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61.
17O NMR data are reported for 3-pentanol ( 1 ), cyclopentanol ( 2 ), cyclohexanol ( 3 ), and cycloheptanol ( 4 ). The 17O NMR signals for 1–4 appeared as doublets, shown to arise from proton–oxygen coupling (1JOH = 76 ± 3 Hz) by proton decoupling experiments. The effect of concentration, temperature, and solvent was examined in detail for 2 . Proton—oxygen coupling was observed at low concentrations, decreased at lower temperatures, and was sensitive to solvent. 相似文献
62.
Pratap V Moumen N Subramanian RS 《Langmuir : the ACS journal of surfaces and colloids》2008,24(9):5185-5193
63.
R. Subramanian 《Applied Scientific Research》1970,22(1):89-96
Stresses are calculated for a small elastic inclusion bonded (in a way to ensure continuous displacements and tractions across
the surface of the inclusion) to a large circular cylindrical shaft. The inclusion considered is inhomogeneous and of spherical
shape. The shear modulus of the inclusion is assumed to be μ0 exp(−1/2β2
r
2). Some special cases are also discussed. 相似文献
64.
Paramasivam Manisankar Subramanian Viswanathan Halliah Gurumallesh Prabu 《International journal of environmental analytical chemistry》2013,93(5):389-397
Electrochemical studies of direct orange 8 were carried out with a bare glassy carbon electrode (GCE) and a polypyrrole-coated GCE in aqueous acetonitrile medium using voltammetric techniques. One reversible couple around 0.3?V due to the redox reaction of the phenol group, one reduction peak around ?0.4?V due to reduction of the azo group and one oxidation peak around 1.0?V due to oxidation of the amino group were observed. Chronocoulometric studies revealed dye adsorption on the GCE. A square-wave stripping method was developed for the determination of the dye at pH 13.0, and a linear calibration equation obtained. The reproducibility in the measurement of peak currents was confirmed from the RSD value 2.8% at 0.001?mg?mL?1 concentration. A comparison of the stripping voltammetric method with the UV-Vis spectrophotometric method was made. The determination limits are wider and the RSD value is lower in the stripping voltammetric method. The concentration of the dye present in dye effluent was determined using this method. 相似文献
65.
66.
S. Lal R. Raghavan T. N. Rangaswamy B. V. Sreekantan A. Subramanian S. D. Verma S. C. Tonwar R. H. Vatcha 《Proceedings Mathematical Sciences》1971,73(4):170-178
Detailed features of extremely collimated nuclear interactions induced by cosmic ray particles in carbon and brass (belonging to group I as classified in Part I of this series of papers) are presented. These extremely collimated nuclear interactions seem to be preferentially induced by pions rather than by nucleons; also the relative frequency of these seems to be less when brass is used as target compared to the case with carbon as target. The distribution of multiplicities of secondary particles emitted in the forward direction show certain regularities in the case of interactions induced by charged primaries. Observations on the γ-rays associated with these events give support to the interpretation that in these inelastic collisions pions are produced in pairs in the forward direction with low transverse momentum. It is suggested that such a low energy di-pion system could be the same as found in the so-called ABC effect. 相似文献
67.
68.
This paper discusses the availability of a two-unit standby redundant repairable system in which the pdf of the life time of the online unit depends on the time it has spent in the standby state before it is switched online. Explicit expressions for the Laplace transforms of the availability and reliability of the system are obtained by identifying suitable regeneration points.
Zusammenfassung In dieser Arbeit wird die Verfügbarkeit eines redundanten 2-Komponentensystems mit heißer Reserve und Reparatur betrachtet. -Die Lebensdauerverteilung der Betriebskomponente hängt von der Länge der Zeit ab, die sie vorher als Reservekomponente verbracht hat. Es werden explizite Ausdrücke der Laplacetransformierten für die Verfügbarkeit und Zuverlässigkeit des Systems ermittelt, indem geeignete Regenerationspunkte verwendet werden.相似文献
69.
Priv.-Doz. Dr. K. -P. Kistner Dr. R. Subramanian 《Mathematical Methods of Operations Research》1974,18(3):117-129
Zusammenfassung Es wird die Zuverlässigkeit eines Systems mit mehreren redundanten Einheiten untersucht, bei dem nicht nur die tätige Einheit, sondern auch die Reserveeinheiten ausfallen und bei dem gestörte Einheiten repariert werden können. Es wird vorausgesetzt, daß die Reparaturzeiten und die Lebensdauern der Reserveeinheiten exponentialverteilt sind, während die Betriebsdauern der tätigen Einheiten, unabhängig von ihrem Alter beim Einsatz, beliebig verteilt sind.Unter diesen Voraussetzungen werden die mittlere Zeit bis zum Ausfall des Systems und die langfristige Verfügbarkeit des Systems explizit für den Fall dreier Einheiten bestimmt.Am Beispiel doppel-exponentialverteilter Betriebsdauern werden die Abhängigkeit dieser Größen von der Reparaturgeschwindigkeit untersucht und die optimale Reparaturrate bestimmt.
Diese Arbeit wurde durch den Sonderforschungsbereich 21 — ökonometrie und Unternehmensforschung — und ein Stipendium der Alexander-von-Humboldt-Stiftung gefördert. 相似文献
Summary We consider the reliability of a repairable system with several stand-by redundant units, where not only the working unit but also the spares are subject to failure. We assume, that repair-times and life-times of spares are exponentially distributed, whereas the time to failure of a working unit is — independent of its age at the time of switch-on — arbitrarily distributed.Using these assumptions, we derive the expected time to system-failure and the steady-state availability explicitely for the case of three redundant units. The example of double-exponentially distributed working-times is used to examine the dependancy of these characteristics on repair-times, and to calculate the optimal repair-rate.
Diese Arbeit wurde durch den Sonderforschungsbereich 21 — ökonometrie und Unternehmensforschung — und ein Stipendium der Alexander-von-Humboldt-Stiftung gefördert. 相似文献
70.