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Structural and luminescence enhancement properties of Eu^(3+)/Ag nanocrystallites doped SiO_2-TiO_2 matrices

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Journal of Rare Earths 2013年第5期31卷 441-448页

作者： Arun Kumar K v Revathy K P Prathibha vasudevan Sunil Thomas Biju P R Unnikrishnan n v School of Pure & Applied Physics Mahatma Gandhi University

We reported here the structural and optical characterisation of silver nanocrystallites/Eu3＋：SiO2-TiO2 matrices synthesised through sol-gel route. Structural characterisations were done by using energy dispersive spectroscopy （EDX）, X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FTIR）, atomic force microscope （AFM） and transmission electron microscopy （TEM） measurements and optical characterisations were performed by absorption and emission spectroscopy. The TEM and XRD measurements confirmed the presence of nanocrystals. A broad absorption band was observed due to surface plasmon resonance of silver nanocrystals. The effect of silver nanocrystals on the emission spectrum of Eu3＋ doped SiO2-TiO2 matrices was discussed. An attempt was made to explain this fluorescence enhancement by invoking phenomena such as energy transfer, asymmetry ratio, surface plasmon, surface roughness, crystallinity and grain boundary. Our analysis, based on the experimental results, suggested that all the phenomena except crystallinity and grain boundary had favourable effects on fluorescence enhancement. We also estimated the relevant parameters associated with the phenomena that affected the fluorescence emission from the Eu3＋ ions in the matrix. It was seen that the theoretical estimate of fluorescence enhancement agreed well with the experimental estimate.

关键词： sol-gel luminescence SiO2-TiO2 silver nanoparticles rare earths

Asymptotics for filtration of polydisperse suspension with small impurities

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Applied Mathematics and Mechanics(English Edition) 2021年第1期42卷 109-126页

作者： L.I.KUZMInA Y.v.OSIPOv T.n.GORBUnOvA Department of Applied Mathematics National Research University Higher School of EconomicsMoscow 101000Russia Department of Applied Mathematics Moscow State University of Civil Engineering(National Research University)Moscow 129337Russia

A model for deep bed filtration of a polydisperse suspension with small impurities in a porous medium is *** suspended particles move with the same velocity as the carrier water and get blocked in the pore throats due to the size-exclusion mechanism of particle retention.A solution of the model in the form of a traveling wave is *** global exact solution for a multiparticle filtration with one high concentration and several low concentrations of suspended particles is obtained in an explicit *** analytic solutions for a bidisperse suspension with large and small particles are *** profiles of the retained small particles change monotony with *** global asymptotics for the filtration of a polydisperse suspension with small kinetic rates is constructed in the whole filtration zone.

关键词： deep bed filtration suspension colloid porous medium particle size distribution analytical model

nUMERICAL CHARACTERIZATIOn OF CURREnT-InDUCED CHAnGES In SURFACE MORPHOLOGY OF THIn Ag FILMS

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Acta Metallurgica Sinica(English Letters) 2003年第4期16卷 249-255页

作者： A.v.Parian H.G.Chun A.R.Shuourov S.v.Panin n.v.Pykhtin InstituteofStrengthPhysicsandMaterialsScienceSBRAS TomskRussia ReMM SchoolofMaterialsScienceandEngineeringUniversityofUlsanUlsanKorea TomskPolytechnicalUniversity TomskRussiaManuscriptreceived25November2002

The changes in surface topography of thin conducting Ag films under high-density current condition are studied by optical and scanning tunnelling microscopy (STM). It is established that the loss of conductivity in specimens occurs through depletion of the material due to their overheating and electromigration process. It has been shown that the r.m.s. roughness, the fractal dimension of voids and the fractal dimension of the surface allow complete numerical characterization of surface topography changes in thin Ag films.

关键词： STM thin Ag films surface roughness fractal dimension

Influence of Zr and Mn additions on microstructure and properties of Mg-2.5wt%Cu-Xwt%Zn(X=2.5,5 and 6.5)alloys

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International Journal of Minerals,Metallurgy and Materials 2022年第9期29卷 1733-1745页

作者： A.v.Koltygin v.E.Bazhenov I.v.Plisetskaya v.A.Bautin A.I.Bazlov n.Y.Tabachkova O.O.voropaeva A.A.Komissarov v.D.Belov Foundry Department National University of Science and Technology(MISiS)Moscow 119049Russia Department of Metallurgy Steel New Production Technologies and Protection of MetalsNational University of Science and Technology(MISiS)Moscow 119049Russia Laboratory of Advanced Green Materials National University of Science and Technology(MISiS)Moscow 119049Russia Department of Materials Science of Semiconductors and Dielectrics National University of Science and Technology(MISiS)Moscow 119049Russia Fianit Laboratory(Laser Materials and Technology Research Center at GPI) Prokhorov General Physics Institute RASMoscow 119991Russia Laboratory of Hybrid nanostructured Materials National University of Science and Technology(MISiS)Moscow 119049Russia Laboratory of Medical Bioresorption and Bioresistance Moscow State University of Medicine and DentistryMoscow 127473Russia

This work studied the effects of adding Zr and Mn in amounts less than 1wt%on the microstructure,mechanical properties,casting properties,and corrosion resistance of Mg-Zn-Cu alloys containing 2.5wt%Cu and 2.5wt%-6.5wt%*** hardness and electrical conductivity measurements were used to find an optimal heat treatment schedule with the best mechanical *** has been established that Zr significantly increases the yield strength of the alloys due to a strong grain refinement ***,the presence of Mn and Zr has a detrimental effect on alloy’s elongation at *** was shown that the precipitation of the Mg_(2)Cu cathodic phase in the alloy structure negatively affects the corrosion ***,the addition of Mn decreases the corrosion rate of the investigated *** best combination of the mechanical,casting,and corrosion properties were achieved in the alloys containing 2.5wt%Cu and 5wt%***,the Mn or Zr addition can improve the properties of the alloys;for example,the addition of Mn or Zr increases the fluidity of the alloys.

关键词： magnesium alloy Mg-Zn-Cu casting alloy Mn addition Zr addition

Chemical behaviour of Al/Cu nanoparticles in water

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Progress in natural Science:Materials International 2015年第1期25卷 1-5页

作者： n.v.Svarovskaya A.v.Berenda O.v.Bakina E.A.Glazkova A.S.Lozhkomoev E.G.Khorobraya v.v.Domashenko M.I.Lerner A.n.Fomenko Institute of Strength Physics and Materials Science Siberian Branch of the Russian Academy of Sciences (ISPMS SB RAS)2/4 pr.Akademichesky ave. Tomsk 634021 Russia national Research Tomsk State University (TSU) 36 Lenina ave. 634050 Tomsk Russia national Research Tomsk Polytechnic University (TPU) 30 Lenina ave. 634050 Tomsk Russia

Bimetallic Al/Cu nanoparticles with Al/Cu composition 10:90, 20:80, 40:60 were produced by method of simultaneous electrical explosion of metal pairs in the argon atmosphere. nanopowders containing 20% and 40% (mass) of aluminum interacted with water at 40–70 ℃ and formed composite particles that were porous structures of nanopetal pseudoboehmite with nanosized copper-containing inclusions inside. Aluminum in nanopowder with Al/Cu composition 10:90 did not react with water, as far as it is in the phase of intermetallic compounds Сu Al2and С*** produced can be used as an active component of antibacterial agents.

关键词： nanopowders Bimetallic nanoparticles Composite nanoparticles

Effect of acoustic pulses and EHF radiation on multipotent marrow stromal cells in tissue engineering constructs

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Journal of Innovative Optical Health Sciences 2017年第1期10卷 75-83页

作者： R.K.Chailakhyan v.I.Yusupov Yu.F.Gorskaya A.I.Kuralesova Yu.v.Gerasimov A.P.Sviridov A.Kh.Tambiev n.n.vorobieva A.G.Grosheva v.v.Shishkova I.L.Moskvina v.n.Bagratashvili n.F.Gamaleya Research Institute of Epidemiology and Microbiology Ministry of Health of the Russian Federation 18 GamaleyiMoscow 123098Russia v.I.I'ichev Pacific Oceanological Institute Far-Eastern Division of Russian Academy of Sciences43 BaltiskayaVladivostok 690041Russia Institute on Laser and Information Technologies of Russian Academy of Sciences 2 PionerskayaTroitskMoscow 142190Russia Biological Faculty of Moscow State University 1-12 Leninskiye Gory MSUMoscow 119234Russia

In this paper,we studied the effects of physical factors,such as,acoustic pulses of laser-induced hydrodynamics(ALIH)and extremely-high frequencies(EHF)radiation,on the formation of heterotopic bone marrow organs.A suspension of precipitated bone marrow cells from CBA mice were exposed to ALIH pulses and EHF radiation separately and in their com bination tissue engineering constructs,presenting gelatin sponges 2 by 2 by 2 mm in size containing 10^(7)nucleated bone marrow cells,were exposed to physical factors and were implanted under the renal capsules of syngeneic *** newly formed hematopoietic organs were examined in three and five months later after *** five months old transplants were bigger in size than the three months old *** number of hematopoietic cells in the rest of the groups increased during this period by a factor from 3 to 10,the increase being as high as 20-fold in the:ALH+EHF *** concentration of multipotent stromal cells(MSCs)was in the EHF+ALIH,and minimal concentration was in the ALIH+*** accumulation rate of bone capsule weight was highest for the transplants of EHF+ALIH and ALIH-sponge groups during the first three *** data showed that the combined impact of the EHF+ALIH on MSCs is the most effective for the formation of bone marrow transplantation.

关键词： Multipotent stromal cells heterotopic transplantation extremely high frequency radiation laser-induced hydrodynamics acoustic pulses.

COMPARATIvE TREATMEnT OF ACnE vULGARIS USInG PALOMAR LUX APPLIQU´E TECHnIQUE AnD DIRECT InTRALESIOnAL InJECTIOn

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Journal of Innovative Optical Health Sciences 2009年第3期2卷 279-287页

作者： ELInA A.GEnInA ALEXEY n.BASHKATOv vALERY v.TUCHIn GEORGY v.SIMOnEnKO vERA n.SHERSTnEvA ILYA v.YAROSLAvSKY GREGORY B.ALTSHULER Department of Optics and Biophotonics Saratov State University 83 Astrakhanskaya str. Saratov 410012Russia Saratov State Medical University 112 B.Kazachya str. Saratov 410012Russia Palomar Medical Technologies Inc. 82 Cambridge St.Burlington 01803MAUSA

Intralesional injection of triamcinolone(TMC)preparations is an effective therapy for cystic acne ***,invasive delivery techniques limit the use of this modality to a relatively narrow class of *** permeability can be enhanced through creating a lattice of microzones(islets)of light-induced limited thermal damage in the upper layers of *** this paper,we directly compared safety and efficacy of delivering TMC acetonide with this novel technique versus conventional intralesional injection for treatment of inflammatory acne lesions.A combination of an intense pulsed light system and a specially designed appliqu´e with a pattern of absorbing centers has been used to create the lattice of islets of damage(LID).Quantitative analysis has included estimation of the following parameters:redness,diameter,and height of acne *** photography has been used to document dynamics of lesion development at successive visits(two hours,24 hours and one week post-treatment).Seven subjects have participated in the *** difference in lesion dynamics between the treatment and control groups was observed at two-hours *** 24-hours/one-week follow-ups,TMC-injected and TMC-LID-delivered groups have demonstrated 82%/93%and 80%/89%improvement in height of lesions in comparison to control(60%/68%).Delivery of TMC with the newly proposed LID technique is at least as effective as intralesional injection for treating inflammatory acne *** of skin permeability using LID approach is a promising technique for accelerating delivery of various compounds to their target areas in the skin.

关键词： Acne vulgaris drug delivery skin permeability enhancement.

Etiology of invasive candidosis agents in Russia： a multicenter epidemiological survey

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Frontiers of Medicine 2018年第1期12卷 84-91页

作者： n.v. vasilyeva E.R. Raush M.v. Rudneva T.S. Bogomolova A.E. Taraskina Yong Fang Fengmin Zhang n.n. Klimko Department of Medical Microbiology North-Western State Medical University named after L I. Mechnikov St. Petersburg 194291 Russia Kashkin Research Institute of Medical Mycology North-Western State Medical University named after 1.1. Mechnikov St. Petersburg 194291 Russia Sino-Russia Institute of Infection and Immunity Department of Microbiology Harbin Medical University Harbin 150086 China Department of Clinical Mycology Allergy and Immunology North-Western State Medical University named after I.I. Mechnikov St. Petersburg 194291 Russia

A multicenter prospective epidemiological survey on the etiologic agents of invasive candidosis was conducted in Russia in the period of 2012-2014. Samples were collected from 284 patients with invasive candidosis and Candida species isolated by culture. The species were identified by DnA sequencing and MALDI-TOF mass- spectrometry. A total of 322 isolates were recovered, in which 96% of Candida species belonged to six major species, namely, C. albicans （43.2%）, C. parapsilosis （20.2%）, C. glabrata （11.5%）, C. tropicalis （9.6%）, C. krusei （6.2%）, and C. guilliermondii （5.3%）. Most Candida species were isolated from blood samples （83.23%）. notably, the prevalence rate of C. albicans reduced from 52.38% to 32.79% （2012 vs. 2014）（P = 0.01） whereas that of non-C. albicans increased from 47.62% （2012） to 67.21% （2014）（P〈 0.01）. Species distribution differed among geographical regions; specifically, the prevalence rate of C. albicans as an etiologic agent of invasive candidosis in Siberian Federal region was significantly higher than that in other Federal regions. Results indicated a shift from C. albicans to non-C, albicans. Therefore, a detailed investigation on the contributing factors and appropriate treatment of invasive candidosis is needed.

关键词： prevalence Candida species invasive candidosis nosocomial etiology MALDI-TOF mass-spectrometry candidemia

The theory of direct magnetoelectric effect in the bilayer system of ferromagnetic–piezoelectric

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Journal of Advanced Dielectrics 2016年第1期6卷 55-60页

作者： v.n.nechaev A.v.Shuba Department of Mathematics and Physical-Mathematical Modelling voronezh State Technical University Moskowsky Prospect Street Voronezh 394026Russian Federation

The theory of direct magnetoelectric(ME)effect in a bilayer of ferromagnetic and piezoelectric is developed taking into account nonuniform distribution of electrical field on a piezoelectric layer *** simultaneous solution of the motion equations for piezoelectric and ferromagnetic mediums allowed to numerically and analytically calculate the dependence of natural mechanical oscillation on structure parameters and to determine the dependence of ME effect coefficient on frequency of the variable magnetic field.

关键词： Bilayer system magnetoelectric effect natural frequency of oscillations longitudinal magnetoelectric voltage coefficient nonuniform electric field