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Frontiers of physics 2015年第3期10卷 65-82页

作者： Dingping Li Baruch Rosenstein B. ya. Shapiro I. Shapiro School of Physics Peking University Beijing 100871 China Collaborative Innovation Center of Quantum Matter Beijing 100084 China Electrophysics Department National Chiao Tung University Hsinchu 30050 Taiwan China physics Department Ariel University Ariel 40700 Israel Physics Department Bar-Ilan University 52900 Ramat-Gan Israel

New two-dimensional systems such as the surfaces of topological insulators （TIs） and graphene offer the possibility of experimentally investigating situations considered exotic just a decade ago. These situations include the quantum phase transition of the chiral type in electronic systems with a relativistic spectrum. Phonon-mediated （conventional） pairing in the Dirac semimetal appearing on the surface of a TI causes a transition into a chiral superconducting state, and exciton condensation in these gapless systems has long been envisioned in the physics of narrow-band semiconductors. Starting from the microscopic Dirac Hamiltonian with local attraction or repulsion, the Bardeen- Cooper-Schrieffer type of Gaussian approximation is developed in the framework of functional integrals. It is shown that owing to an ultrarelativistic dispersion relation, there is a quantum critical point governing the zero-temperature transition to a superconducting state or the exciton condensed state. Quantum transitions having critical exponents differ greatly from conventional ones and belong to the chiral universality class. We discuss the application of these results to recent experiments in which surface superconductivity was found in TIs and estimate the feasibility of phonon pairing.

关键词： topological insulator Weyl semimetal superconductivity quantum criticality

The Iwasava decomposition and intermediate subgroups of the Steinberg groups over the field of fractions of a principal ideal ring

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Science China Mathematics 2009年第2期52卷 318-322页

作者： MOISEENKOVA T. V. NUZHIN ya. N. Institute of Fundamental Development Siberian Federal University St. Kirenskogo 26Krasnoyarsk 660074Russia

Abstract The Iwasava decomposition is proved for the Steinberg groups of types 2 A 2l?1, 2 D l , 2 E 6, 3 D 4 over the field of fractions of a principal ideal ring. By using this decomposition, it is described that su... 详细信息

关键词： principal ideal ring Steinberg group intermediate subgroups 20G25

Medium effects in ΛK~＋ pair production by 2.83 GeV protons on nuclei

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Chinese Physics C 2017年第12期41卷 88-105页

作者： E. ya. Paryev M. Hartmann Yu. T. Kiselev Institute for Nuclear Research Russian Academy of Sciences Moscow 117312 Russia Institute for Theoretical and Experimental Physics Moscow 117218 Russia Institut für Kernphysik and Jülich Centre for Hadron Physics Forschungszentrum Jiilich D-52425 Jiilich Germany

We study ΛK~＋ pair production in the interaction of protons of 2.83 GeV kinetic energy with C, Cu,Ag, and Au target nuclei in the framework of the nuclear spectral function approach for incoherent primary proton–nucleon and secondary pion–nucleon production processes, and processes associated with the creation of intermediate Σ~0K~＋ pairs. The approach accounts for the initial proton and final Λ hyperon absorption, final K~＋ meson distortion in nuclei, target nucleon binding, and Fermi motion, as well as nuclear mean-field potential effects on these *** calculate the Λ momentum dependence of the absolute ΛK~＋ yield from the target nuclei considered, in the kinematical conditions of the ANKE experiment, performed at COSY, within the different scenarios for the Λ-nucleus effective scalar potential. We show that the above observable is appreciably sensitive to this potential in the low-momentum region. Therefore, direct comparison of the results of our calculations with the data from the ANKE-at-COSY experiment can help to determine the above potential at finite momenta. We also demonstrate that the two-step pion–nucleon production channels dominate in the low-momentum ΛK~＋ production in the chosen kinematics and, therefore, they have to be taken into account in the analysis of these data.

关键词： proton-nucleus reactions medium effects hyperon nuclear potential

The Effect of Super Volcanic Eruptions on Ozone Depletion in a Chemistry–Climate Model

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Advances in Atmospheric Sciences 2019年第8期36卷 823-836页

作者： Luya.g XU Ke WEI Xue WU S. P. SMYSHLya.V Wen CHEN V. ya. GALIN Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100190China Russian State Hydrometeorological University Malookhtinskii pr.98St.Petersburg 195196Russia Institute of Numerical Mathematics Russian Academy of Sciencesul.Gubkina 8Moscow 11999Russia

With the gradual yet unequivocal phasing out of ozone depleting substances(ODSs), the environmental crisis caused by the discovery of an ozone hole over the Antarctic has lessened in severity and a promising recovery of the ozone layer is predicted in this century. However, strong volcanic activity can also cause ozone depletion that might be severe enough to threaten the existence of life on Earth. In this study, a transport model and a coupled chemistry–climate model were used to simulate the impacts of super volcanoes on ozone depletion. The volcanic eruptions in the experiments were the 1991 Mount Pinatubo eruption and a 100 × Pinatubo size eruption. The results show that the percentage of global mean total column ozone depletion in the 2050 RCP8.5 100 × Pinatubo scenario is approximately 6% compared to two years before the eruption and 6.4% in tropics. An identical simulation, 100 × Pinatubo eruption only with natural source ODSs, produces an ozone depletion of 2.5% compared to two years before the eruption, and with 4.4% loss in the tropics. Based on the model results,the reduced ODSs and stratospheric cooling lighten the ozone depletion after super volcanic eruption.

关键词： stratospheric ozone volcanic eruptions stratospheric aerosols chemistry–climate model

Results of Thirty Years of Research on Corals and Reefs of Vietnam

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Open Journal of Marine Science 2016年第2期6卷 283-292页

作者： Yuri ya. Latypov A.V. Zhirmunsky Institute of Marine Biology Far East Branch Russian Academy of Sciences Vladivostok Russia

The author traced the history of the thirty years of study of the Vietnamese reefs since the second half of the 20th century up to the present time. This paper describes the types of reefs, taxonomic composition and structure of Scleractinian reef ecosystems. It is shown that due to a high level of diverse knowledge revealed, high species richness of coral fauna of Vietnam (376 species of 80 genera) is a single point of origin coral fauna Indo-Pacific. Analysis of knowledge of Vietnamese corals and reefs revealed the extent of their positive or negative status under anthropogenic influence or under the level of wilderness protection, experiment on artificial cultivation of corals and the re-establishment of a coral community.

关键词： Scleractinia Coral Communities Species Richness Vietnam

The Bivalve Mollusc <i>Abra ovata</i>: Role in Succession of Soft Bottom Communities on Newly Flooded Area of the Caspian Sea

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American Journal of Climate Change 2015年第3期4卷 239-247页

作者： Yuri ya. Latypov A.V. Zhirmunsky Institute of Marine Biology Far East Branch Russian Academy of Sciences Vladivostok Russia

The succession of an Abra ovata community that had formed at the flooded area in Sulaksky Bay (the Caspian Sea) since the mid-1980s was investigated. The resident species Abra ovata and Cerastoderma glaucum, the pioneer settlers, were found remaining dominant in the community structure and driving the course of its succession, despite some decrease in settlement density and in the rate of occurrence. It was the tolerance of the Sulaksky pioneer settlers for later colonists (macrophytes, mytilids, crustaceans and other organisms) that determined the development of the first succession stage. The next succession stage in Abra ovata communities of Sulaksky Bay does not quite agree with the pattern typical of solid substrates. On the one hand, the community development supports the tolerance model: the pioneer Abra, in spite of being dominant through all the succession stages, does not oppose the settling of other multiple colonists;on the other hand, it agrees with a facilitation model where the abundance of the original settlers, the grazing species, provokes appearance of sturgeon.

关键词： Caspian Sea Flooded Area Succession Bottom Community Bivalve Mollusc Abra ovata

The Composition and Structure of Reef Community at Tho Chu Island (South China Sea) after Ketsana Typhoon

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American Journal of Climate Change 2013年第4期2卷 284-291页

作者： Yuri ya. Latypov A.V. Zhirmunsky Institute of Marine Biology Far East Branch of Russian Academy of Sciences (FEB RAS) Vladivostok Russia

Fringing the reefs of the island Tho Chu explored a quarter century later now reexamined in the Gulf of Thailand of the South China Sea. It was found that most of the reefs of the island were lost after the passage of typhoon “Ketsana” accompanied by heavy rains and strong sea waves higher than 2 meters in October 2009. Because of these natural phenomena, physical destruction of much of the coral communities occurred. Removal of terrigenous sediments from the islands in the water has led to increased sedimentation and loss of almost all the scleractinian family Acroporidae, the main building corals on the reefs of the Indo-Pacific. At present, in places where once there was full-reef community succession is restoring the reef due to the survivors of the typhoon colonies of coral genera Pocillopora and Acropora.

关键词： Typhoon Ketsana Destruction Reef Community Change Succession Vietnam

Viscosity of Nanofluids. Why It Is Not Described by the Classical Theories

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Advances in Nanoparticles 2013年第3期2卷 266-279页

作者： Valery ya. Rudya. Department of Theoretical Mechanics Novosibirsk State University of Architecture and Civil Engineering Novosibirsk Russian Federation

Transport properties of nanofluids are extensively studied last decade. This has been motivated by the use of nanosized systems in various applications. The viscosity of nanofluids is of great significance as the application of nanofluids is always associated with their flow. However, despite the fairly large amount of available experimental information, there is a lack of systematic data on this issue and experimental results are often contradictory. The purpose of this review is to identify the typical parameters determining the viscosity of nanofluids. The dependence of the nanofluid viscosity on the particles concentration, their size and temperature is analyzed. It is explained why the viscosity of nanofluid does not described by the classical theories. It was shown that size of nanoparticles is the key characteristics of nanofluids. In addition the nanofluid is more structural liquid than the base one.

关键词： Nanofluids Gas Nanosuspensions Nanoparticles Viscosity Kinetic Theory Molecular Dynamics Rheology of Nanofluids Effect of Nanoparticles Size

On Solvability of an Inverse Boundary Value Problem for a Fourth Order Elliptic Equation

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Journal of Mathematics and System Science 2013年第11期3卷 560-566页

作者： ya. T.Mehraliyev Department of differential and inteqral equations Baku State University Khalilov 23 Baku AZ1148 Azerbaijan

In the paper an inverse boundary value problem for a fourth order elliptic equation with an integral condition of the first kind is investigated. First, the given problem is reduced to an equivalent problem in a certain sense. Then, using the Fourier method the equivalent problem is reduced to solving the system of integral equations. The existence and uniqueness of a solution to the system of integral equation is proved by the contraction mapping principle. This solution is also the unique solution to the equivalent problem. Finally, by equivalence, the theorem of existence and uniqueness of a classical solution to the given problem is proved.

关键词： Inverse boundary value problem elliptic equation Fourier method classical solution.

A New Method of Measurement of the True Temperature and Emissivity of Non-Black Body Using One Component of Wien’s Spectrum of Thermal Radiation

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Journal of Applied Mathematics and Physics 2015年第5期3卷 524-529页

作者： D. ya. Svet Joint Institute for High Temperatures of the Russian Academy of Sciences Moscow Russian Federation

It is shown that the measurement of only one component of the Wein’s spectrum of thermal radiation in range λT ≤ 3000 (°C μm) is sufficient to estimate the true temperature and spectral emissivity of the selected component with sufficient accuracy, although more than one hundred years this statement was considered as incorrect. The proposed method is based on the formation of the linear dependence of the logarithm of the emissivity of not real wavelengths and artificially generated “virtual” spectral components.

关键词： True Temperature Spectral Emissivity Wein’s Law