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strain-Rate Dependency of a Unidirectional Filament Wound Composite under Compression

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Computer Modeling in Engineering & sciences 2023年第12期137卷 2149-2161页

作者： stepan Konev Victor A.Eremeyev Hamid M.sedighi leonid Igumnov Anatoly Bragov Aleksandr Konstantinov Ayaulym Kuanyshova Ivan sergeichev skolkovo Institute of science and Technologies Center for Materials TechnologiesMoscowRussia National Research Lobachevsky state University of Nizhny Novgorod Nizhny NovgorodRussia Dipartimento di Ingegneria Civile Ambientale e Architettura(DICAAR)Universitàdegli Studi di CagliariCagliari(CA)Italy Mechanical Engineering Department Faculty of EngineeringShahid Chamran University of AhvazAhvazIran Drilling Center of Excellence and Research Center Shahid Chamran University of AhvazAhvazIran

This article presents the results of experimental studies concerning the dynamic deformation and failure of a unidirectional carbon fiber reinforced plastic(T700/LY113)under *** test samples were manufactured through the filament winding of flat *** establish the strain rate dependencies of the strength and elastic modulus of the material,dynamic tests were carried out using a drop tower,the split Hopkinson Pressure Bar method,and standard static *** samples were loaded both along and perpendicular to the direction of the reinforcing *** applicability of the obtained samples for static and dynamic tests was confirmed through finite elementmodeling and the high-speed imaging of the deformation and failure of samples during *** a result of the conducted experimental studies,static and dynamic stress-strain curves,time dependencies of deformation and the stress and strain rates of the samples during compression were *** on these results,the strain rate dependencies of the strength and elasticity modulus in the strain rate range of 0.001-6001/s are *** is shown that the strain rate significantly affects the strength and deformation characteristics of the unidirectional carbon fiber composites under *** increase in the strain rate by 5 orders of magnitude increased the strength and elastic modulus along the fiber direction by 42%and 50%,*** loading resulted in a strength and elastic modulus increase by 58%and 50%,*** average strength along the fibers at the largest studied strain rate was about *** obtained results can be used to design structural elements made of polymer composite materials operating under dynamic shock loads,as well as to build models of mechanical behavior and failure criteria of such materials,taking into account the strain rate effects.

关键词： High strain rate composites filament winding dynamic strength split Hopkinson Pressure Bar compression

Biomarkers of Lipid status and Metabolism in Retinal Hypertensive Disorder

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Journal of Biosciences and Medicines 2021年第4期9卷 77-89页

作者： Ecaterina Pavlovschi Djina Borovic Valeriana Pantea leonid Lîsîi Olga Tagadiuc Department of Biochemistry and Clinical Biochemistry Nicolae Testemitanu State University of Medicine and Pharmacy Chi&scedil in&abreve u Republic of Moldova Ovisus Medical Private Center Chi&scedil in&abreve u Republic of Moldova Laboratory of Biochemistry Nicolae Testemitanu State University of Medicine and Pharmacy Chi&scedil in&abreve u Republic of Moldova

Background. Hypertension (HTN) is a preventable risk factor for morbidity and mortality worldwide. Hypertensive retinopathy (HR), its ocular complication, is characterized by progressive metabolic disorders and structural damage of the retina. Lipids play an essential role in retina homeostasis, so an alteration of lipid metabolism specific for HTN may be of great significance in the development of hypertensive retinal injury. The study aimed to investigate the association between HR, traditional lipid biomarkers changes, and the atherogenic index, as well as to highlight a possible role of lipid metabolism markers in HR diagnosis and prognosis. span> Methods. A total of 90 hypertensive patients from the Republic of Moldova, admitted to the Ovisus Medical Center, Chisinau, Republic of Moldova, for a vision check and firstly diagnosed with HR were recruited in our study.span> The enrolment period is between February 2018 and December 2019. They were divided into three groups based on fundoscopy, using Keith-Wagner-Barker grading system of HR—GI: 36 patients;GII: 35 patients;GIII: 19 patients. The level of serum lipids: triglycerides, total cholesterol, LDL-Chol, and HDL-Chol was determined, followed by the calculation of the atherogenic index of plasma. Results are displayed as the median and interquartile range (IQR). Kolmogorov-Smirnovspan> and shapiro-Wilk normality tests were used, followed by Levene’s homogeneity of variance test. The groups were compared using the non-parametric Kruskal-Wallis and Mann-Whitney tests. The spearman correlation coefficient was calculated (sPss 23.0)sp

关键词： TAG Total Cholesterol LDL-Chol HDL-Chol Hypertensive Retinopathy

A Variation Account of Divergent Thinking

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Journal of Literature and Art studies 2017年第8期7卷 1039-1053页

作者： leonid Dorfman Vera Gassimova Perm state Institute of Culture Perm Russia

A variation account was applied to divergent thinking accommodated as a kind of creative thinking. To provide control （contrast） condition the variation account was applied to psychometric intelligence. Guilford＇s （1956, 1967, 1988） theory of divergent-----convergent thinking served the background of our study. The main premise was that creative variation represents ＂thought trials＂ with diverse ways to find a solution to the problem. Task demands and the respective creative problem solving reveal advantageous sources that suggest the variation. Probably, uncertainty, information search, and finding alternatives extracted from memory precede, entail and provide variety of seeking, as well. A principal hypothesis to be tested was that divergent thinking enables its variation rather than intelligence does that to its variation. As predicted, the divergent thinking and its variation were related. Compared to uncreative, creative persons were characterized by larger variation. Apart from the mathematical intelligence, other kinds of intelligence and their variation did not correlate. Mainly, the data obtained, thus, lend support to the claimed hypothesis.

关键词： variation creativity divergent thinking intelligence scattering

“snake”: New Object of Hypothetical Venusian Fauna

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International Journal of Astronomy and Astrophysics 2014年第1期4卷 29-38页

作者： leonid V. Ksanfomality space Research Institute of the Russian Academy of sciences Moscow Russia

On March 1 and 5, 1982, experiments in television photography instrumented by the landers VENERA-13 and 14 returned panoramas of the Venus surface at the landing site. Over the past 31 years, no similar missions have been sent to Venus. In connection with the renewed interest in what was occurring during the experiment and to the discovery of manifestations of possible life revealed on some of the pictures, the panoramas were re-examined.?Analysis of treated once again VENERA-14 panoramic images revealed a?“snake”?object about 40 cm in size possessing apparent terramorphic features. The snake’s body stands out with its honeycomb, spotty surface against the stone plates close by. The “snake”?can be included into the list of the most significant findings of the hypothetical Venusian fauna. Apart from that, of interest is a?“dove”?object, although details of its structure cannot be discerned. The snake’s body show slow movements, which is another evidence of the Venusian fauna’s very slow style of activity, which appears to be associated with its energy constraints, and that is more likely, with the properties of its internal medium. The terramorphic features of the fauna, if they are confirmed, may point out outstandingly important and yet undiscovered general laws of the animated nature.

关键词： Planet Venus’ Fauna Astrobiology space Vehicles Instruments Planet’s surface

Impact of Climate and Grazing on Biomass Components of Eastern Russia Typical steppe

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Journal of Integrative Agriculture 2014年第6期13卷 1183-1192页

作者： Ubugunov leonid Rupyshev Yuriy Ubugunov Vasiliy HOU Xiang-yang Vishnyakova Oxana Lavrentieva Irina Ubugunova Vera REN Wei-bo DING Yong Institute of General and Experimental Biology Siberian Branch of Russian Academy of Sciences Grassland Research Institute Chinese Academy of Agricultural Sciences

spatial and structural characteristics of plant communities in the steppe ecosystems of the Baikal region, Russian Federation have been researched in connection with climate change and grazing. The present study, based on a total of 15 typical steppe sampling plots, investigated above-ground biomass （AGB）, below-ground biomass （BGB）, total biomass （TB） and root：shoot ratios （R：s） and their relationships with climatic factors and grazing. All biomass components varied widely depending on the climatic parameters and the degree of grazing affected transformation. A strong negative correlation between mean annual temperature （MAT） and total plant biomass was revealed for all study area. Mean annual precipitation （MAP） signiifcantly affected communities productivity increasing only in the south of the region. Due to the large and mountainous territory, the inlfuence of latitude and elevation （mountain） factors on the components of the biomass were studied. Although all studied plant steppe communities were transformed by uncontrolled grazing, their productivity is signiifcantly reduced only at plots with maximum digression. Vegetation shift is an indicator of climate change, as well as providing a diagnostic tool to build predictive models. Based on the complex index of effective precipitation, it was revealed that at the end of last century in the steppes of the Baikal region the structural and production processes will be affected by an arid climate trend.

关键词： steppe productivity climate grazing transformation Baikal region

The Cherenkov Radiation in the Galaxy’s Halo of Dark Matter

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International Journal of Astronomy and Astrophysics 2013年第3期3卷 285-290页

作者： leonid M. Chechin V. G. Fessenkov Astrophysical Institute Almaty Kamenskoye Plato National Centre for the Space Researches and Technology National Space Agency Republic of Kazakhstan

The effect of light refraction in a galaxy’s halo of dark matter, described by profiles of Navarro-Frenk-White and Burkert, was considered. Powers of the Cherenkov radiation for the refractive indexes of gravitational fields with these profiles were calculated. It was shown that correspondent radiation temperature in the X-rays diapason have the magnitude about T^10-6K . It was also marked that its detection may be the criteria on choosing the preferable dark matter density distribution in a galaxy.

关键词： Dark Matter Profile The Cherenkov Radiation

Quantum Gravity in Heisenberg Representation and self-Consistent Theory of Gravitons in Macroscopic spacetime

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Journal of Modern Physics 2013年第2期4卷 285-297页

作者： Grigory Vereshkov leonid Marochnik Physics Department University of Maryland East West Space Science Center College Park USA Research Institute of Physics Southern Federal University Rostov-on-Don Russia

The first mathematically consistent exact equations of quantum gravity in the Heisenberg representation and Hamilton gauge are obtained. It is shown that the path integral over the canonical variables in the Hamilton gauge is mathematically equivalent to the operator equations of quantum theory of gravity with canonical rules of quantization of the gravitational and ghost fields. In its operator formulation, the theory can be used to calculate the graviton s-matrix as well as to describe the quantum evolution of macroscopic system of gravitons in the non-stationary Universe or in the vicinity of relativistic objects. In the s-matrix case, the standard results are obtained. For problems of the second type, the original Heisenberg equations of quantum gravity are converted to a self-consistent system of equations for the metric of the macroscopic space time and Heisenberg operators of quantum fields. It is shown that conditions of the compatibility and internal consistency of this system of equations are performed without restrictions on the amplitude and wavelength of gravitons and ghosts. The status of ghost fields in the various formulations of quantum theory of gravity is discussed.

关键词： Quantum Gravity

H. Cohen and E. Cassirer: the Foundations of Kant'sEthics

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H. Cohen and E. Cassirer: the Foundations of Kant'sEthics

Two-Component substance Basing the Direction Dependence of the Cosmological Deceleration Parameter

作者： leonid Tetyuev saratov state University

The subject for analysis in this article is the foundations of Kant's ethics in the Neo-Kantian philosophy of the Marburg school. This article draws the parallel between the ethics of H. Cohen and P. Natorp. In contrast to E. Cassirer's teachers, who defined ethics as an important part of philosophy, Cassirer did not write a separate work on ethics. Cassirer turns to Kant's ethics not only with the purpose of revealing the special features of his own critical method, but mostly because he tries to reconstruct its original philosophical principles: the concept of autonomy, the concept of freedom and individual personality, which became the starting point for the system of ethical idealism. The boundary between the personal cognition and world conception lies between being and oughtness, the necessary and the possible. We can find the motives of Cassirer's critical position in the late period of his creative work, when the philosopher reveals the transcendental history of the moral consciousness in "The Myth of the state".

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International Journal of Astronomy and Astrophysics 2012年第4期2卷 195-198页

作者： leonid M. Chechin V. G. Fessenkov Astrophysical Institute Almaty Kazakhstan

*** description of Hubble’s diagrams asymmetry of and calculating the anisotropy of the deceleration parameter phenomenon, that was recently found by R.-*** and Z.-***. For doing this the concepts of Universe rotation and its two-component model were *** result is in good correlation (case of the upper magnitude index) with the value that was got in [1].significance. The result of article gives new basing of the Universe rotation axis existence.

关键词： Anisotropy of the Deceleration Parameter Universe Principal Axis