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891.
892.
Lyoluminescence of luminol induced by -irradiated NaCl has been studied in aqueous amines. The emission spectra of lyoluminescence are recorded on 400 ASA Kodak film using a Fuess spectrograph. A broad continuous emission band appears in the visible region from 390 to 500 nm. The emission band showed two peaks centered at 430 and 470 nm. The 430 nm peak is more intense in secondary amines while the 470 nm band is more intense in primary amines. The mechanism of light emission is based on the comparative study of lyoluminescence, fluorescence and chemiluminescence of luminol in aqueous amines.  相似文献   
893.
The electrochemical production and doping of soluble, as well as the physicochemical properties of a soluble electrically conducting polymer based on 3-methyl-4-phenylthiophene were studied.Translated from Teoreticheskaya i Éxperimental'naya Khimiya, Vol. 29, No. 2, pp. 143–148, March–April, 1993.The authors would like to express gratitude to the State Committee of the Ukraine on questions of science and technology for financial support for this work within the framework of the State Scientific and Technical Program 7.1. Materials for Electronic Technology, as well as to V. P. Kandilenko and V. Ya. Chernov for aid in recording the fluorescence spectra of the P3M4PT films.  相似文献   
894.
Electroanalytical methods based on biosensor technology and differential pH measurement for the determination of l-lactic and l-malic acids in wine were developed. Lactic acid was determined according to two procedures consisting of the use of two lactate electrochemical biosensors, one based on a Clark O(2) probe and the other based on the H(2)O(2) probe. The two probes were assembled employing a polymeric membrane where the enzyme lactate oxidase was previously immobilized. Both sensors exhibited high storage and operational stabilities, and good reproducibility when used in wine matrix. Measurement of lactate was carried out using two different flow-through cells assembled with the lactate probes. The low detection limit of these probes and the relatively high concentration of lactate in wine samples required a serial dilution in the range 1:100 to 1:200, thus eliminating all potential electrochemical or enzyme interferences present in the sample. Malic acid was determined using a differential commercially available pH-meter and an enzymatic procedure. For this analysis, we employed the malic enzyme (EC 1.1.1.40) and the NADP(+) cofactor. The pH variation due to the action of this enzyme on malic acid was found to be proportional to the malic acid present in the sample. Experimental parameters such as pH, temperature, and co-factor concentration were optimized, resulting in malate determination in less than 1 min with good reproducibility. Various samples of wine and wine musts were assayed for lactate with the two biosensor procedures, and for malate with differential pH-metry. The results when compared with those obtained with the commonly used spectrophotometric procedure correlated well.  相似文献   
895.
896.
LetG R be the graph obtained by joining all sites ofZ d which are separated by a distance of at mostR. Let (G R ) denote the connective constant for counting the self-avoiding walks in this graph. Let (G R ) denote the coprresponding constant for counting the trees embedded inG R . Then asR, (G R ) is asymptotic to the coordination numberk R ofG R , while (G R ) is asymptotic toek R. However, ifd is 1 or 2, then (G R )-k R diverges to –.Dedicated to Oliver Penrose on this occasion of his 65th birthday.  相似文献   
897.
The devices and systems for EHF therapy and diagnosis of the BAYuR series are examined and compared with known analogs.Scientific-Research Measuring-Systems Institute. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 37, No. 1, pp. 155–157, January, 1994.  相似文献   
898.
899.
There is an intriguing discrepancy between values measured directly at the CERNZ 0-factory and low-energy (at few GeV) measurements transformed toQ=M z0 by a massless QCD evolution relation. There exists and attempt to reconcile this discrepancy by introducing a light gluinog in the MSSM. We study in detail the influence of heavy thresholds on evolution. First, we construct the exact explicit solution to the mass-dependent two-loop RG equation for the running . This solution describes heavy thresholds smoothly. Second, we use this solution to recalculate a new values corresponding to low-energy input data. Our analysis demonstrates that usingmass-dependent RG procedure generally produces corrections of two types: Asymptotic correction due to effective shift of threshold position; Local threshold correction only for the case when input experiment lies in the close vicinity of heavy particle threshold:Q expt -M h . Both effects result in the effective shift of the values of the order of 10–3. However, the second one could be enhanced when the gluino mass is close to a heavy quark mass. For such a case the sum effect could be important for the discussion of the light gluino existence as it further changes theg mass.Work supported in part by INTAS-93-1180  相似文献   
900.
The intermittency phenomenon is investigated in proton-gold, oxygen-gold, sulphur-gold and sulphur-sulphur collisions at 200 GeV per nucleon. The data were taken with the NA 35 streamer chamber detector at the CERN SPS. The data samples are carefully corrected for double counting of tracks and for contamination from photon conversions, particle decays and secondary interactions. The analysis is carried out in terms of factorial moments, using a new definition, and of correlation integrals. Both methods show the presence of nonstatistical fluctuations (intermittency). The main conclusions are: The observation of the effect for pairs of hadrons with negative charges and its near absence for pairs of opposite charges is consistent with the assumption that Bose-Einstein correlations yield the dominant contribution. The intermittency effect is not proportional to (dn/dy)–1 which would be expected in superposition models. The measured relation between the second and third factorial moment for negative hadrons indicates that genuine 3-particle correlations are small. The predictions of a Monte Carlo simulation which is based on the Lund Fritiof model with the inclusion of Bose-Einstein correlations agree with the experimental results.Deceased  相似文献   
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