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61.
Santosh Kumar Sejy Lee Reju George Thomas Seung‐Jea Lee Hong‐Joon Lee In‐Kyu Park Yong Yeon Jeong Tae‐Ho Yoon Dong‐Chan Shin Jae‐Suk Lee 《Journal of polymer science. Part A, Polymer chemistry》2019,57(11):1165-1172
Self‐emulsion polymerization (SEP), a green route developed by us for the polymerization of amphiphilic monomers, does not require any emulsifier or an organic solvent except that the water‐soluble initiators such as 2,2′‐azobis[2‐(2‐imidazolin‐2‐yl)propane]dihydrochloride (VA‐044) and potassium persulfate (KPS) are only used. We report here the polymer nanoscaffolds from a number of amphiphilic monomers, which can be used for in situ encapsulation of a variety of nanoparticles. As a demonstration of the efficacy of these nanoscaffolds, the synthesis of a biocompatible hybrid nanoparticle (nanohybrid), prepared by encapsulating Fe3O4 magnetic nanoparticle (Fe3O4 MNPs) in poly(2‐hydroxyethyl methacrylate) in water, for MRI application is presented. The nanohybrid prepared following the SEP in the form of an emulsion does not involve the use of any stabilizing agent, crosslinker, polymeric emulsifier, or surfactant. This water‐soluble, spherical, and stable nanohybrid containing Fe3O4 MNPs of average size 10 ± 2 nm has a zeta potential value of ?41.89 mV under physiological conditions. Magnetic measurement confirmed that the nanohybrid shows typical magnetic behavior having a saturation magnetization (Ms) value of 32.3 emu/g and a transverse relaxivity (r2) value of 29.97 mM?1 s?1, which signifies that it can be used as a T2 contrast agent in MRI. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 相似文献
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Sunanda Banerjee Rohini M Godbole Sreerup Raychaudhuri Ben Allanach Sunanda Banerjee Satyaki Bhattacharyya Debajyoti Choudhury Siba Prasad Das Anindya Datta Rohini M Godbole Monoranjan Guchait Sabine Kraml Gobinda Majumdar David Miller Margarete Mühlleitner Nobuchika Okada Maxim Perelstein Santosh K Rai Sreerup Raychaudhuri Saurabh D Rindani DP Roy K Sridhar Rishikesh Vaidya D Zeppenfeld 《Pramana》2006,67(4):617-637
This is summary of the activities of the working group on collider physics in the IXth Workshop on High Energy Physics Phenomenology
(WHEPP-9) held at the Institute of Physics, Bhubaneswar, India in January 2006. Some of the work subsequently done on these
problems by the subgroups formed during the workshop is included in this report. 相似文献
64.
Santosh B. Rahane Andrew T. Metters S. Michael Kilbey II 《Journal of polymer science. Part A, Polymer chemistry》2010,48(7):1586-1593
A kinetic model developed to investigate surface‐initiated photoiniferter‐mediated photopolymerization (SI‐PMP) and parameterized using experimental thickness data from SI‐PMP of methyl methacrylate is used to examine chain extension by reinitiation. Specifically, the effects of light intensity, concentration of an added deactivator, tetraethylthiuram disulfide (TED), and initial photoiniferter (PI) concentration on the reinitiation ability of surface‐tethered PMMA layers is examined in detail. The simulations show that while increases in [TED] and decreases in light intensity affect overall rates of PMMA layer growth in a similar fashion, their effect on reinitiation ability of PMMA layers is significantly different: reinitiation ability increases with increasing [TED] but it is not improved by decreases in light intensity. Simulations also suggest that polymer layers synthesized in the presence of TED have a greater tendency to form surface‐tethered block copolymers upon reinitiation compared with polymer layers synthesized without TED and at lower light intensity. While both [PI] and [TED] affect the reinitiation ability, the effect of [TED] on reinitiation ability is identical at a given [TED]/[PI] ratio for all PI and TED concentrations tested. These findings obtained from the rate‐based model are instrumental in delineating strategies for creating tethered block copolymer layers or mixed brushes by SI‐PMP. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1586–1593, 2010 相似文献
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Santosh RajputChao-wei Leu Kasey WoodDavid StC Black Naresh Kumar 《Tetrahedron letters》2011,52(52):7095-7098
The activated dimethoxypyrrolo[3,2,1-ij]quinolin-6-one ring system was synthesized via two approaches, starting from an indole and quinolin-4-one, respectively. Subsequent demethylation led to both monohydroxy- and dihydroxypyrrolo[3,2,1-ij]quinolin-6-ones. 相似文献
67.
Srivastava Santosh Weissler G. L. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1973,1(4):17-22
The lowering of the ionization potentials of hydrogen and carbon atoms immersed in a high temperature and high density thermal plasma generated in a wall stabilized arc have been estimated from the advance or shift of their respective series limits in the vacuum ultraviolet region of the spectrum for different electron densities and temperatures. Results show a close agreement with those theoretical calculations in which the effects of both microfield and polarization terms are added. However, our electron densities are lower by about two orders of magnitude than the critical electron densities required by theory for the inclusion of the microfield term. The question of validity of a critical electrom density will be discussed. 相似文献
68.
[reaction: see text] The stereoselective intramolecular reductive etherification of delta-trialkylsilyloxy substituted ketones with catalytic bismuth tribromide and triethylsilane provides a convenient method for the construction of cis-2,6-disubstituted tetrahydropyrans. This method was highlighted in the key step of an expeditious total synthesis of the antibiotic, (-)-centrolobine. 相似文献
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