Li<Subscript>1−<Emphasis Type="BoldItalic">x</Emphasis></Subscript>Sm<Subscript>1+<Emphasis Type="BoldItalic">x</Emphasis></Subscript>SiO<Subscript>4</Subscript> as solid electrolyte for high temperature solid-state lithium batteries

Lithium lanthanoid silicates are projected as promising solid electrolytes for solid-state high-temperature lithium batteries. Synthesis of Li_1−x Sm_1+x SiO₄ (x = 0.2 to 0.6) was carried using sol–gel method, and these compounds were characterized by thermogravimetry differential thermal analysis, X-ray diffraction, Fourier transform infrared, and SEM. Impedance measurements were carried out at different temperatures, and conductivity at different temperatures was calculated. The effect of an increase of samarium content on the conductivity of the solid electrolyte was studied in this paper. It was found that less samarium content exhibits good conductivity at higher temperatures.     

Electrochemical Sensing of Chemical Warfare Agent Based on Hybrid Material Silver‐aminosilane Graphene Oxide

The threat from chemical warfare agents (CWAs) imparts an alarming call for the global community not limited to human being but also extends as unprecedented environmental threat, hence, timely detection and degradation in the event of CWAs attack is very crucial. Herein, we describe a hybrid material of 3‐aminopropyltriethoxysilane (APTES) modified graphene oxide (GO) on glassy carbon (GC) electrode along with electrodeposited silver nanodendrimers (AgNDs) for the electrochemical detection and degradation of CWA sulphur mustard (HD). The AgNDs/APTES‐GO hybrid material was characterized by SEM, EDX, BET, TGA, Raman, UV‐Vis, XPS and XRD techniques. The AgNDs/APTES‐GO modified GC electrode was also characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Electrochemical studies indicated presence of electrocatalysis owing to the synergistic effect of AgNDs and GO for sensing CWA HD via reductive dehalogenation. The AgNDs/APTES‐GO modified GC electrode exhibited linearity for CWA HD from 5.3 μM to 42.4 μM. Constant potential electrolysis was performed with modified electrode and degradation products were analysed using GC‐MS, highlighting the great potential of graphene based hybrid material. This new strategy provides an opportunity for the development of “detect and destroy” system for the CWAs and other environmental toxic pollutant, which could help in mitigation of on‐ site events for first responders.     

How short-range attractions impact the structural order, self-diffusivity, and viscosity of a fluid

We present molecular simulation data for viscosity, self-diffusivity, and the local structural ordering of (i) a hard-sphere fluid and (ii) a square-well fluid with short-range attractions. The latter fluid exhibits a region of dynamic anomalies in its phase diagram, where its mobility increases upon isochoric cooling, which is found to be a subset of a larger region of structural anomalies, in which its pair correlations strengthen upon isochoric heating. This "cascade of anomalies" qualitatively resembles that found in recent simulations of liquid water. The results for the hard-sphere and square-well systems also show that the breakdown of the Stokes-Einstein relation upon supercooling occurs for conditions where viscosity and self-diffusivity develop different couplings to the degree of pairwise structural ordering of the liquid. We discuss how these couplings reflect dynamic heterogeneities. Finally, we note that the simulation data suggest how repulsive and attractive glasses may generally be characterized by two distinct levels of short-range structural order.     

Surface energies and self-assembly of block copolymers on grafted surfaces

We present a theoretical analysis of the self-assembly of diblock copolymers on surfaces grafted with random copolymers. Our results demonstrate that the surface energies of homopolymeric components on grafted surfaces differ from the corresponding values for self-assembled morphologies. Moreover, grafted random copolymers are shown to adapt their conformations in response to the morphology of the overlaying block copolymer film to create chemical inhomogeneities which modulate the interfacial interactions. Consequently, the surface energy differences between the different components on the grafted substrate do not serve as a useful measure to predict the stability of self-assembly of the diblock copolymer film.     

Synthetic studies on indolocarbazoles: total synthesis of staurosporine aglycon

A synthesis of staurosporine aglycon and its analogs was achieved in a 28-36% overall yield starting from 2-methylindole. The prominent key steps for the synthesis of the indolocarbazole alkaloids involved electrocyclization and nitrene insertion reactions.     

Transition Metal Chemistry of Diphosphazanes and Diphosphazane Monosulfides

Abstract

The reactions of chiral diphosphazanes. Ph₂PN((S)-*CHMePh)PPhY (Y =Ph, N₂C₃HMe₂-3,5) with [CpRu (PPh₃)₂Cl] and those of the monosulfides, Ph₂PN(R)P(S)Ph₂ (R = (S)-*CHMePh or CHMe₂) with Ru₃(CO)₁₂. [RhCl(cod)]₂ and [RhCI(CO)₂]₂ have been investigated. Molybdenum-palladium heterometallic complexes of the diphosphazanes, MeN(P(OR)₂)₂ (R = CH₂CF₃ or Ph) have been synthesised. Some unusual complexes have been obtained by the reductive carbonylation of cobalt and ruthenium halides in the presence of diphosphazanes, RN(PX₂)₂ (R = Me, X = OCH₂CS or OPh; R = CHMe₂, X = Ph). The structures of the products have been elucidated by NMR spectoscopy and in some cases confirmed by X-ray crystallography (e.g., 1–4).     

Optical and Radioiodinated Tethered Hsp90 Inhibitors Reveal Selective Internalization of Ectopic Hsp90 in Malignant Breast Tumor Cells

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Thermal decomposition of sodium propoxides

Sodium alkoxides, namely, sodium n-propoxide and sodium iso-propoxide were synthesized and characterized by various analytical techniques. Thermal decomposition of these compounds was studied under isothermal and non-isothermal conditions using a thermogravimetric analyzer coupled with mass spectrometer. The onset temperatures of decomposition of sodium n-propoxide and sodium iso-propoxide were found to be 590 and 545 K, respectively. These sodium alkoxides form gaseous products of saturated and unsaturated hydrocarbons and leave sodium carbonate, sodium hydroxide, and free carbon as the decomposition residue. Activation energy, E _a, and pre-exponential factor, A, for the decomposition reactions were deduced from the TG data by model-free (iso-conversion) method. The E _a for the decomposition of sodium n-propoxide and sodium iso-propoxide, derived from isothermal experiments are 162.2 ± 3.1 and 141.7 ± 5.3 kJ mol^?1, respectively. The values obtained from the non-isothermal experiments are 147.7 ± 6.8 and 133.6 ± 4.1 kJ mol^?1, respectively, for the decomposition of sodium n-propoxide and sodium iso-propoxide.     

InCl3-CH3CN-H2O: an efficient catalyst-solvent combination for the synthesis of Perlin aldehydes and related compounds. Application in the synthesis of unnatural l-azasugars

InCl₃-CH₃CN-H₂O has been found to be an efficient catalyst-solvent combination for the synthesis of Perlin aldehydes and related compounds. While acetylated glycals afforded the Perlin aldehydes directly with InCl₃ and water, benzylated glycals on the other hand provided the hemiacetals under identical condition. The methodology reports a non-mercurial approach to Perlin aldehydes. Noteworthy is that this reaction is more facile as well as highly selective with glycals possessing a hydroxyl as a leaving group than with a benzyloxy group. Extension of this reaction to 2-C-hydroxymethyl glycals resulted in the formation of the corresponding hemiacetals, which were further transformed in to unsaturated azasugars with an exo-methylene group at C-2 position. Glycosidase inhibition studies reveal that these compounds display selectivity in inhibiting glucosidases rather than galactosidases.