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91.
Xianglei Mao George C.-Y. Chan Inhee Choi Vassilia Zorba Richard E. Russo 《Journal of Radioanalytical and Nuclear Chemistry》2017,311(1):121-126
Radionuclide concentrations in wharf roaches inhabiting coastal areas of Honshu, Japan, were investigated in October 2011 and June 2012. Relative high concentrations of 110mAg (2.1–127 Bq kg-wet?1), 134Cs (2.6–61 Bq kg-wet?1), and 137Cs (3.5–92 Bq kg-wet?1) were detected in specimens from the eastern Honshu areas. Significantly lower 137Cs concentrations (0.7–1.6 Bq kg-wet?1) were detected in specimens from western and northern Honshu. The decay-corrected 137Cs concentration was significantly inversely correlated with the distance from the Fukushima Dai-ichi Nuclear Power Plant. Thus, wharf roach may serve as a good bioindicator for monitoring radioactive contamination of its habitats. 相似文献
92.
This study investigated the organic and inorganic constituents of healthy leaves and Candidatus Liberibacter asiaticus (CLas)-inoculated leaves of citrus plants. The bacteria CLas are one of the causal agents of citrus greening (or Huanglongbing) and its effect on citrus leaves was investigated using laser-induced breakdown spectroscopy (LIBS) combined with chemometrics. The information obtained from the LIBS spectra profiles with chemometrics analysis was promising for the construction of predictive models to identify healthy and infected plants. The major, macro- and microconstituents were relevant for differentiation of the sample conditions. The models were then applied to different inoculation times (from 1 to 8 months). The models were effective in the classification of 82-97% of the diseased samples with a 95% significance level. The novelty of this method was in the fingerprinting of healthy and diseased plants based on their organic and inorganic contents. 相似文献
93.
The alumina contribution to CO oxidation in the absence of O2 on metal oxide supported catalysts was investigated by CO TPR and in-situ FTIR and DRIFT studies up to 800 °C. These tests were performed on two Al2O3 supported catalysts (1 wt.% Pt/La/γ-Al2O3 and 8 wt.% Cu/γ-Al2O3) and on two corresponding alumina supports (5 wt.% La2O3 stabilised γ-Al2O3 and high mechanical resistant spherical γ-Al2O3 particles). The quantitative determination of CO consumption and CO2 and H2 formation on the alumina supports was in agreement with a WGS reaction occurring between surface OH and CO with a predominantly 2:1 stoichiometry. In the CO TPR of metal oxide supported catalysts, in addition to the reduction of the metal, a WGS reaction took place with enhanced kinetics. This enhancement was the result of a CO spillover phenomenon from the metal to alumina hydroxyls. This phenomenon significantly affected the evaluation of the reduction degree of the supported metal and could not be neglected in the subsequent calculations. 相似文献
94.
95.
96.
Ohne Zusammenfassung 相似文献
97.
Olga Bortolini Beatrice Russo Giovanni Sindona Amedeo Tocci 《Tetrahedron letters》2007,48(40):7125-7128
1,3-Dipolar cycloadditions of nitrones with alkenes afforded the corresponding isoxazolidines in ionic liquids in the presence of Er(OTf)3. The ionic liquid and the catalyst are recycled up to five times without any specific treatment or loss of activity. Extension of the procedure to the synthesis of isoxazolidinyl nucleosides has been investigated. 相似文献
98.
G.M. Russo 《Polymer Degradation and Stability》2007,92(10):1925-1933
The effect of multiple extrusions on nanostructure and properties of nylon 6 nanocomposites was investigated. Nanocomposites at different silicate loadings were produced by melt compounding and submitted to further reprocessing by using single and twin screw extruders. Rheological, morphological and mechanical analyses were carried out on as-produced and reprocessed samples in order to explore the influence of the number and the type of extrusion cycles on silicate nanodispersion.Rheological measurements, correlated to TEM analyses, were used to probe the nanoscale arrangement developed with the reprocessing as well as the thermo-mechanical degradation involving both the neat matrix and the organoclay. The results have shown that the reprocessing by single screw extruder can modify the initial morphology since the re-agglomeration of the silicate layers can occur. On the other hand, a better nanodispersion was observed in the hybrids reprocessed by twin screw extruder. This was attributed to the additional mechanical stresses able to realizing a dispersive mixing that contributes to avoid re-agglomeration phenomena. The high shear stresses produced with twin screw geometry determined also a significant degradation of neat matrix, principally based on chain scission mechanism.A strong correlation between the rheological behaviour and mechanical properties was observed and all as-produced and reprocessed hybrids showed a substantial enhancement in tensile modulus with the adding of silicate. However, the entity of performance enhancements displayed by the reprocessed hybrids was found to be highly dependent on the degradation of both organoclay and polymer matrix as well as the silicate amount, the number and the type reprocessing. 相似文献
99.
Paul S. Russo Mary J. Saunders L.Mark DeLong Scott Kuehl Kenneth H. Langley Robert W. Detenbeck 《Analytica chimica acta》1986
The potential of zero-angle depolarized scattering for measuring the size distributions of optically anisotropic particles is considered. To illustrate the method, an analysis of Fluon, a teflon latex suspension, is presented. Homodyne correlation functions having signal-to-noise characteristics every bit as good as conventional unpolarized finite-angle measurements enabled confident application of a smoothed exponential sampling algorithm to obtain the decay rate distribution, which was converted to a size distribution with certain approximations. The size distribution obtained from light scattering agrees well with that from electron microscopy. 相似文献
100.
Communicated by K. R. Rajagopal 相似文献