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Pulsed THz radiation under ultrafast optical discharge of vacuum photodiode

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Frontiers of Optoelectronics 2024年第2期 100-113页

作者： Aleksandr A.Ushakov Kseniia A.Mamaeva Leonid v.seleznev Georgy E.Rizaev vladimir Bukin Timophey v.Dolmatov Pavel A.Chizhov vladimir Bagdasarov Sergey v.Garnov Prokhorov General Physics Institute of the Russian Academy of Sciences Physical Institute Russian Academy of Sciences Moscow Institute of Physics and Technology Russian Institute for Scientific and Technical Information

In this paper, we first present an experimental demonstration of terahertz radiation pulse generation with energy up to 5 pJ under the electron emission during ultrafast optical discharge of a vacuum photodiode. We use a femtosecond optical excitation of metallic copper photocathode for the generation of ultrashort electron bunch and up to 45 kv/cm external electric field for the photo-emitted electron acceleration. Measurements of terahertz pulses energy as a function of emitted charge density, incidence angle of optical radiation and applied electric field have been provided. Spectral and polarization characteristics of generated terahertz pulses have also been studied. The proposed semi-analytical model and simulations in COMSOL Multiphysics prove the experimental data and allow for the optimization of experimental conditions aimed at flexible control of radiation parameters.

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Numerical forecasting surge in a piping of compressor shops of gas pipeline network

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第11期8卷 1775-1788页

作者： seleznev v. E. PRYALOv S. N. Physical & Technical Center Joint Stock Company Sarov 607180 Russia

This paper presents a method of forecasting stable operation of gas compressor unit (GCU) centrifugal supercharger (CFS) installed on a piping of compressor shops servicing gas pipelines. The stability of superchargers operation is assessed in relation to the phenomenon of surge. Solution of this problem amounts to the development and numerical analysis of a set of ordinary differential equations. The set describes transmission of gas through a compressor shop as a fluid dynamics model with lumped parameters. The proposed method is oriented to wide application by specialists working in the gas industry. The practical application of this method can use all-purpose programming and mathematical software available to specialists of gas companies.

关键词： Gas pipelines Compressor station Centrifugal supercharger (CFS) Surge Numerical simulation

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Transparent and Biocompatible Electrodes Based on Carbon Nanotubes/Albumin Composite

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Open Journal of Composite Materials 2013年第2期3卷 33-39页

作者： Dmitry Kireev Ivan I. Bobrinetskiy Alexey S. seleznev Igor v. Fedorov Alexey v. Romashkin Roman A. Morozov Center for Probe Microscopy and Nanotechnology National Research University of Electronic Technology Moscow Russia.

We describe a new method for transparent and conductive films based on carbon nanotubes and bovine serum albumin composite development. Films are deposited from an aqueous solution of carbon nanotubes/bovine serum albumin by drop-coating and rod-coating methods. Sheet resistances of as-prepared films vary from 200 Ohm/sq with 50% transmittance to 30 KOhm/sq with 90% transmittance. The maximum sdc/sop ration found in this work is 2.27, which gives a DC conductivity of 4.55 × 104 S·m-1. Atomic force microscopy and Raman spectroscopy studies of the films show that the process of film formation produces neither structural nor chemical changes in the nanotubes. Possibility of using these films for cell culturing is tested on human embryonic fibroblast cell line. Therefore, it is first time ever in literature, when proposed a method, allowing fabricating at the same time transparent, high-conductive and biocompatible CNT films.

关键词： Carbon Nanotubes Transparent Electrodes Biocompatible Composite

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介电频散测井在油页岩储层评价中的应用

国外测井技术 2011年第6期31卷 69-75页

作者： Nikita v．seleznev 赵平周利军（译）丁柱（校）大庆测井公司大庆燃气公司

众所周知,油页岩资源丰富,粗略估计有三万亿桶。如果成功开采,这种极具潜力的可开采资源可成为长期的可供油源。确定油母含量是油页岩开采评价和经济地描绘可开采层段的主要任务之一。由于GreenRiver地层含有淡水,所以根据电阻率测井曲... 详细信息

众所周知,油页岩资源丰富,粗略估计有三万亿桶。如果成功开采,这种极具潜力的可开采资源可成为长期的可供油源。确定油母含量是油页岩开采评价和经济地描绘可开采层段的主要任务之一。由于GreenRiver地层含有淡水,所以根据电阻率测井曲线确定油母含量变得复杂了。介电频散测井提供了以地层水和其它地层成分(矿产和油母)的介电常数的差异为基础的另外一种法。介电测井可以提供含水孔隙度和地层水矿化度,综合其它测井方法,能够评价地层油母含量。GreenRiver浅层沉积含有淡水,可能与含淡水的近地表相连,这些淡水可作为饮用水。要求经营者保护淡水水层以免受较深地层采油气或盐水的污染。为了保护淡水资源,有必要识别井眼穿过的淡水地层,然后监测矿化度和油气含量。介电测井可完成这些任务,它是快速可靠的环境监测方法。用新一代介电频散测井仪测量GreenRiver地层,该仪器可提供多种频率下的地层介电常数和电导率。准确解释介电测量结果需要输入岩石骨架介电常数。本文给出了干燥岩石和粉末的介电常数实验室测量方法,该方法可用于对GreenRiver地层岩样的分析(根据原文这样翻译,但好像不符合逻辑)。对同一组样品,我们也得到了其矿物和化学特性以及模拟核测井响应。对岩石骨架介电常数和测井参数之间的相关性进行了分析对比。然后,利用介电测井和其它测井对地层水含量、地层矿化度和油母含量给出解释,并且与一口邻井的岩心测量结果做比较。

关键词：电阻率测井曲线介电常数储层评价油页岩频散地层水矿化度环境监测方法淡水资源

高强化柴油机活塞裙部固体润滑剂涂层的抗摩擦性能评价

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汽车与新动力 2021年第4期4卷 62-66页

作者： [俄]K.v.GAvRILOv [俄]A.v.MOROZOv [俄]M.v.seleznev [俄]Y.v.ROZHDESTvENSKII [俄]N.A.KHOZENIUK [俄]A.A.DOIKIN [俄]v.S.HUDYAKOv 刘涛(译) 不详

比较了固体润滑涂层在高强化内燃机活塞裙-缸套耦合中降低摩擦和提高抗拉伤的耐摩擦性能。以高纯硫化钼和石墨为基础的聚合物粘结剂制成的各种改性涂层沉积于零件表面,并以石墨基涂层作为参考样品,成功地应用于重型车辆柴油机的钢活塞... 详细信息

比较了固体润滑涂层在高强化内燃机活塞裙-缸套耦合中降低摩擦和提高抗拉伤的耐摩擦性能。以高纯硫化钼和石墨为基础的聚合物粘结剂制成的各种改性涂层沉积于零件表面,并以石墨基涂层作为参考样品,成功地应用于重型车辆柴油机的钢活塞上。该研究在摩擦温度为110℃、正常负荷为50~450 N、往复频率为20.0 Hz的条件下进行,这与柴油机摩擦电偶的运行条件相似。分析结果表明,沉积的所有涂层显著降低了摩擦系数,在同时含有二硫化钼和石墨的有些涂层,其摩擦系数可降至0.12~0.14,符合在润滑材料存在或不存在直接金属接触的2种摩擦状态下摩擦表面的接触条件。

关键词：固体润滑涂层拉伤磨损活塞裙部石墨脂钼脂

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