检索结果-南通市图书馆

Luminosity function of optically-selected type II QSOs

在线全文

学校读者我要写书评

暂无评论

Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 191-195页

作者： BIAN WeiHao & ZHANG ShiYan Department of physics,Nanjing normal university,Nanjing 210097,china Department of physics Nanjing Normal University Nanjing China

For a sample of 411 type II QSOs with redshifts less then 0.3,we use the Balmer decrements to do the reddening correction of the [O III] luminosities and then derive the intrinsic [O III] luminosity *** find that the host reddening correction of the [O III] 5007 luminosity for type II QSOs cannot be *** median Balmer decrement of Hα/Hβ=4.0 corresponds to an extinction of 0.94 mag for the [O III] 5007 line,which is consistent with the result derived from the median Hβ/Hγ.Comparing the intrinsic luminosity function of type II QSOs with that of type I QSOs,we find that the upper limit of the type II QSO’s fraction in the total QSOs is 80% for type II QSOs with z 4.

关键词： type II QSOs luminosity function emission lines Balmer decrements

The littlest Higgs model with T-parity and some lepton flavor violation decay processes

在线全文

学校读者我要写书评

暂无评论

Science china(physics,Mechanics & Astronomy) 2010年第11期53卷 1968-1974页

作者： YUE ChongXing,MA Wei,ZHANG TingTing,LIU Wei & LIU JinYan Department of physics,Liaoning normal university,Dalian 116029,china Department of physics Liaoning Normal University Dalian China

The new particles predicted by the littlest Higgs model with T-parity (called LHT model) can induce the lepton flavor violation (LFV) couplings at the one-loop level,which can add contributions to some LFV *** into account the constraints of the experimental data on the relevant free parameters,we calculate the branching ratios of the LFV decay processes Z → l ˉl and τ-→μ-P 1 P 2 with P 1 P 2 = π + π-,K + K-,and K0 ˉK 0 in the context of this new physics *** find that the LHT model can indeed make significant contributions to some of these LFV decay *** Z factory option for the future high energy e + e-collider experiments will give severe constraints on the LHT model.

关键词： littlest Higgs model lepton flavor violation branching ratios

Duality properties between spectra and tilings

在线全文

学校读者我要写书评

暂无评论

Science china Mathematics 2010年第5期53卷 270-280页

作者： LI JianLin college of Mathematics and Information Science,Shaanxi normal university,Xi’an 710062,china college of Mathematics and Information Science Shaanxi Normal University Xi’an China

Spectra and tilings play an important role in analysis and geometry *** relations between spectra and tilings have bafied the mathematicians for a long *** conjectures,such as the Fuglede conjecture,are placed on the establishment of relations between spectra and tilings,although there are no desired *** the present paper we derive some characteristic properties of spectra and tilings which highlight certain duality properties between them.

关键词： spectral pair periodic set packing and covering tiling pair

Synthesis and Electrochemical Properties of Mg-doped LiNi_(0.6)Co_(0.2)Mn_(0.2)O_2 Cathode Materials for Li-ion Battery

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan university of technology(Materials Science) 2011年第2期26卷 212-216页

作者：傅春燕 Shaoyang Medical college Level Speciaity School Department of Pharmacy

The layered LiNi0.6Co0.2-xMn0.2MgxO2 （x=0.00,0.03,0.05,0.07） cathode materials were prepared by a co-precipitation *** properties of the Mg-doped LiNi0.6Co0.2Mn0.2O2 were investigated by X-ray diffraction （XRD）,scanning electron microscopy （SEM）,and electrochemical *** studies showed that the Mg-doped LiNi0.6Co0.2Mn0.2O2 had the same layered structure as the undoped *** SEM images exhibited that the particle size of Mg-doped LiNi0.6Co0.2Mn0.2O2 was finer than that of the undoped LiNi0.6Co0.2 Mn0.2O2 and that the smallest particle size is only about 1μ*** Mg-doped LiNi0.6Co0.2Mn0.2O2 samples were investigated on the Li extraction/insertion performances through charge/discharge,cyclic voltammogram （CV）,and electrochemical impedance spectra（EIS）.The optimal doping content of Mg was that x= 0.03 in the LiNi0.6Co0.2-xMn0.2MgxO2 samples to achieve high discharge capacity and good cyclic *** electrode reaction reversibility and electronic conductivity was enhanced,and the charge transfer resistance was decreased through *** improved electrochemical performances of the Mg-doped LiNi0.6Co0.2Mn0.2O2 cathode materials are attributed to the addition of Mg 2＋ ion by stabilizing the layer structure.

关键词： lithium ion batteries LiNi0.6Co0.2Mn0.2O2 Mg-doping cyclic voltammogram (CV)

The toxicity of Cu^(2+) to Microcystis aeruginosa using dielectric spectroscopy

在线全文

学校读者我要写书评

暂无评论

Science china Chemistry 2010年第3期53卷 631-636页

作者： YU YanLi1,BAI Wei1,ZHAO KongShuang1& ZHOU YunLong2 1college of Chemistry,Beijing normal university,Beijing 100875,china 2college of Life Science,Beijing normal university,Beijing 100875,china college of Chemistry Beijing Normal University Beijing China college of Life Science Beijing Normal University Beijing China

Dielectric spectroscopy(DS) was utilized to investigate the toxicity of the Cu2+ solution to Microcystis *** was found that 0.04 mM Cu2+ had no effect on dielectric increment,whereas the Cu2+ concentrations above 0.1 mM decreased the value of Δε/Δε *** toxic effect of Cu2+ on *** cells was time-dependent and *** was a threshold concentration between 0.04 mM and 0.1 mM,which affected the cell membrane,suggesting that Cu2+ at the concentrations higher than 0.1 mM caused serious plasmalemma damage to *** *** addition of 1 mM Ca2+ or Mg2+ did not protect *** cells from 1 mM Cu2+ *** study demonstrates that DS monitors cell biomass facilitating observation of the toxic effects of metal ions.

关键词： Microcystis aeruginosa dielectric spectroscopy dielectric increment cupric ion toxicity

Morphology and the M_(BH)-σ_* relation for NLS1s

在线全文

学校读者我要写书评

暂无评论

Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 256-258页

作者： BIAN WeiHao & HUANG Li Department of physics and Institute of Theoretical physics,Nanjing normal university,Nanjing 210097,china Department of physics and Institute of Theoretical physics Nanjing Normal University Nanjing China

For a sample of 33 narrow-line Seyfert 1 galaxies(NLS1s)(z<0.1) from the Sloan Digital Sky Survey,we investigate their *** find that 24 NLS1s show clear bar structure and 9 NLS1s show no bar *** bar frequency in this ... 详细信息

For a sample of 33 narrow-line Seyfert 1 galaxies(NLS1s)(z4 NLS1s show clear bar structure and 9 NLS1s show no bar *** bar frequency in this NLS1s sample is about 70%.We do not find any difference in the location of NLS1s with or without bars on the MBH-σ* diagram.

关键词： active galaxies bar black hole mass

On solving equations of algebraic sum of equal powers

在线全文

学校读者我要写书评

暂无评论

Science china Mathematics 2006年第9期49卷 1153-1157页

作者： WANG Xinghua & YANG Shijun Department of Mathematics, Zhejiang university, Hangzhou 310028, china Department of Mathematics, Hangzhou normal college, Hangzhou 310036, china Department of Mathematics Zhejiang University Hangzhou China Department of Mathematics Hangzhou Normal College Hangzhou China

It is well known that a system of equations of sum of equal powers can be converted to an algebraic equation of higher degree via Newton's identities. This is the Viete-Newton theorem. This work reports the generalizations of the Viete-Newton theorem to a system of equations of algebraic sum of equal powers. By exploiting some facts from algebra and combinatorics,it is shown that a system of equations of algebraic sum of equal powers can be converted in a closed form to two algebraic equations, whose degree sum equals the number of unknowns of the system of equations of algebraic sum of equal powers.

关键词： algebraic sum of equal powers, Newton's identities, system of equations,roots of a polynomial.

Isomerization of B_6,B_6^- and B_6^+ clusters

在线全文

学校读者我要写书评

暂无评论

Science china Chemistry 2010年第1期53卷 202-209页

作者： WEI GongMin1,PU ZhiFeng2,ZOU Rong3,LI GuoLiang2,3 & LUO Qiong2,3 1Department of physics,Capital normal university,Beijing 100048,china 2State Key Laboratory of Explosion Science and technology Beijing Institute of technology,Beijing 100081,china 3Center for Computational Quantum Chemistry,South china normal university,Guangzhou 510631,china Department of physics Capital Normal University Beijing China State Key Laboratory of Explosion Science and technology Beijing Institute of Technology Beijing China Center for Computational Quantum Chemistry South China Normal University Guangzhou China

The interconversions between isomers with the same spin multiplicity of neutral B6 and charged B6-and B6+ clusters have been investigated at the B3LYP/6-311+G level of theory,including determination of the minimum energy pathways with transition states connecting the corresponding reactants and *** dynamic calculations,26 isomers were optimized,including 11 novel *** order to further refine the energies,single-point B3LYP/6-311+G(3df) calculations were carried out on the corresponding B3LYP/6-311+G geometries of all isomers of B6,B6-and B6+ and the corresponding isomerization transition *** stability of each isomer of B6(singlet and triplet states),B6-(doublet state) and B6+(doublet state) was analyzed from both thermodynamic and dynamic viewpoints.

关键词： B6 transition state intrinsic reaction coordinate barrier height

On 3-colorability of planar graphs without adjacent short cycles

在线全文

学校读者我要写书评

暂无评论

Science china Mathematics 2010年第4期53卷 1129-1132页

作者： WANG YingQian 1,MAO XiangHua 1,LU HuaJing 2 & WANG WeiFan 1 1 college of Mathematics,physics and Information Engineering,Zhejiang normal university,Jinhua 321004,china 2 college of Basic Science,Ningbo Dahongying university,Ningbo 315175,china college of Mathematics Physics and Information Engineering Zhejiang Normal University Jinhua China college of Basic Science Ningbo Dahongying University Ningbo China

A short cycle means a cycle of length at most *** this paper,we prove that planar graphs without adjacent short cycles are *** improves a result of Borodin et al.(2005).

关键词： planar graph coloring extension cycle