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integrative Zoology 2024年第3期19卷 458-467页

作者： Roman sHARNUUD Eric i.AMECA MOE Key Laboratory for Biodiversity science&Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijingChina Climate Change specialist Group Species Survival CommissionInternational Union for Conservation of NatureGlandSwitzerland

A significant research focus is placed on identifying animal species and areas at future risk to human-induced alterations of the environment and long-term changes in climatic ***,the extent to which exposure to extreme climatic events and intense human pressure can increase the risk of harmful impacts on species remains poorly *** on terrestrial mammals in China,one of the world’s megadiverse countries,we investigated patterns of contemporary exposure to floods and human pressures and determined their taxonomic representation and distribution across three major area-based conservation schemes,namely,national nature reserves(NNRs),priority areas for biodiversity conservation(PABCs),and key biodiversity areas(KBAs).Among the 440 species assessed with moderate or high exposure to floods,327(∼75%)also qualified as moderate or high in exposure to intense human *** species mainly belong to the orders Chiroptera,Eulipotyphla,and ***,there were 305,311,and 311 species with moderate or high exposure to flood and intense human pressure represented across NNRs,PABCs,and KBAs,*** findings support the prioritization of KBAs for expansion of site-based protection efforts such as NNRs in China,considering threats to species from exposure to adverse effects from both extreme climate and human pressure.

关键词： conservation floods human pressure mammals taxonomy

Microstructure， electrochemical， wear and corrosive wear performance of laser-based powder bed fusion(lpbf) and wrought biomedical Ti-6Al-4V alloys

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Transactions of Nonferrous Metals society of China 2024年

作者： A.G.Lekatou B.V.Efremenko V.Haoui V.G.Efremenko s.Emmanouilidou V.i.Zurnadzhy i.Petryshynets Yu.G.Chabak i.i.sili Laboratory of Applied Metallurgy， Department of Materials science and Engineering， school of Engineering， University of ioannina institute of Materials science and Computing， University Research Center of ioannina (URCi) Pryazovskyi state Technical University， Department of Physics institute of Materials Research of slovak Academy of sciences

Wrought and laser powder bed fusion （LPBF） Ti-6Al-4V specimens were comparatively evaluated， with the objective to determine LPBF Ti-6-4’s suitability for biomedical applications. Testing included nanoindentation， cyclic polarization in simulated body fluid （sBF， 37 ℃ ）， and dry and sBF “Ball-on-Plate” sliding. Wrought Ti-6-4 exhibited a lamellar （α+β） microstructure， whereas LPBF displayed a fine-grained α'-martensite microstructure. LPBF Ti-6-4 demonstrated ～3% higher indentation modulus and ～32% higher hardness， while wrought Ti-6-4 showed ～8% higher plasticity. Both alloys exhibited low corrosion rates (10–5mA/cm2order) and true passivity (10–4mA/cm2order). No localized corrosion was observed in either alloy， except for occasional metastable pitting in the LPBF alloy. However， LPBF Ti-6-4 presented higher corrosion rate and passive current， ascribed to its martensitic structure. During dry sliding， LPBF Ti-6-4 exhibited ～14% lower volume loss compared to wrought Ti-6-4. sliding in sBF increased volume losses for both alloys， with wear resistances nearly equalized， as the advantage of LPBF Ti-6-4 decreased due to more intensive wear-accelerated corrosion induced by the stressed martensite. Overall， the results demonstrate the suitability of LPBF Ti-6Al-4V for biomedical uses.

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Rare earth based MgPm_(2)X_(4)(X=s,se) spinel chalcogenides for spintronic and thermoelectric applications

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Journal of Rare Earths 2024年第8期42卷 1577-1585,I0006页

作者： Tariq M.Al-Daraghmeh Omar Zayed Ghulam M.Mustafa Taharh Zelai Bisma Younas Hind Albalawi s.Bouzgarrou Othman Hakami Q.Mahmood Khaild i.Hussein Basic sciences Department King Abdullah Ⅱ School of EngineeringPrincess Sumaya University For TechnologyP.O.Box 1438Al-jubaiha11941AmmanJordan Department of Physics Division of Science&TechnologyUniversity of EducationLahorePakistan Department of Physics Faculty of ScienceJazan University JazanSaudi Arabia Department of Physics The University of LahoreLahorePakistan Department of Physics College of SciencesPrincess Nourah bint Abdulrahman University(PNU)P.O.Box 84428Riyadh11671Saudi Arabia Department of Physics College of ScienceQassim UniversityPo.64BuraidahSaudi Arabia Laboratoire de Microelectronique et instrumentation(UR 03/13-04) Faculte des Sciences de MonastirAvenue de I'Environnement 5000MonastirTunisia Department of Chemistry Faculty of ScienceJazan University JazanSaudi Arabia Basic&Applied scientific Research Center Department of PhysicsCollege of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam 31441Saudi Arabia Department of Radiological sciences College of Applied Medical SciencesKing Khalid UniversityAbha61421Saudi Arabia

in current report,the structural,magnetic,and thermoelectric properties of RE doped MgPm_(2)X_(4)(X=s,se) spinels were *** energy difference in ferromagnetic and antiferromagnetic states reveals the stability of MgPm_(2)(s/se)_(4) in the ferromagnetic *** co mputation of enthalpy of formation also ascertains thermodynamic stability of crystal ***-dependent band structure and density of states analysis reveal ferromagnetic semiconducting character showing different electronic behavior in both spin *** room temperature ferromagnetism,spin polarization and Curie temperature are estimated from exchange energies *** addition,exchange constants(N_(0)α and N_(0)β),exchange energy Δ_(x)(pd),crystal ifeld energy,and double exchange mechanism were studied to explore the magnetic ***,the electrical conductivity,thermal conductivity,seebeck co-efficient,and power factor show effect on electrons spin and their potential for thermoelectric devices.

关键词： Rare earth elements spintronic applications Thermoelectric effects Exchange energies

Old-growth mixed dipterocarp forests show variable losses and gains in aboveground biomass and standing carbon over forty years

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Forest Ecosystems 2024年第1期11卷 14-23页

作者： sisira Ediriweera Champika Bandara Tithira Lakkana shanika Jayasinghe David Woodbury Arun Dayanandan B.M.P.singhakumara Xiangcheng Mi i.A.U.N.Gunatilleke C.V.s.Gunatilleke Mark sAshton Department of science and Technology Uva Wellassa UniversityBadullaSri Lanka The Forest school Yale School of the EnvironmentYale UniversityNew HavenCT06511USA Department of Forestry and Environmental science University of Sri JayewardenepuraNugegodaSri Lanka state Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing100093China Botany Department University of PeradeniyaPeradeniyaSri Lanka

Background:No studies have documented long-term trends in aboveground biomass(AGB)for mixed-dipterocarp forests(MDF),the dominant rain forest type in tropical wet equatorial *** our study,we sought to document such trends over forty years across three sites representing lowland to lower montane ***:To do this,we established fifty 100 m×25 m plots in 1978 across three sites sampled along an elevation gradient,identified as mature old-growth *** measured trees for diameter at breast height that we identified to species and *** took wood samples to calculate species wood-specific *** re-measured plots in 1998 and again in ***:We show standing AGB for all sites combined to be 517.52 Mg·ha^(-1)in 1978,but this declined by 17%over 40 years to 430.11 Mg·ha^(-1).No differences exist among sites in AGB primarily because of considerable within site variation;but interactions of time with site show declines across sites were not uniform,one remained about the *** few species represented a high proportion of the AGB with the top five species comprising between 34%and 65%,depending upon site and year *** species,Mesua nagassarium,represented a disproportionately large amount of AGB and decline over time,particularly at the low elevation ***:Our results are directly relevant to estimating AGB and standing carbon sequestered in *** study is the first to demonstrate varying but overall,declining trends in amounts of AGB among forests making predictions of biomass and standing carbon in MDF difficult over wide regions.

关键词： Western ghats shorea spp. southeast Asia sri Lanka Tropical rain forest Wood specific gravity

Change in Grain-size Composition of Lignite under Cyclic Freezing-Thawing and Wetting-Drying

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Natural Resources 2024年第1期15卷 17-27页

作者： Natalia s. Batugina Vladislav i. Fedorov Chersky institute of Mining of the North siberian Branch Russian Academy of sciences Yakutsk Russia

The paper presents the change in grain-size composition of lignite under cyclic freezing-thawing (FTC) and wetting-drying (WDC). The article shows that in the spring and autumn periods the lignites can be subjected to repeated freezing-thawing and wetting-drying, which determines the possibility of changing their grain-size composition and structure. Experimental studies in laboratory conditions on the influence of cyclic freezing-thawing (FTC) and wetting-drying (WDC) on the quality indicators of lignites have been carried out, their granulometric (fractional) composition has been studied. Freezing-thawing cycle conditions are as follows (FTC): minimum exposure temperature: -20°C;maximum: +5°C;relative humidity: 30%;number of processing cycles: 3. Wetting-drying cycles are as follows (WDC): drying temperatures are +20, +40, +60, +80°C, drying time 90 minutes, the coals are further subjected to rain (soaking) for a period of water saturation to humidity of 30% - 40% and dry again. The number of wetting-drying cycles is 3 times. The tests have revealed the destructive effects of FTC and WDC on the samples of lower metamorphic grade coal, and the cycles of wet-dry lead to the much higher yield of fine sizes (-6+0;-13+0 mm) than the cycles of freeze-thaw. Furthermore, it is found that the increase in the yield of fines depends on the heating temperature: coal disintegration proceeds more intensively at a higher temperature of drying.

关键词： Lignite Freezing-Thawing Cycle Wetting-Drying Cycle Grain size Composition Dust Coal storage Loss Quality

A Dimensional Reduction Approach Based on Essential Constraints in Linear Programming

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American Journal of Operations Research 2024年第1期14卷 1-31页

作者： Eirini i. Nikolopoulou George s. Androulakis Department of Mathematics University of Patras Patras Greece Department of Business Administration University of Patras Patras Greece

This paper presents a new dimension reduction strategy for medium and large-scale linear programming problems. The proposed method uses a subset of the original constraints and combines two algorithms: the weighted average and the cosine simplex algorithm. The first approach identifies binding constraints by using the weighted average of each constraint, whereas the second algorithm is based on the cosine similarity between the vector of the objective function and the constraints. These two approaches are complementary, and when used together, they locate the essential subset of initial constraints required for solving medium and large-scale linear programming problems. After reducing the dimension of the linear programming problem using the subset of the essential constraints, the solution method can be chosen from any suitable method for linear programming. The proposed approach was applied to a set of well-known benchmarks as well as more than 2000 random medium and large-scale linear programming problems. The results are promising, indicating that the new approach contributes to the reduction of both the size of the problems and the total number of iterations required. A tree-based classification model also confirmed the need for combining the two approaches. A detailed numerical example, the general numerical results, and the statistical analysis for the decision tree procedure are presented.

关键词： Linear Programming Binding Constraints Dimension Reduction Cosine similarity Decision Analysis Decision Trees

sANC Monte Carlo programs for small-angle Bhabha scattering

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Chinese Physics C 2024年第4期48卷 14-19页

作者： A.B.Arbuzov s.G.Bondarenko i.R.Boyko L.V.Kalinovskaya A.A.Kampf R.R.sadykov V.L.Yermolchyk Bogoliubov Laboratory of Theoretical Physics JINRDubna141980 Russia Dzhelepov Laboratory of Nuclear Problems JINRDubna141980 Russia Dubna state University Dubna141982 Russia

Luminosity monitoring at e^(+)e^(−)colliders was investigated using sANC Monte Carlo event generator RenesANCe and integrator MCsANC for simulation of Bhabha scattering at low *** are presented for center-of-mass energies of the Z boson resonance and at 240 GeV for the conditions of typical luminosity *** is shown that bremsstrahlung events with extremely low electron scattering angles are relevant to match the precision tags of future electron-positron colliders.

关键词： luminosity Bhabha scattering QED Monte Carlo simulation

Quantum algorithms for matrix operations and linear systems of equations

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Communications in Theoretical Physics 2024年第3期76卷 100-112页

作者： Wentao Qi Alexandr i Zenchuk Asutosh Kumar Junde Wu school of Mathematical sciences Zhejiang UniversityHangzhou 310027China Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry RAs ChernogolovkaRussia P.G.Department of Physics Gaya CollegeMagadh UniversityRampurGaya 823001India Harish-Chandra Research institute HBNIChhatnag RoadJhunsiPrayagraj 211019India Vaidic and Modern Physics Research Centre Bhagal BhimBhinmalJalore 343029India

Fundamental matrix operations and solving linear systems of equations are ubiquitous in scientific *** the‘sender-receiver’model,we propose quantum algorithms for matrix operations such as matrix-vector product,matrix-matrix product,the sum of two matrices,and the calculation of determinant and inverse *** encode the matrix entries into the probability amplitudes of the pure initial states of *** applying proper unitary transformation to the complete quantum system,the desired result can be found in certain blocks of the receiver’s density *** quantum protocols can be used as subroutines in other quantum ***,we present an alternative quantum algorithm for solving linear systems of equations.

关键词： matrix operation systems of linear equations ‘sender-receiver’quantum computation model quantum algorithm

Phase composition,conductivity,and sensor properties of cerium-doped indium oxide

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Nano Materials science 2024年第2期6卷 193-200页

作者： M.i.ikim G.N.Gerasimov V.F.Gromov O.J.ilegbusi L.i.Trakhtenberg N.N.semenov Federal Research Center for Chemical Physics of RAs MoscowRussia University of Central Florida OrlandoFLUSA Moscow institute of Physics and Technology(state University) DolgoprudnyMoscow RegionRussia Lomonosov Moscow state University MoscowRussia

The hydrothermal synthesis of in_(2)O_(3)and CeO_(2)–in_(2)O_(3)is investigated as well as the properties of sensor layers based on these *** the synthesis of in_(2)O_(3),intermediate products in(OH)_(3)and inOOH are formed,which are the precursors of stable cubic(c-in_(2)O_(3))and metastable rhombohedral(rh-in_(2)O_(3))phases,respectively.A transition from c-in_(2)O_(3)to rh-in_(2)O_(3)is observed with the addition of CeO_(2).The introduction of cerium into rh-in_(2)O_(3)results in a decrease in the sensor response to hydrogen,while it increases in composites based on c-in_(2)O_(3).The data on the sensor activity of the composites correlate with XPs results in which CeO_(2)causes a decrease in the concentrations of chemisorbed oxygen and oxygen vacancies in rh-in_(2)O_(3).The reverse situation is observed in composites based on c-in_(2)O_(3).Compared to in_(2)O_(3)and CeO_(2)–in_(2)O_(3)obtained by other methods,the synthesized composites demonstrate maximum response to H_(2)at low temperatures by 70–100℃,and have short response time(0.2–0.5 s),short recovery time(6–7 s),and long-term stability.A model is proposed for the dependence of sensitivity on the direction of electron transfer between in_(2)O_(3)and CeO_(2).

关键词： Cerium oxide indium oxide Nanocomposite Hydrothermal method Cubic phase Rhombohedral phase sensor response Conductivity Hydrogen Response/recovery time

Competitive effect, but not competitive response, varies along a climatic gradient depending on tree species identity

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Forest Ecosystems 2024年第2期11卷 142-151页

作者： Teresa Valor Lluís Coll David i.Forrester Hans Pretzsch Miren del Río Kamil Bielak Bogdan Brzeziecki Franz Binder Torben Hilmers Zuzana sitková Roberto Tognetti Aitor Ameztegui Department of Agricultural and Forest sciences and Engineering(DCEFA) University of LleidaAv.Alcalde Rovira Roure 191E25198 LleidaSpain Joint Research Unit CTFC-AGROTECNiO-CERCA Ctra.Sant LlorençKm.225280SolsonaSpain swiss Federal institute of Forest Snow and Landscape Research WSLZürcherstrasse 1118903BirmensdorfSwitzerland CsiRO Land and Water GPO Box 1700CanberraACT2601Australia Chair of Forest Growth and Yield science School of Life Sciences WeihenstephanTechnical University of MunichHans-Carl-Von-Carlowitz-Platz 285354FreisingGermany Forest Research Center INIA-CSICCtra.A Coruña Km 7.528040MadridSpain iuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIASpain Department of silviculture Institute of Forest SciencesWarsaw University of Life SciencesNowoursynowska 159/3402776WarsawPoland Bavarian state institute of Forestry(LWF) Hans-Carl-von-Carlowitz-Platz 1D-85354FreisingGermany National Forest Centre Forest Research InstituteT.G.Masaryka 2296001ZvolenSlovakia Faculty of Agricultural Environmental and Food SciencesFree University of Bozen-Bolzano Piazza Università1 I-39100Bolzano

Background: Understanding the role of species identity in interactions among individuals is crucial for assessing the productivity and stability of mixed forests over time. However, there is limited knowledge concerning the variation in competitive effect and response of different species along climatic gradients. in this study, we investigated the importance of climate, tree size, and competition on the growth of three tree species: spruce(Picea abies), fir(Abies alba), and beech(Fagus sylvatica), and examined their competitive response and effect along a climatic ***: We selected 39 plots distributed across the European mountains with records of the position and growth of 5,759 individuals. For each target species, models relating tree growth to tree size, climate and competition were proposed. Competition was modelled using a neighbourhood competition index that considered the effects of inter-and intraspecific competition on target trees. Competitive responses and effects were related to *** methods and information theory were used to select the best ***: Our findings revealed that competition had a greater impact on target species growth than tree size or climate. Climate did influence the competitive effects of neighbouring species, but it did not affect the target species? response to competition. The strength of competitive effects varied along the gradient, contingent on the identity of the interacting species. When the target species exhibited an intermediate competitive effect relative to neighbouring species, both higher inter-than intraspecific competitive effects and competition reduction occurred along the gradient. Notably, species competitive effects were most pronounced when the target species' growth was at its peak and weakest when growing conditions were far from their ***: Climate modulates the effects of competition from neighbouring trees on the target tree and not the susceptibility of th

关键词： Competition coefficient Competition reduction interspecific competition intraspecific competition Mixing effects Mixed species forest Neighbourhood models Plant-plant interactions