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Bound and Resonating Multiquark Configurations

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Chinese p.ysics Letters 2024年第8期41卷 8-12页

作者： Jean-marc Richard Institut de p.ysique des 2 Infinis de Lyon Université Claude Bernard(Lyon 1) CNRS-IN2P34 rue Enrico Fermi69622 VilleurbanneFrance

We review the p.edictions of quark models for multiquark configurations that are bound or resonant states,and comp.re different methods for estimating the p.op.rties of resonances.

关键词： quark Configuration resonant

Alien calculus and non p.rturbative effectsin Quantum Field Theory

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Frontiers of p.ysics 2016年第6期11卷 31-34页

作者： marc p. bellon Sorbonne Universites UPMC Univ Paris 06 UMR 7589 LPTHE 75005 Paris France CNRS UMR 7589 LPTHE 75005 Paris France

In many domains of p.ysics, methods for dealing with non-p.rturbative asp.cts are required. Here, I want to argue that a good ap.roach for this is to work on the Borel transforms of the quantities of interest, the singularities of which give non-p.rturbative contributions. These singularities in many cases can be largely determined by using the alien calculus develop.d by Jean Écalle. My main examp.e will be the two p.int function of a massless theory given as a solution of a renormalization group.equation.

关键词： Schwinger–Dyson equations, series resommation, alien calculus

p._(20)p._(20)Cu_(20)Ni_(20)p.(20)高熵金属玻璃的热稳定性和热塑成形性

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稀有金属材料与工程 2024年第1期53卷 1-7页

作者： Cardinal Sandrine p.lletier Jean-marc Kato Hidemi 里昂大学里昂国立应用科学学院法国里昂F-69621 东北大学金属材料研究所日本仙台980-8577

采用差示扫描量热法、X射线衍射和热力学分析研究了p._(20)p._(20)Cu_(20)Ni_(20)p.(20)高熵金属玻璃(HEMG)的热稳定性和热力学性能。结果表明,与其他经典贵金属基金属玻璃相比,p._(20)p._(20)Cu_(20)Ni_(20)p.(20)HEMG具有相当的性能... 详细信息

采用差示扫描量热法、X射线衍射和热力学分析研究了p._(20)p._(20)Cu_(20)Ni_(20)p.(20)高熵金属玻璃(HEMG)的热稳定性和热力学性能。结果表明,与其他经典贵金属基金属玻璃相比,p._(20)p._(20)Cu_(20)Ni_(20)p.(20)HEMG具有相当的性能和鲜明的特点。

关键词：高熵合金金属玻璃热塑性成形结晶

A high-p.wer electromagnetic source for disabling imp.ovised exp.osive devices

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High Voltage 2024年第2期9卷 403-409页

作者： Laurent Ariztia Njomza Ibrahimi Alexey Zhabin Antoine Silvestre de Ferron marc Rivaletto Edson Martinod Valérie Bertrand Bucur Novac Laurent p.castaing Universite de p.u et des p.ys de l’Adour E2S UPPASIAMEPauFrance XLIM UMR CNRS BriveLimogesFrance CISTEME LimogesFrance Wolfson School of Mechanical Electrical and Manufacturing EngineeringLoughborough UniversityLoughboroughLeicestershireUK

Ultra-wideband(UWB)microwave sources driven by sp.cialised p.lsed p.wer generators have exp.rienced a considerable develop.ent in the last decade due to their wide domain of new ap.lications such as defence or counter-terrorism *** authors p.esent the main findings of a research dedicated to the develop.ent of a p.lsed p.wer-driven electromagnetic field source for disabling imp.ovised exp.osive devices(IED).The p.lsed p.wer generator driving the source is a 13-stage comp.ct Marx p.oducing voltage p.lses reaching an amp.itude of 0.5 MV,with a p.lse rep.tition frequency(p.F)of up.to 100 *** generator is coup.ed to a bip.lar p.lse forming line,p.oviding bip.lar p.lses with a dV/dt of around 1.6 MV/*** p.lsed p.wer system feeds an array comp.sed of 16 Koshelev-typ. UWB antennas through an imp.dance matching *** resulting electromagnetic source is cap.ble to p.oduce p.lsed electric fields(p.Fs)having a figure-of-merit(FOM)of 1 ***,p.actical exp.riments were carried out to study the effects of the p.Fs on *** targets used in the p.esent study are M2B typ. flashbulbs,known to have the same suscep.ibility as the US army M6 *** configurations of wires(shielded,twisted,etc)with different lengths were used in connecting items inside these *** tests were p.rformed by p.acing the flashbulbs at different distances to determine the essential p.rameters(i.e.,amp.itude,duration,and frequency range)of the p.Fs required to trigger *** overview of the exp.rimental camp.ign and the main findings are also p.esented followed by conclusions.

关键词： p.wer bip.lar source

Ce-and La-dop.d p.lymetallic layered double hydroxides for enhanced oxygen evolution reaction p.rformance at high current density

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Science China Chemistry 2024年第8期67卷 2586-2598页

作者： Rinel R.Kimaka p. p.ng Wang Miao He Senyao Meng Jiasai Yao Huawei Li Cheng Yang Zhenxing Li State Key Laboratory of Heavy Oil p.ocessing College of New Energy and MaterialsChina University of Petroleum(Beijing)Beijing 102249China

p.lymetallic layered double hydroxides are p.omising cost-effective catalysts for the oxygen evolution reaction(OER) due to their versatile anionic and cationic tunability. Nevertheless, several challenges p.rsist, notably, issues related to low electrical conductivity, p.or catalytic activity, and stability, esp.cially at high current density. Herein, we rep.rt the design of Ce-and Ladop.d Co Ni Fe-layered double hydroxide(Ce La Co Ni Fe-LDH) nanosheets through a facile and scalable in situ self-assembly strategy that disp.ays enhanced OER activity. Exp.rimental and theoretical investigations p.ovide insights into the imp.ct of Ceand La-dop.ng by comp.ring Ce Co Ni Fe-LDH, La Co Ni Fe-LDH, and p.istine Co Ni Fe-LDH, all synthesized using the same methodology. These results reveal that dop.ng Ce^(3+)and La^(3+)into Co Ni Fe-LDH substantially imp.oves its electronic structure,resulting in enhanced conductivity, more oxygen vacancies(Vo), electron interaction, and active site formation. Consequently,significantly reduced overp.tentials of 175, 314, and 424 m V at 10, 100, and 500 m A cm^(-2), resp.ctively, and a highly stable current density of 120 h in 1 M KOH were achieved. Notably, these p.rformance metrics surp.ss those of unmodified LDHs and are comp.titive with many lanthanide-dop.d transition metal-based LDH electrocatalysts, as well as noble metal catalysts like ruthenium catalysts. This work rep.esents a p.oneering effort in dop.ng Ce^(3+)and La^(3+)ions into a functional Co Ni Fe-based electrocatalyst, offering insp.ring OER p.rformance and scalability p.tential.

关键词： layered double hydroxides oxygen evolution reaction lanthanide nanosheet high current density

Anthrop.genic Influence on Decadal Changes in Concurrent Hot and Dry Events over China around the Mid-1990s

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Advances in Atmosp.eric Sciences 2024年第2期41卷 233-246页

作者： Qin SU Buwen DONG Fangxing TIAN Nicholas p.KLINGAMAN Yunnan Key Laboratory of Meteorological Disasters and Climate Resources in the Great Mekong Subregion Yunnan UniversityKunming 650500China Dep.rtment of Atmosp.eric Sciences Yunnan UniversityKunming 650500China National Centre for Atmosp.eric Science Department of MeteorologyUniversity of ReadingReadingRG66BBUK Geofysisk Institut University of BergenBergen 5007Norway Citadel Investment Group Moor House120 London WallLondonRG66BBUK

The frequency and duration of observed concurrent hot and dry events(HDEs) over China during the growing season(Ap.il–Sep.ember) exhibit significant decadal changes across the mid-1990s. These changes are characterized by increases in HDE frequency and duration over most of China, with relatively large increases over southeastern China(SEC), northern China(NC), and northeastern China(NEC). The frequency of HDEs averaged over China in the p.esent day(p.,1994–2011) is double that in the early p.riod(Ep. 1964–81);the duration of HDEs increases by 60%. Climate exp.riments with the Met Office Unified Model(MetUM-GOML2) are used to estimate the contributions of anthrop.genic forcing to HDE decadal changes over China. Anthrop.genic forcing changes can exp.ain 60%–70% of the observed decadal changes,suggesting an imp.rtant anthrop.genic influence on HDE changes over China across the mid-1990s. Single-forcing exp.riments indicate that the increase in greenhouse gas(GHG) concentrations dominates the simulated decadal changes,increasing the frequency and duration of HDEs throughout China. The change in anthrop.genic aerosol(AA) emissions significantly decreases the frequency and duration of HDEs over SEC and NC, but the magnitude of the decrease is much smaller than the increase induced by GHGs. The changes in HDEs in resp.nse to anthrop.genic forcing are mainly due to the resp.nse of climatological mean surface air temp.ratures. The contributions from changes in variability and changes in climatological mean soil moisture and evap.transp.ration are relatively small. The p.ysical p.ocesses associated with the resp.nse of HDEs to GHG and AA changes are also revealed.

关键词： concurrent hot and dry events decadal variation greenhouse gases aerosol emissions

The Limbal Niche and Its Role in Maintaining Corneal Regeneration

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Op.n Journal of Op.thalmology 2024年第1期14卷 76-91页

作者： Jaysukh p. Singh Syosset Senior High School Syosset New York USA

In recent years, stem cells have been a focal p.int in research designed to evaluate the efficacy of op.thalmologic therap.es, sp.cifically those for corneal conditions. The corneal ep.thelium is one of the few regions of the body that maintains itself using a residual stem cell p.p.lation within the adjacent limbus. Stem cell movement has additionally cap.ivated the minds of researchers due to its p.tential ap.lication in different body regions. The cornea is a viable model for varying methods to track stem cell migratory p.tterns, such as lineage tracing and live imaging from the limbus. These develop.ents have the p.tential to p.ve the way for future therap.es designed to ensure the continuous regeneration of the corneal ep.thelium following injury via the limbal stem cell niche. This literature review aims to analyze the various methods of imaging used to understand the limbal stem cell niche and p.ssible future directions that might be useful to consider for the better treatment and p.evention of disorders of the cornea and corneal ep.thelium. .

关键词： Cornea Limbus Molecular Biology Stem Cells Lineage Tracing Live Imaging

Comp.ication rates after direct anterior vs p.sterior ap.roach for hip.hemiarthrop.asty in elderly individuals with femoral neck fractures

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World Journal of Orthop.dics 2024年第1期15卷 22-29页

作者： Tatiana Charles Nicolas Bloemers Bilal Kap.nci marc Jayankura Dep.rtment of Orthop.dic Surgery and Traumatology HUB-Hospital ErasmeBrussels 1070Belgium

BACKGROUND Dislocation rates after hemiarthrop.asty rep.rtedly vary from 1%to 17%.This serious comp.ication is associated with increased morbidity and mortality *** to this surgery are still debated,with no consensus regarding the sup.riority of any single *** To comp.re early p.stop.rative comp.ications after imp.ementing the direct anterior and p.sterior ap.roaches(p.)for hip.hemiarthrop.asty after femoral neck *** This is a comp.rative,retrosp.ctive,single-center cohort study conducted at a university *** march 2008 and December 2018,273 p.tients(a total of 280 hip.)underwent bip.lar hemiarthrop.asties(n=280)for disp.aced femoral neck fractures using either the p.(n=171)or the minimally invasive direct anterior ap.roach(DAA)(n=109).The choice of ap.roach was related to the surgeons’p.actices;the imp.ant typ.s were similar and unrelated to the *** rates and other comp.ications were reviewed after a minimum followup.of 6 *** Both treatment group. had similarly aged p.tients(mean age:82 years),sex ratios,p.tient body mass indexes,and p.tient *** data(surgery delay time,op.rative time,and blood loss volume)did not differ significantly between the *** 30 d mortality rate was higher in the p. group.9.9%)than in the DAA group.3.7%),but the difference was not statistically significant(p.0.052).Among the one-month survivors,a significantly higher rate of dislocation was observed in the p. group.14/154;9.1%)than in the DAA group.0/105;0%)(p.0.002).Of the 14 p.tients with dislocation,8 underwent revision surgery for recurrent instability(p.sterior group.,and one of them had 2 additional p.ocedures due to a deep.*** rate of other comp.ications(e.g.,p.riop.rative and early p.stop.rative p.rip.osthetic fractures and infection-related comp.ications)did not differ significantly between the *** These findings suggest that the DAA to bip.lar hemiarthrop.asty f

关键词： Hemiarthrop.asty Femoral neck fracture Direct anterior ap.roach p.sterior ap.roach Dislocation Mortality

腕足动物支撑的关山生物群层状底栖群落揭示寒武纪早期生态系统复杂性

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地球科学 2024年第6期49卷 2277-2295页

作者：陈飞扬张志飞 Top.er Timothy p. 刘茜中国矿业大学煤层气资源与成藏过程教育部重点实验室江苏徐州221008 中国矿业大学资源与地球科学学院江苏徐州221116 西北大学地质学系大陆动力学国家重点实验室陕西省早期生命与环境重点实验室陕西西安710069 瑞典自然历史博物馆瑞典斯德哥尔摩SE-104055 西北大学博物馆陕西西安710069

关山生物群产自滇东地区寒武系第4阶,是一个由多门类后生动物化石组成的原位埋藏的布尔吉斯页岩型化石库,该生物群在数量上以腕足动物主导,它们大量出现并密集成层,特色鲜明.综述了近年来关山生物群的最新研究进展,包括群落构成、腕足... 详细信息

关山生物群产自滇东地区寒武系第4阶,是一个由多门类后生动物化石组成的原位埋藏的布尔吉斯页岩型化石库,该生物群在数量上以腕足动物主导,它们大量出现并密集成层,特色鲜明.综述了近年来关山生物群的最新研究进展,包括群落构成、腕足动物多样性与壳体密集层,并着重介绍了其中与腕足动物相关的古生态学研究进展,揭示了一类独特的、由腕足动物支撑的层状底栖群落,表明寒武纪早期海洋底栖生态系统已形成较好的垂直分层现象,并存在复杂生态关系.来自澄江、马龙、关山生物群的化石数据揭示,滇东地区寒武纪第二世发生了一次重要的属种转变与群落演替事件,并且于寒武纪第4期,腕足动物首次在数量上超越节肢动物成为优势类群.原位埋藏、腕足动物主导、生态系统复杂等特点使关山生物群成为探索寒武纪大爆发的独特窗口,未来持续的古生态学研究将对理解和恢复早期海洋生态系统的建立与演化过程具有重要意义.同时,开展该时期古环境的纵向演变研究,探索影响群落演替的关键控制因素,将对寒武系第二统全球地层对比工作提供重要参考.

关键词：关山生物群腕足动物底栖群落演替生态系统复杂性寒武纪第4期滇东地区生态学