Photopolymers: Synthesis and Characterization of Poly(3‐methacryloyloxystyryl‐2‐naphthyl ketone)

3‐Methacryloyloxystyryl‐2‐naphthyl ketone containing a photosensitive α,β‐unsaturated ketone moiety was synthesized and polymerized in methyl ethyl ketone using benzoyl peroxide as the initiator. The thermally stable polymer was characterized by means of UV, IR and NMR spectroscopy. The molecular weight data as obtained from gel permeation chromatography suggests a high tendency for chain termination by disproportionation. The photosensitivity of the polymer in the presence and absence of photosensitizers and the effect of solvent on the rate of photocrosslinking (see Figure) was also investigated.     

Inequivalent quantizations for non-linear σ model

We compute the homotopy groups ₀ and ₁ of the classical configuration space of anO(3) invariant field theory on ×, where is a compact two dimensional manifold for arbitrary genusg and- denotes the time coordinate. We also present the finite dimensional, unitary, irreducible, inequivalent representations of the appropriate fundamental groups and comment on some of their implications.     

Wahl’s conjecture holds in odd characteristics for symplectic and orthogonal Grassmannians

It is shown that the proof by Mehta and Parameswaran of Wahl’s conjecture for Grassmannians in positive odd characteristics also works for symplectic and orthogonal Grassmannians.      

A regioselective multicomponent protocol for the synthesis of novel bioactive 4-hydroxyquinolin-2(1H)-one grafted monospiropyrrolidine and thiapyrrolizidine hybrids

An expedient route toward the synthesis of 4-hydroxyquinolone grafted spiropyrrolidines or pyrrolizidines has been accomplished through 1,3-dipolar cycloaddition reaction of various azomethine ylides derived from isatin or acenaphthalene and sarcosine with 4-hydroxyquinolone derivatives as dipolarophile. The regio and stereo chemical outcome of the cycloaddition reaction is ascertained by X-ray crystallographic studies and spectroscopic techniques of the cycloadducts. Furthermore, cytotoxicity evaluation of selected compounds showed significant inhibition of cell proliferation against cervical as well as colon cancer cell lines.     

The t-analog of the level one string function for twisted affine Kac–Moody algebras

We study Lusztig?s t-analog of weight multiplicities, or affine Kostka–Foulkes polynomials, associated to level one representations of twisted affine Kac–Moody algebras. We obtain an explicit closed form expression for the unique t-string function, using constant term identities of Macdonald and Cherednik. This extends previous work on t-string functions for the untwisted simply-laced affine Kac–Moody algebras.     

Green Synthesized Silver Nanoparticles and Their Impact on the Antioxidant Response and Histology of Indian Major Carp <Emphasis Type="Italic">Labeo rohita</Emphasis>, with Combined Response Surface Methodology Analysis

Biosynthesis of silver nanoparticles has received considerable attention due to their cost-effective, eco-friendly and medicinal values. In this study, silver nanoparticles (Ag NPs) were synthesised using the aqueous leaf extracts of Piper nigrum. TEM images revealed that the particle is spherical with 20–50 nm in size. Furthermore, to evaluate the toxicity of synthesized Ag NPs, fish Labeo rohita were exposed to two different concentrations (2.5 µg/L as the treatment I and 5 µg/L as treatment II) for 35 days, and antioxidant parameters and histology of gill, liver and kidney were examined. A biphasic response in the activity of glutathione S-transferases (GST) was observed in gill and liver of fish. GST activity in the kidney of fish was significantly increased when compared to control group. Glutathione reductase (GR) activity in organs/tissue of fish were found to be increased while peroxidase (POD) activity was significantly decreased. Histopathological changes such as hyperplasia, proliferation of epithelial cells and fusion of lamellae were observed in both the concentrations. In liver, necrosis, nuclear degeneration and dilation of sinusoids were observed. Subsequently, the representative effects of POD activity were assessed based on the Box–Behnken Equation, 3-D contour plot and ANOVA analysis through response surface methodology analysis.     

Effect of the physico-chemical properties of vanadia/praseodymia on cyclohexanol decomposition

Vanadia supported on praseodymia (2, 6 and 10 wt.% V₂O₅) were prepared by wet impregnation and characterized by energy dispersive X-ray analysis (EDAX), X-ray diffraction (XRD), TGA/DTA and BET surface area measurements. Decomposition of cyclohexanol was conducted over these catalysts in the vapor phase. Acidity of the catalysts was measured by temperature programmed desorption using ammonia as a probe molecule. The structural and acidic properties were correlated to the total conversion and cyclohexene selectivity.     

Synthesis,spectra and redox behavior of copper(II) complexes of curcumin diketimines as models for blue copper proteins

Several new Cu^II complexes, having positive reduction potentials in an in situmanner, were synthesized by reaction of the Knoevenagel condensate, 4-salicylidene-1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione (from curcumin) with 4-X-anilines and CuCl₂. The solution electronic spectra of these complexes show intense absorption around 530 nm with unusual high extinction values (, 1600--3600 m^-1 cm^-1) due to the low symmetry L--d (Cu) LMCT transition. The e.s.r. spectral features with g _|| > g _|| > 2.0 having four g _|| values and a broadening of the g _||component with moderately low A _|| (110 × 10^-4 cm^-1) also suggest a lower symmetry around Cu^II. The cyclic voltammetric studies of the Cu^II complexes in MeCN show a positive reduction potential (E _pc=502--138 mV) with high peak-to-peak separation (E _p=87--335 mV). The higher and low A _||values together with positive reduction potentials for these Cu^II complexes suggest that they can mimic the functional properties of blue copper proteins, but have poor redox stability.