Biamperometric Determination of Au(III) & of Au(III) & U(VI) in Their Binary Mixtures.

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Bronchoalveolar lavage study in victims of toxic gas leak at Bhopal

Bronchoalveolar lavage using flexible fibreoptic bronchoscope was carried out in 50 patients 1-2½ yr after exposure to the ‘toxic gas’ at Bhopal. Thirty six patients in the analysis were categorised into 3 groups (viz., mild, moderate and severe), depending upon the severity of exposure. There was an increase in cellularity in the lower respiratory tract (alveolitis) of the severely exposed patients (in both smokers and non-smokers), compared to normals (P< 0.05). The increase in cellularity in severely exposed non-smokers was due to abnormal accumulation of macrophages (P<0.01), and in severely exposed smokers, to macrophages (P<0.01) and neutrophils (P<0.05). Mild and moderately exposed patients did not show significant change in cellularity in lower respiratory tract, compared to normal individuals (P>0.2). There was a trend towards increasing cellularity, as the severity increased (P < 0.0001) and higher numbers of total cells were seen in severely exposed smokers, suggesting that smoking is a risk factor. It appears, therefore, that subjects severely exposed to the toxic gas at Bhopal may have a subclinical alveolitis characterised by accumulation and possibly activation of macrophages in the lower respiratory tract. Smokers, who were exposed to the gas had in addition, accumulation of neutrophils

Discovering Crystal Forms of the Novel Molecular Semiconductor OEG-BTBT

This work is focused on a polymorphic and crystallographic study of a novel p-type organic semiconductor 2,7-bis(2-(2-methoxyethoxy)ethoxy)benzo[b]benzo[4,5]thieno[2,3-d]thiophene (OEG-BTBT). The well-known BTBT core is functionalized by eight-atom-long oligoethylene glycol side chains. Our results demonstrate the discovery of three crystal forms of the OEG-BTBT molecule, namely, Form I, Form II, and Form III, in different experimental conditions. Crystal structures of Form I and Form III are reported, while only unit cell indexing of Form II could be determined. Form I and Form II are enantiotropically related, and Form II is stable at temperatures higher than 127 °C. The kinetics of transformation to Form II was studied by the Avrami equation. Form III is a solvate crystal form which is rarely observed in the field of organic electronics, and upon release of dichloromethane, it converts to Form I. Furthermore, we studied the mechanical properties of the Form I crystals, which exhibit plastic bending upon applying mechanical stress in the [100] direction. This distinct mechanical behavior is rationalized by the slip layer topology, the intermolecular interactions energies from energy frameworks, and the Hirshfeld surface analysis

Ba{1-x}KxMn2As2: An Antiferromagnetic Local-Moment Metal

The compound BaMn2As2 with the tetragonal ThCr2Si2 structure is a local-moment antiferromagnetic insulator with a Neel temperature TN = 625 K and a large ordered moment mu = 3.9 mu_B/Mn. We demonstrate that this compound can be driven metallic by partial substitution of Ba by K, while retaining the same crystal and antiferromagnetic structures together with nearly the same high TN and large mu. Ba_{1-x}K_xMn2As2 is thus the first metallic ThCr2Si2-type MAs-based system containing local 3d transition metal M magnetic moments, with consequences for the ongoing debate about the local moment versus itinerant pictures of the FeAs-based superconductors and parent compounds. The Ba_{1-x}K_xMn2As2 class of compounds also forms a bridge between the layered iron pnictides and cuprates and may be useful to test theories of high Tc superconductivity.Comment: 5 two-column typeset pages, 5 figures, 20 references; v2: minor revisions, 4 new references, published versio