Vineeta Singh

Properties of sol-gel derived YAG:Eu3+ hierarchical nanostructures with their time evolution studies

Eu3+ doped yttrium aluminum garnet (YAG) nanoparticles were synthesized by sol-gel method. The samples were characterized by x-ray diffraction (XRD), transmission electron microscopy (TEM), and photoluminescence (PL) spectroscopy including vacuum ultraviolet (VUV) PL spectroscopy. XRD confirmed that each and every phases of YAG were present, indicating very good quality of sample. The crystallite size, estimated by XRD, increased from 10 to 30 nm with annealing temperatures and significant changes in morphology with annealing temperature was also found in TEM study. The particles were in spherical shape initially but agglomeration of particles started at higher temperatures resulting in hierarchical nanostructures having dimension more than 50 nm. The annealed YAG:Eu3+ hierarchical nanostructures showed strong red luminescence under VUV excitation, corresponding to D50→F72 transition. PL spectra also showed significant increase in luminescence intensity with the increase in annealing temperature. Time evo...

The effect of actinomycin D on the insulin-mediated enhancement of incorporation of 14C-labeled precursors into protein and RNA by fetal RAT thyroid glands in organ culture

Abstract Insulin enhanced the incorporation of 14 C of uniformly labeled leucine into proteins and of [8- 14 C]adenine into RNA of fetal rat thyroid glands in organ culture. Actinomycin D suppressed the formation of protein by about 65 % and of RNA by about 90 %. The influence of insulin on 14 C incorporation into protein persisted even in the presence of actinomycin D. This indicates that insulin-mediated enhancement of protein formation by the embryonic rat thyroid gland may not be dependent entirely on the increased formation of messenger RNA.

Variability in Phytophthora drechsleri f. sp. cajani and Effect of Temperature

The present experiment was undertaken to study the cultural, morphological and pathological variation in six isolates of Phytophthora cajani. The isolates were collected from pigeonpea growing areas of eastern Uttar Pradesh. Isolates exhibited considerable variations in cultural characters and growth on potato dextrose agar medium. The universal ITS1 and ITS4 primers showed the difference among P. cajani isolates. There was significance influence of temperature on the growth of isolates, however isolates could not be differentiated based on the temperature. The average growth (1.69 cm2) at 30°C temperature was recorded with all the isolates followed by average growth (1.25 cm2) at 35°C temperature. The maximum radial growth (3.6 cm2) was observed at 96 h in isolate PDC015-1. The isolate PDC013-1 and PDC0143 showed highest 47.0% plant mortality on ICP 7119 genotype. Among the isolates PDC014-3 killed 28.6% plants after 4th day of inoculation.