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Organic Chemistry Frontiers 2022年第1期9卷 88-94页

作者： yao-Bin Shen jian-qiang Zhao zhen-Hua Wang yong You Ming-qiang Zhou Wei-Cheng Yuan National Engineering Research Center of Chiral Drugs Chengdu Institute of Organic ChemistryChinese Academy of SciencesChengdu610041China Innovation Research Center of Chiral Drugs Institute for Advanced StudyChengdu UniversityChengdu 610106China University of Chinese Academy of Sciences Beijing100049China

The reaction of 2-pyridylacetates andα,β-unsaturated pyrazolamides with DBU as the catalyst has been developed.A range of unexplored multisubstituted 2,3-dihydro-4H-quinolizin-4-ones are obtained with satisfactory yields(up to 94%)and excellent diastereoselectivities(all cases>20:1 dr)via a dearomative[3+3]annulation *** practical method also features transition metal free,mild reaction conditions,wide functional group tolerance,easy scale-up synthesis,and versatile further derivatization.

关键词： process substituted unsaturated

基于反向比例解析的近红外光谱定量模型快速构建方法

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分析测试学报 2024年第5期43卷 792-797页

作者：张晓兵徐志强钟永健朱宏福李峥张军詹映彭云发刘建国浙江中烟工业有限责任公司技术中心浙江杭州310024 上海创和亿电子科技发展有限公司上海200082

为解决光谱漂移问题,该研究设计了一种基于反向比例解析的近红外光谱定量模型方法。以烟叶近红外光谱和烟碱含量为研究对象,将数据划分为训练集和测试集。通过计算训练集光谱与测试集光谱的相关性并按照高低排序,选择前20%的光谱,运用... 详细信息

为解决光谱漂移问题,该研究设计了一种基于反向比例解析的近红外光谱定量模型方法。以烟叶近红外光谱和烟碱含量为研究对象,将数据划分为训练集和测试集。通过计算训练集光谱与测试集光谱的相关性并按照高低排序,选择前20%的光谱,运用约束规划的方法,计算测试集的拟合系数,得到测试集光谱的估计值。结果显示,使用反向比例解析法建立的模型的平均绝对误差为0.3466,预测标准偏差为0.4252,相关系数为0.7932,优于PLS模型。反向光谱比例解析可以有效解决光谱漂移问题,实现烟草中烟碱含量的准确预测,为烟碱的有效测量提供参考。

关键词：反向比例近红外光谱相关性拟合系数加权

Dynamic response of UHMWPE plates under combined shock and fragment loading

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Defence Technology(防务技术) 2023年第9期27卷 9-23页

作者： chun-zheng Zhao Lu-Sheng qiang Rui Zhang Qian-Cheng Zhang Jun-yang Zhong zhen-Yu Zhao Tian jian Lu State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing210016PR China MIIT Key Laboratory of Multi-functional Lightweight Materials and Structures(MLMS) Nanjing University of Aeronautics and AstronauticsNanjmg 210016PR China State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhai430200PR China School of Aerospace Xi'an Jiaotong UniversityXi'an710049PR Chuia

Ultra-high molecular weight polyethylene(UHMWPE)fiber composite has been extensively used to construct lightweight protective structures against ballistic impacts,yet little is known about its performance when subjected to combined blast and fragment *** upon a recently developed laboratory-scale experimental technique to generate simulated combined loading through the impact of a fragment-foam composite projectile launched from a light gas gun,the dynamic responses of fullyclamped UHMWPE plates subjected to combined loading were characterized experimentally,with corresponding deformation and failure modes compared with those measured with simulated blast loading ***,to explore the underlying physical mechanisms,three-dimensional(3D)numerical simulations with the method of finite elements(FE)were systematically carried *** predictions compared favorably well with experimental measurements,thus validating the feasibility of the established FE *** to the case of blast loading alone,combined blast and fragment loading led to larger maximum deflections of clamped UHMWPE *** position of the FSP in the foam sabot affected significantly the performance of a UHMWPE target,either enhancing or decreasing its ballistic *** the blast loading and fragment impact arrived simultaneously at the target,its ballistic resistance was superior to that achieved when subjected to fragment impact alone,and benefited from the accelerated movement of the target due to simultaneous blast loading.

关键词： UHMWPE composite Ballistic performance Combined blast and fragment loading Impact test Finite element simulation

Characteristics of Welding Crack Defects and Failure Mode in Resistance Spot Welding of DP780 Steel

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Journal of Iron and Steel Research International 2016年第10期23卷 1104-1110页

作者： Xiao-pei WANG yong-qiang ZHANG jian-bin JU jian-qiang ZHANG jian-wei yang Shougang Research Institute of Technology Beijing 100043 China College of Science China University of Petroleum (Beijing) Beijing 102249 China

The mechanical properties of welded joints in resistance spot welding of DP780 steel were tested,and three different types of welding cracks in welded joints were investigated by optical microscopy,scanning electron microscopy and electron back-scattered ***,the failure mode of the welded joints in shear tensile test was *** is found the shear tensile strength of welded joints can be greatly improved by adding preheating current or tempering *** surface crack in welded joint is intergranular fracture,while the inner crack in welded joint is transgranular fracture,and the surface crack on the edge of the electrode imprint can be improved by adding preheating current or tempering *** traditional failure mode criterion advised by American Welding Society is no longer suitable for DP780 spot welds and the critical nugget size suggested by Pouranvari is overestimated.

关键词： resistance spot welding mechanical property crack defect failure mode DP780 steel

One-neutron stripping process in the^(209)Bi(^(6)Li,^(5)Li)^(210)Bi*reaction reaction

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Nuclear Science and Techniques 2024年第6期35卷 120-129页

作者： Gao-Long Zhang zhen-Wei Jiao Guang-Xin Zhang E.N.Cardozo B.Paes Shi-Peng Hu jian-qiang Qian Daniele Mengoni Wei-Wei Qu Cong-Bo Li Yun zheng Huan-Qiao Zhang Hui-Bin Sun Nan Wang chun-Lei Zhang J.J.Valiente-Dobón D.Testov M.Mazzocco A.Gozzelino C.Parascandolo D.Pierroutsakou M.La Commara A.Goasduff D.Bazzacco D.R.Napoli F.Galtarossa F.Recchia A.Illana S.Bakes I.Zanon S.Aydin Gde Angelis M.Siciliano R.Menegazzo S.M.Lenzi S.Akkoyun L.F.Canto J.Lubian School of Physics Beihang UniversityBeijing 100191China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China Instituto de Física Universidade Federal Fluminense24210-340 NiteróiRio de JaneiroBrazil Laboratorio TANDAR Comisión Nacional de Energía AtómicaBKNA1650 San MartíınArgentina Institute for Advanced Study in Nuclear Energy and Safety Shenzhen UniversityShenzhen 518060China Shenzhen Key Laboratory of Research and Manufacture of High Purity Germanium Materials and Fetectors Shenzhen UniversityShenzhen 518060China INFN Sezione di PadovaPaduaItaly Dipartimento di fisica Astronomia dell’Universita di padova PaduaItaly State Key Laboratory of Radiation Medicine and Protection School of Radiation Medicine and ProtectionSoochow UniversitySuzhou 215123China China Institute of Atomic Energy Beijing 102413China The Key Laboratory of Beam Technology and Material Modification of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Laboratori Nazionali di Legnaro INFN35020 LegnaroItaly INFN Sezione di Napoli80126 NaplesItaly Dipartimento di Farmacia Universitàdi Napoli“Federico II”80131 NaplesItaly Department of Natural and Mathematical Sciences Faculty of EngineeringTarsus University33480 MersinTurkey Physics Division Argonne National LaboratoryLemontILUSA Department of Physics Sivas Cumhuriyet UniversitySivasTurkey Instituto de Física Universidade Federal do Rio de JaneiroRio de Janeiro CP 6852821941-972Brazil

One-neutron stripping process between^(6)Li and^(209)Bi was studied at 28,30,and 34 MeV using the in-beamγ-ray spectroscopy ***γ-γcoincident analysis clearly identified twoγ-rays feeding the ground and long-lived isomeric states,which were employed to determine the cross *** one-neutron stripping cross sections were similar to the cross sections of complete fusion in the^(6)Li+^(209)Bi system,but the one-neutron stripping cross sections decreased more gradually at the sub-barrier region.A coupled-reaction-channel calculation was performed to study the detailed reaction mechanism of the one-neutron stripping process in^(6)*** calculations indicated that the first excited state of 5 Li is critical in the actual one-neutron transfer mechanism,and the valence proton of 209Bi can be excited to the low-lying excited state in(^(6)Li,^(5)Li)reaction,unlike in the(d,p)reaction.

关键词： Transfer reaction Weakly bound nuclei Cross section

Dissipative quantum phase transition in a biased Tavis-Cummings model

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Chinese Physics B 2020年第4期29卷 296-302页

作者： zhen Chen Yueyin Qiu guo-qiang Zhang jian-qiang You Quantum Physics and Quantum Information Division Beijing Computational Science Research CenterBeijing 100193China Interdisciplinary Center of Quantum Information and Zhejiang Province Key Laboratory of Quantum Technology and Device Department of Physics and State Key Laboratory of Modern Optical InstrumentationZhejiang UniversityHangzhou 310027China Laboratory of Quantum Information Institute for Quantum Information and SpintronicsSchool of ScienceChongqing University of Posts and TelecommunicationsChongqing 400065China

We study the dissipative quantum phase transition(QPT)in a biased Tavis–Cummings model consisting of an ensemble of two-level systems(TLSs)interacting with a cavity mode,where the TLSs are pumped by a drive *** our proposal,we use a dissipative TLS ensemble and an active cavity with effective *** the weak drive-field limit,the QPT can occur under the combined actions of the loss and gain of the *** to the active cavity,the QPT behavior can be much differentiated even for a finite strength of the drive field on the TLS ***,we propose to implement our scheme based on the dissipative nitrogen-vacancy(NV)centers coupled to an active optical cavity made from the gainmedium-doped ***,we show that the QPT can be measured by probing the transmission spectrum of the cavity embedding the ensemble of the NV centers.

关键词： quantum phase transition dissipative ensemble of two-level systems active optical cavity Tavis-Cummings model

Searching for^(76)Ge neutrinoless double beta decay with the CDEX-1B experiment

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Chinese Physics C 2024年第10期48卷 11-22页

作者： Bing-Tao Zhang Jun-zheng Wang Li-Tao yang Qian Yue Ke-Jun Kang Yuan-Jing Li Hai-Peng An C.Greeshma jian-Ping Chang Yun-Huan Chen jian-Ping Cheng Wen-Han Dai Zhi Deng Chang-Hao Fang Xin-Ping Geng Hui Gong Qiu-Ju guo Xu-Yuan guo Li He Sheng-Ming He Jin-Wei Hu Han-Xiong Huang Tu-Chen Huang Hai-Tao Jia Xi jiang S.Karmakar Hao-Bin Li jian-Min Li Jin Li Qian-Yun Li ren-Ming-Jie Li Xue-Qian Li Yu-Lan Li Yi-Fan Liang Bin Liao Fong-Kay Lin Shin-Ted Lin Jia-Xuan Liu Shu-Kui Liu Yan-Dong Liu Yu Liu Yuan-Yuan Liu Zhong-Zhi Liu Hao Ma Yu-Cai Mao Qi-Yuan Nie Jin-Hua Ning Hui Pan Ning-chun Qi Jie ren Xi-Chao Ruan Ze She Manoj Kumar Singh Tian-Xi Sun Chang-jian Tang Wei-You Tang yang Tian Guang-Fu Wang Li Wang Qing Wang Yu-Feng Wang Yun-Xiang Wang Henry-Tsz-King Wong Shi-yong Wu Yu-Cheng Wu Hao-yang Xing Rui Xu Yin Xu Tao Xue Yu-Lu Yan Nan Yi chun-Xu Yu Hai-Jun Yu jian-Feng Yue Ming Zeng Zhi Zeng Feng-Shou Zhang Lei Zhang zhen-Hua Zhang zhen-Yu Zhang Kang-Kang Zhao Ming-Gang Zhao Ji-Fang Zhou Zu-Ying Zhou Jing-Jun Zhou Key Laboratory of Particle and Radiation Imaging(Ministry of Education)and Department of Engineering Physics Tsinghua UniversityBeijing 100084 Department of Physics Tsinghua UniversityBeijing 100084 Institute of Physics Academia SinicaTaipei 11529 NUCTECH Company Beijing 100084 YaLong River Hydropower Development Company Chengdu 610051 College of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875 College of Physics Sichuan UniversityChengdu 610065 School of Physics Peking UniversityBeijing 100871 Department of Nuclear Physics China Institute of Atomic EnergyBeijing 102413 Sino-French Institute of Nuclear and Technology Sun Yat-sen UniversityZhuhai 519082 School of Physics Nankai UniversityTianjin 300071 Department of Physics Banaras Hindu UniversityVaranasi 221005 Department of Physics Beijing Normal UniversityBeijing 100875

We operated a p-type point contact high purity germanium(PPCGe)detector(CDEX-1B,1.008 kg)in the China Jinping Underground Laboratory(CJPL)for 500.3 days to search for neutrinoless double beta(0νββ)decay of^(76)Ge.A total of 504.3 kg⋅day effective exposure data was *** anti-coincidence and the multi/single-site event(MSE/SSE)discrimination methods were used to suppress the background in the energy region of interest(ROI,1989–2089 keV for this work)with a factor of 23.A background level of 0.33 counts/(keV⋅kg⋅yr)was *** lower limit on the half life of^(76)Ge 0νββdecay was constrained as T_(1/2)^(0ν)>1.0×10^(23)yr(90%C.L.),corresponding to the upper limits on the effective Majorana neutrino mass:<3.2–7.5 eV.

关键词： neutrinoless double beta decay CDEX point-contact germanium detector ^(76)Ge

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基于文桥振荡器的高Q带通滤波器的设计

兰州理工大学学报 2024年第5期50卷 101-104页

作者：李永安曹剑馨侯婧嫱陕西国际商贸学院信息工程学院陕西西安712046 咸阳师范学院物理与电子工程学院陕西咸阳712000

从单电阻调谐的文桥振荡器出发,首先导出该振荡器的振荡条件和振荡频率,然后给出了二阶带通滤波器的两种设计方案.第一种设计方案的优点是可以实现极点频率的单电阻调节,第二种方案的优点是极点频率和品质因数可正交调节.两种方案均可... 详细信息

从单电阻调谐的文桥振荡器出发,首先导出该振荡器的振荡条件和振荡频率,然后给出了二阶带通滤波器的两种设计方案.第一种设计方案的优点是可以实现极点频率的单电阻调节,第二种方案的优点是极点频率和品质因数可正交调节.两种方案均可实现两个带通输出,均可调节电阻使电路振荡,而且振荡条件和振荡频率均可分别调节.通过计算机仿真证实了所设计的电路正确有效.

关键词：高Q 带通滤波器集成运放文桥振荡器

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盾构克泥效浆液成分与渗透扩散研究

科学技术与工程 2024年第16期24卷 6916-6926页

作者：陈豪张康健史勇陈勇张志强西南交通大学土木工程学院成都610031 重庆交通建设(集团)有限责任公司重庆400010

盾构隧道近接既有结构施工中常采用克泥效工法辅助控制地层位移。克泥效浆液的流变和渗透扩散性能对盾壳外环向间隙的填充效果具有重要影响。基于克泥效浆液X射线衍射试验(X-ray diffraction, XRD)和黏度试验,研究浆液微观成分及流变性... 详细信息

盾构隧道近接既有结构施工中常采用克泥效工法辅助控制地层位移。克泥效浆液的流变和渗透扩散性能对盾壳外环向间隙的填充效果具有重要影响。基于克泥效浆液X射线衍射试验(X-ray diffraction, XRD)和黏度试验,研究浆液微观成分及流变性能。基于多孔介质多相流控制方程,建立砂土中克泥效浆液扩散数值模型,分析浆液配比、地层渗透系数和注浆压力对扩散性能的影响。结合宾汉姆流体砂土渗流公式,验证数值模型的可靠性。结果表明:克泥效浆液成分主要为石英、斜长石、伊利石、正长石,且随A液水粉比增加,斜长石含量增加,伊利石含量减小。克泥效浆液的塑性黏度与屈服强度随A液水粉比的减小而增大,宾汉姆模型对浆液流变曲线的拟合优度大于0.95。克泥效浆液在环向间隙中的填充扩散阶段约为25s,而后再向地层中发生渗透扩散,渗透扩散速度远小于填充扩散。随A液水粉比、地层渗透系数、注浆压力增加,克泥效在地层渗透距离均会增加。

关键词：克泥效宾汉姆流体 X射线衍射(XRD)试验渗透扩散数值模拟

Noncommutative Differential Calculus and Its Application on Discrete Spaces

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Communications in Theoretical Physics 2008年第1期49卷 37-44页

作者： LIU zhen BAI yong-qiang WU Ke guo Han-Ying Center of Mathematical Sciences Zhejiang University Hangzhou 310027 China Department of Mathematics Zhejiang University of Technology Hangzhou 310023China Institute of Mathematics Henan University Kaifeng 475001 China Department of Mathematics Capital Normal University Beijing 100037 China Institute of Theoretical Physics the Chinese Academy of Sciences Beijing 100080China

We present the noncommutative differential calculus on the function space of the infinite set and construct a homotopy operator to prove the analogue of the Poincare lemma for the difference complex. Then the horizontal and vertical complexes are introduced with the total differential map and vertical exterior derivative. As the application of the differential calculus, we derive the schemes with the conservation of symplecticity and energy for Hamiltonian system and a two-dimensional integral models with infinite sequence of conserved currents. Then an Euler-Lagrange cohomology with symplectic structure-preserving is given in the discrete classical mechanics.

关键词： noncommutative differential calculus Poincare lemma horizontal and vertical complexes Euler-Lagrange cohomology