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Syntheses, Structures and Magnetic Properties of Two Coordination Polymers Based on 2,2-Biphenyldicarboxylate Ligand

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Chemical Research in Chinese Universities 2016年第2期32卷 165-171页

作者： ZHANG Qingfen ZHOU Zhongyuan WANG Xuan lu jing Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology School of Chemistry and Chemical Engineering Liaocheng University Liaocheng 252059 P R. China

Two coordination polymers {[Co3L3（Me2NH）2]·（Me2NH）}n（1） and [CuL（bpy）],（2）（L=2,2＇-biphenyl dicarboxylate ion, bpy=4,4＇-bipyridine） were obtained and characterized. Compound 1 was synthesised via solvotherreal method, with the L ligands adopting syn-syn-μ2-η1：η1- and μ2-η2-coordination modes and Co（II） centers being linked to form a 1D coordination chain with trinuclear Co3 cluster as sub-units. Compound 2 was synthesized at room temperature, with the L ligand chelating the Cu（II） centers to form a 1D chain, which was further linked by the auxiliary 4,4＇-bpy ligand to form a 3D coordination network. The results of variable temperature susceptibility studies reveal that there were ferromagnetic and antiferromagnetic interactions between the paramagnetic metal centers in compounds 1 and 2, respectively.

关键词： Coordination polymer Crystal structure Magnetic property

APPLICATION OF QUADRATIC AND CUBIC TURBULENCE MODELS ON CAVITATING FLOWS AROUND SUBMERGED OBJECTS

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Journal of Hydrodynamics 2012年第6期24卷 823-833页

作者： CHEN Ying lu Chuan-jing CAO Jia-yi CHEN Xin Department of Engineering Mechanics Shanghai Jiao Tong University Department of Engineering Mechanics and State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University

Quadratic and cubic Non-Linear Eddy-Viscosity Models （NLEVMs） at low Reynolds number （Re） correction were introduced into the present Computational Fluid Dynamics （CFD） framework, to provide better numerical treatment about the anisotropic turbulence stress in cavitating flows, which have large density ratio and large-scaled swirling flow structures. The applications of these NLEVMs were carried out through a self-developed cavitation code, coupled with a cavitation model based on the transport equation of liquid phase. These NLEVMs were firstly validated by the benchmark of disk supercavity, and found able to obtain more accurate capture of the hydrodynamic properties than the linear models. One of such models was further applied on the cavitation problem of submerged vehicles. Ultimately, the supercavitating flows around an especially designed underwater vehicle were predicted using the cubic k - e turbulence model, and its cavitation behaviors were studied.

关键词： cavitating flow Non-Linear Eddy-Viscosity Model (NLEVM) submerged object cavitation model

NUMERICAL SIMULATIONS OF 2D PERIODIC UNSTEADY CAVITATING FLOWS

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Journal of Hydrodynamics 2006年第3期18卷 341-344页

作者： WU Lei lu Chuan-jing LI Jie CHEN Xin Department of Engineering Mechanics Shanghai Jiaotong University Shanghai 200240 China

A two-phase mixture model was established to study unsteady cavitating flows. A local compressible system of equations was derived by introducing a density-pressure function to account for the two-phase flow of water/vapor and the transition from one phase to the other. An algorithm for solving the variable-density Navier-Stokes equations of cavitating flow problem was put forward. The numerical results for unsteady characteristics of cavitating flows on a 2D NACA hydrofoil coincide well with experimental data.

关键词： unsteady cavitating flow variable-density Navier-Stokes equations periodic cavity break-off and shedding hydrofoil

Complementarity via Minimum Error Measurement in a Two-Path Interferometer

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Chinese Physics Letters 2019年第5期36卷 12-16页

作者： Junzhao Liu Yanjun Liu jing lu Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Department of Physics and Synergetic Innovation Center of Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081

We study the fringe visibility and the which-path information(WPI) of a general Mach-Zehnder interferometer with an asymmetric beam splitter(BS). A minimum error measurement in the detector is used to extract the WPI. Both the fringe visibility V and the WPI I_(path) are affected by the initial state of the photon and the second asymmetric BS. The condition in which the WPI takes the maximum is obtained. The complementarity relationship V^2 + I_(path)~2 ≤ 1 is found, and the conditions for equality are also presented.

关键词： WPI Complementarity via Minimum Error Measurement in a Two-Path Interferometer MZI

Geomorphological-geological-geophysical signatures of high-flux fluid flows in the eastern Pearl River Mouth Basin and effects on gas hydrate accumulation

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Science China Earth Sciences 2018年第7期61卷 914-924页

作者： Zenggui KUANG Yunxin FANG Jinqiang LIANG jing'an lu Lei WANG Key Laboratory of Marine Mineral Resources Ministry of Land and ResourcesGuangzhou Marine Geological Survey New Energy Project Department China National Petroleum Corporation Offshore Engineering Company Limited

Marine hydrate reservoirs can be divided into focused high-flux and distributed low-flux gas hydrate systems according to free gas migration control mechanisms. In focused high-flux hydrate reservoirs, fluids easily break through the pressure of overlying sediments and reach the shallows, creating a series of geomorphological-geological-geophysical anomalies at and near the seafloor. Based on detailed interpretation of pre-drilling data in the eastern Pearl River Mouth Basin(PRMB),many anomalies related to the high-flux fluid flow are found, including seafloor mounds with intrusive characteristics, bright spot reflections above the bottom-stimulating reflector(BSR), phase reversals in the superficial layer, and an efficient fluid migration and accumulation system composed of fractures and uplifts. The second hydrate drilling expedition was carried out in the eastern PRMB in 2013 to study these anomalies. The acquired data show that high-flux fluid flow occurred in these sites. Gas hydrate pingoes, bright spot reflection above the BSR, and an efficient fluid migration and accumulation system can be used as identification signatures for high-flux fluid migration. The modes of high flux fluid flow are different in deep and shallow sediments during upward migration of fluid. Gas dissolved within migrating water dominates deep fluid migration and upward migration of a separate gas phase dominates the shallow process. This difference in migration models leads to formation of upper and lower concentrated hydrate reservoirs in the drilling area. The discovery of signatures of high-flux fluid flow and their migration modes will help with site selection and reduce risk in gas hydrate drilling.

关键词： Eastern Pearl River Mouth Basin Gas hydrate High-flux fluid flow Geomorphological-geological-geophysicalsignatures

Screening for a new Streptomyces strain capable of efficient keratin degradation

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Journal of Environmental Sciences 2007年第9期19卷 1125-1128页

作者： CHAO Ya-peng XIE Fu-hong YANG jing lu jing-hua QIAN Shi-jun State Key Laboratories of Transducer Technology Institute of Microbiology Chinese Academy of Sciences Beijing 100080 China.

Keratinous wastes could be degraded by some microorganisms in nature. Native human foot skin （NHFS） was used as sole nitrogen source to screen microorganisms with keratin-degrading capability. From approximately 200 strains, a strain of Streptomyces sp. strain No. 16 was found to possess the strongest keratinolytic activity, and the total activity in the culture was 110 KU/ml with specific activity of 2870 KU/mg protein （KU： keratinase unit）. Substrate specificity test indicated that the crude keratinase could degrade keratin azure, human hair, cock feathers and collagen. The optimal pH of the crude keratinase ranged from 7.5 to 10 and the temperature ranged from 40℃ to 55℃. Metal chelating agent ethylenediamine tetraacetic acid obviously stimulated the keratinolytic activity but suppressed the proteolytic activity. To our knowledge, this is the first report on specific induction of keratinases by NHFS from an actinomycete. Moreover, excellent characteristics of its crude keratinase may lead to the potential application in waste treatment and recovery, poultry and leather industry, medicine, and cosmetic development.

关键词： keratinolytic capability Streptomyces sp. native human foot skin (NHFS) keratinase substrate specificity

Spontaneous emission of a moving atom in a waveguide of rectangular cross section

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Chinese Physics B 2023年第2期32卷 92-96页

作者：曾静卢竞周兰 Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Department of Physics and Synergetic Innovation Center of Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China

We study the spontaneous emission(SE) of an excited nonrelativistic two-level system(TLS) interacting with the vacuum in a waveguide of rectangular cross section. All TLS’s transitions and the center-of-mass motion of the TLS are taken into account. The SE rate and the carried frequency of the emitted photon for the TLS initially being at rest are obtained, it is found that in the first order of the mass M, the frequency of the emitted photon is smaller than the transition frequency of the TLS and the SE rate is smaller than the SE rate Γfof the TLS fixed in the same waveguide. The SE rate for the TLS initially being moving is obtained in the second order of the mass M. The SE rate is smaller than Γfbut it is dependent not only on the atomic mass but also on the initial momentum. The carried frequency of the emitted photon is decreased when it travels along the direction of the initial momentum, whereas it is increased when it travels in the opposite direction of the initial momentum.

关键词： spontaneous emission moving atom waveguide of rectangular cross section

Potential oscillations across oil-water interface in the presence of the biological surfactant and amino acids or polypeptides

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Chinese Science Bulletin 1998年第12期43卷 1008-1011页

作者： Li Hexing Li Penghong lu jing Shanghai Normal Univ Dept Chem Shanghai 200234 Peoples R China Fudan Univ Dept Chem Shanghai 200433 Peoples R China

A lot of potential oscillations across oil_water interface ahve been designed by using various surfactants and biological surfactants in the aqueous phase and various amino acids or even polypeptides in the oil phase (nitrobenzene solution). Effects of the reactant’s concentration and the reaction temperature on the oscillating parameters have been studied. The oscillating mechanism has been discussed, and a model fo the oscillating mechanism has been proposed which is proved qualitatively reasonable according to the simulation.

关键词： oscillations at liquid membrane amino acid polypeptide surfactant.

Influence of mountain-valley morphology on in-situ stress distribution

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Journal of Mountain Science 2021年第9期18卷 2447-2459页

作者： ZHANG Chuan-qing CUI Guo-jian ZHOU Hui YANG Fan-jie lu jing-jing State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China

The in-situ stress field is a key factor controlling the successful construction of a large number of underground structures in mountainous areas,and is intensively affected by the mountainvalley *** effects of mountain-valley morphology(the width of the mountain top platform,mountain height,slope angle,and width of the valley bottom)on the distribution of the in-situ stress field were analyzed and interpreted using numerical modeling techniques,where the spatial distribution and maximum values of the horizontal and vertical stresses were *** results showed that there existed a critical value of the topographic influence depth,where the in-situ stress distribution varied significantly as mountain-valley morphology,after which the influence *** action has a more remarkable influence on the in-situ stress distribution than gravitational action under the same mountain-valley ***,the relationships between the magnitudes of these stress components and the morphology variables are described using empirical formulas,which can be directly applied to different topographies to rapidly achieve a rational *** findings of this study can be very useful for quickly understanding the in-situ stress distribution and as stress measurement guidelines.

关键词： In-situ stress Mountain-valley morphology Gravitational action Tectonic action