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Two-Sublattice Thermodynamic Model on Carbonitride Precipitation in Microalloyed Steels Bearing Nb-V-Ti

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Journal of Iron and Steel Research International 2011年第S1期18卷 271-277页

作者： XIANG Song 1,3,LIU Guo-quan 2.(1.School of Materials and Metallurgy,guizhou University,guiyang 550003,guizhou,china 2.School of Materials science and Engineering,University of science and Technology,Beijing,Beijing 100083,china 3.The Key Laboratory for Mechanical Behavior and Microstructure of Materials,guizhou Province,guiyang 550003,guizhou,china) guizhou Univ Sch Met & Mat Guiyang 550003 Guizhou Peoples R China Key Lab Mech Behav & Microstruct Mat Guiyang 550003 Guizhou Peoples R China Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China

Based on the two sublattice model of the regular solution,one being metal atom sublattice and another being interstitial atom sublattice,a thermodynamic model for the precipitates of niobium carbonitride,vanadium carbonitride and titanium carbonitride was established to study the starting-temperature of precipitates and the austenite compositions at given temperature in a low carbon *** calculation results show that starting-temperature of the precipitation of niobium carbonitride,vanadium carbonitride and titanium carbonitride are 1100℃,92.℃ and 1340℃,respectively,the mole fraction of carbonitride precipitates is 8.65×10-4 in the 0.053C-0.002.N-1.2.Mn-0.008S-0.031Al-0.046Nb-0.008Ti0.02.V-Fe *** the N content is from 0.002.% to 0.0056%,the starting-temperature of the precipitation of the titanium carbonitride changes from 1340℃ to 1430℃.And the C content is from 0.053% to 0.07%,the startingtemperature of the precipitation of the titanium carbonitride hardly changes,but the atomic fraction of niobium in the carbonitride obviously increases.

关键词： microalloyed steel carbonitride precipitation two sublattice model thermodynamics

First-principle study on the electronic structure of stressed CrSi_2

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science china(Physics,Mechanics & Astronomy) 2009年第1期52卷 76-81页

作者： ZHOU ShiYun1,2. XIE Quan1, YAN WanJun1 & CHEN Qian1 1 college of Electronic science & Information Technology, {2. University, guiyang 55002., china 2.Department of Physics, Anshun college, Anshun 561000, china college of Electronic science & Information Technology Guizhou University Guiyang China Department of Physics Anshun College Anshun China

The electronic structure of stressed CrSi2.was calculated using the first-principle methods based on plane-wave pseudo-potential theory. The calculated results showed that, under the uniaxial compression, the energy level of CrSi2.shifted toward high energy and its energy gap became wider with the increasing uniaxial stress, while the gap became narrower under the negative uniaxial stress. When the negative uniaxial stress was up to -18.5 GPa, CrSi2.was converted into a direct-gap semiconductor with the band gap of 0.32.eV.

关键词： CrSi2 first-principles stress electronic structure

First-principles study on the electronic structure and optical properties of CrSi_2

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science china(Physics,Mechanics & Astronomy) 2009年第1期52卷 46-51页

Using the first principle methods based on the plane-wave pseudo-potential theory, band structure, density of states and optical properties of CrSi2.were studied. The calculation of band structure shows that CrSi2.is an indirect semiconductor whose band gap is 0.353 eV. Density of states is mainly composed of 3d electron of Cr and 3p electron of Si. Dielectric function, refractive index, reflectivity, and absorption coefficient of CrSi2.are also calculated. The calculation results of optical properties are in agreement with the experiments.

关键词： CrSi2 electronic structure optical properties first principles

Study on Method of Fault Vibration Diagnose for Roller Overrunning Clutch

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厦门大学学报（自然科学版） 2002年第S1期41卷 216-217页

作者： LUO Yi-xin 1, DOU Yi-bing 2.(1. Department of Resources Engineering, Xiangtan Polytechnic Univers ity, Xiangtan 4112.1,china 2. guizhou University, {2. 55002., china)

Fault diagnose of the roller overrunning clutch is a headache problem in engineering at home and abroad. This paper introduces a new method to solve the problem by using the wavelet transform to separate fault si gnal and further analyzing the impact frequency. The signal local singularities under the wavelet transform are studied. According to the propagation features of modulus maximums of the fault signal and the noise under the wavelet transfor m different on the scales, and by use of the signal wavelet decomposition-recon struction algorithm, the clutch shell vibration acceleration signal is decompose d, denoised, and *** signal-to-noise of the monitored signal imp roved *** fault characteristic signal on time domain is *** f ault characteristic frequency is picked up. Experiment shows that it is quite effective.

关键词： clutch frequency fault diagnose

The radio structure of BL Lac object S5 2.07+777

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science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 187-190页

作者： WU ZhongZu1,3,GU MinFeng2.& CHEN YongJun2.1 college of science,{2. University,guiyang 55002.,china 2.Key Laboratory for Research in Galaxies and Cosmology,Shanghai Astronomical Observatory,Chinese Academy of sciences,Shanghai 2.0030,china 3 NAOC-GZU Sponsored Center for Astronomy,{2. University,guiyang 55002.,china college of science Guizhou University Guiyang China NAOC-GZU Sponsored Center for Astronomy Guizhou University Guiyang China Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai China

BL Lac object S5 2.07+777 has been classified as a HYMOR(Hybrid Morphology radio source) for its hybrid FR I and FR II radio *** is one of four BL Lac objects with a kpc scale extended X-ray *** this paper,we searched the unpublished European VLBI Network(EVN) archived high resolution data for this source,and present the high resolution radio *** EVN images all show a core-jet structure in 1.6,5 and 8 *** combination with the VLA data in the literature,we found position angle differences(△PA) of about 10°-2.° between pc and kpc scale jet *** brightness temperature estimated from multi-band EVN images are around 1011.2.1011.8 K,from which the Doppler factor ranges from 3.2.to *** found significant flux variations of the radio core in 1.6 and 5 GHz,from which we derived the variability in brightness temperature Tvar to be 1013.6 K and 1014.0 K,corresponding to the Doppler factors of 9.3 and 12.4,respectively.

关键词： active galactic nuclei VLBI BL Lac objects

Characteristics of rare earth elements in soils in guizhou carbonate region

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Chinese science Bulletin 1999年第S2期44卷 115-116页

作者： YAN Chongling~(1,2., HONG Yetang~1, WANG Shijie~1, FU Shunzhen~2. ZHU Keyong~2.and WU Shanqi~2.1. State Key Laboratory of Environmental Geochemistry, Chinese Academy of sciences, guiyang 550002. {2. 2. guizhou Institute of Environmental Protection, guiyang 550002. {2. State Key Laboratory of Environmental Geochemistry Chinese Academy of Sciences Guiyang 550002 China guizhou Institute of Environmental Protection Guiyang 550002 China

IN recent years, rare earth element (REE) being used in agriculture has gained greater progress and madeus reach some common views. The centent of REE (especially soluble REE) in soils has significantcorrelation with that of REE plant absorbed from soil. Therefore, it is very necessary to clarify contentvariation and background values of REE (especially soluble REE ) from the angles of relation of supplyand demand between soil and plants, for reasonably using REE and formulating relevant health standardin the region, avoiding excessive using REE and taking up soil environmental capacity of REE to result insoil or water-body polluted and sometime for researching rock weathering, soil-forming process and soilclassification in the region. This note deals with characteristics of content and distribution of REE andsoluble REE in soils of guizhou carbonate region.

关键词： rare earth element soil, Carbonate area, guizhou.

Constructed Mott-Schottky Heterostructure Catalyst to Trigger Interface Disturbance and Manipulate Redox Kinetics in Li-O_(2. Battery

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Nano-Micro Letters 2024年第12期16卷 42-58页

作者： Yongji Xia Le Wang guiyang Gao Tianle Mao Zhenjia Wang Xuefeng Jin Zheyu Hong Jiajia Han Dong-Liang Peng Guanghui Yue State Key Lab of Physical Chemistry of Solid Surface Fujian Key Laboratory of Surface and Interface Engineering for High Performance MaterialsCollege of MaterialsXiamen UniversityXiamen 361005People’s Republic of China

Lithium-oxygen batteries(LOBs)with high energy density are a promising advanced energy storage ***,the slow cathodic redox kinetics during cycling causes the discharge products to fail to decompose in time,resulting in large polarization and battery failure in a short ***,a self-supporting interconnected nanosheet array network NiCo_(2.O_(4)/MnO_(2.with a Mott-Schottky heterostructure on titanium paper(TP-NCO/MO)is ingeniously designed as an efficient cathode catalyst material for *** heterostructure can accelerate electron transfer and influence the charge transfer process during adsorption of intermediate by triggering the interface disturbance at the heterogeneous interface,thus accelerating oxygen reduction and oxygen evolution kinetics and regulating product decomposition,which is expected to solve the above *** meticulously designed unique structural advantages enable the TP-NCO/MO cathode catalyst to exhibit an astounding ultra-long cycle life of 800 cycles and an extraordinarily low overpotential of 0.73 *** study utilizes a simple method to cleverly regulate the morphology of the discharge products by constructing a Mott-Schottky heterostructure,providing important reference for the design of efficient catalysts aimed at optimizing the adsorption of reaction intermediates.

关键词： Mott-Schottky heterostructure Lithium-oxygen batteries Electrocatalysts Electrodeposition

Effect of Pb, Hg and Cd in soil on scavenging system of activated oxygen in tobacco leaves

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Chinese science Bulletin 1999年第S2期44卷 91-93页

作者： YAN Chongling~(1,2., HONG Yetang~1, WANG Shijie~1, LIN Peng~3, YANG Xianke~2. FU Shunzhen~2. ZHU Keyong~2.and WU Shanqi~2.1. State Key Laboratory of Environmental Geochemistry, Chinese Academy of sciences, guiyang 550002. {2. 2. guizhou Institute of Environmental Protection, guiyang 550002. {2. 3. Department of Biology, Xiamen University, Xiamen 361005, {2. State Key Laboratory of Environmental Geochemistry Chinese Academy of Sciences Guiyang 550002 China guizhou Institute of Environmental Protection Guiyang 550002 China Department of Biology Xiamen University Xiamen 361005 China

Pb, Hg and Cd will affect human health by vegetative chain. In recent years, people more and more are concerned about heavy metal pollution of the soil-plant system. Many researchers studied the effect of single heavy metal on growth, photosynthesis, respiration and quality of plants, but few systematicstudies of the effect of heavy metals on the scavenging system of activated oxygen of plants. This note systematically studies the effect of Pb, Hg and Cd in soil on the scavenging system of activated oxygen in tobacco leaves. 1 Material and methods Material: Tobacco (Nicoticana tabacum L). Methods: Cultivating and measuring methods were according to reference. 2.Results Results of this study indicate that the common effect of Pb, Hg and Cd on activity of CAT is obvi-

关键词： Pb Hg and Cd scavenging system of activated oxygen tobacco.

A restudy of Oryctocephalus indicus (Reed,1910)

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Progress in Natural science:Materials International 2006年第11期16卷 1177-1182页

作者： ZHAO Yuanlong~1**, YUAN Jinliang~2. PENG Shanchi~ 2.3 , YANG Xinglian~1, PENG Jin~1, LIN Jihpai~4, and GUO Qingjun~5(1. college of Resource and Environment of guizhou University, {2. 550003, china 2. Nanjing Institute of Geology and Palaeontology, Chinese Academy of sciences, Nanjing 2.0008, china 3. State Key Laboratory of Papaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Nanjing 2.0008, china 4. Department of Geological science, Ohio State University, Columbus, OH 432.0, USA 5. Institute of Geochemistry, Chinese Academy of sciences, {2. 550002. china) college of Resource and Environment of guizhou University Guiyang 550003 China Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China State Key Laboratory of Papaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Nanjing 210008 China Department of Geological science Ohio State University Columbus OH 43210 United States Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Restudy on morphology of Oryctocephalus indicus (Reed, 1910), based on specimens from guizhou, china and Nevada USA, suggests that the subspecies regarded previously as Oryctocephalus indicus indicus (Reed, 1910), O. indicus latus Zhao et Yuan 2.02. and O. indicus kobayashi Saito, 1934, are synonymous, and Oryctocephalus americanus Sundberg et McCollum, 2.03 is a similar form of O. indicus. Oryctocephalus indicus is rediagnosed as having a glabella that is subconical in outline and tapering forward slightly; a thorax that comprises 12.segments, and a small pygidium that bears 2.3 axial rings with a terminal piece and a postaxial ridge. Oryctocephalus indicus is widely distributed in eastern guizhou and ranges through a great interval of Kaili Formation. Its first appearance is almost identical with these events of trilobite extinction-recovery occurring at the end of the Early Cambrian, the alternation of acritach assemblages, the change of trace elements (REE) and stable isotopes (carbon) at the Wuliu-Zengjiaya section. As one of the key forms for defining the traditional Lower-Middle Cambrian boundary (the base of Cambrian Series 3 and Stage 5 in the new Cambrian chronstratigraphic standard), O. indicus has received detailed study and has more advantages than other species such as Ovatoryctocara granulata Tchernysheva, 1962.or Arthricocephalus chauveaui Bergeron, 1899.

关键词： Oryctocephalus indicus restudy Kaili Formation Cambrian guizhou china.