Deen Dayal Upadhyay Gorakhpur University

About: Deen Dayal Upadhyay Gorakhpur University is a education organization based out in Gorakhpur, Uttar Pradesh, India. It is known for research contribution in the topics: Thermal decomposition & Lymnaea acuminata. The organization has 1032 authors who have published 1591 publications receiving 21734 citations. The organization is also known as: Gorakhpur University.

Photometric and polarimetric studies of three W UMa-type binaries: FZ Ori, V407 Peg and LP UMa

Abstract: We present analyses of new optical photometric observations of three W UMa-type contact binaries FZ Ori, V407 Peg and LP UMa. Results from the first polarimetric observations of the FZ Ori and V407 Peg are also presented. The periods of FZ Ori, V407 Peg and LP UMa are derived to be 0.399986, 0.636884 and 0.309898 d, respectively. The O−C analyses indicate that the orbital periods of FZ Ori and LP UMa have increased with the rate of 2.28×10−8 and 1.25×10−6 d yr−1, respectively and which is explained by transfer of mass between the components. In addition to the secularly increasing rate of orbital period, it was found that the period of FZ Ori has varied in sinusoidal way with oscillation period of ∼30.1 yr. The period of oscillations are most likely to be explained by the light-time effect due to the presence of a tertiary companion. Small asymmetries have been seen around the primary and secondary maxima of light curves of all three systems, which is probably due to the presence of cool/hot spots on the components. The light curves of all three systems are analysed by using Wilson-Devinney code (WD) and the fundamental parameters of these systems have been derived. The present analyses show that FZ Ori is a W-subtype, and V407 Peg and LP UMa are A-subtype of the W UMa-type contact binary systems. The polarimetric observations in B, V, R and I bands, yield average values of polarization to be 0.26±0.03, 0.22±0.02, 0.22±0.03 and 0.22±0.05 per cent for FZ Ori and 0.21±0.02, 0.29±0.03, 0.31±0.01 and 0.31±0.04 per cent for V407 Peg, respectively.

Stepwise substitution of oxo-centered, trinuclear chromium(III) carboxylates with Schiff base

Abstract: Oxo-centered, trinuclear, mixed-ligand complexes of chromium(III) have been synthesized by stepwise substitutions of acetate ions of [Cr3O(OOCMe)4(OOCR)3] · 3MeOH (1) and the isolated products of the type [Cr3O(OOCMe)2 (SB)(OOCR)3]PF6 · 3MeOH (2), [Cr3O(OOCMe)(SB)2(OOCR)3]PF6 · 3MeOH (3) and [Cr3O(SB)3(OOCR)3]PF6 · 3MeOH (4) [where R = C13H27 and HSB = C6H4(OH)CHNC6H4Cl] have been characterized by a full battery of complementary physico–chemical methods including spectral (infrared, electronic, FAB mass and powder XRD) studies, elemental and thermogravimetric analyses, molar conductance and magnetic susceptibility measurements. The infrared spectra suggest the bridging nature of both carboxylate and Schiff base anions along with ν asym(Cr3O) vibrations in the complexes. The trinuclear nature of the complexes has been assessed from FAB mass data. Electronic spectra and magnetic moment values were consistent with chromium(III) ion present in an octahedral environment which was supported by their powder X-ray diffraction data. Cyclic voltammetric data of complex (4) indicate a reversible oxidation wave and an irreversible reduction wave in the range − 1.2–0.6 V. The decomposition pathway of all the complexes has been discussed on the basis of thermogravimetric analysis data. Conductance data indicate the monocationic nature of the complexes and their plausible structure has been established on the basis of above physico–chemical studies.

Alterations in blood electrolytes of a freshwater catfish Heteropneustes fossilis in response to treatment with a botanical pesticide, Nerium indicum leaf extract

Abstract: The present study aimed at investigating the effects of Nerium indicum leaf extract on the blood electrolytes of Heteropneustes fossilis for short- and long term. Fish were subjected to Nerium indicum leaf extract for short term (11.27 mg/L i.e. 0.8 of 96 h LC50) and long term (2.81 mg/L i.e. 0.2 of 96 h LC50). Fish were killed on each time intervals from control and experimental (Nerium indicum) groups after 24, 48, 72, and 96 h in short-term exposure and after 7, 14, 21, and 28 days in long-term experiment. Blood samples were analyzed for calcium and inorganic phosphate levels. Acute exposure of Nerium indicum leaf extract caused a progressive decrease in the serum calcium levels after 48 h in fish H. fossilis, which persists till the close of the experiment (96 h). The serum inorganic phosphate levels remain unaffected till 48 h in the Nerium indicum leaf extract–exposed fish. After 72 and 96 h, the levels exhibit a decrease. Chronic Nerium indicum leaf extract treatment provoked a decrease in serum calcium levels at day 14. This decrease continues till 28 days. The serum phosphate level of the Nerium indicum leaf extract–treated fish decreases on day 14 and 21. However, on day 28, the levels become close to the normal values. We conclude that Nerium indicum leaf extract exposure alters the blood electrolytes of the fish, thus causing physiological disturbances which might affect seriously the normal vital functions, growth rate, reproduction, and their survival in nature.