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Advance in the chemical synthesis and magnetic properties of nanostructured rare-earth-based permanent magnets

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Rare Metals 2013年第2期32卷 105-112页

作者： Ce yang yang-long Hou Department of Materials Science and Engineering College of EngineeringPeking University

Rare-earth-based permanent magnets are one of the most important magnets in both scientific and industrial fields. With the development of technology, nanostructured rarearth-based permanent magnets with high energy products are highly required. In this article, we will review the progress in chemical synthetic strategies of nanostructured rare-earth-based permanent magnets.

关键词： Rare-earth Permanent magnets Chemicalsynthesis

Excavator Energy-saving Efficiency Based on Diesel Engine Cylinder Deactivation Technology

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Chinese Journal of Mechanical Engineering 2012年第5期25卷 897-904页

作者： yang Jing QUAN long yang yang Key Laboratory of Advanced Transducers and Intelligent Control System of Ministry of Education Taiyuan University of Technology Taiyuan 030024 China The State Key Lab of Fluid Power Transmission and Control Zhejiang University Hangzhou 31002 7 China

The hydraulic excavator energy-saving research mainly embodies the following three measures： to improve the performance of diesel engine and hydraulic component, to improve the hydraulic system, and to improve the power matching of diesel-hydraulic system-actuator. Although the above measures have certain energy-saving effect, but because the hydraulic excavator load changes frequently and fluctuates dramatically, so the diesel engine often works in high-speed and light load condition, and the fuel consumption is higher. Therefore, in order to improve the economy of diesel engine in light load, and reduce the fuel consumption of hydraulic excavator, energy management concept is proposed based on diesel engine cylinder deactivation technology. By comparing the universal characteristic under diesel normal and deactivated cylinder condition, the mechanism that fuel consumption can be reduced significantly by adopting cylinder deactivation technology under part of loads condition can be clarified. The simulation models for hydraulic system and diesel engine are established by using AMESim software, and fuel combustion consumption by using cylinder-deactivation-technology is studied through digital simulation approach. In this way, the zone of cylinder deactivation is specified. The testing system for the excavator with this technology is set up based on simulated results, and the results show that the diesel engine can still work at high efficiency with part of loads after adopting this technology; fuel consumption is dropped down to 11% and 13% under economic and heavy-load mode respectively under the condition of driving requirements. The research provides references to the energy-saving study of the hydraulic excavators.

关键词： diesel engine cylinder deactivation hydraulic excavator energy-saving

Inversion of Seabed Geotechnical Properties in the Arctic Chukchi Deep Sea Basin Based on Time Domain Adaptive Search Matching Algorithm

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Journal of Ocean University of China 2024年第4期23卷 933-942页

作者： AN long XU Chong xing Junhui GONG Wei JIANG Xiaodian XU Haowei LIU Chuang yang Boxue Jiangsu Automation Research Institute Lianyungang 222061China Key Laboratory of Submarine Geosciences and Prospecting Techniques MOE and College of Marine GeosciencesOcean University of ChinaQingdao 266100China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdao 266071China

The chirp sub-bottom profiler,for its high resolution,easy accessibility and cost-effectiveness,has been widely used in acoustic *** this paper,the acoustic impedance and grain size compositions were obtained based on the chirp sub-bottom profiler data collected in the Chukchi Plateau area during the 11th Arctic Expedition of *** time-domain adaptive search matching algorithm was used and validated on our established theoretical *** misfit between the inversion result and the theoretical model is less than 0.067%.The grain size was calculated according to the empirical relationship between the acoustic impedance and the grain size of the *** average acoustic impedance of sub-seafloor strata is 2.5026×10^(6) kg(s m^(2))^(-1)and the average grain size(θvalue)of the seafloor surface sediment is 7.1498,indicating the predominant occurrence of very fine silt sediment in the study *** of the inversion results and the laboratory measurements of nearby borehole samples shows that they are in general agreement.

关键词： time domain adaptive search matching algorithm acoustic impedance inversion sedimentary grain size Arctic Ocean Chukchi Deep Sea Basin

Determination of solubility of uranium in liquid sodium

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Nuclear Science and Techniques 2008年第2期19卷 93-98页

作者： yang Tongzai xing Pifeng YE Shiyou long Kaiming FU Zhonghua HE Yuhui JIANG Tao Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China

An experimental technique has been developed which overcomes the two major problems common to liquid metal solubility measurements,namely,maintaining the integrity of the samples during transfer of the liquid sodium from container to whatever device is used for analysis and detecting solute at very low concentration in liquid *** solubility of uranium in liquid sodium has been measured over the temperature range 150～400℃,by equilibration and sampling technique,the solubility of uranium is approximately 0.00001%.

关键词：溶解度铀液态钠核技术

Stiffness Analysis of Spherical Parallel Mechanism U_(P+R) with 2-DOF

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Journal of Harbin Institute of Technology(New Series) 2013年第4期20卷 41-47页

作者： Yu-Lin Zhou long yang Bo Li Da-xing Zeng Feng Gao School of Mechanical Engineering Yanshan University XCMG Xuzhou Truck-Mounted Crane Co. Ltd. State Key Laboratory of Mechanical System and Vibration Shanghai Jiaotong University

As one of the typical less-mobility parallel mechanisms, the spherical parallel mechanism Up.s with two degrees of freedom （2-DOF） possess high order overconstraints, and the calculation of its stiffness is partly different with general parallel mechanisms owing to the bars in each branch are assumed to be arc-shaped. By means of small deformation superposition principle, the relationship between the angle displacement and line displacement of moving platform and the forces acted on the branches were derived out. Based on the results of static analysis, the relationship between the applied force, the line displacement and the angle displacement of the mechanism was set up. And then the stiffness matrix was obtained. The six principal stiffness of the mechanism and the corresponding directions were achieved by the orthogonal transformation. The numerical calculation was performed and the results showed that the principal stiffness and directions are varied with the pose-position of the mechanism, and the principal stiffness is gradually enlarged when it is far away from the anigin. In addition, the torsion stiffness is much greater and the line deformation stiffness is smaller, the difference between the two parts is huge. The research content of this paper supplies the theoretical foundation for the further engineering design and application of the spherical parallel mechanism.

关键词： spherical parallel mechanism static stiffness orthogonal transformation line displacement angle

Design Tide Hydrograph with A Given Risk Threshold by A Copula-Based Multivariate Method

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China Ocean Engineering 2017年第4期31卷 504-509页

作者： yang xing WANG Wei Hydraulic Research Institute of Jiangsu Nanjing 210017 China Jiangsu Water Conservancy Project Construction Bureau Nanjing 210029 China

This paper describes the development of a T-year design tide hydrograph （DTH）. A core innovation is that the proposed technique uses the design risk threshold and copula-based conditional risk probability to analyze the optimal combination of high waters and low waters of the DTH. A brief description of the method is presented. The in situ semi-diurnal tide data at the coast of Jiangsu Province in China are analyzed. Marginal distributions for high waters and low waters of tides are examined. Furthermore, the joint distributions, condition risk probabilities and risk thresholds of high waters and low waters are presented. Results of the DTH from the proposed method are compared with those from the traditional same-multiple enlarging design approach. It is demonstrated that the proposed method is preferable.

关键词： semi-diurnal tide design tide hydrograph marginal distribution joint distribution risk threshold copula

The Research on Safety Evaluation of High-pile Wharf Structure

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仪器仪表学报 2013年第S1期34卷 178-184页

作者： Li Jue long xing Jianchun Li Hairui yang Qiliang The Center for Coast Defense Engineering Research of Navy Institute of National Defense Engineering PLA University of Science & Technology

Due to a combination of the sea erosion,the ship collision,the change of ground condition,the effect of alternative static and dynamic load and the material deterioration,the structure of high-pile wharf is easily *** the structure of high-pile wharf destroyed,it is bound to be a great threat to the safety of various facilities and personnel in the *** all of that,the multi-level comprehensive evaluation method based on the extension theory is proposed in this *** this method to assess the safety of high-pile wharf structure,the reasonable advice on its maintenance and reinforcement can be given in ***’s more,the method is simple and can give more objective result of the evaluation.

关键词： high-pile wharf safety evaluation extension theory analytical hierarchy process

Gliding arc plasma adjusting pre-combustion cracking products

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Defence Technology（防务技术） 2022年第12期18卷 2198-2202页

作者： Fei-long Song Yun Wu Shi-da Xu xing-kui yang Jian-ping Zhou Xin Chen Science and Technology on Plasma Dynamics Laboratory Air Force Engineering UniversityXi'an710038China Institute of Aeroengine Xi'an Jiaotong UniversityXi'an710049China

In view of the difficulty of kerosene-air detonation faced by the application of rotating detonation to aviation engines,in order to improve the kerosene detonation activity,the atmospheric pressure gliding arc plasma is used to conduct secondary adjustment of the pre-combustion cracking *** results show that the components with larger molecular weight in the pre-combustion cracking products,such as ethylene and methane,can be cracked into highly active species of hydrogen and acetylene by gliding arc *** the increase of the fuel ratio of pre-combustion cracking,the plasma has a more significant effect on the adjustment of high active ***,as the flow rate of the cracking gas treated by plasma increases,the adjustment effect is obviously reduced.

关键词： Plasma adjustment Pre-combustion cracking Kerosene Detonation

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瓜州花西山金矿矿区特征及找矿前景

甘肃冶金 2017年第5期39卷 64-68页

作者：李世龙杨兴武冯小明薛同利马明甘肃省地矿局第三地质矿产勘查院甘肃兰州730050

花西山金矿床位于花牛山-金场沟多金属成矿带西段,是花牛山铅锌矿外围的小型金矿床。随着找矿工作的深入,发现金银铅锌多金属均在矿脉深部强烈富集,本矿床地质特征与花牛山铅锌矿床有相同性,矿(化)体受构造及岩浆岩控制。据矿区特征及... 详细信息

花西山金矿床位于花牛山-金场沟多金属成矿带西段,是花牛山铅锌矿外围的小型金矿床。随着找矿工作的深入,发现金银铅锌多金属均在矿脉深部强烈富集,本矿床地质特征与花牛山铅锌矿床有相同性,矿(化)体受构造及岩浆岩控制。据矿区特征及控矿因素分析,已知矿体深部及西部找矿潜力很大,具有较好的找矿前景,应进一步开展找矿工作,矿床通过进一步勘查有望发展为中型勘查开发基地的前景。

关键词：金银铅锌多金属矿床特征找矿前景花西山瓜州