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161.
In this paper we prove a Strassen version of the law of the iterated logarithm for some sequences of weakly asymptotically independant Banach space valued gaussian random variables which converge in distribution, and we prove that the central limit theorem implies the functional form of the law of the iterated logarithm for the partial sums of certain Banach space valued gaussian sequences.Furthermore we give conditions for the convergence in distribution of sequences of gaussian random variables and gaussian stochastic processes, and these conditions permit us to prove that our results generalize in the gaussian case all similar results known to the authors at present.  相似文献   
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New generation of sequential injection analysis (SIA) called sequential injection chromatography (SIC) has already been consolidated as a good alternative of high performance liquid chromatography (HPLC) for fast analysis of simple samples. Benefits of flow methods are automation, miniaturization and low sample and mobile phase consumption. Implementation of short monolithic chromatographic column into SIA opens new area—on-line chromatographic separation of multi-compound sample in low-pressure flow system, with the advantage of flow programming and possibility of sample manipulation. In the presented review the potential of SIC and its comparison with HPLC for determination of pharmaceutical mixtures is discussed and outlines past and recent trends focused on separation with SIC.  相似文献   
165.
Abstract

Changes of specific rotation of protein irradiated with Co-60 gamma-rays were restored by some amino acids, such as mono-sodium 1-glutamate. Loss of this recovery effect in some amino acids by irradiation was studied by polarimetry and infrared spectometry. Optical rotation of protein-amino acid solutions increased with an increasing radiation dose given to the amino acids. Changes in optical rotation with irradiation may be due to the loss of the recovery effect of amino acids for the irradiated protein molecule. Changes in infrared spectra increased with an increasing radiation dose given to the amino acids. Such changes in infrared spectra with irradiation may be due to destruction of some radicals in the amino acid molecule.  相似文献   
166.
We study a system of microdifferential (=pseudodifferential) equations. We assume that the characteristic varietyV of takes the formV=V 1V2; hereV 1andV 2are regular involutory submanifolds and intersect normally, andV 1V2is non-involutory and 1-codimensional both inV 1and inV 2. We also assume that has regular singularities alongV. Then we give a canonical form of in the complex domain. This enables us to investigate the branching of supports of microfunction solutions of when is hyperbolic.  相似文献   
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We report the preliminary results of our experiments with stimulated Raman scattering in para-hydrogen crystal aimed at developing a continuously tunable laboratory laser source of mid-infrared radiation. With laser pulses at 532 nm, a conversion efficiency for the first Stokes beam of as much as 20% in the forward direction was observed through a single-pass, 5-cm-long crystal. Generation of mid-infrared pulses at 4.5 microm was achieved by use of the output of a near-infrared pulsed laser (1.6 microm, 3 ns), and an absorption spectrum of gaseous CD4 molecules was successfully recorded. These results suggest use of the solid para-hydrogen Raman shifter as a promising light source for mid-infrared spectroscopy.  相似文献   
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A new separation method based on a novel reversed-phase sequential injection chromatography (SIC) technique was used for simultaneous determination of ambroxol hydrochloride and doxycycline in pharmaceutical preparations in this contribution.The coupling of short monolith with SIA system results in an implementation of separation step to until no-separation low-pressure method.A Chromolith® Flash RP-18e, 25-4.6 mm column (Merck, Germany) and a FIAlab® 3000 system (USA) with a six-port selection valve and 5 ml syringe were used for sequential injection chromatographic separations in our study. The mobile phase used was acetonitrile-water (20:90, v/v), pH 2.5 adjusted with 98% phosphoric acid, flow rate 0.48 ml min−1, UV detection was at 213 nm.The validation parameters have shown good results: linearity of determination for both compounds including internal standard (ethylparaben) >0.999; repeatability of determination (R.S.D.) in the range 0.5-5.4% at three different concentration levels, detection limits in the range 0.5-2.0 μg ml−1, and recovery from the pharmaceutical preparation in the range 99.3-99.9%. The chromatographic resolution between peak compounds was >5.0 and analysis time was <9 min under the optimal conditions. The method was found to be applicable for routine analysis of the active compounds ambroxol hydrochloride and doxycycline in various pharmaceutical preparations.  相似文献   
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