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Jackson’s theorem in Q_p spaces

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Science China mathematics 2010年第2期53卷 367-372页

作者： CHEN YingWei 1 & REN GuangBin 1, 2, 1 department of mathematics, university of Science and Technology of China, Hefei 230026, China 2 department of mathematics, university of aveiro, P-381.-1.3 aveiro, portugal 1. department of mathematics University of Science and Technology of China Hefei 230026 China2. Department of Mathematics University of Aveiro P-3810-193 Aveiro Portugal

A Jackson type inequality in Q p spaces is established, i.e., for any f (z) = Σ∞ j=0 ajzj ∈ Qp , 0≤p 1, and k-1 ∈ N,where ω(1/k, f, Q p ) is the modulus of continuity in Q p spaces and C(a) is an absolute const... 详细信息

关键词： Q p space BMOA polynomial approximation

Comparative efficiency analysis of different nonlinear modelling strategies to simulate the biaxial response of RC columns

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Earthquake Engineering and Engineering Vibration 2012年第4期11卷 553-566页

作者： Hugo Rodrigues Humberto Varum António Arêde Aníbal Costa university of aveiro Civil Engineering Department Faculty of Natural Sciences Engineering and Technology-Oporto Lusophone University Civil Engineering department Faculty of Engineering University of Porto

The performance of different nonlinear modelling strategies to simulate the response of RC columns subjected to axial load combined with cyclic biaxial horizontal loading is compared. The models studied are classified into two categories according to the nonlinearity distribution assumed in the elements： lumped-plasticity and distributed inelasticity. For this study, results of tests on 24 columns subjected to cyclic uniaxial and biaxial lateral displacements were numerically reproduced. The analyses show that the global envelope response is satisfactorily represented with the three modelling strategies, but significant differences were found in the strength degradation for higher drift demands and energy dissipation.

关键词： RC columns non-linear behaviour biaxial bending fibre modelling

Effect of lead chloride on spermatogenesis and sperm parameters in mice

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Asian Journal of Andrology 2004年第3期6卷 237-241页

作者： António Graca Joao Ramalho-Santos Maria de Lourdes Pereira department of Zoology University of CoimbraCoimbraPortugal Department of BiologyUniversity of Aveiro3810 AveiroPortugalDepartment of ZoologyUniversity of CoimbraCoimbraPortugalDepartment of BiologyUniversity of Aveiro3810 AveiroPortugal

Aim: To evaluate the effect of acute lead chloride exposure on testis and sperm parameters in mice. Methods: PbCl2, 74 mg/kg, was daily administered to sexually mature male mice for 3 days and the effects on the testicular histology and ultrastructure as well as the motility and density of spermatozoa in cauda epididymis were observed. An additional group of mice were treated for 1.3 days and were allowed to recover for 32 days to determine the reversibility of lead-induced changes. Results: The testicular weight, seminiferous tubular diameter and sperm counts were significantly decreased following 3 days of PbCl2 treatment, but were unaffected by shorter-term exposures. The changes caused by lead are mostly reversible. Conclusion: Acute lead chloride exposure injures the fertility parameters of male mice and the effects are partially reversible.

关键词： lead chloride seminiferous tubules epididymis semen analysis

Melt Infiltration Ability and Microstructural Evolution of Fe40Al/TiC Composites System

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Melt Infiltration Ability and Microstructural Evolution of F...

The clustering coefficient,and community structure of bipartite networks

第十届国际制造工程与管理会议

作者： Mingxia Gao, F J Oliveira, Yi Pan, J L Baptista, J M Vieira (1. department of Materials Science and Engineering, Zhejiang university, Hangzhou 310027, China-, 2. department of Ceramics and Glass Engineering/CICECO, university of aveiro, portugal)

Pressureless melt infiltration is an economic route for preparation of high-density ceramic/melt composites. In this study, the Fe40Al iron aluminide intermetallic, a low cost material of excellent oxidation and corrosion resistance, was used as binder for fabricating Fe40Al/TiC composites by pressureless melt infiltration. The wetting ability of liquid Fe40Al in porous TiC preform was studied by in-situ monitoring the melting and infiltration process. The infiltration ability was investigated by observing the distance of liquid Fe40Al intrusion in porous TiC pre-forms at different infiltration temperatures and times by using optical microscope. Porous TiC per-forms with density of 60% - 88%TD (theoretical density), prepared under pre-defined sintering temperature cycles, were used for fabricating Fe40Al/TiC composites in the range of 12% - 40% metal content by volume. Almost full dense Fe40Al/TiC composites were successfully fabricated by this technique. Liquid Fe40Al exhibited excellent infiltration ability, the distance of complete intrusion of liquid Fe40Al in the TiC sintered pre-form with density of 88%TD was over 7 mm after 5 min at the infiltration temperature of 1 450 ℃.Microstructural observation by SEM and TEM also showed that liquid Fe40Al filled the very narrow gaps among TiC particles, the interfaces of TiC particles and Fe40Al plastic ligaments being metallurgical bonded. TEM revealed that high density of dislocations formed in Fe40Al ligaments during solidification, which favor the mechanical properties. Ti decomposed from TiC particles and dissolved into Fe40Al during infiltration. According to the compositional analysis of TEM-EDS, the concentration of Ti in Fe40Al ranges at 1at% - 4at% depending on composite fabricating conditions and the distance from the measuring point to the closest TiC particles. XRD analysis indicated that the composites were composed of two phases, the original TiC and Fe0.4Al0.6 intermetallic. No new phase formed during in

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来源： cnki会议评论

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The clustering coefficient,and community structure of bipart...

EFFECT OF PHOTOOXIDATION ON PHOTOLUMINESCENCE OF N, N'-DIPHENYL-N, N'-DI(M-TOLYL)-BENZIDINE AND RUBRENE CODOPED PMMA THIN FILMS

第四届全国网络科学学术论坛暨研究生暑期学校

作者： Peng Zhang~(1,2) Jinliang Wang~1 XiaoJia Li~1 Menghui Li~1 Zengru Di~1 Ying Fan~(1*) 1.department of Systems Science,School of Management,Beijing Normal university,Beijing 100875,P.R.China. 2.departmento de Fisica da Univesidade de aveiro,381.-1.3 aveiro,portugal

Many real-wold networks display a natural bipertite ***- vestigating them based on the original structure is helpful to get deep understanding about the *** this paper,a modificstion of the clustering coefficient in bipartite networks on the consideration of cy-cles with size four is *** comparing the two definitions in a given graph,the results show *** modification one is better to character the *** order to detect community structure in bipar- tire networks,two different edge clustering coeffcients LC and of LC of tite networks are defined,which basde on squares and triples respec- *** the algorithm of cutting the edge with the least clustering coeffcient,community structures in artificial and real world networks are *** results are different from the community structures given based on the one mode projection.

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来源： cnki会议评论

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Acta Metallurgica Sinica(English Letters) 2001年第6期14卷 441-447页

作者： YB. Hou, L.J. Meng and M.P. dos Santos ( department of Physics, Minho university, Braga 4719, portugal) ( Departamento de Fisica, Instituto Superior de Engenharia do Porto, Rua de Sao Tome, 4200 Porto, portugal) Dept. of Phys. Minho Univ. Braga 4719 Portugal

In this paper, the PMMA films doped with N,N'-diphenyl-N,N'-di(m-tolyl)-benzidine and rubrene were fabricated by spin coating, and the effect of photooxidation on the photoluminescence of the doped PMMA thin films was investigated. The results showed that under the irradiation of 350nm UV light, N,N'-diphenyl-N,N'-di(m-tolyl)-benzidine can sensitized rubrene and results in the enhancement in the photooxidation of rubrene. The effect of photooxidation on the photoluminescence from rubrene was more obvious. Both lifetime measurement and in situ measurement of photoluminescence showed that rubrene molecules exist in two chemical surroundings.

关键词： photoluminescence photooxidation

X（3872） and Bound State Problem of D0*0（0 D*0）

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原子核物理评论 2009年第S1期 16-21页

作者： LIU Yan-rui1,LIU Xiang2,3,DENG Wei-zhen2 (1 Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China 2 department of Physics,Peking university,Beijing 100871,China 3 Centro de Física Terica,Departamento de Física,Universidade de Coimbra,P-3004-516,Coimbra,portugal)

We have performed a dynamical calculation of the bound state problem of D0D*0 by considering the pion and sigma meson exchange potential. Our preliminary analysis disfavors the molecular interpretation of X(3872) if we use the experimental D*Dπ coupling constant g=0.59 and a reasonable cutoff around 1 GeV,which is the typical hadronic scale. In contrast,there probably exists a loosely bound S-wave BB* molecular state. Such a molecular state would be rather stable since its dominant decay mode is the radiative decay through B*→Bγ.

关键词： X(3872) bound state molecule

Numerical Study of Spray Dispersion in a Premixing Chamber for Low-NOx Engines

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Journal of Thermal Science 2000年第3期9卷 282-288页

作者： Jorge Barata Andre Silva (Universidade da Beira Interior, Aerospace Sciences department, Rua Marques d’Avila e Bolama, 6200 Covilha, portugal ) Aerospace Sciences department Universidade da Beira Interior Covilhã Portugal

The present work describes a numerical study of a confined two-phase flow under high-pressure conditions, typical of gas turbine combustors. An Eulerian frame was used for the gas phase together with a Lagrangian approach to describe the dispersed phase. The computational method was extended to high-pressure environments, which are more representative of the practical gas turbine operating conditions. The results are compared with experimental data, and revealed the ability of the model to increase the knowledge of the turbulent dispersion phenomena for this type of practical conditions (high pressure and confined flow).

关键词： two-phase flows sprays high pressure.

Phylogeny of Culex theileri virus flavivirus in Spain, Myanmar, portugal and Turkey

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Asian Pacific Journal of Tropical Medicine 2019年第5期12卷 216-223页

作者： Eleonora Cella Domenico Benvenuto Daniele Donati Francesco Garilli Silvia Angeletti Stefano Pascarella Massimo Ciccozzi Unit of Medical Statistics and Molecular Epidemiology,university Campus Bio-Medico of Rome School of Nursing,Faculty of Medicine,department of Biomedicine and Prevention,Tor Vergata university Faculty of Medicine,university Campus Bio-Medico of Rome Unit of Clinical Laboratory Science,university Campus Bio-Medico of Rome department of Biochemical Sciences'A.Rossi Fanelli',university of Rome'La Sapienza' Unit of Medical Statistics and Molecular Epidemiology University Campus Bio-Medico of Rome School of Nursing Faculty of Medicine Department of Biomedicine and Prevention Tor Vergata University Faculty of Medicine University Campus Bio-Medico of Rome Unit of Clinical Laboratory Science University Campus Bio-Medico of Rome department of Biochemical Sciences"A.Rossi Fanelli" University of Rome "La Sapienza"

Objective: To study the genetic diversity of Culex theileri flavivirus and the spread of this virus among Spain, portugal and ***: A database consisting of 55 sequences of the NS5/3'UTR region of Culex theileri flavivirus group downloaded from GenBank were aligned and manual edited with *** est v.3.7 was used to select the simplest evolutionary model that adequately fitted the sequence *** likelihood analysis was performed using *** phylogenetic signal of the dataset was investigated by the likelihood mapping ***: The phylogenetic tree showed three *** sequences clusterd together with Turkish sequences, Spain and portugal strains grouped together and two Turkish sequences grouped *** pressure analysis showed a moderate percentage of sites(22.5%) under pervasive negative selection and only 1% under pervasive positive *** sites subject to selective pressure in CTFV RdRp NS5 fragments have been located onto the predicted three-dimensional ***: Phylogenetic and evolutionary analysis can be an important tool for understanding the evolutionary impact of the probable contemporary existence between nonpathogenic and pathogenic flaviviruses among these vectors.

关键词： Culex virus Flaviviridae Phylogenetic analysis Evolution