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高温下HMX热分解反应分子动力学模拟

原子与分子物理学报 2025年第2期42卷 105-110页

作者：陈芳贾方硕陈瑶李天浩郭国琦董羚中北大学化学与化工学院太原030051

本文采用ReaxFF-lg反应分子动力学方法研究了奥克托金(HMX)在六种不同温度下的初始反应热分解过程,验证了ReaxFF-lg势函数对HMX体系的适用性,计算了不同温度下HMX体系势能、总物种演化趋势、初始反应产物以及指前因子和活化能.结果表明,... 详细信息

本文采用ReaxFF-lg反应分子动力学方法研究了奥克托金(HMX)在六种不同温度下的初始反应热分解过程,验证了ReaxFF-lg势函数对HMX体系的适用性,计算了不同温度下HMX体系势能、总物种演化趋势、初始反应产物以及指前因子和活化能.结果表明,HMX热分解过程主要有三种初始分解机理:N-NO_(2)键的断裂,HONO的解离和主环上C-N键的断裂,计算得到的初始分解阶段活化能Ea和指前因子ln(A),与实验值相吻合.

关键词： HMX 反应分子动力学(RMD) ReaxFF-lg 热分解温度

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Three-dimensional fluorescence spectral characterization of soil dissolved organic matters in the fluctuating water-level zone of Kai County,Three Gorges Reservoir

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Frontiers of Environmental Science & Engineering 2011年第3期5卷 426-434页

作者： fang fang yan yanG Jinsong guo Hong ZHOU Chuan FU Zhe LI Key Laboratory of Three Gorges Reservoir Region’s Eco-Environment of Ministry of Education Chongqing UniversityChongqing 400045China

Three-dimensional fluorescence spectroscopy was used to investigate the fluorescent properties of soil dissolved organic matter(DOM)in the water-levelfluctuation zone(WLFZ)of Kai County,Three Gorges Reservoir(TGR).Most of the soil DOM analyzed in this study was found to contain four fluorescence *** A and C represent humic-like fluorescence,whereas peaks B and D represent tryptophan-like *** E and F,which represent tyrosine-like fluorescence,only appeared in certain *** humus was the main source of DOM in soil,and higher concentration of soil DOM was found in the exposed soil than submerged *** to the peaks A and B,the fluorescence intensities of peaks C and D were strongly influenced by the fluctuating water *** of fluorescence intensities of different peaks in soil DOM showed that WLFZ soil was not contaminated *** DOM contained at least two types of humic-like fluorescence groups and two types of protein-like fluorescence *** proportion of the content of peak A in soil organic matter was quite *** soil DOM in exposed soil had relatively high humification and aromaticity,and periodic submerging and exposure of soil had an impact on the humification of soil DOM.

关键词： water-level-fluctuation zone(WLFZ) soil dissolved organic matter(DOM) three-dimensional fluorescence spectra

Diastereoselective Synthesis of 1,10-Dihydropyrrolo [ 1,2-a] [1,10]phenanthroline Derivatives via 1,3-Dipolar Cycloaddition Reaction

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Chemical Research in Chinese Universities 2013年第6期29卷 1089-1093页

作者： LIU Zhen-ming fang Jun yan Chao-guo Analysis and Test Center Yangzhou University Yangzhou 225002 P.R.China College of Chemistry & Chemical Engineering Yangzhou University Yangzhou 225002 P.R.China

The functionalized 1,10-dihydropyrrolo[1,2-a][1,10]phenanthroline derivatives were synthesized in good yields and with high diastereoselectivity by 1,3-dipolar cycloaddition reactions of N-phenacylphenanthrolinium bromides or N-ethoxycarbonylmethylene phenanthrolinium bromide with various nitrostyrenes in acetonitrile at room temperature in the presence of triethvlamine,

关键词： Pyridinium ylide Phenanthroline Pyrrolo[1,2-a]phenanthroline 1,3-Dipolar cycloaddition Diastereoselectivity

Gene engineering in swine for agriculture

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Journal of Integrative Agriculture 2017年第12期16卷 2792-2804页

作者： WANG yan-fang HUANG Jiao-jiao ZHAO Jian-guo Institute of Animal Science Chinese Academy of Agricultural Sciences Beijing 100193 P.R. China Institute of Zoology Chinese Academy of Sciences Beijing 100101 P.R.China University of Chinese Academy of Sciences Beijing 100049 P.R. China

Domestic pigs are the second most important source of meat world-wide, and the genetic improvement of economic traits, such as meat production, growth, and disease resistance, is a critical point for efficient production in pigs. Through conventional breeding and selection programs in pigs, which are painstakingly slow processes, some economic traits, such as growth and backfat, have been greatly improved over the past several decades. However, the improvement of many polygenetic traits is still very slow and challenging to be improved by conventional breeding strategies. The development of reproductive knowledge and a variety of techniques, including foreign gene transfer strategies, somatic cell nuclear transfer（SCNT） and particularly, recently developed nuclease-mediated genome editing tools, has provided efficient ways to produce genetically modified（GM） pigs for the dramatic improvement of economic traits. In this review, we briefly discuss the progress of genomic markers used in pig breeding program, trace the history of genetic engineering, mainly focusing on the progress of recently developed genome editing tools, and summarize the GM pigs which have been generated to aim at the agricultural purposes. We also discuss the specific challenges facing application of gene engineering in pig breeding, and future prospects.

关键词： gene engineering genome editing pig agricultural application

Synthesis and characterization of spinel Li_(1.05)Cr_(0.1)Mn_(1.9)O_(4-z)F_z as cathode materials for lithium-ion batteries

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International Journal of Minerals,Metallurgy and Materials 2010年第2期17卷 220-224页

作者： yan-bin Chen yang Hu fang Lian Qing-guo Liu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Beijng Easpring Material Technology Co. Ltd. Beijing 100044 China Beijing General Research Institute of Mining ＆ Metallurgy Beijing 100044 China

Samples with the nominal stoichiometry Li1.05Cr0.1Mn1.9O4-zFz（z=0,0.05,0.1,0.15,and 0.2） were synthesized via the solid-state reaction method and characterized by X-ray powder diffraction（XRD）,scanning electron microscopy（SEM）,galvanostatic charge/discharge, and slow rate cyclic voltammetry（SSCV） *** results show that the pure spinel phase indexed to Fd3m can be obtained when z=0, 0.05,and *** substitution of F for O with z≤0.1 contributes to the increase of initial capacity compared with Li1.05Cr0.1Mn1.9O4 spinels. However,when the F-dopant content is designed to be 0.15 and 0.2,the Li1.05Cr0.1Mn1.9O4-zFZ samples deliver relatively low capacity and poor cycling properties at 55℃.

关键词： lithium-ion batteries cathode materials doping electrochemical properties

Effect of Coating on Instantaneous Interfacial Heat Transfer During Near-Rapid Solidification

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Journal of Iron and Steel Research International 2011年第11期18卷 67-73页

作者： ZHANG Wei YU yan fang Yuan LI Jian-guo School of Materials Science and Engineering Shanghai Jiaotong University Shanghai 200240 China Baosteel Research Institute Baosteel Co Ltd Shanghai 201900 China

For many rapid or near-rapid solidification processes, the interracial heat transfer between the melt and the substrate is a key issue on the cooling and solidification rate of castings. For the purpose of controlling and adjusting of the interfacial thermal resistance, the effects of C/BN, Zn and organic coatings on the instantaneous interracial heat flux and the solidified structure of AISI304 stainless steel solidification on copper substrate have been investiga- ted by using an experimental simulator. The results show that C/BN coatings can improve the uniformity of heat flux and solidified structure; Zn coating can increase the heat flux and solidification rate in the growth stage of the solidified shell; organic coating will decrease the heat flux and the solidification rate and make re-melted structure on the surface of the solidified shell.

关键词： near rapid solidification interracial heat transfer coating

Adaptive fuzzy integral sliding mode velocity control for the cutting system of a trench cutter

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Frontiers of Information Technology & Electronic Engineering 2016年第1期17卷 55-66页

作者： Qi-yan TIAN Jian-hua WEI Jin-hui fang Kai guo State Key Laboratory of Fluid Power&Mechatronic Systems Zhejiang UniversityHangzhou 310027China

This paper presents a velocity controller for the cutting system of a trench cutter(TC). The cutting velocity of a cutting system is affected by the unknown load characteristics of rock and soil. In addition, geological conditions vary with time. Due to the complex load characteristics of rock and soil, the cutting load torque of a cutter is related to the geological conditions and the feeding velocity of the cutter. Moreover, a cutter's dynamic model is subjected to uncertainties with unknown effects on its function. In this study, to deal with the particular characteristics of a cutting system, a novel adaptive fuzzy integral sliding mode control(AFISMC) is designed for controlling cutting velocity. The model combines the robust characteristics of an integral sliding mode controller with the adaptive adjusting characteristics of an adaptive fuzzy controller. The AFISMC cutting velocity controller is synthesized using the backstepping technique. The stability of the whole system including the fuzzy inference system, integral sliding mode controller, and the cutting system is proven using the Lyapunov theory. Experiments have been conducted on a TC test bench with the AFISMC under different operating conditions. The experimental results demonstrate that the proposed AFISMC cutting velocity controller gives a superior and robust velocity tracking performance.

关键词： Cutting system, Electro-hydraulic system, Cutting velocity control, Adaptive fuzzy integral sliding mode control

5291例儿科不同疾病患儿中肺炎支原体感染情况的分析

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中国当代儿科杂志 2005年第6期7卷 549-550页

作者：古丽娜.沙丁郭艳芳米热婉古丽新疆医科大学第一附属医院儿科新疆乌鲁木齐830054 新疆拜城县人民医院新疆拜城842300

为了解我院儿科不同疾病患儿中肺炎支原体（Mycoplasma pneumoniae,MP）感染的总体情况以及感染率与季节、年龄的相关性,对近3年间在我院儿科门诊就诊和住院的不同疾病患儿进行了MP血清学检测,结果报告如下.

关键词：肺炎支原体不同疾病感染情况患儿儿科血清学检测门诊就诊结果报告感染率

Three-dimensional flower-like SnS_(2)-supported bimetallic zeolite imidazole compound with enhanced electrocatalytic activity for methanol oxidation

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Frontiers of Materials Science 2021年第1期15卷 166-175页

作者： Jinxing WANG fang YU Zhenzhen guo Lei yan Xianbao WANG Key Laboratory for Green Preparation and Application of Functional Materials(Ministry of Education) Hubei Key Laboratory of Polymer MaterialsSchool of Materials Science and EngineeringHubei UniversityWuhan 430062China

Proton exchange membrane fuel cells(PEMFCs)are considered as one of the most effective technologies to resolve environmental problems and energy crisis for future automotive applications[1-4].The direct methanol fuel cell(DMFC)[5-6]is a new type of PEMFC using methanol as fuel[7].Because of its higher energy density and conversion efficiency,methanol can be used as direct fuel at a relatively lower operating temperature[8]with portable great potential in equipment and transportation ***,developing DMFCs that use methanol aqueous solution or steam methanol as fuel is a good choice to solve energy problems[9].

关键词： methanol zeolite compound