Studies of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and the PP-wave charmed-strange mesons are performed based on an e+e?e+e?collision data sample corresponding to an integrated luminosity of 567 pb?1 collected with ...Studies of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and the PP-wave charmed-strange mesons are performed based on an e+e?e+e?collision data sample corresponding to an integrated luminosity of 567 pb?1 collected with the BESIII detector at s√=4.600s=4.600 GeV.The processes of e+e?→D+sDˉˉˉˉ?0K?e+e?→Ds+Dˉ?0K?and D+sDˉˉˉˉ0K?Ds+Dˉ0K?are observed for the first time and are found to be dominated by the modes D+sDs1(2536)?Ds+Ds1(2536)?and D+sD?s2(2573)?Ds+Ds2?(2573)?,respectively.The Born cross sections are measured to beσB(e+e?→D+sDˉˉˉˉ?0K?)=(10.1±2.3±0.8)σB(e+e?→Ds+Dˉ?0K?)=(10.1±2.3±0.8)pb andσB(e+e?→D+sDˉˉˉˉ0K?)=(19.4±2.3±1.6)σB(e+e?→Ds+Dˉ0K?)=(19.4±2.3±1.6)pb,and the products of Born cross section and the decay branching fraction are measured to beσB(e+e?→D+sDs1(2536)?+c.c.)?σB(e+e?→Ds+Ds1(2536)?+c.c.)?B(Ds1(2536)?→Dˉˉˉˉ?0K?)=(7.5±1.8±0.7)B(Ds1(2536)?→Dˉ?0K?)=(7.5±1.8±0.7)pb andσB(e+e?→D+sD?s2(2573)?+c.c.)?B(D?s2(2573)?→Dˉˉˉˉ0K?)=σB(e+e?→Ds+Ds2?(2573)?+c.c.)?B(Ds2?(2573)?→Dˉ0K?)=(19.7±2.9±2.0)(19.7±2.9±2.0)pb.For the Ds1(2536)?Ds1(2536)?and D?s2(2573)?Ds2?(2573)?mesons,the masses and widths are measured to be M(Ds1(2536)?)=(2537.7±0.5±3.1)MeV/c2M(Ds1(2536)?)=(2537.7±0.5±3.1)MeV/c2,Γ(Ds1(2536)?)=(1.7±1.2±0.6)Γ(Ds1(2536)?)=(1.7±1.2±0.6)MeV,and M(D?s2(2573)?)=M(Ds2?(2573)?)=(2570.7±2.0±1.7)MeV/c2,(2570.7±2.0±1.7)MeV/c2,Γ(D?s2(2573)?)=(17.2±3.6±1.1)Γ(Ds2?(2573)?)=(17.2±3.6±1.1)MeV.The spin-parity of the D?s2(2573)?Ds2?(2573)?meson is determined to be JP=2+JP=2+.In addition,the processes e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?are searched for using the data samples taken at four(two)center-of-mass energies between 4.416(4.527)and 4.575 GeV,and upper limits at the 90%confidence level on the cross sections are determined.展开更多
Dimensionality and orientation of hexagonal boron nitride(h-BN)nanosheets are promising to create and control their unique properties for diverse applications.However,low-temperature deposition of vertically oriented ...Dimensionality and orientation of hexagonal boron nitride(h-BN)nanosheets are promising to create and control their unique properties for diverse applications.However,low-temperature deposition of vertically oriented h-BN nanosheets is a significant challenge.Here we report on the low-temperature plasma synthesis of maze-like h-BN nanowalls(BNNWs)from a mixture of triethylamine borane(TEAB)and ammonia at temperatures as low as 400℃.The maze-like BNNWs contained vertically aligned stacks of h-BN nanosheets.Wavy h-BN nanowalls with randomly oriented nanocrystalline structure are also fabricated.Simple and effective control of morphological type of BNNWs by the deposition-mperature is demonstrated.Despite the lower synthesis temperature,thermal stability and oxidation resistivity of the maze-like BNNWs are higher than for the wavy nanowalls.The structure and oxidation of the nanowalls was found to be the critical factor for their thermal stability and con trolled luminescence properties.Cytotoxic study dem on strated sign ificant antibacterial effect of both maze-like and wavy h-BN nanowalls against E.coli.The reported results reveal a significant potential of h-BN nanowalls for a broad range of applications from electronics to biomedicine.展开更多
Dear Editor Marine mammals are widely distributed and can be found almost in all coastal waters and coastlines around the world.The interface areas between marine and terrestrial environments provide natural habitats ...Dear Editor Marine mammals are widely distributed and can be found almost in all coastal waters and coastlines around the world.The interface areas between marine and terrestrial environments provide natural habitats for aquatic and semiaquatic mammals as well as for reservoir species of avian influenza viruses (AIV)(Runstadler et al.2013).展开更多
BESIII data show a particular angular distribution for the decay of J/ψJ/ψandψ(2S)ψ(2S)mesons intoΛΛˉˉˉˉΛΛˉandΣ0Σˉˉˉˉ0Σ0Σˉ0 hyperons:the angular distribution of the decayψ(2S)→Σ0Σˉˉˉˉ0ψ(...BESIII data show a particular angular distribution for the decay of J/ψJ/ψandψ(2S)ψ(2S)mesons intoΛΛˉˉˉˉΛΛˉandΣ0Σˉˉˉˉ0Σ0Σˉ0 hyperons:the angular distribution of the decayψ(2S)→Σ0Σˉˉˉˉ0ψ(2S)→Σ0Σˉ0 exhibits an opposite trend with respect to the other three channels:J/ψ→ΛΛˉˉˉˉJ/ψ→ΛΛˉ,J/ψ→Σ0Σˉˉˉˉ0J/ψ→Σ0Σˉ0 andψ(2S)→ΛΛˉˉˉˉψ(2S)→ΛΛˉ.We define a model to explain the origin of this phenomenon.展开更多
由俄罗斯科学院西伯利亚分院Melnikov冻土研究所的V.V.Shepelev教授编写,R.V.Zhang教授编辑的《寒区冻结层上水》(Suprapermafrost Waters in the Cryolithozone)一书已于2011年由俄罗斯新西伯利亚的地球科学学术出版社(Novosibirsk...由俄罗斯科学院西伯利亚分院Melnikov冻土研究所的V.V.Shepelev教授编写,R.V.Zhang教授编辑的《寒区冻结层上水》(Suprapermafrost Waters in the Cryolithozone)一书已于2011年由俄罗斯新西伯利亚的地球科学学术出版社(Novosibirsk:Academic Publishing House"Geo")出版发行.全书分为5章,共130页,包括50幅彩图,17个表格,426条主要参考文献,硬皮封面.针对地球科学界提出的一个新研究领域"寒区水文地质学(cryohydrogeology)",该书介绍了其概念、分类方案、主要影响因素、水的化学组成特性、持水系统的水动力特征以及他们对技术影响的响应等.全书包含了作者及其团队多年来对俄罗斯地区冻结层上水的形成规律、区域边界特征、相变特征等进行系统观测所得到的大量数据,并进行系统分析所得到的研究结果,具有很好的应用参考价值.该专著不但会引起水文地质学和冻土学专家的极大兴趣,而且可以作为主修地质学、地理学、土木工程、水文地质学、冻土学的大学生或研究生的教科书,也可以作为专业人员的参考书籍.展开更多
【正】Objective:To present results of virological study of wild birds inhabiting Western Mongolia. Methods:Over a period of 2003-2008,we isolated 13 influenza A viruses:H1N1,H3N6, H13N8 and H4N6 subtypes.We did not i... 【正】Objective:To present results of virological study of wild birds inhabiting Western Mongolia. Methods:Over a period of 2003-2008,we isolated 13 influenza A viruses:H1N1,H3N6, H13N8 and H4N6 subtypes.We did not isolate any H5N1 subtype,that still cause epizooty in wild birds and poultry.Results:We revealed taxonomic and ecological heterogeneity of the birds involved in maintenance of circulation of influenza viruses in the given territory.Influenza viruses were isolated from birds of 6 orders;among them there are species preferring water and semi-aquatic biotopes,one species preferring dry plain region,and also one species which can inhabit both dry and water biotopes.Conclusions:Representatives of all main orders of Western Mongolia avifauna are involved in support of influenza A virus circulation,highly pathogenic H5N1 influenza viruses were registered in Mongolia thus it’s necessary to continue permanent influenza virus surveillance in wild birds’ populations.展开更多
The influence of shear deformation on the behaviour of Mg and Zn impurities as well asself-interstitial atoms in Al was studied using molecular dynamics method.The profilies of potentialrelief were calculated in dir... The influence of shear deformation on the behaviour of Mg and Zn impurities as well asself-interstitial atoms in Al was studied using molecular dynamics method.The profilies of potentialrelief were calculated in directions of possible migration of interstitials.It was found that under load-ing the location of interstitial atoms may be undefined.It means that the system of determined parti-cles may go into stochastic regime of behaviour.展开更多
基金Supported in part by National Key Basic Research Program of China(2015CB856700)National Natural Science Foundation of China(NSFC)(11335008,11425524,11625523,11635010,11735014)+9 种基金the Chinese Academy of Sciences(CAS)Large-Scale Scientific Facility Program,the CAS Center for Excellence in Particle Physics(CCEPP)Joint Large-Scale Scientific Facility Funds of the NSFC and CAS(U1532257,U1532258,U1732263)CAS Key Research Program of Frontier Sciences(QYZDJ-SSW-SLH003,QYZDJ-SSW-SLH040)100 Talents Program of CASINPAC,Shanghai Key Laboratory for Particle Physics and Cosmology,German Research Foundation DFG under Contracts Nos.Collaborative Research Center CRC 1044,FOR 2359Istituto Nazionale di Fisica Nucleare,Italy,Koninklijke Nederlandse Akademie van Wetenschappen(KNAW)(530-4CDP03)Ministry of Development of Turkey(DPT2006K-120470)National Science and Technology fund,The Swedish Research CouncilU.S.Department of Energy(DE-FG02-05ER41374,DE-SC-0010118,DE-SC-0010504,DE-SC-0012069),University of Groningen(RuG)the Helmholtzzentrum fuer Schwerionenforschung GmbH(GSI),Darmstadt.
文摘Studies of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and the PP-wave charmed-strange mesons are performed based on an e+e?e+e?collision data sample corresponding to an integrated luminosity of 567 pb?1 collected with the BESIII detector at s√=4.600s=4.600 GeV.The processes of e+e?→D+sDˉˉˉˉ?0K?e+e?→Ds+Dˉ?0K?and D+sDˉˉˉˉ0K?Ds+Dˉ0K?are observed for the first time and are found to be dominated by the modes D+sDs1(2536)?Ds+Ds1(2536)?and D+sD?s2(2573)?Ds+Ds2?(2573)?,respectively.The Born cross sections are measured to beσB(e+e?→D+sDˉˉˉˉ?0K?)=(10.1±2.3±0.8)σB(e+e?→Ds+Dˉ?0K?)=(10.1±2.3±0.8)pb andσB(e+e?→D+sDˉˉˉˉ0K?)=(19.4±2.3±1.6)σB(e+e?→Ds+Dˉ0K?)=(19.4±2.3±1.6)pb,and the products of Born cross section and the decay branching fraction are measured to beσB(e+e?→D+sDs1(2536)?+c.c.)?σB(e+e?→Ds+Ds1(2536)?+c.c.)?B(Ds1(2536)?→Dˉˉˉˉ?0K?)=(7.5±1.8±0.7)B(Ds1(2536)?→Dˉ?0K?)=(7.5±1.8±0.7)pb andσB(e+e?→D+sD?s2(2573)?+c.c.)?B(D?s2(2573)?→Dˉˉˉˉ0K?)=σB(e+e?→Ds+Ds2?(2573)?+c.c.)?B(Ds2?(2573)?→Dˉ0K?)=(19.7±2.9±2.0)(19.7±2.9±2.0)pb.For the Ds1(2536)?Ds1(2536)?and D?s2(2573)?Ds2?(2573)?mesons,the masses and widths are measured to be M(Ds1(2536)?)=(2537.7±0.5±3.1)MeV/c2M(Ds1(2536)?)=(2537.7±0.5±3.1)MeV/c2,Γ(Ds1(2536)?)=(1.7±1.2±0.6)Γ(Ds1(2536)?)=(1.7±1.2±0.6)MeV,and M(D?s2(2573)?)=M(Ds2?(2573)?)=(2570.7±2.0±1.7)MeV/c2,(2570.7±2.0±1.7)MeV/c2,Γ(D?s2(2573)?)=(17.2±3.6±1.1)Γ(Ds2?(2573)?)=(17.2±3.6±1.1)MeV.The spin-parity of the D?s2(2573)?Ds2?(2573)?meson is determined to be JP=2+JP=2+.In addition,the processes e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?are searched for using the data samples taken at four(two)center-of-mass energies between 4.416(4.527)and 4.575 GeV,and upper limits at the 90%confidence level on the cross sections are determined.
基金Russian Foundation for Basic Research and the government of the Novosibirsk region of the Russian Federation(No.18-43-543003).
文摘Dimensionality and orientation of hexagonal boron nitride(h-BN)nanosheets are promising to create and control their unique properties for diverse applications.However,low-temperature deposition of vertically oriented h-BN nanosheets is a significant challenge.Here we report on the low-temperature plasma synthesis of maze-like h-BN nanowalls(BNNWs)from a mixture of triethylamine borane(TEAB)and ammonia at temperatures as low as 400℃.The maze-like BNNWs contained vertically aligned stacks of h-BN nanosheets.Wavy h-BN nanowalls with randomly oriented nanocrystalline structure are also fabricated.Simple and effective control of morphological type of BNNWs by the deposition-mperature is demonstrated.Despite the lower synthesis temperature,thermal stability and oxidation resistivity of the maze-like BNNWs are higher than for the wavy nanowalls.The structure and oxidation of the nanowalls was found to be the critical factor for their thermal stability and con trolled luminescence properties.Cytotoxic study dem on strated sign ificant antibacterial effect of both maze-like and wavy h-BN nanowalls against E.coli.The reported results reveal a significant potential of h-BN nanowalls for a broad range of applications from electronics to biomedicine.
基金RFBR (research project No 17-04-01919)the National Key Research and Development Project of China (2016YFE0205800)+1 种基金the National Science and Technology Major Project (2016ZXI0004222)mtramural special grants for influenza virus research from the Chinese Academy of Sciences (KJZD-EW-L15).YB is supported by the Youth Innovation Promotion Association of Chinese Academy of Sciences (CAS) (2017122).WS was supported by the Tmshan Scholars program of Shandong Province (ts201511056).
文摘Dear Editor Marine mammals are widely distributed and can be found almost in all coastal waters and coastlines around the world.The interface areas between marine and terrestrial environments provide natural habitats for aquatic and semiaquatic mammals as well as for reservoir species of avian influenza viruses (AIV)(Runstadler et al.2013).
基金Project supported by Russian Foundation for Basic Research (12-08-91150-GFEN_a), National Natural Science Foundation of China (51222701, 51207154, 51211120183), National Basic Research Program of China (973 Program) (20llCB209402), Opening Project of State Key Laboratory of Electrical Insulation and Power Equipment in Xi'an Jiaotong University (EIPEI2204), Chinese Academy of Sciences Visiting Professorship for Senior International Scientists (2012TtG0021).
基金Among the authors, Heckel coordinated and compiled information from all authors and established the correlations Barrick and Board- man provided conodont information for the Midcontinent+6 种基金 Work and Boardman provided ammonoid information for the Midcontinent and perspective on ammonoids reported elsewhere Alekseev and Goreva provided information for correlations in the Moscow region and Dalniy Tyulkas in the Urals Isakova provided information on critical fusulinids in eastern Europe Nemyrovska provided con- odont and cycle-scale information for correlations in the Donets Basin Ueno provided fusulinid information for the Donets Basin Villa chaired the task group that is dealing with this stage boundary, and provided perspective on fusulinid information. We thank all other members of the SCCS Task Group on the Kasimovian-Gzhe- lian Boundary for providing information, thoughtful correspondence and discussions at meetings, particularly V.I. Davydov and V.V. Chernykh who provided information on fusulinids and conodonts in the Usolka and Nikolsky sections in the southern Urals, and along with H.C. Forke, made helpful comments on the manuscript other task group members include A. V. Dzhenchuraeva, B. Fohrer, O.L. Kossovaya, L.L. Lambert, C.A. Mendez, M.L. Martinez Chacon, L.C. Sanchez de
Posada, S.T. Remizova, E. Sammankassou, and G.P. Wahlman.
文摘BESIII data show a particular angular distribution for the decay of J/ψJ/ψandψ(2S)ψ(2S)mesons intoΛΛˉˉˉˉΛΛˉandΣ0Σˉˉˉˉ0Σ0Σˉ0 hyperons:the angular distribution of the decayψ(2S)→Σ0Σˉˉˉˉ0ψ(2S)→Σ0Σˉ0 exhibits an opposite trend with respect to the other three channels:J/ψ→ΛΛˉˉˉˉJ/ψ→ΛΛˉ,J/ψ→Σ0Σˉˉˉˉ0J/ψ→Σ0Σˉ0 andψ(2S)→ΛΛˉˉˉˉψ(2S)→ΛΛˉ.We define a model to explain the origin of this phenomenon.
基金Supported by National Key Basic Research Program of China(2015CB856700) National Natural Science Foundation of China(NSFC)(11235011,11335008,11425524,11625523,11635010)+13 种基金 the Chinese Academy of Sciences(CAS)Large-Scale Scientific Facility Program the CAS Center for Excellence in Particle Physics(CCEPP) Joint Large-Scale Scientific Facility Funds of the NSFC CAS(U1332201,U1532257,U1532258) CAS Key Research Program of Frontier Sciences(QYZDJ-SSW-SLH003,QYZDJ-SSW-SLH040) 100 Talents Program of CAS National 1000 Talents Program of China,INPAC Shanghai Key Laboratory for Particle Physics and Cosmology,German Research Foundation DFG under Contracts Nos.Collaborative Research Center CRC 1044,FOR 2359 Istituto Nazionale di Fisica Nucleare,Italy,Koninklijke Nederlandse Akademie van Wetenschappen(KNAW)(530-4CDP03) Ministry of Development of Turkey(DPT2006K-120470) National Science and Technology fund The Swedish Research Council,U.S.Department of Energy(DEFG02-05ER41374,DE-SC-0010118,DE-SC-0010504,DE-SC-0012069) University of Groningen(RuG) and the Helmholtzzentrum fuer Schwerionenforschung GmbH(GSI) Darmstadt,WCU Program of National Research Foundation of Korea(R32-2008-000-10155-0)
文摘由俄罗斯科学院西伯利亚分院Melnikov冻土研究所的V.V.Shepelev教授编写,R.V.Zhang教授编辑的《寒区冻结层上水》(Suprapermafrost Waters in the Cryolithozone)一书已于2011年由俄罗斯新西伯利亚的地球科学学术出版社(Novosibirsk:Academic Publishing House"Geo")出版发行.全书分为5章,共130页,包括50幅彩图,17个表格,426条主要参考文献,硬皮封面.针对地球科学界提出的一个新研究领域"寒区水文地质学(cryohydrogeology)",该书介绍了其概念、分类方案、主要影响因素、水的化学组成特性、持水系统的水动力特征以及他们对技术影响的响应等.全书包含了作者及其团队多年来对俄罗斯地区冻结层上水的形成规律、区域边界特征、相变特征等进行系统观测所得到的大量数据,并进行系统分析所得到的研究结果,具有很好的应用参考价值.该专著不但会引起水文地质学和冻土学专家的极大兴趣,而且可以作为主修地质学、地理学、土木工程、水文地质学、冻土学的大学生或研究生的教科书,也可以作为专业人员的参考书籍.
文摘 【正】Objective:To present results of virological study of wild birds inhabiting Western Mongolia. Methods:Over a period of 2003-2008,we isolated 13 influenza A viruses:H1N1,H3N6, H13N8 and H4N6 subtypes.We did not isolate any H5N1 subtype,that still cause epizooty in wild birds and poultry.Results:We revealed taxonomic and ecological heterogeneity of the birds involved in maintenance of circulation of influenza viruses in the given territory.Influenza viruses were isolated from birds of 6 orders;among them there are species preferring water and semi-aquatic biotopes,one species preferring dry plain region,and also one species which can inhabit both dry and water biotopes.Conclusions:Representatives of all main orders of Western Mongolia avifauna are involved in support of influenza A virus circulation,highly pathogenic H5N1 influenza viruses were registered in Mongolia thus it’s necessary to continue permanent influenza virus surveillance in wild birds’ populations.
文摘 The influence of shear deformation on the behaviour of Mg and Zn impurities as well asself-interstitial atoms in Al was studied using molecular dynamics method.The profilies of potentialrelief were calculated in directions of possible migration of interstitials.It was found that under load-ing the location of interstitial atoms may be undefined.It means that the system of determined parti-cles may go into stochastic regime of behaviour.