作者：
Ni, Zining;Xie, Jinsen*;Wasaye, Muhammad Abdul;Zhang, Erpin;Yu, Tao
期刊：
International Journal of Energy Research,2023年2023 ISSN：0363-907X
通讯作者：
Xie, Jinsen;Yu, T
作者机构：
[Wasaye, Muhammad Abdul; Zhang, Erpin; Xie, Jinsen; Ni, Zining; Yu, Tao] Univ South China, Sch Nucl Sci & Technol, Hengyang, Hunan, Peoples R China.;[Wasaye, Muhammad Abdul; Zhang, Erpin; Xie, Jinsen; Ni, Zining; Yu, Tao] Univ South China, Res Ctr Digital Nucl Reactor Engn & Technol Hunan, Hengyang, Hunan, Peoples R China.;[Xie, Jinsen; Yu, Tao] Univ South China, Sch Nucl Sci & Technol, Hengyang, Hunan, Peoples R China.;[Xie, Jinsen; Yu, Tao] Univ South China, Res Ctr Digital Nucl Reactor Engn & Technol Hunan, Hengyang, Hunan, Peoples R China.
通讯机构：
[Xie, JS; Yu, T ] ;Univ South China, Sch Nucl Sci & Technol, Hengyang, Hunan, Peoples R China.;Univ South China, Res Ctr Digital Nucl Reactor Engn & Technol Hunan, Hengyang, Hunan, Peoples R China.
摘要：
Higher-order neutron fluxes (i.e., higher-order harmonics) are widely applied in perturbation theory and modal kinetics, and they are important for research on the physical characteristics of accelerator-driven subcritical reactors (ADSRs). This paper presents a computational scheme for reconstructing the neutron flux in the steady state according to the biorthogonal properties of the forward and adjoint neutron fluxes, which can be used to analyze how higher-order harmonics affect the steady-state neutron flux under lambda- and prompt alpha-modes. Simulation results indicated that a modal synthesis method based on lambda- and prompt alpha-modes can effectively reconstruct the steady-state neutron flux and core power in an ADSR with a power reconstruction accuracy of within 5%. The higher-order harmonics can be classified into three types according to their physical characteristics: the first type contributes significantly to the steady-state neutron flux, the second type contributes almost nothing to the steady-state neutron flux, and the third type contributes nothing to the steady-state neutron flux. The external neutron source contributes only to specific harmonic expansion orders, which are characterized by significant axial and radial symmetry for both the lambda- and prompt alpha-modes.
通讯机构：
[Yanliang Tan] C;College of Physics and Electronic Engineering , Hengyang Normal University, Hengyang, Hunan Province 421008, China
摘要：
Radon-222 (Rn-222) exhalation rate is vital for estimating radiation risk from many kinds of materials. AlphaGUARD measures the radon concentration based on the ionization chamber principle, which is currently recognized as a reference instrument to measure radon. In China, measurements of radon exhalation rate are performed by AlphaGUARD operated in flow-through mode on a reference device to verify measurement accuracy. These measurements are performed in both open and closed loop. AlphaGUARD can fast rapidly the variation of the radon concentration in the chamber, which is tightly pressed against the surface of the medium to accumulate the exhaled radon. When the model is used to obtain the radon exhalation rate, the radon exhalation rates obtained by nonlinear data fitting on the measured radon concentrations are similar to the reference value of the device. The difference of radon exhalation rate values of six measurements is small.
摘要：
We employ a real-space grids technique to calculate positron annihilation lifetimes with pseudopotentials. This method is based on the two-component of density functional theory (TCDFT), the Hamiltonian operator of the Kohn-Sham equation is discretized on a point grid by the finite difference method (FDM), the positron eigenstates are searched by the conjugate-gradient method (CG) and the positron Kohn-Sham equation is solved by a self-consistent iteration method. We show that the numerical results under this scheme for bulk and monovacancy of positron annihilation lifetimes are in reasonable agreement with the available experimental data. Further-more, all the results of our calculations demonstrate the accuracy and efficiency of the method from different aspects.
作者机构：
[Zhang, Zhen-Hua] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Hunan, Peoples R China.
摘要：
We propose to search for CP violation through the twofold angular distributions in the four-body decays of bottom and charmed hadrons. The two polar angles in the twofold angular distributions are correlated, to which the interferences of intermediate resonances are one important origin. These interferences will leave tracks in the twofold angular distributions, with which the CP violation can be studied. Special attention is paid to the case when all the intermediate resonances are different, which is unique to four-body decays. It is suggested to look for CP violation in four-body decays such as ?0b -> pK-K thorn K- through the analysis of the twofold angular distributions. The method proposed in this paper is also widely applicable to other four-body decays processes.
作者机构：
[Xiao, Detao; Hu, Yihao; Wu, Haibiao; Xiao, DT] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Zhang, Peng; Wang, Baoyi; Cao, Xingzhong; Li, Chong; Wei, Long; Liu, Fuyan; Wei, L; Kuang, Peng; Cao, XZ] Chinese Acad Sci, Inst High Energy Phys, Beijing 100049, Peoples R China.;[Wang, Baoyi; Cao, Xingzhong; Wei, Long; Wei, L; Cao, XZ] Univ Chinese Acad Sci, Beijing 100039, Peoples R China.;[Wu, Haibiao] Univ South China, Affilated Hosp 1, Hengyang 421001, Peoples R China.
通讯机构：
[Wei, L ; Cao, XZ] C;[Xiao, DT ] U;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;Chinese Acad Sci, Inst High Energy Phys, Beijing 100049, Peoples R China.;Univ Chinese Acad Sci, Beijing 100039, Peoples R China.
关键词：
Monte Carlo simulation;multi-elemental targets;muonic x-ray;distribution of muonic atoms
摘要：
Determining the distribution of muonic atoms is essential for & mu;-X ray imaging. In this study, the generation and de-excitation of muonic atoms in multi-elemental targets were simulated using the Monte Carlo software toolkit Geant4. An approach that reconstructs the production sites of muonic atoms from the & mu;-X ray momentum is proposed. The imaging results indicated a high simulated spatial resolution of 0.1 mm and a significant increase in the detection efficiency compared to that achieved by the 3-mm pinhole imaging technique. In addition, an analysis of the image quality index (Q) revealed that a superior image quality can be achieved for elements with high and medium atomic numbers. The proposed method has the potential to be further developed into an accurate and efficient technique for positioning the distribution of elements.
作者机构：
[Liu, Longcheng; Meng, Shuo] Univ South China, R&D & Modelling Ctr Treatment& Disposal Radioact W, Hengyang 421001, Peoples R China.;[Liu, Longcheng; Meng, Shuo] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Liu, Longcheng] Beijing Res Inst Chem Engn & Met, Beijing 101149, Peoples R China.;[Liu, Longcheng] KTH Royal Inst Technol, Dept Chem Engn, S-10044 Stockholm, Sweden.
关键词：
Variant Time Domain Random Walk algorithms;Boundary conditions;Statistical interpretation;Convolution;Cumulative distribution function
摘要：
In this work, three variant Time Domain Random Walk (TDRW) algorithms were developed for the problem of solute transport in a single fracture-matrix system, where an arbitrary inlet boundary condition can be applied. One approach performs an additional evaluation of integral in terms of injection boundary and the solution to a Dirac delta case. One method makes use of two functions, dependent on specific boundary conditions, to estimate the particle arrival time. The other additionally introduces the concept of solute injection time, resulting from the injection boundary, into the calculation of particle arrival time. To validate the developed variant algorithms, two benchmark cases are considered with respect to a general Dirichlet injection mode and a Robin injection boundary, respectively. The results from three approaches all make a good agreement with those of inverse Laplace transform method. However, the Monte Carlo nature of the TDRW algorithm implies that the accuracy of the computational result is highly dependent on the number of particles applied in the simulation.
期刊：
Journal of Instrumentation,2023年18(4):P04006 ISSN：1748-0221
通讯作者：
Tang, Q;Zhang, YP
作者机构：
[Li, Chi; Tang, Quan; Liu, Yu; Xu, Zhongfang; Guan, Tingyu; Tang, Q] Univ South China, Sch Nucl Sci & Technol, Hengyang, Peoples R China.;[Liu, Jincang; Zhang, Peng; Yang, Changgen; Zhang, YP; Zhang, Yongpeng; Guo, Cong] Chinese Acad Sci, Inst High Energy Phys, Expt Phys Div, Beijing, Peoples R China.;[Liu, Jincang; Zhang, Peng; Yang, Changgen; Zhang, YP; Zhang, Yongpeng; Guo, Cong] Univ Chinese Acad Sci, Sch Phys, Beijing, Peoples R China.;[Liu, Jincang; Zhang, Peng; Yang, Changgen; Zhang, YP; Zhang, Yongpeng; Guo, Cong] State Key Lab Particle Detect & Elect, Beijing, Peoples R China.
通讯机构：
[Zhang, YP ] C;[Tang, Q ] U;Univ South China, Sch Nucl Sci & Technol, Hengyang, Peoples R China.;Chinese Acad Sci, Inst High Energy Phys, Expt Phys Div, Beijing, Peoples R China.;Univ Chinese Acad Sci, Sch Phys, Beijing, Peoples R China.
关键词：
Photon detectors for UV;visible and IR photons (solid-state) (PIN diodes;APDs;Si-PMTs;G-APDs;CCDs;EBCCDs;EMCCDs;CMOS imagers;etc);Very low-energy charged particle detectors
摘要：
Radon and its daughters are one of the most important background sources for low -background liquid scintillator (LS) detectors. The study of the diffusion behavior of radon in the LS contributes to the analysis of the related background caused by radon. Methodologies and devices for measuring radon's diffusion coefficient and solubility in materials are developed and described. The radon diffusion coefficient in the LS was measured for the first time and the solubility coefficient was also obtained. In addition, the radon diffusion coefficient in the polyolefine film which is consistent with data in the literature was measured to verify the reliability of the diffusion device.
期刊：
International Journal of Biological Macromolecules,2023年253(Pt 4):126884 ISSN：0141-8130
通讯作者：
Elwakeel, KZ
作者机构：
[Ahmed, Marwan M.; Akhdhar, Abdullah; Elwakeel, Khalid Z.; Khan, Ziya A.; Sulaiman, Mohamed G. M.; Alghamdi, Huda M.] Univ Jeddah, Coll Sci, Dept Chem, Jeddah, Saudi Arabia.;[Elwakeel, Khalid Z.] Port Said Univ, Fac Sci, Environm Sci Dept, Environm Chem Div, Port Said, Egypt.;[Hamza, Mohammed F.] Univ South China, Sch Nucl Sci & Technol, Heng Yang 421001, Peoples R China.;[Hamza, Mohammed F.] Nucl Mat Author, POB 530, Cairo, Egypt.
关键词：
Flow rate;Gum Arabic-alginate;Heavy metal extraction;Polysaccharides;Well water
摘要：
The change of composition of an adsorbent material has been widely used as a method to increase its adsorption capacity, particularly concerning adsorbents made of polysaccharides. Introducing magnetic adsorbents into contaminated water treatment systems is a highly promising strategy, as it promotes the metal ions removal from water. Considering this, gum Arabic (GA) was associated with alginate (Alg), when magnetite nanoparticles were present or absent, to produce beads that were utilised to take up Cu(II), Cd(II), and Pb(II) from aqueous solution. After a complete characterisation (for which Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, and swelling were used), the adsorption properties were established using batch and column tests. The magnetic beads (MAlg/GA) demonstrated improved adsorption in comparison with the beads made without magnetite (Alg/GA) under the same conditions. In normal adsorption conditions (pH6.0, 25°C, 2.5gL(-1) of adsorbent dosage), the highest uptake capacities recorded for the MAlg/GA beads were: for Cu(II), 1.33mmolg(-1); Cd(II), 1.59mmolg(-1); and for Pb(II), 1.43mmolg(-1). The pseudo-second-order kinetics and Langmuir isotherm models provided good fits for the adsorption of these metals. Overall, ion exchange and physical forces led to the uptake of these metals by both Alg/GA and MAlg/GA; moreover, the functional groups on the beads played crucial roles as binding sites. Additionally, it was observed that flow rates of >2mLmin(-1) did not produce noticeable changes in uptake levels over the same flow period. It was found that the efficient eluting agent was HNO(3) (0.2M). In some cases, the metals were not removed fully from the used beads during the first five cycles of regeneration and reuse. The results of this investigation show that these beads are efficient adsorbents for the removal of metal ions from spiked well water samples.
摘要：
近红外波段(NIR, 波长范围: 780～2 500 nm)在线光谱分析技术具有小型化、 快速检测、 结果稳定可靠等优点, 在工业现场检测领域有着广泛的应用。 由于近红外光谱分析系统受温度影响较大, 传统的光栅分光在线光谱分析系统所采用的光谱仪通常仅对探测器制冷, 光路部分仍然会受到温度影响产生波长漂移等测量误差。 此外, 系统也多采用PC计算机来进行数据采集和控制, 并通过配备独立的工业通讯模块实现光谱分析系统与产线总控系统的通讯, 不仅增加了设备成本与体积, 也显著降低了系统的稳定性。 针对这些问题, 基于STM32单片机开展了在线恒温光谱分析系统研制与测试。 系统采用STM32单片机来控制近红外光谱仪, 通过设定和修改采集间隔时间并采集光谱数据, 对光谱数据进行预处理, 来计算得到目标样品的理化指标。 对于温度控制, 开发了在STM32单片机上运行的基于比例-积分-微分(PID)控制算法的恒温控制系统, 对光谱仪整体(包含光路和电路部分)实现了闭环恒温控制。 同时, 开发了基于STM32单片机的工业通讯接口(包含Modbus协议通讯和4～20 mA电流信号通讯)。 系统实验测试结果表明, 该设计能够长时间稳定运行, 并有效降低了环境温度变化对光谱数据带来的干扰。 在长达48小时的系统运行过程中, 光谱仪温度稳定控制在5 ℃左右, 温控精度优于0.25 ℃。 相对于未恒温控制的运行模式, 恒温控制条件下的平均吸收光谱强度相对标准差显著减小, 并实现了数据采集、 预处理、 样品理化指标计算、 工业信号通讯及温度控制的一体化设计, 以满足工业现场在线检测需求。 Near-Infrared (NIR, wavelength range: 780~2 500 nm) on-line spectral analysis technique has the advantages of miniaturization, rapid detection, and stable and reliable results. Therefore, this technique is widely used in the field of industrial detection. Because the spectroscopic system is significantly affected by ambient temperature, the detector is always cooled in traditional on-line spectroscopic systems. However, measurement errors, such as wavelength drift, are still generated from the optical components when temperature changes. In addition, PCs are always used for system control and spectra acquisition, which significantly increase system instability. In order to solve these problems, this paper proposes an on-line thermostatic control spectroscopic system based on an STM32 single-chip microcomputer. Firstly, STM32 single-chip microcomputer is used to control the near-infrared spectroscopy for spectra data acquisition, configuration setting, preprocessing of the spectral data, and calculation of the physical and chemical parameters of the sample. Secondly, a constant temperature control system has been developed based onthe STM32 single-chip microcomputer, in which the proportional-integral-differential (PID) control algorithm is used. The closed-loop thermostatic control has been realized for the whole spectrometer, including the optical and the circuit part. At last, an industrial communication interface including Modbus protocol communication and 4~20 mA current signal communication has also been developed based on the STM32 single-chip microcomputer. The system test results show that the whole system can be operated stably without PC for a long time. The measure errors originating from the changing of ambient temperature also reduce obviously. During a test of 48-hour system operation, the temperature of the spectrometer is controlled stably at around (5±0.25) ℃. A much smaller relative standard deviation of absorption spectra is obtained when the thermostatic control is applied. The system integrates spectra acquisition, pretreatment, calculation of physical and chemical parameters, industrial communication and thermostatic control, which can satisfy the requirements of industrial on-line detection.
通讯机构：
[Yanfang Xia; Min Liu; Yanfang Xia Yanfang Xia Yanfang Xia; Min Liu Min Liu Min Liu] C;College of Nuclear Science and Technology, University of South China, Hengyang, 421001 China<&wdkj&>Zhuhai Tsinghua University Research Institute Innovation Center, 101 University Ave, Tangjiawan, Zhuhai, 519000 China<&wdkj&>College of Nuclear Science and Technology, University of South China, Hengyang, 421001 China
摘要：
In this article, REFe0.5Cr0.5O3 (RE = La, Y) is prepared by sol–gel method, and the structure is characterized and analyzed by X‐ray diffraction, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, Mössbauer spectroscopy, and magnetism. A reference for future studies of the effect of clusters on Cr‐doped iron‐based calcium is provided. The synthesis of REFe0.5Cr0.5O3 (RE = La, Y) using the sol–gel method is focused and their structural differences are investigated. The results of X‐ray diffraction show that the change of ion radius at position A leads to varying degrees of octahedral distortion and spatial group structure. The scanning electron microscopy analysis reveals micron‐level particles with clear boundaries, while energy‐dispersive X‐ray spectroscopy and room temperature Mössbauer spectra indicate the presence of Fe/Cr clusters in the sample and the transitional valence of iron. Disorder in the B position leads to a saturation moment that is lower than the theoretical value. The thermomagnetic profile shows a reversal of magnetization due to the interaction between the single‐ion magnetic anisotropy and the antisymmetric Dzyaloshinskii–Moriya (DM) interaction, with a broader peak is observed due to cluster formation. The difference in negative magnetic field is due to the difference in net magnetic moment caused by different DM intensities.
摘要：
In response to the lack of plasma bag-breaking equipment and time-consuming manual recovery of plasma in China, this study focuses on the distal end cutting of a plasma bag residual-input tube and designs a machine-vision-based plasma bag residual-input tube cutting system. The system comprises a plasma bag rotation device, a bottom disc, an image acquisition device, a cutting device, and a device control system. The image acquisition device captures images of the rotating plasma bag and calculates the Euclidean distance from the end of the plasma bag input-tube distal end to the outer edge of the bottom support plate and the distance from the input-tube distal end to the centerline of the plasma bag. Two distinct value acquisition algorithms are designed for the two types of input tubes. The screw slide moves accordingly. When the plasma bag is above the cutting part, the cutting part cuts the end of the residual-input tube of the plasma bag. The prototype performance tests reveal that the cutting error is within 10% of the end of the plasma bag input tube distal end, the cutting success rate is 100%, and the processing time for each bag is 2.5 s, which meets the time requirements of the plasma bag breaker.
作者机构：
[Contreras, Miguel Angel Martin] Univ South China, Sch Nucl Sci & Technol, Hengyang, Peoples R China.;[Vega, Alfredo] 28 Changsheng West Rd, Hengyang, Hunan, Peoples R China.;[Vega, Alfredo] Univ Valparaiso, Inst Fis & Astron, A Gran Bretana 1111, Valparaiso, Chile.
通讯机构：
[Contreras, MAM ] U;Univ South China, Sch Nucl Sci & Technol, Hengyang, Peoples R China.
摘要：
In the context of bottom-up AdS/QCD models, we discuss how the configurational entropy can describe heavy non-qq over bar states. Using the nonquadratic softwall model, introduced to describe nonlinear Regge trajectories, we parametrize different multiquark and exotic meson structures to describe Z,, psi, and Zb states as non-qq over bar hadrons in terms of stability. We found that Z, is better described as a hybrid meson with one gluon tube, psi as hadrocharmonium, and Zb as hadronic molecule.
