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偶氮芳烃铵衍生物的制备及性能(英文)

日用化学品科学 2000年第S2期23卷 63-70页

作者： Ho-Cheol Kang byung min lee Jeongho Yoon minjoong Yoon 韩国化学技术研究所化学工程及应用部国立Chungnam大学化学系

偶氮苯及其衍生物的特点在于可逆顺反异构化。为合成各种光致变色的化合物 ,将环氧乙烷环并入到偶氮苯中 ,设计出易感光中间体。首先 ,制备出一系列的 4-烷基偶氮苯 -4’ -(羟基 -2 -羟丙基三甲基 )甲基硫酸铵 ,并在水溶液中进行研究。... 详细信息

偶氮苯及其衍生物的特点在于可逆顺反异构化。为合成各种光致变色的化合物 ,将环氧乙烷环并入到偶氮苯中 ,设计出易感光中间体。首先 ,制备出一系列的 4-烷基偶氮苯 -4’ -(羟基 -2 -羟丙基三甲基 )甲基硫酸铵 ,并在水溶液中进行研究。在UV光照射下 ,偶氮衍生物的表面活性有重大改变。在光稳定态 ,顺式异构体的量约为 92 %。

关键词：光敏表面活性剂偶氮苯及其衍生物光致变色化合物表面张力光感异构性临界胶束浓度

Densification simulation of compacted Al powders using multi-particle finite element method

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中国有色金属学会会刊：英文版 2009年第B09期19卷 68-75页

作者： Kyung-Hun lee Jung-min lee byung-min KIM School of Mechanical Engineering Pu san National University

The powder compaction simulations were performed to demonstrate deformation behavior of particles and estimate the effect of different punch speeds and particle diameters on the relative density of powder by a multi-particle finite element model(MPFEM). Individual particle discretized with a finite element mesh allows for a full description of the contact mechanics. In order to verify the reliability of compaction simulation by MPFEM, the compaction tests of porous aluminum with average particle size of 20 μm and 3 μm were performed at different ram speeds of 5, 15, 30 and 60 mm/min by MTS servo-hydraulic tester. The results show that the slow ram speed is of great advantage for powder densification in low compaction force due to sufficient particle rearrangement and compaction force increases with decrease in average particle size of aluminum.

关键词：粉末压实粉末粒子多孔铝有限元法模拟致密化平均粒径有限元模型

Effects of elastic-plastic properties of materials on residual indentation impressions in nano-indentation using sharp indenter

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中国有色金属学会会刊：英文版 2012年第S3期22卷 585-595页

作者： Jung-min lee Chan-Joo lee Kyung-Hun lee byung-min KIM Dongnam Regional Division Korea Institute of Industrial Technology Precision Manufacturing Systems Division Pusan National University School of Mechanical Engineering Pusan National University

One of the primary features of nano-indentation technique is that the contact area induced by an indenter is indirectly measured by a relationship between the penetration depth and the known geometry of the ***,this indirect measurement occasionally leads to inaccurate properties of the indented *** objective of this study is to investigate the effects of E/σr and the strain hardening exponents n of materials on the behaviors of pile-up and sink-in in nano-indentation and to predict n values of materials from the residual indentation *** relations between the residual indentation profile and n value of the indented material were identified by dimensional ***,they were numerically formulated using FE analysis of nano-indentation for 140 different combinations of elastic-plastic parameters such as E,σy and *** parameters of hrp/hm,herp/hm,Rr/hm and HO&P/Hreal were introduced as various dimensionless parameters to represent and quantify the residual indentation profile after *** were subsequently characterized as dimensionless functions using n and E/σr ***,the validity of these functions was verified through 3D FE analysis of nano-indentation for Al 6061-T6 and AISI 1010 materials.

关键词： nano-indentation pile-up sink-in strain hardening exponent FE simulation

Deformation prediction of porcelain-enameled steels with strain history by press forming and high-temperature behavior of coating layer

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中国有色金属学会会刊：英文版 2012年第S3期22卷 838-844页

作者： Young-Ki SON Chan-Joo lee Jung-min lee byung-min KIM School of Mechanical Engineering Pusan National University Dongnam Regional Division Korea Institute of Industrial Technology

Porcelain enamel coatings were widely applied for the protection of steel products because they offered high corrosion protection,resistance to heat and abrasion,high hardness,hygiene and ease of *** typical process to produce enameled steels is roughly divided into two stages:the first stage consists of a forming process to give the desired shape to a steel substrate,and the second stage consists of a firing process to bond enamel frits on the *** firing process requires a high temperature above 800 °C,which may lead to austenitic transformation and severe thermal deformation of the steel *** aim of this study is to develop a finite element analysis (FE analysis) technique to predict the mechanical and thermal deformations of the enameled steels during forming and any further enameling process,including *** FE analysis involves analyzing the strain history of the steel substrate,which comprises the stress and thickness distributions of the substrate and its deformed shape,and the high-temperature behavior of the enamel coating *** validity of the FE analysis is verified through the U-bending test and firing test with various numbers and positions of enamel coating layers on the *** results reveal that the FE analysis results agree well with the experimental results with 8% error.

关键词： porcelain enamel firing process finite element analysis enameled steel thermal deformation

FEA technique of hot plate forming process using cell-typed die with cooling device

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中国有色金属学会会刊：英文版 2012年第S3期22卷 831-837页

作者： Jung-min lee In-Kyu lee Kyung-Hun lee Dae-Soon KIM byung-min KIM Dongnam Regional Division Korea Institute of Industrial Technology School of Mechanical Engineering Pusan National University Industrial Technology Division Hyundai Heavy Industries

Hot plate forming using a cell-typed die is a process for forming a large thick plate with a spherical shape for the manufacture of a large spherical LNG ***-typed upper and lower dies made of a framework of steel plates fitted to make a grid pattern are used in this process,and an air-cooling device is separately installed inside the lower die.A finite element analysis (FEA) technique was developed,which included hot forming,air flow,cooling and thermal deformation analysis for the hot plate forming process using the cell-typed ***,the convective and interface heat transfer coefficients were used to reproduce analytically the effects of the cooling device in the hot plate forming analysis.A small-scale model test of the process was conducted to verify the FEA *** analysis results show that the curvature of the final plate agrees well with that of the designed experiment within a maximum relative error of 0.03% at the corner of the plate.

关键词： cell-typed die hot plate forming spherical LNG tank heat transfer coefficient

QKD system with fast active optical path length compensation

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Science China(Physics,Mechanics & Astronomy) 2017年第6期60卷 1-7页

作者： byung Kwon Park min Soo lee min Ki Woo Yong-Su Kim Sang-Wook Han Sung Moon Center for Quantum Information Korea Institute of Science and Technology Department of Nano-materials Science and Engineering Korea University of Science and Technology

We develop a quantum key distribution (QKD) system with fast active optical path length compensation. A rapid and reliable active optical path length compensation scheme is proposed and applied to a plug-and-play QKD system. The system monitors changes in key rates and controls it is own operation automatically. The system achieves its optimal performance within three seconds of operation, which includes a sifted key rate of 5.5 kbps and a quantum bit error rate of less than 2% after an abrupt temperature variation along the 25 km quantum channel. The system also operates well over a 24 h period while completing more than 60 active optical path length compensations.

关键词： quantum key distribution optical path length compensation plug and play field programmable gate array

Antistatic coating material consisting of poly (butylacrylate-co-styrene) core-nickel shell particle

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中国有色金属学会会刊：英文版 2009年第B09期19卷 119-123页

作者： min-Yeong JEONG byung-Yoon AHN Sang-Koul lee Won-Ki lee Nam-Ju JO Department of Polymer Science and Engineering Pusan National University Kumho Petrochemical Samsung Corning Precision Glass Division of Chemical Engineering Pukyong National University

A transparent and antistatic coating material consisting of polymer core-metal shell particle was prepared. As a polymer core, poly(butylacrylate-co-styrene)s ([P(BA-co-sty)s]) with various compositions of butylacrylate and styrene were synthesized by emulsion polymerization. And the effect of comonomer composition on the thermal property of polymer core particle was investigated. By electroless plating method, the nickel particles were formed and deposited on the surface of P(BA-co-Sty) particles to form P(BA-co-Sty) core-nickel shell composite particles. SEM observation confirms that the nickel particles with size of 15 nm are distributed on the surface of the polymer core particles. The surface resistance of P(BA-co-Sty) core-nickel shell composite is 0.8×108Ω/cm2, enough to act as antistatic coating material.

关键词：复合粒子涂层材料单体组成抗静电苯乙烯丁酯聚合物颗粒镍

Electrical Stimulation of Auricular Acupressure for Dry Eye:A Randomized Controlled-Clinical Trial

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Chinese Journal of Integrative Medicine 2017年第11期23卷 822-828页

作者： Jong Soo lee Sang Ho Hwang byung Cheul Shin Young min Park Department of Ophthalmology School of MedicinePusanNational University and Medical Research InstitutePusan National University HospitalPusan(602-739)Republic of Korea Department of Ophthalmology Jung's Eye CenterPusan(616-849)Republic of Korea Division of Clinical Medicine School of Korean MedicinePusan National UniversityYangsan(626-870)Republic of Korea Department of Ophthalmology Gyeongsang National University School of MedicineGyeongsang National University Changwon HospitalChangwon(51472)Republic of Korea

Objective： To evaluate the clinical efficacy of electrical stimulation（ES） of auricular acupressure on reducing the ocular symptoms and signs before and after treatment for dry eye. Methods： The inclusion criteria were the tear film break-up time（TFBUT） below 5 s and a Schirmer test-Ⅰ below 5 mm in dry eyes with ocular symptoms for at least 6 months. Subjects were randomized into a treatment group（50 cases） with continuous low frequency ES under auricular acupressure at acupoints and a no ES under auricular acupressure（no-ES, control group, 50 cases） on the same acupoints. Auricular acupressure were stimulated with ES at 4 master points of both ears, which were performed twice a week for 4 weeks at each point for 30 s. The ocular symptoms, the TFBUT, and Schirmer test-Ⅰ were evaluated before and after this procedure. Results： There were significantly better scores in TFBUT（P=0.032）, the Schirmer test-Ⅰ（P=0.044） and ocular symptoms（P=0.029） at 3 months post-treatment in the treatment group than in the control group. The total effective rate in the treatment group was accomplished in 41（82%） of the 50 cases of dry eye. Conclusions： Auricular acupressure with ES at auricular acupoint improves ocular symptoms and signs of dry eye for a period of at least 3 months.

关键词： auricular acupressure dry eye syndromes electrical stimulation tears

Endoscopic treatment for early gastric cancer

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World Journal of Gastroenterology 2014年第16期20卷 4566-4573页

作者： Yang Won min byung-Hoon min Jun Haeng lee Jae J. Kim Department of Medicine Samsung Medical CenterSungkyunkwan University School of MedicineSeoul 135-710South Korea

Gastric cancer remains one of the most common causes of cancer *** the proportion of early gastric cancer(EGC)at diagnosis is *** treatment for EGC is actively performed worldwide in cases meeting specific *** mucosal resection can treat EGC with comparable results to surgery for selected *** submucosal dissection(ESD)increases the en bloc and complete resection rates and reduces the local recurrence *** has been performed with expanded indication and is expected to be more widely used in the treatment of EGC through the technological advances in the near *** review will describe the techniques,indications and outcomes of endoscopic treatment for EGC.

关键词： Early gastric cancer Endoscopic mucosal resection Endoscopic submucosal dissection