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101.
A general method for estimating E(exp(iNΦ)) for N → + ∞ is given using a stationary phase method in Wiener space and stochastic variational calculus. 相似文献
102.
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
103.
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
104.
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
105.
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
106.
107.
The infrared spectra of simple nonsubstituted-diketones have been analyzed; this makes it possible to obtain information on their keto-enol equilibria. The ease of enolization of these-diketones changes considerably when a cyclic structure is formed, and depends on the dimensions of the ring. The nature of the enol bands in the infrared spectra is discussed. 相似文献
108.
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
109.
Juha?M.?Saarela Torbj?rn?L?fqvist Kerstin?Ramser Per?Gren Erik?Olson Jan?Niemi Mikael?Sj?dahl 《Central European Journal of Physics》2010,8(2):235-241
This study is focused on exploring the feasibility of an all-optic surface scanning method in determining the size and position
of a submerged, laser generated, optoacoustic (OA) source. The optoacoustic effect in this case was generated when the absorption
of a short electromagnetic pulse in matter caused a dielectric breakdown, a plasma emission flash and a subsequent acoustic
wave. In the experiment, a laser pulse with λ = 1064 nm and 12 ns pulse length was aimed at a volume of deionized water. When
the laser beam was focused by a f = 16 mm lens, a single dielectric breakdown spot occurred. When a f = 40 mm was used several breakdowns in a row were induced. The breakdowns were photographed using a double shutter camera.
The acoustic wave generated by the dielectric breakdowns were detected at a point on the water surface using a laser Doppler
vibrometer (LDV). First, the LDV signal was used to calculate the speed of sound with an accuracy of 10 m/s. Secondly, the
location and length of the dielectric breakdown was calculated with an accuracy of 1 mm. The calculated position matched the
breakdown location recorded by a camera. The results show that it is possible to use LDV surface measurements from a single
spot to determine both the position and length of the OA source as well as the speed of sound in the medium. Furthermore,
the LDV measurements also show a secondary peak that originates from the OA source. To unravel the origin and properties of
this interesting feature, further investigations are necessary 相似文献
110.
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