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Intervalley Scattering of Electrons in n-Si at T = 77 ÷450 K

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World Journal of Condensed Matter Physics 2013年第1期3卷 43-45页

作者： Valerii Ermakov volodymyr Kolomoets Leonid Panasyuk Baja Orasgulyev Caspian State University Aktau Kazakhtan V. Lashkaryov Institute for Semiconductor Physics NAS of Ukraine Kiev Ukraine

The change in electron mobility of n-Si with increasing the temperature which may be due to the inclusion of gLOphonon energy of 720 K, is presented. Under orientation of the uniaxial pressure X//[110]//J, g-transitions are attached in the directions [100] and [010]. The f-transitions are not completely removed from valleys located in the plane (100). In this case, there is no change in the slope of the dependence logρ vs. logT for the temperature range 77 to 450 K. So, no appreciable contribution of g-transitions to intervalley scattering occurs, while the observed is the decisive role of f-transitions to intervalley scattering. The results of measuring of the tensoresistivity effect for n-Si crystals under X//[001]//J are presented at these temperatures too.

关键词： Silicon f-Transitions g-Transitions Tensoresistivity Effect Uniaxial Strain

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

基于柔性双(甲基苯并咪唑)和羧酸配体的Cd(Ⅱ)/Co(Ⅱ)/Zn(Ⅱ)配合物的合成和表征（英文）

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无机化学学报 2019年第9期35卷 1642-1650页

作者：张兆沛 Vlasenko volodymyr Anatoliyovych 刘润强杨里刘露张裕平河南科技学院生命科技学院河南科技学院现代生物育种河南省协同创新中心新乡453003 Agrotechnologies and Environmental Use Department Sumy National Agrarian University Sumy 40021 Ukraine 河南科技学院资源与环境学院新乡453003 河南科技学院化学化工学院新乡453003

通过水热或溶剂热合成的方法制备了3个Cd(Ⅱ)/Co(Ⅱ)/Zn(Ⅱ)配位聚合物[Cd(hbmb)0.5(pta)]n(1),[Co(hbmb)(1,4-bdc)]n(2)和{[Zn2(hbmb)1.5(bptc)(H2O)]·0.5hbmb·3H2O}n(3)(hbmb=1,1′-(1,6-己烷)双-(2-甲基苯并咪唑),H2pta=邻羧基苯乙酸,1,4-H2bdc=1,4-苯二乙酸, H4bptc=3,3′,4,4′-二苯甲酮四羧酸))。单晶结构解析表明配合物1是一个4-连接的二维平面网络,拓扑符号为(44·62)。配合物2是一个4-连接的二维褶皱网络,拓扑符号为(42·6)(42·63·8)。配合物3是一个(3,4,4)-连接的三重穿插网络,拓扑符号为(42·62·82)(4·62)(4·64·8)。其中配合物1属于单斜晶系,空间群为P21/c,a=0.758 32(15) nm,b=1.452 8(3) nm,c=1.911 3(5) nm,β=112.26(3)°,Z=4;配合物2属于单斜晶系,空间群为P21/n,a=1.090 8(2) nm,b=1.873 1(4) nm,c=1.301 9(3) nm,β=91.09(3)°,Z=4;配合物3属于三斜晶系,空间群为P1,a=1.119 6(2) nm,b=1.481 2(3) nm,c=1.926 6(4) nm,α=89.72(3)°,β=87.65(3)°,γ=68.28(3)°,Z=2。

关键词：配合物晶体结构拓扑

X-Ray Diffractometry and Raman Spectroscopy Investigation of Irradiated Layered III-VI Crystals

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材料科学与工程（中英文A版） 2012年第7期2卷 537-543页

作者： Zakhar Dmytrovych Kovalyuk Oleg Mykolayovych Sydor Oksana Anatoliivna Sydor volodymyr Grygorovych Tkachenko Igor Mykolayovych Maksymchuk volodymyr Ivanovych Dubinko Pavlo Mykolayovych Ostapchuk Chernivtsi Department of the Institute of Materials Science Problems Chernivtsi 58001 Ukraine Institute of Materials Science Problems Kyiv 03680 Ukraine National Scientific Center "Kharkiv Physico-Technical Institute " Kharkiv 61108 Ukraine

The present results of investigations of the influence of irradiation on layered n-InSe, p-InSe, and p-GaSe semiconductors. Two types of irradiation are considered: (1) the bremsstrahlung ?-quanta with effective energy of 3MeV and the irradiation dose ranging from 0.14 to 140 kGy and (2) 12 MeV electron irradiation up to the dose ranging from 3.3 to 33 MGy. The crystal structure, lattice parameters, and atom coordination environment were investigated by means of X-ray structure analysis and Raman spectra measurements. It is shown that all samples under investigation have high structural perfection. It is shown that even the maximum dose levels of ?-quanta and electrons did not caused qualitative changes in the investigated spectra, which indicates that the influence of the irradiation on the subsystems of vacancies and impurities in InSe and GaSe is insignificant. Possible physical phenomena occurring in the layered crystals subjected to irradiation are described. It is suggested tentatively that the dopant atoms of Cd in p-InSe are the centers for localization of radiation-induced vacancies, whereas in the intentionally undoped crystals, the vacancies are localized in the sublattices of In or Ga. These results enable one to consider layered semiconductors as potential candidates for preparation of radiation-resistant photoconverters or detectors of high-energy particles.

关键词： X-射线衍射拉曼光谱电子辐照晶体结构照射剂量层状晶体晶格常数调查结果

Simulation of Modes of Ionosphere Alfven Resonator with High Quality Factors in the Case of Oblique Geomagnetic Field

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Journal of Electromagnetic Analysis and Applications 2012年第5期4卷 192-198页

作者： volodymyr Grimalsky Svetlana Koshevaya Anatoliy Kotsarenko Marco A. Cruz Chavez Autonomous University of State Morelos (UAEM) CIICAp Morelos Mexico Center of Geoscience UNAM is Autonomous National University of Mexico (UNAM) Queretaro Mexico

The properties of the ionosphere Alfvén resonator (IAR) in the general case of an oblique geomagnetic field are investigated. The modes at the frequencies f = 0.2 - 10 Hz well localized within the ionosphere are considered, which are important for the lithosphere—ionosphere coupling. An attention is paid to the modes with quite high quality factors , where . A proper selection of calculated eigenfrequencies has been realized. Two independent simulation algorithms have been proposed. The resonant frequencies and the profiles of magnetic field components of the modes have been calculated. The modulation of electron and ion concentrations at the heights 170 - 230 km leads to essential shifting the resonant frequencies.

关键词： Alfvén Resonator Resonant Modes Quality Factors Modulation

316L表面激光熔覆复合微弧氧化制备陶瓷涂层

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表面技术 2019年第2期48卷 24-32页

作者：孙敏吴国龙王晔张群莉姚建华 volodymyr S.Kovalenko 浙江工业大学激光先进制造研究院杭州310014 浙江省高端激光制造装备协同创新中心杭州310014 乌克兰国立科技大学激光技术研究所乌克兰基辅03056

目的提高316L不锈钢表面的耐蚀性和生物活性。方法首先采用激光熔覆技术在316L不锈钢表面制备钛层,然后对钛层表面进行微弧氧化处理,从而在316L不锈钢表面制备出含有Ca、P元素的多孔状陶瓷涂层。利用扫描电子显微镜(Scanning Electron M... 详细信息

目的提高316L不锈钢表面的耐蚀性和生物活性。方法首先采用激光熔覆技术在316L不锈钢表面制备钛层,然后对钛层表面进行微弧氧化处理,从而在316L不锈钢表面制备出含有Ca、P元素的多孔状陶瓷涂层。利用扫描电子显微镜(Scanning Electron Microscope,SEM)、能谱仪(Energy Dispersive Spectrometer,EDS)、X射线衍射仪(X-Ray Diffraction,XRD)分析了钛层厚度对陶瓷涂层的表面显微形貌、元素含量及物相组成的影响。利用电化学实验、浸泡实验分别测试了涂层在1.5倍SBF溶液中的耐蚀性能和生物活性。结果通过激光熔覆复合微弧氧化能够在316L不锈钢表面制备出多孔状陶瓷涂层。随着钛层厚度的增加,微弧氧化原位生成的陶瓷涂层致密度、厚度也增加。当钛层厚度达到0.4 mm时,微弧氧化后得到的陶瓷涂层完整致密,厚度达到20μm。涂层主要由锐钛矿相Ti O2、金红石相Ti O2组成。极化曲线分析可知,腐蚀电位Ecorr为-0.162 V,腐蚀电流密度降至5.11×10-7 A/cm2。陶瓷涂层在1.5倍SBF中浸泡3天后表面即有羟基磷灰石沉积。结论通过激光熔覆复合微弧氧化在316L不锈钢表面制备的陶瓷涂层在模拟体液环境下具有较好的耐蚀性能,同时也具备良好的生物活性。

关键词： 316L 激光熔覆微弧氧化生物活性耐蚀性

Deposition of BaTiO3 Films from EthanoI-PVB Medium

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Journal of Chemistry and Chemical Engineering 2014年第6期8卷 564-569页

作者： Maksim Zagorny Anna Ivanchuk volodymyr Pidsosonnyi Alexander Zhygotsky Andrey Ragulya Department of Physical Chemistry and Technology of Nanostructure Ceramic and Composites Ivan Nikitovich Frantsevich Institutefor Problems of Materials Science of the National Academy of Sciences of Ukraine Kiev 03680 Ukraine

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定向洛伦兹力对激光熔覆熔池排气的影响

中国激光 2018年第8期45卷 56-65页

作者：胡勇王梁李珏辉张群莉姚建华 volodymyr Kovalenko 浙江工业大学激光先进制造研究院浙江杭州310014 浙江省高端激光制造装备协同创新中心浙江杭州310014 乌克兰国立科技大学激光技术研究所乌克兰基辅03056

采用稳态磁场和电场耦合形成定向洛伦兹力,基于多物理场耦合原理及网格变形法建立了定向洛伦兹力作用下的熔池模型,采用离散元法模拟了熔池内的气泡运动过程。与熔覆工艺条件相同但未施加外场时比较,结果显示,定向洛伦兹力具有优异的气... 详细信息

采用稳态磁场和电场耦合形成定向洛伦兹力,基于多物理场耦合原理及网格变形法建立了定向洛伦兹力作用下的熔池模型,采用离散元法模拟了熔池内的气泡运动过程。与熔覆工艺条件相同但未施加外场时比较,结果显示,定向洛伦兹力具有优异的气孔调控能力。当洛伦兹力向上时,熔池的最高流速被抑制了62.5%,气泡运动方向向下偏转,熔覆层的气孔明显增多;当洛伦兹力向下时,熔池的最高流速被抑制了25%,但气泡因所受浮力增大而逸出加速,熔覆层无气孔。仿真结果与实验结果吻合良好,验证了仿真模型的可靠性。

关键词：激光技术激光熔覆熔池气孔定向洛伦兹力多物理场

Influence of Impurity Doping and γ-Irradiation on the Optical Properties of Layered GaSe Crystals

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材料科学与工程（中英文B版） 2012年第2期2卷 91-102页

作者： Yuriy I. Zhirko Nikolay A. Skubenko volodymyr I. Dubinko Institute of Physics National Academy of Sciences of Ukraine Kharkiv Physical-and-Technical Institute NAS of Ukraine

Presented in this paper are the results of electron-microscopic (SEM, EDS) and low-temperature (Т = 4.5 K) photoluminescence (PL) and absorption investigations of layered GaSe crystals, both non-doped and doped with Zn, Cd and Sn impurities taken in the concentration 0.01 wt%. The crystals were exposed to ?-irradiation with energies 0 to 34 MeV and doses up to 1014 γ/cm2. SEM investigations did not reveal any structural changes at the crystal surface after ?-irradiation with the investigated doses. PL investigations enabled the discovery that doping GaSe crystals with Zn or irradiation of non-doped crystals with ?-quanta results in decreased amounts of intrinsic defects (according to Schottky and Frenkel, respectively) in these crystals. As a consequence, an essential increase in the parameter S0 (the integrated intensity of PL) was observed with increasing doses of ?-irradiation. In contrast, doping with Sn impurities resulted in a sharp drop in S0 that began to increase after irradiation with ?-quanta. It has been shown that ?-irradiation of GaSe crystals doped with Cd results in the appearance of wide bands in the PL and absorption spectra, caused by transitions of carriers between direct and indirect conduction bands and deep acceptor levels, as well as by transitions of the donor-acceptor type. The types of transitions, energies of acceptor levels (25, 70, 150, 310, 460 meV) relative to the top of valence band and the energy of the donor level (165 meV) relative to the bottom of the conduction band, as well as Huang-Rys factors and the energies of lattice phonons taking part in these transitions were determined.

关键词：晶体表面硒化镓非掺杂光学性质电子显微镜辐射光致发光晶体掺杂