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Defence Technology（防务技术） 2020年第4期16卷 747-752页

作者： Chun-yan zhu bao-ming Li National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyChina

The contact resistance between the armature and rails is an important indicator of the contact characteristics in electromagnetic *** the contact resistance depends not only on the contact state but also on the contact stress and temperature,there are some limitations in analyzing the contact characteristics using only the contact *** this paper,the contact characteristics of the augmented railgun are analyzed by the combination of contact resistance and sliding friction ***,the theoretical calculation model of the contact resistance and friction coefficient of the augmented electromagnetic railgun is *** the contact resistance and friction coefficient are calculated by the measured values of the muzzle voltage,rail current and armature ***,the contact characteristics are analyzed according to the features of the waveforms of the contact resistance and the friction coefficient,and the analysis conclusions are verified by experimental rail *** results showed that:the aluminum melt film gradually formed on the contact surface reduces the contact resistance and the friction coefficient;the wear and erosion of the armature cause deterioration of the contact state;after the transition,the reliability of the sliding contact between the armature and rails decreases,resulting in an increase in contact resistance.

关键词： Augmented railgun Contact resistance Friction coefficient Contact characteristics

脱落酸代谢及信号转导对胡萝卜CO2加富的响应分析

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核农学报 2025年第2期39卷 275-286页

作者：宋红霞高崇真朱伟龙路强宋甜月山西农业大学园艺学院

胡萝卜作为世界十大蔬菜之一，随着设施农业的发展实现了周年供应。增施CO2可提高胡萝卜产量和类胡萝卜素积累，而脱落酸（ABA）是调控植物生长和响应外界刺激的重要激素。为了探究胡萝卜ABA代谢和信号转导响应CO2加富的分子机制，本研... 详细信息

胡萝卜作为世界十大蔬菜之一，随着设施农业的发展实现了周年供应。增施CO2可提高胡萝卜产量和类胡萝卜素积累，而脱落酸（ABA）是调控植物生长和响应外界刺激的重要激素。为了探究胡萝卜ABA代谢和信号转导响应CO2加富的分子机制，本研究分析CO2加富与对照条件下ABA含量和9-顺式环氧类胡萝卜素双加氧酶（NCED）含量的变化；利用RNA-Seq分析CO2加富条件下脱落酸代谢和信号转导过程中参与的关键基因表达情况。结果发现，增施CO2抑制了ABA的合成，降低了酶含量；转录组分析共获得482个差异表达基因（DEGs），其中16个直接响应ABA代谢或与ABA信号转导相关，7个与ABA代谢相关，9个参与ABA信号通路，初步揭示了ABA信号和CO2感知之间的分子关联，ABA不仅高度响应CO2浓度变化，而且参与信号转导过程，调控生长发育。本研究结果为CO2加富条件下ABA积累机制和调控ABA信号转导机制探究提供了参考。

关键词：胡萝卜脱落酸 CO2加富信号转导

The regulatory sciences for stem cell-based medicinal products

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Frontiers of Medicine 2014年第2期8卷 190-200页

作者： bao-zhu Yuan JunzhiWang National Institutes for Food and Drug Control Beijing 100050 China

Over the past few years, several new achievements have been made from stem cell studies, many of which have moved up from preclinical stages to early, or from early to middle or late, stages thanks to relatively safe profile and preliminary evidence of effectiveness. Moreover, some stem cell-based products have been approved for marketing by different national regulatory authorities. However, many critical issues associated mainly with incomplete understanding of stem cell biology and the relevant risk factors, and lack of effective regulations still exist and need to be urgently addressed, especially in countries where establishment of appropriate regulatory system just commenced. More relevantly, the stem cell regulatory sciences need to be established or improved to more effectively evaluate quality, safety and efficacy of stem cell products, and for building up the appropriate regulatory framework. In this review, we summarize some new achievements in stem cell studies, especially the preclinical and clinical studies, the existing regulations, and the associated challenges, and we then propose some considerations for improving stem cell regulatory sciences with a goal of promoting the steadfast growth of the well-regulated stem cell therapies abreast of evolvement of stem cell sciences and technologies.

关键词： stem cell-based medicinal products (SCMPs) stem cell therapy (SCT) safety effectiveness standards guidelines regulatory science

On Real-rootedness of Independence Polynomials of Rooted Products of Graphs

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Acta Mathematicae Applicatae Sinica 2023年第4期39卷 854-867页

作者： Aria Ming-yue zhu bao-xuan zhu School of Mathematics and Statistics Jiangsu Normal UniversityXuzhou 221116China

An independent set in a graph G is a set of pairwise non-adjacent vertices. The independence polynomial of G is the polynomial AΣx^(|A|), where the sum is over all independent sets A of G. In 1987, Alavi,Malde, Schwenk and Erd os conjectured that the independence polynomial of any tree or forest is *** this unimodality conjecture has attracted many researchers’ attention, it is still open. Recently, Basit and Galvin even asked a much stronger question whether the independence polynomial of every tree is ordered log-concave. Note that if a polynomial has only negative real zeros then it is ordered log-concave and *** this paper, we observe real-rootedness of independence polynomials of rooted products of graphs. We find some trees whose rooted product preserves real-rootedness of independence polynomials. In consequence, starting from any graph whose independence polynomial has only real zeros, we can obtain an infinite family of graphs whose independence polynomials have only real zeros. In particular, applying it to trees or forests, we obtain that their independence polynomials are unimodal and ordered log-concave.

关键词： independence polynomials unimodality real zeros rooted products claw-free graphs

Novel dihydropyrazole derivatives linked with multi(hetero)aromatic ring:Synthesis and antibacterial activity

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Chinese Chemical Letters 2009年第4期20卷 427-430页

作者： Lin Shan Bai Yan Wang Xin Hua Liu Hai Liang zhu bao An song Key Laboratory of Anhui Educational Department Anhui University of Technology Maanshan 243002 China State Key Laboratory of Pharmaceutical Biotechnology Nanjing University Nanjing 210093 China Key Laboratory of Green Pesticide and Agriculture Bioengineering Ministry of Education Guizhou University Guiyang 550025 China

Eight novel heterocycle-substituted dihydropyrazole derivatives were synthesized and characterized by ESI-MS, ^1H NMR and ^13C NMR. All of the compounds have been screened for their antibacterial potential in vitro against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. The results show that compounds 9b, 9g and 9h displayed significant activity with MIC values in the range of 0.39-1.562 μlmL against B. subtilis.

关键词： Synthesis Multi(hetero)aromatic pyrazole Antibacterial activity

Deciphering Water Oxidation Catalysts: The Dominant Role of Surface Chemistry over Reconstruction Degree in Activity Promotion

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NANO-MICRO LETTERS 2025年第1期17卷 1-15页

作者： An, Li Li, Jianyi Sun, Yuanmiao zhu, Jiamin Seow, Justin zhu Yeow Zhang, Hong Zhang, Nan Xi, Pinxian Xu, Zhichuan J. Yan, Chun-Hua Lanzhou Univ Frontiers Sci Ctr Rare Isotopes Key Lab Nonferrous Met Chem & Resources Utilizat G State Key Lab Appl Organ ChemColl Chem & Chem Eng Lanzhou 730000 Peoples R China Nanyang Technol Univ Sch Mat Sci & Engn Singapore 639798 Singapore Chinese Acad Sci Fac Mat Sci & Energy Engn Shenzhen Inst Adv Technol Inst Technol Carbon Neutral Shenzhen 518055 Peoples R China Yunnan Univ Natl Ctr Int Res Photoelect & Energy Mat Electron Microscopy Ctr Sch Mat & EnergyKey Lab Electromagnet Mat & Devic Kunming 650091 Peoples R China baotou Res Inst Rare Earths State Key Lab Baiyunobo Rare Earth Resource Res & Baotou 014030 Peoples R China Peking Univ Beijing Natl Lab Mol Sci State Key Lab Rare Earth Mat Chem & Applicat PKU HKU Joint Lab Rare Earth Mat & Bioinorgan Chem Beijing 100871 Peoples R China

Demonstrate that the key factor to determine the activity of reconstructed surfaces is the surface chemistry, instead of reconstruction degree using the popular perovskite LaNi1-xFexO3 oxides as model *** content can influence both the surface reconstruction degree, the activation degree, and the activity of reconstructed *** oxygen evolution reaction activity of reconstructed catalysts is primarily governed by the chemistry of the reconstructed surface species. Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution reaction. The surface reconstruction has been widely observed in perovskite catalysts, and the reconstruction degree has been often correlated with the activity enhancement. Here, a systematic study on the roles of Fe substitution in activation of perovskite LaNiO3 is reported. The substituting Fe content influences both current change tendency and surface reconstruction degree. LaNi0.9Fe0.1O3 is found exhibiting a volcano-peak intrinsic activity in both pristine and reconstructed among all substituted perovskites in the LaNi1-xFexO3 (x = 0.00, 0.10, 0.25, 0.50, 0.75, 1.00) series. The reconstructed LaNi0.9Fe0.1O3 shows a higher intrinsic activity than most reported NiFe-based catalysts. Besides, density functional theory calculations reveal that Fe substitution can lower the O 2p level, which thus stabilize lattice oxygen in LaNi0.9Fe0.1O3 and ensure its long-term stability. Furthermore, it is vital interesting that activity of the reconstructed catalysts relied more on the surface chemistry rather than the reconstruction degree. The effect of Fe on the degree of surface reconstruction of the perovskite is decoupled from that on its activity enhancement after surface reconstruction. This finding showcases the importance to customize the surface chemistry of reconstructed catalysts for water oxidation.

关键词： Oxygen evolution reaction Perovskite oxides Doping Activation and reconstruction

Numerical Solution to Optimal Feedback Control by Dynamic Programming Approach:A Local Approximation Algorithm

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Journal of Systems Science & Complexity 2017年第4期30卷 782-802页

作者： GUO bao-zhu WU Tao-Tao Academy of Mathematics and Systems Science Chinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences

This paper considers optimal feedback control for a general continuous time finite-dimensional deterministic system with finite horizon cost functional. A practically feasible algorithm to calculate the numerical solution of the optimal feedback control by dynamic programming approach is developed. The highlights of this algorithm are: a) It is based on a convergent constructive algorithm for optimal feedback control law which was proposed by the authors before through an approximation for the viscosity solution of the time-space discretization scheme developed by dynamic programming method; b) The computation complexity is significantly reduced since only values of viscosity solution on some local cones around the optimal trajectory are calculated. Two numerical experiments are presented to illustrate the effectiveness and fastness of the algorithm.

关键词： Curse of dimensionality Hamilton-Jacobi-Bellman equation optimal feedback control upwind finite difference viscosity solutions

Novel C15 sesquiterpanes and their origin in different crude oils from the Pearl River Mouth Basin of China

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Science China Earth Sciences 2016年第8期59卷 1622-1632页

作者： bao JianPing CHEN XiWen zhu CuiShan Key Laboratory of Oil&Gas Resource and Exploration Technology Geochemistry DepartmentYangtze UniversityWuhan 430100China

In the saturate fractions of crude oils from the zhu1 and zhu2 depressions of the Pearl River Mouth Basin,two novel C_(15) sesquiterpanes have been detected except for drimanes and rearranged *** comparison with spectra and retention times in previous studies,they have been identified as 2,2,4α,7,8-pentamethyl-trans-decalin and 2,2,4α,7,8-pentamethyl-cis-decalin,respectively,which are related to the D/Eringsof18α(H)-and18β(H)-***15sesquiterpanesarerelativelyabundantincondensateoilsthathavehighPr/Phratiosandarerichinterrigenoustriterpanessuchasoleananeandbicadinanesfromthezhu2depression,butevidentlylowinlacustrineoilsthathavelowPr/***15sesquiterpanescouldberelatedtoterrigenousorganicmatterinorigina***,thereexistcompletelydifferentcorrelationsbetweentherelativeabundancesofdifferentC15sesquiterpanesthathavedifferentsourcesandthePr/Phratio,***,thenovelC15sesquiterpanesandcadinanethatindicateterrigenousinputarepositivelycorrelatedwiththePr/Phratio,butdrimanesandrearrangeddrimaneshavingmicrobialoriginarenegativelycorrelatedwiththePr/******15sesquiterpanesaremuchmoreabundantincarbonaceousmudstone(Pr/Ph=7.39)thanindarkmudstone(Pr/Ph=2.19)fromtheEnpingformation,***,theyarenotcommoninsapropeliclacustrinesourcerocks(Pr/Ph=2.29)***ition,butanoxicenvironmentduringdepositionanddiagenesismaybeaprerequisitefortheformationofnovelC15sesquiterpanes.

关键词： Sesquiterpanes Drimanes Cadinane Oleanane Bicadinanes Crude oils Pearl River Mouth Basin

Chemical behavior of organic compounds in the interface of water/dual-cation organobentonite

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Journal of Environmental Sciences 2002年第1期14卷 12-19页

作者： CHEN bao liang zhu Li zhong Department of Environmental Science Zhejiang UniversityHangzhou 310028China.

The sorption behavior of polar or ionizable organic compounds, such as p nitrophenol, phenol and aniline, in the water/organobentonite systems is investigated. Both adsorption and partition occur to the sorption of organic compounds to dual cation organobentonites. The separate contributions of adsorption and partition to the total sorption of organic compounds to dual cation organobentonites are analyzed mathematically in the first time. The factors to the contributions are also discussed. The results indicated that the contribution of adsorption and partition is related to the composition and ratio of dual cation surfactants exchanging onto the bentonite. The sorption of organic compounds to dual cation organobentonite is dominated by adsorption at low concentrations and by partition at high concentrations, making the organobentonites powerful sorbents for organic contaminants over wide range of concentrations.

关键词： dual-cation organobentonite p-nitrophenol phenol aniline sorption behavior

Partition of polycyclic aromatic hydrocarbons on organoben-tonites from water

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Journal of Environmental Sciences 2001年第2期13卷 129-136页

作者： CHEN bao-liang zhu Li-zhong Department of Environmental Science Zhejiang UniversityHangzhou 310028China

A series of organobentonites synthesized by exchanging organic ration such as dodecyltri-methylammonium ( DTMA), benzyldimethyltetradecylammonium (BDTDA), cetyltrimethyl-ammonium (CTMA), octodeyltrimethylammonium (OTMA) on bentonite The optimal condition, properties and mechanisms for the organobentonites to sorb phenanthrene, anthracene, naphthalene, acenaphthene in water were investigated in detail. The partition behavior was determined for four polycyclic aromatic hydrocarbons (PAHs), such as naphthalene, phenanthrene, anthracene and acenaphthene, from water to a series of organobentortites. The interlayer spacings and organic carbon contents of organobentonites, removal rate and sorption capacities for organobentonites to treat phenanthrene, anthracene, naphthalene, acenaphthene were correlated to the length of alkyl chains and the amounts of ration surfactant exchanged on the bentonite. Phenanthrene, anthracene, naphthalene, and acenaphthene sorption to organobentonites were characterized by linear isotherms, indicating solute partition between water and the organic phase composed of the large alkyl functional groups of quaternary ammonium rations. PAHs distribution coefficients (K-d) between organobentonites and water were proportional to the organic carbon contents of organobentonites. However, the partition coefficients ( K-oc) were nearly constants for PAHs in the system of organobentonite-water. The K-ocx of phenanthrene, anthracene, naphthalene, acenaphthene were 2.621 x 10(5), 2.106 x 10(5), 2.247 x 10(4), 5.085 x 10(4), respectively. The means K-oc values on the organobentonites are about ten to twenty times larger than the values on the soils/sediments, what is significant prerequisite for organobentonite to apply to remediation of pollution soil and groundwater. The sorption mechanism was also evaluated from octanol-water partition coefficients and aqueous solubility of PAHs. The correlations between 1gK(oc) and 1gK(ow), 1gK(oc) and 1gS for PAHs in th

关键词： organobentonites polycyclic aromatic hydrycarbons partition