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A Model of Irregular Impurity at the Surface of Nanoparticle and Catalytic Activity

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Communications in Theoretical Physics 2012年第7期58卷 55-58页

作者： I.v.Blinova v.v.Gusarov I.Yu.Popov St.Petersburg National Research University of Information Technologies Mechanics and OpticsKronverkskiy49St.Petersburg 197101Russia St.Petersburg State Technological Institute (Technical University) Moskovskiy26St.Petersburg 190013Russia

A problem of nanocatalyst improvement is considered. The existence of irregularities at the surface of nanoparticle leads to the increasing of the surface/volume ratio and, correspondingly, to the improvement of the catalytic activity. But this impurity gives one an additional effect due to the change of the electronic density at the surface. We suggest simple model for the description of this effect. The model allows one to find the discrete spectrum of the Schrdinger operator for nanoparticle. Due to this impurity induced bound states the electron density increases near the surface. It leads to the increase of the catalytic activity of nanoparticles with surface impurities.

关键词： semi-infinite crystal operator spectrum impurity catalytic activity nanoparticle

Dynamics of acousto-rheological properties of polymerized materials on their solidification

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Rare Metals 2007年第S1期26卷 1-4页

作者： RIMLYAND v I BAKHANTSOv A v STARIKOvA v N Physics Department Automation of Physical and Technical Measurements LaboratoryPacific National University

An automated system was designed to study in a continuous regime the rheological properties of the care polymeric compositions using the damped vibration *** a parallel mode measurements of rheological and acoustic characteristics of the care compositions were made on the basis of epoxy *** of shear modulus,viscosity,the sound speed,and the damping coefficient as functions of polymerization were *** of spectral characteristics of acoustic signals in the polymerization were *** of the experimental results obtained reveals that the dynamics of the variation of acoustic and rheological properties is significantly *** major change of acoustic characteristics occurs in the initial stage of the solid state formation when a transition from a liquid-to-gel like state takes *** characteristics vary dramatically at the crossover from a high-viscosity to solid *** the frequency dependencies of an acoustic signal a number of essential features were observed.

关键词： viscosity acoustic properties shear modulus polymerization composition

Investigation of thermal evolution of nanodomain structures in nonlinear barium sodium niobate crystals

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Chinese Optics Letters 2008年第2期6卷 143-145页

作者： S.v.Ivanova P.N.Lebedev Physical Institute of RAS Leninsky pr.53 Moscow 119991Russia

By the 90° elastic light scattering investigation and far field observation in the range of 20 - 800 ℃, the relation between behavior of light scattering anomalies and evolution of nanodomain structures in lattice of barium sodium niobate （Ba2NaNb5O15, BSN） crystal was clarified. The correlation between anomalies on the temperature curves of the elastic light scattering intensity and temperature transformations of nanodomains was studied by X-ray and electron microscope methods. Phase transition near 500 ℃ and movement in field of scattering light could be explained by appearance of a new incommensurate phase.

关键词： Elastic scattering Light fields Light intensity Light scattering Transmission electron microscopy X ray microscopy

Kuedinskie Kluchiki, a Unique Middle Permian Biota Locality as a Key-point for Reconstruction of Late Paleozoic Terrestrial Ecosystems of the Urals, Russia

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Acta Geologica Sinica(English Edition) 2024年第4期98卷 850-866页

作者： Serge v.NAUGOLNYKH Geological Institute of Russian Academy of Sciences Pyzhevsky per.7119017 MoscowRussia

Field work focused on the Kuedinskie Kluchiki locality, Perm region, Urals, Russia, which contains a rich assemblage of diverse fossil organisms including higher plants(equisetophytes, pteridosperms, ginkgophytes, conifers, vojnovskyans) represented by stems, leaves and reproductive organs;invertebrates(mollusks, arthropods), and tetrapods(temnospondyl amphibians, seymouriamorphs, cotylosaurs, synapsids, diapsids), as well as bony fishes. General characteristics of the taxonomical composition of the Kuedinskie Kluchiki locality are given. A new peltaspermalean pteridosperm taxon, Compsopteris longipinnata sp. nov., and a voltzialean conifer Archaeovoltzia kuedensis sp. nov. are described. General considerations on the paleoecologic and paleogeographic conditions of the Kuedinskie Kluchiki locality origin are given.

关键词： paleobotany paleoecology taxonomy Lagerst?tten new taxa peltasperms conifers Wordian Cis-Urals

Boosting propane dehydrogenation by gallium hydride species formed in situ

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Science China Chemistry 2024年第6期67卷 1753-1755页

作者： Evgenii v.Kondratenko Leibniz-Institut für Katalyse e.v. Albert-Einstein-Str.29aRostock18059Germany

An inspiring paper recently published in Nature Chemistry[1]by the group of *** Gong at Tianjin University is the motivation for this highlight *** reported results show that the understanding of reaction-induced restructuring of heterogeneous catalysts is of great importance for their targeted development because usually unstable compounds can be formed and stabilized under reaction conditions.

关键词： conditions hydride stabilized

Women Entrepreneurship Index Prediction Model with Automated Statistical Analysis

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Intelligent Automation & Soft Computing 2023年第5期36卷 1797-1810页

作者： v.Saikumari v.Sunitha Department of Management Studies Easwari Engineering CollegeRamapuram600089India

Recently,gender equality and women’s entrepreneurship have gained considerable attention in global economic *** to the design of any policy interventions to increase women’s entrepreneurship,it is signiﬁcant to comprehend the factors motivating women to become *** non-understanding of the factors can result in the endurance of low living stan-dards and the design of expensive and ineffectual *** female involve-ment in entrepreneurship becomes higher in developing economies compared to developed *** Entrepreneurship Index(WEI)plays a vital role in determining the factors that enable theﬂourishment of high potential female entrepreneurs which enhances economic welfare and contributes to the economic and social fabric of ***,it is needed to design an automated and accurate WEI prediction model to improve women’s *** this view,this article develops an automated statistical analysis enabled WEI predic-tive(ASA-WEIP)*** proposed ASA-WEIP technique aims to effectually determine the *** proposed ASA-WEIP technique encompasses a series of sub-processes such as pre-processing,WEI prediction,and parameter *** the prediction of WEI,the ASA-WEIP technique makes use of the Deep Belief Network(DBN)model,and the parameter optimization process takes place using Squirrel Search Algorithm(SSA).The performance validation of the ASA-WEIP technique was executed using the benchmark dataset from the Kaggle *** experimental outcomes stated the better outcomes of the ASA-WEIP technique over the other existing techniques.

关键词： Predictive model women entrepreneurship statistical models gender equality decision making work-life balance learning and development

Cosmology with an Effective Λ-Term in Lyra Manifold

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Chinese Physics Letters 2013年第11期30卷 215-219页

作者： v.K.Shchigolev Department of Theoretical Physics Ulyanovsk State UniversityUlyanovsk 432000Russia

A cosmological model in Lyra's geometry is studied under the assumption that an effective cosmological term appears in the field equations as the result of interaction between the displacement vector field and an auxiliaryΛ*** exact solutions to the model equations are obtained and preliminarily studied for the simplest cases in order to illustrate how such a model works.

关键词： equations exact auxiliary

A radical reinterpretation of the growth and form of the stromatolite Conophyton lituus(Maslov)from evidence of syngenetic biofilm mineralisation

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Journal of Palaeogeography 2022年第1期11卷 69-84页

作者： Robert v.Burne Research School of Earth Sciences The Australian National University CanberraACT 0200Australia School of Earth and Environmental Sciences The University of QueenslandBrisbaneQLD 4072Australia

Conophyton(Maslov)is a cylindroidal stromatolite form-genus characterized by nested conical ***-preserved Conophyton,up to 4 m tall and with basal diameters of up to 50 cm,are exposed in the Proterozoic Atar Formation of Mauritania,where many occur together,in growth position,as fields of individual columns spaced between 5 and 70 cm *** uniformity of these forms and their regular distribution suggest that they grew in quiet-water environments below wave *** for their penecontemporaneous organomineralization is indicated by nearby toppled examples of undeformed Conophyton forms alongside eroded lithified Conophyton fragments in carbonate *** characteristics of Conophyton have been used to classify the structures-the form of the lamination and the nature of its axial structure.A mathematical/physical model provides an explanation for the growth pattern of *** predicts that coniform structures with thickened axial zones form when upward organic growth of a biofilm moderately exceeds the rate of its *** varying characteristics of these features between different forms of Conophyton are thought to reflect biomineralization of the decaying biofilm rather than differences in the composition of microbial communities.A modern example of a syngenetic mineralization process capable of producing similar structures has been observed in the contemporary sediments of Lake Preston,Western Australia,where benthic microbial mats are being transformed into coniform lithified *** initial biomineralization of the coniform mat forms magnesium silicate that first coats and permineralizes web-like microbial extracellular polymeric substances(EPS)and then coalesces into a uniform mass that provides mechanical strength to the *** a later stage,massive carbonate crystal growth occurs that over-prints much of this texture,leaving only small,remnant areas of the magnesium silicate *** fossil Conophyton are composed o

关键词： Conophyton Morphogenesis Proterozoic Stromatolite Microbialite Mineralisation Biofilm Lake Clifton Lake Preston Maslov

Solar photocatalytic pathogenic disinfection:Fundamentals to state-of-the-art

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Water Science and Engineering 2023年第2期16卷 132-142页

作者： Leena v.Bora Department of Chemical Engineering Institute of TechnologyNirma UniversitySarkhej-Gandhinagar HighwayAhmedabad 382481India

It is necessary to treat pathogen-infected water before its *** conventionally used treatment methods,solar photocatalysis has gained considerable momentum owing to its operational simplicity and capacity to use freely and abundantly available solar *** article systematically reviewed the disinfection of water with *** addressed the concerns of microbial infection of water and the fundamentals behind its treatment with *** presented an in-depth description of pathogenic deactivation with powerful reactive oxygen *** emphasis was given to process intensification as it is an attractive technique that provides multifunctionality and/or equipment *** reactor design regarding mobilised/immobilised photocatalysts and compound parabolic concentrators were ***,key parameters governing photoperformance,corresponding trade-offs,and the need for their optimisation were ***,this article is a single point of reference for researchers,environmentalists,and industrialists who address the ever-severing challenge of providing clean water whilst also maintaining energy sustainability.

关键词： Water Solar light Photocatalysis Pathogen E.coli Intensification Photoreactor Disinfection