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Journal of Advanced ceramics 2021年第3期10卷 578-586页

作者： lin-Kun SHI Xiaobing ZHOU Jian-qing DAI Ke cHEN Zhengren HUANG qing HUANG Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China Engineering laboratory of Advanced Energy Materials Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China

A nano-laminated Y_(3)Si_(2)c_(2) ceramic material was successfully synthesized via an in situ reaction between YH_(2)and Sic using spark plasma sintering technology.A MAX phase-like ternary layered structure of Y_(3)Si_(2)c_(2) was observed at the atomic-scale by high resolution transmission electron *** lattice parameters calculated from both X-ray diffraction and selected area electron diffraction patterns are in good agreement with the reported theoretical *** nano-laminated fracture of kink boundaries,delamination,and slipping were observed at the tip of the Vickers *** elastic modulus and Vickers hardness of Y_(3)Si_(2)c_(2) ceramics(with 5.5 wt%Y_(2)O_(3)) sintered at 1500℃were 156 and 6.4 GPa,*** corresponding values of thermal and electrical conductivity were 13.7 W·m^(-1)·K^(-1) and 6.3×10^(5)S·m^(-1),respectively.

关键词： Y3Si_(2)c_(2) rare earth silicide carbides spark plasma sintering(SPS) ternary layered structure ceramic properties

Description of N=7～9 Isotones with a Modified Single-Particle Potential

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communications in Theoretical Physics 2008年第12期50卷 1396-1400页

作者： GUO Yan-qing REN Zhong-Zhou cHEN Yu-qing Department of Physics Nanjing University Nanjing 210008 China center of Theoretical Nuclear Physics National Laboratory of Heavy-Ion Accelerator Lanzhou 730000 China Joint center for Particle Nuclear Physics and Cosmology Nanjing 210008 China Department of Physics and Electronic Engineering Hanshan Normal University Chaozhou 521041 China

We study the level structures of N = 7 - 9 isotones and their mirror nuclei in the framework of the single-particle potential model. considering the limitation of the conventional potential-model calculation, the isospindependent 12 coupling is newly introduced in the average potential. The modified model gives a unified description for the structures of all studied nuclei. Galculations self-consistently produce the s-d level inversion in N = 9 isotones and their mirror nuclei. Meanwhile, the s-p level inversion in the mirror nuclei ^11Be and ^11N is reproduced. The study confirms the neutron halo structures in ^11Be（2s1/2）, ^11Be（1p1/2）, ^12B（2s1/2）, ^14B（2s1/2）, ^13c（2sl/2）, ^15c（2s1/2） and the proton halo structure in ^17F（2s1/2）. The agreement between theory and experiment indicates that the inclusion of the i2 coupling is a feasible way to explain the abnormal structures of exotic light nuclei.

关键词： modified single-particle potential level inversion l^2 coupling

Effect of methyl tert-butyl ether on adipogenesis and glucose metabolism in vitro and in vivo

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Journal of Environmental Sciences 2019年第11期31卷 208-219页

作者： Yue Tang Qidong Ren qing Wen caixia Yu Xinni Xie qing Hu Yuguo Du State Key laboratory of Environmental chemistry and Eco-toxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China School of chemical Sciences University of Chinese Academy of Sciences Beijing 100049 China School of Environmental Science and Engineering Southern University of Science and Technology Shenzhen 518055 China

Methyl tert-butyl ether (MTBE),as a widely used gasoline additive,is suspected of being environmentally *** accumulates mainly in adipose tissue,but its effect on obesity or obesity-related metabolic disorders has not been well understood ***,we examined the effect of MTBE on the adipose function and the related metabolic processes with both 3T3-l1 cell line and c57Bl/6J mice *** found that exposure to MTBE at the environmental relevant concentration (100 μmol/l) could significantly induce differentiation of preadipocyte and disturb insulin-stimulated glucose uptake of mature *** in vivo observation in male mice showed a positive correlation of visceral white adipose tissue (vWAT) expansion and cell size increase with MTBE treatment in 14 *** tolerance and insulin sensitivity tests demonstrated that MTBE at 1000 μg/(kg·day) disturbed the systemic glucose metabolism in a gender-specific manner,which might be partly attributed to the alterations of gut microbiota community at genus level with respect to Akkermansia,clostridium XIVb,and *** summary,our study characterized the effect of MTBE on adipose tissue function and glucose homeostasis in vitro and in vivo,and revealed that systemic disorders of the glucose metabolism might be modulated by the related gut microbiota.

关键词： MTBE Adipogenesis Glucose metabolism Metabolic disorder Gut microbiota

Transgenic Brassica chinensis plants expressing a bacterial codA gene exhibit enhanced tolerance to extreme temperature and high salinity

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第11期11卷 851-861页

作者： qing-bin WANG Wen XU qing-zhong XUE Wei-ai SU Department of Agronomy College of Agriculture and Biotechnology Zhejiang University Hangzhou 310029 China Shanghai Institute of Plant Physiology and Ecology Chinese Academy of Science Shanghai 200032 China School of Resource and Environment Management Guizhou College of Finance and Economics Guiyang 550004 China

Transgenic Brassica compestris *** plants expressing a choline oxidase(codA) gene from Arthrobacter globiformis were obtained through Agrobacterium tumefaciens-mediated *** the transgenic plants,codA gene expression and its product transportation to chloroplasts were detected by the enzyme-linked immunosorbent assay(ElISA) examination,immunogold localization,and 1 H-nuclear magnetic resonance( 1 H-NMR) . Stress tolerance was evaluated in the T3 plants under extreme temperature and salinity *** plants of transgenic line 1(l1) showed significantly higher net photosynthetic rate(Pn) and Pn recovery rate under high(45°c,4 h) and low temperature(1°c,48 h) treatments,and higher photosynthetic rate under high salinity conditions(100,200,and 300 mmol/l Nacl,respectively) than the wild-type *** enhanced tolerance to high temperature and high salinity stresses in transgenic plants is associated with the accumulation of betaine,which is not found in the wild-type *** results indicate that the introduction of codA gene from Arthrobacter globiformis into Brassica compestris *** could be a potential strategy for improving the plant tolerance to multiple stresses.

关键词： Brassica compestris l. spp. chinensis codA Stress Glycine betaine Net photosynthetic rate (Pn)

Reducible solution to a quaternion tensor equation

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Frontiers of Mathematics in china 2020年第5期15卷 1047-1070页

作者： Mengyan XIE qing-Wen WANG Department of Mathematics Shanghai UniversityShanghai 200444China

We establish necessary and sufficient conditions for the existence of the reducible solution to the quaternion tensor equation A*N c*NB=c via Einstein product using Moore-Penrose inverse,and present an expression of the reducible solution to the equation when it is ***,to have a general solution,we give the solvability conditions for the quaternion tensor equation A1*N c1*MB1+a1*c2*MB2+A2*Nc3*MB2=e,which plays a key role in investigating the reducible solution to A*Nc*NB=*** expression of such a solution is also presented when the consistency conditions are *** addition,we show a numerical example to illustrate this result.

关键词： Quaternion tensor quaternion tensor equation Einstein product Moore-Penrose inverse general solution reducible solution

long range electromagnetic field nature of nerve signal propagation in myelinated axons

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chinese Physics B 2022年第3期31卷 619-623页

作者： qing-Wei Zhai Kelvin J A Ooi Sheng-Yong Xu c K Ong School of Electrical and computer Engineering Xiamen University MalaysiaSelangor Darul Ehsan 43900Malaysia Department of Physics Xiamen University MalaysiaSelangor Darul Ehsan 43900Malaysia Department of Electronics School of Electronics Engineering and Computer SciencePeking UniversiyBeijing 100871China Department of Physics National University of Singapore2 Science Drive 3117551 Singapore

The nature of saltatory conduction in myelinated axon described by equivalent circuit and circuit theory is still contentious. Recent experimental observations of action potentials transmitting through disjointed nerve fibers strongly suggest an electromagnetic wave propagation mechanism of the nerve signals. In this paper, we employ the electromagnetic wave model of the myelinated axon to describe action potential signal propagation. We use the experimental frequency-dependent conductivity and permittivity values of the nerve tissues in order to reliably calculate the electromagnetic modes by using electromagnetic mode solvers. We find that the electromagnetic waves above 10 kHz can be well confined in extracellular fluid–myelin sheath–intracellular fluid waveguide and propagate a distance of 7 mm without much attenuation. Our study may serve as one of the fundamental researches for the better understanding of the nervous system.

关键词： action potential propagation and axons neuronal wave propagation neuroscience electrodynamics in the nervous system

Generalized mixed finite element method for 3D elasticity problems

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Acta Mechanica Sinica 2018年第2期34卷 371-380页

作者： Guanghui qing Junhui Mao Yanhong liu college of Aeronautical Engineering Civil Aviation University of China

Without applying any stable element techniques in the mixed methods, two simple generalized mixed element(GME) formulations were derived by combining the minimum potential energy principle and Hellinger–Reissner(H–R) variational principle. The main features of the GME formulations are that the common c0-continuous polynomial shape functions for displacement methods are used to express both displacement and stress variables, and the coefficient matrix of these formulations is not only automatically symmetric but also invertible. Hence, the numerical results of the generalized mixed methods based on the GME formulations are stable. Displacement as well as stress results can be obtained directly from the algebraic system for finite element analysis after introducing stress and displacement boundary conditions simultaneously. Numerical examples show that displacement and stress results retain the same accuracy. The results of the noncompatible generalized mixed method proposed herein are more accurate than those of the standard noncompatible displacement method. The noncompatible generalized mixed element is less sensitive to element geometric distortions.

关键词： Minimum potential energy principle Hellinger–Reissner (H–R) variational principle Generalized variational principle Generalized mixed element (GME) Elasticity problem Noncompatible mode

A damage-coupled multi-axial time-dependent low cycle fatigue failure model for SS304 stainless steel at high temperature

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Acta Metallurgica Sinica(English letters) 2011年第2期24卷 169-174页

作者： Yujie lIU qing GAO Guozheng KANG School of Mechanics and Engineering Southwest Jiaotong University Chengdu 610031 China

Based on the time-dependent strain cyclic characteristics and fatigue behaviors of SS304 stainless steel under multi-axial cyclic loading at 700 ？ c, and in the frame of unified visoco-plastic cyclic constitutive model and continuum damage mechanics theory, the damage-coupled multi-axial time-dependent constitutive model and fatigue failure model were proposed. In the model, the evolution equation of damage was introduced in and the time-dependent effects, e.g. holding time, loading rate, were taken into account. The model was applied to the simulation of whole-life cyclic deformation behaviors and prediction of lcF life for SS304 stainless steel in multiaxial time-dependent low cycle fatigue tests. It is shown that the simulated results agree well with experimental ones.

关键词： SS304 stainless steel constitutive model low cycle fatigue Failure model Damage-coupled High temperature

Robust fault detection and optimization for a network of unmanned vehicles with imperfect communication channels

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chinese Journal of Aeronautics 2014年第1期27卷 65-75页

作者： Niu Erzhuo Wang qing Dong chaoyang School of Automation Science and Electrical Engineering Beihang University School of Aeronautical Science and Engineering Beihang University

The observer-based robust fault detection and optimization for a network of unmanned vehicles with imperfect communication channels and norm bounded modeling uncertainties are addressed. The network of unmanned vehicles is modeled as a discrete-time uncertain Markovian jump system. Based on the model, a residual generator is constructed and the sufficient condition for the existence of the desired fault detection filter is derived in terms of linear matrix inequality. Furthermore, a time domain optimization approach is proposed to improve the performance of the fault detection system. The problem of detecting small faults can be formulated as an optimization problem and its solution is given. For preventing false alarms, a new adaptive threshold function is established. The combined fault detection and optimization algorithm and the adaptive threshold are then applied to a network of highly maneuverable technology vehicles to illustrate the effective- ness of the orooosed aooroach.

关键词： Fault detection andoptimization Imperfect communicationchannel Network Uncertainty Unmanned vehicle

Antiproton production in heavy-ion collisions at subthreshold energies

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chinese Physics c 2020年第1期44卷 99-104页

作者： Zhao-qing Feng School of Physics and Optoelectronic Technology South China University of TechnologyGuangzhou 510641China

Within the framework of the lanzhou quantum molecular dynamics model,the deep subthreshold antiproton production in heavy-ion collisions has been investigated *** elastic scattering,annihilation and charge exchange reactions associated with antiproton channels are implemented in the *** attractive antiproton potential extracted from the G-parity transformation of nucleon selfenergies reduces the threshold energies in meson-baryon and baryon-baryon collisions,and consequently enhances the antiproton yields to some *** calculated invariant spectra are consistent with the available experimental *** primordial antiproton yields increase with the mass number of the colliding ***,annihilation reactions reduce the antiproton production which becomes independent of the colliding ***-flow phenomena of antiprotons correlated with the mean field potential and annihilation mechanism is found by comparing them with the proton *** experiments at the high-intensity heavy-ion accelerator facility(HIAF) in china are discussed.

关键词： antiproton production annihilation reactions anti-flow lQMD model