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Sound Speed in a Shocked Tungsten Alloy: Its Significance in Studying “Softening” Mechanism to Multiphase Alloys

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Chinese Physics Letters 1996年第10期13卷 761-764页

作者： zhou Xian-ming jinG Fu-qian HU jin-biao Laboratory for Shock Wave and Detonation Physics Research Southwest Institute of Fluid PhysicsChengdu 610003

Optical analyzer technique are used to measure the sound speed as a function of pressure for shocked multiphase alloy 93 W containing 93%W, with 4.2%Ni-2.45%Fe-0.35%Co alloy as binder, all in wt.%. Below 250 GPa, the speed increases with pressure, then a bulk“softening” process occurs at 250 to 340 GPa, afterwards the speed again rises with pressure and coincides with the calculated bulk sound speed, showing a fluid-like behavior for this alloy. Lindemann melting law calculations were made for both the binder and the tungsten. The results showed that 250 GPa corresponds approximately to the pressure for the binder beginning to melt, and 340GPa corresponds to that for tungsten. Therefore, we believe that the shock-induced “softening” mechanism for this kind of multiphase alloys can be attributed to the binder melting.

关键词： softening alloy multiphase

Dynamics of two levitated nanospheres nonlinearly coupling with non-Markovian environment

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Chinese Physics B 2019年第5期28卷 32-37页

作者： Xun Li biao Xiong Shilei Chao Jiasen jin Ling zhou School of Physics Dalian University of Technology

The dynamics of two nanospheres nonlinearly coupling with non-Markovian reservoir is investigated. A master equation of the two nanospheres is derived by employing quantum state diffusion method. It is shown that the nonlinear coupling can improve the non-Markovianity. Due to the sharing of the common non-Markovian environment, the state transfer between the two nanospheres can be realized. The entanglement and the squeezing of the individual mode, as well as the jointed two-mode are analyzed. The present system can be realized by trapping two nanospheres in a wideband cavity, which might provide a method to study adjustable non-Markovian dynamics of mechanical motion.

关键词： non-Markovianity levitated nanospheres nonlinearity

Sensitivity function analysis of gravitational wave detection with single-laser and large-momentum-transfer atomic sensors

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Research in Astronomy and Astrophysics 2015年第3期15卷 333-347页

作者： biao Tang Bao-Cheng Zhang Lin zhou jin Wang Ming-Sheng Zhan State Key Laboratory of Magnetic Resonances and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences University of Chinese Academy of Sciences

Recently, a configuration using atomic interferometers （AIs） had been sug- gested for the detection of gravitational waves. A new AI with some additional laser pulses for implementing large momentum transfer was also put forward, in order to reduce the effect of shot noise and laser frequency noise. We use a sensitivity function to analyze all possible configurations of the new AI and to distinguish how many mo- menta are transferred in a specific configuration. By analyzing the new configuration, we further explore a detection scheme for gravitational waves, in particular, that ame- liorates laser frequency noise. We find that the amelioration occurs in such a scheme, but novelly, in some cases, the frequency noise can be canceled completely by using a proper data processing method.

关键词： gravitational wave detection -- atomic interferometer-- laser frequencynoise

Supercritical CO2 Assisted Preparation of Open-cell Foams of Linear Low-density Polyethylene and Linear Low-density Polyethylene/Carbon Nanotube Composites

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Chinese Journal of Polymer Science 2016年第7期34卷 889-900页

作者： jia wang 张利 jin-biao bao Ningbo Key Laboratory of Specialty Polymers Faculty of Materials Science and Chemical Engineering Ningbo University Ningbo 315211 China

The open-cell structure foams of linear low-density polyethylene（LLDPE） and linear low-density polyethylene（LLDPE）/multi-wall carbon nanotubes（MWCNTs） composites are prepared by using supercritical carbon dioxide（sc-CO2）as a foaming agent. The effects of processing parameters（foaming temperature, saturation pressure, and depressurization rate） and the addition of MWCNTs on the evolution of cell opening are studied systematically. For LLDPE foaming, the foaming temperature and saturation pressure are two key factors for preparing open-cell foams. An increase in temperature and pressure promotes both the cell wall thinning and cell rupture, because a high temperature results in a decrease in the viscosity of the polymer, and a high pressure leads to a larger amount of cell nucleation. Moreover, for the given temperature and pressure, the high pressurization rate results in a high pressure gradient, favoring cell rupture. For LLDPE/MWCNTs foaming, the addition of MWCNTs not only promotes the cell heterogeneous nucleation, but also prevents the cell collapse during cell opening, which is critical to achieve the open-cell structures with small cell size and high cell density.

关键词： Linear low-density polyethylene MWCNTs Supercritical carbon dioxide Foam Open-cell morphologies

Interaction of subway LIM vehicle with ballasted track in polygonal wheel wear development

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Acta Mechanica Sinica 2011年第2期27卷 297-307页

作者： Ling Li Xin-biao Xiao Xue-Song jin State Key Laboratory of Traction Power Southwest Jiaotong University 610031 Chengdu China

This paper develops a coupled dynamics model for a linear induction motor （LIM） vehicle and a subway track to investigate the influence of polygonal wheels of the vehicle on the dynamic behavior of the system. In the model, the vehicle is modeled as a multi-body system with 35 degrees of freedom. A Timoshenko beam is used to model the rails which are discretely supported by sleepers. The sleepers are modeled as rigid bodies with their vertical, lateral, and rolling motions being considered. In order to simulate the vehicle running along the track, a moving sleeper support model is introduced to simulate the excitation by the discrete sleeper supporters, in which the sleepers are assumed to move backward at a constant speed that is the same as the train speed. The Hertzian contact theory and the Shen– Hedrick–Elkins’ model are utilized to deal with the normal dynamic forces and the tangential forces between wheels and rails, respectively. In order to better characterize the linear metro system （LMS）, Euler beam theory based on modal superposition method is used to model LIM and RP. The vertical electric magnetic force and the lateral restoring force between the LIM and RP are also taken into consideration. The former has gap-varying nonlinear characteristics, whilst the latter is considered as a constant restoring force of 1 kN. The numerical analysis considers the effect of the excitation due to polygonal wheels on the dynamic behavior of the system at different wear stages, in which the used data regarding the polygonal wear on the wheel tread are directly measured at the subway site.

关键词： Linear induction motor Uneven wear Wheel out of roundness Vehicle-track coupling dynamics

Modified precoding strategy over MIMO double-correlated channels

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The Journal of China Universities of Posts and Telecommunications 2009年第2期16卷 35-38页

作者： jin Li-biao LI Jian-zeng School of Information Engineering Communication University of China Beijing 100024 China

Double-correlated channels commonly occur due to insufficient scattering around both the transmitting and receiving antennas. In this article, the authors propose a linear precoding strategy with a modified system model over double-correlated channels. In this system model, an inner decorrelation strategy is added combined with precoding. First, a linear precoder that achieves minimum bit error rate （MBER） is proposed and analyzed based on the modified system model. The simulation results show that the bit error rate （BER） performance can be improved by decorrelation. Second, the influence of double correlation on multiple input and multiple output （MIMO） capacity is analyzed and simulated.

关键词： MIMO precoding decorrelation capacity

Influence of crystal-transforming agent on the performance and mechanism ofα-high-strength gypsum prepared from FGD gypsum

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Particuology 2024年第4期87卷 37-45页

作者： Zhuoyue Xu Xiao Wang biao jin Dawang Zhang Hui Li College of Materials Science and Engineering Xi'an University of Architecture and TechnologyXi'an710055China Schoolof Materials and Chemical Engineering Henan University of Urban ConstructionPingdingshan46736China

This paper investigates the impact of flue gas desulfurization(FGD)gypsum's crystal modifier on the characteristics and microcosmic mechanism ofα-high strength *** results demonstrate that all three crystal modifiers can convert FGD gypsum toα-high-strength *** acid(CA)has the most significant influence onα-high-strength gypsum,and the preparedα-high-strength gypsum is short columnar,with an aspect ratio in the range of 1-3,and has a faster setting time,a larger specific surface area,and a smaller standard consistency,higher compressive strength,greater surface hardness,and smaller crystal particle *** initial setting time of theα-high-strength gypsum manufactured with CA crystal modifier was decreased by 36%compared to the blank sample,the final setting time was lowered by 37.5%,and the water consumption of the standard consistency was reduced by 8%.The maximum strength is 32 MPa after 2 h,the absolute dry compressive strength is up to 38 MPa,and the surface hardness is improved by 24.43%.

关键词： Flue gas desulfurization gypsum Crystal modifier Microscopic mechanism α-high-strength gypsum

Highly Oxygenated Dimeric Grayanane Diterpenoids as Analgesics:TRPV1 and TRPA1 Dual Antagonists from Rhododendron molle

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Chinese Journal of Chemistry 2022年第19期40卷 2285-2295页

作者： Lang Huang Guijuan Zheng Yuanyuan Feng Pengfei jin biao Gao Hanqi Zhang Xiaomin Ma Junfei zhou Guangmin Yao Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation School of PharmacyTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei430030 China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan650201 China Laboratory of Xinjiang Native Medicinal and Edible Plant Resource Chemistry College of Chemistry and Environmental ScienceKashi UniversityKashgarXinjiang844007 China

Six highly oxygenated dimeric grayanane diterpenoids(1—6)including three new ones,bismollethers A—C(1—3),were isolated from the flowers of Rhododendron molle collected at Qichun,Hubei,*** structures and relative configurations of 1—6 were determined by comprehensive spectroscopic data analysis and 13C NMR calculation with DP4+*** absolute configurations of bismollethers A—C(1—3)and birhodomollein B(5)were indubitably assigned by single-crystal X-ray diffraction analysis,revealing the head-to-tail linking manner of diterpenoid *** A(1)is a caged dimeric grayanane diterpenoid linked through two oxygen-bridges of C-2−O−C-14′and C-14−O−C-2′,featuring a unique 1,8-dioxacyclotetradecane *** plausible biosynthesis pathways of 1—6 are *** the isolates displayed significant analgesic activities and their structure-activity relationships were *** diterpenoid dimers were found to be TRPV1 and TRPA1 dual antagonists,and docking studies provide a structural basis to design potent analgesics.

关键词： Biological activity Dimeric grayanane diterpenoids Natural products Rhododendron molle(Ericaceae) Structure elucidation

Rational drug design, synthesis, and biological evaluation of novel chiral tetrahydronaphthalene-fused spirooxindole as MDM2-CDK4 dual inhibitor against glioblastoma

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Acta Pharmaceutica Sinica B 2020年第8期10卷 1492-1510页

作者： biao Wang Fu Peng Wei Huang jin zhou Nan Zhang Jia Sheng Phensinee Haruehanroengra Gu He Bo Han Hospital of Chengdu University of Traditional Chinese Medicine State Key Laboratory of Southwestern Chinese Medicine ResourcesSchool of PharmacyChengdu University of Traditional Chinese MedicineChengdu 611137China State Key Laboratory of Biotherapy and Cancer Center West China HospitalSichuan University and Collaborative Innovation Center for BiotherapyChengdu 610041China Department of Chemistry and the RNA Institute University at AlbanyState University of New YorkAlbanyNY 12222USA

Simultaneous inhibition of MDM2 and CDK4 may be an effective treatment against glioblastoma. A collection of chiral spirocyclic tetrahydronaphthalene(THN)-oxindole hybrids for this purpose have been developed. Appropriate stereochemistry in THN-fused spirooxindole compounds is key to their inhibitory activity: selectivity differed by over 40-fold between the least and most potent stereoisomers in time-resolved FRET and KINOMEscan~? in vitro assays. Studies in glioblastoma cell lines showed that the most active compound ent-4g induced apoptosis and cell cycle arrest by interfering with MDM2-P53 interaction and CDK4 activation. Cells treated with ent-4g showed up-regulation of proteins involved in P53 and cell cycle pathways. The compound showed good anti-tumor efficacy against glioblastoma xenografts in mice. These results suggested that rational design, asymmetric synthesis and biological evaluation of novel tetrahydronaphthalene fused spirooxindoles could generate promising MDM2-CDK4 dual inhibitors in glioblastoma therapy.

关键词： MDM2 glioblastoma CDK4