A 3-dimensional calculation of the atmospheric neutrino fluxes     

G. Battistoni  A. Ferrari  P. Lipari  T. Montaruli  P. R. Sala  T. Rancati 《Astroparticle Physics》2000,12(4):315-333

An extensive 3-dimensional Monte Carlo calculation of the atmospheric neutrino flux is in progress with the FLUKA Monte Carlo code. The results are compared to those obtained under the 1-dimensional approximation, where secondary particles and decay products are assumed to be collinear to the primary cosmic ray, as usually done in most of the already existing flux calculations. It is shown that the collinear approximation gives rise to a wrong angular distribution of neutrinos, essentially in the Sub-GeV region. However, the angular smearing introduced by the experimental inability of detecting recoils in neutrino interactions with nuclei is large enough to wash out, in practice, most of the differences between 3-dimensional and 1-dimensional flux calculations. Therefore, the use of the collinear approximation should not have introduced a significant bias in the determination of the flavor oscillation parameters in current experiments.  相似文献   

Speckle observations with PISCO in Merate – I. Astrometric measurements of visual binaries in 2004     

M. Scardia  J.-L. Prieur  M. Sala  M. Ghigo  L. Koechlin  E. Aristidi  F. Mazzoleni 《Monthly notices of the Royal Astronomical Society》2005,357(4):1255-1266

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Molecular investigations into pollutant impact on roundnose grenadier (C. rupestris) and transplanted common mussel (M. edulis) in Skagerrak, the North Sea     

Lars Frlin  David R. Livingstone  Kerstin Magnusson  Laurence D. Peters  Montserrat Sol  Anders Sjlin  ke Granmo 《Marine environmental research》1996,42(1-4)

The use of a suite of different biochemical markers in the deep sea fish Roundnose grenadier and caged common mussels, and analyses of contaminant levels in the mussels, indicate that Skagerrak are more polluted than waters around the Faroe Islands. In Roundnose, induction of ethoxyresorufin-O-deethylase (EROD) is consistent with increased benzo(a)pyrene hydroxylase (BPH) in mussels and elevated levels of polynuclear aromatic hydrocarbons (PAHs) in mussels and sediment from Skagerrak. This evidence of a large-scale environmental impact of pollutants should lead to further efforts to decrease transport into, and deposition of, waste compounds in the Skagerrak area.  相似文献   

Speckle observations with PISCO in Merate – III. Astrometric measurements of visual binaries in 2005 and scale calibration with a grating mask     

M. Scardia  J.-L. Prieur  L. Pansecchi  R. W. Argyle  S. Basso  M. Sala  M. Ghigo  L. Koechlin  E. Aristidi 《Monthly notices of the Royal Astronomical Society》2007,374(3):965-978

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Stratigraphy of the Middle Devonian boundary: Formal definition of the susceptibility magnetostratotype in Germany with comparisons to sections in the Czech Republic, Morocco and Spain     

Brooks B. Ellwood  Jenaro L. García-Alcalde  Ahmed El Hassani  Jindrich Hladil  Francisco M. Soto  Montserrat Truyls-Massoni  Karsten Weddige  Leona Koptikova 《Tectonophysics》2006,418(1-2):31

One major difficulty in geology is high-resolution correlation among widely separated sections, especially in the Paleozoic where magnetostratigraphy polarity is not well established because rocks are often remagnetized, where critical biostratigraphic zonation may be poor or lacking, or where structural complexities make correlations very difficult. To address this problem, we have been using magnetostratigraphy susceptibility measurements. Here, we report our work from the Middle Devonian in Europe and North Africa. The Middle Devonian (Emsian–Eifelian) global boundary stratotype section and point (GSSP), located in the Eifel Hills, western Germany, was ratified by the International Subcommission on Stratigraphy in 1985, after careful evaluation of the biostratigraphy for this and many other sections. The boundary interval has been characterized using biostratigraphy, and the beginning of the Eifelian stage has been specifically defined by the first occurrence of the conodont Polygnathus costatus partitus. We have collected the Eifel Hills section for magnetic susceptibility (MS) measurement and here we establish it as the magnetostratotype for the Emsian–Eifelian stage boundary, by formally defining the magnetostratigraphy susceptibility for the section. We then collected, measured and compared the magnetostratotype to four other sections for which conodont biostratigraphy has been studied and where P. costatus partitus is present; two Emsian–Eifelian sections in Morocco and two sections in the Czech Republic (including the Emsian–Eifelian parastratotype). Finally, we have measured the MS for the El Puerto Creek section in the Cantabrian Mountains of Spain and identified the location of the Emsian–Eifelian boundary within the section based on MS comparison to the GSSP in conjunction with excellent biostratigraphic indicators, primarily brachiopods. While the conodont zonation in the El Puerto Creek section is poorly defined, we believe that the correspondence between the MS and biostratigraphy in the section allows the identification of the Emsian–Eifelian boundary. These results indicate that this method can be successfully applied to marine sequences where ambiguities in correlation exist.  相似文献   

Sediment diffusive fluxes of Fe,Mn, and P in a eutrophic lake: Contribution from lateral vs bottom sediments   总被引：3，自引：0，他引：3  

Nelson Belzile  Jaime Pizarro  Montserrat Filella  Jacques Buffle 《Aquatic Sciences - Research Across Boundaries》1996,58(4):327-354

Water column data and porewater profiles are used to study the chemical evolution with time and with depth of a eutrophic lake. By using different approaches, diffusion fluxes for dissolved iron, manganese and phosphate are calculated and used to describe the processes occurring at the sediment-water interface as well as in the hypolimnion of the lake. These data are used in the elaboration of a qualitative model to describe the chemical behaviour of the sedimentary interface of an anoxic lake with emphasis on the Fe/P/S system. Acorona model is proposed to explain the evolution with time of the diffusion process by estimating the relative contribution of bottom and lateral sediment surfaces to the total fluxes of dissolved elements diffusing from the sediment to the overlying water. As the hypolimnion becomes more anoxic, it has been observed that lateral sediment surfaces (16 to 10 meters in depth) represents a larger supplier of diffusing dissolved components than the bottom sediment portion (bottom to 18 meters).  相似文献   

Computer simulation of the low-molecular-weight inorganic species distribution of antimony(III) and antimony(V) in natural waters     

Montserrat Filella  Peter M. May 《Geochimica et cosmochimica acta》2003,67(21):4013-4031

Computer speciation models of antimony in aqueous, multicomponent solutions of environmental and biological interest have been developed. Antimony is an element of increasing environmental significance but one whose chemical speciation has not previously been modelled in any comprehensive way. The available thermodynamic data have been critically evaluated and entered into a thermodynamic database. The JESS suite of computer programs has been used to develop the thermodynamically-consistent mass balance equations used for modelling purposes. The calculated speciation distributions successfully account for some but not all key known properties of antimony in natural waters. It is believed that the main difference is most likely due to kinetic factors.  相似文献   

Mineral fibres and environmental monitoring:A comparison of different analytical strategies in New Caledonia     

Jasmine Rita Petriglieri  Christine Laporte-Magoni  Peggy Gunkel-Grillon  Mario Tribaudino  Danilo Bersani  Orietta Sala  Monika Le Mestre  Ruggero Vigliaturo  Nicola Bursi Gandolfi  Emma Salvioli-Mariani 《地学前缘(英文版)》2020,11(1):189-202

Covered by ultrabasic units for more than a third of its surface,the New Caledonia(South West Pacific)is one of the largest world producers of Ni-ore from lateritic deposits.Almost all outcrops of geological units and open mines contain serpentine and amphibole,also as asbestos varieties.In this geological context,in which weathering processes had a great contribution in the production and dispersion of mineral fibres into the environment,the development of a routinely analytical strategy,able to discriminate an asbestiform fibre from a non-harmful particle,is a pivotal requisite.However,the acquisition of all these parameters is necessary for determining the risk associated to fibres exposition.A multidisciplinary routinely approach,based on the use of complementary simply-to-use but reliable analytical methods is the only possible strategy.In addition,the instrumental apparatus must be easily transportable on the field,directly on the mining site.The employment of specialized tools such as Polarized Light Microscopy associated to Dispersion Staining method(PLM/DS)and portable Raman spectroscopy for identification of environmental asbestos,are proved extremely effective in the improvement of the performance and rapidity of data acquisition and interpretation.Both PLM/DS and handheld Raman devices confirmed to be discriminant in the detection and characterization of asbestos fibres for both serpentine and amphibole.Furthermore,these techniques proved extremely effective even in the presence of strongly fibrous and altered samples.  相似文献   

Sediment segregation by biodiffusing bivalves   总被引：1，自引：0，他引：1  

F. Montserrat  C. Van Colen  P. Provoost  M. Milla  M. Ponti  K. Van den Meersche  T. Ysebaert  P.M.J. Herman 《Estuarine, Coastal and Shelf Science》2009,83(4):379-391

The selective processing of sediment fractions (sand and mud; >63 μm and ≤63 μm median grain size) by macrofauna was assessed using two size classes of inert, UV-fluorescent sediment fraction tracers (luminophores). The luminophores were applied to the sediment surface in 16 m² replicated plots, defaunated and control, and left to be reworked by infauna for 32 days. As the macrofaunal assemblage in the ambient sediment and the control plots was dominated by the common cockle Cerastoderma edule, this species was used in an additional mesocosm experiment. The diversity, abundance and biomass of the defaunated macrobenthic assemblage did not return to control values within the experimental period. Both erosion threshold and bed elevation increased in the defaunated plots as a response to the absence of macrofauna and an increase in microphytobenthos growth. In the absence of macrobenthos, we observed an accretion of 7 mm sediment, containing ca. 60% mud. Image analysis of the vertical distribution of the different luminophore size classes showed that the cockles preferentially mobilised fine material from the sediment, thereby rendering it less muddy and effectively increasing the sand:mud ratio. Luminophore profiles and budgets of the mesocosm experiment under “no waves–no current” conditions support the field data very well.  相似文献   

Antimony in the environment: A review focused on natural waters. III. Microbiota relevant interactions   总被引：1，自引：0，他引：1  

Montserrat Filella  Nelson Belzile  Marie-Claire Lett 《Earth》2007,80(3-4):195-217

Antimony is ubiquitously present in the environment as a result of natural processes and human activities. Antimony is not considered to be an essential element for plants or animals. In this third review paper on the occurrence of antimony in natural waters, the interactions of antimony with microbiota are discussed in relation to its fate in natural waters. This paper covers the following aspects: occurrence in microbiota, uptake transport mechanisms, pathways of Sb(III) removal from cells involved in antimony tolerance, oxidation and reduction of antimony by living organisms, phytochelatin induction and biomethylation. This review is based on a careful and systematic examination of a comprehensive collection of papers on the above mentioned aspects of the subject. All data are quoted from the original sources. Relatively little existing information falls within the strict scope of this review and, when relevant, discussion on the interactions of antimony with reference microorganisms, such as Escherichia coli, Saccharomyces cerevisiae and different protozoan parasites of the genus Leishmania, has been included.  相似文献