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Application of low-temperature thermochronology on ore deposits preservation framework in South China:a review

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Acta Geochimica 2022年第2期41卷 165-184页

作者： kang min Jian-Feng Gao State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China

South China can be divided into four metallogenic belts:The Middle-Lower Yangtze Metallogenic Belt(MLYB),Qinzhou-Hangzhou Metallogenic Belt(QHMB),Nanling Metallogenic Belt(NLMB),and Wuyi Metallogenic Belt(WYMB).The major mineralization in the four metallogenic belts is granite-related Cu–Au–Mo and porphyrite Fe-apatite,porphyry Cu(Au),and epithermal Pb–Zn–Ag,hydrothermal Cu–Au–Pb–Zn–Ag,and granite-related skarn-type and quartz-veins W–Sn,***-temperature thermochronology,including fissiontrack and U-Th/He dating,has been widely used to constrain tectonic thermal evolution and ore deposits *** fission-track annealing and He diffusion kinetics in accessory minerals,such as zircon and apatite,is essential for dating and *** this study,previous zircon fission-track(ZFT)and apatite fission-track(AFT)ages in South China were *** result shows that the ZFT ages are mainly concentrated at140–90 Ma,and the AFT ages are mainly distributed at70–40 *** age distribution and inversion temperature–time paths reveal heterogeneous exhumation histories in South *** MLYB experienced Late CretaceousCenozoic extremely slow exhumation after rapid cooling in the Early *** northern QHMB(*** southern Anhui province to the Hangzhou Bay)had a relatively faster rate of uplifting and denudation than the southern QHMB in the ***,the northern QHMB rapidly exhumed,while the continuously slow exhumation operated the southern QHMB in the *** southern NLMB had a more rapid cooling rate than the northern NLMB during the Cretaceous time,and the whole NLMB experienced rapid cooling in the Cenozoic,except that the southern Hunan province had the most rapid cooling *** WYMB possibly had experienced slow exhumation since the Late *** exhumation thickness of the four metallogenic belts since90 Ma is approximately calculated as follows:the MLYB≤3.5 km,the northern QHMB concentrated at

关键词： Low-temperature thermochronology Fissiontrack annealing and He diffusion kinetics South China Exhumation history Deposits preservation

Analysis of a new 5-phase bearingless induction motor

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第8期8卷 1311-1319页

作者： HUANG Jin kang min YANG Jia-qiang School of Electrical Engineering Zhejiang University Hangzhou 310027 China

This paper addresses the bearingless motor with a single set of multiphase windings. The interaction between M and M±1 pole-pair magnetic fields produces radial force. Based on this principle,a bearingless machine is obtained. Conventional bearingless machine has dual windings,levitation windings and torque windings,which produce the two magnetic fields. In the proposed bearingless motor,the two needed magnetic fields are produced by feeding two groups of currents to a single set of multiphase windings. Taking a 5-phase induction motor as example,the inductance matrices,considering air gap eccentricity,are calculated with the modified winding function method. The radial force analytical model is deduced by virtual displacement,and its results are validated by FEA. The mathematical model of the new bearingless machine is set up,and the simulation results verified the feasibility of this novel bearingless motor.

关键词： Air-gap-flux-oriented control Bearingless motor Multiphase Radial force Single set of windings Modified winding function method

Existence and Uniqueness of Solutions for two Classes of Functional Equations Arising in Dynamic Programming

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Acta Mathematicae Applicatae Sinica 2007年第2期23卷 195-208页

作者： Ze-qing Liu Shin min kang Department of Mathematics Liaoning Normal University P.O. Box 200 Dalian 116029 China Department of Mathematics and The Research Institute of Natural Science Gyeongsang National UniversityChinju 660-701 Korea

In this paper we establish the existence, uniqueness and iterative approximation of solutions for two classes of functional equations arising in dynamic programming of multistage decision processes. The results presented here extend, and unify the corresponding results due to Bellman, Bhakta and Choudhury, Bhakta and Mitra, Liu and others.

关键词： Functional equation dynamic programming fixed point successive approximation nonexpansive mapping

Weak and Strong Convergence for Fixed Points of Asymptotically Non-expansive Mappings

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Acta Mathematica Sinica,English Series 2004年第6期20卷 1009-1018页

作者： Ze Qing LIU Shin min kang Department of Mathematics Liaoning Normal University Department of Mathematics and Research Institute of Natural Science Gyeongsang National University

A few weak and strong convergence theorems of the modified three-step iterative sequence with errors and the modified Ishikawa iterative sequence with errors for asymptotically non-expansive mappings in any non-empty closed convex subsets of uniformly convex Banach spaces are established. The results presented in this paper substantially extend the results due to Chang (2001), Osilike and Aniagbosor (2000), Rhoades (1994) and Schu (1991).

关键词： Asymptotically non-expansive mapping Fixed point Modified three-step iterative sequence with errors Modified Ishikawa iterative sequence with errors Uniformly convex Banach space Opial’s condition Weak convergence Strong convergence

APPROXIMATION OF COMMON SOLUTIONS OF VARIATIONAL INEQUALITIES VIA STRICT PSEUDOCONTRACTIONS

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Acta Mathematica Scientia 2012年第4期32卷 1607-1618页

作者： Sun Young Cho Shin min kang Department of Mathematics and RINS Gyeongsang National UniversityJinju 660-701 Korea

In this paper, a convex feasibility problem is considered. We construct an iterative method to approximate a common element of the solution set of classical variational inequalities and of the fixed point set of a strict pseudocontraction. Strong convergence theorems for the common element are established in the framework of Hilbert spaces.

关键词： fixed point inverse-strongly monotone mapping nonexpansive mapping variational inequality

Preventive effect of Angelica gigas Nakai extract oral administration on dry eye syndrome

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Asian Pacific Journal of Tropical Medicine 2018年第6期11卷 369-375页

作者： Younje Lee kang min Kim Jae Seon kang Department of Pharmacy Kyungsung UniversityBusanRepublic of Korea Department of Pharmaceutical Science and Technology Kyungsung UniversityBusanRepublic of Korea

Objective:To identify the preventive effect of Angelica gigas Nakai(*** Nakai)extract in a benzalkonium chloride-induced dry eye ***:A total of 28 mice were divided into 4 groups:1)Normal group:mice received only saline;2)positive control group:mice received an oral solution without *** Nakai extract at 10:00 *** 0.2%benzalkonium chloride eye drops at 2:00 p.m.;3)*** Nakai extract(5 mg);4)*** Nakai extract(10 mg).Both group 3)and group 4)received an oral solution with *** Nakai extract(either 5 mg/kg or 10 mg/kg)at 10:00 *** 0.2%benzalkonium chloride eye drops at2:00 *** 14 d of follow-up,tear volume measurement and fluorescein staining were evaluated for the recovery effects on ocular *** analysis was conducted by hematoxylin and eosin *** on ocular epithelium layer was examined using terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling *** of TNF-a was also measured using western blot ***:An increase in both the tear volume and the sustained fluorescein staining scores was observed,demonstrating the preventive effects of *** Nakai *** changes such as irregularity of the epithelial layer and corneal epithelial cell death were inhibited in the *** Nakai extract *** of TNF-αmoderately declined;however,its expression level was still higher,compared to the normal ***:Results from the current study show the significant preventive effect of *** Nakai extract in a mouse model of benzalkonium chloride-induced dry eye ***,*** Nakai extract could be considered as an oral preventive agent for dry eye syndrome in the future.

关键词： Angelica gigas Nakai Benzalkonium chloride Dry eye syndrome

Preparation of SnO Nanosheets and SnO_2 Fine Powders by Hydrazine Method

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稀有金属材料与工程 2006年第A3期35卷 43-46页

作者： kang-min Kim Jong-Heun Lee Department of Materials Science & Engineering Korea UniversitySeoul 136-713Korea

SnO nanosheets and SnO_2 nanopowder were prepared by hydrazine (N_2H_4)-based chemical routes and their gas sensing characteristics were investigated.A SnCl_2-Hydrazine complex (Sn[ N_2H_4)_x]·yH_2O) was formed by a reaction between a SnCl_2 aqueous solution and N_2H_4·H_*** this complex was heat-treated at 450℃,SnO_2 nanopowders were prepared by the decomposition of the *** sensor fabricated from the SnO_2 nano powders showed a good recovery,fast response and high sensitivity for CO 50μg/g (R_a/R_g=1.87),C_2H_5OH 100μg/g (R_a/R_g=4.80),and acetone 100μg/g (R_a/R_g=1.50).SnO nano- sheets could be prepared when a NaOH solution was added to the solution containing the ***_2 nano sheets prepared by the oxidation of SnO nanosheets at 700℃in air atmosphere also showed a good sensitivity R_a/R_g=1.79) for CO 50μg/g at 400℃.The hydrazine method provided an effective tool to controlling the morphology and oxidation state of the tin oxide powders.

关键词： SnO2 SnO hydrazine method gas sensor nanosheets nanopowders

Effect of Microstructures on Elevated-Temperature Wear Resistance of a Hot Working Die Steel

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Journal of Iron and Steel Research International 2011年第10期18卷 47-53页

作者： WEI min-xian WANG Shu-qi WANG Lan CHEN kang-min School of Materials Science and Engineering Jiangsu University Zhenjiang 212013 Jiangsu China

Elevated-temperature wear tests under atmospheric conditions at 400 ℃ were performed for a hot working die steel H21 on a pin-on-disk wear tester. The phase and morphology of worn surfaces were examined using XRD and SEM, and the relation of wear resistance to tempered microstructures was studied for H21 steel. XRD patterns exhibit that oxidative wear is a predominated wear mechanism with Fe3O4 and Fe2O3 on worn surfaces. It is found that with increasing normal load, obvious plastic deformation of substrate appears on worn surfaces. Microstructures start to affect apparently wear resistance of the steel with an increase of load. Under loads of 50--100 N, wear losses of steel retain low values and relatively approach for steels with various microstructures. As loads are increased to 150--200 N, wear losses of steel start to increase obviously and present apparent difference for steel with various microstructures. Wear resistance is found to increase in the sequence as follows., tempered sorbite, tempered martensite, tempered troostite without secondary hardening and tempered troostite with secondary hardening or upcoming one. Higher strength and microstructural stability are required for steels with excellent wear resistance.

关键词： steel heat treatment microstructure wear wear resistance

Stable metal-organic frameworks with high catalytic performance in the cycloaddition of CO_2 with aziridines

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Science China Chemistry 2019年第5期62卷 622-628页

作者： Xiao-min kang Ying Shi Chun-Shuai Cao Bin Zhao College of Chemistry and Key Laboratory of Advanced Energy Material Chemistry Nankai University

Based on the mixed ligands XN(4′-(4-pyridine)4,2′:2′,4′′-terpyridine) and isophthalic acid(IPA), three new metal-organic frameworks(MOFs) {[M_2(XN)_2(IPA)_2]·2 H_2O}_n(M=Co(1), Mn(2), Ni(3)) were assembled and structurally characterized,presenting 3 D pillar-chain feature structures. Stability measurements demonstrate that these compounds possess high thermostability and can endure different organic solvents as well as various acid/base solutions with pH range of 1 to 14. Importantly,compounds 1–3 can serve as high-efficiency catalysts for the transformation of CO_2 and aziridines to form high-value oxazolidinones under mild conditions, exhibiting excellent cyclicity at least five times.

关键词： MOFs stability catalysis oxazolidinones CO2 conversion