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Journal of Hydrodynamics 2011年第6期23卷 759-766页

作者： ZHANG Lie-hui, GUO Jing-jing, LIU Qi-guo State Key Laboratory of Reservoir Geology and Exploitation, Southwest Petroleum University, chengdu 610500, China State Key Laboratory of Reservoir Geology and Exploitation Southwest Petroleum University Chengdu 610500 China

This article presents a new well test model for stress-sensitive composite dual-porosity reservoirs based on the concept of permeability modulus, where the rock and fluid properties as well as the formation thickness vary in the radial direction. An analytical solution in the Laplace space for the pressure-transient behavior for a line-source, constant-rate well of this type of reservoir is obtained with the Laplace transformation and the perturbation technique. The pressure and its derivative in the reservoir and the effects of relevant parameters on the pressure-transient response are obtained. The model as well as the corresponding type curves may be used in predicting the production performance or analyzing the production data for this type of reservoir.

关键词： non-uniform thickness stress-sensitive composite dual-porosity well test model type curve

Effect of high glucose levels on the calcification of vascular smooth muscle cells by inducing osteoblastic differentiation and intracellular calcium deposition via BMP-2/Cbfα-1 pathway

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第12期11卷 905-911页

作者： Fang LIU Hui ZHONG Jing-yuan LIANG Ping FU Zhi-juan LUO Li ZHOU Rong GOU Jun HUANG Division of Nephrology West China Hospital Sichuan University Chengdu 610041 China

In this paper, we investigate the effect and the possible mechanism of high glucose levels on the calcification of human aortic smooth muscle cells （HASMCs）. HASMCs were divided into four groups： normal glucose group （NG）, osmolality control group （OC）, high glucose group （HG, HASMCs culture medium containing 30 mmol/L glucose）, and high glucose plus recombinant human Noggin protein （bone morphogenetic protein-2 （BMP-2） antagonist） group （HN）. The mRNA levels and the protein expressions of BMP-2 and core binding factor alpha-1 （Cbfa-1） were measured by real-time quantitative polymerase chain reaction （PCR） and Western blot. After induced by 10 mmol/L β-glycerol phosphoric acid, cells were had＇vested for assessments of alkaline phosphatase （ALP） activities at Days 1,2, and 3, and intracellular calcium contents at Days 7 and 14, respectively. High glucose levels increased the mRNA levels and the protein expressions of BMP-2 and Cbfa-1 （P〈0.05）. The expression of Cbfa-1 was partially blocked by Noggin protein （P〈0.05）, while BMP-2 was not （P〉0.05）. After being induced by β-glycerol phosphoric acid, high glucose levels increased the ALP activity [（48.63±1.03） vs. （41.42±2.28） U/mg protein, Day 3; P〈0.05] and the intracellular calcium content [（2.76±0.09） vs. （1.75±0.07） μmol/mg protein, Day 14; P〈0.05] in a time-dependent manner when compared with the NG group, while the ALP activity could not be blocked by Noggin protein [（48.63±1.03） vs. （47.37±0.97） U/mg protein, Day 3; P〉0.05]. These results show that high glucose levels can evoke the calcification of HASMCs by inducing osteoblastic trans-differentiation and intracellular calcium deposition via the BMP-2/Cbfa-1 pathway, which can be partially blocked by Noggin protein.

关键词： Bone morphogenetic protein (BMP) Core binding factor alpha-1 (Cbfa-1) Vascular smooth muscle cell,Noggin protein

Dioxygen Affinities and Catalytic Epoxidation Performanceof Transition-Metal Hydroxamates

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Chinese Chemical Letters 1999年第1期10卷 79-82页

作者： Hua YANG Sheng Ying QIN Xiao Xia LU(Department of Chemistry, Sichuan University, chengdu 610064) Sichuan Univ Dept Chem Chengdu 610064 Peoples R China

The dioxygen affinities and catalytic epoxidation performance of transition-metal hydroxamates were investigated for the first time. The effects of substituents on these properties were also discussed in the paper.

关键词： transition-metal hydroxamates dioxygen affinities catalytic epoxidation

A new C_(27)-steroidal glycoside from Ophiopogon japonicus

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Chinese Chemical Letters 2008年第1期19卷 82-84页

作者： Jian Zhong Wang Li Ming Ye Xiao Bing Chen West China College of Pharmacy Sichuan University Chengdu 610041 China

A new C27-steroidal glycoside with three known compounds were isolated from the tuber of Ophiopogonjaponicus （Thunb.） Ker-Gawl. Based on the spectral analysis, including HRMS, 1H NMR, 13C NMR, DEPT, 1H-1H COSY, HMQC and HMBC, their chemical structures were determined as pennogenin-3-O-α-L-rhamnopyranosyl-（1→ 2）-β-D-xylopyranosyl-（1→ 4）-13-D-gluco- pyranoside （1）, pennogenin-3-O-α-L-rhamnopyranosyl-（1→ 2）-β-D-glucopyranoside （2）, ophiopojaponin C （3） and ophiopogonin D （4）. 2007 Jian Zhong Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Ophiopogon japonicus C27-steroidal glycoside

Neural Network Based Adaptive Tracking of Nonlinear Multi-Agent System

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Journal of Electronic Science and Technology 2021年第2期19卷 144-154页

作者： Bo-Xian Lin Wei-Hao Li Kai-Yu Qin Xi Chen School of Aeronautics and Astronautics University of Electronic Science and Technology of ChinaChengdu 611731

In this paper,the problems of robust consensus tracking control for the second-order multi-agent system with uncertain model parameters and nonlinear disturbances are *** adaptive control strategy is proposed to smooth the agent’s trajectory,and the neural network is constructed to estimate the system’s unknown *** consensus conditions are demonstrated for tracking a leader with nonlinear dynamics under an adaptive control algorithm in the absence of model ***,the results are extended to the system with unknown time-varying disturbances by applying the neural network estimation to compensating for the uncertain parts of the agents’*** laws are designed based on the Lyapunov function terms to ensure the effectiveness of robust ***,the theoretical results are verified by numerical simulations,and a comparative experiment is conducted,showing that the trajectories generated by the proposed method exhibit less oscillation and converge faster.

关键词： Coordinated tracking leader following consensus neural network based adaptive control robust control uncertain nonlinear system

A critical transition rule for broadening exponent of fluctuation and its effect on dissipation in chemical reaction-heat conduction coupling systems

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Science China Chemistry 2011年第5期54卷 774-781页

作者： LIN Feng ZHAO NanRong LUO JiuLi Institute of Chemical Physics College of ChemistrySichuan UniversityChengdu 610064China

A stochastic model of chemical reaction-heat conduction-diffusion for a one-dimensional gaseous system under Dirichlet or zero-fluxes boundary conditions is proposed in this paper. Based on this model,we extend the theory of the broadening exponent of critical fluctuations to cover the chemical reaction-heat conduction coupling systems as an asymptotic property of the corresponding Markovian master equation (ME),and establish a valid stochastic thermodynamics for such systems. As an illustration,the non-isothermal and inhomogeneous Schl-gl model is explicitly studied. Through an order analysis of the contributions from both the drift and diffusion to the evolution of the probability distribution in the corresponding Fokker-Planck equation(FPE) in the approach to bifurcation,we have identified the critical transition rule for the broadening exponent of the fluctuations due to the coupling between chemical reaction and heat conduction. It turns out that the dissipation induced by the critical fluctuations reaches a deterministic level,leading to a thermodynamic effect on the nonequilibrium physico-chemical processes.

关键词： stochastic model of chemical reaction–heat conduction–diffusion systems stochastic thermodynamics of chemical reaction–heat conduction coupling processes broadening exponent of critical fluctuation entropy production of fluctuations fluctuation–dissipation effect

AB INITIO STUDY OF 1,2-DITHIOSQUARIC ACID

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Chinese Chemical Letters 1996年第1期7卷 59-62页

作者： Li Xin ZHOU Jing Lai ZHANG An Min TIAN Guo Sen YAN (Department of CHEMISTRY, Sichuan University chengdu, 610064). SICHUAN UNIV DEPT CHEMCHENGDU 610064PEOPLES R CHINA

Result of ab initio SCF calculation of 1,2-dithiosquaric acid (3,4-dihydroxy-3-cyclobutene-1,2-dithione) are reported. The ZZ isomer is found to be the most stable of the three isomers. An isodesmic energy analysis has been carried out at the HF 6-31G*//6-31G* level for the three planar isomers. The three isomers have positive isodesmic energies or small negative ones, suggesting that 1,2-dithiosquaric acid is not aromatic. Vibrational frequencies have also been calculated for the three isomers.

关键词： ACID AB INITIO STUDY OF 1,2-DITHIOSQUARIC ACID

Deep-seated large-scale toppling failure in metamorphic rocks：a case study of the Erguxi slope in southwest China

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Journal of Mountain Science 2016年第12期13卷 2094-2110页

作者： LIU Ming LIU Fang-zhou HUANG Run-qiu PEI Xiang-jun State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China School of Civil and Environmental Engineering Georgia Institute of Technology Atlanta GA 30332 USA

Deep-seated large-scale toppling failure presents unique challenges in the study of natural slope deformation process in mountainous *** active deep-seated toppling process was identified in the Erguxi slope located in southwest China,which affected a large area and damaged critical transportation infrastructure with the volume of the deforming rock mass exceeding 24×10~6 m^*** poses significant risks to the downstream Shiziping Hydropower Station by damming the Zagunao *** investigation and monitoring results indicate that the deformation of the Erguxi slope is in the advanced stage of deep-seated toppling process,with the formation of a disturbed belt but no identifiable master failure *** was postulated that the alternating tensile and shear strength associated with the hard/soft laminated rock strata of metasandstone and phyllite layers preclude the development of either a tensile or shear failure surface,which resulted in the continuous deformation and displacement without a catastrophic mass *** slope movement is in close association with the unfavorable geological conditions of the study area in addition to the construction of transportation infrastructure and the increase of the reservoir *** the basis of the mechanism and intensity of the ongoing toppling deformation,a qualitative grading system was proposed to describe the toppling process and toevaluate the slope *** paper summarized the field observation and monitoring data on the toppling deformation for better characterizing its effect on the stability of the Erguxi *** qualitative grading system intends to provide a basis for quantitative study of large-scale deep-seated toppling process in metamorphic rocks.

关键词： Deep-seated slope deformation Largescale toppling Slope stability Metamorphic rock

Research on the energy consumption mechanism and characteristics of the gallium indium tin liquid metal arcing process

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Plasma Science and Technology 2023年第9期25卷 104-113页

作者：马亚光高国强向宇彭伟董克亮钱鹏宇游炳妍杨泽锋魏文赋吴广宁 School of Electrical Engineering Southwest Jiaotong UniversityChengdu 610031People’s Republic of China

For high-voltage direct current(HVDC)power grid transmission with higher voltages,the energyconsuming branch of the DC circuit breaker is required to dissipate huge energies of more than megajoules in a short time in the case of a fault and short *** requirements for huge volume and weight are difficult to meet with energy-consuming equipment based on *** this paper,a new energy consumption method is proposed based on gallium indium tin(GaInSn)liquid metal in the arcing process,and a test platform with adjustable short-circuit current is *** mechanism triggering GaInSn liquid metal arcing energy consumption is *** is found that short-circuit current and channel aperture are the key parameters affecting the energy consumption of liquid metal *** characteristics of GaInSn liquid metal energy consumption are investigated,and four stages of liquid metal energy consumption are found:oscillatory shrinkage,arc breakdown,arc burning phase change and arc *** influence of short-circuit current and channel aperture on the energy consumption characteristics of GaInSn liquid metal is *** further explore the physical mechanism of the above phenomena,a magneto-hydrodynamic model of energy consumption in the GaInSn liquid metal arcing process is *** influence of short-circuit current and channel aperture on the temperature distribution of the liquid metal arc is *** mechanism of the effect of short-circuit current and channel aperture on peak arc temperature and the temperature diffusion rate is *** research results provide theoretical support for this new liquid metal energy consumption mode DC circuit breaker.

关键词： GaInSn liquid metal trigger mechanism oscillatory shrinkage arcing energy consumption temperature diffusion

Analyzing topics in social media for improving digital twinning based product development

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Digital Communications and Networks 2024年第2期10卷 273-281页

作者： Wenyi Tang Ling Tian Xu Zheng Ke Yan School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China

Digital twinning enables manufacturers to create digital representations of physical entities,thus implementing virtual simulations for product *** efforts of digital twinning neglect the decisive consumer feedback in product development stages,failing to cover the gap between physical and digital *** work mines real-world consumer feedbacks through social media topics,which is significant to product *** specifically analyze the prevalent time of a product topic,giving an insight into both consumer attention and the widely-discussed time of a *** primary body of current studies regards the prevalent time prediction as an accompanying task or assumes the existence of a preset ***,these proposed solutions are either biased in focused objectives and underlying patterns or weak in the capability of generalization towards diverse *** this end,this work combines deep learning and survival analysis to predict the prevalent time of *** propose a specialized deep survival model which consists of two *** first module enriches input covariates by incorporating latent features of the time-varying text,and the second module fully captures the temporal pattern of a rumor by a recurrent network ***,a specific loss function different from regular survival models is proposed to achieve a more reasonable *** experiments on real-world datasets demonstrate that our model significantly outperforms the state-of-the-art methods.

关键词： Digital twinning Product development Topic analysis Social media