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The mass spectra of α-, β- and γ-pyridine aldoximes and the respective O-methyl ethers were studied. The mass spectral behaviour of α-pyridine aldoxime is characterized by the elimination of NO, while the molecular ion of the γ-isomer expels H2 CN. In the case of the β-isomer the formation of the m/e 67 ion (C4H5N) in a concerted process is the main feature. In the α-pyridine aldoxime methyl ether, in sharp contrast to the hydroxy analog, the M-30 peak was found to be due to the elimination of CH2O, the expulsion of NO being absent. The mechanism of the fragmentation reactions is discussed, the conclusion drawn being based on the high resolution measurements as well as on the spectra of the respective deuterioanalogs and on the metastable transitions.  相似文献   
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A method is presented for the heterometric determination of 0.2–0.5 mg ferric iron with aluminon. The analysed solution may contain excesses of coloured or colourless foreign bi-or trivalent Cations. The latter may make up ? 99.5% of the total metal content. The working conditions were studied. The determination lasts 10–15 minutes and the error is 0–2%.  相似文献   
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Traces of ferric iron were determined heterometrically in concentrated solutions of potassium thiocyanate by titration with nitron. The solutions could contain 99.9% of the following cations: Ca+2, Ba+2, Mg+2, Zn+2, Cr+3, Al+3, Mn+2. Cd+2, Th+4, Ce+3 or 99% of Ni+2, Pb+2, Cu+2, Mo+6, v+5 and W. A titration usually lasted 5 min and in most cases the error was ca. 1%. The molar ratio of [Fe] : [nitron] was always equal to 1 : 6.6.  相似文献   
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In this article, we derive the intrinsic equations for a generalized relaxed elastic line on an oriented surface in the Galilean 3-dimensional space G3. These equations will give direct and more geometric approach to questions concerning about generalized relaxed elastic lines on an oriented surface in G3.  相似文献   
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Background  

In the adult hippocampus, the granule cell layer of the dentate gyrus is a heterogeneous structure formed by neurons of different ages, morphologies and electrophysiological properties. Retroviral vectors have been extensively used to transduce cells of the granule cell layer and study their inherent properties in an intact brain environment. In addition, lentivirus-based vectors have been used to deliver transgenes to replicative and non-replicative cells as well, such as post mitotic neurons of the CNS. However, only few studies have been dedicated to address the applicability of these widespread used vectors to hippocampal cells in vivo. Therefore, the aim of this study was to extensively characterize the cell types that are effectively transduced in vivo by VSVg-pseudotyped lentivirus-based vectors in the hippocampus dentate gyrus.  相似文献   
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