摘要：
In this work, a facile method was adopted to synthesize molybdenum disulfide/reduced graphene oxide (MoS_2/rGO) composites through an L-cysteine-assisted hydrothermal technique. The as-prepared MoS_2/ rGO composites were firstly applied as adsorbents for efficient elimination of Pb(II) ions. Batch adsorption experiments showed that the adsorption of Pb(II) on MoS_2/rGO followed pseudo-second-order kinetic model well. The adsorption of Pb(II) was intensely pH-dependent, ionic strength-dependent at pH < 9.0 and ionic strength-independent at pH > 9.0. The presence of humic acid (HA) enhanced Pb(II) adsorption obviously. The MoS_2/rGO composites exhibited excellent adsorption capacity of 384.16 mg g~(-1) at pH 5.0 and T=298.15 K, which was superior to MoS_2 (279.93 mg g~(-1)) and many other adsorbents. The thermodynamic parameters suggested that the adsorption process of Pb(II) on MoS_2/rGO composites was spontaneous (?G~θ < 0) and endothermic (?H~θ > 0). The interaction of Pb(II) and MoS_2/ rGO was mainly dominated by electrostatic attraction and surface complexation between Pb(II) and oxygen-containing functional groups of MoS_2/rGO. This work highlighted the application of MoS_2/rGO as novel and promising materials in the efficient elimination of Pb(II) from contaminated water and industrial effluents in environmental pollution management.
关键词：
Effective mass;Equation of state;Symmetry energy;Neutron-rich matter
摘要：
In this talk, we first briefly review the isospin dependence of the total nucleon effective mass M_J~* inferred from analyzing nucleon-nucleus scattering data within an isospin-dependent non-relativistic optical potential model, and the isospin dependence of the nucleon E-mass M_J~(*,E) obtained from applying the Migdal–Luttinger theorem to a phenomenological single-nucleon momentum distribution in nuclei constrained by recent electron-nucleus scattering experiments. Combining information about the isospin dependence of both the nucleon total effective mass and E-mass, we then infer the isospin dependence of nucleon k-mass using the well-known relation M_J~* = M_J~(*,E)·M_J~(*,k). Implications of the results on the nucleon mean free path in neutron-rich matter are discussed.
作者：
Li, Jing-Chun;Gong, Xue-Yu*;Dong, Jia-Qi;Wang, Jun;Yin, Lan
期刊：
Chinese Physics B,2016年25(4):45201-1-45201-8 ISSN：1674-1056
通讯作者：
Gong, Xue-Yu
作者机构：
[Gong, Xue-Yu; Li, Jing-Chun] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Wang, Jun; Dong, Jia-Qi] Southwestern Inst Phys, POB 432, Chengdu 610041, Peoples R China.;[Yin, Lan] Univ South China, Sch Math & Phys, Hengyang 421001, Peoples R China.
通讯机构：
[Gong, Xue-Yu] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.
关键词：
HL-2M;electron–cyclotron current drive;neoclassical tearing modes;sawtooth
摘要：
The capabilities of current drive, neoclassical tearing mode (NTM) stabilization, and sawtooth control are analyzed for the electron–cyclotron wave (ECW) system in a HL-2M tokamak. Better performance of the upper launcher is demonstrated in comparison with that of a dropped upper launcher, in terms of J_(EC)/J_(bs) for NTM stabilization and I_(ECCD)/(?_ρ(tor))~2 for sawtooth control. 1-MW ECW power is enough for the 3/2 NTM stabilization, and 1.8-MW ECW power is required to suppress 2/1 NTM in a single null divertor equilibrium with 1.2-MA toroidal current with the upper launcher. Optimization simulation of electron–cyclotron current drive (ECCD) is carried out for three mirrors in an equatorial port, indicating that the middle mirror has a good performance compared with the top and bottom mirrors. The results for balanced co-and counter-ECCD in an equatorial port are also presented.
摘要：
Three-dimensional graphene/conducting polymer (3DGCP) composites have received significant attention in recent years due to their unique structures and promising applications in energy storage. With the structural diversity of graphene and π-functional conducting polymers via rich chemical routes, a number of 3DGCP composites with novel structures and attractive performance have been developed. Particularly, the hierarchical porosity, the interactions between graphene and conducting polymers as well as the their synergetic effects within 3DGCP composites can be well combined and elaborated by various synthetic methods, which made 3DGCP composites show unique electrochemical properties and significantly improved performance in energy storage fields compared to other graphenebased composites. In this short review, we present recent advances in 3DGCP composites in developing effective strategies to prepare 3DGCP composites and exploring them as a unique platform for supercapacitors with unprecedented performance. The challenges and future opportunities are also discussed for promotion of further study.
摘要：
In this paper, based on the two-potential approach combining with the isospin dependent nuclear potential, we systematically compare the α preformation probabilities of odd-A nuclei between nuclear isomeric states and ground states. The results indicate that during the process of α particle preforming, the low lying nuclear isomeric states are similar to ground states. Meanwhile, in the framework of single nucleon energy level structure, we find that for nuclei with nucleon number below the magic numbers, the α preformation probabilities of high-spin states seem to be larger than low ones. For nuclei with nucleon number above the magic numbers, the α preformation probabilities of isomeric states are larger than those of ground states.
作者：
Lu Yan-Xia*;Lu Xing-Qiang;Song Xiang;Zhang Bo-Li
期刊：
Chinese Physics B,2011年20(3): 033402-1-033402-5 ISSN：1674-1056
通讯作者：
Lu Yan-Xia
作者机构：
[Lu Xing-Qiang; Zhang Bo-Li; Lu Yan-Xia; Song Xiang] Univ S China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.
通讯机构：
[Lu Yan-Xia] Univ S China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.
关键词：
ion-atom collision;cross section;electron loss
摘要：
Electron-loss cross sections of O~(q+) (q = 1-4) colliding with He, Ne and Ar atoms are measured in the intermediate velocity regime. The ratios of the cross sections of two-electron loss to that of one-electron loss R21 are presented. It is shown that single-channel analysis is not sufficient to explain the results, but that projectile electron loss, electron capture by the projectile and target ionization must be considered together to interpret the experimental data. The screening and antiscreening effects can account for the threshold velocity results, but cannot explain the dependence of the ratio R21 on velocity quantitatively. In general, the effective charge of the target atom increases with velocity increasing because the high-speed projectile ion can penetrate into the inner electronic shell of target atom. Ne and Ar atoms have similar effective charges in this velocity regime, but He atoms have smaller ones at the same velocities due to its smaller nuclear charge
期刊：
Chinese Physics. C,2018年42(4):044102-1-044102-5 ISSN：1674-1137
通讯作者：
Wu, Xi-Jun
作者机构：
[Li, Xiao-Hua; Zhao, Jie-Cheng; Deng, Jun-Gang; Chen, Jiu-Long] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Wu, Xi-Jun] Univ South China, Sch Math & Phys, Hengyang 421001, Peoples R China.;[Li, Xiao-Hua] Univ South China, Cooperat Innovat Ctr Nucl Fuel Cycle Technol & Eq, Hengyang 421001, Peoples R China.;[Li, Xiao-Hua] Hunan Normal Univ, Key Lab Low Dimens Quantum Struct & Quantum Contr, Changsha 410081, Hunan, Peoples R China.
通讯机构：
[Wu, Xi-Jun] Univ South China, Sch Math & Phys, Hengyang 421001, Peoples R China.
关键词：
a decay;~(296)Og;hindrance factor;two-potential approach
摘要：
The present work is a continuation of our previous paper [J.-G. Deng, et al., Chin. Phys. C, 41: 124109 (2017)]. In the present work, the a decay half-life of the unknown nucleus 2960g is predicted within the two-potential approach and the hindrance factors of all 20 even-even nuclei in the same region as ~(296)Og, i.e. proton number 82<Z<126 and neutron number 152<N<184, from ~(250)Cm to ~(294)Og, are extracted. The prediction is 1.09 ms within a factor of 5.12. In addition, based on the latest experimental data, a new set of parameters of a decay hindrance factors for the even-even nuclei in this region, considering the shell effect and proton-neutron interaction, are obtained.
关键词：
Medical radioisotope;Photonuclear simulation;Photon–neutron;Photo-proton;Specific activity;Geant4
摘要：
For simulating more accurately neutron or proton production from photonuclear reactions, a data-based photonuclear reaction simulation algorithm has been developed. Reliable photonuclear cross sections from evaluated or experimental database are chosen as input data. For checking the validity of the use of the data-based photonuclear algorithm, benchmarking simulations are presented in detail. We calculate photonuclear cross sections or reaction yield for ~9Be, ~(48)Ti, ~(133)Cs, and ~(197)Au and compare them with experimental data in the region of incident photon energy below *30 MeV. While Geant4 can hardly reproduce photonuclear experimental data, results obtained from the data-based photonuclear algorithm are found in good agreement with experimental measurements. Potential application in estimation of specific activity of radioisotopes is further discussed. We conclude that the developed data-based photonuclear algorithm is suitable for an accurate prediction of photoninduced neutron or proton productions.
摘要：
The α decay half-life of the unknown nucleus ~(297)Og is predicted within the two-potential approach, and α preformation probabilities of 64 odd-A nuclei in the region of proton numbers 82<Z< 126 and neutron numbers 152<N<184, from ~(251)Cf to ~(295)Og, are extracted. In addition, based on the latest experimental data, a new set of parameters for α preformation probabilities considering the shell effect and proton-neutron interaction are obtained. The predicted α decay half-life of ~(297)Og is 0.16 ms within a factor of 4.97. The predicted spin and parity of the ground states for ~(269)Sg, ~(285)Fl and ~(293)Lv are 3/2~+,3/2~+ and 5/2~+,respectively.
摘要：
Copper-64 is a radioisotope of medical interest that could be used for positron emission tomography imaging and targeted radiotherapy of cancer. In this work, we investigated the possibility of producing the ~(64)Cu isotope through a ~(65)Cu(γ,n) reaction using high-intensity c-beams produced at the Extreme Light Infrastructure- Nuclear Physics facility (ELI-NP). The specific activity for ~(64)Cu was obtained as a function of target geometry, irradiation time, and electron beam energy, which translates into γ-beam energy. Optimized conditions for the generation of ~(64)Cu isotopes at the ELI-NP were discussed. We estimated that an achievable saturation specific activity is of the order of 1-2 mCi/g for thin targets (radius 1-2 mm, thickness 1 cm) and for a γ-beam flux of 10~(11) s~(-1). Based on these results, the ELI-NP could provide great potential for the production of some innovative radioisotopes of medical interest in sufficient quantities suitable for nuclear medicine research.
关键词：
gas electron multiplier;cosmic muon;X-ray;rising time;discrimination
摘要：
Gas electron multiplier (GEM) detectors have been used in cosmic muon scattering tomography and neutron imaging over the last decade. In this work, a triple GEM device with an effective readout area of 10 cm x 10 cm is developed, and a method of discriminating between cosmic muons and X-rays based on rise time is tested. The energy resolution of the GEM detector is tested by ~(55)Fe ray source to prove the GEM detector has a good performance. Analysis of the complete signal-cycles allows us to get the rise time and pulse heights. The experiment result indicates that cosmic muons and X-rays can be discriminated with an appropriate rise time threshold.
摘要：
We propose a slanting collision scheme for Compton scattering of a laser light against a relativistic electron beam. This scheme is suitable to generate an energy-tunable X/γ-ray source. In this paper, we present theoretical study and simulation of the spectral, spatial and temporal characteristics of such a source. We also describe two terms laser-Compton scattering (LCS) experiments at the 100 MeV Linac of Shanghai Institute of Applied Physics, where quasi-monochromatic LCS X-ray energy spectra with peak energies of ～ 30 keV are observed successfully. These preliminary investigations are carried out to understand the feasibility of developing an energy-tunable quasi-monochromatic X/γ-ray source, the future Shanghai Laser Electron Gamma Source.
期刊：
Chinese Physics C,2015年39(5): 053101-1-053101-3 ISSN：1674-1137
通讯作者：
Zhang, ZH
作者机构：
[Zhang Zhen-Hua] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Zhang Zhen-Hua; Lu, Gang] Univ South China, Cooperat Innovat Ctr Nucl Fuel Cycle Technol & Eq, Hengyang 421001, Peoples R China.;[Lu, Gang; Wei Ke-Wei] Henan Univ Technol, Coll Sci, Zhengzhou 450001, Peoples R China.;[Wei Ke-Wei] Anyang Normal Univ, Coll Phys & Elect Engn, Anyang 455002, Peoples R China.
通讯机构：
[Zhang, ZH ] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.
关键词：
X（3872）;mass degeneracy;B meson
摘要：
The spin is an important property of a particle. Although it is unlikely, there is still a possibility that two particles with different spins share similar masses. In this paper, we propose a method to probe this kind of mass degeneracy of particles with different spins. We use the cascade decay B+→X(3872)K+, X(3872)→D+D-to illustrate our method. It can be seen that the possible mass degeneracy of X(3872) can lead to interesting behavior in the corresponding cascade decay.
期刊：
Chinese Physics. C,2016年40(7):076002_01-076002_05 ISSN：1674-1137
通讯作者：
Hu, Bi-Tao;Sun, Zhi-Jia
作者机构：
[Li, Ke; Hu, Bi-Tao; Zhou, Jian-Rong] Lanzhou Univ, Sch Nucl Sci & Technol, Lanzhou 730000, Peoples R China.;[Li, Ke; Zhou, Liang; Xu, Hong; Sun, Zhi-Jia; Yang, Gui-An; Wang, Yan-Feng; Xie, Yu-Guang; Zhou, Jian-Rong] Chinese Acad Sci, Inst High Energy Phys, Beijing 100049, Peoples R China.;[Li, Ke; Zhou, Liang; Xu, Hong; Sun, Zhi-Jia; Yang, Gui-An; Wang, Yan-Feng; Zhou, Jian-Rong] Dongguan Neutron Sci Ctr, Dongguan 523803, Peoples R China.;[Wang, Xiao-Dong] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Xiong, Tao] Sun Yat Sen Univ, Sino French Inst Nucl Engn & Technol, Zhuhai 519082, Peoples R China.
通讯机构：
[Hu, Bi-Tao] Lanzhou Univ, Sch Nucl Sci & Technol, Lanzhou 730000, Peoples R China.;[Sun, Zhi-Jia] Chinese Acad Sci, Inst High Energy Phys, Beijing 100049, Peoples R China.;[Sun, Zhi-Jia] Dongguan Neutron Sci Ctr, Dongguan 523803, Peoples R China.
关键词：
GEM;THGEM;neutron detection;boron convertor;alternative to 3He
摘要：
With new generation neutron sources, traditional neutron detectors cannot satisfy the demands of the applications, especially under high flux. Furthermore, facing the global crisis in ~3He gas supply, research on new types of neutron detector as an alternative to ~3 He is a research hot spot in the field of particle detection. GEM (Gaseous Electron Multiplier) neutron detectors have high counting rate, good spatial and time resolution, and could be one future direction of the development of neutron detectors. In this paper, the physical process of neutron detection is simulated with Geant4 code, studying the relations between thermal conversion efficiency, boron thickness and number of boron layers. Due to the special characteristics of neutron detection, we have developed a novel type of special ceramic nTHGEM (neutron THick GEM) for neutron detection. The performance of the nTHGEM working in different Ar/CO_2 mixtures is presented, including measurements of the gain and the count rate plateau using a copper target X-ray source. A detector with a single nTHGEM has been tested for 2-D imaging using a ~(252) Cf neutron source. The key parameters of the performance of the nTHGEM detector have been obtained, providing necessary experimental data as a reference for further research on this detector.
摘要：
We theoretically investigate the Autler–Townes(AT)splitting in the photoelectron spectrum of four-level ladder K_2 molecule driven by a pump 1-pump 2-probe pulse via employing the time-dependent wave packet approach.The effects of the pump-1 laser intensity and wavelength on AT splitting are studied for the first time.The magnitude of AT splitting increases with increasing the pump-1 laser intensity.The triple splitting with asymmetric profile occurs due to the nonresonant excitation.The triple structure is transformed into a double structure(near-resonant region),and then becomes a peak(far-off resonant region)progressively as the pump-1 laser is detuned from the resonance wavelength,which can be explained in terms of the asymmetric excitation/population of dressed states.The splitting between adjacent peaks and the splitting between the two sideband peaks in the triplet do not change with the pump-1 pulse wavelength.The three peaks shift toward lower energy with the same shift 1/4*△_1 as the pump-1 wavelength changes in near-resonant region.The asymptotic behaviors of AT splitting with the pump-1 laser intensity are interesting in the threshold points of the near-resonant region and the far-off resonant region.
期刊：
Chinese Physics. C,2010年34(4):479-481 ISSN：1674-1137
通讯作者：
Duan Li-Min
作者机构：
[Zhang Jin-Xia; Lu Chen-Gui; Li Zu-Yu; Liu Da; Tang Shu-Wen; Hu Zheng-Guo; Duan Li-Min; Sun You-Mei; Hu Rong-Jiang; Ma Peng; Lu Yan-Xia; Xu Zhi-Guo; Geng Peng] Chinese Acad Sci, Inst Modern Phys, Lanzhou 730000, Peoples R China.;[Lu Chen-Gui; Liu Da; Tang Shu-Wen; Duan Li-Min; Ma Peng; Geng Peng] Chinese Acad Sci, Grad Univ, Beijing 100049, Peoples R China.;[Lu Yan-Xia] Univ S China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Wang Wen-Xin; Zhou Jian-Rong; Yang He-Run] Lanzhou Univ, Sch Nucl Sci & Technol, Lanzhou 730000, Peoples R China.
通讯机构：
[Duan Li-Min] Chinese Acad Sci, Inst Modern Phys, Lanzhou 730000, Peoples R China.
摘要：
A novel Micro-pattern gaseous detector (MPGD), thick GEM with electrodes made of a resistive material (RETGEM) is presented. In this paper we mainly investigate the energy resolution of a RETGEM in Ar+CO_2 with different gas mixtures. The results indicate that an energy resolution 30% in single and double mode can be obtained. The existence of an optimum energy resolution is discussed.
期刊：
Chinese Physics. C,2009年33(11):1006-1009 ISSN：1674-1137
通讯作者：
Lin Jun
作者机构：
[Lin Jun; Li Yu-Lan; Liu Wei; Li Yan; Yu Xiao-Han; Bao Liang-Man] Chinese Acad Sci, Shanghai Inst Appl Phys, Shanghai 201800, Peoples R China.;[Xu Zhong-Yang] Univ S China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[He Wei; Chen Dong-Liang] Chinese Acad Sci, Inst High Energy Phys, Beijing 100049, Peoples R China.
通讯机构：
[Lin Jun] Chinese Acad Sci, Shanghai Inst Appl Phys, Shanghai 201800, Peoples R China.
摘要：
The characteristics of daytime and nighttime suburbs PM_(2.5) in Shanghai were analyzed by synchrotron based X-ray fluorescence during the period of October, 2006 and November, 2007. The mass concentrations of nighttime PM_(2.5) was approximately two times that of daytime PM_(2.5). Some elements, such as Zn, Cu, Mn, C1 were found enriched at night. The local sources might have significant contribution to the nighttime PM_(2.5) pollutions.
期刊：
Chinese Physics Letters,2015年32(3): 032901-1-032901-4 ISSN：0256-307X
通讯作者：
Hu Bi-Tao
作者机构：
[Luo Wen; Wang Xiao-Dong] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Duan Li-Min; Hu Rong-Jiang; Lu Chen-Gui; Zhang Jun-Wei; Yang He-Run] Chinese Acad Sci, Inst Modern Phys, Lanzhou 730000, Peoples R China.;[Hu Bi-Tao; Zhang Chun-Hui; Yang Lei] Lanzhou Univ, Sch Nucl Sci & Technol, Lanzhou 730000, Peoples R China.;[Zhou Jian-Rong] Chinese Acad Sci, Inst High Energy Phys, Beijing 100049, Peoples R China.;[An Lv-Xing] China Petr Logging CO LTD, LWD Logging Ctr, Xian 710000, Peoples R China.
摘要：
A detector for fast neutrons based on a 10 × 10 cm~2 triple gas electron multiplier (GEM) device is developed and tested. A neutron converter, which is a high density polyethylene (HDPE) layer, is combined with the triple GEM detector cathode and placed inside the detector, in the path of the incident neutrons. The detector is tested by obtaining the energy deposition spectrum with an Am Be neutron source in the Institute of Modern Physics (IMP) at Lanzhou. In the present work we report the results of the tests and compare them with those of simulations. The transport of fast neutrons and their interactions with the different materials in the detector are simulated with the GEANT4 code, to understand the experimental results. The detector displays a clear response to the incident fast neutrons. However, an unexpected disagreement in the energy dependence of the response between the simulated and measured spectra is observed. The neutron sources used in our simulation include deuterium-tritium (DT, 14 MeV), deuterium-deuterium (DD, 2.45 MeV), and Am Be sources. The simulation results also show that among the secondary particles generated by the incident neutron, the main contributions to the total energy deposition are from recoil protons induced in hydrogen-rich HDPE or Kapton (GEM material), and activation photons induced by neutron interaction with Ar atoms. Their contributions account for 90% of the total energy deposition. In addition, the dependence of neutron deposited energy spectrum on the composition of the gas mixture is presented.
