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1.
B. G. Sidharth 《Foundations of Physics Letters》2006,19(6):611-617
In this note we consider a variable G cosmology which is consistent with observation and which had successfully predicted an ever expanding accelerating universe
with a small cosmological constant amongst other things. Three further tests are proposed in this note: First, the inexplicable
anomalous accelerations of the Pioneer spacecrafts can be explained. It is then shown that the observed shortening of the
orbital periods of binary pulsars is in good agreement with this model. Finally, more general changes in orbital parameters
are deduced, which may be observed in the future. 相似文献
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Organic sulfonyl fluorides are of interest owing to their insecticidal, germicidal and enzyme inhibitory properties. In the current work, synthesis of p-toluenesufonyl fluoride was accomplished by reacting p-toluenesulfonyl chloride with solid potassium fluoride using PEG-400 as a catalyst under solid-liquid phase transfer catalysis (S-L PTC) at 30 °C. p-Toluenesulfonyl fluoride is used as peroxygen bleach activator. It also finds use in the treatment of Alzheimer's disease. The mechanism is based on homogeneous solubilization of solid. PEG forms a complex with metal cation which associates with the nucleophile and it participates in SN2 type reactions. The reaction is intrinsically kinetically controlled. A complete theoretical analysis is done to determine both the rate constant and equilibrium constant from the same set of data. The activation energy and Gibbs free energy are also calculated. 相似文献
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R. T. Chitnis S. G. Talnikar V. A. Thakur A. H. Paranjape 《Journal of Radioanalytical and Nuclear Chemistry》1979,49(1):63-70
The method for plutonium determination based on secondary controlled-potential coulometry, as described by SHULTS, is applied
for analysis in the range of 0.1–5 mg plutonium. The method involves the oxidation of plutonium to Pu(VI) with perchloric
acid followed by its reduction by an internally generated ferrous mediator. This is a two step procedure, involving the reduction
of Pu(VI) and Fe(III) to a mixture of Pu(III) and Fe(II), followed by the oxidation of Pu(III) and Fe(II) to Pu(IV) and Fe(III),
respectively. The net results is the reduction of Pu(VI) to Pu(IV), measured as the difference between the currents consumed
during the reduction and oxidation steps. The original method of SHULTS involves 10–25 mg plutonium for each determination.
Since the present method is intended for the analysis of smaller amounts of plutonium, the oxidation procedure described in
the original version had to be modified. The method is found to work satisfactorily with a precision better than 0.1% at 5
mg level and 1.2% for 0.1 mg plutonium. 相似文献
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Noble V. Thomas Vidya Sathi Ani Deepthi Sruthi Sudheendran Leena Sidharth Chopra 《Journal of heterocyclic chemistry》2021,58(1):48-55
A simple and efficient method, proceeding through a new mechanistic pathway, for the synthesis of spiro[indoline-3,4-thiopyrano[2.3-b]indole derivatives have been developed by exploiting the reaction of thieno[2,3-b]indole-2,3-dione with N-substituted isatilidenes. The compounds synthesized have been screened for antibacterial activity. The generality of the reaction and mechanistic rationale are presented. 相似文献