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应用型高校工科专业就业工作路径研究

模具制造 2024年第5期24卷 71-73页

作者：吕玲山西大同大学山西大同037000

应用型高校工科专业学生就业牵动着制造业的迭代升级,也关系着千家万户的幸福稳定。高校辅导员在认真落实党中央、教育部相关工作部署下,应当思考就业指导工作的有效性、可行性、精准性,在适应社会发展、满足企业需要的前提下,积极探索... 详细信息

应用型高校工科专业学生就业牵动着制造业的迭代升级,也关系着千家万户的幸福稳定。高校辅导员在认真落实党中央、教育部相关工作部署下,应当思考就业指导工作的有效性、可行性、精准性,在适应社会发展、满足企业需要的前提下,积极探索更加贴近学生实际、提升学生能力、矫正就业观念的就业指导工作路径。

关键词：就业指导工作工科学生路径研究

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ANAlYSIS OF STRESS CONCENTRATIONS IN UNIDIRECTIONAl COMPOSITES TAKING INTO ACCOUNT THE TENSIlE lOAD IN THE MATRIX

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Acta Mechanica Solida Sinica 1998年第4期11卷 318-328页

作者： ling, l Zeng, QD Guangdong Univ Technol Dept Mechatron Engn Guangzhou 510643 Peoples R China S China Univ Technol Dept Engn Mech Canton 510641 Peoples R China

A modified shear-lag model accounting for the effect of the tensile stiffness of the ma, trix is proposed for solving the stress redistribution due to the failure of fibers and matrix in unidirectionally fibre-reinforced composites. The advantages of this model are simple, reasonable and accurate by comparison with the other similar modified shear-lag models. It can be further extended to study the stress redistribution with interfacial damage between fibres and matrix This paper quantitatively dis cusses the influence of the tensile stiffness ratio of matrix to fibre and of the fibre volume fraction on the stress concentration in the fibres and ma trix adjacent to cut fibres and matrix, and suggests that the influence of the matrix stiffness on the stress concentration can be neglected when the matrix stiffness is low, such as polymer matrix composites, and the fibre volume fraction is high. For other cases such as ceramic and metal matrix composites, the tensile load of the matrix cannot be neglected in the shear-lag analysis.

关键词： unidirectional composites stress concentration matrix stiffness shear-lag analysis

Parameter identification and synchronization of spatiotemporal chaos in an uncertain Gray-Scott system

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Science China(Physics,Mechanics & Astronomy) 2008年第11期51卷 1638-1646页

作者： lüling lI Yi GUO ZhiAn College of Physics and Electronic Technology Liaoning Normal UniversityDalian 116029China Department of Mathematics and Physics Dalian Jiaotong UniversityDalian 116028China

The zero-asymptotic property of sliding variables in discrete systems is extended to a continuous one and applied to partial differential equations which describe spatiotemporal chaos. A method of chaos synchronization and parameter identifi-cation is proposed. The synchronization controllers and the parameter recognizers are designed. The uncertain Gray-Scott system is taken as an example to verify the effectiveness of the method. Simulation results show that the identification vari-ables in the parameter recognizers may take the place of the unknown parameters in both target and response systems. Global synchronization of the two spatio-temporal chaotic systems with uncertain parameters may be realized quickly after controllers are added.

关键词： spatiotemporal chaos sliding variable parameter identification synchronization uncertain Gray-Scott system

Theoretical Studies on the Intermonomer Interaction of F^(-)·(H_(2)O)_(n)(n=1,2)

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Chinese Journal of Structural Chemistry 2005年第5期24卷 561-567,491页

作者： WANG Yong-Cheng lüling-ling GENG Zhi-Yuan DAI Guo-liang WANG Dong-Mei Department of Chemistry Northwest Normal UniversityLanzhou 730070China Department of Chemistry Tianshui Normal UniversityGansu 741009China

Five optimized geometries of F-?(H2O)n (n = 1, 2) were obtained with ab initio calculation at the B3lYP/6-311++G** level. The accurate intermonomer interaction energy was calculated using the MP2 electron correlation correction as well as the basis set superposition error correction by the Boys-Bernardi “counterpoise” protocol. Natural bond orbital (NBO) theory was applied to quantify the relative strength of these interactions and account for their effects on the stability, structural and vibrational parameters of Fˉ?(H2O)n (n = 1, 2). It is shown that the charge transferring from the lone pair of F-1 to the σ?OH(…F) antibonding orbital is important. The results indicate the occupancy of σ?OH(…F) is increased (denoted ?σ?OH(…F)) and the σOH(…F) bond is leng- thened (denoted ?ROH(…F)), leading to the red-shift and the red-shift values have linear correlation with both ?σ?OH(…F) and ?ROH(…F).

关键词： F^(-)·(H_(2)O)_(n)(n=1,2) interaction energy red-shift linear correlation

基于锗硅异质结双极晶体管的低噪声放大器及其反模结构的单粒子瞬态数值仿真研究

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物理学报 2024年第12期73卷 288-299页

作者：黄馨雨张晋新王信吕玲郭红霞冯娟闫允一王辉戚钧翔西安电子科技大学空间科学与技术学院西安710049 中国科学院新疆理化技术研究所乌鲁木齐830011 西北核技术研究院西安710024

针对锗硅异质结双极晶体管(SiGe HBT)进行TCAD仿真建模,基于SiGe HBT器件模型搭建低噪放大器(lNA)电路,开展单粒子瞬态(SET)的混合仿真,研究SET脉冲随离子不同lET值、入射角度的变化规律.结果表明:随着入射离子lET值的增大,lNA端口的SE... 详细信息

针对锗硅异质结双极晶体管(SiGe HBT)进行TCAD仿真建模,基于SiGe HBT器件模型搭建低噪放大器(lNA)电路,开展单粒子瞬态(SET)的混合仿真,研究SET脉冲随离子不同lET值、入射角度的变化规律.结果表明:随着入射离子lET值的增大,lNA端口的SET脉冲的幅值增大,振荡时间延长;随着离子入射角的增大,lNA端口的SET脉冲的幅值先增大后减小,振荡时间减小.使用反模(IM)共射共基结构(Cascode)降低lNA对单粒子效应的敏感度,验证了采用IM结构的lNA电路的相关射频性能.针对离子于共基极(CB)晶体管、共发射极(CE)晶体管两种位置入射进行SET实验.实验结果与本实验中的正向模式相比,IM Cascode结构的lNA电路的瞬态电流持续时间明显减少,并且峰值减小了66%及以上.

关键词：锗硅异质结双极晶体管单粒子效应反模混合仿真

De-emulsification of 2-ethyl-1-hexanol/water emulsion using oil-wet narrow channel combined with low-speed rotation

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Chinese Journal of Chemical Engineering 2018年第10期26卷 2048-2054页

作者： ling lü Kejing Wu You Tang Siyang Tang Bin liang Multi-phases Mass Transfer and Reaction Engineering laboratory College of Chemical Engineering Sichuan University College of Chemical Engineering and Chemistry Technology Southwest Petroleum University

low-speed rotation of disc in an internal circulation of a novel de-emulsification with rotation-dise horizental contactor(RHC-D) realized de-emulsification for O/W emulsions due to repeated coalescence in oil-wet narrow channels at a low rotation speed. For three emulsions included ethanol/water/2-ethyl-1-hexanol, ethanol/water/2-ethyl-1-hexanol/SDS(Sodium Dodecyl Sulfonate) and 2-ethyl-1-hexanol/water/SDS emulsion, deemulsification ratios of oil phase could reach 1, 1 and 0.67 respectively at 170 r·min-1, and de-emulsification ratios increased obviously after agitating 10 min. De-emulsification experiment in the seam indicated that oil droplet sizes in O/W emulsion became larger after de-emulsification. The main de-emulsification mechanism in RHCD was the coalescence of oil droplets in oil-wet narrow channels. With increase of the rotation speed, oil droplets dispersed better in the aqueous phase. However, de-emulsification effect enhanced due to the increase of the coalescence rate at a bit higher rotation speed. In addition, internal circulation made those O/W emulsions to be broken repeatedly, consequently de-emulsification ratio increased. Repeated de-emulsification through internal circulation might make continuous extraction of ethanol come true at a low rotation speed.

关键词： De-emulsification Oil-wet channel low rotation speed O/W emulsion Internal circulation

重离子辐射对AlGaN/GaN高电子迁移率晶体管低频噪声特性的影响

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物理学报 2024年第3期73卷 209-216页

作者：吕玲邢木涵薛博瑞曹艳荣胡培培郑雪峰马晓华郝跃西安电子科技大学微电子学院西安710071 西安电子科技大学机电工程学院西安710071 中国科学院近代物理研究所兰州730000

采用^(181)Ta^(32+)重离子辐射AlGaN/GaN高电子迁移率晶体管,获得器件在重离子辐射前后的电学特性和低频噪声特性.重离子辐射导致器件的阈值电压正向漂移、最大饱和电流减小等电学参数的退化.微光显微测试发现辐射后器件热点数量明显增... 详细信息

采用^(181)Ta^(32+)重离子辐射AlGaN/GaN高电子迁移率晶体管,获得器件在重离子辐射前后的电学特性和低频噪声特性.重离子辐射导致器件的阈值电压正向漂移、最大饱和电流减小等电学参数的退化.微光显微测试发现辐射后器件热点数量明显增加,引入更多缺陷.随着辐射注量的增加,电流噪声功率谱密度逐渐增大,在注量为1×10^(10)ions/cm^(2)重离子辐射后,缺陷密度增大到3.19×10^(18)cm^(-3)·eV^(-1),不同栅压下的Hooge参数增大.通过漏极电流噪声归一化功率谱密度随偏置电压的变化分析,发现重离子辐射产生的缺陷会导致寄生串联电阻增大.

关键词：重离子辐射氮化镓高电子迁移率晶体管低频噪声

A note on the numerical simulations of flow past a wavy square-section cylinder

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Acta Mechanica Sinica 2008年第1期24卷 101-105页

作者： G. C. ling l. M. lin The State Key laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

The flow past a square-section cylinder with a geometric disturbance is investigated by numerical simulations. The extra terms, due to the introduction of mapping transformation simulating the effect of disturbance into the transformed Navier-Stokes equations, are correctly derived, and the incorrect ones in the previous literature are pointed out and analyzed. Furthermore, the relationship between the vorticity, especially on the cylinder surface, and the disturbance is derived and explained theoretically. The computations are performed at two Reynolds numbers of 100 and 180 and three amplitudes of waviness of 0.006, 0.025 and 0.167 with another aim to explore the effects of different Reynolds numbers and disturbance on the vortex dynamics in the wake and forces on the body. Numerical results have shown that, at the mild waviness of 0.025, the Kairmain vortex shedding is suppressed completely for Re = 100, while the forced vortex dislocation is appeared in the near wake at the Reynolds number of 180. The drag reduction is up to 21.6% at Re = 100 and 25.7% at Re = 180 for the high waviness of 0.167 compared with the non-wavy cylinder. The lift and the Strouhal number varied with different Reynolds numbers and the wave steepness are also obtained.

关键词： Numerical simulation. Geometric disturbance.Square-section cylinder Wake flow

广西喀斯特地区4种饲用甜高粱农艺性状、营养成分及相对饲喂价值分析

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饲料研究 2024年第10期47卷 130-133页

作者：易显菊张辉吕玲燕庞天德易显凤广西畜禽品种改良站广西南宁530002 广西浩众农业科技有限公司广西南宁530201 广西农业职业技术大学广西南宁530007

研究旨在筛选出适合广西喀斯特地区种植的饲用甜高粱品种。试验以4种饲用甜高粱为研究对象,分析甜高粱的农艺性状、生物学产量、营养价值和相对饲喂价值。结果表明:甜高粱601的株高和分蘖数显著高于甜高粱326、901以及大力士(P<0.05),... 详细信息

研究旨在筛选出适合广西喀斯特地区种植的饲用甜高粱品种。试验以4种饲用甜高粱为研究对象,分析甜高粱的农艺性状、生物学产量、营养价值和相对饲喂价值。结果表明:甜高粱601的株高和分蘖数显著高于甜高粱326、901以及大力士(P<0.05),而大力士的茎粗和茎节数显著高于甜高粱326、601、901 (P<0.05),大力士和甜高粱901茎叶比显著高于甜高粱326和601 (P<0.05)。甜高粱326和601的鲜草产量、干草产量显著高于甜高粱901和大力士(P<0.05),甜高粱601干鲜比为31.34%,在所有品种中最高。大力士的粗蛋白含量高于甜高粱326、601和901;甜高粱901的粗纤维、酸性洗涤纤维含量显著高于大力士、甜高粱326和601 (P<0.05);甜高粱601的中性洗涤纤维含量为60.82%,显著高于大力士、甜高粱326和901 (P<0.05),甜高粱601粗脂肪和干物质含量分别为23.78 g/kg和31.17%,显著高于甜高粱326、901及大力士(P<0.05);甜高粱326的粗灰分含量为9.59%,在所有品种中最高。甜高粱326的干物质采食量、可消化干物质、相对饲用价值和可消化营养物质在所有品种中最高。研究表明,甜高粱326、601更适合在广西喀斯特地区种植。

关键词：广西喀斯特地区甜高粱农艺性状营养成分相对饲喂价值