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Chinese Journal of Chemistry 2024年第6期42卷 652-685页

作者： Tharinee Theerathanagorn Tanika Kessaratikoon Hafeez Ur Rehman Valerio d'Elia d.n.el Crespy VISTEC Advanced Laboratory for Environment-Related Inorganic and Organic Syntheses Department of Materials Science and EngineeringVidyasirimedhi Institute of Science and Technology21210Wang ChanRayongThailand department of Materials Science and Engineering Vidyasirimedhi Institute of Science and Technology21210Wang ChanRayongThailand

Polyhydroxyurethanes(PHUs)have received considerable attention in the last decade as potential alternatives to traditional phosgene-based polyurethanes(PUs).The development of suitable 5CC(five membered-ring cyclic carbonate)precursors bearing multiple carbonate moieties(multi-5CCs)is a key requisite for preparing PHUs by polyaddition reaction with bis-or *** sustainable PHUs from CO_(2)-based five-membered cyclic carbonates(5CCs)obtained from biobased epoxides is a valuable strategy to bridge CO_(2) utilization and the upcycling of renewable *** this context,while many multi-5CC monomers reported in the literature are oil-based,recent efforts have led to the development of a large variety of multifunctional 5CCs that are produced by the combination of CO_(2) and renewable resources such as fatty acids and vegetable oils,lignin,terpenes,and *** this work,recent crucial advances(2019—2023)on PHUs prepared from bis-and multi-5CCs produced from CO_(2) and(partially/potentially)biobased substrates are reviewed with respect to their synthesis,thermal and mechanical properties,and their recent,emerging applications.

关键词： CO_(2) conversion Polyhydroxyurethanes Cyclic carbonates Biobased compounds Fatty acids Functional polymers Monomers Renewable resources

Radioisotope production using lasers:From basic science to applications

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Matter and Radiation at Extremes 2024年第3期9卷 31-44页

作者： M.R.d.Rodrigues A.Bonasera M.Scisciò J.A.Pérez-Hernández M.Ehret F.Filippi P.L.Andreoli M.Huault H.Larreur d.Singappuli d.Molloy d.Raffestin M.Alonzo G.G.Rapisarda d.Lattuada G.L.Guardo C.Verona Fe.Consoli G.Petringa A.Mcnamee M.La Cognata S.Palmerini T.Carriere M.Cipriani G.di Giorgio G.Cristofari R.de Angelis G.A.P.Cirrone d.Margarone L.Giuffrida d.Batani P.nicolai K.Batani R.Lera L.Volpe d.Giulietti S.Agarwal M.Krupka S.Singh Fa.Consoli Cyclotron Institute Texas A&M UniversityCollege StationTexas 77840USA Laboratori nazionali del Sud Istituto Nazionale di Fisica Nucleare(LNS-INFN)CataniaItaly EnEA Fusion and Technologies for Nuclear Safety and Security Department-CFrascatiItaly Centro de Láseres Pulsados(clpu) VillamayorSpain Universidad de Salamanca SalamancaSpain Centre Lasers Intenses et Applications(CELIA) Universitéde BordeauxCNRSCEATalenceFrance HB11 Energy Hold.n.s Pty FreshwaterNew South WalesAustralia School of Mathematics and Physics Queen’s University BelfastBelfastUnited Kingdom dipartimento di Fisica e Astronomia“E.Majorana ”Università di CataniaCataniaItaly Facoltàdi Ingegneria e Architettura Universitàdegli Studi di Enna“Kore”EnnaItaly dipartimento di Ingegneria Industriale Universitàdi Roma“Tor Vergata”RomaItaly dipartimento di Fisica e Geologia Universitàdegli Studi di PerugiaPerugiaItaly Istituto nazionale di Fisica nucleare Sezione di PerugiaPerugiaItaly ELI Beamlines Facility the Extreme Light Infrastructure ERICDolni BrezanyCzech Republic ETSIA Universidad Politécnica de MadridMadridSpain dipartimento Fisica “E.Fermi”Universitàdi Pisa and INFNPisaItaly FZU–Institute of Physics of Czech Academy of Sciences PragueCzech Republic Institute of Plasma Physics of Czech Academy of Sciences PragueCzech Republic

The discovery of chirped pulse amplification has led to great improvements in laser technology,enabling energetic laser beams to be compressed to pulse durations of tens of femtoseconds and focused to a few *** with energies of tens of MeV can be accelerated using,for instance,target normal sheath acceleration and focused on secondary *** such conditions,nuclear reactions can occur,with the production of radioisotopes suitable for medical *** use of high-repetition lasers to produce such isotopes is competitive with conventional methods mostly based on *** this paper,we study the production of^(67)Cu,^(63)Zn,^(18)F,and^(11)C,which are currently used in positron emission tomography and other *** the same time,we study the reactions^(10)B(p,α)^(7)Be and^(70)Zn(p,4n)^(67)Ga to put further constraints on the proton distributions at different angles,as well as the reaction^(11)B(p,α)^(8)Be relevant for energy *** experiment was performed at the 1 PW laser facility at VegaⅢin Salamanca,*** distributions of radioisotopes in the forward(with respect to the laser direction)and backward directions were measured using a high purity germanium *** results are in reasonable agreement with numerical estimates obtained following the approach of Kimura and Bonasera[*** ***.,Sect.A 637,164–170(2011)].

关键词： purity estimates backward

dFT investigation of half-metallic ferromagnetic rare earth based spinels MgHo_(2)Z_(4)(Z=S,Se)

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Journal of Rare Earths 2024年第1期42卷 121-128,I0005页

作者： Maiza Zanib Mumtaz Manzoor n.A.noor M.Waqas Iqbal Mazia Asghar H.H.Hegazy A.Laref department of Physics Riphah International UniversityLahore CampusPakistan Research Centre for Advanced Materials Science King Khalid UniversityP.O.Box 9004AbhaSaudi Arabia department of Physics Faculty of ScienceKing Khalid UniversityP.O.Box 9004AbhaSaudi Arabia department of Physics and Astronomy College of ScienceKing Saud UniversityRiyadh11451Saudi Arabia

Half-metallic ferromagnetism,mechanical as well as thermoelectric properties for rare earth-based spinels MgHo_(2)Z_(4)(Z=S,Se)were investigated using d.n.ity functional theory(dFT).Structural optimization was d.n. with Perdew-Burke-Ehrenzorf(PBE)sol-generalized gradient approximation(GGA)to calculate the lattice constant of both spinels comparable to experimental *** addition,Born stability criteria and.n.gative formation energy show that our studied spinels are also structurally and d.n.mically stable in the cubic *** ferromagnetic(FM)state stability,we also calculated the energy differences among FM,antiferromagnetic(AFM),and.n.n-magnetic(nM)***,Curie temperatures of ferromagnetic phases were also *** used Trans-Blaha improved BeckeJohnson(TB-mBJ)potential functional for electronics as well as magnetic characteristics,which lead to the consistent explanation of half-metallic ferromagnetism,representing the whole band-occupancy in material with exact detail of d.n.ity of states(dOS).The stable FM state was examined in spinels due to the exchange splitting of Ho cation consisting of p-d hybridizations compatible with the result achieved for electronics band structure and ***,spin magnetic moment was explained in terms of anion,cation,and sharing charge on studied *** addition,the calculated thermoelectric properties clearly show that operation range of these systems may be utilized by future experimental works for id.n.ifying the potential applications of these systems.

关键词： Ho-based spinels dFT simulations Mechanical parameters Electronic properties HM ferromagnetism Figure of merit

Ammonia and greenhouse gas distribution in a dairy barn during warm periods

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Frontiers of Agricultural Science and Engineering 2024年第3期11卷 428-441页

作者： Provvid.n.a Rita d’URSO Claudia ARCIdIACOnO Giovanni CASCOnE department of Agriculture Food and EnvironmentUniversity of CataniaVia S.Sofia n.100Catania 95123Italy

This research aimed to quantify concentrations of ammonia(nH3),carbon dioxide(CO_(2))and methane(CH_(4)),estimate emissions,and analyze the factors influencing them during warm periods in an open dairy barn equipped with two cooling systems in a Mediterranean climate *** distribution within the barn was observed to vary both vertically and horizontally,with the highest gas concentrations observed in the central area of the ***_(3),CH_(4)and CO_(2)ranged in 1.7–7.4,7–18,560–724μg·g^(–1),*** ventilation through openings and the operation of cooling systems induced changes in indoor microclimate conditions,influencing cow behavior and,consequently,gas *** concentrations were the highest at air velocities below 0.5 m·s^(–1).The highest concentration of nH_(3)was observed when the temperature-humidity index(THI)was>72 and≤78;and CO_(2)and CH_(4)concentrations were the highest with THI≥72 and decreased with THI≤***_(3)concentrations when barn management included three daily milkings were higher than those measured when barn management was based on two daily milkings,and lower for CH_(4)and CO_(2).nH_(3)and CH_(4)emissions were the highest during barn cleaning,while the lowest nH_(3)emissions occurred during activity of the cows(i.e.,feed.n.,walking).

关键词： Ammonia greenhouse gas environmental monitoring cows’behavior barn management housing system climatic parameters

Converting TREx-RGB green-channel data to 557.7 nm auroral intensity:Methodology and initial results

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Earth and Planetary Physics 2024年第1期8卷 258-274页

作者： Jun Liang d.M.Gillies E.Spanswick E.F.d.n.van University of Calgary CalgaryT2N 1N4Canada

The recently deployed Transition Region Explorer(TREx)-RGB(red-green-blue)all-sky imager(ASI)is designed to capture“true color”images of the aurora and *** the 557.7 nm green line is usually the brightest emission line in visible auroras,the green channel of a TREx-RGB camera is usually dominated by the 557.7 nm *** this rationale,the TREx mission does not include a specific 557.7 nm imager and is designed to use the RGB green-channel data as a proxy for the 557.7 nm *** this study,we present an initial effort to establish the conversion ratio or formula linking the RGB green-channel data to the absolute intensity of 557.7 nm auroras,which is crucial for quantitative uses of the RGB *** illustrate two approaches:(1)through a comparison with the collocated measurement of green-line auroras from the TREx spectrograph,and(2)through a comparison with the modeled green-line intensity accord.n. to realistic electron precipitation flux measurements from low-Earth-orbit satellites,with the aid of an auroral transport *** demonstrate the procedures and provide initial results for the TREx-RGB ASIs at the Rabbit Lake and Lucky Lake *** RGB response is found to be *** conversion ratios or formulas between RGB green-channel data and the green-line auroral intensity are given and can be applied immediately by TREx-RGB data *** methodology established in this study will also be applicable to the upcoming SMILE ASI mission,which will adopt a similar RGB camera system in its deployment.

关键词： TREx RGB green-line aurora auroral transport model

Prevalence of visual impairment and estimation of refractive errors among school children in Kakamega,Kenya

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 932-939页

作者： Isabel Signes-Soler Alfred Ragot Sheilah nangena Andrew Wekesa Raúl Montalbán Llamusí department of Optics and Optometry and Vision Sciences Universidat de ValènciaBurjassotValencia 46010Spain nGO Vision Without Borders(Visio Sense Fronteres VSF)Calpe 03710AlicanteSpain Masinde Muliro University of Science and Technology P.O Box 190-50100KakamegaKenya Clinica Baviera Alicante C/Ausóy Monzó 16Alicante 03006Spain

AIM:To investigate the prevalence of visual impairment(VI)and provide an estimation of uncorrected refractive errors in school-aged children,conducted by optometry stud.n.s as a community ***:The study was *** 3343 participants were included in the *** initial examination involved assessing the uncorrected distance visual acuity(UdVA)and visual acuity(VA)while using a+2.00 d *** inclusion criteria for a subsequent comprehensive cycloplegic eye examination,performed by an optometrist,were as follows:a UdVAdecimal(0.20 logMAR)and/or a VA with+2.00 d≥0.8 decimal(0.96 logMAR).RESULTS:The sample had a mean age of 10.92±2.13y(range 4 to 17y),and 51.3%of the children were female(n=1715).The majority of the children(89.7%)fell within the age range of 8 to *** the ethnic groups,the highest representation was from the Luhya group(60.6%)followed by Luo(20.4%).Mean logMAR UdVA choosing the best eye for each stud.n. was 0.29±0.17(range 1.70 to 0.22).Out of the total,246 participants(7.4%)had a full eye *** estimated prevalence of myopia(defined as spherical equivalent≤-0.5 d)was found to be 1.45%of the total *** around 0.18%of the total sample had hyperopia value exceed.n.+1.75 *** astigmatism(cild)was found in 0.21%(7/3343)of the *** VI prevalence was 1.26%of the total *** our cases of VI,76.2%could be attributed to uncorrected refractive *** was detected in 0.66%(22/3343)of the screened *** was no statistically significant correlation observed between age or gender and refractive ***:The primary cause of VI is determined to be uncorrected refractive errors,with myopia being the most prevalent refractive error *** find.n.s underscore the significance of early id.n.ification and correction of refractive errors in school-aged children as a means to alleviate the impact of VI.

关键词： visual impairment refractive errors myopia amblyopia sustainable development goals

Self-lubricating bidirectional carbon fiber reinforced smart aluminum composites by squeeze infiltration process

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Journal of Materials Science & Technology 2019年第11期35卷 2559-2569页

作者： K.M.Sree Manu L.Ajay Raag T.P.d.Rajan B.C.Pai Vijay petley Shweta namdeo Verma CSIR-national Institute for Interdisciplinary Science and Technology TrivandrumIndia Gas Turbine Research Establishment(GTRE) BangaloreIndia

Self-lubrication is one of the smart material properties required for producing components with enhanced wear resistance and low coefficient of ***(Bd)satin weave polyacrylonitrile(PAn)based carbon fiber(Cf)fabric preform was successfully infiltrated with Al 6061 alloy by squeeze infiltration *** infiltrated composite shows uniform distribution of carbon fibers in the matrix with the elimination of porosities,fiber damage and close control on the formation of deleterious aluminum carbide(Al4C3)***/Al composite exhibits remarkable wear resistance compared to unreinforced alloy due to the formation of self-lubricating tribolayer on the pin surface,which intercepts the contact of matrix metal to counter *** Bd carbon fiber enhanced the hardness and compressive strength of the composite by restraining the plastic flow behavior of *** resolution transmission electron microscopy shows the presence of Al2O3 and MgAl2O4 spinel,confirmed by EdS and SAd pattern,at the composite *** composite shows a lower d.n.ity of 2.16 g/cm^3 which is a major ad vantage for weight reduction compared to the monolithic alloy(2.7 g/cm^3).

关键词： Metal matrix composites Squeeze infiltration Aluminum Carbon fiber fabric Tribology Microstructure

numerical analysis of high‑speed railway slab tracks using calibrated and validated 3d time‑domain modelling

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Railway Engineering Science 2024年第1期32卷 36-58页

作者： A.F.Esen O.Laghrouche P.K.Woodward d.Med.n.‑Pineda Q.Corbisez J.Y.Shih d.P.Connolly Institute for High‑Speed Rail and System Integration University of LeedsLeeds LS29JTUK Institute for Infrastructure and Environment Heriot-Watt UniversityEdinburgh EH144ASUK Alstom Transport Saint‑OuenFrance Birmingham Centre for Railway Research and Education University of BirminghamBirmingham B152TTUK

Concrete slabs are widely used in modern railways to increase the inherent resilient quality of the tracks,provide safe and smooth rides,and reduce the maintenance *** this paper,the elastic performance of a novel slab trackform for high-speed railways is investigated using three-dimensional finite element modelling in *** is then compared to the performance of a ballasted ***,slab and ballasted track models are developed to replicate the full-scale testing of track *** the models are calibrated with the experimental results,the novel slab model is developed and compared against the calibrated slab track *** slab and ballasted track models are then extended to create linear d.n.mic models,considering the track geod.n.mics,and simulating train passages at various speeds,for which the Ledsgard documented case was used to validate the *** travelling at low and high speeds are analysed to investigate the track deflections and the wave propagation in the soil,considering the issues associated with critical *** train load.n. methods are discussed,and the most practical approach is retained and ***,correlations are made between the geotechnical parameters of modern high-speed rail and conventional *** is found that considering the same ground condition,the slab track deflections are considerably smaller than those of the ballasted track at high speeds,while they show similar behaviour at low speeds.

关键词： High-speed railways Slab track new ballastless track Ballasted track Critical speeds Finite element modelling Calibration of numerical models

Hydrophobic long-chain two-dimensional perovskite scintillators for underwater X-ray imaging

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Rare Metals 2024年第1期43卷 175-185页

作者： Jin-Xiao Zheng Zi-An Zhou Tiao Feng Hui Li Cheng-Hua Sun nüWang Yang Tian Yong Zhao Shu-Yun Zhou Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Laboratory of Bioinspired Smart Interfacial Science and Technology of the Ministry of Education Beijing Key Laboratory of Bioinspired Energy Materials and DevicesSchool of ChemistryBeijing Advanced Innovation Center for Biomedical EngineeringBeihang UniversityBeijing 100191China department of Engineering Physics Tsinghua University and Key Laboratory of Particle and Radiation Imaging Ministry of EducationTsinghua UniversityBeijing 100084China e-mail:yangt@***

The underwater X-ray imaging technology development is significant to subaqueous target reconnaissance/detection/id.n.ification, subfluvial archaeology,submerged resource exploration, etc. As the core of X-ray imaging detection, the scintillator has been plagued by inherent moisture absorption and decomposition, and strict requirements for seamless packaging and ***, we designed a manganese-doped two-dimensional(2d) perovskite scintillator modified by hydrophobic longchain organic amine through the combination of component and doping engineering. The modified perovskites show high water repellency that can be used as an underwater X-ray scintillator. X-ray images of aquatic organisms or other objects with a high spatial resolution of10 lp·mm^(-1) at a big view field(32 mm × 32 mm) were obtained by scintillation screen. This hydrophobic perovskite scintillator based on molecular design is of great promise in underwater X-ray nondestructive testing technology development.

关键词： Two-dimensional perovskite Hydrophobic Scintillators Underwater X-ray imaging Underwater nondestructive testing technology

Accuracy of tree mapping based on hand-held laser scanning comparing leaf-on and leaf-off conditions in mixed forests

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Journal of Forestry Research 2024年第5期35卷 14-25页

作者： Frederico Tupinambá-Simões Adrián Pascual Juan Guerra-Hernández Cristóbal Ordóñez Tiago de Conto Felipe Bravo iuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIAValladolidSpain department of Geographical Sciences University of MarylandCollege ParkMD 20742USA Forest Research Centre School of AgricultureUniversity of LisbonTapada da Ajuda1349‑017 LisbonPortugal

The use of mobile laser scanning to survey forest ecosystems is a promising,scalable technology to describe forest 3d structures at high *** confirm the con-sistency in the retrieval of forest structural parameters using hand-held laser scanning(HLS),before operationalizing the method,confirming the data is *** analyzed the per-formance of tree-level mapping based on HLS under differ-ent phenology conditions on a mixed forest in western Spain comprising Pinus pinaster and two deciduous species,Alnus glutinosa and Quercus *** area was surveyed twice during the growing season(July 2022)and once in the deciduous season(February 2022)using several scan-ning *** reference data(418 trees,15 snags)was used to calibrate the HLS data and to assess the influence of phenology when converting 3d data into tree-level attrib-utes(dBH,height and volume).The HLS-based workflow was robust at isolating tree positions and recognizing stems despite changes in ***-six percent of all pairs matched below 65 *** dBH,phenology barely altered *** observed a strong agreement when comparing HLS-based tree height *** values exceeded 2 m when comparing height measurements,confirming height data should be carefully used as reference in remote sensing-based inventories,especially for deciduous *** volume was more precise for pines(r=0.95,and rela-tive RMSE=21.3–23.8%)compared to deciduous species(r=0.91–0.96,and relative RMSE=27.3–30.5%).HLS data and the forest structural complexity tool performed remark-ably,especially in tree positioning considering mixed forests and mixed phenology conditions.

关键词： Precision forestry Forest monitoring Mobile laser scanning Forest inventory