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921.
922.
A sensitive staining method for the detection of oxytocinase (EC 3.4.11.3) activity in electrophoresis gels has been described. The method is based on the enzymatic release of p-nitroaniline (PNA) from two specific synthetic oxytocinase substrates, S-benzyl-L-cysteine-p-nitroanilide (BCN) and L-leucine-p-nitroanilide (LN), respectively. The PNA is then diazotized with sodium nitrite and subsequently coupled to a chromogen, N-(1-naphthyl)-ethylenediamine dihydrochloride (NED) to produce a deep pink/magenta colored azo-dye at the site of oxytocinase activity. 相似文献
923.
S I Madanshetty R A Roy R E Apfel 《The Journal of the Acoustical Society of America》1991,90(3):1515-1526
In this work acoustic microcavitation in water is studied primarily at 0.75 MHz and 1% duty cycle. To detect cavitation, two kinds of acoustic detectors are used. The first one is an unfocused, untuned 1-MHz receiver transducer that serves as a passive detector. The other one is a focused 30-MHz transducer that is used in pulse-echo mode and is called the active detector. Cavitation itself is brought about by a focused PZT-8 crystal driven in pulse mode. The active detector is arranged confocally with respect to the cavitation transducer. Both the interrogating pulse and the cavitation pulse arrive simultaneously at the common focus, which is the region of cavitation. With the test chamber filled with clean water, no cavitation is observed, even when the cavitation transducer is driven to give its peak output of 22 bar peak negative. Cavitation is, however, observed when polystyrene microparticles are added to the host water. Our view of how these smooth, spherical, monodispersed microparticles give rise to cavitation is described with some estimates. An attempt has been made to understand whether the presence of "streaming" affects the thresholds, and it has been found that the active detector field affects the cavitation process. 相似文献
924.
925.
A. Roy Chowdhury M. Debnath R. S. Banerjee 《International Journal of Theoretical Physics》1989,28(1):127-133
We consider the inverse problem for a three-wave interaction system in a manner different from Zakharovet al. and of Kaup. Our method is an adaptation of the technique due to Date to a 3 × 3 Lax pair. The analysis leads to a system of ordinary nonlinear equations for the
ivariables linearizable through a suitable definition of differential on a Riemann surface. Next, in the degenerate case, when the
iare equal in pairs, we prove that such a set of equations is exactly integrable and leads to solitary solutions. 相似文献
926.
The swinging Atwood machine, a prototype nonlinear dynamical system, is analyzed following an idea of Bogoliubov and Mitropolsky. A series solution is found for the radial and angular displacement as functions of time. The analysis is repeated in the resonance case, when the frequency of the driving force maintains a fixed ratio to that of the free motion. The condition of resonance requires the mass ratio to be equal to 2j
2–1, wherej is an integer not equal to one. 相似文献
927.
A homogeneous Bianchi type VIh cosmological model filled with perfect fluid, null electromagnetic field and streaming neutrinos is obtained for which the free gravitational field is of the electric type. The barotropic equation of statep = (–1) is imposed in the particular case of Bianchi VI0 string models. Various physical and kinematical properties of the models are discussed. 相似文献
928.
Sudeshna Chakravorty A. Roy Chowdhury S. N. Paul 《International Journal of Theoretical Physics》1992,31(2):343-352
We analyze the effect of a nonzero streaming velocity of both positive and negative ions on the formation of solitary waves in a relativistic plasma. The thermodynamic situation is considered to be isothermal. For various values ofu
0/C andn
o/nowe obtain the variations of the amplitude and the width of the solitary wave. 相似文献
929.
930.