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Journal of Forestry Research 2024年第5期35卷 26-36页

作者： Andrés Baietto Andrés Hirigoyen Jorge Hernández Amabelia del Pino Forest Department Faculty of AgronomyUniversity of the Republic12900 MontevideoUruguay National Research Program of Forest Production National Agriculture Research InstituteINIA97000 TacuarembóUruguay soil and Water Department Faculty of AgronomyUniversity of the Republic12900 MontevideoUruguay

Native grasslands in the Pampas of south America are increasingly being replaced by Eucalyptus and Pinus *** short rotation regimes used for the stands require high nutrient levels,with litterfall being a major source of nutrient *** model the litterfall production using climatic variables and assess the nutrient return in 14-year-old Eucalyptus grandis and Pinus taeda stands,we measured litter production over 2 years,using conical litter traps,and monitored climatic *** temperature,accumulated precipitation,and mean maximum vapor pres-sure deficit at the seasonal level influenced litterfall produc-tion by ***;seasonal accumulated precipitation and mean maximum temperature affected litterfall by *** regression tree modeling based on these climatic vari-ables had great accuracy and predictive power for ***(N=33;MAE(mean absolute error)=0.65;RMsE(root mean square error)=0.91;R^(2)=0.71)and ***(N=108;MAE=1.50;RMsE=1.59;R^(2)=0.72).The nutrient return followed a similar pattern to litterfall deposition,as well as the order of importance of macronutrients(***:Ca>N>K>Mg>P;***:N>Ca>K>Mg>P)and micronutrients(*** and ***:Mn>Fe>Zn>Cu)in both *** study constitutes a first approximation of factors that affect litterfall and nutrient return in these systems.

关键词： Afforestation Litterfall Nutrient recycling Climate modeling Myrtaceae Pinaceae

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Exploring van der Waals materials with high anisotropy:geometrical and optical approaches

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Light(science & Applications) 2024年第4期13卷 645-653页

作者： Aleksandr s.slavich georgy A.Ermolaev Mikhail K.Tatmyshevskiy Adilet N.Toksumakov Olga g.Matveeva Dmitriy V.grudinin Kirill V.Voronin Arslan Mazitov Konstantin V.Kravtsov Alexander V.syuy Dmitry M.Tsymbarenko Mikhail s.Mironov sergey M.Novikov Ivan Kruglov Davit A.ghazaryan Andrey A.Vyshnevyy Aleksey V.Arsenin Valentyn s.Volkov Kostya s.Novoselov Moscow Center for Advanced studies Kulakova str.20Moscow 123592Russia. Emerging Technologies Research Center XPANCEOInternet CityEmmay TowerDubaiUnited Arab Emirates. Donostia International Physics Center(DIPC) Donostia/San-Sebastián 20018Spain. Institute of Materials Ecole Polytechnique Federale de Lausanne1015 LausanneSwitzerland. Department of Chemistry Lomonosov Moscow State UniversityMoscow 119991Russia. Laboratory of Advanced Functional Materials Yerevan State UniversityYerevan 0025Armenia. National graphene Institute(NgI) University of ManchesterManchester M139PLUK. Department of Materials science and Engineering National University of SingaporeSingapore 03-09 EASingapore. Institute for Functional Intelligent Materials National University of Singapore117544 SingaporeSingapore

The emergence of van der Waals(vdW)materials resulted in the discovery of their high optical,mechanical,and electronic anisotropic properties,immediately enabling countless novel phenomena and *** success inspired an intensive search for the highest possible anisotropic properties among vdW ***,the identification of the most promising among the huge family of vdW materials is a challenging quest requiring innovative ***,we suggest an easy-to-use method for such a survey based on the crystallographic geometrical perspective of vdW materials followed by their optical *** our approach,we found As2s3 as a highly anisotropic vdW *** demonstrates high in-plane optical anisotropy that is~20%larger than for rutile and over two times as large as calcite,high refractive index,and transparency in the visible range,overcoming the century-long record set by *** these benefits,As2s3 opens a pathway towards nextgeneration nanophotonics as demonstrated by an ultrathin true zero-order quarter-wave plate that combines classical and the Fabry–Pérot optical phase ***,our approach provides an effective and easy-to-use method to find vdW materials with the utmost anisotropic properties.

关键词： anisotropy anisotropic high

Forensic significance of Touch Deoxyribonucleic Acid

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Journal of Forensic science and Medicine 2024年第3期10卷 214-219页

作者： g.Devika s.Vaishnavi Manashree Mane Department of Forensic science National Forensic Sciences UniversityPondaGoaIndia Department of Forensic science School of SciencesJain(Deemed-to-be University)BengaluruKarnatakaIndia

Touch deoxyribonucleic acid(DNA)refers to the DNA that is left behind from skin cells when a person touches or comes into contact with an *** crimes where the identification of suspects becomes a challenge,touch DNA has been a proven investigative *** present study aims to provide a systematic review of the role of touch DNAin criminal cases which discusses the nature and importance of touch DNA evidence at crime scenes;various phenomena including the transfer and persistence of touched samples;different factors affecting the touch sample deposition and DNA shedding;the best recovery methods and collection of samples from different substrates;and the interpretation of profiles through advanced techniques that identify the *** present study also aims to optimize standard protocols in the laboratories for touched samples appropriate to the substrates that improve the success rate of profiles from touched items.

关键词： Crime scene investigation forensic deoxyribonucleic acid analysis touch deoxyribonucleic acid touch deposits trace

Cross-method Analysis of Corotation Radii Data set for spiral galaxies

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Research in Astronomy and Astrophysics 2024年第7期24卷 95-110页

作者： V.s.Kostiuk A.A.Marchuk A.s.gusev sternberg Astronomical Institute Lomonosov Moscow State UniversityUniversitetsky pr.13119234 MoscowRussia Central(Pulkovo)Astronomical Observatory Russian Academy of SciencesPulkovskoye chaussee 65/1196140 St.PetersburgRussia saint Petersburg state University Universitetsky pr.28198504 St.PetersburgRussia

A corotation radius is a key characteristic of disk galaxies that is essential to determine the angular speed of the spiral structureΩ_p,and therefore understand its *** the literature,there are plenty of methods to estimate this value,but do these measurements have any consistency?In this work,we collected a data set of corotation radius measurements for 547 galaxies,300 of which had at least two *** initial analysis reveals that most objects have rather inconsistent corotation radius ***,a significant fraction of galactic disks is distinguished by a large error coverage and almost uniform distribution of *** findings do not have any relation to spiral type,Hubble classification,or presence of a *** other reasons,obtained results could be explained by the transient nature of spirals in a considerable part of *** have made our collected data sample publicly available,and have demonstrated on one example how it could be useful for future research by investigating a winding time value for a sample of galaxies with possible multiple spiral arm patterns.

关键词： galaxies fundamental parameters-galaxies kinematics and dynamics-galaxies structure

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Fault Location Method for Overhead Feeders with Distributed generation Units Based on Direct Load Flow Approach

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Journal of Modern Power systems and Clean Energy 2024年第4期12卷 1135-1146页

作者： Charalampos g.Arsoniadis Vassilis C.Nikolaidis Department of Electrical and Computer Engineering Democritus University of ThraceXanthi 67100Greece

This paper proposes a novel fault location method for overhead feeders,which is based on the direct load flow *** method is developed in the phase domain to effec-tively deal with unbalanced network conditions,while it can al-so handle any type of distributed generation(Dg)units without requiring equivalent *** utilizing the line series parame-ters and synchronized or unsynchronized voltage and current phasor measurements taken from the sources,the method reli-ably identifies the most probable faulty *** the aid of an index,the exact faulty section among the multiple candi-dates is *** simulation studies for the IEEE 123-bus test feeder demonstrate that the proposed method accu-rately estimates the fault position under numerous short-circuit conditions with varying pre-fault system loading conditions,fault resistances,and measurement *** proposed meth-od is promising for practical applications due to the limited number of required measurement devices as well as the short computation time.

关键词： Fault location distribution system direct load flow distributed generation

Comparative measurement of CO_(2),CH_(4)and CO at two traffic interjunctions having inflated vehicular flow in Delhi

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Journal of Environmental sciences 2024年第7期141卷 314-329页

作者： Komal Daya soni Khem singh shankar g.Aggarwal CsIR-National Physical Laboratory Dr.K.S.Krishnan MargNew Delhi 110012India Academy of scientific&Innovative Research(AcsIR) Ghaziabad 201002India

Vehicular emissions are considered one of the major anthropogenic sources of greenhouse gases and poor air quality in metropolitan *** study aims to see the correlation of CO_(2),CH_(4),and CO through monitoring over a period from December 2020 to October 2021 covering three seasons’winter,summer,and monsoon at two different traffic locations of Delhi having different traffic volumes,road patterns,and traffic *** annual average morning concentration of CO_(2),CH_(4)and CO was found(533±105),(7.3±3.1),(10.7±3.0)ppm at Najafgarh and(480±70),(5.2±1.8),(7.8±2.8)ppm at Rajendra Place,respectively.A relationship between concentration of all three gases and meteorological parameters such as temperature,humidity,wind speed and wind direction has also been investigated using Pearson correlation coefficient and pollution rose diagram.A comparable pattern in concentration was observed for all three gases in spatial(location)and temporal(diurnal)*** concentration trend of CO_(2)in different seasons is winter>summer>monsoon,while in the case of CH_(4)winter=summer>monsoon but not any seasonal trend was noted in CO *** is observed that CO_(2)has a good relation with CO(a tracer for vehicular emission)in terms of diurnal variation,whereas,CH_(4)does not represent a relation with CO and CO_(2)diurnally,suggesting that vehicles are the source of CO_(2)but not much contributing to other greenhouse gases like CH_(4).

关键词： Vehicular emission greenhouse gases Harmful pollutants Meteorological parameters

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Current state-of-the-art review of footwear–ground friction

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Friction 2024年第10期12卷 2188-2204页

作者： David REBENDA Tomáš sÁHA Footwear Research Centre University InstituteTomas Bata University in ZlinZlin 76001Czech Republic Faculty of Mechanical Engineering Brno University of TechnologyBron 61600Czech Republic

The most important role of footwear is to ensure safe,functional walking,and foot *** the proper functionality of not only the work shoes,the anti-slip behavior of the shoe under various conditions and environments plays an important role in the prevention of slips,trips,falls,and consequent *** article is intended to review the current understanding of the frictional mechanisms between shoe outsoles and various counterfaces that impact the evaluation of outsole *** research focuses on the mechanisms driving outsole friction on different ground surfaces or the definition and description of parameters that influence outsole ***,the review discusses the effect of various surface contaminants on footwear ***,challenges and outlooks in the field of footwear outsoles are briefly mentioned.

关键词： shoe outsole composite slipperiness coefficient of friction(COF) adhesion safe walk

Optimal Control of service Rates of Discrete-Time(s,Q)Queueing-Inventory systems with Finite Buffer

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Journal of systems science and systems Engineering 2024年第3期33卷 261-280页

作者： L.Iniya B.sivakumar g.Arivarignan school of Mathematics Madurai Kamaraj UniversityMaduraiTamilnaduIndia Department of statistics Manonmaniam Sundaranar UniversityTirunelveliTamilnaduIndia

This article,we develop an optimal policy to control the service rate of a discrete time queueing-inventory system with finite *** customers arrive according to a Bernoulli process and the service time for the customers are *** the buffer size attains its maximum,any arriving new customers are considered to be *** customers are served one by one according to FCFs rule and each customers request random number of *** inventory is replenished according to a(s,Q)inventory policy with geometric lead *** main objectives of this article are to determine the service rates to be employed at each slot so that the long run expected cost rate is minimized for fixed inventory level and fixed buffer size and to minimize the expected waiting time for a fixed inventory level and fixed buffer *** problems are modelled as Markov decision *** establish the existence of a stationary policy and employ linear programming method to find the optimal service *** provide some numerical examples to illustrate the behaviour of the model.

关键词： Queueing-inventory system discrete time batch demand-Markov decision process

The great catastrophe: causes of the Permo-Triassic marine mass extinction

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National science Review 2024年第1期11卷 37-50页

作者： Paul B.Wignall David P.g.Bond school of Earth & Environment University of Leeds school of Environmental sciences University of Hull

The marine losses during the Permo-Triassic mass extinction were the worst ever experienced. All groups were badly affected, especially amongst the benthos(e.g. brachiopods, corals, bryozoans, foraminifers,ostracods). Planktonic populations underwent a fundamental change with eukaryotic algae being replaced by nitrogen-fixing bacteria, green-sulphur bacteria, sulphate-reducing bacteria and prasinophytes. Detailed studies of boundary sections, especially those in south China, have resolved the crisis to a ～55 kyr interval straddling the Permo-Triassic boundary. Many of the losses occur at the beginning and end of this interval painting a picture of a two-phase extinction. Improved knowledge of the extinction has been supported by numerous geochemical studies that allow diverse proposed extinction mechanisms to be studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections globally, although the intensity and timing shows regional variability. Decreased ocean ventilation coincides with rapidly rising temperatures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting support from geochemical proxies and, even less likely, siltation(burial under a massive influx of terrigenous sediment) which lacks substantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the Permian was likely siberian Trap eruptions and their associated carbon dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter episodes stemming from siberian volcanism have also been linked to the crisis, but the short-term nature of these episodes(s) and the overwhelming evidence for rapid warming during the crisis makes this an unlikely cause. Finally, whilst the extinction is well studied in equatorial latitudes, a different history is found in northern Boreal latitudes

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic winter

Uncovering the dominant contribution of intermediate volatility compounds in secondary organic aerosol formation from biomass-burning emissions

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National science Review 2024年第3期11卷 150-158页

作者： Kun Li Jun Zhang David M.Bell Tiantian Wang Houssni Lamkaddam Tianqu Cui Lu Qi Mihnea surdu Dongyu Wang Lin Du Imad El Haddad Jay g.slowik Andre s.H.Prevot Environment Research Institute Shandong University Laboratory of Atmospheric Chemistry Paul Scherrer Institute

Organic vapors from biomass burning are a major source of secondary organic aerosols(sOAs). Previous smog chamber studies found that the sOA contributors in biomass-burning emissions are mainly volatile organic compounds(VOCs). While intermediate volatility organic compounds(IVOCs) are efficient sOA precursors and contribute a considerable fraction of biomass-burning emissions, their contribution to sOA formation has not been directly observed. Here, by deploying a newly-developed oxidation flow reactor to study sOA formation from wood burning, we find that IVOCs can contribute ～70% of the formed sOA, i.e.>2 times more than VOCs. This previously missing sOA fraction is interpreted to be due to the high wall losses of semi-volatile oxidation products of IVOCs in smog chambers. The finding in this study reveals that sOA production from biomass burning is much higher than previously thought, and highlights the urgent need for more research on the IVOCs from biomass burning and potentially other emission sources.

关键词： atmospheric chemistry biomass burning secondary organic aerosol intermediate volatility organic compounds