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121.
122.
Terminology is defined, and issues related to providing temporal data integration in a distributed environment are identified. Current technological approaches to the issues are reviewed, and the state of the art is assessed. A unified model for synchronization at three levels, based on previously reviewed approaches, is presented. Directions for future efforts are indicated 相似文献
123.
Summary Five common tricyclic antidepressants are separated on a silica column using an aqueous eluent. The tricyclics are concentrated from serum using an adsorption procedure on a solid phase Sep PakTM C18 cartridge. The method appears to be adequate for monitoring therapeutic levels of these drugs.Dedicated to Professor Dr. István Halász for his 60th birthday. 相似文献
124.
The performance of a large-bore (25-mm) self-heated Sr+ (430.5-nm) recombination laser with longitudinal excitation is discussed in relation to the prospects for scaling average output power to the 5-10-W regime. Average-power scaling is found to be limited in large-bore laser tubes by slow interpulse thermal relaxation in the laser gas mixture with strong radial gradients in species' densities and temperatures at only modest pulse repetition frequencies, leading to premature termination of the population inversion on the tube axis. Proposals for circumventing these limitations in order to permit generation of multiwatt average laser output power at 430.5 nm from Sr + are discussed 相似文献
125.
126.
Desmond Cunningham Mark Little Kevin McLoughlin 《Journal of organometallic chemistry》1979,165(3):287-294
New adducts Et4N(RSnCl4 · L) (R butyl and phenyl; L pyridine, trimethylamine, tri-n-butylphosphine, triphenylphosphine oxide, triphenylarsine oxide, dimethylsulphoxide, dimethylformamide) have been isolated and their Mössbauer spectra studied. Definite structural assignments are made for the phosphine and phosphine oxide adducts from Mössbauer quadrupole splitting data. Comments are made on the choice of partial splitting values for phenyl and butyl groups. 相似文献
127.
128.
A technique is presented for determining the quality of tunable short circuits used as backshorts in waveguide mixers. A backshort, suitable for use in a reduced height 345 GHz Schottky mixer block, has been fabricated in a novel manner and the VSWR determined, using the authors' technique, to be >90 at room temperature.<> 相似文献
129.
Power exchange in tapered optical couplers 总被引:3,自引:0,他引:3
The power exchange between nonparallel optical waveguides or tapered couplers is analyzed by the coupled-mode theory based on local modes of the individual waveguides (local waveguide modes). A self-consistent nonorthogonal coupled-mode formulation is presented and transformed into an orthogonal form which is equivalent to the coupled-mode equations for the local modes of the coupled waveguides (local array modes). The coupled-mode equations are then solved numerically and the effect of the taper on the power exchange between the two guides is studied 相似文献
130.
P Workman C J Little T R Marten A D Dale R J Ruane I R Flockhart N M Bleehen 《Journal of chromatography. A》1978,145(3):507-512