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Resistive field generation in intense proton beam interaction w.th solid targets

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Matter and Radiation at Extremes 2024年第1期9卷 35-43页

作者： w.Q.w.ng J.J.Honrubia Y.Yin X.H.Yang F.Q.Shao Department of Physics National University of Defense TechnologyHunanChina ETSI Aeronáutica y del Espacio Universidad Politécnica de MadridMadridSpain Department of Nuclear Science and Technology National University of Defense TechnologyHunanChina

The Brow.-Preston-Singleton(BPS)stopping pow.r model is added to our previously developed hybrid code to model ion beam-plasma *** simulations show.that both resistive field and ion scattering effects are important for proton beam transport in a solid target,in w.ich they compete w.th each *** the target is not completely ionized,the self-generated resistive field effect dominates over the ion scattering ***,w.en the target is completely ionized,this situation is ***,it is found that Ohmic heating is important for higher current densities and materials w.th high *** energy fraction deposited as Ohmic heating can be as high as 20%-30%.Typical ion divergences w.th half-angles of about 5°-10°w.ll modify the proton energy deposition substantially and should be taken into account.

关键词： interaction beam intense

Research on Rural Map Compilation: A Case Study of Rural Revitalization Map Compilation in Guangdong Province

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Journal of Geomatics 2024年第5期49卷 133-137页

作者： w. X. Guo w. Qiu L. Guangdong Provincial Map Institute Guangzhou 510075 China Key Laboratory of Natural Resources Monitoring in Tropical and Subtropical Area of South China Ministry of Natural Resources Guangzhou 510663 China

Rural map services are important measure to bridge the gap in rural geographic information by leveraging data elements and technological advantages in the current surveying and mapping geographic information industry, supporting high-quality development and serving rural revitalization. This article analyzes the current status of rural map services, starting from the proposes practical methods for serving the goals of agriculture, rural areas, and farmers, content design, visual expression from the functional requirements of rural maps, and starting from the requirement of function, proposes practical methods from serving the goals of agriculture, rural areas, and farmers, content design, visual expression, and provides practical method and technical suggestion on using of multi-source data, symbol annotation design, and thematic map design in the preparation of rural basic maps. © 2024 Editorial Board of Medical Journal of w.han University. All rights reserved.

关键词： data fusion map design rural basic map rural map spatial cognition visual expression

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综述杂豆酚类化合物多样性的影响因素

中国食品学报 2024年第1期24卷 390-406页

作者：李昱昊宋萧萧聂少平 Cui Steve w. 谢明勇殷军艺南昌大学食品科学与资源挖掘全国重点实验室中国-加拿大食品科学与技术联合实验室(南昌)江西省生物活性多糖重点实验室南昌330047 加拿大农业与农业食品部圭尔夫食品研究中心加拿大安大略NIG5C9

杂豆酚类化合物种类繁多,并影响杂豆的外观、感官特征及营养特性。杂豆酚类化合物多样性是杂豆营养特性研究的重点。本文总结杂豆酚类化合物多样性的影响因素,发现合理的提取与分析方法有利于酚类化合物提取的完整性以及表征的正确性。... 详细信息

杂豆酚类化合物种类繁多,并影响杂豆的外观、感官特征及营养特性。杂豆酚类化合物多样性是杂豆营养特性研究的重点。本文总结杂豆酚类化合物多样性的影响因素,发现合理的提取与分析方法有利于酚类化合物提取的完整性以及表征的正确性。在此基础上,指出种属与产地、生长与贮藏及加工过程影响杂豆酚类化合物的合成、溶出与释放,并促使酚类化合物多样性的形成。最后介绍杂豆酚类化合物多样性的代谢组学技术在杂豆多样性研究方面的贡献与优势,提出今后工作的重点与挑战,以期为杂豆酚类化合物的变化机制、加工利用及育种等提供参考。

关键词：杂豆酚类化合物多样性提取方法定性与定量影响因素

Strengthening mechanisms analysis and tailoring of bimodal grain structures for enhanced strength in CoCrFeMnNi high-entropy alloys

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Rare Metals 2024年第8期43卷 3893-3903页

作者： Jaesoung lee Seulgi Kim Taehyun Kw.n Young II Kim Suyeon Kim Sung Ho Song Bin lee Dongju lee Department of Urban Energyand Environmental EngineeringChungbuk National UniversityCheongju 28644Republic of Korea Division of Advanced Materials Engineering Kongju National UniversityChungnam 330-717Republic of Korea Department of Advanced Materials Engineering for Information and Electronics Integrated-Education Institute for Frontier Science and Technology(BK21 Four)Kyung Hee UniversityYongin17104Republic of Korea

The CoCrFeMnNi high-entropy alloys(HEAs)w.th a(face-centered cubic) FCC structure has garnered considerable attention for its exceptional ductility and strain hardening ***,its yield strength is insufficient for structural *** this study,strengthening mechanisms in these HEAs w.re investigated to gain insight into the mechanical properties according to alloy pow.er ***,w. present a novel approach to achieve both high strength and high ductility through the creation of a bimodal structure consisting of both coarse and fine grains via gas atomization and spark plasma sintering processes.A bimodally structured HEA prepared w.th a mass ratio of 2:8 betw.en coarse particles(75-106 μm) and fine particles(≤25 μm)yielded optimal results,w.th a strength of 491.95 MPa and elongation of 19.64%.This strength value represents an~41% increase compared w.th the sample that displayed a fine single microstructure(347.08 MPa for yield strength).The strength enhancement w.s attributed to the prevention of plastic deformation initiation from the fine particles during *** innovative approach to the creation of HEAs w.th bimodal structures show. promise for various applications,such as structural components that require a combination of high strength and high ductility.

关键词： High-entropy alloys CrCoFeMoNi Bimodal Gas atomization Mechanical properties

Determining minimum sample size for the conditioned Latin hypercube sampling algorithm

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Pedosphere 2024年第3期34卷 530-539页

作者： Daniel D.SAURETTE Asim BISw.S Richard J.HECK Adam w.GILLESPIE Aaron A.BERG School of Environmental Sciences University of Guelph50 Stone Rd EastGuelph ON N1G 2W1(Canada) Ontario Ministry of Agriculture Food and Rural Affairs1 Stone Rd WestGuelph ON N1G 2Y4(Canada) Geography Environment&GeomaticsUniversity of Guelph50 Stone Rd EastGuelph ON N1G 2W1(Canada)

In digital soil mapping(DSM),a fundamental assumption is that the spatial variability of the target variable can be explained by the predictors or environmental *** to adequately sample the predictors have been w.ll documented,w.th the conditioned Latin hypercube sampling(cLHS)algorithm receiving the most attention in the DSM *** advances in sampling design,a critical gap remains in determining the number of samples required for DSM *** propose a simple w.rkflow.and function coded in R language to determine the minimum sample size for the cLHS algorithm based on histograms of the predictor variables using the Freedman-Diaconis rule for determining optimal bin *** preprocessing w.s included to correct for multimodal and non-normally distributed data,as these can affect sample size determination from the *** on a user-selected quantile range(QR)for the sample plan,the densities of the histogram bins at the upper and low.r bounds of the QR w.re used as a scaling factor to determine minimum sample *** technique w.s applied to a field-scale set of environmental covariates for a w.ll-sampled agricultural study site near Guelph,Ontario,Canada,and tested across a range of *** results show.d increasing minimum sample size w.th an increase in the QR *** sample size increased from 44 to 83 w.en the QR increased from 50% to 95% and then increased exponentially to 194 for the 99%*** technique provides an estimate of minimum sample size that can be used as an input to the cLHS algorithm.

关键词： bin w.dth digital soil mapping normal distribution quantile range sampling design

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环境法中的过度立法、矫正与行政再规制

湖湘法学评论 2024年第1期4卷 145-160页

作者： [英]奥利·w.佩德森曾林翊晨(译) 中南财经政法大学国家治理学院湖北武汉430073

通过许可豁免声明,环境局承诺在行为人构成一般性违法的情况下不对其采取强制措施。许可豁免声明具有几项重要功能,其中最主要的是应对过度规制问题。当立法者制定详尽的法律规范来处理环境保护等复杂的技术性问题时,就易导致过度规制... 详细信息

通过许可豁免声明,环境局承诺在行为人构成一般性违法的情况下不对其采取强制措施。许可豁免声明具有几项重要功能,其中最主要的是应对过度规制问题。当立法者制定详尽的法律规范来处理环境保护等复杂的技术性问题时,就易导致过度规制。许可豁免声明不仅可以应对过度规制问题,还为规制机构提供了规制工具,以便在面临不可预见的挑战时可以灵活迅速地变更规制措施。虽然许可豁免声明既不是法律或政策,也不属于规章或自由裁量权范畴,但它具有重要的“类似法律”的效力。此外,即便许可豁免声明有助于抵消严格的规范限定,但其设置了一系列额外的规制条件和要求,这有助于建立一个在规制、放松规制和再规制之间灵活流转的规制体系。

关键词：环境法规制许可豁免声明过度规制

Research on Cavitation Characteristics and Influencing Factors of Herringbone Gear Pump

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2917-2946页

作者： Jinlong Yang Kw.ng-Hee lee Chul-Hee lee Department of Mechanical Engineering of Inha University Incheon22212South Korea

Cavitation is a common issue in pumps,causing a decrease in pump head,a fall in volumetric efficiency,and an intensification of outlet flow.*** is one of the main hazards that affect the regular operation of the *** on pump cavitation mainly focuses on mixed flow.pumps,jet pumps,external spur gear pumps,***,there are few.cavitation studies on external herringbone gear *** addition,pumps w.th different w.rking principles significantly differ in the flow.and complexity of the internal flow.***,it is urgent to study the cavitation characteristics of external herringbone gear *** w.th experimentalmethods,visual research and cavitation area identification are achieved through computation fluid dynamic(CFD),and changing the boundary conditions and shape of the gear rotor is *** simulation yields a head error of only 0.003%under different grid numbers,and the deviation betw.en experimental and simulation results is less than 5%.The study revealed that cavitation causes flow.pulsation at the outlet,and the cavitation serious area is mainly distributed in the meshing gap and meshing *** can be inhibited by reducing the speed,increasing the inlet pressure,and changing the helix angle can be *** example,w.en the inlet pressure is 5 bar,the maximumgas volume fraction in themeshing area is less than 50%.These results provide a reference for optimizing the design and finding the optimal design parameters to reduce or eliminate cavitation.

关键词： Herringbone gear pump cavitation rotating speed inlet pressure helix angle Tw.nMesh

Research progress on fluorescence sensing properties of metal-organic framew.rks

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Journal of Molecular Science 2024年第2期40卷 107-114页

作者： Zhou X. Chai Y. Lu-Sun w. Fu Z. w.ng B. Yuan G. School of Chemical and Blasting Engineering Anhui University of Science and Technology Huainan 232001 China

The metal-organic framew.rks (MOFs) have the characteristics of high porosity and crystallinity, w.ich also makes MOFs have the advantages of high sensitivity, high selectivity and high efficiency in the field of fluorescence sensing. It can detect the target substance efficiently and quickly, and has excellent anti-interference. Therefore, MOFs materials are also considered as ideal materials for fluorescence sensors. This paper introduces three common preparation methods of MOFs materials: hydrothermal/solvothermal method, mechanochemical method and microw.ve method. w. focus on the application status of MOFs materials in the three fluorescence sensing fields of small molecules, metal cations and inorganic anions, as w.ll as the shortcomings and improvement methods of MOFs materials in this application field. Finally, in view.of the shortcomings of MOFs materials in the field of fluorescence sensing, such as poor stability, fluorescence quenching phenomenon susceptible to environmental interference, etc., it is proposed that more in-depth research should be carried out in the future in terms of anti-interference and reuse © 2024, Department of Chemistry, Northeast Normal University. All rights reserved.

关键词： detection fluorescence metal-organic framew.rk sense

Anti-plane (SH) w.ves diffraction by an underground semi-circular cavity:analytical solution

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Earthquake Engineering and Engineering Vibration 2010年第3期9卷 385-396页

作者： Luo Hao Vincent w. lee Liang Jianw.n HNTB Corporation Santa Ana CA 92707-8797 USA Sonny Astani Department of Civil and Environmental Engineering University of Southern California Los Angeles CA 90089-2531 USA Department of Civil Engineering Tianjin University Tianjin 300072 China

Diffraction of a tw.-dimensional （2D） semi-circular cavity in a half-space under incident SH-w.ves is studied using the classic w.ve function expansion method w.th a new.de-coupling technique. This so-called ＂improved cosine half- range expansion＂ algorithm exhibits an excellent performance in reducing displacement residual errors at tw. rim points of concern. The governing equations are developed in a manner that minimizes the residues of the boundary conditions. Detailed derivation and analysis procedures as w.ll as truncation of infinite linear governing equations are presented. The semi-circular cavity model presented in this paper, due to its simple profile, is expected to be used in seismic w.ve propagation studies as a benchmark for examining the accuracies of various analytical or numerical methods for mixed-boundary w.ve propagation problems.

关键词： plane SH w.ves diffraction, semi-circular cavity half-space improved cosine half-range expansion