On certain generalized families of unified elliptic-type integrals pertaining to Euler integrals and generating functions

Elliptic-type integrals have their importance and potential in certain problems in radiation physics and nuclear technology. A number of earlier works on the subject contains several interesting unifications and generalizations of some significant families of elliptic-type integrals. The present paper is intended to obtain certain new theorems on generating functions. The results obtained in this paper are of manifold generality and basic in nature. Beside deriving various known and new elliptic-type integrals and their generalizations these theorems can be used to evaluate various Euler-type integrals involving a number of generating functions.      

Enhanced Production of Phenolic Compounds in Compact Callus Aggregate Suspension Cultures of Rhodiola imbricata Edgew.

Applied Biochemistry and Biotechnology - Rhodiola imbricata is a rare medicinal plant of the trans-Himalayan region of Ladakh. It is used for the treatment of numerous health ailments. Compact...     

Dielectric relaxation and conductivity studies on (PEO:LiClO4) polymer electrolyte with added ionic liquid [BMIM][PF6]: Evidence of ion–ion interaction

Polymer electrolytes, (PEO:LiClO₄)+x IL (1‐Buty‐3‐methylimidazolium hexafluorophosphate) with varying concentration of IL; x = 0,5,10,15,20 wt % have been prepared by solution cast technique and characterized by X‐Ray diffraction, differential scanning calorimetery, FTIR, conductivity and dielectric relaxation measurements in the frequency range of 100 Hz–5 MHz. Temperature dependence of relaxation frequency and conductivity were found to be typical of thermally activated process both at T > T_m and T < T_m. Composition dependence of conductivity, dielectric relaxation, and degree of crystallinity has also been studied. On addition of IL, the degree of crystallinity after a decrease at 5 wt % IL increases slightly at 10 wt % and then finally decreasing. Variation of conductivity and relaxation frequency with composition could only be partly explained on the basis of variation of degree of crystallinity. An additional feature of ion–ion interaction (contact ion pair formation between IL or salt cations and their associated anions) has been invoked which was supported by FTIR studies. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011     

Optical properties of Yb3+ ions in fluorophosphate glasses for 1.0 μm solid-state infrared lasers

Yb³⁺-doped fluorophosphate glasses were prepared by melt-quenching technique and characterized their spectroscopic properties to assess the laser performance parameters. The magnitude of absorption (emission) cross-sections at 975 nm for all the studied Yb³⁺-doped glasses is found to be in the range of 0.29–1.50 × 10^?20 (0.59–1.99 × 10^?20 cm²) which is much higher than those of commercial Kigre QX/Yb: 1.06 × 10^?20 (0.5 × 10^?20 cm²) laser glass. The luminescence lifetimes of ²F_5/2 level decrease (1.15–0.45 ms) with increase in Yb₂O₃ concentration (0.1–4.0 mol%). Effect of OH^? content on luminescence properties of Yb³⁺ ions has also been investigated. The effect of radiative trapping has been discussed by using McCumber (McC) and Fuchtbauer–Ladenburge (F–L) methods. The product of experimental lifetimes and emission cross-sections for 0.1 mol% Yb₂O₃-doped glass is found to be 2.28 × 10^?20 cm² ms which indicates that the higher energy storage and extraction capability could be possible. The detailed spectroscopic results suggest that the studied glasses can be considered for high-power and ultrashort pulse laser applications.     

A simple vapour phase decomposition (VPD) of quartz powder in a polypropylene vessel and determination of phosphorus by spectrophotometry

A simple, low pressure, low temperature vapour phase decomposition (VPD) of quartz powder has been developed for the determination of phosphorus. A platinum dish containing the quartz or silicon powder was placed inside a polypropylene vessel containing 40 ml of 1:1 mixture of HF and HNO(3). After capping the vessel, the entire assembly was heated on a water bath at approximately 90 degrees C for 8 h. The platinum dish was removed from the vessel, the sample solution was treated with 0.5 ml of H(2)SO(4) and 0.5 ml of HClO(4) and was heated on a hot plate till HClO(4) fumed out. The resultant solution was diluted to 40 ml ( approximately 0.4N), analysed for phosphorus by spectrophotometry as an ion-pair of molybdophosphate with crystal violet. Phosphorus contamination by reagents has been drastically reduced (around 250 times) compared to the conventional dissolution procedure. The optimum reaction conditions were [H(+)]=0.42N, [H(+)]/Mo=62 for the formation of molybdophosphate and its extraction into n-butyl acetate. No interferences due to fluoride, silicate (active silica) and arsenic (V) upto 6.7x10(3),2.7x10(3) and 2.0x10(3) times the content of phosphorus, respectively were observed. The LOD was found to be 0.066 mug g(-1) (+/-3 s). RSD is 0.4-2.3% and the molar absorptivity is 2.7x10(5) l mole(-1) cm(-1).     

Determination of traces of rubidium in high purity cesium chloride by electrothermal atomic absorption spectrometry (ETAAS) using boric acid as a modifier

The use of boric acid as a modifier for the determination of trace amount of rubidium in high purity cesium chloride matrix by electrothermal atomic absorption is described. It was found that the negative influence of the chloride matrix could not be eliminated using stabilized temperature platform (STPF) alone. Due to the high dissociation energy (D₀ = 427 kJ mol⁻¹) of rubidium chloride, it was difficult to dissociate in the gas phase and hence is lost. Elimination of interferences was achieved by the addition of boric acid as a chemical modifier. Diluted cesium chloride samples (5%, m/v) were analyzed applying the standard addition method. The characteristic mass of 24 pg was obtained. The detection limit of the proposed method is around 26 ng g⁻¹. The developed method was applied to the determination of traces of rubidium in high purity cesium chloride samples. The data obtained by this method were in good agreement with those obtained by other independent method like FAAS.     

Biocomputational Assessment of Natural Compounds as a Potent Inhibitor to Quorum Sensors in Ralstonia solanacearum

Ralstonia solanacearum is among the most damaging bacterial phytopathogens with a wide number of hosts and a broad geographic distribution worldwide. The pathway of phenotype conversion (Phc) is operated by quorum-sensing signals and modulated through the (R)-methyl 3-hydroxypalmitate (3-OH PAME) in R. solanacearum. However, the molecular structures of the Phc pathway components are not yet established, and the structural consequences of 3-OH PAME on quorum sensing are not well studied. In this study, 3D structures of quorum-sensing proteins of the Phc pathway (PhcA and PhcR) were computationally modeled, followed by the virtual screening of the natural compounds library against the predicted active site residues of PhcA and PhcR proteins that could be employed in limiting signaling through 3-OH PAME. Two of the best scoring common ligands ZINC000014762512 and ZINC000011865192 for PhcA and PhcR were further analyzed utilizing orbital energies such as HOMO and LUMO, followed by molecular dynamics simulations of the complexes for 100 ns to determine the ligands binding stability. The findings indicate that ZINC000014762512 and ZINC000011865192 may be capable of inhibiting both PhcA and PhcR. We believe that, after further validation, these compounds may have the potential to disrupt bacterial quorum sensing and thus control this devastating phytopathogenic bacterial pathogen.     

Ion–polymer and ion–ion interaction in PEO‐based polymer electrolytes having complexing salt LiClO4 and/or ionic liquid, [BMIM][PF6]

Ion–polymer and ion–ion association in polymer electrolyte films of PEO complexed with salt LiClO₄, ionic liquid (1‐butyl‐3‐methylimidazolium hexafluorophosphate, BMIMPF₆) and (LiClO₄ + BMIMPF₆) have been studied by laser Raman spectroscopy. The cations (Li⁺ and/or BMIM⁺) of the dopant salt/IL are shown to complex with the ether oxygen of the polymer backbone (i.e. C O C bond of PEO). The polymer–cation complexation results in the appearance of an additional peak at ∼1131 cm⁻¹ apart from the C O C stretching vibrations of PEO at ∼1062 and 1141 cm⁻¹. This peak due to polymer–cation complexation is relatively strong for LiClO₄ than BMIMPF₆, indicating stronger interaction for the former. In the PEO:LiClO₄ and PEO:BMIMPF₆ spectra, Raman peaks at 937 and 747 cm⁻¹, respectively related to Li⁺· ClO and BMIM⁺· PF ‘contact ion pairs’, have also been observed as a result of ion–ion association. In the polymer electrolyte PEO:LiClO₄ + BMIMPF₆ which contained two different anions, viz. ClO and PF, an interesting observation of the formation of ‘cross contact ion pairs’ viz. Li⁺· PF and BMIM⁺· ClO is also reported. Copyright © 2011 John Wiley & Sons, Ltd.