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Kaapvaal lamproite melts(aka orangeites):A new type of alkalicarbonate liquid?insights from olivine-hosted multiphase inclusions(silvery Home,south Africa)

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Geoscience Frontiers 2024年第5期15卷 308-322页

作者： Adam Abersteiner Alexey tarasov.Alexander Golovin Geoffrey H.Howarth Vadim s.Kamenetsky Department of Geosciences and Geography Research Programme of Geology and Geophysics(GeoHel)University of HelsinkiFinland Institute for sustainability Energy and ResourcesThe University of AdelaideAdelaide SA-5005Australia Department of Earth sciences School of Physical SciencesThe University of AdelaideAdelaide SA-5005Australia V.s.sobolev Institute of Geology and Mineralogy siberian Branch Russian Academy of SciencesRussia Department of Geological sciences University of Cape TownRondebosch 7701South Africa Center of Deep sea Research Institute of OceanologyChinese Academy of Sciences266071 QingdaoChina

Kaapvaal lamproites(aka orangeites)are a group of volatile-rich(H_(2)O,CO_(2)),micaceous,ultrapotassic igneous rocks that are unique to the Kaapvaal craton in southern ***,the composition of the melts that give rise to these rocks remains poorly understood due to overprinting effects of contamination by mantle and crustal material,volatile exsolution,fractional crystallisation and post-magmatic ***,this lack of reliable data on the initial composition of the Kaapvaal lamproite melts hampers our understanding of their source,petrogenesis and ascent *** is a common mineral comprising the Kaapvaal lamproites that has both xenocrystic(i.e.,mantle)and magmatic *** inclusions(melt/fluid)entrapped within olivine have been consistently demonstrated as an effective tool for gaining fundamental insights into the composition and evolution of melts that produce both kimberlites and lamproites,prior to processes,such as eruption,devolatization and syn-/post-magmatic *** this study,multiphase inclusions of both secondary and pseudosecondary origin hosted in olivine from a Kaapvaal lamproite(silvery Home,south Africa)provide novel insights into the composition of the melt(s)that initially transported olivine to the surface and then crystallised after emplacement to form the lamproite *** inclusions in our study contain daughter mineral assemblages consisting of diverse Ca-Mg carbonates,including K-,Na-,Ba-,and sr-bearing varieties,moderate K-rich silicates(phlogopite,tetraferriphlogopite),and subordinate oxides,phosphates,sulphides,sulphates,and *** on these daughter mineral assemblages,we suggest that the composition of the melt entrapped by olivine was siO_(2)-poor,Ca-Mg carbonate-rich and contained elevated concentrations of K,Na,Ba,sr,P and *** mineral and reconstructed melt compositions are in stark contrast to the mineral association of the groundmass and the bulk-rock composition

关键词： Lamproite Kaapvaal Multiphase inclusions Olivine Orangeite

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Fan‐hinged shear instead of frictional stick–slip as the main and most dangerous mechanism of natural,induced,and volcanic earthquakes in the earth's crust

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Deep Underground science and Engineering 2023年第4期2卷 305-336页

作者： Boris G.tarasov Laboratory of Geomechanics of Highly stressed Rock and Massives Far Eastern Federal UniversityVladivostokRussia

Frictional stick–slip instability along pre‐existing faults has been accepted as the main mechanism of earthquakes for about 60 years,since it is believed that fracture of intact rocks cannot reﬂect such features inherent in earthquakes as low shear stresses activating instability,low stress drop,repetitive dynamic instability,and connection with pre‐existing *** paper demonstrates that all these features can be induced by a recently discovered shear rupture mechanism(fan‐hinged),which creates dynamic ruptures in intact rocks under stress conditions corresponding to seismogenic *** key element of this mechanism is the fan‐shaped structure of the head of extreme ruptures,which is formed as a result of an intense tensile cracking process,with the creation of inter‐crack slabs that act as hinges between the shearing rupture *** preference of the fan mechanism over the stick–slip mechanism is clear due to the extraordinary properties of the fan structure,which include the ability to generate new faults in intact dry rocks even at shear stresses that are an order of magnitude lower than the frictional strength;to provide shear resistance close to zero and abnormally large energy release;to cause a low stress drop;to use a new physics of energy supply to the rupture tip,providing supersonic rupture velocity;and to provide a previously unknown interrelation between earthquakes and *** these properties make the fan mechanism the most dangerous rupture mechanism at the seismogenic depths of the earth's crust,generating the vast majority of *** detailed analysis of the fan mechanism is presented in the companion paper“New physics of supersonic ruptures”published in *** study of this subject is a major challenge for deep underground science,earthquake and fracture mechanics,volcanoes,physics,and tribology.

关键词： earthquake and rockburst mechanisms interrelation of earthquakes and volcanoes physics of supersonic ruptures postpeak rock properties rock rupture mechanism rupture energy budget

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New physics of supersonic ruptures

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Deep Underground science and Engineering 2023年第3期2卷 207-244页

作者： Boris G.tarasov Laboratory of Geomechanics of Highly stressed Rock and Massives Far Eastern Federal UniversityVladivostokRussia

Until recently,it is believed that the rupture speed above the pressure wave is impossible since spontaneously propagating ruptures are driven by the energy released due to the rupture motion,which is transferred through the medium to the rupture tip region at the maximum speed equal to the pressure wave ***,the apparent violation of classic theories has been revealed by new experimental results demonstrating supersonic shear *** paper presents a detailed analysis of the recently discovered shear rupture mechanism(fan hinged),which suggests a new physics of energy supply to the tip of supersonic *** key element of this mechanism is the fan‐shaped structure of the head of extreme ruptures,which is formed as a result of an intense tensile cracking process with the creation of intercrack slabs that act as hinges between the shearing rupture *** fan structure is featured with the following extraordinary properties:extremely low friction approaching zero;amplification of shear stresses above the material strength at low applied shear stresses;creation of a self‐disbalancing stress state causing a spontaneous rupture growth;abnormally high energy release;generation of driving energy directly at the rupture tip which excludes the need to transfer energy through the *** fan mechanism operates in intact rocks at stress conditions corresponding to seismogenic depths and in pre‐existing extremely smooth interfaces due to identical tensile cracking processes at these *** is Paper 1(of two companion papers)which discusses the fan theory and extreme ruptures in experiments on extremely smooth *** 2 entitled“Fan‐hinged shear instead of frictional stick‐slip as the main and most dangerous mechanism of natural,induced and volcanic earthquakes in the earth's crust”considers extreme ruptures in intact *** study of this subject is a major challenge for deep underground science,earthquake and fracture mechanics

关键词： fan‐hinged rupture mechanism laboratory earthquakes on extremely smooth interfaces physics of supershear and supersonic ruptures rupture energy budget

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Acoustic emission characterization of sliding wear under condition of direct and inverse transformations in lowtemperature degradation aged Y-TZP and Y-TZP-Al_2O_3

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Friction 2018年第3期6卷 323-340页

作者： Nikolai L sAVCHENKO Andrey V FILIPPOV sergei Yu tarasov.Andrey I DMITRIEV Evgeny V sHILKO Aleksandr s GRIGORIEV Institute of strength Physics and Materials science sB RAs National Research Tomsk Polytechnic University National Research Tomsk state University

In this research, results of the investigation of the sliding friction and wear of yttria-stabilized tetragonal zirconia polycrystalline(Y-TZP) and Y-TZP-Al_2O_3 samples preliminarily subjected to low-temperature degradation are reported. The investigation was carried out using a pin-on-disk tribometer with simultaneous recording of acoustic emission(AE) and vibration acceleration. The sliding wear process was found to be determined by dynamic direct and inverse Y-TZP transformations detected by monoclinic and tetragonal X-ray diffraction peak ratios. The AE signals generated under direct and inverse transformations can be used to characterize wear and friction mechanisms as well as direct and inversed sliding-induced phase transformations. The AE signal energy grows with the friction coefficient and the inverse transformation degree. Reduction of the AE signal energy indicates establishing the mild wear stage caused by effective stress-induced direct martensitic transformation. The AE signal median frequency increases in the case of lower friction. Numerical studies of wear subsurface fracture under conditions of stress-induced martensitic transformation were used to elucidate the role played by the phase transformation in Y-TZP and Y-TZP-Al_2O_3. Martensitic transformation in Y-TZP was described with use of the non-associated dilatant plasticity model. simulation results particularly show that increase in the value of dilatancy coefficient from 0 to 0.2 is accompanied by 25%-30% reduce in characteristic length and penetration depth of sliding-induced subsurface cracks. As shown the AE may be an effective tool for in-situ monitoring the subsurface wear of materials experiencing both direct and inverse transformations.

关键词： zirconia transformation toughening low-temperature degradation friction acoustic emission numerical modeling movable cellular automata method

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Emulsification for castor biomass oil

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Frontiers of Chemical science and Engineering 2011年第1期5卷 96-101页

作者： Dongxiang ZHANG Yuanping LIN Anmei LI V.V.tarasov school of Chemical Engineering and the Environment Beijing Institute of TechnologyBeijing 100081China D.I.Mendeleev University of Chemical Technology of Russia 125190 MoscowRussia

The effect of the emulsifier formula on the stability of castor oil-water system was studied through compounding three groups of emulsifiers from the aspects of stability factor of absorbance,centrifuge stability,demulsification time in quiescence,appearance of the droplets,and *** best emulsifier formula for castor biomass oil was the composite formula of sorbitan monooleate and polyoxyethylene sorbitan *** exists between the stability of emulsion and the viscosity/particle size of the droplets,with better stability in the case of greater viscosity or narrower distribution of particle size in the emulsion of castor oil-water *** added to the castor oil-water system may decrease the viscosity of the *** the castor oil-water emulsion with methanol-castor oil-water emulsion,the optimal hydrophilic and lipophilic balance(HLB)value based on castor oil-water system was acquired between 6.6 and 7.5,while the optimal HLB value based on the methanol-castor oil-water system was between 5.5 and *** optimal HLB value of methanolcastor oil-water system gradually moved to that of castor oil-water emulsion with adding more water.

关键词： castor oil biomass oil emulsification stability viscosity corrosivity

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Infl uence of fire on soil temperatures of pine forests of the middle taiga,central siberia,Russia

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Journal of Forestry Research 2021年第3期32卷 1139-1145页

作者： Irina Nikolaevna Bezkorovaynaya Pavel Albertovich tarasov.Irina Gennadievna Gette Irina Andreevna Mogilnikova siberian Federal University 79 SvobodnyKrasnoyarskRussia 660041 Reshetnev siberian state University of science and Technology 31 Krasnoyarsky Rabochy AvKrasnoyarskRussia 660037

Temperatures of sandy podzols of middle taiga pine forests with moss and lichen ground cover were analyzed which had been exposed to ground fires of low to medium *** general,temperatures in lichen and moss plots of the pine forests under study,are close to each similar,but in the first year after a fire a noticeable contrast was *** reasons are an increase in the amplitude of daily temperatures on the soil surface and stronger heating of upper mineral *** in the mineral layer with depths up to 30 cm depend on the thickness of the forest fl *** of the results show that the duration of postfire effects in pine forests with sandy podzols is determined by a number of factors:the intensity of the fire,the degree of erosion of the ground cover and litter,and the recovery rate of these components.

关键词： Ground fire Pine forests soil temperature

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Preparation and photocatalytic kinetics of nano-ZnO powders by precipitation stripping process

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Frontiers of Chemical science and Engineering 2008年第3期2卷 319-324页

作者： Dongxiang ZHANG Hang XU Min XUE Wenguo XU V tarasov school of Chemical Engineering and the Environment Beijing Institute of TechnologyBeijing 100081China school of science Beijing Institute of TechnologyBeijing 100081China D.I.Mendeleyev University of Chemical Technology of Russia 125190 MoscowRussia

Ultra-fine zinc oxalate powders were prepared through a precipitation stripping method with bis(2-ethylhexyl)phosphate(HDEHP)diluted by tetrachloride carbon as the extractant,and oxalic acid ethanol aqueous solution as the re-extractant and *** oxide powders were obtained by decomposing zinc oxalate powders at 450℃.The prepared zinc oxide powders were characterized by transmission electron microscope(TEM),scanning electron microscope(sEM),Thermogravimetric analysis(TG),X-ray diffraction(XRD)and Fourier transmission infrared(FT-IR)*** photocatalytic performance of methylene blue by zinc oxide was studied based on the Langmuir model and Photo-Layer *** results show that some zinc oxide powders were micro-multipore materials with hexagonal *** particle size was around 32 *** photocatalytic process was the control step in the chemical *** photo catalytic process followed pseudo-first order kinetics and NOH concentration inside the photo-layer in different reaction condition were calculated according to the Photo-Layer model.

关键词： precipitation stripping method ZnO photocatalysis kinetics

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Giant magnetoresistance in Fe/siO_2/p-si hybrid structure under non-equilibrium conditions

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Transactions of Nonferrous Metals society of China 2014年第10期24卷 3158-3163页

作者： N.V.VOLKOV A.s.tarasov.A.O.GUsTAJCEV O.N.VOLKOVA s.N.VARNAKOV s.G.OVCHINNIKOV Kirensky Institute of Physics Russian Academy of SciencesSiberian Branch Krasnoyarsk 660036 Russia Institute of Engineering Physics and Radio Electronics Siberian Federal University Krasnoyarsk 660041 Russia Institute of Engineering Physics and Radio Electronics Siberian Federal University Krasnoyarsk 660041Russia

The giant magnetoresistive（MR） effect was investigated in a simple Fe/si O2/p-si-hybrid-structure-based device from two back-to-back schottky diodes. The effect was revealed only under the non-equilibrium conditions caused by optical radiation. It is demonstrated that the magnetoresistance ratio attains 100 or more. The main peculiarity of the MR behavior is its strong dependence on the magnitude and the sign of the bias current across the device and, most surprisingly, upon polarity of the magnetic field. It is important that the magnetoresistive effect is implemented exclusively in the subsystem of minority charge carriers transferred to the non-equilibrium states. The development of magneto-sensitive devices of this type can give grounds for a novel direction of semiconductor spintronics.

关键词： magnetoresistance hybrid structure schottky diode

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Evidence for polarization-induced phase transformations and degradation in CH_(3)NH_(3)PbI_(3)

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Nano Research 2023年第7期16卷 9435-9442页

作者： Aleksei Yu.Grishko Maria A.Komkova Ekaterina I.Marchenko Alexandra V.Chumakova Alexey B.tarasov.Eugene A.Goodilin Andrei A.Eliseev Department of Materials science MSU-BIT UniversityShenzhen 517182China Department of Chemistry Lomonosov Moscow State UniversityMoscow 119991Russia Department of Materials science Lomonosov Moscow State UniversityMoscow 119991Russia European synchrotron Radiation Facility F-38042 GrenobleFrance

In solar cells,hybrid halide perovskites operate under constant bias,thus their stability towards electric field-induced degradation is of key *** we report on evidence of previously unidentified electric field-induced transitions and degradation path of CH_(3)NH_(3)PbI_(3)(MAPbI_(3))using elemental and phase *** films of MAPbI_(3) were deposited onto 1-2μm-pitch interdigitated electrodes and subjected to direct current(DC)-*** MAPbI_(3) layer polarized withs pronounced ion redistribution to methylammonium-rich MAPbI_(3)-y(yss of both methylammonium and iodine provokes degradation of MAPbI_(3).Using nanofocus grazing-incidence wide-angle X-ray scattering(GIWAXs),we unambiguously showed that the bias voltage induces the transformation ofβ-MAPbI_(3) to metastableδ-MAPbI_(3) polymorph via alignment of polar organic cation with the electric *** transformation is partially reversible upon field ***,once formed,δ-MAPbI_(3) disrupts the morphology of pristine film and undergoes decomposition toβ-MAPbI_(3)(β-MAPI)and PbI_(2).With the aforementioned compositional and phase changes,only MA-rich part serves as the charge separation layer,while the I-rich excitation is blocked with the PbI_(2) barrier serving as holes trapping *** observations reveal the intermediate steps in electric-field-driven degradation of halide perovskites and show the role of polar cations in the process,which is instructive for further material design with higher stability metrics.

关键词： halide perovskites stability degradation electric field ionic conductivity stoichiometry

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硫代杯[4]冠-4在硝酸体系中对sr^(2+)的萃取

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化工学报 2015年第3期66卷 1035-1041页

作者：李洁周丽娟张东翔刘聪 tarasov.V.V. 北京理工大学化工与环境学院北京100081 俄罗斯门捷列夫化工大学莫斯科125190

乏燃料后处理的高放废液分离过程中,发展新型分离材料实现对锶的高效萃取至关重要。合成了1,2交替构象的硫代杯[4]冠-4(TCACE),利用FT-IR、1H NMR和Ms对目标产物进行了表征。研究不同稀释剂对萃取的影响,优化得出CH2Cl2为稀释剂,在硝酸... 详细信息

乏燃料后处理的高放废液分离过程中,发展新型分离材料实现对锶的高效萃取至关重要。合成了1,2交替构象的硫代杯[4]冠-4(TCACE),利用FT-IR、1H NMR和Ms对目标产物进行了表征。研究不同稀释剂对萃取的影响,优化得出CH2Cl2为稀释剂,在硝酸浓度为3 mol·L-1,有机相中硫代杯[4]冠-4浓度为1×10-3 mol·L-1,水相中sr2+浓度为5×10-4 mol·L-1,萃取温度为25℃,萃取80 min条件下,平均传质系数为1.36×10-5 m·s-1,sr2+的分配比为0.69。分析了不同条件对硫代杯[4]冠-4对sr2+的萃取影响,研究了萃取计量方程式,实验结果表明萃合物为{sr(NO3)2}·{TCACE}。研究了TCACE对其他金属离子Mo6+、Ni2+、Ag+、sn4+等的萃取效果,表明对sr2+具有较好的选择性。

关键词：硫代杯冠-4 合成 sr^2+ 萃取分离

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