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Highly divergent sympatric lineages of Leptotila verreauxi(Aves:Columbidae)suggest a secondary contact area in the isthmus of Tehuantepec,Mexico

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Avian Research 2024年第1期15卷 12-21页

作者： Orlando j.Espinosa-chávez Adolfo G.Navarro-Sigüenza Hernando Rodríguez-Correa Luis A.Sánchez-González Museo de Zoología“Alfonso L.Herrera” Depto.de Biología EvolutivaFacultad de CienciasUniversidad Nacional Autonoma de MexicoApdo.Postal 70-399CP 04510Ciudad de MexicoMexico Posgrado en Ciencias Biologicas Unidad de PosgradoEdificio D1◦PisoCircuito de PosgradosCiudad UniversitariaUniversidad Nacional Autonoma de MexicoCoyoacanCP 04510CDMXMexico Escuela Nacional de Estudios Superiores Unidad Morelia Universidad Nacional Autonoma de Mexico.Antigua Carretera a Patzcuaro No.8701 Col.Ex Hacienda de San Jose de la HuertaC.P.58190MoreliaMichoacanMexico

Due to a complex geological and biotic history,the isthmus of Tehuantepec(iT),has been long recognized as a driver for the evolutionary divergence of numerous lowland and highland *** distributed in the lowlands of the American continent,the White-Tipped Dove(Leptotila verreauxi)is a polytypic species with 13 recognized *** of these have been recorded in Mexico,and the distribution of three abuts at the iT,suggesting a contact *** estimate phylogenetic patterns,divergence times and genetic differentiation,we examined two mt DNA(ND2 and COi)and one n DNA(β-fibint 7)*** also used correlative ecological niche models(ENM)to assess whether ecological differences across the iT may have acted as a biogeographical *** estimated paleodistributions during the Middle Holocene,Last Glacial Maximum and Last interglacial,to evaluate the influence of climate changes on the distribution and demographic *** results showed genetically distinct lineages that diverged approximately 2.5 million years *** and ecological factors may have played a dual role in promoting differentiation,but also in the formation of a secondary contact zone in the southern *** ecological niche comparisons indicated that the ecological niche of sympatric lineages at the iT are not identical,suggesting niches divergence;in addition,environmental niche models across the region indicated no abrupt biogeographic barriers,but the presence of regions with low *** results suggest that genetic differentiation originated by a vicariant event probably related to environmental factors,favored the evolution of different ecological ***,the absence of a biogeographic barrier but the presence of less suitable areas in the contact regions,suggest that secondary contact zones may be also maintained by climatic factors for the eastern group,but also by biotic interactions for the western group.

关键词： Biogeographical boundary Humid and dry forests isthmus of Tehuantepec Phylogeography Secondary contact

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-Alvarado D.Y.Medina-Velazquez M.L.Carrera-jota P.Garnica-chávez A.de j.Morales-Ramirez Higher School of chemical Engineering and Extractive industries 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 di-2-ethyl hexylphosphoric acid(D2EHPA) as extracting *** extracting agents were supported on a macro porous polymeric resin XAD-7(solid phase).Yttrium ions extraction and discharge 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 conditions 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 discharge of yttrium ions was done under the same conditions 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 determined as a second-order ***,experiments were carried out to discharge the yttriumloaded resins,and it has been determined that the best pH value to strip the Y ions is *** tests of extraction and discharge for yttrium ions show that the functionalized resin can work at least five cycles without decreasing its ***,the proposed process was tested in a real solution with Y ions fro m a waste fluorescent la mp powder leached in H_(2)SO_(4),demonstrating the ability to effectively recover yttrium,separating it from various metals from the studied residue.

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

Wettability,reactivity,and interface structure in Mg/Ni system

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journal of Magnesium and Alloys 2024年第2期12卷 659-672页

作者： S.Terlicka N.Sobczak Ł.Maj P.Darłak j.j.Sobczak institute of Metallurgy and Materials Science Polish Academy of Sciences25 Reymonta Str.KrakowPoland Faculty of Foundry Engineering AGH University23 Reymonta Str.KrakowPoland

The sessile drop method was applied to the experimental investigation of the wetting and spreading behaviors of liquid Mg drops on pure Ni *** comparison,the experiments were performed in two variants:(1)using the Capillary Purification(CP)procedure,which allows the non-contact heating and squeezing of a pure oxide-free Mg drop;(2)by classical Contact Heating(ch)*** high-temperature tests were performed under isothermal conditions(CP:760℃for 30 s;ch:715℃for 300 s)using Ar+5 wt%H_(2) *** the sessile drop tests,images of the Mg/Ni couples were recorded by CCD cameras(57 fps),which were then applied to calculate the contact angles of metal/substrate *** and transmission electron microscopy analyses,both coupled with energy-dispersive X-ray spectroscopy,were used for detailed structural characterization of the solidified *** was found that an oxide-free Mg drop obtained by the CP procedure showed a wetting phenomenon on the Ni substrate(an average contact angleθining and good wetting over the Ni substrate(θ_((CP))~20°in 5 s)to form a final contact angle ofθ_(f(CP))~18°.in contrast,a different wetting behavior was observed for the ch procedure,where the unavoidable primary oxide film on the Mg surface blocked the spreading of liquid Mg showing apparently non-wetting behavior after 300 s contact at the test ***,in both cases,the deep craters formed in the Ni substrates under the Mg drops and significant change in the structure of initially pure Mg drops to Mg-Ni alloys suggest a strong dissolution of Ni in liquid Mg and apparent values of the final contact angles measured for the Mg/Ni system.

关键词： Magnesium-based alloys Sessile drop tests Capillary purification procedure Wettability Reactivity Contact angle

Geochemical studies of hybrid granite from Madugulapalli area, Eastern Dharwar Craton, Southern india: implications for crustal mixing

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Acta Geochimica 2023年第1期42卷 9-23页

作者： Nagamma j Ratnakar j Ajay kumar A Ashok ch State Mines and Geology Department 508001 NalgondaIndia Department of Geology Osmania University500007 HyderabadIndia CSiR-National Geophysical Research institute 500007 UppalHyderabadIndia

Magma produced by melting of continental crust and mantle at the Archean-Proterozoic boundary are compositionally variable and chemical compositions provide evidence for the mixing of two sources. Understanding the composition of hybrid magma is essential for determining the comparative infl uence of crust and mantle sources during orogenesis. The hybrid granites are less documented in indian cratons, especially less in Dharwar Craton. Here we present petrographic and whole-rock geochemical data of Madgulapalli granitic rocks situated in the NE part of the Eastern Dharwar Craton(EDC), to elucidate their petrogenesis and role in crust formation. The Madugulapalli granites(MPG) are composed chiefl y of plagioclase, quartz, and alkali feldspar with associated biotite showing alteration and inter-granular textures. Geochemically, they are metaluminous to peraluminous in nature with calc-alkaline hybrid granite. The hybrid granites exhibit both negative and positive europium anomalies;the lower Rb/Sr, Rb, Sr, and higher Sr/Y,(Dy/Yb)N ratios suggest that the interaction of older rocks with residual garnet source melted at high pressures. We hypothesize that hybrid granites are formed by interaction(e.g., metasomatism, mingling, or mixing) between parental magmas and pre-existing rocks with the infl uence of sanukitoid melts(heat source) in a subduction environment. The genesis of the hybrid granites demonstrates the mixing coupled with diff erentiation in the petrogeny’s residue system in a syn-collision setting followed by continental crust stability in EDC during the Neoarchean period.

关键词： Madugulapalli granite Hybrid granite Crustal mixing Subduction

Further investigation on the fusion of ^(6)Li with ^(209)Bi target at near-barrier energies

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chinese Physics C 2024年第7期48卷 106-117页

作者：张高龙焦振威张广鑫 M.R.Cortes 胡世鹏钱建强 D.Mengoni 屈卫卫李聪博郑云张焕乔孙慧斌王楠张春雷 j.j.Valiente-Dobón D.Testov M.Mazzocco A.Gozzelino C.Parascandolo D.Pierroutsakou M.La Commara A.Goasduff D.Bazzacco D.R.Napoli F.Galtarossa F.Recchia A.illana S.Bakes i.Zanon S.Aydin G.de Angelis M.Siciliano R.Menegazzo S.M.Lenzi j.L.Ferreira j.Rangel Serkan Akkoyun L.F.Canto j.Lubian School of Physics Beihang UniversityBeijing 100191China Sino-French institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China instituto de Física Universidade Federal Fluminense24210-340NiteróiRio de JaneiroBrazil institute for Advanced Study in Nuclear Energy&Safety Shenzhen UniversityShenzhen 518060China Shenzhen Key Laboratory of Research and Manufacture of High Purity Germanium Materials and Fetectors Shenzhen UniversityShenzhen 518060China iNFN Sezione di PadovaPadovaItaly Dipartimento di fisica Astronomia dell'Universita di padova PadovaItaly State Key Laboratory of Radiation Medicine and Protection School of Radiation Medicine and ProtectionSoochow UniversitySuzhou 215123China china institute of Atomic Energy Beijing 102413China The Key Laboratory of Beam Technology and Material Modification of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China iNFN Laboratori Nazionali di LegnaroI-35020 LegnaroItaly iNFN Sezione di NapoliI-80126 NapoliItaly Dipartimento di Farmacia Universitàdi Napoli"Federico II"I-80131 NapoliItaly Department of Natural and Mathematical Sciences Faculty of EngineeringTarsus University33480 MersinTurkiye Physics Division Argonne National LaboratoryLemont-ILUSA Departamento de Matemaética Física e Computaç˜ao Universidade do Estado do Rio de JaneiroFaculdade de Tecnologia27537-000ResendeRio de JaneiroBrazil Department of Physics Sivas Cumhuriyet UniversitySivasTurkey instituto de Física Universidade Federal do Rio de JaneiroCP 6852821941-972Rio de JaneiroBrazil

The complete and incomplete fusion cross sections for ^(6)Li+^(209)Bi were measured using the in-beamγ-ray method around the Coulomb *** cross sections of(deuteron captured)incomplete fusion(iCF)products were re-quantified experimentally for this reaction *** results reveal that the iCF cross section is equivalent to that of complete fusion(CF)above the Coulomb barrier and dominant near or below the Coulomb barrier.A theoretical calculation based on the continuum discretized coupled channel(CDCC)method was performed for the aforementioned CF and iCF cross sections;the result is consistent with the *** universal fusion function(UFF)was also compared with the measured CF cross section for different barrier parameters,demonstrating that the CF suppression factor is significantly influenced by the choice of potential,which can reflect both dynamic and static effects of breakup on the fusion process.

关键词： cross section incomplete fusion suppression factor weakly bound nuclei

Universal insertion of molecules in ionic compounds under pressure

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National Science Review 2024年第1期11卷 120-128页

作者： Feng Peng Yanming Ma chris j.Pickard Hanyu Liu Maosheng Miao College of Physics and Electronic information Luoyang Normal University Department of chemistry and Biochemistry California State University Northridge State Key Laboratory of Superhard Materials & Key Laboratory of Material Simulation Methods and Software of Ministry of Education College of Physics Jilin University international Center of Future Science Jilin University Department of Materials Science & Metallurgy University of Cambridge Advanced institute for Materials Research Tohoku University Department of Earth Science University of California Santa Barbara

Using first-principles calculations and crystal structure search methods, we found that many covalently bonded molecules such as H2, N2, CO2, NH3, H2O and ch4may react with NaC l, a prototype ionic solid,and form stable compounds under pressure while retaining their molecular structure. These molecules,despite whether they are homonuclear or heteronuclear, polar or non-polar, small or large, do not show strong chemical interactions with surrounding Na and Cl ions. in contrast, the most stable molecule among all examples, N2, is found to transform into cyclo-N5-anions while reacting with NaC l under high pressures. it provides a new route to synthesize pentazolates, which are promising green energy materials with high energy density. Our work demonstrates a unique and universal hybridization propensity of covalently bonded molecules and solid compounds under pressure. This surprising miscibility suggests possible mixing regions between the molecular and rock layers in the interiors of large planets.

关键词： molecule-solid hybrid materials high-pressure crystal structure prediction density functional theory planet interior

A NOVEL THEORY OF EFFECTiVE MEchANiCAL PROPERTiES OF CLOSED-CELL FOAM MATERiALS

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Acta Mechanica Solida Sinica 2013年第6期26卷 559-569页

作者： Yuli Ma Xianyue Su R.Pyrz j.ch.Rauhe The State Key Laboratory for Turbulence and Complex Systems (LTCS) and Department of Mechanics and Aerospace Engineering College of EngineeringPeking University chinalco Research institute of Science and Technology Department of Mechanical and Manufacturing Engineering Aalborg University

in this paper a new theory of effective mechanical properties of foam materials is proposed. A cell volume distribution coefficient is introduced to modify the original Gibson-Ashby equations of effective mechanical properties of foam materials. The constants that influence the effective modulus are replaced by the coeff^cient. Based on the modified distribution coefficient, the yield stress is also recalculated. Using X-ray microtomography, the internal structures of dif- ferent samples of polypropylene-nanoclay foam are obtained. The cell volume distributions of these samples are derived from the experiment by image analysis and the fitting curves are plot- ted. The distribution coefficient is acquired using the parameters from the theoretical model of the distribution curves. The results of the improved theory are compared with the experimental values and show good fitting quality. it was found that the precision of the improved theory is high and the cell volume distribution has an impact on the effective mechanical properties that would lead to the optimization of the synthesis procedure.

关键词： closed-cell foam cell volume distribution distribution coefficient Young's modulus yield stress distribution function

Effects of different organic fertilizers on nitrous oxide and methane emissions from double-cropping rice fields

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Pedosphere 2024年第1期34卷 52-62页

作者： Mingcheng HU Andrew j.WADE Weishou SHEN Zhenfang ZHONG chongwen QiU Xiangui LiN jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science&TechnologyNanjing 210044China Department of Geography and Environmental Science University of ReadingReading RG66 DWUK Haina Research institute of Guangdong Haina Agricultural Co. Ltd.Huizhou 516000China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China

Rice fields are a major source of greenhouse gases,such as nitrous oxide (N_(2)O) and methane (ch_(4)).Organic fertilizers may potentially replace inorganic fertilizers to meet the nitrogen requirement for rice growth;however,the simultaneous effects of organic fertilizers on N_(2)O and ch_(4)emissions and crop yield in paddy fields remain poorly understood and *** this study,experimental plots were established in conventional double-cropping paddy fields in the Pearl River Delta,china,including an unfertilized control and five fertilizer treatments with fresh organic fertilizer (FOF),successively composted organic fertilizer (SOF),chemically composted organic fertilizer (COF),COF supplemented with inorganic fertilizer (COiF),and chemical fertilizers (CFs)(TFOF,TSOF,TCOF,TCOiF,and TCF,respectively).Paddy field soils behaved simultaneously as an N_(2)O sink (cumulative N_(2)O emission:-196 to-381 g N ha^(-1)) and as a ch_(4)source (cumulative ch_(4)emission:719 to 2 178 kg ha^(-1)).Compared to CFs,the effects of organic fertilizers on N_(2)O emission were not *** contrast,total annual ch_(4)emission increased by 157%,132%,125%,and 37%in TFOF,TCOF,TSOF,and TCOiF,respectively,compared to *** TCOiF,rice yield was maintained,while ch_(4)emission was not significantly increased from the paddy fields characterized by a prolonged flood *** important next step is to extend these field-based measurements to larger rice cultivation areas to quantify the regional and national-scale impacts on greenhouse gas emissions and to help determine the optimum practice for fertilizer use.

关键词： crop production global warming potential greenhouse gases manure paddy sustainable agriculture

One-neutron stripping process in the^(209)Bi(^(6)Li,^(5)Li)^(210)Bi*reaction reaction

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Nuclear Science and Techniques 2024年第6期35卷 120-129页

作者： Gao-Long Zhang Zhen-Wei jiao Guang-Xin Zhang E.N.Cardozo B.Paes Shi-Peng Hu jian-Qiang Qian Daniele Mengoni Wei-Wei Qu Cong-Bo Li Yun Zheng Huan-Qiao Zhang Hui-Bin Sun Nan Wang chun-Lei Zhang j.j.Valiente-Dobón D.Testov M.Mazzocco A.Gozzelino C.Parascandolo D.Pierroutsakou M.La Commara A.Goasduff D.Bazzacco D.R.Napoli F.Galtarossa F.Recchia A.illana S.Bakes i.Zanon S.Aydin Gde Angelis M.Siciliano R.Menegazzo S.M.Lenzi S.Akkoyun L.F.Canto j.Lubian School of Physics Beihang UniversityBeijing 100191China Sino-French institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China instituto de Física Universidade Federal Fluminense24210-340 NiteróiRio de JaneiroBrazil Laboratorio TANDAR Comisión Nacional de Energía AtómicaBKNA1650 San MartíınArgentina institute for Advanced Study in Nuclear Energy and Safety Shenzhen UniversityShenzhen 518060China Shenzhen Key Laboratory of Research and Manufacture of High Purity Germanium Materials and Fetectors Shenzhen UniversityShenzhen 518060China iNFN Sezione di PadovaPaduaItaly Dipartimento di fisica Astronomia dell’Universita di padova PaduaItaly State Key Laboratory of Radiation Medicine and Protection School of Radiation Medicine and ProtectionSoochow UniversitySuzhou 215123China china institute of Atomic Energy Beijing 102413China The Key Laboratory of Beam Technology and Material Modification of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Laboratori Nazionali di Legnaro INFN35020 LegnaroItaly iNFN Sezione di Napoli80126 NaplesItaly Dipartimento di Farmacia Universitàdi Napoli“Federico II”80131 NaplesItaly Department of Natural and Mathematical Sciences Faculty of EngineeringTarsus University33480 MersinTurkey Physics Division Argonne National LaboratoryLemontILUSA Department of Physics Sivas Cumhuriyet UniversitySivasTurkey instituto de Física Universidade Federal do Rio de JaneiroRio de Janeiro CP 6852821941-972Brazil

One-neutron stripping process between^(6)Li and^(209)Bi was studied at 28,30,and 34 MeV using the in-beamγ-ray spectroscopy ***γ-γcoincident analysis clearly identified twoγ-rays feeding the ground and long-lived isomeric states,which were employed to determine the cross *** one-neutron stripping cross sections were similar to the cross sections of complete fusion in the^(6)Li+^(209)Bi system,but the one-neutron stripping cross sections decreased more gradually at the sub-barrier region.A coupled-reaction-channel calculation was performed to study the detailed reaction mechanism of the one-neutron stripping process in^(6)*** calculations indicated that the first excited state of 5 Li is critical in the actual one-neutron transfer mechanism,and the valence proton of 209Bi can be excited to the low-lying excited state in(^(6)Li,^(5)Li)reaction,unlike in the(d,p)reaction.

关键词： Transfer reaction Weakly bound nuclei Cross section