检索结果-南通市图书馆

Relationship between Ballistic Coefficient and Static Mechanical Properties for Armor materials

在线全文

学校读者我要写书评

暂无评论

Journal of university of science and technology beijing 2001年第1期8卷 53-54页

作者： junpin lin, Yong Zhang, zhi lin, guoliang Chen The State key laboratory for advanced metal materials, university of science and technology beijing, beijing 100083, china State key Lab. advanced metal Mat. Univ. of Sci. and Technology Beijing Beijing 100083 China

The relationship between the ballistic coefficient and the static mechanical properties of armor materials was studied. The results show that the ballistic coefficient is determined by the strength, hardness and the toughness of materials. According to the Martel rule, the equation of the relationship between ballistic coefficient and static mechanical properties satisfies the following formula: W-s=M(1+NK1C/rho )Hr. From the mixture law of composite, the prerequisite, for which ballistic coefficient has maximum to reinforcement volume fraction, is obtained by the following equation: dWs/Df=b(K(1)rho (0)-K(0)rho (1))H/rho (2)+(a+bK/rho)(H-1-H-0).

关键词： armor materials ballistic coefficient toughness

Mechanism of High Temperature Deformation in Cast Ti46Al8.5Nb0.2W Alloy

在线全文

学校读者我要写书评

暂无评论

Journal of university of science and technology beijing 2001年第4期8卷 290-294页

作者： Zicheng Liu, junpin lin, yanli wang, zhi lin, guoliang Chen State key laboratory for advanced metals and materials, university of science and technology beijing, beijing 100083, china State key laboratory for advanced metals and materials University of Science and Technology Beijing Beijing 100083 China

Compression tests A ere conducted in the two phase Ti46Al8.5Nb0.2W alloy with a cast microstructure under the strain rates ranging from 2x10(-5) s(-1) to 10(-2) s(-1) at temperatures ranging front 900degreesC to 1100degreesC. It was found that there exist approximately linear relationships between the flow stress and the logarithm of strain rate at different temperatures. The strain rate dependence was analzed by the thermal activation theory and dislocation climbing is regarded as the controlling mechanism during high temperature compression tests.

关键词： Ti46%Al8.5%Nb0.2%W high temperature compression strain rate dislocation climbing

Homogenization treatment of high Nb containing TiAl alloys with as-cast and as-forged microstructures

在线全文

学校读者我要写书评

暂无评论

Rare metals 2008年第2期27卷 181-186页

作者： XU Zhengfang XU Xiangjun lin junpin ZHANG Yong wang yanli lin zhi CHEN guoliang State key laboratory for advanced metals and materials University of Science and Technology Beijing Beijing 100083 China

The effect of heat treatment on the microstructure evolution of a high Nb containing TiAl alloy has been studied. The results indicate that β-segregation, β-segregation and S-segregation in the as-cast and as-forged alloys can be effectively eliminated at the temperature above Tα （1350-1400℃） for long holding time （12-24 h） and the full lamellar （FL） microstructure is gained. For the two alloys, the lamellar colony sizes are 120 μm and 2000 μm, respectively after heat treatment at 1400℃ for 12 h. Meanwhile, the sizes are 210 μm and 3000 μm, respectively at 1350℃ for 24 h. To get a fine homogenous microstructure, the primary as-cast alloy is first subjected to preheat treatment for eliminating the segregations. After the preheat treatment, the ailoy is processed by the multi-step canned forging to attain the microstructure with fine grain size.

关键词： TiAl-based alloy Nb-containing FL microstructure heat treatment rnicrosegregation

Deformation-induced α_2/γ Interfaces in a Hot-deformed Ti-45Al-10Nb Alloy

在线全文

学校读者我要写书评

暂无评论

Journal of materials science & technology 1998年第2期14卷 132-138页

作者： Jinguo wang Lichun ZHANG and guoliang CHEN (State key Lab. for advanced metals and materials, university of science and technology beijing, beijing 100083, china )Henqiang YE(Lab. of Atomic Imaging of Solids, Institute of metal Research, Chinese Academy State key Lab. for advanced metals and materials University of Science and Technology Beijing Beijing 100083 China Lab. of Atomic Imaging of Solids Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

The structure change of α2/γ interface in a Ti-45Al-10Nb alloy induced by hot deformation was investigated by conventional and high-resolution transmission eIectron microscopy. Two types of hot deformation induced special α2/γ intedeces, coherent intedeces with high density of ledges and semi-coherent α2/γ intedeces were found to be due to the absorption of mobile dislocations into the α2/γ inteface. For the misoriented semi-coherent α2/γ interfaces, the densities of dislocation ledges increase with the misoriented angle between (111)γ and (0001)α2 planes, and 1/3[111] Frank partial dislocations were involved in the dislocation ledges. Formation mechanism of these deformation-induced α2/γ interfaces was discussed to be related to the role of α2/γ interface5 adjusting the deformation as a dislocation sink absorbing the slipping dislocations in the γ phase

关键词： Al Ti Interfaces in a Hot-deformed Ti-45Al-10Nb Alloy Deformation-induced

Suppression of the regrowth interface leakage current in AlGaN/GaN HEMTs by Fe doped GaN substrate

在线全文

学校读者我要写书评

暂无评论

science china(Information sciences) 2024年第6期67卷 461-462页

作者： Xiao wang zhi-Yu lin Yuan-Hang SUN Long YUE Yu-Min ZHANG Jian-Feng wang Ke XU School of Nano-Tech and Nano-Bionics University of Science and Technology of China Suzhou Institute of Nano-tech and Nano-bionics Chinese Academy of Sciences Information materials Research Department Suzhou laboratory Suzhou Nanowin science and technology Co. Ltd. Jiangsu Institute of advanced Semiconductors

In the process of homoepitaxy AlGaN/GaN heterojunction by metal-organic chemical vapor deposition (MOCVD) on free-standing substrates,Si impurities from the air and reaction chamber accumulate at the regrowth interfac...

关键词：

Phase Relations in TiAl+Nb System

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of materials science & technology 1994年第5期10卷 359-366页

作者： Jingguo wang guoliang CHEN and Zuqing SUN (State key Lab. for advanced metal materials, university of science and technology beijing, beijing, 100083, china)Hengqiang YE (Lab. of Atomic Imaging of Solids, Institute of metal Research, Academia Sinica, Sh Univ of science and technology Beijing China

The microstructures and phases of ternary TiAl+Nb alloys containing 50-60 at.-%Al, 0-21 at.-%Nb have been studied using transmission electron microscopy (TEM) and X-ray powder diffraction. The phases present in the alloys and their distribution were found to be a sensitive function of composition. The phase relations between γ-TiAl and γ1 (a new ordered ternary intermetallic compound based on γ-TiAl) were determined. Essentially single γ phase was determined for alloys with relativety low Nb content (≤10 at.-%Nb). the γ1 phase was determined to exist in the composition range containing higher Nb contents (15-21 at.-%Nb). Between γ and γ1 phases, with intermediate Nb contents there is a transitional phase γ1 (a superstructure of γ-TiAl). As for the influence of Al concentration on the phase relations. the γ1 phase was inclined to form in the alloys with relatively high Al contents. The ordering transformation of γ, to γ1 is a continuous ordering process and the transition may be second order.

关键词： TiAl nm PA Phase Relations in TiAl+Nb System Chen

Synthetic Control of Thorium metal-Organic Frameworks for Sequencing and Sensing of Radioiodine Species

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2024年第1期42卷 20-28,I0004页

作者： Yu Ju Zi-Jian Li xue wang Jie Qiu Yiuhon Chan zhi-Hui Zhang Mingyang He Jian lin Jiangsu key laboratory of advanced Catalytic materials and technology Changzhou UniversityNo.21Gehu Middle RoadChangzhouJiangsu 213164China Schoolof Nuclear science and technology Xi'an Jiaotong UniversityNo.28West Xianning RoadXianShaanxi 710049China key laboratoryof Interfacial Physics and technology Shanghai Institute of Applied PhysicsChinese Academy of Sciences2019JiaLuoRoadShanghai 201800China

Exploring the physiochemical properties and expanding the applications of actinide-containing materials is paramount to address the escalating challenge of radioactive waste ***,unlocking the full potential of these materials is largely crippled by the radiotoxicity of the *** report here two porous and luminescent thorium-based metal-organic frameworks(Th-BITD-1 and Th-BITD-2)that serve as a bifunctional platform for sequencing and sensing of radioiodine,a much more radioactive fission product discharged during the nuclear fuel *** particular,Th-BITD-1 displays better iodine uptake performance than Th-BITD-2 via the solution-based process and vapor diffusion with the maximum adsorption capacities of 831 and 1099 mg/g,*** thermore,Th-BITD-1 can function as a highly sensitive luminescence sensor for iodate with a quenching constant(Ksv)of 6.6(5)×10^(3) M^(-1)and a detection limit of 2.02μM,respectively,outperforming 2.96(6)×10^(3)M^(-1)and 10.5μM of ***,a positive correlation between the sensing efficacy and the iodate adsorption capacity has been *** work highlights the opportunity in designing novel actinide-based MOFs for their potential applications in radiological fields,e.g.,radionuclide separation and detection.

关键词： Thorium metal-organic frameworks Adsorption Detection lodine Actinides Radiochemistry Luminescence

Thermally modulated photoelectronic synaptic behavior in HfS_(2)/VO_(2) heterostructure

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

Rare metals 2024年第8期43卷 3798-3809页

作者： Le wang lin wang Xiao-Yun Ye Xiong-Hu Xu Li-Yan Shang Ya-Wei Li Jin-Zhong Zhang Liang-Qing Zhu zhi-Gao Hu Technical Center for Multifunctional Magneto-Optical Spectroscopy(Shanghai) Engineering Research Center of Nanophotonics&Advanced Instrument(Ministry of Education)Department of PhysicsSchool of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

Neuromorphic computing is known for its efficient computational speed,low latency,and reduced power consumption,which is considered a pivotal technology to overcome the von Neumann *** synapses are an indispensable component of neuromorphic computational artificial neural *** guarantee effective and precise processing of optical signals,it must have a high responsivity,detectivity,and the ability to adapt to various ***,a synaptic transistor based on the HfS_(2)/VO_(2) heterojunction with a responsivity of8.6×10^(3) A·W^(-1)and a detectivity of 1.26×10^(14)Jones at405 nm laser was ***,the typical synaptic behavior was successfully simulated,including postsynaptic currents(PSCs),the transition from shortterm plasticity(STP)to long-term plasticity(LTP).When VO_(2) converts from the semiconductor state to the metal state,the HfS_(2)/VO_(2) heterojunction transforms into a Schottky heterojunction from a TypeⅡheterojunction with ***'s important,the heterojunction still exhibits excellent responsivity and detectivity,as well as stability of synaptic *** addition,the classical Pavlovian conditioning experiment is simulated under different laser intensity to study the brain's associative learning *** results demonstrate that the HfS_(2)/VO_(2) heterojunction synapse exhibits significant responsivity and detectivity and is adaptable to high-temperature environments,showing great potential for neuromorphic computational applic ations.

关键词： HfS_(2) VO_(2) Phase transition Photoelectric synapse Heterojunction

Highly efficient and photothermally stable CDs@ZIF-8 for laser illumination

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第10期35卷 299-303页

作者： zhi wang lingpeng Yan Yelin Hao Jingxia Zheng Yongzhen Yang Xuguang Liu key laboratory of Interface science and Engineering in advanced materials Ministry of Education Taiyuan University of Technology College of materials science and Engineering Taiyuan University of Technology

Carbon dots(CDs), as a solid-state phosphor, have great potential for application in a new solid-state lighting device—laser diode(LD). For high efficiency LD devices, both high photoluminescence quantum yield(PLQY) and high photothermal stability of CDs are essential. Herein, yellow CDs@ZIF-8 composites with high structural stability were prepared by encapsulating CDs in zeolitic imidazolate framework-8(ZIF-8) through electrostatic adsorption between CDs and ZIF-8, in which CDs with amino groups on the surface were used as luminescent feeders and ZIF-8 was used as a protective layer matrix. The asprepared CDs@ZIF-8 not only possess a high PLQY of up to 81.17%, but also maintain a high fluorescence intensity of 100% and 80% under long-term illumination(60 min) and high temperature(478 K), respectively. The hydrogen bonding between CDs and ZIF-8 in the encapsulated structure can enhance the degree of electron cloud delocalization, which can improve the PLQY of CDs@ZIF-8. Meanwhile, CDs@ZIF-8has high photothermal stability due to the binding effect of ZIF-8 on CDs and high thermal stability of ZIF-8. The white LD device, fabricated from CDs@ZIF-8 as a phosphor in combination with 450 nm blue LD, has a color coordinate of(0.37, 0.33), a color temperature of 3762 K, and a high color rendering index of 86. This study provides a new strategy for the construction of solid-state phosphors with high PLQY and high photothermal performance.

关键词： Carbon dots High photoluminescence quantum yield High photothermal stability Laser illumination metal-organic frameworks