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Journal of Iron and Steel Research International 2021年第6期28卷 669-678页

作者： Yan-yan Zhang ke-qin feng Yue Shui Si-tan Chen Yan-fang Liu School of Mechanical Engineering Sichuan UniversityChengdu 610065SichuanChina

In situ selective carbothermic reactions and vacuum sintering were used to prepare iron-based friction material directly vanadium-bearing titanomagnetite *** of phosphorus addition(0.05–0.20 wt.%)on the microstructure and properties of iron-based friction material were *** results show that the addition of phosphorus improves the microstructure and properties of the material *** phosphorus addition increases to 0.15 wt.%,the sintering densification is promoted and the number of lamellar pearlites ***,the relative density,hardness and tribological properties of the material are greatly ***,the friction coefficient decreases 0.58 to 0.43,and the wear rate reduces 1.829×10^(–7) to 0.694×10^(–7)cm^(3)J^(-1).The dominant wear mechanism of the material changes severe abrasive wear to mild oxidation wear ***,when phosphorus addition exceeds 0.15 wt.%,the matrix continuity and tribological properties of the material are ***,the optimal addition of phosphorus in the iron-based friction material is 0.15 wt.%.

关键词： Vanadium-bearing titanomagnetite concentrate Iron-based friction material Tribological behavior Phosphorus

A decomposition method of vortex identification and its application in side channel pumps

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Journal of Hydrodynamics 2022年第6期34卷 1106-1120页

作者： ke Chen Fan Zhang Yu-jian fang Desmond Appiah Shou-qi Yuan feng Hong National Research Center of Pumps Jiangsu UniversityZhenjiang212013China Quality Inspection Center for Pump Products in Zhejiang Province Wenling317599China College of Mechanical and Power Engineering China Three Gorges UniversityYi Chang443000China

This research utilizes theΩvortex identification method to address the turbulent flows in a single-stage side channel pump,to comprehensively characterize the three types of dynamic vortex structures classified based on *** on the Galilean invariance,the work employs coordinate rotation and ***,the indistinguishable 3-D vortex can be simplified to 2-D vortex on typical research *** juxtaposing the overall performance,it was revealed that a diversity of areas with high values yielded enhanced reflection of the vortex intensity,as measured by velocity *** axial vortex structure with high intensity exists at the outer radius under all conditions *** the longitudinal vortex usually shows high intensity between the middle and outer ***,the radial vortex is more likely to be at the inner radius near the suction ***,this paper introduces a specific valueξ,which represents the ratio of decomposition to the total of the manifestation of the fluid rotational *** the fluctuation and mean value,it can be realized that the development of the specific vortex in three directions at different *** example,the specific valueξ2 refers to the typical longitudinal vortex as dynamic vortex are almost from 20%to 50%,which illustrates that the longitudinal vortex only occupies a minor percentage in the total *** phenomenon is one of the main reasons for the low *** present work could provide some suggestions and references for in-depth studies in fluid engineering with intense swirling flows.

关键词： Side channel pumps unsteady flow Ω-criterion vortex evolution

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1,6-己二醇制备的研究

应用化工 2011年第7期40卷 1222-1225页

作者：荆宏健王俊伟杨丰科梁吉虎山西天脊煤化工集团有限公司山西潞城047507 青岛科技大学化工学院山东青岛266042

以己二酸为原料,以732型阳离子交换树脂为催化剂,在85℃下与甲醇反应5.5 h,生成己二酸二甲酯,产率>98%;在反应器中装入20～40目粒度催化剂Cu/ZnO/Al2O3,己二酸二甲酯与氢气反应,控制温度在250℃,氢气操作压力2.5 MPa,氢酯摩尔比150∶1,... 详细信息

以己二酸为原料,以732型阳离子交换树脂为催化剂,在85℃下与甲醇反应5.5 h,生成己二酸二甲酯,产率>98%;在反应器中装入20～40目粒度催化剂Cu/ZnO/Al2O3,己二酸二甲酯与氢气反应,控制温度在250℃,氢气操作压力2.5 MPa,氢酯摩尔比150∶1,己二酸二甲酯体积空速0.50 h-1。在此条件下反应,1,6-己二醇产率>96%。

关键词：己二酸己二酸二甲酯 1,6-己二醇催化氢化

On Factorization of Coupled Channel Scattering S Matrices

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Communications in Theoretical Physics 2007年第5X期48卷 901-907页

作者： fang ke-Jie Department of Physics Peking University Bei jing 100871 China

We investigate the problem on how to factorize a coupled channel scattering S matrix into a product of simple S matrices. Simple S matrix solntions are found, respecting unitarity, analyticity and being real analytic.... 详细信息

关键词： ππ scattering S matrix

Inhibitory gamma-aminobutyric acidergic neurons in the anterior cingulate cortex participate in the comorbidity of pain and emotion

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Neural Regeneration Research 2025年第10期20卷 2838-2854页

作者： Lu Guan Mengting Qiu Na Li Zhengxiang Zhou Ru Ye Liyan Zhong Yashuang Xu Junhui Ren Yi Liang Xiaomei Shao Jianqiao fang Junfan fang Junying Du Department of Neurobiology and Acupuncture Research Third School of Clinical MedicineZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina key Laboratory for Research of Acupuncture Treatment and Transformation of Emotional Diseases Third School of Clinical MedicineZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina Fuchun Community Health Service Center of Fuyang District HangzhouZhejiang ProvinceChina

Pain is often comorbid with emotional disorders such as anxiety and *** of the anterior cingulate cortex has been implicated in pain and pain-related negative emotions that arise from impairments in inhibitory gamma-aminobutyric acid *** review primarily aims to outline the main circuitry(including the input and output connectivity)of the anterior cingulate cortex and classification and functions of different gamma-aminobutyric acidergic neurons;it also describes the neurotransmitters/neuromodulators affecting these neurons,their intercommunication with other neurons,and their importance in mental comorbidities associated with chronic pain *** understanding on their role in pain-related mental comorbidities may facilitate the development of more effective treatments for these ***,the mechanisms that regulate gamma-aminobutyric acidergic systems remain *** is also unclear as to whether the mechanisms are presynaptic or *** exploration of the complexities of this system may reveal new pathways for research and drug development.

关键词： anterior cingulate cortex anxiety chronic pain circuit communication comorbidity depression gamma-aminobutyric acidergic neurons parvalbumin neurons synaptic transmission

The Representations of Generalized Inverses of Lower Triangular Operators

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Acta Mathematica Sinica,English Series 2009年第12期25卷 2107-2118页

作者： Chun fang SHAO Hong ke DU Shu feng JI Jun Lian XU College of Mathematics and Information Science Shaanxi Normal University Xi'an 710062 P. R. China Department of Mathematics Ankang University Ankang 725000 P. R. China

In this note, the explicit representations of Moore-Penrose inverses of lower triangular operator matrices are established. As an application, the explicit representations of Bott-Duffin inverses of bounded linear ope... 详细信息

关键词： Moore-Penrose inverse lower triangular operator matrix Bott-Duffin inverse

Rh(Ⅱ) carbene S-H insertion into H_2S via the stepwise mechanism

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Chinese Chemical Letters 2007年第1期18卷 107-110页

作者： Zhen feng Liu Xian fang Yue Qiang Wei ke Li Han State key Laboratory of Molecular Reaction Dynamics~ Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China

The mechanism of Rh（Ⅱ） carbene S-H insertion into H2S in gas phase has been studied by B3LYP functional. Calculation results showed that the Rh（Ⅱ） carbene S-H insertion into H2S took only stepwise channels and n... 详细信息

关键词： Sulfonium ylides 1,2-Hydrogen shift Density functional calculations Dirhodium(Ⅱ) carbene

Insertion of O—H Bond of Rh(Ⅱ)-methylene Carbene into Alcohols: A Stepwise Mechanism More Plausible than a Concerted Mechanism

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Chemical Research in Chinese Universities 2007年第2期23卷 221-225页

作者： LIU Zhen-feng WANG Yong YUE Xian-fang HAN ke-li State key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Sciences Dcdian 116023 P. R. China

The mechanisms of insertion of O-H bond of Rh（ Ⅱ ）-methylene carbene into methanol and ethanol were studied by using B3LYP functional both in gas phase and in CH2 C12. The formation of free alcoholic oxonium ylides is found to be impossible. Alcoholic oxonium ylide are formed as the intermediates before beth the stepwise and the concerted transition states of insertion of O-H bend of Rh（ Ⅱ ）-methylene carbene into methanol and ethanol. With re- gard to the mechanisms of insertion of O-H of Rh（ Ⅱ ） -methylene carbene into alcohols, analysis of the energy bartiers of the two mechanisms indicate that the stepwise mechanism is more plausible than the concerted mechanism.

关键词： Oxonium ylide 1,2-Hydrogen shift Density functional calculation Dirhodium( Ⅱ ) methylene carbene

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栗属植物叶片形态特征在种间识别的研究

电子显微学报 2021年第4期40卷 432-440页

作者：顾建成聂兴华曹小艳张煜张伟伟杜兵帅郑瑞杰房克凤秦岭邢宇北京农学院植物科学技术学院北京102206 北京农学院林木分子设计育种高精尖创新中心北京102206 辽宁省经济林研究所辽宁大连116000

本研究以栗属植物6个种的成熟叶片为材料,对其叶形特征进行调查、统计和分析,并通过体式显微镜、扫描电镜和塑料包埋切片对其叶背表皮组织进行综合显微观察分析。结果表明:(1)叶片形态特征,尤其叶形和叶形指数在栗属植物种间存在显著差... 详细信息

本研究以栗属植物6个种的成熟叶片为材料,对其叶形特征进行调查、统计和分析,并通过体式显微镜、扫描电镜和塑料包埋切片对其叶背表皮组织进行综合显微观察分析。结果表明:(1)叶片形态特征,尤其叶形和叶形指数在栗属植物种间存在显著差异,可以作为不同栗属植物初步识别的重要依据之一;(2)盾状腺毛的有无在栗属植物资源描述与评价中是一个不可代替的重要指标,是识别不同栗属植物的关键组织;(3)栗属植物的腺毛组织由多细胞构成,预测其具有分泌次生代谢物的功能,在自身病虫害防治、环境适应和抗逆性等方面可能发挥着重要作用。

关键词：栗属种间识别叶形指数叶表皮腺毛

An adaptive sequential experiment design method for model validation

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Chinese Journal of Aeronautics 2020年第6期33卷 1661-1672页

作者： ke fang Yuchen ZHOU Ping MA Control and Simulation Center Harbin Institute of TechnologyHarbin 150080China

Efficient experiment design is of great significance for the validation of simulation model with high nonlinearity and large input *** validation experiment raises the cost while insufficient test increases the risks of accepting an invalid *** this paper,an adaptive sequential experiment design method combining global exploration criterion and local exploitation criterion is *** exploration criterion utilizes discrepancy metric to improve the space-filling property of the design points while the exploitation criterion employs the leave one out error to discover informative *** avoid the clustering of samples in the local region,an adaptive weight updating approach is provided to maintain the balance between exploration and ***,the credibility distribution function characterizing the relationship between the input and result credibility is introduced to support the model validation experiment ***,six benchmark problems and an engineering case are applied to examine the performance of the proposed *** experiments indicate that the proposed method achieves satisfactory performance for function approximation in accuracy and convergence.

关键词： Adaptive sequential experiment design Credibility distribution function Gaussian process model Metamodeling Model validation