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121.
122.
The European Union is creating strict standards for air and water pollution and waste treatment and implementing aggressive regulations. Compliance with these regulations is impossible without the development of new depollution processes involving plasma or laser technology. Time is one of the major problems in monitoring pollutants with the use of the time-resolution laser-induced breakdown spectroscopy technique, which can perform online analysis without sampling with a high level sensitivity for all the species of the Periodic Table. Plasma-enhanced desorption from fly ashes or polluted soils associated with a mass spectrometer or an optical emission spectrometer allows the monitoring of volatile organic compounds (VOCs) and organochlorine species in a few seconds. In the last DBD point, we present the treatment of VOCs in air by the plasma technique in order to destroy or trap PAH molecules.  相似文献   
123.
Two different synthetic routes to 5-(3,6-dihydro-2-oxo-2H-1,3,4-thiadiazin-5-yl)-1H-indole-2,3-diones are described. The reaction sequences represent a facile entry into these series of isatin derivatives.  相似文献   
124.
Novel procedures for the determination of florfenicol in freshwater, sediments and bryophyte Fontinalis antipyretica, using reversed-phase high-performance liquid chromatography are described. Liquid chromatography was performed on a 5 µm PuroSpher RP-18E® column using methanol and 0.05 M phosphate buffer (18/82 v/v, pH 7.3) as mobile phase (0.8 ml min?1) and fluorescence detection (excitation wavelength 265 nm and emission wavelength 295 nm). Florfenicol was determined in centrifuged freshwater samples. Florfenicol was extracted from sediments and bryophytes samples by using a solid-liquid extraction step followed by a solid phase extraction step. Linearity was confirmed over the concentration range 25–1000 ng mL?1 water and 50-1000 ng g?1 sediment or bryophyte. Limits of detection and quantitation were 8 and 25 ng mL?1 water and 17 and 50 ng g?1 sediment or bryophyte respectively. Mean extraction recoveries of florfenicol from sediments and bryophyte were from 85.9 to 109.1%.  相似文献   
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Recent developments in meshless numerical methods have led to algorithms that can be used to solve arbitrarily large problems without the support of a connected mesh, and without the computational cost and numerical ill-conditioning issues usually associated with such solution techniques. This work applies the Local Hermitian Interpolation (LHI) method, based on local interpolation with Radial Basis Functions (RBFs), to the solution of 3D unsaturated porous media problems. The proposed implementation is capable of handling real soil properties, provided either as an analytical function or as a series of pointwise measurements. The technique is implemented with implicit and explicit timestepping, and is validated against two transient Richards’ equation models, of which one has a known analytical solution. In addition, a real-world infiltration problem based on a saturated–unsaturated formulation is modelled, using a realistic variation of soil properties with water-pressure.  相似文献   
127.
A method for carrying out strain partition under load is described. An ultrasonic device and a suitable extensometer are used simultaneously. Applied to a ceramic matrix composite, it allows one to evaluate the contribution of the various damage mechanisms on its highly nonlinear behavior.  相似文献   
128.
Equality between the interval dimensions of a poset and its MacNeille completion, announced in [7], has been obtained by the authors as a byproduct of their study of Galois lattices in [8]. The purpose of this note is to give a direct proof, similar to the classical proof of Baker's result stating that the dimension (in the Dushnik-Miller sense) of a poset and its MacNeille completion are the same.Supported by French PRC Math-Info.  相似文献   
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Aromatic side chains are important reporters of the plasticity of proteins, and often form important contacts in protein–protein interactions. We studied aromatic residues in the two structurally homologous cross-β amyloid fibrils HET-s, and HELLF by employing a specific isotope-labeling approach and magic-angle-spinning NMR. The dynamic behavior of the aromatic residues Phe and Tyr indicates that the hydrophobic amyloid core is rigid, without any sign of “breathing motions” over hundreds of milliseconds at least. Aromatic residues exposed at the fibril surface have a rigid ring axis but undergo ring flips on a variety of time scales from nanoseconds to microseconds. Our approach provides direct insight into hydrophobic-core motions, enabling a better evaluation of the conformational heterogeneity generated from an NMR structural ensemble of such amyloid cross-β architecture.  相似文献   
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