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Numerical simulation of coupling heat transfer and thermal stress for spent fuel dry storage cask with different power distribution and tilt angles

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Nuclear Science and Techniques 2023年第2期34卷 109-127页

作者： wei‑hao Ji Jian‑Jie Cheng Han‑Zhong Tao wei Li College of Urban Construction Nanjing Tech UniversityNanjing 211800China School of Energy Science and Engineering Nanjing Tech UniversityNanjing 211800China

Dry storage containers must be secured and reliable during long-term storage,and the effect of decay heat released from the internal spent fuel on the cask has become an important research *** this paper,a 3D computational fluid dynamics model is presented,and the accuracy of the calculation is verified,with computational errors of less than 6.2%.The thermal stress of the dry storage cask was estimated by coupling it with a transient temperature *** total power remained constant and adjusting the power ratio of the inner and outer zones had a small effect on the stress results,with a maximum equivalent stress of approximately 5.2 kPa,which occurred at the lower edge of the *** the case of tilt,the temperature gradient varied in a wavy distribution,and the wave crest moved from right to *** the tilt angle affects the air distribution in the annular gap,leading to the shell temperature being transformed,with a maximum equivalent stress of 202 MPa at the bottom of the ***,the equivalent stress in both cases was less than the yield stress(205 MPa).

关键词： Thermal stress CFD simulation Spent nuclear fuel Dry storage cask

基于第一性原理C-Cd掺杂ZnO的电子结构和光学性质的研究

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原子与分子物理学报 2025年第2期42卷 135-142页

作者：张善祥李海侠于镇吴浩伟张巍钟桂林理工大学广西高校先进制造与自动化技术重点实验室桂林541006 桂林理工大学机械与控制工程学院桂林541006

借助于计算材料科学和化学的计算机模拟软件Materials Studio,利用密度泛函理论下的第一性原理的计算方法,系统的计算研究了C、Cd单掺杂以及C和Cd共掺杂(不同浓度)ZnO的形成能、电子结构和光学性质.计算结果表明:单掺杂体系当中,C掺杂... 详细信息

借助于计算材料科学和化学的计算机模拟软件Materials Studio,利用密度泛函理论下的第一性原理的计算方法,系统的计算研究了C、Cd单掺杂以及C和Cd共掺杂(不同浓度)ZnO的形成能、电子结构和光学性质.计算结果表明:单掺杂体系当中,C掺杂时形成能是正的,说明掺杂体系不易形成;共掺杂体系当中,所有掺杂体系的形成能均为负的,C-2Cd掺杂时形成能最低;与本征ZnO相比,所有掺杂体系的禁带宽度均有所降低,由于C元素的掺杂,禁带中产生杂质能级,减小电子跃迁所需要的能量;在光学性质方面,所有掺杂体系在低能区域的吸收图谱、介电函数虚部的峰值与本征ZnO相比均有所增大,且在低能区均发生红移,其中C-2Cd掺杂体系的红移程度最为明显且峰值最大.由此说明C和Cd共掺杂有望提高ZnO的光吸收率和光电转化效率,可以扩展其在光电器件领域中的应用.

关键词： C-Cd共掺杂第一性原理密度泛函理论电子结构光学性质

基于第一性原理的Sc掺杂ZnO对气体的吸附特性研究

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原子与分子物理学报 2025年第1期42卷 54-60页

作者：张巍钟李海侠吴浩伟于镇张善祥桂林理工大学广西高校先进制造与自动化技术重点实验室桂林541006 桂林理工大学机械与控制工程学院桂林541006

CO、SO_(2)、H_(2)S是矿井内由煤炭及围岩中涌出或在生产过程中产生的的典型有毒气体,本文采用第一性原理及密度泛函理论研究了稀土元素Sc掺杂ZnO对单个气体分子(CO、SO_(2)、H_(2)S)的吸附特性.通过对各体系布居分布、能带结构、态密... 详细信息

CO、SO_(2)、H_(2)S是矿井内由煤炭及围岩中涌出或在生产过程中产生的的典型有毒气体,本文采用第一性原理及密度泛函理论研究了稀土元素Sc掺杂ZnO对单个气体分子(CO、SO_(2)、H_(2)S)的吸附特性.通过对各体系布居分布、能带结构、态密度及差分电荷密度分析,研究结果表明:Sc-ZnO(001)-Zn位掺杂体系稳定性最好,Sc-ZnO对单个CO、SO_(2)及H_(2)S分子的吸附能分别为-0.140 eV、-1.885 eV及-0.093 eV,其中对SO2分子的吸附为化学吸附,其余为物理吸附.确定了Sc-ZnO作为半导体气敏传感器来检测三种有毒气体的可行性,尤其是对于SO_(2)气体,为Sc-ZnO作为气敏传感材料实现对矿井有毒气体的检测提供了理论指导.

关键词：第一性原理 Sc掺杂ZnO 有毒气体吸附特性

Single-doped charged gold cluster with highly selective catalytic activity for the reduction of SO2 by CO: First-principles study

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Chinese Physics B 2019年第11期28卷 140-149页

作者： Yan-Ling Hu hao-Ran Zhu Shi-hao wei Department of Microelectronic Science and Engineering School of Physical Science and TechnologyNingbo UniversityNingbo 315211China

It is important for environmental protection to search for catalysts with excellent performance and cost-effective to reduce SO2 by CO. In this work, using first-principles calculation, we have studied the catalytic performance of Au5Mn（M = Ni, Pd, Pt, Cu, Ag, Au; n = 1, 0,-1） clusters, and showed that, by giving a negative charge to the Au5M（M = Cu,Ag, Au, Pd） clusters, we could improve the selectivity of SO2 and avoid effectively catalyst CO poisoning *** the same time, the catalytic reaction rate for the reduction of SO2 by CO with Au5M-（M = Cu, Ag, Au, Pd） clusters is greatly improved when the Au5M clusters are charged. These advantages can be well explained by the charge transfer between the clusters and adsorbed molecules, which means that we can effectively control the performance of the *** equilibrium structures of Au5Mn（M = Ni, Pd, Pt, Cu, Ag, Au; n = 1, 0,-1） clusters without or with adsorbed SO2 or CO molecule are also discussed, and the most stable geometrical structures of Aun5 M-ML（ML = SO2, CO, SO, and COS）can be explained very well by the match of orbitals symmetry and density of electron cloud through their frontier molecular orbitals. Considering the catalyst cost（Cu is much cheaper than Ag and Au）, selectivity of SO2, and effectively avoiding the catalyst CO poisoning, we propose that Au5Cu-is an ideal catalyst for getting rid of SO2 and CO simultaneously.

关键词： bimetallic clusters catalyst first-principles electronic structure

Single boron atom anchored on graphitic carbon nitride nanosheet(B/g-C_(2)N)as a photocatalyst for nitrogen fixation:A first-principles study

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Chinese Physics B 2021年第8期30卷 287-294页

作者： hao-Ran Zhu Jia-Liang Chen Shi-hao wei Department of Microelectronic Science and Engineering School of Physical Science and TechnologyNingbo UniversityNingbo 315211China College of Electronic Information and Optical Engineering Nankai UniversityTianjin 300350China

It is essential to explore high efficient catalysts for nitrogen reduction in ammonia *** on the first-principles calculation,we find that B/g-C_(2)N can serve as high performance photocatalyst in N_(2)fixation,where single boron atom is anchored on the g-C_(2)N to form B/g-C_(2)*** the introduction of B atom to g-C_(2)N,the energy gap reduces from 2.45 eV to 1.21 eV and shows strong absorption in the visible light *** addition,N_(2)can be efficiently reduced on B/g-C_(2)N through the enzymatic mechanism with low onset potential of 0.07 V and rate-determining barrier of 0.50 ***"acceptance-donation"interaction between B/g-C_(2)N and N_(2)plays a key role to active N_(2),and the BN_(2)moiety of B/g-C_(2)N acts as active and transportation *** activity originates from the strong interaction between 1π1π*orbitals of N_(2)and molecular orbitals of B/g-C_(2)N,the ionization of 1πorbital and the filling of 1π*orbital can increase the N≡N bond length greatly,making the activation of N_(2).Overall,this work demonstrates that B/g-C_(2)N is a promising photocatalyst for N_(2)fixation.

关键词： first-principles calculation N_(2)reduction catalysts electronic structure reaction mechanisms reaction paths

Beauty-charm meson family with coupled channel effects and their strong decays

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Chinese Physics C 2024年第12期48卷 11-19页

作者： wei hao Ruilin Zhu School of Physics Nankai UniversityTianjin 300071China Department of Physics and Institute of Theoretical Physics Nanjing Normal UniversityNanjingJiangsu 210023China Peng Huanwu Innovation Research Center Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China

We systematically examined the mass spectra and their two-body hadronic decays of the beauty-charm meson family considering coupled channel *** results can effectively explain the observed Bemeson spectrum,and the prediction of the mass spectrum for unobserved beauty-charm mesons can be tested in future *** with previous studies,we systematically examine the beauty-charm meson family within the coupled channel *** 1S state in beauty-charm meson family has few percent of coupled channel component,while the 2S,1P,and 1D states have more than ten percent of coupled channel *** two-body hadronic decay widths of the 2^(3)P_(2) state is as narrow as 3 *** two-body hadronic decay widths of 3^(1)S_(0),3^(3)S_(1),2^(3)D_(1),2D,2D',and 2^(3)D_(3) are approximately 109,67,60,57,201,and 76 MeV,***,the mixing effects between B_(c)(n^(3)L_(L))and B_(c)(n^(1)L_(L))states are discussed.

关键词： beauty-charm meson coupled channel effects strong decays

Mechanisms for the link between onset and duration of open water in the Kara Sea

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Acta Oceanologica Sinica 2021年第11期40卷 119-128页

作者： Chunming Dong Hongtao Nie Xiaofan Luo hao wei wei Zhao School of Marine Science and Technology Tianjin UniversityTianjin 300072China

The sea ice conditions in the Kara Sea have important impacts on Arctic shipping,oil and gas production,and marine environmental *** this study,sea ice coverage(C_(R))less than 30%is considered as open water,its onset and end dates are defined as T_(open)and T_(close),*** sea ice melt onset(T_(melt))is defined as the date when ice-sea freshwater flux initially changes from ice into the ***-based sea ice concentration(SIC)from 1989 to 2019 shows a negative correlation between T_(open)and T_(close)(r=-0.77,p<0.01)in the Kara *** phenomenon is also obtained through analyzing the hindcast simulation from 1994 to 2015 by a coupled ocean and sea-ice model(NAPA1/4).The model results reveal that thermodynamics dominate the sea ice variations,and ice basal melt is greater than the ice surface *** budget estimation suggests that the heat flux is significant correlated with T_(open)(r=-0.95,p<0.01)during the melt period(the duration of multi-year averaged T_(melt)to T_(open))influenced by the sea ice ***,this heat flux is also suggested to dominate the interannual variation of the heat input during the whole heat absorption process(r=0.81,p<0.01).The more heat input during this process leads to later T_(close)(r=0.77,p<0.01).This is the physical basis of the negative correlation between T_(open)and T_(close).Therefore,the duration of open water can be predicted by T_(open)and thence support earlier planning of marine activities.

关键词： sea ice open water onset duration of open water heat budget Kara Sea

Impact of RF mismatches on the performance of massive MIMO systems with ZF precoding

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Science China(Information Sciences) 2016年第2期59卷 31-44页

作者： hao wei Dongming WANG Jiangzhou WANG Xiaohu YOU National Mobile Communications Research Laboratory Southeast University School of Engineering and Digital Arts University of Kent

Thanks to the channel reciprocity, the time division duplex(TDD) operation is more preferred in massive multiple-input multiple-output(MIMO) systems. Avoiding the heavy feedback of downlink channel state information(CSI) from the user equipment(UE) to the base station(BS), the uplink CSI can be exploited for the downlink precoding. However, due to the mismatches of the radio frequency(RF) circuits at both sides of the link, the whole communication channels are usually not symmetric in practical systems. This paper is focused on the RF mismatches at the UEs and the BS for the multi-user massive MIMO systems with zero forcing(ZF) precoding. The closed-form expressions of the ergodic sum-rates are derived for evaluating the impact of RF mismatches on the system performance. Theoretical analysis and simulation results show that the RF mismatches at the UEs only lead to a negligible performance loss. However, it is imperative to perform reciprocity calibration at the BS, because the RF mismatches at the BS contribute to the inter-user interference(IUI) and result in a severe system performance degradation.

关键词： massive MIMO RF mismatch TDD operation channel reciprocity antenna calibration

Deep-learning-based cryptanalysis of two types of nonlinear optical cryptosystems

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Chinese Physics B 2022年第9期31卷 293-300页

作者： Xiao-Gang Wang hao-Yu wei Department of Applied Physics Zhejiang University of Science and TechnologyHangzhou 310023China Department of Optical Engineering Zhejiang A&F UniversityHangzhou 311300China

The two types of nonlinear optical cryptosystems(NOCs)that are respectively based on amplitude-phase retrieval algorithm(APRA)and phase retrieval algorithm(PRA)have attracted a lot of attention due to their unique mechanism of encryption process and remarkable ability to resist common *** this paper,the securities of the two types of NOCs are evaluated by using a deep-learning(DL)method,where an end-to-end densely connected convolutional network(DenseNet)model for cryptanalysis is *** proposed DL-based method is able to retrieve unknown plaintexts from the given ciphertexts by using the trained DenseNet model without prior knowledge of any public or private *** results of numerical experiments with the DenseNet model clearly demonstrate the validity and good performance of the proposed the DL-based attack on NOCs.

关键词： optical encryption nonlinear optical cryptosystem deep learning phase retrieval algorithm