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21.
Kaushal Kumar Mahato Shivesh Sabbarwal Nira Misra 《International Journal of Polymer Analysis and Characterization》2020,25(5):353-361
Abstract Hydrogel composites from polyvinyl alcohol and chitosan have been developed by various researchers as a function of their composition for various medical applications. Although, the solubility of chitosan in acidic solvents may limit its wide bioengineering applications. In this article, we demonstrate that polyvinyl alcohol-chitosan oligosaccharide (water soluble) to develop cross-linked hydrogel network using chemical cross linker. X ray diffraction, Fourier transform infrared spectroscopy, and wettability study of these hydrogels were also performed. Lomefloxacin drug was loaded into the hydrogels and its release profile was studied. 相似文献
22.
The crude saponin obtainable from Marsilea minuta Linn on acid hydrolysis yielded a mixture of sapogenols. The major sapogenol named Marsileagenin A was found to be a hexahydroxy triterpene of oleanene series. From a study of various spectrometric data together with chemical reactions the structure of this sapogenol has been assigned as olean-12-ene-2α, 3β, 16β, 21β, 22α, 28-hexol (1a). 相似文献
23.
Using the KKM mapping technique, we obtain existence results for the mixed equilibrium problem (under the relaxed \(\alpha \)-monotonicity assumption on the bi-function) in a reflexive Banach space. Several examples are given to show that our definition of \(\alpha \)-monotonicity and, hence, our results are more general than that in the existing literature. 相似文献
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In this present article, we study the fractional Hankel transform and its inverse on certain Gel'fand‐Shilov spaces of type S. The continuous fractional wavelet transform is defined involving the fractional Hankel transform. The continuity of fractional Hankel wavelet transform is discussed on Gel'fand‐Shilov spaces of type S. This article goes further to discuss the continuity property of fractional Hankel transform and fractional Hankel wavelet transform on the ultradifferentiable function spaces. 相似文献
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Ayan Chatterjee Chiranjit Mahato Dibyendu Das 《Angewandte Chemie (International ed. in English)》2021,60(1):202-207
Biocatalytic reaction networks integrate complex cascade transformations via spatial localization of multiple enzymes confined within the cellular milieu. Inspired by nature's ingenuity, we demonstrate that short peptide‐based cross‐β amyloid nanotubular hybrids can promote different kinds of cascade reactions, from simple two‐step, to multistep, to complex convergent cascades. The compartmentalizing ability of paracrystalline cross‐β phases was utilized to colocalize sarcosine oxidase (SOX) and hemin as an artificial peroxidase. Further, the catalytic potential of the amyloid nanotubes with ordered arrays of imidazoles were used as hydrolase mimic. The SOX‐hemin amyloid nanohybrids featuring a single extant enzyme could integrate different logic networks to access complex digital designs with the help of three concatenated AND gates and biologically relevant stimuli as inputs. 相似文献
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An aprotic imidazole based zwitterionic-salt, 4-(3-methylimidazolium)-butane sulfonate has been found to be an efficient organocatalyst for tetrahydropyranylation by the reaction of 3,4-dihydro-2H-pyran (DHP) and different aliphatic alcohols as well as various phenolic compounds. The notable advantages of the present method are general applicability to various alcohols, clean reaction, production of no hazardous waste, open air reaction conditions and high yields. The catalyst can be reused without the loss of significant catalytic activity. 相似文献
29.
New chiral organocatalysts are envisaged based on a pyrrolidine–pyridone conjugate and synthesized from commercially available proline employing standard protocols. These catalysts were found to be useful for asymmetric Michael additions of ketones to nitroolefins to afford the desired products in very good yields (up to 98%) with excellent diastereo- and enantioselectivities (>97:3 syn/anti and up to 98% ee) in very short reaction time compared with the existing reports. 相似文献
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