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101.
Rajesh Das 《Applied Surface Science》2007,253(14):6068-6073
Sn doped In2O3 films are deposited by rf-magnetron sputtering at 300 °C under Ar, Ar + O2 and Ar + H2 gas ambients. For the film prepared under argon ambient, electrical resistivity 6.5 × 10−4 Ω cm and 95% optical transmission in the visible region have been achieved optimizing the power and chamber pressure during the film deposition. X-ray diffraction spectra of the ITO film reveal (2 2 2) and (4 0 0) crystallographic planes of In2O3. With the introduction of 1.33% oxygen in argon, (2 2 2) peak of In2O3 decreases and resistivity increases for the deposited film. With further increase of oxygen in the sputtering gas mixture crystallinity in the film deteriorates and both the peaks disappeared. On the other hand, when 1.33% hydrogen is mixed with argon, the resistivity of the deposited film decreases to 5.5 × 10−4 Ω cm and the crystallinity remains almost unchanged. In case of reactive sputtering, the deposition rate is lower compared to that in case of non-reactive sputtering. HRTEM and first Fourier patterns show the highly crystalline structure of the samples deposited under Ar and Ar + H2 ambients. Crystallinity of the film becomes lower with the introduction of oxygen in argon but refractive index increases from 1.86 to 1.9. The surface morphology of the ITO films have been studied by high resolution scanning electron microscopy. 相似文献
102.
Rajesh Kharab Pardeep Singh Ravinder Kumar 《中国物理快报》2007,24(3):656-659
We investigate the effects of higher order multipole transitions, in particular electric quadrupole (E2) and El-E2 interference, on the Coulomb dissociation of 19 C within the framework of the first order eikonal approximation. The sensitivity of the total Coulomb breakup cross section and the longitudinal momentum distribution of the core fragment to these effects are checked. The breakup occurs predominately through the dipole transition and the contribution of E2 transition to the total cross section is found to be within the range from 1 to 3% of that of El. It is further observed that the El-E2 interference term contributes nothing to the integrated cross section. On the other hand, the longitudinal momentum distribution is observed to be insensitive to the E2 transition while the El-E2 interference introduces a small asymmetry in its shape. 相似文献
103.
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105.
A concise and practical strategy to obtain C3 reverse-prenylated pyrrolidinoindoline scaffold has been executed in 28.8% overall yield. The key conjugative step involved a Booker-Milburn-Feudoloff reaction involving an NCS-mediated activation of indole, followed by coupling to C5 dimethylallylalcohol. This linchpin step proceeded in 74% yield. The overall sequence proceeded in five steps from commercially available N-methyltryptamine with a single protection-deprotection operation and a single redox manipulation. Mechanistic insights of NCS activation, and an ensuing rearrangement of the isoprene unit were gained by rationally varying the C3 substituent. 相似文献
106.
Raju Suresh Kumar Stephen Michael Rajesh Subbu Perumal Perumal Yogeeswari Dharmarajan Sriram 《Tetrahedron: Asymmetry》2010,21(11-12):1315-1327
Enantiomerically pure (R)-(1-phenylethyl)-3,5-bis[(E)-arylmethylidene]tetrahydro-4(1H)-pyridinones were synthesized for the first time, and their 1,3-dipolar cycloaddition with nitrile oxides affording di- and trispiroheterocycles regio- and stereoselectively in moderate yields was investigated. These compounds were evaluated against Mycobacterium tuberculosis H37Rv (MTB) and multi-drug-resistant M. tuberculosis (MDR-TB). Among the compounds screened, the dispiroheterocycle, namely, (5R,6R,10S)-3,9-bis(4-chlorophenyl)-10-(2,4-dichlorophenyl)-14-[(E)-(2,4-dichlorophenyl)methylidene]-12-[(R)-1-phenylethyl]-1,4,7-trioxa-2,8,12-tri-azadispiro[4.0.4.4]tetradeca-2,8-diene 5m was found to possess the maximum activity with MIC of 0.49 μM against MTB, being 9.6 and 15.6 times more potent than ciprofloxacin and ethambutol, respectively. Against MDR-TB, 5m displayed maximum activity with an MIC of 0.49 μM, with it thus being more active than rifampicin, isoniazid, ciprofloxacin and ethambutol by 7.8, 23, 77 and 124 times, respectively. 相似文献
107.
Rajesh S. Kulkarni 《Proceedings of the American Mathematical Society》2008,136(10):3375-3382
In this note, we show that down-up algebras at roots of unity are maximal orders over their centers.
108.
109.
An operationally simple and high yielding procedure has been developed for the preparation of nitriles from aldoximes and primary amides using bromodimethylsulfonium bromide (BDMS) as a novel and efficient reagent in the absence of any added base or catalyst. The optimal protocol is applicable to access a wide range of cyano compounds including aromatic, heterocyclic, and aliphatic species. The conversion of aldoximes to nitriles takes place at room temperature in acetonitrile, whereas acetonitrile at reflux temperature is required for rapid conversion in the case of primary amides. 相似文献
110.
Umakanta Tripathy R. Justin Rajesh Prem B. Bisht A. Subrahamanyam 《Journal of Chemical Sciences》2002,114(6):557-564
The excited state absorption cross-section of 5,5′-dichloro-11-diphenyl-amino-3,3′-diethyl-10, 12-ethylinethiatricarbocyanine
perchlorate (IR140) have been measured by using a single beam transmission technique. Z-scan experiments have been used to find out a few nonlinear
parameters. The excited state relaxation times have also been measured by using laser induced transient grating (LITG) technique. 相似文献