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Structure and stability of boron nitride cages

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Chinese Science bulletin 2003年第11期48卷 1102-1107页

作者： WU Haishun xu Xiaohong JIAO Haijun ZHANG fuqiang JIA Jianfeng Department of Chemistry Shanxi Normal UniversityDepartment of Chemistry Shanxi Normal UniversityDepartment of Chemistry Shanxi Normal UniversityDepartment of Chemistry Shanxi Normal UniversityDepartment of Chemistry Shanxi Normal University Linfen 041004 China Linfen 041004 China Linfen 041004 China Linfen 041004 China Linfen 041004 China

The structure and energy of boron nitrides, (bN)n (n = 10—41), have been investigated theoretically. The most stable cages have been constructed on the basis of a simple design principle, and the predicated stability has been validated at the b3LYP/6-31G* level of theory. Among these, the Th symmetrical (bN)12 cluster has been confirmed to be the most stable cage on the basis of the calculated disproportation energy and binding energy per bN unit.

关键词：硼氮化合物稳定性结构 bN 分解能结合能

Experimental Investigation on Ignition and Lean blow-out Performance of a Multi-sector Centrally Staged Combustor

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Journal of Thermal Science 2014年第5期23卷 480-485页

作者： LIU fuqiang ZHANG Kaiyu MU Yong LIU Cunxi YANG Jinhu xu Gang ZHU Junqiang Institute of Engineering Thermophysics Chinese Academy of Science

Improvement on extinction and pollution emission have become one of the most prominent research topics in gas *** is widely recognized that the fuel/air mixture distribution in the recirculation zone is a critical factor in improving lean blow-out(LbO) and *** paper proposed a new low emission scheme with fuel staged centrally and hybrid injector to improve flameout and emission.A relative small amount of fuel enters into central pilot airblast atomizer burner and then atomized by inner swirl *** remaining majority of fuel is directly injected into vane channels of the primary swirler through a series of holes located on the sidewall of the main *** pilot stage is fueled under ignition and lean flameout *** uniformity of fuel/air mixture distribution in the primary zone of the new design decreases NOX emission,meanwhile the fuel air mixture in pilot recirculation zone is locally rich to improve flameout and *** investigation was conducted to compare the new scheme with baseline design of dual-swirler in terms of LbO and ignition characteristics under the same condition in a multi-sector *** is found that the fuel-air ratio of ignition limit and LbO decrease with the reference velocity *** experimental results also show that the new scheme successfully improve lean blow-out and broaden the operation range of the *** experimental results indicated that the centrally staged scheme can widen the operation boundary of the combustor and can provide guidance for design and optimization of combustion chamber.

关键词： Ignition Lean blow-out Staged combustor Pilot stage Fuel air ratio

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胶结回收沥青混合料地聚物的力学性能研究

重庆理工大学学报（自然科学） 2024年第4期38卷 108-115页

作者：刘富强郭伟东陈二忠徐子龙曹天白雪晴河北大学建筑工程学院河北保定071002 长安大学公路学院西安710064 西安公路研究院有限公司西安710065 杭州科技职业技术学院城市建设学院杭州311402 榆林学院能源工程学院陕西榆林719000

为缓解石油沥青资源匮乏问题,实现废弃回收沥青混合料(reclaimed asphalt pavement,RAP)高效资源化利用,选择粉煤灰、矿渣粉、碱激发剂和其他助剂研发一种新型胶结RAP的地聚物胶结材料(S-F Geopolymer),通过抗压和抗折试验对S-F Geopoly... 详细信息

为缓解石油沥青资源匮乏问题,实现废弃回收沥青混合料(reclaimed asphalt pavement,RAP)高效资源化利用,选择粉煤灰、矿渣粉、碱激发剂和其他助剂研发一种新型胶结RAP的地聚物胶结材料(S-F Geopolymer),通过抗压和抗折试验对S-F Geopolymer的基本力学性能和强度形成机理进行研究。结果表明:S-F Geopolymer的最佳配方为m(粉煤灰)∶m(矿渣粉)=2∶1,碱浓度、模数和水胶比分别为0.05、1.2和0.3。在最佳配方下,S-F Geopolymer具有良好的抗压和抗折强度。3 d抗压和抗折强度分别为42.33和4.28 MPa,7 d抗压和抗折强度分别为55.63和5.73 MPa,28 d抗压和抗折强度分别为72.75和7.42 MPa。研究成果可为地聚物材料胶结RAP的理论研究和工程应用提供参考。

关键词：胶结料回收沥青混合料地聚物力学性能强度机理

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超级电容器用电极材料研究进展

当代化工研究 2024年第7期 29-32页

作者：肖富强林广常乐徐强舒钞成都宏科电子科技有限公司四川610100

超级电容器具有的高能量密度、高功率密度、使用稳定性好、环境友好等特点,使其在储能领域得到了广泛的研究与应用。文章介绍了超级电容器的分类和储能机理,并重点阐述了碳基材料、金属化合物、导电聚合物三类常用电极材料的研究进展,最... 详细信息

超级电容器具有的高能量密度、高功率密度、使用稳定性好、环境友好等特点,使其在储能领域得到了广泛的研究与应用。文章介绍了超级电容器的分类和储能机理,并重点阐述了碳基材料、金属化合物、导电聚合物三类常用电极材料的研究进展,最后,从掺杂复合与结构设计两个方面对超级电容器电极材料的发展方向进行了展望。

关键词：超级电容器电极材料碳材料金属化合物导电聚合物

Lean blowout characteristics of spray flame in a multi-swirl staged combustor under different fuel decreasing rates

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Chinese Journal of Aeronautics 2022年第12期35卷 130-143页

作者： Qianpeng ZHAO Jinhu YANG Cunxi LIU fuqiang LIU Shaolin WANG Yong MU Gang xu Junqiang ZHU Laboratory of Light-Duty Gas-Turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Innovation Academy for Light-duty Gas Turbine Beijing 100190China

Lean blow Out(LbO)poses a significant safety hazard when occurring in *** the lower stability limits of gas turbine combustors and the characteristics of spray flame close to LbO are imperative for safe *** objective of this work is to evaluate the effects of fuel decreasing rates and pressure drops of the injector on LbO performances in a multiswirl staged combustor equipped with an airblast injector.A set of hardware and control system was developed to realize a user-defined fuel supply ***-speed imaging was applied to record complete LbO processes under the conditions of linear fuel reduction and stable *** Image Velocimetry(PIV)and Planar Mie(PMie)scattering were used to acquire the flow fields and spray fields under non-reacting *** results have shown that LbO limits extend to leaner conditions as the pressure drop of the injector *** an increase of the fuel decreasing rate,the exhaust temperature before flame extinction increases,and the LbO Fuel-to-Air-Ratio(FAR)*** time evolution of the integral CH*intensity conforms to a linear function during the LbO *** Orthogonal Decomposition(POD)was used to analyze the dynamic characteristics of lean-burn *** different fuel decreasing rates and pressure drops of the injector,flames close to LbO present similar modal spatial distributions,alternately appearing axial,radial,high-order axial,and high-order radial oscillations.

关键词： blowout Combustors Flame dynamics High-speed imaging POD

石英脉型钨多金属矿床的扇状成矿实例及找矿模型

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矿床地质 2024年第3期43卷 613-628页

作者：方贵聪王登红黄长帅杨富强许以明冯佐海李学彪曾强严长华广西隐伏金属矿产勘查重点实验室桂林理工大学广西桂林541004 有色金属矿产勘查与资源高效利用省部共建协同创新中心桂林理工大学广西桂林541004 中国地质科学院矿产资源研究所北京100037 中国有色桂林矿产地质研究院有限公司广西桂林541004 广西壮族自治区地球物理勘察院广西柳州545005 湖南省矿产资源调查所湖南长沙410014 江西大吉山钨业有限公司江西全南341801 湖南省水文地质环境地质调查监测所湖南长沙410131

石英脉型钨矿床是中国数量最多的钨矿床类型,但保有储量消耗迅速,迫切需要创新找矿模型,指导找矿突破。文章结合二十余年的找矿实践,通过详细分析扇状成矿矿床实例,构建了石英脉型钨矿床新的找矿模型。该模型强调赋矿裂隙为岩浆动力成因... 详细信息

石英脉型钨矿床是中国数量最多的钨矿床类型,但保有储量消耗迅速,迫切需要创新找矿模型,指导找矿突破。文章结合二十余年的找矿实践,通过详细分析扇状成矿矿床实例,构建了石英脉型钨矿床新的找矿模型。该模型强调赋矿裂隙为岩浆动力成因,在花岗岩体顶部呈扇状分布型式,岩浆期后热液恰在裂隙张开时充填其中而形成扇状成矿系统;提出“就岩找矿”、“就矿找矿”、“就矿找岩”的地质、地球化学和地球物理标志,指导矿床尺度的勘查工程部署。截至目前,该模型已在广东禾尚田钨锡矿床、广西珊瑚钨锡矿床、广西社垌钨钼矿床、江西盘古山钨铋矿床等获得了验证,找矿成效显著。

关键词：扇状成矿成矿规律找矿模型花岗岩石英脉型钨矿床

维普期刊数据库博看期刊

Detection and characterization of diverse alpha-and betacoronaviruses from bats in China

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Virologica Sinica 2016年第1期31卷 69-77页

作者： Lin xu fuqiang Zhang Weihong Yang Tinglei jiang Guanjun Lu biao He Xingyu Li Tingsong Hu Gang Chen Yun Feng Yuzhen Zhang Quanshui Fan jiang Feng Hailin Zhang Changchun Tu Military Veterinary Institute Academy of Military Medical SciencesChangchun 130122China Center for Disease Control and Prevention of Chengdu Military Region Kunming 650118China Yunnan Institute of Endemic Diseases Control and Prevention Dali 671000China School of Urban and Environmental Sciences Northeast Normal UniversityChangchun 130024China jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses Yangzhou 225009China

bats have been implicated as important reservoir hosts of alpha- and betacoronaviruses. In this study, diverse coronaviruses(CoVs) were detected in 50 of 951(positive rate 5.3%) intestinal specimens of eight bat species collected in four provinces and the Tibet Autonomous Region of China by pan-coronavirus RT-PCR screening. based on 400-nt RNA-dependent RNA polymerase(Rd RP) sequence analysis, eight belonged to genus Alphacoronavirus and 42 to *** the 50 positive specimens, thirteen gave rise to CoV full-length Rd RP gene amplification for further sequence comparison, of which three divergent sequences(two from a unreported province) were subjected to full genome sequencing. Two complete genomes of betacoronaviruses(JTMC15 and JPDb144) and one nearly-complete genome of alphacoronavirus(JTAC2) were sequenced and their genomic organization predicted. The present study has identified additional numbers of genetically diverse bat-borne coronaviruses with a wide distribution in China. Two new species of bat CoV, identified through sequence comparison and phylogenetic analysis, are proposed.

关键词： bats Alphacoronavirus betacoronavirus diversity

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道砟清筛机铸钢件质量改进

中国铸造装备与技术 2024年第2期59卷 42-45页

作者：贾旭吕昌略于小康李富强中车戚墅堰机车车辆工艺研究所有限公司江苏常州213025 江苏朗锐茂达铸造有限公司江苏江阴214445

介绍了道碴清筛机挖掘链铸钢件的失效情况,重点分析了失效件的断口形貌、力学性能、金相组织等,并通过对铸造生产过程进行调查分析,确定了失效的具体原因。制定了工艺改进方案,并对试验结果进行验证,各项技术指标均优于技术要求,有效提... 详细信息

介绍了道碴清筛机挖掘链铸钢件的失效情况,重点分析了失效件的断口形貌、力学性能、金相组织等,并通过对铸造生产过程进行调查分析,确定了失效的具体原因。制定了工艺改进方案,并对试验结果进行验证,各项技术指标均优于技术要求,有效提升了产品质量。

关键词：铸钢件失效分析工艺改进

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行星架铸件成型数值模拟及缺陷精准调控

铸造技术 2024年第4期45卷 388-394页

作者：陈烜徐哲刘琨蒋崴薛雨付珂赵永柱吕复强陈正常熟天地煤机装备有限公司江苏常熟215500 中国矿业大学材料与物理学院江苏徐州221008

行星架是采煤机齿轮传动系统中承受转矩、动载的关键传动件,使用中常多发裂纹缺陷而导致报废。基于此,针对采煤机齿轮传动用行星架的铸造工艺方案,利用ProCAST软件研究行星架铸件在充型和凝固过程中的温度场、速度场、凝固固相率及缩松... 详细信息

行星架是采煤机齿轮传动系统中承受转矩、动载的关键传动件,使用中常多发裂纹缺陷而导致报废。基于此,针对采煤机齿轮传动用行星架的铸造工艺方案,利用ProCAST软件研究行星架铸件在充型和凝固过程中的温度场、速度场、凝固固相率及缩松缩孔分布等模拟结果,对铸造方案进行了优化。结果表明,添加明冒口和冷铁后,行星架的缩松缩孔等缺陷得到了有效控制,行星架侧板部分缺陷减少57%以上,柱状部分缺陷完全避免,有效指导了煤机齿轮传动用行星架缩松类缺陷的防治,进而从根本上解决多发裂纹的问题。

关键词： ProCAST 行星架数值模拟铸造缺陷