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A prediction method for the performance of a low-recoil gun with front nozzle

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Defence Technology（防务技术） 2019年第5期15卷 703-712页

作者： Cheng Cheng Chong Wang xiaobing zhang School of Energy and Power Engineering Nanjing University of Science and Technology

One of the greatest challenges in the design of a gun is to balance muzzle velocity and recoil,especially for guns on aircrafts and deployable *** resolve the conflict between gun power and recoil force,a concept of rarefaction wave gun(RAVEN)was proposed to significantly reduce the weapon recoil and the heat in barrel,while minimally reducing the muzzle *** main principle of RAVEN is that the rarefaction wave will not reach the projectile base until the muzzle by delaying the venting time of an expansion nozzle at the *** on the RAVEN principle,the purpose of this paper is to provide an engineering method for predicting the performance of a low-recoil gun with front ***,a two-dimensional two-phase flow model of interior ballistic during the RAVEN firing cycle was *** simulation results were compared with the published data to validate the reliability and ***,the effects of the vent opening times and locations were investigated to determine the influence rules on the performance of the RAVEN with front *** according to the results above,simple nonlinear fitting formulas were provided to explain how the muzzle velocity and the recoil force change with the vent opening time and ***,a better vent venting opening time corresponding to the vent location was *** findings should make an important contribution to the field of engineering applications of the RAVEN.

关键词： Interior ballistic Low recoil Rarefaction wave Prediction method Two-dimensional

Preparation of Fe–Co based MOF-74 and its effective adsorption of arsenic from aqueous solution

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Journal of Environmental Sciences 2019年第6期31卷 197-207页

作者： Jianqiang Sun xiaobing zhang Anping zhang Chunyang Liao Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province College of Environment Zhejiang University of Technology State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

To obtain a cost-effective adsorbent for the removal of arsenic in water,a novel nanostructured Fe–Co based metal organic framework(MOF-74)adsorbent was successfully prepared via a simple solvothermal *** adsorption experiments showed that the optimal molar ratio of Fe/Co in the adsorbent was 2:*** Fe_2Co_1MOF-74 was characterized by various techniques and the results showed that the nanoparticle diameter ranged from60 to 80 nm and the specific surface area was 147.82 m^2/*** isotherm and kinetic parameters of arsenic removal on Fe_2Co_1MOF-74 were well-fitted by the Langmuir and pseudo-second-order *** maximum adsorption capacities toward As(III)and As(V)were 266.52 and 292.29 mg/g,*** presence of sulfate,carbonate and humic acid had no obvious effect on arsenic ***,coexisting phosphate significantly hindered the removal of arsenic,especially at high concentrations(10 mmol/L).Electrostatic interaction and hydroxyl and metal–oxygen groups played important roles in the adsorption of ***,the prepared adsorbent had stable adsorption ability after regeneration and when used in a real-water *** excellent adsorption performance of Fe_2Co_1MOF-74 material makes it a potentially promising adsorbent for the removal of arsenic.

关键词： Fe-Co MOF-74 Adsorbent Arsenite Arsenate Removal

Recent advances in DNAzyme-based gene silencing

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Science China Chemistry 2017年第5期60卷 591-601页

作者： Huanhuan Fan xiaobing zhang Yi Lu Molecular Science and Biomedicine Laboratory State Key Laboratory of Chemo/Bio-Sensing and Chemometrics Collaborative Innovation Center for Chemistry and Molecular MedicineCollege of Chemistry and Chemical Engineering College of Biology Hunan University Changsha 410082 China Department of Chemistry Materials Science and Engineering University of Illinois at Urbana-Champaign Urbana Illinois 61801 USA

DNAzymes, generated through in vitro selection processes, are single-stranded DNA catalysts that can catalyze a wide variety of reactions, such as RNA or DNA cleavage and ligation or DNA phosphorylation. Based on specific cofactor dependence and potent catalytic ability, DNAzymes have been extensively used to develop highly sensitive and specific sensing platforms for metal ions,small molecules, and biomacromolecules. However, in spite of their multiple strong enzymatic turnover properties, few reports have addressed the potential application of RNA-cleaving DNAzymes as therapeutic gene-silencing agents. The main challenges are being met with low efficiency of cellular uptake, instability and the lack of sufficient cofactors for cellular or in vivo study, which have limited the development of DNAzymes for clinical application. In recent years, substantial progress has been made to enhance the delivery efficiency and stability of DNAzymes by developing variety of methods. Smart metal oxide nanomaterials have also been used to meet the requirement of cofactors in situ. This review focuses on the gene silencing application of DNAzymes as well as their physicochemical properties. Methods of increasing the efficacy of DNAzymes in gene therapy are also discussed: delivery systems to enhance the cellular uptake, modifications to enhance the stability and smart systems to generate sufficient cofactors in situ. Finally, some future trends and perspectives in these research areas are outlined.

关键词： DNAzymes gene-silencing delivery stability cofactors

Numerical investigation on cooling performance of filter in a pyrotechnic gas generator

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Defence Technology（防务技术） 2021年第2期17卷 343-351页

作者： Cheng Cheng xiaobing zhang Chong Wang Lu Wang School of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing210094China

As a key part of the pyrotechnic gas generator,the filter not only removes the particulate matter but also cools the hot gas to a safe *** paper aims to improve the understanding of the basic heat and flow phenomenon in the gas *** pyrotechnic gas generator is modelling by a simplified filter structure with fiber arrays.A finite-volume model of the heat and fluid flow is proposed to simulate the detailed multi-dimensional flow and energy conversion *** verification results are in good agreement with data in different *** results demonstrate that the filter can not only absorb heat from the gas but also cause the high intensity enhancement of the heat *** performance difference between inline and staggered arrays is also *** findings of the study put a further prediction tool for the understanding and design of the filter system with fibers.

关键词： Pyrotechnic gas generator Cooling performance Filter Metal fiber

Impact of Morphology of Conductive Agent and Anode Material on Lithium Storage Properties

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Nano-Micro Letters 2015年第4期7卷 360-367页

作者： xiaobing zhang Ji Ma Kezheng Chen Lab of Functional and Biomedical Nanomaterials College of Materials Science and Engineering Qingdao University of Science and Technology

In this study,the impact of morphology of conductive agent and anode material(Fe3O4)on lithium storage properties was throughly *** and belt-like Fe3O4active materials were separately blended with two kinds of conductive agents(i.e.,granular acetylene black and multi-walled carbon nanotube)as anodes in lithium-ion batteries(LIBs),*** was found that the morphology of conductive agent is of utmost importance in determining LIBs storage *** contrast,not as the way we anticipated,the morphology of anode material merely plays a subordinate role in their electrochemical ***,the morphology-matching principle of electrode materials was discussed so as to render their utilization more rational and effective in LIBs.

关键词： Lithium-ion batteries Morphology Conductive agent Anode material

Nanocarrier based on the assembly of protein and antisense oligonucleotide to combat multidrug resistance in tumor cells

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Science China Chemistry 2017年第10期60卷 1318-1323页

作者： Xuan Yu Liang Gong Jing zhang Zilong Zhao xiaobing zhang Weihong Tan Molecular Science and Biomedicine Laboratory State Key Laboratory for Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering College of Life Sciences and Aptamer Engineering Center of Hunan Province Hunan University Changsha 410082 China

Chemotherapy-induced multi-drug resistance(MDR) in tumors poses a huge challenge for clinical treatment of tumors. The downregulation of the multi-drug resistance relative protein, represented by P-glycoprotein(P-gp), can reverse MDR of cancer cells. In this study, we developed doxorubicin-loading nanocarrier based on the assembly of protein and antisense oligonucleotide(ASO) to combat MDR of cancer cells. The data demonstrate that the nanocarrier can efficiently deliver ASO to cytoplasm and downregulate the P-glycoprotein expression, subsequently improving the therapeutic effects of Dox in doxorubicin-resistant MCF-7/ADR cancer cells. The preparation is simple and effective, providing a powerful tool for gene delivery. Therefore, our nanocarrier shows high promise in cancer treatment.

关键词： multi-drug resistance P-glycoprotein antisense oligonucleotide nanocarrier

Contributions of Overseas Chinese Merchants in South Seas to the Development of Shanghai's International Trade in Modern Times

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学术界 2019年第2期 217-232页

作者： zhang xiaobing zhang Guoyi Anhui Vocational Collage of City Management Shanghai University of International Business and Economics

Contributions of Overseas Chinese Merchants in South Seas to the Development of Shanghai's International Trade in Modern

关键词： Overseas Chinese Merchants in South Seas Shanghai International Trade

Finite density scaling laws of condensation phase transition in zero-range processes on scale-free networks

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Chinese Physics B 2020年第8期29卷 579-585页

作者： Guifeng Su Xiaowen Li xiaobing zhang Yi zhang Department of Physics Shanghai Normal UniversityShanghai 200234China School of Physics Nankai UniversityTianjin 300071China

The dynamics of zero-range processes on complex networks is expected to be influenced by the topological structure of underlying networks.A real space complete condensation phase transition in the stationary state may *** study the finite density effects of the condensation transition in both the stationary and dynamical zero-range processes on scale-free *** means of grand canonical ensemble method,we predict analytically the scaling laws of the average occupation number with respect to the finite density for the steady *** further explore the relaxation dynamics of the condensation phase *** applying the hierarchical evolution and scaling ansatz,a scaling law for the relaxation dynamics is *** Carlo simulations are performed and the predicted density scaling laws are nicely validated.

关键词： finite density scaling zero-range processes(ZRP) scale-free networks

Evaluation of Component Activities in C-Mn-Fe-Si with Model Self-SReM4

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Journal of Iron and Steel Research International 1998年第1期5卷 28-33页

作者： zhang xiaobing Jiang Guochang Ding Weizhong Xu Kuangdi Shanghai Enhanced Lab of Ferrometallurgy Shanghai University

A sub-regular solution model SELFSReM4 used to evaluate activities of the components in a homogeneous region of a quaternary system has been developed in Shanghai Enhanced Lab of Ferrometallurgy. This paper introduces the application of SELFSReM4 in evaluating activities of the components in C-Mn-Fe-Si system without SiC precipitation.

关键词： sub-regular solution model component activity C-Mn-Si-Fe alloy

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