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51.
P. K. Roychowdhuary Sangeeta Mehrotra Sugandh Srivastava K. K. Upadhay Rakesh K. Mishra Ajit Kumar Shalini Upadhyay 《Journal of heterocyclic chemistry》2008,45(3):741-744
A series of 4‐thiazolidinones having triazinethione moieties have been synthesized by the systematic chemical modification of S‐benzylmercapto‐1‐aryl‐4‐(4‐methoxyphenyl)‐1,6‐dihydro‐1,3,5‐triazine‐6‐thione. 相似文献
52.
A new route for the synthesis of linear and vinyl thioethers has been demonstrated using bare silica nanoparticle as catalyst at room temperature under solvent-free conditions. The catalyst can be reused up to six times without loss of catalytic activity. 相似文献
53.
Akhil R Chakravarty Pattubala A. N. Anreddy Bidyut K. Santra Anitha M. Thomas 《Journal of Chemical Sciences》2002,114(4):391-401
Redox active mononuclear and binuclear copper(II) complexes have been prepared and structurally characterized. The complexes have planar N-donor heterocyclic bases like 1,10-phenanthroline
(phen), dipyridoquinoxaline (dpq) and dipyridophenazine (dppz) ligands that are suitable for intercalation to B-DNA. Complexes
studied for nuclease activity have the formulations [Cu(dpq)2(H2O)] (ClO4)2.H2O (1), [CuL(H2O)2(μ-ox)](ClO4)2 (L = bpy,2; phen,3; dpq,4; and dppz,5) and [Cu(L)(salgly)] (L = bpy,6; phen,7; dpq,8; and dppz,9), where salgly is a tridentate Schiff base obtained from the condensation of glycine and salicylaldehyde. The dpq complexes
are efficient DNA binding and cleavage active species. The dppz complexes show good binding ability but poor nuclease activity.
The cleavage activity of thebis-dpq complex is significantly higher than thebis-phen complex of copper(II). The nuclease activity is found to be dependent on the intercalating nature of the complex and
on the redox potential of the copper(II)/copper(I) couple. The ancillary ligand plays a significant role in binding and cleavage
activity. 相似文献
54.
Sangeeta Rawal 《Macromolecular Symposia》2024,413(1):2300096
This overview looks critically at the present prospects and future challenges in development of polyethyl methacrylate (PEMA) and its composites. It is shown herein to be a promising candidate for various applications, including energy storage, textile, electronics, biomedical, packaging, coatings and adhesives, etc. Due to its high ionic conductivity, thermal stability, and low cost of synthesis, PEMA is also used as a solid electrolyte in supercapacitors. This polymer has the ability to transport ions efficiently between the two electrodes of the supercapacitor, thereby leading to improved performance and efficiency. Additionally, PEMA can withstand high temperatures without breaking down, thus making it suitable for a range of applications. Further, it is shown due to its unique properties and versatility, PEMA has significant potential for a range of biomedical applications. This review of existing literature strongly suggests that the use of PEMA as a solid electrolyte in supercapacitors can be of significant potential for advancing energy storage technology. It also warrants further research to optimize its use in many other challenging practical applications. 相似文献
55.
Ramil F. Fatykhov Igor A. Khalymbadzha Ainur D. Sharapov Anastasia P. Potapova Nataliya N. Mochulskaya Anton N. Tsmokalyuk Alexandra V. Ivoilova Polina N. Mozharovskaia Sougata Santra Oleg N. Chupakhin 《Molecules (Basel, Switzerland)》2022,27(20)
A different type of MnO2-induced oxidative cyclization of dihydrotriazines has been developed. These dihydrotriazines are considered as a “formal” Schiff’s base. This method provided easy access to naphthofuro-fused triazine via the C-C/C-O oxidative coupling reaction. The reaction sequence comprised the nucleophilic addition of 2-naphthol or phenol to 1,2,4-triazine, followed by oxidative cyclization. The scope and limitations of this novel coupling reaction have been investigated. Further application of the synthesized compound has been demonstrated by synthesizing carbazole-substituted benzofuro-fused triazines. The scalability of the reaction was demonstrated at a 40 mmol load. The mechanistic study strongly suggests that this reaction proceeds through the formation of an O-coordinated manganese complex. 相似文献
56.
RF SQUID behaviour has been observed at 77 K in YBaCuO thick films prepared by screen printing technique. A hole shunted with
a microbridge type of geometry is patterned manually for observing rf SQUID behaviour. Flux noise spectrum is also studied
and it is found to depend on the quality of the film. The spectral density of the flux noise in the white noise region is
1.7×10−3 Φ0/√Hz at 77 K. 相似文献
57.
B. S. Dandapat Bidyut Santra S. K. Singh 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2010,46(2):685-695
A thin viscous liquid film flow is developed over a stretching sheet under different non-linear stretching velocities in presence
of uniform transverse magnetic field. Evolution equation for the film thickness is derived using long-wave approximation of
thin liquid film and is solved numerically by using the Newton–Kantorovich method. It is observed that all types of stretching
produces film thinning, but non-monotonic stretching produces faster thinning at small distance from the origin. Effect of
the transverse magnetic field is to slow down the film thinning process. Observed flow behavior is explained physically. 相似文献
58.
In order to estimate the damage densities produced by γ-rays to Makrofol-N and Makrofol-KG, some structural, optical and etching studies have been performed. It is found that both polymers are insensitive to low γ-doses (up to 103 krad) but are influenced at higher doses. The changes in etching parameters have been noticed along with the changes in the FTIR and UV–VIS spectra. The results have been discussed on the basis of some basic mechanisms of radiation interactions with organic materials. 相似文献
59.
The influence of the presence of BaO impurity on the optical absorption, radiation hardness and thermally stimulated luminescence of BaF2 has been investigated. The presence of oxygen impurity gives rise to three absorption bands in the UV region, peaking around 220, 280 and 335 nm. Further, the impurity is found to be detrimental to crystal hardness against ionizing radiations. The thermally stimulated luminescence (TSL) has been studied from gamma-irradiated crystals containing different fractions of BaO impurity. Four prominent glow peaks around 100°C (peak I), 150°C (peak II), 220°C (peak III) and 290°C (peak IV) are observed for crystals containing BaO impurity concentrations lower than 0.5% (by wt). For crystals containing higher impurity concentrations, two additional peaks around 75°C and 260°C are also observed. The kinetics of TSL emission is observed to be of first order, implying that the absorption and the emission centers responsible for TSL are the same. The normalized TSL output for peak I is found to vary linearly with the concentration of oxide impurity. This fact can be utilized to detect the presence of minute amounts of oxygen in BaF2 lattice, which is crucial to the growth of crystals exhibiting high radiation hardness. 相似文献
60.
Lobana Tarlok S. Paul Seema Hundal Geeta Obrai Sangeeta 《Transition Metal Chemistry》1999,24(2):202-205
Reaction of 1-hydroxypyridine-2-thione (HpyOS) in CHCl3 with Ag2CO3 suspended in CHCl3 under magnetic stirring followed by addition of PPh3 yields a product of stoichiometry: Ag(pyOS)(PPh3). The compound adopts a dimeric structure [Ag(pyOS)(PPh3)]2 (1) where each Ag atom acquires a distorted tetrahedral geometry by co-ordinating to one oxygen, two sulphur and one phosphorus atoms. The Ag2S2 core forms a parallelogram [Ag—S 2.507(1), 2.822(1)Å] with Ag—S—Ag and S—Ag—S angles of 74.8(1) and 105.2(1)°, respectively. 相似文献