检索结果-南通市图书馆

Acta Metallurgica Sinica(English Letters) 2015年第4期28卷 477-486页

作者： zheng-Bing Wang Hong-Xiang Hu Chun-Bo liu Huai-ning Chen Yu-Gui zheng Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of Sciences Center for Wear and Corrosion Resistant Materials Huadian Zhengzhou Mechanical Design Institute Co.Ltd. Laboratory of Properties and Reliable Joining of Welded Joints Institute of Metal ResearchChinese Academy of Sciences

The corrosion behaviors of pure titanium and its weldment welded by tungsten inert gas （TIG） welding in simulated desulfurized flue gas condensates in thermal power plant chimney were investigated using potentiodynamic polarization, electrochemical impedance spectroscopy （EIS） and immersion tests. The effects of heat input and shielding gases on the corrosion behavior of the welded titanium were also studied. Grain coarsening and Widmanst^itten structure were found in both the fusion zone and the heat-affected zone. The welded titanium exhibited active-passive behavior in the simulated condensates. Both the polarization curves and EIS measurements confirmed that TIG welding process with different parameters had few effects on the corrosion behavior. It was proved that the microstructure changes were not the key material factors affecting the corrosion behavior of pure titanium under the test conditions, while the oxide film had remarkable effect on improving the corrosion resistance.

关键词： Pure titanium Tungsten inert gas welding Simulated desulfurized flue gas condensates Corrosion behavior Microstructure Oxide film

Chaihu-Shugan-San exerts an antidepressive effect by downregulating miR-124 and releasing inhibition of the MAPK14 and Gria3 signaling pathways

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2018年第5期13卷 837-845页

作者： Qiong liu ning-ning Sun zheng-Zhi Wu Da-Hua Fan Mei-Qun Cao Department of Cardiovascular Medicine Xiang Ya Hospital of Central South University Changsha Hunan Province China Shenzhen Institute of Geriatrics Shenzhen Second People's Hospital The First Affiliated Hospital of Shenzhen University Shenzhen Guangdong Province China The Eighth Affiliated Hospital of Sun Yat-sen University Shenzhen Guangdong Province China Chinese and Wsetern Integrative Medicine Shcool of Medicine Jinan University Guangzhou Guangdong Province China.

Dysregulation of mi R-124 has been reported to be involved in the pathophysiology of depression. Chaihu-Shugan-San, a traditional Chinese medicine, has antidepressive activity; however, the underlying mechanisms remain unclear. In this study, to generate a rodent model of depression, rats were subjected to a combination of solitary confinement and chronic unpredictable mild stress for 28 days. Rats were intragastrically administered Chaihu-Shugan-San（2.835 m L/kg/d） for 4 weeks, once a day. Real-time reverse-transcription quantitative polymerase chain reaction, mi RNA microarray, western blot assay and transmission electron microscopy demonstrated that ChaihuShugan-San downregulated mi R-124 expression and upregulated the m RNA and protein levels of mitogen-activated protein kinase 14（MAPK14） and glutamate receptor subunit 3（Gria3）. Chaihu-Shugan-San also promoted synapse formation in the hippocampus. The open field test, sucrose consumption test and forced swimming test were used to assess depression-like behavior. After intragastric administration of Chaihu-Shugan-San, sucrose consumption increased, while the depressive behaviors were substantially reduced. Together, these findings suggest that Chaihu-Shugan-San exerts an antidepressant-like effect by downregulating mi R-124 expression and by releasing the inhibition of the MAPK14 and Gria3 signaling pathways.

关键词： nerve regeneration traditional Chinese medicine Chaihu-Shugan-San depression open-field test sucrose consumption test forced swimming test miR-124 neural plasticity MAPK14 Gria3 neural regeneration

基于光电对射阵列下谷物收获流量控制系统的设计

在线全文

学校读者我要写书评

暂无评论

农机化研究 2025年第1期47卷 142-147页

作者：刘成林郑世界四川城市职业学院成都610110 成都工业职业技术学院成都610213

在谷物收获过程中,由于谷物的性质不同及收获机械的工作状态不同,谷物的流量往往会出现波动或过大过小的情况,直接影响谷物的收获效率和质量,甚至会导致收获机械的故障。因此,对谷物的流量进行准确的控制和调节是非常重要的。为此,设计... 详细信息

在谷物收获过程中,由于谷物的性质不同及收获机械的工作状态不同,谷物的流量往往会出现波动或过大过小的情况,直接影响谷物的收获效率和质量,甚至会导致收获机械的故障。因此,对谷物的流量进行准确的控制和调节是非常重要的。为此,设计了一种基于光电对射阵列的谷物收获流量控制系统,可通过使用光电对射阵列检测收获机的运动状态和收获物料的流量,进而控制收获机的速度和工作状态,以实现谷物的准确收获和控制流量。试验验证表明:系统具有较高的准确性和稳定性,能够有效地控制谷物的流量,提高收获效率和质量,具有广泛的应用前景。

关键词：谷物收获流量控制光电对射阵列传感器监测

维普期刊数据库博看期刊

Inducing human induced pluripotent stem cell differentiation through embryoid bodies:A practical and stable approach

在线全文

学校读者我要写书评

暂无评论

World Journal of Stem Cells 2020年第1期12卷 25-34页

作者： ning-ning Guo Li-Ping liu Yun-Wen zheng Yu-Mei Li Institute of Regenerative Medicine Affiliated Hospital of Jiangsu UniversityJiangsu UniversityZhenjiang 212001Jiangsu ProvinceChina Department of Gastrointestinal and Hepato-Biliary-Pancreatic Surgery University of Tsukuba Faculty of MedicineTsukubaIbaraki 305-8575Japan Yokohama City University School of Medicine YokohamaKanagawa 234-0006Japan Division of Regenerative Medicine Center for Stem Cell Biology and Regenerative MedicineThe Institute of Medical Sciencethe University of TokyoTokyo 108-8639Japan

Human induced pluripotent stem cells(hiPSCs)are invaluable resources for producing high-quality differentiated cells in unlimited quantities for both basic research and clinical *** are particularly useful for studying human disease mechanisms in vitro by making it possible to circumvent the ethical issues of human embryonic stem cell ***,significant limitations exist when using conventional flat culturing methods especially concerning cell expansion,differentiation efficiency,stability maintenance and multicellular 3D structure establishment,differentiation *** bodies(EBs),the multicellular aggregates spontaneously generated from iPSCs in the suspension system,might help to address these *** to the unique microenvironment and cell communication in EB structure that a 2D culture system cannot achieve,EBs have been widely applied in hiPSC-derived differentiation and show significant advantages especially in scaling up culturing,differentiation efficiency enhancement,ex vivo simulation,and organoid *** can potentially also be used in early prediction of iPSC differentiation *** improve the stability and feasibility of EB-mediated differentiation and generate high quality EBs,critical factors including iPSC pluripotency maintenance,generation of uniform morphology using micro-pattern 3D culture systems,proper cellular density inoculation,and EB size control are discussed on the basis of both published data and our own laboratory ***,the production of a large quantity of homogeneous EBs with high quality is important for the stability and feasibility of many PSCs related studies.

关键词： Induced pluripotent stem cells Suspension culture Embryoid body Early prediction Committed differentiation Heterogeneity Three-dimensional culture Scaling-up Quality control

CuInS_(2)/TiO_(2) heterojunction with elevated photo-electrochemical performance for cathodic protection

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2022年第27期122卷 211-218页

作者： Juan liu ning Wang Fuwei zheng Chuanxing Wang Jing Wang Baorong Hou Qianyu Zhao Yanli ning Yiteng Hu College of Chemical Engineering Qingdao University of Science and TechnologyQingdao 266042China CAS Key Laboratory of Marine Environmental Corrosion and Bio-Fouling Institute of OceanologyChinese Academy of SciencesNo.7 Nanhai RoadQingdao 266071China Pilot National Laboratory for Marine Science and Technology Open Studio for Marine Corrosion and ProtectionQingdao 266237China Center for Ocean Mega-Science Chinese Academy of SciencesNo.7 Nanhai RoadQingdao 266071China

Semiconductor quantum dots with high quantum yield and photovoltaic conversion efficiency have ushered in a brilliant moment for constructing internal electric field heterojunctions for photogenerated cathodic protection *** this paper,TiO_(2)nanotubes grown vertically on the surface of titanium substrates were modified via a combination of conventional electrochemical oxidation and a one-step solvothermal pathway to sensitize with CuInS_(2)quantum *** with pure TiO_(2)photoelectrodes,the modification improves sunlight absorption efficiency and provides photoelectron cathodic protection to the 304 stainless steel(304 SS).Through 9 h solvothermal reaction,the CuInS_(2)/TiO_(2)coupled with protected 304 SS exhibited an excellent property when the simulated sunlight *** mixed open circuit potential is negatively shifted to-0.99 V,at the mean time with a stable photocurrent density(118μA cm^(-2)).The results indicate that CuInS_(2)and TiO_(2)established a p-n heterojunction with wellmatched energy level,which can effectively facilitate the carrier separation and retain the strong redox capbility of photo-induced electrons and holes.

关键词： CuInS_(2)/TiO_(2)photoanode p-n heterojunction Cathodic protection Photoelectric conversion efficiency

Hot deformation behavior and microstructure evolution of an Fe–30Cr–2Mo ultra-pure super ferritic stainless steel

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2021年第10期28卷 1291-1304页

作者： Yang-yang Zhu Li-kui ning Tong-zheng Xin En-ze liu Jian Tong zheng Tan Yang-tao Zhou Zhi zheng Institute of Metal Research Chinese Academy of SciencesShenyang110016LiaoningChina School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016LiaoningChina School of Materials Science and Engineering University of New South WalesSydneyNSW2052Australia

The hot deformation behavior and microstructure evolution of an Fe–30Cr–2Mo ultra-pure super ferritic stainless steel were investigated at the temperature range of 950–1150℃ and strain rate varying from 0.01 to 10 s^(−1).A strain compensated constitutive equation based on the Arrhenius-type model was established to predict the flow *** hot processing map based on the dynamic materials model was achieved to identify the optimum processing *** addition,the features of microstructure evolution combined with the processing map were systematically *** experimental results revealed that the flow stress increased with decreasing deformation temperature or increasing strain *** recovery was confirmed to be the predominant softening *** values of flow stress predicted by the strain compensated constitutive equation agreed well with the experimental *** extent of dynamic recrystallization and recrystallized grain size increased with increasing deformation temperature or decreasing strain rate,and the continuous dynamic recrystallization was attributed to be the predominant mechanism of recrystallization during hot *** optimum hot working parameters were determined to be the deformation temperature of 1070–1150℃ and strain rate of 0.1–1 s^(−1) with a peak power dissipation efficiency of 42%.

关键词： Super ferritic stainless steel Hot compression Constitutive equation Processing map Microstructure evolution

Study of thermal decoherence of harmonic oscillators

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

原子与分子物理学报 2025年第5期42卷 108-114页

作者： LI Jian ZHOU Gao-Liang YAN zheng-Xin liu Wei WANG Zhao-Qi College of Science Xi’an University of Science and TechnologyXi’an 710054China

The thermal decoherence of harmonic oscillators is investigated *** quantum system presented here is a one-dimensional oscillator with angular frequency,which is surrounded by a thermal bath of environmental *** are various environmental oscillators with different angular frequency(below an ultraviolet cutoff).At the beginning,the quantum system is a pure state and the environmental oscillators are in thermodynamic equilibrium with *** a period,the system-environment interactions inspire significant decoherence of the quantum *** decoherence is displayed by explicit calculations of the purity and von Neumann entropy of the quantum *** is worth noting that the decoherence could be significant even in the weak coupling and low temperature case due to the large amount of environmental degrees of *** the decoherence process is inspired between the quantum system and an ordinary thermal environment here,the thermal decoherence result is quite general.

关键词： Quantum decoherence Grand canonical ensemble Oscillators

The application of back-scattered electron imaging for characterization of pearlitic steels

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2011年第9期54卷 2368-2372页

作者： GUO ning liu Qing XIN YunChang LUAN BaiFeng ZHOU zheng Department of Materials Science and Engineering Chongqing University Chongqing 400044 China

The microstructures of pearlitic steel wire rods and steel wires are commonly characterized by secondary electron imaging (SEI)technique using scanning electron microscopy(SEM).In this work,a back-scattered electron imaging(BSEI)method is proposed to determine the microstructures of undeformed and deformed pearlitic steels with nanometer scale pearlite *** results indicate that BSEI technique can characterize the pearlite lamellas veritably and is effective in quantitative measurement of the mean size of pearlite interlamellar *** some extent,BSEI method is more suitable than SEI technique for studying undeformed and not severely deformed pearlitic steels.

关键词： pearlitic steels microstructures back-scattered electron imaging (BSEI) cold drawing

High temperature mechanical retention characteristics and oxidation behaviors of the MoSi2（Cr5Si3）–RSiC composites prepared via a PIP-AAMI combined process

在线全文

学校读者我要写书评

暂无评论

Journal of Advanced Ceramics 2019年第2期8卷 196-208页

作者： Peng-zhao GAO Lei CHENG zheng YUAN Xiao-pan liu Han-ning XIAO College of Materials Science and Engineering Hunan UniversityChangsha 410082China Hunan Province Key Laboratory for Advanced Carbon Materials and Applied Technology Hunan UniversityChangsha 410082China Hunan Province Key Laboratory for Spray Deposition Technology and Application Hunan UniversityChangsha 410082China

In the present paper,MoSi2(Cr5Si3)–RSiC composites were prepared via a combination of precursor impregnation pyrolysis(PIP) and MoSi2-Si-Cr alloy active melt infiltration(AAMI) process. Composition, microstructure, mechanical retention characteristics, and oxidation behaviors of the composites at elevated temperature were studied. X-ray diffraction(XRD) pattern confirms that the composites mainly compose of 6 H–SiC, hexagonal MoSi2, and tetragonal Cr5Si3. Scanning electron microscopy(SEM) image reveals that nearly denseMoSi2(Cr5Si3)–RSiC composites exhibiting three-dimensionally(3D) interpenetrated network structure are obtained when infiltrated at 2173 K, and the interface combination of the composites mainly depends on the composition ratio of infiltrated phases. Oxidation weight gain rate of the composites is much lower than that of RSiC matrix, where MoSiCr2 possesses the lowest value of 0.1630 mg×cm-2, about 78% lower than that of RSiC after oxidation at 1773 K for 100 h. Also, it possesses the highest mechanical values of 139.54 MPa(flexural strength σf and RT) and 276.77 GPa(elastic modulus Ef and RT), improvement of 73.73% and 29.77% as compared with that of RSiC, respectively. Mechanical properties of the composites increase first and then decrease with the extension of oxidation time at 1773 K, due to the cooperation effect of surface defect reduction via oxidation reaction and thermal stress relaxation in the composites, crystal growth, and thickness increase of the oxide film. Fracture toughness of MoSiCr2 reaches 2.24 MPa·m1/2(1673 K), showing the highest improvement of 31.70% as compared to the RT value.

关键词： MoSi2(Cr5Si3)–RSiC composites precursor impregnation pyrolysis and MoSi2-Si-Cr alloy active melt infiltration (PIP-AAMI) high temperature mechanical characteristic oxidation behavior

Hot Deformation Behavior of GCr15 Steel

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2013年第3期20卷 50-56页

作者： PENG ning-qi TANG Guang-bo YAO Jun liu zheng-dong Institute for Structural Materials Central Iron and Steel Research Institute

Hot deformation behavior of GCr15（ASTM 52100） steel was investigated using single-hit compression tests on Gleeble-1500 simulator at the temperature range of 850-1 100 ℃ and strain rate range of 0.1-10 *** flow stress constitutive equation of GCr15 steel during hot deformation was determined by stress-strain curves analysis on the basis of the hyperbolic sine *** the models of dynamic recrystallization fraction and dynamic recrystallization grain size of GCr15 steel were established by the measured curves and microstructure observation in different experimental *** mean activation energy and the time exponent of dynamic recrystallization kinetics equation in the range of experimental conditions were determined to be 356.2 kJ/mol and 2.12,***,the flow stress model was also established by the method of allocating flow stress curve with three main stress values,the saturation stress,the steady state stress and the stress when strain is *** flow stress curves predicted by the developed models under different deformation conditions are in good agreements with the measured ones.

关键词： GCr15 steel hot deformation flow stress dynamic recrystallization