The synthesis and characterization of asymmetric ultrafiltration membranes from recycled polyethylene terephthalate (PET) and polyvinylpyrrolidone (PVP) is reported. PET is currently used in many applications, including the manufacture of bottles and tableware. Monomer extraction from waste PET is expensive, and this process has not yet been successfully demonstrated on a viable scale. Hence, any method to recycle or regenerate PET once it has been used is of significant importance from scientific and environmental research viewpoints. Such a process would be a green alternative due to reduced raw monomer consumption and the additional benefit of reduced manufacturing costs. The membranes described here were prepared by a phase-inversion process, which involved casting a solution containing PET, m-cresol as solvent, and polyethylene glycol (PEG) of different molecular weights as additives. The membranes were characterized in terms of pure water permeability (PWP), molecular weight cut-off (MWCO), and flux and membrane morphology. The results show that the addition of PEG with high molecular weights leads to membranes with higher PWP. The presence of additives affects surface roughness and membrane morphology.

In situ ethylene polymerizations with inorganic fillers were performed using catalyst based on titanium tetrachloride supported on polyethersulfone. The inorganic fillers used were MgO, TiO 2 , and CaCO 3 , which were pretreated with cocatalyst (methylaluminoxine) for better dispersion onto the polymer matrix. The formation of polyethylene (PE) within the whole matrix was confirmed by Fourier transform infrared studies. The wideangle X-ray diffraction profile of the synthesized PEs indicated the presence of crystalline region. It was found that the nature of inorganic filler did not have any remarkable effect on the melting characteristics of the polymer, but the degree of crystallinity of PE was found to be higher for TiO 2 -filled PE. The amount of filler incorporated into the matrix was also evaluated through thermogravimetric analysis, where TiO 2 -filled PE showed $ 49% of filler material, which was also reflected in the higher productivity obtained by this system. The morphology of the fillerfilled PEs was different, whereas the elemental dispersion was found to be uniform on the surface as elucidated through energy-dispersive X-ray spectroscopy.

:The vibrational spectra analysis of Sitagliptin was calculated using density functional theory method(B3LYP) by employing 6-31G (d, p) basis set, compared with experimental FT-IR and FT-Raman spectra in the region of 4000-400 cm -1 and 4000-100 cm -1 . The electronic properties like Homo-Lumo energies and molecular electrostatic potential (MEP) have been computed. The experimental FT-IR and FT-Raman spectra were compared with theoretical spectrograms. The Mullikan atomic charges were also calculated. The inter and intramolecular interactions of title molecule has been visualized using NBO analysis. Electronic stability of the title compound arising from hyper conjugative interactions and charge delocalization were also investigated based on NBO analysis.

The inhibition of mineralization of urinary stone forming minerals by medicinal plantsi.e. Achyranthes asperaLinn,Passiflora leschenaultiiDC,Solena amplexicaulis(Lam.) Gandhi,Scoparia dulcisLinn andAerva lanata(Linn.) been investigated. The inhibition efficiency was studied. Increased intake of fruits juice and seed extract of our plants would be helpful in urinary stone prophylaxis.

Synthesis and characterization of asymmetric ultrafiltration membrane made from polysulfone (PS), with an antioxidant 2,2 -methylenebis (6-tert-butyl-4-ethylphenol) (MBEP) as an additive, is reported in this work. The membrane was prepared by phase-inversion process from casting solution containing PS polymer, dichloromethane solvent, and antioxidant MBEP as an additive. Polyvinylpyrrolidone (2 wt% concentration) was added in the casting solution as pore former. The membrane was characterized in terms of thermogravimetric analysis (TGA), differential scanning calorimetry, oxidative-induction time test, mechanical measurements and cross-flow filtration for milk concentration, and scanning electron microscopy (SEM). From TGA, it is noted that volatilization of MBEP started before its boiling point (198 • C), indicating that the antioxidant has interacted with the PS, and the results indicate that highest residual weight percentage was obtained for higher weight percent antioxidant filled membrane substantiating its higher thermal stability. From SEM images, it is observed that as MBEP content gets higher dispersion of particles in the membrane, the matrix becomes more homogeneous. The other results revealed that the addition of antioxidant MBEP produced a membrane with higher thermal stability. The presence of additive also affects the surface roughness, membrane morphology, and mechanical strength. C

The Fourier transform-Raman (FT-Raman) and Fourier transform infrared (FT-IR) spectra of (RS)-5-(4-[2-(5-ethylpyridin-2-yl) ethoxy] benzyl) thiazolidine-2,4-dione (pioglitazone) were studied in the region of 4000-100 cm-1 and 4000-400 cm-1 respectively. The theoretical spectral investigation of pioglitazone are also carried out by using density functional theory (DFT) with 6-31G (d,p) basis set. Experimental and theoretical values are compared. The entire vibrational assignments were carried out on the basis of the potential energy distribution (PED) of the vibrational modes using VEDA 4 program. The optimized geometry of the compound was calculated from the DFT-B3LYP. HOMO-LUMO energy gap has been calculated. The molecular geometry parameters like bond angle and bond length have been computed. The molecular stability arising from hyper conjugative interaction, charge delocalization has been analyzed using natural bond orbital (NBO) analysis. The Mullikan atomic charges have been computed. The molecular electrostatic potential (MEP) are also carried out to study the molecular interactions in the title molecule.

Recebido em 30/8/10; aceito em 4/3/11; publicado na web em 12/5/11In situ ethylene polymerizations were performed using bis(cyclopentadiene)titanium dichloride supported on polyethersulfone as catalyst. The bis(cyclopentadiene)titanium dichloride supported on polyethersulfone catalyst activity estimated by ethylene polymerization was 360 kgPE/molTi/h. During polymerization the fillers used were montmorillionite nanoclays having surface modifications with 35-45 wt% dimethyl dialkyl(14-18)amine (FA) and 25-30 wt% trimethyl stearyl ammonium (FB). These fillers were pretreated with methylaluminoxine (MAO; cocatalyst) for better dispersion onto the polymer matrix. The formation of polyethylene within the whole matrix was confirmed by FTIR studies. It was found that the nature of nanofiller did not have any remarkable effect on the melting characteristics of the polymer. TGA study indicates that nanoclay FB filled polyethylene has higher thermal stability than nanoclay FA filled polyethylene. The melting temperature of the obtained polyethylenes was 142 °C, which corresponds to that synthesized by the polyether sulfone supported catalyst.

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