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91.
Marina De Nicola Carmela Gambardella Sandro M. Guarino 《Marine pollution bulletin》1992,24(12):619-621
Separate and interactive pollution effects of Cd and Zn on electrophoretically-detected allozyme frequencies of the different genotypes at PGI and PGM loci were studied in Idotea baltica.
Differential survivorship of PGM genotypes was detected in the presence of the single or combined pollutants, while no effect was observed for PGI. Cadmium decreased heterozygosity while zinc or Cd + Zn increased it, suggesting an antithetic action of the two metals and the prevalence of zinc. 相似文献
92.
Sandro da Silva Fernandes 《Celestial Mechanics and Dynamical Astronomy》2003,87(3):307-315
In this paper the new approach for the integration theory of the canonical version of Hori method recently proposed is extended to the non-canonical one. It will be shown that the non-homogeneous ordinary differential equation with an auxiliary parameter t* associated with the mth order equation of the algorithm can also be replaced by a non-homogeneous partial differential equation in the time t. Using a generalized canonical approach, the general algorithm proposed by Sessin is then revised; as well as the Lagrange variational equations for the non-canonical version of Hori method. A simplified algorithm derived from Sessin's algorithm is presented for non-linear oscillations problem. 相似文献
93.
Vincenzo Artale Sandro Calmanti Adriana Carillo Alessandro Dell’Aquila Marine Herrmann Giovanna Pisacane Paolo M. Ruti Gianmaria Sannino Maria Vittoria Struglia Filippo Giorgi Xunqiang Bi Jeremy S. Pal Sara Rauscher 《Climate Dynamics》2010,35(5):721-740
We present an atmosphere–ocean regional climate model for the Mediterranean basin, called the PROTHEUS system, composed by the regional climate model RegCM3 as the atmospheric component and by a regional configuration of the MITgcm model as the oceanic component. The model is applied to an area encompassing the Mediterranean Sea and compared to a stand-alone version of its atmospheric component. An assessment of the model performances is done by using available observational datasets. Despite a persistent bias, the PROTHEUS system is able to capture the inter-annual variability of seasonal sea surface temperature (SST) and also the fine scale spatio-temporal evolution of observed SST anomalies, with spatial correlation as high as 0.7 during summer. The close inspection of a 10-day strong wind event during the summer of 2000 proves the capability of the PROTHEUS system to correctly describe the daily evolution of SST under strong air–sea interaction conditions. As a consequence of the model’s skill in reproducing observed SST and wind fields, we expect a reliable estimation of air–sea fluxes. The model skill in reproducing climatological land surface fields is in line with that of state of the art regional climate models. 相似文献
94.
Paolo Saracco Sandro D'Odorico Alan Moorwood Jean G. Cuby 《Astrophysics and Space Science》2001,276(2-4):991-998
Deep J- and K
s-band images covering a 5 × 5 arcmin area centred on the NTT Deep Field have been obtained during the Science Verification
of SOFI at the NTT. These images were made available via the Web in early June, 1998. The preliminary results we have obtained
by the analysis of these data are the following: (i) the counts continue to rise with no evidence of a turnover or of a flattening
down to the limits of the survey (K
s = 22.5 and J = 24 mag); (ii) we find a slope d log(N)/dm≈ 0.37, in agreement with most of the faintest surveys but much steeper than the Hawaii survey; (iii) fainter than K
s ≈ 19and J ≈ 20 mag, the median J-K colour of galaxies shows a break in its reddening trend turning toward bluer colours; (iv) faint bluer galaxies also display
a larger compactness index, and a smaller apparent size.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
95.
List of papers from other journals 相似文献
96.
List of papers from other journals 相似文献
97.
98.
Atomic-scale mechanisms of plastic deformation in orthoenstatite, MgSiO3 are studied by computer simulation methods. The combined use of metadynamics and molecular dynamics allows a direct observation
of the structural changes during the creation of stacking faults in the (100) plane. A sequence of slip deformations in two
different (100) planes at P = 15 GPa and T = 1,000 K reveals a probable transformation mechanism for the ortho- to high-pressure clinopyroxene transition. Each of the
observed slips consists of at least four partial deformations crossing high-energy intermediate structures. In agreement with
experimental studies, both (100)[010] and (100)[001] slip systems are activated in the deformation process. The observation
of a dominant (100)[001] single slip system in pyroxenes may be related to the fact that high-energy intermediate dislocations
with (100)[010] component are not stable on geological or experimental timescales. 相似文献
99.
Sandro FADDA Alessandro RIVOLDINI Ignazio CAU 《Geostandards and Geoanalytical Research》1995,19(1):41-54
The microwave oven acid digestion technique has been routinely applied to the ICP-MS multielement analysis of whole powdered coal. Samples were treated with a mixture of HF/aqua regia/HClO4 in closed Teflon PFA vessels without any pre-treatment. Complete dissolution of the coal matrix is not required, but only one that results in quantitative and reproducible recovery of more than 40 trace elements with minimum digestion time, minimum use of reagents and minimal operator attendance. The precision of the analysis as well as the repeatability of the sample preparation procedure and precision of instrumental measurements have been evaluated. Eight coal standards, including NBS SRM 1632b, 3 South Africa Reference Materials (SARMs) 18 to 20 and 4 USA ARs 1800 to 1803 were analysed in this manner providing data for all the 14 rare earth elements along with others of geochemical interest, technological relevance as well as environmental and health concern. The results, from the ppb level to several ppm, are discussed for all the elements including detection and quantification limits, precision and accuracy. In general, good agreement was achieved with the certified and/or available published values. 相似文献
100.
Sandro Da Silva Fernandes 《Celestial Mechanics and Dynamical Astronomy》1995,62(4):305-321
Some classic expansions of the elliptic motion — cosmE and sinmE — in powers of the eccentricity are extended to highly eccentric orbits, 0.6627...<e<1. The new expansions are developed in powers of (e–e*), wheree* is a fixed value of the eccentricity. The coefficients are given in terms of the derivatives of Bessel functions with respect to the eccentricity. The expansions have the same radius of convergence (e*) of the extended solution of Kepler's equation, previously derived by the author. Some other simple expansions — (a/r), (r/a), (r/a) sinv, ..., — derived straightforward from the expansions ofE, cosE and sinE are also presented. 相似文献