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焦散线法确定应力强度因子的条件

力学季刊 2001年第3期22卷 359-362页

作者：张忠平雷洪利王锋会杨尊袍刘志毅空军工程大学工程学院西安710038 西北工业大学西安710072

基于焦散线的形成原理及合裂纹受力试件在裂尖附近区域的应力分布,得到了焦散线法确定应力强度因子的条件:初始曲线半径与试件厚度之比大于0.5。当满足该条件时,对光学各向同性材料及光学各向异性材料前表面反射的情形,只需测量焦散线... 详细信息

基于焦散线的形成原理及合裂纹受力试件在裂尖附近区域的应力分布,得到了焦散线法确定应力强度因子的条件:初始曲线半径与试件厚度之比大于0.5。当满足该条件时,对光学各向同性材料及光学各向异性材料前表面反射的情形,只需测量焦散线沿横向的最大尺寸便可较精确地确定应力强度因子;而对于光学各向异性材料的透射或后表面反射情形,只有在忽略远场非奇异应力的影响后,才可借助焦散线的横向尺寸近似确定应力强度因子。

关键词：焦散线法应力强度因子裂纹受力试件材料机械构件应力场分布光学各向同性光学各向异性裂尖

Measurement and Evolution of High-quality Development Level of Marine Fishery in China

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Chinese Geographical Science 2022年第2期32卷 251-267页

作者： LI Bo liu zun Institute of Marine Sustainable Development Liaoning Normal UniversityDalian 116029China

High-quality development of marine fisheries provides an important advantage for China to build itself into a maritime power and implement the Blue Granary Plan *** on the concepts of‘new development’,‘food security’,and the six dimensions of‘openness,innovation,coordination,green,sharing,and security’,in this study,we established an evaluation index system for the high-quality development of China’s marine fishery *** applied the entropy method to evaluate the high-quality development level of China’s marine fishery sector from 2000 to 2016 and explored its spatial and temporal evolution *** results indicated that:1)from 2000 to 2016,China’s marine fishery sector was in the primary stage of high-quality development;2)spatially,the highquality development of marine fisheries showed an upward trend in all provinces,autonomous regions,and municipalities in the country(not including Hong Kong,Macao and Taiwan of China),and with time,the distribution pattern changed from single to multi-polarization;3)temporally,the development level of high-quality marine fisheries fluctuated during the study *** 2000 to 2010,the growth rate in openness was relatively slow,but after 2010,it increased ***,innovation is the driving force for high-quality *** green and security factors provide a solid guarantee for high-quality *** the high-quality development of a region,economic development is better coordinated,and the distribution of benefits is more *** study provides a theoretical basis to formulate effective marine fishery policies for the high-quality development of the marine fishery sector in *** the high-quality development and evolution process of marine fishery is conducive to promoting the sustainable development of marine fishery industry,ensuring marine fishery food security,and alleviating global food crisis.

关键词： marine fisheries high-quality development new development concept food security spatiotemporal evolution comprehensive measurement

Synthesis,characterization,and phase transition of an inorganic-organic hybrid compound,[(3-nitroanilinium^＋)(18-crown-6)][IO4^-](CH3OH)

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Chinese Chemical Letters 2017年第2期28卷 297-301页

作者： zun-Qi liu yang liu Yuan Chen Wu-Qiang Zhao Wei-Na Fang Chemical Engineering College Xinjiang Agricultural University Urumqi 830052 China

A novel inorganic-organic hybrid supramolecular compound,[（3-nitroanilinium^＋）（18-crown-6）][IO4]（CH3OH）（1）,was discovered as phase-transition materials displaying dielectric anomalous *** yellow block crystal formed by N-H…O hydrogen bonding that made contact through the cavity of 18-crown-6 was characterized by single-crystal X-ray diffraction,elemental analysis,infrared analysis,thermogravimetric analysis,differential scanning calorimetry,and potential-energy *** scanning calorimetry measurements indicate that the compound experiences a reversible phase transition at around 220 ***-dependent dielectric measurements further confirm the phase ***-energy calculations demonstrate that the phase transition occurs due to the molecular order-disorder rotation of CH3OH,whereas the space grouping of the crystal remains unchanged.

关键词： Phase transition Crystal structure Molecular rotation Dielectric anomaly

Estimation of n-Octanol/water Partition Coeffi-cients(lgK_(ow)) and the Aqueous Solubility(-lg_(Sw)) of all PCDF Congeners by Density Functional Theory

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Chinese Journal of Structural Chemistry 2006年第9期25卷 1134-1140页

作者： yang Guo-Ying YU Jing WANG zun-Yao liu Hong-Xia School of Biological and Chemical Engineering Jiaxing University Jiaxing Zhejiang 314001 China Department of Material and Chemical Engineering Guilin Institute of Technology Guilin Guangxi 541004 China School of the Environment Naniing University Nanjing Jiangsu 210093 China

Optimized calculation of dibenzofuran （DF） and 135 polychlorinated dibenzofurans （PCDFs） was carried out at the B3LYP/6-31G＊ level in GAUSSIAN 98 program. Based on the theoretical linear solvation energy relationship （TLSER） model, the obtained structural parameters were taken as theoretical descriptors to establish the novel quantitative structureproperty relationship （QSPR） model for predicting n-octanol/water partition coefficients （lgKow） of PCDFs. The new model of lgKow achieved in this work contains three variables： energy of the highest occupied molecular orbital （EHOMO）, the most negative atomic partial charge （q^-） and average molecular polarizability （a）, of which R^2= 0.9011 and SD = 0,17 with larger t values. In addition, the variation inflation factors （VIF） of variables in the present model are all less than 5.5, suggesting high accuracy of the lgKow model. And the results of cross-validation test （q^2 = 0.8688） and method validation also show this model exhibits optimum stability and better predictive power than semi-empirical method. At the same time, it is found that the aqueous solubility （-lgSw） has high relative correlation with constant volume molar heat capacity （Cv^0）, of which R^2 = 0.9777 and SD = 0.22. Moreover, lgKow and -lgSw values of all PCDF congeners were predicted respectively.

关键词： polychlorinated dibenzofurans (PCDFs) n-octanol/water partition coefficients (lgKow) aqueous solubility (-lgSw) quantitative structureproperty relationship (QSPR) density functional theory (DFT)

Determination of the Toxicities of 16 Halogenated Benzenes to Photobacterium Phosphoreum and 2D- and 3D-QSAR Studies

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Chinese Journal of Structural Chemistry 2010年第7期29卷 1007-1014页

作者： CAO Si-Tong WANG Xiu liu Hong-Xia yang Guo-Ying WANG zun-Yao Garment andArt Design College Jiaxing University Jiaxing Zhefiang 314001 China Biological and Chemical Engineering College Jiaxing Zhejiang 314001 China

In this paper we take photobacterium phosphoreum （T3） as the experimental bacteria, and determine the half-inhibitory concentration （-1gEC50） against the photobacterium phosphoreum of 16 halogenated benzenes. Using B3LYP method of DFT in the Gaussian 03 program, we obtain the structural and thermodynamic descriptors of 16 halogenated benzenes by fully-optimized calculation at the 6-311G＊＊ level. Taking the structural and thermodynamic descriptors as theoretical descriptors, the 2D QSAR model （R2 = 0.983） was established, which can be utilized to predict -lgEC50 of halogenated benzene according to the corrected linear solvation energy theory based on the experimental data of-lgECs0. In addition, the relationship between the toxicity and 3D spatial structure of the compound is studied by comparing the molecular similarity index analysis （CoMSIA） of 3D-QSAR method. By cross validation, the correlation coefficient q2 of CoMSIA model is 0.687, and the conventional correlation coefficient R2 = 0.958. The model is stable and reliable with great predictive ability. The 3D-QSAR model shows that the toxicity of halogenated benzene compound is mainly affected by the characteristics of hydrophobie field of the substituted halogens.

关键词： halogenated benzene toxicity (-lgEC50) DFT QSAR

Exact Jacobian Elliptic Function Solutions to sinh-Gordon Equation

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Communications in Theoretical Physics 2006年第1期45卷 55-60页

作者： FU zun-Tao liu Shi-Kuo liu Shi-Da School of Physics Peking University Beijing 100871 China State Key Laboratory for Turbulence and Complex Systems Peking University Beijing 100871 China

In this paper, two transformations are introduced to solve sinh-Gordon equation by using the knowledge of elliptic equation and Jacobian elliptic functions. It is shown that different transformations are required in o... 详细信息

关键词： Jacobian elliptic function transformation sinh-Gordon equation

Tunable Luminescence Properties and Elucidating the Electronic Structures of Single-Phase Spherical BaWO 4:Dy^(3+),Tm^(3+),Eu^(3+)Phosphors for Warm-White-Lighting

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Journal of Renewable Materials 2022年第2期10卷 431-451页

作者： zun Bi Ke Jia Yunfei liu Yinong Lyu State Key Laboratory of Materials–Orient Chemical Engineering College of Materials Science and EngineeringNanjing Tech UniversityNanjingChina Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM) NanjingChina Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites NanjingChina

A series of uniform single-phase spherical BaWO 4:Dy^(3+),Tm^(3+),Eu^(3+)phosphors were prepared via a microwave hydrothermal method by using trisodium citrate dehydrate as *** phase structure,morphology and photoluminescence properties were measured by powder X-ray diffraction,scanning electron microscope and fluorescence spectrometer,*** results show that uniform spherical microcrystals with diameters in the range of 2–4μm are *** the phase and morphology of samples are not significantly changed by doping rare earth(RE^(3+))*** the excitation wavelength of 356 and 365 nm,the samples BaWO 4:0.03Dy^(3+),yTm^(3+)can emit cold white *** order to lower the correlated color temperature(CCT)to get a warm white light,the Eu^(3+)ions were doped into BaWO 4:0.03Dy^(3+),0.01Tm^(3+).Especially,under the excitation of 365 nm,BaWO 4:0.03Dy^(3+),0.01Tm^(3+),0.03Eu^(3+)phosphor shew a bright warm white light with color coordi-nate of(0.4013,0.3629)and CCT of 3288 ***,in the BaWO 4:Dy^(3+),Tm^(3+),Eu^(3+)phosphors,the energy transfer mechanism among Dy^(3+),Tm^(3+)and Eu^(3+)ions have been discussed and the change of electron structures have been calculated by first-principles *** results shew that the uniform single-phase spherical BaWO 4:Dy^(3+),Tm^(3+),Eu^(3+)phosphors could be favorable candidates in warm white LEDs.

关键词： Barium tungstate microwave hydrothermal method spherical warm white lighting electron structures

Periodic Solutions for Two Coupled Nonlinear-Partial Differential Equations

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Communications in Theoretical Physics 2007年第3X期48卷 425-427页

作者： liu Shi-Da FU zun-Tao liu Shi-Kuo School of Physics Peking University Beijing 100871 China State Key Laboratory for Turbulence and Complex Systems Peking University Beijing 100871 China

In this paper, by applying the Jacobi elliptic function expansion method, the periodic solutions for two coupled nonlinear partial differential equations are obtained.

关键词： Jacobi elliptic function periodic wave solution nonlinear partial differential equation

The Two Main Mechanisms of Glacier Lake Outburst Flood in Tibet,China

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Journal of Mountain Science 2013年第2期10卷 239-248页

作者： liu Jing-jing TANG Chuan CHENG zun-lan Key Laboratory of Mountain Hazards and Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences State Key Laboratory of Geohazard Preventions Graduate School of Chinese Academy of Sciences

With the global warming,the disasters of Glacier Lake Outburst Flood(GLOF) have taken place frequently in Tibet in recent years and attracted more and more attention.A systematic survey was conducted on the 19 GLOFs in Tibet to study their two main *** indicated that all the events occurred in end-moraine lakes,and the outburst occurred partially and *** the breach had the shape of an arc or a trapezoid in overflow outburst and its top width was 3-5 times more than the *** two main mechanisms of GLOFs in Tibetan end-moraine Lake were overflow and piping,and the overflow mechanism caused by iceberg collapse was dominated in most cases.A formula was proposed to calculate the critical thickness of iceberg tongue that determines the *** analysis of the moraine materials revealed that seepage deformation is crucial in the outburst ***,we conducted a case study of the Guangxiecuo Lake to show its possible process of outburst and estimated the peak discharge of the resulted flood.

关键词： Glacier Lake Outburst Flood End-moraine Lake Outburst mechanism Overflow Piping Tibet