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Computer simulation studies of the influence of side alkyl chain on glass transition behavior of carbazole trimer

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Science China Chemistry 2017年第3期60卷 377-384页

作者： Chunyang Yu Li Ma Wei Huang Yongfeng Zhou jingui qin Deyue Yan State Key Laboratory of Metal Matrix Composites School of Chemistry & Chemical EngineeringShanghai Jiao Tong University Department of Chemistry Wuhan University

In this work,all-atom molecular dynamics simulations were employed to study the influence of the side alkyl chain on glass transition behavior of several carbazole trimers(CT) in a temperature range from 423 to 183 *** glass transition temperatures were obtained from the break in the slope of the volume-temperature curves and found to agree with the experimental *** short time dynamics of four CT molecules were probed by usingvelocity autocorrelation functions and mean-square *** current studies showed that the dynamics of CT systems can be easily interpreted through the cage ***,the investigation of the torsional autocorrelation function and P_(2-state)/P_(3-state) functions showed that the rotational barriers of side chains can slow down the conformational relaxation and lead to stronger temperature dependence of conformational *** relaxation time,characteristic time of P_(2-state)(t) and P_(3-state)(t) functions were all found to have Arrhenius-type temperature dependence.

关键词： carbazole trimer molecular dynamics simulation glass transition relaxation time

Research progress on mid-IR nonlinear optical crystals with high laser damage threshold in China

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中国化学前沿:英文版 2011年第1期6卷 1-8页

作者： Tianxiang ZHU Xingguo CHEN jingui qin Department of Chemistry and Hubei Key Laboratory on Organic and Polymeric Opto-electronic Materials Wuhan UniversityWuhan 430072China

Nonlinear optical(NLO)crystals have been playing an increasingly important role in laser science and *** NLO crystals used in the middle infrared(mid-IR)region,compared with the NLO crystals in the other wavelength regions,are still not good enough for the application of high-energy *** main defect is that their laser damage thresholds(LDT)are *** scientists have made a lot of important contributions to the UV and visible NLO *** the last decade,they also did a lot of work on the mid-IR NLO *** main purpose of these researches is to increase the LDT and simultaneously balance the other *** paper presents a brief summary of their research progress in this topic on three types of materials:chalcogenides,oxides,and *** emphasis is put on the design strategy and quality control of the crystals.

关键词： nonlinear optical(NLO)crystals laser damage threshold(LDT) mid-IR region design crystal growth

A structurally ordered thiophene-thiazole copolymer for organic thin-film transistors

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Science China Chemistry 2012年第5期55卷 760-765页

作者： CHEN DuGang ZHAO Yan ZHONG Cheng YU Gui LIU YunQi qin jingui Department of Chemistry and Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan UniversityWuhan 430072China Beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of SciencesBeijing 100190China

This paper reports a new donor-acceptor copolymer semiconductor, PTBTh, comprising bithiophene and bithiazole where the regular coplanar structure and the intramolecular charge transfer are expected to increase the opportunity for --- stacking and charge transport. The AFM image shows lamellar stacking of the polymer on the surface. The field-effect transistor (FET) properties of PTBTh have been evaluated by a bottom-contact/bottom-gate TFT configuration. The device showed a high hole mobility of 1.14×10-2 cm2 V-1 s-1 and a current on/off ratio of 3×105 with the polymer thin film annealed at a mild temperature of 120 ℃ when measured under ambient conditions.

关键词： thin-film transistors copolymer mobility atomic force microscopy

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高速物体撞击过程理论研究

长春理工大学学报（自然科学版） 2024年第2期47卷 10-15页

作者：刘景良覃金贵骆强陈薪羽长春理工大学物理学院长春130022 中国空气动力研究与发展中心超高速空气动力研究所绵阳621000 中国兵器工业第二〇三研究所西安710000

基于现有高速运动物体模型的研究现状,以分析高速物体撞击目标物这一过程为目的,建立了适用于撞击过程的地面坐标系、撞击物坐标系以及撞击物速度坐标系,并推演了相关坐标系之间的转换关系。以此为基础,基于撞击作用原理建立了撞击过程... 详细信息

基于现有高速运动物体模型的研究现状,以分析高速物体撞击目标物这一过程为目的,建立了适用于撞击过程的地面坐标系、撞击物坐标系以及撞击物速度坐标系,并推演了相关坐标系之间的转换关系。以此为基础,基于撞击作用原理建立了撞击过程的理论模型。模拟计算了撞击物形状、撞击角度以及目标物厚度等条件的变化对撞击效果的影响。经理论计算得到了在撞击过程中,撞击角度越贴近正面,击穿效果越好,难度越小;目标物的厚度越大,击穿难度越高的结论。为高速物体击穿损伤过程的研究提供了理论依据。

关键词：高速物体损伤理论撞击效果撞击过程

Design, synthesis and nonlinear optical properties of “dendronized hyperbranched polymers”

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Chinese Science Bulletin 2013年第22期58卷 2753-2761页

作者： WU WenBo HUANG LiJin FU YingJie YE Cheng qin jingui LI Zhen Department of Chemistry Wuhan University Institute of Chemistry Chinese Academy of Sciences

A new type of dendritic polymer, named dendronized hyperbranched polymer (DHP), was prepared successfully by the macro-monomer approach. Thanks to the perfect 3D isolation effects, DHPG1 exhibited good NLO property with d 33 value of 133 pm/V, higher than its analogues of dendronized polymer and dendrimer, and its stability of NLO effect was also enhanced.

关键词：树枝状聚合物非线性光学性质超支化聚合物柱状非线性光学效应设计合成 DHP

Two-photon absorption in V-type chromophores with electron-rich heterocyclevinylene bridges

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Science China Chemistry 2011年第4期54卷 625-630页

作者： LI QianQian ZHONG AoShu LIU HaiJie PENG Ming LIU Jun PEI ZhiGuo HUANG ZhenLi qin jingui LI Zhen Department of Chemistry Hubei Key Laboratory on Organic and Polymeric Opto-Electronic MaterialsWuhan UniversityWuhan 430072China Key Laboratory of Biomedical Photonics of Ministry of Education Huazhong University of Science and Technology Wuhan 430074China

A series of V-type chromophores with electron-rich heterocyclevinylene bridges have been synthesized via Wittig-Horner-Emmons and Vilsmeier *** the target chromophores showed strong one-photon and two-photon excited emission,and their electron properties could be tuned by using different heterocycles such as furan,thiophene and pyrrole moieties in *** maximum two-photon absorption (TPA) cross sections occurred at 760 nm and were measured to be in the range of 400-800 GM.

关键词： two-photon absorption electron-rich heterocycle chromophore

高速动能弹撞击装甲结构引起的螺栓连接失效及部件过载损伤研究

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装备环境工程 2024年第1期21卷 9-18页

作者：覃金贵王马法潘瑛刘廷国李润蔚刘吉安黄洁中国空气动力研究与发展中心超高速空气动力研究所四川绵阳621000 西安现代控制技术研究所西安710065

目的验证和揭示高速动能弹对装甲结构的损伤机理。方法聚焦高速动能弹打击装甲目标时,弹道冲击造成的靶标结构连接失效及部件过载损伤这2种损伤效应,以典型螺栓连接为研究对象,采用高速球形弹丸撞击螺栓连接结构的小尺寸试验对数值模... 详细信息

目的验证和揭示高速动能弹对装甲结构的损伤机理。方法聚焦高速动能弹打击装甲目标时,弹道冲击造成的靶标结构连接失效及部件过载损伤这2种损伤效应,以典型螺栓连接为研究对象,采用高速球形弹丸撞击螺栓连接结构的小尺寸试验对数值模拟方法和材料模型参数进行校验。在此基础上,采用数值模拟和冲击响应谱分析方法对高速动能弹打击全尺寸坦克进行模拟分析,获得撞击过程螺栓连接失效特征、主要影响因素及坦克典型位置部件的冲击加速度曲线和冲击响应谱曲线。结果在小尺寸试验中,动能输入为0.042MJ时,螺栓连接未发生失效;但25.6MJ动能输入全尺寸坦克时,螺栓发生断裂而使连接失效。数值模拟结果揭示了螺栓发生断裂的主要原因。结论输入动能大小、连接螺栓直径、模拟设备部件质量和撞击位置为螺栓是否断裂的主要影响因素。坦克某些位置的冲击响应谱曲线高于军用标准给出的临界曲线的下限甚至上限,表明这些位置的部件因高过载损伤导致失效的概率较高。

关键词：高速动能弹装甲目标弹道冲击螺栓连接失效部件过载损伤冲击响应谱

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High-Pressure Behavior of Ferromagnesite(Mg_(0.81)Fe_(0.19))CO_(3)by Synchrotron X-Ray Diffraction and Raman Spectroscopy up to 53 GPa

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Journal of Earth Science 2024年第2期35卷 525-535页

作者： Lin Liang Guibin Zhang Shengxuan Huang Jingjing Niu Dongzhou Zhang jingui Xu Wen Liang Shan qin Key Laboratory of Orogenic Belts and Crustal Evolution MOEand School of Earth and Space SciencesPeking UniversityBeijing100871China CAS Center of Excellence in Tibetan Plateau Earth Sciences and Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing100101China Hawai’i Institute of Geophysics and Planetology School of Ocean and Earth Science and TechnologyUniversity of Hawai’i at ManoaHawai’i96822USA Key Laboratory of High Temperature and High Pressure Study of the Earth’s Interior Institute of GeochemistryChinese Academy of SciencesGuiyang550081China

Ferromagnesite(Mg,Fe)CO_(3)with 20 mol%iron is a potential host mineral for carbon transport and storage in the Earth *** high-pressure behavior of synthetic ferromagnesite(Mg_(0.81)Fe_(0.19))CO_(3)up to 53 GPa was investigated by synchrotron X-ray diffraction(XRD)and Raman *** iron bearing carbonate underwent spin transition at around 44–46 GPa accompanied by a volume collapse of 1.8%,which also demonstrated a variation in the dνi/dP slope of the Raman *** pressure-volume data was fitted by a third-order Birch-Murnaghan equation of state(BM-EoS)for the high spin *** best-fit K_(0)=108(1)GPa and K_(0)'=4.2(1).Combining the dνi/dP and the K_(0),the mode Grüneisen parameters of each vibrational mode(T,L,ν4 andν1)were *** effects of iron concentration on the Mg_(1−x)Fe_(x)CO_(3)system related to high-pressure compressibility and vibrational properties are *** results expand the knowledge of the physical properties of carbonates and provide insights to the potential deep carbon host.

关键词： ferromagnesite synchrotron XRD Raman spectroscopy high pressure geochemistry mineral

一种连有C_(60)功能基团的聚磷腈的合成

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化学学报 2003年第8期61卷 1335-1337页

作者：李振秦金贵武汉大学化学与分子科学学院武汉430072

采用一种后功能化的方法合成了一种连有C60 侧基的聚磷腈高分子 ,即首先合成了连有苄溴基团的聚磷腈 ,然后将苄溴基团转换为叠氮基团 ,再合成连有C60 侧基的聚磷腈高分子 .通过核磁、红外、紫外可见光谱、分子量测定等手段对所得高分子... 详细信息

采用一种后功能化的方法合成了一种连有C60 侧基的聚磷腈高分子 ,即首先合成了连有苄溴基团的聚磷腈 ,然后将苄溴基团转换为叠氮基团 ,再合成连有C60 侧基的聚磷腈高分子 .通过核磁、红外、紫外可见光谱、分子量测定等手段对所得高分子进行了鉴定 .

关键词： C60 功能基团聚磷腈合成功能材料高分子结构表征叠氮基团