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Nuclear Science and Techniques 2016年第1期27卷 21-28页

作者： vladimir Zaichick Sofia Zaichick Radionuclide Diagnostics Department Medical Radiological Research Centre Department of Medicine University of Illinois College of Medicine at Chicago

A nondestructive instrumental neutron activation analysis with high-resolution gamma-ray spectrometry of long-lived radionuclides was developed and used for measurement of trace element contents in samples of bone to determine health and diseases. Using this method, the silver(Ag), cobalt(Co), chromium(Cr), iron(Fe), mercury(Hg), rubidium(Rb), antimony(Sb), selenium(Se), and zinc(Zn) mass fractions were estimated in bone samples from 27 patients with intact bone(12 females and 15 males, aged from 16 to 49 years) who had died from various non-bone-related causes, mainly unexpected traumas,and from 5 patients with chondroma(2 females and 3males, 15–42 years old), obtained from open biopsies or after operation. The reliability of the differences in the results between intact bone and bone affected by chondroma was evaluated by a parametric Student's t test and a nonparametric Mann–Whitney U test. It was found that in the bone affected by chondroma, the mean mass fractions of Co, Cr, Fe, Se, Sb, and Zn were significantly higher than in normal bone tissues. In the neoplastic bone, many correlations between trace elements found in the control group were no longer evident. This work revealed that there is asignificant disturbance of the trace element metabolism in bone affected by chondroma.

关键词：微量元素含量高分辨率中子活化长寿命 γ能谱法活化产物样品测定

Technological lubricating means： Evolution of materials and ideas

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Frontiers of Mechanical Engineering 2016年第1期11卷 101-107页

作者： vladimir A. GODLEVSKIY Department of Physics Ivanovo State University Ivanovo 153025Russia

The main stages of technological lubricating material development from ancient times to date are described. How the chemical composition of these products changed with time, how new ideas revealing the physical and chemical basics of external media that influence the mechanical processing of materials appeared, how these ideas explained the differences between traditional tribology and specific technology of metal processing are discussed. The question of the possible realization of Rehbinder＇s adsorption effect in contact zone is also stated. The description of a very captivating problem is related to the explanation of the mechanism of lubricant penetration into the contact zone between the material being processed and the tool. The birth and development of the hypothesis of microcapillary penetra- tion of the lubricant into the dynamically changed intersurface clearance that has finally led to formulating the ＂necessary kinetic condition of the lubricating activity＂ is relayed.

关键词： technological lubrication and cooling metal cutting grinding lubrication action tribology

Effect of Y_2O_3 and Total Oxide Addition on Mechanical Properties of Pressureless Sintered β-SiC

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Journal of Materials Science & Technology 2003年第3期19卷 193-196页

作者： vladimir D.Krstic Centre for Manufacturing of Advanced Ceramics and Nanomaterials Queen’s UniversityNicol HallKingstonOntarioCanada K7L 3N6

The effect of Y203 and the total oxide volume fraction (Y203+AI203) on density and mechanical properties of low temperature (1770-1940℃) pressureless sintered β-SiC ceramics were presented. The optimum temperature for pressureless sintering of β-SiC was found to be -1850℃ and the optimum content of Y203 in the oxides was found to be between 40 and 57 wt pct. The highest sintered density was achieved by adding oxides at 14 vol. pct. Both of the highest strength and fracture toughness were achieved at -14 vol. pct oxide addition and yttria concentrations between 40 and 57 wt pct in the oxides. Hardness, on the other hand, was found to be the highest for samples with 14 vol. pct oxide addition and -64 wt pct Y2O3 in oxides.

关键词： Y_2O_3 SiC Mechanical properties Sintering

Elaboration of a conceptual solution for the development of the Arctic shelf from seasonally flooded coastal areas

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International Journal of Mining Science and Technology 2022年第1期32卷 113-119页

作者： vladimir S.Litvinenko Mikhail V.Dvoynikov vladimir L.Trushko Saint-Petersburg Mining University Saint-Petersburg 199106Russia

Currently,construction of facilities in the Arctic is carried out on sand islands,but there are limitations for remote coastal *** restrictions are associated with the lack of quarries with construction sand in the immediate vicinity of the work site,as well as the risk of seasonal flooding of the *** article includes conceptual solutions for construction of modular piling in Arctic nearshore conditions,upon which drilling rigs and auxiliary equipment can be placed for the purpose of subsequent wildcatting,development and exploratory extended reach drilling wells(with measured depth about 15000 m).During the construction of the modular piling foundations,a mathematical simulation of the thermodynamic condition of the frozen ground was conducted,and the bearing capacity of the foundations was *** proposed solutions will solve these problems by constructing modular pile foundations and placing the necessary infrastructure on them,taking into account the distribution of loads during operation in seasonally flooded areas.

关键词： Drilling&drillholes Stress analysis Offshore engineering Infrastructure planning Geotechnical engineering Extended reach drilling

A theory to link relationships of stand volume,density,mean diameter and height in forestry data

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Journal of Forestry Research 2021年第1期32卷 15-20页

作者： vladimir L.Gavrikov Chair of Ecology and Environmental Studies Institute Ecology and GeographySiberian Federal University79 pr.SvobodnyiKrasnoyarskRussian Federation 660041

In this study,a geometric model of a growing forest stand has been *** basic relationships considered link stand volume and stand density,diameter at breast height(DBH),mean DBH and mean *** model provides simple formulas connecting the exponents of all the *** of the formulas to real forestry data provided a high level of predictions of an exponent from two others measured through regressions from empirical *** Pinus sylvestris *** were of a static nature,a collection of individual stands,while the Pseudotsuga menziesii(Mirb.)Franco data were dynamic,representing forest stand development over *** ability of the model to predict exponents in the empirical data implies,on the one hand,a substantial level of similarity between the model and the forestry ***,on the other hand,the model gives an example in which parameters of one relationship may be linked to parameters of *** this kind of‘relationship between relationships’may be observed in forest stands undergoing active growth and competition-induced self-thinning.

关键词： Relationship between relationships Selfthinning Forestry data Allometry Scots pine Douglasfir

Impact of normal stress-induced closure on laboratory-scale solute transport in a natural rock fracture

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第4期12卷 732-741页

作者： Liangchao Zou vladimir Cvetkovic Division of Resources Energy and InfrastructureDepartment of Sustainable DevelopmentEnvironmental Science and EngineeringRoyal Institute of TechnologyStockholm10044Sweden Department of Physical Geography Stockholm UniversityStockholm10691Sweden

The impact of normal stress-induced closure on fluid flow and solute transport in a single rock fracture is demonstrated in this *** fracture is created from a measured surface of a granite rock *** Bandis model is used to calculate the fracture closure due to normal stress,and the fluid flow is simulated by solving the Reynold *** Lagrangian particle tracking method is applied to modeling the advective transport in the *** results show that the normal stress significantly affects fluid flow and solute transport in rock *** causes fracture closure and creates asperity contact areas,which significantly reduces the effective hydraulic aperture and enhances flow ***,the reduced aperture and enhanced channeling affect travel time *** particular,the enhanced channeling results in enhanced first arriving and tailing behaviors for solute *** fracture normal stiffness correlates linearly with the 5th and 95th percentiles of the normalized travel *** finding from this study may help to better understand the stress-dependent solute transport processes in natural rock fractures.

关键词： Normal stress Fluid flow Solute transport Stiffness Particle tracking

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冰岛东部最美小镇白日梦想家们的隐世仙境

环球人文地理 2024年第13期 144-153页

作者：邓文倩 vladimir marieagns Nataliya Fotokon Sen Isabel Baldovi Marc Jedamus Kristina Ryan Unsplash 摄图网

冰岛东部峡湾，有一个小镇被群山、瀑布环绕，远离城市喧嚣，宛如被时间遗忘的世外桃源。在电影《白日梦想家》中，男主角沃尔特为了找到杂志新刊的底片，踏上了一段奇幻冒险旅程。他在影片里看似穿越了格陵兰岛、冰岛、尼泊尔、喜马拉...

冰岛东部峡湾，有一个小镇被群山、瀑布环绕，远离城市喧嚣，宛如被时间遗忘的世外桃源。在电影《白日梦想家》中，男主角沃尔特为了找到杂志新刊的底片，踏上了一段奇幻冒险旅程。他在影片里看似穿越了格陵兰岛、冰岛、尼泊尔、喜马拉雅山脉……但实际上整部电影的取景地全都在冰岛。影片最令人印象深刻的部分，大概是沃尔特用公仔和小孩子交换滑板后，在一条盘山公路上急速滑行。公路的尽头就是被LonelyPlanet评为“冰岛东部最美小镇”的塞济斯菲厄泽。

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On finite 2-groups all of whose subgroups are mutually isomorphic

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Science China Mathematics 2009年第2期52卷 254-260页

作者： EPULIC vladimir Faculty of Electrical Engineering and Computing University of Zagreb

In this paper we investigate the title groups which we call isomaximal. We give the list of all isomaximal 2-groups with abelian maximal subgroups. Further, we prove some properties of isomaximal 2-groups with nonabelian maximal subgroups. After that, we investigate the structure of isomaximal groups of order less than 64. Finally, in Theorem 14. we show that the minimal nonmetacyclic group of order 32 possesses a unique isomaximal extension of order 64.

关键词： p-groups maximal subgroups minimal nonabelian minimal nonmetacyclic 20D15

用于创建数据库和分析冬季运动项目运动员训练信息的技术——以北欧两项为例

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北京体育大学学报 2024年第2期47卷 149-153页

作者：弗拉基米尔·泽布泽耶夫崔明坤(译) 柴可夫斯基国立体育学院俄罗斯柴可夫斯基617740 北京体育大学教育学院中国北京100084

现代体育的显著特点是竞争异常激烈。运动员为了取得最高成绩,往往会进行超负荷的训练[1-3]。运动训练的效率主要取决于对运动员状态信息进行收集、系统化和存储的质量。为了达到这些目的,近年来人们开始使用数据库,它可以将信息存储在... 详细信息

现代体育的显著特点是竞争异常激烈。运动员为了取得最高成绩,往往会进行超负荷的训练[1-3]。运动训练的效率主要取决于对运动员状态信息进行收集、系统化和存储的质量。为了达到这些目的,近年来人们开始使用数据库,它可以将信息存储在计算机系统中,而不是零散地存储在纸质或电子媒介中。如此一来,就可以大大提高决策的效率,这在运动员训练和竞技过程中不断产生大量信息流的情况下尤为重要。

关键词：信息存储现代体育计算机系统运动员训练数据库电子媒介信息流冬季运动项目

Powerful terahertz waves from long-wavelength infrared laser filaments

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Light(Science & Applications) 2020年第1期9卷 204-219页

作者： vladimir Yu.Fedorov Stelios Tzortzakis Science Program Texas A&M University at QatarP.O.Box 23874DohaQatar P.N.Lebedev Physical Institute of the Russian Academy of Sciences 53 Leninskiy ProspektMoscow 119991Russia Institute of Electronic Structure and Laser(IESL) Foundation for Research and Technology-Hellas(FORTH)P.O.Box 1527Heraklion GR-71110Greece Department of Materials Science and Technology University of CreteHeraklion GR-71003Greece

Strong terahertz(THz)electric and magnetic transients open up new horizons in science and *** review the most promising way of achieving sub-cycle THz pulses with extreme field *** the nonlinear propagation of two-color mid-infrared and far-infrared ultrashort laser pulses,long,and thick plasma strings are produced,where strong photocurrents result in intense THz *** corresponding THz electric and magnetic field strengths can potentially reach the gigavolt per centimeter and kilotesla levels,*** intensities of these THz fields enable extreme nonlinear optics and relativistic *** offer a comprehensive review,starting from the microscopic physical processes of light-matter interactions with mid-infrared and far-infrared ultrashort laser pulses,the theoretical and numerical advances in the nonlinear propagation of these laser fields,and the most important experimental demonstrations to date.

关键词： laser extreme optics