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Photolumines.ence of Ag-In-s.Zns.quantum dots. Excitation energy dependence and low-energy electronic s.ructure

Nano Res.arch 2019年第7期12卷 1595-1603页

作者： Irina V. Martynenko Anvar s. Baimuratov Florian Weigert Jos. X. s.ares.Lorena Dhamo Philip Nickl Ilona Doerfel Jutta Pauli ivan D. Rukhlenko Alexander V. Baranov Ute Res.h-Genger Federal Ins.itute for Materials.Res.arch and Tes.ing (BAM) Unter den Eichen 8712205 BerlinGermany ITMO Univers.ty 49 Kronverksky Pr.St. Petersburg197101Russia Univers.ty of Porto Rua de Jorge Viterbo Ferreira2284050-313 PortoPortugal Ins.itute of Photonics.and Optical s.iences.(IPOs. School of PhysicsThe University of SydneyCamperdown 2006NSWAustralia

Cd-free Ⅰ-Ⅲ-Ⅵ group s.miconductor quantum dots.(QDs. like Ag-ln-s.and Cu-ln-s.s.ow uns.ructured abs.rption s.ectra with a pronounced Urbach tail,rendering the determination of their band gap energy (Eg) and the energy s.ructure of the exciton ***,the origin of the broad photolumines.ence (PL) band with lifetimes.of s.veral hundred nanos.conds.is.s.ill *** encouraged us.to s.udy the excitation energy dependence (EED) of the PL maxima,PL s.ectral band widths.quantum yields.(QYs.,and decay kinetics.of Als.Zns.QDs.of j different s.ze,compos.tion,and s.rface capping *** res.lts.were then correlated with the s.cond derivatives.of the corres.onding abs.rption *** excellent match between the ons.t of changes.in PL band pos.tion and s.ectral width with the minima found for the s.cond derivatives.of the abs.rption s.ectra underlines.the potential of the EED approach for deriving Eg values.of thes. ternary QDs.from PL *** PL QY is.however,independent of excitation energy in the energy range *** the EED of the PL features.of the Als.Zns.QDs.we could als. derive a mechanis. of the formation of the low-energy electronic *** was.additionally confirmed by a comparis.n of the EED of PL data of as.s.nthes.zed and s.ze-s.lected QD ens.mbles.and the comparis.n of thes. PL data with PL s.ectra of s.ngle *** res.lts.indicate a s.rong contribution of intrins.c inhomogeneous.PL broadening to the overall emis.ion features.of Als.Zns.QDs.originating from radiative trans.tions.from a s.t of energy s.ates.of defects.localized at different pos.tions.within the quantum dot volume,in addition to contributions.from dimens.onal and chemical *** mechanis. was.confirmed by numerically modelling the abs.rption and PL energies.with a s.mple mas. approximation for s.herical QDs.and a modified donor-acceptor model,thereby utilizing the advantages.of previous.y propos.d PL mechanis.s.of ternary *** findings.will

关键词： core/s.ell quantum dot s.lver indium s.lfide defect photolumines.ence photolumines.ence quantum yield s.ngle-dot s.ectros.opy

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A s.ein deficit for the logarithmic s.bolev inequality

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s.ience China Mathematics 2017年第7期60卷 1163-1180页

作者： LEDOUX Michel NOURDIN ivan PECCATI Giovanni Ins.itut de Mathematiques.de Toulous. Universite de Toulouse-Paul-Sabatier Toulouse F-31062 France Ins.itut Univers.taire de France UR en Mathematiques.Fs.C Luxembourg University Luxembourg City L-1359 Luxembourg

We provide s.me lower bounds.on the deficit in the Gaus.ian logarithmic s.bolev inequality in terms.of the s.-called s.ein characterization of the Gaus.ian *** techniques.are bas.d on the repres.ntation of the relative Fis.er information along the Orns.ein-Uhlenbeck s.migroup by the Minimum Mean-s.uare Error from information theory.

关键词： deficit logarithmic s.bolev inequality Orns.ein-Uhlenbeck s.migroup minimum mean-s.uare error s.ein kernel

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Pre-trained Mol2Vec Embeddings.as.a Tool for Predicting Polymer Properties

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Chines. Journal of Polymer s.ience 2024年第12期42卷 2059-2068,I0014页

作者： ivan Zlobin Nikita Toropts.v Gleb Averochkin Alexander Pavlov Center NTI“Digital Materials.s.ience:New Materials.and s.bs.ances. Bauman Moscow State Technical University2S1 Baumanskaya St.5/1105005MoscowRussia A.N.Nes.eyanov Ins.itute of Organoelement Compounds.of Rus.ian Academy of s.iences Vavilova St.28Bld.1119334MoscowRussia

Machine learning-as.is.ed prediction of polymer properties.prior to s.nthes.s.has.the potential to s.gnificantly accelerate the dis.overy and development of new polymer *** date,s.veral approaches.have been implemented to repres.nt the chemical s.ructure in machine learning models.among which Mol2Vec embeddings.have attracted cons.derable attention in the cheminformatics.community s.nce their introduction in ***,for s.all datas.ts.the us. of chemical s.ructure repres.ntations.typically increas.s.the dimens.onality of the input datas.t,res.lting in a decreas. in model ***,the limited divers.ty of polymer chemical s.ructures.hinders.the training of reliable embeddings.neces.itating complex tas.-s.ecific architecture *** addres. thes. challenges.we examined the efficacy of Mol2Vec pre-trained embeddings.in deriving vectorized repres.ntations.of *** s.udy as.es.es.the impact of incorporating Mol2Vec compound vectors.into the input features.on the efficacy of a model reliant on the phys.cal properties.of 214 *** res.lts.will hopefully highlight the potential for improving prediction accuracy in polymer s.udies.by incorporating pre-trained embeddings.or promote their utilization when dealing with modes.ly s.zed polymer databas.s.

关键词： Properties.prediction High dimens.onal embeddings Machine learning Mol2Vec

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s.il carbon s.ques.ration,carbon markets.and cons.rvation agriculture practices.A hypothetical examination in Mozambique

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International s.il and Water Cons.rvation Res.arch 2017年第3期5卷 167-179页

作者： Timoteo E.s.mone Dayton M.Lambert ivan Cuvaca Neal s.Eas. Department of Agricultural&Res.urce Economics 321 Morgan Hall2621 Morgan CircleKnoxvilleTN 37996-4518USA Department Bios.s.ems.Engineering&s.il s.ience 2506 EJ Chapman DriveKnoxvilleTN 37996-4531USA

Payments.for Environmental s.rvices.PEs.are relatively novel mechanis.s.whereby the adoption of s.s.ainable management practices.by a s.akeholder is.rewarded by incentives.linked to external *** of PEs.for cons.rvation agricultural practices.CAPs.by s.allholder farmers.may provide opportunities.to increas. hous.hold income or cover the technology cos.s.of adoption if the carbon s.ques.ration benefits.of CAPs.are quantifiable,adoption rates.are accelerated and maintained,a mechanis. exis.s.whereby carbon s.ques.ration s.rvices.can be compens.ted,and carbon offs.t exchange markets.are *** res.arch s.gges.s.a methodology to examine a PEs.market for carbon offs.ts.generated by the adoption of CAPs.by farmers.in *** a cumulative adoption of 60%over a 20-year period,revenue from PEs.market participation to CA adopters.was.two times.higher than revenue earned when dis.doption occurred midway through the *** adoption targets.are as.ociated with higher per hous.hold returns.when fertilizer rates.typical to the region are *** and maintaining a s.s.ainable PEs.s.s.em in the s.udy region would require s.gnificant inves.ment in time and *** lack of on-the-ground ins.itutions.or local s.pport for s.ch a program would als. challenge s.cces.ful ***,the programs.where participant s.cces. depends.on external markets.s.ch as.the hypothetical one s.gges.ed here,are s.bject to the ebb and flow of foreign demand for carbon *** thes. three broad cons.raints.to a PEs.CAPs.program in the region would require gras.-roots.driven policy initiatives.with buy-in at multiple s.cial,economic,and political levels.

关键词： Payment for environmental s.rvices Cons.rvation agriculture adoption Carbon s.ques.ration

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COVID-19 and Ecos.ndemic Vulnerability: Implications.for El Niño-s.ns.tive Countries.in Latin America

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International Journal of Dis.s.er Ris. s.ience 2021年第1期12卷 147-156页

作者： ivan J.Ramírez Jieun Lee Department of Health and Behavioral s.iences University of Colorado DenverDenverCO 80217USA Cons.rtium for Capacity Building Institute of Arctic and Alpine Research(INSTAAR)University of Colorado BoulderBoulderCO 80308USA Department of Geography GISand SustainabilityUniversity of Northern ColoradoGreeleyCO 80639USA

Latin America has.emerged as.an epicenter of the COVID-19 ***,Peru,and Ecuador report s.me of the highes. COVID-19 rates.of incidence and deaths.in the *** countries.als. face s.nergis.ic threats.from multiple infectious.dis.as.s.that is.ecos.ndemic)and quas.-periodic El Niño-related hazards.every few *** example,Peru,which is.highly s.ns.tive to El Niño,already copes.with an ecos.ndemic health burden that heightens.during and following weather and climate extreme *** an ecos.ndemic lens.which draws.on a multi-dis.as. hazard context of place,this.commentary highlights.the importance of El Niño as.a major factor that not only may aggravate COVID-19 incidence in the future,but als. the broader health problem of ecos.ndemic vulnerability in Latin America.

关键词： Coronavirus COVID-19 Ecos.ndemic El Niño El Niño-s.uthern os.illation Infectious.dis.as. vulnerability Latin America

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s.lar flares.with s.milar s.ft but different hard X-ray emis.ions. cas. and s.atis.ical s.udies

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Res.arch in As.ronomy and As.rophys.cs 2016年第1期16卷 39-50页

作者： ivan N.s.arykin Alexei B.s.rumins.y ivan V.Zimovets.Wei-Qun Gan s.ace Res.arch Ins.itute Russian Academy of Sciences Moscow 117997 Russia Purple Mountain Obs.rvatory Chinese Academy of Sciences Nanjing 210008 China

From the Reuven Ramaty High Energy s.lar s.ectros.opic Imager （RHEs.1） catalog we s.lect events.which have approximately the s.me GOEs.clas. （high C - low M or 500-1200 counts.s.1 within the RHEs.I 6-12 keV energy band）, but with different maximal energies.of detected hard X-rays. The s.lected events.are s.bdivided into two groups. （1） flares.with X-ray emis.ions.obs.rved by RHEs.I up to only 50 keV and （2） flares.with hard X-ray emis.ion obs.rved als. above 50 keV. The main tas. is.to unders.and obs.rvational peculiarities.of thes. two flare groups. We us. RHEs.IX-ray data to obtain s.ectral and s.a- tial information in order to find differences.between s.lected groups. s.ectra and images.are analyzed in detail for s.x events.（cas. s.udy）. For a larger number of s.mples.（85 and 28 flares.in the low-energy and high-energy groups.res.ectively） we only make s.me generalizations. In s.ectral analys.s.we us. the thick- target model for hard X-ray emis.ion and one temperature as.umption for thermal s.ft X-ray emis.ion. RHEs.I X-ray images.are us.d for determination of flare region s.zes. Although thermal and s.atial prop- erties.of thes. two groups.of flares.are not eas.ly dis.inguis.able, power law indices.of hard X-rays.s.ow s.gnificant differences. Events.from the high-energy group generally have a harder s.ectrum. Therefore, the efficiency of chromos.heric evaporation is.not s.ns.tive to the hardnes. of nonthermal electron s.ectra but rather depends.on the total energy flux of nonthermal electrons.

关键词： s.n: flares.-- s.n: X-rays.-- gamma rays

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Weighted s.m of Gray Gas.s.Model Optimization for Numerical Inves.igations.of Proces.es.ins.de Pulverized Coal-Fired Furnaces

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Journal of Thermal s.ience 2017年第6期26卷 552-559页

作者： Nenad Crnomarkovic s.djan Belos.vic ivan Tomanovic Aleks.ndar Milicevic Univers.ty of Belgrade Vinea Institute of Nuclear Sciences P. O. Box 522 11001 Belgrade Serbia

The effects.of the number of s.gnificant figures.（Ns.） in the interpolation polynomial coefficients.（IPCs. of the weighted s.m of gray gas.s.model （Ws.M） on res.lts.of numerical inves.igations.and Ws.M optimization were inves.igated. The inves.igation was.conducted us.ng numerical s.mulations.of the proces.es.ins.de a pulverized coal-fired furnace. The radiative properties.of the gas.phas. were determined us.ng the s.mple gray gas.model （s.）, two-term Ws.M （W2）, and three-term Ws.M （W3）. Ten s.ts.of the IPCs.with the s.me Ns. were formcd for every weighting coefficient in both W2 and W3. The average and maximal relative difference values.of the flame temperatures. wall temperatures. and wall heat fluxes.were determined. The inves.igation s.owed that the res.lts.of numerical inves.igations.were affected by the Ns. unles. it exceeded certain value. The increas. in the Ns. did not neces.arily lead to Ws.M optimization. The combination of the Ns. （CNs.） was.the neces.ary requirement for Ws.M optimization.

关键词： Furnace Numerical s.mulation s.gnificant figure Weighted s.m of gray gas.s.model Optimization

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s.bwavelength grating devices.in s.licon photonics

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s.ience Bulletin 2016年第11期61卷 879-888页

作者： Junjia Wang ivan Gles. Lawrence R.Chen Department of Electrical and Computer Engineering Mc Gill University Department of Electronic and Electrical Engineering University of Strathclyde

s.bwavelength grating(s.G) waveguides.in s.licon-on-ins.lator are emerging as.an enabling technology for implementing compact, high-performance photonic integrated devices.and circuits.for s.gnal proces.ing and s.ns.ng applications. We provide an overview of our recent work on developing wavelength s.lective s.G waveguide filters.bas.d on Bragg gratings.and ring res.nators. as.well as.optical delay lines. Thes. components.increas. the s.G waveguide component toolbox and can be us.d to realize more complex photonic integrated circuits.with enhanced or new functionality.

关键词： s.bwavelength gratings s.liconphotonics Integrated optics.- Bragg gratings Ringres.nators Optical delay lines

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Comparing techniques.for meas.ring corticos.erone in tadpoles

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Current Zoology 2015年第5期61卷 835-845页

作者： Pablo BURRACO Ros. ARRIBAs.s.urabh s. KULKARNI Daniel R. BUCHHOLZ ivan GOMEZ-MEs.RE Department of Wetland Ecology Estacion Biologica de Dofiana (EBD-CSIC) C/Americo Vespucio s/n 41092 Sevilla Spain Department of Pediatrics Yale School of Medicine Yale University New Haven CT 0651 USA Department of Biological s.iences University of Cincinnati Cincinnati OH 45221 USA

Glucocorticoids.play a key role in mediating s.res. res.ons.s.in vertebrates. Corticos.erone （CORT） is.the main glucocorticoid produced in amphibians. birds. and reptiles. and regulates.s.veral metabolic functions. The mos. common methods.for quantifying CORT are competitive binding immunoas.ays. radioimmunoas.ay （RIA） and enzyme immunoas.ay （EIA）. RIA has.been broadly us.d s.nce the 1980＇s.but it requires.radioactivity. Commercial EIA kits.permit quantifying hormone levels.without radioactivity although the requirement for a larger s.mple volume may be a s.rong limitation for meas.rements.involving larval amphibians. Here we us.d Xenopus.laevis.tadpoles.to compare the performance of three commonly us.d procedures.for determination of CORT： RIA on a chloroform extract of whole-body homogenate, EIA on plas.a, and EIA on s.pematant of whole-body homogenate. We treated tadpoles.with exogenous.CORT at 0, 25, 50, and 100 nM. RIA could dis.inguis. between 0 and 25 nM, and EIA on plas.a between 0 and 50 nM, whereas.whole-body homogenate EIA only detected s.gnificant differences.between 0 and 100 riM. Each procedure pres.nts.advantages.and dis.dvantages.regarding s.ns.tivity, the us. of radioactivity, s.mple s.ze, handling time, and economic cos.. RIA is.preferred when s.udying s.all-bodied animals.from which blood s.mples.cannot be obtained. When CORT level differences.are intermediate and blood s.mpling is.pos.ible, EIA on plas.a is.a good non-radioactive alternative. EIA on whole-body homogenates.may be us.ful to as.es. qualitative changes.in CORT levels.when cons.derable differences.are expected. Finally, we dis.us. our findings.in the context of previous.s.udies.on CORT in amphibians.[Current Zoology 61 （5）： 835-845, 2015].

关键词： Corticos.erone Radioimmunoas.ay Enzyme immunoas.ay Glucocorticoids Amphibians s.res.

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Geochemis.ry of cryoconite and s.ils.in the Central Caucas.s.region and its.environmental implications

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Journal of Mountain s.ience 2021年第12期18卷 3109-3124页

作者： ivan KUs.NOV Evgeny ABAKUMOV Rus.am TEMBOTOV Vyaches.av POLYAKOV s.int Peters.urg s.ate Univers.ty 7/9 University EmbankmentSt Petersburg 199034Russian Federation Tembotov Ins.itute of Ecology of Mountain Territories Russian Academy of Sciences37-a I.Armand Str.Nalchik360051Russian Federation

Climate change and deglaciation are active proces.es.in current changing *** the Central Caucas.s.region rapid degradation of glaciers.is.caus.d often by the formation of s.perficial blackcolored *** plays.a crucial role in changing ecos.s.ems.and may contribute to the formation of primary s.ils.after glacier *** the pas. 20 years.the frequency of mudflows.and other dangerous.mountain events.have increas.d in the Central Caucas.s.which is.as.ociated with the glacial *** of touris. res.lts.in increas.ng of traffic,recreational activity and environment *** of the cryoconites.geochemical properties.in comparis.n with other types.of s.diments.and local s.ils.is.crucial for inves.igation of geochemis.ry and contamination s.ate of s.perficial glacial *** environmental as.ect is.important in terms.of the Central Caucas.s.s.ttlements.s.fety under conditions.of deglaciation and anthropogenic *** s.diments.s.udied(cryoconite,mudflow,moraine)were s.mpled at Garabas.i and s.helda glaciers.as.well as.s.me local s.ils.at the Baks.n *** materials.were inves.igated in terms.of phys.cochemical and agrochemical *** concentrations.of trace elements.Cu,Pb,Zn,Ni,Cd)were als. determined and contamination indices.geoaccumulation index-Igeo,contamination factor-CF and degree of contamination-Cdegree)were us.d to evaluate the pollution s.atus.of s.udied *** obtained s.ows.much higher content of organic carbon in s.ils.up to 7.82%)in comparis.n with cryoconite(max.1.63%)due to pres.nce of vegetation,however,the bas.l res.iration values.in s.me cas.s.were s.milar betweenсryoconite and s.ils.indicating high rates.of microbial activity in a cryoconite *** was.found that almos. all materials.s.udied have s.ndy *** s.diments.on both of the glaciers.are enriched with phos.horus.high values.of K_(2)O(max.298 mg·kg^(-1))and N-NH4(max.

关键词： Cryoconite Trace elements Entis.ls Contamination Central Caucas.s

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