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121.
The analytical performance of a new type of fluorescence detector, based on a transversely illuminated liquid core waveguide (LCW), has been investigated using the determination of NH(3)/NH(4)(+) as the 1-sulfonatoisoindole. With a very inexpensive combination of a miniature Hg blacklight as an excitation source, a colored plastic sheet as the emission filter, and an integrated blue sensitized photodiode-operational amplifier as the detector (totaling <$100 in hardware cost), we were able to achieve a limit of detection (LOD) of 35 nM (1.6 pmol) NH(3) with a linear dynamic range up to 60 muM NH(3). Details of detector construction and performance are given. 相似文献
122.
123.
Sengupta Arijit Deb Ashish Kumar Singha Gupta Nishesh Kumar Kumar Parveen Dasgupta Kinshuk Ali Sk. Musharaf 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(2):331-340
Journal of Radioanalytical and Nuclear Chemistry - Herein, sorption of pentavalent neptunium from aqueous acidic solution was carried out onto 1st and 2nd generation of poly(amidoamine) dendrimer... 相似文献
124.
125.
Sonali Sinha 《Pramana》1999,52(6):593-608
The chiral perturbation theory has been used to calculate pionic and radiative decays ofb-hadrons. These particles are being studied and their decays have been predicted. 相似文献
126.
Maddali L.N. Rao Varadhachari Venkatesh Priyabrata Dasgupta 《Tetrahedron letters》2010,51(38):4975-4980
Oxalyl chloride has been demonstrated to function as C1 carbonyl synthon in the carbonylations of triarylbismuth and triarylindium nucleophiles under palladium-catalyzed conditions. All the three aryl groups from both bismuth and indium reagents participated in carbonylative couplings to afford the corresponding functionalized ketones in high yields. This study also disclosed a novel utilization of oxalyl chloride as facile alternative source of CO for carbonylations under palladium catalysis. 相似文献
127.
Kerry-Ann Green Paul T. Maragh Kamaluddin Abdur-Rashid Alan J. Lough Tara P. Dasgupta 《Tetrahedron letters》2014
The synthesis of a series of imidazolinium chlorides containing the [2.2]paracyclophane scaffold is described. Attempts to deprotonate the salts with strong bases resulted in hydrolytic ring-opening and yielded N-formylethylenediamine products rather than the intended free carbenes. 相似文献
128.
129.
Photonic crystals fabricated from the colloidal spheres of polymethyl methacrylate (PMMA) using the inward-growing self-assembly
technique were subsequently in-filled with zinc oxide (ZnO) prepared by the sol-gel process. The polymer template was removed
by heat treatment and chemical method to get ZnO-inverse photonic crystal. The structural quality of the inverse photonic
crystal obtained by the chemical method was found to be superior to that obtained by heat treatment. The ZnO-inverse photonic
crystal obtained by the chemical method was further treated at an elevated temperature to ensure the crystalline nature of
ZnO. Laser-induced emission studies on ZnO-inverse photonic crystals were carried out at an excitation wavelength of 325 nm.
The emission spectra showing UV and visible bands at collection angle of 45° from the direction of excitation helped to establish
the role of crystalline ZnO. 相似文献
130.
A time-dependent, two-dimensional (in space) rate equation model of a transversely-pumped pulsed dye laser oscillator, which
incorporates transverse pump intensity variation in the presence of intracavity dye laser radiation, is proposed to understand
and predict its temporal behaviour. The model yields output pulses which agree well with experimental results using rhodamine
6G and kiton red dyes. The shape, amplitude and temporal position of the simulated pulse within the pump pulse vary dramatically
across the tuning range of each dye depending on the relative gain and loss values. 相似文献