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61.
The fluorescence spectra of uranyl complexes with pyridine are described and compared with the known spectra of double salts and addition compounds. In some cases the spectra are of the double salt type whereas in others of the type of addition compounds. The fluorescence spectra of uranyl salts have been generalised into three categories,viz., (i) single reversal and single banded fluorescence spectrum (to which most of the uranyl salts belong), (ii) double reversal and double banded spectrum (to which uranyl sulphate trihydrate belongs) and (iii) single reversal and double banded fluorescence spectrum (to which pyridine uranyl chloride form I belongs). This latter situation is also found in the case of uranium activated alkali fluoride phosphors. The decay times of these complexes are also reported. 相似文献
62.
Y B S R Prasad V K Senecha H C Pant M P Kamath G S Solanki P K Tripathi A P Kulkarni S Gupta R Pareek A S Joshi N Sreedhar Sameer Nigam C P Navathe 《Pramana》2000,55(5-6):797-802
The x-ray emission from slab targets of copper irradiated by Nd:glass laser (1.054 μm, 5 and 15 ns) at intensities between 1012 and 1011W/cm2 has been studied. The x-ray emissions were monitored with the help of high quantum efficiency x-ray silicon photo diodes
and vacuum photo diodes, all covered with aluminium filters of different thickness. The x-ray intensity vs the laser intensity
has a scaling factor of (1.2–1.92). The relative x-ray conversion efficiency follows an empirical relationship which is in
close agreement with the one reported by Babonneau et al. The ion velocities were monitored using Langmuir probes placed at different angles and radial distances from the target
position. The variation of the ion velocity with the laser intensity follows a scaling of the form Φ
β
where β ∼0.22 which is in good agreement with the reported scaling factor values. The results on the x-ray emission from Cu plasma
are reported. 相似文献
63.
An intense laser radiation (1012 to 1011 W/cm−2) focused on the solid target creates a hot (≥1 keV) and dense plasma having high ionization state. The multiple charged ions
with high current densities produced during laser matter interaction have potential application in accelerators as an ion
source. This paper presents generation and detection of highly stripped titanium ions (Ti) in laser produced plasma. An Nd:glass
laser (KAMETRON) delivering 50 J energy (λ=0.53 μm) in 2.5 ns was focused onto a titanium target to produce plasma. This plasma
was allowed to drift across a space of ∼3 m through a diagnostic hole in the focusing mirror before ions are finally detected
with the help of electrostatic ion analyzer. Maximum current density was detected for the charge states of +16 and +17 of
Ti ions for laser intensity of ∼1011 W/cm−2. 相似文献
64.
Journal of Fluorescence - The methyl orange [C14H14N3SO3Na], an azo dye exhibited strong emission and large Stokes shift in various solvents, and the largest shift (Δλ = 125.51nm or... 相似文献
65.
Abstract Experiments carried out demonstrate the production due tosoft X-rays of enhanced ablation pressure. The targets used were planar gold foils. Aluminium targets were also used to demonstrate the relative effect. 相似文献
66.
Moumita Roy Nabin Aryal Yifeng Zhang Sunil A. Patil Deepak Pant 《Current Opinion in Green and Sustainable Chemistry》2022
In order to achieve a carbon-efficient circular economy, a paradigm shift is required to valorize carbon dioxide (CO2) and organic wastes into value-added products. Among others, microbial electrosynthesis (MES) and electrofermentation (EF) technologies have shown the potential to contribute to the circular carbon economy. Besides carbon conversion, both technologies can be applied to store excess green energy in the form of valuable transportable chemicals. This article sheds light on the current status of MES and EF technologies by covering the most important literature from the last two years. Recent progress on reactor design and process optimization, scale-up attempts, and a summary of ongoing or completed technology-oriented research projects over the recent years are presented. Furthermore, the key challenges and future research perspectives desired to enable the implementation of the MES technology are also discussed. 相似文献
67.
H. J. Pant V. K. Sharma Gursharan Singh V. K. Raman J. Bornare R. R. Sonde 《Journal of Radioanalytical and Nuclear Chemistry》2012,294(1):59-63
A rotary fluidized bioreactor (RFBR) designed for treatment of wastewater was required to be investigated for its hydrodynamic behaviour and validation of design. A radiotracer investigation was carried out to measure residence time distribution (RTD) of wastewater in the RFBR using 82Br as a radiotracer. The radiotracer was instantaneously injected into the inlet feed line and monitored at the inlet and outlet of the reactor using collimated scintillation detectors connected to a data acquisition system. The measured RTD data was treated and simulated using a tanks-in-series model and model parameters i.e. number of tanks describing the degree of mixing was obtained. The results of the investigation showed no flow abnormalities and the reactor behaved as an ideal continuously stirred-tank reactor at all the operating conditions. Based on the results, the design of the reactor was validated. 相似文献
68.
Seema Pant Priyanka Sharma Umesh C. Pant 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2974-2983
Six 5-substituted-2-aminobenzenethiols have been reacted with 3-(2-chlorophenyl)-1-(4-chlorophenyl)-2-propenone and 3-(2-chlorophenyl)-1-(2-thienyl)-2-propenone in dry ethanol saturated with dry HCl gas, to obtain twelve new compounds, 8-substituted-2-(2-chlorophenyl)-4-(4-chlorophenyl/2-thienyl)-2,5-dihydro-1,5-benzothiazepines in satisfactory yields. The structures of the final products have been assigned by elemental microanalyses data for elements, C, H, and N and by IR, 1 H NMR, and mass spectroscopies. The synthesized compounds have been evaluated for their relative antimicrobial activity against the gram-positive bacteria, Staphylococcus aureus, gram-negative bacteria, Pseudomonas aeruginosa and the fungus, Candida albicans. The compounds have been found to show little antibacterial activity, but interestingly, showed significant antifungal activity. 相似文献
69.
T. Rajeshwari S. Rajesh B. R. Kerur S. Anilkumar Narayani Krishnan Amar D. Pant 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(1):61-65
The activity of the terrestrial primordial radionuclides 226Ra, 232Th and 40K are measured for Bidar soil samples. The collected soil samples are analyzed using HPGe detector based on high resolution gamma spectrometric system. The activity of the three radionuclides 226Ra, 232Th and 40K were found to be in the range of BDL–47.68, 7.65–59.08 and BDL–260.65 Bq kg?1 respectively. The mean gamma absorbed dose rate in air above 1 m from ground is estimated to be 34.47 nGy h?1. Annual effective dose equivalent and the radium equivalent activity were within the limits in the present study and it is found that the activity of the radionuclides are comparable with the worldwide literature values. Also the external hazard indices for the soil samples of Bidar district were within the limit of unity. 相似文献
70.
The nonlinear optical properties of coumarin 343 (C343) dye-attached TiO2 nanoparticles in the size range 5–8 nm adsorbed at the interface of water/1,2-dichloroethane have been studied by using the
surface second harmonic generation technique. No second harmonic (SH) response was observed from the bare TiO2 nanoparticles adsorbed at the interface, however, a strong SH response was measured from the dye molecules attached at the
surfaces of the nanoparticles. The increase in the SH intensity with the increase of TiO2 nanoparticle concentration in the aqueous solution of C343 is mainly due to the pre-alignment of the dye molecules at the
surfaces of nanoparticles and is partly due to the third-order polarization contribution of the nanoparticles to the observed
total SH response. 相似文献