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Lows of Wear process of the Friction pair “0.45% Carbon Steel—polytetrafluoroethylene” during Sliding from the position of Fracture Mechanics

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World Journal of Mechanics 2019年第5期9卷 95-104页

作者： aleksandr v. Bogdanovich Department of Theoretical and Applied Mechanics Belarusian State University Minsk Belarus

The results of the tests for a friction pair “a cylindrical specimen made of 0.45% carbon steel—a counter specimen-liner made of polytetrafluoroethyleneF4-B” during sliding friction are presented. The test results at different levels of contact load are analyzed using the Archard’s equation and are presented as a friction fatigue curve. The concept of the frictional stress intensity factor during sliding friction is introduced, and an expression that relates the wear rate to this factor and is close in shape to the paris equation in fracture mechanics is proposed.

关键词： Sliding Friction Contact pressure Wear Frictional Stress Intensity Factor polymer

Structure and Thermoelectric properties of nanostructured (Bi, Sb)<sub>2</sub>Te<sub>3</sub>(Review)

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Advances in Materials physics and Chemistry 2013年第2期3卷 119-132页

作者： igor A. Drabkin vladimir v. Karataev vladimir B. Osvenski aleksandr I. Sorokin Gennady I. pivovarov natalie yu. Tabachkova Department of dielectric and semiconductor materials National University of Science and Technology “MISIS” Moscow Russia Department of functional and structural materials Technological Institute of Superhard and New Carbon Materials Troitsk Russia Department of semiconductor materials Giredmet Ltd. Moscow Russia

The investigation of the structure and thermoelectric properties of nanostructured solid solutions (Bi, Sb)2Te3 p-type has been carried out. The samples were obtained by grinding of original compositions in a planetary ball mill and by spark plasma sintering (SpS). Initial powder has an average particle size of 10 - 12 nm according to transmission electron microscopy, and the size of the coherent scattering region (CSR) obtained by X-ray line broadening. During sintering at Ts = 250°C - 400°C, the grain size and CSR increased, which was associated with the processes of recrystallization. The maximum of size distribution of CSR shifts to larger sizes when Ts increases so that no broadening of X-ray lines at Ts = 400°C can take place. At higher Ts, the emergence of new nanograins is observed. The formation of nanograins is conditioned by reducing of quantity of the intrinsic point defects produced in the grinding of the source materials. The study of the electrical conductivity and the Hall effect in a single crystal allows to estimate the mean free path of the holes-L in the single crystal Bi0.5Sb1.5Te3 which at room temperature is 2 - 5 nm (it is much smaller than the dimensions of CSR in the samples). The method for evaluation of L in polycrystalline samples is proposed. At room temperature, L is close to the mean free path in single crystals. Scattering parameter holes in SpS samples obtained from the temperature dependence of the Seebeck coefficient are within the measurement error equal to the parameter of the scattering of holes in a single crystal. The figure of merit ZT of SpS samples as a function of composition and sintering temperature has been investigated. Maximum ZT, equal to 1.05 at room temperature, is obtained for the composition Bi0.4Sb1.6Te3 at Ts = 500°C and a pressure of 50 Mpa. The causes of an apparent increase in thermoelectric efficiency are discussed.

关键词： Solid Solutions (Bi Sb)2Te3 p-Type nanostructure Spark plasma Sintering Conductivity Hall Effect Hole Free path Seebeck Coefficient Thermal Conductivity Figure of Merit

problems of Birds Sex Determination

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natural Science 2014年第15期6卷 1232-1240页

作者： Antonina v. Trukhina aleksandr F. Smirnov Department of Genetics and Biotechnology St. Petersburg State University St. Petersburg Russia

Sex determination system in birds is characterized by a homo-(neognatae) and heteromorphic (paleognatae) sex chromosomes. Heterogametic sex is female (ZZ/ZW system). DMRT1 gene is a gene regarded as a main male sex determining factor in this group of animals. The question remains about the participation of other factors (HEMOGEn, AMH etc.) in appearance of testis, and the role of steroid hormones in formation of ovaries. Complete sex inversion is not typical for species with genotypic sex determination (GSD), although the effect of estrogen metabolites is noted for birds. For birds epigenetic mechanisms of regulation (methylation of DnA and non-coding RnA) have been described for sex controlling genes such as CYp19A1 and DMRT1.

关键词： Bird Sex Determination Epigenetics Dosage Compensation

Resolution and contrast enhancement of laser-scanning multiphoton microscopy using thulium-doped upconversion nanoparticles

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nano Research 2019年第12期12卷 2933-2940页

作者： Alexey B.Kostyuk Artem D.vorotnov Andrey v.Ivanov Arthur B.volovetskiy aleksandr v.Kruglov Lyudmila M.Sencha Liuen Liang Evgenii L.Guryev vladimir A.vodeneev Sergey M.Deyev Yiqing Lu Andrei v.Zvyagin Lobachevsky State University of nizhny novgorod Nizhny Novgorod 603950Russia Center of Biomedical Engineering Institute of Molecular MedicineSechenov UniversityMoscow 119991Russia ARC Centre of Excellence"nanoscale Biophotonics" Department of Physics and AstronomyMacquarie UniversitySydney 2109Australia Institute ofBioorganic Chemistry Russian Academy of SciencesMoscow 117997Russia

High-contrast optical imagi ng is achievable using phosphoresce nt labels to suppress the short-lived background due to the optical backscatterand autofluoresce ***,the long-lived phosphorescence is generally incompatible with high-speed laser-scan ning imaging ***,we show that upc on versi on nan oparticles of structure naYF4:Yb co-doped with 8%Tm(8T-UCnp)in combi nation with a commerciallaser-scanning multiphoton microscopy are uniquely suited for labeling biological systems to acquire high-resolution images with the enhancedcon *** comparison with many phosphoresce nt labels,the 8T-UCnp emission lifetime of-15μs affords rapid image ***-order optical nonlinearity of the 8T-UCnp(n=4,as confirmed experimentally and theoretically)afforded pushing the resolution limitattain able with UCnps to the *** contrast enha nceme nt was achieved by suppressing the backgro und using(i)ban dpassspectral filtering of the narrow emission peak of 8T-UCnp at 455-nm,and(ii)time-gating implemented with a time-correlated single-photon counting system that demonstrated the contrast enhancement of>2.5-fold of polyethyle neimine-coated 8T-UCnps take n up by huma nbreast adeno carcinoma cells *** a result,discrete 8T-UCnp nan oparticles became clearly observable in the freshly excised splee ntissue of laboratory mice 15-min post in trave nous injectio n of an 8T-UCnp *** dem on strated approach paves the way forhigh-contrast,high-resoluti on,and high-speed multiphot on microscopy in challe nging envir onments of i ntense autofluorescence,exogenous staining,and turbidity,as typically occur in intravital imaging.

关键词： upconversion nanoparticles autofluorescence time-gated imaging scanning microscopy time-correlated single photon counting

Choice of conodont Idiognathodus simulator （sensu stricto） as the event marker for the base of the global Gzhelian Stage （Upper pennsylvanian Series, Carboniferous System）

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Episodes 2008年第3期31卷 319-325页

作者： philip H. Heckel aleksandr S. Alekseev James E. Barrick Darwin R. Boardman natalya v. Goreva Tatiana n. Isakova Tamara I. nemyrovska Katsumi Ueno Elisa villa David M. Work Department of Geoscience University of Iowa Iowa City Iowa 52242 USA Department of paleontology Geology Faculty Moscow State University 119992 Moscow Russia Department of Geosciences Texas Tech University Lubbock Texas 79409 USA School of Geology Oklahoma State University Stillwater Oklahoma 74078 USA Geological Institute Russian Academy of Sciences Pyzhevsky per. 7 110017 Moscow Russia Institute of Geological Sciences National Academy of Sciences of Ukraine O. Gonchar Str. 55b 01054 Kiev Ukraine Department of Earth System Science Faculty of Science Fukuoka University Fukuoka 814-0180 Japan Department of Geology University of Oviedo Arias de Velasco s/n 33005 Oviedo Spain Maine State Museum 83 State House Station Augusta Maine 04333 USA

We propose that the level at which the conodont species Idiognathodus simulator （Ellison 1941）（sensu stricto） first appears be selected to mark the base of the Gzhelian Stage, because we believe that this is the optimal level by which this boundary can be correlated. This taxon has a short range and a wide distribution, as shown by correlation of glacial-eustatic cyclothems across the Kasimovian-Gzhelian boundary interval among Midcontinent north America and the Moscow and Donets basins of eastern Europe, based on scale of the cyclothems along with several aspects of biostrati- graphy. Outside of these areas, I. simulator （sensu stricto） is known also from other parts of the U.S., and is reported from the southern Urals and south-central China in its expected position between other widespread taxa. Its first appearance is consistent with the current ammonoid placement of the boundary （first appearance of Shumardites cuyleri）, and it is also compatible with certain aspects of the distribution of Eurasian fusulinid faunas （e.g., lectotype ofRauserites rossicus）.

关键词：牙形石奇颚牙形石属模拟技术岩石学

polyphyletic Origin of Ornamental Goldfish

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Food and nutrition Sciences 2015年第11期6卷 1005-1013页

作者： aleksandr v. podlesnykh vladimir A. Brykov Lubov A. Skurikhina Far Eastern Branch of the Russian Academy of Sciences A. V. Zhirmunsky Institute of Marine Biology Vladivostok Russia School of natural Sciences Far Eastern Federal University Vladivostok Russia

Mitochondrial DnA fragment of cytb was compared in all species Carassius auratus complex and three forms of ornamental goldfish. It is shown that the phylogenetic relationships between complex species correspond to the existing views, based on mtDnA data and geographical distribution. All forms of ornamental goldfish have a monophyletic origin from Chinese goldfish C. auratus auratus. The analysis showed that three nuclear genes (rps7, GH1 and Rh) in the two forms of ornamental goldfish (Oriental twintail goldfish and Chinese Ranchu) were almost identical C. auratus auratus genes, while all three gene in another more simple form of goldfish (common goldfish) were highly homologous to carp Cyprinus carpio nuclear genes. The obtained data suggested that in the history of aquarium goldfish breeding occurred the stage of distant hybridization between goldfish and common carp. Subsequently, the nuclear genomes of some ornamental forms could be enriched by goldfish genes (a relatively recent form as Oriental twintail goldfish and Chinese Ranchu) or common carp genes (the simplest and most ancient forms like common goldfish) as a result of multidirectional breeding and selection of aquarium goldfish various forms.

关键词： Goldfish Common Carp Distant Hybridization mtDnA and nuclear Genes

new classification for septic arthritis of the hand

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World Journal of Orthopedics 2023年第2期14卷 85-89页

作者： konstantin v Lipatov Arthur Asatryan George Melkonyan aleksandr D Kazantcev Ekaterina I Solov’eva Irina v Gorbacheva Alexander S vorotyntsev Andrey Y Emelyanov Department of General Surgery Institute of Clinical Medicine Named After N.V.SklifosovskySechenov First Moscow State Medical University(Sechenov University)Moscow 119021Russia Department of Wound and Wound Infection Surgery State Budgetary Institution“City Clinical Hospital named after S.S.Yudin of Moscow Healthcare Department”Moscow 115446Russia Department of General Surgery Hospital for War Veterans№3Moscow 129336Russia Department of General Surgery I.M.Sechenov First Moscow State Medical UniversityMoscow 119048Russia

The severity of septic arthritis of the hand and the prospects for restoration of joint function are determined by a complex of factors. Among them, the leading role belongs to local changes in tissue structures. This includes the destruction of articular cartilage and bone tissue with the development of osteomyelitis, the involvement of paraarticular soft tissues in the purulent process, and the destruction of the flexor/extensor tendons of the fingers. The currently missing specialized classification of septic arthritis could help in systematizing the diseases, determining treatment tactics, and predicting the results of *** classification of septic arthritis of the hand proposed for discussion is based on the following principle: Joint-Wound-Tendon(Jx Wx Tx);Jx characterizes damage to the osteochondral structures of the joint, Wx is the presence of paraarticular purulent wounds or fistulas, and Tx is destruction of the flexor/extensor tendons of the finger. The classification of the diagnosis makes it possible to assess the nature and severity of damage to the structures of the joint and may also be useful when comparing the results of treatment of septic arthritis of the hand.

关键词： Hand Septic arthritis Classification Osteomyelitis paraarticular wounds

ITO-free silicon-integrated perovskite electrochemical cell for light-emission and light-detection

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Opto-Electronic Advances 2023年第9期6卷 45-58页

作者： Maria Baeva Dmitry Gets Artem polushkin aleksandr vorobyov aleksandr Goltaev vladimir neplokh Alexey Mozharov Dmitry vKrasnikov Albert Gnasibulin Ivan Mukhin Sergey Makarov Alferov University Khlopina 8/3St.Petersburg 194021Russia Department of physics and Engineering ITMO UniversityLomonosova 9St.Petersburg 197101Russia Institute of Automation and Control processes(IACp) Far Eastern Branch of Russian Academy of SciencesUlitsa Radio 5Vladivostok 690041Primorsky KraiRussia peter the Great St.petersburg polytechnic University Polytechnicheskaya 29St.Petersburg 195251Russia Skolkovo Institute of Science and Technology Nobel 3Moscow 121205Russia Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao 266000China.

Halide perovskite light-emitting electrochemical cells are a novel type of the perovskite optoelectronic devices that differs from the perovskite light-emitting diodes by a simple monolayered ***,we develop a perovskite electrochemical cell both for light emission and detection,where the active layer consists of a composite material made of halide perovskite microcrystals,polymer support matrix,and added mobile *** perovskite electrochemical cell of CspbBr3:pEO:LiTFSI composition,emitting light at the wavelength of 523 nm,yields the luminance more than 7000 cd/m2 and electroluminescence efficiency of 4.3 lm/*** device fabricated on a silicon substrate with transparent single-walled carbon nanotube film as a top contact exhibits 40%lower Joule heating compared to the perovskite optoelectronic devices fabricated on conventional ITO/glass ***,the device operates as a photodetector with a sensitivity up to 0.75 A/W,specific detectivity of 8.56×1011 Jones,and linear dynamic range of 48 *** technological potential of such a device is proven by demonstration of 24-pixel indicator display as well as by successful device miniaturization by creation of electroluminescent images with the smallest features less than 50μm.

关键词： composite inorganic halide perovskite silicon single walled carbon nanotubes light-emitting electrochemical cell photodetector indicator display

SYnTHESIS AnD pROpERTIES OF λ~5-pHOSpHInInES AnD λ~5-AZApHOSpHInInES

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SYNTHESIS AND PROPERTIES OF λ~5-PHOSPHININES AND λ~5-AZAPH...