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Formation of Tianwen-1 landing crater and mechanical properties of Martian soil near the landing site 被引量:1
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作者 Xinshuo Chen Zhaobin Zhang +7 位作者 Juan Li Shouding Li Tao Xu Bo Zheng Xiukuo Sun Yanfang Wu Yiming Diao Xiao Li 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第9期1293-1303,共11页
After landing in the Utopia Planitia,Tianwen-1 formed the deepest landing crater on Mars,approximately 40 cm deep,exposing precious information about the mechanical properties of Martian soil.We established numerical ... After landing in the Utopia Planitia,Tianwen-1 formed the deepest landing crater on Mars,approximately 40 cm deep,exposing precious information about the mechanical properties of Martian soil.We established numerical models for the plume-surface interaction(PSI)and the crater formation based on Computational Fluid Dynamics(CFD)methods and the erosion model modified from Roberts’Theory.Comparative studies of cases were conducted with different nozzle heights and soil mechanical properties.The increase in cohesion and internal friction angle leads to a decrease in erosion rate and maximum crater depth,with the cohesion having a greater impact.The influence of the nozzle height is not clear,as it interacts with the position of the Shock Diamond to jointly control the erosion process.Furthermore,we categorized the evolution of landing craters into the dispersive and the concentrated erosion modes based on the morphological characteristics.Finally,we estimated the upper limits of the Martian soil’s mechanical properties near Tianwen-1 landing site,with the cohesion ranging from 2612 to 2042 Pa and internal friction angle from 25°to 41°. 展开更多
关键词 Tianwen-1 Plume-surface interaction Landing crater formation Martian soil mechanical properties Numerical simulation
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Transforming growth factor-beta 1 enhances discharge activity of cortical neurons
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作者 Zhihui Ren Tian Li +5 位作者 Xueer Liu Zelin Zhang Xiaoxuan Chen Weiqiang Chen Kangsheng Li Jiangtao Sheng 《Neural Regeneration Research》 SCIE CAS 2025年第2期548-556,共9页
Transforming growth factor-beta 1(TGF-β1)has been extensively studied for its pleiotropic effects on central nervous system diseases.The neuroprotective or neurotoxic effects of TGF-β1 in specific brain areas may de... Transforming growth factor-beta 1(TGF-β1)has been extensively studied for its pleiotropic effects on central nervous system diseases.The neuroprotective or neurotoxic effects of TGF-β1 in specific brain areas may depend on the pathological process and cell types involved.Voltage-gated sodium channels(VGSCs)are essential ion channels for the generation of action potentials in neurons,and are involved in various neuroexcitation-related diseases.However,the effects of TGF-β1 on the functional properties of VGSCs and firing properties in cortical neurons remain unclear.In this study,we investigated the effects of TGF-β1 on VGSC function and firing properties in primary cortical neurons from mice.We found that TGF-β1 increased VGSC current density in a dose-and time-dependent manner,which was attributable to the upregulation of Nav1.3 expression.Increased VGSC current density and Nav1.3 expression were significantly abolished by preincubation with inhibitors of mitogen-activated protein kinase kinase(PD98059),p38 mitogen-activated protein kinase(SB203580),and Jun NH2-terminal kinase 1/2 inhibitor(SP600125).Interestingly,TGF-β1 significantly increased the firing threshold of action potentials but did not change their firing rate in cortical neurons.These findings suggest that TGF-β1 can increase Nav1.3 expression through activation of the ERK1/2-JNK-MAPK pathway,which leads to a decrease in the firing threshold of action potentials in cortical neurons under pathological conditions.Thus,this contributes to the occurrence and progression of neuroexcitatory-related diseases of the central nervous system. 展开更多
关键词 central nervous system cortical neurons ERK firing properties JNK Nav1.3 p38 transforming growth factor-beta 1 traumatic brain injury voltage-gated sodium currents
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Effects of Ce addition on microstructure and mechanical properties of Mg-6Zn-1Mn alloy 被引量:8
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作者 张丁非 齐福刚 +2 位作者 兰伟 石国梁 赵霞兵 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第4期703-710,共8页
The effects of Ce addition on the microstructure of Mg-6Zn-1Mn alloy during casting, homogenization, hot extrusion, T4, T6 and T4+two-step aging were investigated. The mechanical properties of alloys with and without... The effects of Ce addition on the microstructure of Mg-6Zn-1Mn alloy during casting, homogenization, hot extrusion, T4, T6 and T4+two-step aging were investigated. The mechanical properties of alloys with and without Ce were compared. The results showed that Ce had an obvious effect on the microstructure of ZM61-0.5Ce alloy by restricting the occurrence of dynamic recrystallization and restraining the grain growth during extrusion and heat treatment subsequently. A new binary phase Mg 12 Ce was identified in ZM61-0.5Ce alloy, which distributed at grain boundaries and was broken to small particles distributed at grain boundaries along extrusion direction during extrusion. The mechanical properties of as-extruded ZM61-0.5Ce alloy were improved with the addition of Ce. The improved tensile properties of as-extruded ZM61-0.5Ce alloy were due to the finer grain sizes as compared to ZM61 alloy. However, the UTS and YS decreased severely and the elongation increased when ZM61-0.5Ce was treated by T6 and T4+two-step aging. Brittle Mg 12 Ce phase, which was distributed at the grain boundary areas and cannot dissolve into the Mg matrix after solution treatment, became crack source under tensile stress. 展开更多
关键词 Mg-6Zn-1Mn alloy CERIUM MICROSTRUCTURE mechanical properties
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Microstructure,mechanical properties and creep resistance of Mg-(8%-12%)Zn-(2%-6%) Al alloys 被引量:4
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作者 万晓峰 倪红军 +2 位作者 黄明宇 张华丽 孙建华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第4期896-903,共8页
The microstructural characteristics, mechanical properties and creep resistance of Mg-(8%-12%) Zn-(2%-6%) A1 alloys were investigated to get a better overall understanding of these series alloys. The results indic... The microstructural characteristics, mechanical properties and creep resistance of Mg-(8%-12%) Zn-(2%-6%) A1 alloys were investigated to get a better overall understanding of these series alloys. The results indicate that the microstructure of the alloys ZA82, ZA102 and ZA122 with the mass ratio of Zn to A1 of 4-6 is mainly composed of a-Mg matrix and two different morphologies of precipitates (block τ-Mg32(Al, Zn)49 and dense lamellar ε-Mg51Zn20), the alloys ZA84, ZA104 and ZA124 with the mass ratio of 2-3 contain α-Mg matrix and only block r phases, and the alloys ZA86, ZA106 and ZA126 with the mass ratio of 1-2 consist of a-Mg matrix, block r precipitates, lamellar Ф-Al2Mg5Zn2 eutectics and flocculent β-Mg17Al12 compounds. The alloys studied with the mass ratio of Zn to A1 of 2-3 exhibit high creep resistance, and the alloy ZA124 with the continuous network of r precipitating along grain boundaries shows the highest creep resistance. 展开更多
关键词 Mg-Zn-A1 alloys MICROSTRUCTURE mechanical property creep resistance
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Effect of zirconium addition on microstructure and mechanical properties of Mg_(97)Y_2Zn_1 alloy 被引量:5
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作者 陈彬 卢晨 +1 位作者 林栋樑 曾小勤 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第4期773-778,共6页
The effects of zirconium addition on the microstructure and mechanical properties of Mg97Y2Zn1 alloy were investigated.The microstructure of as-cast Mg97Y2Zn1 alloy is refined by the addition of zirconium.During the e... The effects of zirconium addition on the microstructure and mechanical properties of Mg97Y2Zn1 alloy were investigated.The microstructure of as-cast Mg97Y2Zn1 alloy is refined by the addition of zirconium.During the extrusion,the initial nucleation sites of the alloy are mainly original grain boundaries and secondary phase.The addition of zirconium could stimulate the DRX process because more grain boundaries are formed,which increases the dynamic recrystallization rate.Both the strength and elongation of the alloy are increased by the addition of zirconium. 展开更多
关键词 Mg97Y2Zn1 ZIRCONIUM MICROSTRUCTURE mechanical properties
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Effect of heat treatment on microstructures and mechanical properties of sand-cast Mg-4Y-2Nd-1Gd-0.4Zr magnesium alloy 被引量:7
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作者 刘志杰 吴国华 +2 位作者 刘文才 庞松 丁文江 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第7期1540-1548,共9页
Influence of heat treatment on the microstructures and mechanical properties of sand-cast Mg-4Y-2Nd-1Gd-0.4Zr magnesium alloy was investigated,and the tensile fracture mechanisms of the studied alloys under different ... Influence of heat treatment on the microstructures and mechanical properties of sand-cast Mg-4Y-2Nd-1Gd-0.4Zr magnesium alloy was investigated,and the tensile fracture mechanisms of the studied alloys under different conditions were also discussed.The results show that the optimum T4 and T6 heat treatment conditions for the as-cast Mg-4Y-2Nd-1Gd-0.4Zr alloy are 525°C,8 h and(525°C,8 h)+(225°C,16 h),respectively,with regard to the microstructure observation,DSC heating curve and mechanical properties.The hardness,yield strength,ultimate tensile strength and elongation of the Mg-4Y-2Nd-1Gd-0.4Zr alloy treated by optimum T6 heat treatment are HV91,180 MPa,297 MPa and 7.4%,respectively.Moreover,the Mg-4Y-2Nd-1Gd-0.4Zr alloys under different heat treatment conditions exhibit different tensile fracture modes. 展开更多
关键词 Mg-4Y-2Nd-1Gd-0.4Zr alloy sand-casting heat treatment mechanical property
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Influence of pre-deformation on age-hardening response and mechanical properties of extruded Mg-6%Zn-1%Mn alloy 被引量:4
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作者 石国梁 张丁非 +3 位作者 张红菊 赵霞兵 齐福刚 张奎 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第3期586-592,共7页
The effect of cold plastic deformation between solution treatment and artificial aging on the age-hardening response and mechanical properties of alloy was investigated by micro-hardness test,tensile test,optical micr... The effect of cold plastic deformation between solution treatment and artificial aging on the age-hardening response and mechanical properties of alloy was investigated by micro-hardness test,tensile test,optical microscopy(OM) and TEM observation.After solution treatment at 420 ℃ for 1 h,three kinds of pre-deformation strains,i.e.0,5% and 10%,were applied to extruded ZM61 bars.Age-hardening curves show that pre-deformation can significantly accelerate the precipitation kinetics and increase peak-hardness value;however,as pre-deformation strain rises from 5% to 10%,there is no gain in peak hardness value.The room temperature(RT) tensile properties demonstrate that increasing the pre-deformation degree can enhance the yield strength(YS) and ultimate tensile strength(UTS) but moderately reduce elongation(EL);furthermore,the enhancement of YS is larger than that of UTS.No twin can be observed in 5% pre-deformed microstructure;however,a large number of twins are activated after 10% pre-deformation.The peak-aged TEM microstructure shows that pre-deformation can increase the number density of rod-shaped β 1 ' precipitates which play a key role in strengthening ZM61 alloy. 展开更多
关键词 Mg-6%Zn-1%Mn(ZM61 PRE-DEFORMATION age-hardening response mechanical properties
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A first-principles study on elastic properties and stability of Ti_xV_(1-x)C multiple carbide 被引量:2
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作者 王新洪 张敏 +1 位作者 阮立群 邹增大 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第6期1373-1377,共5页
The structure,stability and elastic properties of di-transition-metal carbides TixV1-xC were investigated by using the first-principles with a pseudopotential plane-waves method.The results show that the equilibrium l... The structure,stability and elastic properties of di-transition-metal carbides TixV1-xC were investigated by using the first-principles with a pseudopotential plane-waves method.The results show that the equilibrium lattice constants of TixV1-xC show a nearly linear reduction with increasing addition of V.The elastic properties of TixV1-xC are varied by doping with V.The bulk modulus of Ti0.5V0.5C is larger than that of pure TiC,as well as Ti0.5V0.5C has the largest C44 among TixV1-xC(0≤x≤1),indicating that Ti0.5V0.5C has higher hardness than pure TiC.However,Ti0.5V0.5C presents brittleness based on the analysis of ductile/brittle behavior.The Ti0.5V0.5C carbide has the lowest formation energy,indicating that Ti0.5V0.5C is more stable than all other alloys. 展开更多
关键词 elastic properties TixV1-xC carbide the first-principles phase stability
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Microstructures and mechanical properties of as-extruded and heat treated Mg-6Zn-1Mn-4Sn-1.5Nd alloy 被引量:3
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作者 胡光山 张丁非 +3 位作者 董于凤 谌夏 蒋璐瑶 潘复生 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第5期1439-1445,共7页
The microstructures and mechanical properties of Mg-6Zn-1Mn-4Sn-1.5Nd alloy subjected to extrusion and T5 treatment were investigated using optical microscopy(OM), X-ray diffractometer(XRD), scanning electron micr... The microstructures and mechanical properties of Mg-6Zn-1Mn-4Sn-1.5Nd alloy subjected to extrusion and T5 treatment were investigated using optical microscopy(OM), X-ray diffractometer(XRD), scanning electron microscopy(SEM), electron back scattered diffraction(EBSD), transmission electron microscopy(TEM), hardness tests and uniaxial tensile tests. The results showed that the as-cast alloy consisted of α(Mg), Mn, Mg7Zn3, Mg2 Sn and Mg Sn Nd phases. Dynamic recrystallization has completed during the extrusion process and the average grain size was 7.2 μm. After T5 treatment, the strength increased obviously, the yield strength and ultimate tensile strength of as-extruded alloy were increased by 94 and 34 MPa, respectively. Microstructure characterization revealed that the improvement of strength was determined by the high number density of β′1 rods. 展开更多
关键词 Mg-6Zn-1Mn-4Sn-1.5Nd alloy extrusion T5 heat treatment MICROSTRUCTURES mechanical properties
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Carbon, Nitrogen, and Chalcogen Substitution Effects on 2,1,3-Benzothiadiazole Derivative: Theoretical Investigations of Electronic, Optical, and Charge Transport Properties
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作者 胡波 姚婵 +2 位作者 王庆伟 张浩 于健康 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第1期25-30,I0003,共7页
A series of CH2, NH, O, and Se substituted 2,1,3-benzothiadiazote derivatives have been designed and investigated computationally to elucidate their potential as organic light-emitting materials for organic light-emit... A series of CH2, NH, O, and Se substituted 2,1,3-benzothiadiazote derivatives have been designed and investigated computationally to elucidate their potential as organic light-emitting materials for organic light-emitting diodes. Both ab initio Hartree-Foek and hybrid density functional methods are used. It is found that S by CH2, NH, O, and Se makes it possible transport properties of the pristine molecule adjusting the central aromatic ring by replacing to fine-tune the electronic, optical, and charge 展开更多
关键词 Organic light-emitting diode 2 1 3-benzothiadiazole Electronic property Optical property Reorganization energy
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Density Functional Theory Study on Electronic and Magnetic Properties of Mn-doped (MgO)n (n=2-10) Clusters
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作者 王鹏 杨明霞 +2 位作者 张胜利 黄世萍 田辉平 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第1期35-42,I0003,共9页
We study the geometries, stabilities, electronic and magnetic properties of (MgO)n (n=2-10) clusters doped with a single Mn atom using the density functional theory with the gener- alized gradient approximation. T... We study the geometries, stabilities, electronic and magnetic properties of (MgO)n (n=2-10) clusters doped with a single Mn atom using the density functional theory with the gener- alized gradient approximation. The optimized geometries show that the impurity Mn atom prefers to replace the Mg atom which has low coordination number in all the lowest-energy MnMgn-1On (n=2-10) structures. The stability analysis clearly represents that the average binding energies of the doped clusters are larger than those of the corresponding pure (MgO)n clusters. Maximum peaks of the second order energy differences are observed for MnMg~_1On clusters at n=6, 9, implying that these clusters exhibit higher stability than their neighboring clusters. In addition, all the Mn-doped Mg clusters exhibit high total magnetic moments with the exception of MnMgO2 which has 3.00μB. Their magnetic behavior is attributed to the impurity Mn atom, the charge transfer modes, and the size of MnMgn- 1On clusters. 展开更多
关键词 Density functional theory MnMgn-1On cluster Electronic property MAGNETICproperty
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Influence of Al Composition on Transport Properties of Two-Dimensional Electron Gas in Al_xGa_(1-x)N/GaN Heterostructures
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作者 唐宁 沈波 +7 位作者 王茂俊 杨志坚 徐科 张国义 桂永胜 朱博 郭少令 褚君浩 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第2期235-238,共4页
Magnetotransport properties of two-dimensional electron gases (2DEG) in AlxGa1-x N/GaN heterostructures with different Al compositions are investigated by magnetotransport measurements at low temperatures and in hig... Magnetotransport properties of two-dimensional electron gases (2DEG) in AlxGa1-x N/GaN heterostructures with different Al compositions are investigated by magnetotransport measurements at low temperatures and in high magnetic fields. It is found that heterostructures with a lower Al composition in the barrier have lower 2DEG concentration and higher 2DEG mobility. 展开更多
关键词 Alx Ga1-x N/GaN heterostructure two-dimensional electron gas transport property
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BFe10-1-1摩擦塞补焊接头组织及性能研究 被引量:1
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作者 张忠科 陈荣耀 纪宝成 《有色金属工程》 CAS 北大核心 2024年第6期1-8,共8页
采用顶锻式摩擦塞补焊方法对5 mm厚的BFe10-1-1铜镍合金进行匙孔补焊实验,探讨了不同主轴转速下塞补焊接头的微观形貌、显微硬度、温度场分布及其力学性能。结果表明:主轴转速对铁白铜塞补焊成形有重要的影响,随着转速提高,接头底部缺... 采用顶锻式摩擦塞补焊方法对5 mm厚的BFe10-1-1铜镍合金进行匙孔补焊实验,探讨了不同主轴转速下塞补焊接头的微观形貌、显微硬度、温度场分布及其力学性能。结果表明:主轴转速对铁白铜塞补焊成形有重要的影响,随着转速提高,接头底部缺陷逐渐缩小,塞棒区金属摩擦流线明显,晶粒呈破碎细化特征,接头从上到下,热影响区范围缩小明显。由于细晶强化作用,塞棒区显微硬度高于母材,且塞棒上侧显微硬度高于中下侧。在转速为2 100 r/min时得到接头拉伸强度最高,达到母材78%。接头表现出韧性断裂特征,随着转速提高,接头弱连接缺陷逐步下移,并不断缩小。 展开更多
关键词 BFE10-1-1 摩擦塞补焊 显微组织 力学性能 主轴转速
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微波烧结对(Mg_(0.9)Zn_(0.1))TiO_(3)-(Ca_(0.61)La_(0.26))TiO_(3)陶瓷性能的影响
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作者 赵莉 胡玉叶 +2 位作者 潘福婷 温学涛 蒋亚龙 《材料科学与工程学报》 CAS CSCD 北大核心 2024年第4期647-650,共4页
通过微波烧结和常规烧结法成功制备(1-x)(Mg_(0.9)Zn_(0.1))TiO_(3)-x(Ca_(0.61)La_(0.26))TiO_(3)(x=0.15,简称85M_(9)Z_(1)CLT)陶瓷。实验结果表明,微波烧结大大缩短了85M_(9)Z_(1)CLT陶瓷的烧结周期,抑制了杂质相(Mg_(0.9)Zn_(0.1))T... 通过微波烧结和常规烧结法成功制备(1-x)(Mg_(0.9)Zn_(0.1))TiO_(3)-x(Ca_(0.61)La_(0.26))TiO_(3)(x=0.15,简称85M_(9)Z_(1)CLT)陶瓷。实验结果表明,微波烧结大大缩短了85M_(9)Z_(1)CLT陶瓷的烧结周期,抑制了杂质相(Mg_(0.9)Zn_(0.1))Ti_(2)O_(5)的生成;微波烧结制备的85M_(9)Z_(1)CLT陶瓷表现出Zn蒸发量少、晶粒更均匀、颗粒更细小的微观结构。与传统烧结相比,微波烧结的85M_(9)Z_(1)CLT陶瓷的品质因数提高了21%。在1325℃下微波烧结20min升降温速率为15℃/min时,85M_(9)Z_(1)CLT微波介电陶瓷的性能最佳:ε_(r)=25.63,Q·f=116000GHz,τ_(f)=+1×10^(-6)/℃。 展开更多
关键词 85M_(9)Z_(1)CLT 微波烧结 介质陶瓷 介电性能
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Preparation and Electrochemical Properties of 3-Pyridinyl-6-aryl-1,2,4-triazolo [3,4-b][1, 3,4]thiadiazoles 被引量:3
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作者 TaiXIAO HuiXueLI +1 位作者 ChunXiaTAN MiaoCHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第3期335-337,共3页
A series of 3-pyridinyl-6-aryl-l, 2, 4-triazolo[3, 4-b][1, 3, 4]thiadiazoles(PATT) were prepared, the structures were confirmed by IR and H NMR spectra. The results of cyclic 1 voltammetry measurements imply that all ... A series of 3-pyridinyl-6-aryl-l, 2, 4-triazolo[3, 4-b][1, 3, 4]thiadiazoles(PATT) were prepared, the structures were confirmed by IR and H NMR spectra. The results of cyclic 1 voltammetry measurements imply that all these compounds have a higher electron affinity (EA) than 2-(4-biphenyl)-5-(4-tert-butyl phenyl)-1, 3, 4-oxadiazole (PBD) which implies that PATT could be acting as better electron acceptors than widely used electron transporting material PBD. 展开更多
关键词 PREPARATION 3-pyridinyl-6-aryl-1 2 4-triazolo[3 4-b][1. 3 4]thiadiazoles electro- chemical properties.
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Effect of Trace La Addition on the Microstructure and Mechanical Property of As-cast ADC12 Al-Alloy 被引量:25
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作者 黄昕 闫洪 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2013年第1期202-205,共4页
The effects of addition of La on the microstructure of as-cast ADC12 A1-Alloy were investigated by using optical microscope (OM), X-ray diffraction (XRD), scanning electron microscope (SEM), and energy disperse ... The effects of addition of La on the microstructure of as-cast ADC12 A1-Alloy were investigated by using optical microscope (OM), X-ray diffraction (XRD), scanning electron microscope (SEM), and energy disperse spectroscopy (EDS). The experimental results showed that the a-A1 and eutectic Si crystals were modified with the addition of 0.3 wt% La. The eutectic Si crystals showed a granular distribution. At the same time, the alloy possessed the best mechanical property. When more than 0.3 wt% La was added to ADC12 aluminum alloy, the microstructure of as-cast alloy was coarsening gradually with the increase of the content of La and the mechanical property decreased. The effect of rare earth La which was added in ADC 12 A1-Alloy for up to 0.9 wt% had been investigated in this study. The dendrites ofADC12 Al-alloy was refined obviously and the morphology of Si crystals showed a particle structure when the addition of La reached 0,3 wt%. Besides, the acicular La-rich intermetallics in the alloy deteriorated the mechanical property of alloy: To avoid this unwanted phase, the amount of added rare earth La must be less than 0.6 wt%. 展开更多
关键词 as-cast ADC12 A1-Alloy rare earth microstructure intermetallic compound mechanical property
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Effects of cooling rate on bio-corrosion resistance and mechanical properties of Mg-1Zn-0.5Ca casting alloy
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作者 王立东 李雪松 +2 位作者 王超 王立民 曹占义 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第3期704-711,共8页
Mg?1Zn?0.5Ca alloys were prepared by traditional steel mould casting and water-cooled copper mould injection casting at higher cooling rate. Microstructure, mechanical properties and bio-corrosion resistance of two al... Mg?1Zn?0.5Ca alloys were prepared by traditional steel mould casting and water-cooled copper mould injection casting at higher cooling rate. Microstructure, mechanical properties and bio-corrosion resistance of two alloys were contrastively investigated. Grain size reduces remarkably and microstructure becomes homogenous when raising cooling rate. The bio-corrosion behaviour in 3.5% sodium chloride solution (3.5% NaCl) and Hank’s solution at 37°C was investigated using electrochemical polarization measurement and the results indicate that the alloy prepared at higher cooling rates has better corrosion resistance in both types of solution. Further mass loss immersion test in Hank’s solution reveals the same result. The reason of corrosion resistance improvement is that raising cooling rate brings about homogeneous microstructure, which leads to micro-galvanic corrosion alleviation. The tensile test results show that yield strength, ultimate tensile strength and elongation are improved by raising cooling rate and the improvement is mainly due to grain refinement. 展开更多
关键词 Mg-1Zn-0.5Ca alloy cooling rate bio-corrosion resistance micro-galvanic corrosion mechanical properties
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Effect of heat treatment on microstucture and properties of explosive welding clad plate of TA1/Q345 被引量:11
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作者 Zhang Min Zhang Tao +2 位作者 Cai Junqing Liu Juanjuan Li Jihong 《China Welding》 EI CAS 2018年第1期26-31,共6页
The composite plate made by explosion welding technology generally has high residual stress and bed plasticity due to the explosion reinforcement. The heat treatment can play a part of eliminating stress and recoverin... The composite plate made by explosion welding technology generally has high residual stress and bed plasticity due to the explosion reinforcement. The heat treatment can play a part of eliminating stress and recovering property.In this study,TA1/Q345 clad plate made by explosive welding was annealed at different temperatures.The microstructure,micro-hardness,and tensile,shear,and bending properties were analyzed after anneal.The result shows that there is fibrous structure in the bonding zone and the plastic deformation is severe,the grain growth and fibrous structure dribbles away with the temperature increasing.Micro-hardness in the interface is bigger than it on the both sides. Tensile and shear strength reduced with the temperature of heat treatment increasing.The propel anneal temperature for TA1/Q345 clad plate is 600 展开更多
关键词 METALLIC material TA1/Q345 CLAD PLATE heat treatment microstructure mechanical properties
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Effects of Li addition on the microstructure and tensile properties of the extruded Mg-1Zn-xLi alloy 被引量:3
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作者 Jun Zhao Bin Jiang +4 位作者 Qinghang Wang Ming Yuan Yanfu Chai Guangsheng Huang Fusheng Pan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第7期1380-1387,共8页
Li addition is verified to be an effective method to increase the room temperature ductility and formability of Mg alloys.In the present study,the microstructure,texture,and tensile properties of the extruded Mg-1Zn-x... Li addition is verified to be an effective method to increase the room temperature ductility and formability of Mg alloys.In the present study,the microstructure,texture,and tensile properties of the extruded Mg-1Zn-xLi(wt%,x=0,1,3,5)alloy sheets were studied by X-ray diffraction(XRD),scanning electron microscope(SEM),and electron backscatter diffraction(EBSD).It was found that Li addition resulted in the grain coarsening and the development of new transverse direction(TD)-tilting and{101^(-)0}parallel to extrusion direction textures,which was related to the improved dynamic recrystallization and the increased prismatic slip during extrusion.The Mg-1 Zn-5 Li sheet showed the weakest texture,which contained both basal and TD-tilting oriented grains.No additional phase was formed with Li addition.The yield strength of Mg-1Zn-xLi sheets gradually decreased with increasing Li content,which was mainly related to the grain coarsening and texture weakening.In addition,the ductility of the Mg-1Zn-xLi sheet was remarkably enhanced by Li addition.The elongation of the Mg-1 Zn-5 Li sheet was 30.3%along the TD,which was three times than that of Mg-1 Zn sheet.Microstructural analysis implied that this significant ductility enhancement was associated with the improvement activation of prismatic and basal slips during the tensile tests.This study may provide insights into the development of high-ductility,low-density Mg-Zn-Li based alloys. 展开更多
关键词 Mg-1Zn-xLi alloy texture prismatic slip tensile properties
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Electronic structure and optical properties of Mg_xZn_(1-x)S bulk crystal using first-principles calculations 被引量:2
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作者 余志强 徐智谋 武兴会 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第10期441-446,共6页
We perform the first-principles calculations within the framework of density functional theory to determine the elec- tronic structure and optical properties of MgxZnl-xS bulk crystal. The results indicate that the el... We perform the first-principles calculations within the framework of density functional theory to determine the elec- tronic structure and optical properties of MgxZnl-xS bulk crystal. The results indicate that the electronic structure and optical properties of MgxZnl_xS bulk crystal are sensitive to the Mg impurity composition. In particular, the MgxZnl-xS bulk crystal displays a direct band structure and the band gap increases from 2.05 eV to 2.91 eV with Mg dopant compo- sition value x increasing from 0 to 0.024. The S 3p electrons dominate the top of valence band, while the Zn 4s electrons and Zn 3p electrons occupy the bottom of conduction band in MgxZnl_xS bulk crystal. Moreover, the dielectric constant decreases and the optical absorption peak obviously has a blue shift. The calculated results provide important theoretical guidance for the applications of MgxZn1-xS bulk crystal in optical detectors. 展开更多
关键词 FIRST-PRINCIPLES MgxZn1-xS electronic structure optical properties
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