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11.
The axial aqua bound copper(II) complex [Cu(dpq)2(H2O)](ClO4)2, having a planar NN-donor heterocyclic base dipyridoquinoxaline (dpq) as the DNA minor groove binder, shows efficient hydrolytic cleavage of supercoiled DNA in the dark and in the absence of any external reagents, as evidenced from T4 ligase experiments, with a rate of 5.58 +/- 0.4 h(-1) and a rate enhancement of 1.55 x 10(8). 相似文献
12.
The analysis of dehydration of the complexes, [La(C8H8NO3)3.2H2O] and [Yb(C8H8NO3)3.3H2O] for the evaluation of kinetic parameters (Z, E &S
*) and mechanism of dehydration by non-isothermal methods are reported. The complexes decompose in three well defined steps involving random nucleation mechanism. First two steps involving the dehydration and the third step the loss of the ligand moiety. The intermediates formed during decomposition were found to be unstable for carrying out any significant studies.
Zusammenfassung Zwecks Ermittlung der kinetischen Parameter (Z, E undS *) und des Mechanismus der Dehydratierung durch nichtisotherme Verfahren wird die Analyse der Dehydratierung der Komplexe [La(C8H8NO3)3·2H2O] und [Yb(C8H8NO3)3·3H2O] beschrieben. Die Komplexe zersetzen sich in drei gut definierten Schritten mit Random-Keimbildungsmechanismus. Die ersten zwei Schritte beinhalten die Dehydratierung, der dritte Schritt den Verlust der Liganden. Die wÄhrend der Zersetzung entstandenen Zwischenprodukte erwiesen sich für jegliche signifikante Untersuchung als zu unstabil.相似文献
13.
14.
Induced twisted-grain-boundary phases in the binary mixtures of a cholesteric and a nematic compound
Thermodynamical, optical-texture and dielectric studies have been performed to study the phase diagram of the binary system of 5-cholesten-3β-ol-octanoate and 4-n-nonyloxybenzoic acid. It is observed that low concentrations of 5-cholesten-3β-ol-octanoate (2–30?mol?%) in 4-n-nonyloxybenzoic acid induce a mean-field phase diagram derived by Renn within the framework of the chiral Chen–Lubenski model. Various optical textures of the twisted-grain-boundary (TGB) phases under different conditions of molecular anchoring have been observed. Weak transitions related to the TGB phases have been detected by temperature dependent dielectric spectroscopy. 相似文献
15.
16.
A. Mondal N. K. Singh P. Chinnamuthu J. C. Dhar T. D. Das P. K. Bose 《Applied Physics A: Materials Science & Processing》2013,110(2):479-485
Glancing angle deposition (GLAD) has been employed to fabricate the Si/Si–O nanowires (NWs). The perpendicular NW on silicon substrate shows the amorphous nature. The visible light emission from the NWs was observed from the Si/Si–O nanoparticles. High light absorption inside the Si/Si–O NW structure was recorded. 相似文献
17.
Chlorosulfonyl isocyanata (CSI) reacts with 2H-azirines 1 a-c at -78°C to form [2+2+2] cycloadducts 3a-c and 4a-c. The tricyclic aziridine derivatives 4a-c undergo CSI extrusion reactions and subsequent oxidation to the corresponding pyrazines 5a-c. Structural identifications of 3a-c and 4a-c are based on ir, nmr and mass spectral data. 相似文献
18.
Shashank Tripathi Achu Chandran Tilak Joshi Anil Kumar Ajay Dhar 《Liquid crystals》2013,40(9):1255-1262
In this article, a newly synthesised ferroelectric liquid crystal (FLC) material, namely LAHS 22, has been characterised. The characterisation of the FLC material has been performed using dielectric relaxation spectroscopy, differential scanning calorimetry and polarisation optical microscopy. We observed an enhancement in the dielectric and electro-optical properties of the FLC material by incorporating gold nanoparticles (GNPs)-decorated multiwalled carbon nanotubes (MWCNTs). The GNPs-decorated MWCNTs cause an increment in dielectric dispersion (up to kHz), absorption, spontaneous polarisation and rotational viscosity of the FLC material. The pure and GNPs-decorated MWCNTs doped FLC cells were analysed by means of various dielectric spectroscopic and optical measurements. The observed enhancement in the dielectric and electro-optical properties of the FLC material has also been studied with concentration of GNPs-decorated MWCNTs in FLC material. The GNPs-decorated MWCNTs/FLC composites are not only of fundamental importance, but also useful materials for device applications such as liquid crystal displays and memory devices. 相似文献
19.
N-Sulfonyl imines have been synthesized in good to excellent yields from aldehydes and chloramine-T using proline as an organocatalyst in aqueous medium at ambient temperature. The protocol is applicable to a wide range of aldehydes, especially enals exhibit remarkable efficiency in the reaction. The reaction presumably occurs via iminium activation and opens new avenues for the synthesis of N-sulfonyl imines under environmentally benign and mild conditions. 相似文献
20.
A novel and practical access to symmetrical and unsymmetrical 2,5-disubstituted 1,3,4-oxadiazoles directly from aldehydes and acylhydrazides using visible light irradiation under an air atmosphere in the presence of eosin Y as an organophotoredox catalyst at rt is reported. This is the first example of oxidative cyclization of acylhydrazones employing air and visible light as inexpensive, readily available, non-toxic, and sustainable reagents. 相似文献