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“合作”的词汇化——兼论现代汉语中“合V”类谓词的形成
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作者 黄瓒辉 《语言教学与研究》 CSSCI 北大核心 2019年第6期88-100,共13页
本文分析"合作"的词汇化过程,同时讨论现代汉语中"合V"类谓词的形成。本文认为"合作"成词的年代较晚,在明清时期完成其由短语到词的演变过程。在"合作"由短语到词的发展过程中,"作"... 本文分析"合作"的词汇化过程,同时讨论现代汉语中"合V"类谓词的形成。本文认为"合作"成词的年代较晚,在明清时期完成其由短语到词的演变过程。在"合作"由短语到词的发展过程中,"作"表示的具体行为动作义逐渐减弱是其发展的关键。本文详细描述了促成"作"的具体行为动作义减弱的语境条件。对于现代汉语中相对开放的"合V"类谓词的形成,本文认为部分是汉语史上已有"合V"的重新分析所得,部分则是已有"合V"组合的结构类推而致;而语义指向上的变化则跟汉语语序演变的整体格局是一致的。 展开更多
关键词 “合作” 词汇化 “合v” 性谓词 重新分析 类推
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Effect of Ti-Mo-V composite addition on microstructure andmechanical properties of marine 10Ni5CrMoV steel
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作者 ZOU Tao DONG Yan-wu +3 位作者 JIANG Zhou-hua WANG Qi WANG Yong PENG Fei 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第10期3628-3645,共18页
The effects of Ti-Mo-V composite addition on the evolution of precipitates in marine 10Ni5CrMoV steel andthe corresponding strength and toughness mechanisms were systematically investigated.Ti-Mo-V composite addition ... The effects of Ti-Mo-V composite addition on the evolution of precipitates in marine 10Ni5CrMoV steel andthe corresponding strength and toughness mechanisms were systematically investigated.Ti-Mo-V composite addition canform the Ti_(x)Mo_(y)V_(z)C carbide with TiC as core and Mo-V as shell in the order of Ti(C)→V→Mo.The yield strength of thespecimens is increased from 815 MPa to 876 MPa due to the nanoscale precipitates enhancing the pinning effect on grainboundaries and dislocations,and the contribution of precipitation and dislocation strengthening is increased.The decrease of ductile-brittle transition temperature from−103 to−116℃is attributed to the decrease in equivalent grainsize and the increase of high-angle grain boundary misorientation,which hinders the initiation and propagation of cracks.When the mass fraction of Ti is 0.05%,the strength and cryogenic toughness can be improved synergistically,which alsoprovides a theoretical basis and experimental reference for exploring the more excellent combination of strength andcryogenic toughness of marine 10Ni5CrMoV steel. 展开更多
关键词 10Ni5CrMov steel Ti-Mo-v composition addition ductile-brittle transition temperature Ti_(x)Mo_(y)v_(z)C mechanical properties
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Cryogenic springback of 2219-W aluminum alloy sheet through V-shaped bending
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作者 Xiao-bo FAN Qi-liang WANG +1 位作者 Fang-xing WU Xu-gang WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第10期3185-3193,共9页
A V-shaped bending device was established to evaluate the effects of temperature and bending fillet radius on springback behavior of 2219-W aluminum alloy at cryogenic temperatures.The cryogenic springback mechanism w... A V-shaped bending device was established to evaluate the effects of temperature and bending fillet radius on springback behavior of 2219-W aluminum alloy at cryogenic temperatures.The cryogenic springback mechanism was elucidated through mechanical analyses and numerical simulations.The results indicated that the springback angle at cryogenic temperatures was greater than that at room temperature.The springback angle increased further as the temperature returned to ambient conditions,attributed to the combined effects of the “dual enhancement effect” and thermal expansion.Notably,a critical fillet radius made the springback angle zero for 90° V-shaped bending.The critical fillet radius at cryogenic temperatures was smaller than that at room temperature,owing to the influence of temperature variations on the bending moment ratio between the forward bending section at the fillet and the reverse bending section of the straight arm. 展开更多
关键词 2219-W aluminum alloy cryogenic forming v-shape bending SPRINGBACK critical fillet radius
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Phase-field study on competition precipitation process of Ni-Al-V alloy 被引量:5
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作者 卢艳丽 卢广明 +1 位作者 贾德伟 陈铮 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第2期544-551,共8页
With microscopic phase-field kinetic model, atomic-scale computer simulation program for the precipitation sequence and microstructure evolution of the ordered intermetallic compound γ' and θ in ternary Ni75AlxV25-... With microscopic phase-field kinetic model, atomic-scale computer simulation program for the precipitation sequence and microstructure evolution of the ordered intermetallic compound γ' and θ in ternary Ni75AlxV25-x alloy were studied. The simulation results show that Al concentration has important effects on the precipitation sequence. When Al concentration in Ni75AlxV25-x alloy is low, 0(Ni3V) ordered phase will be firstly precipitated, followed by γ'(Ni3Al) ordered phase. With Al concentration increasing, θ and γ' ordered phases are simultaneously precipitated. With A1 concentration further increasing, γ' ordered phase is firstly precipitated, followed by θ ordered phase. There is a competition relationship between θ and γ' ordered phases during growth and coarsening process. No matter which first precipitates, θ ordered phase always occupies advantage in the competition process of coarsening, thus, the microstructure with preferred orientation is formed. 展开更多
关键词 Ni-Al-v alloy microstructure evolution precipitation process phase-field method
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Arrhenius-type constitutive model and dynamic recrystallization behavior of V-5Cr-5Ti alloy during hot compression 被引量:9
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作者 李鱼飞 王震宏 +2 位作者 张林英 罗超 赖新春 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第6期1889-1900,共12页
To clarify the high temperature flow stress behavior and microstructures evolution of a V-5Cr-5Ti (mass fraction, %) alloy, the isothermal hot compression tests were conducted in the temperature range of 1423-1573 K... To clarify the high temperature flow stress behavior and microstructures evolution of a V-5Cr-5Ti (mass fraction, %) alloy, the isothermal hot compression tests were conducted in the temperature range of 1423-1573 K with strain rates of 0.01, 0.1, and 1 s-1. The results show that the measured flow stress should be revised by friction and the calculated values of friction coefficient m are in the range of 0.45-0.56. Arrhenius-type constitutive equation was developed by regression analysis. The comparison between the experimental and predicted flow stress shows that the R~ and the average absolute relative error (AARE) are 0.948 and 5.44%, respectively. The measured apparent activation energy Qa is in the range of 540-890 kJ/mol. Both dis-continuous dynamic recrystallization (DDRX) and continuous dynamic recrystallization (CDRX) mechanisms are observed in the deformed alloy, but dynamic recovery (DRV) is the dominant softening mechanism up to a true strain of 1.5. 展开更多
关键词 v-5Cr-5Ti alloy constitutive model flow stress dynamic recrystallization
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Preparation of V-Ti-Fe master alloys by metallothermic reduction method 被引量:5
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作者 王斌 刘奎仁 +2 位作者 陈建设 高腾跃 何季麟 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第6期1507-1512,共6页
V-Ti-Fe master alloys were prepared by metaUothermic reduction method, and the influences of the mass ratio of V205 to TiO2, Al and Al-Mg alloy addition amounts on the metal recovery rates and alloy compositions were ... V-Ti-Fe master alloys were prepared by metaUothermic reduction method, and the influences of the mass ratio of V205 to TiO2, Al and Al-Mg alloy addition amounts on the metal recovery rates and alloy compositions were investigated. The results show that appropriate technological parameters are: the mass ratio of V205 to TiO2 is 0.5:1, Al addition represents 95% of the theoretical value, and the Al-Mg alloy addition amount is one third that of the Al addition. The results from energy spectrum analysis show that V and Fe distribute uniformly in the prepared alloy, while the segregation for Ti, i.e. Ti-rich phase is detected. A spray refming process was carried out to reduce the impurity contents of Al and O in the prepared alloys. The Al content drops from 4.27% to 1.86%, and the O content drops from 2.10% to 0.91% after the refining process. 展开更多
关键词 v-Ti-Fe master alloys metallothermic reduction method recovery rates refining process
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Thermal activation parameters of V-5Cr-5Ti alloy under hot compression
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作者 李鱼飞 王震宏 +2 位作者 周运洪 罗超 赖新春 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第8期2564-2570,共7页
In order to well understand the elementary mechanisms that govern the hot working process of a V?5Cr?5Ti alloy (mass fraction, %), thermal activation parameters under compression were measured in a temperature ran... In order to well understand the elementary mechanisms that govern the hot working process of a V?5Cr?5Ti alloy (mass fraction, %), thermal activation parameters under compression were measured in a temperature range of 1373?1673 K by a Gleeble?3800 system. The results show that the stress exponentn is 4.87 and the activation energyQis 375.89 kJ/mol for the power law equation. The activation energy is determined as 288.34 kJ/mol, which is close to the self-diffusion energy of alloy (270?300 kJ/mol) by introducing a threshold stress(σ0) variable. The typical values of physical activation volume (Vp) and strain rate sensitivity (m) are measured as (120?700)b3 and 0.075?0.122, respectively, by the repeated stress relaxation tests. These activation parameters indicate that the rate controlling mechanism for V?5Cr?5Ti alloy compressed in ranges of 1373?1673 K and 0.001?1.0 s?1 is the dislocation climb by overcoming of forest dislocations. 展开更多
关键词 v-5Cr-5Ti alloy hot compression thermal activation dislocation climb
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Springback analysis of 6016 aluminum alloy sheet in hot V-shape stamping 被引量:11
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作者 MA Wei-ping WANG Bao-yu +2 位作者 XIAO Wen-chao YANG Xiao-ming KANG Yi 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第3期524-535,共12页
Springback behavior of 6016 aluminum alloy in hot stamping was investigated by a series of experiments under different conditions using V-shape dies and a finite element model which was validated reliable was used to ... Springback behavior of 6016 aluminum alloy in hot stamping was investigated by a series of experiments under different conditions using V-shape dies and a finite element model which was validated reliable was used to further elucidate the springback mechanism. The effects of initial blank temperature, blank-holding force, die closing pressure and die corner radius were studied. It is found that springback decreases remarkably as the initial blank temperature rises up to 500 °C. The springback also reduces with the increase of die holding pressure and the decrease of die corner radius. Under different initial temperatures, the influence of blank-holding force is distinct. In addition, the bending and straightening of the side wall during the stamping process is found to interpret the negative springback phenomenon. 展开更多
关键词 SPRINGBACK hot stamping 6016 aluminum alloy v-shape stamping
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Microstructure and hydrogen storage properties of as-cast and rapidly solidified Ti-rich Ti-V alloys 被引量:3
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作者 Suwarno SUWARNO Jan Ketil SOLBERG +7 位作者 Jan Petter MAEHLEN Bente KROGH Bφrre Tore BφRRESEN Esther OCHOA-FERNANDEZ Erling RYTTER Mario WILLIAMS Roman DENYS Volodymyr A.YARTYS 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第8期1831-1838,共8页
The goal of the present work was to optimize the phase-structural composition and microstructure of binary Ti0.8-0.9V0.2-0.1 alloys with respect to their hydrogen sorption properties. Application of these alloys is fo... The goal of the present work was to optimize the phase-structural composition and microstructure of binary Ti0.8-0.9V0.2-0.1 alloys with respect to their hydrogen sorption properties. Application of these alloys is for hydrogen absorption from gaseous mixtures containing substantial amounts of carbon monoxide (CO) at high temperatures. Irrespective of alloy composition, both α(HCP) and β(BCC) phases in Ti0.8-0.9V0.2-0.1 formed single phase FCC hydrides upon hydrogenation in pure H2. An in situ synchrotron X-ray diffraction study showed that only the β-phase transformed to the corresponding hydride when the alloy was hydrogenated in a mixture of H2+10%CO. Rapid solidification (RS) of the alloy resulted in refined grain sizes both in the Ti0.8V0.2 and Ti0.9V0.1 alloys. Furthermore, RS was found to increase the β-phase fraction in Ti0.9V0.1, being twice larger than that of the as-cast alloy. Ti0.9V0.1 had a platelike microstructure as observed by scanning electron microscopy (SEM), the plates were about 300 nm thick. The microstructure refinement resulted in a faster kinetics of H desorption as observed by temperature desorption spectroscopy (TDS). 展开更多
关键词 hydrogen storage Ti-v alloys rapid solidification synchrotron X-ray diffraction carbon monoxide
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DETECTION OF B LYMPHOMA CELLS UNDERGOING APOPTOSIS BY ANNEXIN-V ASSAY 被引量:6
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作者 彭黎明 江虹 Chris Bradely 《Chinese Medical Sciences Journal》 CAS CSCD 2002年第1期17-21,共5页
To quantitatively analyze apoptotic and secondary necrotic cells unde r apoptosis conditions. Methods. The cells of Burkitt lymphoma (BL) cell line Raji were incubated with 1 .0 μmol/L dexamethasone (DEX) for 2, 4 an... To quantitatively analyze apoptotic and secondary necrotic cells unde r apoptosis conditions. Methods. The cells of Burkitt lymphoma (BL) cell line Raji were incubated with 1 .0 μmol/L dexamethasone (DEX) for 2, 4 and 8 h respectively, then stained with Annexin V FITC (fluorescein isothiocyanate conjugated) which was used to detec t the exposed phosphatidylserine (PS) on the epimembrane resulting from a loss o f phospholipid asymmetry in the early stage of apoptosis, and also stained with propidium iodide (PI) which allows analysis of secondary necrotic cells related with cell membrane and DNA damage that probably represent late stage of apoptosi s, then apoptotic cells were quantified by flow cytometry (FCM). Furthermore, An nexin+/PI and Annexin+/PI+ cells were sorted by fluoresence activated cell sorter (FACS), and identified by electron microscopy (EM) and DNA gel electroph oresis. Results. The percentage of apoptotic cells was found to increase with the incuba tion time (r=0.97). This method was sensitive with low detection limit (0.02%), and was reproducible with low coefficient variance (CV)(4.2%). Meanwhile, the Annexin+/PI and Annexin+/PI+ cells were identified as apoptotic and necroti c cells under EM, and DNA extracted from the Annexin+/PI cells was characteri zed by “ladder pattern”. Conclusions. Annexin V assay is a specific, sensitive, accurate, reproductive and quantitative method for analyzing apoptotic cells. 展开更多
关键词 APOPTOSIS annexin v flow cytometry
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Microstructural evolution and mechanical properties of selective laser melted Ti-6Al-4V induced by annealing treatment 被引量:4
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作者 WANG Pei CHEN Feng-hua +3 位作者 J.ECKERT S.PILZ S.SCUDINO K.G.PRASHANTH 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第4期1068-1077,共10页
Ti-6Al-4V specimens were fabricated by selective laser melting(SLM)to study the effect of thermal treatment on the phase transformation,elemental diffusion,microstructure,and mechanical properties.The results show tha... Ti-6Al-4V specimens were fabricated by selective laser melting(SLM)to study the effect of thermal treatment on the phase transformation,elemental diffusion,microstructure,and mechanical properties.The results show that vanadium enriches around the boundary ofαphases with increasing annealing temperature to 973 K,andα′phases transform intoα+βat 973 K.The typicalα′martensite microstructure transforms to fine-scale equiaxed microstructure at 973 K and the equiaxed microstructure significantly coarsens with increasing annealing temperature to 1273 K.The SLM Ti-6Al-4V alloy annealed at 973 K exhibits a well-balanced combination of strength and ductility((1305±25)MPa and(37±3)%,respectively). 展开更多
关键词 selective laser melting TI-6AL-4v annealing treatment MICROSTRUCTURE mechanical properties
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Evolution of V-containing phases during preparation of Al-based Al−V master alloys 被引量:1
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作者 Yi MENG Yue YANG +4 位作者 Cen LI Lei-gang CAO Zhi-hao ZHAO Qing-feng ZHU Jian-zhong CUI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第7期2110-2124,共15页
Al-based Al−V master alloys were prepared by both the stepwise heating melting experiment and stepwise melting cooling experiment with rapid solidification to investigate the transformation of V-containing phases whic... Al-based Al−V master alloys were prepared by both the stepwise heating melting experiment and stepwise melting cooling experiment with rapid solidification to investigate the transformation of V-containing phases which gave different effects on microstructures and properties of commercial Al alloys and Ti alloys,as both melting and solidification processes affect the evolution of V-containing phases largely.The results showed that the raw Al−50wt.%V alloy consisted of needle-like Al_(3)V phase and Al8V5 phase(matrix),while petal-like Al_(3)V,needle-like Al_(7)V and plate-like Al_(10)V phase were present in the Al−V master alloys.The metastable Al_(7)V phase was evolved from Al_(3)V phase and then evolved into Al_(10)V phase during melting process.The number of Al_(10)V phase increased with the decrease of temperature in the range of 800−1000℃.Petal-like Al_(3)V phases could be transformed from Al_(8)V_(5) phase,pre-precipitated from Al−V molten liquid during melting process and precipitated directly during rapid solidification,respectively. 展开更多
关键词 Al-based Al−v master alloy phase transformation vanadium-containing phase rapid solidification pouring temperature
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Synthesis and Structural Characterization of [(C_2H_5)_4N][V^((V))O_2(OC_6H_3(OCH_3)CHNNCSNH_2)]·H_2O 被引量:1
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作者 周荫庄 金祥林 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第4期249-252,共4页
The reaction of tetraethylammonium metavanadate, (Et4N)VO3, with isovanillin semithiocarbazone(VSTC), HOC6H3(OCH3)CH=NNHCSNH2, in a mixed solvent of ethanol, water and DMSO yields the mononuclear dioxovanadate(... The reaction of tetraethylammonium metavanadate, (Et4N)VO3, with isovanillin semithiocarbazone(VSTC), HOC6H3(OCH3)CH=NNHCSNH2, in a mixed solvent of ethanol, water and DMSO yields the mononuclear dioxovanadate(V) complex, [(C2H5)4N][V(V)O2 (OC6H3- (OCH3)CHNNCSNH2)](H2O (C17H31N4O5SV, Mr = 454.5) and its single-crystal structure has been determined by X-ray diffraction. The crystal belongs to orthorhombic space group P212121 with unit cell parameters a = 12.940(3), b= 15.414(3), c = 10.703(2) ?, V = 2134.8(11) ?3, Z=4, Dcalc = 1.414 Kg/m3, ( = 0.597 mm-1, and F(000) = 960. The final agreement factors are R = 0.076 and Rw=0.096 for 1600 observed independent reflections with F ≥4.0((F). The structure revealed that the vanadium atom is bound to two terminal oxygen atoms and one tridentate donor ligand in a distorted square pyramidal arrangement. The sulphur-nitrogen-oxygen donor Schiff-base ligand in the thiol form rather than the thione form is coordinated to the vanadium via the mercapto sulphur, the (-nitrogen and the hydroxylate oxygen. 展开更多
关键词 vanadium(v) complex sulphur-oxygen-nitrogen donor Schiff-base isovanillin semithiocarbazone crystal structure
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Microstructures and mechanical properties of Ti−Al−V−Nb alloys with cluster formula manufactured by laser additive manufacturing 被引量:10
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作者 Tian-yu LIU Xiao-hua MIN +2 位作者 Shuang ZHANG Cun-shan WANG Chuang DONG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第10期3012-3023,共12页
Ti−Al−V−Nb alloys with the cluster formula,12[Al−Ti_(12)](AlTi_(2))+5[Al−Ti1_(4)](V,Nb)2Ti,were designed by replacing V with Nb based on the Ti−6Al−4V alloy.Single-track cladding layers and bulk samples of the alloys ... Ti−Al−V−Nb alloys with the cluster formula,12[Al−Ti_(12)](AlTi_(2))+5[Al−Ti1_(4)](V,Nb)2Ti,were designed by replacing V with Nb based on the Ti−6Al−4V alloy.Single-track cladding layers and bulk samples of the alloys with Nb contents ranging from 0 to 6.96 wt.%were prepared by laser additive manufacturing to examine their formability,microstructure,and mechanical properties.For single-track cladding layers,the addition of Nb increased the surface roughness slightly and decreased the molten pool height to improve its spreadability.The alloy,Ti−5.96Al−1.94V−3.54Nb(wt.%),exhibited better geometrical accuracy than the other alloys because its molten pool height was consistent with the spread layer thickness of the powder.The microstructures of the bulk samples contained similar columnar β-phase grains,regardless of Nb content.These grains grew epitaxially from the Ti substrate along the deposition direction,with basket-weaveα-phase laths within the columnar grains.Theα-phase size increased with increasing Nb contents,but its uniformity decreased.Along the deposition direction,the Vickers hardness increased from the substrate to the surface.The Ti−5.96Al−1.94V−3.54Nb alloy exhibited the highest Vickers hardness regardless of deposition position because of the optimal matching relationship between theα-phase size and its content among the designed alloys. 展开更多
关键词 Ti−Al−v−Nb alloy composition design laser additive manufacturing microstructure mechanical properties
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Microstructural aspects of in-situ TiB reinforced Ti-6Al-4V composite processed by spark plasma sintering 被引量:4
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作者 Saeid GHESMATI TABRIZI Abolfazl BABAKHANI +1 位作者 Seyed Abdolkarim SAJJADI 吕维洁 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第5期1460-1467,共8页
Titanium-matrix composites have important and wide applications in the transport and aerospace industries. The current research was focused on powder metallurgy processing of in-situ reinforced titanium-matrix composi... Titanium-matrix composites have important and wide applications in the transport and aerospace industries. The current research was focused on powder metallurgy processing of in-situ reinforced titanium-matrix composite with Ti B whiskers. The Ti-6Al-4V alloy and B4 C additive powders were used as raw materials. Two different consolidation techniques, namely press-and-sintering and spark plasma sintering, were selected. It was observed that in-situ Ti B whiskers were formed during sintering in both methods. The changes in size, aspect ratio and distribution of in-situ whiskers in different composite samples were monitored. The effect of spark plasma sintering temperature on the synthesis of in-situ whiskers was also investigated. Based on the microstructural observations(optical microscopy and scanning electron microscopy) and the energy dispersive spectroscopy analysis, it was concluded that increasing the spark plasma sintering temperature from 900 to 1100 °C would lead to the complete formation of in-situ Ti B whiskers and reduced porosity content. 展开更多
关键词 Ti-6Al-4v metal matrix composite TiB whisker in-situ reaction spark plasma sintering
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Nd:YAG laser micro-welding of ultra-thin FeCo-V magnetic alloy:optimization of weld strength 被引量:1
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作者 H.MOSTAAN M.SHAMANIAN +2 位作者 S.HASANI M.SAFARI J.A.SZPUNAR 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第8期1735-1746,共12页
The main aim of this research is to optimize the tensile strength of laser welded FeCo-V alloy.A mathematicalrelationship was developed to predict tensile strength of the laser beam welded FeCo-V foils by incorporatin... The main aim of this research is to optimize the tensile strength of laser welded FeCo-V alloy.A mathematicalrelationship was developed to predict tensile strength of the laser beam welded FeCo-V foils by incorporating process parameterssuch as lamping current,welding speed,pulse duration and focused position.The procedure was established to improve the weldstrength and increase the productivity.The results indicate that the pulse duration and welding speed have the greatest influence ontensile strength.The obtained results showed that the tensile strength of the weld joints increase as a function of increasing pulseduration reaching to a maximum at a pulse duration value of2.25ms.Moreover,the tensile strength of joints increases with decreasein welding speed reaching to a maximum at a welding speed of125mm/min.It has been shown that increase in pulse duration anddecrease in welding speed result in increased effective peak power density and hence formation of more resistant welds.At higherpulse durations and lower welding speeds,the tensile strength of weld joints decreases because of formation of solidificationmicrocracks in the fusion zone. 展开更多
关键词 Nd:YAG laser welding FeCo-v magnetic alloys response surface methodology mechanical properties OPTIMIZATION
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Effect of Salinity on the Biosynthesis of Amines in Litopenaeus vannamei and the Expression of Gill Related Ion Transporter Genes 被引量:5
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作者 PAN Luqing LIU Hongyu ZHAO Qun 《Journal of Ocean University of China》 SCIE CAS 2014年第3期453-459,共7页
This study examined the effect of salinity on the expression of Na+/K+-ATPase(NKA) α-subunit and vacuolar-type H+-ATPase(V-ATPase) β-subunit gene in the gill of Litopenaeus vannamei. Semi-quantitative reverse transc... This study examined the effect of salinity on the expression of Na+/K+-ATPase(NKA) α-subunit and vacuolar-type H+-ATPase(V-ATPase) β-subunit gene in the gill of Litopenaeus vannamei. Semi-quantitative reverse transcription-polymerase chain reaction(RT-PCR) assay showed that the expression of NKA α-subunit and V-ATPase β-subunit gene was significantly influenced by salinity. It was found that the NKA activity significantly varied with salinity in time and dose dependent manner; whereas the V-ATPase activity did not. The abundance of NKA α-subunit gene transcript increased rapidly when the salinity decreased from 26 b to 21, and slowly when the salinity decreased from 26 to 31 within the first 24 h. When the salinity decreased from 26 to 21, the transcription of NKA α-subunit gene in gill epithelium was higher at 12 h than that at 0 h, which was consistent with the result of immunoblotting assay of NKA α-subunit. In addition, salinity had a significant time- and dose-dependent effect on the concentration of biogenic amines in both hemolymph and gill. As compared to other parameters, the concentration of dopamine(DA) and 5-hydroxytryptamine(5-HT) varied in different patterns when the salinity decreased from 26 to 21 or increased from 26 to 31, suggesting that DA and 5-HT played different regulatory roles in osmotic adaption and modulation of shrimp when salinity varies. 展开更多
关键词 SALINITY Litopenaeus vannamei biogenic amine Na^+/K^+-ATPase v-ATPASE
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Cellular automaton simulation of dynamic recrystallization behavior in V-10Cr-5Ti alloy under hot deformation conditions 被引量:5
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作者 Zhuo-han CAO Yu SUN +4 位作者 Chen ZHOU Zhi-peng WAN Wen-hua YANG Li-li REN Lian-xi HU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第1期98-111,共14页
The deformation behavior of V-10Cr-5Ti alloy was studied on the Gleeble-1500 thermomechanical simulator at the temperatures of 950-1350℃, and the strain rates of 0.01-10 s^-1. Based on the Arrhenius model, dislocatio... The deformation behavior of V-10Cr-5Ti alloy was studied on the Gleeble-1500 thermomechanical simulator at the temperatures of 950-1350℃, and the strain rates of 0.01-10 s^-1. Based on the Arrhenius model, dislocation density model, nucleation model and grain growth model, a numerical cellular automaton (CA) model coupling simulation of hot deformation is established to simulate and characterize the microstructural evolution during DRX. The results show that the flow stress is fairly sensitive to the strain rate and deformation temperature. The error between the predicted stress by the Arrhenius model and the actual measured value is less than 8%. The initial average grain size calculated by the CA model is 86.25 μm, which is close to the experimental result (85.63 μm). The simulations show that the effect of initial grain size on the dynamic recrystallization microstructure evolution is not significant, while increasing the strain rate or reducing the temperature can refine the recrystallized grains. 展开更多
关键词 v-10Cr-5Ti alloy hot deformation dynamic recrystallization cellular automaton MICROSTRUCTURE numerical simulation grain refinement
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Time-resolved Photoluminescence Spectra of Nominally Disordered GaInP Alloy
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作者 LUYi-jun GAOYu-lin 《Semiconductor Photonics and Technology》 CAS 2002年第1期22-26,共5页
Luminescence decay and time resolved photoluminescence(TRPL) spectra are used for study on the transient luminescence process of the nominally disordered GaInP alloy. The luminescence decay of GaInP alloy shows the te... Luminescence decay and time resolved photoluminescence(TRPL) spectra are used for study on the transient luminescence process of the nominally disordered GaInP alloy. The luminescence decay of GaInP alloy shows the temperature and excitation intensity dependent characters. At 77 K and under high excitation intensity, the luminescence decay shows single exponential time dependence, while under low excitation intensity or at 300 K, the luminescence decay shows double exponential time dependence. The analysis indicates that this nominally disordered GaInP alloy actually exhibits a very weak degree of order. The blue shift of PL peak is observed in the TRPL spectra at 77 K, which is derived from the transfer of the carriers from the ordered domain to the disordered region of the alloy. At 300 K, due to the thermal quenching, the transfer is too weak to be observed. However, The recombination of the carriers between the ordered domain and the disordered region is still devoted to luminesce. 展开更多
关键词 LUMINESCENCE Disordered alloy III-v semiconductor
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Syntheses,Structures and Characterizations of Two New Vanadium(V) Complexes:[PyH][V^VO_2(C_(14)H_9N_2O_3Br)] and [V^VO(C_(14)H_9N_2O_3Br)(OCH_3)] 被引量:1
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作者 ZHANGXiu-Tang ZHANXiao-Ping 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2002年第6期629-633,共5页
The new oxovanadium (V) complex, [PyH][VO2(L)] 1 (salicyladehyde 5-bromo salicyloylhydrazone is abbreviated as H2L; Hpy is protonated pyridine) was obtained from a refluxed solution of VOSO4 and H2L in acetonitrile-me... The new oxovanadium (V) complex, [PyH][VO2(L)] 1 (salicyladehyde 5-bromo salicyloylhydrazone is abbreviated as H2L; Hpy is protonated pyridine) was obtained from a refluxed solution of VOSO4 and H2L in acetonitrile-methanol-pyridine. Similarly, another new complex, [VO(L)(OCH3)] 2 was synthesized by refluxing VOSO4 and H2L in methanol-pyridine. Crystal data for 1: C19H15N3O5BrV, Mr= 496.2, monoclinic, P21/n, a = 7.1885(3), b = 9.2718(3), c = 28.803(1) A, β = 96.185(1)°, Z = 4 and V = 1908.6(1) A3; for 2: C15H12N2O5BrV, Mr= 431.1, monoclinic, P2,/n, a = 12.202(2), b = 8.045(2), c = 16.604(3) A, β = 101.29(3)°, Z = 4 and V = 1598.4(2) A3. The structures of 1 and 2 have been determined by X-ray analyses and reveal that the coordination environments of V atoms in both complexes are of square-based pyramid. Three of the four based donor atoms are from the tridentate 'ONO' donor ligand while the fourth is one terminal oxygen atom with the V(1) - O(3) distance 1.646(4) A for 1 and one -OCH3 group with the V(1)-O(3) distance 1.753(3) A for 2. The V(1)-O(4) terminals occupy the axial sites in both cases. The complexes are also characterized by IR and 1H NMR spectroscopies. 展开更多
关键词 salicyladehyde 5-bromo salicyloylhydrazone vanadium (v) complex crystal structure
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