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Transactions of Nonferrous Metals Society of China 2024年第6期34卷 1965-1975页

作者： Kolela j NYEMBWE Elvis FOSSO-KANKEU frans WAANDERS Martin MKANDAWIRE Didier K NYEMBWE Bhekie B MAMBA Water Pollution Monitoring and Remediation Initiatives Research Group School of Chemical and Minerals EngineeringFaculty of EngineeringNorth-West UniversityPotchefstroomSouth Africa Department of Mining Engineering College of Science Engineering and TechnologyUniversity of South AfricaFlorida Science CampusJohannesburgSouth Africa Department of Metallurgy Faculty of Engineering and Built EnvironmentUniversity of JohannesburgDoornfonteinJohannesburgSouth Africa Department of Chemistry School of Science and TechnologyCape Breton UniversityCanada School of Mining Metallurgy and Chemical EngineeringFaculty of Engineering and the Built EnvironmentUniversity of JohannesburgJohannesburgSouth Africa Institute for Nanotechnology and Water Sustainability College of Science Engineering and TechnologyUniversity of South AfricaFlorida Science CampusJohannesburgSouth Africa

由于钝化层的形成,黄铜矿(CuFeS_(2))在氧化条件下浸出通常具有溶解速率缓慢的特点。为了将黄铜矿浸出过程中的钝化效应降至最低并提高铜的回收率,研究了CuFeS_(2)在不同ph值(1.0、1.5和1.8)和温度(25和50℃)条件下浸出时,向Fe_(2)(SO_(... 详细信息

由于钝化层的形成,黄铜矿(CuFeS_(2))在氧化条件下浸出通常具有溶解速率缓慢的特点。为了将黄铜矿浸出过程中的钝化效应降至最低并提高铜的回收率,研究了CuFeS_(2)在不同ph值(1.0、1.5和1.8)和温度(25和50℃)条件下浸出时,向Fe_(2)(SO_(4))_(3)−h_(2)SO_(4)浸出剂中添加磁铁矿(Fe_(3)O_(4))对铜溶解速率的影响。结果表明,溶液ph值、电位和温度在溶解过程中起着关键作用。在ph 1.8、50℃和400 mV的条件下,Fe_(3)O_(4)−CuFeS_(2)混合体系中铜的回收率达到最大值(70%),而未添加Fe_(3)O_(4)时,CuFeS_(2)中铜的回收率较低(48%)。添加Fe_(3)O_(4)有助于维持较高的氧化还原值。添加Fe_(3)O_(4)还使活化能从79.04 kj/mol降低到53.69 kj/mol。这表明,当Fe_(3)O_(4)存在时,由于形成了更易溶解的中间体斑铜矿(Cu_(5)FeS_(4))和辉铜矿(Cu_(2)S),CuFeS_(2)更易被氧化。两种溶解过程都受到矿物表面的化学控制。此外,对浸出残渣的矿物学分析表明,当无Fe_(3)O_(4)存在时,作为表面钝化物的黄钾铁矾浓度较高。因此,添加Fe_(3)O_(4)减少了钝化层的形成,提升了铜的回收率。

关键词：黄铜矿溶解磁铁矿电偶钝化

Nitridation of Ni-based alloys:thermodynamics,kinetics,and deformation phenomena accompanying internal precipitation

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Rare Metals 2006年第5期25卷 501-511页

作者： Alexander A.Kodentsov jorma K.Kivilahti frans j.j.van Loo Laboratory of Materials and Interface Chemistry Eindhoven University of TechnologyP.O.Box 5135600 MBEindhovenThe Netherlands Laboratory of Electronics Production Technology Helsinki University of TechnologyFIN-02150 EspooFinland

When a moderately stable phase is precipitated out during an intemal reaction, the behaviour of the penetrating atoms within the diffusion zone can be interpreted based on thermodynamic considerations. Evidence for “up-hill” diffusion of the penetrating species through the matrix towards the precipitation front during the intemal nitridation of Ni-Cr alloys at 1125℃ and 6000 bar of N2-pressure was predicted. Such behaviour of nitrogen is opposite to the boundary conditions in Wagner＇s description of internal reactions. A volume change associated with the precipitation reaction resulted in a stress gradient between the alloys surface and the intemal nitridation front. Stress relief occurred mainly by transport of nickel to the gas/metal interface. Pipe diffusion-controlled creep is the dominant stress accommodation mechanism during nitriding of dilute Ni-Cr alloys at 700℃ under a flowing Nh3 ＋ h2 gas mixture.

关键词： nitridation nickel alloys thermodynamics diffusion internal precipitation

Long Term Salinity Stress Reveals Variety Specific Differences in Root Oxidative Stress Response

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Rice science 2012年第1期19卷 36-43页

作者： Prasad SENADhEERA Shamala TIRIMANNE frans j M MAAThUIS Department of Botany the Open University of Sri LankaNugegodaSri Lanka Department of Plant Sciences University of ColomboColomboSri Lanka Biology Department Area 9University of YorkYorkYO10 5DDUK

Salinity stress induces oxidative stress caused by reactive oxygen species （ROS）： superoxide radicals, hydrogen peroxide （h2O2） and hydroxyl radicals. Activities of both enzymatic and non-enzymatic components of the antioxidant system and related growth parameters were studied in the roots of the salt tolerant rice variety FL478 and the sensitive variety IR29 in response to long term stress （12 d）induced by 50 mmol/L NaCI. The comparative study showed that FL478 maintained higher relative growth rate and lower Na＋/K＋ in the roots than IR29 due to a higher membrane stability index that effectively exclude Na＋. Lower TBARS （thiobarbituric acid reactive substance） content in FL478 roots indicated that its membrane was relatively unaffected by ROS despite high h2O2 content recorded under the salinity stress. Relatively higher superoxide dismutase activity along with a parallel increase in transcript level of superoxide dismutase （Os07g46990） in FL478 indicated that this protein might make a vital contribution to salt stress tolerance. Although the content of ascorbic acid remained unchanged in FL478, the activity of ascorbic peroxidases （APOXs） was reduced comparably in the both varieties. Transcriptomic data showed that a larger number of peroxidase genes were upregulated in FL478 compared to IR29 and several of which might provide engineering targets to improve rice salt tolerance.

关键词： root membrane stability salinity stress transcriptome superoxide dismutate ascorbic peroxidase rice

Aspirin inhibits cell viability and mTOR downstream signaling in gastroenteropancreatic and bronchopulmonary neuroendocrine tumor cells

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World journal of Gastroenterology 2014年第29期20卷 10038-10049页

作者： Matilde Spampatti George Vlotides Gerald Spttl julian maurer Burkhard Gke Christoph j Auernhammer Department of Internal Medicine Ⅱ University-Hospital Campus GrosshadernInterdisciplinary Center of Neuroendocrine Tumours of the GastroEnteroPancreatic System (GEPNET-KUM)Ludwig-Maximilians-University of Munich U.O.C.Gastroenterologia 2 Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico Università degli Studi di Milano

AIM: To investigate the effect of aspirin on neuroendocrine tumor (NET) cell growth and signaling in vitro.

关键词： Neuroendocrine tumors Aspirin Cell Viability Mammalian target of rapamycin protein

ph-dependent leaching mechanism of carbonatitic chalcopyrite in ferric sulfate solution

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Transactions of Nonferrous Metals Society of China 2021年第7期31卷 2139-2152页

作者： Kolela j NYEMBWE Elvis FOSSO-KANKEU frans WAANDERS Martin MKANDAWIRE Water Pollution Monitoring and Remediation Initiatives Research Group School of Chemical and Minerals EngineeringFaculty of EngineeringNorth-West UniversitySouth Africa Department of Chemistry School of Science and TechnologyCape Breton UniversityCanada

The dissolution of a carbonatitic chalcopyrite(CuFeS2)was studied in h_(2)SO_(4)−Fe_(2)(SO_(4))_(3)−FeSO_(4)−h_(2)O at varying ph values(0.5−2.5)and 25℃ for 12 *** were conducted with a size fraction of 53−75μ*** Cu recoveries,below 15%,were observed in all ph *** results from the XRD,SEM−EDS,and optical microscopic(OM)analyses of the residues indicated that the dissolution proceeded through the formation of transient ***_(3.39)Fe_(0.61)S_(4) and Cu_(2)S were the intermediate phases at ph 0.5 and 1.0,respectively,whereas Cu_(5)FeS_(4) was the major mineral at ph 1.5 and *** thermodynamic modelling predicted the sequential formation of CuFeS_(2)→Cu_(5)FeS_(4)→Cu_(2)S→*** soluble intermediates were Cu_(5)FeS_(4) and Cu2S,whilst,CuS and Cu_(3.39)Fe_(0.61)S_(4) were the refractory phases,supporting their cumulating behaviour throughout the *** obtained results suggest that the formation of CuS and Cu_(3.39)Fe_(0.61)S_(4) could contribute to the passive film formed during CuFeS_(2) leaching.

关键词： chalcopyrite carbonatite chemical leaching leaching mechanism intermediate phase thermodynamic behavior

Mn＋1AXn Phonon Density of States： Ti3AlC2 and Ti3SiC2 Simulation and Experimentation Results

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journal of Chemistry and Chemical Engineering 2015年第4期9卷 253-261页

作者： Veronica Gray Gordon j Kearley Oliver Kirstein Ramzi Kutteh Erich h Kisi Daniel P. Riley frans Trouw School of Engineering University of Newcastle Callaghan NSW 2308 Australia Bragg Institute Australian Nuclear Science & Technology Organisation Lucas Heights NEW 2234 Australia European Spallation Source ESS AB Lund 22100 Sweden School of Physics University of Sydney Sydney NEW2006 Australia Institute of Materials Engineering Australian Nuclear Science & Technology Organisation Lucas Heights NEW2234 Australia Lujan Centre Los Alamos Neutron Science Center Los Alamos National Laboratory Los Alamos NM 87545 USA

For the first time detailed measurements of the DOS （density of states） for Ti3AIC2 and Ti3SiC2 are presented at temperatures between T = 10 and 100 K. For Ti3AIC2 a DFT （density functional theory） simulation of lattice dynamics is compared to experimental data demonstrating a noticeable difference between the spectra especially below 40 meV. In the case of Ti3SiC2 the DFT model is augmented with MD （molecular dynamics） simulations resulting in the measured and simulated spectra resembling one another more closely but still having significant differences below 40 meV. Within the experimental spectra, there are features up to and including 20 meV which are unaccounted for by the simulation. Tracing individual atoms generated by the computer models suggests anharmonic motion of Si within the Ti3SiC2. The results presented could explain differences between calculated elastic moduli using DFT harmonic lattice dynamics simulations and results from recent experiments.

关键词： Anharmonic anisotropic lattice dynamics Mn+1AXn phase ceramics ab initio molecular dynamics.

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骨CT扫描结果的三维重建(评价)

放射学实践 1992年第2期7卷 84-92页

作者： h.P.Carduck R.Vosshenrich.j.maurer A.helwig E.Grabbe 徐霓霓 Abt.Rontgendiagnostik I Kliniken der Georg-August-Universitat GottingenRobert-Koch-StraBe 403400GottingenFRG 北京宜武医院

现今已能对图像进行三维重建,直观显示正常的和病理的骨结构.倘若期待从平面重建得出辅助诊断是不会有什么收获的.但是未来的发展不可估量,所以这期待也是有道理的.

关键词：骨结构 CT

Performance and calibration of quark/gluon-jet taggers using 140 fb^(-1) of pp collisions at √s=13 TeV with the ATLAS detector

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Chinese Physics C 2024年第2期48卷 1-25页

作者： G. Aad B. Abbott K. Abeling N.j. Abicht S.h. Abidi A. Aboulhorma h. Abramowicz h. Abreu Y. Abulaiti B.S. Acharya C. Adam Bourdarios L. Adamczyk S.V. Addepalli M.j. Addison j. Adelman A. Adiguzel T. Adye A.A. Affolder Y. Afik M.N. Agaras j. Agarwala A. Aggarwal C. Agheorghiesei A. Ahmad F. Ahmadov W.S. Ahmed S. Ahuja X. Ai G. Aielli A. Aikot M. Ait Tamlihat B. Aitbenchikh I. Aizenberg M. Akbiyik T.P.A. Åkesson A.V. Akimov D. Akiyama N.N. Akolkar K. Al Khoury G.L. Alberghi j. Albert P. Albicocco G.L. Albouy S. Alderweireldt M. Aleksa I.N. Aleksandrov C. Alexa T. Alexopoulos F. Alfonsi M. Algren M. Alhroob B. Ali h.M.j. Ali S. Ali S.W. Alibocus M. Aliev G. Alimonti W. Alkakhi C. Allaire B.M.M. Allbrooke j.F. Allen C.A. Allendes Flores P.P. Allport A. Aloisio F. Alonso C. Alpigiani M. Alvarez Estevez A. Alvarez Fernandez M. Alves Cardoso M.G. Alviggi M. Aly Y. Amaral Coutinho A. Ambler C. Amelung M. Amerl C.G. Ames D. Amidei S.P. Amor Dos Santos K.R. Amos V. Ananiev C. Anastopoulos T. Andeen j.K. Anders S.Y. Andrean A. Andreazza S. Angelidakis A. Angerami A.V. Anisenkov A. Annovi C. Antel M.T. Anthony E. Antipov M. Antonelli F. Anulli M. Aoki T. Aoki j.A. Aparisi Pozo M.A. Aparo L. Aperio Bella C. Appelt A. Apyan N. Aranzabal S.j. Arbiol Val C. Arcangeletti A.T.h. Arce E. Arena j-F. Arguin S. Argyropoulos j.-h. Arling O. Arnaez h. Arnold G. Artoni h. Asada K. Asai S. Asai N.A. Asbah j. Assahsah K. Assamagan R. Astalos S. Atashi R.j. Atkin M. Atkinson h. Atmani P.A. Atmasiddha K. Augsten S. Auricchio A.D. Auriol V.A. Austrup G. Avolio K. Axiotis G. Azuelos D. Babal h. Bachacou K. Bachas A. Bachiu F. Backman A. Badea P. Bagnaia M. Bahmani A.j. Bailey V.R. Bailey j.T. Baines L. Baines O.K. Baker E. Bakos D. Bakshi Gupta V. Balakrishnan R. Balasubramanian E.M. Baldin P. Balek E. Ballabene F. Balli L.M. Baltes W.K. Balunas j. Balz E. Banas M. Bandieramonte A. Bandyopadhyay S. Bansal L. Barak M. Barakat E.L. Barberio D. Barberis M. Barbero M.Z. Barel K.N. Barends T. Barillari M-S. Barisits T. Barklow P. Baron D.A. Baron Mo The ATLAS Collaboration

The identification of jets originating from quarks and gluons,often referred to as quark/gluon tagging,plays an important role in various analyses performed at the Large hadron Collider,as Standard Model measurements and searches for new particles decaying to quarks often rely on suppressing a large gluon-induced *** paper describes the measurement of the efficiencies of quark/gluon taggers developed within the ATLAS Collaboration,using √s=13 TeV proton–proton collision data with an integrated luminosity of 140 fb^(-1) collected by the ATLAS *** taggers with high performances in rejecting jets from gluon over jets from quarks are studied:one tagger is based on requirements on the number of inner-detector tracks associated with the jet,and the other combines several jet substructure observables using a boosted decision tree.A method is established to determine the quark/gluon fraction in data,by using quark/gluon-enriched subsamples defined by the jet *** in tagging efficiency between data and simulation are provided for jets with transverse momentum between 500 GeV and 2 TeV and for multiple tagger working points.

关键词： ATLAS jET QUARK GLUON TAGGING

CGA136872-一种玉米田选择性芽后新除草剂

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农药译丛 1989年第1期11卷 55-58页

作者： W.maurer h.R.Gerber j.Rufener 张湘宁瑞士Ciba-Geigy 司农业化学研究开发部瑞士Ciba-Geigy公司农业化学研究开发部

CGA 136872是一种新的磺酰脲类化合物。4年来在主要玉米种植区进行的广泛田间试验表明,所有的蜀黍属(Sorghum)杂草对该化合物都具有非常高的敏感性。Ciba-Geigy公司目前正在开发这一品种,用以芽后选择性防除玉米地中的蜀黍属杂草。CGA

关键词：除草剂 CGA136872 玉米田