检索结果-南通市图书馆

The effect of Ti and Zr content on the structure,mechanics and energy-release characteristics of Ti—Zr—Ta alloys

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第1期31卷 343-350页

作者： Jia-yu Meng Jing-zhi he Bin Zhang Jin chen Shun Li Dun Niu Yu Tang Xi’an Modern Chemistry Research Institute Xi'an710065China College of Aerospace Science and Engineering National University of Defense TechnologyChangsha410073China

Energetic structural materials(ESMs)are a new type of structural materials with bearing and damage *** this work the microstructure,mechanical properties and energy release characteristics of multi-element Ti-Zr-Ta alloys with good casting performance were *** microstructure of the Ti_(x)ZrTa alloys gradually change from BCC+HCP to single BCC structure with the increase of *** the Ti_(2)Zr_(y)Ta alloys was still uniform and single BCC structure with the increase of *** evolution of microstructure and composition then greatly affect the mechanical properties and energy-release characteristics of Ti-Zr-Ta *** synergistic effect of dual phase structure increases the fracture strain of Ti_(x)ZrTa(x=0.2,0.5)with the Ti content decreases,while the fracture strain of Ti_(x)ZrTa(x=2.0,3.0,4.0)gradually increase with the Ti content increases caused by the annihilation of the obstacles for dislocation *** as Zr content increases,the fracture strain of Ti_(2)Zr_(y)Ta alloys decrease,then the oxidation reaction rate and fragmentation degree gradually *** higher oxidation rate and the lager exposed oxidation area jointly leads the higher releasing energy efficiency of Ti_(x)ZrTa alloys with low Ti content and Ti_(2)Zr_(y)Ta alloys with high Zr content.

关键词： Energetic structural materials Ti-Zr-Ta Multi-element alloy Energy release characteristics

Adaptive modulation MIMO system based on minimizing transmission power

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第6期7卷 1046-1050页

作者： WANG zhi-ying he chen Department of Electronics Engineering Shanghai Jiao Tong University Shanghai 200240 China

Adaptive modulation (AM) is an effective technique to approach the theoretical bound of multi-input and multi-output (MIMO) channel. In most previous studies, the AM parameters were obtained by maximizing the transmission rate for a given total transmit power. In this paper, a novel AM-MIMO algorithm is presented, which is based on minimizing total transmit power when the link’s QoS requirements are given. By taking the QoS requirements into account directly, the proposed algorithm not only makes the system more flexible, but also makes the cross layer design of wireless network easier. At last, the numerical results of the proposed scheme are presented.

关键词：自适应调制 MIMO系统 QoS 极小化发射功率

Topological pseudospin switcher:Mechanism and acoustic realization

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 46-53页

作者： Jia-he chen Yiyin chen Yaoqieyu Song Yongxu Xu Xinrong Li Jingsong Wang Jiawei he Jiaxu Qu Zheng Li Xiaofei Li Wenqiang Lin Jiannan chen Caixing Fu zhi Hong Hang School of Physical Science and Technology&Collaborative Innovation Center of Suzhou Nano Science and Technology Soochow UniversitySuzhou 215006China Institute for Advanced Study Soochow UniversitySuzhou 215006China Provincial Key Lab of Thin Films Soochow UniversitySuzhou 215006China

The control of the pseudospin of sound wave has attracted increasing attention in recent *** the finite-size effect of topological acoustics,we successfully construct an H-shaped acoustic topological pseudospin switcher that sound wave energy can be easily switched through different *** interesting phenomenon of pseudospin flipping is numerically and experimentally demonstrated.A quantitative interference theory is proposed that the constructive and destructive interference of pseudospin states leads to pseudospin flipping and preserving in multiple *** verify the key parameters of the design,including the length of the passage and its interface state dispersion,and the theory can be extended to other topology acoustics and photonics ***,the tunable topological sonic crystal we use provides adjustable convenience to pseudospin switcher *** pseudospin switching behavior offers an efficient method to control the acoustic topological edge state transport,which has great potential in versatile applications,such as integrated acoustics,acoustic security,and information processing.

关键词： topological acoustics realization

Energy partition in laser-induced cavitation bubbles near the rigid wall with a gas-containing hole

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2024年第3期36卷 435-443页

作者： Dong-qiao he Hai-gang Wen Si-yuan Geng chen-xi Yang Qiang Zhong zhi-feng Yao College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China PowerChina Beijing Engineering Corporation Limited Beijing100024China State Key Laboratory of Efficient Utilization of Agricultural Water Resources Beijing100083China Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System China Agricultural UniversityBeijing100083China

To investigate the energy partition in laser-induced cavitation bubbles near the rigid wall with a gas-containing hole,we utilized a nanosecond resolution photography system based on a Q-switched Nd:YAG laser and conventional industrial camera to carefully observe the transient process of bubble collapse near the rigid wall with a gas-containing *** analyzed the generation of collapse microjets and the emission of collapse shock *** found that the cavitation bubble near the rigid wall with a gas-containing hole collapsed at different times and space,and produced various types of shock *** on the far field pressure information of the shock waves measured by hydrophone,the energy of the shock waves generated by the bubble collapse near the rigid wall with a gas-containing hole is calculated for the first *** results show that the ratio of collapse shock wave energy to bubble energy is approximately between 0.7 and 0.8.

关键词： Energy partition bubble collapse laser-induced shock wave gas-containing hole

Novel P-doping-tuned Pd nanoflowers/S,N-GQDs photo-electrocatalyst for high-efficient ethylene glycol oxidation

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

Chinese Chemical Letters 2024年第6期35卷 541-545页

作者： Xiaoxiao Huang zhi-Long he Yangpeng chen Lei Li Zhenyu Yang Chunyang Zhai Mingshan Zhu School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China College of Biological Chemical Sciences and EngineeringJiaxing UniversityJiaxing 314001China Guangdong Key Lab oratory of Environmental Pollution and health School of EnvironmentJinan UniversityGuangzhou 510632China

Traditional photo-electcatalyst structures of small noble metal nanoparticles assembling into large-scale photoactive semiconductors still suffer from agglomeration of noble metal nanoparticles,insufficient charge transfer,undesirable photoresponse ability that restricted the photo-electrocatalytic *** this end,a novel design strategy is proposed in this work,namely integrating small-scale photoactive materials(doped graphene quantum dots,S,N-GQDs)with large-sized noble metal(Pd P)nanoflowers to form novel photo-electrocatalysts for high-efficient alcohol oxidation *** expected,superior electrocatalytic performance of Pd P/S,N-GQDs for ethylene glycol oxidation is acquired,thanks to the nanoflower structure with larger specific surface area and abundant active ***,nonmetal P are demonstrated,especially optimizing the adsorption strength,enhancing the interfacial contact,reducing metal agglomeration,ensuring uniform and efficient doping of S,N-GQDs,and ultimately significantly boost the catalytic activity of photo-electrocatalysts.

关键词： Non-metallic P–doping Sulfur nitrogen co-doped graphene quantum dots Pd nanoflowers Photo-electrocatalytic Ethylene glycol oxidation

Characteristics and main controlling factors of helium resources in the main petroliferous basins of the North China Craton

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2024年第2期43卷 23-33页

作者： Zihan Gao zhi chen Hongyi he Zhaofei Liu Chang Lu Hanyu Wang Yili Luo Ying Li Institute of Earthquake Forecasting China Earthquake AdministrationBeijing 100036China College of Geosciences China University of Petroleum-BeijingBeijing 102249China School of Earth Science and Resources China University of Geosciences(Beijing)Beijing 100083China

At present, the main controlling factors of helium accumulation is one of the key scientific problems restricting the exploration and development of helium reservoir. In this paper, based on the calculation results of he generation rate and the geochemical characteristics of the produced gas, both the similarities and differences between natural gas and he resources in the Bohai Bay, Ordos and the surrounding Songliao Basin are compared and analyzed, discussing the main controlling factors of helium resources in the three main petroliferous basins of the North China Craton. It is found that the three basins of Bohai Bay, Ordos and Songliao have similar characteristics of source rocks, reservoirs and cap rocks, that's why their methane resource characteristics are essentially the same. The calculated ~4he generation per cubic metamorphic crystalline basement in the three basins is roughly equivalent, which is consistent with the measured he resources, and it is believed that the ~4he of radiogenic from the crust is the main factor controlling the overall he accumulation in the three basins;there is almost no contribution of the mantle-derived CH_4, which suggests that the transport and uplift of mantle-derived ~3he carried by the present-day magmatic activities along the deep-large faults is not the main reason for the mantle-derived ~3he mixing in the basins. Combined with the results of regional volcanic and geophysical studies,it is concluded that under the background of the destruction of North China Craton, magma intrusion carried a large amount of mantle-derived material and formed basic volcanic rocks in the Bohai Bay Basin and Songliao Basin, which replenished mantle-derived ~3he for the interior of the basins, and that strong seismic activities in and around the basins also promoted the upward migration of mantle source ~3he. This study suggests that the tectonic zone with dense volcanic rocks in the Cenozoic era and a high incidence of historical strong ear

关键词： helium Bohai Bay Basin destruction of the North China Craton fault Cenozoic volcanic rocks strong earthquake activity

Fully Nonlinear Equations of Krylov Type on Riemannian Manifolds with Totally Geodesic Boundary

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2024年第5期40卷 1293-1307页

作者： Li chen Yan he Faculty of Mathematics and Statistics Hubei Key Laboratory of Applied MathematicsHubei UniversityWuhan 430000P.R.China

In this paper,we study fully nonlinear equations of Krylov type in conformal geometry on compact smooth Riemannian manifolds with totally geodesic *** prove the a priori estimates for solutions to these equations and ... 详细信息

关键词： The modified Schouten tensor k-convex hessian type equation

Prediction of liquid circulation flow rate in RH degasser:improvement of decarburization at low atmospheric pressure

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research(International) 2024年第7期31卷 1661-1667页

作者： Gu-jun chen Sheng-ping he College of Materials Science and Engineering Yangtze Normal UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

The two-fluid model coupled with population balance model was used for simulating the gas-liquid flow in the Ruhrstahl-heraeus(RH)*** predicted circulation flow rate was compared with that measured from a water model experiment to validate the mathematical ***,influence of snorkel immersion depth on liquid circulation flow rate was numerically investigated under an atmospheric pressure of 101 and 84 kPa,*** result indicates that the circulation flow rate of the RH degasser in the high-altitude area was severely reduced because of the decrease in atmospheric ***,increasing the snorkel immersion depth from 0.5 to 0.7 m can compensate for the decrease in atmospheric *** test result indicates that decarburization rate is significantly enhanced by increasing the snorkel immersion *** optimization,the percentage of heats with a final carbon content less than 0.002 wt.%is significantly increased from 22.0%to 96.4%.

关键词： RH degasser Two-fluid model Population balance model-Circulation flow rate Decarburization Snorkel immersion depth

Effects of sediment particle morphology on adsorption of phosphorus elements

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

International Journal of Sediment Research 2013年第2期28卷 246-253页

作者： Hong-wei FANG Ming-hong chen zhi-he chen Hui-ming ZHAO Guo-jian he Department of Hydraulic Engineering the State Key Laboratory of Hydro Science and EngineeringTsinghua University College of Water Resources and Civil Engineering China Agricultural University Department of Water Resources and Environment Sun Yat-sen University

Sediment particle surface morphology affects phosphorus *** paper studied the phosphorus adsorption on sediment particle by using a Scanning Electron Microscope(SEM) and an Energy Dispersive X-ray Spectroscopy (EDS).Sediment samples from the Yangtze,Yellow and Yongding rivers in China were chosen to measure the particle surface morphology,surface gray scale and element distribution *** samples were firstly cleaned and put into phosphate solution for *** the Langmuir equation and Freundlich equation were used for descriptions of adsorption-desorption isotherms for *** were then dried and *** results show that the adsorption of phosphorus depends on the surface morphology of *** exists mostly in the ridges and channels,while a few exist in the slopes,and casually in the peaks,passes and pits.

关键词： Surface morphology Scanning electron microscope Adsorption Element distribution