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Escape of Brownian Particles in the System Driven by Correlated White Noises:Comparison of Three Models

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Communications in Theoretical Physics 2001年第11期36卷 535-540页

作者： YOU jing-Yun CAO li WU Da-jin zhang li State Key Laboratory for Laser Technology Huazhong University of Science and TechnologyWuhan 430074China Department of Physics Huazhong University of Science and TechnologyWuhan 430074China State Key Laboratory for Laser TechnologyHuazhong University of Science and TechnologyWuhan 430074China CCAST (World Laboratory) P.O.Box 8730Beijing 100080China CCAST (World Laboratory)P.O.Box 8730Beijing 100080China Department of PhysicsHuazhong University of Science and TechnologyWuhan 430074China

The relative escape rate (RER) in the bistable sawtooth system driven by correlated white noises was studied in the case of linear multiplicative noise *** we compare the RER of linear multiplicative noise coefficient with the RER of the piecewise constant multiplicative noise coefficient in the bistable sawtooth system,finally compare the RER of the bistable sawtooth potential with the RER of the quartic potential in the case of linear multiplicative noise *** can be seen that the form of the multiplicative noise coefficient and the nonlinearity of potential have an important influence on the resonant activation and the suppression of the *** resonant activation of the RER vanishes in the negative correlation when the multiplicative noise coefficient was shifted from piecewise constant to linear function in the bistable sawtooth *** suppression of the RER disappears in the negative correlation when thelinear potential is converted into nonlinear one.

关键词： the correlated noises,escape rate,resonant activation,suppression

On the horizon of Protopteryx and the early vertebrate fossil assemblages of the Jehol Biota

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Chinese Science Bulletin 2008年第18期53卷 2820-2827页

作者： jin Fan zhang FuCheng li ZhiHeng zhang JiangYong li Chun ZHOU ZhongHe Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China

Protopteryx, a monotypic fossil bird discovered from the Sichakou basin in Fengning, Hebei, is the most primitive enantiornithine currently known. The bird-bearing strata do not contain the index fossils of the Yixian Formation in western liaoning; the fish and bird fossils have more primitive features than the related forms found in the Yixian Formation, and the conchostracans are those usually distributed in the Dabeigou and Dadianzi formations in northern Hebei. Besides, the Protopteryx-bearing strata underlie the deposits bearing the index fossils of the Yixian Formation in the neighboring basin. Thus, it could be confirmed that the horizon of Protopteryx should be lower than the Yixian Formation, and is approximately equivalent to the Dadianzi Formation in northern Hebei. This is the lowest horizon of the known fossil birds in China and Mesozoic enantiornithine birds in the world. Accompanying Protop- teryx, there are other birds, acipenseriform fishes, salamanders, and mammals, which compose the Peipiaosteus fengningensis-Protopteryx fengningensis assemblage. This new assemblage traces the vertebrate evolution history of the Jehol Biota back to 130.7 Ma before. It is suggested that the de- marcation of the Jehol Biota should be based on the large-scale tectonic-sedimentary cycles, and Peipiaosteus, instead of Lycoptera, could be taken as the vertebrate representative of the Jehol Biota.

关键词：脊椎动物化石地层古生物学研究方法

The Herbicidal Activity of Mutant Isolates from Botrytis cinerea

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Agricultural Sciences in China 2006年第8期5卷 622-628页

作者： zhang jin-lin zhang li-hui liU Ying-chao MA Juan li Chuan DONG jin-gao Mycotoxin Laboratory Hebei Agricultural University Baoding 071001 P.R.China

Fifteen mutant isolates were obtained by ultraviolet mutation from parent isolate Botrytis cinerea BC-4. Among them three mutant isolates, BC4-1, BC4-2, and BC4-15, showed strong herbicidal activity. BC4-1 showed maximum herbicidal activity for inhibition of germination and growth of Digitaria sanguinalis L. and Arnaranthus retroflexus L. The results also showed that herbicidal activity was influenced by differing pH of PD media, with pH value of 4.0 being the optimum. The crude toxin was extracted using chloroform, petroleum ether, and ethyl acetate, respectively, and the ethyl acetate extracts showed the strongest inhibitory activity on the germination and growth of D. sanguinalis L. and A. retroflexus L. Using HPLC, one fraction with an absorption peak at 271 nm was separated from the crude toxin. This fraction could strongly inhibit the growth of D. sanguinalis L. at a concentration of 100 mg L^-1 and could completely inhibit the seed germination of D. sanguinalis L. and A. retroflexus L. at a concentration of 50 mg L^-1 .

关键词： Botrytis cinerea toxin ultraviolet mutation herbicide activity separation and purification

Discussion of thermodynamic features within the PNJL model

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Chinese Physics C 2018年第12期42卷 32-43页

作者： jin-li zhang Cheng-Ming li Hong-Shi Zong Department of Physics Nanjing UniversityNanjing 210093China Joint Center for Particle Nuclear Physics and CosmologyNanjing 210093China 2.State Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsCASBeijing 100190China

We discuss some thermodynamical features of a QCD system within the two-flavor Polyakov loop ex- tended Nambu Jona-Lasinio （PNJL） model. Several thermodynamical quantities of interest （pressure, energy density, specific heat, speed of sound, etc.） are investigated and discussed in detail with two different forms of Polyakov loop potential. The effective coupling strength G incorporating a quark feedback （quark condensate） through operator product expansion is also discussed, as well as the relationship between color deconfinement and chiral phase crossover. We find that some thermodynamical quantities have quite different behavior for different Polyakov loop potentials. By changing the characteristic temperature To of the pure Yang-Mills feld, we find that when To becomes small, color deconfinement might happen earlier than chiral phase crossover, while their relationship can be determined via some thermodynamical quantities. Furthermore, the behavior of the thermodynamical quantities is quite different in the two different forms of Polyakov loop potential studied. Especially, one of the potentials, specific heat, has two peaks, which correspond to color deconfinement and chiral phase crossover respectively. This interesting phenomenon may shed some light on whether the inflection points at the same temperature or not for lattice QCD and of the chiral condensate and deconfinement transitions happen experimental studies.

关键词： deconfinement specific heat transition temperature

Eu(Ⅲ) complex-doped PMMA having fast radiation rate and high emission quantum efficiency

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Chinese Chemical Letters 2012年第8期23卷 945-948页

作者： jin li zhang Bo Wei Chen Xuan Luo Kai Du Research Center of Laser Fusion China Academy of Engineering PhysicsMianyang 621900China School of Physics and Electronic Engineering Mianyang Normal UniversityMianyang 621000China

Three Eu（III） ternary complexes, Eu（hfa-H）3（Phen）, Eu（hfa-H）3（Bipy） and Eu（hfa-H）3（Bath）（hfa = hexafluoroacetylacetonate, Phen = 1,10-phenanthroline, Bipy = 2,2＇-bipyridine, Bath = bathophenanthroline）, were synthesized. Their luminescent properties were studied by incorporating deuterated Eu（III） complexes in a poly（methylmethacrylate）（PMMA） matrix, and the results indicated that luminescent PMMA including Eu（hfa-D）3（Bath） showed promising results for applications to novel organic Eu（III） devices, such as the high-power laser materials. Additionally, all the three Eu（III） complexes exhibited good thermostabilization.

关键词： Photolunainescence Eu(III) complex Rare earths

Eu(Ⅲ) Complex-doped PMMA with Fast Radiation Rate and High Emission Quantum Efficiency

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Chemical Research in Chinese Universities 2012年第6期28卷 1054-1057页

作者： zhang jin-li CHEN Bo-wei LUO Xuan DU Kai Research Center of Laser Fusion China Academy of Engineering Physics Mianyang 621900 P. R. China School of Physics and Electronic Engineering Mianyang Normal University Mianyang 621000 P. R. China

Two Eu（Ⅲ） complexes,（tris-4,4,4-trifluoro-1-phenyl-1,3-butanedione）（1,10-phenanthroline）europium（Ⅲ） [Eu（tpb-H） 3（phen）] and（tris-4,4,4-trifluoro-1-phenyl-1,3-butanedione）（2,2＇-bipyridine）europium（Ⅲ）[Eu（tpb-H） 3（bipy）] were synthesized from bi-dental oxygen and nitrogen *** polymers were fabricated by incorporating deuterated Eu（Ⅲ） complexes in poly（methylmethacrylate）（PMMA） *** PMMA containing Eu（tpb-D） 3（phen） exhibited relatively higher quantum yield[Φ,（48.7±4）%],faster radiation rate（k r,7.49×10 2 s-1）,sharper red emission[full width at half maximum（FWHM）,6.3 nm] and larger stimulated emission cross-section（SEC,1.29×10-20 cm 2）.The value of SEC is the same order as that of Nd-glass laser for practical ***,the thermal properties of Eu（tpb-H） 3（phen）,Eu（tpb-H） 3（bipy）,Eu（tpb-D） 3（phen）-PMMA,and Eu（tpb-H） 3（bipy）PMMA were studied,indicating that the Eu（Ⅲ） complexes and luminescent PMMA can be used for a long-term period in high temperature *** luminescent polymers including Eu（tpb-D） 3（phen） have promising applications in novel organic Eu（Ⅲ） devices,such as the high-power laser materials and optical fibers.

关键词： Photophysics Fluorescence Rare earth

Meta-analysis of brain activation in depressive patients with emotional perception disorders

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Neural Regeneration Research 2011年第31期6卷 2429-2434页

作者： Chenwang jin Ming zhang Dan li Shaohui Ma Yuan Wang Min li lihua liu Medical Imaging Center First Hospital of Xi＇an Jiaotong University Xi＇an 710061 Shaanxi Province China

OBJECTIVE：To elucidate the distribution of abnormally activated brain regions in depressive patients during emotional perception processing using activation likelihood estimation,a quantitative meta-analytic *** SOURCES：Computer-based online retrieval was conducted using the PscyINFO,Pubmed and CNKI databases,searching literature from the establishment of each database until June *** SELECTION：Inclusion criteria：（1） studies examined emotion perception tasks using func-tional magnetic resonance imaging; （2） studies indicated regional brain activation abnormalities in depressive patients compared with controls in standard Talairach or MNI *** analyzed coordinates based on the MNI system were converted to Talairach space with icbm2tal *** map of activation likelihood estimation was finally created through the Gaussian smooth （full-width half-maximum=8 mm）,permutation test and corrected for multiple comparisons using the false discovery rate method （q=0.05） with Ginger-ALE 2.0 *** OUTCOME MEASURES：Activation of brain regions in ***：Seventeen studies were identified,involving a total of 261 patients,273 healthy controls and 201 ***-analysis revealed a dysfunctional emotion regulation loop in depressive patients,comprised of the prefrontal cortex,the basal ganglia and the limbic lobe,in which the amygdala was a key *** emotion processing,the left prefrontal cortex and basal ganglia were hy-poactive among depressive patients,whereas the opposite change was found in the limbic ***：Abnormal connections among the prefrontal cortex,basal ganglia and limbic lobe may be involved in the pathophysiology of depressive disorder.

关键词： depression functional magnetic resonance imaging emotional perception disorder prefrontal cortex basal ganglia limbic lobe meta-analysis

Effects of physical properties of supercritical water on heat transfer characteristics of single particle within a particle cluster Author links open overlay panel

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Particuology 2024年第8期91卷 291-302页

作者： Xiaoyu li Bowei zhang Huibo Wang Hui jin State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an710049China

The complex physical properties of supercritical water(SCW)make the heat transfer characteristics of particles within a particle cluster *** heat transfer characteristics of single particle within a particle cluster in SCW,influenced by surrounding particles,have not been effectively *** numerical simulations were conducted to investigate the heat transfer characteristics of particle clusters in SCW under different *** results were compared and analyzed with those from constant property *** was found that Reynolds number(Re)and the void fraction of particle cluster have no special effects on the variation trends of Nusselt number(Nu)for the focused ***,the particle temperature had a significant effect on the variation trends of *** effect of Re on the heat transfer rate exponent(η)of the focused particle can be divided into two zones:a significant effect zone and a non-significant effect *** effect of void fraction onηin the non-significant effect zone was *** the non-significant effect zone,ηdecreased with the increasing particle *** the significant effect zone,the variation trends ofηbecame more *** fundamental reason for this series of phenomena is the changes in distribution of physical properties.A model forηwas developed for the non-significant effect *** model can filter out the effects of Re and certain particle cluster spatial configurations,and it demonstrates good predictive performance.

关键词： Supercritical water Particle cluster Heat transfer characteristics Heat transfer rate exponent Physical properties correction

Fast solution to the free return orbit's reachable domain of the manned lunar mission by deep neural network

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Journal of Systems Engineering and Electronics 2024年第2期35卷 495-508页

作者： YANG Luyi li Haiyang zhang jin ZHU Yuehe College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China China Astronauts Research and Training Center Beijing 100094China Hunan Key Laboratory of Intelligent Planning and Simulation for Aerospace Missions Changsha 410073China

It is important to calculate the reachable domain(RD)of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly evaluated and calculated via the classification and regression neural networks. An efficient databasegeneration method is developed for obtaining eight types of free return orbits and then the RD is defined by the orbit’s inclination and right ascension of ascending node(RAAN) at the perilune. A classify neural network and a regression network are trained respectively. The former is built for classifying the type of the RD, and the latter is built for calculating the inclination and RAAN of the RD. The simulation results show that two neural networks are well trained. The classification model has an accuracy of more than 99% and the mean square error of the regression model is less than 0.01°on the test set. Moreover, a serial strategy is proposed to combine the two surrogate models and a recognition tool is built to evaluate whether a lunar site could be reached. The proposed deep learning method shows the superiority in computation efficiency compared with the traditional double two-body model.

关键词： manned lunar mission free return orbit reachable domain(RD) deep neural network computation efficiency