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Acta Mathematicae Applicatae Sinica 2018年第3期34卷 451-468页

作者： cong-cong xu Zuo-liang xu School of Information Renmin University of China Beijing 100872 China Department of Basic Course Shijiazhuang Institute of Railway Technology Shijiazhuang 050041 China

We use an actuarial approach to estimate the valuation of the reload option for a non-tradable risk asset under the jump-diffusion processes and Hull-White interest rate. We verify the validity of the actuarial approach to the European vanilla option for non-tradable assets. The formulas of the actuarial approach to the reload option are derived from the fair premium principle and the obtained results are arbitrage. Numerical experiments are conducted to analyze the effects of different parameters on the results of valuation as well as their differences from those obtained by the no-arbitrage approach. Finally, we give the valuations of the reload options under different parameters.

关键词： Non-tradable assets reload option actuarial approach jump-diffusion processes stochastic inter-est rate

Flow and clogging in a horizontal silo with a rotary obstacle

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Chinese Physics B 2023年第4期32卷 467-472页

作者：徐聪聪史庆藩刘伟郑宁 School of Physics Beijing Institute of TechnologyBeijing 100081China

The external perturbation applied to a silo and the placement of an immobile obstacle before an exit are two common and effective ways to diminish clogging in the hopper/silo ***,we incorporate the local perturbation into a fixed obstacle,and experimentally explore the effects of a rotary obstacle on clogging and the flowing characteristics in the horizontal silo flow driven by a conveyor *** with a low spin rate,the total blocking probability that a particle constructs a stable blocking arch with its neighbors significantly ***,the average flow rate of the particles through the exit abruptly rises,at least 1 order of magnitude better than that with an immobile obstacle and approaching the flow rate of continuous *** rotation enhances the breakage of clogging arches,which is responsible for improving the flowability in the horizontal *** addition,there always exists an optimal obstacle position at which the total blocking probability is minimal and the average flow rate peaks,regardless of the spin ***,clogging is relieved with the increase of the driving velocity of the conveyor belt,showing a“fast is fast”effect that is opposite to the“fast is slow”effect in other systems such as crowd evacuation and gravity-driven hoppers.

关键词： granular flow clogging obstacle rotation

Cutaneous Radiation-Associated Angiosarcoma After Cervical Cancer Treatment:A Case Report

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International Journal of Dermatology and Venereology 2021年第4期4卷 263-265页

作者： cong-cong xu Wei Zhang Hao Chen Department of Pathology Hospital for Skin Diseases(Institute of Dermatology)Chinese Academy of Medical Sciences and Peking Union Medical CollegeNanjingJiangsu 210042China

Introduction:Cutaneous radiation-associated(cRAA)angiosarcoma is a rare malignant neoplasm derived from vascular endothelial cells,but a relatively commonly recognized complication of radiation ***,we present a patient with cRAA,who undergone radiochemotherapy for cervical cancer 11 years *** presentation:A 48-year-old woman presented with a 6-month history of painless purple skin plaques and nodules on her lower abdomen and right *** patient had undergone radiochemotherapy for cervical cancer 11 years ago.A skin biopsy showed a diffuse proliferation of irregular anastomosing dilated vascular structures with atypical endothelial *** was diagnosed as cRAA according to clinical and histological ***:cRAA is a rare malignant neoplasm but it is a complication of radiation *** incidence of cRAA has increased in recent *** and pathological manifestations are highly *** resection is the preferred ***:Patients with suspicious violaceous lesions should undergo *** suspicion and pathological examination are of the utmost importance for cRAA.

关键词： cutaneous angiosarcoma radiation therapy

Overview of in-situ oxygen production technologies for lunar resources

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 233-255页

作者： Youpeng xu Sheng Pang Liangwei cong Guoyu Qian Dong Wang Laishi Li Yusheng Wu Zhi Wang College of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China CAS Key Laboratory of Green Process and Engineering National Engineering Research Center for Green Recycling of Strategic Metal ResourcesInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial ***,crucial for supporting human life on the Moon,can be extracted from lunar regolith,which is highly rich in oxygen and contains polymetallic *** oxygen and metal extraction can be achieved using existing metallurgical ***,the ample reserves of water ice on the Moon offer another means for oxygen *** paper offers a detailed overview of the leading technologies for achieving oxygen production on the Moon,drawing from an analysis of lunar resources and environmental *** delves into the principles,processes,advantages,and drawbacks of water-ice electrolysis,two-step oxygen production from lunar regolith,and one-step oxygen production from lunar *** two-step methods involve hydrogen reduction,carbothermal reduction,and hydrometallurgy,while the one-step methods encompass fluorination/chlorination,high-temperature decomposition,molten salt electrolysis,and molten regolith electrolysis(MOE).Following a thorough comparison of raw materials,equipment,technology,and economic viability,MOE is identified as the most promising approach for future in-situ oxygen production on the *** the corrosion characteristics of molten lunar regolith at high temperatures,along with the Moon's low-gravity environment,the development of inexpensive and stable inert anodes and electrolysis devices that can easily collect oxygen is critical for promoting MOE technology on the *** review significantly contributes to our understanding of in-situ oxygen production technologies on the Moon and supports upcoming lunar exploration initiatives.

关键词： lunar resources in-situ oxygen production space metallurgy molten lunar regolith electrolysis

优化配矿强化西澳超细粒磁铁精矿球团焙烧研究

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工程科学学报 2017年第5期39卷 683-692页

作者：朱德庆虎训潘建杨聪聪徐梦杰王召元中南大学资源加工与生物工程学院长沙410083 北方重工集团(沈阳)工程设计研究院有限公司沈阳110027

进行了西澳超细粒磁铁精矿分别配加国产磁铁精矿和巴西赤铁精矿制备氧化球团矿的实验研究.结果表明,以100%西澳超细磁铁精矿为原料制备氧化球团矿时,球团预热及焙烧性能较差,在预热温度为1050℃、预热时间20 min及焙烧温度1300℃、焙烧... 详细信息

进行了西澳超细粒磁铁精矿分别配加国产磁铁精矿和巴西赤铁精矿制备氧化球团矿的实验研究.结果表明,以100%西澳超细磁铁精矿为原料制备氧化球团矿时,球团预热及焙烧性能较差,在预热温度为1050℃、预热时间20 min及焙烧温度1300℃、焙烧时间40 min的条件下,预热球团和焙烧球团矿抗压强度分别为每个502和2313 N.西澳超细粒磁铁精矿配加40%国产磁铁精矿或20%巴西赤铁精矿时,球团适宜预热温度由1050℃分别降低到950和975℃,适宜的焙烧温度由1300℃分别降低到1250和1280℃;而且焙烧球团矿的抗压强度分别提高到每个2746 N和每个2630 N.焙烧球团矿的微观结构研究表明:配加国产磁铁精矿后,焙烧球团矿中Fe_2O_3晶粒发育优良,晶粒间互联程度提高,晶粒粗大,孔隙率低,固结更加紧密.配加20%巴西赤铁精矿时,焙烧球团矿中Fe_2O_3晶粒基本连接成片,Fe_2O_3晶体发育良好.优化配矿是改善西澳超细粒磁铁精矿球团矿预热及焙烧性能的有效途径.

关键词：西澳超细粒磁铁精矿球团预热焙烧磁铁精矿赤铁精矿优化配矿

Molecular simulation study of the microstructures and properties of pyridinium ionic liquid[HPy][BF_(4)]mixed with acetonitrile

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原子与分子物理学报 2025年第4期42卷 27-32页

作者： xu Jian-Qiang MA Zhao-Peng CHENG Si LIU Zhi-cong ZHU Guang-Lai Department of Physics School of Physics and Electronic InformationAnhui Normal UniversityWuhu 241002China

The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this *** following properties were determined:density,self-diffusion coefficient,excess molar volume,and radial distribution *** results show that with an increase in the mole fraction of[HPy][BF_(4)],the self-diffusion coefficient ***,the excess molar volume initially decreases,reaches a minimum,and then *** rules of radial distribution functions(RDFs)of characteristic atoms are *** increasing the mole fraction of[HPy][BF_(4)],the first peak of the RDFs of HA1-F decreases,while that of CT6-CT6 rises at first and then *** indicates that the solvent molecules affect the polar and non-polar regions of[HPy][BF_(4)]differently.

关键词： Pyridinium ionic liquids Thermodynamic properties Molecular dynamics simulation Radial distribution functions

Venturi-type fluidic sampler for liquid-solid mixtures

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Particuology 2012年第3期10卷 283-291页

作者： cong xu Binbin Liu Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China

Static-type samplers are required for sampling corrosive, toxic, high-temperature, or radioactive liquid-solid fluids. We have designed a compact reverse flow diverter pumping system for transferring liquid-solid mixtures. In accordance with the Venturi principle, an acceptable volume of liquid-solid fluid is automatically collected into a sampling bottle. The effects of sampling needle sizes, sectional area of the T-section, solid concentration, and liquid viscosity on the performance of fluidic samplers were experi- mentally investigated. The sample volume increased upon the reduction of the sampling needle length and the increase of the sectional area of the T-section, but decreased with the increase of solid concentration and liquid viscosity. Unbiased samples of acceptable volume were produced by the proposed fluidic sampler, even at 10.21 mPa s liquid viscosity, 35 wt% solid concentration, and 6.74 m sampling height.

关键词： SamplerLiquid-solid Reverse flow diverterVenturi principle Maintenance free

A risk assessment method considering risk attributes and work safety informational needs and its application

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Chinese Journal of Chemical Engineering 2024年第4期68卷 253-262页

作者： cong Luo Yunsheng Zhao Ke xu School of Political Science and Public Administration Shandong UniversityQingdao 266200China Faculty of Engineering China University of GeosciencesWuhan 430074China Department of Emergency Management of Hubei Province Wuhan 430064China

The technological revolution has spawned a new generation of industrial systems,but it has also put forward higher requirements for safety management accuracy,timeliness,and *** assessment needs to evolve to address the existing and future challenges by considering the new demands and advancements in safety *** study aims to propose a systematic and comprehensive risk assessment method to meet the needs of process system safety *** methodology first incorporates possibility,severity,and dynamicity(PSD)to structure the“51X”evaluation indicator system,including the inherent,management,and disturbance risk ***,the four-tier(risk point-unit-enterprise-region)risk assessment(RA)mathematical model has been established to consider supervision *** in conclusion,the application of the PSD-RA method in ammonia refrigeration workshop cases and safety risk monitoring systems is presented to illustrate the feasibility and effectiveness of the proposed PSD-RA method in safety *** findings show that the PSD-RA method can be well integrated with the needs of safety work informatization,which is also helpful for implementing the enterprise's safety work responsibility and the government's safety supervision responsibility.

关键词： Risk assessment Safey “51X”evaluation indicator system Four-tier risk assessment model Risk attributes Process system

A comparative study on Sn macrosegregation behavior of ternary Al-Sn-Cu alloys prepared by gravity casting and squeeze casting

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China Foundry 2023年第1期20卷 63-70页

作者： Ming xu Yan-guo Yin cong-min Li cong-chong Duan College of Mechanical Engineering Hefei University of TechnologyHefei 230002China Anhui Yihui New Materials Co. Ltd.Hefei 230000China

A comprehensive study on Sn macrosegregation behavior in ternary Al-Sn-Cu alloys was carried out by comparative analysis between gravity casting and squeeze casting *** microstructure and Sn distribution of the castings were characterized by metallography,scanning electron microscopy(SEM),energy-dispersive X-ray(EDX)spectroscopy,and a direct reading *** show that there are obvious differences in Sn morphology between gravity casting and squeeze casting *** squeeze casting condition,the grain size of the casting is smaller and the distribution ofβ(Sn)is *** effectively reduces the segregation of triangular grain boundary as well as the segregation of *** segregation types of Sn in gravity casting and squeeze casting samples are obviously *** upper surfaces of gravity casting samples show severe negative segregation,while all the lower surfaces have positive *** with gravity casting,squeeze casting solidifies under isostatic *** to the direct contact between the upper surface of the casting and the mold,the casting solidifies faster under higher undercooling degree and ***,the uniform distribution of Sn reduces the segregation phenomenon on the surface of the casting.

关键词： ternary Al-Sn-Cu alloy squeeze casting macrosegregation mechanism

Synthesis and Microphase Separation Behavior of Random, Mixed Cylindrical Brush Copolymers Bearing Polystyrene and Poly(ε-caprolactone) Side Chains

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Chinese Journal of Polymer Science 2017年第12期35卷 1572-1586页

作者： Houluo cong Sen xu 郑思珣 Department of Polymer Science and Engineering and the State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong University

A series of mixed, random cylindrical brush copolymers bearing polystyrene（PS） and poly（ε-caprolactone）（PCL） side chains were synthesized via the combination of ring-opening polymerization（ROP） and atom transfer radical polymerization（ATRP）. These novel cylindrical brush copolymers have been characterized by means of nuclear magnetic resonance（NMR） spectroscopy, gel permeation chromatography（GPC） and differential scanning calorimetry（DSC）. It was found that the mikto-armed cylindrical brush copolymers were microphase-separated in bulks and that the morphologies were dependent on the mass ratios of PS to PCL side chains. One of the cylindrical brush copolymers was employed to incorporate into epoxy thermoset to investigate effect of the mikto-armed cylindrical brush architecture on the reaction-induced microphase separation behavior. Depending on the concentration of the cylindrical brush in epoxy, the thermosets can display the morphologies with the spherical, worm-like and lamellar PS microdomains dispersing in continuous thermosetting matrices.

关键词： Cylindrical brush copolymers Block copolyrner Epoxy Reaction-induced microphase separation