41 research outputs found
3-(7,8,13,14-Tetrahydrodibenzo[a,i]phenanthridin-5-yl)benzene-1,2-diol
In the title compound, C27H21NO2, the half-chair conformation of the alicyclic rings gives rise to a slightly folded structure of the central tricyclic tetrahydrophenanthridine unit. Tandem intramolecular O—H⋯N and O—H⋯O hydrogen bonds give rise to adjacent S(6) and S(5) rings, respectively, which dictate the conformation of the 5-aryl substituent. In the crystal structure, an intermolecular C—H⋯O contact generates chains parallel to [101]. Short O—H⋯π and C—H⋯π contacts are also observed
A semi-synthetic chickpea flour based diet for long-term maintenance of laboratory culture of helicoverpa armigera
Artificial rearing of insects in the laboratory is a pre-requisite for undertaking studies on insecticide/
biopesticide bioassays, and evaluation of germplasm, segregating breeding material, mapping populations,
and transgenic plants for resistance to insects. For successful rearing of insects in the laboratory, there is
need for standardizing a semi-synthetic diet that supports survival and development of the insect for
several generations. We tested different semi-‘synthetic diets for rearing the legume pod borer, Helicoverpa
armigera for two generations under laboratory conditions. All the semi-synthetic diets tested supported
the growth and development of H. armigera up to adult emergence, but there were significant differences
in survival and development and fecundity on different diets. The highest larval survival was observed in
the wheatgerm based diet in first (97.5%) and second generation (93.5%), followed by chickpea based
modified diet (93.75% survival in both the generations). The lowest larval weights (270.7 and 283.7 mg)
were recorded in the tapioca granules diet in 1st and 2nd generation, respectively. The adult emergence
ranged from 68.7 to 83.3%, and 60.4 to 81.2% in the 1st and 2nd generation, respectively. Least fecundity
was observed in the tapioca granules based diet (422 and 603 eggs per female) in both the generations,
but the differences were not significant. Complete or partial replacement of agar-agar with tapioca
granules was not suitable for use in artificial diets. The results indicated that modified chickpea flour
based diet was quite appropriate for rearing H. armigera under laboratory condition
Physical Studies in III-Nitride Semiconductor Alloys
Many theoretical and experimental works are made on the wurtzite phase of indium nitride (InN), gallium nitride (GaN), aluminum nitride (AlN), and their Ternary alloys. On the other side, few experimental data exist for their cubic phases where as theoretical studies show they are performing more interesting. Inclusive depiction of III-Nitride Semiconductors is demonstrated and consequence of existent Research is emphasised. The Electrical and Optical properties of III-Nitrides from binary Semiconductors are appraised using the Principle of additivity comprising quadratic expressions. The Electrical and Optical properties learned in this group restrain Refractive index, Optical polarizability, Absorption coefficient and Energy gap. A similarity of these data is made with reported information facts wherever attainable. The worth of current displayed method build from refractive indices with out need for refined experimental methods is stressed. The beneficial of this Nitride Group Alloys is also summarized
Effect of magnesium chloride on growth, crystalline perfection, structural, optical, thermal and NLO behavior of gamma-glycine crystals
In the present study, single crystals of gamma-glycine possessing excellent non-linear optical properties were successfully grown at room temperature in the presence of magnesium chloride (MgCl2) for the first time by using the slow solvent evaporation method. The second harmonic conversion efficiency of gamma-glycine crystal was determined using Kurtz powder technique with Nd:YAG laser and was found to be 6 times greater than that of the standard inorganic sample potassium dihydrogen phosphate (KDP). The crystalline perfection of the grown crystal was analyzed using high-resolution X-ray diffraction (HRXRD) rocking curve measurements. The grown crystal was subjected to single crystal XRD and powder XRD, which confirmed that the crystal has hexagonal structure and belongs to space group P3(1). Inductively coupled plasma optical emission spectrometry (ICP-OES) was carried out to quantify the concentration of Mg element in the grown gamma-glycine single crystal. Fourier transform infrared (FUR) spectral studies were made to identify the functional groups. The optical band gap was likewise estimated for gamma-glycine crystal using UV-vis-NIR study. The optical measurements of gamma-glycine crystal helped to calculate the optical constants such as refractive index (n), the extinction coefficient (K), electric susceptibility (chi(c)) and both the real (epsilon(r)) and imaginary (epsilon(i)) components of the dielectric permittivity functions of photon energy, which is essentially required to develop optoelectronic devices. Thermogravimetric analysis (TGA) and differential thermal analysis (DTA) were used to study thermal stability and decomposition point of the grown crystal
Crystal growth and characterization of gamma-glycine grown from potassium fluoride for photonic applications
Single crystals of γ-glycine, an organic nonlinear optical material have been synthesized in the presence of potassium fluoride (KF) by slow evaporation technique at ambient temperature. The size of the grown crystal is up to the dimension of 12 mm × 10 mm × 8 mm. The γ-phase was confirmed by single crystal X-ray diffraction, powder XRD and the FTIR analysis. Optical absorption spectrum reveals that the grown crystal has good optical transparency in the entire visible region with an energy band gap of 5.09 eV, which is an essential requirement for a nonlinear optical crystal. Thermal stability of the grown γ-glycine crystal was determined using the thermo gravimetric and differential thermal analyses. The NLO activity of γ-glycine was confirmed by the Kurtz powder technique using Nd:YAG laser and the grown crystal exhibits high relative conversion efficiency when compared to potassium dihydrogen phosphate (KDP)