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Chinese Journal of Chemistry 2004年第10期22卷 1196-1199页

作者： PARIHAR J.A RAmANA m.m.v Department of Chemistry University of Mumbai Santacruz (E) Mumbai-400098 IndiaDepartment of Chemistry University of Mumbai Santacruz (E) Mumbai-400098 India

The synthesis of the title compounds starting with the chemoselective dehydrogenation of 3-[2-(3,4-dihydro-1-naphthalenyl)ethyl]imidazolidine-2,4-diones has been described.

关键词： chemoselective dehydrogenation imide reduction intramolecular cyclization 13,16-diazasteroid

Erosion corrosion control of 6061 aluminum alloy in multi-phase jet impingement conditions with eco-friendly green inhibitor

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Chinese Journal of Chemical Engineering 2020年第2期28卷 340-347页

作者： m.Lavanya v.Ramachandra murthy Padmalatha Rao Department of Biotechnology Manipal Institute of TechnologyManipal Academy of Higher EducationManipalKarnatakaIndia Department of Chemistry Manipal Institute of TechnologyManipal Academy of Higher EducationManipalKarnatakaIndia

Erosion corrosion performance of 6061 aluminum alloy in simulated sea water slurry was investigated under multi-phase jet impingement conditions. The main objective of the work is to study erosion–corrosion of a material with engineering application and mitigate it using eco-friendly green inhibitor. Experiments were performed with the sand concentration of 0.3% and 0.3 μm size. The effect of temperature and flow rate on the performance of inhibitor was explored. Electrochemical methods were adopted for erosion-corrosion measurements. Experiments revealed that starch could mitigate erosion-corrosion with a maximum reduction efficiency of 58% at temperature of 303 K and flow rate of 4 L·min–1. Inhibition efficiency decreased with increase in flowrate and temperature. EIS spectrum demonstrated that the corrosion process in the presence on inhibitor was both charge transfer and mass transfer controlled. A key role of hydrodynamics in the performance of corrosion inhibitor was confirmed by the present study.

关键词： Erosion-corrosion Green-inhibitor Electrochemical studies Aluminum alloy Simulated sea water

A photometric study of two neglected eclipsing binaries

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Research in Astronomy and Astrophysics 2021年第7期21卷 192-198页

作者： v.Kudak m.Fedurco v.Perig S.Parimucha Laboratory of Space Researches Uzhhorod National UniversityUzhhorodDaleka Str.2A88000Ukraine Institute of Physics Faculty of ScienceUniversity of P.J.SafarikKosicePark Angelinum 904001Slovakia

We present the first BvR photometry,period variation and photometric light curve analysis of two poorly studied eclipsing binaries,v1321 Cyg and CR *** were carried out from November 2017 to January 2020 at the observatory of Uzhhorod National *** variations were studied using all available early published as well as our minima *** used the newly developed ELIS a code for the light curve analysis and determination of photometric parameters for both *** found that v1321 Cyg is a close detached eclipsing system with a low photometric mass ratio of q=0.28 which suggests that the binary is a post-mass transfer *** significant period changes in this system are *** Tau is,on the other hand,a semi-detached system where the secondary component almost fills its Roche *** detected a long-term period increase at a rate of 1.49 × 10^(-7) d yr^(-1),which supports mass transfer from the lower mass secondary component to the more massive primary.

关键词： binaries:close binaries:eclipsing stars:individual(v1321 Cyg CR Tau)

Photoelectrochemical activity of ZnO:Ag/rGO photo-anodes synthesized by two-steps sol-gel method

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Chinese Physics B 2022年第5期31卷 691-702页

作者： D Ben Jemia m Karyaoui m A Wederni A Bardaoui m v martinez-Huerta m Amlouk R Chtourou Laboratory of Nanomaterials and Renewable Energy Systems LANSER Research and Technology Center of EnergyBorj-Cedria Science and Technology ParkBP 952050 Hammam-LifTunisia Faculty of Science of Tunis University of Tunis El ManarTunisia Laboratory of Physics of materials and Nanomaterials Applied to the Environment(LaPhymNE) Faculty of Sciences of GabesCite ErriadhUniversity of Gabes6079 GabesTunisia lnstitute of Catalysis and Petrochemistry CSICin MadridSpain Laboratory of Nanomaterials Nanotechnology and Energy(L2NE)University of Tunis El ManarTunisia

This work investigated the influence of silver plasmon and reduced graphene oxide(r GO)on the photoelectrochemical performance(PEC)of Zn O thin films synthesized by the sol-gel *** physicochemical properties of the obtained photo-anodes were systematically studied by using several characterization *** x-ray diffraction analysis showed that all samples presented hexagonal wurtzite structure with a polycrystalline *** and energy dispersive x-ray(EDX)studies confirmed the existence of both Ag and r GO in Zn O:Ag/r GO thin *** estimated grain size obtained from scanning electron microscopy(SEm)analysis decreased with Ag doping,then increased to a maximum value after r GO *** Uv-vis transmission spectra of the as-prepared Zn O:Ag and Zn O:Ag/r GO thin films have shown a reduction in the visible range with a redshift at the absorption *** bandgaps were estimated to be around 3.17 e v,2.7 e v,and 2.52 e v for Zn O,Zn O:Ag,and Zn O:Ag/r GO,***,the electrical measurements revealed that the charge exchange processes were enhanced at the Zn O:Ag/r GO/electrolyte interface,accompanied by an increase in the(PEC)performance compared to Zn O and Zn O:Ag ***,the photocurrent density of Zn O:Ag/r GO(0.2 m A·cm^(-2)) was around 4 and 2.22 times higher than photo-anodes based on undoped Zn O(0.05 m A·cm^(-2)) and Zn O:Ag(0.09 m A·cm^(-2)),***,from the flat band potential and donor density,deduced from the mott-Schottky,it was clear that all the samples were n-type semiconductors with the highest carrier density for the Zn O:Ag/r GO photo-anode.

关键词： zinc oxide reduced graphene oxide silver doping sol-gel photoelectrochemical performance

Reduction of friction by normal *** of contact stiffness

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Friction 2017年第1期5卷 45-55页

作者： m.POPOv v.L.POPOv N.v.POPOv Berlin University of Technology Berlin 10623 GermanyTomsk Polytechnic University Tomsk 634050 RussiaTomsk State University Tomsk 634050 Russia Berlin University of Technology Berlin 10623 Germany

The present paper is devoted to a theoretical analysis of sliding friction under the influence of oscillations perpendicular to the sliding *** contrast to previous works we analyze the influence of the stiffness of the tribological contact in detail and also consider the case of large oscillation amplitudes at which the contact is lost during a part of the oscillation period,so that the sample starts to 'jump'.It is shown that the macroscopic coefficient of friction is a function of only two dimensionless parameters-a dimensionless sliding velocity and dimensionless oscillation *** function in turn depends on the shape of the contacting *** the present paper,analysis is carried out for two shapes:a flat cylindrical punch and a parabolic *** we consider 'stiff systems',where the contact stiffness is small compared with the stiffness of the *** role of the system stiffness will be studied in more detail in a separate paper.

关键词： sliding friction out-of-plane oscillation contact stiffness coefficient of friction active control of friction

Design of mg-Zn-Si-Ca casting magnesium alloy with high thermal conductivity

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Journal of magnesium and Alloys 2020年第1期8卷 184-191页

作者： v.E.Bazhenov A.v.Koltygin m.C.Sung S.H.Park A.Yu.Titov v.A.Bautin S.v.matveev m.v.Belov v.D.Belov K.v.malyutin National University of Science and Technology“mISiS” Leninskiy pr.4Moscow 119049Russia LG Electronics Inc. Yeoui-daeroYeongdeungpo-gu.128LG Twin TowerSeoul 07336 Republic of Korea

magnesium alloys are commonly used to produce lightweight *** most magnesium alloys exhibit low thermal conductivities,high thermal conductivities are needed for electronic *** this study,we attempted to develop new magnesium casting alloys with high thermal *** mg-Zn-Si-Ca alloy compositions were chosen using CALPHAD(CALculation of PHAse Diagrams)calculations,and alloy samples were *** fluidity and hot-tearing resistance were *** results indicated that these properties were similar to those of AZ91 *** tests showed that high-pressure die casting could produce mg-Zn-Si-Ca alloys possessing mechanical properties 1.5-3 times higher than those produced via sand *** alloy thermal conductivity was 126 W/mK at room *** corrosion rates of the as-cast samples in NaCl/water solutions were two times higher than that of AZ91.

关键词： magnesium alloy Thermal conductivity Phase composition Corrosion rate Sand casting High-pressure die casting

Photon interaction with semiconductor and scintillation detectors

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Nuclear Science and Techniques 2016年第3期27卷 159-170页

作者： v.p.singh n.m.badiger Department of Physics Karnatak UniversityDharwad 580003India

mass attenuation coefficients,effective atomic numbers,and electron densities for semiconductor and scintillation detectors have been calculated in the photon energy range 1 kev-100 *** interaction parameters have been found to vary with detector composition and the photon *** variation in the parameters with energy is shown graphically for all the partial photon interaction *** effective atomic numbers of the detector were compared with the ZXCOm program,and the results were found to be *** of semiconductor and scintillation detectors are presented in terms of effective atomic *** study should be useful for comparing the detector performance in terms of gamma spectroscopy,radiation sensitivity,radiation measurement,and radiation *** results of the present investigation should stimulate research work for gamma spectroscopy and radiation measuring materials.

关键词：相互作用参数闪烁探测器半导体光子有效原子序数光谱探测器质量衰减系数能量变化

Evaluation of influence of cold atmospheric pressure argon plasma operating parameters on degradation of aqueous solution of Reactive Blue 198(RB-198)

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Plasma Science and Technology 2020年第5期22卷 114-125页

作者： K NAvANEETHA PANDIYARAJ D vASU P v A PADmANABHAN m PICHUmANI R R DESHmUKH v KANDAvELU Research Division of Plasma Processing(RDPP) Department of PhysicsSri Shakthi Institute of Engineering and TechnologyChinniyam Palayam(post)Coimbatore-641062India Department of Nanoscience and Technology Sri Ramakrishna Engineering CollegeCoimbatore-641022India Department of Physics Institute of Chemical TechnologyMatungaMumbai 400019India Department of Chemistry Sri Shakthi Institute of Engineering and TechnologyL&T bypassChinniyam Palayam(post)Coimbatore-641062India

The intention of this work is to remove Reactive Blue 198(RB-198)dye components from simulated water solution using cold atmospheric pressure argon plasma *** solutions of RB-198 dye were treated as a function of various operating parameters such as applied potential,reaction time and distance between the plasma jet and surface of the *** efficiency of the degradation of RB-198 molecules was explored by means of Uv-vis *** reactive species involved during the treatment process were examined by optical emission spectra(OES).The present hydroxyl radicals(OH·radical)and hydrogen peroxide(H2O2)in the plasma-treated aqueous dye solutions were investigated using various spectroscopic *** other parameters such as total organic carbon(TOC),conductivity and p H were also *** toxicity of plasma-treated RB-198 solution was finally studied by diffusion bacterial analysis and by tracking seed germination *** results show that a higher degradation percentage of99.27%was acquired for the RB-198 treated at higher reaction time and applied potential,and shorter distance between the plasma jet and water *** may be due to the formation of various reactive oxygen(OH·radical,atomic oxygen(O)and H2O2)and nitrogen species(nitric oxide(NO)radicals and N2 second positive system(N2 SPS))during the processes as confirmed by OES analysis and other spectroscopy ***(17.7%-81.8%)and pH(7.5-3.4)values of the plasma-treated RB-198 decreased significantly with respect to various operation parameters,which indicates the decomposition of RB-198 molecules in the aqueous ***,the conductivity of plasma-treated RB-198 aqueous solutions was found to have increased linearly during the plasma treatment due to the formation of various ionic species in aqueous *** toxicity analysis clearly exhibits the non-toxic behavior of plasma-treated RB-198 aqueous solution towards the bacterial growth and germination of see

关键词： RB-198 degradation non-toxicity cold atmospheric pressure plasma jet

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

Post-Late Paleozoic Collisional Framework of Southern Great Altai

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Acta Geologica Sinica(English Edition) 2012年第5期86卷 1093-1104页

作者： Boris m. CHIKOv Sergei v. ZINOvIEv Еugene v. DEYEv Institute of Geology Siberian Branch of Russian Academy of Sciences Novosibirsk 630090 Russia

We outline the post-Late Paleozoic （latest Permian to Cenozoic） collisional framework of the southern Great Altai （Central Asia） produced by the convergence between the Tuva-mongolia and Junggar continental terranes （microplates）. The collisional structures in the region classified on the basis of their geometry and deformation style, dynamic metamorphism, and compositions of tectonites are of three main types：（1） mosaic terranes made up of large weakly deformed Paleozoic blocks separated by younger shear zones; （2） contractional deformation systems involving structures formed in post-Late Paleozoic time, parallel faults oriented along collisional deformation systems, and relict lenses of Paleozoic orogenic complexes; and （3） isolated zones of dynamic metamorphism composed mostly of collisional tectonites different in composition and alteration grade.

关键词： continental collision post-Late Paleozoic events tectonic framework dynamic metamorphism Altai Central Asia