharge machining of small hole in TC4 alloy

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Transactions of Nonferrous Metals Society of China 2009年第S02期19卷 434-439页

作者： li mao-sheng CHI Guan-xin WANG Zhen-long WANG Yu-kui DAI li Key Laboratory of Micro-Systems and Micro-Structures Manufacturing of Ministry of Education Harbin Institute of TechnologyHarbin 150001China School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001China

Aiming at machining deeply small holes in TC4 alloy,a series of experiments were carried out on a self-developed multi-axis micro electrical discharge machining(micro-EDM)machine *** improve machining efficiency and decrease relative wear of electrode in machining deeply small hole in TC4 alloy,many factors in micro-EDM,such as polarity,electrical parameters and supplying ways of working fluid were *** results show that positive polarity machining is far superior to negative polarity machining;it is more optimal when open-circuit voltage,pulse width and pulse interval are 130 V,5μs and 15μs respectively on the self developed multi-axis micro-EDM machine tool;when flushing method is applied in micro-EDM,the machining efficiency is higher and relative wear of electrode is smaller.

关键词： TC4 alloy micro electrical discharge machining deeply small hole multi-axis micro-EDM machine tool

A Periodicity Analysis of the light Curve of 3C 454.3

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Chinese Journal of Astronomy and Astrophysics 2006年第4期6卷 421-429页

作者： Huai-Zhen li Guang-Zhong Xie Shu-Bai Zhou Hong-Tao liu Guang-Wei Cha li Ma li-sheng mao National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 Graduate School of Chinese Academy of Sciences Beijing 100049 Yunnan Astronomical Center Yunnan University Kunming 650091 Physics Department Yunnan University Kunming 650091 Physics Department Yunnan Normal College Kunming 650091

We analyzed the radio light curves of 3C 454.3 at frequencies 22 and 37 GHz taken from the database of Metsaeovi Radio Observatory, and found evidence of quasi-periodic activity. The light curves show great activity with very complicated non-sinusoidal variations. Two possible periods, a very weak one of 1.57 ± 0.12 yr and a very strong one of 6.15 ±0.50 yr were consistently identified by two methods, the Jurkevich method and power specmun estimation. The period of 6.15 ± 0.50 yr is consistent with results previously reported by Ciaramella et al. and Webb et al. Applying the binary black hole model to the central structure we found black hole masses of 1.53 × 10^9M⊙ and 1.86 × 10^8M⊙, and predicted that the next radio outburst is to take place in 2006 March and April.

关键词： galaxies: individual (3C 454.3)-- galaxies: fundamental parameters-- methods:data analysis