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高铁内外部效益平衡理论

北京交通大学学报（社会科学版） 2024年第1期23卷 73-83页

作者：林晓言李红昌北京交通大学经济管理学院北京100044

本文构建高铁内外部效益平衡理论,阐释高铁内外部效益平衡的必然性、必要性及其实现路径。研究认为:高铁内外部效益平衡是高铁可持续发展的重要内涵,应重视密度经济的关键指针作用;高铁内外部效益的不平衡与高铁经济行为主体目标的多元... 详细信息

本文构建高铁内外部效益平衡理论,阐释高铁内外部效益平衡的必然性、必要性及其实现路径。研究认为:高铁内外部效益平衡是高铁可持续发展的重要内涵,应重视密度经济的关键指针作用;高铁内外部效益的不平衡与高铁经济行为主体目标的多元性和不相容相关;高铁内外部效益平衡可通过高铁运输需求增加、铁路产业打破经济垄断和行政垄断引入竞争、构建有责政府广义补贴机制进行动态调整。高铁内外部效益平衡理论对于降低基础设施投资风险,支持经济高质量发展意义明显。

关键词：高铁可持续发展内外部效益平衡高铁企业高铁产品广义补贴有责政府

Effects of concurrent grain boundary and surface segregation on the final stage of sintering: the case of Lanthanum doped yttriastabilized zirconia

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journal of Materials Science & Technology 2017年第3期33卷 251-260页

作者： M.M.Gong S.Dey L.j.Wu C.H.chang H.Li R.H.R.Castro f.Liu State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi＇an 710072 China Department of Materials Science ＆ Engineering University of California Davis CA 95616 USA

Dopants play a critical role in tailoring the microstructure during sintering of compacts. These dopants may form solid solution within the bulk, and/or segregate to the grain boundaries（GBs） and the solidvapor interfaces（free surfaces）, each causing a distinct energetic scenario governing mass transports during densification and grain growth. In this work, the forces controlling the dopant distribution, in particular the possibility of concurrent segregation at both surfaces and GBs, are discussed based on the respective enthalpy of segregation. An equation is derived based on the minimum Gibbs energy of the system to determine enthalpy of segregation from experimental interface energy data, and the results applied to depict the role of La as a dopant on the interface energetics of yttria stabilized zirconia during its final stage of sintering. It is shown that La substantially decreases both GB and surface energies（differently）as sintering progresses, dynamically affecting its driving forces, and consequent grain growth and densification in this stage.

关键词： Grain boundary(GB) segregation Surface segregation Enthalpy of segregation GB energy Surface energy

氟化六方氮化硼的制备及其作为水基添加剂的摩擦学性能

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材料研究学报 2024年第6期38卷 410-422页

作者：王伟常文娟吕凡凡解泽磊于呈呈西安建筑科技大学冶金工程学院西安710055 季华实验室佛山528200

对NH4f氟源进行恒温磁力搅拌和球磨辅助氟化,制备出氟化氮化硼纳米片(f-BNNSs),在接触Ti6-Al-4V(TC4)/GCr15的条件下研究了六方氮化硼纳米片(h-BNNSs)和氟化氮化硼纳米片(f-BNNSs)作为水基润滑添加剂的摩擦学行为。结果表明,随着h-BN与N... 详细信息

对NH4f氟源进行恒温磁力搅拌和球磨辅助氟化,制备出氟化氮化硼纳米片(f-BNNSs),在接触Ti6-Al-4V(TC4)/GCr15的条件下研究了六方氮化硼纳米片(h-BNNSs)和氟化氮化硼纳米片(f-BNNSs)作为水基润滑添加剂的摩擦学行为。结果表明,随着h-BN与NH4f的质量比从1∶2提高到1∶4这种水基润滑添加剂的平均摩擦系数先由0.3135降低到0.1435然后提高到0.2177。h-BN与NH4f的质量比为1∶3时的f-BNNSs12其摩擦系数和磨损率比h-BNNSs分别降低了55%和75%。基于磨损痕迹的分析结果表明,f-BNNSs12良好的减磨耐磨性能可归因于:1、纳米片层间相互作用的减弱使相对滑动变得容易;2、f-BNNSs12的不相称纳米棒-纳米片结构形成滚动摩擦使其润滑性能良好;3、f-BNNSs12沉积在摩擦副表面生成不连续的润滑膜,避免了与摩擦副的直接接触。

关键词：无机非金属材料六方氮化硼氟化氮化硼纳米片水基润滑添加剂摩擦学性能

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三乙醇胺络合作用下钢渣的水化特性

硅酸盐学报 2024年第5期52卷 1621-1630页

作者：常磊黄炳银王剑锋刘辉王亚丽崔素萍北京工业大学材料科学与工程学院北京100124 北京工业大学碳中和未来技术学院北京100124

三乙醇胺(TEA)作为外加剂常用于提高钢渣胶凝活性,但目前关于TEA对钢渣水化的研究仍集中在钢渣-水泥复合体系,难以明确TEA对钢渣水化特性的影响。本工作将TEA引入纯钢渣体系,通过抗压强度、水化热、热重、物相分析、络合能力测定和溶解... 详细信息

三乙醇胺(TEA)作为外加剂常用于提高钢渣胶凝活性,但目前关于TEA对钢渣水化的研究仍集中在钢渣-水泥复合体系,难以明确TEA对钢渣水化特性的影响。本工作将TEA引入纯钢渣体系,通过抗压强度、水化热、热重、物相分析、络合能力测定和溶解特性分析来表征TEA络合作用下纯钢渣的水化特性。结果表明:TEA显著提高了硬化钢渣浆体早期及后期抗压强度,主要原因是TEA促进了钢渣中铝相(C3A、C12A7)和铁相(C2f)的水化及其与CaCO3之间的反应,生成了对抗压强度有利的单碳型水化碳铝酸盐[C4(A,f)■H11],从而提高了钢渣浆体的水化程度。TEA对水化的促进与TEA的络合作用有关,TEA可以与Ca^(2+)、Al^(3+)、fe^(3+)3种金属离子络合,在一定范围内(TEA与金属离子摩尔比小于等于1时),TEA与金属离子间的络合能力从强到弱依次为fe^(3+)、Al^(3+)、Ca^(2+)。TEA通过络合作用促进了钢渣的溶解,从而促进了钢渣的水化。

关键词：钢渣三乙醇胺络合水化

Revealing pion and kaon structure via generalised parton distributions

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Chinese Physics C 2022年第1期46卷 80-101页

作者： K.Raya Z-f.Cui L.chang j.M.Morgado C.D.Roberts j.Rodríguez-Quintero School of Physics Nankai UniversityTianjin 300071China Departamento de física Teórica y del Cosmos Universidad de GranadaE-18071GranadaSpain Instituto de Ciencias Nucleares Universidad Nacional Autónoma de MéxicoApartado Postal 70-543CDMX 04510México School of Physics Nanjing UniversityNanjingJiangsu 210093China Institute for Nonperturbative Physics Nanjing UniversityNanjingJiangsu 210093China Department of Integrated Sciences and Center for Advanced Studies in Physics Mathematics and ComputationUniversity of HuelvaE-21071 HuelvaSpain

Clear windows onto emergent hadron mass(EHM)and modulations thereof by Higgs boson interactions are provided by observable measures of pion and kaon structure,many of which are accessible via generalised parton distributions(GPDs).Beginning with algebraic GPD Ansätze,constrained entirely by hadron-scaleπand K valence-parton distribution functions(Dfs),in whose forms both EHM and Higgs boson influences are manifest,numerous illustrations are *** include the properties of electromagnetic form factors,impact parameter space GPDs,gravitational form factors and associated pressure profiles,and the character and consequences of allorders *** analyses predict that mass-squared gravitational form factors are stiffer than electromagnetic form factors;reveal that K pressure profiles are tighter than profiles,with both mesons sustaining near-core pressures at magnitudes similar to that expected at the core of neutron stars;deliver parameter-free predictions for and K valence,glue,and sea GPDs at the resolving scale l=2GeV;and predict that at this scale the fraction of meson mass-squared carried by glue and sea combined matches that lodged with the valence degrees-of-freedom,with a similar statement holding for mass-squared radii.

关键词： continuum Schwinger function methods emergence of hadron mass Nambu-Goldstone modes-pions and kaons nonperturbative quantum field theory parton distributions strong interactions

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磁谐振索力测试的温度敏感性及补偿方法

中国公路学报 2024年第5期37卷 278-288页

作者：张洪尹昌华廖棱张森华周建庭重庆交通大学山区桥梁及隧道工程国家重点实验室重庆400074 重庆交通大学土木工程学院重庆400074 重庆交通大学材料科学与工程学院重庆400074

磁谐振测索力方法是一种高灵敏度的索力检测新方法,为了减小磁谐振测索力方法的温度误差,基于磁弹效应和磁谐振现象,分析了感应电压与拉索索力和温度之间的相关性,制作了双线圈磁谐振传感器,搭建了水浴环境下的荷载-温度耦合试验系统,... 详细信息

磁谐振测索力方法是一种高灵敏度的索力检测新方法,为了减小磁谐振测索力方法的温度误差,基于磁弹效应和磁谐振现象,分析了感应电压与拉索索力和温度之间的相关性,制作了双线圈磁谐振传感器,搭建了水浴环境下的荷载-温度耦合试验系统,开展了空气和水浴环境下的对比试验以及水浴环境下的恒温变载试验和恒载变温试验。结果表明:水浴和空气环境下,传感器次级线圈感应电压增量随钢绞线拉力有相同的变化趋势,相同工况下各试件的滞回曲线灵敏度kV/f和滞回度D差异很小,最大差异百分比分别为7.1%和3.8%,这表明磁谐振测索力方法测试结果具有可靠的稳定性和可重复性;水浴环境相对空气环境差异较小,恒温变载曲线的灵敏度kV/f平均降低了7.5%,滞回度D平均提高了6.1%,表明在水浴环境下开展试验是可行和有效的;低温下感应电压随拉力的变化曲线具有较高的灵敏度和较低的滞回度,灵敏度随温度自25℃升高至80℃下降了47.8%;0℃~60℃范围,各工况升温过程与降温过程中感应电压与温度之间近似呈线性正相关,线性拟合优度大于0.96,利用0℃~60℃段降温-升温拟合曲线对温度拟合曲线对各变载工况下的试件进行温度补偿,最大误差集中在3%以内,表明可根据温度补偿曲线对磁谐振测索力方法进行温度补偿。

关键词：桥梁工程索力测试荷载-温度耦合试验磁谐振温度补偿

Optimization of performance of the KM2A full array using the Crab Nebula

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Chinese Physics C 2024年第6期48卷 169-178页

作者：曹臻 f.Aharonian 安琪阿西克古白云翔包逸炜 D.Bastieri 毕效军毕玉江蔡金庭曹晴曹文羽曹喆常进常劲帆陈尚明陈恩生陈亮陈林陈龙陈明君陈玛丽陈起辉陈素弘陈天禄陈阳程宁程耀东崔明阳崔树旺崔晓红崔昱东戴本忠代洪亮戴子高单增罗布 D.della Volpe 董绪强段凯凯樊军辉范一中方军方堃冯存峰封莉冯少辉丰晓婷冯有亮 S.Gabici 高博高川东高林青高启高卫高伟康葛茂茂耿利斯 G.Giacinti 龚光华苟全补顾旻皓郭福来郭晓磊郭义庆郭莹莹韩毅昂何会海贺昊宁何佳银何新波何钰 M.Heller 贺远强侯博文侯超侯贤胡红波胡铨胡世聪黄代绘黄天奇黄文俊黄性涛黄晓渊黄勇黄志成季筱璐贾焕玉贾康江琨姜晓巍姜泽军金敏康明铭柯通 D.Kuleshov.K.Kurinov 李兵兵李澄李骢李丹李飞李海波李会财李华阳李军李剑李捷李凯李文龙李文莲李秀荣李昕李一卓李哲黎卓梁恩维梁云峰林苏杰刘冰刘成刘栋刘虎刘海东刘佳刘江来刘金艳刘茂元柳若愚刘四明刘伟刘怡刘以农鲁睿罗晴吕洪魁马伯强马玲玲马欣华毛基荣闵振 W.Mitthumsiri 穆慧君南云程 A.Neronov 区子维庞彬宇 P.Pattarakijwanich 裴致远齐孟尧祁业情乔冰强秦家军 D.Ruffolo A.Sáiz D.Semikoz 邵澄宇邵琅 O.Shchegolev 盛祥东舒富文宋慧超 Yu.V.Stenkin V.Stepanov 苏扬孙秦宁孙晓娜孙志斌谭柏轩唐庆文唐泽波田文武王超王昌贝王广威王洪光王惠惠王建成汪凯王利苹王玲玉王培汉王冉王为王祥高王祥玉王阳王玉东王岩谨王忠海王仲翔王振王铮韦大明魏俊杰魏永健文韬吴超勇吴含荣武莎吴雪峰吴雨生席邵强夏捷夏君集项光漫肖迪泫肖刚辛广广辛玉良邢祎熊峥徐东莲徐仁峰徐仁新徐伟立薛良闫大海颜景志颜田杨朝文杨帆杨冯帆杨何文杨佳盈杨莉莉杨明洁杨睿智杨深邦姚玉华姚志国叶一锰尹丽巧尹娜游晓浩游智勇于艳红袁强岳华曾厚敦曾婷轩曾玮查敏张彬彬张丰张海明张恒英张建立张丽霞张力张鹏飞张佩佩张瑞张少博张少如张寿山张潇张笑鹏张云峰张毅张勇赵兵赵静赵雷赵立志赵世平郑福周斌周浩周佳能周猛周平周荣周勋秀祝成光祝凤荣朱辉朱科军左雄 LHAASO Collaboration Key Laboratory of Particle Astrophyics&Experimental Physics Division&Computing Center Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Tianfu Cosmic Ray Research Center Chengdu 610000China Dublin Institute for Advanced Studies 31 Fitzwilliam Place2 DublinIreland Max-Planck-Institut for Nuclear Physics P.O.Box 10398069029 HeidelbergGermany State Key Laboratory of Particle Detection and Electronics China University of Science and Technology of China Hefei 230026China School of Physical Science and Technology&School of Information Science and Technology Southwest Jiaotong UniversityChengdu 610031China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Hebei Normal University Shijiazhuang 050024China Key Laboratory of Dark Matter and Space Astronomy&Key Laboratory of Radio Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China Tsung-Dao Lee Institute&School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000TibetChina National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Physics and Astronomy(Zhuhai)&School of Physics(Guangzhou)&Sino-french Institute of Nuclear Engineering and Technology(Zhuhai) Sun Yat-sen UniversityZhuhai 519000&Guangzhou 510275China School of Physics and Astronomy Yunnan UniversityKunming 650091China Département de Physique Nucléaire et Corpusculaire Facultéde SciencesUniversitéde Genève24 Quai Ernest Ansermet1211 GenevaSwitzerland Institute of frontier and Interdisciplinary Science Shandong UniversityQingdao 266237China APC Universit'e Paris Cit'eCNRS/IN2P3CEA/IRFUObservat

The full array of the Large High Altitude Air Shower Observatory(LHAASO)has been in operation since july *** its kilometer-square array(KM2A),we optimized the selection criteria for very high and ultrahigh energyγ-rays using data collected from August 2021 to August 2022,resulting in an improvement in significance of the detection in the Crab Nebula of approximately 15%,compared with that of previous *** the implementation of these new selection criteria,the angular resolution was also significantly improved by approximately 10%at tens of *** aspects of the full KM2A array performance,such as the pointing error,were also calibrated using the Crab *** resulting energy spectrum of the Crab Nebula in the energy range of 10-1000 TeV are well fitted by a log-parabola model,which is consistent with the previous results from LHAASO and other experiments.

关键词： γ-ray Crab Nebula significance

A proposal on complementary determination of the effective electro-weak mixing angles via doubly heavy-flavored hadron production at a super Z-factory

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Science China(Physics,Mechanics & Astronomy) 2020年第8期63卷 61-70页

作者： Xu-chang Zheng Chao-Hsi chang Tai-fu feng Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Physics Chongqing UniversityChongqing 401331China China Center of Advanced Science and Technology(CCAST)(World Laboratory) Beijing 100190China Department of Physics Hebei UniversityBaoding 071002China

To test the standard model(SM)precisely and to look for the clues deviating from SM,a proposal for determining the effective electro-weak mixing angles sin2θefff(particularly f=lept,c,b)is *** is via observing the asymmetries(the forward-backward one AfB,the left-right one ALR and the combined left-right forward-backward one ALRfB)of the doubly heavy-flavored hadrons in the production at a super Z-factory(an e+e-collider designed with a luminosity as high as possible for modernday techniques runs around the center-of-mass energy s1/2=mZ).To see the sensitivity,uncertainties as well as the event accumulation precisely,the observables for describing the asymmetries of the produced hadrons are computed numerically with varying effective mixing angles,and based on the result analyses,it is concluded that the proposal may offer an independent complement determination of the effective mixing angles.

关键词： electro-weak mixing angle production of doubly heavy-flavored hadron asymmetries super Z-factory

基于产量品质及水肥利用率的核桃水肥耦合方案优化

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干旱地区农业研究 2024年第3期42卷 162-172页

作者：常子康梁国成彭艳平赵经华新疆农业大学水利与土木工程学院新疆乌鲁木齐830052 乌鲁木齐经济技术开发区(头屯河区)建设局新疆乌鲁木齐830026 中国能源建设集团新疆电力设计院有限公司新疆乌鲁木齐830002 新疆水利工程安全与水灾害防治重点实验室新疆乌鲁木齐830052

针对干旱区核桃水肥利用效率低及高效水肥制度不明晰的问题,以新疆阿克苏地区核桃树为研究对象,以核桃提质增效为目标,研究水肥耦合条件下对滴灌核桃的生理生长指标、果实品质、产量的影响。为了更精准地预测水肥制度,以灌水量(225 m^(3... 详细信息

针对干旱区核桃水肥利用效率低及高效水肥制度不明晰的问题,以新疆阿克苏地区核桃树为研究对象,以核桃提质增效为目标,研究水肥耦合条件下对滴灌核桃的生理生长指标、果实品质、产量的影响。为了更精准地预测水肥制度,以灌水量(225 m^(3)·hm^(-2),W1;300 m^(3)·hm^(-2),W2;375 m^(3)·hm^(-2),W3)、施肥量(常规施肥量0.5倍(236.93 kg·hm^(-2)),f1;常规施肥量(473.85 kg·hm^(-2)),f2;常规施肥量2倍(947.7 kg·hm^(-2)),f3)为试验因素,通过建立关于核桃的果实品质、产量、水分利用效率和肥料偏生产率的二元二次回归模型,并采用二代非支配排序遗传算法(NSGA-Ⅱ)对该回归模型进行验证求解,从而模拟出最优水肥制度。结果表明:灌水量和施肥量两因子及其耦合效应对核桃的生长指标均有显著影响,核桃的果实品质、产量和水肥利用率随着灌水量和施肥量的增加呈现先增加后减小的趋势,在各处理情况下,W2f2处理为最优的灌溉施肥处理。通过NSGA-Ⅱ模拟出的最优水肥制度为灌水量和施肥量分别是336.93 m^(3)·hm^(-2)和715.21 kg·hm^(-2)。最终对应的蛋白质含量、产量、水分利用效率和肥料偏生产率分别是21.36%、2971.66 kg·hm^(-2)、8.76 kg·mm^(-1)·hm^(-2)和1.02。

关键词：核桃滴灌水肥耦合水分利用效率肥料偏生产率 NSGA-Ⅱ算法