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Chemoselective esterification of phenolic acids with dialkyl sulphates or alkyl halides in the presence of sodium bicarbonate in 1,3‐dialkylimidazolium ionic liquids is reported in excellent yields and less reaction time as compared to organic solvents. 相似文献
3.
Jena Sudipta Ray Asit Sahoo Ambika Kamila Pradeep Kumar Nayak Sanghamitra Panda Pratap Chandra 《Chemistry of Natural Compounds》2021,57(6):1147-1149
Chemistry of Natural Compounds - 相似文献
4.
Nanosized cobalt ferrite spinel particles have been prepared by using mechanically alloyed nanoparticles. The effects of various preparation parameters on the crystallite size of cobalt ferrite which includes milling time; ball-to powder weight ratio (BPR) and sintering temperature, were studied using X-ray diffractometer (XRD). Scherrer's equation was used to study the crystallite size evolution of the as-prepared materials. The results of the as-milled sample revealed that both milling time and BPR plays a role in determining the crystallite size of the milled powder. However, where sintering is involved, the sintering temperature results in grain growth, and thus plays a dominant role in determining the final crystallite size of the samples sintered at higher temperature (above 900 °C). From the vibrating-sample magnetometer (VSM) measurement it was observed that the coercivity of the as-milled samples without sintering is almost negligible, which is a type characteristic of superparamagnetic material. However, for the sintered samples, the saturation increases while coercivity decreases with increases sintering temperature. 相似文献
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Proceedings - Mathematical Sciences - 相似文献
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We present a graphical analysis of the mechanisms underlying the occurrences of bubbling sequences and bistability regions
in the bifurcation scenario of a special class of one dimensional two parameter maps. The main result of the analysis is that
whether it is bubbling or bistability is decided by the sign of the third derivative at the inflection point of the map function. 相似文献
10.
This paper is a review of the present status of studies relating to occurrence of deterministic chaos and its characterization
in one-dimensional maps. As our primary aim is to introduce the nonspecialists into this fascinating world of chaos we start
from very elementary concepts and give sufficient arguments for clarity of ideas. The two main scenarios during onset of chaos
viz. the period doubling and intermittency are dealt with in detail. Although the logistic map is often discussed by way of
illustration, a few more interesting maps are mentioned towards the end. 相似文献