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Selection of shaped charges parameters for producing aluminum particles with velocities in the range of 2.5-16 km/s

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Defence Technology（防务技术） 2024年第8期38卷 126-135页

作者： vladimir I.Kolpakov Sergey V.fedorov Ekaterina P.Vinogradova Irina A.Bolotina Bauman Moscow State Technical University Moscow 105005Russia

Testing rocket and space technology objects in ground conditions for resistance to the impact of meteoroids and fragments of space debris can be carried out using shaped charges. To substantiate the design parameters of shaped charges that ensure the formation of aluminum particles in a wide velocity range(from 2.5 to 16 km/s), numerical modeling of the formation process was carried out within the framework of a two-dimensional axisymmetric problem of continuum mechanics using three different computing codes to increase the reliability of the results. The calculations consider shaped charges with a diameter of 20-100 mm with aluminum liners of various shapes. It is shown that the formation of particles with velocities close to the lower limit of the considered range is ensured by gently sloping segmental liners of degressive thickness. To form higher-velocity particles with velocities over 5 km/s, it is proposed to use combined liners, the jet-forming part of which has the shape of a hemisphere of constant thickness or the shape of a semi-ellipsoid or semi-superellipsoid of rotation of degressive thickness.

关键词： Space debris Meteoric impact Explosion Shaped charge High-velocity aluminum element Segmental liner Combined liner Numerical simulation

Measurement of yields and angular distributions ofγ-quanta from the interaction of 14.1 MeV neutrons with oxygen,phosphorus,and sulfur

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Chinese Physics C 2024年第3期48卷 79-92页

作者： D.N.Grozdanov N.A.fedorov S.B.Dabylova yu.N.Kopatch I.N.Ruskov V.R.Skoy T.yu.Tretyakova C.Hramco P.I.Kharlamov G.V.Pampushik P.G.Filonchik A.V.Andreev Joint Institute for Nuclear Research(JINR) DubnaRussia Institute for Nuclear Research and Nuclear Energy Bulgarian Academy of SciencesSofiaBulgaria Faculty of Physics Lomonosov Moscow State UniversityMoscowRussia L.N.Gumilyov Eurasian National University AstanaKazakhstan Skobeltsyn Institute of Nuclear Physics Moscow State UniversityMoscowRussia Institute of Chemistry of Moldova ChisinauRepublic of Moldova Moscow Institute of Physics and Technology MoscowRussia

A study of the inelastic scattering of neutrons with an energy of 14.1 MeV on the nuclei of oxygen,phosphorus,and sulfur was performed at the TANGRA facility at JINR(Dubna).The experiment aimed to refine existing data and obtain new data on the yields and angular distributions ofγ-quanta emitted by the studied nuclei due to neutron-induced nuclear reactions using the tagged neutron *** types of detector systems were used to registerγ-***γ-ray yields were measured using a high-purity germanium(HPGe)*** angular distributions ofγ-rays were obtained using a system of 18 scintillation detectors based on bismuth germanite Bi_(4)Ge_(3)O_(12)(BGO)located around the *** performed experiments measured the yields of two transitions for the reaction of tagged neutrons with 16O,nine transitions for the reaction with ^(31)P,and nine transitions for the reaction with ^(32)S for the first *** angular anisotropy of theγ-radiation accompanying the inelastic scattering of neutrons with an energy of 14.1 MeV on ^(31)P nuclei was also measured for the first time.

关键词： tagged neutron method yields of gamma-quanta high-resolution gamma-spectrometry neutron-nuclear reactions neutron scattering

树轮记录的阿尔泰山南坡过去304年夏季温度变化及水热配置模式

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第四纪研究 2024年第4期44卷 859-868页

作者：李强刘禹 Olga Solomina 王嘉川 vladimir Matskovsky 宋慧明孙长峰庞文轩闫亚兰蔡秋芳任萌程海全球环境变化研究院西安交通大学陕西西安710049 黄土与第四纪地质国家重点实验室中国科学院地球环境研究所陕西西安710061 Institute of Geography Russian Academy of SciencesMoscow 119017Russia 西安地球环境创新研究院陕西西安710061

阿尔泰山南坡受到西风急流、北冰洋冷湿气流、蒙古-西伯利亚高压和亚洲低压共同影响,形成了当地特有的气候模式;同时,阿尔泰山地区是欧亚沟通的枢纽地带,气候变化对周边人类生产生活以及生态系统影响显著。因此有必要了解阿尔泰山周边... 详细信息

阿尔泰山南坡受到西风急流、北冰洋冷湿气流、蒙古-西伯利亚高压和亚洲低压共同影响,形成了当地特有的气候模式;同时,阿尔泰山地区是欧亚沟通的枢纽地带,气候变化对周边人类生产生活以及生态系统影响显著。因此有必要了解阿尔泰山周边气候变化长期历史,识别气候变化特征,总结规律以应对未来气候变化带来的灾害。本研究利用相关分析发现阿尔泰山南坡西伯利亚落叶松树轮宽度年表与夏季(6~7月)温度呈显著关系(r=0.626,n=58,p<0.001),进而建立一阶线性回归模型方程定量重建了阿尔泰山南坡过去304年(1715~2018年)夏季温度变化。统计结果显示重建序列稳定可靠,并有能力代表大范围的温度变化特征。重建存在5个暖期(1740~1767年、1775~1793年、1837~1847年、1898~1909年、1990~2018年)和5个冷期(1715~1727年、1807~1828年、1848~1858年、1876~1897年、1927~1940年)。虽然自1990年来温度持续上升(1990~2018年温度距平0.33℃),但并未超过1740~1767年的温度(温度距平0.49℃)。结合周边降水重建序列,发现研究区域在过去3个多世纪表现出夏季水热同步的配置模式,即暖湿/冷干模态占主导地位。

关键词：温度重建树轮宽度阿尔泰山西伯利亚落叶松

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围立体定向放射治疗期使用生长抑素类似物对生长激素腺瘤患者放疗疗效的影响研究进展

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国际内分泌代谢杂志 2024年第4期44卷 250-254页

作者： vladimir Melnikov 俞一飞何敏张朝云李益明复旦大学附属华山医院内分泌科上海200040

术后放射治疗可使60%~70%的肢端肥大症患者达到生化缓解,但起效缓慢,从治疗起效到生化缓解需要27.5~43.0个月的时间。立体定向放射治疗是目前常用的放疗类型,该疗法采用精准且高剂量的电离辐射照射生长激素腺瘤,相比普通放疗,可以使患... 详细信息

术后放射治疗可使60%~70%的肢端肥大症患者达到生化缓解,但起效缓慢,从治疗起效到生化缓解需要27.5~43.0个月的时间。立体定向放射治疗是目前常用的放疗类型,该疗法采用精准且高剂量的电离辐射照射生长激素腺瘤,相比普通放疗,可以使患者更快地达到生化缓解。由于放疗的起效时间比较长,为更好的控制生化水平,有临床指南推荐接受放疗的患者在放疗前接受生长抑素类似物治疗,并在放疗后使用生长抑素类似物作为过渡治疗。但目前对于围放疗期使用生长抑素类似物对肢端肥大症患者的生化缓解是否有影响存在争议,需要进一步探索,并确认围放疗期是否需要使用生长抑素类似物治疗以及使用的时间窗。

关键词：肢端肥大症生长激素腺瘤生长抑素类似物立体定向放射治疗

Rare earth elements(REE)and isotope composition(δ^(13)C andδ^(18)O)of manganese ores of Chiatura deposit(Georgia):features of ore formation and genesis

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Acta Geochimica 2023年第4期42卷 779-801页

作者： vladimir N.Kuleshov Andrey yu.Bychkov Irina yu.Nikolaeva Maria E.Tarnopolskaya Geological Institute Russian Academy of SciencesPyzhevskii Per.7MoscowRussia 119017 Lomonosov Moscow State University Leninskie Gory1MoscowRussia 119899

The rare earth elements(REE)geochemistry and the isotope(δ^(13)C,δ^(18)O)composition of manganese ores of the Chiatura(Georgia)deposit were *** of the major features of all types of manganese ores is negative cerium(Ce/Ce*_(PAAS))anomaly and the absence of europium(Eu/Eu*_(PAAS))*** oolitic manganese ores were formed in oxic shallow marine *** content and distribution of REEs(in particular Ce and Eu)in these ores are connected mainly with ferrous *** performed C-and O-isotope research in Mn-carbonates(oolitic and massive)has indicated that carbonate ores were formed by the participation of isotopic ally light CO_(2)which is a result of the oxidation of organic matter in the sediment strata by reducing environments of early diagenesis(and,partially,catagenesis)*** negative cerium anomalies in the studied carbonate ores reflect the specific REE patterns in pore waters of sediments of earlier isdiagenesis zone of the Oligocene Chiatura's *** deficiency of cerium in this zone remains debatable and requires further *** of manganese carbonates took place multistage by the input of incisional solutions of different chemistry into sea bottom waters and *** absence of europium anomaly indicates about lack of hydrothermal solution input.

关键词： REE Cerium anomaly Carbon and oxygen isotope geochemistry Oxide and carbonate manganese ores Chiatura deposit

Reduced Recombination Current Due to Sputtered CdO Nanolayer at CdS/CdTe Interface

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Materials Sciences and Applications 2023年第3期14卷 186-207页

作者： Amjad Al-Qassem vladimir fedorov Ludmila Gagara Tamara Potlog Physics Department and Engineering Moldova State University Chisinau Republic of Moldova Institute of Electronic Engineering and Nanotechnologies Chisinau Republic of Moldova

In this paper, interface engineering via sputtering of CdO nanolayer at the buffer-CdS/CdTe-absorber interface is demonstrated as an efficient approach to improve the performance of solar cell device. The i-CdO interfacial layer with various thicknesses from 5 nm to 35 nm was deposited by DC magnetron sputtering. Comparative studies on TCO/CdS/CdTe and TCO/CdS/CdO/CdTe interfaces have been conducted by current-voltage, capacitance-voltage and admittance spectroscopy measurements. The current-voltage characteristics of the devices with an area of 0.45 cm2 under 100 mW/cm2 illumination, at the optimum thickness of CdO intermediate layer in the proposed structures, show increases of the short circuit current density and the open circuit voltage by 5% and 25%, respectively. The efficiency improvement of 3.1% of p-i-n cell over p-n cell is observed. Results of the temperature-dependent current-voltage and admittance measurements revealed the removing of the deep level defect with the activation energy of 0.43 eV and the reducing of the ideality factor from 1.9 to 1.8 via buffer/absorber interfacial passivation method. Interface passivation appears to be critical to improve the short circuit current density and the open circuit voltage, and CdO thin film is clearly effective for this purpose.

关键词： CdS/CdTe Photovoltaic Devices CdO Interface Engineering Defects

Flotation separation of wolframite from calcite using a new trisiloxane surfactant as collector

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International Journal of Mining Science and Technology 2023年第3期33卷 379-387页

作者： Shuyi Shuai Zhiqiang Huang vladimir E.Burov vladimir Z.Poilov Fangxu Li Hongling Wang Rukuan Liu Shiyong Zhang Chen Cheng Wenyuan Li Xinyang yu Guichun He Weng Fu Jiangxi Province Key Laboratory of Mining Engineering Jiangxi University of Science and TechnologyGanzhou 341000China Department of Chemical Engineering Perm National Research Polytechnic UniversityPerm 614990Russia Guangdong Institute of Resources Comprehensive Utilization Guangzhou 510650China Hunan Academy of Forestry Changsha 410004China School of Chemical Engineering University of QueenslandSt Lucia 4072 QLDAustralia

Since wolframite is usually associated with calcite,the separation and enrichment of wolframite by froth flotation remains a great ***,a novel trisiloxane surfactant N-(2-aminoethyl)-3-ami nopropyltrisiloxane(AATS)was successful synthesized,which was used for the separation of wolframite from calcite for the first *** flotation separation performance of AATS was studied by flotation test,and its adsorption mechanism was explored based on contact angle,infrared spectrum analysis(FTIR),zeta potential and density functional theory(DFT)*** results of microflotation test and binary mixed ore flotation test pointed that AATS had excellent selectivity and more prominent collection capacity for the flotation of wolframite when compared with industrial reagent sodium oleate(NaOL).The measurement results of contact angle proved that AATS improved the hydrophobicity of the wolframite *** highly selective adsorption mechanism of AATS surfactant on mineral surfaces were further researched and analyzed by FTIR and zeta *** results revealed that AATS surfactant had significant adsorption effect on wolframite,yet almost no adsorption on *** calculation indicated that AATS produced electrostatic adsorption with wolframite surface through—N+H3 group.

关键词： Flotation Wolframite Calcite Trisiloxane surfactant Adsorption

Magnetoelectric coupling at microwave frequencies observed in bismuth ferrite-based multiferroics at room temperature

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Journal of Materials Science & Technology 2023年第6期137卷 100-103页

作者： Man Zhang vladimir Koval yu Shi Yajun yue Chenglong Jia Jiagang Wu Giuseppe Viola Haixue Yan School of Engineering and Materials Science Queen Mary University of LondonMile End RoadLondon E14NSUK Institute of Materials Research Slovak Academy of SciencesWatsonova 47Kosice 04001Slovakia Key Laboratory for Magnetism and Magnetic Materials of MOE Lanzhou UniversityLanzhou 730000China Department of Chemistry Queen Mary University of LondonMile End RoadLondon E14NSUK Department of Materials Science Sichuan UniversityChengdu 610064China

***,In the search for advanced multifunctional materials for next generation sensors and logic devices,magnetoelectric multifer-roics exhibiting simultaneously ferromagnetism and ferroelectric-ity within the same phas... 详细信息

关键词： microwave coupling ferroelectric

Ignition of nanothermites by a laser diode pulse

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Defence Technology（防务技术） 2022年第2期18卷 194-204页

作者： Alexander yu.Dolgoborodov vladimir G.Kirilenko Michael A.Brazhnikov Leonid I.Grishin Michael L.Kuskov Georgii E.Valyano Joint Institute for High Temperatures Russian Academy of SciencesRussia N.Semenov Federal Research Center for Chemical Physics Russian Academy of SciencesRussia National Research Nuclear University MEPhI Moscow Russia

Experimental investigation has been carried out for laser ignition and combustion of nanothermites based on aluminum and oxides of copper,bismuth and *** mixing of nanosized powders was used to produce *** thermite ignition,initiating laser pulse with a maximum intensity of 770 W/cm2 was generated by a laser diode with a wavelength of 808 *** ignition delay times,the minimum initiation energy density,and the average burning rate at various thermite densities and mass fractions of components were determined by recording the emission of radiation of the reaction products using a multichannel pyrometer jointly with a high-speed video *** effect of adding carbon black on the threshold parameters of a laser pulse was also *** on the obtained results,certain assumptions were put forward with regard to the mechanism of nanothermites’ignition by laser radiation and their *** particular,the assumptions were made on the two-stage process of the reaction initiation and jet burning mechanism of porous nanothermites.

关键词： Nanothermites Laser ignition Burning rate Ignition delay