检索结果-南通市图书馆

Journal of Materials Science & Technology 2022年第1期96卷 85-93页

作者： q.Yan B.Chen l.Cao k.Y.liu S.li l.Jia k.kondoh J.S.li State key laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048China Joining and Welding Research Institution Osaka University11-1 MihogaokaIbarakiOsaka 567-0047Japan

In order to construct quasi-continuously networked reinforcement in titanium(Ti)matrix composites,in this study,Ti-6 Al-4 V spherical powders were uniformly coated with a graphene nanosheet(GNS)layer by high energy ball milling and then consolidated by spark plasma *** showed that the GNS layer on the powder surface inhibited continuous metallurgy bonding between powders during sintering,which led to the formation of quasi-networked hybrid reinforcement structure consisting of insitu Ti C and remained *** networked GNSs/Ti64 composite possessed noticeably higher tensile strength but similar ductility to the Ti64 alloy,leading to both better tensile strength and ductility than the GNSs/Ti composite with randomly dispersed GNSs and Ti *** formation mechanism and the fracture mechanism of the networked hybrid reinforcement were *** results provided a method to fabricate Ti matrix composites with high strength and good ductility.

关键词： Titanium matrix composites(TMCs) Graphene Network structure Strength Ductility

INVESTIGATION OF WO3-DOPED TiO2 FIlM COMPOSITE PHOTOCATAlYST

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English letters) 2004年第3期17卷 263-268页

作者： q.F. Meng k.R. liu l. Jiang q. Han J.S. Chen X.J. Wei School of Materials & Metallurgy Northeastern University Shenyang 110004 ChinaSchool of Materials & MetallurgyNortheastern University Shenyang 110004 ChinaSchool of Materials & MetallurgyNortheastern University Shenyang 110004 ChinaSchool of Materials & MetallurgyNortheastern University Shenyang 110004 ChinaSchool of Materials & MetallurgyNortheastern University Shenyang 110004 ChinaSchool of Materials & MetallurgyNortheastern University Shenyang 110004 China

The nano--crystal composite WO_3-TiO_2 photocatalyst was prepared by ultrasonic as-sisted sol--gel process. The effects of various factors, such as the crystal form, thesubstrates, the pH, the dissolved oxygen and the ultrasonic on the photocatalytic ac-tivity were investigated in view of the photodegradation of Rhodamine B. The resultsshow that the crystal form of WO_3-TiO_2 film with highest photocatalytic activity isrutile. The introduction of ultrasonic to the course of preparation can accelerate thedeposit time of the sol and increase the photocatalytic activity significantly in view ofthe highest photodegradation of Rhodamine B being 72.7% in 5 hours. The poroustitanium plate is the most suitable substrate in four kinds of investigated materials.Meanwhile the smaller the pH and the higher the concentration of the dissolved oxygenin the solution is, the higher the photodegradation is.

关键词： ultrasonic sol-gel process photocatalytic photodegradation

Influence of Fe Addition on Products of Self-Propagating High-Temperature Synthesis Reaction in 3Ti-Si-2C System

在线全文

学校读者我要写书评

暂无评论

稀有金属材料与工程 2009年第A3期38卷 113-118页

作者： Guan q l Wang H Y li S l Si W P Jiang q C key laboratory of Automobile Materials of Ministry of Education Jilin University Changchun 130025 China

Influence of Fe addition on products of self-propagating high-temperature synthesis (SHS) reaction in 3Ti-Si-2C system was investigated in the present study. Without Fe addition, Ti5Si3 and TiC are the dominant phases along with a small amount of Ti3SiC2 phase and unreacted C left in the final products. As Fe content ranges from 10% to 30%, the products consist of TiC, Ti5Si3, Fe2Ti and unreacted C, but no trace of Ti3SiC2 phase is detected. Furthermore, the amounts of both Fe2Ti and C phases increase with Fe content increasing. Addition of Fe has a great effect on the reaction route and significantly restrains the formation of Ti3SiC2 during the combustion synthesis process, and therefore, the SHS is not an effective fabrication technique to synthesize the ternary Ti3SiC2 ceramic in either 3Ti-Si-2C or Fe-3Ti-Si-2C system. Besides, without Fe addition, Ti5Si3 presents as the coarse irregular appearance with an obviously sintered morphology. In contrast, the shape of Ti5Si3 exhibits more and more spherical (cobblestone-like) and the surface becomes increasingly smooth, because the amount of liquids formed during the SHS reaction increases with the increase of Fe content. On the other hand, with Fe content increasing from 0 to 30 wt.%, the particulate size of TiC decreases from more than 5 μm to 1 μm or less, mainly due to the fact that the combustion temperature decreases with the increase of Fe content in the preforms.

关键词：复合材料铁含量燃烧过程物理性能

Influence of high configuration entropy on damping behaviors of Ti-Zr-Hf-Ni-Co-Cu high entropy alloys

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2023年第22期153卷 242-253页

作者： W.q.Wu l.Zhang k.k.Song J.M.Pelletier H.F.Zhang J.C.qiao School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an 710072China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Mechanical and Electrical Engineering Shandong UniversityWeihai 264209China universitéde lyon MATEISUMR CNRS5510Bat.B.PascalINSA-LyonVilleurbanne Cedex F-69621France Chongqing Science and Technology Innovation Center of NPu Chongqing 401135China

TiNi-based shape memory alloys(SMAs)have been used as damping materials to eliminate noise and mechanical ***,their application is limited by low working temperatures and damping *** this work,two novel Ti-Zr-Hf-Ni-Co-Cu high entropy shape memory alloys(HESMAs)with different transformation temperatures and damping properties were *** results show that Ti_(25)Zr_(8)Hf_(17)Ni_(30)Co_(5)Cu_(15) has superior damping performance arising from martensitic transformation,shape memory effect(thermal cycle at constant load)as well as *** to traditional TiNi-based SMAs,the as-cast HESMAs exhibit a much higher ultrahigh yield strength(∼2 GPa)and storage modulus(∼50 GPa).The high configuration entropy of the HESMAs with high uneven internal stress and severe lattice distortion is revealed as the underlying mechanisms governing distinctive damping *** effects of high configuration entropy and microheterogeneity on the martensitic transforma-tion behavior and damping performance of HESMAs are clarified in this work,which provides a basis for designing alloys with superior damping properties.

关键词： High entropy s hape memory alloy Internal friction Damping Configuration entropy Martensitic transformation

Radiation Spectral Analysis of 3D Dust Molecular Clusters(PAHs)and Peptoids under Ionization and Electric Field in ISM

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

Research in Astronomy and Astrophysics 2024年第1期24卷 70-77页

作者： Ruiqing Wu Chunhua Zhu Guoliang lü Xiaojiao Zhang Xizhen lu Jinlong Yu Wujin Chen Mengqiu long School of Physics and Electronics Central South UniversityChangsha 410083China School of Physical Science and Technology Xinjiang UniversityUrumqi 830046China School of Microelectronics and Physics Hunan University of Technology and BusinessChangsha 410205China College of Mechanical and Electronic Engineering Tarim UniversityAlar 843300China School of Medicine Xinjiang Medical UniversityUrumqi 830011China

Polycyclic aromatic hydrocarbons(PAHs),PANHs,and peptoids dust spectral calculations from the interstellar medium(ISM)are important for dust observations and *** goal is to calculate the radiation spectrum of spherical PAHs dust clusters in a vacuum containing ionized and applied in the presence of an electric *** propose a new simple computational model to calculate the size of three-dimensional spherical dust clusters formed by different initial dust *** the Vienna Ab-initio Simulation Package code,the density functional theory with the generalized approximation was used to calculate the electron density gradient and obtain the radiation spectrum of *** the radius of spherical dust clusters is~[0.009-0.042]μm,the dust radiation spectrum agrees well with the Z=0.02 mMMP stellar spectra,and the PAHs radiation spectrum of NGC 4676 at wavelengths of(0-5]μm and(5-10]μm,*** the ionized state,the N-PAH,C_(10)H_(9)N,2(C_(4)H_(4))^(1+),and peptoids 4(CHON),(C_(8)H_(10)N_(2)O_(5))^(1+)dust clusters at 3.3μm,while the 2(C_(22)H_(21)N_(3)O_(2))^(1+),4(CHON)dust clusters at 5.2μm have obvious *** is a characteristic of part of PAHs and peptoids clusters radiation at the nearinfrared wavelength of 2μ***,especially after applying an electric field to the dust,the emission spectrum of the dust increases significantly in the radiation wavelength range[3-10]μ***,the dust clusters of PAHs,PANHs,and peptoids of the radius size~[0.009-0.042]μm are likely to exist in the ISM.

关键词： ISM:structure ISM:molecules radiation mechanisms:general (ISM:)dust extinction

联合InSAR和GNSS构建青藏高原千米分辨率三维地壳形变场

在线全文

学校读者我要写书评

暂无评论

中国科学：地球科学 2024年第6期54卷 1845-1862页

作者：刘传金季灵运朱良玉许才军赵超英 Zhong lu 王庆良武汉大学测绘学院武汉430079 中国地震局第二监测中心西安710054 长安大学地质工程与测绘学院西安710054 Roy M.Huffington Department of Earth Sciences Southern Methodist UniversityDallasTX 75025USA

青藏高原位于印度板块与欧亚板块碰撞的前沿地带,地壳运动十分活跃.受高海拔、高寒气候等因素的限制,以地面观测站为代表的传统大地测量监测较为困难,因此至今青藏高原的高空间分辨率地壳形变场尚未精确测定. InSAR技术不受地面观测条... 详细信息

青藏高原位于印度板块与欧亚板块碰撞的前沿地带,地壳运动十分活跃.受高海拔、高寒气候等因素的限制,以地面观测站为代表的传统大地测量监测较为困难,因此至今青藏高原的高空间分辨率地壳形变场尚未精确测定. InSAR技术不受地面观测条件限制,能够获得大范围、高空间分辨率的地壳形变场,在青藏高原地壳形变监测领域具有不可替代的优势.本文利用2014~2020年的Sentinel-1卫星SAR数据,计算了青藏高原升降轨InSAR形变场,测量精度约为3mm/a.在此基础上,融合InSAR与GNSS数据,获取了覆盖青藏高原的千米分辨率三维地壳形变场和应变率场.通过球面小波多尺度分析,将三维形变场分解出不同波长的形变,其中波长小于110km的形变主要来自断层运动、震后形变和其他非构造形变,大于110km的形变主要来自大范围的构造运动.研究结果显示,高原中部地区呈现大范围下沉,而喜马拉雅弧地区则呈现明显隆升,这表明青藏高原可能已经停止了整体隆升并进入了局部坍塌阶段.此外,不同空间尺度的三维形变场表明,青藏高原在短波长变形中表现为非连续形变,在长波长中则表现为连续形变.本文研究结果有助于调节青藏高原块体变形模型和连续变形模型之间的争议.

关键词：青藏高原 InSAR GNSS 三维形变形变模型

NuMERICAl SIMulATION OF CEllulAR/DENDRITIC PRIMARY SPACING

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English letters) 2004年第5期17卷 761-766页

作者： W.q,Zhang l.Xiao DepartmentofMaterialsScienceandEngineering LiaoningTechnicalUniversityFuxin123000China

A numerical model has been established to calculate the primary spacing of cellular or dendritic structure with fluid flow considered. The computing results show that the primary spacing depends on the growing velocity, the temperature gradient on the interface and fluid flow. There is a critical growing velocity for the cell-dendrite transition, which has a relationship with the temperature gradient: Rcr = (3-4)×10-9GT. Fluid flow leads to an increase of the primary spacing for dendritic growth but a decrease for cellular growth, resulting in an instability on the interface.

关键词： primary spacing model fluid flow l/S interface

Effect of Organic Manure and Chemical Amendments on Soil Properties and Crop Yield on a Salt Affected Entisol

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2005年第1期15卷 46-51页

作者： A.u.BHATTI q.kHAN A.H.GuRMANI M.J.kHAN DepartmentofSoilandEnvironmentalSciences NWFPAgriculturalUniversityPeshawarPakistan AridZoneResearchInstitute DeralsmailKhanNWFPPakistan

A field experiment was conducted for two consecutive years in a farmer's field at Haji Mora Village, Dera Ismail khan (D.I. khan) in the Northwest Frontier Province (NWPP) of Pakistan to compare various management practices, such as the effect of various organic manures and gypsum in a rice-wheat cropping system on a saline-sodic Entisol (Zindani soil series). The treatments consisted of 1) a control (rice-wheat), 2) gypsum, 3) farmyard manure (FYM), 4) berseem (Trifolium alexzndrinum l.) as green manure (GM), and 5) dhancha (Sesbania sp.) as GM. All treatments increased yields of both rice and wheat significantly (P l, with the green manure treatments proving more economical than the others; while they decreased pH, electrical conductivity (EC), and sodium adsorption ratio (SAR) of the soil. Saturation percentage and available water of the soil were raised for all treatments due to an increase in organic matter content of the soil.

关键词： berseem dhancha farm yard manure gypsum saline-sodic Entisol

Pumping-induced Well Hydraulics and Groundwater Budget in a leaky Aquifer System with Vertical Heterogeneity in Aquitard Hydraulic Properties

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2024年第2期98卷 477-490页

作者： ZHuANG Chao lÜChenyang YAN long lI Yabing ZHOu Zhifang WANG Jinguo DOu Zhi Walter A.IllMAN School of Earth Sciences and Engineering Hohai UniversityNanjing 211100China School of Geography Earth and Environmental SciencesUniversity of BirminghamBirmingham B152TTU.K. Department of Modern Mechanics University of Science and Technology of ChinaHefei 230027China Department of Earth and Environmental Sciences University of WaterlooOntario N2L 3G1Canada

In groundwater hydrology,aquitard heterogeneity is often less considered compared to aquifers,despite its significant impact on groundwater hydraulics and groundwater resources evaluation.A semi-analytical solution is derived for pumping-induced well hydraulics and groundwater budget with consideration of vertical heterogeneity in aquitard hydraulic conductivity(k)and specific storage(S_(s)).The proposed new solution is innovative in its partitioning of the aquitard into multiple homogeneous sub-layers to enable consideration of various forms of vertically heterogeneous k or S_(s).Two scenarios of analytical investigations are explored:one is the presence of aquitard interlayers with distinct k or S_(s) values,a common field-scale occurrence;another is an exponentially depth-decaying aquitard S_(s),a regional-scale phenomenon supported by statistical *** investigations reveal that a low-k interlayer can significantly increase aquifer drawdown and enhance aquifer/aquitard depletion;a high-S_(s) interlayer can noticeably reduce aquifer drawdown and increase aquitard *** of low-k or high-S_(s) interlayers also significantly impact well hydraulics and groundwater *** the context of an exponentially depth-decaying aquitard S_(s),a larger decay exponent can enhance aquifer *** using current models with a vertically homogeneous aquitard,half the sum of the geometric and harmonic means of exponentially depth-decaying aquitard S_(s) should be used to calculate aquitard depletion and unconfined aquifer leakage.

关键词： hydrogeology aquitard vertical heterogeneity semi-analytical solution well hydraulics groundwater budget

Reduction effect of final-pass heavy reduction rolling on the texture development,tensile property and stretch formability of ZWk100 alloy plates

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2022年第16期111卷 211-223页

作者： B.q.Shi l.Y.Zhao X.l.Shang B.H.Nie D.C.Chen C.q.li Y.q.Cheng School of Materials Science and Hydrogen Energy Foshan UniversityFoshan 528000China School of Materials and Energy Guangdong University of TechnologyGuangzhouGuangdong 510006China GD Midea Air-Conditioning Equipment Co. Ltd.Foshan 528311China Guangdong key laboratory of Hydrogen Energy Technology Foshan 528000China YunFu(Foshan)R&D Center of Hydrogen Energy Standardization Yunfu 527326China

Obviously planar anisotropy due to‘TD split’orthotropic texture(TD indicates Transverse direction)always exist in the Rare-earth(RE)or Ca containing Mg alloy sheets,which is likely caused by the lowreduction rolling(and annealing)as revealed in our previous *** this work,the as-cast billets of a ZWk100 alloy were subjected to final-pass heavy reduction rolling(FHRR)at 500°C with different reductions(30%-70%)after rough rolling,aiming to investigate the reduction effect on the microstructure and texture *** results show that FHRR with higher reductions above 50%is in favor of shear banding formation but has little effect on the as-deformed texture components,and the excellent formability with single-pass reduction up to 70%is mainly ascribed to the activation of prismatic *** with reduction above 50%and annealing can generate uniform grain structures of~10μm and symmetrical‘oblique-line split’texture in(0001)pole figures,with basal poles tilting by about 50°from ND(Normal direction)towards some oblique-line of TD and RD(Rolling direction)as well as uniform distribution of counter lines as an annular shape,resulting in excellent elongation to failure of~50%and ultra-low planar anisotropyΔr_of~0.1 and high stretch formability(Erichsen value:8.1).The formation‘oblique-line split’texture in(0001)pole figures is mainly correlated with the preferred growth tendency of grains with■//RD,which was suggested to relate to the high mobility of some special boundaries such as 40°-45°■.The influences of starting textures on the mechanical properties,planar anisotropy and related deformation modes,as well as their correlations with the stretch formability were comparatively investigated with the‘TD split’orthotropic texture as a counterpoint.

关键词： Magnesium alloys Texture Plane anisotropy Stretch formability Rolled sheets