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Advances in Materials Physics and Chemistry 2013年第6期3卷 281-288页

作者： yuri f. migal Vladimir I. Kolesnikov Maria A. Savenkova Daria N. Solodovnikova Rostov State Transport University Rostov-on-Don Russia Scientif.c Centre of.Russian Academy of.Sciences Rostov-on-Don Russia

Сondensed phosphates of.metaphosphatic structure with the equal relation of.metal oxide and phosphorus pentoxide are promising inorganic oleophilic antif.ictional, antiwear and anti-seize, heat-resistant and eco-f.iendly additives to greases. We study in detail one group of.these compounds, phosphorowolf.amates of.alkaline metals MIPWO6 (MI = Li, Na, K, Rb, Cs), by using the ADf.sof.ware package based on the Df. approach. Three stages of.interaction of.molecules of.these substances with an iron surf.ce are investigated: change of.the shape of.molecules near a surf.ce, f.rmation of.the adsorptive complex and its disintegration. It is shown that a strong covalent binding between molecules of.phosphorowolf.amates and a surf.ce appears in the course of.adsorption. High strength of.this binding and also low inner strength of.the chain and its f.exibility provide ef.ective protection of.iron surf.ce against wear. It is also f.und that at adsorption of.phosphorowolf.amates on an iron surf.ce, there is a change of.local structure of.the surf.ce.

关键词： Phosphorowolf.amates of Alkaline Metals Quantum-Chemical Analysis Adsorptive Complex Wear Resistance

Interaction of.Atoms with Grain Surf.ces in Steel: Periodic Dependence of.Binding Energy on Atomic Number and Inf.uence on Wear Resistance

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Advances in Materials Physics and Chemistry 2012年第4期2卷 201-207页

作者： yuri f. migal Vladimir I. Kolesnikov Vladimir N. Doronkin Evgeni S. Novikov Rostov State Transport University Rostov-on-Don Russia Southern Scientif.c Centre of.Russian Academy of.Sciences Rostov-on-Don Russia

Quantum-chemical calculations of.polyatomic clusters simulating a boundary between grains in a surf.ce layer of.steel were carried out. Along with iron atoms the clusters contain atoms of.alloying and impurity elements which appear on the boundary due to grain boundary segregation or intergrain dif.usion. The inf.uence of.the chemical composition of.a segregate on the strength of.coupling between grains and, eventually, on steel wear resistance is analyzed. Results obtained show that the degree of.the strength of.binding of.segregated atoms with atoms of.iron in a metal surf.ce layer is an essential f.ctor inf.uencing wear resistance. It is f.und that the dependence of.energy of.binding of.atoms of.dif.erent elements with grain surf.ce on the atomic number complies with the periodic law. This f.ct can be considered as a theoretical base f.r the prognostication of.strength properties of.steel with dif.erent composition of.alloying and impurity elements. Potential energy curves corresponding to the movement of.atoms on iron surf.ce are studied. They can be usef.l f.r design of.the composition of.multi-layer coats on steel.

关键词： Steel Grain Boundary Compatibility of Elements Wear Resistance Df.

One-Variable Attack on the Industrial f.ult Classif.cation System and Its Def.nse

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Engineering 2022年第12期19卷 240-251页

作者： Yue Zhuo yuri A.W.Shardt Zhiqiang Ge State Key Laboratory of.Industrial Control Technology College of Control Science and EngineeringZhejiang UniversityHangzhou 310027China Department of.Automation Engineering Technische Universität IlmenauIlmenau D-98684Germany

Recently developed f.ult classif.cation methods f.r industrial processes are mainly ***,models based on deep neural networks have signif.cantly improved f.ult classif.cation accuracy owing to the inclusion of.a large number of.data ***,these data-driven models are vulnerable to adversarial attacks;thus,small perturbations on the samples can cause the models to provide incorrect f.ult *** recent studies have demonstrated the vulnerability of.machine learning methods and the existence of.adversarial *** paper proposes a black-box attack method with an extreme constraint f.r a saf.-critical industrial f.ult classif.cation system:Only one variable can be perturbed to craf. adversarial ***,to hide the adversarial samples in the visualization space,a Jacobian matrix is used to guide the perturbed variable selection,making the adversarial samples in the dimensional reduction space invisible to the human *** the one-variable attack(OVA)method,we explore the vulnerability of.industrial variables and f.ult types,which can help understand the geometric characteristics of.f.ult classif.cation *** on the attack method,a corresponding adversarial training def.nse method is also proposed,which ef.iciently def.nds against an OVA and improves the prediction accuracy of.the *** experiments,the proposed method was tested on two datasets f.om the Tennessee–Eastman process(TEP)and steel plates(SP).We explore the vulnerability and correlation within variables and f.ults and verif. the ef.ectiveness of.OVAs and def.nses f.r various classif.ers and *** industrial f.ult classif.cation systems,the attack success rate of.our method is close to(on TEP)or even higher than(on SP)the current most ef.ective f.rst-order white-box attack method,which requires perturbation of.all variables.

关键词： Adversarial samples Black-box attack Industrial data security f.ult classif.cation system

cell2mol:encoding chemistry to interpret crystallographic data

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npj Computational Materials 2022年第1期8卷 1787-1794页

作者： Sergi Vela Ruben Laplaza yuri Cho Clémence Corminboeuf Laboratory f.r Computational Molecular Design(LCMD) Institute of Chemical Sciences and Engineering(ISIC)École Polytechnique Fédérale de Lausanne(EPFL)CH-1015LausanneSwitzerland National Centre f.r Computational Design and Discovery of.Novel Materials(NCCR MARVEL) Ecole Polytechnique Fédérale de Lausanne1015LausanneSwitzerland National Centre f.r Competence in Research“Sustainable chemical processes through catalysis(NCCR Catalysis)” École Polytechnique Fédérale de Lausanne1015LausanneSwitzerland

The creation and maintenance of.crystallographic data repositories is one of.the greatest data-related achievements in *** such as the Cambridge Structural Database host what is likely the most diverse collection of.synthesizable *** properly mined,they could be the basis f.r the large-scale exploration of.new regions of.the chemical space using quantum chemistry(QC).Yet,it is currently challenging to retrieve all the necessary inf.rmation f.r QC codes based exclusively on the available structural data,especially f.r transition metal *** overcome this limitation,we present cell2mol,a sof.ware that interprets crystallographic data and retrieves the connectivity and total charge of.molecules,including the oxidation state(OS)of.metal *** demonstrate that cell2mol outperf.rms other popular methods at assigning the metal OS,while of.ering a comprehensive interpretation of.the unit *** code is made available,as well as reliable QC-ready databases totaling 31k transition metal complexes and 13k ligands that contain incomparable chemical diversity.

关键词： of.ering overcome properly

Mechanisms of.autophagy activation in endothelial cell and their targeting during normothermic machine liver perf.sion

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World Journal of.Gastroenterology 2017年第48期23卷 8443-8451页

作者： yuri L Boteon Richard Laing Hynek Mergental Gary M Reynolds Darius f.Mirza Simon C Af.ord Ricky H Bhogal The Liver Unit University Hospitals of BirminghamMindelsohn Way The Centre f.r Liver Research Institute for Biomedical ResearchUniversity of Birmingham

Ischaemia-reperf.sion injury(IRI) is the leading cause of.injury seen in the liver f.llowing transplantation. IRI also causes injury f.llowing liver surgery and haemodynamic shock. The f.rst cells within the liver to be injured by IRI are the liver sinusoidal endothelial cells(LSEC). Recent evidence suggests that LSEC coordinate and regulates the livers response to a variety of.injuries. It is becoming increasingly apparent that the cyto-protective cellular process of.autophagy is a key regulator of.IRI. In particular LSEC autophagy may be an essential gatekeeper to the development of.IRI. The recent availability of.liver perf.sion devices has allowed f.r the therapeutic targeting of.autophagy to reduce IRI. In particular normothermic machine liver perf.sion(NMP-L) allow the delivery of.pharmacological agents to donor livers whilst maintaining physiological temperature and hepatic f.ow rates. In this review we summarise the current understanding of.endothelial autophagy and how this may be manipulated during NMP-L to reduce liver IRI.

关键词： Autophagy Liver transplant Ischaemiareperf.sion injury Normothermic machine liver perf.sion

Improved Interf.ce of.Encapsulating Sm-Doped TiO₂ Thin f.lms/RuO₂ Schottky Diodes f.r a Junction Spectropy Measurement

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Optics and Photonics Journal 2022年第10期12卷 215-224页

作者： Mariko Murayama yuri Tamamoto Yingda Qian Asuka Ishizawa Simon Hammersley Iain f. Crowe Shuji Komuro Shuji Komuro Xinwei Zhao Department of.Physics Tokyo University of Science Tokyo Japan Research Institute of.Industrial Technology Toyo University Saitama Japan Photon Science Institute and School of.Electrical and Electronic Engineering University of Manchester Manchester UK

The excitation process of.rare-earth ions in oxide semiconductors f.r optical emission is thought to be related to def.ct levels within the band-gap of.the host material. In order to improve understanding of.the role def.ct levels play in the energy transf.r process, junction spectroscopy techniques can be used to investigate the electrically active emission centres. It has been reported that TiO2 is sensitive to humidity at low temperatures, such as those employed when conducting junction spectroscopy measurements. However, there are not many discussions how to prevent this ef.ect and to improve the quality of.measurements. Af.er optimization of.samples such as f.brication of.f.at surf.ce and encupsulant f.r preventing external ef.ect, temperature dependent-capacitance measurements (C-T) were carried out to characterise shallow traps f.rmed within TiO2 band-gap. TiO2 and Sm-doped TiO2 thin f.lms were deposited on SrTiO3 (100) templates by laser ablaton and rectif.ing Ruthenium Oxide Schottky diodes deposited on the TiO2 surf.ce by laser ablation. A Sm or Sm-related shallow trap was observed in the Arrhenius plot of.TiO2:Sm. In this paper, we show the optimized sample f.brication/preparation process that stabilizes the junction spectroscopy measurements, even in the presence of.humidity and we present initial results obtained on samples using these optimized processing techniques.

关键词： Rare Earth TiO2 Photoluminescence Junction Spectroscopy

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Catalan猜想

国外科技新书评介 2015年第9期 7-8页

作者： yuri f. Bilu 朱尧辰不详中国科学院应用数学研究所

1842年，比利时数学家卡塔朗（***）提出问题，后人称之为卡塔朗猜想：所有两个连续整数中是否只有8（=2^3）和9（=3^2）是两个非零整数的“纯”整数幂？换言之，丢番图方程x^P-y^q=1（p，q〉1）是否只有正整数解（x，y，q）=（3，2，3... 详细信息

1842年，比利时数学家卡塔朗（***）提出问题，后人称之为卡塔朗猜想：所有两个连续整数中是否只有8（=2^3）和9（=3^2）是两个非零整数的“纯”整数幂？换言之，丢番图方程x^P-y^q=1（p，q〉1）是否只有正整数解（x，y，q）=（3，2，3）？这个问题（按肯定形式的提法）就是数论中著名的卡塔朗猜想。

关键词： Catalan猜想丢番图方程提出问题非零整数连续整数正整数解数学家比利时

Optical properties and phase-matching in LiInS2

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Chinese Optics Letters 2003年第4期1卷 237-240页

作者：黄金哲任德明胡孝勇曲彦臣 yuri Andreev Pavel Geiko Anna Shaiduko Sergey Grechin Institute of.Opto-Electronics Harbin Institute of TechnologyHarbin 150001 Institute of.Optical Monitoring SB RAS Tomsk 634055 Russia SRIRL Bauman Moscow State Technical University Moscow 107005 Russia

Investigation results on linear and non-linear optical properties, damage threshold and potential ef.iciencies of.biaxial negative LiInS2 crystal are represented. It shows that the crystal has phase-matching and group-velocity matching in wide spectral range f.r second harmonic, sum- and dif.erence-f.equency generation of.visible, near and middle IR lasers. The possibilities of.designing middle IR optical parametric oscillator (OPO) pumped by Nd:YAG and dye lasers and specially possibility of.f.equency conversion with 3 um range f.mtosecond erbium lasers are given.

关键词： Crystals Optical f.equency conversion Optically pumped lasers

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用于低产额奇特原子核质量测量的新型质谱术

Science Bulletin 2023年第20期68卷 2298-2301页

作者： yuri A.Litvinov 张玉虎 Atom- Quanten-&FundamentalphysikGSI Helmholtzzentrum für Schwerionenforschung GmbHDarmstadt 64291Germany CAS Key Laboratory of.High Precision Nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 101408China

Atomic nuclei are many body systems composed of.quantum particles termed nucleons,which are either positively charged protons or electrically neutral *** nuclear f.rce,which describes interactions between nucleons,is highly *** the microscopic scale,it determines the structure of.nuclei,the limits of.their existence,their excitations,decay probabilities,reaction dynamics,etc.[1].On the macroscopic scale,it decides upon the composition of.compact cosmic objects and governs various processes in stellar environments[2].In spite of.the centurylong perpetual investigations,the comprehension of.the nuclear f.rce is f.r f.om being complete.

关键词：质量测量 neutral excitation

普通球粒陨石Semarkona中球粒的PbP-b法年龄

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地球化学 2006年第1期35卷 13-18页

作者：谢智 yuri AMELIN Geological Survey of.Canada OttawaONCanada

陨石年代学研究中常用定年工具包括短半衰期和长半衰期放射性同位素体系,其中前者可以给出陨石形成的相对年龄,而后者则可以给出绝对形成年龄。在长半衰期体系中,PbP-b法是目前能获得高精度可靠年龄的最有效方法。普通球粒陨石Sem arkon... 详细信息

陨石年代学研究中常用定年工具包括短半衰期和长半衰期放射性同位素体系,其中前者可以给出陨石形成的相对年龄,而后者则可以给出绝对形成年龄。在长半衰期体系中,PbP-b法是目前能获得高精度可靠年龄的最有效方法。普通球粒陨石Sem arkona是最不平衡的LL3.0型陨石,受后期热变质的影响很小,因此其年龄研究对反演陨石起源有重要意义。在本文中,对Sem arkona中球粒用不同的化学浸洗流程,并测定浸洗溶液和残渣中UT-hP-b同位素组成,其中浸洗后的残渣均给出相对较高的206Pb/204Pb比值,表明其中含有较多的放射成因Pb同位素组成,这些残渣构成PbP-b等时线,给出年龄为(4566.9±5.8)M a,M SW D=26,与207Pb/206Pb模式年龄在误差范围内一致。尽管Sem arkona陨石可能经历了后期蚀变的影响,但前人对陨石变质温度的研究结果表明,热变质温度并未足以使球粒中Pb同位素体系重置,因此获得的年龄代表Sem arkona陨石球粒的形成年龄。

关键词： Semarkona陨石球粒 Pb-Pb方法