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Statistical analysis of geomagnetic field variations during the partial solar eclipse on 2011 January 4 in Turkey

Research in Astronomy and Astrophysics 2015年第5期15卷 742-752页

作者： Abdullah Ates Yunus Levent Ekinci Aydin Buyuksarac attila Aydemir Alper Demirci Ankara University Faculty of Engineering Department of Geophysical Engineering BesevlerTR-06100 Ankara Turkey Bitlis Eren University Faculty of Arts and Sciences Department of Archaeology TR-13000Bitlis Turkey Bitlis Eren University Faculty of Engineering and Architecture Department of Civil Engineering TR-13000 Bitlis Turkey Turkish Petroleum Corp. Sogutozu Mah. 2180. Cad. No: 10 Sogutozu TR-06100 AnkaraTurkey Bitlis Eren University Faculty of Engineering and Architecture Department of Geophysical Engineering TR-13000 Bitlis Turkey

Some geophysical parameters, such as those related to gravitation and the geomagnetic field, could change during solar eclipses. In order to observe geomagnetic fluctuations, geomagnetic measurements were carded out in a limited time frame during the partial solar eclipse that occurred on 2011 January 4 and was observed in Canakkale and Ankara, Turkey. Additionally, records of the geomagnetic field spanning 24 hours, obtained from another observatory （in Iznik, Turkey）, were also analyzed to check for any peculiar variations. In the data processing stage, a polynomial fit, following the application of a running average routine, was applied to the geomagnetic field data sets. Geomagnetic field data sets indicated there was a characteristic decrease at the beginning of the solar eclipse and this decrease can be well-correlated with previous geomagnetic field measurements that were taken during the total solar eclipse that was observed in Turkey on 2006 March 29. The behavior of the geomagnetic field is also consistent with previous observations in the literature. As a result of these analyses, it can be suggested that eclipses can cause a shielding effect on the geomagnetic field of the Earth.

关键词： Sun magnetic field -- eclipses -- methods data analysis -- methods statistics

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Crystal field and magnetism with Wannier functions: rare-earth doped aluminum garnets

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Journal of Rare Earths 2015年第12期33卷 1316-1323页

作者： Eva Mihóková Pavel Novák Valentin V.Laguta Institute of Physics Czech Academy of Sciences

Using the recently developed method we calculated the crystal field parameters m yttrium anct lutetium aluminum garnets doped with seven trivalent Krarners rare-earth ions. We then inserted calculated parameters into the atomic-like Hamiltonian taking into account the electron-electron, spin-orbit and Zeeman interactions and determined the multiplet splitting by the crystal field as well as magnetic tensors. We compared calculated results with available experimental data. Very good agreement with the spectroscopic data and qualitative agreement with experimental tensors was found.

关键词： crystal field ab initio calculations gamets rare earths

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Forest Disturbance Enhanced the Activity of Epedaphic Collembola in Windthrown Stands of the High Tatra Mountains

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Journal of Mountain Science 2014年第2期11卷 449-463页

作者： Veronika URBANOVIOVá Dana MIKLISOVá Lubomír ková Institute of Biology and Ecology Faculty of Science P.J. Safárik UniversityMoyzesova 11 Kosice 04001 Slovakia Institute of Parasitology Slovak Academy of SciencesHlinkova 3 Kosice 04001 Slovakia

The study aimed to assess the response of ep- and hemiedaphic Collembola communities(activity, richness, community structure) to a disturbance, the subsequent management regime and to the season(summer, winter) in a High Tatra Mountains spruce forest destroyed by a *** and clear-cut resulted in an initial increase in the activity of Collembola inhabiting open areas,opportunistic or generalist species, while forest specialists diminished in numbers or *** results indicated that treatment with nonextracted fallen trees(NEX) provided a better chance for forest species to survive compared with their survival in open habitats of extracted(EXT) and wildfire(FIR) treatments. Great species' potential of NEX treatment was indicated by Chao2 estimator and activity/species rarefaction curves. Communities of NEX treatment were more similar to the reference(REF) treatment, documented by ordination and cluster analyses. Thus, leaving fallen timber after a windthrow to natural process of succession is suitable for survival of forest species and maintenance of diversity in forests restoration than timber *** structure in wildfire(FIR) stands was the most dissimilar to the other treatments. Most of the species trapped in this treatment belonged to hemiedaphic life forms, while the activity of larger epedaphic species diminished. In contrast, the highest number of trapped Collembola in EXT treatment was connected with the larger-bodied epigeic species with fast dispersal ability. The trapping period affected both the number of individuals and species richness;Collembola activity and species diversity in the individual treatments were lower in winter compared with the summer period. Several species increased activity during the winter period, namely Folsomia penicula, Friesea mirabilis, F. truncata, Hypogastrura socialis and Protaphorura aurantiaca.

关键词： Wildfire Windstorm Clear-cutting Collembola Spruce forest

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Effects of Carbon Content and Solidification Rate on the Thermal Conductivity of Grey Cast Iron

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Tsinghua Science and Technology 2008年第2期13卷 170-176页

作者： Daniel Holmgren attila Diószegi Ingvar L. Svensson Department of Mechanical Engineering and Component Technology Jnkping University

The thermal conductivity/diffusivity of pearlitic grey irons with various carbon contents was investigated by the laser flash method. The materials were cast in controlled thermal environments producing three dissimilar cooling rates. The cooling rates together with the carbon content largely influence the thermal conductivity of grey iron. Linear relationships exist between the thermal conductivity and the carbon content, the carbon equivalent, and the fraction of the former primary solidified austenite transformed into pearlite. The results show that the optimal thermal transport properties are obtained at medium cooling rates. Equations are given for the thermal conductivity of pearlite, solidified as pre-eutectic austenite, and the eutectic of grey iron. The thermal conductivity of pearlitic grey iron is modelled at both room temperature and elevated temperatures with good accuracy.

关键词： grey iron thermal conductivity thermal diffusivity carbon content carbon equivalent color etching graphite morphology eutectic cell size

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Arylation of Allylic Alcohols with Aryl Iodides Catalyzed by a Silica-Bound Bidentate Sulfur Palladium (0) Complex

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Chinese Chemical Letters 1998年第5期9卷 427-430页

作者： Cai, MZ Song, cs Huang, X Hangzhou Univ Dept Chem Hangzhou 310028 Peoples R China Jiangxi Normal Univ Dept Chem Nanchang 330027 Peoples R China

Allylic alcohols react with aryl iodides in the presence of tri-n-butylamine and a catalytic amount of a silica-bound bidentate sulfur palladium (0) complex to form 3-arylaldehydes or ketones in good yields.

关键词： supported palladium catalyst arylation allylic alcohol sulfur palladium complex

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A New Lignan Glucoside from Lancea tibetica

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Chinese Chemical Letters 1999年第1期10卷 37-38页

作者： Su, BN Yuan, cs Jia, ZJ Lanzhou Univ Natl Lab Appl Organ Chem Dept Chem Lanzhou 730000 Peoples R China

A new 7-9'-monoepoxy tetrahydrofuran type lignan glucoside with the cis-relationship of H-7 and H-8, named tibeticoside A 1, was isolated from the medicinal whole plants of Lancea tibetica. Its structure was elucidate... 详细信息

关键词： Lancea tibetica scrophulariaceae tibeticoside A

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Microstructure and Deformation Behavior of Ti-10V-2Fe-3Al Alloy during Hot Forming Process

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Journal of Wuhan University of Technology(Materials Science) 2015年第6期30卷 1332-1337页

作者：管仁国 ZHAO Zhanyong Choi KS Lee cs Key Laboratory of Electromagnetic Processing of Materials of Ministry of Education Northeastern University College of Materials Science and Engineering Northeastern University Materials and Metallurgical School Pohang University of Science and Technology

The microstructure evolution and formability of Ti-10V-2Fe-3Al alloy related to the initial microstructures and processing variables were investigated during hot forming process. The experimental results show that the α-phase growth is controlled by solute diffusion during the heat treatment processes. Four different microstructures were established by combinations of several heat treatments, and Ti-10V-2Fe-3Al alloy shows excellent formability both above and below the β transus temperature. The alloy possesses low deformation resistance and active restoration mechanism during the deformation. A constitutive equation describing the hot deformation behavior of Ti-10V-2Fe-3Al alloy was obtained. Higher fl ow stress was observed for the acicular morphology of α phase in microstructures with large aspect ratios as compared with that of small aspect ratios. Due to the dynamic recovery in soft β phase, and the dynamic recrystallization and breakage of acicular α-phase, fl ow softening occurred signifi cantly during deformation. Dynamic recrystallization also occurred especially in the severely deformed regions of forged parts.

关键词： Ti-10V-2Fe-3Al alloy microstructure evolution hot forging constitutive equation recovery dynamic recrystallization

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Deductive way of reasoning about the internet AS level topology

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Chinese Physics B 2015年第11期24卷 633-642页

作者： Dávid Szabó attila Korsi József Bíró András Gulyás High Speed Networks Laboratory Budapest University of Technology and Economics MTA-BME Information Systems Research Group Budapest University of Technology and Economics MTA-BME Future Internet Research Group Budapest University of Technology and Economics

Our current understanding about the AS level topology of the Internet is based on measurements and inductive-type models which set up rules describing the behavior （node and edge dynamics） of the individual ASes and generalize the consequences of these individual actions for the complete AS ecosystem using induction. In this paper we suggest a third, deductive approach in which we have premises for the whole AS system and the consequences of these premises are determined through deductive reasoning. We show that such a deductive approach can give complementary insights into the topological properties of the AS graph. While inductive models can mostly reflect high level statistics （e.g., degree distribution, clustering, diameter）, deductive reasoning can identify omnipresent subgraphs and peering likelihood. We also propose a model, called YEAS, incorporating our deductive analytical findings that produces topologies contain both traditional and novel metrics for the AS level Internet.

关键词： internet topology complex network analysis model

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Limsup Results and LIL for Partial Sum Processes of a Gaussian Random Field

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Acta Mathematica Sinica,English Series 2008年第9期24卷 1497-1506页

作者： Yong-Kab CHOI Mikls csRG Department of Mathematics and RINS Gyeongsang National University Jinju 660-701 Republic of Korea School of Mathematics and Statistics Carleton University 1125 Colonel By DriveOttawa K1S 5B6 Canada

Let {ξ j ; j ∈ ℤ+ d be a centered stationary Gaussian random field, where ℤ+ d is the d-dimensional lattice of all points in d-dimensional Euclidean space ℝd, having nonnegative integer coordinates. For each j = (j 1 , ..., jd) in ℤ+ d , we denote |j| = j 1 ... j d and for m, n ∈ ℤ+ d , define S(m, n] = Σ mζ j , σ2(|n−m|) = ES 2 (m, n], S n = S(0, n] and S 0 = 0. Assume that σ(|n|) can be extended to a continuous function σ(t) of t > 0, which is nondecreasing and regularly varying with exponent α at b ≥ 0 for some 0 < α < 1. Under some additional conditions, we study limsup results for increments of partial sum processes and prove as well the law of the iterated logarithm for such partial sum processes.

关键词： stationary Gaussian random field regularly varying function large deviation probability law of the iterated logarithm

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Associative learning in plants:light quality history may matter

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BIOCELL 2022年第3期46卷 645-649页

作者： FATIMA CVRČkovÁ HANA KONRÁDOVÁ Department of Experimental Plant Biology Faculty of ScienceCharles UniversityPragueCZ 12843Czech Republic

The possibility of associative learning in plants is a topic of ongoing *** one published study,growing pea plants were reported to associate two stimuli(airflow and light)and thereafter use one(airflow)as an indicator for the other(light),similar to dogs in Pavlov’s famous ***,this observation could not be independently *** we examine a possible reason for the failure of a published reproduction attempt,which used substantially different light quality during plant cultivation prior to experimental treatments than in the original *** could have resulted in dramatically different growth *** the relevance of the original report of plant associative learning remains questionable,greater attention should be paid to good documenting and standardizing the light conditions,in particular spectral quality,not only in studies of plant learning and memory,but also in other areas of experimental plant biology.

关键词： Classical conditioning Light quality Phototropism Replicability Reproducibility

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