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Journal of Materials Science & Technology 2012年第11期28卷 992-998页

作者： junhua gao Lin Zhang Jinquan Xiao Jun Gong Chao Sun Lishi Wen State Key Laboratory for Corrosion and Protection Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

The effects of an external magnetic field originating from two solenoid coils on the magnetic field configuration, plasma state of a dual unbalanced magnetron sputter system and the structure of nanocrystalline Si films were examined. Numerical simulations of the magnetic field configuration showed that increasing the coil current significantly changed the magnetic field distribution between the substrate and targets. The saturated ion current density Ji in the substrate position measured by using a circular flat probe increased from 0.18 to 0.55 mA/cm2 with the coil current ranging from 0 to 6 A. X-ray diffraction and Raman results revealed that increasing the ion density near the substrate would benefit crystallization of films and the preferential growth along [lI1] orientation. From analysis of the surface morphology and the microstructure of Si films grown under different plasma conditions, it is found that with increasing the Ji, the surface of the film was smoothed and the alteration in the surface roughness was mainly correlated to the localized surface diffusion of the deposited species and the crystallization behavior of the films.

关键词： Nanocrystalline silicon Thin film Solenoid coil MF magnetron sputtering

Preparation and Characterization of High Infrared Emissivity Mn-doped NCO Spinel Composites

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Journal of Wuhan University of Technology(Materials Science) 2017年第6期32卷 1265-1270页

作者：邹隽 DONG Shurong gao junhua WANG Hongfu 程旭东 State Key Laboratory of A-dvanced Technology for Materials Synthesis and Processing WuhanUniversity of Technology Wuhan 430070China College of Mechanical and Power Engineering China Three Gorges University Yichang 443002 China School of Mechanical Engineering North University of China Taiyuan 030051 China

NiCr2O4（NCO）spinel composites with different Mn/Ni atomic ratios（Mn/Ni=0.05,0.10,0.15,and 0.20）were synthesized via solid state reaction *** compositions and microstructure of samples were characterized by X-ray diffraction（XRD）and X-ray photoelectron spectroscopy（XPS）.The TG-DSC curves showed that the appropriate baking temperature for Mn-doped NCO spinel preparation was approximately 1 320℃.X-ray diffraction patterns exhibited the formation of NCO spinel with Fd-3m space *** state of the Mn ions was determined from 2p and 3s X-ray photoelectron *** ions were mostly in divalent and trivalent states,and the ratio of Mn^2＋/Mn^3＋was *** transform infrared spectroscopy（FTIR）was used to analyze the spectral emissivity of Mn doped NCO *** was revealed that the infrared emissivity of Mn-doped NCO spinel in 1.8-5μm could be significantly enhanced with increasing content of Mn^2＋,reaching as high as ***-doped NCO spinel showed excellent radiation performance and good prospect in high emissivity applications in the temperature range of 800-1 200℃.

关键词： NCO infrared emissivity Mn doped spinel XPS

Milling Research and Tool Selection Design of SiC14Cu4Mg0.5Si based on Aluminium Matrix 2A14

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Journal of Wuhan University of Technology(Materials Science) 2016年第6期31卷 1377-1380页

作者：王兴文祝锡晶 gao junhua ZHENG Zhizhen WANG Huajun School of Mechanical and Power Engineering North University of China Taiyuan 030051 China School of Materials Science and Engineering Wuhan University of Technology Wuhan 430070 China

The selection of milling tools for Si C14Cu4Mg0.5Si based on Aluminium matrix 2A14 was analyzed, and the factors that affect the efficiency of the milling were discussed. The Si C14Cu4Mg0.5Si was designed for use on the moon landing vehicle or missile wings, but the hardness of aluminium-silicon carbide composite material was very high, much higher than the general hardness of cemented carbide, which will bring many difficulties in the aluminium-silicon carbide composite material processing. The chemical compositions of Si C14Cu4Mg0.5Si were analyzed. A new selected indexable cutter was designed to mill Si C14Cu4Mg0.5Si. The structure design of milling cutter was different from the conventional milling cutter, breaking the previous limitations to a certain extent, pioneering the idea. The tool material wear was detected by experiments. The mechanical and physical properties of Si C14Cu4Mg0.5Si were also tested. Si C14Cu4Mg0.5Si exhibited different surface quality characteristics under different milling tools.

关键词： aluminium matrix silicon carbide milling surface quality Si C14Cu4Mg0 5Si milling tool

Synthesis and characterization of BZSM-5 and its catalytic performance in the methanol to hydrocarbons reaction

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Chinese Journal of Chemical Engineering 2021年第7期34卷 196-203页

作者： junhua gao Keming Ji Hao Zhou Jiayao Xun Zenghou Liu Kan Zhang Ping Liu State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China

Five kinds of BZSM-5 molecular sieve with different Si/B ratio and a SiZSM-5 molecular sieve were prepared by hydrothermal synthesis method followed by acid exchange and *** samples were characterized by XRD,SEM,FT-IR,ICP,low temperature N_(2) physical adsorption and desorption,NH3-TPD and *** catalytic performance in the reaction of methanol to hydrocarbons was evaluated in the fixed bed *** with SiZSM-5,the amount and strength of Bronsted(B)acid were enhanced by introducing skeleton boron and the activity of the catalyst was greatly *** characterization and evaluation results indicated that the BZSM-5 catalyst synthesized from the gel of SiO_(2)/B2 O320 with Si/B ratio 74.48 had modest acidity strength,acid amount of 0.18 mmol NH3·g^(-1) and large mesopore volume of 0.23 cm3·g^(-1).The B acid ratio was higher and the acid strength of BZSM-5 was weaker than that of AIZSM-5,which could inhibit the deep coke formation and increase the activity stability.B-2 had the best lifetime which could reach 672 h under the same evaluation reaction conditions,due to the best matching of moderate acidity and good diffusion properties.

关键词： ZSM-5 Catalysis Methanol Hydrocarbons

The study of methanol aromatization on transition metal modified ZSM-5 catalyst

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Chinese Journal of Chemical Engineering 2018年第9期26卷 1949-1953页

作者： Keming Ji Jiayao Xun Ping Liu Qingwen Song junhua gao Kan Zhang Jingyuan Li State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences

In this article, transition metals of Cu, La and Zn were used as adjuvant to prepare modified HZSM-5 by impregnation method. The catalysts were characterized by XRD, BET, NH_3-TPD and Py-IR to reveal the microstructure and acid property. The catalysis performances of methanol aromatization of catalysts were investigated in a fixed-bed reactor. The results show that the strength and distribution of acid center of these catalysts are significantly influenced by the species of transition metal. There are more mediate strong Lewis acid center in Zn modified HZSM-5 catalyst and therefore exhibits higher selectivity to aromatic, benzene, toluene and xylenes in the MTA reaction..

关键词： Aromatization ZSM-5 Metal modified

Effects of nanoparticle structural features on the light-matter interactions in nanocermet layers and cermet-based solar absorbers

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Journal of Materiomics 2021年第5期7卷 1103-1111页

作者： Xiaoyu Wang Houjin He junhua gao Haibo Hu Shiwei Tang Xiaoyun Li Xiuhong Li Hongtao Cao Ningbo Institute of Materials Technology&Engineering Chinese Academy of SciencesNingbo 315201China School of Physical Science and Technology Ningbo UniversityNingbo 315211China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China

Metallic nanoparticle(NP)/ceramic composite cermets present desirable broadband absorption of the solar spectrum and thus are the preferred material scheme for constructing cermet-based solar ***,the effects of fine nanoparticle structural features on the light-matter interactions in nanocermet layers and corresponding cermet-based solar absorbers are still not well clear until ***,we report a systematical investigation on the effects of W(tungsten)nanoparticle sizes,its concentrations and configurations in an alumina matrix on the optical responses of WeAl_(2)O_(3) nanocermet layers and a solar absorber with double-cermet *** is found that to possess admirable light absorption features at high temperatures,it is better to maintain the fine particle size of less than 10 nm,isolated states and suitable separations between them for WeAl_(2)O_(3) ***,the dominated intrinsic absorption of W NPs,their plasmonic excitation and coupling effects among each other all contribute significantly to the broadband optical performance of the cermet layers and the whole *** importantly,this study demonstrates a valuable criterion for maintaining optical performances of nanocermet layers and cermet-based solar absorbers under heating and thus their thermal robustness.

关键词： Nanocermet Solar absorbers Tungsten Plasmonic interaction Thermal stability

甲醇发动机与汽油发动机瞬态排放特性的对比研究

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汽车工程 2011年第9期33卷 753-756页

作者：尹超高俊华尧命发天津大学内燃机国家重点实验室天津300072 中国汽车技术研究中心天津300162

将一台电控多点喷射式汽油发动机改造为燃用甲醇燃料的甲醇发动机,并对甲醇发动机与原汽油发动机的瞬态排放特性进行了对比研究,分别检测了三效催化转化器后的常规污染物(CO、THC、NOx)和非常规污染物(甲醛、乙醛、甲醇、乙醇、氨)的排... 详细信息

将一台电控多点喷射式汽油发动机改造为燃用甲醇燃料的甲醇发动机,并对甲醇发动机与原汽油发动机的瞬态排放特性进行了对比研究,分别检测了三效催化转化器后的常规污染物(CO、THC、NOx)和非常规污染物(甲醛、乙醛、甲醇、乙醇、氨)的排放。结果表明,甲醇发动机3种常规污染物的排放都明显低于汽油发动机,但非常规污染物甲醛和乙醛的排放高于汽油发动机;装用三效催化转化器使二者的氨排放都增高,前者增高的幅度更大。

关键词：甲醇发动机汽油发动机瞬态排放常规排放非常规排放

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嵌入式系统在铁路道口报警系统中的应用

微计算机信息 2006年第2Z期22卷 64-66页

作者：高俊华天津铁道职业技术学院网络教研室天津市河北区300240

本文介绍的嵌入式系统在铁路平交道口自动报警系统中应用,采用微软的WindowsCE操作系统,基于PC/104总线的PCM3350主机和PCM3724硬件平台,上位机采用组态软件MCGS所开发的嵌入版。

关键词：嵌入式系统 MCGS 道口报警自动控制

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金属基外延石墨烯相图非谐效应探讨

功能材料 2020年第5期51卷 5118-5123页

作者：高君华郑瑞伦重庆文理学院电子信息与电气工程学院重庆市高校新型储能器件及应用工程研究中心重庆402160

考虑到原子的非简谐振动,建立了物理模型,应用固体物理理论和方法,研究了金属基外延石墨烯电子系统的可能状态和相图,并以钨基底上的外延石墨烯为例,探讨了原子非谐振动和电子排斥作用对相图的影响。结果表明,(1)金属基外延石墨烯电子... 详细信息

考虑到原子的非简谐振动,建立了物理模型,应用固体物理理论和方法,研究了金属基外延石墨烯电子系统的可能状态和相图,并以钨基底上的外延石墨烯为例,探讨了原子非谐振动和电子排斥作用对相图的影响。结果表明,(1)金属基外延石墨烯电子系统有3种可能相:自旋波状态(BC)的反铁磁相、电荷密度态(BZ)的顺磁相和半金属态(PM)的半金属相;(2)外延石墨烯呈现的相,取决于石墨烯中原子内部电子关联U和原子间电子关联G的变化。对钨基外延石墨烯而言,当U=0.33284 eV和G=0.11904 eV时,会出现半金属相、反铁磁相、顺磁相三相共存;(3)原子的非简谐振动对金属基外延石墨烯的相图有重要的影响。不考虑原子非简谐振动时,外延石墨烯的相变曲线与温度无关;而考虑原子非简谐振动后,相变曲线不仅与温度有关,而且对发生相变的条件要求更高:原子内部电子关联U要更强。温度愈高,发生半金属-反铁磁-顺磁相变愈难,原子非简谐振动效应愈显著。

关键词：金属基外延石墨烯相图非谐效应电子-电子排斥作用

SCR系统国Ⅴ柴油机适用基准燃油的排放试验研究

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汽车工程 2014年第3期36卷 273-276,320页

作者：关敏王凤滨高俊华中国环境科学研究院北京100012 中国汽车技术研究中心天津300162

对一满足国Ⅴ阶段排放标准的共轨SCR后处理柴油机进行研究,分别使用符合国Ⅲ、国Ⅳ和国Ⅴ柴油要求的基准燃油,按照法规GB 17691—2005规定的试验内容进行测试。结果表明,燃油品质对发动机动力性和经济性影响较小;而随着燃油品质的下降,... 详细信息

对一满足国Ⅴ阶段排放标准的共轨SCR后处理柴油机进行研究,分别使用符合国Ⅲ、国Ⅳ和国Ⅴ柴油要求的基准燃油,按照法规GB 17691—2005规定的试验内容进行测试。结果表明,燃油品质对发动机动力性和经济性影响较小;而随着燃油品质的下降,ESC和ETC测试的微粒排放和ESC测试的NOx排放呈增长趋势;而NOx排放ETC测试的结果相反,呈减少趋势;除了国Ⅲ柴油的ESC试验无法达到法规国Ⅴ阶段要求限值外,其余各种燃油的测试均符合法规要求。

关键词：柴油机基准柴油排放