We report a reconstruction method for fast-fission events in 25 MeV/u^(86)Kr +^(208)Pb reactions at the Compact Spectrometer for Heavy Ion Experiment(CSHINE). The fission fragments(FFs) are measured using three large-...We report a reconstruction method for fast-fission events in 25 MeV/u^(86)Kr +^(208)Pb reactions at the Compact Spectrometer for Heavy Ion Experiment(CSHINE). The fission fragments(FFs) are measured using three large-area parallel-plate avalanche counters, which can deliver the position and arrival timing information of the fragments. The start timing information is provided by the radio frequency of the cyclotron. Fission events were reconstructed using the velocities of the two FFs. The broadening of both the velocity distribution and azimuthal difference of the FFs decreases with the folding angle, in accordance with the picture that fast fission occurs. The anisotropic angular distribution of the fission axis also consistently reveals the dynamic features of fission events.展开更多
The kinetics and the mechanism of the formation reactions of M(PnAO)^(2+)(M=Ni,Co,Cu)were studied with UV Spectrophotometer and Stopped Flow Spectrophotometer and a three steps mechanism was suggested.
The acrosome reaction of sperm was induced by calcium ionophore A 23187.The letionship between some ions and acrosome reaction by removing Na+ from the medium.or by adding angtagonist of K+.TEA chloride,or antagonist ...The acrosome reaction of sperm was induced by calcium ionophore A 23187.The letionship between some ions and acrosome reaction by removing Na+ from the medium.or by adding angtagonist of K+.TEA chloride,or antagonist of Ca++,verapamil,or anlagonist of Na+-K+-ATPase,acetyl strophanthithidin is studied.The results show that Na+,H,Ca++ and Na+ pump are necessary.for acrosome reaclion of human sperm.The Ca++ might not enter the sperms through the channel of Ca++.展开更多
Superoxide ion O^-_2 is prepared in aprotic media by carbon gas-diffusion-electrode for the first time. The experimental results indicate that this electrode is superior to carbon plane-electrode in the reaction of O^...Superoxide ion O^-_2 is prepared in aprotic media by carbon gas-diffusion-electrode for the first time. The experimental results indicate that this electrode is superior to carbon plane-electrode in the reaction of O^-_2 with p-bromonitrobenzene. When the gas-diffussion-electrode is used, the yield of the product nitrophenol increases by 20%, and the selectivity of the reaction is nearly doubled as compared with the plane-electrode.展开更多
Reported here are several new calculation methods for the inner-sphere reorganization energy of hydrated metal ions involved in electron transfer processes.It is based on the self-exchange model of reorganization and ...Reported here are several new calculation methods for the inner-sphere reorganization energy of hydrated metal ions involved in electron transfer processes.It is based on the self-exchange model of reorganization and utilizes the more exact potential functions between central metal ion and the inner-sphere ligands.The parameters involved are determined via the spectroscopic and thermodynamic data.The predictions of the inner-sphere reorganization energies from those models agree well with the photoemission experimental results.展开更多
In this paper, the isotopic and isotonic distributions of projectile fragmentation products have been simulated by a modified statistical abrasion-ablation model and the isoscaling behaviour of projectile-like fragmen...In this paper, the isotopic and isotonic distributions of projectile fragmentation products have been simulated by a modified statistical abrasion-ablation model and the isoscaling behaviour of projectile-like fragments has been discussed. The isoscaling parameters α and β have been extracted respectively, for hot fragments before evaporation and cold fragments after evaporation. It looks that the evaporation has stronger effect on α than β. For cold fragments, a monotonic increase of α and |β| with the increase of Z and N is observed. The relation between isoscaling parameter and the change of isospin content is discussed.展开更多
The high spin states of 106pd have been populated through the 100Mo(11B, lp4n)106Pd reaction using a beam energy of 60 MeV provided by the Beijing HI-13 tandem accel- erator at China Institute of Atomic Energy. By a...The high spin states of 106pd have been populated through the 100Mo(11B, lp4n)106Pd reaction using a beam energy of 60 MeV provided by the Beijing HI-13 tandem accel- erator at China Institute of Atomic Energy. By analyzing the V-3' coincidence relation and DCO raios of transitions, 3 rotational bands with 13 new states and 22 new 7 transitions belonging to 106pd were constructed. Bands 2 and 3 with negative parity were supposed to build on the vh1l/297/2 and vh11/2ds/2 configuration, respectively.展开更多
With or without activation or inhibition of metal ion,the power-time curves of amylase catalyzed reaction were determined by a 2277 thermal activity monitor (Sweden). The Michaelis constant ( K ),apparent Michaelis co...With or without activation or inhibition of metal ion,the power-time curves of amylase catalyzed reaction were determined by a 2277 thermal activity monitor (Sweden). The Michaelis constant ( K ),apparent Michaelis constant ( K _m),maximum velocity ( v _m) and apparent maximum velocity ( v _ am ) of amylase catalyzed reaction were obtained using thermokinetic theory and reduced extent method. On the basis of data obtained,the following relationships between K _m and concentration of metal ion ( c ) were established: for inhibitor of Ni 2+ K _m=2.9648×10 -3 -1.3912×10 -4 cR =0.9998for inhibitor of Co 2+ K _m=1.0227×10 -3 +8.2676×10 -6 cR =0.9955for activator of Ca 2+ K _m=1.0630×10 -7 c 2-1.8311×10 -6 c +9.3058×10 -6 R =0.9999for activator of Li + K _m=5.6300×10 -8 c 2-1.5329×10 -6 c +1.2662×10 -5 R =0.9999 The K _m- c relationships show a strenuous inhibitory effect for Ni 2+ and a strenuous active effect for Ca 2+ .展开更多
The negative secondary ion mass spectrometry,in combination with the stereoselective derivatizations with substituted boronic acid RB(OH)_2,was used in the analysis of fourteen oligosac- charides.The mass spectra of t...The negative secondary ion mass spectrometry,in combination with the stereoselective derivatizations with substituted boronic acid RB(OH)_2,was used in the analysis of fourteen oligosac- charides.The mass spectra of the derivatives provide information on their linkage Positions and iso- merism of the individual monoscaccharide units.The results indicated that among the derivatives of the oligosaccharides analyzed,those with 1—4 and 1—6 linkages all presented the ion peaks at m/z 287,sometimes one more peak at m/z 449.Furthermore,a relationship was found between the linkage positions and the intensity orders of the derivative ions.Finally,the derivatives of the disaccharides with a galactose presented an intense ion peak at m/z 347,and those of oligosaccharides with 1—6 linkage to a galactose at terminal presented the ion at m/z 317.In the case of oligosaccharides with a fructose residue,characteristic ion of m/z 155 was produced.The conditions of stereoselective derivatizations and mass spectrometry were studied,in order to obtain a better reproducibility of the mass spectra.展开更多
Heavy ion collisions near the Fermi energy produce a‘freezout’region where fragments appear and later decay,emitting mainly neutrons,protons,alpha particles,and gamma rays.These decay products carry information abou...Heavy ion collisions near the Fermi energy produce a‘freezout’region where fragments appear and later decay,emitting mainly neutrons,protons,alpha particles,and gamma rays.These decay products carry information about the decaying nuclei.Fragmentation events may result in high yields of boson particles,especially alpha particles,and may carry important information about the nuclear Bose Einstein condensate(BEC).We study‘in medium’fourαcorrelations and link them to the‘fission’of 16O in two 8Be in the ground state or 12C*(Hoyle state)+α.Using novel techniques for the correlation functions,we confirm the resonance of 16O at 15.2 MeV excitation energy,and the possibility of a lower resonance,close to 14.72 MeV.The latter resonance is the result of allαparticles having 92 keV relative kinetic energies.展开更多
Using the isospin-dependent quantum molecular dynamics model, the entropy of an intermediate-energy heavy ion collision system after the reaction and the number of deuteronlike and protonlike particles produced in the...Using the isospin-dependent quantum molecular dynamics model, the entropy of an intermediate-energy heavy ion collision system after the reaction and the number of deuteronlike and protonlike particles produced in the collision is calculated. In the collision, different parameters are used and the mass number used here is from40 to 93 at incident energy from 150 MeV to 1050 MeV. We build a new model in which the density distribution of the reaction product is used to calculate the size of the entropy. The entropy calculated with this model is in good agreement with experimental values. Our data reveals that with the increase of the neutron-proton ratio and impact parameter, the entropy of the reaction system decreases, and it increases with the increase of system mass and reaction energy.展开更多
In this work, the neutron radiation field at Heavy Ion Research Facility in Lanzhou (HIRFL) was investigated. Total neutron yields, spectra and angular distributions in the bombardment of various thick targets by 12...In this work, the neutron radiation field at Heavy Ion Research Facility in Lanzhou (HIRFL) was investigated. Total neutron yields, spectra and angular distributions in the bombardment of various thick targets by 12C and ^18O ions with energies up to 75 MeV/u were obtained using the activation method. The neutron dose equivalent rates of 60 MeV/u ^18O on various thick targets at different angles were measured with a modified A-B remmeter. Our results are compared with those of other reports.展开更多
Despite carbonaceous materials are widely employed as commercial negative electrodes for lithium ion battery, an urge requirement for new electrode materials that meet the needs of high energy density, long cycle life...Despite carbonaceous materials are widely employed as commercial negative electrodes for lithium ion battery, an urge requirement for new electrode materials that meet the needs of high energy density, long cycle life, low cost and safety is still underway. A number of cobalt-based compounds(Co(OH)_2, Co_3O_4, CoN, CoS,CoP, NiCo_2O_4, etc.) have been developed over the past years as promising anode materials for lithium ion batteries(LIBs) due to their high theoretical capacity, rich redox reaction and adequate cyclability. The LIBs performances of the cobalt-based compounds have been significantly improved in recent years, and it is anticipated that these materials will become a tangible reality for practical applications in the near future. However, the different types of cobalt-based compounds will result in diverse electrochemical performance. This review briefly analyzes recent progress in this field, especially highlights the synthetic approaches and the prepared nanostructures of the diverse cobalt-based compounds and their corresponding performances in LIBs, including the storage capacity, rate capability, cycling stability and so on.展开更多
To meet the ever-increasing energy demands, advanced electrode materials are strongly requested for the exploration of advanced energy storage and conversion technologies, such as Li-ion batteries, Li-S batteries, Li-...To meet the ever-increasing energy demands, advanced electrode materials are strongly requested for the exploration of advanced energy storage and conversion technologies, such as Li-ion batteries, Li-S batteries, Li-]Zn-air batteries, supercapacitors, dye-sensitized solar cells, and other electrocatalysis process (e.g., oxygen reductionlevolution reaction, hydrogen evolution reaction). Transition metal chalcogenides (TMCs, Le., sulfides and selenides) are forcefully considered as an emerging candidate, owing to their unique physical and chemical properties. Moreover, the integration of TMCs with conductive graphene host has enabled the significant improvement of electrochemical performance of devices. In this review, the recent research progress on TMC]graphene composites for applications in energy storage and conversion devices is summarized. The preparation process of TMC]graphene nanocomposites is also included. In order to promote an in-depth understanding of performance improvement for TMC/graphene materials, the operating principle of various devices and technologies are briefly presented. Finally, the perspectives are given on the design and construction of advanced electrode materials.展开更多
基金supported by the National Natural Science Foundation of China(Nos.11875174,11961131010,and 11961141004)the Polish National Science Center(No.2018/30/Q/ST2/00185)。
文摘We report a reconstruction method for fast-fission events in 25 MeV/u^(86)Kr +^(208)Pb reactions at the Compact Spectrometer for Heavy Ion Experiment(CSHINE). The fission fragments(FFs) are measured using three large-area parallel-plate avalanche counters, which can deliver the position and arrival timing information of the fragments. The start timing information is provided by the radio frequency of the cyclotron. Fission events were reconstructed using the velocities of the two FFs. The broadening of both the velocity distribution and azimuthal difference of the FFs decreases with the folding angle, in accordance with the picture that fast fission occurs. The anisotropic angular distribution of the fission axis also consistently reveals the dynamic features of fission events.
文摘The kinetics and the mechanism of the formation reactions of M(PnAO)^(2+)(M=Ni,Co,Cu)were studied with UV Spectrophotometer and Stopped Flow Spectrophotometer and a three steps mechanism was suggested.
文摘The acrosome reaction of sperm was induced by calcium ionophore A 23187.The letionship between some ions and acrosome reaction by removing Na+ from the medium.or by adding angtagonist of K+.TEA chloride,or antagonist of Ca++,verapamil,or anlagonist of Na+-K+-ATPase,acetyl strophanthithidin is studied.The results show that Na+,H,Ca++ and Na+ pump are necessary.for acrosome reaclion of human sperm.The Ca++ might not enter the sperms through the channel of Ca++.
文摘Superoxide ion O^-_2 is prepared in aprotic media by carbon gas-diffusion-electrode for the first time. The experimental results indicate that this electrode is superior to carbon plane-electrode in the reaction of O^-_2 with p-bromonitrobenzene. When the gas-diffussion-electrode is used, the yield of the product nitrophenol increases by 20%, and the selectivity of the reaction is nearly doubled as compared with the plane-electrode.
基金Supported by the Natural Science Foundation of Shandong Province
文摘Reported here are several new calculation methods for the inner-sphere reorganization energy of hydrated metal ions involved in electron transfer processes.It is based on the self-exchange model of reorganization and utilizes the more exact potential functions between central metal ion and the inner-sphere ligands.The parameters involved are determined via the spectroscopic and thermodynamic data.The predictions of the inner-sphere reorganization energies from those models agree well with the photoemission experimental results.
基金Project supported in part by the Shanghai Development Foundation for Science and Technology of China (Crant Nos 05XD14021 and 03QA14066), the National Natural Science Foundation of China (Grant Nos 10328259, 10135030, 10405032, 10405033 and 10475108), the Major State Basic Research Development Program of China (Contract No G200077404).
文摘In this paper, the isotopic and isotonic distributions of projectile fragmentation products have been simulated by a modified statistical abrasion-ablation model and the isoscaling behaviour of projectile-like fragments has been discussed. The isoscaling parameters α and β have been extracted respectively, for hot fragments before evaporation and cold fragments after evaporation. It looks that the evaporation has stronger effect on α than β. For cold fragments, a monotonic increase of α and |β| with the increase of Z and N is observed. The relation between isoscaling parameter and the change of isospin content is discussed.
基金supported by the Major State Basic Research Development Program (2007CB815000)by National Natural Science Foundation of China (Nos. 11075214,10927507, 10975191, 10675171, 10105015, 10375092, 10575133, 11175259)
文摘The high spin states of 106pd have been populated through the 100Mo(11B, lp4n)106Pd reaction using a beam energy of 60 MeV provided by the Beijing HI-13 tandem accel- erator at China Institute of Atomic Energy. By analyzing the V-3' coincidence relation and DCO raios of transitions, 3 rotational bands with 13 new states and 22 new 7 transitions belonging to 106pd were constructed. Bands 2 and 3 with negative parity were supposed to build on the vh1l/297/2 and vh11/2ds/2 configuration, respectively.
基金ProjectsupportedbytheNaturalScienceFoundationofShandongProvince (No .Y2 0 0 0B0 3 )
文摘With or without activation or inhibition of metal ion,the power-time curves of amylase catalyzed reaction were determined by a 2277 thermal activity monitor (Sweden). The Michaelis constant ( K ),apparent Michaelis constant ( K _m),maximum velocity ( v _m) and apparent maximum velocity ( v _ am ) of amylase catalyzed reaction were obtained using thermokinetic theory and reduced extent method. On the basis of data obtained,the following relationships between K _m and concentration of metal ion ( c ) were established: for inhibitor of Ni 2+ K _m=2.9648×10 -3 -1.3912×10 -4 cR =0.9998for inhibitor of Co 2+ K _m=1.0227×10 -3 +8.2676×10 -6 cR =0.9955for activator of Ca 2+ K _m=1.0630×10 -7 c 2-1.8311×10 -6 c +9.3058×10 -6 R =0.9999for activator of Li + K _m=5.6300×10 -8 c 2-1.5329×10 -6 c +1.2662×10 -5 R =0.9999 The K _m- c relationships show a strenuous inhibitory effect for Ni 2+ and a strenuous active effect for Ca 2+ .
基金Project supported by the National Natural Science Foundation of China
文摘The negative secondary ion mass spectrometry,in combination with the stereoselective derivatizations with substituted boronic acid RB(OH)_2,was used in the analysis of fourteen oligosac- charides.The mass spectra of the derivatives provide information on their linkage Positions and iso- merism of the individual monoscaccharide units.The results indicated that among the derivatives of the oligosaccharides analyzed,those with 1—4 and 1—6 linkages all presented the ion peaks at m/z 287,sometimes one more peak at m/z 449.Furthermore,a relationship was found between the linkage positions and the intensity orders of the derivative ions.Finally,the derivatives of the disaccharides with a galactose presented an intense ion peak at m/z 347,and those of oligosaccharides with 1—6 linkage to a galactose at terminal presented the ion at m/z 317.In the case of oligosaccharides with a fructose residue,characteristic ion of m/z 155 was produced.The conditions of stereoselective derivatizations and mass spectrometry were studied,in order to obtain a better reproducibility of the mass spectra.
基金Supported by the National Natural Science Foundation of China(11765014,11865010,11905120,I1605097,U2032146,11421505)the Robert A.Welch Founda-tion(A-1266)+6 种基金the US Department of Energy(DE-FG02-93ER40773)Natural Science Foundation of Inner Mongolia(2018MS01009,20191001)the Chinese Academy of Sciences(CAS)President's International Fellowship Initiative(2015VW A070)the Strategic Priority Research Program of the Chinese Academy of Sci-ences(XDB16,XDPB09)the Program for Young Talents of Science and Technology in Univrities of Inmer Mongolia Autonomous Region(NJYT-18-B21)the Doctoral Seientifie Research Foundation of Inner Mongolia University for Nationalities(BS365.BS400)The Fundamental Research Funds for the Central University(GK201903022)。
文摘Heavy ion collisions near the Fermi energy produce a‘freezout’region where fragments appear and later decay,emitting mainly neutrons,protons,alpha particles,and gamma rays.These decay products carry information about the decaying nuclei.Fragmentation events may result in high yields of boson particles,especially alpha particles,and may carry important information about the nuclear Bose Einstein condensate(BEC).We study‘in medium’fourαcorrelations and link them to the‘fission’of 16O in two 8Be in the ground state or 12C*(Hoyle state)+α.Using novel techniques for the correlation functions,we confirm the resonance of 16O at 15.2 MeV excitation energy,and the possibility of a lower resonance,close to 14.72 MeV.The latter resonance is the result of allαparticles having 92 keV relative kinetic energies.
文摘Using the isospin-dependent quantum molecular dynamics model, the entropy of an intermediate-energy heavy ion collision system after the reaction and the number of deuteronlike and protonlike particles produced in the collision is calculated. In the collision, different parameters are used and the mass number used here is from40 to 93 at incident energy from 150 MeV to 1050 MeV. We build a new model in which the density distribution of the reaction product is used to calculate the size of the entropy. The entropy calculated with this model is in good agreement with experimental values. Our data reveals that with the increase of the neutron-proton ratio and impact parameter, the entropy of the reaction system decreases, and it increases with the increase of system mass and reaction energy.
文摘In this work, the neutron radiation field at Heavy Ion Research Facility in Lanzhou (HIRFL) was investigated. Total neutron yields, spectra and angular distributions in the bombardment of various thick targets by 12C and ^18O ions with energies up to 75 MeV/u were obtained using the activation method. The neutron dose equivalent rates of 60 MeV/u ^18O on various thick targets at different angles were measured with a modified A-B remmeter. Our results are compared with those of other reports.
基金financially supported by the‘‘1000 Talents Recruitment Program’’of Chinese government,University of Science and Technology Beijingthe Fundamental Research Funds for the Central Universities(No.FRF-TP-16-070A1)
文摘Despite carbonaceous materials are widely employed as commercial negative electrodes for lithium ion battery, an urge requirement for new electrode materials that meet the needs of high energy density, long cycle life, low cost and safety is still underway. A number of cobalt-based compounds(Co(OH)_2, Co_3O_4, CoN, CoS,CoP, NiCo_2O_4, etc.) have been developed over the past years as promising anode materials for lithium ion batteries(LIBs) due to their high theoretical capacity, rich redox reaction and adequate cyclability. The LIBs performances of the cobalt-based compounds have been significantly improved in recent years, and it is anticipated that these materials will become a tangible reality for practical applications in the near future. However, the different types of cobalt-based compounds will result in diverse electrochemical performance. This review briefly analyzes recent progress in this field, especially highlights the synthetic approaches and the prepared nanostructures of the diverse cobalt-based compounds and their corresponding performances in LIBs, including the storage capacity, rate capability, cycling stability and so on.
基金supported by the National Key Research and Development Program(Nos.2016YFA0202500,2016YFA0200102)the National Natural Science Foundation of China(No.21676160)China Postdoctoral Science Foundation(No.2017M620049)
文摘To meet the ever-increasing energy demands, advanced electrode materials are strongly requested for the exploration of advanced energy storage and conversion technologies, such as Li-ion batteries, Li-S batteries, Li-]Zn-air batteries, supercapacitors, dye-sensitized solar cells, and other electrocatalysis process (e.g., oxygen reductionlevolution reaction, hydrogen evolution reaction). Transition metal chalcogenides (TMCs, Le., sulfides and selenides) are forcefully considered as an emerging candidate, owing to their unique physical and chemical properties. Moreover, the integration of TMCs with conductive graphene host has enabled the significant improvement of electrochemical performance of devices. In this review, the recent research progress on TMC]graphene composites for applications in energy storage and conversion devices is summarized. The preparation process of TMC]graphene nanocomposites is also included. In order to promote an in-depth understanding of performance improvement for TMC/graphene materials, the operating principle of various devices and technologies are briefly presented. Finally, the perspectives are given on the design and construction of advanced electrode materials.