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Risk assessment of hazardous materials transportation:A review of research progress in the last thirty years

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Journal of Traffic and Transportation Engineering(English Edition) 2022年第4期9卷 571-590页

作者： Jian Guo cheng luo College of Civil Engineering Zhejiang University of TechnologyHangzhou 310023China School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China

In recent years,hazardous materials transportation accidents occur frequently,causing huge casualties and property *** assessment of hazardous materials transportation has been constantly investigated by researchers and *** order to study the research progress of risk assessment of hazardous materials transportation,so as to better reveal relevant *** review systematically analyzes the existing literature,from 1991 to 2020,on risk assessment models and methods of hazardous materials transportation,and segregates the relevant studies based on unimodal and intermodal transportation ***,an example is considered to analyze the characteristics of each risk assessment model of unimodal transportation,and a novel detailed classification is proposed for the risk assessment *** results indicate that the research on the risk assessment model of road transportation of hazardous materials is comprehensive,whereas that based on the railway and intermodal transportations is *** comparison with the traditional risk assessment model,the conditional value-at-risk model presents a flexible decision-making framework for decision-makers and controls risk preference between risk neutrality and risk *** to the difficulty in achieving door-to-door railway transportation and the increased risks associated with the intermodal transportation,the conclusion that the risk of railway and multimodal transportation of hazardous materials is lower than that of road transportation is not *** operators and governments can combine the advantages of different transportation modes,such as low risk,low cost,high flexibility,and high reliability,to achieve public safety and improve the competence of the *** on the proposed classification,this review identifies the existing trends and research gaps and summarizes future research directions.

关键词： Transportation Hazardous materials Risk assessment Transportation modes Risk model

Multiple Jacobi Elliptic Function Solutions to Integrable Higher Order Broer-Kaup Equation in （2＋1）-Dimensional Spaces

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Communications in Theoretical Physics 2006年第2X期46卷 193-198页

作者： LI De-Sheng luo cheng-Xin College of Mathematics and Systems Science Shenyang Normal University Shenyang 110034 China

In this paper, we improve the method for deriving Jacobi elliptic function solutions of nonlinear evolution equations given in Ref. [12] and apply it to the integrable higher-order Broer-Kaup system in （2＋1）-dimens... 详细信息

关键词： Jacobi elliptic function projective Riccati equation higher-order Broer-Kaup system exact solutions

Nickel-Catalyzed Dicarbofunctionalization of Alkenes

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Chinese Journal of Chemistry 2020年第11期38卷 1371-1394页

作者： Yun-cheng luo Chang Xu Xingang Zhang Key Laboratory of Organofluorine Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling LuShanghai 200032China

As a straightforward strategy for rapidly increasing molecular complexity,dicarbofunctionalization of alkenes has attracted substantial interests of organic synthesis,medicine chemistry,and materials ***-catalyzed cascade dicarbofunctionalizations have been flourished in this area recently,and nickel-mediated radical pathways particularly offer new opportunities in conjunctive cross-couplings with alkyl coupling ***,we give a comprehensive review of nickel-catalyzed dicarbofunctionalization of alkenes through a historical perspective,including intermolecular three-component reactions and intramolecular cascade *** the pathways discussed in this review,the carbometallation/cross-coupling process and the radical addition/cross-coupling process are the two major pathways for the nickel-catalyzed dicarbofunctionalization of *** oxidative cyclization and 1,2-metallate shift processes are also selectively *** methods overcome the limitations associated with the reactions using noble metals in the field,providing an efficient and straightforward access to structurally diversified molecules.

关键词： nickel straight catalyzed

Participation of large-scale wind power generation in power system frequency regulation

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Chinese Science Bulletin 2013年第36期58卷 4557-4565页

作者： SUN HaiShun LIU Ju WEN JinYu cheng ShiJie luo cheng YAO LiangZhong State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and Technology Midwest Independent Transmission System Operator Inc. China Electric Power Research Institute

The initiative participation of wind power generators in power system frequency regulation is an inevitable demand to ensure power system safe operation with large-scale wind power ***,it is principally difficult for conventional wind turbines to participate in power system frequency *** this reason,solution to this problem is becoming a hot topic in the current *** paper systematically reviews the relevant research progresses in the control strategies and the capability assessment of using wind power generators in the power system frequency regulation,including the comparing among the emulating inertia control,the droop control,the rotor speed control,the pitch angle control and the coordinated ***,future research in this area is pointed out in the paper.

关键词：风力发电机电力系统频率调节控制策略风力涡轮机安全运行惯性控制转速控制

Chaotic Unilateral Weighted Backward Shifts on Sequentially Complete Topological Sequence Spaces

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Acta Mathematica Sinica,English Series 2022年第7期38卷 1285-1293页

作者： Zhen RONG cheng luo Fei HE Ning LU College of Statistics and Mathematics Inner Mongolia University of Finance and EconomicsHohhot 010070P.R.China School of Mathematical Sciences Inner Mongolia UniversityHohhot 010021P.R.China

Extending previous results of Grosse-Erdmann and Peris we obtain a characterization of chaotic unilateral weighted backward shifts on sequentially complete topological sequence spaces in which the canonical unit vecto... 详细信息

关键词： Chaotic operators topological sequence spaces unilateral weighted backward shifts

Transformation toughening in zirconium tantalum ceramics

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Science China(Technological Sciences) 2022年第8期65卷 1772-1779页

作者： LI Cong TAN Dan luo cheng luo JunHui CAO Ke YANG Li ZHOU YiChun School of Advanced Materials and Nanotechnology Xidian UniversityXi’an 710126China Frontier Research Center of Thin Films and Coatings for Device Applications Academy of Advanced Interdisciplinary ResearchXidian UniversityXi’an 710126China School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105China

Toughness enhancement of zirconium tantalum ceramics is conducive to the new generation of thermal barrier coatings(TBCs).The phase transformation toughening mechanism of zirconium tantalum ceramics has been explored through the Vickers indentation of YTaO_(4) ceramic block,the phase transformation region is found near the indentation and the microcrack *** increased energy of stable phaseΔE_(M.M′)>0,and the volume expandedΔV≈1.9%,so,the phase transformation is a process of energy *** additional stressσa restraining the crack propagation was generated in the shielding area at the crack *** addition,combined with the toughening of ferroelastic domains switch,the traditional microcrack toughening,and crack propagation toughening,we summarized the toughening mechanism of YTaO_(4) ceramics with the increasing external load,which is followed by ferroelastic toughening,phase transformation,microcrack,and crack *** the perspective of toughening,we found that Z^(4+) doping in YTaO_(4) ceramics could broaden the phase transformation range in phase transformation toughening,significantly improve the toughness and reduce the generation of cracks in microcrack toughening and crack propagation ***,toughening mechanism of zirconium tantalum ceramics has important guiding significance for the service of TBCs.

关键词： transformation toughening crack tip YTaO_(4)ceramics toughening mode

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Numerical simulation of temperature field of AZ91D magnesium alloy during equal channel angular extrusion

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Acta Metallurgica Sinica(English Letters) 2010年第1期23卷 35-40页

作者： Xiaohua ZHANG Yuansheng cheng Shouting luo School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

The temperature field of AZ91D magnesium alloy extruded by equal channel angular extrusion （ECAE） has been simulated using finite element method （FEM）. A series of tests were designed to obtain the simulation parameters： flow stress of AZglD, friction factor and heat transfer coefficient. The simulated temperature agrees well with the measured one. The evolution of temperature and influencing factor was discussed in details. Furthermore. the extrusion pressure of ECAE was analyzed.

关键词： Simulation Temperature field ECAE AZ91D Magnesium alloy

Metamorphic Skarns in the Yangla Cu Ore Field,Northwest Yunnan Province,China

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Journal of Earth Science 2018年第3期29卷 508-519页

作者： Yanxiong Mei Zhenfei Zhang Yuanjin Xu cheng luo Institute of Mineral Resources Chinese Academy of Geological SciencesBeijing 100037China Institute of Mathematical Geology and Remote Sensing China University of GeosciencesWuhan 430074China Mining Development Co.Ltd. DiqingShangrila 674400China

The Yangla Copper Ore Field in Northwest Yunnan Province, China, is a large region of deposits dominated by copper-bearing skarns whose origin remains debatable despite numerous studies over the past two decades. We have investigated the geological and geochemical characteristics of the skarns using field and microscopic observations combined with chemical analyses. The results show that the skarns fall into two categories. The first category is metamorphic skarn, which constitute the majority （〉90%） of skarns in the deposit and is characterized by stratiform occurrences conformable to Devonian host strata, anhydrous mineral assemblages such as diopside＋hedenbergite＋quartz, widespread banded structure, fine-grainsize （〈200 μm） and preserved tuff-like textures. Whole-rock major element compositions, REE and trace-element compositions resemble those of the country rock slates or schists. The skarn layers occur at variable distances （0-2 000 m） from Indosinian plutonic bodies. Fracture-filling veins and/or alteration halos are scarce or absent in or near the skarn layers. This category of skarn probably formed by isochemical contact metamorphism of fine calcareous clastic sediments or impure carbonate rocks during emplacement of the plutonic bodies with no significant material migration by hydrothermal fluids involved during the process, in which case metallic enrichment of the skarn layers was present in the protolith of the skarn. The second category is metasomatic skarn with relatively coarse-grained textures （200-〉1 000 μm） and volatile-reach assemblages such as diopside＋tremolite＋scapolite at or near the igneous contact zones, which constitutes only a minor pro-portion of ore compared with metamorphic skarn. Taking into consideration diverse existing opinions about the genetic type of the deposit, we suggest that the geological and whole-rock geochemical characteristics of the skarus are consistent with a metamorphosed and metasomatized SEDEX （sedimentary exhalati

关键词： metamorphic skarn mineral deposit Yangla Copper Ore Field ore genesis.

Simulation and Analysis of Crashworthiness of Fuel Tank for Helicopters

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Chinese Journal of Aeronautics 2007年第3期20卷 230-235页

作者： luo cheng LIU Hua YANG Jia-ling LIU Kai-xin Institute of Solid Mechanics Beijing University of Aeronautics and Astronautics Beijing 100083 China Department of Mechanics and Engineering Peking University Beijing 100871 China

Crashworthiness requirement of fuel tanks is one of the important requirements in helicopter designs. The relations among the protection frame, textile layer and rubber layer of the fuel tank are introduced. Two appropriate FE models are established, one is for an uncovered helicopter fuel tank without protection frame, and the other is for fuel tank with protection frame. The dynamic responses of the two types of fuel tanks impinging on the ground with velocities of 17.3 m/s are numerically simulated for the purpose of analyzing energy-absorbing capabilities of the textile layer and protection frame. The feasibility of the current crashworthiness design of the fuel tank is examined though comparing the dynamic response behaviors of the two fuel tanks.

关键词： fuel tank crashworthiness helicopter FEM