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Empirical pairing gaps and neutron-proton correlations

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Chinese Physics C 2019年第1期43卷 109-121页

作者： B.S.Ishkhanov S.v.Sidorov T.yu.Tretyakova E.v.vladimirova Faculty of Physics Lomonosov Moscow State University Skobeltzyn Institute of Nuclear Physics Lomonosov Moscow State University

Analysis of various mass formulas related to neutron-proton correlations in atomic nuclei is carried *** the example of the N =Z chain it is shown that for self-adjoint nuclei various formulas proposed in literature for estimating the np pairing energy lead to similar results. Significant differences between the calculation methods arise when nuclei with N = Z are considered, which allows to reveal the complexity of neutron-proton correlations in different types of atomic nuclei and to make assumptions on the correspondence of the mass relation to the real effect of np pairing. The Shell Model parametrization of the binding energy makes it possible to draw additional conclusions on the structure of mass formulas and their relationship.

关键词： nucleon interaction models of atomic nuclei nucleon pairing in atomic nuclei

Mesoscopic Models of Plants Composed of Metallic Nanowires

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Journal of Bionic Engineering 2013年第3期10卷 368-376页

作者： Galina K. Strukova Gennady v. Strukov Evgeniya yu. Postnova Alexander yu. Rusanov Ivan S. veshchunov Institute of Solid State Physics Russian Academy of Sciences 142432 Chernogolovka Russia

various metallic structures of complex shape resembling living plant organisms （biomimetics） are produced as a result of self-assembly of nanowires growing on porous membranes in the course of pulse current electrodeposition. These structures occur if the electroplating is continued after the nanowires appear on the membrane surface. By varying the membrane ge- ometry, pulse current electroplating parameters, and alternating electrodeposition from two baths composed of a variety of electrolytes, diverse models were fabricated, including a hollow container with a wall thickness of 10 nm 20 nm. This biomimetic method suggests an analogy between the shape-forming processes of plants and their metallic models. Nanostruc- tured mesostructures of various metals （Ag, Pd, Ni）, alloys （PdNi, Pbln） and hybrid structures .（PdNi/Pb, PdNi/Pbln） were obtained. They can be of interest for fundamental research （self-assembly, morphogenesis） as well as for applications in nanotechnology （catalysis, nanoplasmonics, medicine, superhydrophobic surfaces）.

关键词： templated growth pulse electroplating self-assembly metallic mesostructures nanowires fractal branching biomimetic method

Preparation of Long-range Ordered Nanostructures in Semicrystalline Diblock Copolymer Thin Films Using Micromolding

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Chinese Journal of Polymer Science 2014年第9期32卷 1188-1198页

作者： Peng Zhang Hai-ying Huang yu Chen Shun yu Christina Krywka Sarathlal K.vayalil Stephan v.Roth 何天白 State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Deutsches Elektronen-Synchrotron Hamburg D-22607 Germany Institute of High Energy Physics Chinese Academy of Sciences Institute for Applied and Experimental Physics University of Kiel Kiel D-24118 Germany Institute of Materials Research Helmholtz Zentrum Geesthacht D-21502 Geesthacht Germany

Long-range ordered nanostructures are prepared in the poly（styrene）-block-poly（e-caprolactone） diblock copolymer thin films using micromolding. We evaluated the change in crystallinity based on grazing-incidence X-ray diffraction and proved that the crystallinity increased with the decrease of the mold size. This means that ordered nanostructures with atomic length scale order can be adjusted by tuning the mesoscale confinement. The inherent mechanism was the cooperation of geometric confinement, microphase structure and surface-induced ordering of PS-b-PCL in the melt, which paved the way for the subsequent crystal growth. These findings establish a route to promote the cost-effective nanofabrication by combining the mature microfabrication technique with the emerging directed self-assembly of block copolymers.

关键词： Long-range ordered nanostructure Directed self-assembly Surface-induced ordering X-ray.

Influence of ZrO_(2)/SiO_(2) nanomaterial incorporation on the properties of PEO layers on Mg-Mn-Ce alloy

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Journal of Magnesium and Alloys 2022年第2期10卷 552-566页

作者： D.v.Mashtalyar I.M.Imshinetskiy K.v.Nadaraia A.S.Gnedenkov S.L.Sinebryukhov A.yu.Ustinov A.v.Samokhin S.v.Gnedenkov Institute of Chemistry Far Eastern BranchRussian Academy of SciencesVladivostok 690022Russian Federation Far Eastern Federal University Vladivostok 690922Russian Federation A.A.Baikov Institute of Metallurgy and Materials Science Russian Academy of SciencesMoscow 119991Russian Federation

The properties of coatings formed on the MA8 magnesium alloy by the plasma electrolytic oxidation in electrolytes containing mechanical mixture of zirconia and silica nanoparticles in concentrations of 2,4 and 6 g/l have been *** has been established by SEM,EDS,and XPS that ZrO_(2)/SiO_(2)nanoparticles successfully were incorporated into the ***-Raman spectroscopy showed the presence of ZrO_(2)in tetragonal and monoclinic forms in the PEO-coating composition as well as Mg_(2)SiO_(4) in tetrahedral configuration uniformly distributed in the outer part of *** coatings significantly reduce corrosion current density in comparison with bare Mg alloy and base PEOlayer(from 2.4×10^(–7)A/cm^(2) for base PEO layer to 0.7×10^(–7)A/cm^(2) for coatings with nanoparticles).It has been found that the presence of solid nanoparticles in the composition of coating has a positive effect on their hardness(this parameter was increased from 2.1±0.3 GPa to 3.1±0.4 GPa)and wearproof(the wear was reduced from(4.3±0.4)×10^(–5)mm^(3)/(N×m)to(3.5±0.2)×10^(–5)mm^(3)/(N×m)).

关键词： Plasma electrolytic oxidation Composite coatings Nanoparticles Zirconia Silica Protective coatings

Geochemistry and petrology of superpure quartzites from East Sayan Mountains, Russia

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Acta Geochimica 2019年第1期38卷 22-39页

作者： A.M.Fedorov v.A.Makrygina A.I.Nepomnyaschikh A.P.Zhaboedov A.v.Parshin v.F.Posokhov yu.v.Sokolnikova A.P.vinogradov Institute of Geochemistry SB RAS Irkutsk National Research Technical University Irkutsk Scientific Center SB RAS Irkutsk State University Geological Institute SB RAS

Quartzites are widespread within Earth's lithosphere, but their highly pure varieties occur quite infrequently. With the development of alternative energy sources, including solar, and with increasing demand for high-purity quartz for optics, interest has risen in highpurity silicon-bearing materials. The quartzites discovered in the southeast part of the Eastern Sayan Mountains are particularly attractive for exploration in terms of their raw material quality and feasibility to be enriched. For this reason, their genesis also merits study. Available geochemical data show that chemogenic(d^(18)O>29.2%)siliceous-carbonate sediments of the Irkut Formation are fairly pure(impurity elements ved carbonate components of the rock. Bedded quartzites remote from the intrusive granitoids and near-contact quartzites were recognized based on geochemical and petrographic data. Influenced by the Sumsunur granitoids, the near-contact quartzites originally contained >0.9% impurities, but later, under the action of sliding slabs of ophiolite dynamothermal treatment reduced impurities to < 100 ppm, resulting in ‘‘superquartzites' '(highly pure quartzites). The presence of only minor structural impurities is due to the enrichment capacity of superquartzites to 10.1 ppm(7.2 ppm under special conditions) of 10 elements: Fe, Al, Ti, Ca, Mg, Cu,Mn, Na, K, and Li.

关键词： High-purity quartz Superquartzite Gravitational sliding Dynamic metamorphism Recrystallization

Controlled Wettability of Polymers via Environmental Crazing

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Chinese Journal of Polymer Science 2022年第10期40卷 1307-1314,I0012页

作者： Alena yu.Yarysheva Larisa M.Yarysheva Fedor v.Drozdov Olga v.Arzhakova Aziz M.Muzafarov Faculty of Chemistry Lomonosov Moscow State UniversityLeninskieGory 1-3Moscow 119991Russia Institute of Synthetic Polymer Materials RAS ul.Profsoyuznaya 70Moscow 117393Rusia

This work highlights the benefits of environmental crazing for the control over the hydrophilic-lipophilic balance of glassy amorphous and semicrystalline polymers:poly(ethylene terephthalate)(PET)and biodegradable polycaprolactone(PCL).Task-oriented encapsulation of diverse commercial and natural hydrophilic(polyethyleneoxide,polyvinylpyrrolidone,gelatin)and hydrophobic guest additives(perfluoroorgano siloxanes,water-repellent impregnation)into mesoporous host polymer(PET,PCL)matrixes allows targeted control over the wettability of the resultant nanocomposite *** on the nature of the guest additive,the properties of the modified polymers can be varied from hydrophilic to hydrophobic:contact angle(CA)of PET can be adjusted from 47_(⊥)/38_(||)to 130_(⊥)/117_(||)°(for initial PET,CA=82°)and CA of PCL from 40°to 114°(for initial PCL CA=75°).The unique benefits of environmental crazing for structural modification are related to the universal character of this approach which can be applied to a broad range of polymers and allows preparation of diverse high-performance materials with tunable hydrophilic-lipophilic balance.

关键词： Wettability Hydrophilic-hydrophobic balance Contact angle Environmental crazing Poly(ethylene terephthalate) Polycaprolactone

Carboxylates as green corrosion inhibitors of magnesium alloy for biomedical application

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Journal of Magnesium and Alloys 2024年第7期12卷 2909-2936页

作者： A.S.Gnedenkov S.L.Sinebryukhov A.D.Nomerovskii v.S.Marchenko A.yu.Ustinov S.v.Gnedenkov Institute of Chemistry of FEB RAS 159 Pr.100-letiya VladivostokaVladivostok 690022Russia

The efficiency of the green inhibitors(sodium salts of fumarate,glycolate and gluconate)in suppressing corrosion of the structural MA8 magnesium alloy(Mg–Mn–Ce)and the biomedical Mg–0.8Ca alloy was studied using the hydrogen evolution measurements,mass loss test,EIS,PDP,SvET/*** analysis of the morphology,chemical composition,and growth kinetic of corrosion films formed in 0.9 wt%NaCl solution with and without corrosion inhibitors was carried *** most compact surface film with the smallest thickness was formed in a saline solution with sodium *** Mg alloy samples exhibited the highest polarization resistance,the lowest localized electrochemical activity,and the lowest corrosion rate in saline with the addition of sodium fumarate and sodium *** efficiency of the applied inhibitors was up to 81%.The model of the corrosion mechanism based on the sorption of molecules of organic inhibitors is *** results show the high compatibility of the used inhibitors with the calcium-phosphate PEO-matrix,indicating the possibility of forming a self-healing coating by means of these active substances.

关键词： Magnesium and its alloys Organic inhibitor Electrochemical behavior PEO-coatin Bioresorbable implant Degradation mechanism

Growth of 4＂ diameter polycrystailine diamond wafers with high thermal conductivity by 915 MHz microwave plasma chemical vapor deposition

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Plasma Science and Technology 2017年第3期19卷 93-97页

作者： A F POPOvICH v G RALCHENKO v K BALLA A K MALLIK A A KHOMICH A P BOLSHAKOv D N SOvYK E E ASHKINAZI v yu yuROv Institute of Radio Engineering and Electronics of Russian Academy of Sciences Fryazino 141190 Russia General Physics Institute of Russian Academy of Sciences Moscow 119991 Russia Harbin Institute of Technology Harbin 150001 People's Republic of China National Research Nuclear University MEPhI Moscow 115409 Russia Central Glass and Ceramic Research Institute Kolkata 700 032 India

Polycrystalline diamond（PCD） films 100 mm in diameter are grown by 915 MHz microwave plasma chemical vapor deposition（MPCvD） at different process parameters,and their thermal conductivity（TC） is evaluated by a laser flash technique（LFT） in the temperature range of230-380 *** phase purity and quality of the films are assessed by micro-Raman spectroscopy based on the diamond Raman peak width and the amorphous carbon（a-C） presence in the *** and increasing dependencies for TC with temperature are found for high and low quality samples,***,as high as 1950 ± 230 W m-1 K-1 at room temperature,is measured for the most perfect material.A linear correlation between the TC at room temperature and the fraction of the diamond component in the Raman spectrum for the films is established.

关键词： thermal conductivity polycrystalline diamond microwave plasma chemical vapordeposition Raman spectroscopy

Development of Mg-Zn-Y-Zr casting magnesium alloy with high thermal conductivity

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Journal of Magnesium and Alloys 2021年第5期9卷 1583-1593页

作者： v.E.Bazhenov A.v.Koltygin M.C.Sung S.H.Park yu.v.Tselovalnik A.A.Stepashkin A.A.Rizhsky M.v.Belov v.D.Belov K.v.Malyutin National University of Science and Technology“MISiS” Leninskiy pr.4Moscow 119049 Russia LG Electronics Inc. Yeoui-daeroYeongdeungpo-gu.128LG Twin TowerSeoul 07336 Republic of Korea

Magnesium alloys are used in aircraft because of their light ***,for these alloys to be applied in electronic devices,high thermal conductivities are *** high-potential compositions of Mg-Zn-Y-Zr alloys were selected by phase composition and their freezing ranges calculated using Thermo-Calc *** alloys were prepared,and their fluidity,hot tearing susceptibility,mechanical properties,and thermal conductivity were obtained and *** alloy composed of Mg-4 wt%Zn-3 wt%Y-0.3 wt%Zr was selected for further investigation,because of its high thermal conductivity and satisfactory mechanical *** Mg-4 wt%Zn-3 wt%Y-0.3 wt%Zr alloy’s fluidity and hot tearing susceptibility were similar to those of the widespread AZ91 commercial casting magnesium *** influence of a heat treatment regime on the microstructure,thermal conductivity,and mechanical properties of the developed alloy was also *** was established that the room temperature thermal conductivity of the Mg-4 wt%Zn-3 wt%Y-0.3 wt%Zr alloy after aging at 300℃for 5 h was 105 W/m K^(-1).Additionally,the following tensile test results were obtained in aged condition:120 MPa yield strength,200 MPa ultimate tensile strength,and 4%*** utilization of solid solution heat treatment at 520℃for 8 h prior to aging can promote up to 9%increase in *** Mg-4 wt%Zn-3 wt%Y-0.3 wt%Zr casting alloy can be used as a high thermal conductivity material with industrial applications.

关键词： Magnesium alloy Mg-Zn-Y-Zr Thermal conductivity Phase composition Fluidity Hot tearing susceptibility