Development and validation of a simple analytical method for the determination of 2,4,6-trichloroanisole in wine by GC–MS

A novel method for the residue analysis of wine spoilage compound 2,4,6-trichloroanisole is reported. Wine (60 ml) was extracted with 2 ml toluene in presence of 24 g MgSO₄ and 6 g NaCl. Cleanup of the toluene phase by dispersive solid phase extraction with mixture of 100 mg CaCl₂, 25 mg primary secondary amine and 50 mg MgSO₄ was effective in minimising co-extractives and matrix effects. Time-of-flight and tandem mass spectrometric parameters were optimised to achieve linearity over 0.25–500 ng ml⁻¹ and method detection limit 0.0083 ng ml⁻¹ which is well below the odour threshold of 0.04 ng ml⁻¹. Recoveries at 0.04, 0.2 and 0.8 ng ml⁻¹ were within 80–110% (±8%). The method was reproducible when tested for Argentinean wines with intra-laboratory Horwitz ratios being <0.20 in white and red wines at both the laboratories of India and Argentina. The method could be successfully applied for incurred wine samples.     

Editorial

Pattern Analysis and Applications -     

Effectiveness of Annealing on the Structural,Electrical, and Optical Properties of Erbium(III)-tris(8-hydroxyquinolinato) Films for Possible Use in OLEDs

Journal of Inorganic and Organometallic Polymers and Materials - In this study, Erbium tris-8-hydroxyquinoline (Erq3) thin films were deposited on a cleaned glass substrate using the thermal...     

Sorptive storage of natural gas onto dry and wet phillipsite: Study of dynamics,storage and delivery

In this work, storage of methane on phillipsite, a naturally occurring zeolite, was studied on wet and dry basis. The temperature and pressure dynamics were investigated. The temperature gradient due to the adsorption of methane on phillipsite was less than 1 °C indicating higher thermal conductivity of this material. A decreased in temperature resulted in higher adsorption capacity. Storage of methane onto phillipsite can be enhanced by wetting the bed and thus hydrate formation. The time needed to reach equilibrium depends strongly on the water content of the adsorbent. The results revealed that the total delivery capacities for dry and wet phillipsite were 32.5 V/V and 74.13 V/V, respectively. A maximum delivery capacity of 138 V/V was reached using wet phillipsite with 350 g water content. The volumetric delivery capacity results indicated that the steady state delivery is more realistic for adsorptive natural gas (ANG) systems.     

Optimizing size and distribution of voids in phenolic resins through the choice of catalyst types

Phenolics are widely used for over a century in different industries due to their chemical resistance and thermomechanical properties. However, the presence of voids in phenolic resins has negative effects on the mechanical properties and a conventional approach is to avoid these by utilizing very long cure cycles. Our alternative approach investigates the tailoring of void size and distribution to achieve a better balance between processing time and mechanical properties. Therefore, we produced phenolic resin with a void-free microstructure by a long cure cycle as a reference. To alter the void size and distributions, we utilized different catalysts and a short cure cycle to obtain phenolic resins and test their flexural properties with respect to the reference. We investigated the fracture surfaces of all materials by SEM, FTIR and compared results to finite element modeling that confirmed the effects of different void size and distributions on the mechanical properties. © 2019 The Authors. Journal of Applied Polymer Science published by Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48249.     

Changes in adolescent online social networking behaviors from 2006 to 2009

As online social networking has become an immersive and pervasive phenomenon, traditional considerations and expectations of personal privacy have been drastically altered. This paradigmatic change has led to adolescents possibly making themselves vulnerable to embarrassment, censure, damage to one’s name or reputation, or even victimization by others because of unwise postings or revelations online. The current study sought to determine the extent to which adolescent information disclosure on MySpace.com has changed between 2006 and 2009. We found significant changes in the nature of personal content made publicly available across the two time points and a trend in which teens are being increasingly more selective and discrete when it comes to what they share and with whom they share it.     

Dehydration of potato slices following brief dipping in osmotic solutions: Effect of conditions and understanding the mechanism of water loss

A novel variant of osmotic dehydration, named here as postdipping dehydration—where a material is dipped in a salt or sugar solution for a very short time followed by simple exposure to ambient conditions was explored with the aim of lowering water content of potato slices but at the same time not gain a high level of sugar/salt. The rate of water loss, which was rapid initially, was found to approach equilibrium. This article also explored whether the water loss process could subsequently be kick started once again, by employing a multistage process, where each stage consisted of osmotic solution dipping followed by ambient holding of the potato slices that had reached equilibrium in the earlier stage. Water loss values comparable to conventional osmotic dehydration could be achieved thus, but with significantly lower overall solid gain (<50%)—which can potentially yield a significantly healthy product option.     

Inhibition of Golgi mannosidase II with mannostatin A analogues: synthesis, biological evaluation, and structure-activity relationship studies

Mannostatin and aminocyclopentitetrol analogues with various substitutions at the amino function were synthesized. These compounds were tested as inhibitors of human Golgi and lysosomal alpha-mannosidases. Modification of the amine of mannostatin had only marginal effects, whereas similar modifications of aminocyclopentitetrol led to significantly improved inhibitors. Ab initio calculations and molecular docking studies were employed to rationalize the results. It was found that mannostatin and aminocyclopentitretrol could bind to Golgi alpha-mannosidase II in a similar mode to that of the known inhibitor swainsonine. However, due to the flexibility of the five-membered rings of these compounds, additional low-energy binding modes could be adopted. These binding modes may be relevant for the improved activities of the benzyl-substituted compounds. The thiomethyl moiety of mannostatin was predicted to make favorable hydrophobic interactions with Arg228 and Tyr727 that would possibly account for its greater inhibitory activity.     

Reduction of Hamilton's variational principle

This paper builds on the initial work of Marsden and Scheurle on nonabelian Routh reduction. The main objective is to carry out the reduction of variational principles in further detail. In particular, we obtain reduced variational principles which are the symplectic analogue of the well-known reduced variational principles for the Euler-Poincare equations and the Lagrange-Poincare equations. On the Lagrangian side, the symplectic analogue is obtained by suitably imposing the constraints of preservation of the momentum map.