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991.
Inversed AOT micelles have been used as a system to simulate peptide-receptor interaction; they encapsulate an aqueous solution of the melanostatin analog HCl·Pro-Tyr-Gy-NH2. NOESY indicates that adsorption at the phase boundary causes the peptide to acquire the biologically active II conformation. The phenyl ring in Tyr is inserted into the cavity formed by the isooctyl moieties of the AOT molecules.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 29, No. 1, pp. 74–80, January–February, 1993.  相似文献   
992.
Serrat FB 《Talanta》1994,41(12):2091-2094
A new method is developed for the calorimetric determination in water of chlorine (free and combined) with 3,3′,5,5′-tetramethylbenzidine. The procedure proposed achieves a detection limit of 2 ng/ml and its sensitivity is greater than that of the methods used at present.  相似文献   
993.
We indicate the classes for which a solution of the problem for a certain nonlinear degenerating parabolic system without initial conditions exists and is unique. The uniqueness conditions are established both in the case where restrictions are imposed on the behavior of solutions ast - and in the case where they are not imposed. The existence is proved for the arbitrary behavior of the right-hand side of the system ast-.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 46, No. 4, pp. 454–456, April, 1994.  相似文献   
994.
Sequences of zeros are described for functionsf, which, in the right half plane, are analytic and satisfy the condition ¦f(z)¦0(1) exp (¦z¦), 0<. A criterion of completeness of a system of exponents in a certain space of functions analytic in a half strip is established.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 46, No. 5, pp. 484–500, May, 1994.  相似文献   
995.
Let A be a C*-algebra. For a A let D(a, A) denote the innerderivation induced by a, regarded as a bounded operator on A,and let d(a, Z(A)) denote the distance of a from Z(A), the centreof A. Let K(A) be the smallest number in [0, ] such that d(a,Z(A)) K(A)||D(a, A)|| for all a A. It is shown that if A isnon-commutative and has an identity then either K(A) = , or K(A) = 1 / 3, or K(A) 1. Necessaryand sufficient conditions for these three possibilities aregiven in terms of the primitive and primal ideals of A. If Ais a quotient of an AW*-algebra then K(A) . Helly's Theorem is used to show that if A is aweakly central C*-algebra then K(A) 1.  相似文献   
996.
997.
998.
Spectrographic data from observations of the polarized weak steplike (with relatively sharp growth t 3 sec and slow decay t 102 sec) solar continuum radioemission are analyzed below. The main results are found using a sweeping spectrograph in the 8–12 GHz frequency range (sweep rate 1 sample per second and frequency resolution 120 MHz) and using the RT-22 radio telescope at the Crimean Astrophysical Observatory (angular resolution 4–6). In a series of events at the leading edge of the continuum a narrow-band frequency drifting emission termed blip-type is found. The degree of continuum circular polarization (p<10%) is low compared to that of the narrow-band component (p20%). Both components of the aforementioned events should be radiating on the second harmonic of the local plasma frequency in the context of a plasma generating mechanism. Based on the model proposed and using the observed degree of circular polarization of each component, we can estimate the strength of the magnetic field within the area of the source and the width of the angular spectrum from the radiating plasma turbulence. The results of analysis of the real microwave events are given below.Radiophysical Research Institute, Nizhnii Novgorod. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 37, No. 7, pp. 874–882, July, 1994.  相似文献   
999.
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   
1000.
We have studied bySR spectroscopy the intermetallicsUTr 2Si2 where Tr=Co, Rh or Pt. Whereas for the Co compound we only get information on the muon localisation site, from the other two materials we obtain information on their electronic properties. We compare the characteristics of theirSR response.  相似文献   
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