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预制坡口角度对激光增材再制造IN718合金组织与性能的影响

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表面技术 2019年第5期48卷 90-96页

作者：张群莉李栋张杰姚建华 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

目的研究在激光增材再制造IN718合金过程中,不同预制坡口角度对其组织与性能的影响。方法利用激光增材再制造技术对不同预制凹槽进行逐层叠加修复,采用光学显微镜观察显微组织,采用扫描电镜观察断口形貌,采用维氏硬度计对再制造试样进... 详细信息

目的研究在激光增材再制造IN718合金过程中,不同预制坡口角度对其组织与性能的影响。方法利用激光增材再制造技术对不同预制凹槽进行逐层叠加修复,采用光学显微镜观察显微组织,采用扫描电镜观察断口形貌,采用维氏硬度计对再制造试样进行硬度测量,采用残余应力测试仪测量再制造后基体表面的残余应力,采用万能拉伸试验机进行拉伸力学性能测试。结果当预制坡口角度大于130°时,能得到无组织缺陷、成形质量良好的增材再制造试样;当预制坡口角度小于110°时,修复界面会出现熔合不良现象,且修复区内部会出现裂纹。预制大的坡口角度进行激光增材再制造试验能获得组织更加细密、硬度分布更为均匀的再制造层,且大的坡口角度能有效降低再制造试样基体的残余应力。增大坡口角度有助于提高再制造试样的塑性,随着坡口角度的减小,再制造试样的力学性能变差。结论在进行激光增材再制造试验时,不宜预制过小的坡口角度,应根据损伤情况预制坡口角度较大的凹槽,有助于增加再制造成形件的组织均匀性,提高其力学性能。

关键词：激光增材再制造 IN718高温合金坡口角度显微组织残余应力拉伸性能

Russian-Chinese Bilateral Trade in Fuel and Machinery Industries,Its Characteristics and Development

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Russian-Chinese Bilateral Trade in Fuel and Machinery Indust...

作者： Anna kovalenko 上海交通大学

学位级别：硕士

Since the beginning of the twenty-first century trade cooperation between Russia and China,especially from the point of view of bilateral trade is growing *** 2009,China became the first trading partner of *** structure of trade relations between the two countries is characterized by the expansion of sales of Russian mineral fuel,on the one hand,manufactured products and a strong rise in Chinese exports on the *** cooperation model creates an imbalance and prevent the expansion of ties,the diversification of exports to China.

关键词： Russia China Russian-Сhinese trade cooperation imbalance issue

Acetabular cup version modelling and its clinical applying on plain radiograms

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World Journal of Orthopedics 2017年第12期8卷 929-934页

作者： Anton Denisov Stanislav Bilyk Anton kovalenko Orthopedic Department Vreden Russian Research Institute of Traumatology and Orthopedics

AIM To measure the sensitivity and specificity of the cup version assessment by using only anteroposterior hip and pelvis views, evaluate the incidence of inadequate cup version in patients with repeated dislocations after total hip arthroplasty(THA). METHODS Radiographic retrospective analysis of 2 groups of patients, with follow up of 6-60 mo, after undergoing primary THA. First group of 32 patients(20 female, 12 male) with unilateral THA(32 hips) required early revision arthroplasty for reasons of dislocation. The mean age and mode were 59(from 38 to 83) and 66 ages respectively. The average body mass index(BMI) was 24.2(from 17.7 to 36.3), mode 23.9. Second group was consisted of 164 patients(101 female, 63 male) without dislocations during the follow-up period(170 hips). Among them 6 patients required bilateral THA. The mean age was 60(from 38 to 84) and mode 59. BMI was 24.8(17.2-36.8), mode 25.2. Clinical significance of the cup anteversion sign was estimated with cross tabulation 2 × 2. RESULTS The value of the χ~2 yates was 10.668(P < 0.01).Sensitivity of SAI(sign of anteversion insufficiency) was 29%(95%CI: 9%-46%), and specificity was 92%(95%CI: 88%-96%). Relative risk of dislocation in patients with SAI was 3.4(95%CI: 1.8-6.3). CONCLUSION This method provides the surgeons with the ability to perform a reliable and simple qualitative assessment of the acetabular component version. It can be useful during patient examination with early loosening of the implant, dislocations, and impingement. Additionally, it can provide necessary information during planning of revision surgery, especially when considering question about cup replacement, although final assessment of the cup position should be done with a computed tomography scan.

关键词： Hip arthroplasty Acetabular component Retroversion Dislocation

电磁复合场协同激光熔覆制备TiB_w/Ti网状结构复合涂层

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表面技术 2019年第5期48卷 102-107页

作者：袁莹林英华王梁张杰姚建华刘新新 volodymyr S.kovalenko 浙江工业大学激光先进制造研究院杭州310014 哈尔滨汽轮机厂有限责任公司哈尔滨150046 乌克兰国立科技大学激光技术研究所乌克兰基辅03056

目的利用电磁复合场(EMCF)辅助激光熔覆制备TiB_w/Ti网状结构复合涂层,探索电磁场对涂层组织结构的影响。方法以TiB_2∶Ti=1∶1(摩尔比)的混合粉末为熔覆材料,TC4作为基板材料,通过外加电磁复合场进行激光熔覆试验。通过扫描电子显微镜(... 详细信息

目的利用电磁复合场(EMCF)辅助激光熔覆制备TiB_w/Ti网状结构复合涂层,探索电磁场对涂层组织结构的影响。方法以TiB_2∶Ti=1∶1(摩尔比)的混合粉末为熔覆材料,TC4作为基板材料,通过外加电磁复合场进行激光熔覆试验。通过扫描电子显微镜(SEM)观察洛伦兹力方向对熔覆层组织结构的影响,利用X射线衍射仪(XRD)和维氏显微硬度计分析施加电磁复合场前后熔覆层的相组成和硬度分布。结果未施加电磁复合场的熔覆层组织主要为细针状、粗棒状和颗粒状组织。而施加电磁复合场后,熔覆层出现了网状结构,而且方向向下的洛伦兹力可使涂层内部形成空间间距更大的网状结构。此外,单独施加稳态磁场后,熔覆层只出现细针状和粗棒状组织。电磁复合场施加前后熔覆层硬度与基体相比,均有很大的提高。但未施加电磁复合场的熔覆层硬度变化幅度较大;施加电磁复合场后,随着距熔覆层表面距离的增加,硬度的变化幅度比较平缓。结论在洛伦兹力作用下,可得到TiB_w/Ti网状结构的复合涂层,电磁复合场使TiB_w/Ti网状结构强化相均匀分布,同时提高涂层的显微硬度。

关键词：激光熔覆洛伦兹力网状结构 TiB 电磁复合场显微组织

Ferrofluid nucleus phase transitions in an external uniform magnetic field

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Chinese Physics B 2015年第10期24卷 322-330页

作者： B.M.Tanygin S.I.Shulyma V.F.kovalenko M.V.Petrychuk Faculty of Radiophysics Taras Shevchenko National University of Kyiv

The phase transition between a massive dense phase and a diluted superparamagnetic phase has been studied by means of a direct molecular dynamics simulation. The equilibrium structures of the ferrofluid aggregate nucleus are obtained for different values of a temperature and an external magnetic field magnitude. An approximate match of experiment and simulation has been shown for the ferrofluid phase diagram coordinates ＂field-temperature＂. The provided phase coexistence curve has an opposite trend comparing to some of known theoretical results. This contradiction has been discussed. For given experimental parameters, it has been concluded that the present results describe more precisely the transition from linear chains to a dense globes phase. The theoretical concepts which provide the opposite binodal curve dependency trend match other experimental conditions： a diluted ferrofluid, a high particle coating rate, a high temperature,and/or a less particles coupling constant value.

关键词： ferrofluid aggregate phase diagram molecular dynamics

A Mechanism of Solar Variability Effect on Radiative Balance of the Earth Atmosphere

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空间科学学报 2005年第5期25卷 450-459页

作者： G.A.Zherebtsov V.A.kovalenko S.I.Molodykh Institute of Solar-Terrestrial Physics Siberian Branch Russian Academy of Sciences Irkutsk 664033 RussiaInstitute of Solar-Terrestrial Physics Siberian Branch Russian Academy of Sciences Irkutsk 664033 RussiaInstitute of Solar-Terrestrial Physics Siberian Branch Russian Academy of Sciences Irkutsk 664033 Russia

Possible mechanisms of solar-climatic connections, which may be of importance as over short and long time intervals, are discussed. The variations of energetic balance of Earth's climatic system for the last fifty years are estimated. It is ascertained that the disbalance between the flux of solar energy that comes to the Earth and radiates to space is of 0.1% for the last ten years. The suggested mechanism makes it possible to explain not only the observed variation of the enthalpy of the Earth's climatic system for the period 1910-1980, but also the climate anomalies during last thousand years: the climate optimum in 12 century, and"small glacial period" in 16-17 centuries.

关键词：太阳活动地球气候系统宇宙

Synthesis of RE-Ag,Al-RE-doped sol-gel glass and films for solar cells

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Journal of Rare Earths 2009年第4期27卷 671-674页

作者： A.V.Semchenko V.V.Sidsky V.Е.Gaishun D.L.kovalenko W.Strek Francisk Skorina Gomel State University 246019 Sovetskaya st.104 Gomel Belarus Institute of Low Temperature and Structures Research PAN Okolna st.2 Wroclaw Poland

The paper dealt with the study of fluorescence properties of sol-gel systems doped with rate-earth ions and co-doped with silver. The general problem for these types of inorganic phosphors was a very low absorbance in the visible range. Therefore, a sensitizer of luminescence of the rare-earth ions should be selected and used. The sensitizer should possess a good absorbance in the visible range and strong interaction with the rare-earth ions. In this study silver ions were selected as the sensitizer.

关键词： sol-gel method sol-gel glass and film luminescence and its amplification rare-earth ions silver ions energy transfer

Callus Cultures Of Beans Infected With Virus As A Model For Testing Antiviral Compaunds

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Journal of Botanical Research 2019年第2期1卷 19-24页

作者： kovalenko Oleksiy Kyrychenko Angelina kovalenko Olena Zobolotny Institute of Microbiology and Virology NAS of Ukraine Kyiv03143Ukraine

In the work,bean callus raised from a leaves of Bean common mosaic virus infected bean plant was obtained and adapted for the testing of antiviral activity of liposomal glycan-glycolipid *** adspersum glucans and Pseudomonas *** were constituents of liposomal *** has been shown that under the long-term cultivation(up to 3 months)in the presence of a liposomal preparation containing(10-100 mg/l),the virus is eliminated from the *** is evidenced by the absence of 391 bp sequence amplification product established by RT-PCR in the callus tissue,cultured on a medium containing the liposomal *** proposed model system is analogous to plant tumors and has obvious advantages over similar systems in vivo,since the callus growth is controlled and independent of environmental factors.

关键词： Bean common mosaic virus(BCMV) Bean yellow mosaic virus(BYMV) Reverse transcriptase polymerase chain reaction(RT-PCR) Plant tumors Glycans Glycolipids Therapy of virus diseases

Solar Activity and the Climate of Prebaikalia

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空间科学学报 2005年第5期25卷 474-477页

作者： V.A.kovalenko G.A.Zherebtsov S.I.Molodykh Institute of Solar-Terrestrial Physics Siberian Branch Russian Academy of Sciences Irkutsk 664033 RussiaInstitute of Solar-Terrestrial Physics Siberian Branch Russian Academy of Sciences Irkutsk 664033 RussiaInstitute of Solar-Terrestrial Physics Siberian Branch Russian Academy of Sciences Irkutsk 664033 Russia

This paper presents convincing evidence for the reality of manifestations of solar variability in climate characteristics of the Prebaikalia. A numerical estimate is obtained of this influence on ground air temperature. It is shown that the main meaningful variations in air temperature in the region for the period1881-1960 were caused by solar activity. Since the 1960s till the present, with the influence of solar variability continuing, a clear-cut influence of another factor has been observed, the role of which has been steadily increasing, and in the hst decade it has now exceeded the contribution of solar variability. Research results on the variations in hydrological characteristics of Lake Baikal and the Angara river and their connection with solar activity are presented. It is shown that these characteristics are closely correlated with the duration of solar cycles.

关键词：太阳活动气候变化大气 GAT