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21.
The reaction of 1,3,4-oxathiazol-2-one derivative with 2-arylidene-1,3-indandione to furnish novel spiroindene-1,3-dione isothiazoline derivatives by Michael/1,3-dipolar [3+2]-cycloaddition reaction was investigated. The key 1,3-dipolar cycloaddition reaction step was examined in toluene solvent at reflux temperature to obtain mixture of two regioisomers (6a and 6b – 14a and 14b) and single isomers (1520). The scope of this new reaction was demonstrated with many examples with high reactivity and yields.  相似文献   
22.
Russian Journal of General Chemistry - A thiophene contained imidazo phenanthroline ligand TIP {TIP = 2-(thiophen-2-yl)-1H-imidazo-[4,5-f][1,10]phenanthroline{ and its mononuclear Ru(II)...  相似文献   
23.
Cellulose/silver nanoparticle composite films with in situ-generated silver nanoparticles (AgNPs) were prepared using Ocimum sanctum leaf extract as a reducing agent in the absence and presence of sunlight and were characterized by SEM, FTIR, XRD, and antibacterial tests. Sunlight hastened up the preparation of these composite films. The average size of the in situ-generated AgNPs was reduced by the sunlight. The antibacterial activity and other properties of the composites were enhanced by the sunlight. The cellulose/AgNP composite films with improved properties by sunlight can be considered for medical purpose as antibacterial dressing materials.  相似文献   
24.
    
Kinetics of the bis(2,2,6,2-terpyridine) iron(II)-cobalt(III) electron transfer reaction in sulfuric acid medium has been studied using stopped-flow spectrophotometry. The reaction is first order both in substrate and oxidant. Hydrogen ions accelerate the reaction, whereas bisulfate ions retard. A suitable mechanism is proposed considering Co3+, CoSO 4 + and Co(SO4) 2 as the reactive oxidizing species.
(2,2,6,2-)(II)(III) . , , . , -. , Co3+, CoSO4 + Co(SO4)2 .
  相似文献   
25.
A study has been made on the oxidation of bis(2,2,6, 2-terpyridine)-iron(II), Fe(tpy) 2 2+ by manganese (IV) using stopped-flow spectrophotometry in H2SO4–H3PO4 mixtures. The reaction is first order in each the substrate and the oxidant. The rate of the reaction increases with hydrogen ion concentration. A plausible mechanism is proposed considering the protonated forms of manganese(IV) as reactive oxidizing species. The reaction obeys the rate law
  相似文献   
26.
Recently, we introduced a class of generalized hypergeometric functionsI n:(b q)/α:(a p) (x, w) by using a difference operator Δ x,w , where . In this paper an attempt has been made to obtain some bilateral generating relations associated withI n ga (x, w). Each result is followed by its applications to the classical orthogonal polynomials.  相似文献   
27.
Journal of Optimization Theory and Applications - A framework for monitoring a target modeled as Dubins car using multiple UAVs is proposed. The UAVs are subject to minimum and maximum speed,...  相似文献   
28.
In the present investigation, the recently developed, simple, robust, and powerful metaheuristic symbiotic organism search (SOS) algorithm was used for simulation of J-V characteristics and optimizing the internal parameters of the dye-sensitized solar cells (DSSCs) fabricated using electrospun 1-D mesoporous TiO2 nanofibers as photoanode. The efficiency (η =?5.80%) of the DSSC made up of TiO2 nanofibers as photoanode is found to be ~ 21.59% higher compared to the efficiency (η =?4.77%) of the DSSC made up of TiO2 nanoparticles as photoanode. The observed high efficiency can be attributed to high dye loading as well as high electron transport in the mesoporous 1-D TiO2 nanofibers. Further, the validity and advantage of SOS algorithm are verified by simulating J-V characteristics of DSSC with Lambert-W function.  相似文献   
29.
A new ligand 3-(1H-imidazo[4,5-f][1,10]phenanthrolin-2yl)phenylboronic acid and its (IPPBA) three ruthenium(II) complexes [Ru(phen)2(IPPBA)](ClO4)2 (1), [Ru(bpy)2(IPPBA)](ClO4)2 (2) and [Ru(dmb)2(IPPBA)](ClO4)2 (3) have been synthesized and characterized by elemental analysis, UV/VIS, IR, 1H-NMR,13C-NMR and mass spectra. The binding behaviors of the three complexes to calf thymus DNA were investigated by absorption spectra, emission spectroscopy, viscosity measurements, thermal denaturation and photoactivated cleavage. The DNA-binding constants for complexes 1, 2 and 3 have been determined to be 7.9?×?105 M?1, 6.7?×?105 M?1 and 2.9?×?105 M?1. The results suggest that these complexes bound to double-stranded DNA in an intercalation mode. Upon irradiation at 365 nm, three ruthenium complexes were found to promote the cleavage of plasmid pBR322 DNA from super coiled form ? to nicked form ??. Further in the presence of Co2+, the emission of DNA–Ru(ΙΙ) complexes can be quenched. And when EDTA was added, the emission was recovered. The experimental results show that all three complexes exhibited the “on–off–on” properties of molecular “light switch”. The highest Cytotoxicity potential of the complex1 was observed on the Human alveolar adenocarcinoma (A549) cell line. Good agreement was generally found between the spectroscopic techniques and molecular docked model which provides further evidence of groove binding.  相似文献   
30.
Synthesis of 1-benzyl-3-methyl (I), 1-beazyl-3-substituted benzyl (II) and 1-methyl-3-substituted benzyl (III)-2-aryl benzimidazolines is described. (I) acc obtained by the condensation of N1benzyl-N2methyl-o-phenylenediamine with various aldehydes in metharol. Compounds (II) are prepared from N1-benzyl-N2-arylidene-o-phenylenediamines in acetic acid, through a process of disproportionation involving an oxidation-reduction process. Likewise, (III) are obtained from N1-methyl-N2-arylidenc-o-phenylenediamines. The exact structure of N1-benzyl-N2-arylidene-o-phenylenediamines which can exist in the open chain form or in the ring form has been investigated using nmr spectroscopy.  相似文献   
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