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121.
Visible-light-induced aerobic oxidative cyanation of aza-Baylis–Hillman (aza-BH) adducts providing valuable allylic cyanides in good to excellent yields has been developed. The protocol involves in situ formation of 4π conjugated iminium ion intermediates, which undergo cyanation at the γ-position to afford Michael type adducts. This is the first example of visible-light-induced catalytic functionalization of aza-BH adducts using air (O2) as an economical and ecosustainable oxidant and TMSCN as a convenient and readily available cyanide source. 相似文献
122.
Chandan Singh Ratan Kumar Rai Arvind M. Kayastha Neeraj Sinha 《Magnetic resonance in chemistry : MRC》2016,54(2):132-135
Ultra fast magic angle spinning (MAS) has been a potent method to significantly average out homogeneous/inhomogeneous line broadening in solid‐state nuclear magnetic resonance (ssNMR) spectroscopy. It has given a new direction to ssNMR spectroscopy with its different applications. We present here the first and foremost application of ultra fast MAS (~60 kHz) for ssNMR spectroscopy of intact bone. This methodology helps to comprehend and elucidate the organic content in the intact bone matrix with resolution and sensitivity enhancement. At this MAS speed, amino protons from organic part of intact bone start to appear in 1H NMR spectra. The experimental protocol of ultra‐high speed MAS for intact bone has been entailed with an additional insight achieved at 60 kHz. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
123.
124.
Jeong Hoon Ko Arvind Bhattacharya Takaya Terashima Mitsuo Sawamoto Heather D. Maynard 《Journal of polymer science. Part A, Polymer chemistry》2019,57(3):352-359
Amphiphilic self‐folding random copolymers exhibit different solution behaviors depending on the identity of the hydrophobic/hydrophilic units. Herein, it is demonstrated that changing the hydrophilic unit from poly(ethylene glycol) to the sugar trehalose causes increased discrepancy in the polarity difference with a fluorinated hydrophobic segment and changes the aggregation state of the polymer in water. The PEG‐fluorinated and trehalose/PEG‐fluorinated amphiphilic random copolymers were the most efficient at encapsulating a fluorinated agrochemical. The small‐molecule agrochemical exerts a strong influence on the self‐assembly of the polymers, demonstrating that fluorous interactions result in not only intramolecular self‐folding behavior but also intermolecular polymer association to form well‐defined nanoparticles. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 352–359 相似文献
125.
Harsh Mohan Arvind Kumar Jain Gurpreet Kaur Parjit S. Singh Sunita Sharma 《Radiation Physics and Chemistry》2012,81(12):1833-1836
The inner-shell vacancy decay process is consisting of radiative and non-radiative transitions. These investigations have been developing over the last four decades, resulting in close and stringent comparisons of the measured values with the predictions of theoretical models. In view of the current state of affairs, we report in this paper the role of Fluorescence yields, Coster–Kronig transitions and prevailing ionization theories on L X-ray production from Au using low energy protons. Their contribution to these phenomena and current growth will be highlighted. Prospects for supplementary effort will also be discussed. 相似文献
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127.
C. A. Mitchell J. Walker G. Warburton J. Lewkowitsch H. R. Procter H. G. Benett L. Ubbelohde Meister H. Wolff H. C. Sherman M. J. Falk H. Ingle A. S. Fokin H. R. Jensen K. Hazura F. Bedford W. Fahrion A. Eibner H. Muggenthaler D. Holde und J. Marcusson 《Fresenius' Journal of Analytical Chemistry》1913,52(7-8):506-513
Ohne Zusammenfassung 相似文献
128.
129.
Computation of non-linearity parameter (B/A), molecular radius (r
m) and intermolecular free length (L
f) for H2O, C6H6, C6H12, CH3OH, C2H5OH and their deuterium-substituted compounds have been carried out at four different temperatures, viz., 293.15, 303.15, 313.15
and 323.15 K. The aim of the investigation is an attempt to study the isotopic effects on the non-linearity parameter and
the physicochemical properties of the liquids, which in turn has been used to study their effect on the intermolecular interactions
produced thereof. 相似文献
130.