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801.
We show that, in dimensions equal or greater than three, classical strings do not join or split. This is part of a no-interaction theorem that is also proved. The quantum theory is considered. 相似文献
802.
803.
S. Guizard D. Chapoulard M. Horani D. Gauyacq 《Applied physics. B, Lasers and optics》1989,48(6):471-477
Resonantly enhanced multiphoton ionization (REMPI) is proposed as an ultrasensitive detection method forreal-time monitoring of atmospheric pollutants in situ. The technique is demonstrated in the laboratory for NO diluted in pure nitrogen at 560 mbar. The MPI current resulting from (2+1) photon ionization of NO via the resonantC
2
H (v=0) state has been measured for several NO concentrations. Detection levels as low as 50 ppt have been obtained.Laboratoire associé à l'Université de Paris-Sud 相似文献
804.
S. P. Tretyakova Yu. S. Zamyatnin V. N. Kovantsev Yu. S. Korotkin V. L. Mikheev G. A. Timofeev 《Zeitschrift für Physik A Hadrons and Nuclei》1989,333(4):349-353
The emission of Ne and Mg nuclei was detected in the spontaneous decay of234U with probabilities of, respectively, (3.9 ±1.0) × 10?13 and (2.3 ±0.7) × 10?13 relative toα-decay. The upper limits of this kind of decay for235U and236U have been established. Systematics of half-lives for cluster emission are found to be similar to the Geiger-Nuttall dependence forα-decay. Some evidence for the presence of hindrance to cluster emission from the odd-mass nuclei233U and235U is obtained. 相似文献
805.
J E Paanakker J M Thio H M Van den Wildenberg F M Kaspersen 《Journal of chromatography. A》1987,421(2):327-335
An assay has been developed and validated for the routine monitoring of vecuronium in plasma. It consists of solid-phase extraction using C18 disposables as sample pre-treatment, high-performance liquid chromatography and post-column ion-pair extraction with fluorimetric detection. The fluorescent anion 9,10-dimethoxyanthracene-2-sulphonate (DAS) is used as the counter ion. The detection limit is ca. 5 ng/ml in plasma with a signal-to-noise ratio of 10. The assay is also applicable for monitoring vecuronium and its potential metabolites in other biological media, e.g., urine, bile and tissue (liver, kidney) homogenates. 相似文献
806.
807.
808.
Conclusions When formamide was reacted with phosphorous acid and phosphorus trichloride, the formation of iminobis(methylenediphosphonic) acid was detected.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 865–868, April, 1987.The authors wish to express their graditude to Yu. P. Tsentalovich for helping with the NMR spectral analysis. 相似文献
809.
T.S. Khlebnicova V.G. Isakova A.V. Baranovsky E.V. Borisov F.A. Lakhvich 《Journal of fluorine chemistry》2006,127(12):1564-1569
A one-pot synthesis of 2-perfluoroalkanoylcyclohexane-1,3-diones via C-acylation of cyclohexane-1,3-diones with N-perfluoroacylimidazole as an acylating agent is reported. A reaction was examined with isolated N-trifluoroacetylimidazole and with N-perfluoroacylimidazoles generated in situ from perfluorocarboxylic acid anhydrides or perfluorocarboxylic acids. 相似文献
810.
Experimental Techniques - MDRMIN consists of k numbers of identical N/k multistage networks in k planes having k × 1 multiplexers and 1 × k demultiplexers at input and output,... 相似文献