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101.
Controlled adsorptive accumulation at the hanging mercury drop electrode enables 0.8–11 × 10?5 M chlordiazepoxide to be quantified by differential-pulse stripping voltammetry with accumulation times of 1–3 min. With 3-min accumulation, the peak current is enhanced 12-fold for 1.0 × 10?7 M chlordiazepoxide compared to the current from differential pulse polarography. The detection limit is 0.9 × 10?9 M for 4-min accumulation. The procedure is applied to spiked human serum after preseparation of the drug on a Sep-Pak C18 cartridge. 相似文献
102.
M R Iesce F Cermola F De Lorenzo I Orabona M L Graziano 《The Journal of organic chemistry》2001,66(13):4732-4735
103.
A pulsed hard X-ray source with shot to shot reproducible spectrum, based on a 4.7 kJ small-chamber Mather-type plasma focus device, is presented. The hard X-ray output spectrum was measured in a single shot basis by differential absorption on metallic plates. The measured spectra have a single dominant peak around 75 keV and a spectral bandwidth covering the 40-150 keV range. A hard X-ray dose of (53±3) μGy per shot was measured on axis at 53 cm from the source, and found to be uniform within a half aperture angle of 6°. 相似文献
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107.
Mapundi Banda Axel Klar Lorenzo Pareschi Mohammed Seaï d. 《Mathematics of Computation》2008,77(262):943-965
A relaxation system based on a Lattice-Boltzmann type discrete velocity model is considered in the low Mach number limit. A third order relaxation scheme is developed working uniformly for all ranges of the mean free path and Mach number. In the incompressible Navier-Stokes limit the scheme reduces to an explicit high order finite difference scheme for the incompressible Navier-Stokes equations based on nonoscillatory upwind discretization. Numerical results and comparisons with other approaches are presented for several test cases in one and two space dimensions.
108.
Feliks Nüske Pter Koltai Lorenzo Boninsegna Cecilia Clementi 《Entropy (Basel, Switzerland)》2021,23(2)
The reduction of high-dimensional systems to effective models on a smaller set of variables is an essential task in many areas of science. For stochastic dynamics governed by diffusion processes, a general procedure to find effective equations is the conditioning approach. In this paper, we are interested in the spectrum of the generator of the resulting effective dynamics, and how it compares to the spectrum of the full generator. We prove a new relative error bound in terms of the eigenfunction approximation error for reversible systems. We also present numerical examples indicating that, if Kramers–Moyal (KM) type approximations are used to compute the spectrum of the reduced generator, it seems largely insensitive to the time window used for the KM estimators. We analyze the implications of these observations for systems driven by underdamped Langevin dynamics, and show how meaningful effective dynamics can be defined in this setting. 相似文献
109.
Proton acceleration using high-intensity laser pulses, at 1016 W/cm2 was studied irradiating different types of thin metal and plastic targets having 1-micron thickness. The maximization of the proton energy process was investigated optimizing the laser parameters, the irradiation conditions and the target properties. Employing 600–700 J laser pulse energy, a focalization inducing self-focusing effects and using targets with optimized thickness, it was possible to accelerate protons up to energies of above 8 MeV. The time-of-flight diagnostics has allowed to monitor the plasma properties and to control the ion acceleration process. 相似文献
110.
Copia Lorenzo Plastino Wolfango Nisi Stefano Ciarletti Marta Povinec Pavel P. 《Journal of Radioanalytical and Nuclear Chemistry》2017,311(1):385-393
Journal of Radioanalytical and Nuclear Chemistry - Groundwater samples, collected into the deep underground facilities of Gran Sasso National Laboratory of the National Institute of Nuclear Physics... 相似文献