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101.
102.
103.
An expedient route to tetracyclo[6.5.2.02,7.09,13]pentadec-2(7),11-dien-14-one and tetracyclic framework of conidiogenol have been reported. Cycloaddition of annulated cyclohexa-2,4-dienone with cyclopentadiene, photochemical oxa-di-π-methane reaction and a highly unusual dehalogenation of bridgehead halogen are the key features of our methodology. 相似文献
104.
105.
This paper derives an upper bound for the speedup obtainable by any parallel branch-and-bound algorithm using the best-bound search strategy. We confirm that parallel branch-and-bound can achieve nearly linear, or even super-linear, speedup under the appropriate conditions.This work was supported by U.S. Army Research Office grant DAAG29-82-K-0107. 相似文献
106.
107.
The construction of the second constant of motion of second order for two-dimensional classical systems is carried out in
terms ofz=q
1 +iq
2 andq=q
1 −iq
2. As a result a class of Toda-type potentials admitting second order invariants is explored. 相似文献
108.
109.
A cylindrically symmetric inhomogeneous cosmological model with electromagnetic field for perfect fluid distributions is obtained. To get a determinate solution, a supplementary conditionA=(BC)
n
between metric potentials is used whereA, B, andC are functions of bothx andt andn is a constant. Some physical and geometrical properties of the model and behavior of electromagnetic field tensors are also discussed. 相似文献
110.
Nitin Mehrotra Sreedharan Sabarinath Satyendra Suryawanshi Kanwal Raj Ram Chandra Gupta 《Chromatographia》2009,69(9-10):1077-1082
The herbal medicament derived from the lipid soluble fraction obtained from Curcuma longa L. (Zingiberaceae) has shown potential neuroprotective activity in disorders like stroke. HM has been standardized with three biomarkers: ar-turmerone, α/β-turmerone and curlone, major bisabolane sesquiterpenes of turmeric oil. Development of a biaonalytical method for these sesquiterpenes was initiated to characterize its preclinical pharmacokinetics in rabbits to accelerate its development as a potential candidate for vascular complications. Since, the compounds are structurally and chemically very similar, gradient elution was utilized on a C-18 reversed phase column with a mobile phase comprising of acetonitrile and deionised water. The UV detector was set at wavelengths 240 and 270 nm. The sample clean-up was performed by protein precipitation with acetonitrile. The method was reasonably sensitive with limits of quantitation (LOQ) of 0.098 μg mL?1 in plasma for all the analytes. Accuracy and precision were within the acceptable limits, as indicated by relative standard deviation (% RSD) varying from 1.3 to 13.6% and bias values ranging from ?5.5 to 10.3%, respectively. Moreover, the analytes were stable in plasma even after three freeze-thaw cycles. The method was applied to generate preliminary pharmacokinetics of turmeric oil in rabbits after intravenous administration. 相似文献