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51.
A simple method is proposed which allows obtaining distributed-feedback laser action simultaneously at several spectral lines of any wavelength with independent tuning within the gain profile of the dye. 相似文献
52.
A distributed feedback dye laser arrangement is described which can generate pulses at the subharmonic wavelengths of the main excimer laser lines (308 nm, 248 nm, 193 nm, etc.). The laser can be pumped with broadband lasers, such as the XeCl* laserpumped dye laser with competing cavities. The laser is designed to be used as a part of a femtosecond, terawatt excimer laser system. 相似文献
53.
M. Borówko A. Patrykiejew S. Sokołowski R. Zagórski O. Pizio 《Czechoslovak Journal of Physics》1998,48(3):371-388
The Monte Carlo simulation method introduced by Smith and Triska [J. Chem. Phys.100 (1994) 3019] is extended to the case of a reacting fluid in contact with a hard wall. The fluid structure for both spherical
and nonspherical reaction products is discussed for simple models of reacting hard spheres near a hard wall and near a wall
interacting via Lennard-Jones (9,3) potential. In the latter case the investigated model assumes that the probability of a
chemical reaction changes with a distance from the surface. It is shown that the applied technique is suitable for the study
of reacting nonuniform fluids.
This work is supported by KBN under the Grant No. 3 T09A 062 10. 相似文献
54.
9-Chlorobicyclo[6.1.0]non-l(9)-ene ( 4 ), a 2-chlorinated 1,3-fused cyclopropene, is synthesized and isolated from the dehalogenation of the l-bromo-9,9-dichlorobicyclo[6.1.0]nonane, itself derived from cyclooctene. Compound 4 undergoes ring opening reaction to generate cyclooctenyl chlorocarbene ( 9 ) which reacts with water via conjugate addition and ipso-addition to give ( E )-2-(chloromethylene)cyclooctanol ( 7 ) and cyclooctene-l-carboxaldehyde ( 8 ), respectively. The conjugate addition of 9 with water is more favorable than the ipso-addition by 3:1. Compound 4 , which is stable at ?25 °C for weeks without any decomposition, reacts with oxygen to produce 2-chlorocyclonon-2-enone ( 12 ) via the ring-opening reaction adduct, vinyl alkylcarbene 10 . 相似文献
55.
Pier Luigi Stanghellini Livio Cognolato György Bor Sidney F. A. Kettle 《Journal of chemical crystallography》1983,13(2):127-133
13C-enriched carbido carbonyl clusters of the type [M6C(CO) n ] z? (M=Fe,n=16,z=2; M=Ru,n=16 ifz=2 andn=17 ifz=0) have been prepared and their IR spectra observed in the 900?600 cm?1 region; the band shifts occurring upon13 C substitution enable the assignment to the stretching modes of the interstitial C atom. Band patterns reflect the symmetry of the M6C core, but the frequencies seem dependent on other molecular features. 相似文献
56.
57.
A theoretically predicted phenomenon, the spatially inhomogeneous saturation of the gain caused by amplified spontaneous emission, was investigated. The direct measurements of the population of excited states are in good qualitative agreement with the theoretical calculations. 相似文献
58.
59.
Jin-Long Chen Yuo-Hsien Shiau Hung-Wen Chiu Niels Wessel Jürgen Kurths Woei-Chyn Chu 《Physica A》2010,389(9):1861-1868
Despite many previous studies on the association between hyperthyroidism and the hyperadrenergic state, controversies still exist. Detrended fluctuation analysis (DFA) is a well recognized method in the nonlinear analysis of heart rate variability (HRV), and it has physiological significance related to the autonomic nervous system. In particular, an increased short-term scaling exponent α1 calculated from DFA is associated with both increased sympathetic activity and decreased vagal activity. No study has investigated the DFA of HRV in hyperthyroidism. This study was designed to assess the sympathovagal balance in hyperthyroidism. We performed the DFA along with the linear analysis of HRV in 36 hyperthyroid Graves’ disease patients (32 females and 4 males; age 30 ± 1 years, means ± SE) and 36 normal controls matched by sex, age and body mass index. Compared with the normal controls, the hyperthyroid patients revealed a significant increase (P<0.001) in α1 (hyperthyroid 1.28±0.04 versus control 0.91±0.02), long-term scaling exponent , overall scaling exponent , low frequency power in normalized units (LF%) and the ratio of low frequency power to high frequency power (LF/HF); and a significant decrease (P<0.001) in the standard deviation of the R-R intervals (SDNN) and high frequency power (HF). In conclusion, hyperthyroidism is characterized by concurrent sympathetic activation and vagal withdrawal. This sympathovagal imbalance state in hyperthyroidism helps to explain the higher prevalence of atrial fibrillation and exercise intolerance among hyperthyroid patients. 相似文献
60.
The composite of silver-modified lithium manganese oxide were prepared using thermal decomposition method of different mole
ratio. Structural characterization was carried out by X-ray diffraction (XRD). XRD analysis revealed different patterns as
the content of the dopant in the spinel increases. Phase analysis shows that Ag particles were dispersed on the LiMn2O4 surface instead of entering the spinel structure. On the other hand, the electrochemical behavior of cathode powder was examined
by using two-electrode test cells consisting of a cathode, metallic lithium as anode, and a solid polymer electrolyte of 0.87PEO-0.13LiCF3SO3-0.10DBP. According to the electrochemical tests results, the influence of the Ag additive content on the electrochemical
properties of Ag/LiMn2O4 composites is clearly shown. 相似文献