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Comments on Legal Developments for the Chinese Product Quality Guarantee--Concept,situation,problems and solutions

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China Standardization 2009年第5期54卷 16-21页

作者： Wang Huiping chen Jianxin chen shu This paper is one of the investiga-tive results in the items of AQSIQ aimed at improv-ing product quality）

The current legal system of product quality guarantee in China,with the"Three Guarantees" as its main form,has not yet met the demands of economic andsocial *** Chinese government needs to establish a more uniform andadvanced system based on the current *** article analyzes and discusses theconcept,current situation,existing problems and solutions in the context of the currentlegal system of product quality guarantee.

关键词： three guarantees warranty of product quality express warranty implied warranty

Global existence and stability of a stationary Mach reflection

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Science China Mathematics 2015年第1期58卷 11-34页

作者： chen shu Xing School of Mathematical Sciences Fudan University

We prove the global existence and stability of a wave structure containing a stationary Mach con- figuration, which occurs when an incident shock front hits a wall with a large incident angle. Our result shows that tile data of the upstream flow and the pressure at downstream part jointly determine the whole flow, as well a the wave structure. Particularly, we show that the height of the Mach stem depends not only on the data of upstream flow, but also on the pressure at downstream flow. The flow with the assigned wave structure is governed by a free boundary value problem for the Euler system. In the problem the location of the triple point, the shock fronts and the contact discontinuity are all unknown, they are finally determined together with the solution.

关键词： Euler system Mach reflection existence stability free boundary problem elliptic-hyperboliccomposcd system

Determination of respiration, gross nitrification and denitrification in soil profile using BaPS system

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Journal of Environmental Sciences 2006年第5期18卷 937-943页

作者： chen shu-tao HUANG Yao College of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 China LAPC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

A facility of BaPS （Barometric Process Separation） was used to determine soil respiration, gross nitrification and denitrification in a winter wheat field with depths of 0-7, 7--14 and 14-21 cm. N2O production was determined by a gas chromatograph. Crop root mass and relevant soil parameters were measured. Results showed that soil respiration and gross nitrification decreased with the increase of soil depth, while denitrification did not change significantly. In comparison with no-plowing plot, soil respiration increased significantly in plowing plot, especially in the surface soil of 0-7 cm, while gross nitrification and denitrification rates were not affected by plowing. Cropping practice in previous season was found to affect soil gross nitrification in the following wheat-growing season. Higher gross nitrification rate occurred in the filed plot with preceding crop of rice compared with that of maize for all the three depths of 0-7, 7-14 and 14-21 cm. A further investigation indicated that the nitrification for all the cases accounted for about 76% of the total nitrogen transformation processes of nitrification and denitrification and the N2O production correlated with nitrification significantly, suggesting that nitrification is a key process of soil N2O production in the wheat field. In addition, the variations of soil respiration and gross nitrification were exponentially dependent on root mass （p〈0.00l）.

关键词： soil respiration gross nitrification denitrification Barometric Process Separation (BaPS)

Correlation Function of Potts Model on Bethe Lattice

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Chinese Physics Letters 2000年第8期17卷 549-551页

作者： HAN Bing chen shu Institute of Physics and Center for Condensed Matter Physics Chinese Academy of SciencesBeijing 100080 Cryogenic Laboratory Chinese Academy of SciencesBeijing 100080

We exactly calculate the partition function and correlation function of Potts model on Bethe type lattice and discuss its phase *** calculation shows that the thermodynamic properties of Potts model on those Bethe lattices which is constructed via connecting the generators by single joint points has the similar character of one dimensional *** phase transition exists only at zero temperature and no finite temperature phase transition occurs.

关键词： transition. Bethe connecting

Spectral Dimension of a Modified Checker Board Fractal Lattice

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Chinese Physics Letters 1996年第5期13卷 325-328页

作者： chen shu YANG Zhan-ru CCAST(World Laboratory) P.O.Box 8730Beijing 100080 Department of Physics and Institute of Theoretical PhysicsBeijing Normal UniversityBeijing 100875

We present a kind of modified checker board lattice and investigate the random uualk on the frac *** spectral dimension is determined via renormalization procedures and the inverse matrix method is used to renormalize... 详细信息

关键词： random inverse Modified

Rare Earth Doped New Cemented Carbide with Ni-Co Binder for Mining

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Journal of Central South University 2000年第3期12卷 143-145页

作者： ZHANG Li chen shu Powder Metallurgy Factory Central South UniversityChangsha 410083China Changsha Research Institute of Mining and Metallurgy Changsha 410012China

A method, doping WC with La(NO 3) 3, of producing cemented carbide with rare earth was introduced. The effects of lanthanum on the mechanical properties and microstructure of WC 9(Co 75%Ni) cemented carbide were studied and a rock drilling experiment was carried *** experimental results show that both transverse rupture strength (TRS) and hardness of WC 9(Co 75%Ni) rare earth cemented carbides can match that of WC 9Co cemented carbide, when La 2O 3 / (Co+Ni) ratio is 0.3%, the abnormal growth of WC grain in the cemented carbide can be restrained effectively, the homogeneity of grain size in microstructure and the wear resistance are improved, which can be matchable to that of WC 9Co cemented carbide for mining.

关键词： cemented carbide rare earth cobalt substitution application

Exact mobility edges and topological phase transition in two-dimensional non-Hermitian quasicrystals

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Science China(Physics,Mechanics & Astronomy) 2022年第2期65卷 82-90页

作者： Zhi-Hao Xu Xu Xia shu chen Institute of Theoretical Physics and State Key Laboratory of Quantum Optics and Quantum Optics Devices Shanxi UniversityTaiyuan 030006China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China Chern Institute of Mathematics and LPMC Nankai UniversityTianjin 300071China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Yangtze River Delta Physics Research Center Liyang 213300China

The emergence of the mobility edge(ME)has been recognized as an important characteristic of Anderson *** difficulty in understanding the physics of the MEs in three-dimensional(3 D)systems from a microscopic image encourages the development of models in lower-dimensional systems that have exact *** most of the previous studies are concerned with one-dimensional(1 D)quasiperiodic systems,the analytic results that allow for an accurate understanding of two-dimensional(2 D)cases are *** this work,we disclose an exactly solvable 2 D quasicrystal model with parity-time(PT)symmetry displaying exact *** the thermodynamic limit,we unveil that the extended-localized transition point,observed at the PT symmetry breaking point,is topologically characterized by a hidden winding number defined in the dual *** coupling waveguide platform can be used to realize the 2 D non-Hermitian quasicrystal model,and the excitation dynamics can be used to detect the localization features.

关键词： quasicrystals mobility edges non-Hermitian systems localization properties

Temperature dependence of the P-hit single event transient pulse width in a three-transistor inverter chain

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Chinese Physics B 2012年第1期21卷 340-345页

作者： chen shu-Ming chen Jian-Jun School of Computer Science National University of Defense TechnologyChangsha 410073China

A comparison of the temperature dependence of the P-hit single event transient （SET） in a two-transistor （2T） inverter with that in a three-transistor （3T） inverter is carried out based on a three-dimensional numerical simulation. Due to the significantly distinct mechanisms of the single event change collection in the 2T and the 3T inverters, the temperature plays different roles in the SET production and propagation. The SET pulse will be significantly broadened in the 2T inverter chain while will be compressed in the 3T inverter chain as temperature increases. The investigation provides a new insight into the SET mitigation under the extreme environment, where both the high temperature and the single event effects should be considered. The 3T inverter layout structure （or similar layout structures） will be a better solution for spaceborne integrated circuit design for extreme environments.

关键词： temperature dependence single event transient parasitic bipolar amplification effect,charge sharing collection

Exact solutions of non-Hermitian chains with asymmetric long-range hopping under specific boundary conditions

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Chinese Physics B 2022年第1期31卷 81-86页

作者： Cui-Xian Guo shu chen Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Yangtze River Delta Physics Research Center Liyang 213300China

We study the one-dimensional general non-Hermitian models with asymmetric long-range hopping and explore how to analytically solve the systems under some specific boundary *** the introduction of long-range hopping terms prevents us from finding analytical solutions for arbitrary boundary parameters,we identify the existence of exact solutions when the boundary parameters fulfill some constraint relations,which give the specific boundary *** analytical results show that the wave functions take simple forms and are independent of hopping range,while the eigenvalue spectra display rich model-dependent ***,we find the existence of a special point coined as pseudo-periodic boundary condition,for which the eigenvalues are the same as those of the periodical system when the hopping parameters fulfill certain conditions,whereas the eigenstates display the non-Hermitian skin effect.

关键词： non-Hermitian physics exact solution topological physics long-range hopping