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Particuology 2023年第6期77卷 47-55页

作者： R.f.Mardanov S.K.Zaripov V.f.Sharafutdinov N.I.Lobachevskii Institute of Mathematics and Mechanics Kazan(Volga Region)Federal UniversityKremlevskaya ul.18KazanTatarstan420008Russia

The efficiencies of the diffusion deposition of nanoaerosols for a single fiber for the models of aerosol filter and wire mesh screen are studied numerically in the extended range of the Peclet number *** rectangular periodic cell model for fluid flow and convective-diffusive transport of small aerosol particles is *** of the previous theoretical and experimental studies of single fiber diffusion deposition efficiency were for the case of Pe>*** array with uniform square or chess grid of fibers and of a row of circular cylindrical fibers are considered as the filter and wire mesh screen *** flow and particles transport equations are solved numerically using the Boundary Element *** obtained numerical data are used to derive the approximate formulas for the deposition efficiency in the entire range of the Peclet number for the various porosities of the filter medium or distances between fibers in a wire mesh *** derived dependencies take into account nonlinearity of the deposition efficiency at the low Peclet *** obtained analytical dependencies compare well with the numerical and experimental data.

关键词： Arrayof fibers Row of fibers Periodic cell model Convection-diffusion equation Single fiber efficiency

Charge susceptibilities of armchair graphene nanoribbon in the presence of magnetic field

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Chinese Physics B 2016年第9期25卷 511-517页

作者： H Rezania f Azizi Department of Physics Razi University

We present the behaviors of both dynamical and static charge susceptibilities of undoped armchair graphene nanoribbon using the Green＇s function approach in the context of tight binding model ***,the effects of magnetic field on the the plasmon modes of armchair graphene nanoribbon are investigated via calculating the correlation function of charge density *** results show that the increase of magnetic field makes the high-frequency plasmon mode for both metallic and insulating cases *** also show that low-frequency plasmon mode for metallic nanoribbon appears due to increase of magnetic ***,the number of collective excitation modes increases with ribbon width at zero magnetic ***,the temperature dependence of the static charge structure factor of armchair graphene nanoribbon is *** effects of both magnetic field and ribbon width on the static charge structure factor are discussed in detail.

关键词： armchair graphene nanoribbon Green's function

Spatial distribution of insecticide resistant Check update populations of Aedes aegypti and Ae. albopictus and first detection of V410L mutation in Ae. aegypti from Cameroon

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Infectious Diseases of Poverty 2022年第4期11卷 96-97页

作者： matthew Montgomery James f.Harwood Aurelie P.Yougang Theodel A.Wilson-Bahun Armel N.Tedjou Christophe Rostand Keumeni Auston Marm Kilpatrick Charles S.Wondj Basile Kamgang Centre for Research in Infectious Diseases P.O.Box 13591YaoundeCameroon 不详

Background:Dengue(DENV),chikungunya(CHIKV)and Zika virus(ZIKV),are mosquito-borne viruses of medical importance in most tropical and subtropical *** control,primarily through insecticides,remains the primary method to prevent their ***,we evaluated insecticide resistance profles and identifed important underlying resistance mechanisms in populations of Aedes aegypti and *** from six different regions in Cameroon to pesticides commonly used during military and civilian public health vector control ***:Aedes mosquitoes were sampled as larvae or pupae between August 2020 and July 2021 in six locations across Cameroon and reared until the next generation,*** and *** adults from G1 were tested following World Health Organization(WHO)recommendations and *** GO adults screened with real time melting curve qPCR analyses to genotype the f1534C,V1016l and V410L Aedes kdr *** butoxide(PBO)assays and real time qPCR were carried out from some cytochrome p450 genes known to be involved in metabolic *** analyses were performed using Chi-square test and generalized linear ***:Loss of susceptibility was observed to all insecticides *** rates from tests with 0.25%permethrin varied from 24.27%to 85.89%in *** and from 17.35%to 68.08%in *** rates for 0.03%deltamethrin were between 23.30%and 88.20%in *** and between 69.47%and 84.11%in *** found a moderate level of resistance against bendiocarb,with mortality rates ranging from 69.31%to 90.26%in *** and from 86.75%to 98.95%in *** PBO pre-exposure,we found partial or fully restored suscepti bility to pyrethroids and *** genes Cyp9M6f88/87 and Cyp9J10 were overexpressed in *** populations from Douala sites resistant to permethrin and ***6P12 was highly expressed in alphacypermethrin and permethrin resistant A

关键词： Arbovirus Aedes aegypti Aedes albopictus Insecticide resistance Knock down resistance Cytochrome P450 monooxygenases Cameroon

A Label-free Detection of Biomolecules Using Micromechanical Biosensors

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Chinese Physics Letters 2013年第6期30卷 228-231页

作者： Meisam Omidi M.A.Malakoutian Mohammadmehdi Choolaei f.Oroojalian f.Haghiralsadat f.Yazdian faculty of New Science and Technology University of TehranTehranIran Department of Electrical and Computer Engineering University of TehranTehranIran Department of Chemical Engineering South Tehran BranchIslamic Azad UniversityTehranIran

A Microcantilevers resonator is used to detect a protein biomarker called prostate specific antigen(PSA),which is associated with prostate *** concentrations of PSA in a buffer solution are detected as a function of deflection of the *** this purpose,we use a surface micromachined,antibody-coated polycrystalline silicon micromechanical cantilever *** have mass sensitivities of the order of 10–17 g/Hz,which result from their small *** matter allows them to detect an immobilized antibody monolayer corresponding to a mass of about 70 *** these devices,concentrations as low as 150 fg/mL,or 4.5 fM,could be detected from the realistic samples.

关键词： cantilever resonator polycrystalline

Anosov and expanding attractors

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Science China Mathematics 2020年第9期63卷 1929-1934页

作者： Robert f.Williams Department of Mathematics University of Texas at AustinAustinTX 78705USA Institute for Advanced Study PrincetonNJ 08540USA

An earlier conjecture is settled with an immersion of a 2-dimensional branched *** obstructions in linear algebra and tiling theory are studied rst.

关键词： Anosov expanding attractor Cantor set ber bundle

A review of landscape ecology experiments to understand ecological processes

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Ecological Processes 2022年第1期11卷 802-811页

作者： Yolanda f.Wiersma Department of Biology Memorial UniversitySt.John’sNL A1C 5S7Canada

Background:One way in which we make inferences about ecological processes is via *** ecological processes happen at landscape extents and it is at this extent that experimentation is more *** review explores the intersection between experimentation,ecological processes and landscape ***,this review seeks to discover how scientists design experiments to understand ecological processes at landscape ***:I found 87 papers where these three concepts intersected,and reviewed them in more depth to assess characteristics of scale(treatment and study area extent),replication,research question and experiment ***:The findings suggest that experimental approaches for understanding ecological processes are well established,and beginning to more readily accommodate spatial ***,there is room to integrate more spatially explicit,landscape-scale experiments into studies of ecological processes.

关键词： Inference Landscape ecology Manipulative experiment Observational experiment Scale

Photometric Investigation of Contact Binary DY Cet Based on TESS Data

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Research in Astronomy and Astrophysics 2022年第5期22卷 121-128页

作者： M.f.Yildirim Canakkale Onsekiz Mart University Astrophysics Research Center and Ulupinar Observatory17020CanakkaleTurkey Canakkale Onsekiz Mart University Department of Electricity and EnergyCan Vocational School17400CanakkaleTurkey

We present a photometric analysis of the Transiting Exoplanet Survey Satellite(TESS)light curve of contact binary system DY Cet and the behavior of its orbital period *** light curve and published radial velocity data analysis was performed using the Wilson-Devinney *** a result of simultaneous analysis of the light curve with radial velocity data,the masses and radii of the system’s components were determined as M_(1)=1.55±0.02 M_(⊙),M_(2)=0.55±0.01 M_(⊙) and R_(1)=1.51±0.02 R_(⊙),R_(2)=0.95±0.02 R_(⊙),*** degree of contact(f)and mass ratio(q)of the system were determined as 23%and 0.355±0.012,*** period analysis of DY Cet was conducted for the first time in this *** was observed that the orbital period has a sinusoidal change with decreasing *** explain the orbital period change,mass transfer between components is proposed with the assumption of conservative mass,and the transfer rate was calculated to be dM/dt=1.1×10^(-7) M_(⊙)yr^(-1).A possible third component is suggested for explaining the sinusoidal change,and the mass of the unseen component was determined as 0.13 M_(⊙).The age of the DY Cet system was estimated as 3.77 Gyr.

关键词： stars eclipsing binary stars-stars fundamental parameters of stars- stars individual (DY Cet)

MHD Equilibrium with Reversed Current Density and Magnetic Islands Revisited:the Vacuum Vector Potential Calculus

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Plasma Science and Technology 2013年第10期15卷 985-988页

作者： f.L.BRAGA Gleb-Wataghin Physics Institute Applied Physics DepartmentState University of Campinas federal Institute of Science and Technology of Espirito Santo

The solution of Grad-Shafranov equation determines the stationary behavior of fusion plasma inside a tokamak. To solve the equation it is necessary to know the toroidal current density profile. Recent works show that it is possible to determine a magnetohydrodynamic （MHD） equilibrium with reversed current density （RCD） profiles that presents magnetic islands. In this work we show analytical MHD equilibrium with a RCD profile and analyze the structure of the vacuum vector potential associated with these equilibria using the virtual casing principle.

关键词： magnetohydrodynamics vacuum vector potential reversed current density magnetic islands

Nanoscale displacement of the image of an atomic source of radiation

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Chinese Optics Letters 2009年第2期7卷 149-151页

作者： Henk f. Arnoldus Department of Physics and Astronomy Mississippi State University

Light emitted by an atomic source of radiation appears to travel along a straight line （ray） from the location of the source to the observer in the far field. However, when the energy flow pattern of the radiation is resolved with an accuracy better than an optical wavelength, it turns out that the field lines are usually curved. We consider electric dipole radiation, a prime example of which is the radiation emitted by an atom during an electronic transition, and we show that the field lines of energy flow are in general curves. Near the location of the dipole, the field lines exhibit a vortex structure, and in the far field they approach a straight line. The spatial extension of the vortex in the optical near field is of nanoscale dimension. Due to the rotation of the field lines near the source, the asymptotic limit of a field line is not exactly in the radially outward direction and as a consequence, the image in the far field is slightly shifted. This sub-wavelength displacement of the image of the source should be amenable to experimental observation with contemporary nanoscale-precision techniques.

关键词： Atoms Electric dipole moments flow patterns Nanotechnology Vortex flow

On the Indeterminacy in Hardness of Shape Memory Alloys

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Journal of Materials Science & Technology 2004年第6期20卷 700-702页

作者： f.T.Cheng DeDartment of Applied Phvsics

The present communication addresses an interesting problem related to the indeterminacy in hardness of superelastic NiTi reported by Xu et al. The origin of the indeterminacy is attributed to the inadequacy of the conventional Vickers hardness testing measurement which does not record elastic deformation, and thus the indeterminacy may be removed with suitable techniques. Concepts of hardness in relation to deformation are clarified. Recommendations for measuring the hardness of NiTi and other elastic-plastic materials are suggested, together with comments on the advantages and disadvantages of each of these methods.

关键词： Hardness Elastic-plastic materials Elastic recovery Vickers microhardness test NiTi SMA