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141.
R.J. Mcdonald A.J. Pacheco G.J. Wozniak H.H. Bolotin L.G. Moretto C. Schück S. Shih R.M. Diamond F.S. Stephens 《Nuclear Physics A》1982,373(1):54-80
Both the magnitude and alignment of the transferred angular momentum in the reaction 165Ho + 165Ho have been measured as a function of Q-value via continuum γ-ray multiplicity and anisotropy techniques. The spin transfer and the continuum γ-ray anisotropy increase throughout the quasi-elastic region. The spin transfer as a function of Q-value saturates at ~ 35?/fragment, the anisotropy peaks at a value of ~2 and then decreases to near unity for the largest Q-values. The observed anisotropies are in good agreement with predictions from an equilibrium statistical model in which thermal excitation of angular-momentum-bearing collective modes and neutron evaporation give rise to in-plane components of the angular momentum. 相似文献
142.
Ab initio SCF and CI calculations are reported which find the cyclic conformer of ozone to lie 16 kcal/mole above the preferred (open-chain) form of this substance. Polarization functions in the AO basis set are found to be quite important in this determination, strongly favoring the cyclic species. The possible experimental significance of such a relatively stable ring conformer of ozone is assessed. 相似文献
143.
144.
An unsaturated polyester resin and the styrene-crosslinked polyester were studied with laser Raman spectroscopy. Following the polyesterification reaction, Raman measurements showed that the polyester contained 55% fumarate and 45% maleate unsaturation. Additionally, the glycol fragment was indicated to exist as the gauche isomer. The 1213 cm?1 line is assigned to the glycol-ester linkage and can be measured to follow the conversion to polymer. After the crosslinking reaction, styrene was found to copolymerize preferentially with the fumarate unsaturation. There was no evidence of forming long-chain polystyrene crosslinks. Our results indicate that, after crosslinking, 41% of the fumarates have reacted with styrene and there is an average of two styrene molecules in each link. 相似文献
145.
146.
By using scanning tunneling spectroscopy to probe a silver thin film that contains both periodic and quasiperiodic modulation, and by using Fourier analysis, we unravel the influences of individual Fourier components of the scattering potential (periodic versus quasiperiodic) on the electronic structure of a one-dimensional quasiperiodically modulated thin Ag film. Along the periodically modulated direction, a Bragg reflection-induced energy gap is observed in k space. On the other hand, the exotic E vs k spectrum with many minigaps was observed along the quasiperiodic direction. 相似文献
147.
Can two-photon correlation of chaotic light be considered as correlation of intensity fluctuations? 总被引:2,自引:0,他引:2
Two-photon correlation phenomena, including the historical experiment of Hanbury Brown and Twiss, may have to be described quantum mechanically, regardless of whether the source of radiation is classical or quantum. Supporting this point, we present a ghost imaging type of second-order spatial correlation experiment of chaotic light to show that the classical understanding based on the concept of statistical intensity fluctuations does not give a correct interpretation for the observation. From a practical point of view, this experiment demonstrates the possibility of having high contrast lensless two-photon imaging with chaotic light, suggesting imaging applications for radiations for which no effective lens is available. 相似文献
148.
Shih PI Chiang CL Dixit AK Chen CK Yuan MC Lee RY Chen CT Diau EW Shu CF 《Organic letters》2006,8(13):2799-2802
[reaction: see text] A series of carbazole/fluorene (CBZm-Fn) hybrids were effectively synthesized through Friedel-Crafts-type substitution of the carbazole rings. These compounds were thermally and morphologically stable host materials for OLED applications. Efficient blue phosphorescent OLEDs were obtained when employing CBZ1-F2 as the host and FIrpic as the guest. 相似文献
149.
Cheng-Hung Shih Wen-Yuan Pang Chia-Ho Hiseh 《Journal of Physics and Chemistry of Solids》2010,71(12):1664-1668
We have studied the microstructure property of InN epitaxial films grown on ZnO substrate by plasma-assisted molecular beam epitaxy. We found that the In2O3 compound was produced on ZnO substrate and many pits were formed on the InN films when InN was directly grown on ZnO substrate with the N/In flux ratio less than 40. We demonstrated that the quality of InN film was significantly improved when the In2O3 layer was used as a buffer to prevent the reaction between In and the ZnO substrate. 相似文献
150.
Wan Kuang Alex English Min-Hsiung Shih Jeunghoon Lee Bernard Yurke 《Optics Communications》2010,283(20):4090-24053
The transmission property of metallic films with two-dimensional hole arrays is studied experimentally and numerically. For a triangular lattice subwavelength hole array in a 150 nm thick Ag film, both cavity resonance and planar surface modes are identified as the sources of enhanced optical transmissions. Semi-analytical models are developed for calculating the dispersion relation of the cavity resonant mode. They agree well with the experimental results and full-wave numerical calculations. Strong interaction between the cavity resonant mode and surface modes is also observed. 相似文献