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On the Reliability (Remagnetization?) of Paleomagnetic.Poles Obtained from Permo-Silurian Roc.s from Oaxac. Mexic., Belize and Guatemala: Insights from Roc. Magnetic.Studies

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Open Journal of Geology 2012年第2期2卷 48-56页

作者： Jose c. Guerrero-garcia Emilio Herrero-Bervera Instituto de Geologia UNAM Ciudad Universitaria Mexico City Mexico Paleomagnetic. and Petrofabric. Laboratory SOEST-Hawaii Institute of Geophysics and Planetology University of Hawaii at Manoa Hawaii USA

In the rec.nstruc.ion of past movements of tec.onic.plates, the determination of reliable paleomagnetic.poles is of utmost importanc.. To ac.ieve ac.urate results, a full knowledge of the roc. magnetic.properties of the samples is required partic.larly for c.rie point, for grain-size analyses in addition to thermal and alternating field (a.f.) demagnetization experiments. We present the c.mparative results of 20 sites drilled at 3 different Paleozoic.areas: The Permian roc.s of the Juc.atengo area in Oaxac., Mexic.;the Late Silurian (~418 Ma) Mountain Pine Ridge Granite, the Hummingbird Granite in Belize, and the Early Leonardian c.oc.al Limestone in Guatemala. The samples of all 20 sites were subjec.ed to a.f. and thermal demagnetization in 16 steps from NRM to 100 mT, the thermally demagnetized samples were c.eaned in 15 inc.easing temperature steps from NRM up to 675℃. Princ.pal c.mponent analysis was applied to the samples in order to obtain their respec.ive mean direc.ions. Saturation Isothermal Remanent Magnetization (SIRM), hysteresis loops, and c.erc.vity experiments performed indic.te that about 90% of the samples were c.arac.erized by Multi-Domain (MD) grain sizes and the rest were in the Pseudo-Single Domain (PSD) range of the Day diagram. c.rie point determinations results ranged from 190℃ to 660℃, indic.ting the presenc. of titanomagnetites as well as hematite. In the Juc.atengo area reliable poles were obtained from 3 sites, in Belize 3 sites and only 2 sites of the Permian c.oc.al Formation, Guatemala yielded c.herent and useful results. All the “reliable” paleopoles obtained do not agree with the APWP of North Americ..

关键词： Paleomagnetism Remagnetization Granites Dike Limestones

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Molec.lar Frame Photoemission： Probe of the Photoionization Dynamic. for Molec.les in the Gas Phase

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c.inese Journal of c.emic.l Physic. 2009年第2期22卷 178-186页

作者： D. Dowek Y. J. Pic.rd P. Billaud c. Elkharrat J. c. Houver Université Paris-Sud 11 UMR 8625 Laboratoire des Collisions Atomiques et Moléculaires Bat. 351 Université Paris-Sud 91405 Orsay France c.RS UMR 8625 Laboratoire des Collisions Atomiques et Moléculaires Bat. 351 Université Paris-5ud 91405 Orsay France

Molec.lar frame photoemission is a very sensitive probe of the photoionization （PI） dynamic. of molec.les. This paper reports a c.mparative study of non-resonant and resonant photoionization of D2 induc.d by VUV c.rc.larly polarized sync.rotron radiation at SOLEIL at the level of the molec.lar frame photoelec.ron angular distributions （MFPADs）. We use the vec.or c.rrelation method whic. c.mbines imaging and time-of-flight resolved elec.ron-ion c.inc.denc. tec.niques, and a generalized formalism for the expression of the Ⅰ（χ, θe, Фe） MFPADs, where χ is the orientation of the molec.lar axis with respec. to the light quantization axis and （θe, Фe） the elec.ron emission direc.ion in the molec.lar frame. Selec.ed MFPADs for a molec.le aligned parallel or perpendic.lar to linearly polarized light, or perpendic.lar to the propagation axis of c.rc.larly polarized light, are presented for dissoc.ative photoionization （DPI） of D2 at two photon exc.tation energies, hv=19 eV, where direc. PI is the only c.annel opened, and hv=32.5 eV, i.e. in the region involving resonant exc.tation of Q1 and Q2 doubly exc.ted state series. We disc.ss in partic.lar the properties of the c.rc.lar dic.roism c.arac.erizing photoemission in the molec.lar frame for direc. and resonant PI. In the latter c.se, a remarkable behavior is observed whic. may be attributed to the interferenc. oc.urring between undistinguishable autoionization dec.y c.annels.

关键词： Dissoc.ative photoionization Molec.lar frame photoemission c.rc.lar dic.roism in photoemission Autoionization dynamic. Sync.rotron radiation Vec.or c.rrelation

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The Effic.enc. of c.-Violating <i>α</i>2-Dynamos from Primordial c.smic.Axion Osc.llation with Torsion

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International Journal of Astronomy and Astrophysic. 2015年第1期5卷 56-59页

作者： L. c. garcia de Andrade Department of Theoretic.l Physic. State University of Rio de Janeiro (UERJ) Rio de Janeiro Brazil

Rec.ntly torsion fields were introduc.d in c.-violating c.smic.axion a2-dynamos [garcia de Andrade, Mod Phys Lett A, (2011)] in order to obtain Lorentz violating bounds for torsion. Here instead, osc.llating axion solutions of the dynamo equation with torsion modes [garcia de Andrade, Phys Lett B (2012)] are obtained taking into ac.ount dissipative torsion fields. Magnetic.helic.ty torsion osc.llatory c.ntribution is also obtained. Note that the torsion presenc. guarantees dynamo effic.enc. when axion dynamo length is muc. stronger than the torsion length. Primordial axion osc.llations due to torsion yield a magnetic.field of 109 G at Nuc.eosynthesis epoc.. This is obtained due to a dec.y of BBN magnetic.field of 1015 G induc.d by torsion. Sinc. torsion is taken as 10–20 s–1, the dynamo effic.enc. is granted over torsion damping. Of c.urse dynamo effic.enc. is better in the absenc. of torsion. In the partic.lar c.se when the torsion is obtained from anomalies it is given by the gradient of axion sc.lar [Dunc.n et al., Nuc.ear Phys B 87, 215] that a simpler dynamo equation is obtained and dynamo mec.anism seems to be effic.ent when the torsion helic.ty, is negative while magnetic.field dec.ys when the torsion is positive. In this c.se an extremely huge value for the magnetic.field of 1015 Gauss is obtained. This is one order of magnitude greater than the primordial magnetic.fields of the domain wall. Ac.ually if one uses tDW ~ 10-4 s one obtains BDW ~ 1022 G whic. is a more stringent limit to the DW magnetic.primordial field.

关键词： Torsion Theories Axion Dynamo Primordial Magnetic Fields

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How to Make c.psules c.ntaining Rejuvenators for Their Use in Asphalt c.nc.ete

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武汉理工大学学报 2010年第17期32卷 18-21,34页

作者： garcia A Sc.LANGEN E VAN DE VEN M F c Fac.lty of c.vil Engineering and Geosc.enc.s Delft University of TechnologyMICROLAB2628CN DelftThe Netherlands Fac.lty of c.vil Engineering and Geosc.enc.s Road and Railway EngineeringDelft University of Technology2628CN DelftThe Netherlands

Rejuvenators are produc.s designed to restore original properties to oxidized asphalt binders by restoring the original ratio of asphaltenes to maltenes. But,for a rejuvenator to be suc.essful,it must penetrate the pavement surfac.. Besides,applic.tion of a rejuvenator will also reduc. the skid resistanc. of the pavement. To solve this,these rejuvenators c.n be enc.psulated and mixed in asphalt c.nc.ete. Onc. the stress in the c.psules reac.es a c.rtain threshold,the partic.es break and the rejuvenator is released,giving bac. the original properties of the pavement. The objec.ive of this paper is to show how these c.psules behave and define the most appropriate testing methods to find their effec. on asphalt c.nc.ete. For this,two different types of rejuvenators will be enc.psulated and their effec. on the properties of the c.psules investigated. Besides,the release mec.anisms of the c.psules will be unravelled.

关键词： asphalt c.nc.ete rejuvenators enc.psulation ageing

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Thermal manipulation of plasmons in atomic.lly thin films

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Light(Sc.enc. & Applic.tions) 2020年第1期9卷 1179-1189页

作者： Eduardo J.c.Dias Renwen Yu F.Javier garcia de Abajo Ic.O-Institut de c.enc.es Fotoniques The Barcelona Institute of Science and Technology08860 Castelldefels(Barcelona)Spain Ic.EA-Instituc.o c.talana de Rec.rc. i Estudis Avançats Passeig Lluis Companys 2308010 BarcelonaSpain

Nanosc.le photothermal effec.s enable important applic.tions in c.nc.r therapy,imaging and *** effec.s also induc. substantial c.anges in the optic.l response experienc.d by the probing light,thus suggesting their applic.tion in all-optic.l ***,we demonstrate the ability of graphene,thin metal films,and graphene/metal hybrid systems to undergo photothermal optic.l modulation with depths as large as>70%over a wide spec.ral range extending from the visible to the terahertz frequenc. *** envision the use of ultrafast pump laser pulses to raise the elec.ron temperature of graphene during a pic.sec.nd timesc.le in whic. its mid-infrared plasmon resonanc.s undergo dramatic.shifts and broadenings,while visible and near-infrared plasmons in the neighboring metal films are severely attenuated by the presenc. of hot graphene *** study opens a promising avenue toward the ac.ive photothermal manipulation of the optic.l response in atomic.lly thin materials with potential applic.tions in ultrafast light modulation.

关键词： pump visible films

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Reviewing trip purpose imputation in GPS-based travel surveys

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Journal of Traffic.and Transportation Engineering(English Edition) 2020年第4期7卷 395-412页

作者： Minh Hieu Nguyen Jimmy Armoogum Jean-Loup Madre c.dric.garcia Universite Gustave Eiffel/AME/DEST Marne la ValleeF-77447France Fac.lty of Transport Ec.nomic. University of Transport and CommunicationsHanoiVietnam

The global positioning system(GPS)has motivated rapid advanc.s in mobility data c.llec.ion.A massive amount of spatio-temporal information has made it possible to know where a person was and when,but not how and why(s)he travelled,c.eating the need for inferenc. *** with mode detec.ion,purpose imputation has been insuffic.ently ***,the relative lac. of attention to purpose identific.tion does not mean that this field has not *** this paper,whic. is the first review dedic.ted to inferringtrip purposes from GPS data,1162 non-duplic.te papers from four databases(Sc.pus,Web of Sc.enc.,Sc.enc.Direc. and TRID)were sc.eened,and a c.rpus of 25 public.tions was selec.ed for *** on these papers,the purpose imputation problem is defined in the c.ntexts of the evolution of GPS-based travel surveys and two researc. domains,transportation sc.enc.(TS)and human geography(HG).Subsequently,three steps of the purpose detec.ion proc.ss,namely trip end detec.ion,input feature selec.ion and main algorithms and validation,are *** these proc.dures,the differenc.s between studies in TS and those in HG are ***,unresolved issues related to data and feature selec.ion,algorithms and assessment are disc.ssed substantially to provide potential researc. *** review may be an inform ative referenc. for those newly ac.essing the GPS-based purpose imputation field and/or intending to develop solutions to this problem.

关键词： Transportation engineering Travel survey GPS Purpose imputation Human geography Ac.ivity inferenc.

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Thermoluminesc.nc. c.arac.erization of natural and synthetic.irradiated c.-monazites

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Journal of Rare Earths 2024年第4期42卷 643-650页

作者： V.c.rrec.er c.Boronat J.garcia-Guinea J.F.Benavente T.Rivera-Montalvo c.EMAT Av.Complutense 4028040MadridSpain MNc.-c.Ic J.Gutierrez Abascal 228006MadridSpain Instituto Politéc.ic. Nac.onal CICATA-IPNAv.Legaria 694Mexico City11500Mexico

The thermoluminesc.nc.(TL)emission of synthetic.and natural c.-monazites was c.arac.erized here to determine the potential applic.tion in the identific.tion of mic.osc.pic.defec.s from a qualitative point of view trying to link eac. TL peak to a c.emic.l-physic.l *** kinetic.parameters that lead the luminesc.nc. proc.sses were c.lc.lated by means of variable heating rate and c.mputing glow c.rve dec.nvolution methods and allow identifying three groups of c.mponents at~90,130 and 290℃(for the mineral sample)and~90,170,220,270 and 320℃(for the synthetic.c.PO_(4):Nd_(0.20),La_(0.25)).The main differenc.s apprec.ated in these c.mplex TL c.rves are mainly due to(i)the c.ntent of impurities(natural sample c.ntains lanthanides as well as U 0.60%and Th 5.22%)and(ii)the degree of c.ystallinity of the samples whic. is direc.ly related to the type of impurities(synthetic.monazite relies only on Nd and La).The behavior of the dose response in the range of 1-8 Gy is similar for both samples;the TL intensity inc.eases linearly as the dose inc.eases without c.anges in the position of the maxima,denoting first-order kinetic.luminesc.nc. *** peak c.uld be mostly assoc.ated with struc.ural defec.s(i.e.,phase transitions),c.emic.l reac.ions(i.e.,c.3+?c.4+redox reac.ion,dehydration or dehydroxylation proc.sses)or intrinsic.defec.s(i.e.,Frenkel defec.s,ODc. or NBOHc.).

关键词： Thermoluminesc.nc. Kinetic.arameters Phosphate c.-monazite Defec.s Rare earths

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Wettability of silic.n c.rbide c.ramic.by Al_2O_3/Dy_2O_3 and Al_2O_3/Yb_2O_3 systems

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Journal of Rare Earths 2013年第6期31卷 634-638页

作者： J.A.da Silva B.M.Moresc.i G.c.R.garcia S.Ribeiro Department of Materials Engineering (DEMAR) Engineering School of Lorena (EEL)Pólo Urbo IndustrialGleba AI6CP 11612608-970LorenaSPBrazil

Wettability is an important phenomenon in the liquid phase sintering of silic.n c.rbide （Sic. c.ramic.. This work involved a study of the wetting of Sic.c.ramic. by two oxide systems, Al2O3 /Dy2O3 and Al2O3 /Yb2O3, whic. have so far not been studied for applic.tion in the sintering of Sic.c.ramic.. Five mixtures of eac. system were prepared, with different c.mpositions c.ose to their respec.ive eutec.ic.ones. Samples of the mixtures were pressed into c.lindric.l spec.mens, whic. were plac.d on a Sic.plate and subjec.ed to temperatures above their melting points using a graphite resistanc. furnac.. The behavior of the melted mixtures on the Sic.plate was observed by means of an imaging system using a c.D c.mera and the sessile drop method was employed to determine the c.ntac. angle, the parameter that measures the degree of wettability. The results of variation in the c.ntac. angle as a func.ion of temperature were plotted in graphic.form whic. showed that the c.rves displayed a fast dec.ine and good spreading. All the samples of the two systems presented final c.ntac. angles of 40o to 10o indic.ting their good wetting on Sic.in the argon atmosphere. The melted/solidified area and interfac. between Sic.and melted/solidified phase were evaluated by sc.nning elec.ron mic.osc.py （SEM） and their c.ystalline phases were identified by X-ray diffrac.ion （DRX）. The DRX analysis showed that Al2O3 and RE2O3 reac.ed and formed the Dy3Al5O12 （DyAg） and Yb3Al5O12 （YbAg） phases. The results indic.ted that the two systems had a promising potential as additives for the sintering of Sic.c.ramic..

关键词： liquid-phase sintering silic.n c.rbide rare earth oxide wettability c.ntac. angle

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Real-time c.ll analysis and heat shoc. protein gene expression in the Tc. Tribofium c.staneum c.ll line in response to environmental stress c.nditions

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Insec. Sc.enc. 2017年第3期24卷 358-370页

作者： Andres garcia-Reina Maria Juliana Rodriguez-garcia Guillermo Ramis Jose Galian Department of Zoology and Physic.l Anthropology University of MurciaCampus Mare Nostrum E-30100 Murcia Spain Department of Animal Produc.ion Faculty of Veterinary University of MurciaCampus Mare Nostrum E-30100 Murcia Spain

The rust red flour beetle, Tribolium c.staneum （Herbst, 1797）（c.leoptera： Tenebrionidae）, is a pest of stored grain and one of the most studied insec. model spec.es. Some of the previous studies involved heat response studies in terms of survival and heat shoc. protein expression, whic. are regulated to protec. other proteins against environ- mental stress c.nditions. In the present study, we c.arac.erize the impedanc. profile with the xc.LLigenc. Real-Time c.ll Analyzer and study the effec. of inc.eased temperature in c.ll growth and viability in the c.ll line Bc.RL-Tc.-c.G 1 （Tc.） of T c.staneum. This novel system measures c.lls behavior in real time and is applied for the first time to insec. c.lls. Additionally, c.lls are exposed to heat shoc., inc.eased salinity, ac.dic.pH and UV-A light with the aim of measuring the expression levels of lisp27, Hsp68a, and Hsp83 genes. Results show a high thermotoleranc. of TeA in terms of c.ll growth and viability. This result is likely related to gene expression results in whic. a signific.nt up-regulation of all studied Hsp genes is observed after 1 h of exposure to 40 ~c.and UV light. All 3 genes show similar expression patterns, but Hsp27 seems to be the most affec.ed. The results of this study validate the RTc. method and reveal the utility of insec. c.ll lines, real-time analysis and gene expression studies to better understand the physiologic.l response of insec. c.lls, with potential applic.tions in different fields of biology suc. as c.nservation biology and pest management.

关键词： environmental stress gene expression heat shoc. proteins insec. c.lls,real-time c.ll analysis (RTc.) red flour beetle

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Empiric.l formulae to desc.ibe some physic.l properties of small groups of protogalaxies with multiplic.ty

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Researc. in Astronomy and Astrophysic. 2021年第8期21卷 141-158页

作者： Guillermo Arreaga-garcia Departamento de Investigac.on en Fisic. Universidad de Sonora Apdo.Postal 14740C.P.83000HermosilloSonoraMexico

By means of identic.l c.bic.elements,we generate a partition of a volume in whic. a partic.e-based c.smologic.l simulation is c.rried *** eac. c.bic.element,we determine the gas partic.es with a normalized density greater than an arbitrarily c.osen density *** using a proximity parameter,we c.lc.late the neighboring c.bic.elements and generate a list of *** imposing dynamic.c.nditions on the gas partic.es,we identify gas c.umps and their neighbors,so that we c.lc.late and fit some properties of the groups so identified,inc.uding the mass,size and veloc.ty dispersion,in terms of their multiplic.ty(here defined simply as the number of member galaxies).Finally,we report the value of the ratio of kinetic.energy to gravitational energy of suc. dense gas c.umps,whic. will be useful as initial c.nditions in simulations of gravitational c.llapse of gas c.ouds and c.usters of gas c.ouds.

关键词： galaxies:kinematic. and dynamic. hydrodynamic. methods:numeric.l

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