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排序方式: 共有73条查询结果,搜索用时 31 毫秒
1.
Ulenikov O. N. Tolchenov R. N. Melekhina E. N. Koivusaari M. Alanko S. Anttila R. 《Journal of Molecular Spectroscopy》1995,170(2)
High resolution Fourier transform spectra of deuterated hydrogen sulfide have been recorded in the region 2400-3000 cm−1. Rotational structures of the ν1 + ν2, ν2 + ν3 bands of D232S, of the ν3 and ν1 + ν2 bands of HD32S, and of the ν1 + ν2 band of HD34S were analyzed. Band centers and rotational, centrifugal distortion, and resonance parameters were obtained, which reproduce the initial values of the upper energy levels within a mean accuracy of 1.39 × 10−4 cm−1 for the states (110) and (011) of D232S, 1.61 × 10−4 cm−1 and 1.82 × 10−4 cm−1 for the states (001) and (110) of HD32S, and 2.09 × 10−4 cm−1 for the state (110) of HD34S, respectively. 相似文献
2.
Milla Anttila Keith Ball Irini Perissinaki 《Transactions of the American Mathematical Society》2003,355(12):4723-4735
It is shown that every symmetric convex body which satisfies a kind of weak law of large numbers has the property that almost all its marginal distributions are approximately Gaussian. Several quite broad classes of bodies are shown to satisfy the condition.
3.
In the literature one basic work can be found that describes an attempt to verify the applicability of the orthotropic plate wave theory to paper. In the present study we have repeated the key experiment and also modified the original experimental set-up to be able to make new complementary measurements. The performed verification attempt is based on a key experiment in which an ultrasonic resonance method is used. When it is applied to paper, a second resonance can be observed in addition to the one that originates from the asymmetric A0 mode. The result of the verification experiment is conclusive only if the source of this second resonance is the symmetric S0 mode. Our results show that the second resonance is not generated by the S0 mode. Instead, they indicate that the source is a longitudinal wave propagating in the thickness direction of the paper. We therefore conclude that the applicability of the orthotropic plate wave theory to paper cannot be verified by performing the key experiment that is described in the literature. 相似文献
4.
For a systematic prediction of the radiation-enhanced outdiffusion occurring during implantation, the use of a model based
on the effect of vacancy flow on diffusion is described. The model agrees reasonably well with experiments in all twentysix
measured cases. For the systematic understanding of the radiation enhanced outdiffusion, an approximative diagram based on
the activation energy of self-diffusion is constructed for all pure elements and its application possibilities are discussed. 相似文献
5.
6.
The infrared spectrum in the range 900-1230 cm(-1) including the fundamental bands nu(3) and nu(6) of CD(3)CN has been studied. The resolution attained was 0.0025 cm(-1) in the measurement on the Bruker 120 HR Fourier spectrometer in Oulu. About 4000 lines were assigned in the nu(6) band. For the weak nu(3) band, which has not been observed earlier directly, we were able to assign 206 lines in three subbands K=8-10. These lines become detectable due to the strong nu(3)/nu(6) Coriolis resonance. There is also an l(1,-2) resonance between nu(3) and nu(6), which made it possible to obtain a value 2.647721(50) cm(-1) for the axial rotational constant A(0), when D(0)(K) from force field calculations was applied. Different types of resonances with the overtone 3nu(8) and the combinations nu(4)+nu(8) and nu(7)+nu(8) were observed. A fit with a standard deviation of 0.0019 cm(-1) was attained by using a model of 10 different resonances. Copyright 2001 Academic Press. 相似文献
7.
The spline collocation method for a class of biperiodic strongly elliptic pseudodifferential operators is considered. As trial
functions tensor products of odd degree splines are used and the collocation is imposed at the nodal points of the tensor
product mesh. It is shown that the collocation problem is uniquely solvable if the maximum mesh length is small enough. Moreover,
the approximation is stable and quasioptimal with respect to a norm depending on the order of the operator and the degree
of approximating splines. Some convergence results are given for general and quasiuniform meshes. The results cover for example
the single layer and the hypersingular operators. 相似文献
8.
Oleg N. Ulenikov Eizi Hirota Mitsuru Akiyama S. Alanko M. Koivusaari R. Anttila G. Guelachvili R. N. Tolchenov 《Journal of Molecular Spectroscopy》1996,180(2):423-432
The infrared spectrum of doubly deuterated methane CH2D2has been recorded in the region from 1900 to 2400 cm−1at almost Doppler-limited resolution by using two high-resolution Fourier transform spectrometers. The vibrational bands observed include 2ν4, ν4+ ν7, 2ν7, ν2, ν8, ν4+ ν9, and ν7+ ν9, which were analyzed by taking into account Coriolis and Fermi interactions among them and also those with ν4+ ν5, ν3+ ν7, and ν5+ ν7. Most of the centrifugal distortion constants were constrained to appropriate values, while the vibrational term value and three rotational constants in each of the seven excited states were adjusted along with Coriolis and Fermi interaction parameters by the least-squares analysis of the observed spectrum. The vibration–rotation interaction constants αsthus determined for the ν2and ν8states were combined with those of other fundamental states already published to calculate the equilibrium C–H distance. 相似文献
9.
The diffusion coefficients of nitrogen in N-implanted polycrystalline Ni have been deduced. Both bulk and Ni-evaporated samples implanted with nitrogen were annealed at 150–500° C. The nitrogen profiles were probed using the nuclear resonance broadening technique. The value of 0.99±0.12 eV for the activation energy and (3.0
–2.8
+40
)×10–6 cm2/s for the frequency factor were obtained for implanted N in bulk Ni. The solubilities for both the bulk and evaporated Ni samples are given. In evaporated Ni nitrogen migration is enhanced due to the defects arising during evaporation. 相似文献
10.
The infrared band ν4 of CD3I between 2220 and 2390 cm?1 has been investigated at a resolution of 5.4 × 10?3 cm?1. More than 2000 lines were assigned to subbands with KΔK from ?18 to 21, including J values up to 70. In the analysis the Coriolis resonances with ν3 + ν5±1 + ν6±1, ν2 + 2ν6±2, ν2 + 2ν60, and 2ν3 + 2ν6±2 were taken into account. The molecular constants concerning the fundamental ν4, as well as the parameters describing the combination levels, were derived. 相似文献