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Dynamics and Thermodynamics of Porous HMX-like Material Under Shock

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Communications in Theoretical Physics 2009年第11期52卷 901-908页

作者： XU Ai-Guo ZHANG Guang-Cai ZHANG Ping PAN Xiao-Fei zhu jian-shi National Key Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics P.O.Box 8009-26 Beijing 100088 China

Strong shock may induce complex processes in porous materials. We use the newly developed materialpoint-method to simulate such processes in an HMX-like material. To pick out relevant information, morphological characterization is used to treat with the temperature map. Via the Minkowski funetional analysis the dynamics and thermodynamics of the shock wave reaction on porous HMX-like material are studied. The geometrical and topological properties of the ＂hot-spots＂ are revealed. Numerical results indicate that, shocks in porous materials are not simple jump states as classically viewed, but rather are a complex sequence of compressions and rarefactions. They cover a broad spectrum of states. We can use coarse-grained description to the wave series. A threshold value of temperature presents a Turing pattern dynamical procedure. A higher porosity is generally preferred when the energetic material needs a higher temperature for initiation. The technique of data analysis can be used to other physical quantities, for example, density, particle velocity, some specific stress, etc. From a series of studies along the line, one may get a large quantity of information for desiring the fabrication of material and choosing shock strength according to what needed is scattered or connected ＂hot-spots＂. PACS numbers： ***, 05 Key words： porous material 70.-a, 05.40.-a, *** shock wave, Minkowski functionals

关键词： porous material shock wave Minkowski functionals

Three-Dimensional Multi-mesh Material Point Method for Solving Collision Problems

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Communications in Theoretical Physics 2008年第5期49卷 1129-1138页

作者： PAN Xiao-Fei XU Ai-Guo ZHANG Guang-Cai ZHANG Ping zhu jian-shi MA Shang ZHANG Xiong Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics P.O. Box 8009-26 Beijing 100088 China School of Aerospace Tsinghua University Beijing 100084 China

A new multi-mesh contact algorithm for three-dimensional material point method is presented. The contact algorithm faithfully recovers the opposite acting forces between colliding bodies. Collision procedures between regular bodies and/or rigid bodies are treated within the same framework. Multi-value of momentum and mass are defined on every node to describe the contact/sliding/separation procedure. Both normal and tangential velocities of each particle at the contact surface are calculated in respective individual mesh. A Coulomb friction is applied to describe the sliding or slipping between the contacting bodies. The efficiency of the contact algorithm is linearly related to the number of the contacting bodies because the overlapped nodes are labeled by sweeping the material particles of all bodies when the nodal momentum and mass are formed at every time step. Numerical simulation shows that our contact algorithm possesses high accuracy and low numerical energy dissipation, which is very important for solving collision problems.

关键词： material-point method (MPM) energy conservation contact algorithm multi-mesh

Effective utilization of dolomitic lead-zinc waste rock by replacing dolomite as flux in iron ore sintering process

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Journal of Iron and Steel Research International 2024年第8期31卷 1861-1872页

作者： Xin Wang Cong-cong Yang jian Pan De-qing zhu Zheng-qi Guo Guang-hui Xia shi-juan Qu School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Low-Carbon and Hydrogen Metallurgy Research Center Central South UniversityChangsha 410083HunanChina

With increasingly stringent environmental protection policies,cost-effective and value-added treatment of massive lead-zinc waste rock(LZWR)generated from the preconcentration process has attracted substantial attention.A type of dolomitic LZWR with 18 wt.%MgO,27 wt.%CaO,0.29 wt.%Zn and 1.43 wt.%S was used as a replacement flux in the iron ore sintering *** sinter pot tests were carried out based on an industrial ore *** results show that replacing 0%-60%of dolomite with LZWR does not adversely affect the sintering productivity,fuel consumption rate,and the quality of the sinter products,while the Zn and S elements contained in LZWR can be effectively removed with the residual Zn and S contents of the resultant sinter products being less than 0.02 and 0.055 wt.%,***,substituting LZWR for dolomite as a flux inevitably increases the SO_(2) concentration in the sintering flue gas due to its high sulfur *** the processing capacity of the sintering flue gas desulfurization system,the replacement ratio of dolomite can reach 40%,equal to LZWR consumption of 24.3 kg per ton of *** SO_(2) in sintering flue gas can be recovered to produce(NH_(4))_(2)SO_(4) or HSO_(4),while the volatilized Zn collected into the zinc-containing dust can be subsequently recycled by the rotary hearth furnace ***,it is technologically and economically feasible to use the LZWR as a replacement flux in the iron ore sintering process,providing a new way for the safe,large-scale and low-cost treatment of LZWR.

关键词： Lead Zinc waste rock Dolomite Sintering Flue gas Sinter product

Insufficient TRPM5 Mediates Lipotoxicity-induced Pancreaticβ-cell Dysfunction

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Current Medical Science 2024年第2期44卷 346-354页

作者： Kai-yuan WANG shi-mei WU Zheng-jian YAO Yun-xia zhu Xiao HAN Key Laboratory of Human Functional Genomics of jiangsu Province Department of Biochemistry and Molecular BiologyNanjing Medical UniversityNanjing 211166China

Objective:While the reduction of transient receptor potential channel subfamily M member 5(TRPM5)has been reported in islet cells from type 2 diabetic(T2D)mouse models,its role in lipotoxicity-induced pancreaticβ-cell dysfunction remains *** study aims to study its ***:Pancreas slices were prepared from mice subjected to a high-fat-diet(HFD)at different time points,and TRPM5 expression in the pancreaticβcells was examined using immunofluorescence ***-stimulated insulin secretion(GSIS)defects caused by lipotoxicity were mimicked by saturated fatty acid palmitate(Palm).Primary mouse islets and mouse insulinoma MIN6 cells were treated with Palm,and the TRPM5 expression was detected using qRT-PCR and Western ***-induced GSIS defects were measured following siRNA-based Trpm5 *** detrimental effects of Palm on primary mouse islets were also assessed after overexpressing Trpm5 via an adenovirus-derived Trpm5(Ad-Trpm5).Results:HFD feeding decreased the mRNA levels and protein expression of TRPM5 in mouse pancreatic *** reduced TRPM5 protein expression in a time-and dose-dependent manner in MIN6 *** also inhibited TRPM5 expression in primary mouse *** of Trpm5 inhibited insulin secretion upon high glucose stimulation but had little effect on insulin *** of Trpm5 reversed Palm-induced GSIS defects and the production of functional maturation molecules unique toβ***:Our findings suggest that lipotoxicity inhibits TRPM5 expression in pancreaticβcells both in vivo and in vitro and,in turn,drivesβ-cell dysfunction.

关键词： type 2 diabetes β-cell dysfunction lipotoxicity TRPM5

Design strategies and recent advancements of solid-state supercapacitor operating in wide temperature range

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Carbon Energy 2024年第6期6卷 248-281页

作者： Jie Zhou Zhengfeng zhu Wenhui shi Xiangyu shi zhuoyuan Zheng Ye Xiong Yusong zhu School of Energy Science and Engineering Nanjing Tech UniversityNanjingJiangsuChina Kucap Smart Technology(Nanjing)Co. Ltd.NanjingJiangsuChina

Solid-state supercapacitors(SSCs)are emerging as one of the promising energy storage devices due to their high safety,superior power density,and excellent cycling ***,performance degradation and safety issues under extreme conditions are the main challenges for the practical *** the expansion of human activities,such as space missions,polar exploration,and so on,the investigation of SSC with wide temperature tolerance,high energy density,power density,and sustainability is highly *** this review,the effects of temperature on SSC are systematically illustrated and clarified,including the properties of the electrolyte,ion diffusion,and reaction dynamics of the ***,we summarize the recent advances in wide-temperature-range SSCs from the aspect of electrolyte modification,electrode design,and interface adjustment between electrode and electrolyte,especially with critical concerns on ionic conductivity and cycling *** the end,a perspective is presented,expecting to promote the practical application of the SSC in harsh conditions.

关键词： electrode interface solid-state electrolyte solid-state supercapacitor wide temperature

Fluid property identification of the Lower Cretaceous reservoirs with complex oil-water contacts in Deseo Basin,Chad

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Energy Geoscience

Energy Geoscience 2024年第1期5卷 89-98页

作者： Xinxin Zhang Lianfeng zhu Tianjiao Wang Xiaokang shi Bo Han jian Shen Hailei Gao Mud logging company Great Wall Drilling Company Ltd.CNPCLiaoningPanjin124010China CNPC Latin America Ltd. Beijing100034China CNPC Andes(Ecuador)Ltd. Beijing100034China

Recently,exploration breakthroughs have been made in the Lower Cretaceous sandstone reservoirs in the Doseo Basin,but the identification of reservoir fluid property is difficult due to variable reservoir lithology,complex oil-water contact within and faint responses of the oil zone,which causes the lower accuracy of reservoir fluid property identification with conventional mudlogging and wirelogging *** the geochemical logging,fluorescent logging,mud logging and cutting logging technology,in combination with formation test data,this paper distinguishes the crude oil types,analyzes the logging response characteristics of oil zone after water washing,and establishes the interpretation charts and parameter standards for reservoir fluid *** crude oil can be divided into two types,namely viscous-heavy and thin-light,based on total hydrocarbon content and component concentration tested by mud logging,features of pyrolysis gas chromatogram and fluorescence *** general characteristics of oil layers experienced water washing include the decrease of total hydrocarbon content and component concentration from mud logging,the decrease of S1 and PS values from geochemical logging,the decrease of hydrocarbon abundance and absence of some light components in pyrolysis gas chromatogram,and the decrease of fluorescence area and intensity from fluorescence *** to crude oil types,the cross plots of S1 versus peak-baseline ratio,and the cross plots of rock wettability versus fluorescence area ratio are drawn and used to interpret reservoir fluid ***,the standards of reservoir fluid parameter are established combining with the parameters of PS and the parameters in above charts,and comprehensive multiparameter correlation in both vertical and horizontal ways is also performed to interpret reservoir fluid *** application in the Doseo Basin achieved great success,improving interpretation ability of fluid property

关键词： Doseo Basin Reservoir interpretation Oil-water contact Fluid property Crude oil type

Diffractive neural networks with improved expressive power for gray-scale image classification

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Photonics Research 2024年第6期12卷 1159-1166页

作者： MINJIA ZHENG WENZHE LIU LEI shi jian ZI State Key Laboratory of Surface Physics Key Laboratory of Micro-and Nano-Photonic Structures(Ministry of Education)and Department of PhysicsFudan UniversityShanghai 200433China Institute for Nanoelectronic Devices and Quantum Computing Fudan UniversityShanghai 200433China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China Shanghai Research Center for Quantum Sciences Shanghai 210315China

In order to harness diffractive neural networks(DNNs)for tasks that better align with real-world computer vision requirements,the incorporation of gray scale is ***,DNNs are not powerful enough to accomplish gray-scale image processing tasks due to limitations in their expressive *** our work,we elucidate the relationship between the improvement in the expressive power of DNNs and the increase in the number of phase modulation layers,as well as the optimization of the Fresnel number,which can describe the diffraction *** demonstrate this point,we numerically trained a double-layer DNN,addressing the prerequisites for intensitybased gray-scale image ***,we experimentally constructed this double-layer DNN based on digital micromirror devices and spatial light modulators,achieving eight-level intensity-based gray-scale image classification for the MNIST and Fashion-MNIST data *** optical system achieved the maximum accuracies of 95.10%and 80.61%,respectively.

关键词： process mirror limitations

Exploring predictive markers for liver failure post-hepatectomy in hepatocellular carcinoma patients

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1482-1484页

作者： shi-Yan Zhang Xiong-jian Ma Xue-Xia zhu Na Cai Department of Clinical Laboratory Fuding HospitalFujian University of Traditional Chinese MedicineFuding 355200Fujian ProvinceChina

This letter to the editor addresses the study titled“Predictive value of NLR,Fib4,and APRI in the occurrence of liver failure after hepatectomy in patients with hepatocellular carcinoma”by Kuang et al in the World Journal of Gastrointestinal *** study acknowledges the comprehensive patient data analysis while suggesting that there is a need for further discussion on the clinical applicability of these markers across diverse patient *** letter recommends prospective studies for validation and considers the influence of confounding *** finding underscores the significance of this study in improving hepatocellular carcinoma management.

关键词： Neutrophil-to-lymphocyte ratio Hepatocellular carcinoma Liver failure Hepatectomy Letter to the Editor Commentary

Mastering air combat game with deep reinforcement learning

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Defence Technology（防务技术） 2024年第4期34卷 295-312页

作者： Jingyu zhu Minchi Kuang Wenqing Zhou Heng shi Jihong zhu Xu Han Department of Precision Instruments Tsinghua UniversityBeijing 100084China Department of Computer Science and Technology Tsinghua UniversityBeijing 100084China Chengdu Aircraft Design&Research Institute Aviation Industry Corporation of ChinaChengdu 610000China

Reinforcement learning has been applied to air combat problems in recent years,and the idea of curriculum learning is often used for reinforcement learning,but traditional curriculum learning suffers from the problem of plasticity loss in neural *** loss is the difficulty of learning new knowledge after the network has *** this end,we propose a motivational curriculum learning distributed proximal policy optimization(MCLDPPO)algorithm,through which trained agents can significantly outperform the predictive game tree and mainstream reinforcement learning *** motivational curriculum learning is designed to help the agent gradually improve its combat ability by observing the agent's unsatisfactory performance and providing appropriate rewards as a ***,a complete tactical maneuver is encapsulated based on the existing air combat knowledge,and through the flexible use of these maneuvers,some tactics beyond human knowledge can be *** addition,we designed an interruption mechanism for the agent to increase the frequency of decisionmaking when the agent faces an *** the number of threats received by the agent changes,the current action is interrupted in order to reacquire observations and make decisions *** the interruption mechanism can significantly improve the performance of the *** simulate actual air combat better,we use digital twin technology to simulate real air battles and propose a parallel battlefield mechanism that can run multiple simulation environments simultaneously,effectively improving data *** experimental results demonstrate that the agent can fully utilize the situational information to make reasonable decisions and provide tactical adaptation in the air combat,verifying the effectiveness of the algorithmic framework proposed in this paper.

关键词： Air combat MCLDPPO Interruption mechanism Digital twin Distributed system