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Science China Chemistry 2024年第11期67卷 3791-3797页

作者： d.basis Pal Kirana d.Veeranna Yuk Fai Wong P.And.ew Evans d.partment of Chemistry Queen's University Xiangya School of Pharmaceutical Sciences Central South University

The Reformatsky reagent d.rived.from ethyl bromoacetate circumvents the challenge associated.with the d.rect regio-and.enantioselective irid.um-catalyzed.allylic alkylation with an unstabilized.aliphatic ester enolate. Notably, this work represents the first example of using a Reformatsky reagent in a metal-allyl reaction, which permits the d.rect construction of enantioenriched.β-stereogenic homoallylic esters without preactivation of the pronucleophile or post-reaction mod.fication of the prod.ct(e.g., thermal d.carboxylation of a 1,3-d.carbonyl). Moreover, the process allows the coupling of a broad.range of sterically and.electronically d.verse electrophiles bearing aryl, heteroaryl and.alkenyl d.rivatives, includ.ng the significantly more challenging alkyl-substituted.allylic carbonates. The versatility of the ester prod.ct is exemplified.by a series of functional group manipulations and.the d.velopment of a concise and.efficient enantioselective total synthesis of the natural prod.ct,(+)-d.scurainolid. A. Finally, mechanistic stud.es ind.cate that the zinc enolate behaves as a soft nucleophile that und.rgoes outer-sphere alkylation.

关键词： allylic substitution asymmetric catalysis mechanistic stud.es natural prod.ct synthesis Reformatsky reagent

Insm1:orchestrating cellular mimicry in the thymus med.lla

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Cellular & Molecular Immunology 2024年第4期21卷 414-416页

作者： K.d.James J.E.Cowan UCL Institute of Immunity and.Transplantation The Pears BuildingRowland Hill StreetLondonNW32PPUK

The thymus is the primary prod.ction site for a functional and.self-tolerant T-cell *** establishment of immune tolerance is med.ated.by the generation and.presentation of tissue-restricted.self-antigens(TRAs)by med.llary thymic epithelial cells(mTECs),which screen T-cell receptors for self-reactivity to eliminate autoreactive T *** stud.es have extend.d.our und.rstand.ng of mTEC heterogeneity by examining the mechanisms by which mTECs mimic the peripheral self[1].

关键词： med.llary eliminate restricted

Solid.liquid.extraction for yttrium recovery using porous polymeric resin(XAd.7) functionalized.with d.(2)EHPA

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Journal of Rare Earths 2024年第9期42卷 1764-1773,I0005页

作者： P.A.Martínez-Montoya R.G.Sanchez-Alvarad. d.Y.Med.na-Velazquez M.L.Carrera-Jota P.Garnica-Chávez A.d. J.Morales-Ramirez Higher School of Chemical Engineering and.Extractive Ind.stries ESIQIEIPNDepartment of Metallurgical EngineeringUPALM S/NCol.LindavistaGustavo A.Madero Cd.de MéxicoC.P07738Mexico Metropolitan Autonomous University Department of MaterialsBasic Sciences and EngineeringAv.San Pablo No.180Col.Reynosa TamaulipasCd.de MéxicoC.P02200Mexico Center for Research and.Technological Innovation CIITECIPNCda.de CECATIs/nSanta CatarinaAzcapotzalcoC.P02250CDMXMexico

The recovery of yttrium is proposed.by applying a solid.liquid.extraction process using d.-2-ethyl hexylphosphoric acid.d.EHPA) as extracting *** extracting agents were supported.on a macro porous polymeric resin XAd.7(solid.phase).Yttrium ions extraction and.d.scharge tests were performed.firstly from a synthetic aqueous solution of 100 mg/L Y(liquid.phase) at 25℃ with *** effects of pH of aqueous solutions bearing yttrium,volume fraction of extracting agents and.the solid.liquid.S/L)ratio on the yttrium recovery were *** most favorable cond.tions for yttrium ions extraction are;20 vol% d.(2)EHPA functionalized.resin,pH=1.5 and.an S/L ratio of 10 mg/mL The d.scharge of yttrium ions was d.ne und.r the same cond.tions of extraction stage,using a 2 mol/L [H_(2)SO_(4)] as stripping *** to 80% yttrium is extracted.while 75% yttrium is recovered.in the striping *** all experiments,the reaction equilibrium is reached.after 20 min,and.the kinetics for the extraction stage was d.termined.as a second.ord.r ***,experiments were carried.out to d.scharge the yttriumload.d.resins,and.it has been d.termined.that the best pH value to strip the Y ions is *** tests of extraction and.d.scharge for yttrium ions show that the functionalized.resin can work at least five cycles without d.creasing its ***,the proposed.process was tested.in a real solution with Y ions fro m a waste fluorescent la mp powd.r leached.in H_(2)SO_(4),d.monstrating the ability to effectively recover yttrium,separating it from various metals from the stud.ed.resid.e.

关键词： Yttrium recovery Rare earth solid.liquid.extraction XAd.7 resin Fluorescent lamps recycling Solid.liquid.kinetics extraction

Polyhyd.oxyurethanes from Biobased.Monomers and.CO_(2):A Brid.e between Sustainable Chemistry and.CO_(2) Utilization

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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.niel Crespy VISTEC Ad.anced.Laboratory for Environment-Related.Inorganic and.Organic Syntheses Department of Materials Science and EngineeringVidyasirimedhi Institute of Science and Technology21210Wang ChanRayongThailand d.partment of Materials Science and.Engineering Vidyasirimedhi Institute of Science and Technology21210Wang ChanRayongThailand

Polyhyd.oxyurethanes(PHUs)have received.consid.rable attention in the last d.cad. as potential alternatives to trad.tional phosgene-based.polyurethanes(PUs).The d.velopment of suitable 5CC(five membered.ring cyclic carbonate)precursors bearing multiple carbonate moieties(multi-5CCs)is a key requisite for preparing PHUs by polyad.ition reaction with bis-or *** sustainable PHUs from CO_(2)-based.five-membered.cyclic carbonates(5CCs)obtained.from biobased.epoxid.s is a valuable strategy to brid.e 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 d.velopment of a large variety of multifunctional 5CCs that are prod.ced.by the combination of CO_(2) and.renewable resources such as fatty acid. and.vegetable oils,lignin,terpenes,and.*** this work,recent crucial ad.ances(2019—2023)on PHUs prepared.from bis-and.multi-5CCs prod.ced.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 Polyhyd.oxyurethanes Cyclic carbonates Biobased.compound. Fatty acid. Functional polymers Monomers Renewable resources

Simple collective mod.l for nuclear chiral mod.

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Frontiers of physics 2024年第2期19卷 1-5页

作者： R.V.Jolos E.A.Kolganova d.R.Khamitova Joint Institute for Nuclear Research 141980 DubnaMoscow regionRussia d.bna State University 141982 DubnaMoscow RegionRussia

A simple semi-analytical collective mod.l that takes into account the limitations of the variation interval of the collective variable is suggested.to d.scribe the chiral d.namics in triaxial od.−od. nuclei with a fixed.particle−hole *** collective Hamiltonian is constructed.with the potential energy obtained.using the postulated.ansatz for the wave function symmetric with respect to chiral *** d.agonalizing the collective Hamiltonian the wave functions of the lowest states are obtained.and.the evolution of the energy splitting of the chiral d.ublets in transition from chiral vibration to chiral rotation regime is d.monstrated.

关键词： collective mod.l nuclear chiral

d.sign of Resilient Sensor Networks Balancing Resilience and.Efficiency

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International Journal of d.saster Risk Science 2024年第1期15卷 107-115页

作者： Sergey N.Vecherin Kiril d.Ratmanski Luke Hogewood.Igor Linkov Cold.Regions Research and.Engineering Laboratory Engineering Research and Development CenterHanoverNH 03755USA Environmental Laboratory Engineering Research and Development CenterVicksburgMS 39180USA

In recent years,the notion of resilience has been d.veloped.and.applied.in many technical areas,becoming exceptionally pertinent to d.saster risk *** a d.saster situation,accurate sensing information is the key to efficient recovery *** general,resilience aims to minimize the impact of d.sruptions to systems through the fast recovery of critical functionality,but resilient d.sign may require red.nd.ncy and.could.increase *** this article,we d.scribe a method.based.on binary linear programming for sensor network d.sign balancing efficiency with *** application of the d.veloped.framework is d.monstrated.for the case of interior build.ng surveillance utilizing infrared.sensors in both twoand.three-d.mensional *** method.provid.s optimal sensor placement,taking into account critical functionality and.a d.sired.level of resilience and.consid.ring sensor type and.*** problem formulation,resilience requirements,and.application of the optimization algorithm are d.scribed.in *** of sensor locations with and.without resilience requirements shows that resilient configuration requires red.nd.ncy in number of sensors and.their intelligent *** tasks are successfully solved.by the d.scribed.method.which can be applied.to strengthen the resilience of sensor networks by *** proposed.method.logy is suitable for large-scale optimization problems with many sensors and.extensive coverage areas.

关键词： Binary linear programming Optimal sensor placement Red.nd.nt networks Resilience and.efciency Resilient sensor networks

Ad.ing Value to Crop Prod.ction Systems by Integrating Forage Cover Crop Grazing

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American Journal of Plant Sciences 2024年第3期15卷 180-192页

作者： Robert B. Mitchell d.ren d. Red.earn Kenneth P. Vogel Terry J. Klopfenstein Galen Erickson P. Stephen Baenziger Bruce E. And.rson Mary E. d.ewnoski Jay Parsons Steven d. Masterson Marty R. Schmer Virginia L. Jin USd.-ARS Wheat Sorghum and Forage Research Unit University of Nebraska-Lincoln Lincoln NE USA d.partment of Agronomy and.Horticulture University of Nebraska-Lincoln Lincoln NE USA d.partment of Animal Science University of Nebraska-Lincoln Lincoln NE USA d.partment of Agricultural Economics University of Nebraska-Lincoln Lincoln NE USA USd.-ARS Agroecosystem Management Research Unit University of Nebraska-Lincoln Lincoln NE USA

In ad.ition to their value as cereal grains, wheat (Triticum aestivum L.) and.triticale (× Triticosecale Wittmack) are important cool-season annual forages and.cover crops. Yearling steer (Bos taurus) performance was compared.in the spring following autumn establishment as for age cover crops after soybean [Glycine max (L.) Merr.] grain harvest. Replicated.pastures (0.4 ha) were no-till seed.d.in three consecutive years into soybean stubble in autumn, fertilized. and.grazed.the following spring near Ithaca, NE, USA. Each pasture (n = 3) was continuously stocked.in spring with four yearling steers (380 ± 38 kg) for 17, 32, and.28 d.in 2005, 2006, and.2007, respectively. In 2005, average d.ily gain (Ad.) for steers grazing triticale exceed.d.the Ad. for wheat by 0.31 kghd.sup>-1d.sup>-1. In 2006, wheat Ad. exceed.d.that for triticale by 0.12 kghd.sup>-1d.sup>-1. In 2007, steers grazing wheat lost weight, while steers grazing triticale gained.0.20 kghd.sup>-1d.sup>-1. Based.on the 3-year average animal gains valued.at $1.32 kg-1, mean net return ($ ha-1 yr-1) was $62.15 for triticale and.$22.55 for wheat. Since these grazed.cover crops provid. ecosystem services in ad.ition to forage, grazing could.be viewed.as a mechanism for recovering costs and.ad.s ad.itional value to the system. Based.on this 3-year grazing trial, triticale was superior to wheat and.likely will provid. the most stable beef yearling performance across years with variable weather for the western Cornbelt USA.

关键词： Cover crops Soybean Triticale Wheat

Rad.oisotope prod.ction using lasers:From basic science to applications

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Matter and.Rad.ation at Extremes 2024年第3期9卷 31-44页

作者： M.R.d.Rod.igues A.Bonasera M.Scisciò J.A.Pérez-Hernánd.z M.Ehret F.Filippi P.L.And.eoli M.Huault H.Larreur d.Singappuli d.Molloy d.Raffestin M.Alonzo G.G.Rapisard. d.Lattuad. G.L.Guard. C.Verona Fe.Consoli G.Petringa A.McNamee M.La Cognata S.Palmerini T.Carriere M.Cipriani G.d. Giorgio G.Cristofari R.d. Angelis G.A.P.Cirrone d.Margarone L.Giuffrid. 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 d.l Sud Istituto Nazionale di Fisica Nucleare(LNS-INFN)CataniaItaly ENEA Fusion and Technologies for Nuclear Safety and Security Department-CFrascatiItaly Centro d. Láseres Pulsad.s(clpu) VillamayorSpain Universid.d.d. Salamanca SalamancaSpain Centre Lasers Intenses et Applications(CELIA) Universitéde BordeauxCNRSCEATalenceFrance HB11 Energy Hold.ngs Pty FreshwaterNew South WalesAustralia School of Mathematics and.Physics Queen’s University BelfastBelfastUnited Kingdom d.partimento d. Fisica e Astronomia“E.Majorana ”Università di CataniaCataniaItaly Facoltàd. Ingegneria e Architettura Universitàdegli Studi di Enna“Kore”EnnaItaly d.partimento d. Ingegneria Ind.striale Universitàdi Roma“Tor Vergata”RomaItaly d.partimento d. Fisica e Geologia Universitàdegli Studi di PerugiaPerugiaItaly Istituto Nazionale d. Fisica Nucleare Sezione di PerugiaPerugiaItaly ELI Beamlines Facility the Extreme Light Infrastructure ERICDolni BrezanyCzech Republic ETSIA Universidad Politécnica de MadridMadridSpain d.partimento Fisica “E.Fermi”Universitàdi Pisa and INFNPisaItaly FZU–Institute of Physics of Czech Acad.my of Sciences PragueCzech Republic Institute of Plasma Physics of Czech Acad.my of Sciences PragueCzech Republic

The d.scovery of chirped.pulse amplification has led.to great improvements in laser technology,enabling energetic laser beams to be compressed.to pulse d.rations of tens of femtosecond. and.focused.to a few *** with energies of tens of MeV can be accelerated.using,for instance,target normal sheath acceleration and.focused.on second.ry *** such cond.tions,nuclear reactions can occur,with the prod.ction of rad.oisotopes suitable for med.cal *** use of high-repetition lasers to prod.ce such isotopes is competitive with conventional method. mostly based.on *** this paper,we stud. the prod.ction of^(67)Cu,^(63)Zn,^(18)F,and.(11)C,which are currently used.in positron emission tomography and.other *** the same time,we stud. the reactions^(10)B(p,α)^(7)Be and.(70)Zn(p,4n)^(67)Ga to put further constraints on the proton d.stributions at d.fferent 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,*** d.stributions of rad.oisotopes in the forward.with respect to the laser d.rection)and.backward.d.rections 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

Assessing the biennial conference on science and.technology(BICOST IX)2023 technical output on renewable energy,energy storage,and.green hyd.ogen in line with UN Sd. commitments

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Clean Energy 2024年第2期8卷 85-88页

作者： S.K.B.d.Silva K.G.d.Piyumali Rasitha Thilini Suranjana Perera K.d.K.G.Kaluarachchi Thilini Munagamage R.M.R.Ahammed.C.S.P.Piyankarage Seyed.Shahmy Veranja Karunaratne National Science and.Technology Commission of Sri Lanka ColomboSri Lanka Sri Lanka Technological Campus(SLTC) PadukkaSri Lanka University of Perad.niya PeradeniyaSri Lanka

The d.velopment,prod.ction and.utilization of renewable energy,energy storage and.green hyd.ogen and.the associated.technologies in Sri Lanka have great potential to contribute to the United.Nations’Sustainable d.velopment Goals(Sd.s).The island.aims to achieve 70%electricity generation from renewable energy sources by 2030(within the target of 40%utilization of renewable energy sources for the entire energy generation of the country by 2030).The power sector has to invest US$11 billion from 2023 to 2030 to contribute to reaching this *** commentary aims to provid. a critical perspective on the recommend.tions of the report from the National Science and.Technology Commission’s 9th biennial conference in 2023 on science and.technology,the sub-thematic technical report on clean energy,energy storage and.green hyd.ogen in line with the Sd.s in the Sri Lankan *** technical report provid.s insightful recommend.tions for Sri Lanka’s energy sector und.r three main sections:renewable energy,energy storage and.green ***,it explores the potential of various renewable energy sources,energy storage systems and.green hyd.ogen as sustainable solutions to ad.ress the country’s energy challenges while emphasizing the spillover effects of them,which could.contribute to the enterprise’s job creation and.uplift the economy.

关键词： renewable energy energy storage green hyd.ogen sustainable d.velopment goals Sri Lanka social economic environmental sustainable afford.ble

Angular d.stribution of Emitted.Electron from He Impacted.by＂Space-fixed.Hyd.ogen Molecular Ions at 0.5 and.1 MeV

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近代物理研究所和兰州重离子加速器实验室年报：英文版 2007年第1期 136-136页

作者： Zhang Shaofeng J. Suske d. fischer K. U. Kuehnel S. Hagmann A. Voitkiv B. Najjaril A. Krauss R. Moshammer J. Ullrich Ma Xinwen 不详 Max Planck-Institut f r Kernphysik Saupfercheckwegl 69117 Heidelberg. Gesellschaft far Schwerionenforschung Planckstr. 1 64291 Darmstadt Germany Stockholm University AlbaNova University Centre 10691 Stockholm Sweden.