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Forging strength-ductility unity in a high entropy steel

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journal of Materials science & Technology 2022年第18期113卷 158-165页

作者： s.j.Tsianikas Y.Chen j.jeong s.Zhang Z.Xie school of Mechanical Engineering The University of AdelaideSA 5005Australia Centre for Advanced Thin Film Materials and Devices Faculty of Materials and EnergySouthwest UniversityChongqing 400715China Max-Planck-Institut für Eisenforschung Max-Planck-Straße 1Düsseldorf 40237Germany

Fe_(72.4)Co_(13.9)Cr_(10.4)Mn_(2.7)B_(0.34)high entropy steel was prepared by magnetron *** alloy exhibits a high yield strength of 2.92±0.36 GPa while achieving appreciable plasticity of 13.7±1.9%at the ultimate compressive strength(3.37±0.36 GPa).The distribution of iron and chromium shows an un-usual,characteristic spinodal-like pattern at the nanometer scale,where compositions of Fe and Cr show strong anticorrelation and vary by as much as 20 at.%.The high strength is largely attributable to the compositional modulations,combined with fine grains with body-centered cubic(BCC)crystal structure,as well as grain boundary segregation of interstitial *** impressive plasticity is accommodated by the formation and operation of multiplanar,multicharacter dislocation slips,mediated by coherent in-terfaces,and controlled by shear *** excellent strength-ductility combination is thus enabled by a range of distinctive strengthening mechanisms,rendering the new alloy a potential candidate for safety-critical,load-bearing structural applications.

关键词： Deformation mechanisms Micromechanical testing Compositional fluctuations Body-centered cubic High entropy steel

Effects of some Thiol Chelators on Enzymatic Activities in Blood, Liver and Kidneys ofAcute Arsenic (Ⅲ) Exposed Mice

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Biomedical and Environmental sciences 1998年第1期11卷 38-45页

作者： NEELIMATRIPATHI s.j.sFLORA DivisionofPharmacologyandToxicology DefenceResearchandDevelopmentEstablishmentGwalior－474002India D

The effects of meso 2, 3-dimercaptosuccinic acid (DMsA), sodium 2, 3 dimercaptopropane 1-sulfonate (DMPs) and s-adenosyl L-methionine (sAM) on the enzymatic activities of mice were studied. The mice were given intraperitoneal (i. p. ) injections of these chelating agents (1 mmol/kg) and 3 h later the activity of 8-aminolevulinic acid dehydratase (ALAD) in the blood, and aspartate aminotransferase (AsT), alanine aminotransferase (ALT), γ-glutamyltranspeptidase (γ-GT), alkaline phosphatase (ALP) in the liver and kidney were determined. The activity of blood ALAD was significantly increased by the administration of DMsA and sAM while DMPs had only a moderate effect. The activities of other hepatic enzymes changed little when the mice were treated with these chelating agents, except for a significant reduction in hepatic ALP activlty following DMPs administration. Arsenic (Ⅲ) administration markedly increased the activities of ALT and ALP in the liver and kidneys. The changes in the enzymatic activities by treatment with arsenic were prevented by injection of DMsA,DMPs and sAM, DMsA being the most effective. These results indicate that DMsA, DMPs and sAM were not toxic to the liver or kidneys of mice and that treatment with DMsA is more effective than DMPs or sAM in protecting mice from acute hepatic or renal toxicity caused by arsenic.

关键词： DMsA Effects of some Thiol Chelators on Enzymatic Activities in Blood Exposed Mice Liver and Kidneys ofAcute Arsenic

spin synthesis of monolayer of siO_2 thin films

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journal of semiconductors 2015年第4期36卷 16-25页

作者： s.s.shinde s.Park j.shin Korea Research Institute of standards and science

The highly ordered monolayer of submicron size silica （siO2） particles （235 nm） is developed on p-silicon by using three-step spin-coating in colloidal suspension, which has significant potential in various applications. The influence of three-step spin speeds, spinning time, acceleration time between different steps, concentration of siO2 particles in the solution, solution quantity, and the ambient humidity （relative humidity） on the properties ofmonolayer siO2 are studied in order to achieve a large area monolayer film. A relatively high surface coverage and uniform monolayer film of siO2 particles in the range of 85%-90% are achieved by appropriate control of the preparative parameters. We conclude that this method can be useful in industrial applications, because of the fabrication speed, surface coverage and cost of the process.

关键词： thin films spin synthesis electron microscopy

Metasomatic stages and scapolitization Effects on Chemical Composition of Pasveh Pluton,NW Iran

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journal of Earth science 2011年第5期22卷 619-631页

作者： s A Mazhari s Amini j Ghalamghash F Bea Department of Geology Payame Noor University Department of Geology Tarbiat Moallem University Geological survey of Iran Department of Mineralogy and Petrology Fuentenueva CampusUniversity of Granada

Pasveh gabbros are mafic component of a plutonic complex in the northwest sanandaj- sirjan Zone. These cumulative rocks are composed of plagioclase and calcic clinopyroxene （Cpx）, which yield unusually high CaO （〉19 wt.%） in whole-rock chemistry. Petrographical and geochemical data suggest that Pasveh gabbros can be divided into two groups： free scapolite and scapolite-bearing gabbros. The second group has higher Na20, K20, and P205 relative to free scapolite ones and is enriched in LIL （large ion lithophile） and HFs （high field strength） elements. Two stages of metasomatism affected the primary composition of mafic rocks. Firstly, high temperature reaction caused to invert primary high Ti clinopyroxene to low Ti cUnopyroxene＋high Ti amphibole. This reaction was extensive and included all gabbroic samples. Hydrothermal fluids involved in this process can be derived from dehydration reactions of country rocks or from other magmas incorporated in the formation of Pasveh complex pluton. The second metasomatic stage relates to scapolitization of limited parts of gabbroic rocks. An external saline fluid, which is composed of major NaCI and minor KCI and P205 components, impacted locally on Pasveh gabbros and formed the second metasomatic stage. Possible sources of Na and Cl are primary evaporites or brines, which were present in the host sediments of the gabbros. The carbonate-free nature of these hydrothermal fluids suggests that hydrothermal fluids responsible for the formation of scapolite in Pasveh gabbros are derived from marine evaporitic parentage.

关键词： Iran sanandaj-sirjan Zone Pasveh pluton gabbro metasomatism high Ti Cpx low Ti Cpx amphibole scapolite.

The Use of an Electron Microchannel as a self-Extracting and Focusing Plasma Cathode Electron Gun

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Plasma science and Technology 2016年第2期18卷 138-142页

作者： s.CORNIsH j.KHACHAN school of Physics The University of Sydney

A new and simple type of electron gun is *** conventional electron guns,which require a heated filament or extractor,accelerator and focusing electrodes,this gun uses the collimated electron microchannels of an inertial electrostatic confinement（IEC） discharge to achieve the same outcome.A cylindrical cathode is placed coaxially within a cylindrical anode to create the *** beams of electrons and fast neutrals emerge along the axis of the cylindrical *** geometry isolates one of the microchannels that emerge in a negatively biased IEC *** internal operating pressure range of the gun is 35-190 m Torr.A small aperture separates the gun from the main vacuum chamber in order to achieve a pressure *** chamber was operated at pressures of 4-12 m *** measured current produced by the gun was 0.1-3 m A（0.2-14 m A corrected measurement） for discharge currents of 1-45 m A and discharge voltages of 0.5-12 k *** collimated electron beam emerges from the aperture into the vacuum *** performance of the gun is unaffected by the pressure differential between the vacuum chamber and the *** allows the aperture to be removed and the chamber pressure to be equal to the gun pressure if required.

关键词： electron beam electron gun plasma gun neutral gun hollow cathode electron beam microchannel IEC inertial electrostatic confinement

Luminescence characteristics of Dy^(3+) doped Gd_2O_3-CaO-siO_2-B_2O_3 scintillating glasses

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journal of Rare Earths 2016年第6期34卷 583-589页

作者： j.Kaewkhao N.Wantana s.Kaewjaeng s.Kothan H.j.Kim Center of Excellence in Glass Technology and Materials science (CEGM) Nakhon Pathom Rajabhat University Department of Radiologic Technology Faculty of Associated Medical Sciences Chiang Mai University Department of Physics Kyungpook National University

Glasses were prepared from the compositions of 25Gd_2O_3-10 CaO-10 siO_2-（55–x）B_2O_3-xDy_2O_3（where x is 0.0 mol.%–1.0 mol.%） by the conventional melt-quenching technique at 1400 oC. The results demonstrated the increase in the glass density with respect to the increase in the doping concentrations of Dy_2O_3. Nine absorption bands were observed. The emission spectra of the developed glass showed two strong peaks at 577 nm（~4F_（9/2）→~6H_（13/2）） and 482 nm（~4F_（9/2）→~6H_（15/2））. The highest emission intensity was observed from the developed glass prepared at 0.4 mol.% of Dy_2O_3, as the efficient energy transfer took place from Gd^（3＋） to Dy^（3＋）. From the X-ray induced optical luminescence, the emission spectra were identical to those from PL measurements, but with the highest intensity observed from the glass quenched at 0.45 mol.% of Dy_2O_3. Finally, the integral scintillation efficiency of the developed glass was determined at 27% of that of the commercially available BGO crystal.

关键词： amorphous materials glasses oxides optical properties luminescence rare earths

Micro-synchrophasor based special protection scheme for distribution system automation in a smart city

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Protection and Control of Modern Power systems 2020年第1期5卷 97-110页

作者： Deepa s.Kumar savier j.s Biju s.s Dept of Electrical Engineering College of EngineeringTrivandrumKeralaIndia 400/220kV substation Powergrid Corporation of India Ltd.TrivandrumKeralaIndia Power system Operations Kerala State Electricity Board Ltd.KeralaIndia

Introduction:Aspects of power system protection which contributes to mal-operations and blackouts can be improved by supervision of system behavior and response based analysis rather than condition-based or event-based analysis using wide area measurements based on synchrophasor *** paper explores the application of micro-Phasor Measurement Unit for time synchronized real-time distribution network monitoring and agile decision support schemes for system prognosis and *** description:The scheme is proposed as part of a project on“Power system Voltage stability Analysis using synchrophasors in Distribution system of Kerala Grid”at Kerala state Electricity Board *** actual grid occurrence during the severe tropical cyclone Ockhi,is considered as the base case which motivated the *** and evaluation:A voltage stability index(VsI)based special protection scheme(sPs)for radial distribution network at a proposed smart city is presented in the present *** proposed special protection scheme on actual implementation can use data from proposed local micro-Phasor Measurement *** PMU is proposed to be placed at one of the key nodes of the distribution system network in the ***:The VsI is derived using local phasor values and is used to initiate a special Protection scheme for N-1 contingency at the key node,so as to ensure availability of the most essential feeder which provides supply to a hospital campus housing several health institutes of prime *** voltage stability index derived is tested and sPs is validated using real-time grid data.

关键词： Micro-phasor measurement unit Power system protection Voltage stability Power system stability Power distribution smart grids

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永定河三家店以上流域径流减少归因分析

水利水运工程学报 2022年第1期2022卷 67-76页

作者：彭弢贾仰文牛存稳刘欢 khu soon-Thiam 中国水利水电科学研究院流域水循环模拟与调控国家重点实验室北京100038 天津大学环境科学与工程学院天津300350

20世纪70年代以来,永定河流域径流特征发生了巨大变化,下游常年处于断流状态。根据1956—1991年及2006—2018年永定河三家店以上流域各站的气象与水文数据,利用M-K检验和小波分析方法分析了永定河流域的气象要素及径流变化趋势,利用双... 详细信息

20世纪70年代以来,永定河流域径流特征发生了巨大变化,下游常年处于断流状态。根据1956—1991年及2006—2018年永定河三家店以上流域各站的气象与水文数据,利用M-K检验和小波分析方法分析了永定河流域的气象要素及径流变化趋势,利用双累积曲线和基于Budyko假设的弹性系数法进行了径流减少归因分析。结果表明:①1956—2018年间永定河流域的降雨无明显增加或减少趋势,气温有显著上升趋势,蒸发能力略有下降,径流减少非常明显,达到99.9%置信水平。②永定河流域大部分站点的降雨和径流变化存在大概11或23 a的波动周期。③永定河10个水文站的降雨-径流双累积曲线均发生了2~4次较为明显的偏移,在20世纪的60年代中期、70年代初期、80年中期和90年代初期都发生了偏向径流的偏移,这表明在降雨量水平未发生明显变化的情况下,径流减少了。④永定河流域是强人类活动区域,弹性系数绝对值依次为:降水>下垫面参数>蒸发能力,人类活动对径流减少的平均贡献率约为95%。

关键词：永定河流域气候变化趋势分析径流变化归因分析

Environmental impact of radionuclide migration in groundwater from a low intermediate level radioactive waste repository

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journal of Environmental sciences 2001年第2期13卷 180-184页

作者： j s Wang Z F Yang s s Li Z M Wang Institute of Environmental sciences Beijing Normal University State Key Joint Laboratory of Environmental Simulation and Pollution Control Beijing 100875 China.

The radionuclide migration from a certain Chinese repository with low-intermediate level radioactive solid waste is studied. The migration in groundwater is analyzed and computed in detail. Under presumption of normal releasing, or the bottom of the repository has been marinated for one month with precipitation reaching 600 mm once and a 6 m aerated zone exists, a prediction for 7 radionuclides is conducted. It shows that the aerated zone is the primary barrier for migration. The migration for radionuclides 60Co, 137Cs, 90sr, 63Ni, etc. will be retarded in it within 500 years. The concentration of 239Pu will be decreased by amount of 6 order. Only 3H and 14C can migrate through the aerated zone. The radionuclides that go through the aerated zone and enter the aquifer will exist in spring, stream and sea. Based on this, the intake dose by residents in different age group resulting from drinking contaminated spring water, eating seafood is calculated. The results showed that the impact of the repository to the key resident group is lower than the limit in national repository regulation standard. This complies with the repository management target.

关键词： intermediate level radioactive waste repository Environmental impact of radionuclide migration in groundwater from a low