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Influence of Features of Interphase Boundaries on Mechanical Properties and Fracture Pattern in Metal-Ceramic Composites

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Journal of Materials Science & Technology 2013年第11期29卷 1025-1034页

作者： Sergey Psakhie Vladimir Ovcharenko Baohai yu.evgeny Shilko Sergey Astafurov yu.y Ivanov Alexey Byeli Alexey Mokhovikov Institute of Strength Physics and Materials Science Siberian Branch of the Russian Academy of Sciences Institute of High Technology Physics Tomsk Polytechnic University Shenyang National Laboratory for Materials Science Institute of High Current Electronics Siberian Branch of the Russian Academy of Sciences Physical-Technical Institute yu.ga Technological Institute Tomsk Polytechnic University

The results of a theoretical study on the influence of strength of interphase boundaries in metal-ceramic composite on macroscopical characteristics of composite response such as strength, deformation capacity, fracture energy and fracture pattern are presented. The study was conducted by means of computer-aided simulation by means of movable cellular automaton method taking account of a developed ＂mesoscopical＂ structural model of particle-reinforced composite. The strength of interphase boundaries is found to be a key structural factor determining not only the strength properties of metal-ceramic composite, but also the pattern and rate of fracture. The principles for achievement of the high-strength values of particle/binder interfaces in the metal-ceramic composition due to the formation of the wide transition zones （areas of variable chemical composition） at the interphase boundaries are discussed. Simulation results confirm that such transition zones provide a change in fracture mechanism and make the achievement of a high-strength and a high deformation capacity of metal-ceramic composite possible.

关键词： Metal--ceramic composites Particle-reinforced composite Interphase boundaries Discrete element based analysis Strength and fracture energy Fracture pattern

Acoustic emission characterization of sliding wear under condition of direct and inverse transformations in lowtemperature degradation aged Y-TZP and Y-TZP-Al_2O_3

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Friction 2018年第3期6卷 323-340页

作者： Nikolai L SAVCHENKO Andrey V FILIPPOV Sergei yu.TARASOV Andrey I DMITRIEV evgeny V SHILKO Aleksandr S GRIGORIEV Institute of Strength Physics and Materials Science SB RAS National Research Tomsk Polytechnic University National Research Tomsk State University

In this research, results of the investigation of the sliding friction and wear of yttria-stabilized tetragonal zirconia polycrystalline(Y-TZP) and Y-TZP-Al_2O_3 samples preliminarily subjected to low-temperature degradation are reported. The investigation was carried out using a pin-on-disk tribometer with simultaneous recording of acoustic emission(AE) and vibration acceleration. The sliding wear process was found to be determined by dynamic direct and inverse Y-TZP transformations detected by monoclinic and tetragonal X-ray diffraction peak ratios. The AE signals generated under direct and inverse transformations can be used to characterize wear and friction mechanisms as well as direct and inversed sliding-induced phase transformations. The AE signal energy grows with the friction coefficient and the inverse transformation degree. Reduction of the AE signal energy indicates establishing the mild wear stage caused by effective stress-induced direct martensitic transformation. The AE signal median frequency increases in the case of lower friction. Numerical studies of wear subsurface fracture under conditions of stress-induced martensitic transformation were used to elucidate the role played by the phase transformation in Y-TZP and Y-TZP-Al_2O_3. Martensitic transformation in Y-TZP was described with use of the non-associated dilatant plasticity model. Simulation results particularly show that increase in the value of dilatancy coefficient from 0 to 0.2 is accompanied by 25%-30% reduce in characteristic length and penetration depth of sliding-induced subsurface cracks. As shown the AE may be an effective tool for in-situ monitoring the subsurface wear of materials experiencing both direct and inverse transformations.

关键词： zirconia transformation toughening low-temperature degradation friction acoustic emission numerical modeling movable cellular automata method

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氢化石油树脂对流延聚丙烯薄膜性能的影响

塑料工业 2024年第2期52卷 141-144,164页

作者：林寿炜黑彦飞徐董卫益忠方晨张睿朱可夫·伊弗格尼于博士浙江金田高分子研究院有限公司浙江温州325000 温州金田塑业有限公司CPP事业部浙江温州325000 南京信息工程大学化学与材料学院江苏南京210044 德国罗斯托克大学罗斯托克18051

本文重点研究氢化石油树脂加入流延聚丙烯薄膜后,薄膜性能的变化和改善。不同含量的氢化石油树脂(C9)被加入聚丙烯薄膜,其质量分数控制在0~20%。研究表明,氢化石油树脂的质量分数达到20%,流延薄膜的水汽透过率下降41.3%。薄膜的纵横向... 详细信息

本文重点研究氢化石油树脂加入流延聚丙烯薄膜后,薄膜性能的变化和改善。不同含量的氢化石油树脂(C9)被加入聚丙烯薄膜,其质量分数控制在0~20%。研究表明,氢化石油树脂的质量分数达到20%,流延薄膜的水汽透过率下降41.3%。薄膜的纵横向拉伸强度与氢化石油树脂添加量之间影响不大,而纵向拉伸强度逐渐下降。氢化石油树脂加入,会大幅度减小雾度,但对透光率影响较小。随着氢化石油树脂的质量分数增加到20%,热封温度从172℃降低到166℃。

关键词：氢化石油树脂流延薄膜聚丙烯透水性拉伸强度透光率热封性

Electromagnetic Waves Absorbing Characteristics of Composite Material Containing Carbonyl Iron Particles

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Materials Sciences and Applications 2014年第11期5卷 803-811页

作者： Victor A. Zhuravlev Valentin I. Suslyaev evgeny yu. Korovin Kyrill V. Dorozhkin Department of Radioelectronics National Research Tomsk State University Tomsk Russia

Results of measurements of permeability, permittivity and radar absorption properties of composites on basis of carbonyl iron particles R-10 brand are presented in this paper. The calculations and experimental studies have shown that in the super high frequency (SHF) and extremely high frequency (EHF) ranges on the basis of two-layer structures with different content of carbonyl iron particles can create a radar absorbing coatings with a reflectivity of less than -10 dB over a wide bandwidth from 3.1 to 17.1 GHz and from 27 to 37 GHz. Absorbing properties of composites are saved in terahertz frequency range from 250 to 525 GHz.

关键词： Electromagnetic Wave Absorbers Radar Absorbing Materials and Coatings Composite Materials Carbonyl Iron Powders Spectrum of Permittivity and Permeability

Population dynamics of Amur tigers(Panthera tigris altaica)in Sikhote-Alin Biosphere Zapovednik:1966–2012

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Integrative Zoology 2015年第4期10卷 315-328页

作者： Dale G.MIQUELLE evgeny N.SMIRNOV Olga yu.ZAUMYSLOVA Svetlana V.SOUTYRINA Douglas H.JOHNSON Wildlife Conservation Society BronxNew YorkUSA Sikhote-Alin Biosphere Zapovednik TerneiPrimorskii KraiRussia USGS Northern Prairie Wildlife Research Center Saint PaulMinnesotaUSA

In 2010,the world’s tiger(Panthera tigris)range countries agreed to the goal of doubling tiger numbers over 12 years,but whether such an increase is biologically feasible has not been ***-term monitoring of tigers in Sikhote-Alin Biosphere Zapovednik(SABZ),Russia provided an opportunity to determine growth rates of a recovering population.A 41-year growth phase was followed by a rapid decline in tiger *** growth rates during the growth phase averaged 4.6%,beginning near 10%in the earliest years but quickly dropping below 5%.Sex ratio(females per male)mirrored growth rates,declining as population size *** rapid decline from 2009 to 2012 appeared to be tied to multiple factors,including poaching,severe winters and *** indicators of this population are similar to those of Bengal tiger populations,suggesting that growth rates may be *** results suggest that,first,tiger populations likely in general grow slowly:3–5%yearly increases are realistic and larger growth rates are likely only when populations are highly depressed,mortality rates are low and prey populations are high relative to numbers of adult ***,while more research is needed,it should not be assumed that tiger populations with high prey densities will necessarily grow more quickly than populations with low prey ***,while growth is slow,decline can be ***,because declines can happen so quickly,there is a constant need to monitor populations and be ready to respond with appropriate and timely conservation interventions if tiger populations are to remain ***,an average annual growth rate across all tiger populations of 6%,required to reach the Global Tiger Initiative’s goal of doubling tiger numbers in 12 years,is a noble but unlikely scenario.

关键词： Amur tiger growth rates population dynamics

Renal artery denervation suppresses intractable ventricular arrhythmia in patients with left heart thrombosis

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Journal of Geriatric Cardiology 2017年第9期14卷 587-589页

作者： Marianna A Vander Petr A Fedotov Tamara A Lyu.imtseva Maria A Bortsova Maria yu.Simikova Dmitry S Lebedev evgeny N Mikhaylov Neuromodulation Unit Almazov National Medical Research Centre Saint-Petersburg Russia Arrhythmia Department Almazov National Medical Research Centre Saint-Petersburg Russia Heart Failure Department Almazov National Medical Research Centre Saint-Petersburg Russia

Transcutaneous renal artery denervation （RND） has beeninitially developed for destruction of efferent nerve fireswith luminal delivery of radiofrequency or ultrasonic energyaiming blood pressure reduction in patients with refractoryhypertension. However, other positive results of RNDwere described afterwards, and they include suppression ofatrial fibrillation and ventricular tachycardia （VT） storm.

关键词： Renal nerve denervation Sympathetic nerve activity Ventricular tachyarrhythmias

Biodegradable Protection for Medical Devices with Medical Drugs Controlled Separation

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Journal of Pharmacy and Pharmacology 2016年第5期4卷 226-230页

作者： Milentina V. Seregina evgeny A.Nemets Alina A. Akhmedova Pavel B. Kurapov Elena yu. Bachtenko Laboratory of Tissue Engineering and Delivery Systems Shumakov Federal Research Center of Transplantology and ArtificialOrgans Schukinskaya street 1 Moscow 117997 Russia Department of Medical Nanobiotechnologies Pirogov Russian State Medical University Moscow 117997 Russia Vologda State University Vologda 160000 Russia

With the aim of creating biodegradable materials for medical devices clinical appointments with high hemocompatibility we have developed a new polymer *** basis of this product is plasticized by polyethylene glycol bacterial copolymer of hydroxybutyrate and oxovalerate. A well-known antitbrombotic supplement--acetylsalicylic acid has been added to improve hemocompatibility in the polymer. The results of our studies showed a controlled prolonged separation of acetylsalicylic acid from polymeric material in the blood. We studied in vitro the dynamics of liberation of acetylsalicylic acid from polymeric coatings. It was shown that the concentration of polyethylene glycol and the thickness of the polymer layer can affect the rate of diffusion of acetylsalicylic acid from polymer films.

关键词： Bacterial biodegradable copolymers poly (hydroxybutyrate-co-oxovalemte) hemocompatible medical devices forclinical application polyethylene glycol acetylsalicylic acid.

Targeting of the AKT/m-TOR Pathway: Biomarkers of Resistance to Cancer Therapy——AKT/m-TOR Pathway and Resistance to Cancer Therapy

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中国肺癌杂志 2018年第1期21卷 63-66页

作者： Liudmila V SPIRINA Irina V KONDAKOVA Natalia V TARASENKO Elena M SLONIMSKAYA evgeny A USYNIN Alexey K GORBUNOV Zahar A yu.MAZOV Svetlana yu.CHIGEVSKAYA Research Institute Tomsk National Research Medical Center of the Russian Academy of Sciences Russia

Resistance to cancer therapy continues to be a major limitation for the successful treatment of cancer. There are many published studies on therapy resistance in breast and prostate cancers; however, there are currently no data on molecular markers associated with resistance. The conflicting data were reported regarding the AKT/m-TOR signaling pathway components as markers predicting resistance. The AKT/m-TOR signaling pathway is involved in the development of many human cancers; its activation is related to cell proliferation, angiogenesis, apoptosis, as well as to therapy resistance. Molecular alterations in the AKT/m-TOR signaling pathway provide a platform to identify universal markers associated with the development of resistance to cancer therapy.

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Influence of monovalent Bi^+doping on real composition,point defects,and photoluminescence in TlCdCl3 and TlCdI3 single crystals

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Science China Materials 2017年第12期60卷 1253-1263页

作者： Daria N.Vtyu.ina Polina A.Eistrikh-Geller Galina M.Kuz mlcheva Victor B.Rybakov evgeny V.Khramov Irina A.Kaurova Dmitry yu.Chernyshov Vladimir N.Korchak Semenov Institute of Chemical Physics Russian Academy of SciencesMOSCOW 119991Russia Institute of Fine Chemical Technologies Moscow Technological UniversityMoscow 119571Russia Lomonosov State University Moscow 119992Russia National Research Center《Kurchatov Instituters》 Moscow 123182Russia Swiss-Norwegian Beamlines at the European Synchrotron Radiation Facility Grenoble 38000France

The structural features and real compositions with point defects of Bi+-doped TlCdCl_3 and TlCdI_3 single crystals, grown by the Bridgman-Stockbarger technique, are first studied using the X-ray diffraction, X-ray synchrotron radiation, and EXAFS/XANES spectroscopy. In the structures of Bi^+-doped TlCdCl_3 and TlCdI_3 crystals, the Cd, Cl, and I sites are found to be defect-free. The vacancies in the Tl sites and interstitial Bi atoms located in the vicinity of the Tl sites are detected in the structures of both samples. In the Bi^+-doped TlCdCl_3, the presence of a small amount of Bi^+ ions in the Tl^+ sites is possible. The correlation between photoluminescence bands and point defects in the refined structures are determined. Photoluminescence spectra and decay kinetics of the Bi+-doped TlCdCl_3 and TlCdI_3 demonstrate that they are attractive materials for potential applications in photonics.

关键词： single crystal growth doping crystal structure point defects photoluminescence