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乌拉尔南部和印度南部地区隐晶质菱镁矿的地质与地球化学对比研究(英文)

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岩石学报 2004年第4期20卷 821-828页

作者： v PRASAnnAKUMAR M T KRUPEnIn T y gULyAEvA v g PETRISCHEvA Department of geology University of Kerala Kariavattom Trivandrum India 695 581Institute of Geology and Geochemistry Urals Branch of RAS Ekaterinburg RussiaInstitute of Geology and Geochemistry Urals Branch of RAS Ekaterinburg RussiaInstitute of Geology and Geochemistry Urals Branch of RAS Ekaterinburg Russia

印度南部和乌拉尔南部都有隐晶质菱镁矿产出,这两处矿床的产出地质环境相似,在矿物学和地球化学上具有广泛的相似性.印度南部的菱镁矿矿化主要与超镁铁质侵入杂岩体有关,并形成了部分已受变质的火山沉积地层.超镁铁质侵入杂岩体由纯橄岩... 详细信息

印度南部和乌拉尔南部都有隐晶质菱镁矿产出,这两处矿床的产出地质环境相似,在矿物学和地球化学上具有广泛的相似性.印度南部的菱镁矿矿化主要与超镁铁质侵入杂岩体有关,并形成了部分已受变质的火山沉积地层.超镁铁质侵入杂岩体由纯橄岩,橄榄岩,辉石岩,辉长岩及它们的变质产物组成.在乌拉尔地区,菱镁矿床位于一个蛇绿岩带上的超镁铁岩地体中.隐晶质菱镁矿就以网脉状产出于超镁铁质岩地体上部的风化带中.印度和乌拉尔两个地区的矿床中的矿物组合都有菱镁矿,石英,方解石和白云石,但在印度南部的矿区中还含有滑石和菱铁矿.两个地区的菱镁矿矿石的质量都很好,所有的样品的主要成分都为菱镁矿(73～96%),而方解石(1～3%),白云石(0～7%),菱铁矿(0～2%),石英(0～5%)和滑石(0～2%)都只是次要矿物.次生的白云石和菱铁矿使一些矿石含有较高的CaO(最高达2.6%)和FeO(最高达1.6%),石英和滑石等矿物则使矿石中的siO2较高(5～8%).滑石指示了低温成因,它的出现说明两个矿区的菱镁矿可能都是内生或外生的成矿流体在上升或下降的过程中在开放裂隙中沉淀而成的.本文研究表明,全球性的超镁铁岩中菱镁矿成矿事件与蛇绿岩带有关,这对菱镁矿的勘探有指导意义.

关键词：隐晶质菱镁矿滑石裂隙充填超镁铁岩蛇绿岩带印度南部和乌拉尔南部

High-temperature glassy-ceramic sealants siO_2-Al_2O_3-BaO-MgO and siO_2-Al_2O_3-ZrO_2-CaO-na_2O for solid oxide electrochemical devices

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Transactions of nonferrous Metals Society of China 2016年第11期26卷 2916-2924页

作者： S.QI n.M.POROTnIKOvA M.v.AnAnyEv A.v.KUZMIn v.A.EREMIn A.A.PAnKRATOv n.g.MOLCHAnOvA O.g.REZnITSKIKH A.S.FARLEnKOv E.g.vOvKOTRUB yu.P.ZAIKOv 北京化工大学材料科学与工程学院北京100029 Institute of High-Temperature Electrochemistry of UB RAS Ekaterinburg 620137Russia Ural Federal University named after the First President of Russia B.n.yeltsin Ekaterinburg 620002Russia

glasses of the siO_2-Al_2O_3-BaO-MgO and siO_2-Al_2O_3-ZrO_2-CaO-na_2O systems were synthesized in the perspective to apply them as sealants in SOFC at operating temperatures of 700-900 °C. Thermal properties of the chosen glass compositions and their compatibility with the SOFC materials(ySZ-electrolyte and alloy-interconnector Crofer22 APU, 15Х25Т) were investigated by means of synchronic thermal analysis and high-temperature dilatometry. The elemental analysis was performed by atomic emission spectroscopy. The average values of the temperature coefficients of the linear extension are 10.0×10^(-6) °С^(-1) for glass 45%siO_2-15%Al_2O_3-25%BaO-15%MgO and 9.5×10^(-6) °С^(-1) for glass 60%siO_2-10%Al_2O_3-10%ZrO_2-5%CaO-15%na_2O. The gluing microstructure in ySZ/glass/Crofer22 APU was studied by scanning electron microscopy. The crystallization process of silicate phases was revealed to occur in the siO_2-Al_2O_3-BaO-MgO glass. The analysis of the crystallization products was performed by Raman spectroscopy and X-ray diffraction. glassy ceramics was proved to possess better parameters in comparison with amorphous glass to be used as a sealant in electrochemical sensors and oxygen sensors. The siO_2-Al_2O_3-ZrO_2-CaO-na_2O low-temperature amorphous glass can be applied in SOFC.

关键词： glassy-ceramic sealants SOFC ySZ Crofer22APU magnesium silicate

浸渍硼氧化物改善柔性石墨的氧化稳定性和力学性能(英文)

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新型炭材料 2012年第1期27卷 12-18页

作者： D．v．Savchenko A．A．Serdan v．A．Morozov g．vanTendeloo S．g．Ionov DepaxtmentofChemistry MoscowStateUniversityMoscow119991Russia； EMAT UniversityofAntwerpGroenenborgerlaan171B-2020AntwerpBelgium

膨胀石墨经硼氧化物浸渍修后辊轧制成柔性石墨箔。应用激光质谱、X-光电子谱、扫描电镜和热重测定分析了所制柔性石墨箔。结果表明:浸渍硼氧化物后石墨箔的初始氧化温度提高了约150℃。即使浸渍少量(质量分数低于2%)的硼氧化物也能提高... 详细信息

膨胀石墨经硼氧化物浸渍修后辊轧制成柔性石墨箔。应用激光质谱、X-光电子谱、扫描电镜和热重测定分析了所制柔性石墨箔。结果表明:浸渍硼氧化物后石墨箔的初始氧化温度提高了约150℃。即使浸渍少量(质量分数低于2%)的硼氧化物也能提高此材料的拉伸强度。纵观其浸渍改善效果,可能归因于膨胀石墨粒中与石墨片层化学键合的硼氧化物堵塞了其活性位点所致。

关键词：膨胀石墨石墨箔硼氧化物氧化防护拉伸强度

Optimization of pulsed current gas tungsten arc welding process parameters to attain maximum tensile strength in AZ31B magnesium alloy

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Transactions of nonferrous Metals Society of China 2011年第3期21卷 467-476页

作者： g.PADMAnABAn v.BALASUBRAMAnIAn Center for Materials Joining and Research (CEMAJOR) Department of Manufacturing Engineering Annamalai University

An empirical relationship to predict tensile strength of pulsed current gas tungsten arc welded AZ31B magnesium alloy was developed. Incorporating process parameters such as peak current, base current, pulse frequency and pulse on time were studied. The experiments were conducted based on a four-factor, five-level, central composite design matrix. The developed empirical relationship can be effectively used to predict the tensile strength of pulsed current gas tungsten arc welded AZ31B magnesium alloy joints at 95% confidence level. The results indicate that pulse frequency has the greatest influence on tensile strength, followed by peak current, pulse on time and base current.

关键词： AZ31B magnesium alloy pulsed current gas tungsten arc welding response surface methodology optimization tensile strength

Effects of laser beam welding parameters on mechanical properties and microstructure of AZ31B magnesium alloy

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Transactions of nonferrous Metals Society of China 2011年第9期21卷 1917-1924页

作者： g.PADMAnABAn v.BALASUBRAMAnIAn Center for Materials Joining & Research Department of Manufacturing EngineeringAnnamalai University

The effects of laser beam welding process parameters such as laser power,welding speed and focal position on mechanical properties and microstructure of AZ31B magnesium alloy were *** joints were fabricated using different levels of laser power,welding speed and focal *** properties of the welded joints were evaluated and correlated with the weld zone microstructure and *** is found that the joints fabricated using a laser power of 2 500 W,welding speed of 5.5 m/min and focal position of-1.5 mm yield superior tensile properties compared with the other *** formation of very fine grains in weld region,higher fusion zone hardness and uniformly distributed finer precipitates are the main reasons for superior tensile properties of these joints.

关键词： laser beam welding magnesium alloy tensile properties laser power welding speed focal position

Separation and purification of tantalum from plumbomicrolite of amazonite deposit in Kola Peninsula by acid leaching and solvent extraction

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Journal of Central South University 2021年第1期28卷 72-88页

作者： S M MASLOBOEvA L g ARUTyUnyAn M n PALATnIKOv D v MAnUKOvSKAyA Tananaev Institute of Chemistry–Subdivision of the Federal Research Centre Kola Science Centre of the Russian Academy of SciencesApatity 184209Russia

A plumbomicrolite concentrate(PMC)was leached with the mixture of HF and H2SO4,HF and HnO3 acids,*** conditions ensuring high recovery of tantalum and niobium(up to 99%)into solution,and radionuclides into insoluble residue were ***-sulfuric acid and fluoride-nitric acid schemes were proposed for PMC leaching by an extractive separation of tantalum form niobium,lead and impurities,and production of high-purity tantalum ***-1 was used as an *** conditions for production of high-purity tantalum strip solutions were defined for all stages(extraction-scrubbing-stripping).Produced tantalum compounds,such as tantalum pentoxide and potassium heptafluotanthalate,comply with the norms for high-purity substances in terms of impurities *** choice of the PMC processing scheme is determined by its profitability.

关键词： mineral plumbomicrolite tantalum niobium acid leaching radioactivity solvent extraction

simulations of ALT-like explosive magnetic devices for ramp compression of materials by magnetically imploded liners

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Matter and Radiation at Extremes 2020年第4期5卷 16-22页

作者： A.M.Buyko g.g.Ivanova I.v.Morozova FSUE Russian Federal Nuclear Center–All-Russian Research Institute of Experimental Physics(RFNC-VNIIEF)SarovNizhny Novgorod RegionRussia

Revised simulations of ALT-like devices are *** results from these simulations closely match those from experiments and demonstrate the capabilities of the devices as applied to ramp compression of metals to pressures of 20 Mbar by imploding liners driven by∼10 Mg azimuthal magnetic fields(with currents up to 55 MA).These results can be applied to the design of experiments on isentropic compression of materials.

关键词： materials. magnetic simulation

Recovery of Lead from Sulfide Concentrate after Mechanochemical Activation Using nitric Acid

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Chinese Journal of Chemical Engineering 2005年第1期13卷 91-95页

作者： A.g.Kholmogorov O.n.Kononova g.L.Pashkov L.v.Shashina v.P.Plekhanov A.A.Sabetskiy Institute of Chemistry and Chemical Technology siberian Department of the Academy of Science Karl Marx Pr.42660049 KrasnoyarskRussia Department of Chemistry Krasnoyarsk State University Svobodny Pr.79660041 KrasnoyarskRussia

Decomposition of lead sulfide concentrates in nitric acidic solutions after ferric(Ⅲ)nitrate addition and mechanical preparation has been *** was found out that the decomposition can be achieved in HnO_(3) solution(>1.5 mol·L^(-1))at the temperature above 85℃.The leaching rate of lead can be increased by means of mechanochemical *** use of[Fe(nO_(3))_(3)-HnO_(3)-H_(2)O]aqueous salt system allows the decomposition of lead sulfide concentrate at room temperature and in this case the concentration of HnO_(3) does not exceed 0.05-0.1 mol.L^(-1),The degree of lead recovery into solution from PbS concentrate reaches 99.3%-99.6c70 with the mechanochemical activation of this *** insoluble residues after the leaching contain siO_(2),S^(0),FeCO_(3) and PbSO_(4).

关键词： lead sulfide concentrates nitric acidic solutions mechanochemicalactivation

Present status and future directions:Apexification

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World Journal of Methodology 2025年第1期15卷 26-32页

作者： Sachin Chauhan Radha Chauhan Prashant Bhasin Bhavna g Sharaf Department of Conservative Dentistry and Endodontics Sudha Rustagi College of Dental Sciences and ResearchFaridabad 121002HaryanaIndia Department of Prosthodontics and Crown and Bridge and Oral Implantology Mahatma Gandhi Dental College&HospitalJaipur 302022RajasthanIndia Department of Pedodontics and Preventive Dentistry Sudha Rustagi College of Dental Sciences and ResearchFaridabad 121002HaryanaIndia

The success rate of apexification is primarily determined by multiple factors,including the material used,the size of the open apex compared to the length of the root,and the technique used in each *** main objective of this review was to provide an update on the present management of open apex to identify factors and circumstances that may influence the success of apexification using different materials and *** research on apexification should focus on how to treat open apices with wide periapical lesions without ***,the predictability of these parameters with non-surgical procedures was uncertain,but now,with the use of a dental operating microscope,it has become more *** reason could be that extra visits are no longer required due to major advances in the armamentarium and materials used for apexification.

关键词： Bioceramics Magnification Biodentine Mineral trioxide aggregate Apexification Open apex