检索结果-南通市图书馆

Study of the e^+e^- to hadrons via ISR at BABAR

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2010年第6期34卷 660-668页

作者： E.P.Solodov Budker Institute of Nuclear Physics

Experimental data from the PEP-II B-factory at 10.6 GeV center-of-mass （c.m.） energy, obtained via initial-state radiation （ISR） with the BABAR detector, are presented. The cross sections for many hadronic processes have been measured from the production threshold to 4-5 GeV of the e^＋e^- c.m. energy. The obtained data allow to study a number of intermediate states and determine the parameters of known resonances and their branching fractions. The exclusive cross section for some number of hadronic sub-processes are presented.

关键词： ISR e^+e^- hadrons BABAR

Processing stages of Gd_2Sr(Al_(1-x)Fe_x)_2O_7 series

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2014年第1期33卷 47-53页

作者： Ekaterina Tugova Victor Gusarov Laboratory of New Inorganic Materials Ioffe Physical Technical Institute of RAS Department of Physical Chemistry St. Petersburg State Institute of Technology Technical University

The continuous series of perovskite-related oxides with the general formula GdzSr（Al1-xFex）207 0 〈 x 〈 1 were prepared by conventional ceramic technology in air. The pro- cessing stages of Gd2Sr（Al1-xFex）207 0 〈 x 〈 1 phases were investigated by means of X-ray powder diffraction （XRD） and scanning electron microscopy （SEM） with the element phase analysis. The three main stages of GdeSr（All_~Fex）aO7 for- marion are pointed out. The analysis of the mutual influence of intermediate compounds on the synthesis of the target solid solutions of complex composition, in particular for Gd2Sr（All-xFex）207 was carried out. It is determined that the closeness of the reactive mixture composition to the composition of individual compounds Gd2SrA1207 or GdaSrFeaO7 is of importance for the realization of a partic- ular way of GdESr（Al1-xFex）207 solid solutions formation. It is shown that at x ,= 0.2 the reversing in scheme of Gd2Sr（Al1-Fex）207 series formation is observed. The formation of the Gd2Sr（Al1-xFex）207 continuous series is indicated by the monotonic dependence of molar unit cell volume on the iron content x.

关键词： Rare-earth metals Oxide materials Solid-state reactions Ceramics X-ray diffraction (XRD) Scanning electron microscopy (SEM)

Application of thermally stimulated acoustic emission method to assess the thermal resistance and related properties of coals

在线全文

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2018年第2期28卷 243-249页

作者： E.A.Novikov R.O.Oshkin V.L.Shkuratnik S.A.Epshtein N.N.Dobryakova National University of Science and Technology(MISiS) Moscow 119049Russia

Traditional methods of coal thermal resistance characterization are informative but considerably timeconsuming and require utilization of a complex and expensive equipment. This limits the effectiveness of their application. In this paper, authors experimentally investigated potential application of thermally stimulated acoustic emission method for developing of relatively simple and rapid coals thermal resistance assessment method. Features of thermally stimulated acoustic emission of anthracite, lignites and bituminous coal samples subject to cyclic thermal loading have been experimentally *** the first time, it has been shown that there exists a relationship of such patterns with structural parameters and properties of the coal samples, as well as their thermal resistance. The results indicate the possibility of applying the method of thermally stimulated acoustic emission to control processes of cryogenic disintegration and thermal resistance of fossil coals. The description of the equipment and methodological support needed for the implementation of this method have been provided.

关键词： Acoustic emission Fossil coal Thermal resistance Cryogenic disintegration Structure Properties

Migration of organic carbon and trace elements in the system glacier-soil in the Central Caucasus alpine environment

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2022年第12期19卷 3458-3474页

作者： Ivan KUSHNOV Evgeny ABAKUMOV Rustam TEMBOTOV Timur NIZAMUTDINOV Saint Petersburg State University 7/9 University EmbankmentSt Petersburg199034Russia Tembotov Institute of Ecology of Mountain Territories of russian Academy of Sciences 7a I.Armand StreetNalchik360051Russia

Rapid deglaciation is one of the most important challenges in the Earth science *** reason of this is specific supraglacial sediments–cryoconites,which represent carbon-containing dust with organomineral matter and living *** of physical and chemical characteristics of cryoconites in the Central Caucasus is necessary in order to understand their influence on alpine territories biogeochemical cycles,pollution and development in conditions of intensive glacial melting and active anthropogenic *** this research cryoconites as well as moraines,soil-like bodies and soils have been sampled from the alpine Bezengi Glacier and adjacent Khulamo-Bezengi *** physicochemical features(pH values,total organic carbon content,microbial respiration,particle-size distribution)as well as content of trace elements have been defined in sampled materials and several pollution indices(Geoaccumulation index,Contamination factor and Degree of pollution)have been *** obtained show low values of total organic carbon in cryoconites(max.0.23%)but high values(max.7.54%)in top horizon of soils located in floodplain,indicating its active fluvioglacial transfer which may further accelerate the development of *** activity in the studied soils was mostly influenced by additional input of labile organic carbon from cryoconites with water ***-size distribution was similar among the studied cryoconites,indicating dominance of sand fraction(up to 85.28%)while studied soils showed higher variability due to influence of *** the trace elements,cryoconites were mostly polluted by Zn(max.85.70 mg·kg^(-1))which corresponds to high pollution according to pollution indices;Pb(max.24.90 mg·kg^(-1))and Cu(max.17.40 mg·kg^(-1)),up to moderate pollution *** of polluted cryoconite material as well as local anthropogenic activities increased pollution of periglacial soils by Zn(max.89.20 mg·kg^(-1)),Pb(m

关键词： Cryoconites Umbrisols Leptosols Pollution Caucasus mountain range

On Separable Schur Rings over Abelian Groups

在线全文

学校读者我要写书评

暂无评论

Algebra Colloquium 2021年第3期28卷 431-440页

作者： Grigory Ryabov Sobolev Institute of Mathematics NovosibirskRussia Novosibirsk State UniversityNovosibirskRussia

A finite group is said to be weakly separable if every algebraic isomorphism between two 5-rings over this group is induced by a combinatorial *** prove that every abelian weakly separable group only belongs to one of... 详细信息

关键词： isomorphisms Schur rings abelian groups

Isotopic Composition of Atmospheric Precipitation in the Cis-Ural Region

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Earth Science 2022年第3期33卷 831-838页

作者： Alena S.Kazantseva Olga I.Kadebskaya Yuri V.Dublyansky Mining Institute of the Ural Branch of the russian Academy of Sciences PermRussia Institute of Geology University of InnsbruckInnsbruckAustria

Using the Global Network of Isotopes in Precipitation(GNIP)method at three stations in the Cis-Ural region(Iskor,Perm,and Kungur),the monitoring results of the isotope composition of atmospheric precipitation conducted in 2016-2019 are *** lines of meteoric waters were obtained for each station and for the Cis-Ural region as a *** latitudinal zoning of changes in isotope parameters from north to south in the Cis-Ural region is noted,which is related to meteorological *** northern regions are characterized by isotopically light values compared to the southern ***,the correlation relationship between the isotopic compositions of atmospheric precipitation and meteorological parameters at each station is *** analysis data show that about 50%-90%of variations in the isotopic composition of precipitation within the annual cycle are determined by the air *** the same time,the amount of precipitation shows a relationship between the average strength and the isotopic composition of precipitation for a series of observations at Kungur Station;for a series of observations at Iskor and Perm stations,there is no *** in the relationship with meteorological data are explained by different sources of moisture introduction to the station and,accordingly,the formation of the isotopic composition of *** flow of moisture is controlled by the transfer of air masses in different directions,the formation of cyclones and ***,for the northern part of the region during the year is characterized by the predominance of cyclones,whereas for the southern-anticyclones.

关键词： precipitation isotopic composition Cis-Ural region correlation relationship Spear-man’s correlation coefficient

同方期刊数据库

Platinum-group Element Geochemistry of Magnetite from Porphyry-Cu-Mo Deposits and their Host Rocks(Siberia,Russia)

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2012年第1期86卷 106-117页

作者： Anita BERZINA Institute of Geology and Mineralogy Novosibirsk630090Russia

The concentrations of platinum-group elements （PGE） have been analyzed in primary magmatic magnetite samples from the Zhireken, Shakhtama and Aksug porphyry Cu-Mo deposits （Siberia, Russia） by laser ablation-inductively coupled plasma mass spectrometry to determine the range of PGE contents in magnetites and to check whether magnetite from two main rock suites （barren plutonic suite and mineralized porphyry suite） has distinct PGE composition. The results presented here indicate that magnetites are enriched in PGE relative to whole-rocks. Comparison of ore-related porphyry and barren plutonic suites shows that magnetite exhibit relatively similar PGE distribution patterns in both suites. Variations in Rh and Ru contents were controlled by the oxygen fugacity during magma crystallization.

关键词： magnetite platinum-group elements porphyry Zhireken Shakhtama Aksug Siberia,Russia

Paleoclimate Study of Mountain Ecosystems by Multiple Group Biological Analysis

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2011年第1期8卷 24-36页

作者： Marina SKRYPNIKOVA Olga USPENSKAYA Olga KHOKHLOVA Dokuchaev Soil Science Institute of russian Academy of Agricultural Sciences Pyzhevsky Lane7Moscow109017Russia Vegetable Institute of russian Academy of Agricultural Sciences h.500v.VereaRamenskii distMoscow region140153Russia Institute of Physical Chemical and Biological Problems in Soil Science of RASUlitsa Institutskaya2PushchinoMoscow region142290Russia

Methodological problems of climatic reconstruction for different periods of Holocene are discussed on the basis of a multiple group biological analysis on peat-sapropel sediments. The possibility of biological analysis is exemplified by the paleoclimatic reconstruction for Carpathian and Altai Mountain ranges. For the ＂Skolevsky Beskidy＂ national park of Carpaty the paleoclimatic scenarios have been drown up aiming at the more precise definition of climatic conditions for the period of mass mountain slope terracing. The stability of terrace systems of various designs in the current climatic conditions has been assessed. It is shown that during periods of humid climate the terraces, whose designs have been focused on drainage, were built. In periods of dry and warm climate the terrace systems capable of accumulating water were built. Both these types of terrace systems are destroyed in nowadays. Only those terrace systems are stable which were adjusted by their builders to contrast variations of precipitation. For Western Altais the paleoclimatic scenario has been done to forecast the safety of the Bronze Age kurgans （burial earth mounds） with permafrost inside the construction. In the Altay region during the Holocene it has revealed two periods of sharp cooling, the peaks of which occurred in the intervals 4500- 4300 and 2500-2300 years pronounced climatic drying ago, and two periods of 4900-4700 and 130-70 years ago. Depletion of the algae composition in the layer corresponding to the last period of drying climate indicates a very sharp change in the parameters of moisture and turning the lake into a dry swamp. Periods of cold weather may have contributed to the formation of special ritual traditions of the Sakan tribes that require the frozen ground to bury the dead. The later climate fluctuations identified have not affected the safety of permafrost in burial mounds constructed in the V-III cc BC.

关键词： Climatic reconstruction Complex group biological analysis of peat-sapropel sediments Paleopedology Soil evolution Holocene

Using LiF crystals for high-performance neutron imaging with micron-scale resolution

在线全文

学校读者我要写书评

暂无评论

High Power Laser Science and Engineering 2015年第4期3卷 1-9页

作者： A.Faenov M.Matsubayashi T.Pikuz Y.Fukuda M.Kando R.Yasuda H.Iikura T.Nojima T.Sakai M.Shiozawa R.Kodama Y.Kato Institute for Academic Initiatives Suita Osaka University Joint Institute for High Temperatures Russian Academy of Sciences Quantum Beam Science Center Japan Atomic Energy Agency PPC and Graduate School of Engineering Suita Osaka University Nippon SOKEN Inc. The Graduate School for the Creation of New Photonics Industries

This paper describes an overview of our recent discovery – clear demonstration that Li F crystals can be efficiently used as a high-performance neutron imaging detector based on optically stimulated luminescence of color centers generated by neutron irradiation. It is shown that the neutron images we have obtained are almost free from granular noise, have a spatial resolution of～5.4 μm and a linear response with a dynamic range of at least 103. The high contrast and good sensitivity of Li F crystals allow us to distinguish two holes with less than 2% transmittance difference. We propose to use such detectors in areas where high spatial resolution with high image gradation resolution is needed, including diagnostics of different plasma sources such as laser and z-pinch produced plasmas.

关键词： color centers Li F crystals neutron imaging neutrons plasma diagnostics