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结构光照明显微镜照明系统的设计与仿真

工具技术 2019年第7期53卷 99-102页

作者：柴常春闫红洲罗健张箎黄连刘晓军华中科技大学数字制造装备与技术国家重点实验室

结构光照明显微镜是一种结合结构照明技术与宽场成像原理实现表面形貌测量的新工具。为方便调节物面光强和照明视场大小,并保证结构光条纹的均匀性,基于科勒照明原理提出利用成品透镜与无限远物镜,并结合数字微镜阵列(DMD)设计结构光照... 详细信息

结构光照明显微镜是一种结合结构照明技术与宽场成像原理实现表面形貌测量的新工具。为方便调节物面光强和照明视场大小,并保证结构光条纹的均匀性,基于科勒照明原理提出利用成品透镜与无限远物镜,并结合数字微镜阵列(DMD)设计结构光照明显微镜照明系统的方法。通过Zemax软件建立设计模型进行仿真分析,验证了该方法设计的结构光照明系统投射到物面光照的均匀性。

关键词：结构光照明显微镜科勒照明 Zemax

A Study of Mechanical Properties of the Iron-base Sintered Steel Adding Fine Cr-Fe Powder

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稀有金属材料与工程 2011年第S3期40卷 5-8页

作者： Chen Hua 1 , Liu Yongbing 2 , Li Yueying 2 , Cao Zhanyi 2 , chai Zhilong 3 1 Key Laboratory of Advanced Structural Materials, Ministry of Education, changchun University of Technology, changchun 130012, China 2 Key Laboratory of Automobile Materials, Ministry of Education, Jilin University, changchun 130022,China 3 Research Institute of First Automobile Factory of China, changchun 130011, China changchun Univ Technol Sch Mat Sci & Engn Key Lab Adv Struct Mat Minist Educ Changchun 130012 Peoples R China Jilin Univ Key Lab Automobile Mat Minist Educ Changchun 130022 Peoples R China Res Inst First Automobile Factory China Changchun 130011 Peoples R China

This paper reports an investigation of the mechanical properties and the fracture mechanism of iron-based sintered alloy containing fine Cr-Fe powder particles 300 nm in size and in contents raging from 0.2-1.5 wt%. The iron-base alloy were sintered at 1120 ℃ for 40min. The results of the study revealed improvement in mechanical properties such as tensile strength, elongation and hardness of the sintered alloy. The fracture behaviors of the alloy were influenced significantly by the presence of Cr-Fe powder particles. The mechanical properties increased with increasing Cr content. Micrographs of fracture appeared dimple and quasi-cleavage.

关键词： sintered steel fine Cr-Fe powder mechanical properties

Crystal Structure of [Et_4N][Sm(S_2CNEt_2)_4]

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Chemical Research in Chinese Universities 1993年第2期9卷 139-142页

作者： SUN Chun-ting, WANG chai-xia, HUANG Qi-jun, LANG Xi-guang,ZHU Ya-bin LU Gong-xian (Department of Chemistry, Jilin University, changchun, 130023)WEI Ge-cheng, JIN Zhong-sheng and LIU Yong-sheng (changchun Institute of Applied Chemistry, Academy of Sciences, changchun, 130022)

The crystal structure of .[Et4N][Sm(S2CNEt2)4] was determined by X-ray diffraction technique. The crystal crystallizes in monoclinic system, space group P21/n with a= 1. 1695(3), b=2.0821(6), c=1.7420(7) nm, β=99. 79(3)°? Z=4, Dc= 1. 39 g/ cm3, μ(Mo/KTσ) = 18. 4 cm-1, F(000) = 1812. The structure was solved by Patterson and Fourier techniques and refined by least-squares method to a final conventional R of 0. 053 for 3116 (Ⅰ> 3σ- (Ⅰ)) reflections. Each asymmetric unit contains two ions [Sm (S2CNEt2)4]-1 and [Et4N] +1, having distance between central atoms N5 and Sm3+ to be 0. 6522 nm. The atom Sm is coordinated by eight sulphur atoms. The Sm-S distance lies in the range of 0. 285-0. 290 nm with an average of 0. 288 nm.

关键词： Crystal Structure X-ray diffraction

The Photovoltage-gas Sensitive Properties of 7,7,8,8-Tetracyanoquinodimethane(TCNQ)

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Chemical Research in Chinese Universities 1990年第4期6卷 341-345页

作者： Jiang Lei, Wang Dejun, Liu Wang, chai Xiangdong and Li Tiejin (Department of Chemistry, Jilin University, changchun)

In this paper, surface photovoltage technique (SPV) was applied to the study of photovoltaic and gas sensitive properties of TCNQ polycrystal. It was found that SPV shows two peaks at 390 nm(P1) and 480 nm (P2) in the ultraviolet-visible range. And they are opposite in phase. The results of gaseous adsorption confirm that P, shows the acceptor characteristics, while PI shows that of donor. During adsorption, donor gas interacts with conjugated II * orbital, acceptor gas with the terminal group C=N .

关键词： Surface photovoltage Gas sensitivity Adsorption

Highly sensitive hybrid nanofiber-based room-temperature CO sensors： Experiments and density functional theory simulations

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Nano Research 2018年第2期11卷 1029-1037页

作者： Lili Wang Ruiqing chai Zheng Lou Guozhen Shen State Key Laboratory on Integrated Optoelectronics College of Electronic Science and Engineering Jilin University Changchun China State Key Laboratory for Superlattices and Microstructures Institute of Semiconductors Chinese Academy of Sciences Beijing China College of Materials Science and Opto-electronic Technology University of Chinese Academy of Sciences Beijing China

Chemical sensors （CSs） are an emerging area in nanoscience research, which focuses on the highly sensitive detection of toxic and hazardous gases and disease- related volatile organics. While the field has advanced rapidly in recent years, it lacks the theoretical support required for the rational design of innovative materials with tunable measurement responses. Herein, we present a one-dimensional （1D） hybrid nanofiber decorated with ultrafine NiO nanoparticles （NiO NPs） as an efficient active component for CSs. Highly dispersed （110）-facet NiO NPs with a high percentage of Ni2~ active sites with unsaturated coordination were confined in a TiO2 nanofiber （TiO2 NF） matrix that is favorable for surface catalytic reactions. The CSs constructed using the 1D heterostructure NiO/TiO2 nanofibers （NiOdrio2 HNFs） exhibited a highly selective response to trace CO gas molecules （1 ppm） with high sensitivity （AR/Ro = 1.02）, ultrafast response/ recovery time （T 〈 20 s）, and remarkable reproducibility at room tem- perature. The density functional theory （DFT） simulations and experimental results confirmed that the selective response could be attributed to the high molecular adsorption energy of the NiO nanoparticles with （110） facets and abundant interfaces, which act synergistically to promote CO adsorption and facilitate charge transfer.

关键词： hybrid nanofiber high active facet gas sensor selectivity highly sensitive density functional theory

X-Ray Photoelectron Spectroscopic Study on the Synthesis of Copper Sulphide in LB Films( Ⅱ )

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Chemical Research in Chinese Universities 1992年第4期8卷 395-398页

作者： CHEN Hui-juan, chai Xiang-dong, WEI Quan , JIANG Yue-shun and LI Tie-jin (Department of Chemistry, Jilin University, changchun, 130023)

The present paper covers the formation process of copper sulphide in copper stearate Langmuir-Blodgett films studied carefully by XPS. The further identification of sulfur species and the examination of its change in the reaction have been made. Also the formation mechanism of sulfur species in the special microenvironment-LB films is discussed.

关键词： XPS LB film Copper sulphide

Terminal sliding mode control of rail pressure for gasoline direct injection engines

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Control Theory and Technology 2019年第2期17卷 183-189页

作者： Chen ZHANG Ying ZHANG Cong chai Miaolei ZHOU Department of Control Science and Engineering Jilin UniversityChangchun Jilin 130022China

The desired fuel rail pressure is a crucial factor for guaranteeing the gasoli ne direct injecti on(GDI)en gine to work *** order to solve the rail pressure control problem,the detailed no nlinear model of GDI is derived and reas on able simplification of this model is carried out for the following controller *** sliding mode control strategy is proposed to design the rail pressure controller with Lyapunov *** designed approach with the fast terminal sliding mode surface makes the system have the capacity of global fast con vergence and achieves precise tracking *** demonstrate the validity of the desig ned control method,simulations are conducted by tracking the different reference rail *** show that the designed controller tracks the given reference accurately and has strong robustness.

关键词： Rail pressure control terminal sliding mode control GDI system

Self-assisted stereospecific polymerization of unmasked polar 4-methylthio-1-butene

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Science China Chemistry 2019年第6期62卷 761-766页

作者： Yunjie chai Chunji Wu Dongtao Liu Mingtao Run Dongmei Cui College of Chemistry and Environmental Science Hebei University State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences

Stereospecific polymerization of polar olefins has always been an attractive but challenging project because the Lewis basic polar groups of monomers are usually poisonous to the Lewis acidic metal centers of the catalysts. In this contribution,thiophene-fused cyclopentadienyl scandium complexes 1-3 were successfully synthesized. Combined with alkylaluminium and organoborate, these complexes showed extremely low activity and no selectivity for 1-hexene polymerization. Surprisingly,highly stereo-selective coordination polymerization of unprotected polar 4-methylthio-1-butene has been achieved in high activity for the first time under the same polymerization conditions. High-molecular-weight(M_n=110×10~3) and perfectly syndiotactic(rrrr>99%) poly(4-methylthio-1-butene)(P(MTB)) was afforded. Thus the methylthio-group-assisted mechanism that the unmasked methylthio group promoted the polymerization through σ-π chelation to the active scandium center together with the vinyl group was proposed. Moreover, the methylsulfonyl functionalized syndiotactic poly(1-butene) was also easily prepared by the oxidation of P(MTB). These results provided a new route for the synthesis of functionalized stereo-regular polyolefins.

关键词： self-assisted polymerization stereoselectivity polar α-olefin rare-earth metal catalyst functionalized poly(1-butene)

中国城市流动人口住房质量的空间分异与影响因素

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地理学报 2021年第12期76卷 2944-2963页

作者：王宇凡柴康妮卓云霞冯长春北京大学城市与环境学院北京100871

基于2015年全国1%人口抽样调查和2014年流动人口动态监测调查(CMDS)数据,本文以房屋面积、设施条件、建筑年代和社区类型来衡量流动人口住房质量,运用空间统计工具探讨了中国310个地级及以上行政单元流动人口住房质量的空间分异特征,进... 详细信息

基于2015年全国1%人口抽样调查和2014年流动人口动态监测调查(CMDS)数据,本文以房屋面积、设施条件、建筑年代和社区类型来衡量流动人口住房质量,运用空间统计工具探讨了中国310个地级及以上行政单元流动人口住房质量的空间分异特征,进而通过空间计量模型考察流动人口住房质量的影响因素。研究发现:(1)流动人口住房整体水平虽不及本地居民,但差距并不悬殊;(2)流动人口住房质量的空间差异明显,中部地区流动人口住房质量最高,东部、西部和东北地区在住房质量4个方面各有劣势;(3)按照行政等级和规模等级划分,中等城市流动人口住房质量最好,超大城市住房质量最差;(4)流动人口住房质量呈现出显著的空间正相关,但各指标高、低值集聚区的分布格局存在一定差异;(5)流动人口个体(内部特征)和流入地(外部特征)因素对流动人口住房质量具有显著影响,分别作用于不同的方面;(6)中小城市和大城市流动人口住房质量的决定因素及作用强度不尽相同。

关键词：中国城市流动人口住房质量空间分异影响因素