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A new cache of Eoarchaean detrital zircons from the singhbhum craton,eastern India and constraints on early Earth geodynamics

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Geoscience Frontiers 2019年第4期10卷 1359-1370页

作者： Bulusu sreenivas sukanta dey Y.J. Bhaskar Rao T. Vijaya Kumar E.V.s.s.K. Babu Ian s. Williams CsIR-National Geophysical Research Institute Hyderabad 500007India department of Earth sciences Indian Institute of Science Education and ResearchKolkata 741246India Research school of Earth sciences The Australian National UniversityCanberra 2601Australia

The dominant geodynamic processes that underpin the formation and evolution of Earth’s early crust remain enigmatic calling for new information from less studied ancient cratonic ***,we present U-Pb ages and Hf isotopic compositions of detrital zircon grains from^2.9 Ga old quartzites and magmatic zircon from a 3.505 Ga old dacite from the Iron Ore Group of the singhbhum craton,eastern *** detrital zircon grains range in age between 3.95 Ga and 2.91 *** with the recently reported Hadean,Eoarchean xenocrystic(up to 4.24 Ga)and modem detritus zircon grains from the singhbhum craton,our results suggest that the Eoarchean detrital zircons represent crust generated by recycling of Hadean felsic crust formed at^4.3-4.2 Ga and^3.95 *** observe a prominent shift in Hf isotope compositions at^3.6-3.5 Ga towards super-chondritic values,which signify an increased role for depleted mantle and the relevance of plate *** Paleo-,Mesoarchean zircon Hf isotopic record in the craton indicates crust generation involving the role of both depleted and enriched mantle *** infer a short-lived suprasubduction setting around^3.6-3.5 Ga followed by mantle plume activity during the Paleo-,Mesoarchean crust formation in the singhbhum *** singhbhum craton provides an additional repository for Earth’s oldest materials.

关键词： U-Pb zircon ages Hf isotopes singhbhum craton Hadean Eoarchean Geodynamics

Overcast sky condition prevails on and influences the biometeorology of the tropical Andean Páramos

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Journal of Mountain science 2023年第1期20卷 78-86页

作者： Paola MONTENEGRO-dÍAZ Rolando CELLERIALVEAR Galo CARRILLO-ROJAs departamento de Recursos Hídricos y Ciencias Ambientales Universidad de CuencaCuenca010207Ecuador Facultad de Ingeniería Universidad de CuencaCuenca010207Ecuador Facultad de Ciencias Químicas Universidad de CuencaCuenca010207Ecuador

Clouds play a major role in modulating the biometeorological processes. We studied the influence of cloudiness on four biometeorological variables:daily air temperature(Tair), relative humidity(RH),reference evapotranspiration(ETr),and photosynthetic active radiation(PAR), recorded at four sites of Andean Páramos in southern Ecuador during 2.5 to 5.5 years. First, we quantified both the cloud cover percentage(Cloud%) creating cloud masks over the visible bands of Landsat 7 images and the sky condition(K_(T)) using the records of solar and extraterrestrial radiation. second, we estimated KTfrom Cloud%. Finally, we quantified T_(air), RH, ET_(r), and PAR under clear, cloudy, and overcast K_(T) and their dependence on KT. The average Cloud% ranged between 65%–76%, and KTcorroborated the prevailing overcast sky(between 55% and 72.5% of the days) over the páramos. The proposed model performed well in the sites of calibration(R^(2)= 0.80;MBE = 0.00;RMsE = 0.05) and validation(R^(2)= 0.74;MBE =-0.07;RMsE = 0.11). The overcast sky diminished T_(air)(≤ 10℃), ET_(r)(≤ 1.6 mm day-1), and PAR(4 MJ m^(-2)day^(-1)) and increased RH(≥ 88%),while the variables showed the opposite behavior during the uncommon clear sky(≤ 5.5% of the days).Thus, mostly the dynamic of RH(R^(2)≥ 0.62), ETr(R^(2)≥ 0.85), and PAR(R2≥ 0.77) depended on K_(T). Hence,the prevailing overcast sky influenced the biometeorology of the páramos.

关键词： Cloudiness indicator Clearness index satellite imagery Tropical Andes

A COMPACT UPWINd sECONd ORdER sCHEME FOR THE EIKONAL EQUATION

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Journal of Computational Mathematics 2010年第4期28卷 489-516页

作者： J.-d. Benamou songting Luo Hongkai Zhao INRIA INRIA B.P. 105 78153 Le Chesnay Cedex France department of Mathematics Michigan State University East Lansing MI 48824 USA department of Mathematics University of California Irvine CA 92697 USA

We present a compact upwind second order scheme for computing the viscosity solution of the Eikonal equation. This new scheme is based on： 1. the numerical observation that classical first order monotone upwind schemes for the Eikonal equation yield numerical upwind gradient which is also first order accurate up to singularities; 2. a remark that partial information on the second derivatives of the solution is known and given in the structure of the Eikonal equation and can be used to reduce the size of the stencil. We implement the second order scheme as a correction to the well known sweeping method but it should be applicable to any first order monotone upwind scheme. Care is needed to choose the appropriate stencils to avoid instabilities.

关键词： Eikonal equation Upwind scheme Hamilton-Jacobi Viscosity solution sweeping method.

Region-Aware Trace signal selection Using Machine Learning Technique for silicon Validation and debug

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Computer Modeling in Engineering & sciences 2019年第7期120卷 25-43页

作者： R.Agalya R.Muthaiah d.Muralidharan Junior Research Fellow School of ComputingSASTRA Deemed UniversityThirumalaisamudramThanjavur-613401TamilnaduIndia Associate dean School of ComputingSASTRA Deemed UniversityThirumalaisamudramThanjavur-613401TamilnaduIndia Assistant Professor School of ComputingSASTRA Deemed UniversityThirumalaisamudramThanjavur-613401TamilnaduIndia

In today’s modern design technology,post-silicon validation is an expensive and composite *** major challenge involved in this method is that it has limited observability and controllability of internal *** will be an issue during execution how to address the useful set of signals and store it in the on-chip trace *** existing approaches are restricted to particular debug set-up where all the components have equivalent prominence at all the ***,the verification engineers will emphasis only on useful functional regions or *** to some constraints like clock gating,some of the regions can be ignored during ***,some of these regions can be verified deeply and have minimum errors compared to other control *** proposed system focusses on random signals that identify more errors which are prone to signal selection technique with low area *** enhance the observability,a machine learning technique is *** on the training samples of smaller designs,a model is developed to find out the contiguous neighbours of each *** can eliminate the obstacles of unknown *** system demonstrates using Opencores and IsCAs’89 benchmark circuits that result in easy and fast error detection compared to the state-of-theart of other *** is also verified using gate-level error models by cross-validation of each debug run.

关键词： Controllability error propagation machine learning observability signal selection

Microstructural evaluation and nanohardness of an AlCoCuCrFeNiTi high-entropy alloy

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International Journal of Minerals,Metallurgy and Materials 2019年第5期26卷 634-641页

作者： C.d.Gómez-Esparza R.Peréz-Bustamante J.M.Alvarado-Orozco J.Mu?oz-salda?a R.Martínez-sánchez J.M.Olivares-Ramírez A.duarte-Moller Centro de Investigación en Materiales Avanzados (CIMAV) Laboratorio Nacional de Nanotecnología CONACYT-Corporación Mexicana de Investigación en Materiales s.A.de C.V.(COMIMsA) Centro de Ingeniería y desarrollo Industrial Querétaro Campus Centro de Investigación y de Estudios Avanzados del IPN Unidad Querétaro Universidad Tecnológica de san Juan del Río Escuela de Ingeniería Civil Industrialy Mecánica Universidad De La Salle Bajío

An AlCoCuCrFeNiTi high-entropy alloy(HEA) was prepared by mechanical alloying and sintering to study the effect of Ti addition to the widely studied AlCoCuCrFeNi system. The structural and microstructural characteristics were investigated by X-ray diffraction(XRd), scanning electron microscopy(sEM), and transmission electron microscopy(TEM). The formation of four micrometric phases was detected: a Cu-rich phase with a face-centered cubic(fcc) structure, a body-centered cubic(bcc) solid solution with Cu-rich plate-like precipitates(fcc), an ordered bcc phase, and a tetragonal structure. The XRd patterns corroborate the presence of a mixture of bcc-, fcc-, and tetragonal-structured phases. The Vickers hardness of the alloy under study was more than twice that of the AlCoCuCrFeNi alloy. Nanoindentation tests were performed to evaluate the mechanical response of the individual phases to elucidate the relationship between chemical composition, crystal structure, and mechanical performance of the multiphase microstructure of the AlCoCuCrFeNiTi HEA.

关键词： high-entropy alloys mechanical alloying microstructure nanoindentation

Optimal thermoelectric figure of merit of si/Ge core-shell nanowires

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Nano Research 2015年第8期8卷 2611-2619页

作者： Kaike Yang Andres Cantarero Angel Rubio Roberto d'Agosta Nano-Bio spectroscopy Group and ETsF scientific development Center Departamento de Fisica de Materiales Universidad del Pais Vasco UPV/EHU San Sebastian 20018 Spain Instituto de Ciencia de Materiales Universidad de Valencia Valencia 46071 Spain Ikerbasque Basque foundation for Science Bilbao 48013 Spain

We investigate the thermoelectric energy conversion efficiency of si and Ge nanowires, and in particular, that of si/Ge core-shell nanowires. We show how the presence of a thin Ge shell on a si core nanowire increases the overall figure of merit. We find the optimal thickness of the Ge shell to provide the largest figure of merit for the devices. We also consider Ge core/si shell nanowires, and show that an optimal thickness of the si shell does not exist, since the figure of merit is a monotonically decreasing function of the radius of the nanowire. Finally, we verify the empirical law relating the electron energy gap to the optimal working temperature that maximizes the efficiency of the device.

关键词： thermoelectric properties seebeck coefficient silicon and germanium core-shell nanowires

A simple umbelliferone based fluorescent probe for the detection of nitroreductase

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Frontiers of Chemical science and Engineering 2018年第2期12卷 311-314页

作者： Adam C. sedgwick Alex Hayden Barry Hill steven d. Bull Robert B. P. Elmes Tony d. James department of Chemistry University of Bath Bath BA2 7AY UK department of Chemistry Maynooth University Maynooth Co. Kildare Ireland

A simple nitrobenzyl-umbelliferone （NCOU1） was synthesised containing a nitroreductase （NTR） trigger moiety. The presence of NTR, resulted in the fragmentation of the parent molecule and release of the highly emissive fluorophore umbelliferone via an NTR-catalyzed reduction of the nitro group. In the presence of the NTR enzyme, NCOU1 gave rise to a 5-fold increase in fluorescence intensity at 455 nm and was selective for NTR over other reductive enzymes. These results indicate that NCOU1 can be used as a simple assay for the detection of NTR.

关键词： NITRO RAdICALs NTsR1 gene FLUOREsCENT PROBEs skimmetin Nitroreductases noise-temperature ratio

The correlation between insulin and OCT-6 transcription factor in schwann cells and sciatic nerve of diabetic rats

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Genes & diseases 2018年第2期5卷 130-136页

作者： Mallahalli s.Manu Kuruvanthe s.Rachana Gopal M.Advirao department of Biochemistry Davangere UniversityDavangereKarnatakaIndia

Insulin signal is one of the vital signaling cascade required for schwann cells to myelinate the axons of peripheral nervous system(PNs).Myelin formation of peripheral nerve is a complex molecular event controlled by different neurotrophic and transcription *** altered or failure in this signaling progression is one of the reasons behind the demyelination of peripheral neurons in diabetic peripheral neuropathy(dPN).The schwann cell in PNs includes POU domain transcription factor OCT-6 *** factor is considered as crucial for the initiation and enhancement of myelination during nerve *** know the importance of OCT-6 gene,here we studied the long term expression of OCT-6 nuclear protein in sciatic nerve of normal and diabetic neuropathic *** for the first time we elucidated the role of insulin in controlling the expression of OCT-6 in hyperglycemic schwann cells and sciatic nerve of diabetic neuropathic *** results shows that,there will be long term OCT-6 expression in sciatic nerve of adult rats and also their significant decrease is observed in the diabetic ***,addition of Insulin for primary schwann cells and diabetic rats shows the increased OCT-6 expression in both in vivo and in *** these results indicate the failure of OCT-6 support in neuropathy and also the importance of insulin signaling cascade in the expression of OCT-6 transcription factor.

关键词： diabetic peripheral neuropathy Insulin OCT-6 schwann cells sciatic nerve

solar spectral conversion based on plastic films of lanthanide-doped ionosilicas for photovoltaics:down-shifting layers and luminescent solar concentrators

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Journal of Rare Earths 2020年第5期38卷 531-538页

作者： M.A.Cardoso s.F.H.Correia A.R.Frias H.M.R.Goncalves R.F.P.Pereira s.C.Nunes M.Armand P.s.André V.de Zea Bermudez R.A.s.Ferreira department of Physics and CICECO-Aveiro Institute of Materials University of Aveiro3810-193AveiroPortugal department of Chemistry and CQ-VR University of Tras-os-Montes e Alto Douro5000-801Vila RealPortugal Instituto de Telecomunicacoes University of Aveiro3810-193AveiroPortugal REQUIMTE Instituto Superior de Engenharia do Porto4200-072PortoPortugal Chemistry Centre and Chemistry department University of Minho4710-057BragaPortugal CICs-Health sciences Research Center and Chemistry department University of Beira Interior6201-001CovilhaPortugal Electrical Energy storage department CIC EnergiguneParque Tecnologico de AlavaMinano01510Spain department of Electrical and Computer Engineering Instituto de TelecomunicacoesInstituto Superior TecnicoUniversidade de Lisboa1049-001LisbonPortugal

The mismatch between the photovoltaic(PV)cells absorption and the solar irradiance on earth is one of the major limitations towards more efficient PV energy *** aspect was addressed by downshifting the solar irradiance on Earth through luminescent down-shifting layers based on lanthanidedoped surface-functionalized ionosilicas(Iss)embedded in poly(methyl methacrylate)(PMMA)coated on the surface of commercial si-based PV *** Is-PMMA hybrid materials exhibit efficient solar radiation harvesting(spectral overlap of^9.5×10^19 photons/(s·m2))and conversion(quantum yield^52%).The direct solar radiation and the down-shifted radiation are partially guided and lost through total internal reflection to the layer edges being unavailable for PV conversion of the coated PV *** tuning the down-shifting layer thickness,it also acts as luminescent solar concentrator enabling the collection of the guided radiation by flexible PV cells applied on the borders of the down-shifting layer leading to an enhancement of the PV energy conversion from^5%(in the case of the single-use of the luminescent down-shifting layer)to^13%comparing with the bare PV *** overall electrical output of the device resulted in an absolute external quantum efficiency increase of^32%for the optimized Eu^3+-based films in the UV spectral region(compared with the bare PV device,which is among the best values reported so far).

关键词： Ionosilicas Lanthanides Photovoltaics Luminescent solar concentrators down-shifting layers silicon photovoltaic cells