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41.
42.
Jacques Dubac Pierre Mazerolles Monique Joly 《Journal of organometallic chemistry》1977,128(2):C18-C20
Stereospecific synthesis of geometric isomers of 1,2-dimethyl-1-phenylsilacyclopentane is described. We demonstrate that brominolysis of the arylsilicon bond occurs with predominant inversion of configuration at the silicon atom of the silacyclopentane ring. 相似文献
43.
Jacques Dubac Pierre Mazerolles Monique Joly 《Journal of organometallic chemistry》1977,128(2):C21-C24
The stereoselective alcoholysis of 1,2-dimethyl-1-chlorosilacyclopentane and the catalytic alcoholysis of 1,2-dimethylsilacyclopentane are described. 相似文献
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46.
Ground-state Al atoms have been reacted with cyclopropylamine (CpNH2) in an adamantane matrix at 77 K. The four paramagnetic species generated in the reaction have been studied by electron paramagnetic resonance (EPR) spectroscopy and their magnetic parameters extracted from the EPR spectra. The isotropic Al hyperfine interactions (hfis) for these radicals vary from 801 to 962 MHz and are consistent with values previously reported for structurally similar Al-centered radicals. The major species formed in the reaction has a highly anisotropic a tensor indicative of an Al-centered radical with a substantial amount of the unpaired spin density residing in the Al 3p orbital. In addition, there is EPR evidence that the insertion products, CpNH(AlH) and CpAlNH2, are formed in the reaction, suggesting that Al atoms can activate the N-H and C-N bonds of amines. It has been shown that a molecule of CpNH2 coordinates to CpNH(AlH), causing the Al, N and H hfi of the N-H insertion product to decrease. The values of the nuclear hfis calculated for the insertion products, using a density functional theory (DFT) method, are comparable to the experimental values. 相似文献
47.
G. Durry J. S. Li I. Vinogradov A. Titov L. Joly J. Cousin T. Decarpenterie N. Amarouche X. Liu B. Parvitte O. Korablev M. Gerasimov V. Zéninari 《Applied physics. B, Lasers and optics》2010,99(1-2):339-351
A near-infrared tunable diode laser spectrometer called TDLAS has been developed that combines telecommunication-type as well as new-generation antimonide laser diodes to measure C2H2, H2O, CO2 and their isotopologues in the near infrared. This sensor is devoted to the in situ analysis of the soil of the Martian satellite PHOBOS, within the framework of the Russian space mission PHOBOS-GRUNT. In the first part of the paper, we report accurate spectroscopic measurements of C2H2 and 13C12CH2 near 1.533 μm, of H2O and CO2 at 2.682 μm and of the isotopologues 13C16O2 and 16O12C18O near 2.041 μm and H2 17O, H2 18O and HDO near 2.642 μm. The achieved line strengths are thoroughly compared to data from molecular databases or from former experimental determinations. In the second part of the paper, we describe the TDLAS spectrometer for the PHOBOS-GRUNT mission. 相似文献
48.
Joly AG Henyk M Beck KM Trevisanutto PE Sushko PV Hess WP Shluger AL 《The journal of physical chemistry. B》2006,110(37):18093-18096
Ultraviolet excitation of high surface area MgO films using 4.7 eV femtosecond pulses results in neutral Mg-atom desorption with hyperthermal kinetic energies in the range 0.1-0.4 eV. The Mg-atom hyperthermal energies and power dependences are similar to those previously observed using nanosecond pulsed excitation. Femtosecond two-pulse correlation measurements reveal the existence of different dynamical paths for Mg-atom desorption. One mechanism displays a sub-150 fs time scale and involves the simultaneous or near-simultaneous transition of two electrons to a 3-coordinated Mg(2+) site. Other paths display picosecond time scales that we associate with dynamics following electron trapping at 3-coordinated Mg(2+) surface sites. 相似文献
49.
Joly KM Wilson C Blake AJ Tucker JH Moody CJ 《Chemical communications (Cambridge, England)》2008,(41):5191-5193
Planar chirality associated with the ferrocene in ferrocenyl oximes and hydrazones bearing chiral auxiliaries effectively competes with or overrides the normally excellent stereocontrol afforded by the auxiliary in determining the diastereoselectivity of addition to the C=N bond. 相似文献
50.
Quantitative analysis of the fluorescence induction (FI) rise was used in this study to elucidate the complex effects of N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD) on thylakoids. Reduced TMPD molecules, responsible for the ADRY agent effect, caused an increase in the amplitude of the O-J rise. Also, only oxidized TMPD molecules were shown to have the ability to bind the Q(B) pocket of photosystem II (PSII). On the other hand, the I-P rise was slowed in proportion with the oxidized TMPD concentration, inducing the clear appearance of the I-peak. While this property was previously thought to be unique to TMPD, this study shows that some artificial electron acceptors of PSII, silicomolybdate, 2,5-dichloro-p-benzoquinone, and phenyl-p-benzoquinone, have a similar effect. These results demonstrated a major role of the oxido-reduction kinetics of the PQ-pool in the resolution of J-I and I-P phases in the FI of isolated thylakoids. 相似文献