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2D-QSAR Studies on Triazolone Compounds Containing Benzenesulfonic Amide

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Chinese Journal of Structural Chemistry 2007年第8期26卷 883-888页

作者： WEI qing-li GAO jun SUN Dao-Xing ZHANG Shu-Sheng College of Chemistry and Molecular Engineering Qingdao University of Science ＆ Technology Qingdao 266042 China

The geometry structures of 6 triazolone compounds containing benzenesulfonic amide were fully optimized with DFT （Density Functional Theory） method at the B3LYP/6-31G level, and the structural and electronic parameters of the compounds were calculated. The hydrophobic and topological parameters of the title compounds were calculated by HyperChem software. The mono- and bi-parametric models between the parameters and biological activity of the compounds were analyzed by Multiple linear Regression method based on Hansch-Fujita model. The results show that the activities of the title compounds were increased with higher hydrophobic property logP and molecular volume V, lower molecular energy ETOTAL and electronegative of benzene ring Qph.

关键词： benzenesulfonic amide triazolone compounds 2D-QSAR DFT method

Applying systematic conservation planning to constitute a protection strategy for broad-leaved Korean pine forests in Changbai Mountains, China

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Journal of Mountain Science 2016年第3期13卷 493-507页

作者： MA lin SUN Gong-qi QU Yi li jun-qing Beijing university of civil engineering and architecture library Beijing 100044China Key Laboratory for Silviculture and Conservation of Ministry of Education Forest College Beijing Forestry University Beijing 100083 China Nature conservation College Beijing Forestry University Beijing 100083 China National and Local Joint Engineering Laboratory of Wetland and Ecological Conservation Heilongjiang Academy of sciences - Institute of Nature and Ecology Harbin 150040 China

The broad-leaved Korean pine(Pinus koraiensis) forest is one of the most biodiverse zonal communities in the North Temperate Zone and an important habitat for many endangered ***-leaved Korean pine forests(BKPFs) are shrinking quickly due to deforestation and rapid urbanization. Thus, scientific protection strategies are urgently needed to change this status. Changbai Mountains contains one of the largest BKPFs and is considered a priority biodiversity conservation area in China. Guided by systematic conservation planning(SCP) methods and procedures, we chose representative species and communities in BKPFs ecosystem as priority conservation objects, and set quantitative conservation target, which is in the light of the biodiversity characteristic of BKPFs. The watershed area is used as planning unit. We used CPlan software to calculate the irreplaceability(Ir)value of each planning unit and the contribution value(Ti) of each conservation object to(1) assess the conservation efficiency;(2) identify the conservation gap of the existing conservation network. Then wecalculated a human disturbance index(HDI) for planning units in the conservation gaps and combine this with the Ir value to design three conservation scenarios to optimize the conservation *** show that planning units with high conservation value 14.16% of the total area, with3084.36 km2 were covered by the existing conservation network. 79.28% of planning units with high conservation value have not been protected which were concentrated mainly in the eight gap *** 25.3% of protection objects achieved their conservation target with the existing conservation network. Conservation efficiency is low. Three conservation scenarios are constituted, each prioritizing a different aim:(1) ecological value;(2)species rescue; and(3) economical avoidance. The three conservation schemes potentially enable 93%,88% and 51% of conservation objects, respectively, to achieve identified conservatio

关键词： Korean Pine Changbai Mountain Systematic conservation planning Conservation network Protection strategy Conservation efficiency

Surface Second Harmonic Generation Circular Dichroism in Helix Molecular Films

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Chinese Physics Letters 2001年第3期18卷 382-384页

作者： XIN li li Chun-Fei li jun-qing ZHENG Yang-Dong Department of Physics Harbin Institute of TechnologyHarbin 150001

The formula for the intensity of surface second-harmonic generation circular dichroism(SHG-CD)in helical molecular films is *** influence of the pitch and radius of helical molecules on the surface SHG-CD intensity is numerically *** existence of a peak in curves of the surface SHG-CD intensity versus the pitch and radius is *** relation between the pitch and radius for different azimuthal angles is also discussed.

关键词： radius helical intensity

Improvement of a Fission-like Model for Nuclear α Decay

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Chinese Physics Letters 2010年第6期27卷 56-58页

作者： WANG Yong-Jia ZHANG Hong-Fei ZUO Wei li jun-qing School of Nuclear Science and Technology Lanzhou University Lanzhou 730000 Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000

Theα decay constant is the product of the penetrability P and assault frequency vo in the fission-like model. An effective assault frequency Pv replacing the previous assault frequency uo is introduced for improvement of a fission-like model named the generalized liquid drop model （GLDM） to describe the nuclear α decay process more accurately. Two analytical formulae are proposed for the effective assault frequency due to experimental data within the GLDM. The improved model can be used to give accurate calculations for α decay half-lives.

关键词： Biodeterioration Models

Microscopic Three-Body Force Effect on Nucleon-Nucleon Cross Sections in Symmetric Nuclear Matter

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Communications in Theoretical Physics 2008年第11期50卷 1219-1224页

作者： ZHANG Hong-Fei ZUO Wei Lombardo Umberto li Zeng-Hua li jun-qing School of Nuclear Science and Technology Lanzhou University Lanzhou 730000 China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou 730000 China Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China Dipartimento di Fisica Universitk di Catania and INFN-LNS Via S. Sofia 64 1-95123 Catania Italy

We provide a microscopic calculation of neutron-proton and proton-proton cross sections in symmetric nuclear matter at various densities, using the Brueckner Hartree-Fock approximation scheme with the Argonne Va4 potential including the contribution of microscopic three-body force. We investigate separately the effects of three-body force on the effective mass and on the scattering amplitude. In the present calculation, the rearrangement contribution of three-body force is considered, which will reduce the neutron and proton effective mass, and depress the amplitude of cross section. The effect of three body force is shown to be repulsive, especially in high densities and large momenta, which will suppress the cross section markedly.

关键词： nucleon-nucleon cross section nuclear matter three-body force

Quantitative measurement of the Exponential Growth of Spreading Width of a Quantum Wave Packet in Chaotic Systems

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Communications in Theoretical Physics 2002年第6期37卷 671-674页

作者： li jun-qing liu Fang Xing Yong-Zhong Zuo Wei Institute of Modern Physics Department of Physics Northwest University Xi'an 710069 China

The quantum correspondence of the very peculiar phenomenon of classical chaos-the exponential instability of motion can be characterized by the initially exponential growth rate of the total uncertainty measurement of the propagating quantum wave packet. Our calculation indicates that quantitatively the growth rate is approximately twice the classical maximum Lyapunov exponent of the system.

关键词：量子波包混沌系统波包宽度指数增长

Relativistic Mean Field Study of the Z -- 117 Isotopic Chain

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Chinese Physics Letters 2010年第6期27卷 52-55页

作者： GAO Yuan ZHANG Hong-Fei ZHANG Lei CHEN Xi-Meng li jun-qing GUO Wen-jun School of Information Engineering Hangzhou Dianzi University Hangzhou 310018 School of Nuclear Science and Technology Lanzhou University Lanzhou 730000 Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 College of Science University of Shanghai for Science and Technology Shanghai 200093

The properties of the Z = 117 isotopic chain are studied within the framework of the axially deformed relativistic mean field theory （RMFT） in the blocked BCS approximation. The ground-state properties, such as hinging energies, deformations as well as the possible α decay energies and lifetimes are calculated with the parameter set of NL-Z2 and compared with results from the finite range droplet model. The analysis by RMFT shows that the isotopes in the range of mass number A =291 ~ 300 exhibit higher stability, which suggests that they may be promising nuclei to be hopefully synthesized in the lab among the nuclei Z = 117.

关键词： RELATIVITY (Physics) MEAN field theory APPROXIMATION theory BINDING energy DEFORMATIONS (Mechanics) RADIOISOTOPES ATOMIC mass

Development of a texture evaluation system for winter jujube(Ziziphus jujuba‘Dongzao’)

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Journal of Integrative Agriculture 2022年第12期21卷 3658-3668页

作者： KONG Xia-bing XU Min WAN Hao-liang HAN ling-xi liU Xiao-li li qing-jun HAO Bian-qing ZHANG Shao-jun li Xiao-ming liU Yi-hui NIE Ji-yun College of Horticulture Qingdao Agricultural University/Laboratory of Quality&Safety Risk Assessment for Fruit(Qingdao)Ministry of Agriculture and Rural Affairs/National Technology Centre for Whole Process Quality Control of FSEN Horticultural Products(Qingdao)/Qingdao Key Lab of Modern Agriculture Quality and Safety EngineeringQingdao 266109P.R.China Management Service Center of Shandong Binzhou National Agricultural Science and Technology Park Binzhou 256600P.R.China Shanxi Center for Testing of Functional Agro-Products Shanxi Agricultural UniversityTaiyuan 030031P.R.China Institute of Biotechnology and Food Science Hebei Academy of Agriculture and Forestry SciencesShijiazhuang 050051P.R.China

Winter jujube(Ziziphus jujuba‘Dongzao’)is an excellent late maturing variety of fresh-eating jujube in *** texture is an important indicator of sensory *** investigate the correlations among texture indices and establish an evaluation system for winter jujube texture,we used the TMS-Touch instrument to perform a texture profile analysis(TPA)on 1150 winter jujubes from three major producing areas in *** indices and their best-fit distribution were obtained,including fracture(Pearson),hardness(InvGauss),adhesive force(Weibull),adhesiveness(LogLogistic),cohesiveness(LogLogistic),springiness(BetaGeneral),gumminess(InvGauss),and chewiness(InvGauss).Based on the best-fit distribution curves,each index was divided into five grades(lower,low,medium,high and higher)by the 10th,30th,70th and 90th *** the texture indices,82%of the correlation coefficients were highly significant(Plinear regression with the remaining four indices,with the coefficients above 0.94 and the mean fitting error and mean prediction error lower than 10%.A comprehensive evaluation model was consequently established based on factor analysis to evaluate the texture quality of winter *** results demonstrated that winter jujube with higher comprehensive scores generally exhibited higher springiness and chewiness,but had lower adhesive force and *** used factor analysis and clustering analysis to divide the eight studied texture into four groups(cohesive factor,adhesive-soft factor,tough-hard factor,and crispness factor),whose represe

关键词： winter jujube texture TPA evaluation representative indices

NONEQUIliBRIUM PROCESSES OF ANGULAR MOMENTUM DISSIPATION IN DEEPLY INELASTIC HEAVY-ION COLliSIONS

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Chinese Physics Letters 1985年第4期2卷 189-192页

作者： li jun-qing ZHU Jie-ding Institute of Modern Physics Academia SinicaLanzhou Department of Modern Physics Lanzhou UniversityLanzhou

The nonequilibrium processes of the angular momentum dissipation of fragments in deeply inelastic heavy-ion collisions have been investigated through consideration of the nondiagonal elements of the diffusion *** diff... 详细信息

关键词： tensor diffusion diagonal