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A simple semiempirical model for the static polarizability of electronically excited atoms and molecules

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Chinese Physics B 2023年第4期32卷 290-301页

作者： Alexander s sharipov alexey V Pelevkin Boris I Loukhovitski Central Institute of Aviation Motors Aviamotornaya 2Moscow 111116Russia

We present a semiempirical analytical model for the static polarizability of electronically excited atoms and molecules,which requires very few readily accessible input data,including the ground-state polarizability,elemental composition,ionization potential,and spin multiplicities of excited and ground *** very simple model formulated in a semiclassical framework is based on a number of observed trends in polarizability of electronically excited *** adjust the model,both accurate theoretical predictions and reliable measurements previously reported elsewhere for a broad range of multielectron species in the gas phase are *** some representative compounds of general concern that have not yet attracted sufficient research interest,the results of our multireference second-order perturbation theory calculations are additionally *** show that the model we developed has reasonable(given the considerable uncertainties in the reference data)accuracy in predicting the static polarizability of electronically excited species of arbitrary size and excitation *** findings can be useful for many applications,where there is a need for inexpensive and quick assessments of the static gas-phase polarizability of excited electronic states,in particular,when building the complex nonequilibrium kinetic models to describe the observed optical refractivity(dielectric permittivity)of nonthermal reacting gas flows.

关键词： polarizability electronic excitation semiempirical model quantum chemistry

Influence of polyolefin fibers on the strength and deformability properties of road pavement concrete

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第4期6卷 407-417页

作者： Olga smirnova alexey Kharitonov Yuriy Belentsov Department of Constructing Mining Enterprises and Underground structures Saint-Petersburg Mining UniversitySaint Petersburg 199106Russia Department of Technology of Building Materials and Metrology Saint-Petersburg State University of Architecture and Civil EngineeringSaint Petersburg 190005Russia Department of Building Materials and Technologies Emperor Alexander I St.Petersburg State Transport UniversitySaint Petersburg 190031Russia

Influence of the type and quantity of polyolefin fibers on the strength properties(compression strength, tensile strength in bending, strength in uniaxial tension), the deformation properties(elastic modulus, Poisson’s coefficient) and the abrasion resistance of cement concrete with water-to-cement ratio within 0.31 e0.55 were stated in the *** ways of fibers introduction into fresh concrete were investigated. It was shown that the fibers introduction method and procedure of mixing are the ways to improve the fibers uniform distribution in fresh concrete. The increase of the bending tensile strength and the uniaxial tensile strength of concrete with fibers reinforcement in comparison with the reference concrete was observed with the water-to-cement ratio decrease. The increase of uniaxial tensile strength at age of 28 days for concrete with macrofibers in amount of4.5 kg/m^3 was 23% and 29%;for macrofibers in quantity of 3 kg/m^3 was 19% and 26% with water-cement ratio equal to 0.49 and 0.31, respectively. The maximum reduction of abrasion in the range of 7.5%e10% was observed in concrete with water-to-cement ratio within0.44 e0.55 for all investigated types of fibers. The influence of fibers on the concrete abrasion with lower W/C ratio was negligible. The results can contribute to the rational use of modified polyolefin fibers in road pavement concrete.

关键词： Road pavement concrete Polyolefin fibers strength Elastic modulus Abrasion Water-to-cement ratio

The evolution of eccentricity in the eclipsing binary system As Camelopardalis

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Research in Astronomy and Astrophysics 2018年第1期18卷 113-118页

作者： Valentina Kozyreva Anatoly Kusakin alexey Bogomazov M.V.Lomonosov Moscow state University P.K.Sternberg Astronomical Institute National space Agency Fesenkov Astrophysical Institute

In 2002,2004 and 2017 we conducted high precision CCD photometry observations of the eclipsing binary system As *** analysis of the light curves from 1967 to 2017（our data ＋ data from the literature） we obtained photometric elements of the system and found a change in the system＇s orbital eccentricity of ？e = 0.03 ± *** change can indicate that there is a third companion in the system in a highly inclined orbit with respect to the orbital plane of the central binary,and its gravitational influence may cause the discrepancy between observed and theoretical apsidal motion rates of As Cam.

关键词： binaries:close binaries:eclipsing stars:individual(As Cam)

Evaluation of opening of fractures in the Logovskoye carbonate reservoir, Perm Krai, Russia

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Petroleum Research 2021年第2期6卷 137-143页

作者： Dmitriy A.Martyushev alexey Yurikov Department of Oil and Gas Technologies Perm National Research Polytechnic UniversityPerm614990Russia WA school of Mines:Minerals Energy and Chemical EngineeringCurtin UniversityPerth6151Australia

The development of naturally fractured carbonate reservoirs is extremely challenging. such reservoirshave a dual pore structure consisting of low-permeable matrix with large pore volume and highpermeable fractures constituting main paths for fluid flow. Productivity of wells drilled in such formations tends to decrease rapidly due to the drop in the reservoir pressure and closure of ***, it is crucial to monitor opening of fractures for the effective development of carbonate reservoirs. Three methods for monitoring of opening of fractures including tracer indicators method,Warren and Root method and Victorin’s empirical relation, are applied in the Logovskoye oil reservoir, acarbonate Tournaisian-Famennian formation in Upper Kama Region, Perm Krai, Russia. The threemethods provide reliable estimation of the opening of fractures, which match the reported laboratorydata obtained on thin sections of core samples. The limitations of each method are also discussed. Thetracer indicator method is time-consuming, the Warren and Root method includes hydrodynamic studiesand requires shutdown of wells influencing the oil production, and the application of Victorin’s relationrequires estimation of initial opening and current compressibility of fractures, which can be done usinganalysis of cores or tracer indicators studies. The appropriate method for monitoring of opening offractures should be chosen according to available resources, time, and economic targets of the development project.

关键词： Carbonates Well tests Tracer indicators Warren and Root method Indicator injection

stress dependence of elastic wave dispersion and attenuation in fluid-saturated porous layered media

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science China Earth sciences 2023年第11期66卷 2622-2634页

作者： Fubin CHEN Zhaoyun ZONG Xingyao YIN alexey sTOVAs National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580China Laoshan Laboratory Qingdao 266580China Centre for Exploration Geophysics Curtin UniversityGPO Box U1987PerthWA 6845Australia Department of Geoscience and Petroleum Norwegian University of Science and Technology(NTNU)Trondheim 7031Norway

The fluid-saturated porous layered(FsPL)media widely exist in the Earth's subsurface and their overall mechanical properties,microscopic pore structure and wave propagation characteristics are highly relevant to the in-situ ***,the effect of in-situ stress on wave propagation in FsPL media cannot be well explained with the existing *** fill this gap,we propose the dynamic equations for FsPL media under the effect of in-situ stress based on the theories of poroacoustoelasticity and anisotropic *** loss mechanism is considered to account for the stress-dependent wave dispersion and attenuation induced by global wave-induced fluid ***'s elastic anisotropy parameters are used to represent the anisotropy of the skeleton.A plane-wave analysis is implemented on dynamic equations yields the analytic solutions for fast and slow P waves and two s *** results show that the elastic anisotropy parameters significantly determine the stress dependence of wave *** tortuosity and permeability have remarkable effects on fast and slow P-wave velocity curves and the corresponding attenuation peaks but have little effect on s-wave *** difference in velocities of two s waves occurs when the FsPL medium is subjected to horizontal uniaxial stress,and the s wave along the stress direction has a larger velocity,which implies that the additional anisotropy other than that induced by the beddings appears due to horizontal ***,the predicted velocity results have the reasonable agreement with laboratory *** equations and results are relevant to a better understanding of wave propagation in deep strata,which provide some new theoretical insights in the rock physics,hydrocarbon exploration and stress detection in deep-strata shale reservoirs.

关键词： Fluid-saturated porous layered(FsPL)media In-situ stress Theory of poroacoustoelasticity Wave equation Wave dispersion and attenuation

Nanoscopic imaging of oxidized graphene monolayer using tip-enhanced Raman scattering.

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Nano Research 2018年第12期11卷 6346-6359页

作者： Joseph M.smolsky alexey V.Krasnoslobodtsev Department of Physics University of Nebraska at Omaha6001Dodge StreetOmaha NE 68182USA

Tip-enhanced Raman scattering (TERs) can be used for the structural and chemical characterization of materials with a nanoscale resolution, and offers numerous advantages compared to other forms of imaging. We use TERs to track the local structural features of a CVD-grown graphene monolayer. Ag nanoparticles were added to AFM probes using ion-beam sputtering in order to make them TERs-active. such modification provides probes with large factors of enhancement and good reproducibility. TERs measurements on graphene show an emergence of a defect-induced D-Raman band and a strain-induced shoulder of the graphene’s G-band. Comparison of TERs results with micro-Raman for oxidized graphene suggests that local oxidation occurs with the introduction of sp3 defects, under TERs conditions.

关键词： graphene Raman spectroscopy tip-enhanced Raman scattering graphene oxidation

Jellyfish search Optimization with Deep Learning Driven Autism spectrum Disorder Classification

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Computers, Materials & Continua 2023年第1期74卷 2195-2209页

作者： s.Rama sree Inderjeet Kaur alexey Tikhonov E.Laxmi Lydia Ahmed A.Thabit Zahraa H.Kareem Yousif Kerrar Yousif Ahmed Alkhayyat Department of Computer science&Engineering Aditya Engineering CollegeSurampalemAndhra PradeshIndia Department of Computer science&Engineering Ajay Kumar Garg Engineering CollegeGhaziabadUttar PradeshIndia Department of Human Resource Management Moscow Aviation InstituteMoscowRussia Department of Computer science and Engineering Vignan’s Institute of Information TechnologyVisakhapatnam530049India Computer Communication Engineering Al-Rafidain University CollegeBaghdadIraq Department of Medical Instrumentation Techniques Engineering Al-Mustaqbal University CollegeHillah51001Iraq Department of Computer Technical Engineering Al-Hadba University CollegeMosulIraq College of Technical Engineering The Islamic UniversityNajafIraq

Autism spectrum disorder(AsD)is regarded as a neurological disorder well-defined by a specific set of problems associated with social skills,recurrent conduct,and *** AsD as soon as possible is favourable due to prior identification of AsD permits prompt interferences in children with *** of AsD related to objective pathogenicmutation screening is the initial step against prior intervention and efficient treatment of children who were ***,healthcare and machine learning(ML)industries are combined for determining the existence of various *** article devises a Jellyfish search Optimization with Deep Learning Driven AsD Detection and Classification(JsODL-AsDDC)*** goal of the JsODL-AsDDC algorithm is to identify the different stages of AsD with the help of biomedical *** proposed JsODLAsDDC model initially performs min-max data normalization approach to scale the data into uniform *** addition,the JsODL-AsDDC model involves JsO based feature selection(JFsO-Fs)process to choose optimal feature ***,Gated Recurrent Unit(GRU)based classification model is utilized for the recognition and classification of ***,the Bacterial Foraging Optimization(BFO)assisted parameter tuning process gets executed to enhance the efficacy of the GRU *** experimental assessment of the JsODL-AsDDC model is investigated against distinct *** experimental outcomes highlighted the enhanced performances of the JsODL-AsDDC algorithm over recent approaches.

关键词： Autism spectral disorder biomedical data deep learning feature selection hyperparameter optimization data classification machine learning

Technological risk regulation of the subgrade base stability in permafrost areas

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Research in Cold and Arid Regions 2017年第3期9卷 321-324页

作者： s.Ya.Lutskiy T.V.shepitko alexey Y.Burukin Federal state-Funded Educational Institution of Higher Vocational Education 'Moscow state University of Railway Engineering' MGUPs (MIIT) Public Joint stock Company 'MOsTOTREsT' (PJsC 'MOsTOTREsT')

Maintenance and risk estimation of a weak roadbed condition during the construction period are ***-management procedure for unstable,weak soils is proposed through adjusting the technological loads and real-time monitoring of their *** efficiency of implementing maximum allowable vibroloads and the drainage system for strengthening weak soils is shown in the example of the Northern Latitudinal Railway area.

关键词： roadbed technology risk stability

Topology of triple-point metals

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Chinese Physics B 2019年第7期28卷 54-72页

作者： Georg W.Winkler sobhit singh alexey A.soluyanov Microsoft Quantum Microsoft Station Q University of California Santa Barbara California 93106-6105 USA Department of Physics and Astronomy Rutgers University Piscutuwny New Jersey 08854 USA Institute of Physics University of Zurich. Winterthurerstrasse 190 8057 Zurich Switzerland Department of Physics. st. Petersburg state University St. Petersburg 199034Russia

We discuss and illustrate the appearance of topological fermions and bosons in triple-point metals where a band crossing of three electronic bands occurs close to the Fermi *** bosons appear in the phonon spectrum of certain triple-point metals, depending on the mass of atoms that form the binary triple-point *** first provide a classification of possible triple-point electronic topological phases possible in crystalline compounds and discuss the consequences of these topological phases, seen in Fermi arcs, topological Lifshitz transitions, and transport *** we show how the topological phase of phonon modes can be extracted and proven for relevant ***,we show how the interplay of electronic and phononic topologies in triple-point metals puts these metallic materials into the list of the most efficient metallic thermoelectrics known to date.

关键词： topological metals topological phonons electronic structure thermoelectrics