Showing papers by "Deen Dayal Upadhyay Gorakhpur University published in 2007"

Pollution tolerance and distribution pattern of plants in surrounding area of coal-fired industries.

Abstract: Higher concentration of SO2 and particulate matters was reported in surrounding areas of coal-fired industries which influences the distribution pattern of plants. Sensitive plant species are abolished from such areas, however, only pollution tolerant species survive under stress conditions. The present study was designed to investigate the vegetation composition around coal-fired industries i.e. brick industries. To categorise plants as sensitive or resistant air pollution tolerance index (APTI) value was calculated. Out of 99 plants studied, Ricinus communis with APTI 81.10 was found to be the most resistant wild plant showing uniform distribution at all the polluted sites. On the other hand, Lepidium sativum with APTI 5.27 was recorded as the most sensitive plant and found to be present only at the less polluted sites.

Similarity solutions for the flow behind an exponential shock in a non-ideal gas

Abstract: Similarity solutions for the flow of a non-ideal gas behind a strong exponential shock driven out by a piston (cylindrical or spherical) moving with time according to an exponential law are obtained. Similarity solutions exist only when the surrounding medium is of constant density. Solutions are obtained, in both the cases, when the flow between the shock and the piston is isothermal or adiabatic. It is found that the assumption of zero temperature gradient brings a profound change in the density distribution as compare to that of the adiabatic case. Effects of the non-idealness of the gas on the flow-field between the shock and the piston are investigated. The variations of density-ratio across the shock and the location of the piston with the parameter of non-idealness of the gas $${\overline{b}}$$ are also obtained.

Formation of CaO from thermal decomposition of calcium carbonate in the presence of carboxylic acids

Abstract: Effect of 5% tartaric, succinic and citric acids on the decomposition of CaCO3 have been studied by TG-DSC and X-ray diffraction techniques. The decomposition temperature of CaCO3 is not decreased and at the same time particle size distribution and morphology of CaO are changed as determined by laser granulometer and SEM studies.

Impedance spectroscopy study of an organic semiconductor: Alizarin

Abstract: The electrical properties of alizarin, a π-conjugated organic semiconductor, were investigated by the complex impedance spectroscopy technique. A transition from semiconducting to conducting state has been observed and the transition temperature shifts to higher side with the increment in frequency. The dielectric relaxation was found to be of non-Debye type (polydispersive). Evidences of temperature-dependent electrical relaxation phenomena as well as negative temperature coefficient of resistance (NTCR) character of the sample have also been observed. The AC conductivity obeys the power law and the dispersion in conductivity was observed in the lower frequency region. Also, the frequency-dependent AC conductivity at different temperatures indicated that the conduction process is thermally activated process. The activation energy, density of states at Fermi level and number of π-electrons per molecule has been estimated from AC conductivity–temperature data and was found, respectively, to be 0.78 eV, 1.2×1019 cm−3 eV−1 and 25. Modulus analysis has indicated the possibility of hopping mechanism for electrical transport processes in the system with non-exponential-type conductivity relaxation.

Self-similar adiabatic flow headed by a magnetogasdynamic cylindrical shock wave in a rotating non-ideal gas

Abstract: Similarity solutions are obtained for one-dimensional adiabatic flow behind a magnetogasdynamic cylindrical shock wave propagating in a rotating non-ideal gas in presence of an azimuthal magnetic field. The density of the medium ahead of the shock is assumed to be constant. In order to obtain the similarity solutions the angular velocity of the ambient medium is assumed to be obeying a power law and to be decreasing as the distance from the axis increases. It is found that the similarity solutions exist, in both the cases, when the initial magnetic field is constant or obeying a power law. The effects of an increase in the value of the index for variation of angular velocity of the ambient medium, in the value of the parameter of the non-idealness of the gas and in the strength of the initial magnetic field are obtained.

Preparation, X-ray crystallography, and thermal decomposition of some transition metal perchlorate complexes of hexamethylenetetramine.

Abstract: The perchlorate complexes of manganese, nickel, and zinc with hexamethylenetetramine (HMTA) of the general formula [M(H2O−HMTA−H2O)2(H2O−ClO4)2(H2O)2] (where M = Mn, Ni, and Zn) have been prepared and characterized by X-ray crystallography. Thermal studies were undertaken using thermogravimetry (TG), differential thermal analysis (DTA), and explosion delay (DE) measurements. The kinetics of thermal decomposition of these complexes was investigated using isothermal TG data by applying isoconversional method. The decomposition pathways of the complexes have also been proposed. These were found to explode when subjected to higher temperatures.

Characterization of ionically bound peroxidases from apple (Mallus pumilus) fruits.

Abstract: Ionically bound peroxidases (POD) were salt extracted from the pulp of four Indian apple varieties, i.e., Golden delicious HP, Golden delicious JK, Red delicious, and Royal delicious. They were precipitated with chilled ethanol. Thermal treatments of partially purified enzymes were given from 40-70 degrees C for 30 minutes. Golden delicious HP peroxidase showed thermostability at 60 degrees C, while three other peroxidases were observed at 50 degrees C. Phenolic compounds (i.e., caffeic acid, ferulic acids, p-coumaric acid, protocatechuic acid) and metal ions (i.e., Cu2+ and Fe2+) activated all apple peroxidases. However, Mn2+ inhibited the peroxidases from Golden delicious HP, Golden delicious JK, and Red delicious, and a substantial increase was observed in Royal delicious peroxidase. Mg2+ inhibited the peroxidases from Golden delicious HP and Red delicious, but marginal activation was reported in peroxidases from Golden delicious JK and Royal delicious. Zn2+ established stimulation in Golden delicious HP and Golden delicious JK peroxidases, but inhibition was observed in peroxidases in Red delicious and Royal delicious.. Methionine, proline, tryptophan, and valine stimulated all four apple peroxidases, but cysteine showed inhibition in Golden delicious JK.

Synthesis, spectral and antimicrobial studies of triorganotin(IV) 3(2′-hydroxyphenyl)-5-(4-substituted phenyl) pyrazolinates

Abstract: Triorganotin(IV) pyrazolinates of the type R3Sn(C15H12N2O · X) [where C15H12N2O · X = 3(2′-hydroxyphenyl)-5(4-X-phenyl)pyrazoline {where X = H (a); CH3 (b); OCH3 (c); Cl (d) and R = Me, Pr n and Ph}] have been synthesized by the reaction of R3SnCl with the sodium salt of pyrazolines in a 1 : 1 molar ratio, in anhydrous benzene. These newly synthesized derivatives have been characterized by elemental analysis (C, H, N, Cl and Sn), molecular weight measurement as well as spectral studies [IR and multinuclear NMR (1H, 13C and 119Sn)]. The bidentate behaviour of the ligands was confirmed by IR, 1H and 13C NMR spectral data. Trigonal bipyramidal structure around tin(IV) atom for R3Sn(C15H12N2O · X) has been suggested. The free pyrazoline and a few triorganotin(IV) pyrazolinates have also been screened for their antibacterial and antifungal activities. Some triorganotin(IV) pyrazolinates exhibit higher antibacterial and antifungal effects than free pyrazoline and some of the antibiotics.

Inhomogeneous perfect fluid universe with electromagnetic field

Abstract: Cylindrically symmetric inhomogeneous cosmological model for perfect fluid distribution with electromagnetic field is obtained. The source of the magnetic field is due to an electric current produced along the z-axis. F12 is the non-vanishing component of electromagnetic field tensor. To get the deterministic solution, it has been assumed that the expansion θ in the model is proportional to the shear σ. Physical and geometric aspects of the models are also discussed in presence and absence of magnetic field.

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.

Synthesis, Spectroscopic, and Antimicrobial Studies of Binuclear Metallocene (M = Ti, Zr, or Hf) Derivatives of Bis(mercaptoazoles)

Abstract: The reactions of (η5 − C5H5)2MCl2 (M = Ti, Zr, or Hf) with mercaptoazoles (LH2), namely, bis(mercaptotriazoles), bis(mercap- tooxadiazoles), and bis(mercaptothiadiazoles) in 2 : 1 molar ratio, respectively, have been studied in dry tetrahydrofuran in the presence of n-butylamine and the binuclear complexes of the type [{(η − C5H5)2 M}2(L)] (M = Ti/Zr/Hf) are obtained. Tentative structural conclusions are drawn for the reaction products based upon elemental analysis, electrical conductance, magnetic moment, and spectral data (UV-Vis, IR, 1H NMR, and 13C NMR). FAB-mass spectra of few complexes of each series were also carried out to confirm the binuclear structures. Studies were conducted to assess the growth-inhibiting potential of the complexes synthesized, and the ligands against various fungal and bacterial strains.

Synthesis and Characterization of Samarium (III) Tris(O,O′ -Dialkyl and Alkylene Dithiophosphates) and Their Adducts with Nitrogen and Phosphorus Donor Bases

Abstract: Samarium (III) tris(dithiophosphates, [SmS2P(OR)2 3.3H2O] (where R = ─CH2CH2CH3 or ─C6H5) and [SmS2PO2G3.3H2O] [where G = ─C(CH3)2CH2CH(CH3)─, ─CH2C(CH3)2CH2-, ─C(CH3)2C(CH3)2-, ─CH2CH2CH(CH3), ─CH2C(C2H5)2CH2-, and ─CH(CH3)CH(CH3)-], were prepared by a reaction of SmCl3.6H2O and ammonium dithiophosphates in distilled water. Adducts of the type [SmS2P(OR)2 3.nL] and [SmS2PO2G3.nL] [where n = 1, L = N2C10H8 and n = 2, L = P(C6H5)3] were prepared by a reaction of samarium (III) tris(dithiophosphates) and nitrogen or phosphorus donor bases in benzene. These newly synthesized compounds have been characterized by elemental analysis, molecular weights measurement, thermogravimetric analysis, UV-visible, IR, and 1H and 31P NMR spectral studies. Coordination numbers of eight and nine are suggested for samarium (III) in these derivatives.

Sodium and silver phosphate glasses doped with chlorides of Fe, Mn and Zn

Abstract: A number of samples of sodium and silver phosphate glasses doped with various compositions of some transition metals viz. iron, manganese and zinc chlorides alongwith undoped samples of sodium and silver phosphate glasses were synthesized and characterized by X-ray diffraction, IR spectral, electrical conductivity and differential scanning calorimetry (DSC). The glass transition temperature (Tg) and crystallization temperature (Tc) values obtained from DSC curves were found to increase with increasing concentration of the dopant Fe/Mn/Zn chlorides in both sodium and silver phosphate glasses and the following sequence is observed:

Synthesis and Spectral Characterization of O,O′- Dialkyl and Alkylene Dithiophosphates of Neodymium (III)

Abstract: Neodymium (III) dithiophosphates of the type; [Nd{S2P(OR)2}Cl2.4H2O], [Nd{S2PO2G}Cl2.4H2O], [Nd{S2P(OR)2}2Cl.3H2O], [Nd{S2PO2 G}2Cl.3H2O], [Nd{S2P(OR)2}3.3H2O] and [Nd{S2PO2G}3.3H2O] [where R = ─CH2CH2 CH3or ──C6H5; G = ─C(CH3)2CH2CH(CH3)─, ─CH2C(CH 3 )2CH2─, ─C(CH3)2C(CH3)2─, ─CH2CH2CH(CH 3 ), ─CH2C(C2H5)2CH2─ and ─CH(CH 3 )CH(CH 3 )-] were prepared by the reaction of NdCl3.6H2O and ammonium dithiophosphates in distilled water. These newly synthesized compounds have been characterized by elemental analysis, TGA, UV-visible, IR, 1 H and 31 P NMR spectral studies. Coordination numbers of eight and nine are suggested for neodymium (III) in these compounds.

Pectin lyases of a few indigenous fungal strains

Abstract: Four pectin lyases (PNLs), producing indigenous fungal strains (Aspergillus flavus, A. niger, A. phoenicis and A. wentii), have been isolated from local samples. Enzymatic characteristics of PNLs produced by above fungal strains using citrus pectin have been found to be (respectively): Km, 0.38, 0.67, 0.55 and 0.32 mg/ml; pH, 8.0, 7.0, 5.0 and 7.0; and temperature, 50 °C for all PNLs. Effect of metal ions (Ag + , Ca ++ , Co ++ , Cu ++ , Hg ++ , K + , Mg ++ , Zn ++ , Na + ) and protein inhibitors (EDTA, sodium arsenate, sodium azide, potassium permanganate and potassium ferrocyanide) on the activities of PNLs has been determined.

Molecular Interaction between Naphthalene and 2,4-Dinitrophenol in Solid State

Abstract: Kinetics of the solid-state reaction between naphthalene and 2,4-dinitrophenol have been studied at different temperatures (30–50°C), and it was found that naphthalene diffuses toward 2,4-dinitrophenol. When naphthalene enters into the crystal lattice of 2,4-dinitrophenol, a 1:1 addition compound is formed with an orthorhombic crystal lattice, and the unit cell volume is much higher than the sum of the unit cell volumes of the components. As a result of this, cracks are formed and the reaction goes to completion. Computer calculations have shown that charge-transfer interaction occurs between the two components during the reaction.

Lanthanum(III) and prasedymium(III) complexes with piperazine dithiosemicarbazones

Abstract: Lanthanum(III) and praseodymium(III) complexes of the type [Ln(L)Cl(H2O)]2 (Ln = La(III) or Pr(III); LH2 = dithiosemicarbazone ligands derived from piperazine dithiosemicarbazide and benzaldehyde, 4-nitrobenzaldehyde, and 2-methoxybenzaldehyde) have been synthesized in methanol in the presence of sodium hydroxide. The complexes have been characterized by elemental analyses, molecular weight, molar conductance, electronic absorption, IR, and 1H and 13C NMR spectral studies. Nephelauxetic ratio, covalency parameter, and bonding parameter for these complexes have also been calculated. Thermal studies of the complexes have been carried out using TG, DTG, and DSC techniques. Kinetic parameters, such as apparent activation energy and order of reaction, were determined by the Coats-Redfern graphical method. The heats of reaction for different reaction steps were calculated from DSC curves.

Synthesis and Characterizations of Tin(IV)trithiophosphates and Their Adducts With Nitrogen Donor Bases

Abstract: Bis-(trithiophosphato)tin(IV) [(RO)P(S)S2]2Sn (where R = n-C3H7,i-C3H7,i-C5H11,-C6H11,-C6H5) were prepared by a reaction of methanolic solution of SnCl4 and dipotassium salt of trithiophosphates in a 1:2 molar ratio, and their adducts [(RO)P(S)S2]2Sn.N2C12H8 and [(RO)P(S)S2]2Sn.N2C10H8 were prepared by a reaction of methanolic solution of [(RO)P(S)S2]2Sn and N-donor bases in a 1:1 molar ratio. These newly synthesized derivatives have been characterized by elemental analysis; molecular weight measurement; and IR, 13C, 31P, and 119Sn NMR spectral studies. A coordination number of four and six is suggested for trithiophosphates of tin(IV) and their adducts with N-donor bases, respectively.

Studies on (non) energetic compounds

Abstract: Five salts of dichloroanilinium bromide (DCABr) were prepared and characterized by elemental and spectral studies. The thermal decomposition of DCABr was studied by using TG-DTG-DTA techniques and the results are discussed here. Kinetic parameters with the help of model fitting and isoconversional methods have been evaluated critically. A mechanism of decomposition has also been suggested.

Alginates as binding matrix for bio-molluscicides against harmful snails Lymnaea acuminata

Abstract: Various properties of alginates, such as its biodegradability, nontoxicity, biocompatibility, and ability to form gel with a variety of crosslinking agents in mild and aqueous conditions, make it a very useful binding matrix. Use of alginates as binding matrix for bio-molluscicides (crude Annona squamosa powder and acetogenin extracted from the seed powder of A. squamosa) is explored in this article. Effect of different crosslinkers as well as different loaded concentrations of biomolluscicides on the release were studied The release of the biomolluscicides extended over 25 and 20 days, respectively. The release was affected by the type of crosslinker and the amount of loaded concentration of the molluscicides. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007

Propagation of spherical shock waves in a dusty gas with radiation heat-flux

Abstract: The propagation of spherical shock waves in a dusty gas with radiation heat-flux and exponentially varying density is investigated in the paper. The equilibrium flow conditions are assumed to be maintained, and the radiation is considered to be of a diffusion type for an optically thick grey gas model. The shock wave moves with variable velocity and the total energy of the wave is non-constant. Non-similar solutions are obtained, and the effects of variation of the radiation parameter and time are investigated. The effects of an increase in (i) the mass concentration of solid particles in the mixture and (ii) of the ratio of the density of solid particles to the initial density of gas on the flow variables in the region behind the shock are also investigated.