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Effect of substrate and Annealing Temperatures on Mechanical Properties of Ti-rich NiTi Films

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Journal of Materials science & Technology 2010年第11期26卷 961-966页

作者： A.Kumar s.K.sharma s.Bysakh s.v.Kamat s.Mohan Defence Metallurgical Research Laboratory Department of Instrumentation Indian Institute of Science Central Glass and Ceramics Research Institute

The effect of substrate and annealing temperatures on mechanical properties of Ti-rich NiTi films deposited on si （100） substrates by DC magnetron sputtering was studied by *** films were deposited at two substrate temperatures viz.300 and 400 ℃.NiTi films deposited at 300 ℃ were annealed for 4 h at four different temperatures,i.e.300,400,500 and 600 C whereas films deposited at 400 ℃ were annealed for 4 h at three different temperatures,i.e.400,500 and 600 ℃.The elastic modulus and hardness of the films were found to be the same in the as-deposited as well as annealed conditions for both substrate *** a given substrate temperature,the hardness and elastic modulus were found to remain unchanged as long as the films were ***,both elastic modulus and hardness showed an increase with increasing annealing temperature as the films become *** results were explained on the basis of the change in microstructure of the film with change in annealing temperature.

关键词： NiTi thin film Annealing Nanoindentation

Cross-method Analysis of Corotation Radii Data set for spiral Galaxies

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Research in Astronomy and Astrophysics 2024年第7期24卷 95-110页

作者： v.s.Kostiuk A.A.Marchuk A.s.Gusev sternberg Astronomical Institute Lomonosov Moscow State UniversityUniversitetsky pr.13119234 MoscowRussia Central(Pulkovo)Astronomical Observatory Russian Academy of SciencesPulkovskoye chaussee 65/1196140 St.PetersburgRussia saint Petersburg state University Universitetsky pr.28198504 St.PetersburgRussia

A corotation radius is a key characteristic of disk galaxies that is essential to determine the angular speed of the spiral structureΩ_p,and therefore understand its *** the literature,there are plenty of methods to estimate this value,but do these measurements have any consistency?In this work,we collected a data set of corotation radius measurements for 547 galaxies,300 of which had at least two *** initial analysis reveals that most objects have rather inconsistent corotation radius ***,a significant fraction of galactic disks is distinguished by a large error coverage and almost uniform distribution of *** findings do not have any relation to spiral type,Hubble classification,or presence of a *** other reasons,obtained results could be explained by the transient nature of spirals in a considerable part of *** have made our collected data sample publicly available,and have demonstrated on one example how it could be useful for future research by investigating a winding time value for a sample of galaxies with possible multiple spiral arm patterns.

关键词： galaxies fundamental parameters-galaxies kinematics and dynamics-galaxies structure

Anode Plasma Electrolytic saturation of Titanium Alloys with Nitrogen and Oxygen

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Journal of Materials science & Technology 2016年第10期32卷 1027-1032页

作者： P.N.Belkin s.A.Kusmanov A.v.Zhirov v.s.Belkin v.I.Parfenyuk Nekrasov Kostroma state University 1 May14Kostroma 156961Russia

In this work, we investigated the features of the anode plasma electrolytic saturation of titanium alloys with nitrogen and oxygen. In this case, the titanium samples may be heated to 1050 ℃ using aqueous solutions of ammonium chloride as working electrolyte. The weight of titanium samples is found to change due to their oxidation and anode dissolution. An X-ray diffractometer, a scanning electron microscope,nuclear proton backscattering and an optical microscope were used to characterize the phase and elemental composition of the modified layer. The electrolyte composition（10 wt% ammonium chloride, 5wt% ammonia） and processing mode（850 ℃, 5 min） of commercially pure titanium（CP-Ti） allowing to obtain the hardened surface layer up to 0.1 mm with microhardness of 220 Hv were proposed. surface roughness Ra of samples after their nitriding for 5 min at 800 ℃ decreases from 1.67 to 0.082 μm. The anode plasma electrolytic nitriding could decrease friction coefficient and increase wear resistance of the CP-Ti. It is found that the anodic nitriding of low alloy titanium alloys reduces their corrosion rate in an aqueous solution of sulphuric（4.5%） and salt（0.2%） acids by 2 orders of magnitude. Results of cyclic testing show that anodic nitriding of commercial titanium leads to a decrease in corrosion rate by 8 times in solution of hydrochloric acid（6%） with addition of protein and vitamin.

关键词： Plasma electrolysis Titanium Nitriding Wear Corrosion

Effect of types of reinforcement on plastic hinge rotation parameters of RC beams under pushover and cyclic loading

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Earthquake Engineering and Engineering vibration 2015年第3期14卷 503-516页

作者： v.v.s.surya Kumar Dadi Pankaj Agarwal Department of Civil Engineering Institute of Technology Guru Ghasidas Vishwavidyalaya Bilaspur (C.G.) India Assistant Professor Department of Earthquake Engineering Indian Institute of Technology Roorkee

Experimental evaluation of reinforced concrete beam specimens with different characteristics of reinforcement subjected to pushover and cyclic loading is *** hinge rotation parameters are determined based on the idealization of pushover and hysteresis curves of reinforced concrete beam specimens constructed in two percentage of reinforcement(0.471%and 0.71%) with different ductile *** experimental test results provide a clear demarcation of the effect of types of loading and the types of reinforcement on the nonlinear performance characteristics of beam *** results are helpful to update the nonlinear modeling parameters of beam components for the specific type of reinforcement used in the construction of a *** updated non-linear modeling parameters of beam components in lumped plasticity model are compared with the values of AsCE/sEI 41-06(2007) used for the performance based design of structures.

关键词： concrete structures pushover loads cyclic loads hy

Merging bound states in the continuum in an open acoustic resonator

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science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang Bin Jia Artem s.Pilipchuk sibo Huang Chen shen Almas F.sadreev Yong Li Andrey E.Miroshnichenko school of Physics and Electronic sciences East China Normal University Institute of Acoustics Tongji University L.v.Kirensky Institute of Physics Department of Mechanical Engineering Rowan University school of Engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and Friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonHermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of Fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances

Toluene Alkylation with Methanol to p-Xylene over Heteropoly Acids supported by Clay

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Journal of Natural Gas Chemistry 2007年第1期16卷 42-45页

作者： v.v.Bokade s.s.Deshpande R.Patil s.Jain G.D.Yadav Catalysis Division National Chemical LaboratoryPune-411008India University Institute of Chemical Technology Mumbai-19India

The alkylation of toluene with methanol for the selective formation of p-xylene was systematically studied. very few studies have been reported on the use of superacids such as heteropolyacids on cheap supports, such as clay. This article deals with the use of different heteropoly acids （HPAs）, viz, Dodeca-Tungstophosphoric acid [***2O] （TPA）, Dodeca-Molyhdo phosphoric acid ammonium salt hydrate [H12Mo12N3O40P＋aq] （DMAA）, Dodeca-Molyhdo Phosphoric acid （PMA） on clay （MontmoriUonite, K-10） and as such plain clay. This comparative study reveals that 20%PMA/Clay shows 62% toluene conversion and 100% selectivity toward p-xylene.

关键词： toluene methanol p-xylene heteropoly acid clay

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

structural, vibrational, optical, photoluminescence, thermal,dielectric, and mechanical studies on zinc(tris) thiourea sulfate single crystal: A noticeable effect of organic dye

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Chinese Physics B 2018年第5期27卷 304-312页

作者： Mohd shkir v Ganesh s AlFaify I s Yahia Mohd Anis Advanced Functional Materials & Optoelectronic Laboratory Department of PhysicsFaculty of ScienceKing Khalid University Department of Physics Sant Gadge Baba Amravati University

In this work, uranine-dyed zinc（tris） thiourea sulfate（ZTs） monocrystals, 26 mm×15 mm×10 mm in size, were synthesized by the solution method at ambient temperature. Their purity, crystallinity, lattice parameters, and functional modes were studied by x-ray diffraction, Fourier transform-infrared spectroscopy（FT-IR）, and FT-Raman spectroscopy analyses. The sodium ion content of the crystals from the dye was confirmed by elemental analysis. The diffused reflectance spectral analysis of the dyed crystal revealed a characteristic absorption band at 490 nm attributed to the presence of the dye. The calculated band gaps of the non-dyed and dyed crystals were 4.53 and 4.57 e v, respectively. A green emission peak at ～（512 ± 4） nm was observed in the photoluminescence spectrum of the uranine-dyed crystals. A differential scanning calorimetry study confirmed that the thermal stability improved owing to the addition of the dye. Dielectric and microhardness studies were conducted to examine the significant improvements in the corresponding properties of dyed crystals. The results demonstrated the competency of the dyed ZTs crystals for applications in optoelectronic devices.

关键词： crystal growth dielectric properties luminescence thermal properties mechanical properties

Arctic source for elevated atmospheric mercury(Hg^0) in the western Bering sea in the summer of 2013

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Journal of Environmental sciences 2018年第6期30卷 114-121页

作者： v.v.Kalinchuk v.F.Mishukov A.s.Astakhov v.I.Il'ichev Pacific Oceanological Institute of Far Eastern Branch of Russian Academy of sciences Vladivostok Russia

Measurements of gaseous elemental mercury（Hg^0） in the marine boundary layer of the western Bering sea were performed using an automatic mercury analyzer RA 915 ＋（Ltd. ＂Lumex＂, st. Petersburg, Russia） aboard the Russian research vessel Academician *** from 3 to 20 August 2013. Hg^0 concentrations varied from 0.3 to 2.1 ng/m^3（n = 4783）;the average value（1.1 ± 0.3 ng/m^3） was lower than both the background range of the Northern Hemisphere（1.5–1.7 ng/m^3） and average values previously observed in the Bering sea, and corresponded to the background concentrations of the southern Hemisphere（1.1–1.3 ng/m^3）.Maximum Hg^0 concentrations were observed within air masses that came from the lower troposphere of the central Arctic. Under these conditions, Hg^0 ranged between 1.1 and 2.1 ng/m^3 with an average of 1.5 ± 0.2 ng/m^3（n = 1183）. Except for these periods, Hg^0 concentrations during the rest of the study varied from 0.3 to 1.8 ng/m^3, with an average value of 1.0 ± 0.2 ng/m^3（n = 3600）. Our results support the hypothesis that, in the summer, air masses from the central Arctic Ocean can be an exporter of mercury to lower latitudes. Perhaps the atmospheric transport of elevated concentrations of Hg^0 into lower latitudes may have implications for the biologic and economic health of important fisheries, such as the Bering sea.

关键词： Mercury Atmosphere Long-range transport Bering sea Arctic