myo-Inositol, one of nine isomers of hexahydroxycyclohexane, comprises almost all of the naturally occurring inositol of mammalian tissues. However, a small amount of chiro-inositol, an optically active epimer of myo-inositol, is also present and may have physiological importance. D-chiro-Inositol was recently found unexpectedly in inositol phosphoglycans thought to be mediators of insulin signaling (1, 2) and in glycosylphosphatidylinositol protein anchors (3, 4). The related compound pinitol, 3-O-methyl-D-chiro-inositol, is a prominent component of dietary legumes such as soybeans (5). Clinical studies have demonstrated that diabetic patients excrete large amounts of D-chiro-inositol in urine related to the degree of diabetic glycemic control (6, 7), although the opposite result has also been reported (8). Treatment of diabetics with insulin resulted in decreased urinary excretion and transient elevation of plasma D-chiro-inositol (6). These experiments show that D-chiro-inositol and related substances are recognized by cell systems, but little is known about the biochemical pathways involved.To allow further study of this unusual cyclitol with high sensitivity we have prepared radiolabeled D-chiro-inositol by reduction of D-chiro-3-inosose using sodium borotritide. The reaction product, D-chiro-[3-3 H]inositol, is taken up avidly by cultured HepG2 liver cells in a pathway that is stereospecific and shared with myo-inositol. EXPERIMENTAL PROCEDURESMaterials-D-chiro-Inositol (lot 42136, no longer commercially available) and L-glucose were purchased from Calbiochem. Pinitol was donated by Dr. Andrew Falshaw of Industrial Research Ltd., Lower Hutt, New Zealand, and was also prepared from soybeans by ion exchange chromatography as described previously (5 Analytical Procedures-HPLC 1 was performed with an aminopropylsilica column (Supelcosil-LC-NH 2 , Supelco, Bellefonte, PA) using acetonitrile:water mixtures as mobile phase. Although good HPLC separation of most inositols has been reported with a calcium-form cation exchange resin designed for carbohydrates (9, 10), the separation between chiro-inositol and myo-inositol was incomplete. A previous HPLC separation of inositols reported by Ghias-Ud- Din et al. (11) showed excellent resolution of chiro-inositol and myo-inositol, but the column chemistry was proprietary and uncharacterized. At the suggestion of Dr. Daniel V. Phillips of the University of Georgia we tested the reported separations using an aminopropyl-silica column and have obtained very similar results, suggesting that the original column chemistry may have been aminopropyl-silica. chiro-Inositol and myo-inositol were separated at base line (retention volumes 10.8 and 12.8 ml, respectively), using a mobile phase of 76:24 acetonitrile:water with detection at OD 206. This HPLC system is very useful for the separation of inositols, inososes, and inositol methyl ethers.For GC/MS analysis inositol samples were derivatized by incubating with 10% pentafluoropropionic anhydride in acetonitrile at 65°C for ...

The surface of a polypropylene (PP) film was modified using acetone and acetone/oxygen. Significant improvement in surface energy was observed due to plasma treatment. The chemical nature and stability of the surface modification was studied by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The relative change in intensity was calculated for C-H stretch vibrations of a modified PP film to understand the reactive site for surface modification. Studies were carried out to mask the reactive site of PP by pretreatment in nitrogen plasma followed by treatment in acetone/oxygen. The peel strength and effect of aging were studied on acetone and acetone/oxygen plasma modified films.

Extrusion film casting (EFC) is an important melt processing operation which is extensively used to make polypropylene (PP) films. Linear PP shows significant amount of necking and draw resonance during EFC. One of the ways to reduce necking is to introduce long chain branches (LCB) on the polymer backbone. The long branches impart extensional strain hardening behavior thereby stabilizing the melt flow. In this work, we investigate the influence of long chain branching in polypropylene on the extent of necking in the EFC process. Laboratory scale EFC experiments were performed on homopolymer PP of linear and long chain branched architectures. Simulations of the EFC process were carried out using the one‐dimensional flow model of Silagy et al., Polym. Eng. Sci., 36, 2614 (1996) into which we incorporate two different multi‐mode molecular constitutive equations namely, the ‘eXtended Pom‐Pom’ equation (XPP, for long chain branched PP) and the ‘Rolie‐Poly’ equation (RP‐S, for linear PP). Our experimental data confirm that presence of long chain branching in PP reduces the extent of necking and our numerical predictions show qualitative agreement with experimental data, thereby elucidating the role of chain architecture on the extent of necking. POLYM. ENG. SCI., 55:1977–1987, 2015. © 2014 Society of Plastics Engineers

In this paper, a novel orthogonal slit cut stacked circular patch antenna (SC-SCPA) is proposed for multi band operations. The antenna structure is investigated by cutting two pair of orthogonal slits on the upper patch whose effects are studied in terms of the return loss, input impedance, gain, directivity, and radiation pattern. Multiple resonances are observed that too at lower frequency signifying the compactness and multiband nature of the proposed antenna. The antenna is resonating at four operating frequencies 7.4, 9.0, 9.4, and 10.8 GHz, and 27% reduction in size is achieved by slit cut stacked patch antenna. The proposed theory which is verified by simulation and theoretical results is in good agreement with the simulated results obtained by Ansoft's HFSS. The antenna is working in X-band from 7 to 12 GHz and applications pertaining to this regime are also discussed herein.

No abstract