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1.
Europium (Eu+) ions were confined in a Paul trap and detected by non-destructive method. Storage time of Eu+ ions achieved in vacuum was improved by orders of magnitude employing buffer gas cooling. The experimentally detected signal
was fitted to the ion response signal and the total number of ions trapped was estimated. It is found that the peak signal
amplitude as well as the product of FWHM and the peak signal amplitude is proportional to the total number of trapped ions.
The trapped ion secular frequency was swept at different rates and its effect on the absorption line profile was studied both
experimentally and theoretically. 相似文献
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L. de Arcangelis H. J. Herrmann M. Kolb René Thomas C. Amitrano L. Peliti M. Saber G. Weisbuch Sara A. Solla F. Bagnoli A. Francescato R. Livi S. Ruffo Pablo Tamayo Michel Droz Peter Jörg Plath S. Romano Yves Pomeau Stéphane Zaleski D. Stauffer Luciano R. da Silva Alex Hansen Stéphane Roux Antonio Coniglio B. Derrida Henrik Flyvbjerg Naeem Jan Dietrich Stauffer Peter Grassberger A. Zippelius K. E. Kurten Werner Krauth Jean -Pierre Nadal Marc Mézard Per Bak Chao Tang Itzhak Webman M. L. Martins H. F. V. Resende C. Tsallis A. C. N. Magalhaes 《Journal of statistical physics》1989,55(5-6):1333-1359
4.
Comparison of analytical tools and biological assays for detection of paralytic shellfish poisoning toxins 总被引:1,自引:0,他引:1
A. R. Humpage V. F. Magalhaes S. M. Froscio 《Analytical and bioanalytical chemistry》2010,397(5):1655-1671
The paralytic shellfish poisoning toxins (PSTs) were, as their name suggests, discovered as a result of human poisoning after
consumption of contaminated shellfish. More recently, however, the same toxins have been found to be produced by freshwater
cyanobacteria. These organisms have worldwide distribution and are common in our sources of drinking water, thus presenting
another route of potential human exposure. However, the regulatory limits for PSTs in drinking water are considerably lower
than in shellfish. This has increased the need to find alternatives to the mouse bioassay, which, apart from being ethically
questionable, does not have a limit of detection capable of detecting the PSTs in water at the regulated concentrations. Additionally,
the number of naturally occurring PSTs has grown substantially since saxitoxin was first characterised, markedly increasing
the analytical challenge of this group of compounds. This paper summarises the development of chromatographic, toxicity, and
molecular sensor binding methodologies for detection of the PSTs in shellfish, cyanobacteria, and water contaminated by these
toxins. It then summarises the advantages and disadvantages of their use for particular applications. Finally it recommends
some future requirements that will contribute to their improvement for these applications. 相似文献
5.
The present work offers new equations for phase evaluation in measurements. Several phase shifting equations with an arbitrary but constant phase shift between captured intensity signs are proposed. The equations are similarly derived as the so-called Carré equation. The idea is to develop a generalization of Carré equation that is not restricted to four images. Errors and random noise in the images cannot be eliminated, but the uncertainty due to their effects can be reduced by increasing the number of observations. An experimental analysis of the mistakes of the technique was made, as well as a detailed analysis of mistakes of the measurement. The advantages of the proposed equation are its precision in the measures taken, speed of processing and the immunity to noise in signs and images. 相似文献
6.
Synthesis of a Benzannulated Pyrrolizidine by a Copper‐Catalyzed Intramolecular α‐Arylation Reaction
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Flavia Magalhaes Araujo Wellington Martins Ventura Jason Guy Taylor 《Helvetica chimica acta》2014,97(4):569-573
A synthetic route to the pyrrolo[1,2‐a]indole ring system (benzannulated pyrrolizidine) involving a base‐induced intramolecular aza‐Michael reaction as the key C? N bond‐forming penultimate step, followed by a Cu‐catalyzed intramolecular α‐arylation reaction, to provide the tricyclic framework over six steps is described. 相似文献
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Eliene O Kozlowski Paula C Lima Cristina P Vicente Tito Lotufo Xingfeng Bao Kazuyuki Sugahara Mauro SG Pavão 《BMC biochemistry》2011,12(1):1-2
After the publication of the work entitled "Dermatan sulfate in tunicate phylogeny: Order-specific sulfation pattern and the effect of [→4IdoA(2-Sulfate)β-1→3GalNAc(4-Sulfate)β-1→] motifs in dermatan sulfate on heparin cofactor II activity", by Kozlowski et al., BMC Biochemistry 2011, 12:29, we found that the legends to Figures 2 to 5 contain serious mistakes that compromise the comprehension of the work. This correction article contains the correct text of the legends to Figures 2 to 5. 相似文献
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An unsusual 2,3 cyclopentaindanone (III) was obtained, presumably as a result of a mixed Michael and Stobbe condensation, in the course of an attempted Robinson annulation. 相似文献
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Fabio da Silva Bortoli Carlos Frajuca Sergio Turano de Sousa Arlette de Waard Nadja Simao Magalhaes Odylio Denys de Aguiar 《Brazilian Journal of Physics》2016,46(3):308-315
SCHENBERG is a resonant-mass gravitational wave detector built in Brazil. Its spherical antenna, weighting 1.15 t, is connected to the outside world by a suspension system whose main function is to attenuate the external seismic noise. In this work, we report how the system was modeled using finite elements method. The model was validated on experimental data. The simulation showed that the attenuation obtained is of the order of 260 dB, which is sufficient for decreasing the seismic noise below the level of the thermal noise of the detector operating at 50 mK. 相似文献
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