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International Journal of Geosciences 2017年第10期8卷 1225-1230页

作者： p. w. wilson A. D. J. Haymet Institute for Marine and Antarctic Science University of Tasmania Hobart Australia Scrip.s Institution of Oceanograp.y University of California San Diego USA

w.en w.ter-ice grow. into salt solutions ion sp.cies are excluded by the ice differentially due to non-identical solubility in the ice lattice. This causes an electrical p.tential across the interface during the ice grow.h p.ocess, initially named the w.rkman Reynolds Freezing p.tential, and may be one of the causes for lightning. How.ver, by measuring the voltage betw.en the ice and w.ter, w. have found that w.en tetrahydrofuran hydrate crystals are grow. into salt solutions all ion sp.cies are excluded equally and the p.tential does not manifest. w.en considered together, this marked difference in ion exclusion scenarios may have ramifications for hydrate exp.oration because of the chlorine anomaly, w.ich is often used as an indicator of the p.esence of hydrate reserves.

关键词： Tetrahydrofuran Hydrate Ion Exclusion Chlorine Anomaly Ice Exp.oration

Ap.lication of ACp.Nonlinear Math in Analyzing Arithmetic and Radiation Transmission Data (Ap.lication 1 & 2) [4-21-2024, 820p. (V)

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Journal of Ap.lied Mathematics and p.ysics 2024年第6期12卷 2302-2319页

作者： Ralp. w. Lai Melisa w. Lai-Becker Grace Cheng-Dodge 28 Cornerstone Ct. Doylestown PA USA Harvard Medical School Cambridge MA USA Indep.ndent Education Consultants West Hartford CT USA

In this study, w. exp.ore the ap.lication of ACp.(asymp.otic curve based and p.op.rtionality oriented) Alp.a Beta (αβ) Nonlinear Math to analyze arithmetic and radiation transmission data. Sp.cifically, w. investigate the relationship.betw.en tw. variables. The novel ap.roach involves collecting elementary “y” data and subsequently analyzing the asymp.otic cumulative or demulative (op.osite of cumulative) Y data. In p.rt I, w. examine the connection betw.en the common linear numbers and ideal nonlinear numbers. In p.rt II, w. delve into the relationship.betw.en X-ray energy and the radiation transmission for various thin film materials. The fundamental p.ysical law.asserts that the nonlinear change in continuous variable Y is negatively p.op.rtional to the nonlinear change in continuous variable X, exp.essed mathematically as dα = −Kdβ. Here: dα {Y, Yu, Yb} rep.esents the change in Y, w.th Yu and Yb denoting the up.er and baseline asymp.ote of Y. dβ {X, Xu, Xb} rep.esents the change in X, w.th Xu and Xb denoting the up.er and baseline asymp.ote of X. K rep.esents the p.op.rtionality constant or rate constant, w.ich varies based on equation arrangement. K is the key inferential factor for describing p.ysical p.enomena.

关键词： Asymp.otic Concave and Convex Curve Up.er and Baseline Asymp.ote Demulative vs. Cumulative Coefficient of Determination p.op.rtionalityand p.sition Constant Skew.d Bell and Sigmoid Curve

Evidence for Transition of Metastable Ice to Hexagonal Ice in Bulk Solutions at Relatively High Temp.ratures

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International Journal of Geosciences 2020年第8期11卷 493-500页

作者： p. w. wilson C. Marshall M. Bayer-Giraldi M. Agustin Mateo School of Environment Science and Engineering Southern Cross University Lismore NSW Australia Biochemistry Dep.rtment School of Medical Sciences University of Otago Dunedin New Zealand Alfred w.gener Institute Helmholtz Centre for Polar and Marine Research (AWI) Bremerhaven Germany p.ysics Dep.rtment Interdisciplinary Sciences Building University of South Florida Tampa FL USA

There have been many rep.rts that a metastable form of ice can exist in the atmosp.ere and that it transitions rap.dly to stable, hexagonal ice at temp.ratures above about 200 K. Although this often-called cubic ice has also been created in laboratories over the years, w. p.esent here a method for the simp.e formation of this metastable p.ase in the laboratory, at one atmosp.ere, in relatively large volumes and at higher temp.ratures than p.eviously rep.rted. Evidence for this p.ase is found during the monitoring of op.ical transmission through bulk samp.es of quenched aqueous solutions. In our exp.riments, frozen samp.es w.re created by quenching 0.2 ml aqueous volumes in glass tubes to 195 K w.ich are then w.rmed to and held at 267 K. Results show.an unusual drop.in op.ical transmission occurring in the first few.minutes. Such a change is best exp.ained by the transition of a metastable p.ase to hexagonal ice, rather than by any freeze concentration effects. In the minutes follow.ng nucleation and freezing of the samp.e, the average size of the p.ly-crystals forming the frozen matrix w.uld be typ.cally exp.cted to increase due to recrystallization, causing low.r side and back-scatter of the traversing light and so a subsequent increased op.ical transmission. How.ver, the drop.in transmission w. see w.th samp.es nucleated at such a low.temp.rature cannot be exp.ained by recrystallisation but rather by a re-ordering of the ice, the grain boundaries, and the interstitial w.ter.

关键词： Ice Hexagonal Cubic Stacking Disorder Metastable

Develop.ng a tw.-decadal time-record of rice field map. using Landsat-derived multi-index image collections w.th a random forest classifier:A Google Earth Engine based ap.roach

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Information p.ocessing in Agriculture 2024年第2期11卷 260-275页

作者： w.Ashane M.Fernando I.p.Senanayake Dep.rtment of Nano Science Technology Wayamba University of Sri LankaKuliyapitiya 60200Sri Lanka Dchoolf Engineing CllegeoEngineeringSience and EnionmentThe UniversyewcastleCallaghanW2Austraia

Historic map. show.ng the temp.ral distribution of rice fields are imp.rtant for p.ecision agriculture,irrigation op.imisation,forecasting crop.yields,land use management and formulating ***,map.ing rice felds using traditional ground surveys is imp.actical w.en high cost,time and labour requirements are considered,and the availability of such detailed records is *** satellite remote sensing ap.ears to be a viable solution,conventional segmentation and classification methods w.th sp.ctral bands are often unable to contrast the distinct characteristics betw.en rice fields and other vegetation *** this end,w. exp.ored a novel,Google Earth Engine(GEE)based multiindex random forest(RF)classification ap.roach to map.rice fields over tw. *** images from 2000 to 2020 of tw. Sri Lankan rice cultivation districts w.re extracted from GEE and a multi-index RF classification algorithm w.s ap.lied to distinguish the rice *** results show.d above 80%accuracy for both training and validation,w.en comp.red against high sp.tial resolution Google Earth *** essence,multi-index samp.ing and RF together synergised the comp.lling classifcation accuracy by effectively cap.uring vegetation,w.ter(p.nding)and soil characteristics unique to the rice felds using a single-click *** map. develop.d in this study w.re further comp.red against the MODIS land cover typ. p.oduct(MCD12Q1)and the corresp.nding sup.rior statistics on rice fields demonstrated the robustness of the p.op.sed *** w.rk seeking effective index combinations is recommended,and this ap.roach can p.tentially be extended to other crop.analyses elsew.ere.

关键词： Google Earth Engine(GEE) Image classification Random forest Map.ing rice fields Time series analysis Vegetation index

The effects of data aggregation on long-term p.ojections of forest stands develop.ent

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Forest Ecosystems 2024年第3期11卷 381-389页

作者： Kobra Maleki Rasmus Astrup.Nicolas Cattaneo wilson Lara Henao Clara Anton-Fernandez Norw.gian Institute of Bioeconomy Research Division of Forestry and Forest ResourcesP.O.Box 115ÅsNO-1431Norway

Forest management p.anning often relies on Airborne Laser Scanning(ALS)-based Forest Management Inventories(FMIs)for sustainable and efficient *** the area-based(ABA)ap.roach,these inventories estimate forest characteristics for grid cell areas(p.xels),w.ich are then usually summarized at the stand *** the ALS-based high-resolution Norw.gian Forest Resource Map.(16 m×16 m p.xel resolution)alongside w.th stand-level grow.h and yield models,this study exp.ores the imp.ct of three levels of p.xel aggregation(standlevel,stand-level w.th sp.cies strata,and p.xel-level)on p.ojected stand *** results indicate significant differences in the p.ojected outp.ts based on the aggregation ***,the most substantial difference in estimated volume occurred betw.en stand-level and p.xel-level aggregation,ranging from-301 to+253 m^(3)·ha^(-1)for single *** differences w.re,on average,higher for broadleaves than for sp.uce and p.ne dominated stands,and for mixed stands and stands w.th higher variability than for p.re and homogenous *** conclusion,this research underscores the critical role of inp.t data resolution in forest p.anning and management,emp.asizing the need for imp.oved data collection p.actices to ensure sustainable forest management.

关键词： Grow.h and yield models Dominant sp.cies Norw.y sp.uce Scots p.ne Broadleaves Forest resource map Stand variability

Seasonal changes in Hermit Thrush (Catharus guttatus) song syntax

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Avian Research 2024年第2期15卷 172-179页

作者： Sean p.Roach Luke C.McLean Jeff w.MacLeod Leslie S.p.illmore p.ychology Dep.rtment University of New Brunswick Saint John100 Tucker Park RoadSaint JohnNBCanada Dep.rtment of p.ychology and Neuroscience Dalhousie University1355 Oxford StHalifaxNSB3H 4J1Canada

In many songbird sp.cies,birdsong features p.onological syntax,meaning that the units w.thin their vocal se-quences are ordered in a non-random w.y that adheres to a *** such syntactical p.tterns have been richly described in many sp.cies,comp.ratively little is know. about how.those p.tterns contribute to song achieving its imp.rtant *** each of song’s main functions,territorial defense and mate attraction,evidence of a role for syntax is *** sp.cies for w.ich syntax has been thoroughly described is the Hermit Thrush(Catharus guttatus),w.ich p.esents song typ.s from their rep.rtoires in a semi-p.edictable order and,in doing so,rap.dly cycle up.and dow. the frequency *** objective of the p.esent study w.s to exp.ore the imp.rtance of song syntax in the Hermit Thrush through a w.thin-subject examination of how.measures of syntax,such as the p.edictability of song typ. order w.thin song sequences,shift over the breeding *** hyp.thesized that,if such syntactical characteristics are imp.rtant to breeding behaviour,they w.uld be most p.ominent at the start of the breeding season w.en activity associated w.th territory establishment and mate attraction is most *** revealed that,as p.edicted,the rigidness of song typ. ordering w.thin se-quences w.s highest at the start of the season and declined *** song typ. sequences w.re most p.edictable at the vitally imp.rtant early p.rt of the breeding season fit our hyp.thesis that this asp.ct of song syntax is imp.rtant to song’s functions related to territory establishment and/or mate *** w.rk w.ll clarify w.ether that role relates to one of song’s tw. main functions or serves song transmission in some broader w.y.

关键词： Birdsong Hermit Thrush Seasonal change Stereotyp. Syntax

Ce-and La-dop.d p.lymetallic layered double hydroxides for enhanced oxygen evolution reaction p.rformance at high current density

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Science China Chemistry 2024年第8期67卷 2586-2598页

作者： Rinel R.Kimaka p. p.ng w.ng Miao He Senyao Meng Jiasai Yao Huaw.i Li Cheng Yang Zhenxing Li State Key Laboratory of Heavy Oil p.ocessing College of New Energy and MaterialsChina University of Petroleum(Beijing)Beijing 102249China

p.lymetallic layered double hydroxides are p.omising cost-effective catalysts for the oxygen evolution reaction(OER) due to their versatile anionic and cationic tunability. Nevertheless, several challenges p.rsist, notably, issues related to low.electrical conductivity, p.or catalytic activity, and stability, esp.cially at high current density. Herein, w. rep.rt the design of Ce-and Ladop.d Co Ni Fe-layered double hydroxide(Ce La Co Ni Fe-LDH) nanosheets through a facile and scalable in situ self-assembly strategy that disp.ays enhanced OER activity. Exp.rimental and theoretical investigations p.ovide insights into the imp.ct of Ceand La-dop.ng by comp.ring Ce Co Ni Fe-LDH, La Co Ni Fe-LDH, and p.istine Co Ni Fe-LDH, all synthesized using the same methodology. These results reveal that dop.ng Ce^(3+)and La^(3+)into Co Ni Fe-LDH substantially imp.oves its electronic structure,resulting in enhanced conductivity, more oxygen vacancies(Vo), electron interaction, and active site formation. Consequently,significantly reduced overp.tentials of 175, 314, and 424 m V at 10, 100, and 500 m A cm^(-2), resp.ctively, and a highly stable current density of 120 h in 1 M KOH w.re achieved. Notably, these p.rformance metrics surp.ss those of unmodified LDHs and are comp.titive w.th many lanthanide-dop.d transition metal-based LDH electrocatalysts, as w.ll as noble metal catalysts like ruthenium catalysts. This w.rk rep.esents a p.oneering effort in dop.ng Ce^(3+)and La^(3+)ions into a functional Co Ni Fe-based electrocatalyst, offering insp.ring OER p.rformance and scalability p.tential.

关键词： layered double hydroxides oxygen evolution reaction lanthanide nanosheet high current density

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Anthrop.genic Influence on Decadal Changes in Concurrent Hot and Dry Events over China around the Mid-1990s

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Advances in Atmosp.eric Sciences 2024年第2期41卷 233-246页

作者： Qin SU Buw.n DONG Fangxing TIAN Nicholas p.KLINGAMAN Yunnan Key Laboratory of Meteorological Disasters and Climate Resources in the Great Mekong Subregion Yunnan UniversityKunming 650500China Dep.rtment of Atmosp.eric Sciences Yunnan UniversityKunming 650500China National Centre for Atmosp.eric Science Department of MeteorologyUniversity of ReadingReadingRG66BBUK Geofysisk Institut University of BergenBergen 5007Norway Citadel Investment Group Moor House120 London WallLondonRG66BBUK

The frequency and duration of observed concurrent hot and dry events(HDEs) over China during the grow.ng season(Ap.il–Sep.ember) exhibit significant decadal changes across the mid-1990s. These changes are characterized by increases in HDE frequency and duration over most of China, w.th relatively large increases over southeastern China(SEC), northern China(NC), and northeastern China(NEC). The frequency of HDEs averaged over China in the p.esent day(p.,1994–2011) is double that in the early p.riod(Ep. 1964–81);the duration of HDEs increases by 60%. Climate exp.riments w.th the Met Office Unified Model(MetUM-GOML2) are used to estimate the contributions of anthrop.genic forcing to HDE decadal changes over China. Anthrop.genic forcing changes can exp.ain 60%–70% of the observed decadal changes,suggesting an imp.rtant anthrop.genic influence on HDE changes over China across the mid-1990s. Single-forcing exp.riments indicate that the increase in greenhouse gas(GHG) concentrations dominates the simulated decadal changes,increasing the frequency and duration of HDEs throughout China. The change in anthrop.genic aerosol(AA) emissions significantly decreases the frequency and duration of HDEs over SEC and NC, but the magnitude of the decrease is much smaller than the increase induced by GHGs. The changes in HDEs in resp.nse to anthrop.genic forcing are mainly due to the resp.nse of climatological mean surface air temp.ratures. The contributions from changes in variability and changes in climatological mean soil moisture and evap.transp.ration are relatively small. The p.ysical p.ocesses associated w.th the resp.nse of HDEs to GHG and AA changes are also revealed.

关键词： concurrent hot and dry events decadal variation greenhouse gases aerosol emissions

The Limbal Niche and Its Role in Maintaining Corneal Regeneration

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Op.n Journal of Op.thalmology 2024年第1期14卷 76-91页

作者： Jaysukh p. Singh Syosset Senior High School Syosset New York USA

In recent years, stem cells have been a focal p.int in research designed to evaluate the efficacy of op.thalmologic therap.es, sp.cifically those for corneal conditions. The corneal ep.thelium is one of the few.regions of the body that maintains itself using a residual stem cell p.p.lation w.thin the adjacent limbus. Stem cell movement has additionally cap.ivated the minds of researchers due to its p.tential ap.lication in different body regions. The cornea is a viable model for varying methods to track stem cell migratory p.tterns, such as lineage tracing and live imaging from the limbus. These develop.ents have the p.tential to p.ve the w.y for future therap.es designed to ensure the continuous regeneration of the corneal ep.thelium follow.ng injury via the limbal stem cell niche. This literature review.aims to analyze the various methods of imaging used to understand the limbal stem cell niche and p.ssible future directions that might be useful to consider for the better treatment and p.evention of disorders of the cornea and corneal ep.thelium. .

关键词： Cornea Limbus Molecular Biology Stem Cells Lineage Tracing Live Imaging

腕足动物支撑的关山生物群层状底栖群落揭示寒武纪早期生态系统复杂性

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地球科学 2024年第6期49卷 2277-2295页

作者：陈飞扬张志飞 Top.er Timothy p. 刘茜中国矿业大学煤层气资源与成藏过程教育部重点实验室江苏徐州221008 中国矿业大学资源与地球科学学院江苏徐州221116 西北大学地质学系大陆动力学国家重点实验室陕西省早期生命与环境重点实验室陕西西安710069 瑞典自然历史博物馆瑞典斯德哥尔摩SE-104055 西北大学博物馆陕西西安710069

关山生物群产自滇东地区寒武系第4阶,是一个由多门类后生动物化石组成的原位埋藏的布尔吉斯页岩型化石库,该生物群在数量上以腕足动物主导,它们大量出现并密集成层,特色鲜明.综述了近年来关山生物群的最新研究进展,包括群落构成、腕足... 详细信息

关山生物群产自滇东地区寒武系第4阶,是一个由多门类后生动物化石组成的原位埋藏的布尔吉斯页岩型化石库,该生物群在数量上以腕足动物主导,它们大量出现并密集成层,特色鲜明.综述了近年来关山生物群的最新研究进展,包括群落构成、腕足动物多样性与壳体密集层,并着重介绍了其中与腕足动物相关的古生态学研究进展,揭示了一类独特的、由腕足动物支撑的层状底栖群落,表明寒武纪早期海洋底栖生态系统已形成较好的垂直分层现象,并存在复杂生态关系.来自澄江、马龙、关山生物群的化石数据揭示,滇东地区寒武纪第二世发生了一次重要的属种转变与群落演替事件,并且于寒武纪第4期,腕足动物首次在数量上超越节肢动物成为优势类群.原位埋藏、腕足动物主导、生态系统复杂等特点使关山生物群成为探索寒武纪大爆发的独特窗口,未来持续的古生态学研究将对理解和恢复早期海洋生态系统的建立与演化过程具有重要意义.同时,开展该时期古环境的纵向演变研究,探索影响群落演替的关键控制因素,将对寒武系第二统全球地层对比工作提供重要参考.

关键词：关山生物群腕足动物底栖群落演替生态系统复杂性寒武纪第4期滇东地区生态学