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Clarifying the influence of albumin on the initial stages of magnesium corrosion in Hank's balanced salt solution

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Journal of Magnesium and Alloys 2021年第3期9卷 805-817页

作者： Di Mei Cheng Wang Sviatlana v.lamaka Mikhail l.Zheludkevich Magnesium Innovation Centre-MagIC Institute of Materials ResearchHelmholtz-Zentrum GeesthachtGeesthacht 21502Germany Institute for Materials Science Faculty of EngineeringKiel UniversityKiel 24103Germany

The corrosion behavior of Mg,a promising biodegradable metallic material,in protein-containing pseudophysiological environment is still not fully *** this work,the influence of albumin on the corrosion behavior of commercially pure magnesium(CP Mg)is investigated during short-term tests in Hank’s Balanced Salt Solution(HBSS).This work focuses on the reactions at the Mg/medium interface from the perspective of the interactions among albumin,media components and *** evolution tests demonstrate that the physiological amount of albumin(40 g l^(-1))accelerates Mg corrosion in HBSS during the first few hours but slows down the degradation *** presence of albumin decreases the concentration of free Ca^(2+)in HBSS and delays formation of protective co-precipitation products on Mg *** evolution of local pH(differs from typically monitored bulk pH)near Mg/medium interface in albumincontaining HBSS is reported for the first *** of local and bulk pH values elucidates the pH buffering effect of albumin during the immersion *** on these results,adsorption,chelating and pH buffering effects are summarized as three important aspects of albumin influence on Mg ***,constant replenishment of medium components is shown to be an influential factor during the Mg corrosion tests.

关键词： Magnesium Corrosion Albumin Biodegradable local pH

Fully Kinetic, Electromagnetic Particle-in-Cell Simulations of Plasma Microturbulence

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Communications in Computational Physics 2007年第4期2卷 684-722页

作者： J.l.v.lewandowski l.E.Zakharov Plasma Physics laboratory Princeton UniversityP.O.Box 451PrincetonNJ 08543USA.

A novel numerical method,based on physical intuition,for particle-in-cell simulations of electromagnetic plasma microturbulence with fully kinetic ion and electron dynamics is *** method is based on the observation that,for lowfrequency modes of interest[ω/ω_(ci)≪1,ωis the typical mode frequency andωci is the ion cyclotron frequency]the impact of particles that have velocities larger than the resonant velocity,v^(r)∼ω/k_(||)(k_(||) is the typical parallel wavenumber)is negligibly small(this is especially true for the electrons).Therefore it is natural to analytically segregate the electron response into an adiabatic response and a nonadiabatic response and to numerically resolve only the latter:this approach is termed the splitting ***,the exact separation between adiabatic and nonadiabatic responses implies that a set of coupled,nonlinear elliptic equations has to be solved;in this paper an iterative technique based on the multigrid method is used to resolve the apparent numerical *** is shown that the splitting scheme allows for clean,noise-free simulations of electromagnetic drift waves and ion temperature gradient(ITG)*** is also shown that the advantage of noise-free kinetic simulations translates into better energy conservation properties.

关键词： Plasma micro-turbulence particle-in-cell simulation multigrid solver.

Elaboration of a conceptual solution for the development of the Arctic shelf from seasonally flooded coastal areas

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International Journal of Mining Science and Technology 2022年第1期32卷 113-119页

作者： vladimir S.litvinenko Mikhail v.Dvoynikov vladimir l.Trushko Saint-Petersburg Mining University Saint-Petersburg 199106Russia

Currently,construction of facilities in the Arctic is carried out on sand islands,but there are limitations for remote coastal *** restrictions are associated with the lack of quarries with construction sand in the immediate vicinity of the work site,as well as the risk of seasonal flooding of the *** article includes conceptual solutions for construction of modular piling in Arctic nearshore conditions,upon which drilling rigs and auxiliary equipment can be placed for the purpose of subsequent wildcatting,development and exploratory extended reach drilling wells(with measured depth about 15000 m).During the construction of the modular piling foundations,a mathematical simulation of the thermodynamic condition of the frozen ground was conducted,and the bearing capacity of the foundations was *** proposed solutions will solve these problems by constructing modular pile foundations and placing the necessary infrastructure on them,taking into account the distribution of loads during operation in seasonally flooded areas.

关键词： Drilling&drillholes Stress analysis Offshore engineering Infrastructure planning Geotechnical engineering Extended reach drilling

Bending sensor based on flexible spin valve

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Chinese Physics B 2023年第5期32卷 655-661页

作者： l I Naumova R S Zavornitsyn M A Milyaev N G Bebenin A Y Pavlova M v Makarova I K Maksimova v v Proglyado A A Zakharov v v Ustinov M.N.Miheev Institute of Metal Physics Ural BranchRussian Academy of SciencesS.Kovalevskoi Street 18Ekaterinburg 620990Russia

Flexible spin valves were prepared by magnetron sputtering on polyimide substrates. The buffer layer that reduces significantly the effect of the polymer substrate on the spin valve microstructure and magnetoresistive properties was revealed. Bending deformation was applied to the microobjects based on the flexible spin valves in parallel to anisotropy axes. It was revealed that during the bend the magnetoresistance changes due to the joint impact of both the change of the magnetic field projection on the film plane and the change of the magnetic properties of the ferromagnetic layers. The obtained dependences have been used in construction of bending sensor, in which the flexible spin valve microstripes were united into the Wheatstone bridge.

关键词： spin valve polymer substrate magnetostriction magnetic anisotropy

Poling Effects of Dielectric and Optical Properties on Pb(Zn1/3Nb2/3)1-xTixO3 Crystal

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Journal of Rare Earths 2006年第z1期24卷 166-168页

作者： Tu Chi Shun Wang Fu Tang Chien R R Hugo Schmidt v Chew l l Graduate Inst.of Applied Science and Engineering Fu Jen University Taipei 242 China Graduate Inst.of Applied Science and Engineering Fu Jen University Taipei 242 China Department of Physics Montana State University Bozeman MT 59717 USA Department of Physics Montana State University Bozeman MT 59717 USA Department of Mechanical Engineering National University of Singapore Singapore

Dipolar relaxation and dielectric/piezoelectric resonance in a (001)-cut Pb(Zn1/3Nb2/3)0.9Ti0.1O3 (PZNT10%) single crystal before and after electric (E)-field poling were presented. Dielectric permittivities were measured as functions of temperature, frequency and poling E-field strength. Frequency-dependent dielectric spectroscopy in the poled sample exhibits multiple piezoelectric resonances between 0.1 and 1 MHz, which can be described by the forced-damped-oscillator model. The resonant spectra show significant changes while phase transitions are taking place. The unpoled crystal shows almost no optical birefringence, indicating that the average structure symmetry is isotropic. Birefringence of the crystal is significantly enhanced by a prior E-field poling.

关键词： Pb(Zn1/3Nb2/3)1-xTixO3 dielectric permittivity phase transitions refractive indices

Studies on activity of various extracts of Mentha arvensis linn against drug induced gastric ulcer in mammals

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World Journal of Gastrointestinal Oncology 2009年第1期1卷 82-88页

作者： Ramesh l londonkar Pramod v Poddar Department of Studies and Research in Biotechnology Gulbarga University

AIM:To examine the antiulcerogenic effects of various extracts of Mentha arvensis linn on acid,ethanol and pylorus ligated ulcer models in rats and ***:various crude extracts of petroleum ether,chloroform,or aqueous at a dose of 2 g/kg po did not produce any signs or symptoms of toxicity in treated *** the pyloric ligation model oral administration of different extracts such as petroleum ether,chloroform and aqueous at 375 mg/kg po,standard drug ranitidine 60 mg/kg po and control group 1 Tween 80,5 ml/kg po to separate groups of Wister rats of either sex(n = 6) was *** acidity,ulcer number,scoring,incidence,area,and ulcer index were ***:There was a decrease in gastric secretion and ulcer index among the treated groups *** ether(53.4),chloroform(59.2),aqueous(67.0) and in standard drug(68.7) when compared to the negative *** the 0.6 mol/l HCl induced ulcer model in rats(n = 6) there was a reduction in ulcerative score in animals receiving petroleum ether(50.5),chloroform(57.4),aqueous(67.5) and ***(71.2) when compared to the negative *** the case of the 90 ethanol-induced ulceration model(n = 6) in mice,there was a decrease in ulcer score in test groups of petroleum ether(53.11),chloroform(62.9),aqueous(65.4) and standard drug ranitidine(69.7) when compared to the negative *** was found that pre-treatment with various extracts of Mentha arvensis linn in three rat/mice ulcer models ie ibuprofen plus pyloric ligation,0.6 mol/l HCl and 90 ethanol produced significant action against acid secretion(49.3 ± 0.49 vs 12.0 ± 0.57,P various extracts of Mentha arvensis linn showed highly-significant activity against gastric ulcers(37.1 ± 0.87 vs 12.0 ± 0.57,P lUSION:various extracts of Mentha arvensis linn.375 mg/kg body weight clearly shows a protective effect against acid secretion and gastric ulcers in ibuprofen plus pyloric ligation,0.6 mol/l HCl induced

关键词： Mentha arvensis Anti ulcer Gastroprotection Medicinal plant

Optical Emission Spectroscopic Study During the Evaporation of Aluminium in the Thermal Plasma Reactor

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Plasma Science and Technology 2010年第1期12卷 27-30页

作者： I.BANERJEE N.v.KUlKARNI S.KARMAKER v.l.MATHE S.v.BHORASKAR A.K.DAS Applied Physics Department Birla Institute of Technology Department of Physics University of Pune Department Bhabha Atomic Research Center

The oxidation of aluminium was studied using optical emission spectroscopy （OES） during the evaporation of aluminium in traces of oxygen in a thermal plasma reactor. The ratio of the measured line intensities of Al-O with that of Al follows the exact trend as of that obtained from the corresponding line intensities in X-ray diffraction spectra of the synthesized samples. In this paper the inherent capacity of emission spectroscopy in evaluating the growth processes under plasma induced reactions is presented.

关键词： thermal plasma reactor aluminium oxidation optical emission spectroscopy,X-ray diffraction

A neutronic experiment to support the design of an Indian TBM shield module for ITER

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Plasma Science and Technology 2019年第6期21卷 147-152页

作者： H l SWAMI M ABHANGI Sanchit SHARMA S TIWARI A N MISTRY v vASAvA v MEHTA S vAlA C DANANI v CHAUDHARI P CHAUDHURI Institute for Plasma Research Gandhinagar Gujarat 382428 India Homi Bhabha National Institute(HBNI) Anushaktinagar Mumbai 400094 India Pandit Deendayal Petroleum University Gandhinagar Gujarat 382007 India

A shield module is associated with an Indian Test Blanket Module (TBM) in ITER to limit the radiation doses in port inter-space *** shield module is made of stainless steel plates and water *** is identified as an important component for radiation protection because of its radiation exposure control *** radiation protection classification leads to more assurance of the component *** order to validate and verify the design of the shield module,a neutronic laboratory-scale experiment is designed and *** experiment is planned by considering the irradiation under a neutron source of 14 Mev and yields of 1010 n *** reference neutron spectrum of the ITER TBM shield module has been achieved through optimization of the neutron source spectrum by a combination of steel and lead *** neutron spectrum and flux are measured using a multiple foil activation technique and neutron dose-rate meter lB 6411 (He-3 proton recoil counter with polyethylene),*** neutronic design simulation is assessed using MCNP5 and FENDl 2.1 crosssection *** paper covers neutronic design,irradiation and the outcome of the experiment in detail.

关键词： TBM shield module neutronic experiment ITER MCNP neutron attenuation

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