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51.
52.
Laboratory formation of four isomers of C5H2 molecule is reported and detection of the ring-chain isomer (isomer 1) of C5H2 in cosmic objects has been suggested. For identification of a molecule in cosmic objects, one of the required input data
is EinsteinA-coefficients (radiative transition probabilities) for the molecule. Here, we report EinsteinA-coefficients for electric dipole transitions in the ring-chain isomer of C5H2 among the rotational levels of the ground electronic and ground vibrational states up to 21 cm−1. 相似文献
53.
Zhao T Shinde SR Ogale SB Zheng H Venkatesan T Ramesh R Das Sarma S 《Physical review letters》2005,94(12):126601
An external electric field induced reversible modulation of a room temperature magnetic moment and coercive field is achieved in an epitaxial and insulating thin film of dilutely cobalt-doped anatase TiO2. This first demonstration of an electric field effect in any oxide-based diluted ferromagnet is realized in a high quality epitaxial heterostructure of PbZr(0.2)Ti(0.8)O(3)/Co: TiO(2)/SrRuO(3) grown on (001) LaAlO3. The observed effect, which is about 15% in strength in a given heterostructure, can be modulated over several cycles. Possible mechanisms for electric field induced modulation of insulating ferromagnetism are discussed. 相似文献
54.
JPC – Journal of Planar Chromatography – Modern TLC - Sensitive and selective detection of monocrotophos after TLC is possible by use of vanillin as reagent. The product from alkaline... 相似文献
55.
In real catalyst systems, it is difficult to establish a correlation between catalytic properties and the shape (crystal planes, corners and steps) of the active catalytic particles. In this paper we present a clear shape dependence of the catalytic properties of a Vulcan‐supported fuel cell catalyst having 4 nm cubo‐octahedral platinum(0) nanocrystallites with (111) and (100) surfaces stabilized by sodium polyacrylate. The electrode materials were characterized by CO‐stripping cyclic voltammetry and transmission electron microscopy (TEM), showing that no agglomeration had occurred among the nanoparticles on the catalyst surfaces. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
56.
JPC – Journal of Planar Chromatography – Modern TLC - Cypermethrin is frequently encountered in poisoning cases in India. In TLC, the compound can be detected by spraying the plate with... 相似文献
57.
Catalyst-free alcoholytic deprotection of borane-protected phosphorus compounds offers a smooth, efficient, and clean alternative to existing deprotection methods. In this paper we report our results on the general applicability of deprotecting phosphane- and phosphite-borane adducts by means of simple alcoholysis without the use of molecular sieves as a catalyst. Phosphane-boranes bearing at least one aromatic substituent are readily deprotected in high yields. Borane complexes of trialkylphosphanes or phosphites, however, cannot be deprotected in this way. The main merit of our method is its simplicity: apart from evaporation of the solvent, no further work-up or purification is needed. 相似文献
58.
R. Nageswara Rao R. Mastan Vali Dhananjay D. Shinde 《Biomedical chromatography : BMC》2009,23(11):1145-1150
A highly sensitive and selective on‐line two‐dimensional reversed‐phase liquid chromatography/electrospray ionization–tandem mass spectrometry (2D‐LC‐ESI/MS/MS) method was developed and validated to determine rifaximin in rat serum by direct injection. The 2D‐LC‐ESI/MS/MS system consisted of a restricted access media column for trapping proteins as the first dimension and a Waters C18 column as second dimension using 0.1% aqueous acetic acid:acetonitrile as mobile phase in a gradient elution mode. Rifampacin was used as an internal standard. The linear dynamic range was 0.5–10 ng/mL (r2 > 0.998). Acceptable precision and accuracy were obtained over the calibration range. The assay was successfully used in analysis of rat serum to support pharmacokinetic studies. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
59.
60.
Jaiprakash N. Sangshetti Nagnnath D. Kokare Sandeep A. Kotharkar Devanand B. Shinde 《Monatshefte für Chemie / Chemical Monthly》2008,139(2):125-127
Summary. 2,4,5-Triaryl-1H-imidazoles were efficiently synthesized from benzoin or benzil, ammonium acetate, and aromatic or heteroaromatic aldehydes
in the presence of sodium bisulfite as catalyst. The present protocol offers significant improvements for the synthesis of
2,4,5-triaryl-1H-imidazoles with regard to yield of products, simplicity in operation, and cheap catalyst. 相似文献