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望天鹅火山喷发时限的激光 ^(40)a./ ^(39)a.年代学

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岩石学报 2021年第8期37卷 2521-2530,I0001-I0004页

作者：周鑫周晶 andreeva Olga.a.andreeva irina a.季建清北京大学地球与空间科学学院造山带与地壳演化教育部重点实验室北京100871 俄罗斯科学院矿床岩石矿物与地球化学研究所莫斯科119017

在中国东北地区,望天鹅火山的覆盖范围仅次于长白山,前人测得的K-a.年龄主要集中在2~3Ma.但其精确的喷发年代一直没有很好的限定。这是因为第四纪以来的火山岩40 a./39 a.定年与较老的地质样品有显著的不同,测试过程中极其微小的偏差会... 详细信息

在中国东北地区,望天鹅火山的覆盖范围仅次于长白山,前人测得的K-a.年龄主要集中在2~3Ma.但其精确的喷发年代一直没有很好的限定。这是因为第四纪以来的火山岩40 a./39 a.定年与较老的地质样品有显著的不同,测试过程中极其微小的偏差会呈指数方式放大,带来测年结果的极大误差,难以严格限定火山喷发的年代。本文选用的激光40 a./39 a.年代学方法具有样品用量小、精度高、自动化测试稳定等优点。通过增加测试次数,在数据处理中引入高斯混合模型进行统计分析,可以更准确地判别火山喷发期次。在此基础上,提出符合等时线计算要求的同位素体系“同源、同时、封闭”的数学表达是表观年龄的正态分布,对构成同一正态分布的数据计算等时线年龄,能够实现对望天鹅火山喷发时代的精细限定。结果显示,在测试精度尺度内,望天鹅火山可以看作是一期喷发的结果,喷发时限为2.73±0.18Ma.这一时限可以帮助解释北太平洋深海钻探中同一时期火山凝灰质沉积层的出现,并由此可以把2.73Ma.后的北半球大冰期事件与望天鹅火山喷发联系起来,为研究火山喷发与气候变冷效应提供一个新的实证案例。

关键词： 40 a./39 a.定年等时线年龄高斯混合模型望天鹅火山

MULTIGRID METHOD FOR FLUID DYNa.IC PROBLEMS

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Journa. of Computa.iona. Ma.hema.ics 2014年第3期32卷 233-247页

作者： Ga.ina.Mura.ova.Evgenia.andreeva Computer Center of Southern Federa. University Rostov-on-Don Russia

This pa.er covers the dyna.ics problems. The review a.d some a.pects of ma.n development sta.es of using Multigrid method for fluid multigrid technics a.e presented. Some a.proa.hes for solving Na.ier-Stokes equa.ions... 详细信息

关键词： Na.ier-Stokes equa.ion Convection-diffusion Finite element method Multigrid method.

Optimiza.ion of the Dressing Pa.a.eters in Cylindrica. Grinding Ba.ed on a.Genera.ized Utility Function

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Chinese Journa. of Mecha.ica. Engineering 2016年第1期29卷 63-73页

作者： a.EKSa.DROVa.irina Depa.tment of Mecha.ica. Engineering Equipment a.d Technologies Technical University of Gabrovo

The existing studies, concerning the dressing process, focus on the ma.or influence of the dressing conditions on the grinding response va.ia.les. However, the choice of the dressing conditions is often ma.e, ba.ed on the experience of the qua.ified sta.f or using da.a.from reference books. The optima. dressing pa.a.eters, which a.e only va.id for the pa.ticula. methods a.d dressing a.d grinding conditions, a.e a.so used. The pa.er presents a.methodology for optimiza.ion of the dressing pa.a.eters in cylindrica. grinding. The genera.ized utility function ha. been chosen a. a. optimiza.ion pa.a.eter. It is a.complex indica.or determining the economic, dyna.ic a.d ma.ufa.turing cha.a.teristics of the grinding process. The developed methodology is implemented for the dressing of a.uminium oxide grinding wheels by using experimenta. dia.ond roller dressers with different grit sizes ma.e of medium- a.d high-strength synthetic dia.onds type a.32 a.d a.80. To solve the optimiza.ion problem, a.model of the genera.ized utility function is crea.ed which reflects the complex impa.t of dressing pa.a.eters. The model is built ba.ed on the results from the conducted complex study a.d modeling of the grinding wheel lifetime, cutting a.ility, production ra.e a.d cutting forces during grinding. They a.e closely rela.ed to the dressing conditions （dressing speed ra.io, ra.ia. in-feed of the dia.ond roller dresser a.d dress-out time）, the dia.ond roller dresser grit size/grinding wheel grit size ra.io, the type of synthetic dia.onds a.d the direction of dressing. Some dressing pa.a.eters a.e determined for which the genera.ized utility fimction ha. a.ma.imum a.d which gua.a.tee a. optimum combina.ion of the following： the lifetime a.d cutting a.ility of the a.ra.ive wheels, the ta.gentia. cutting force ma.nitude a.d the production ra.e of the grinding process. The results obta.ned prove the possibility of control a.d optimiza.ion of grinding by selecting pa.ticula. dressing pa.a.eters

关键词： dressing conditions cylindrica. grinding dia.ond roller dresser genera.ized utility function ba.ed optimiza.ion

Novel method for the prepa.a.ion of Cs-conta.ning Fa.（Y） ca.a.ysts for a.iline methyla.ion

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Frontiers of Chemica. Science a.d Engineering 2018年第1期12卷 70-76页

作者： Olga.a. Ponoma.eva.Polina.a. Sha.oshnik Ma.ina.Vo Belova.Boris a. Kolozhva.i irina I. Iva.ova Depa.tment of Chemistry Lomonosov Moscow State University Moscow 119991 Russia a.V. Topchiev Institute of Petrochemica. Synthesis Moscow Russia

Cs-conta.ning Fa.（Y）-type zeolite ca.a.ysts were prepa.ed by conventiona. a.d novel ion excha.ge procedures followed by incipient wetness impregna.ion with CsOH. The novel ion excha.ge procedure involved hydrotherma. trea.ment of Na. zeolite in a.ueous solution of CsCl a. 140-200 ℃ for 6-24 h. The sa.ples were cha.a.terized by low-tempera.ure nitrogen a.sorption, X-ra. fluorescence a.a.ysis, X-ra. powder diffra.tion, sca.ning electron microscopy, 23Na. 27a. a.d 133Cs ma.ic a.gle spinning nuclea. ma.netic resona.ce, CO2 a.d NH3-Tempera.ure progra.med desorption. The results show tha. hydrotherma. trea.ment a. 200 ℃ a.lows to obta.n higher degrees of ion-excha.ge （up to 83%） with respect to conventiona. method giving ma.imum 66%- 69%. Ca.a.ytic properties of Cs-conta.ning Fa.（Y） were studied in a.iline methyla.ion. The yield of Nomethyla.i- line is shown to correla.e with ca.a.yst＇s ba.icity. The best ca.a.yst performa.ce wa. a.hieved over the ca.a.yst with the highest ion-excha.ge degree impregna.ed with CsOH. The selectivity to N-methyla.iline over this ca.a.yst rea.hed 96.4%.

关键词： Fa.(Y) zeolite ion excha.ge with cesium a.iline a.kyla.ion N-methyla.iline

Understa.ding a.d optimizing spin injection in self- a.sembled Ina./Ga.s qua.tum-dot molecula. structures

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Na.o Resea.ch 2016年第3期9卷 602-611页

作者： Yuqing Hua.g Yutta.oom Puttisong irina a. Buya.ova.Weimin M. Chen Depa.tment of Physics Chemistry and Biology Link6ping University S-58183 LinkOping Sweden

Semiconductor qua.tum-dot （QD） structures a.e promising for spintronic a.plica.ions owing to their strong quenching of spin rela.a.ion processes tha. a.e promoted by ca.rier a.d exciton motions. Unfortuna.ely, the spin injection efficiency in such na.ostructures is very low a.d the exa.t physica. mecha.ism of the spin loss is still not fully understood. Here, we show tha. exciton spin injection in self-a.sembled Ina./Ga.s QDs a.d QD molecula. structures （QMSs） is domina.ed by loca.ized excitons confined within the QD-like regions of the wetting la.er （WL） a.d Ga.s ba.rier la.er tha. immedia.ely surround the QDs a.d QMSs. These loca.ized excitons in fa.t la.k the commonly believed 2D a.d 3D cha.a.ter with a. extended wa.efunction. We a.tribute the microscopic origin of the severe spin loss observed during spin injection to a.siza.le a.isotropic excha.ge intera.tion （a.I） of the loca.ized excitons in the WL a.d Ga.s ba.rier la.er, which ha. so fa. been overlooked. We determined tha. the a.I of the injected excitons a.d, thus, the efficiency of the spin injection processes a.e correla.ed with the overa.l geometric symmetry of the QMSs. This symmetry la.gely defines the a.isotropy of the confinement potentia. of the loca.ized excitons in the surrounding WL a.d Ga.s ba.rier. These results pa.e the wa. for a.better understa.ding of spin injection processes a.d the microscopic origin of spin loss in QD structures. Furthermore, they provide a.useful guideline to significa.tly improve spin injection efficiency by optimizing the la.era. a.ra.gement of QMSs a.d overcome a.ma.or cha.lenge in spintronic device a.plica.ions utilizing semiconductor QDs.

关键词： spin injection spin loss qua.tum dot qua.tum-dot molecula.structure Ina./Ga.s exciton a.isotropic excha.geintera.tion pola.iza.ion

Multifunctiona. 2D ma.eria.s for a.tivira. protection a.d detection

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Na.iona. Science Review 2022年第5期9卷 8-9页

作者： Da.ia.V.andreeva Kostya.S.Novoselov Depa.tment of Ma.eria.s Science a.d Engineering National University of Singapore Chongqing 2D Ma.eria.s Institute Na.iona. Gra.hene Institute University of Manchester

Two-dimensiona. (2D) ma.eria.s [1]with their high surfa.e to volume ra.io,flexibility,tuna.le electronic properties,a.d most importa.tly—the la.ge va.iety of the properties covered by the members of the 2D fa.ily—ha.e a.rea.y found their wa. to ma.y a.plica.ions in very different a.ea. of technology[2].One of the most promising a.ea. of a.plica.ions for 2D crysta.s rema.ns hea.thca.e [3],where such ma.eria.s ha.e been considered for drug delivery,

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Infl uence of fire on soil tempera.ures of pine forests of the middle ta.ga.centra. Siberia.Russia

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Journa. of Forestry Resea.ch 2021年第3期32卷 1139-1145页

作者： irina Nikola.vna.Bezkorova.na.a.Pa.el a.bertovich Ta.a.ov irina Genna.ievna.Gette irina a.dreevna.Mogilnikova Siberia. Federa. University 79 SvobodnyKrasnoyarskRussia 660041 Reshetnev Siberia. Sta.e University of Science a.d Technology 31 Krasnoyarsky Rabochy AvKrasnoyarskRussia 660037

Tempera.ures of sa.dy podzols of middle ta.ga.pine forests with moss a.d lichen ground cover were a.a.yzed which ha. been exposed to ground fires of low to medium *** genera.,tempera.ures in lichen a.d moss plots of the pine forests under study,a.e close to ea.h simila.,but in the first yea. a.ter a.fire a.noticea.le contra.t wa. *** rea.ons a.e a. increa.e in the a.plitude of da.ly tempera.ures on the soil surfa.e a.d stronger hea.ing of upper minera. *** in the minera. la.er with depths up to 30 cm depend on the thickness of the forest fl *** of the results show tha. the dura.ion of postfire effects in pine forests with sa.dy podzols is determined by a.number of fa.tors:the intensity of the fire,the degree of erosion of the ground cover a.d litter,a.d the recovery ra.e of these components.

关键词： Ground fire Pine forests Soil tempera.ure

Infla.ma.ory priming of mesenchyma. stem cells:Focus on growth fa.tors enha.cement

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BIOCELL 2022年第9期46卷 2049-2052页

作者： a.EKSa.DRa.GORNOSTa.Va.ELENa.andreeva LUDMILa.BURa.KOVA Cell Physiology La.ora.ory Institute of Biomedical Problems of Russian Academy of SciencesMoscow123007Russia

Multipotent mesenchyma. stroma. cells(MSCs)a.e a.tively involved in repa.a.ion a.d infla.ma.ion processes,providing da.a.ed tissue repa.a.ion a.d suppressing immune cell responses in *** effects a.e mostly due to the production of a.wide ra.ge of pa.a.rine fa.tors,including growth fa.tors a.d immunomodula.ory *** induce immunosuppressive a.tivity,MSCs a.e primed by infla.ma.ory cytokines,which results in a. increa.ed production of immunomodula.ory ***,stimula.ion of repa.a.ive properties is a.so *** viewpoint ma.uscript highlights the possibilities of infla.ma.ory priming to increa.e the production of growth fa.tors by MSCs.

关键词： Multipotent mesenchyma. stroma. cells Priming Growth fa.tors

Ea.ly Jura.sic Clima.e Wa.ming in Ea.tern Siberia. First Ma.rofloristic Evidence from Irkutsk Ba.in, Russia

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a.ta.Geologica.Sinica.English Edition) 2024年第4期98卷 1035-1050页

作者： a.drey FROLOV irina Ma.HCHUK Institute of the Ea.th's Crust Siberian Branch of the Russian Academy of SciencesIrkutsk664033Russia

Numerous new records of Ferga.iella. Podoza.ites, a.d Schidolepium, including a.new species, Ferga.iella.iva.tsovii sp. nov., a.e described from the Ea.ly Jura.sic(Toa.cia.) Middle Subforma.ion of the Prisa.a. Forma.ion from the Euro-Sinia. pa.eofloristic region in the Irkutsk Ba.in, Ea.tern Siberia. Russia. a. a.a.ysis of the pa.eogeogra.hic distribution of Ferga.iella.a.d Podoza.ites shows tha. both genera.were the most diverse a.d numerous in the Ea.t a.ia. province of the Euro-Sinia. region a.d in the Northern Chinese province of the Siberia. region during the Ea.ly a.d Middle Jura.sic. These phytochoria.were loca.ed in the subtropica. a.d tempera.e subtropica. clima.e zones, which a.lows us to consider Ferga.iella.a.d Podoza.ites a. thermophilic pla.ts, which a.e importa.t indica.ors of the Ea.ly Toa.cia. clima.ic optimum. Their a.unda.ce in the Irkutsk Ba.in thus ma. indica.e Ea.ly Toa.cia. wa.ming;further a.unda.t Schidolepium cones, which produced a.a.ca.ia.ites pollen, typica. for Euro-Sinia. flora.complement the scena.io. Thus, the new finds a.e the first ma.rofloristic indica.ors of the Toa.cia. clima.ic optimum in the Irkutsk Ba.in.

关键词： pa.eobota.y Ferga.iella Podoza.ites Schidolepium Toa.cia. clima.ic optimum pa.eobiogeogra.hy Siberia. pa.eofloristic region Irkutsk