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排序方式: 共有423条查询结果,搜索用时 15 毫秒
191.
Comparative analysis of the secondary electron yield from carbon nanoparticles and pure water medium
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Leskinen Anumaija Salminen-Paatero Susanna Gautier Celine Räty Antti Tanhua-Tyrkkö Merja Fichet Pascal Kekki Tommi Zhang Wenzhong Bubendorff Jacques Laporte Elodie Lambrot Gabriel Brennetot René 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(3):1303-1316
Journal of Radioanalytical and Nuclear Chemistry - This paper reports the results obtained during an intercomparison exercise for the determination of difficult to measure radionuclides in... 相似文献
196.
Nick Schiavon Angela Celauro Marta Manso Antonio Brunetti Fiammetta Susanna 《Applied Physics A: Materials Science & Processing》2013,113(4):865-875
A simple, fast, and nondestructive analytical methodology combining X-ray Fluorescence (EDXRF) and Back-scattered Electron Microscopy coupled with Energy Dispersive Spectroscopy (BSEM+EDS) has been applied to characterize the alloy’s composition of ex-votos metal statuettes of unknown provenance and age stored in the Museum of Évora in Southern Portugal, and to compare it with Iron-Age artefacts of similar typology recovered from the well-known Phoenician settlement (7th century BC) of Alcàcer do Sal located about 50 km W of Évora. The aim of the study was two-fold: (a) to confirm the age and provenance of the bronzes from the Alcàcer settlement; (b) to assess whether the combined archaeometric approach could shed light on the interaction between local (Iberian peninsula) and allochtonous (Phoenician) technological know-how and on how the “Orientalizing” Phoenician influence had been modulated locally in the making of metal artifacts. In this respect, for comparative purposes, selected bronze statuettes displaying “Orientalizing” features of inferred Phoenician origin from the Nuragic collection of the National Archaeological Museum in Cagliari and the G.A. Sanna Museum of Sassari, Sardinia, were also analyzed by EDXRF. Results indicate that all statuettes are made of an alloy of Cu/Sn or Cu/Sn/Pb with variable Sn and Pb content. The presence and content of Pb and of Fe (the latter always >0.05 %) in the alloy suggest a production technology involving the smelting of ferrous minerals and/or the use of reducing firing conditions with locally available Pb intentionally added as fluxing agent. The alloy’s compositional data is consistent with a provenance of the Évora statuettes from the known Phoenician settlement of Alcàcer do Sal in Southern Portugal. 相似文献
197.
Juan Eduardo Resndiz‐Galvn Melissa Romano‐Aguilar Susanna Edith Medellín‐Garibay Rosa del Carmen Miln‐Segovia Alejandro Chevaile‐Ramos Silvia Romano‐Moreno 《Biomedical chromatography : BMC》2019,33(12)
To implement and validate an analytical method by ultra‐performance liquid chromatography–tandem mass spectrometry (UPLC MS/MS) to quantify mycophenolic acid (MPA) in kidney transplant patients. Quantification of MPA was performed in an ACQUITY UPLC H Class system coupled to a Xevo TQD detector and it was extracted from plasma samples by protein precipitation. The chromatographic separation was achieved through an ACQUITY HSS C18 SB column with 0.1% formic acid and acetonitrile (60:40 vol/vol) as mobile phase. The pharmacokinetic parameters were calculated by non‐compartmental analysis of MPA plasma concentrations from 10 kidney transplant patients. The linear range for MPA quantification was 0.2–30 mg/L with a limit of detection of 0.07 mg/L; the mean extraction recovery was 99.99%. The mean intra‐ and inter‐day variability were 2.98% and 3.4% with a percentage of deviation of 8.4% and 6.6%, respectively. Mean maximal concentration of 10 mg/L at 1.5 h, area under the concentration–time curve of 36.8 mg·h/L, elimination half‐life of 3.9 h, clearance of 0.32 L/h/kg and volume of distribution of 1.65 L/kg were obtained from MPA pharmacokinetics profiles. A simple, fast and reliable UPLC–MS/MS method to quantify MPA in plasma was validated and has been applied for pharmacokinetic analysis in kidney transplant patients. 相似文献
198.
This paper describes the structure of the nodal set of segregation profiles arising in the singular limit of planar, stationary, reaction-diffusion systems with strongly competitive interactions of Lotka-Volterra type, when the matrix of the interspecific competition coefficients is asymmetric and the competition parameter tends to infinity. Unlike the symmetric case, when it is known that the nodal set consists of a locally finite collection of curves meeting with equal angles at a locally finite number of singular points, the asymmetric case shows the emergence of spiraling nodal curves, still meeting at locally isolated points with finite vanishing order. © 2019 Wiley Periodicals, Inc. 相似文献
199.
Laura Abatangelo Susanna Terracini 《Journal of Fixed Point Theory and Applications》2011,10(1):147-180
We investigate existence and qualitative behavior of solutions to nonlinear Schr?dinger equations with critical exponent and
singular electromagnetic potentials. We are concerned with magnetic vector potentials which are homogeneous of degree –1,
including the Aharonov–Bohm class. In particular, by variational arguments we prove a result of multiplicity of solutions
distinguished by symmetry properties. 相似文献
200.
This article presents early results from an opinion formation study based on a 76-member panel of U.S. citizens, with comparison
data from a group of 177 nanotechnology experts. While initially similar to the expert group in terms of their perceptions
of the risks, benefits, and need for regulation characterizing several forms of nanotechnology, the first follow-up survey
indicates that the panel is beginning to diverge from the experts, particularly with respect to perceptions of the levels
of various “societal” risks that nanotechnology might present. The data suggest that responding to public concerns may involve
more than attention to physical risks in areas such as health and environment; concerns about other forms of risk actually
appear more salient. 相似文献