Reaction of cis-Ru(bpy)2Cl2 with 1-phenyl 5-(aminophenyl) 9-(2-pyridyl) benzimidazole derivatives: crystal structures of N-(4-chlorophenyl) imidazo[1,5a] pyridine and cis-[Ru(bpy)2(MeCN)2](ClO4)2

Reaction of 1-phenyl 5-(aminophenyl) 9-(2-pyridyl) benzimidazole derivatives (2) with cis-Ru(bpy)₂Cl₂ in MeCN results in the formation of N-(aryl) imidazo[1,5a] pyridine derivatives (4) and cis-[Ru(bpy)₂(MeCN)₂]²⁺ (5). Crystal structures of N-(4-chlorophenyl) imidazo[1,5a] pyridine (4b) and cis-[Ru(bpy)₂(MeCN)₂](ClO₄)₂ (5) are also reported.     

Mullite Fibre Mats by a Sol-Gel Spinning Technique

Fine grained, microcrystalline mullite (Al_4+2x Si_2–2x O_10–x) fibre mats with a web-like structure were fabricated by a sol-gel spinning technique using a multi-orifice spinneret. Points of contact in gel fibre mats helped in the formation of a web-like fibrous body having reasonable strength and very little dust formation after calcination. Strong and resilient fibres with diameters in the range 3–12 m were obtained by a single-step sol-gel method from spinnable sols devoid of organics as the binder aid. Crystallization of -alumina and mullite at about 900°C and 1250°C, respectively was confirmed by differential thermal analysis (DTA) and X-ray diffraction (XRD). Thermogravimetry (TG) indicated the removal of most of the volatiles at about 500°C accompanied by a weight loss of about 48%. Scanning electron microscopy (SEM) shows the presence of small grains (80–150 nm in size) in the fibres calcined at 1250°C. Fourier transformed infrared spectroscopy (FTIR) indicated the sequence of transformations taking place during heat-treatment of gel fibres at different temperatures. The individual fibres in the mats calcined at 1250°C exhibited a tensile strength of 1300–1600 MPa.     

Anomalies in quantitative measurement of 40K in natural samples

Journal of Radioanalytical and Nuclear Chemistry - Efficiency calibration by standard materials of known activity is usual protocol for γ-ray spectrometry. In general, 40K activity is measured...     

Selective N-monoalkylation of anilines catalyzed by a cationic ruthenium(II) compound

[(PPh₃)₂Ru(CH₃CN)₃Cl][BPh₄] has been found to catalyze the selective monoalkylation of anilines by alcohols.     

Concentration Dependent Transformation of Oligopeptide based Nanovesicles to Nanotubes and an Application of Nanovesicles

The concentration dependent transformation of an oligopeptide nanostructure from nanovesicles to nanotubes at neutral pH is presented. The oligopeptide Acp‐Tyr‐Glu (Acp: 6‐aminohexanoic acid) forms nanovesicles at a concentration of 6.9 mg mL^?1. At a concentration of 2.3 mg mL^?1 these vesicular structures completely disappear and nanotubular structures are observed. We have also successfully optimized an intermediate concentration (3.4 mg mL^?1) where an ordered array of fused vesicular structures are formed, which actually leads to the transition from nanovesicles to nanotubes. These vesicular structures are very much sensitive toward metal ions and pH. Biocompatible calcium ions and high pH (10.7) can trigger the rupturing of these nanovesicles. One important property of these nanovesicular structures is the encapsulation of a potent anticancer drug doxorubicin, which can also be released in the presence of calcium ions promising a future use of these nanovesicles as vehicles for carrying biologically important molecules.     

A quick accelerating microwave-assisted sustainable technique: permutated spiro-casing for imaging experiment

Molecular Diversity - A quick access tool for the one-pot, chromatography-free synthesis of the diversified dihydrospiro[indeno[1,2-b]pyridine-4,3′-indoline or...     

An investigation on the structure,spectroscopy, and thermodynamic aspects of clusters: A combined Parallel tempering and DFT based study

The problem of identifying low-energy structures of (n = 1-6) was investigated, and the evaluation of important properties like heat capacity, solvation energy, and vertical detachment energy for each of the clusters was carried out. The problem was handled at two different theoretical levels. First, an adequately chosen empirical potential energy surface was used to account for the major interactions between the constituents of the cluster studied. Once the surface was chosen, the Parallel tempering algorithm was employed to search out the low-energy critical points on this surface, which gave geometries at this level. To refine the structures further, these pre-optimized structures were used as inputs for quantum chemical evaluation to complete the final refinement. To check whether the structures found were reasonable, sensitive properties like heat capacity, solvation energy, and vertical detachment energy were calculated. Then, an effort was made to understand and explain the variations in these properties with change in the cluster size. To understand the process of cluster formation further, thermodynamic aspects like △H (298.15 K), △G (298.15 K), and heat capacity (C_v) changes were also evaluated. Infrared spectroscopic features were also studied to see whether the introduction of the ion caused reasonable shifts compared to a pure water cluster.