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101.
Marie-Claire Lasne Jean-Louis Ripoll Jean-Claude Guillemin Jean-Marc Denis 《Tetrahedron letters》1984,25(35):3847-3848
5,6-dihydropyridine 1 is synthesized either by flash vacuum thermolysis of 1-azabicyclo[2.2.2] oct-2-ene 3 or by dehydrochlorination over solid bases of N-chloro-1,2,5,6-tetrahydropyridine 4 and characterized at low temperature by its 1H and 13C nmr and ir spectra. 相似文献
102.
Aldée Cabana Yves Doucet Jean-Marc Garneau Claude Pépin Pascal Puget 《Journal of Molecular Spectroscopy》1982,96(2):342-350
The vibration-rotation bands 2ν1, 2ν3, ν1 + ν2, ν2 + ν3, and ν1 - ν2 of H12CP were recorded and analyzed. These data were combined with previously reported results for this molecule to obtain an improved and extended set of vibrational and rotational constants. All xij and γij were calculated except those that require data from a summation band involving ν1 and ν3. 相似文献
103.
Jean-Marc Rousseau Gilbert Laporte 《The Journal of the Operational Research Society》1977,28(1):33-35
A scheduling problem in an outpatient clinic is considered. First the system is represented by means of a simple queueing model. The problem of minimising the patients' total queueing time is then formulated as a non-linear program and solved by applying the Kuhn-Tucker conditions. The results obtained enable the person who manages the appointment system to allocate appointment dates to patients who have different priorities. 相似文献
104.
Burke CS McGaughey O Sabattié JM Barry H McEvoy AK McDonagh C MacCraith BD 《The Analyst》2005,130(1):41-45
This paper describes the development of a generic platform for enhanced, integrated optic sensors based on fluorescence detection. The platform employs a novel optical configuration in order to achieve enhanced performance and has inherent multianalyte detection capability. The sensor element comprises a multimode ridge waveguide that has been patterned with an analyte-sensitive fluorescent spot, which is excited directly using a LED. The platform was applied to the detection of gaseous oxygen as a proof of principle. The sol-gel-derived sensor spots were doped with an oxygen-sensitive fluorescent dichlororuthenium dye complex and intensity-based calibration data were generated from the oxygen-dependent waveguide output. The sensor achieved a LOD of 0.62% and a resolution of less than 0.96% gaseous oxygen, which compares favourably with a similar, recently reported system. This device highlights the combination of inexpensive rapid prototyping techniques and a dedicated sensor enhancement strategy that together facilitate the production of an effective prototype sensor platform. 相似文献
105.
106.
The vibration-rotation bands ν2, 2ν2, and several “hot” bands of H12CP have been recorded and assigned. The states with v2 = 2, perturbed by l-type resonance and l-type doubling effects have been analyzed on the basis of the existing theory. The energy difference between the 0220 and the 0200 states was found to be 17.5095 (19) cm?1. Because of insufficient data, the states with v2 = 3 could not be corrected for l-type resonance interaction and therefore only an effective l-type doubling constant was obtained. The ν1 and ν2 bands of the H13CP isotopic molecule (present at natural concentration) were also identified and their spectroscopic constants obtained. The value of Ie for H12CP is found to be 25.18793 (26) amu Å2. 相似文献
107.
Jean Bellissard Riccardo Benedetti Jean-Marc Gambaudo 《Communications in Mathematical Physics》2006,261(1):1-41
The continuous Hull of a repetitive tiling T in ℝd with the Finite Pattern Condition (FPC) inherits a minimal ℝd-lamination structure with flat leaves and a transversal which is a Cantor set. This class of tiling includes the Penrose & the Amman Benkker ones in 2D, as well as the icosahedral tilings in 3D. We show that the continuous Hull, with its canonical ℝd-action, can be seen as the projective limit of a suitable sequence of branched, oriented and flat compact d-manifolds. As a consequence, the longitudinal cohomology and the K-theory of the corresponding C*-algebra are obtained as direct limits of cohomology and K-theory of ordinary manifolds. Moreover, the space of invariant finite positive measures can be identified with a cone in
the dth homology group canonically associated with the orientation of ℝd. At last, the gap labeling theorem holds: given an invariant ergodic probability measure μ on the Hull the corresponding Integrated Density of States (IDS) of any selfadjoint operators affiliated to takes on values on spectral gaps in the ℤ-module generated by the occurrence probabilities of finite patches in the tiling.
Accepted in Revised Form: 7 May 2005 相似文献
108.
Sorption thermodynamics of CO2, CH4, and their mixtures in the ITQ-1 zeolite as revealed by molecular simulations 总被引:1,自引:0,他引:1
Leyssale JM Papadopoulos GK Theodorou DN 《The journal of physical chemistry. B》2006,110(45):22742-22753
The thermodynamic properties and siting of carbon dioxide and methane sorbed in the siliceous form of zeolite MCM-22, ITQ-1, were studied by means of grand canonical Monte Carlo simulation. ITQ-1 comprises two independent pore systems of different geometry. It was found to be CO(2)-selective toward CO(2)/CH(4) gas mixtures, its equilibrium selectivity being distinctly higher in its sinusoidal channel pore system than in the large cavity system over a wide range of pressures starting from the Henry law regime, at the three temperatures considered. A maximum in selectivity is observed at low temperature, high pressure, and methane-rich gas-phase composition. 相似文献
109.
Fontaine-Gautrelet C Krafft JM Djéga-Mariadassou G Thomas C 《The journal of physical chemistry. B》2006,110(20):10075-10081
The low-temperature adsorption of N(2) on Rh/SiO(2) samples of various particle-size distributions was followed by FTIR. The addition of O(2) pulses on Rh(0) surfaces saturated with chemisorbed N(2) allowed us to reassign stretching frequencies attributed originally to N(2)-Rh(0) to N(2)-Rh(delta+). The formation of the latter oxidized Rh species is assumed to be induced by an electron withdrawal from adsorbed oxygen species on Rh surface centers neighboring those onto which N(2) species are chemisorbed. The present work, thus, enables us to delimit ranges of frequencies for which the adsorption of N(2) can be considered to occur on either Rh(0) or Rh(delta+) centers for nu(N2) lower or higher than 2243 cm(-1), respectively. The N(2)-FTIR experiments performed on the studied catalysts also suggest a lattice plane selectivity for N(2) adsorption on metallic Rh planes of different natures which, to our knowledge, has not been reported yet for Rh. 相似文献
110.