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leading directions and effective distance of larch offspring dispersal at the upper treeline in the northern and Polar Urals, Russia

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Forest Ecosystems 2024年第5期11卷 603-617页

作者： P.A.Moiseev v.l.Semerikov T.v.Semerikova D.S.Balakin I.B.vorobiev S.O.viuykhin Institute of Plant and Animal Ecology Ural BranchRussian Academy of SciencesEkaterinburg620144Russia Center for Genetics and life Science Sirius University of Science and Technology354340SochiRussia

Climate has changed sufficiently over the last 150 years and forced out upper treeline advance at the most studied sites around the *** rate of advance has been extremely variable–from tens to hundreds meters in *** is because the degree at which tree frontal populations respond to climate change depends on the complex interaction of biological and physical *** resulting stand pattern is the consequence of the interaction between dispersal and survival functions.A few publications have addressed the question of how this pattern is *** order to understand how the spatial structure of tree stands was formed at the upper limit of their distribution in the Ural Mountains,we assessed the distance and direction of dispersal of offspring from maternal *** found that in frontal larix sibirica ***,‘effective’dispersal of offspring ranges from 3 to 758 m(with a median of 20–33 m in open forest and 219 m in single-tree tundra in the Polar Urals and 107 m in open forest in the northern Urals).We revealed that most of the offspring effectively dispersed not only in the direction of the prevailing winds,but also in the opposite direction up the slope,and the distance can reach 500–760 *** data obtained can be used to develop an individual-based model which is capable of simulating in detail the dynamics of tree stands at the upper limit of their growth and reliably predicting the future position and pattern of treeline ecotone as growth conditions continue to improve in the face of observed climate change.

关键词： Effective dispersal distance Upper treeline Parentage analysis Age estimation Terrestrial laser scanning larix sibirica Ural mountains

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Metal-modulated epitaxy of Mg-doped Al_(0.80)In_(0.20)n-based layer for application as the electron blocking layer in deep ultraviolet light-emitting diodes

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Journal of Semiconductors 2024年第5期45卷 80-89页

作者： horacio Irán Solís-Cisneros Carlos Alberto hernández-Gutiérrez Enrique Campos-González Máximo lópez-lópez Optomechatronics Group Tecnológico Nacional de México Campus Tuxtla Gutiérrezcarretera Panamericana 1080C.P.29050Tuxtla GutiérrezChiapasMéxico Departamento de Física Instituto Nacional de Investigaciones NuclearesCarretera México-Toluca s/nC.P.52750La Marquesa OcoyoacacMéxico Departamento de Física Centro de Investigación y estudios Avanzados del Instituto Politécnico NacionalAv.Instituto Politécnico Nacional 2508San Pedro ZacatencoGustavo A.Madero07360 Ciudad de MéxicoCDMXMéxico

This work reports the growth and characterization of p-AlInn layers doped with Mg by plasma-assisted molecular beam epitaxy(PAMBE).AlInn was grown with an Al molar fraction of 0.80 by metal-modulated epitaxy(MME)with a thickness of 180 nm on Si(111)substrates using Aln as buffer *** substrate temperatures were used to enhance the incorporation of indium atoms into the alloy without clustering,as confirmed by X-ray diffraction(XRD).Cathodoluminescence measurements revealed ultraviolet(Uv)range ***,hall effect measurements indicated a maximum hole mobility of 146 cm^(2)/(v∙s),corresponding to a free hole concentration of 1.23×10^(19)cm^(−3).The samples were analyzed by X-ray photoelectron spectroscopy(XPS)estimating the alloy composition and extracting the Fermi level by valence band ***-doped AlInn layers were studied for use as the electron-blocking layer(EBl)in lED *** varied the Al composition in the EBl from 0.84 to 0.96 molar fraction to assess its theoretical effects on electroluminescence,carrier concentration,and electric field,using SIlvACO *** results from this study highlight the importance and capability of producing high-quality Mg-doped p-AlInn layers through *** simulations suggest that an Al content of 0.86 is optimal for achieving desired outcomes in electroluminescence,carrier concentration,and electric field.

关键词： metal-modulated epitaxy AlInn DUv-lED EBl simulation

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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

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Discovery of new MAX-phase-like layered ternary carbide v_(8)P_(6)C:Crystal structure,thermal expansion,and elastic properties

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Journal of Materials Science & Technology 2024年第7期174卷 55-62页

作者： h.X.Chen l.Sheng Z.l.Zhang X.C.Wen D.l.Yang X.Y.Ye P.Q.Dai School of Materials Science and Engineering Fujian University of TechnologyFuzhou 350118China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of ScienceBeijing 100049China Fujian Provincial Key laboratory of Advanced Materials Processing and Application Fuzhou 350118China State Key laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Due to the laminated structure,MAX phases and MAX-phase-like compounds possess outstanding dam-age tolerance capability with good thermal/electrical conductivity and other charming functional prop-erties,showing a bright future for structural-functional ***,a new MAX-phase-like ternary car-bide v_(8)P_(6)C with layered characteristics was *** to the alternate stacking of hexagonal-arranged M/A/X atom layers in MAX phases,v_(8)P_(6)C has a layered structure formed by a repeated stacking of the slabs consisting of v_(6)C-octahedrons and vP 6-distorted-octahedrons in three-atomic layers *** thermal expansion anisotropy was revealed,with the thermal expansion coefficients(TECs)along a-axis,c-axis,and the average value,equal toα_(a)=8.55(5)μK^(−1),α_(c)=10.23(5)μK^(−1),andα_(l)=9.14(5)μK^(−1),*** dilation along the c-axis was mainly dominated by out-plane v-P bonds be-tween layered *** to the pressure-dependent lattice parameters,the polycrystalline bulk modulus(B_(0)=185(9)GPa)and high compressibility anisotropy factor(B_(a)/B_(c)=1.64)was ***-while,the second-order elastic constants were calculated,and the elastic moduli,E=303 GPa,B=198 GPa,G=122 GPa,andν=0.246,were *** the weak connection between layer slabs by out-plane v1-P bond was revealed by the bond stiffness model,with a bond stiffness close to the M-A bond in MAX ***,good damage tolerance capability was predicted according to Paugh’s ratio(G/B=0.616)and Cauchy pressure(P_(a)=0 GPa,P_(c)=-7.5 GPa),even better than those of typical MAX *** discovery of v_(8)P_(6)C provides a new member of MAX-phase-like damage-tolerant ceramic with relatively low density,moderate thermal expansion,and anisotropic compressibility,and the unique lay-ered structure is inspiring for exploring new layered ternary ceramics.

关键词： new ternary carbide MAX phase Thermal expansion Elastic constants Anisotropy

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B-l model with D_(4)×Z_(4)×Z_(2)symmetry for fermion mass hierarchies and mixings

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Chinese Physics C 2024年第6期48卷 11-30页

作者： v.v.vien Department of Physics Tay Nguyen UniversityDaklakVietnam

We constructed a gauge B-l model with D_(4)×Z_(4)×Z_(2)symmetry to explain the quark and lepton mass hierarchies and their mixings with realistic CP phases via the type-I seesaw *** quark mases,three quark mixing angles,and the CP phase in the quark sector take the central values whereas Yukawa couplings in the quark sector are diluted in a range of difference of three orders of magnitude by the perturbation theory at the first *** the neutrino sector,a small neutrino mass is achieved by the type-I seesaw *** inverted and normal neutrino mass hierarchies are consistent with the experimental *** predicted sum of neutrino masses for normal and inverted hierarchies,the effective neutrino masses,and the Dirac CP phase are also consistent with recently reported limits.

关键词： flavor symmetries quark and lepton masses and mixing extensions of electroweak gauge sector neutrino mass and mixing non-standard-model neutrinos right-handed neutrinos D4 discrete symmetry

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Global paleobiogeography of Albian—Cenomanian(mid-Cretaceous)marine ostracods

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Journal of Palaeogeography 2024年第2期13卷 212-236页

作者： Bernardo vázquez-García Jorge villegas-Martín Gerson Fauth leonardo Borghi Aristóteles De Moraes Rios netto Post-Graduate Program in Geology Unisinos UniversitySao LeopoldoRSBrazil Technological Institute of Paleoceanography and Climate Change-Itt Oceaneon Unisinos UniversitySao LeopoldoRSBrazil laboratory of Sedimentary Geology(lagesed) Department of GeologyInstitute of GeosciencesUFRJ-Federal Universityof Riode JaneiroBrazil labmicro Department of GeologyInstitute of GeosciencesUFRJ-Federal University of Rio de JaneiroBrazil

Despite their potential for providing important information for paleobiogeography,studies using ostracod assemblages compiled from global datasets have been scarce so *** this study,the paleogeographic implications of the relationship between different ostracod assemblages are analyzed and discussed for the Albian and *** compiled an ostracod dataset at the genus level,with 168 genera for the Albian and 174 for the Cenomanian,to which different multivariate statistical methods of grouping were *** affinity between different ostracod assemblages from different regions allowed for the delineation of 30 operational geographic units(OGUs)for the Albian,and 32 OGUs for the Cenomanian,grouped in three paleobiogeographic units(PBUs;Megatethys,Persia,and Austral)and one sub-unit(PBSU;Maghreb associated to the Megatethys).The Maghreb PBSU showed minor changes between the Albian and *** relationship among the OGUs grouped in each PBU is related to different factors,such as eustatic sea level events,similar climatic zones,and marine current circulation patterns.A relationship was observed between the Gabon and nigeria OGUs with the Persia PBU,which suggests a direct east—west connection between them during the *** affinity observed in the Austral PBU between the South American,South African,and Australian regions during the Albian can be explained by their relative geographic isolation due to the Walvis Ridge *** eventual flooding of this barrier led to the relationship observed between the SE Brazilian and Bolivian regions with the Austral ***,the data also suggested that the separation of the Indian subcontinent from the Austral PBU took place during the Cenomanian.

关键词： Operational geographic units Paleobiogeographic units Albian Cenomanian Marine ostracods

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Kinetics of dense plasma in the field of short laser pulses:A generalized approach

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Matter and Radiation at Extremes 2024年第5期9卷 87-92页

作者： v.A.Astapenko v.S.lisitsa Moscow Institute of Physics and Technology(national Research University) Institutskii per.9141701 DolgoprudnyiRussia national Research Centre“Kurchatov Institute ”123182 MoscowRussia national Research nuclear University MEPhI 115409 MoscowRussia

A generalized kinetic model of atomic level populations in an optically dense plasma excited by laser pulses of arbitrary duration is formulated and *** model is based on a nonstationary expression for the probability of excitation of an atomic transition and takes into account the effects of laser pulse penetration into an optically dense medium.A universal formula for the excitation probability as a function of time and propagation length is derived and applied to the case of a lorentzian spectral profile of an atomic transition excited by a laser pulse with a Gaussian *** features of nonstationary excitation probabilities are presented for different optical depths of the plasma,laser pulse durations,and carrier *** formulas derived here will be useful for the description of atomic populations excited by laser pulses under realistic conditions of dense plasmas.

关键词： laser excitation excited

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Telluric iron assemblages as a source of prebiotic phosphorus on the early Earth:Insights from Disko Island,Greenland

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Geoscience Frontiers 2024年第5期15卷 415-429页

作者： Oleg S.vereshchagin Maya O.Khmelnitskaya larisa v.Kamaeva natalia S.vlasenko Dmitrii v.Pankin vladimir n.Bocharova Sergey n.Britvin Saint Petersburg State University University Embankment 7-9St.Petersburg 199034Russia Udmurt Federal Research Center Ural BranchRussian Academy of SciencesIzhevsk 426067Russia nanomaterial Research Center Kola Science CentreRussian Academy of SciencesApatity 184209Russia

Phosphorus is one of the key elements,which determined the emergence of primordial life on our *** source of prebiotic phosphorus was most likely to be easily soluble compounds containing phosphorus in the negative form of oxidation(e.g.,phosphides).The present paper is the first thorough investigation of phosphide-bearing mineral assemblages confined to telluric(terrestrial)native iron from volcanic rocks of Disko Island,*** speciation in given assemblages varies from the solid solution in native iron(up to 0.3 wt.%P),different phosphides–schreibersite Fe_(3)P,nickelphosphide ni_(3)P,barringerite Fe_(2)P,and phosphates,including fluorapatite,anhydrous Fe-na phosphates,phosphoran olivine and pyroxene(up to 1 wt.%P).The diversity of observed phosphorus speciation can be explained by the steep changes of redox conditions during subsurface crystallization of iron-phosphide-bearing *** on the available data on likely redox conditions on the early Earth,we hypothesize that reactive prebiotic phosphorus may have originated from shallow crustal rocks.

关键词： Prebiotic phosphorus native iron Phosphide Reduced mineral assemblages

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Rational design of AgGaS/ZnS/ZnS quantum dots with a near-unity photoluminescence quantum yield via double shelling scheme

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Journal of Materials Science & Technology 2024年第2期169卷 235-242页

作者： h.X.lu h.liu Z.Z.Fu Y.Y.Chen h.Q.Dai Z.hu W.l.Zhang R.Q.Guo Institute for Electric light Sources School of Information Science and TechnologyFudan UniversityShanghai 200433China Institute of Future lighting Academy for Engineering and TechnologyFudan UniversityShanghai 200433China Yiwu Research Institute of Fudan University YiwuZhejiang 322000China Zhongshan-Fudan Joint Innovation Center Zhongshan 528437China

In this study,a two-step method was used to synthesize highly luminescent AgGaS/ZnS/ZnS quantum dots(QDs).In the first step,an inner ZnS shell was formed via a one-pot method,which resulted in a smaller lattice mismatch between the AgGaS core and the outer ZnS shell,thereby facilitating the formation of a thick outer *** the two-step shelling process,the synthesized AgGaS/ZnS/ZnS QDs showed an excellent photoluminescence quantum yield(PlQY)of 96.4%with a peak wavelength of 508 nm,repre-senting the highest PlQY reported thus far for AgGaS ***,the effect of halogen ions in Zn precursors on the shelling process was *** was proposed that the capacity of halogen ions to coordinate with the QDs influenced the balance between Zn cation diffusion and ZnS shelling ***,the ZnS shelling reaction was dominant when ZnCl_(2)was employed,while Zn cation diffusion was the dominant process under the I^(−)-rich *** work provides insights into the interfacial restructuring during the ZnS shelling and offers a clear map for the tailored synthesis of core/shell QDs.

关键词： AgGaS Quantum dots Photoluminescence Core/shell Alloyed core/shell interface

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Advanced Oxidation Wastewater Treatment of 3 lPS of an Avocado Sauce Company,at Morelia,Michoacan,Mexico

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Journal of Environmental Science and Engineering(A) 2024年第5期13卷 151-155页

作者： Alfonso Espitia-Cabrera Francisco Javier Barrón-Santos Josél.Méndez-Antonio héctor M.Alemán-vásquez Omar G.Color-vázquez Saneamiento y Planeación Ambiental Azcapotzalco CDMX 02200México Energy Department Metropolitan Autonomous University Azcapotzalco CampusCDMX 02200Mexico Environmental System Engineering Department Environmental Engineering AcademyNational School of Biological SciencesNational Polytechnic InstituteCiudad de MéxicoCDMX 07738México Planta Congeladora y Empacadora nacional Morelia 58190MichoacánMéxico

This paper describes the wastewater treatment of 3 liters per second of capacity of discharges of capacity,from the avocado washed,as well as the production of avocado *** were pretreated with a grease and oil trap and contained small amounts of oil and grease,dissolved and total solids,organic matter and trace of organic and inorganic compounds from the vitamins and minerals of *** treatment train is located in an small surface and the train is integrated with coagulation in line with alumina in a static mixer,rapid filtration in two steps,double advanced oxidation with ozone and heterocyclic photocatalysis with a nanofilm of zinc oxide as,photocatalyzer and final adsorption of refractory compounds with activated *** treated wastewater meets the environmental regulation to urban sewerage discharges of the city,according to the results of a Mexican Certified laboratory.

关键词： Wastewater primary treatment rapid filter performance static mixer

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