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Chinese Physics C 2024年第4期48卷 6-13页

作者： Y.mahmoud H.Abdallah m.t.Hussein S.Elgammal Centre for theoretical physics The British University in EgyptEgypt Physics Department Faculty of ScienceCairo UniversityEgypt

In this study,we conducted a search for dark matter using a part of the data recorded by the CmS experiment during run-I of the LHC in 2012 with a center of mass energy of 8 teV and an integrated luminosity of 11.6 fb−*** data were gathered from the CmS open *** matter,in the framework of the simplified model(mono-Z′),can be produced from proton-proton collisions in association with a new hypothetical gauge boson,Z′.thus,the search was conducted in the dimuon plus large missing transverse momentum *** benchmark scenario of mono-Z′,which is known as light vector,was used for interpreting the CmS open *** evidence of dark matter was observed,and exclusion limits were set on the masses of dark matter and Z′at 95%confidence level.

关键词： dark matter large hadron collider CmS open data search for new physics dark fermion

Hard yet tough and self-lubricating(CuNitiNbCr)C_(x) high-entropy nanocomposite films:Effects of carbon content on structure and properties

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Journal of materials Science & technology 2024年第6期173卷 20-30页

作者： Y.t.Li X.m.Chen X.K.Zeng m.Liu X.Jiang Y.X.Leng Key Laboratory of Advanced technologies of materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China Key Laboratory of Noise and Vibration Research Institute of AcousticsChinese Academy of SciencesBeijing 100190China State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China School of mechanical and Electrical Engineering Mianyang Teachers’CollegeMianyang 621000China

the single-phase high-entropy alloy film is difficult to meet severe friction conditions due to its low hardness and high friction ***-composite structure film is composed of at least two separated phases,showing the properties of strength and toughness integration and excellent wear *** design of nanocomposite structures can effectively improve the mechanical properties and tribological properties of high-entropy alloy *** this study,the(CuNitiNbCr)C_(x) nanocomposite high-entropy films(HEFs)integrated with high hardness,high toughness,and self-lubrication were synthesized by the double-target co-sputtering *** effect of carbon content on microstructure,mechanical properties,and tribological properties of(CuNitiNbCr)C_(x) films was *** the increase of carbon content in the HEFs,the carbon atoms preferentially react with ti,Nb,and Cr to form a(tiNbCr)C ceramic-reinforced phase,and then the excess carbon atoms precipitate in the form of amorphous carbon(a-C)lubricating phase in the *** structure of the HEFs changes from an amorphous structure to a nanocomposite structure of amorphous(amorphous CuNitiNbCr phase+a-C phase)/nanocrystalline(tiN-bCr)C *** the carbon content is about 21.2 at.%,the carbide phase in the film reaches saturation and the hardness and modulus of the films are highest,which are 18 GPa and 228 GPa,*** HEFs with a carbon content of 44.0 at.%show the best toughness and tribological properties with a friction coefficient of 0.16 and a wear rate of 2.4×10^(-6) mm^(3)/(N m),which is mainly attributed to the excellent resistance to fatigue crack growth and the interfacial lubricating layer formed in the friction *** nanocomposite(CuNitiNbCr)C_(x) HEFs show very promising application prospect in the field of friction protection.

关键词： High-entropy films Nanocomposite Double-target co-sputtering Strengthening-toughening tribological properties

multi-scale habitat influences sprainting and group size of a freshwater-obligate smooth-coated otter(Lutrogale perspicillata) in tungabhadra Otter Conservation Reserve, India

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Ecological Processes 2024年第1期13卷 159-175页

作者： Ankit moun P.Ramesh Kumar m.malathi Priya t.Ramesh riddhika Kalle Sálim Ali Centre for Ornithology and Natural History Deputy Conservator of Forests Bellary Territorial Forest Division Deputy Conservator of Forests Working Plan and Survey and Research WingBellary Territorial Forest Division Centre for Functional Biodiversity University of Kwa Zulu-Natal

Background the impact of changing land-use patterns and associated anthropogenic threats on scale-dependent habitat use of semi-aquatic mustelids in scent-marking and social behaviour can provide important insights into the habitat ecology of smooth-coated otters(Lutrogale perspicillata).methods We sampled 180 stream segments(100–400 m) as spatial replicates of 60 1-km2 sites to record indirect evidence(i.e. spraints and mass latrine sites) and group sizes of smooth-coated otters along the tungabhadra Otter Conservation Reserve(tOCR) during the dry season. to quantify habitat, we recorded stream characteristics, riparian vegetation, and anthropogenic disturbances at the local scale, and hydro-environmental characteristics and land uses at the landscape scale. Using markovian-chain detection and occupancy models, we assessed the multi-scale habitat use of otters in their selection of suitable areas for scent-marking based on repeated presence-absence data on spraint/latrine locations along the tOCR. We further used linear regression techniques to explore relationships between the number of individuals in smooth-coated otter group and hydro-environmental characteristics, spraint/latrine encounter rate, anthropogenic pressure, land cover, topography, and *** At the local scale, the probability of spraint deposition and group size decreased with anthropogenic disturbance while the probability of spraint detections decreased with grass cover. At the landscape scale, the probability of otter site use for spraint deposition and group sizes increased in southeast flowing streams. Spraint deposition increased with the proportion of sugarcane fields, whereas in contrast, group size decreased with proportion of sugarcane *** Our findings highlight the first empirical evidence on multi-scale habitat use of a southern Indian population of smooth-coated otters in an inland freshwater ecosystem surrounded by the scrub jungle–agriculture matrix. We sug

关键词： Presence-absence modelling Inland river Freshwater ecosystem Semi-aquatic mammal Smooth-coated otter

Biosynthesized CS-mgO/zeolite hybrid material:An efficient adsorbent for chlorpyrifos removal-Kinetic studies and response surface methodology

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Emerging Contaminants 2024年第3期10卷 304-317页

作者： mohammed t.m.H.Hamad Belal N.A.mahran Central Laboratory for Environmental Quality monitoring National Water Research CenterEgypt

the prevalence of organophosphate pesticides in aquatic environments raises severe concerns on a global ***,an insecticide,is included in a class of organophosphate *** is widely used on agricultural lands to control pests in cotton,fruit,and *** acute toxicity of chlorpyrifos is still dangerous to all aquatic living *** the treatment of water contaminated with chlorpyrifos is an important *** recent decade has witnessed adsorption technology emerging as an advanced organophosphate pesticide wastewater treatment with great potential and a grand blueprint,in which the specific surface area and active sites of the adsorbent are considered to be the two most important characteristics largely impacting the adsorption *** this study,a CS-mgO/Zeolite composite was prepared by the microbial method as an effective adsorbent for the removal of chlorpyrifos from an aqueous *** adsorbent's properties were carefully characterized using Xray diffraction,scanning electron microscopy,and Fourier-transform infrared *** refinement of experimental conditions,encompassing variations in adsorbent dosage,contact time,and chlorpyrifos concentration at five discrete levels,was systematically undertaken through the utilization of a composite central design rooted in response surface *** solution pH played a key role in chlorpyrifos removal,and a pH of 7.0 was selected according to its high adsorption *** highest removal(80.9%)of chlorpyrifos by CS-mgO/Zeolite was obtained at an optimum pH of 7,a contact time of 40 min,an adsorbent dosage of 0.4 g/L,and a chlorpyrifos concentration of 5 mg/L^(-1).the adsorption results were highly fitted with the Freundlich adsorption isotherm model,and the maximum adsorption was 83.3 mg/*** studies indicate that the removal of chlorpyrifos followed the pseudo-secondorder model of adsorption(0.994).the thermodynamic parameters indicate the sponta

关键词： Chlorpyrifos adsorption CS-mgO/Zeolite Response surface methodology

Clinical validation of the early embryo viability assessment system: Analysis for the blastocyst morphology and pregnancy outcomes

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Asian pacific Journal of Reproduction 2024年第5期13卷 219-227页

作者： Vu D Hop An m Cuong Phi t t Anh Nguyen t L Huong Le Hoang Nguyen V Hanh Assisted Reproductive technology Centre Tam Anh General HospitalHanoiVietnam Institute of Biotechnology Vietnam Academy of Science and TechnologyHanoiVietnam

Objective:to determine the relationship between the early embryo viability assessment(EEVA)and blastocyst morphological parameters and pregnancy ***:this retrospective cohort study was conducted on 291 intracytoplasmic sperm injection cycles including 2522 embryos with indications of prolonging embryo culture to the blastocyst stage in the Genea embryo review incubator,and 511 single vitrified-warmed blastocyst transfer cycles from January 2020 to June *** EEVA system produced an EEVA score from E1(best)to E5(worse)for the potential of blastocyst *** morphology was *** association between the EEVA score and each type of blastocyst morphology,implantation rate,clinical pregnancy,and ongoing pregnancy were assessed using generalized estimating ***:the inner cell mass A(ICm A),trophectoderm A(tE A),blastocoele expansion degree of 3,4,5,6,7 rates were higher with lower the EEVA *** adjusted odd ratio(aOR)(E5 vs E1)was 0.3 for ICm A,0.174 for tE A and 0.210 for BL3,4,5,6,7(all Pting a significant association between lower EEVA scores and improved embryo *** implantation,clinical pregnancy,and ongoing pregnancy rate were also higher with lower the EEVA *** aOR of E5 vs E1 was 0.245 for implantation,0.185 for clinical pregnancy and 0.200 for ongoing pregnancy rate(Pthere were associations between blastocyst morphology,pregnancy outcome and EEVA *** good blastocyst morphology and pregnancy outcomes are higher with lower the EEVA score.

关键词： Automated embryo assessment Blastocyst Early embryo viability assessment Genea embryo review incubator

SmILE soft X-ray Imager flight model CCD370 pre-flight device characterisation

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Earth and Planetary Physics 2024年第1期8卷 25-38页

作者： S.Parsons D.J.Hall O.Hetherington t.W.Buggey t.Arnold m.W.J.Hubbard A.Holland Centre for Electronic Imaging the Open UniversityMilton KeynesMK76AAUK

throughout the SmILE mission the satellite will be bombarded by radiation which gradually damages the focal plane devices and degrades their *** order to understand the changes of the CCD370s within the soft X-ray Imager,an initial characterisation of the devices has been carried out to give a baseline performance *** CCDs have been characterised,the two flight devices and the flight spa *** has been carried out at the Open University in a bespo ke cleanroom measure ment *** results show that there is a cluster of bright pixels in the flight spa re which increases in size with tempe *** at the nominal ope rating tempe rature(-120℃) it is within the procure ment ***,the devices meet the specifications when ope rating at -120℃ in 6 × 6 binned frame transfer science *** se rial charge transfer inefficiency degrades with temperature in full frame *** any charge losses are recovered when binning/frame transfer is implemented.

关键词： CCD soft X-ray imager characterisation SmILE

Comparative impact behaviours of ultra high performance concrete columns reinforced with polypropylene vs steel fibres

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Defence technology（防务技术） 2024年第10期40卷 138-153页

作者： thong m.Pham Harrison Hyde maw K.Kaung Yan Zhuge Duong t.tran Des Vlietstra tung m.tran UniSA STEMUniversity of South AustraliaMawson LakesSA 5095Australia BG&E Pty Ltd Wellington StreetPerthWA6000Australia Austral Construction Pty Ltd St Georges TerracePerthWA6000Australia Centre for Infrastructural monitoring and Protection(CImP) Curtin UniversityKent StBentleyWA 6102Australia Barchip Australia Pty Ltd U 26 Qualtroughq StreetWoolloongabbaQueensland4102Australia Sustainable Developments in Civil Engineering Research Group Faculty of Civil EngineeringTon Duc Thang UniversityHo Chi Minh City72915Viet Nam

Polypropylene(PP)fibres have primarily used to control shrinkage cracks or mitigate explosive spalling in concrete structures exposed to fire or subjected to impact/blast loads,with limited investigations on capacity *** study unveils the possibility of using PP micro-fibres to improve the impact behaviour of fibre-reinforced ultra-high-performance concrete(FRUHPC)*** show that the addition of fibres significantly improves the impact behaviour of FRUHPC columns by shifting the failure mechanism from brittle shear to favourable flexural *** addition of steel or PP fibres affected the impact responses *** fibres considerably increased the peak impact force(up to 18%)while PP micro-fibres slightly increased the peak(3%-4%).FRUHPC significantly reduced the maximum midheight displacement by up to 30%(under 20impact)and substantially improved the displacement recovery by up to 100%(under 20impact).FRUHPC with steel fibres significantly improved the energy absorption while those with PP micro-fibres reduced the energy absorption,which is different from the effect of PP-macro fibre reported in the *** optimal fibre content for micro-PP fibres is 1%due to its minimal fibre usage and low peak and residual *** study highlights the potential of FRUHPC as a promising material for impact-resistant structures by creating a more favourable flexural failure mechanism,enhancing ductility and toughness under impact loading,and advancing the understanding of the role of fibres in structural performance.

关键词： Ultra high-performance concrete Steel fibre Polypropylene micro-fibre Fibre volume fraction Impact loading Pendulum tests Columns

Comparative Orotomy of the Archean Superior, North China, and Phanerozoic Altaid Orogenic Systems Architecture

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Acta Geologica Sinica(English Edition) 2024年第S1期 33-35页

作者： t.m.KUSKY A.m.C.?ENG?R Center for Global tectonics School of Earth Sciences and State Key Laboratory for Geological Processes and Mineral Resources China University of Geosciences Eurasia Institute of Earth Sciences Istanbul Technical University Department of Geology Faculty of Mines Istanbul Technical University

Geological maps encode vast amounts of data about rock types, ages, chemistry, orogenic architecture and deep-time history or different tectonic units, yet these are often difficult to extract because of the way different geologists portray their results at various scales. to understand orogenesis in 4D, it is essential to uniformly integrate map data, together with geophysical data and deep geochemical mapping(Wang et al., 2023).

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Late Ordovician mass Extinction: Earth, fire and ice

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National Science Review 2024年第1期11卷 51-65页

作者： David A.t.Harper Palaeoecosystems Group Department of Earth SciencesDurham University

the Late Ordovician mass Extinction was the earliest of the ‘big’ five extinction events and the earliest to affect the trajectory of metazoan life. two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and introduced toxic bottom waters onto the shelves. these symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian, suggesting the extinctions were more protracted and influential than hitherto documented.

关键词： Ordovician LOmE paleoecology palaeobiogeography biotas

Development of an ultrathin liquid sheet target for laser ion acceleration at high repetition rates in the kilohertz range

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High Power Laser Science and Engineering 2024年第3期12卷 134-145页

作者： m.Füle A.P.Kovács t.Gilinger m.Karnok P.Gaál S.Figul G.marowsky K.Osvay National Laser-Initiated transmutation Laboratory University of SzegedSzegedHungary Department of Experimental Physics University of SzegedSzegedHungary ELI ALPS ELI-HU Non-Profit Ltd.SzegedHungary Department of Optics and Quantum Electronics University of SzegedSzegedHungary Advanced microfluidic Systems GmbH GöttingenGermany

A colliding microjet liquid sheet target system was developed and tested for pairs of round nozzles of 10,11 and 18μm in *** sheet's position stability was found to be better than a few *** interaction with 50 mJ laser pulses,the 18μm jet has a resonance amplitude of 16μm at a repetition rate of 33 Hz,while towards 100 Hz it converges to 10μm for all nozzles.A white-light interferometric system was developed to measure the liquid sheet thickness in the target chamber both in air and in vacuum,with a measurement range of 182 nm±1μm and an accuracy of±3%.the overall shape and 3D shape of the sheet follow the Hasson±Peck model in *** vacuum versus air,the sheet gradually loses 10%of its thickness,so the thinnest sheet achieved was below 200 nm at a vacuum level of 10±4mbar,and remained stable for several hours of operation.

关键词： diagnostics laser ion acceleration nanometric liquid sheet targets vacuum test