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Observation of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and study of the P-wave DsDs mesons
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作者 麦迪娜 M.N.Achasov +143 位作者 S.Ahmed M.Albrecht M.Alekseev A.Amoroso 安芬芬 安琪 白羽 O.Bakina R.Baldini Ferroli 班勇 K.Begzsuren D.W.Bennett J.V.Bennett N.Berger M.Bertani D.Bettoni F.Bianchi I.Boyko R.A.Briere 蔡浩 蔡啸 A.Calcaterra 曹国富 S.A.Cetin J.Chai 常劲帆 W.L.Chang G.Chelkov 陈刚 陈和生 陈江川 陈玛丽 陈申见 陈元柏 成伟帅 G.Cibinetto F.Cossio 代洪亮 代建平 A.Dbeyssi D.Dedovich 邓子艳 A.Denig I.Denysenko M.Destefanis F.De Mori 丁勇 董超 董静 董燎原 董明义 豆正磊 杜书先 范荆州 方建 房双世 方易 R.Farinelli L.Fava F.Feldbauer G.Felici 封常青 M.Fritsch 傅成栋 付颖 高清 高鑫磊 高原宁 高勇贵 高榛 B.Garillon I.Garzia A.Gilman K.Goetzen 龚丽 龚文煊 W.Gradl M.Greco 谷立民 顾旻皓 顾珊 顾运厅 郭爱强 郭立波 郭如盼 郭玉萍 A.Guskov Z.Haddadi 韩爽 郝喜庆 F.A.Harris 何康林 F.H.Heinsius T.Held 衡月昆 侯治龙 胡海明 胡继峰 胡涛 胡誉 黄光顺 黄金书 黄性涛 黄晓忠 黄智玲 N.Huesken T.Hussain W.Ikegami Andersson W.Imoehl M.Irshad 纪全 姬清平 季晓斌 季筱璐 姜侯兵 江晓山 蒋兴雨 焦健斌 焦铮 金大鹏 金山 金毅 T.Johansson N.Kalantar-Nayestanaki 康晓珅 M.Kavatsyuk 柯百谦 I.K.Keshk T.Khan A.Khoukaz P.Kiese R.Kiuchi R.Kliemt L.Koch O.B.Kolcu B.Kopf M.Kuemmel M.Kuessner A.Kupsc M.Kurth W.Kühn J.S.Lange P.Larin L. 《中国物理C:英文版》 SCIE CAS CSCD 2019年第3期5-16,共12页
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
关键词 cross section P-WAVE D_s MESONS resonance parameters spin-parity BESIII
Evidence for the decays of ∧c^+→∑^+η and ∑^+η’
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作者 麦迪娜 M.N.Achasov +146 位作者 S.Ahmed M.Albrecht M.Aleksee A.Amoroso 安芬芬 安琪 白羽 O.Bakina R. Baldini Ferroli 班勇 K.Begzsuren D.W.Bennett J.V.Bennett N.Berger M.Bertani D.Bettoni F.Bianchi I.Boyko R.A.Briere 蔡浩 蔡啸 O.Cakir A.Calcaterra 曹国富 S.A.Cetin J.Chai 常劲帆 W.L.Chang G.Chelkov 陈刚 陈和生 陈江川 陈玛丽 陈平亮 陈申见 陈元柏 成伟帅 G.Cibinetto F.Cossio 代洪亮 代建平 A.Dbeyssi D.Dedovich 邓子艳 A.Denig I.Denysenko M.Destefanis F.De Mori 丁勇 董超 董静 董燎原 董明义 豆正磊 杜书先 段鹏飞 范荆州 方建 房双世 方易 R.Farinelli L.Fava S.Fegan F.Feldbauer G.Felici 封常青 M.Fritsch 傅成栋 付颖 高清 高鑫磊 高原宁 高勇贵 高榛 B.Garillon I.Garzia A.Gilman K.Goetzen 龚丽 龚文煊 W.Gradl M.Greco 谷立民 顾旻皓 顾运厅 郭爱强 郭立波 郭如盼 郭玉萍 A.Guskov Z.Haddadi 韩爽 郝喜庆 F.A.Harris 何康林 F.H.Heinsius T.Held 衡月昆 侯治龙 胡海明 胡继峰 胡涛 胡誉 黄光顺 黄金书 黄性涛 黄晓忠 黄智玲 T.Hussain N.Hu sken W.Ikegami Andersson M.Irshad 纪全 姬清平 季晓斌 季筱璐 江晓山 蒋兴雨 焦健斌 焦铮 金大鹏 金山 金毅 T.Johansson A.Julin N.Kalantar-Nayestanaki 康晓珅 M.Kavatsyuk 柯百谦 I.K.Keshk T.Khan A.Khoukaz P.Kiese R.Kiuchi R.Kliemt L.Koch O.B.Kolcu B.Kopf M.Kornicer M.Kuemmel M.Kuessner A.Kupsc M.Kurth W.Kuhn J.S.Lange P.Larin L.La 《中国物理C:英文版》 SCIE CAS CSCD 2019年第8期15-23,共9页
We study the hadronic decays of ∧c^+ to the final states ∑^+η and ∑^+η, using an e^+e^- annihilation data sample of 567 pb^-1 taken at a center-of-mass energy of 4.6 GeV with the BESIII detector at the BEPCII col... We study the hadronic decays of ∧c^+ to the final states ∑^+η and ∑^+η, using an e^+e^- annihilation data sample of 567 pb^-1 taken at a center-of-mass energy of 4.6 GeV with the BESIII detector at the BEPCII collider. We find evidence for the decays ∧^+→∑^+η and ∑^+η' and with statistical significance of and , respectively. Normalizing to the reference decays ∧^+→∑^+π^0 and ∑^+ω, we obtain the ratios of the branching fractions B(∧C^+→∑^+η)/V(∧^→∑^+π^0)and B(∧C^+→∑^+η)/B(∧C^+→∑^+ω)to be and , respectively. The upper limits at the 90% confidence level are set to be B(∧C^→∑^+η)/V(∧^+→∑^+π^0)<0.58 and B(∧C^+→∑^+η)/B(∧C^+→∑^+ω)<1.2. Using BESIII measurements of the branching fractions of the reference decays, we determine B(∧C^+→∑^+η)=(0.41±019±0.05)%(<0.68%) and B(∧C^+→∑^+η)=(1.34+0.53+0.19)%(<1.9%). Here, the first uncertainties are statistical and the second systematic. The obtained branching fraction of ∧C^+→∑^+η is consistent with the previous measurement, and the branching fraction of ∧C^+→∑^+η is measured for the first time. 展开更多
关键词 charmed BARYON ∧c^+ DECAYS branching FRACTIONS
Anionic structural effect in liquid–liquid separation of phenol from model oil by choline carboxylate ionic liquids 预览
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作者 Zhiyong Li Ruipeng Li +4 位作者 Xiaoqing Yuan Yuanchao Pei Yuling Zhao Huiyong Wang Jianji Wang 《绿色能源与环境:英文版》 CSCD 2019年第2期131-138,共8页
Phenolic compounds exist in crude oil as pollutants,and their removal is vital important for the refining and further application of oils.In traditional separation approaches,strong acid and strong base have to be use... Phenolic compounds exist in crude oil as pollutants,and their removal is vital important for the refining and further application of oils.In traditional separation approaches,strong acid and strong base have to be used to remove these compounds,which may cause serious environmental problems.In this work,19 kinds of cholinium ionic liquids have been developed to separate phenol from model oil by liquid–liquid extraction.Structural effect of anions of the ionic liquids in the separation is systematically investigated.It is found that depending on the chemical structure of ionic liquids,phenol can be removed from toluene with single-step removal efficiency from 86 to 99%under optimal conditions.The type of substituent groups and the-CH2 number between two carboxylates have obvious effect on the removal efficiency,and more hydrophilic ionic liquids have a stronger extraction performance for phenol.Furthermore,thermodynamic,13C NMR,1H NMR and density functional theory calculations have been performed to characterize the extraction process and to understand the extraction mechanism.It is shown that the extraction of phenol from oil to ionic liquid is a favorable process,and this process is mainly driven by enthalpy change.The formation of the hydrogen bond between anion of the ionic liquid and-OH of phenol is the main driving force for the extraction of phenol from oil to the ionic liquids. 展开更多
关键词 Ionic LIQUID Extraction PHENOL CHOLINE Hydrogen bonding
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Cross-section prediction for isotopes near neutron drip line in 70, 80Zn projectile fragmentation reactions
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作者 魏慧玲 宋一丹 +2 位作者 马春旺 李志宏 苏俊 《中国物理C:英文版》 SCIE CAS CSCD 2019年第7期48-52,共5页
The cross sections for 59,60Ca, recently measured in the 345 A MeV 70Zn+9 Be reaction,were estimated using the FRACS parametrization and an empirical formula,which are in good agreement.The FRACS parametrization and t... The cross sections for 59,60Ca, recently measured in the 345 A MeV 70Zn+9 Be reaction,were estimated using the FRACS parametrization and an empirical formula,which are in good agreement.The FRACS parametrization and the empirical formula are combined to predict the cross sections for extreme calcium isotopes 66,70Ca in the70,80Zn+9 Be reactions at the incident energies of 60,80,and 345 A MeV.The dependence of emperical formula parameters on the reaction system,as well as the incident energy,are discussed.The results indicate that 66,70Ca can be discovered in reactions of 60,80A MeV 80Zn+9 Be.The predicted binding energy for extreme neutron-rich isotopes by the spherical relativistic continuum Hartree-Bogoliubov theory was adopted in the calculation.Hence,the planned Beijing Isotope-Separation-On Line Neutron-Rich Beam Facility(BISOL),which is a third generation radioactive ion beam facility,could provide the opportunity to discover 66,70 Ca and neighboring neutron-drip line nuclei. 展开更多
关键词 neutron-drip line PROJECTILE FRAGMENTATION FRACS cross section Ca-60 Ca-70
Isotope effect and Coriolis coupling effect for the Li + H(D)Cl →LiCl + H(D) reaction
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作者 翟红生 梁广雷 +1 位作者 丁俊霞 刘玉芳 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第5期90-94,共5页
A time-dependent quantum wave packet method is used to investigate the dynamics of the Li+H(D)Cl reaction based on a new potential energy surface (J.Chem.Phys.146 164305 (2017)).The reaction probabilities of the Corio... A time-dependent quantum wave packet method is used to investigate the dynamics of the Li+H(D)Cl reaction based on a new potential energy surface (J.Chem.Phys.146 164305 (2017)).The reaction probabilities of the Coriolis coupled (CC) and centrifugal sudden (CS) calculations,the integral cross sections,the reaction rate constants are obtained.The rate constants of the Li+HCl reaction are within the error bounds at low temperature.A comparison of the CC and CS results reveals that the Coriolis coupling plays an important role in the Li+H(D)Cl reaction.The CC cross sections are larger than the CS results within the entire energy range,demonstrating that the Coriolis coupling effect can more effectively promote the Li+DCl reaction than the Li+HCl reaction.It is found that the isotope effect has a great influence on the title reaction. 展开更多
关键词 ISOTOPE effect CORIOLIS coupling rate CONSTANT quantum wave PACKET
Monopole effects, core excitations, and β decay in the A = 130 hole nuclei near 132Sn
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作者 王韩奎 李志宏 +4 位作者 袁岑溪 陈志强 王宁 秦伟 何翊绮 《中国物理C:英文版》 SCIE CAS CSCD 2019年第5期35-40,共6页
The proton and neutron cross-shell excitations across the Z = 50 shell are investigated in the southwest quadrant of 132Sn by large-scale shell-model calculations with extended pairing and multipole-multipole force. T... The proton and neutron cross-shell excitations across the Z = 50 shell are investigated in the southwest quadrant of 132Sn by large-scale shell-model calculations with extended pairing and multipole-multipole force. The model space allows proton(neutron) core excitations, and both the low-and high-energy states for 130 In are well described, as found by comparison with the experimental data. The monopole effects between the proton orbit and neutron orbit are studied as the new monopole correction that perfectly reproduces the first 1+ level in 130In. The energy interval of proton(neutron) core excitations in 130In lies in the range of 4.5-6.5(2.0-4.1) MeV, and the high energy yrast states are predicted as neutron core excitations. The decays are calculated among the A=130 nuclei of 130In, 130Sn and 130Cd. 展开更多
关键词 MONOPOLE EFFECTS core-excitations β DECAY HOLE NUCLEI
Controllable synthesis of Eu^3+ions doped Zn(OH)F and ZnO micro-structures:Phase,morphology and luminescence property
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作者 Zhiyuan Chen Jingbin Huang +3 位作者 Yanyan Wang Dan Yue Zhenling Wang Jingyang Niu 《中国稀土学报:英文版》 SCIE EI CAS CSCD 2019年第9期955-960,I0003共7页
Eu3+ions doped Zn(OH)F and ZnO micro-structures with specific morphologies were synthesized by a simple hydrothermal method only through altering the addition amount of NH4F and hexamethylenetetramine(HMT).The phase s... Eu3+ions doped Zn(OH)F and ZnO micro-structures with specific morphologies were synthesized by a simple hydrothermal method only through altering the addition amount of NH4F and hexamethylenetetramine(HMT).The phase structure,morphology and luminescence properties of the as-prepared samples were characterized by X-ray powder diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),photoluminescence(PL)spectra and lifetime.The results indicate that the obtained Zn(OH)F:Eu^3+samples possess net-like and dandelion-like morphologies,which have an identical orthorhombic phase structure.It is found that the addition amount of raw materials such as NH4F and HMT plays a critical role for the formation of Zn(OH)F:Eu^3+.If the addition amounts of NH4F or HMT are reduced by half,the hexagonal ZnO:Eu^3+sample with peanut-like morphology can be obtained.Under the excitation of UV light,both the as-prepared Zn(OH)F:Eu^3+and ZnO:Eu^3+samples exhibit the characteristic emission of the doped Eu^3+. 展开更多
关键词 Eu3+ions Doping Zn(OH)F ZnO Luminescence Rare earths
Two-dimensional ferromagnetic materials and related van der Waals heterostructures: a first-principle study 预览
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作者 Baoxing Zhai Juan Du +2 位作者 Xueping Li Congxin Xia Zhongming Wei 《半导体学报:英文版》 EI CAS CSCD 2019年第8期92-99,共8页
Since the successful fabrication of two-dimensional (2D) ferromagnetic (FM) monolayer CrI3 and Cr2Ge2Te6, 2D FM materials are becoming an exciting research topic in condensed matter physics and materials fields, as th... Since the successful fabrication of two-dimensional (2D) ferromagnetic (FM) monolayer CrI3 and Cr2Ge2Te6, 2D FM materials are becoming an exciting research topic in condensed matter physics and materials fields, as they provide a good platform to explore the fundamental physical properties of magnetic materials under 2D limit. In this review, we summarize the theoretical research progress of intrinsic 2D FM materials and related van der Waals heterostructures (vdWHs) including their electronic structures, magnetism, Curie temperature, valley polarization, and band alignment. Moreover, we also summarize recent researches on the methods that used to regulate the above properties of 2D FM materials and vdWHs, such as defects, doping, strain, electric field and interlayer coupling. These studies show that 2D FM materials have broad application prospects in spintronics and valleytronics. However, there are still many problems waiting to be solved on the way to practical application. 展开更多
关键词 2D FM materials HETEROSTRUCTURE CURIE temperature
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Cubic Semisymmetric Graphs of Order 2qp^2
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作者 Xiao-hui HUA Song-tao GUO Li CHEN 《应用数学学报:英文版》 SCIE CSCD 2019年第3期629-637,共9页
A regular edge-transitive graph is said to be semisymmetric if it is not vertex-transitive.Let p be a prime.By Folkman[J.Combin.Theory 3(1967),215–232],there is no cubic semisymmetric graph of order 2p or 2p^2,and by... A regular edge-transitive graph is said to be semisymmetric if it is not vertex-transitive.Let p be a prime.By Folkman[J.Combin.Theory 3(1967),215–232],there is no cubic semisymmetric graph of order 2p or 2p^2,and by Hua et al.[Science in China A 54(2011),1937–1949],there is no cubic semisymmetric graph of order 4p^2.Lu et al.[Science in China A 47(2004),11–17]classified connected cubic semisymmetric graphs of order 6p^2.In this paper,for p>q≥5 two distinct odd primes,it is shown that the sufficient and necessary conditions which a connected cubic edge transitive bipartite graph of order 2qp^2 is semisymmetric. 展开更多
关键词 Bi-Cayley GRAPH EDGE-TRANSITIVE GRAPH semisymmetric GRAPH REGULAR COVERING
X-ray detection based on complementary metal-oxide-semiconductor sensors 预览
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作者 Qian-Qian Cheng Chun-Wang Ma +3 位作者 Yan-Zhong Yuan Fang Wang Fu Jin Xian-Feng Liu 《核技术:英文版》 SCIE CAS CSCD 2019年第1期43-48,共6页
Complementary metal-oxide-semiconductor(CMOS) sensors can convert X-rays into detectable signals;therefore, they are powerful tools in X-ray detection applications. Herein, we explore the physics behind X-ray detectio... Complementary metal-oxide-semiconductor(CMOS) sensors can convert X-rays into detectable signals;therefore, they are powerful tools in X-ray detection applications. Herein, we explore the physics behind X-ray detection performed using CMOS sensors. X-ray measurements were obtained using a simulated positioner based on a CMOS sensor, while the X-ray energy was modified by changing the voltage, current, and radiation time. A monitoring control unit collected video data of the detected X-rays. The video images were framed and filtered to detect the effective pixel points(radiation spots).The histograms of the images prove there is a linear relationship between the pixel points and X-ray energy. The relationships between the image pixel points, voltage, and current were quantified, and the resultant correlations were observed to obey some physical laws. 展开更多
关键词 X-ray detection SIMULATED POSITIONER COMPLEMENTARY METAL-OXIDE-SEMICONDUCTOR sensor Effective PIXEL points
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Selenium-catalyzed oxidative carbonylation of 1,2,3-thiadiazol-5-amine with amines to 1,2,3-thiadiazol-5-ylureas
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作者 Xiaopeng Zhang Shuxiang Dong +2 位作者 Qianqian Ding Xuesen Fan Guisheng Zhang 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第2期375-378,共4页
A facile one-pot, economical approach to 1,2,3-thiadiazol-5-ylureas was developed via seleniumcatalyzed oxidative carbonylation of 1,2,3-thiadiazol-5-amine with a series of amines in one-pot manner in the presence of ... A facile one-pot, economical approach to 1,2,3-thiadiazol-5-ylureas was developed via seleniumcatalyzed oxidative carbonylation of 1,2,3-thiadiazol-5-amine with a series of amines in one-pot manner in the presence of CO and O2. This approach is featured with cheap and easily available raw materials,cheap and reusable catalyst selenium, one-pot procedure, high atomic economy, simple operations and no emission of corrosive wastes. 展开更多
关键词 SELENIUM Oxidative CARBONYLATION 1 2 3-Thiadiazol-5-amine 1 2 3-Thiadiazol-5-ylureas PHASE-TRANSFER CATALYSIS
Enantioselective Conjugate Addition-Protonation of 5H-Oxazol-4-ones and 5-Methylene 1,3-Oxazolidine-2,4-diones: 2,2'-Biphenol-lnduced Diastereoselectivity Switch
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作者 Bohua Lu Shuang Xin +1 位作者 BO Zhu Junbiao Chang 《中国化学:英文版》 SCIE CAS CSCD 2019年第7期689-694,共6页
A synthetic strategy for catalytic asymmetric conjugate addition-protonation and diastereoselective switch between 5H-oxazol-4-ones and 5-methylene 1,3-oxazolidine-2,4-diones was established.An array of chiral conjuga... A synthetic strategy for catalytic asymmetric conjugate addition-protonation and diastereoselective switch between 5H-oxazol-4-ones and 5-methylene 1,3-oxazolidine-2,4-diones was established.An array of chiral conjugate addition-protonation products bearing 1,3-O-heterotertiary-O-heteroquarternary nonadjacent stereocenters were obtained in excellent yields,moderate to good diastereoselectivities,and excellent enantioselectivities (up to 97% yield,11:1 dr,and 98% ee).Induction by 2,2'-biphenol could effectively promote the production of the corresponding diastereoisomers via cycloaddition intermedia. 展开更多
关键词 Conjugate Addition DIASTEREOSELECTIVITY
A Unique Heteronuclear Metal Organic Framework Based on Amino-acid and N-donor Ancillary Ligand: Synthesis, Structure and Characterization 预览
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作者 冯勋 陈海鹏 +3 位作者 贾红 马芬 张道铭 李中军 《结构化学》 SCIE CAS CSCD 2019年第4期597-604,共8页
A novel heteronuclear metal organic framework(MOF) incorporating both transition and alkali metal ions, namely, {(Ni2K2L2·bipy]×6 H2O]×2 H2O}n(1, L = N-phosphonomethyl amino diacetic acid, bipy = 4,4?-d... A novel heteronuclear metal organic framework(MOF) incorporating both transition and alkali metal ions, namely, {(Ni2K2L2·bipy]×6 H2O]×2 H2O}n(1, L = N-phosphonomethyl amino diacetic acid, bipy = 4,4?-dipyridine) has been obtained. Its structure was established by single-crystal X-ray diffraction analysis and further characterized by elemental analysis and IR spectroscopy. The complex crystallizes in orthorhombic system, space group Pccn with a = 14.650(11), b = 36.56(3), c = 7.112(5) ? and V = 3809.3(8) ?3. In this framework, bipy connects adjacent Ni–K heteronuclear coordination units into 1 D railway type chains, which are further propagated into 2 D deck-like array bearing large tunnels through the carboxylic oxygen from N-phosphonomethyl amino diacetic acid. The molar electrical conductivity of heteronuclear complex increases gradually with increasing the temperature. Complex 1 also exhibits strong photoluminescent emission in the visible region. 展开更多
关键词 hetero-nuclear complex N-phosphono-methyl AMINO diacetic acid electrical conductivity emission
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Spatial distribution and filtering efficiency of Daphnia in a deep subtropical reservoir 预览
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作者 ZHANG Man SMYTH Rebecca Ashley +6 位作者 ZHU Weixia ZHANG Li LI Yuncong WANG Yifan LI Xuejun GU Qianhong GAO Yunni 《海洋湖沼学报(英文)》 SCIE CAS CSCD 2019年第4期1277-1288,共12页
Studies of Daphnia distribution and function could help people manage and protect water quality. We investigated how spatial distribution and filtering efficiency of Daphnia in the transition and lacustrine zones of t... Studies of Daphnia distribution and function could help people manage and protect water quality. We investigated how spatial distribution and filtering efficiency of Daphnia in the transition and lacustrine zones of the Nanwan Reservoir (China). Samplings were conducted seasonally for 2 years from six sites in the reservoir. Daphnia abundance and biomass were significantly higher in the lacustrine zone than in the transition zone. Similar composition and biomass of edible phytoplankton were found in the two zones, suggesting that food quantity could not explain high Daphnia distribution in the lacustrine zone. The variations of water velocity and food quality could help explaining Daphnia patchy distribution in the reservoir. On the one hand, rapid water velocity can cause the Daphnia decrement in the transition zone. On the other hand, the ratio of particulate organic carbon (POC) to chlorophyll a (chl a) concentration was significantly higher in the transition zone, indicating more allochthonous material constituted the food source for Daphnia. The lower quality food likely suppressed Daphnia development in the transition zone. A linear regression between Daphnia abundance and Secchi depth (SD) may suggest a cause-effect relationship where increased filtering efficiency was responsible for increased water clarity to some extent. 展开更多
关键词 DAPHNIA LACUSTRINE ZONE transition ZONE water CLARITY Nanwan RESERVOIR
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Lotus-stalk Bi4Ge3O12 as binder-free anode for lithium and sodium ion batteries
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作者 Jianlong Xu Wei Wei +2 位作者 Xu Zhang Lei Liang Maotian Xu 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第6期1341-1345,共5页
Alloyed-type anode materials with high-energy density for lithium and sodium ion batteries attracted much attention of the researchers. However, substantial volume expansion of these materials in the devices during re... Alloyed-type anode materials with high-energy density for lithium and sodium ion batteries attracted much attention of the researchers. However, substantial volume expansion of these materials in the devices during repeated electrochemical process leads to fast capacity fading and hinders their further practical application. Nanotechnology could act as a useful tool to effectively address the issue. Herein, lotus-stalk Bi4Ge3O12 nanosheets vertically grown on the nickel foam (denoted as Bi4Ge3O12 NSs@NF) were prepared via a straight-forward solvothermal method. Benefiting from their three dimensional (3D) conductive framework and two dimensional (2D) lotus-stalk Bi4Ge3O12 nanosheet structure, as anode materials of lithium-ion batteries (LIBs) and sodium-ion batteries (NIBs), the electrochemical performances of Bi4Ge3O12 NSs@NF were greatly enhanced as a result of mitigating the huge volume variations during cycles. The Bi4Ge3O12 NSs@NF electrodes delivered a high reversible capacity of 1033.1 mAh/g for the first cycle and exhibited 68.6%capacity retention of after 88 cycles at 0.10 A/g in the voltage window of 0.01~3.0 V versus Li/Li+. In the test of NIBs, the lotus-stalk Bi4Ge3O12 composite electrodes still stored Na+as high as 332.3 mAh/g at 0.10 A/g over 100 sodiation/desodiation repeating cycles. 展开更多
关键词 Bi4Ge3O12 NANOSHEETS LITHIUM-ION battery Sodium-ion BATTER ANODE
HYPERCYCLIC MULTIPLICATION COMPOSITION OPERATORS ON WEIGHTED BANACH SPACE
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作者 Cui Wang Huiqiang Lu 《应用数学年刊:英文版》 2019年第2期189-196,共8页
This paper characterizes some sufficient and necessary conditions for the hypercyclicity of multiples of composition operators on Hlog,0∞.
关键词 composition OPERATORS HYPERCYCLIC WEIGHTED BANACH space
微波辅助回流法制备桑椹形Na3V2(PO4)2O2F@C正极材料用于高性能钠/锂离子电池(英文)
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作者 侯燕 常焜 +7 位作者 王振宇 顾帅 刘琼 张钧君 程化 张圣麟 常照荣 卢周广 《中国科学:材料科学(英文版)》 CSCD 2019年第4期474-486,共13页
本论文采用快速微波辅助低温回流策略制备了桑椹形Na3V2(PO4)2O2F@C纳米复合材料.研究表明微乳液中的V(acac)3反胶束体系对该自组装结构的形成起到了关键作用.制得的Na3V2(PO4)2O2F晶粒沿着[002]方向生长并被原位包封在碳壳中,形成了高... 本论文采用快速微波辅助低温回流策略制备了桑椹形Na3V2(PO4)2O2F@C纳米复合材料.研究表明微乳液中的V(acac)3反胶束体系对该自组装结构的形成起到了关键作用.制得的Na3V2(PO4)2O2F晶粒沿着[002]方向生长并被原位包封在碳壳中,形成了高度稳定的自组装结构,这不仅有利于Na+/e-的快速迁移,而且能够有效改善电极材料的循环性能并抑制电压衰减.作为钠离子电池正极材料,在0.1 C条件下, Na3V2(PO4)2O2F@C的初始放电容量约为127.9 mA h g-1.在高倍率(20 C)条件下,容量达88.1 mA h g-1, 2000次循环后容量保持率为82.1%.此外,利用非原位X射线衍射, X射线光电子能谱和恒电流间歇滴定技术,初步研究了Na3V2(PO4)2O2F@C在充放电过程中的反应机理和Na+迁移机制.同时,在Li/Na离子混合电池当中, Na3V2(PO4)2O2F@C也表现出了优异的倍率和循环性能.上述微波辅助低温回流合成策略为开发高性能电化学储能材料开辟了新的途径. 展开更多
关键词 sodium and LITHIUM ion batteries CATHODE materials fluorophosphates MICROWAVE-ASSISTED refluxing hierarchical SELF-ASSEMBLY
Trajectory analysis of few-cycle strong field ionization in two-color circularly polarized fields
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作者 黄燕 秦朝朝 +3 位作者 张逸竹 王新成 阎天民 江玉海 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第9期16-21,共6页
Bichromatic circularly polarized fields provide a useful tool to probe the ionization dynamics.In this work, we compare the photoelectron momentum distribution in few-cycle bichromatic field of different helicities.Th... Bichromatic circularly polarized fields provide a useful tool to probe the ionization dynamics.In this work, we compare the photoelectron momentum distribution in few-cycle bichromatic field of different helicities.The spectral features are analyzed with semiclassical trajectories derived from the strong field approximation.In particular, the interference fringes in momentum distribution are investigated by tracking the ionization time and tunneling exits of released photoelectrons.Different types of trajectories that contribute to the interference fringes are elucidated. 展开更多
关键词 strong field IONIZATION SEMICLASSICAL trajectories bicircularly polarized FIELDS PHOTOELECTRON MOMENTUM
Mixed-Type Reverse Order Laws Associated to {1;3;4}-Inverse
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作者 Haiyan ZHANG Chunyuan DENG 《数学研究及应用:英文版》 CSCD 2019年第5期529-539,共11页
In this paper, we study the mixed-type reverse order laws to{1,3,4}-inverses for closed range operators A, B and AB. It is shown that B{1,3,4}A{1,3,4}∈(AB){1,3} if and only if R(A*AB)∈R(B). For every A(134)∈A{1,3,4... In this paper, we study the mixed-type reverse order laws to{1,3,4}-inverses for closed range operators A, B and AB. It is shown that B{1,3,4}A{1,3,4}∈(AB){1,3} if and only if R(A*AB)∈R(B). For every A(134)∈A{1,3,4}, it has (A^(134)AB){1,3,4}A{1,3,4}=(AB){1,3,4} if and only if R(AA*AB) R(AB). As an application of our results, some new characterizations of the mixed-type reverse order laws associated to the Moore-Penrose inverse and the {1,3,4}-inverse are established. 展开更多
关键词 {1 3 4}-inverse REVERSE order LAW GENERALIZED INVERSE block-operator matrix
Binding energies of near proton-drip line Z =22-28 isotopes determined from measured isotopic cross section distributions
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作者 Chun-Wang Ma Yi-Dan Song Hui-Ling Wei 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2019年第1期63-68,共6页
A new method is proposed to determine the binding energy(B)of near proton-drip line isotopes from isotopic cross section distribution.To determine B of Z=22-28 isotopes(with Tz=-2 and-5/2),the lack of cross sections f... A new method is proposed to determine the binding energy(B)of near proton-drip line isotopes from isotopic cross section distribution.To determine B of Z=22-28 isotopes(with Tz=-2 and-5/2),the lack of cross sections for proton-rich isotopes in the 345A MeV ^78Kr+^9Be is overcome by predicting the proton-rich isotopes from a newly discovered scaling phenomenon found in the proton-rich isotopes measured in the 140A MeV ^40,48Ca(^58,64Ni)+^9Be reactions.The cross sections for proton-rich isotopes are verified to exponentially depend on the average binding energy per nucleon,based on which B of the Z=22-28 isotopes with Tz=-2 and-5/2 are determined from cross sections.The determined B of the isotopes are justified from obeying the scaling phenomenon of the difference between the mass of mirror nuclei.The cross sections for the Z=22-28 isotopes with Tz=-1 and-3/2,which in potential can be experimentally studied in mass storage ring,are also predicted. 展开更多
关键词 proton DRIP LINE binding energy mirror nuclei scaling phenomenon
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