Radiative parameters for some transitions in the spectrum of Ag ii     

J. Campos  M. Ortiz  R. Mayo  E. Biémont †  P. Quinet  K. Blagoev  G. Malcheva 《Monthly notices of the Royal Astronomical Society》2005,363(3):905-910

Radiative parameters for transitions depopulating the levels belonging to the 4d⁸5s², 4d⁹6s and 4d⁹5d configurations of Ag  ii have been obtained from a combination of theoretical lifetimes and experimental branching fractions. On the experimental side, a laser-produced plasma was used as a source of Ag⁺ ions. The light emitted by the plasma was analysed by a grating monochromator coupled with a time-resolved optical multichannel analyser system. Spectral response calibration of the experimental system was performed using a deuterium lamp in the wavelength range from 200 to 400 nm, and a standard tungsten lamp in the range from 350 to 600 nm. The transition probabilities were obtained from measured branching ratios and theoretical radiative lifetimes of the corresponding states calculated with a relativistic Hartree–Fock approach including core-polarization effects and configuration interaction in an extensive way. Theoretical and experimental data have been compared and the new data have also been compared with the few previous results available in the literature.  相似文献   

Robust system identification of an irrigation main canal     

R. Rivas Perez  V. Feliu Batlle  L. Sanchez Rodriguez 《Advances in water resources》2007

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Communicating human health risks associated with disinfection by-products in drinking water supplies: a fuzzy-based approach   总被引：1，自引：2，他引：1  

Rehan Sadiq  Manuel J. Rodriguez  Syed A. Imran  Homayoun Najjaran 《Stochastic Environmental Research and Risk Assessment (SERRA)》2007,21(4):341-353

Chlorine used for the disinfection of water supplies can react with naturally occurring organic compounds and form potentially harmful disinfection by-products (DBPs). A risk index for two regulated groups of chlorinated DBPs—trihalomethanes (THMs) and haloacetic acids (HAAs), using fuzzy C-means (FCM) clustering algorithm and fuzzy rule-based modeling is proposed for risk communication. The proposed index evaluates the cancer and non-cancer risks individually for THMs and HAAs using the FCM algorithm. Subsequently, two different fuzzy rule-bases were used to evaluate the overall risk-index based on cancer and non-cancer risks. The overall risk-index will provide drinking water utilities with an effective communication tool for communicating aggregated water quality compliance. Simulated DBP occurrence data obtained from the City of Quebec, Canada, is used to demonstrate the application of this methodology.  相似文献   

Climate change and population history in the Pacific Lowlands of Southern Mesoamerica   总被引：1，自引：0，他引：1  

Hector Neff  Deborah M. Pearsall  John G. Jones  Brbara Arroyo de Pieters  Dorothy E. Freidel 《Quaternary Research》2006,65(3):390-400

Core MAN015 from Pacific coastal Guatemala contains sediments accumulated in a mangrove setting over the past 6500 yr. Chemical, pollen, and phytolith data, which indicate conditions of estuarine deposition and terrigenous inputs from adjacent dry land, document Holocene climate variability that parallels the Maya lowlands and other New World tropical locations. Human population history in this region may be driven partly by climate variation: sedentary human populations spread rapidly through the estuarine zone of the lower coast during a dry and variable 4th millennium B.P. Population growth and cultural florescence during a long, relatively moist period (2800–1200 B.P.) ended around 1200 B.P., a drying event that coincided with the Classic Maya collapse.  相似文献   

XMM–Newton observations of PSR B1259−63 near the 2004 periastron passage     

M. Chernyakova †  A. Neronov  A. Lutovinov  J. Rodriguez  S. Johnston 《Monthly notices of the Royal Astronomical Society》2006,367(3):1201-1208

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Kilometer-wave type III burst: Harmonic emission revealed by direction and time of arrival     

Hector Alvarez  Fred T. Haddock  William H. Potter 《Solar physics》1974,34(2):413-420

A type III solar burst was observed at seven frequencies between 3.5 MHz and 80 kHz by the Michigan experiment aboard the IMP-6 satellite. From the data we can determine burst direction-of-arrival as well as time-of-arrival. We predict these quantities using simple models whose parameters we vary to obtain a good fit to the observations. We find that between 3.5 MHz and 230 kHz the observed radiation was emitted at the fundamental of the local plasma frequency while below 230 kHz it was emitted at the second harmonic. The exciter particles that produced the burst onset and burst peak have velocities of 0.27 and 0.12, respectively, in units of the velocity of light.  相似文献   

Reevaluation of the earthquakes of 10 March and 19 May 1951 in southern Spain     

A.?UdíasEmail author  D.?Mu?oz  E.?Buforn  C.?Sanz?de?Galdeano  C.?del?Fresno  I.?Rodriguez 《Journal of Seismology》2005,9(1):99-110

Damage and parameters of the earthquakes of 10 March and 19 May 1951 in southern Spain have been reevaluated. Data available do not allow accurate depth determinations and previous estimates of larger depths are not confirmed, so depths have been fixed at 30 km for both shocks. Magnitudes (Ms) have been determined as 5.4 and 5.6, respectively. Intensities estimated at 22 and 29 sites from contemporary documentary sources give maximum values of VI–VII and VI (EMS Scale), lower than previous estimates. The focal mechanism for the May shock is right-lateral strike-slip with a normal component of motion, with planes with strikes 273° and 169°; seismic moment 1.9 × 10¹⁶ Nm and dimension 6 km (radius of circular fault). Shocks are located near the boundary between the Iberian plateau and the Guadalquivir Basin and may be related to faults connected with this boundary.  相似文献   

Estimating runoff from a glacierized catchment using natural tracers in the semi‐arid Andes cordillera          下载免费PDF全文

Maximiliano Rodriguez  Nils Ohlanders  Francesca Pellicciotti  Mark W. Williams  James McPhee 《水文研究》2016,30(20):3609-3626

This paper presents a methodology for hydrograph separation in mountain watersheds, which aims at identifying flow sources among ungauged headwater sub‐catchments through a combination of observed streamflow and data on natural tracers including isotope and dissolved solids. Daily summer and bi‐daily spring season water samples obtained at the outlet of the Juncal River Basin in the Andes of Central Chile were analysed for all major ions as well as stable water isotopes, δ¹⁸O and δD. Additionally, various samples from rain, snow, surface streams and exfiltrating subsurface water (springs) were sampled throughout the catchment. A principal component analysis was performed in order to address cross‐correlation in the tracer dataset, reduce the dimensionality of the problem and uncover patterns of variability. Potential sources were identified in a two‐component U‐space that explains 94% of the observed tracer variability at the catchment outlet. Hydrograph separation was performed through an Informative‐Bayesian model. Our results indicate that the Juncal Norte Glacier headwater sub‐catchment contributed at least 50% of summer flows at the Juncal River Basin outlet during the 2011–2012 water year (a hydrologically dry period in the Region), even though it accounts for only 27% of the basin area. Our study confirms the value of combining solute and isotope information for estimating source contributions in complex hydrologic systems, and provides insights regarding experimental design in high‐elevation semi‐arid catchments. The findings of this study can be useful for evaluating modelling studies of the hydrological consequences of the rapid decrease in glacier cover observed in this region, by providing insights into the origin of river water in basins with little hydrometeorological information. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

Reply to ��Comment on Sousa, M.L. and Costa, A.C., ��ground-motion scenarios consistent with probabilistic seismic hazard disaggregation analysis. Application to Mainland Portugal��?�� by Jo?o F. B. D. Fonseca and Susana P. Vilanova     

Maria Lu��sa Sousa  Alfredo Campos Costa 《Bulletin of Earthquake Engineering》2011,9(4):1297-1307

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The Itaja�� foreland basin: a tectono-sedimentary record of the Ediacaran period, Southern Brazil     

M. A. S. Basei  C. O. Drukas  A. P. Nutman  K. Wemmer  L. Dunyi  P. R. Santos  C. R. Passarelli  M. C. Campos Neto  O. Siga Jr  L. Osako 《International Journal of Earth Sciences》2011,100(2-3):543-569

The Itajaí Basin located in the southern border of the Luís Alves Microplate is considered as a peripheral foreland basin related to the Dom Feliciano Belt. It presents an excellent record of the Ediacaran period, and its upper parts display the best Brazilian example of Precambrian turbiditic deposits. The basal succession of Itajaí Group is represented by sandstones and conglomerates (Baú Formation) deposited in alluvial and deltaic-fan systems. The marine upper sequences correspond to the Ribeir?o Carvalho (channelized and non-channelized proximal silty-argillaceous rhythmic turbidites), Ribeir?o Neisse (arkosic sandstones and siltites), and Ribeir?o do Bode (distal silty turbidites) formations. The Apiúna Formation felsic volcanic rocks crosscut the sedimentary succession. The Cambrian Subida leucosyenogranite represents the last felsic magmatic activity to affect the Itajaí Basin. The Brusque Group and the Florianópolis Batholith are proposed as source areas for the sediments of the upper sequence. For the lower continental units the source areas are the Santa Catarina, S?o Miguel and Camboriú complexes. The lack of any oceanic crust in the Itajaí Basin suggests that the marine units were deposited in a restricted, internal sea. The sedimentation started around 600?Ma and ended before 560?Ma as indicated by the emplacement of rhyolitic domes. The Itajaí Basin is temporally and tectonically correlated with the Camaqu? Basin in Rio Grande do Sul and the Arroyo del Soldado/Piriápolis Basin in Uruguay. It also has several tectono-sedimentary characteristics in common with the African-equivalent Nama Basin.  相似文献