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Rem-meter correction factor for measuring high energyneutrons outside concrete shielding

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Nuclear Science and Techniques 1998年第2期9卷 109-112页

作者： li gui-sheng (Institute of Modern Physics, the Chinese Academy of Sciences, Lanzhou 730000) Inititute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China

Correction factors of both Rem-meters, the 10 inch diameter single-sphere Remmeter and the standard A-B Rem-meter, were estimated for measuring high energy neutron dose equivalent outside a concrete shielding wall and the effects that the emitted neutron spectra become remarkably "harder" penetrated through a concrete shielding wall, and the energy response of the Rem-meter were taken in account. The estimated results could be applied in the measurement of neutron dose equivalent for the intermediate energy heavy ion reactions to avoid the difficulty induced by the energy response of the Rem-meters.

关键词：高能中子混凝土屏蔽雷姆米修正因子

Influence of Isotope Substitution Helium Atom on Partial Cross Sections in He-HF Collisions

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Communications in Theoretical Physics 2009年第11期52卷 924-928页

作者： YU Chun-Ri ZHANG Jie CHEN li JIANG gui-sheng HUANG Guo-Dong School of Physics ＆ Electric Engineering Anqing Teachers College Anqing 246133 China

Close-coupling equation and anisotropic potential developed in our previous research are applied to HE-SHe （4He, 6He, 8He,10He） collision system, and partial cross sections （PCSs） at the incident energy of 40 me V are calculated. By analyzing the differences of these PCSs, change rules of PCSs with the increase of partial wave number, and with the change of the mass of isotope substitution helium atom are obtained. The results show that excitation PCSs converge faster than elastic PCSs for collision energy and each of systems considered here. Also excitation PCSs converge more rapidly for high-excited states. Tail effect is present only in elastic scattering and low-excited states but not in high- excited states. With the increase of the mass of isotope substitution helium atom, converging speed of elastic, total inelastic, and state-to-state excitation PCS slows down, and the maxima of these PCSs undergoes a regular change.

关键词： isotope substitution partial cross section close-coupling equation He-HF collision

Experimental test of a new neutron threshold detector and its application

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Nuclear Science and Techniques 2002年第3期13卷 149-155页

作者： li gui-sheng, ZHANG Tian-Mei, SU You-Wu, li Shu-Wei(Institute of Modern Physics, the Chinese Academy of Sciences, Lanzhou 730000) Institute of Modern Physics the Chinese Academyo f Sciences Lanzhou 730000 Institute of Modern Physics the Chinese Academyo f Sciences Lznahou 730000

The possibility of using 209Bi as a new threshold detector to measurc high-energy neutrons was investigated for the first time. At the same time the experiment measured successfully the emitted neutron fiuence rate, energy spectrum and dose equivalent rate distributions in the heavy ion target area using a detector complex including 209Bi, 115In, 27A1, 19F and 12C samples.

关键词：阈探测器中子谱实验

Neighbor Sum Distinguishing Total Choosability of Planar Graphs with Maximum Degree at Least 10

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 211-224页

作者： Dong-han Zhang You Lu sheng-gui Zhang li Zhang School of Mathematics and Statistics Northwestern Polytechnical UniversityXi’an710129China School of Mathematics and Computer Application Shangluo UniversityShangluo726000China

A neighbor sum distinguishing(NSD)total coloringφof G is a proper total coloring of G such thatΣz∈EG(u)U{u}φ(z)≠Σz∈EG(v)U{v}φ(z)for each edge uv∈E(G),where EG(u)is the set of edges incident with a vertex *** 2015,Pilśniak and Wozniak conjectured that every graph with maximum degreeΔhas an NSD total(Δ+3)-***,Yang et *** that the conjecture holds for planar graphs withΔ≥10,and Qu et *** that the list version of the conjecture also holds for planar graphs withΔ≥*** this paper,we improve their results and prove that the list version of the conjecture holds for planar graphs withΔ≥10.

关键词： planar graphs neighbor sum distinguishing total choosibility combinatorial nullstellensatz discharging method

A hybrid physics-informed data-driven neural network for CO_(2) storage in depleted shale reservoirs

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Petroleum Science 2024年第1期21卷 286-301页

作者： Yan-Wei Wang Zhen-Xue Dai gui-sheng Wang li Chen Yu-Zhou Xia Yu-Hao Zhou College of Construction Engineering Jilin UniversityChangchun130026JilinChina Institute of Intelligent Simulation and Early Warning for Subsurface Environment Jilin UniversityChangchun130026JilinChina School of Energy Resources China University of GeosciencesBeijing100083China Department of Safety Environmental Protection and Quality ManagementShengli OilfieldSinopecDongying257000ShandongChina Key Laboratory of Thermo-Fluid Science and Engineering of MOE School of Energy and Power EngineeringXi'an Jiaotong UniversityXi'an710049ShaanxiChina College of Computer Science and Technology China University of Petroleum(East China)Qingdao266580ShandongChina Department of Physics University of FribourgFribourg1700Switzerland

To reduce CO_(2) emissions in response to global climate change,shale reservoirs could be ideal candidates for long-term carbon geo-sequestration involving multi-scale transport ***,most current CO_(2) sequestration models do not adequately consider multiple transport ***,the evaluation of CO_(2) storage processes usually involves laborious and time-consuming numerical simulations unsuitable for practical prediction and *** this paper,an integrated model involving gas diffusion,adsorption,dissolution,slip flow,and Darcy flow is proposed to accurately characterize CO_(2) storage in depleted shale reservoirs,supporting the establishment of a training *** this basis,a hybrid physics-informed data-driven neural network(HPDNN)is developed as a deep learning surrogate for prediction and *** incorporating multiple sources of scientific knowledge,the HPDNN can be configured with limited simulation resources,significantly accelerating the forward and inversion ***,the HPDNN can more intelligently predict injection performance,precisely perform reservoir parameter inversion,and reasonably evaluate the CO_(2) storage capacity under complicated *** validation and test results demonstrate that the HPDNN can ensure high accuracy and strong robustness across an extensive applicability range when dealing with field data with multiple noise *** study has tremendous potential to replace traditional modeling tools for predicting and making decisions about CO_(2) storage projects in depleted shale reservoirs.

关键词： Deep learning Physics-informed data-driven neural network Depleted shale reservoirs CO_(2)storage Transport mechanisms

Study on Effectiveness of Solitary-Wave-like Form Based on Overtopping Data from Irregular Wave Tests

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China Ocean Engineering 2024年第4期38卷 701-710页

作者： li Xiao-liang Huang gui-biao School of Naval Architecture&Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

The previous study conducted by li(2022)demonstrates that the Goda graph can be adequately represented by a solitary-wave-like form across the entire range of relative water depth,with the exception of the extremely shallow ***,it remains uncertain whether this form is equally effective when applied to test data generated by irregular waves,as the Goda graph was initially developed based on overtopping data from regular wave ***,it is unclear whether this form is suitable for formulating overtopping discharge at composite vertical *** order to address these questions,a 2D overtopping experiment was conducted,incorporating both simple and composite types of vertical walls,with various relative water depths across the entire range,excluding the extremely shallow zone.A novel analysis procedure was developed,which proved to be highly productive and can be considered a general method for data ***,the study yielded two conclusions:(1)the solitary-wave-like form is remarkably effective in formulating overtopping test data generated by irregular waves,regardless of whether the vertical wall is simple or composite,and(2)the resulting formulas exhibit definitely better performance compared with existing formulas.

关键词： solitary-wave-like form overtopping discharge overtopping formula vertical wall

Securing offshore resources development: A mathematical investigation into gas leakage in long-distance flexible pipes

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Petroleum Science 2024年第4期21卷 2734-2744页

作者： Xiang-An Lu liang-liang Jiang Jian-sheng Zhang Min-gui Wang Guangling College of Yangzhou University Department of Chemical and Petroleum Engineering University of Calgary Department of Energy and Power Engineering Tsinghua University

Gas flexible pipes are critical multi-layered equipment for offshore oil and gas development. Under high pressure conditions, small molecular components of natural gas dissolve into the polymer inner liner of the flexible pipes and further diffuse into the annular space, incurring annular pressure build-up and/or production of acidic environment, which poses serious challenges to the structure and integrity of the flexible pipes. Gas permeation in pipes is a complex phenomenon governed by various factors such as internal pressure and temperature, annular structure, external temperature. In a long-distance gas flexible pipe, moreover, gas permeation exhibits non-uniform features, and the gas permeated into the annular space flows along the metal gap. To assess the complex gas transport behavior in long-distance gas flexible pipes, a mathematical model is established in this paper considering the multiphase flow phenomena inside the flexible pipes, the diffusion of gas in the inner liner, and the gas seepage in the annular space under varying permeable properties of the annulus. In addition, the effect of a variable temperature is accounted. A numerical calculation method is accordingly constructed to solve the coupling mathematical equations. The annular permeability was shown to significantly influence the distribution of annular pressure. As permeability increases, the annular pressure tends to become more uniform, and the annular pressure at the wellhead rises more rapidly. After annular pressure relief followed by shut-in, the pressure increase follows a convex function. By simulating the pressure recovery pattern after pressure relief and comparing it with test results, we deduce that the annular permeability lies between 123 and 512 m D. The results help shed light upon assessing the annular pressure in long distance gas flexible pipes and thus ensure the security of gas transport in the emerging development of offshore resources.

关键词： Offshore resources development Transport security Long-distance flexible pipes Gas leakage Heat and mass transfer model Finite difference calculation

Generation of input spectrum for electrolysis stack degradation test applied to wind power PEM hydrogen production

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Global Energy Interconnection 2024年第4期7卷 462-474页

作者： Yanhui Xu Guanlin li Yuyuan gui Zhengmao li School of Electrical and Electronic Engineering North China Electric Power UniversityBeijing 102206P.R.China School of Electrical Engineering Aalto UniversityFinland

Hydrogen production by proton exchange membrane electrolysis has good fluctuation adaptability,making it suitable for hydrogen production by electrolysis in fluctuating power sources such as wind ***,current research on the durability of proton exchange membrane electrolyzers is *** the typical operating conditions of wind power electrolysis for hydrogen production can provide boundary conditions for performance and degradation tests of electrolysis *** this study,the operating condition spectrum of an electrolysis stack degradation test cycle was *** on the rate of change of the wind farm output power and the time-averaged peak-valley difference,a fluctuation output power sample set was *** characteristic quantities that played an important role in the degradation of the electrolysis stack were *** reduction of the operating data was performed using principal component *** analysis of the data segments was completed using an improved Gaussian mixture clustering *** the annual output power data of wind farms in Northwest China with a sampling rate of 1 min as an example,the cyclic operating condition spectrum of the proton-exchange membrane electrolysis stack degradation test was *** preliminary simulation analysis,the typical operating condition proposed in this paper effectively reflects the impact of the original curve on the performance degradation of the electrolysis *** study provides a method for evaluating the degradation characteristics and system efficiency of an electrolysis stack due to fluctuations in renewable energy.

关键词： Hydrogen production by electrolysis of water Wind power Proton exchange membrane electrolyzer Gaussian mixture model Cyclic operating condition

Centered Waves for the Two-dimensional Pseudo-Steady van der Waals Gas Satisfied Maxwell's Law Around a Sharp Corner

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Chinese Annals of Mathematics,Series B 2024年第04期45卷 537-554页

作者： Shuangrong li Wancheng sheng Department of Mathematics Shanghai University Shanghai 200444 China Department of Mathematics Zhejiang University of Science and Technology Department of Mathematics Newtouch Center for Mathematics of Shanghai University Shanghai University

In this paper, the authors study the centered waves for the two-dimensional(2D for short) pseudo-steady supersonic flow with van der Waals gas satisfied Maxwell's law around a sharp corner. In view of the initial value of the specific volume and the properties of van der Waals gas, the centered waves at the sharp corner are constructed by classification. It is shown that the supersonic incoming flow turns the sharp corner by a centered simple wave or a centered simple wave with right-contact discontinuity or a composite wave(jump-fan, fan-jump or fan-jump-fan), or a combination of waves and constant state. Moreover, the critical angle of the sharp corner corresponding to the appearance of the vacuum phenomenon is obtained.

关键词： Centered simple wave Composite wave Two-dimensional Euler equations Van der Waals gas