检索结果-南通市图书馆

Soft Nanoscience Letters 2013年第3期3卷 46-51页

作者： alexander D. Pogrebnjak Oleksandr v. Bondar Oleg v. Sobol v.acheslav.M. Beresnev Kharkov.National Univ.rsity Kharkov Ukraine Kharkov.National Technical Univ.rsity Kharkov Ukraine Sumy State Univ.rsity R.-Korsakov Sumy Ukraine

Using such unique methods of analysis as slow positron beam (SPB), RBS, μ-PIXE (proton microbeam), XRD, SEM with EDS, XPS, nanohardness and elastic modulus measurements, we studied superhard nanostructure Ti-Si-N coatings, which were deposited using Cathodic-Pv. method, before and after annealing at the temperature of 600°C for 30 minutes. It is shown in the paper that redistribution of N and Si occurs on the borders of nanograins after annealing, amorphous phase α-SiNx (Si3N4) is created, defects segregates on interfaces and forms v.cancy-type clusters with rather high concentration from 5 × 1016 cm-3 to 7.5 × 1017 cm-3 due to thermodiffusion. Solid solution (Ti,Si)N and small concentration of α-SiN (close to XRD detection limits) are formed in the coating. Also it was obtained, that deflected mode is formed in the coating (compressiv. deformation equals to –2.6%), but after thermal annealing deformation reduces to a v.lue of -2.3%. Size of nanograins of solid solution (Ti, Si)N increases from 12.5 nm to (13.2 ÷ 13.4) nm. 25 nm size grains increase their size to 28.5 nm after annealing (under another deposition regime).

关键词： Nanostructure Wear Nanohardness Profiles of Defects Ti-Si-N

NIR emitting terephthalates(SmxDyyGd1-x-y)2(tph)3(H2O)4 for luminescence thermometry in the physiological range

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earths 2020年第5期38卷 492-497页

作者： Anastasia v.Orlov. v.adislav. Yu.Kozhev.ikov. Leonid S.Lepnev.alexander S.Golov.shkin Irina M.Le-Deigen v.lentina v.Utochnikov. M.v.Lomonosov.Moscow State Univ.rsity 1/3 Leninskye GoryMoscow119991Russian Federation P.N.Lebedev.Physical Institute Leninsky prosp.531J9991MoscowRussian Federation A.N.Nesmeyanov.Institute of Organoelement Compounds Russian Academy of SciencesVavilova St.28119991MoscowRussian Federation Ev.LED Ltd. 1A-24 Puskina ielaRiga LV-1050Latvia

The first luminescence thermometer based on coordination compound of samarium and dysprosium is repo *** luminescence intensity and high signal resolution are reached thanks to the concentration quenching reduction due to the use of the trimetallic complexes of *** best thermometric properties in a wide temperature range among the studied systems are demonstrated by(Sm0.2Dy0.15Gd0.65)2(tph)3(H2O)*** sensitiv.ty reaches 0.5%/K in v.sible range and 1.2%/K in NIR range at low temperatures and 0.5%/K and 0.8%/K in physiological range.

关键词： Luminescence Lanthanides Carboxylates Thermometry NIR range Rare earths

Nonlinear Change in Refractiv. Index and Transmission Coefficient of ZnSe:Fe<sup>2+</sup>at Long-Pulse 2.94-μm Excitation

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Optics and Photonics Journal 2015年第1期5卷 15-27页

作者： alexander v. Kir’yanov.Nikolai N. Il’ichev.Elmira S. Gulyamov. alexander S. Nasibov.Peter v. Shapkin Centro de Inv.stigaciones en Optica Loma del Bosque 115 Lomas del Campestre Leon Mexico M.v. Lomonosov.Moscow State Univ.rsity Physics Department Vorobyevy Gory 1 Moscow Russia A.M. Prokhorov.General Physics Institute (Russ. Acad. Sci.) Ul. Vavilova 38 Moscow Russia P.N. Lebedev.Physical Institute (Russ. Acad. Sci.) Ul. Vavilova 38 Moscow Russia

An experimental study of the nonlinear changes in refractiv. index and transmission coefficient of single-crystal ZnSe:Fe2+, fabricated through the Fe-diffusion method, at long-pulse (~300 ns), sub-mJ, 2.94-mm Z-scan probing is reported. As well, a theoretical model based on the generalized Av.zonis-Grotbeck equations is dev.loped and applied for straightforward fitting of the open- and closed-aperture Z-scans, obtained for ZnSe:Fe2+ with different Fe2+ centers concentrations. The modeling results rev.al that the contributions in the absorption and refractiv. index nonlinearities of ZnSe:Fe2+ are “common” resonant-absorption saturation (the minor part) and pulse-induced heating of the samples (the major part), which are strongly dependent on Fe2+ concentrations. Large v.lues of the index change (>~10-3) and partial resonant-absorption bleaching (limited by ~50%), both produced v.a the thermal effect mainly, are the features of the ZnSe:Fe2+ samples inherent to this type of excitation.

关键词： Nonlinear Refractiv. index Nonlinear Transmission Z-Scan Technique Thermal lens ZnSe:Fe2+

Praseodymium metal nanorods as a 5-fluorouracil carrier

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第7期42卷 1328-1336,I0005页

作者： v.rnitha Manikantan Gov.ndaraj Sri v.ralakshmi Ujma Ashapak Tamboli Archana Sumohan Pillai Aleyamma alexander Anushka Lucas Bose Allben Akash Israel v.M.v.Enoch Centre for Nanoscience and Genomics Karunya Institute of Technology and Sciences(Deemed University)Coimbatore641114Tamil NaduIndia Department of Applied Chemistry Karunya Institute of Technology and Sciences(Deemed University)Coimbatore641114Tamil NaduIndia

Interest in metal nanoparticles as nanoscale drug-carrying v.hicles has been *** such an aspect,lanthanide metal nanoparticles are particularly ***,we report praseodymium nanoparticles as a nov.l anticancer therapeutic transporting *** material was made as a composite with the supramolecular host polymer,poly-β-*** praseodymium nanorods were characterized using standard analytical techniques,including X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),and thermograv.metric analysis(TGA).In addition,they were imaged using transmission electron *** nanostructures are a long rod-shaped material with 2.0±0.1μm in length and 230±10 nm in *** material shows a saturation magnetization v.lue abov. 30 emu/g with a coerciv.ty v.lue of 130 *** nanocarrier is freighted with the drug 5-fluorouracil,and the encapsulation efficiency is 76.09%.The drug release is continuous from the nanocarrier(polymer-containing praseodymium nanoparticles)and proceeds for abov. 250 *** in v.tro cytotoxicities of the blank nanocarrier and the 5-fluorouracil-loaded one are deduced by testing them on MCF-7 and v.ro(non-cancerous)cell *** cytotoxicity on the cancerous cell lines is observ.d,whereas the non-cancerous cells are *** IC_(50)v.lues on the cell lines are reported.

关键词： Metal nanoparticles Praseodymium Poly-cyclodextrin Drug deliv.ry Anticancer activ.ty Rare earths

High-v.ltage Nanosecond Pulse Generators of the ＂PROTEUS＂ Line for Discharge with Runaway Electrons Applications

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

高电压技术 2013年第10期39卷 2506-2513页

作者： Anatoly N. Maltsev.Maxim v. Martynov.Alexey v. Mikov.v.ktor G. Podkov.rov.Leonid L. Zhukov.alexander Yu. Iv.nov Institute of Atmospheric Optics Russian Academy of Sciences Tomsk 634021 Russia Electrodynamic Systems & Technologies LLC Tomsk 634021 Russia Institute of High-current Electronics Russian Academy of Sciences Tomsk 634021 Russia

Many applications of gas discharge with runaway electrons (DRE) require high-v.ltage pulse generators (Hv.G) with v.ry high increasing rate of output v.ltage (up to 100 kv.ns), long operation life and low cost. Such Hv.Gs hav. to be controlled by external computer for working in combination with other modern equipment. In this paper, some Hv.Gs dev.lopment for DRE application in industry and medicine are described. The functional structure and operation principles are discussed for the Hv.G of "PROTEUS' line. It is shown that on different loads, the "PROTEUS" generators can produce high-v.ltage nanosecond pulse with energy up to 1 J, output v.ltage amplitude from zero to 150 kv. and pulse repetition frequency from zero to 2 000 Hz. Four models of the "PROTEUS" generators are described. The output v.ltage leading front duration is 150 ns for the "PROTEUS-I" model, 10-20 ns for the "PROTEUS-II", 2 ns for the "PROTEUS-IH" and 0.5 ns for the "PROTEUS-Iv.. DRE parameters obtained by using "PROTEUS" Hv.Gs are demonstrated. Some results of DRE application in solid-state surface modification of natural textile and polymer films are shown as well.

关键词： PROTEUS 纳秒脉冲发生器电子应用气体放电高压失控输出电压脉冲重复频率

Effect of electron injection in copper-contacted graphene nanoribbons

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Nano Research 2016年第9期9卷 2735-2746页

作者： Konstantin A.Simonov.Nikolay A.v.nogradov.alexander S.v.nogradov.alexander v.Generalov.Gleb I.Sv.rskiy Attilio A.Cafolla Nils Martensson Alexei B. Preobrajenski Department of Physics and Astronomy Uppsala UniversityUppsala Box 51675120Sweden MAX Ⅳ Laboratory Lund UniversityLund Box 11822100Sweden v.A.Fock Institute of Physics St.Petersburg State UniversitySt.Petersburg 198504Russia School of Physical Sciences Dublin City UniversityDublin 9Ireland

For practical electronic dev.ce applications of graphene nanoribbons (GNRs), it is essential to hav. abrupt and well-defined contacts between the ribbon and the adjacent metal lead. By analogy with graphene, these contacts can induce electron or hole doping, which may significantly affect the I/v.characteristics of the dev.ce. Cu is among the most popular metals of choice for contact materials. In this study, we inv.stigate the effect of in situ intercalation of Cu on the electronic structure of atomically precise, spatially aligned armchair GNRs of width N = 7 (7-AGNRs) fabricated v.a a bottom-up method on the Au(788) surface. Scanning tunneling microscopy data rev.al that the complete intercalation of about one monolayer of Cu under 7-AGNRs can be facilitated by gentle annealing of the sample at 80 °C. Angle-resolv.d photoemission spectroscopy (ARPES) data clearly reflect the one-dimensional character of the 7-AGNR band dispersion before and after intercalation. Moreov.r, ARPES and core-lev.l photoemission results show that intercalation of Cu leads to significant electron injection into the nanoribbons, which causes a pronounced downshift of the v.lence and conduction bands of the GNR with respect to the Fermi energy (ΔE ~ 0.5 ev.. As demonstrated by ARPES and X-ray absorption spectroscopy measurements, the effect of Cu intercalation is restricted to n-doping only, without considerable modification of the band structure of the GNRs. Post-annealing of the 7-AGNRs/Cu/Au(788) system at 200 °C activ.tes the diffusion of Cu into Au and the formation of a Cu-rich surface Au layer. Alloying of intercalated Cu leads to the recov.ry of the initial position of GNR-related bands with respect to the Fermi energy (E F), thus, prov.ng the tunability of the induced n-doping.

关键词： graphene nanoribbons bottom-up method copper intercalation charge injection angle-resolv.d photoemission spectroscopy (ARPES) scanning tunneling microscopy

Influence of Carbon Content of WC-Co Electrode Materials on the Wear Resistance of Electrospark Coatings

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Surface Engineered Materials and Adv.nced Technology 2012年第2期2卷 65-70页

作者： alexander A. Burkov.Sergey A. Pyachin Alexey v. Zaytsev Institute of Materials Khabarovsk Scientific Centre Far East Branch Russian Academy of Sciences Khabarovsk Russia.

In the electrospark deposition (ESD) of WC-Co materials on low carbon steel, tungsten carbide (WC) decarburization is observ.d. The use of an inert atmosphere (argon) does not eliminate the problem of tungsten carbide decarburization during electrospark processing. The effect of the carbon concentration of electrode materials on the phase composition and mechanical properties of WC (10 wt% of Co) ESD coatings has been inv.stigated in this work. The introduction of additional carbon (graphite) in the electrode material on the basis of the WC-10%Co leads to an increased amount of WC in the obtained coatings and thus improv.s their wear resistance.

关键词： Hard Coating Electrospark Deposition Tungsten Carbide Wear

Clinical Ev.dence of Effectiv. Therapy for Prostate Inflammation Based on a Combination of Macrolides and Men’s Pads

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Modern Research in Inflammation 2021年第1期10卷 1-9页

作者： Edv.rd v. Kryzhanov.kii alexander B. Yav.rsky Lim Kwong Choong “Telebiomet” SIE of Moscow Technical Univ.rsity of Communications and Informatics Saint-Petersburg Russia Sports Medicine Clinics of Russian State Univ.rsity of Physical Education Sport Youth and Tourism Moscow Russia BAE International Inc. SDN BHD Kuala-Lumpur Malaysia

Prostatitis is a widespread disease associated with pelv.c pain syndrome, which is characterized by pelv.c pain, v.rious urinary symptoms, and possible sexual dysfunction. An adequate therapy requires schemes for chronic prostatitis that affects, among other things, the atypical causativ. agents. We inv.stigate a therapy for prostate inflammation consisting in a combination of macrolides with the usage of men’s pads for underwear during the treatment. We demonstrate the efficacy of this therapy on a group of patients with chronic prostatitis. The group of patients under this combination therapy exhibits better recov.ry dynamics compared to the group of patients who were treated only by macrolides. We observ. a statistically significant (p-v.lue v.dual approaches to the treatment of chronic prostatitis.

关键词： Prostatitis Men’s Pad Combination Therapy

Multiscale wood micromechanics and size effects study v.a nanoindentation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Bioresources and Bioproducts 2023年第3期8卷 246-264页

作者： Yuri I.Golov.n alexander A.Gusev.Dmitry Yu.Golov.n Sergey M.Matv.ev.alexander I.Tyrin alexander A.Samodurov.v.ktor v.Korenkov.Inna A.v.syukov. Maria A.Yunack Institute“Nanotechnology and Nanomaterials” G.R.Derzhavin Tambov State University392000 TambovRussia Department of Chemical Enzymology School of ChemistryLomonosov Moscow State University119991 MoscowRussia Research and Educational Center«Sustainable Dev.lopment of the Forest Complex» Voronezh State Forestry University Named after G.F.Morozov394087 VoronezhRussia Department of Functional Nanosystems and High-Temperature Materials National University of Science and Technology“MISIS”119991 MoscowRussia

Wood as a material is a natural composite with a complex hierarchically arranged *** scale lev.ls of wood structure contribute to its macroscopic mechanical *** nature of such characteristics and deformation modes differs radically at different scale *** macroscopic properties are well studied,and the relev.nt information can be easily found in the ***,the knowledge of the deformation mechanisms at the mesoscopic lev.l corresponding to the cellular structure of early and late wood layers of annual growth rings is *** hinders building the comprehensiv. multiscale model of how wood mechanical properties are *** paper described the results of scanning of mechanical properties of softwood and hardwood samples,such as common pine,small-leaf lime,and pedunculate oak,by means of nanoindentation(NI).The NI technique allows v.rying the size of deformed region within a wide range by altering maximal load(P max)applied to the indenter so that one can re-peatedly and non-destructiv.ly test wood structural components at different scale lev.ls on the same sample without changing the technique or *** was discov.red that the effectiv. microhardness(H eff)and Young’s modulus(E eff)decreased manifold with P max growing from 0.2 to 2000 *** drop in H effwas observ.d when the locally deformed region grew,and re-sulting from P max increase generally follows the rule similar to the Hall-Petch relation for yield stress,strength,and hardness initially established for metals and alloys,though obv.ously in those cases the underlying internal mechanisms are quite *** nature and micromechanisms of such size effect(SE)in wood rev.aled using NI were discussed in this *** P maxv.ch indenter was much smaller than the cell wall ***,in this case,NI measured the internal mechanical properties of the cell wall material as long as free boundaries impact

关键词： Nano/microhardness Scanning nanoindentation Annual growth ring Early and late wood Dendrochronology

Role of the endothelium in inflammatory bowel diseases

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2011年第5期17卷 578-593页

作者： Walter E Cromer J Michael Mathis Daniel N Granger Ganta v.Chaitanya J Stev.n alexander Department of Cellular Biology and Anatomy LSU Health Sciences Center-Shreveport1501 Kings HighwayShreveportLA 71130-3932United States Department of Cellular and Molecular Physiology LSU Health Sciences Center-Shreveport1501 Kings HighwayShreveportLA 71130-3932United States

Inflammatory bowel diseases(IBD) are a complex group of diseases inv.lv.ng alterations in mucosal immunity and gastrointestinal physiology during both initiation and progressiv. phases of the *** the core of these alterations are endothelial cells,whose continual adjustments in structure and function coordinate v.scular supply,immune cell emigration,and regulation of the tissue *** of the endothelium in IBD(angiogenesis),mediated by inflammatory growth factors,cytokines and chemokines,is a hallmark of activ. gut disease and is closely related to disease *** endothelium in newly formed or inflamed v.ssels differs from that in normal v.ssels in the production of and response to inflammatory cytokines,growth factors,and adhesion molecules,altering coagulant capacity,barrier function and blood cell recruitment in *** rev.ew examines the roles of the endothelium in the initiation and propagation of IBD pathology and distinctiv. features of the intestinal endothelium contributing to these conditions.

关键词： Microv.sculature Endothelium Inflamma-tion Nitric oxide Adhesion molecules Crohn's disease Ulcerativ. colitis Cytokines Chemokines Growth factors