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Journal of Analysis and Testing 2023年第4期7卷 435-443页

作者： Valeriia Maksimova Varvara Lapina Leonid Martynov andrey Shishov Olga Mokhodoeva Vernadsky Institute of Geochemistry and Analytical Chemistry Russian Academy of SciencesMoscow 119991Russian Federation Lomonosov Institute of Fine Chemical Technologies MIREA-Russian Technological UniversityMoscow 119454Russian Federation Department of Analytical Chemistry Institute of ChemistrySaint-Petersburg State UniversitySt.Petersburg 199034Russian Federation

A novel analytical procedure for the determination of gold by electrothermal atomic absorption spectrometry combined with selective liquid-liquid extraction by natural deep eutectic solvents(NADESs)is *** extraction ability of the NADESs prepared using menthol,thymol and camphor toward gold in hydrochloric acid solutions was *** extraction efficiency was improved by optimizing the parameters including the composition of the NADES s,the volume ratio of organic and aqueous phases,kinetics,and acidity of the *** determination of gold was carried out by electrothermal atomic absorption spectrometry directly in the NADES s phase dissolved in isopropyl *** extraction recovery of gold from 1 mol/L HCl with the NADESs based on menthol and camphor mixed in a molar ratio 1:1 was 99.7%at an enrichment factor of *** limits of detection and quantification of the proposed procedure were 1μg/L and 3.3μg/L,respectively,with a relative standard deviation of less than 5%.The developed procedure was applied for determination of gold in the certified reference material of ore,environmental and waste waters.

关键词： Gold Liquid-liquid extraction Menthol/camphor Natural deep eutectic solvents(NADESs) Electrothermal atomic absorption spectrometry(ETAAS)

SnSi nanocrystals of zinc-blende structure in a Si matrix

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Nano Research 2015年第12期8卷 3905-3911页

作者： Alexander Tonkikht andrey Klavsyuk Nikolay Zakharov Alexander Saletsky Peter Werner Max Planck Institute of Microstructure Physics Halle(Saale) 06120 Germany Faculty of Physics Moscow State University Moscow 119991 Russian Federation

A zinc-blende （sphalerite） crystallographic structure of SnSi nanocrystals generated by molecular-beam epitaxy is observed by electron microscopy techniques in a Si matrix. Ab initio density-functional modeling reveals a stabilizing effect of the Si matrix, which results in the lowest formation enthalpy of SnSi nanocrystals having the unexpected zinc-blende structure. Such nanocrystals could be applied in Si photonics to function as non-centrosymmetric media for the nonlinear optical process of second harmonic generation.

关键词： epitaxy density functional theory zinc-blende Si-Sn alloy

Polarity,intramolecular charge transfer,and hydrogen bond comediated solvent effects on the optical properties of graphene quantum dots

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Nano Research 2023年第1期16卷 45-52页

作者： Yalei Hu Christof Neumann Lena Scholtz andrey Turchanin Ute Resch-Genger Siegfried Eigler Institute of Chemistry and Biochemistry Freie Universität BerlinTakustraße 314195 BerlinGermany Institute of Physical Chemistry and Abbe Center of Photonics Friedrich Schiller University JenaLessingstraße 1007743 JenaGermany Federal Institute for Materials Research and Testing(BAM) Division BiophotonicsRichard Willstätter Straße 1112489 BerlinGermany

Graphene quantum dots(GQDs)have attracted increasing attention due to their favorable optical properties and have been widely used,e.g.,in the biomedical ***,the properties related to the chemical structure of GQDs,resulting in solventdependent optical properties,still remain ***,we present the synthesis of long-wavelength emitting GQDs with a size of about 3.6 nm via a solvothermal method using oxo-functionalized graphene(oxo-G)and p-phenylenediamine as precursors and their structural and surface chemical analysis by transmission electron and atomic force microscopy(TEM;AFM)as well as Fourier-transform infrared,Raman,and X-ray photoelectron spectroscopy(FTIR;Raman;XPS).Subsequently,the influence of solvent polarity and proticity on the optical properties of the as-prepared GQDs bearing–OH,–NH_(2),–COOH and pyridine surface groups was *** on the results of the absorption and fluorescence(FL)studies,a possible luminescence mechanism is *** observed solvent-induced changes in the spectral position of the FL maximum,FL quantum yield,and FL decay kinetics in protic and aprotic solvents of low and high polarity are ascribed to a combination of polarity effects,intramolecular charge transfer(ICT)processes,and hydrogen ***,the potential of GQDs for the optical sensing of trace amount of water was *** results of our systematic spectroscopic study will promote the rational design of GQDs and shed more light on the FL mechanism of carbon-based fluorescent nanomaterials.

关键词： graphene quantum dots(GQDs) polarity intramolecular charge transfer(ICT) hydrogen bond optical properties

Basal metabolic rate in free-living tropical birds： the influence of phylogenetic, behavioral, and ecological factors

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Current Zoology 2018年第1期64卷 33-43页

作者： andrey BUSHUEV Oleg TOLSTENKOV Ekaterina ZUBKOVA Eugenia SOLOVYEVA Anvar KERIMOV Department of Vertebrate Zoology Faculty of Biology Lomonosov Moscow State University Leninskie Gory 1/12 Moscow 119234 Russia Joint Russian-Vietnamese Tropical Research and Technological Center South Branch Street 3/2 3 10 District Ho Chi Minh City Vietnam Laboratory of Experimental Parasitology Center of Parasitology A.N. Severtsov Institute of Ecology and Evolution Russian Academy of Sciences Leninskij prospekt 33 Moscow 119071 Russia Zoological Museum of Lomonosov Moscow State University Bolshaya Nikitskaya B Moscow 125009 Russia

The majority of our knowledge of avian energetics is based on studies of birds from temperate and high latitudes. Using the largest existing sample of wild-caught Old World tropical species, we showed that birds from Southern Vietnam had lower basal metabolic rate （BMR） than temperate species. The strongest dissimilarity between tropical and temperate species was the low scaling exponent in the allometric relation between BMR and body mass in tropical birds （the regression slope was 0.573）. The passerine migrants to temperate and high latitudes had higher BMR than tropical sedentary passerines. Body mass alone accounted for 93% of the variation in BMR （body mass ranged from 5 to 252 g）. Contrary to some other studies, we did not find evidence besides the above mentioned that phylogeny, taxonomy, behavior, or ecology have a significant influence on BMR variation among tropical birds.

关键词： allometry BMR body mass energy metabolism tropical birds.

Diversity and Adaptations of Immature Diptera in Semiaquatic Habitats at Shorelines of Hypersaline Lakes in the Crimea,with a Brief Review of Diptera in Mineralized Bodies of Water

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Acta Geologica Sinica(English Edition) 2014年第S1期88卷 98-100页

作者： andrey PRZHIBORO Zoological Institute Russian Academy of SciencesSt.

The order Diptera(Insecta)is one of animal groups most successful in the colonization of mineralized shallow aquatic and semiaquatic *** the same time,the taxonomic composition of Diptera,their role in

关键词： salt lakes mineralized bodies of water aquatic habitats shoreline semiaquatic habitats Diptera larvae biodiversity community taxonomic richness adaptations heat shock proteins.

两步法制备纳米TiC_(p)/GH3536复合粉末组织性能研究

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材料工程 2024年第8期52卷 189-199页

作者：刘佳伟宋美慧李岩张煜李艳春张晓臣安德烈·萨莫欣杨慧敏黑龙江省科学院高技术研究院哈尔滨150009 俄罗斯科学院冶金与材料研究所莫斯科119991 黑龙江工程学院材料与化学工程学院哈尔滨150050

采用机械合金化(mechanical alloying, MA)结合热等离子体球化处理(thermal plasma spheroidization,TPS)两步法,制备纳米TiC_(p)/GH3536复合粉末。采用霍尔流速计、斯科特容量计、XRD、粒度粒形仪、扫描电子显微镜及透射电子显微镜等... 详细信息

采用机械合金化(mechanical alloying, MA)结合热等离子体球化处理(thermal plasma spheroidization,TPS)两步法,制备纳米TiC_(p)/GH3536复合粉末。采用霍尔流速计、斯科特容量计、XRD、粒度粒形仪、扫描电子显微镜及透射电子显微镜等分析测试手段,研究球化处理前后复合粉末的流动性、松装密度、粒度分布、球形度及微观组织形貌。结果表明:第一步MA-5 h处理得到的预制粉末为基体GH3536表面非均匀附着纳米TiC颗粒的不规则形状粉末;相比原始GH3536粉末,预制粉末内部等轴晶数量增多,晶粒得到细化,但流动性和松装密度均降低。第二步TPS处理得到的纳米TiC_p/GH3536复合粉末为球形,原始不规则纳米TiC颗粒被球化,同时均匀分布于GH3536基体内部;去除平均粒度183.27 nm的亚微米颗粒后,复合粉末的流动性、松装密度和球形度得到进一步改善。亚微米颗粒的TEM结果显示,纳米级GH3536微球上均匀包覆着一层TiC,类似核壳结构,且粉末中出现球状TiC颗粒。两步法制备的纳米TiC_(p)/GH3536复合粉末,平均球形度达0.965,平均粒径为33.65μm,流动性为17.1 s/50 g,松装密度为4.184 g/cm^(3)。

关键词：热等离子体球化纳米TiC_p/GH3536 复合材料微观组织性能

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Effective properties of a porous inhomogeneously polarized by direction piezoceramic material with full metalized pore boundaries:finite element analysis

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Journal of Advanced Dielectrics 2020年第5期10卷 1-10页

作者： andrey Nasedkin Mohamed Elsayed Nassar Institnute of Mathematics Mechanics and Computer Science Southem Federal University Miltchakova Street 8aRostov on Don 344090Russia Department of Physics and Engineering Mathematics Faculty of Electronic Engineering Menoufia University 32952 MenoufEgypt

This paper concerns the homogenization problems for porous piezocomposites with infinitely thin metalized pore *** determine the effective properties,we used the effective moduli method and the finite element approaches,realized in the ANSYS *** a simple model of the representative volume,we applied a unit cell of porous piezoceramic material in the form of a cube with one spherical *** modeled metallization by introducing an additional layer of material with very large permittivity coefficients along the pore *** we simulated the nonuniform polarization field around the *** taking this effect into account,we previously solved the electrostatic problem for a porous dielectric material with the same geometric *** this problem,we obtained the polarization field in the porous piezomaterial;after that,we modified the material properties of the finite elements from dielectric to piezoelectric with element coordinate systems whose corresponding axes rotated along the polarization *** a result,we obtained the porous unit cell of an inhomogeneously polarized piezoceramic *** the solutions of these homogenization problems,we observed that the examined porous piezoceramics composite with metalized pore boundaries has more extensive effective transverse and shear piezomoduli,and effective dielectric constants compared to the conventional porous *** analysis also showed that the effect of the polarization field inhomogeneity is insignificant on the ordinary porous piezoceramics;however,it is more significant on the porous piezoceramics with metalized pore surfaces.

关键词： Piezoelectricity porous piezoceranics metalized micropore nonuniform polarization transverse piezoelectic modulus homogerization problem effective modulus finite element method

Impacts of late Quaternary environmental change on the long-tailed ground squirrel(Urocitellus undulatus)in Mongolia

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Zoological Research 2018年第5期39卷 364-372页

作者： Bryan S.McLean Batsaikhan Nyamsuren andrey Tchabovsky Joseph A.Cook University of Florida Florida Museum of Natural History Department of Biology School of Arts and Sciences National University of Mongolia Laboratory of Population Ecology A.N. Severtsov Institute of Ecology and Evolution University of New Mexico Department of Biology and Museum of Southwestern Biology

Impacts of Quaternary environmental changes on mammal faunas of central Asia remain poorly understood due to a lack of comprehensive phylogeographic sampling for most *** help address this knowledge gap,we conducted the most extensive molecular analysis to date of the long-tailed ground squirrel （Urocitellus undulatus Pallas 1778） in Mongolia,a country that comprises the southern core of this species＇ *** on material from recent collaborative field expeditions,we genotyped 128 individuals at two mitochondrial genes （cytochrome b and cytochrome oxidase Ⅰ;1797 bp total）.Phylogenetic inference supports the existence of two deeply divergent infraspecific lineages （corresponding to subspecies *** and ***）,a result in agreement with previous molecular investigations but discordant with patterns of range-wide craniometric and external phenotypic *** the widespread western eversmanni lineage,we recovered geographically-associated clades from the：（a） Khangai,（b） Mongolian Altai,and （c） Govi Altai mountain *** structure in *** is consistent with an isolation-by-distance model;however,genetic distances are significantly lower than among subspecies,and intra-clade relationships are largely *** latter patterns,as well as the relatively higher nucleotide polymorphism of populations from the Great Lakes Depression of northwestern Mongolia,suggest a history of range shifts into these lowland areas in response to Pleistocene glaciation and environmental change,followed by upslope movements and mitochondrial lineage sorting with Holocene *** study illuminates possible historical mechanisms responsible for *** genetic structure and contributes to a framework for ongoing exploration of mammalian response to past and present climate change in central Asia.

关键词： Central Asia Gobi Desert Great LakesDepression Mongolia Phylogeography

Substituted diamides of dipicolinic acid as extractants and ionophores for rare earth metals

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Journal of Rare Earths 2023年第8期41卷 1234-1241,I0005页

作者： Yingchao Ren Valery A.Polukeev Ekaterina V.Kenf Liudmila I.Tkachenko Mikhail Yu Alyapyshev Vasily A.Babain andrey V.Nechaev andrey V.Legin Dmitry O.Kirsanov Institute of Chemistry Saint-Petersburg UniversityPeterhofUniversitetsky Prospect 26198504Saint-PetersburgRussia JSVC Vekton Ul.2-oy Luch 9192019Saint-PetersburgRussia Khlopin Radium Institute 194021282nd Murinsky avRussia ThreeArc Mining LLC Pr.Narodnogo Opolchenia 10198216Saint-PetersburgRussia Rusredmet Vosstanovleniya str.15bl.3198320St.PeterburgKrasnoe seloRussia

The variety of newly synthesized diamides of dipicolinic acid(DPA)bearing methyl-and oxymethyl substituents in various positions of phenyl ring was investigated as potential ligands for liquid-liquid extraction of rare earth metal ions and as membrane active compounds in plasticized polymeric membranes of potentiometric *** is found that scandium is extracted with 2,6-pyridinedicarboxylic acid diamides similarly to heavy lanthanides,while yttrium is extracted together with light group *** shows high selectivity for the separation of cadmium/zinc,lead/nickel or copper/nickel *** four out of six studied ligands demonstrate significant potentiometric sensitivity towards scandium,yttrium and lanthanides in 10^(-7)-10^(-3)mol/L concentration range in nitric acid *** trends in sensitivity values vary depending on a ligand structure and the highest values are observed for Sc^(3+)and heavy *** to the evaluated selectivity Sm^(3+)is the most preferred ion,while La^(3+)is the most *** differences in sensor behavior in rare earth metal solutions assume that such devices can be applied in sensor arrays for potentiometric analysis of lanthanide mixtures.

关键词： Dipicolini cacid diamides Scandium Yttrium Lanthanides Extraction Potentiometric sensors

Data-driven,client-centric applied behavior analysis treatment-dose optimization improves functional outcomes

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世界儿科杂志:英文版 2023年第8期19卷 753-760页

作者： andrey Ostrovsky Melissa Willa Ted Cho Maxwell Strandberg Sage Howard Colin Davitian Social Innovation Ventures LewesDEUSA Kyo San FranciscoCAUSA UCSF Beniof Children’s Hospital San FranciscoCAUSA SKF Group GöteborgSweden

Background With increasing numbers of individuals diagnosed with autism spectrum disorder(ASD)and with affirmation of applied behavior analysis(ABA)as an evidence-based standard of care for ASD,there has been a proliferation of agencies offering ABA services over the last several *** exists among ABA providers and health plans that reimburse those providers on the optimal number of hours of ABA services that should be *** study aims to understand whether children who receive more hours of ABA therapy achieve better outcomes and to evaluate the impact of the COVID-19-induced shift to telehealth clinical supervision on *** A retrospective cohort analysis was performed using data from the Vineland 3 Comprehensive Interview Form to assess function throughout ABA *** sample t tests,independent sample t tests,Cohen’s D,and Pearson correlations were used to determine relationships between Vineland scores and input variables including hours of service and modality of supervision(in-person ***).Results While statistically and clinically significant improvements in function were observed,children appear to have improved outcomes independent of the number of hours of service *** were also no significant associations between modality of supervision and Vineland standard *** These findings challenge prior research that demonstrated a linear dose–response *** tailoring treatment dosage to the individual client’s needs,providers may be able to better maximize functional progress of the client,to preserve family time,and to utilize health plan dollars more efficiently.

关键词： Autism spectrum disorder(ASD) Autistic disorder Autistic rehabilitation Autistic therapy Telemedicine