Lattice vibronics of bcc phase metals (Ti,Zr and Hf) at higher temperatures

Ashcroft’s analytic bare ion pseudopotential form factor with a modified Hartree dielectric function has been employed to represent the temperature dependent interionic potential. This potential includes both direct ion-ion interaction and indirect ion-electron-ion interaction with and without the effects of ‘d’ bands, in some scantily studied complexbcc metals vizbcc Ti, Zr and Hf. The ab initio radial and tangential force constants extending out to 15th nearest neighbours are computed for the metals. The said potential is used for predicting the binding energy, elastic constants and phonon dispersion of the above mentioned metals and the results are satisfactorily compared with the corresponding measured data.     

Toroidal hopping of a single hole through the circularly-arrayed naphthyl groups in hexanaphthylbenzene cation radical

Synthesis of a dendritic (soluble) hexanaphthylbenzene derivative is described in which the six naphthyl groups are connected to the central benzene ring in a propeller-shaped arrangement. Observation of multiple oxidation waves in its cyclic voltammogram as well as an intense charge-resonance transition (extending beyond 1600 nm) in its cation radical, generated by laser-flash photolysis using photoexcited chloranil as an oxidant, suggests that a single hole is mobilized via electron transfer (or hopping) over six identical (circularly arrayed) redox centers.     

Kinetics of glass transition and thermal stability of?Se58Ge42?xPbx?(9≤x≤20) glasses

Se₅₈Ge_42−x Pb _x (9≤x≤20) glasses have been prepared using conventional melt quenching technique. Differential Scanning Calorimetric (DSC) measurements show single glass transition and double crystallization, which indicate the occurrence of phase separation in the samples. The phases present in the samples were identified using XRD. The kinetics of the glass transition has been studied in terms of the variation of glass transition temperature with composition and heating rate. In addition to this, activation energy of the glass transition (E _t ) has also been evaluated and its composition dependence is also investigated. The thermal stability of these glasses has been investigated using various stability criteria: Deiztal first glass criterion, ΔT, Saad and Poulain weighted thermal stability, H′ and the S-parameter. The values of these parameters were obtained using various characteristic temperatures such as the glass transition temperature, T _g , the onset temperature of crystallization, T _c , and the peak crystallization temperature, T _p . The values of stability parameters show that the phase corresponding to second crystallization is more stable than the phase corresponding to first one. The stability in terms of the lead (Pb) content has been determined considering the values of stability parameters of the phase corresponding to second peak. It was found that the stability increases with the lead content.     

A novel approach for protein identification from complex cell proteome using modified peptide mass fingerprinting algorithm

A unique peptide based search algorithm for identification of protein mixture using PMF is proposed. The proposed search algorithm utilizes binary search and heapsort programs to generate frequency chart depicting the unique peptides corresponding to all proteins in a proteome. The use of binary search program significantly reduces the time for frequency chart preparation to ～2 s for a proteome comprising ～23 000 proteins. The algorithm was applied to a three‐protein mixture identification, host cell protein (HCP) analysis, and a simulation‐generated data set. It was found that the algorithm could identify at least one unique peptide of a protein even in the presence of fourfold higher concentration of another protein. In addition, two HCPs that are known to be difficult to remove were missed by MS/MS approach and were exclusively identified using the presented algorithm. Thus, the proposed algorithm when used along with standard proteomic approaches present avenues for enhanced protein identification efficiency, particularly for applications such as HCP analysis in biopharmaceutical research, where identification of low‐abundance proteins are generally not achieved due to dynamic range limitations between the target product and HCPs.     

The Role of Torsional Dynamics on Hole and Exciton Stabilization in π‐Stacked Assemblies: Design of Rigid Torsionomers of a Cofacial Bifluorene

Exciton and charge delocalization across π‐stacked assemblies is of importance in biological systems and functional polymeric materials. To examine the requirements for exciton and hole stabilization, cofacial bifluorene ( F 2) torsionomers were designed, synthesized, and characterized: unhindered (model) ^Me F 2, sterically hindered ^tBu F 2, and cyclophane‐like ^C F 2, where fluorenes are locked in a perfect sandwich orientation via two methylene linkers. This set of bichromophores with varied torsional rigidity and orbital overlap shows that exciton stabilization requires a perfect sandwich‐like arrangement, as seen by strong excimeric‐like emission only in ^C F 2 and ^Me F 2. In contrast, hole delocalization is less geometrically restrictive and occurs even in sterically hindered ^tBu F 2, as judged by 160 mV hole stabilization and a near‐IR band in the spectrum of its cation radical. These findings underscore the diverse requirements for charge and energy delocalization across π‐stacked assemblies.     

Fungicidal and bactericidal activity of metal diethyldithiocarbamate fungicides

Copper diethyldithiocarbamate, cadmium diethyldithiocarbamate, lead diethyldithiocarbamate, nickel diethyldithiocarbamate and zinc diethyldithiocarbamate have been synthesized. They have been characterized using TG, DTA, IR spectroscopy, X-ray and atomic absorption spectrophotometry. The thermal conversion of the compounds is 54.36–88% at 1000°C. Their solubility in sodium hydroxide, mineral acids, organic solvents, distilled water and salts solution has been measured. Fungicidal activity of the dithiocarbamates has been tested by well or cup diffusion method using five fungi species. Their activity has also been tested by broth dilution method using six bacterial species. Minimum Inhibitory Concentration (bactericidal) is 6.25–25.00 μg mL⁻¹.     

Photochemical electrocyclization of α,β-unsaturated anilides to give zwitterionic intermediates which eliminate carboxylate and phenolate leaving groups

α,β-Unsaturated anilides bearing allylic leaving groups undergo photochemical electrocyclic ring closure to produce zwitterionic intermediates which eliminate carboxylate and phenolate leaving groups.     

Electron transfer prompted ejection of a tightly bound K(+) from the ethereal cavity of a hexaarylbenzene-based receptor

[structure: see text]. Synthesis of a pair of rotamers (9u/9s) of a hexaarylbenzene derivative containing six (cofacially arranged) electroactive 2,5-dimethoxytolyl groups is described. The toroidal electronic stabilization due to the circular arrangement of aryl groups in 9u/9s leads to the observation of multiple (reversible) oxidation waves and lowering of their E(ox1) by approximately 250 mV relative to model compounds. The binding of K+ to symmetrical rotamer 9s was monitored by an electrochemical method and further confirmed by X-ray crystallography.