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Biochronology,paleobiogeography and faunal turnover in western mediterranean Cenozoic mammals

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Integrative Zoology 2009年第4期4卷 367-386页

作者： maria r.PALOmBO Department of Earth Sciences University of Rome“La Sapienza”RomeItaly

Cenozoic terrestrial mammals from Sardinia contribute substantial information for reconstructing the complex his-tory of the western *** occurrence of endemic perissodactyls in Eocene marine and marsh deposits suggests the existence of ecological or physical barriers between the Corso-Sardinian massif and the Iberian-Occitanic *** the end of the Oligocene,isolation of Sardinia was almost complete,although a migration from Europe occurred at the beginning of the Early miocene,as indicated by the unbalanced endemic fauna from *** the Late miocene,the Tusco-Sardinian palaeobioprovince came into existence as an isolated region inhab-ited by the quite diversified,but notably endemic,Oreopithecus *** was definitely isolated from Tuscany by the messinian,but temporary connections with the European mainland possibly allowed the colonization of forerunners of some Sardinian Pliocene *** the Plio-Pleistocene,Sardinia maintained permanent ***,sea level drop,resulting in a relatively short distance between Sardinia and the European mainland,allowed different migratory *** the Late Pliocene to the Late Pleistocene–Holocene,two main mammalian faunal complexes(fC)can be recognized:the Nesogoral fC(Late Pliocene-Early Pleistocene)and the microtus(Tyrrhenicola)fC(late Early Pleistocene–Early Holocene).At the transition from Nesogoral to microtus(Tyrrhenicola)fC,approximately 47%of the genera and 76%of the species disappeared,while approximately 58%of the genera and 71%of the species appeared.A noticeable turnover followed the arrival of Neolithic man and his accompanying ***,Praemegaceros was still present at about 7000 years BP,while microtus(Tyrrhenicola)and Prolagus are respectively recorded in the Bronze and Iron Ages.

关键词： biochronology Cenozoic faunal turnovers mammals Sardinia

model Predictions of Charged-Particle Azimuthal Distributions and forward-Backward Correlations in pp Interactions at s1/2= 900 GeV

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Communications in Theoretical Physics 2019年第10期71卷 1172-1178页

作者： r.Khan m.Ajaz Y.Ali H.Younis G.Khan Z.Wazir A.Zaman A.Khan Department of Physics Abdul Wali Khan UniversityMardan23200Pakistan Department of Physics COMSATS UniversityIslamabad44000Pakistan Department of Physics International Islamic UniversityIslamabad44000Pakistan

We report inelastic interactions of protons at the center of mass energy s1/2 = 900 Ge V, by using different event generators to study the forward-backward(fB) correlation in summed transverse momentum and multiplicity of produced charged particles. The transverse momentum, p T ≥ 100 me V, and pseudorapidity, | η |mployed for both the correlations. The simulation results are compared with the ATLAS experimental data, obtained with the same values of | η | and p T at s1/2 = 900 Ge V. We also measure the jet and jet-like structure as a function of azimuthal distributions in the events relative to the highest transverse momentum particle. Three overlapping regions of pseudorapidity, | η |re used with transverse momentum, p T > 500 me V. for fB correlations, EPOS, and Sybill2.3 c results are in a good agreement with the data as compared to the other ***, for the azimuthal distribution, EPOS-LHC, DPmJETIII, and Sibyll2.3 c show good agreement with the data for full η region. In general, EPOS provides a better description of the data for both the quantities studied in this paper.

关键词： forward-backward correlation CrmC models LHC ATLAS

Carbon and nitrogen mineralization in soil of leguminous trees in a degraded pasture in northern rio de Janeiro, Brazil

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Journal of forestry research 2016年第1期27卷 91-99页

作者： Danielle A. D. Nunes Emanuela f. Gama-rodrigues Patricia A. B. Barreto[ Antonio C. Gama-rodrigue Paulo H. m. monroe Chemistry School Rio de Janeiro Federal UniversityRio de Janeiro RJ 21941-909 Brazil Soil Laboratory North Fluminense State UniversityCampos dos Goytacazes RJ 28013-602 Brazil Department of Soil and Agricultural Engineering State University of Southwest Bahia Vitoda da ConquistaBA 45031-300 Brazil

Use of legume trees can improve soil quality in degraded pastures. The aim of this study was to charac- terize C and N mineralization kinetics and estimate the potentially mineralizable C and N in soil under mimosa caesalpiniifolia Benth. and Acacia auriculiformis A. Cunn. ex Benth. secondary forest and pasture in red-yellow latosols in southeast Brazil. We conducted a laboratory aerobic incubation experiment using a completely ran- domized design of four replicates and four types of plant cover using a modified version of the Stanford and Smith technique （1972） to study C and N mineralization potential. Potentially mineralizable N （No） ranged from 135 to 170 mg kg-1. The predominant form of mineral N for all types of plant cover was N-NO3-. m. caesalpiniifolia was the only species that had a positive influence on N min- eralization. Neither of the legumes influenced C mineral- ization in pasture or secondary forest. The model of N mineralization corresponded to a sigmoidal curve while C mineralization corresponded to an exponential curve, revealing that the N and C mineralization processes were distinct. N mineralized by m. caesalpiniifolia （216 kg ofN ha-1） was adequate to meet the N requirement for a livestock-forest system.

关键词： Carbon dioxide forest soil mineralized N Organic matter Soil microorganisms

Halogen versus halide electronic structure

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Science China Chemistry 2010年第1期53卷 210-215页

作者： Willem-Jan van Zeist f.matthias Bickelhaupt Department of Theoretical Chemistry and Amsterdam Center for multiscale modeling Scheikundig Laboratorium der Vrije UniversiteitDe Boelelaan 1083NL-1081 HV AmsterdamThe Netherlands

Halide anions X-are known to show a decreasing proton affinity(PA),as X descends in the periodic table along series f,Cl,Br and *** it is also well-known that,along this series,the halogen atom X becomes less electronegative(or more electropositive).This corresponds to an increasing energy of the valence np atomic orbital(AO) which,somewhat contradictorily,suggests that the electron donor capability and thus the PA of the halides should increase along the series f,Cl,Br,*** reconcile these contradictory observations,we have carried out a detailed theoretical analysis of the electronic structure and bonding capability of the halide anions X-as well as the halogen radicals X-,using the molecular orbital(mO) models contained in Kohn-Sham density functional theory(DfT,at SAOP/TZ2P as well as OLYP/TZ2P levels) and ab initio theory(at the Hf/TZ2P level).We also resolve an apparent intrinsic contradiction in Hartree-fock theory between orbital-energy and PA *** results of our analyses are of direct relevance for understanding elementary organic reactions such as nucleophilic substitution(SN2) and base-induced elimination(E2) reactions.

关键词： bond theory halogen hydrogen-atom affinity orbital energy proton affinity reactivity

Critical Point Theorems and Applications to Differential Equations

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Acta mathematica Sinica,English Series 2005年第1期21卷 129-142页

作者： A.r.EL AmrOUSS University mohamed I Faculty of SciencesDepartment of MathematicsOujdaMorocco

This paper contains a generalization of the well–known Palais–Smale andCerami compactness conditions. The compactness condition introduced is used to prove some generalexistence theorems for critical points. Some ap... 详细信息

关键词： Critical point theory Semilinear elliptic boundary values problems Hamiltonian systems resonance

定频与变频冰箱贮藏对鲜切西瓜品质及微生物数量的影响

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食品工业科技 2014年第14期35卷 351-355,358页

作者：赵亚丽 Esequias pereira 洪凯高岩杨平刘野北京恩布拉科雪花压缩机有限公司北京101312 北京工商大学食品风味化学北京市重点实验室/食品添加剂与配料北京高校工程研究中心北京100048

为探究定频和变频冰箱贮藏对果蔬品质、风味和微生物的影响,选取鲜切西瓜为试材,对其在144h贮藏期内上述指标的变化趋势做出分析。结果表明,虽然经定频和变频冰箱贮藏后,鲜切西瓜多酚氧化酶和抗坏血酸含量均呈逐渐降低的趋势,还原糖含... 详细信息

为探究定频和变频冰箱贮藏对果蔬品质、风味和微生物的影响,选取鲜切西瓜为试材,对其在144h贮藏期内上述指标的变化趋势做出分析。结果表明,虽然经定频和变频冰箱贮藏后,鲜切西瓜多酚氧化酶和抗坏血酸含量均呈逐渐降低的趋势,还原糖含量呈先降低后升高的趋势,但变频冰箱贮藏鲜切西瓜多酚氧化酶和抗坏血酸含量高于定频冰箱,并且己醛、6-甲基-5-庚烯-2-酮、壬醛、反-6-壬烯醛、顺-2-壬烯醛、反,顺-2,6-壬二烯醛几种关键香气成分含量更高,大肠杆菌数量和菌落总数显著少于定频冰箱。总体看来,在鲜切西瓜贮藏方面变频冰箱比定频冰箱具有更大的优势。

关键词：定频变频鲜切西瓜品质

BEHAVIOr Of SHOrT fATIGUE CrACKS AT BLUNT NOTCHES IN A mEDIUm CArBON STEEL

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Acta metallurgica Sinica(English Letters) 1997年第5期10卷 430-436页

作者： Wu, Z.X. Sun, X.f. Southwest Jiaotong Univ Chengdu China

The behavior of part-through and through short cracks in single edge blunt notched specimens of a medium carbon steel was investigated by a replication method. It is found that the fatigue failure of these notched specimens is caused mainly by the growth of short surface cracks originating from the surface of notch root. more than 70% of the fatigue life is spent in the regimes in which short surface cracks initiate and propagate as part-through cracks before joining up to form a single through-thickness crack. The effect of original crack profile which is formed through the coalescence of multiple part-through cracks is the main reason causing the 'anomalous' propagation behavior of the through-thickness crack in its early stage.

关键词： Carbon steel Crack initiation Crack propagation fatigue of materials fracture mechanics Surfaces

NOISE CONTrOL IN THE WESTErN WOrLD OVEr THE PAST 2000 YEArS

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Chinese Journal of Acoustics 1988年第2期7卷 176-182页

作者： T.f.W.Embleton Division of Physics National research Council Canada

The histroical courcse concerning some noise events and its control over the past 2000 years in North America and parts of Western Europe is described.

关键词： NOISE CONTrOL IN THE WESTErN WOrLD OVEr THE PAST 2000 YEArS

Comparative study of Sm^(3+) ions doped phosphate based oxide and oxy-fluoride glasses for solid state lighting applications

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Journal of rare Earths 2019年第4期37卷 374-382页

作者： m.Shoaib G.rooh r.rajaramakrishna N.Chanthima N.Kiwsakunkran H.J.Kim J.Kaewkhao S.Tuscharoen Department of Physics Abdul Wali Khan University Center of Excellence in Class Technology and materials Science (CEGm) Nakhon Pathom Rajabhat University Physics Program Faculty of Science and TechnologyNakhon Pathom Rajabhat University Department of Physics Kyungpook National University

The physical and luminescent properties of Sm^(3+)-doped oxide and oxy-fluoride phosphate glasses were investigated. The glass samples with chemical composition of 69 P_2 O_5-10 BaO-10 ZnO-10 Gd_2 O_3-1 Sm_2 O_3 and 69 P_2 O_5-10 BaO-10 ZnO-10 Gdf_3-1 Sm_2 O_3 were prepared by conventional melt quenching technique. The prepared glass samples were characterized with density, molar volume, refractive index,fTIr, UV-Vis-NIr, photo luminesce nce, radio luminescence, decay time profile and CIE diagram. The density and refractive index of the oxide glass have higher values as compared to the oxy-fluoride *** fTIr spectra show the reduction of O-H group in oxy-fluoride glass. The characteristic peaks of Sm^(3+)are observed at 360,372,402,438,419,473,944,1077,1227,1373,1474,1529 and 1585 nm in UV-VIS-NIr spectra. These peaks are related respectively to the transitions from ground state ~6 H_(5/2) to ~4 D_(3/2), ~6 P_(7/2),6 P3/2, ~4 I_(11/2), ~6 f_(11/2), ~6 f_(9/2), ~6 f_(7/2),~6 f_(5/2),~6 f_(3/2), ~6 H_(15/2) and ~6 f_(1/2) excited states. from photoluminescence and radio-luminesce nce it is observed that the oxy-fluoride glass samples show better emission intensity than the oxide glass. The Judd-Ofelt theory(J-0 theory) was used to find J-O intensity Ω_λ(λ = 2,4 and 6)parameters and radiative properties such as transition probability, stimulated emission cross section and branching ratios for titled glasses. The trend observed in the J-O parameters is Ω_4 >Ω_2 >Ω_6. The transition probability,emission cross section and branching ratio have the highest values for the ~4 G_(5/2)→~6 H_(7/2)transition. The CIE coordinates of the prepared glass samples are positioned in the orange region and the CCT value is 3776.105 for oxide and oxyfluoride glass. The oxy-fluoride glass has shorter decay time as compared to the oxide glass and it is recorded to be 1.62 and 1.32 ms for oxide and oxy-fluoride respectively. According to the results obtained in this work, it is obvious t

关键词： Oxy-fluoride glass Photoluminescence Judd-Ofelt theory CIE coordinates rare earths