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Transactions of Nonferrous Metals Society of China 2022年第9期32卷 2993-3004页

作者： Guo-long WU Shuo ZHANG Ye WANG Min SUN Qun-li ZHANG Volodymyr kovalenko Jian-hua YAO College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310014China Institute of Laser Advanced Manufacturing Zhejiang University of TechnologyHangzhou 310014China Collaborative Innovation Center of High-end Laser Manufacturing Equipment Zhejiang University of TechnologyHangzhou 310014China Laser Technology Research Institute National Technical University of Ukraine“Kiev Polytechnic Institute”Kiev03056Ukraine

In order to improve the bioactivity of 316L stainless steel,a titanium layer was prepared on the surface of 316L by laser cladding(LC),followed by plasma electrolytic oxidation(PEO)to form a porous ceramic coating on titanium *** morphologies,microstructure and compositions of the coated samples were characterized by 3D surface profiler,SEM,EDS,XRD and *** corrosion resistance and bioactivity of the coatings were evaluated by potentiodynamic polarization and immersion test in simulated body fluid(SBF),*** results showed that the porous ceramic coating mainly consisted of anatase and rutile,and highly crystalline HA was also *** main elements of the PEO coating are Ca,P,Ti and *** LC+PEO composite bio-coating has more excellent corrosion resistance than the 316L substrate in simulated body ***,the composite coating could effectively improve the bioactivity of 316L stainless steel.

关键词： 316L stainless steel laser cladding titanium plasma electrolytic oxidation bioactivity

Clay Minerals Properties as Downhole Formation Pressure Indicator

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Journal of Chemistry and Chemical Engineering 2011年第11期5卷 990-994页

作者： Dmitry Kozhevnikov Kazimir kovalenko Andrey Gorodnov Ivan Deshenenkov Well Logging Department Gublan Russian State University of Oil and Gas Moscow 119991 Russia

The successful estimation of formation pressures （or formation pore gradient） is fundamental and the basis for many engineering works including drilling and oilfield development planning. Common log data are used for formation pressure calculation. Modern techniques for pressure prediction have several disadvantages, notably, incorrect account of the downhole nonsteady thermal field and clay mineral composition. We propose a way to overcome listed shortcomings： a technique for thermal field proper account while formation pressure estimation and a petrophysical model, which reflects relationships between clay minerals composition and rock properties, derived from log data.

关键词： Formation pressure clay minerals overpressure temperature effect undercompaction petrophysics log data.

超音速激光沉积Ti-6Al-4V合金结合界面特征数值模拟及试验验证

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表面技术 2020年第8期49卷 324-332页

作者：汪伟林吴丽娟李波 Volodymyr kovalenko 张群莉姚建华浙江工业大学激光先进制造研究院杭州310023 浙江工业大学机械工程学院杭州310023 乌克兰国立科技大学激光技术研究所乌克兰基辅03056

目的探究超音速激光沉积(SLD)过程中激光辐照温度和颗粒撞击速度对Ti-6Al-4V合金结合界面特征的影响规律,并通过试验对数值模拟结果进行验证。方法基于Johnson-cook材料模型,利用ABAQUS 2017软件并采用欧拉-拉格朗日耦合CEL(Coupled Eul... 详细信息

目的探究超音速激光沉积(SLD)过程中激光辐照温度和颗粒撞击速度对Ti-6Al-4V合金结合界面特征的影响规律,并通过试验对数值模拟结果进行验证。方法基于Johnson-cook材料模型,利用ABAQUS 2017软件并采用欧拉-拉格朗日耦合CEL(Coupled Euler-Lagrange)计算模型和Lagrange计算模型,进行Ti-6Al-4V单颗粒和多颗粒的撞击行为数值模拟,并结合超音速激光沉积试验验证模拟结果。采用扫描电镜(SEM)和光镜(OM)对涂层的界面结合特征进行观察和分析。结果单颗粒撞击温度场模拟结果表明,当激光辐照温度为1073 K时,随着撞击速度的增加,颗粒界面结合温度不断升高。当撞击速度为800 m/s和900 m/s时,颗粒与基体局部最高温度分别为1876.7 K和1874.8 K,界面发生微熔。800 m/s时,颗粒压缩率为34.3%,扁平率为1.27,有效塑性应变为2.6,基体的凹坑深度为7.88μm,该参数下的超音速激光沉积涂层界面结合良好。多颗粒撞击温度场模拟结果表明,当撞击速度为800 m/s时,随着激光辐照温度的升高,孔隙逐渐减少。激光辐照温度为1073 K时,颗粒撞击界面的温度高达3463.7 K,但颗粒内部的温度还未达到熔点并保留在1073~1676.8 K。随着激光功率的升高,钛合金涂层的孔隙率降低为0.67%(SLD 700W),约为同条件下CS涂层孔隙率(8.31%)的1/12。结论激光辐照的热能使颗粒与基体以及颗粒间界面处的温度达到了材料熔点,实现颗粒表面微熔形成冶金结合。冷喷涂Ti-6Al-4V涂层中,颗粒与基体以及颗粒间均存在明显的孔隙,超音速激光沉积Ti-6Al-4V涂层颗粒与基体以及颗粒间的界面结合良好,试验结果与数值模拟结果大致吻合。

关键词：超音速激光沉积 Ti-6Al-4V CEL 微熔界面结合

INFLUENCE OF CYTOCHROME P-450 INDUCTION ON RAT MALE GONADOTOXIC EFFECTS

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INFLUENCE OF CYTOCHROME P-450 INDUCTION ON RAT MALE GONADOTO...

前驱体对激光熔覆复合溶胶凝胶制备陶瓷涂层的影响

第十五届国际药理学大会

作者： Saprykina Nataliia Bondarenko Larisa kovalenko Valentina Institute of Pharmacology and Toxicology Academy of Medical Science of Ukraine Kiev Institute of Pharmacology and Toxicology Academy of Medical Science of Ukraine Kiev Institute of Pharmacology and Toxicology Academy of Medical Science of Ukraine Kiev

＜正＞ Introduction: Important roles in xenobiotics multilevel influence on spermatogenesishave highly reactive metabolites and oxygen active forms produced during their biotransformation with cytochrome P - ***: investigaton of pyrazinamide （cytochrome P - 45021 inductor） effects on functional, morphologic and biochemical parameters of rat testis. Methods: Pyrazinamide （500,1000,2000 mg per kg） was administered to rats during all period of spermatogenesis. Lipids. nucleic acids, histones contents, morphologic changes, functional state of spermatozoid were investigated in testis. Results: Pyrazinamide （1000 and 2000 mg/kg b. w.） lowered spermatozoids number to 22.5% . spermatogonia- to 38.8%. increased spermatocytes meiotic activity to 87.8% . caused changes of cholesterol. DNA. RNA and histones contents . Dose 2000 mg/kg b.w. also caused degenerative changes in testis seminiferous ***: xenobiotics effects on male reproductive system tightly connected with its cytochrome P450 2E1 - dependent metabolism.

关键词： pyrazinamide. cytochrome P450 21. rat testis

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表面技术 2019年第2期48卷 1-9页

作者：张群莉姚中志周塘姚建华 Volodymyr S.kovalenko 浙江工业大学激光先进制造研究院杭州310014 浙江工业大学机械工程学院杭州310014 乌克兰国立科技大学激光技术研究所乌克兰基辅03056

目的研究不同前驱体配比下,激光熔覆复合溶胶凝胶在3Cr13不锈钢表面制备的陶瓷涂层的性能,并对强化机理进行分析。方法通过溶胶凝胶法制备均匀的前驱体,即Ti O2和C(微米石墨和碳纳米管),利用激光熔覆技术,在3Cr13不锈钢基体表面制备出... 详细信息

目的研究不同前驱体配比下,激光熔覆复合溶胶凝胶在3Cr13不锈钢表面制备的陶瓷涂层的性能,并对强化机理进行分析。方法通过溶胶凝胶法制备均匀的前驱体,即Ti O2和C(微米石墨和碳纳米管),利用激光熔覆技术,在3Cr13不锈钢基体表面制备出高性能的涂层。采用光学显微镜、X射线衍射仪、扫描电镜和能谱仪对涂层组织和相成分进行分析,采用维氏硬度计对涂层的硬度进行测试,采用HT-600型高温摩擦磨损试验机测试基体和熔覆层在常温下的磨损性能。结果通过溶胶凝胶法,制备出均匀的Ti O2和C混合粉末。激光熔覆后,在覆层中均匀分布着Ti C和Cr7C3强化相。改变前驱体配比,当C和Ti O2的摩尔比增大时,涂层组织明显细化,且涂层中无气孔,显微硬度也有较大提高。当n(TiO2)∶n(C)=1∶8时,次表面显微硬度达到810HV0.2,涂层硬度从上到下呈现递减的趋势,且涂层的耐磨性最好,为基体的4.5倍。结论增大C和Ti O2两者摩尔比,可以提高熔覆层的显微硬度和耐磨性。在熔池中,Ti C密度较小,涂层中硬质颗粒从上到下依次减少,与之对应,硬度也依次递减。同时,碳纳米管的加入将对涂层起到细晶强化的效果。Ti与碳纳米管和微米石墨结合生成微米级和亚微米级Ti C,提高了形核率,Cr7C3以亚微米级Ti C为非均质核心,形核长大,生成均匀分布的Cr7C3强化相。

关键词：激光熔覆溶胶凝胶 3Cr13不锈钢 TiC Cr7C3 碳纳米管

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激光辅助化学气相沉积研究进展

光电工程 2022年第2期49卷 1-29页

作者：范丽莎刘帆吴国龙 Volodymyr S.kovalenko 姚建华浙江工业大学激光先进制造研究院浙江杭州310023 浙江工业大学机械工程学院浙江杭州310023 高端激光制造装备省部共建协同创新中心浙江杭州310023 乌克兰国立科技大学激光技术研究所乌克兰基辅03056

激光化学气相沉积技术(LCVD)相较于传统化学气相沉积技术具有低沉积温度、高膜层纯度、高沉积效率等特点,在各类功能薄膜材料制备上有着巨大的应用前景。围绕激光化学气相沉积技术,本文详细阐述了激光热解离、激光光解离与激光共振激发... 详细信息

激光化学气相沉积技术(LCVD)相较于传统化学气相沉积技术具有低沉积温度、高膜层纯度、高沉积效率等特点,在各类功能薄膜材料制备上有着巨大的应用前景。围绕激光化学气相沉积技术,本文详细阐述了激光热解离、激光光解离与激光共振激发解离作用机制,同时介绍了各类LCVD的常用设备,着重总结了LCVD在金属材料、碳基材料、氧化物材料以及半导体材料等各类材料制备应用上的最新研究进展,特别介绍了LCVD制备过程中常用的检测与分析方法,最后讨论了激光化学气相沉积技术目前所面临的挑战与机遇,并展望了该技术的发展前景。

关键词：激光化学气相沉积薄膜制备热解离光解离共振激发解离

液态二氧化碳对俄罗斯某油藏稠油的膨胀与萃取作用实验

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石油勘探与开发 2018年第5期45卷 861-868页

作者： LOBANOV A A SHHEKOLDIN K A STRUCHKOV I A ZVONKOV M A HLAN M V PUSTOVA E J kovalenko V A ZOLOTUKHIN A B Northern(Arctic)Federal University ArkhangelskRussian Federation JSC RITEK SamaraRussian Federation Saint-Petersburg Mining University Saint PetersburgRussian Federation

利用俄罗斯某油藏稠油样品,通过实验分析稠油与液态CO_2混合后两者之间的质量传递作用以及混合物中重相(稠油和CO_2的混合物)和轻相(纯CO_2)的特性变化。研究表明,当混合物中CO_2浓度为10%时,稠油基本上不发生膨胀;当混合物中CO_2浓度高... 详细信息

利用俄罗斯某油藏稠油样品,通过实验分析稠油与液态CO_2混合后两者之间的质量传递作用以及混合物中重相(稠油和CO_2的混合物)和轻相(纯CO_2)的特性变化。研究表明,当混合物中CO_2浓度为10%时,稠油基本上不发生膨胀;当混合物中CO_2浓度高于26%时,由于稠油轻质组分的萃取量超过了CO_2在稠油中的饱和量导致重相体积减少,重相黏度呈指数增长,混合物中CO_2的浓度为26%时,有效降低重相黏度的作用最强;重相和轻相密度、体积系数、气体溶解度和闪蒸重相黏度均随着混合物中CO_2浓度的增加而变大;混合物中最佳的CO_2浓度是26%,此时稠油膨胀最大、重相的黏度值最小;混合物中CO_2的浓度为10%~26%时,轻相的体积最小,驱油效果最好。

关键词：提高采收率 CO2 稠油膨胀实验萃取实验相态特征

The Research of Fractal Characteristics of the Electrocardiogram in a Real Time Mode

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Journal of Mathematics and System Science 2012年第3期2卷 191-195页

作者： Valery Antonov Anatoly kovalenko Artem Zagaynov Vu Van Quang St. Petersburg State Polytehnical University St. Petersburg 195251 Russia loffe Physical-Technical Institute of the Russian Academy of Sciences St. Petersburg 194021 Russia

The article presents the results of recent investigations into Holter monitoring of ECG, using non-linear analysis methods. This paper discusses one of the modern methods of time series analysis--a method of deterministic chaos theory. It involves the transition from study of the characteristics of the signal to the investigation of metric （and probabilistic） properties of the reconstructed attractor of the signal. It is shown that one of the most precise characteristics of the functional state of biological systems is the dynamical trend of correlation dimension and entropy of the reconstructed attractor. On the basis of this it is suggested that a complex programming apparatus be created for calculating these characteristics on line. A similar programming product is being created now with the support of RFBR. The first results of the working program, its adjustment, and further development, are also considered in the article.

关键词： Holter monitoring ECG correlation dimension fractal analysis of time series non-linear dynamics of heart rate

New Extracellular Bacillus subtilis Lectins with Sialic Acid-Specificity

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Journal of Agricultural Science and Technology(A) 2014年第6期4卷 541-546页

作者： Valentin Podgorsky Emma kovalenko Iryna Karpova Elena Sashchuk Ekaterina Getman Department of Physiology of Industrial Microorganisms Zabolotny Institute of Microbiology and Virology National Academy ofSciences of Ukraine Kyiv D03680 Ukraine Department of Human Genetics Institute of Molecular Biology and Genetics NatiGnal Academy of Sciences of Ukraine KyivD03143 Ukraine

The purpose of this work is to perform a detailed study of carbohydrate specificity of the new extracellular bacilli lectins which is considered to determine mechanisms of the lectins action. Sources of lectins were bacterial strains from Ukrainian collection of microorganisms. The optimized protocol of bacilli lectins isolation and purification included precipitation with ammonium sulfate with subsequent gel filtration chromatography on Sepharose CL-6B. Hemagglutinating activity of bacilli lectins and their fine carbohydrate specificity to sialic acids and their derivatives as well as sialic asid-containing and asialic glycoconjugates were studied. The ability of extracellular bacilli lectins to discriminate a- and 13-conformation of carbohydrate molecule and the type of connection between the monomers was determined. Studied lectins showed the most affinity to glycoconjugates containing both types of sialic acids （N-acetylneuraminic acid （Neu5Ac） and N-glycolylneuraminic acid （NeuGc）） and it is supposed to be a basis of their diagnostic and analytical potential.

关键词： Bacillus subtilis lectins sialic acids specificity.

Influence of Fast Global Variations of Solar Magnetic Fields on Space Weather in Cycle 23

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空间科学学报 2005年第5期25卷 460-467页

作者： S. I. Molodykh G. A. Zherebtsov V. A. kovalenko J. X. Wang V. I. Sidorov Institute of Solar-Terrestrial Physics Siberian Branch Russian Academy of Sciences Irkutsk 664033 Russia National Astronomical Observatory Chinese Academy of Sciences

It is established that the large-scale and global magnetic fields in the Sun's atmosphere do not change smoothly, and long-lasting periods of gradual variations are superseded by fast structural changes of the global magnetic field. Periods of fast global changes on the Sun are accompanied by anomalous manifestations in the interplanetary space and in the geomagnetic field. There is a regular recurrence of these periods in each cycle of solar activity, and the periods are characterized by enhanced flaring activity that reflects fast changes in magnetic structures. Is demonstrated, that the fast changes have essential influencing on a condition of space weather, as most strong geophysical disturbances are connected to sporadic phenomena on the Sun. An explanation has been offered for the origin of anomalous geomagnetic disturbances that are unidentifiable in traditionally used solar activity indices. Is shown, main physical mechanism that leads to fast variations of the magnetic fields in the Sun's atmosphere is the reconnection process.

关键词：太阳活动磁场空间气候大气动态变化太阳光