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71.
Determination of concentration of iodine in grass and cow milk by NAA methods using reactor neutrons
P. V. Geetha N. Karunakara Ujwal Prabhu P. M. Ravi J. Sudhakar Nicy Ajith K. K. Swain R. Acharya A. V. R. Reddy 《Journal of Radioanalytical and Nuclear Chemistry》2012,294(3):435-438
Instrumental and preconcentration methods of neutron activation analysis (NAA) have been standardized for the determination of concentration of iodine in grass and cow milk samples, respectively. To study the transfer of iodine from grass to milk, known quantity of grass spiked with potassium iodide solution was fed to a cow. The spiked grass samples and milk samples, obtained from the cow after the ingestion of spiked grass, were collected. Iodine was separated from the milk samples chemically using Dowex 1X8 anion exchange resin. Spiked grass and ion exchange resin samples were neutron irradiated and radioactive assay was carried out using a 45?% relative efficiency HPGe detector coupled to an 8k channel analyzer. Iodine concentrations in spiked grass samples were found to be in the range of 1,487?C2,002?mg?kg?1. Concentration of iodine in milk after 12?h of feeding the cow with spiked grass was 871?±?56???g?L?1 which was reduced to 334?±?32???g?L?1 after 48?h. 相似文献
72.
The growth of single crystals of acetoacetanilide using slow evaporation technique is reported. Good-quality crystals up to a size of 20×10×1 mm3 are obtained. The grown crystals are characterized by employing UV-VIS spectrum, IR spectrum, and hardness measurements. Acetoacetanilide shows very good second-harmonic generation (SHG) efficiency. 相似文献
73.
Procedure for hydrothermal synthesis of ZSM-8-type zeolite crystals, using TEA—OH as a template, in the system having molar composition 16.2 (Na2O) — Al2O3 — 117 (SiO2) — 4.8 (TEA)2O — 3887 H2O at 170 °C is described. Results of characterization of these crystals by XRD, IR, EDAX, SEM, TGA, and adsorption studies are described and discussed. X-ray diffraction studies establish that the crystals are ZSM-8-type with structure similar to that of ZSM-5-type crystals. Crystals have prismatic bipyramidal morphology with average size 18–25 microns. Degased calcined samples adsorb xylenes in the order p > m > 0. Pore length per unit cell, estimated from n-hexane adsorption studies, is 46 Å. 相似文献
74.
K.M. Prabhu Kumar B.C. Vasantha Kumar P. Raghavendra Kumar Ray J. Butcher H.K. Vivek P.A. Suchetan H.D. Revanasiddappa Sabine Foro 《应用有机金属化学》2020,34(6):e5634
A novel selenated Schiff base (S) -L 1 H has been synthesized from (2S)-1-(benzylselanyl)-3-phenylpropan-2-amine which upon reduction formed a reduced Schiff base (S) -L 2 H . Palladium (II) complexes (S) -1 and (S) -2 of ligands (S) -L 1 H and (S) -L 2 H respectively were successfully synthesized. The structures of all four compounds were thoroughly identified by analytical and various spectroscopic techniques. The absolute molecular structures of the above two complexes were further confirmed by single crystal X-ray diffraction. Both (S) -L 1 H and (S) -L 2 H coordinated as monobasic ((S) -L 1–2 ), chelating, tridentate (Se,N,O−) ligands resulting in the complexes of composition (S) - [PdCl( L 1/2 )] [(S) -1/2 ]. In the crystals of complexes (S) -1 and (S) -2 , there were moderate to strong Se⋯O, CH⋯Cl and CH⋯O types of intermolecular secondary interactions. CT-DNA binding activity of these selenium-containing ligands and their palladium complexes bearing a Pd–Se bond have been evaluated for the first time by performing electronic absorption titration and fluorescence emission quenching using CT-DNA-EB and viscometric experiments. These ligands and complexes exhibited remarkable DNA binding activity as shown by their intrinsic DNA binding constants (Kb) and Stern–Volmer constants (Ksv) in the ranges 5.2–9.9 × 104 and 3.6–4.7 × 104, respectively. The viscosity of CT-DNA decreases with increasing concentration of these compounds. The results of the DNA-binding studies revealed that all of the compounds interact with DNA at a minor groove which was further confirmed by molecular docking studies. 相似文献
75.
Applied Biochemistry and Biotechnology - Studies on osmolyte-induced effects on proteins help in enhancing protein stability under stressed conditions for various applications. Using mixtures of... 相似文献
76.
We study a PH/G/1 queue in which the arrival process and the service times depend on the state of an underlying Markov chain J(t) on a countable state spaceE. We derive the busy period process, waiting time and idle time of this queueing system. We also study the Markov modulated EK/G/1 queueing system as a special case. 相似文献
77.
Large sample inference from single server queues 总被引:1,自引:0,他引:1
Problems of large sample estimation and tests for the parameters in a single server queue are discussed. The service time and the interarrivai time densities are assumed to belong to (positive) exponential families. The queueing system is observed over a continuous time interval (0,T] whereT is determined by a suitable stopping rule. The limit distributions of the estimates are obtained in a unified setting, and without imposing the ergodicity condition on the queue length process. Generalized linear models, in particular, log-linear models are considered when several independent queues are observed. The mean service times and the mean interarrival times after appropriate transformations are assumed to satisfy a linear model involving unknown parameters of interest, and known covariates. These models enhance the scope and the usefulness of the standard queueing systems.Partially supported by the U. S. Army Research Office through the Mathematical Sciences Institute of Cornell University. 相似文献
78.
The polarographic behavior of uranium(VI)-succinate complexes was studied in 0.5M NaClO4 medium at 30°C at a dropping mercury electrode. It was found that only the doubly charged succinate ion formed the complexes stable enough to be detected. The experimental evidence for this is discussed. The stability constant of uranium(V) (succinate)2 complex was evaluated. 相似文献
79.
A series of commercial organotin compounds was screened for efficacy against the three insect species Dysdercus cingulatus (cotton stainer), Anophelese stephensi (mosquito) and Musca domestica (house fly). Tributyltin species in the general order Bu3SnCl>(Bu3Sn)2O>Bu3Sn(linoleate) were more effective than two triphenyltin compounds. Tricyclohexyltin hydroxide, dimethyltin chloride, phenyltin trichloride and a diethyltin dichloridephenanthroline adduct were less effective. 相似文献
80.
The reaction of 1,2-bis(trifluoroacetyl)benzene (II) with ammonia, hydrazine, hydroxylamine and L-alanine has been investigated and the resulting heterocyclic compounds fully characterized on the basis of spectral data. The reaction of II with -aminophenol and -phenylenediamine led to the formation of tetracyclic compounds XI and XII respectively. The structure of compound XII has been further supported by single crystal X-ray crystallography. Our studies reveal the potential of the diketone II as a valuable synthon for the synthesis of a variety of heterocyclic systems with trifluoromethyl substituents. 相似文献