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Ordered exponential and its features in Yang-Mills effective action

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Communications in Theoretical Physics 2023年第8期75卷 119-127页

作者： A v Iv.n.v.n.v Kharuk St.Petersburg Department of Steklov Mathematical Institute of Russian Academy of Sciences 27 FontankaSt.Petersburg 191023Russia Leonhard Euler International Mathematical Institute 10 Pesochnaya nab.St.Petersburg 197022Russia

In this paper,we discuss some non-trivial relations for ordered exponentials on smooth Riemannian *** an example of application,we study the dependence of the four-dimensional quantum Yang–Mills effective action on the special gauge transformation with respect to the background ***,we formulate some open questions about a structure of divergences for a special type of regularization in the presence of the background field formalism.

关键词： Yang-Mills effective action ordered exponential heat kernel Green's function short-distance asymptotics cutoff regularization Synge's world function

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中亚和哈萨克斯坦的民众伊斯兰教

世界民族 1989年第1期 41-47页

作者： v.n.巴西洛夫方园

宗教和生活世界宗教的历史表明,宗教教谕向其信徒们灌输的各种思想并非都付诸实践。人们只从宗教的教谕中抽取出那些与他们的看法相一致的观点,那些在一种已经建立起来的生活方式的范围之内可行的行为准则。当然,随着时间的推移,许多情... 详细信息

宗教和生活世界宗教的历史表明,宗教教谕向其信徒们灌输的各种思想并非都付诸实践。人们只从宗教的教谕中抽取出那些与他们的看法相一致的观点,那些在一种已经建立起来的生活方式的范围之内可行的行为准则。当然,随着时间的推移,许多情况发生了变化,民众的意识接受了原先与其格格不入的思想。但是,这一原则依然不变:如果某些教义不符合人们的需要,他们就会想法回避或代之以其他教义,即那些在一定的时间里能满足社会需求的教义。

关键词：伊斯兰教哈萨克斯坦穆斯林教生活方式宗教思想萨满教苏菲派圣人治病仪式妇女

Performance Analysis of Thermoacoustic Refrigerator of 10 W Cooling Power Made up of Poly-v.n.l-Chloride for Different Parallel Plate Stacks by Using Helium as a Working Fluid

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Journal of Thermal Science 2021年第6期30卷 2037-2055页

作者： n v Shivakumara BHEEMSHA Arya Department of Mechanical Engineering BMS College of EngineeringBengaluru 560019India Department of Mechanical Engineering Government PolytechnicChannasandraBengaluru 560067India

Refrigerants are usually provided in the conv.n.ional refrigeration system although the refrigerants produce Chlorofluorocarbons(CFCs)and Hydro-chlorofluorocarbons(HCFCs),which are hazardous to the ***,these disadv.n.ages can be overcome by using air or inert gas in the thermoacoustic refrigeration *** the present experimental work,helium is used as a working gas with an operating pressure range of 0.2 MPa to 1.0 MPa in order to study the performance of thermoacoustic refrigerator(TAR)which is fabricated using Poly-v.n.l-Chloride(PvC).The parallel plate stacks with different porosity ratios have been considered to study the performance of *** temperature difference between the hot and cold heat exchanger and acoustic dynamic pressure were recorded by using Bruel and Kjaer data acquisition system under different operating *** effect of different operating parameters such as operating frequency(200 Hz to 600 Hz),cooling load(2 W to 10 W)and drive ratio(0.6%to 1.6%)have also been considered to study the performance of *** TAR also modeled in DeltaEC software and the results are compared with the experimental outcomes and found to be in good *** experimental results show that-2.1℃is the lowest temperature measured at cold heat exchanger by achiev.n. the highest temperature difference of about 32.9℃.An improvement is around 36%as compared to that of previous experiments that used aluminium *** highest Coefficient of Performance(COP)and the Relative Coefficient of Performance(COPR)are found to be 2.024 and 0.217,respectively.

关键词： thermoacoustic refrigerator parallel plate stack porosity ratio temperature difference COP COPR

Gate-Dependent nonlinear Hall Effect at Room Temperature in Topological Semimetal GeTe

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Chinese Physics Letters 2023年第7期40卷 63-67页

作者： n.n.Orlova A.v.Timonina n.n.Kolesnikov E.v.Deviatov Institute of Solid State Physics of the Russian Academy of Sciences ChernogolovkaMoscow District2 Academician Ossipyan str.142432Russia

We experimentally investigate nonlinear Hall effect as zero-frequency and second-harmonic transverse voltage responses to ac electric current for topological semimetal GeTe.A thick single-crystal GeTe flake is placed on the Si/SiO_(2) substrate,where the p-doped Si layer serves as a gate *** confirm that electron concentration is not gate-sensitive in thick GeTe flakes due to the gate field screening by bulk *** contrast,by transverse voltage measurements,we demonstrate that the nonlinear Hall effect shows pronounced dependence on the gate electric field at room *** the nonlinear Hall effect is a direct consequence of a Berry curvature dipole in topological media,our observations indicate that Berry curvature can be controlled by the gate electric *** experimental observation can be understood as a result of the known dependence of giant Rashba splitting on the external electric field in *** possible applications,the zero-frequency gate-controlled nonlinear Hall effect can be used for the efficient broad-band rectification.

关键词： temperature. field. curvature

Evaluation of the energy efficiency of rotary percussive drilling using dimensionless energy index

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第5期14卷 1486-1500页

作者： v.n.Oparin v.n.Karpov v.v.Timonin A.I.Konurin Chinakal Institute of Mining Siberian BranchRussian Academy of SciencesKrasnyi Prospect 54Novosibirsk630091Russia

This paper sets forth a geomechanics framework for assessing the energy efficiency of rotary percussive drilling using the energy criterion, which has been proposed by victor Oparin for volumetric destruction of high-stress rocks hav.n. nonuniform physico-mechanical properties. We review the long-term research and development in the specified area of science and technology, including research and development projects implemented at the Institute of Mining, Siberian Branch of the Russian Academy of Sciences. A new modified expression of Oparin’s dimensionless energy criterion of volumetric rock destruction k is introduced. The range of in situ values is determined for the energy criterion of volumetric rock destruction at the optimized energy efficiency of rotary percussive drilling. The temporospatial intervals of geotechnical monitoring are found to control pneumatic drilling energy efficiency at subsoil use objects in Russia. The integrated experimental, theoretical and geotechnical approach to the comprehensive investigation of real-time processes of rock fracture in rotary percussive drilling using the energy concept possesses the necessary geomechanical performance-and-technology potential to create the next level geotechnical monitoring of drilling systems for various purposes, including determination of physico-mechanical properties and the stress-strain analysis of rock mass in full-scale drilling.

关键词： Rotary percussive drilling Geotechnical monitoring Drilling machine Energy criterion Energy efficiency

Synthesis of MoO_3 by glow discharge in contact with water

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Plasma Science and Technology 2019年第2期21卷 97-104页

作者： A v KHLYUSTOvA n A SIROTKIn A S KRAYEv v A TITOv A v AGAFOnOv Laboratory of Chemistry of Carbohydrate Coordination Compounds and Supermolecular System G.A.Krestov Institute of Solution Chemistry of RAS

An atmospheric pressure glow discharge was ignited between a molybdenum anode and the water surface of a cathode for the synthesis of MoO_3 powders. The action of glow discharge leads to the non-equilibrium evaporation of water, sputtering of the metal anode and formation of molybdenum(vI) oxide, which deposited on the anode. The chemical composition and morphology of the obtained powder were performed by using x-ray diffraction spectroscopy,scanning electron microscopy and Fourier transform infrared spectroscopy. It was found that the synthesized powders are pure α-MoO_3. The possible mechanism of the formation of molybdenum trioxide during glow discharge treatment was described. The photocatalytic performance of MoO_3 was estimated through the degradation of Rhodamine B under dark and Uv irradiation conditions. Orthorhombic MoO_3 exhibited the best photocatalytic activity for the photodegradation of Rhodamine B of 100% under Uv irradiation for 15 min.

关键词： molybdenum oxide glow discharge photocatalytic activity

Sexual Reproduction One Billion Years Ago

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natural Resources 2013年第5期4卷 383-386页

作者： Petr n. kolosov Diamond and Precious Metal Geology Institute Siberian Branch Russian Academy of Sciences Yakutsk Russia

The facts regarding to the early stages of algae evolution in the Precambrian are very rare (more than 542 million years ago). In this paper, the author describes the first discovered evidence that the sexual reproduction process took place one billion years ago. As it is known, sexual reproduction led to the diversity of liv.n. organisms on the Earth, and in general, accelerated the evolution process.

关键词： Microorganisms Cyanobacteria Algae Cells Sexual Reproduction Evolution neoproterozoic Siberia

The Role of Red Algae in Abrupt Appearance of Animals in the Early Cambrian on Siberian Platform

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American Journal of Plant Sciences 2013年第12期4卷 60-64页

作者： P. n. kolosov Diamond and Recious Metal Geology Institute SB RAS Yakutsk Russia

Calcified rock-forming marine filamented benthic micro- and macrophytes of Dzhelindia kolosov, 1970 (Figure 1(а)) and Chaptchaica kolosov, 1975 (Figure 1(b)) genera, thrived in neoproterozoic (1000-541 million years ago) Siberia together with cyanobacteria. Their belonging to Rhodophyta is well-grounded. These and other neoproterozoic rodofits, as well as Epiphyton Bornemann 1886 (Figure 1(c)) and other Early Cambrian (541-513 million years ago) benthic algae, oxygenating floor of epicontinental sea basin, formed conditions, favorable for the animals. In combination with other biotic, and such abiotic factors as: equatorial position and tectonic feature of Siberian platform;volcanism;transgression of the sea;diversity of ecologic niches, these conditions were prerequisites of skeleton and shell acquisition by Early Cambrian animals, and as a consequence, accelerated morphologic evolution, increased diversity of taxons of different groups of animals.

关键词： Cyanobacteria Rhodophyta Symbios Skeleton Biodiversity neoproterozoic Cambrian Siberian

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多孔介质中天然气水合物生成的主要影响因素

天然气工业 2017年第5期37卷 38-45页

作者： Khlebnikov v.n. Antonov S.v. Mishin A.S. 梁萌 Khamidullina I.v. Zobov P.M. Likhacheva n.v Gushchin P.A. 俄罗斯古勃金国立石油天然气大学

目前有关天然气水合物(以下简称水合物)的研究主要集中在物理化学性质考察和开采(分解)方法探索方面。在进行后者的研究过程中,地层渗流过程的物理模拟至关重要,但目前借助于石油开采研究中广泛应用的填砂管等多孔介质对水合物进行动态... 详细信息

目前有关天然气水合物(以下简称水合物)的研究主要集中在物理化学性质考察和开采(分解)方法探索方面。在进行后者的研究过程中,地层渗流过程的物理模拟至关重要,但目前借助于石油开采研究中广泛应用的填砂管等多孔介质对水合物进行动态过程的研究却鲜有报道。为此,利用河砂填砂管在岩心驱替装置上进行了甲烷水合物生成过程的物理模拟,考察了地层温度、甲烷压力及地层模型性质参数等对水合物生成过程的影响。结果表明:(1)利用冰融水作为地层模型的束缚水可显著提升甲烷水合物的生成速率;(2)多孔介质条件下过程驱动力(即实验压力或温度偏离水合物相平衡对应值的程度)对甲烷水合物的生成起着决定性作用;(3)当甲烷压力高于水合物相平衡压力1.4倍以上,或者实验温度低于相平衡温度3℃以下时,甲烷水合物生成诱导期几乎不随温压条件的变化而变化;(4)渗透率、含水饱和度、润湿性等参数对实验中甲烷水合物的生成率不构成明显影响。

关键词：甲烷水合物多孔介质生成过程天然气水合物地层物理模拟影响因素诱导期生成率