Efficient synthesis of naphthodiazacrown ethers

A benign and efficient synthesis of naphthodiazacrown ethers has been described. Reaction of simple dialdehyde precursor with α,ω-diamines followed by sodium borohydride reduction leads to 16-27 membered naphthodiazacrown ethers in 80-90% yields.     

Defining the Determinant-like Function for m by n Matrices Using the Exterior Algebra

In this paper, we present a function called the Determinant-Like Function that generalises the determinant function to m by n matrices using the Clifford algebra C?(V, 0). By definition, this generalisation satisfies the property that the exterior product of its column vectors has a magnitude that equals its determinant-like function if it has more rows than columns. For matrices which have more columns than rows, we make use of another property that the exterior product of its rows has a magnitude that equals the absolute value of its determinant-like function if it has more columns than rows. Defining the sign of this determinant-like function remains an open question.     

Chromatographic Analysis of Bioactive Markers in Vidangarista,an Ayurvedic Polyherbal Formulation

JPC – Journal of Planar Chromatography – Modern TLC - Vidangarista is an ayurvedic polyherbal formulation officially recorded in the Ayurvedic formulary of India and used as an...     

Bleach Enhancement of Mixed Wood Pulp by Xylanase–Laccase Concoction Derived Through Co-culture Strategy

Mixed enzyme preparation having both xylanase and laccase activity was evaluated for its bleach enhancing ability of mixed wood pulp. The enzyme was produced through co-cultivation of mutant Penicillium oxalicum SAU_E-3.510 and Pleurotus ostreatus MTCC 1804 under solid-state fermentation. Bleaching of pulp with mixed enzyme had resulted into a notable decrease in kappa number and increased brightness as compared to xylanase alone. Analysis of bleaching conditions had denoted that 8 IU g⁻¹ of mixed enzyme preparation (xylanase/laccase, 22:1) had led into maximal removal of lignin from pulp when bleaching was performed at 10% pulp consistency (55 °C, pH 9.0) for 3 h. An overall improvement of 21%, 8%, 3%, and 5% respectively in kappa number, brightness, yellowness, and viscosity of pulp was achieved under derived bleaching conditions. Process of enzymatic bleaching was further ascertained by analyzing the changes occurring in polysaccharide and lignin by HPLC and FTIR. The UV absorption spectrum of the compounds released during enzymatic treatment had denoted a characteristic peak at 280 nm, indicating the presence of lignin in released coloring matter. The changes in fiber morphology following enzymatic delignification were studied by scanning electron microscopy.     

IR laser photodeposition of a-Fe/Si films developing nanograins of ferrisilicate, iron disilicide and rare hexagonal iron upon annealing

IR laser-induced gas-phase photolysis of Fe(CO)(5)-SiH(4) mixtures occurs as SiH(4)-photosensitized decomposition of Fe(CO)(5) is accelerated by products of this decomposition and it results in deposition of amorphous Si/Fe nanocomposite films. Analyses of the deposited and subsequently annealed solid films were made by FTIR, Raman and X-ray photoelectron spectroscopy, X-ray diffraction and electron microscopy. The deposited films are amorphous, contain crystalline nanostructures of iron silicide FeSi(2) and undergo atmospheric oxidation in topmost layers to iron oxide and hydrogenated silicon oxide. Upon annealing they develop nanocrystalline structures of ferrisilicate, Fe(1.6)SiO(4), carbon-encaged iron disilicide, FeSi(2), and very rare hexagonal (high-pressure) Fe surviving at ambient conditions. The mechanism of formation of these nanostructures is discussed in terms of gas-phase and solid-phase reactions.     

Polymer Carriers for Anticancer Drugs Targeted to EGF Receptor

A novel actively targeted polymer carrier for anticancer drugs based on an N‐(2‐hydroxypropyl)methacrylamide copolymer (PHPMA) is proposed. An oligopeptide sequence GE7, attached to the polymer, is a specific ligand for the EGF receptor overexpressed on most tumor cells. Co‐attachment of selected chemotherapeutics will therefore lead to formation of tumor‐specific polymer therapeutics, further enhanced by the EPR effect. FACS measurements prove elevated binding activity of the fluorescently labeled PHPMA/GE7 conjugate in EGFR‐rich cells (FaDu, MCF‐7), compared to conjugates of scrambled peptides. Cell lines with low EGFR level (SW620, B16F10) bind the GE7 conjugate significantly less.

     

ArF laser photolytic deposition and thermal modification of an ultrafine chlorohydrocarbon

MW ArF laser irradiation of gaseous cis-dichloroethene results in fast decomposition of this compound and in deposition of solid ultrafine Cl- and H-containing carbonaceous powder which is of interest due to its sub-microscopic structure and possible reactive modification of the C-Cl bonds. The product was characterized by electron microscopy, and FTIR and Raman spectra and it was revealed that HCl, H₂, and C/H fragments are lost and graphitic features are adopted upon heating to 700°C.     

UV laser-induced photolysis of 1,3-disilacyclobutane in oxygen for chemical vapour deposition of nano-sized polyoxocarbosilane films

The multi-pulse ArF laser irradiation into gaseous 1,3-disilacyclobutane–O₂ mixture in excess of buffer gas occurs as non-explosive chemical vapour deposition of solid methylsilicone films, whereas the single-pulse irradiation into the gaseous mixture in the absence of buffer gas results in explosive chemical vapour deposition of solid nano-structured polyoxocarbosilanes poor in hydrogen.     

Evolution of intranuclear collisions at intermediate energies

The experimental data on energy and multiplicity distributions of protons and momentum spectra of deuterons emitted in the reactions of pions and protons of energy ranging from 2.5 to 200 GeV with several nuclei are compared to the calculations based upon two different model approaches: DCM Monte Carlo [3] code and the tube-fireball (TF) model [4]. The results of this confrontation are discussed within the framework of the intranuclear interaction mechanism assumed. A detailed study of the intranuclear scenario presented by the DCM Monte Carlo program gives grounds to build simplified analytic models like the TF which may turn out to be very useful in many practical problems as being of a predictive nature. The text was submitted by the authors in English.