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类风湿关节炎肺间质病变:寻常型间质性肺炎的放射学研究

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国际医学放射学杂志 2014年第2期 179-179页

作者： D.Assayag b.M.Elicker T.h.Urbania T.V.Colby b.h.kang J.h.Ryu 张印 Department of Laboratory Medicine and Pathology Mayo Clinic PhoenixAriz

目的探讨CT甄别类风湿关节炎肺间质病变(RA-ILD)中寻常型间质性肺炎(UIP)病理组织学特征的准确性。材料与方法本研究获得机构审查委员会批准,所有病

关键词：类风湿关节炎类风湿性关节炎间质性肺炎间质病变寻常型放射学

Numerical simulation on borehole breakout and borehole size effect using discrete element method

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International Journal of Mining Science and Technology 2020年第5期30卷 623-633页

作者： h.Lin W.h.kang J.Oh I.Canbulat b.hebblewhite School of Minerals and Energy Resources Engineering University of New South WalesSydneyNSW 2052Australia Centre for Infrastructure Engineering Western Sydney UniversityPenrithNSW 2751Australia

Estimation of horizontal stress magnitudes from borehole breakouts has been an attractive topic in the petroleum and mining industries,although there are critical research gaps that remain *** this paper,numerical simulation is conducted on Gosford sandstone to investigate the borehole breakout and its associated borehole size effect,including temperature *** discrete element method(DEM)model shows that the borehole breakout angular span is constant after the initial formation,whereas its depth propagates along the minimum horizontal stress *** indicates that the breakout angular span is a reliable parameter for horizontal stress *** borehole size effect simulations illustrated the importance of borehole size on breakout geometries in which smaller borehole size leads to higher breakout initiation stress as well as the stress re-distribution from borehole wall outwards through *** implies that the stress may be averaged over a distance around the borehole and breakout initiation occurs at the borehole wall rather than some distance into the *** addition,the numerical simulation incorporated the thermal effect which is widely encountered in deep geothermal *** on the results,the higher temperature led to lower breakout initiation stress with same borehole size,and more proportion of shear cracks was generated under higher *** indicates that the temperature might contribute to the micro-fracturing mode and hence influences the horizontal stress estimation results from borehole breakout *** simulation showed that breakout shape and dimensions changed considerably under high stress and high temperature conditions,suggesting that the temperature may need to be considered for breakout stress analysis in deep locations.

关键词： borehole breakout breakout angular span borehole size effect Numerical simulation Thermal effect

EFFECT OF COLD WORKING ON ThE AGING PROPERTIES OF Cu-Cr-Zr-Mg ALLOY bY ARTIFICIAL NEURAL NETWORK

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Acta Metallurgica Sinica(English Letters) 2004年第5期17卷 741-746页

作者： J.h.Su h.J.Li Q.M.Dong P.Liu b.X.kang b.h.Tian CollegeofMaterialsScienceandEngineering NorthwesternPolytechnicalUniversityXi＇an710072China GollegeofMaterialsScienceandEngineering HenanUniversityofScienceandTechnologyLuoyang471003China

A developmental research has been carried out to deal with the high performance of Cu-Cr-Zr-Mg lead frame alloy by artificial neural network (ANN). Using the cold working to assist in the aging hardening can improve the the hardness and electrical conductivity properties of Cu-Cr-Zr-Mg lead frame alloy. This paper studies the effect of different extent of cold working on the aging properties by a supervised ANN to model the non-linear relationship between processing parameters and the properties. The back-propagation (bP) training algorithm is improved by Levenberg-Marquardt algorithm. A basic repository on the domain knowledge of cold worked aging processes is established via sufficient data mining by the network. The predicted values of the ANN coincide well with the tested data. So an important foundation has been laid for prediction and optimum controlling the rolling and aging properties of Cu-Cr-Zr-Mg alloy.

关键词： Cu-Cr-Zr-Mg alloy cold working aging artificial neural network (ANN)

Effects of Weaving Laser on Weld Microstructure and Crack for Al 6k21-T4 Alloy

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Journal of Materials Science & Technology 2011年第1期27卷 93-96页

作者： b.h.Kim N.h.kang W.T.Oh C.h.Kim J.h.Kim Y.S.Kim Y.h.Park Department of Materials Science and Engineering Pusan National UniversitySan30Jangjeon-dongGeumjeong-guBusan 609-735Korea Department of Materials and Components Engineering Dong-Eui UniversityBusan 614-714Korea Advanced Joining Technology Team KITECH7-47Songdo-dongYeonsu-guIncheon 406-840Korea Division for Dongnam Area Technology Service KITECHJisa-dongGanseo-guBusan 618-230Korea

For Al 6k21-T4 overlap weld joint,the shear-tensile strength by using the weaving laser was improved as compared to the case of linear *** the specimen of low strength,the porosity was distributed continuously along the intersection between the plates and fusion ***,for the optimized welding condition,large oval-shaped porosities were located only in the advancing track of the concave ***,the continuity of cracks and porosities played a key role to determine the ***,the weaving width was also the important parameter to control the ***,the concave part had more significant hot and cold cracking in the weld and heat-affected zone（hAZ）,respectively,than the convex part.

关键词： Weaving laser Weld microstructure Void Al alloy

INTERACTION OF PRECIPITATION AND RECRYSTALLIZATION IN RAPIDLY SOLIDIFIED Cu-Cr-Zr-Mg ALLOY

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Acta Metallurgica Sinica(English Letters) 1999年第3期12卷 273-275,576-277页

作者： Liu, P. kang, b.X. Cao, X.G. huang, J.L. Yin, b. Gu, h.C. Xi'an Jiaotong Univ Xi'an China

The recrystallization process of a rapidly solidified Cu-Cr-Zr-Mg alloy during its aging was investigate experimentally. It was found that (1) upon aging, the precipitation process takes place prior to recrystallization for the cold-deformed Cu-Cr-Zr-Mg alloy produced by rapid solidification, and the precipitates have a restrained effect on the following recrystallization process; (2) the hindrance of the dispersed fine precipitates to the common recrystallization leads to the simultaneous in situ and discontinuous recrystallization; (3) the resolution of the precipitates in the front of migrating grain boundaries takes place during the nucleation and growth of recrystallization, which results in a supersaturation in the recrystallized zones, while the re-precipitation of the supersaturated solute atoms in vacancies further increases the dispersion hardening effect.

关键词： Crystal microstructure Precipitation (chemical) Rapid solidification Recrystallization (metallurgy) Supersaturation

The dissolution properties of 6b-Nitrohexahydro-2h-1,3,5-trioxacyclopenta[cd]-pentalene-2,4,6-triyl trinitrate（NhTPN） in N,N-dimethyl formamide（DMF）

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The dissolution properties of 6b-Nitrohexahydro-2H-1,3,5-tri...

Non-relativistic scattering amplitude for a new multi-parameter exponential-type potential

第十七届全国化学热力学和热分析学术会议

作者： J.Q.Zhang S.Y.kang h.Y.Zhou h.M.Shi R.R.Dou b.Z.Wang R.Z.hu Key Laboratory of Space Applied Physics and Chemistry of Ministry of Education Department of Applied Chemistry School of Science Northwestern Polytechnical University

The enthalpy of dissolution of 6b-Nitrohexahydro-2h-1, 3, 5-trioxacyclopenta[cd]-pentalene-2, 4, 6-triyl trinitrate（NhTPN）（CAS: 1428236-72-9） in N,N-dimethyl formamide（DMF） was measured by means of a DC08 Calvet microcalorimeter at 298.15 K. Empirical formulae for the calculation of the enthalpy of dissolution, relative partial molar enthalpy, and relative apparent molar enthalpy were obtained from the experimental data of the enthalpies of dissolution of NhTPN in DMF. The kinetic equation that describes the dissolution process of NhTPN in DMF at 298.15 K is determined as.

关键词： 6b-Nitrohexahydro-2h-1,3,5-trioxacyclopenta[cd]-pentalene-2,4,6-triyl trinitrate(NhTPN) Calvet microcalorimeter Dissolution Kinetics

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Chinese Physics b 2016年第8期25卷 21-25页

作者： Yazarloo b h Mehraban h hassanabadi h Physics Department Semnan University Physics Department Shahrood University of Technology

In this paper, we study the scattering properties of s-wave Schrdinger equation for the multi-parameter potential,which can be reduced into four special cases for different values of potential parameters, i.e., hulthn, Manning–Rosen,and Eckart potentials. We also obtain and investigate the scattering amplitudes of these special cases. Some numerical results are also obtained and reported.

关键词： scattering amplitude Schrodinger equation multi-parameter potential phase shifts cross section

Experimental and Numerical Investigation on Impact Performance of Carbon Reinforced Aluminum Laminates

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Journal of Materials Science & Technology 2010年第4期26卷 327-332页

作者： S.h. Song Y.S. byun T.W. Ku W.J. Song J. Kim b.S. kang National Core Research Center Pusan National University Busan 609-735 Korea Dept. of Aerospace Engineering Pusan National University Busan 609-735 Korea Industrial Liaison Innovation Cluster Pusan National University Busan 609-735 Korea

It is known that fiber metal laminates （FML） as one of hybrid materials with thin metal sheets and fiber/epoxy layers have the characteristics of the excellent damage tolerance, fatigue and impact properties with a relatively low density. Therefore, the mechanical components using FML can contribute the enhanced safety level of the sound construction toward the whole body. In this study, the impact performance of carbon reinforced aluminum laminates （CARAL） is investigated by experiments and numerical simulations. Drop weight tests are carried out with the weight of 4.7 kg at the speed of 1 and 2 m/s, respectively. Dynamic non-linear transient analyses are also accomplished using a finite element analysis software, AbAQUS. The experiment results and numerical results are compared with impact load-time histories. Also, energy-time histories are applied to investigate the impact performance of CARAL.

关键词： Fiber metal laminates (FML) Carbon reinforced aluminum laminates (CARAL) Numerical simulation Impact performance

Erosion-corrosion and its mitigation on the internal surface of the expansion segment of N80 steel tube

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International Journal of Minerals,Metallurgy and Materials 2021年第1期28卷 98-110页

作者： Tan Shang Xian-kang Zhong Chen-feng Zhang Jun-ying hu bálint Medgyes State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China Department of Electronics Technology Budapest University of Technology and EconomicsBudapest H-1111Hungary

We investigated erosion-corrosion(E-C) and its mitigation on the internal surface of the expansion segment of N80 steel tube in a loop system using array electrode technique, weight-loss measurement, computational-fluid-dynamics simulation, and surface characterization *** results show that high E-C rates can occur at locations where there is a high flow velocity and/or a strong impact from sand particles, which results in different E-C rates at various ***, it can be expected that localized corrosion often occurs in such *** E-C rate at each location in the expansion segment can be significantly mitigated with an imidazoline derivative inhibitor, as the resulting inhibitor layer significantly impedes the electrochemical reaction ***, we found that this inhibitor layer could not effectively reduce the difference in the erosion rates at different locations on the internal surface of the expansion *** means that localized corrosion can still occur at the expansion segment despite the presence of the inhibitor.

关键词： erosion-corrosion expansion segment array electrode technique inhibitor localized corrosion