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Efficient guiding and focusing of intense laser pulse using periodic thin slits

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Matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： L.Xu T.W.huang K.Jiang C.N.Wu h.Peng P.C.hen R.Li h.b.Zhuo C.T.Zhou Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material Technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental physics of intense laser interaction with thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing *** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

Spatiotemporal dynamics in butterfly hybrid zones

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Insect Science 2024年第2期31卷 328-353页

作者： Ananda R.Pereira Martins Natalie b.Warren W.Owen McMillan Rowan D.h.barrett Redpath Museum McGill University859 Sherbrooke Street WestMontrealQuebecCanada Smithsonian Tropical ResearchInstitute GamboaPanama CityPanama

Evaluating whether hybrid zones are stable or mobile can provide novelinsights for evolution and conservation biology. butterflies exhibit high sensitivity to envi-ronmental changes and represent an important model system for the study of hybrid zoneorigins and maintenance. here, we review the literature exploring butterfly hybrid zones,with a special focus on their spatiotemporal dynamics and the potential mechanisms thatcould lead to their movement or stability. We then compare different lines of evidenceused to investigate hybrid zone dynamics and discuss the strengths and weaknesses ofeach approach. Our goal with this review is to reveal general conditions associated withthe stability or mobility of butterfly hybrid zones by synthesizing evidence obtained us-ing different types of data sampled across multiple regions and spatial scales. Finally, wediscuss spatiotemporal dynamics in the context of a speciation/divergence continuum, therelevance of hybrid zones for conservation biology, and recommend key topics for futureinvestigation.

关键词： butterflies human impacts hybrid zones movement spatiotemporaldynamics stability

SARS-CoV-2 variants are associated with different clinical courses in children with MIS-C

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World Journal of Pediatrics 2024年第2期20卷 143-152页

作者： Andres F.Moreno Rojas Emelia bainto helen harvey Adriana h.Tremoulet Jane C.burns Kirsten b.Dummer Department of Pediatrics Division of Pediatric CardiologyUniversity of California San Diegoand Rady Children’s Hospital3020 Children’s Way MC 5004San DiegoCA 92123USA Kawasaki Disease Research Center La JollaCAUSA Department of Pediatrics Division of Pediatric Critical CareUniversity of California San Diegoand Rady Children’s HospitalSan DiegoCAUSA Department of Pediatrics University of California San Diegoand Rady Children’s HospitalSan DiegoCAUSA

background Recent infection with SARS‑CoV-2 in children has been associated with multisystem inflammatory syndrome in children(MIS-C).SARS‑CoV-2 has undergone different *** publications exist about specific variants and their correlation with the severity of *** This was a single-center,retrospective study including all patients admitted with MIS-C at Rady Children’s hospital-San Diego between May 2020 and March *** epidemiologic data,including viral genomic information,were obtained from public ***,clinical presentation,laboratory values,and outcomes were obtained from electronic medical *** The analysis included 104 pediatric *** MIS-C waves were *** variants in San Diego during the first wave included clades 20A to *** the second wave,there were variants from clades 20A to C,20G,21C(Epsilon),20I(Alpha),and 20J(Gamma).The third wave had Delta strains(clades 21A,21I,and 21J),and the fourth had Omicron variants(clades 21K,21L,and 22C).MIS-C presented with similar symptoms and laboratory findings across all *** patients were admitted to the pediatric intensive care unit(PICU)(74%)and required inotropic support(63%)during the second *** of the patients required mechanical circulatory support,and only two required invasive ventilatory *** was no *** The various strains of SARS-CoV-2 triggered MIS-C with differing severities,with the second wave having a more severe clinical *** the differences in disease severity across variants were due to changes in the virus or other factors remains unknown.

关键词： Complications COVID-19 MIS-C SARS-CoV-2 variants

Optimization of chemistry and process parameters for control of intermetallic formation in Mg sludges

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Journal of Magnesium and Alloys 2024年第4期12卷 1431-1448页

作者： Y.Fu G.G.Wang A.hu Y.Li K.b.Thacker J.P.Weiler h.hu Department of Mechanical Automotive and Materials EngineeringUniversity of Windsor401 Sunset AveWindsorOntario N9B 3P4Canada Global Technology Centre Meridian Lightweight Technologies25 MacNab AveStrathroyOntario N7G 4H6Canada

Intermetallic formation in sludge during magnesium(Mg)melting,holding and high pressure die casting practices is a very important ***,very often it is overlooked by academia,original equipment manufacturers(OEM),metal ingot producers and even die *** aim of this study was to minimize the intermetallic formation in Mg sludge via the optimization of the chemistry and process *** Al8Mn5 intermetallic particles were identified by the microstructure analysis based on the Al and Mn *** design of experiment(DOE)technique,Taguchi method,was employed to minimize the intermetallic formation in the sludge of Mg alloys with various chemical compositions of Al,Mn,Fe,and different process parameters,holding temperature and holding *** sludge yield(SY)and intermetallic size(IS)was selected as two *** optimum combination of the levels in terms of minimizing the intermetallic formation were 9 wt.%Al,0.15 wt.%Mn,0.001 wt.%(10 ppm)Fe,690℃ for the holding temperature and holding at 30 mins for the holding time,*** best combination for smallest intermetallic size were 9 wt.%Al,0.15 wt.%Mn,0.001 wt.%(10 ppm)Fe,630℃ for the holding temperature and holding at 60 mins for the holding time,*** groups of sludge factors,Chemical Sludge(CSF),Physical Sludge(PSF)and Comprehensive Sludge Factors(and CPSF)were established for prediction of sludge yields and intermetallic sizes in Al-containing Mg *** CPSF with five independent variables including both chemical elements and process parameters gave high accuracy in prediction,as the prediction of the PSF with only the two processing parameters of the melt holding temperature and time showed a relatively large deviation from the experimental *** Chemical Sludge Factor was primarily designed for small ingot producers and die casters with a limited melting and holding capacity,of which process parameters could be fixed *** Physical Sludge Factor could be used f

关键词： Magnesium sludge Al-Mn intermetallic Optimization Taguchi method Sludge factor Chemical composition Process parameter

Atomistic Investigation of Shock-Induced Amorphization within Micro-shear bands in hexagonal Close-Packed Titanium

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Acta Metallurgica Sinica(English Letters) 2024年第9期37卷 1590-1600页

作者： Z.C.Meng K.G.Wang T.Ali D.Li C.G.bai D.S.Xu S.J.Li A.h.Feng G.J.Cao J.h.Yao Q.b.Fan h.Wang R.Yang Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Interdisciplinary Centre for Additive Manufacturing(ICAM) School of Materials and ChemistryUniversity of Shanghai for Science and TechnologyShanghai 200093China School of Materials Science and Engineering Tongji UniversityShanghai 201804China Key Laboratory for Light-Weight Materials Nanjing Tech UniversityNanjing 210009China National Key Laboratory of Science and Technology on Materials Under Shock and Impact School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China beijing Institute of Technology Chongqing Innovation Center Chongqing 401135China

The mechanical response of a single crystal titanium sample against(0001)α surface impact was investigated using molecular dynamics ***,non-uniform plastic deformation was observed in the *** high strain rates,amorphization occurred near the edge of the contact region where severe shear strain induced a large number of stacking faults(SFs)and *** contrast,the central part of the contact region underwent less deformation with significantly fewer ***,instead of amorphization by consuming SFs and dislocations,there was a gradual increase in the density of dislocations and SFs during the process of *** local amorphous regions eventually grew into shear bands.

关键词： Shock compression Amorphization Shear band Titanium Molecular dynamics

Cellulose synthesis in land plants

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Molecular Plant 2024年第2期17卷 359-361页

作者： Gustav b.Pedersen Leonard blaschek Kristian E.h.Frandsen Lise C.Noack Staffan Persson 不详

After the original publication of the above article,we and/or attentive readers identified several instances of unclear or erroneous writing that needed correcting,as *** are added for emphasis.

关键词： synthesis instance identif

Greatly enhanced corrosion/wear resistances of epoxy coating for Mg alloy through a synergistic effect between functionalized graphene and insulated blocking layer

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Journal of Magnesium and Alloys 2024年第1期12卷 332-344页

作者： Z.Y.Xue X.J.Li J.h.Chu M.M.Li D.N.Zou L.b.Tong School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China State Key Laboratory of Advanced Design and Manufacturing for Vehicle body Hunan UniversityChangsha 410082China

The poor corrosion and wear resistances of Mg alloys seriously limit their potential applications in various *** conventional epoxy coating easily forms many intrinsic defects during the solidification process,which cannot provide sufficient *** the current study,we design a double-layer epoxy composite coating on Mg alloy with enhanced anti-corrosion/wear properties,via the spin-assisted assembly *** outer layer is functionalized graphene(FG)in waterborne epoxy resin(WEP)and the inner layer is Ce-based conversion(Ce)*** FG sheets can be homogeneously dispersed within the epoxy matrix to fill the intrinsic defects and improve the barrier *** Ce film connects the outer layer with the substrate,showing the transition *** corrosion rate of Ce/WEP/FG composite coating is 2131 times lower than that of bare Mg alloy,and the wear rate is decreased by~90%.The improved corrosion resistance is attributed to the labyrinth effect(hindering the penetration of corrosive medium)and the obstruction of galvanic coupling *** synergistic effect derived from the FG sheet and blocking layer exhibits great potential in realizing the improvement of multi-functional integration,which will open up a new avenue for the development of novel composite protection coatings of Mg alloys.

关键词： Mg alloy Functionalized graphene Epoxy coating Corrosion/wear resistance blocking layer

A novel diurnal and seasonal variation analysis of bTEX in bengaluru urban area

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Research in Cold and Arid Regions 2024年第1期16卷 14-19页

作者： h.N.Sowmya M.Dinamani G.P.Shivashankara h.K.Ramaraju b.S.Surendra Vijaya V.Shanbhag R.Prajwal Department of Civil Engineering Dayananda Sagar College of EngineeringBangalore 560078India Department of Chemistry Dayananda Sagar College of EngineeringBangalore 560078India Department of Physics GFGCVijayanagarBengaluru 560040India

In the urban atmosphere of bengaluru, various volatile organic compounds(VOCs), particularly benzene,Toluene, Ethylbenzene, and Xylene(bTEX), have shown an increasing trend in concentration. The present research was conducted during summer and monsoon seasons, focusing on Kadubeesanahalli, a high-traffic area within the bengaluru Metropolitan City. hourly sample data was collected using a bTEX analyzer(Model GC955-600) and subsequently transformed into daily, monthly, and seasonal values. The study revealed distinct patterns in benzene concentrations. benzene levels were lowest during the early morning hours, specifically from 1:00 *** 7:00 a.m.. Concentrations then increased from 7:00 a.m. to 9:00 a.m. and again from 4:00 p.m. to 11:00 p.m.,corresponding to the morning and evening peak traffic hours. however, between 10:00 a.m. and 4:00 p.m., the concentration decreased due to reduced traffic levels. These diurnal variations in benzene concentration are influenced by meteorological parameters. Comparing the two seasons, higher concentrations of benzene, Ethylbenzene, and MP-xylene were observed during the summer season. This increase is attributed to the elevated temperatures during summer, which promote the vaporization of bTEX compounds. Conversely, lower bTEX concentrations were recorded during the monsoon season due to the wet deposition process. The observed positive correlation(r > 0.5) among bTEX parameters strongly suggests a common source, most likely originating from vehicular emissions.

关键词： bTEX Summer variation Meteorological parameters Correlation

A concise review on surface and structural modification of porous zeolite scaffold for enhanced hydrogen storage

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Chinese Journal of Chemical Engineering 2024年第6期70卷 33-53页

作者： b.A.Abdulkadir R.S.R.Mohd Zaki A.T.Abd Wahab S.N.Miskan Anh-Tam Nguyen Dai-Viet N.Vo h.D.Setiabudi Centre for Research in Advanced Fluid&Processes Universiti Malaysia Pahang Al-Sultan AbdullahLebuh Persiaran Tun Khalil YaakobGambangPahang 26300Malaysia Faculty of Chemical&Process Engineering Technology Universiti Malaysia Pahang Al-Sultan AbdullahLebuh Persiaran Tun Khalil YaakobGambangPahang 26300Malaysia Center of Excellence for Green Energy and Environmental Nanomaterials(CE@GrEEN) Nguyen Tat Thanh University300A Nguyen Tat ThanhDistrict 4Ho Chi Minh City 755414Viet Nam

Investigating zeolites as hydrogen storage scaffolds is imperative due to their porous nature and favorable physicochemical ***,the storage capacity of the unmodified zeolites has been rather unsatisfactory(0.224%-1.082%(mass))compared to its modified ***,the contemporary focus on enhancing hydrogen storage capacities has led to significant attention towards the utilization of modified zeolites,with studies exploring surface modifications through physical and chemical treatments,as well as the integration of various active *** enhanced hydrogen storage properties of zeolites are attributed to the presence of aluminosilicates from alkaline and alkaline-earth metals,resulting in increased storage capacity through interactions with the charge density of these ***,there is a great demand to critically review their role such as well-defined topology,pore structure,good thermal stability,and tunable hydrophilicity in enhanced hydrogen *** article aimed to critically review the recent research findings based on modified zeolite performance for enhanced hydrogen *** of the factors affecting the hydrogen storage capacities of zeolites that can affect the rate of reaction and the stability of the adsorbent,like pressure,structure,and morphology were studied,and ***,future perspectives,recommendations,and directions for modified zeolites were discussed.

关键词： Zeolites hydrogen storage Surface modification Adsorption Active metal