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121.
We give an elementary theory of Henselian local rings and construct the Henselisation of a local ring. All our theorems have an algorithmic content. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
122.
123.
Henri Imbert A. Astruc und Schon früher 《Fresenius' Journal of Analytical Chemistry》1901,40(2):127-129
Ohne Zusammenfassung 相似文献
124.
125.
Ohne Zusammenfassung 相似文献
126.
Henri Lasne 《Fresenius' Journal of Analytical Chemistry》1889,28(1):348-350
Ohne Zusammenfassung 相似文献
127.
Takashi Tsuno Yu Sugiyama Henri Brunner Michael Bodensteiner Kosei Lee 《Journal of Coordination Chemistry》2017,70(20):3459-3470
Treatment of NiCl2 with the tripod ligand (LMent,SC)-1H led to (LMent,SC)-[Cp(PNMent)NiCl] in which the potentially tridentate ligand coordinated to the metal center in a bidentate way via the cyclopentadienyl system and the phosphorus atom. In the presence of NH4PF6 [(LMent,SC)-[Cp(PNMent)NiCl] readily underwent Cl/PPh3 exchange to give (LMent,SC)-[Cp(PNMent)NiPPh3]PF6. Reaction of (LMent,SC)-[Cp(PNMent)NiCl] with 0.5 eq. of dppe afforded [{(LMent,SC)-[Cp(PNMent)Ni]}2dppe](PF6)2. (LMent,SC)-[Cp(PNMent)NiPPh3]PF6 and [{(LMent,SC)-[Cp(PNMent)Ni]}2dppe](PF6)2 were characterized by NMR and MS spectroscopy, and also by single crystal X-ray diffraction. The cyclopentadienyl ligand of (LMent,SC)-[Cp(PNMent)NiPPh3]PF6 shows a distortion intermediate between the ene-allyl and diene types, while the two cyclopentadienyl ligands of [{(LMent,SC)-[Cp(PNMent)Ni]}2dppe](PF6)2 have intermediate and diene distortions, respectively. According to the temperature dependent NMR spectra of (LMent,SC)-[Cp(PNMent)NiPPh3]PF6 and [{(LMent,SC)-[Cp(PNMent)Ni]}2dppe](PF6)2 two different conformations of the tether in the Cp(PNMent)Ni system could be frozen out at low temperatures. 相似文献
128.
Daniel Desbordes Henri Noël Presles Franckie Joubert Cresus Gbagdo Douala 《Comptes Rendus Mecanique》2004,332(12):993-999
Calculations of the detonation reaction zone of gaseous H2NO2/N2O4 mixtures in the range of equivalence ratio Φ between 0.25 and 0.7 show that for 0.25Φ0.4 the chemical energy is released in two distinct and successive exothermic steps characterised by different chemical characteristic times. As for rich mixtures, the first exothermic step is mainly due to the reaction NO2 + H → NO + OH, but the second one is different since it results from the exothermic decomposition of NO into N2 and O2. For Φ=0.3 the measured detonation velocity in a tube of 52 mm internal diameter is very much smaller than the calculated value and the mean size of the cellular structure is very much larger than the value extrapolated from data obtained with mixtures of higher but close equivalence ratio. All these results show that the detonation, though self-sustained and steady, is ‘non-ideal’, i.e. it is supported only by a part of the available chemical energy, that provided mainly by the first exothermic step. To cite this article: D. Desbordes et al., C. R. Mecanique 332 (2004). 相似文献
129.
The ozonation of four bornene derivatives, prepared from (R)-(+)-pulegone, which possess a particularly hindered double bond, led to the formation of unexpected products depending on the nature of the solvent. The formation of the corresponding epoxides, ketones with the same skeleton, various lactones and even an allyl alcohol and an allyl chloride (allylic functionalisation) was observed. In two cases, products presenting a pulegone modified skeleton resulting from a Wagner-Meerwein rearrangement were obtained. The structure of three products was confirmed by crystallographic X-ray analysis. Mechanisms taking into account the rigid and congested structure of the reactants explain these results. The most striking steps were backed up by theoretical calculations. 相似文献
130.
Véronique Raverot Jonathan Lopez Catherine Grenot Henri Déchaud 《Analytica chimica acta》2010,658(1):87-9857
Testosterone (T) circulates in the blood tightly bound to sex hormone-binding globulin (SHBG) and weakly to albumin. Measuring protein unbound T (free) or non-SHBG-bound T rather than total T has been recommended for the evaluation of androgen disorders in humans. Ammonium sulfate precipitation has been widely used to separate [SHBG-T] complex from free and albumin-bound T. To achieve more specificity in this separation, we used monoclonal anti-SHBG antibody and developed a suitable and convenient immunoassay for measuring non-SHBG-bound T. Magnetic beads were covalently coupled to a monoclonal anti-SHBG antibody to capture [SHBG-T] complex from plasma samples. Magnetic separation was then performed to allow measurement of non-SHBG-bound T in the supernatant by direct radioimmunoassay. When 300 μL of plasma samples were incubated at room temperature with 10 μL of anti-SHBG beads, residual SHBG concentration was undetectable in the supernatant. The specificity of proteins retained on anti-SHBG beads was further demonstrated by peptide mass fingerprint on a MALDI-TOF analyzer. The non-specific adsorption of T on beads was low (5%), and dissociation of T from SHBG-T complex was less than 5% after 180 min of incubation. The plasma concentrations of non-SHBG-bound T using anti-SHBG beads were highly correlated to those obtained using ammonium sulfate precipitation. We conclude that SHBG immunocapture is a highly specific and useful tool for an experimental direct measurement of plasma non-SHBG-bound T. This methodology is also convenient and appropriate for routine and automated assay. 相似文献