A stroll along the gamma

We provide the first in-depth study of the Laguerre interpolation scheme between an arbitrary probability measure and the gamma distribution. We propose new explicit representations for the Laguerre semigroup as well as a new intertwining relation. We use these results to prove a local De Bruijn identity which hold under minimal conditions. We obtain a new proof of the logarithmic Sobolev inequality for the gamma law with $\alpha \ge 1/2$ as well as a new type of HSI inequality linking relative entropy, Stein discrepancy and standardized Fisher information for the gamma law with $\alpha \ge 1/2$.     

Porous Polymers by Emulsion Templating

Highly porous and permeable polymers are produced by polymerisation of the continuous phase of high internal phase emulsions (HIPEs). The morphology and properties of the resulting PolyHIPE materials can be varied, allowing the materials to be optimised for a variety of applications. Void diameter is controlled from 1 to around 100 μm by altering the HIPE stability. Surface areas greater than 700 m²g⁻¹ can be achieved by replacing some of the monomer phase with non-polymerisable solvent, in conjunction with a high crosslink density and the use of a surfactant mixture that limits Ostwald ripening. PolyHIPEs can be produced in a variety of physical forms including large monolithic slabs, rods and flat relatively thin membranes. The materials are currently under investigation for use as electrochemical sensor membrane substrates and as porous matrices for cell culture.     

Optical rotatory dispersion of indole alkaloids from the yohimban, corynanthean, and quebrachamine groups

It has been shown that optical rotatory dispersion curves can be used to determin- the absolute stereochemistry at C(3) of indole alkaloids of the yohimban and corynane thean types. This is dependent on the absence of strong chromophores other than that of the aromatic system.     

Synthesis of the 3-methyl and 4-methyl derivatives of 3-amino-3,4-dihydro-1-hydroxycarbostyril and related compounds

The 3-methyl and 4-methyl derivatives of 3-amino-3,4-dihydro-1-hydroxycarbostyril were synthesized by the reductive cyclization of α-methyl-β-(o-nitrophenyl)alanine and α-amino-β-(o-nitrophenyl)butyric acid hydrohalides, respectively, under conditions of catalytic hydrogenation in acidic solution. The free bases of the latter two o-nitroaromatic amino acids were also catalytically hydrogenated under neutral conditions to yield the respective α-methyl-β-(o-aminophenyl)alanine and α-amino-β-(o-aminophenyl)butyric acid which were converted to the corresponding lactams, 3-methyl- and 4-methyl-3-amino-3,4-dihydrocarbostyrils. α-Methyl-β-(o-nitrophenyl)alanine was obtained by acid hydrolysis of 5-methy)-5-(o-nitrobenzyl)hydantoin which was prepared by treatment of o-nitrophenylacetone with potassium cyanide and ammonium carbonate. α-Amino-β-(o-nitrophenyl)butyric acid was synthesized by condensation of α-bromo-o-nitroethylbenzene with diethyl acetamidomalonate, followed by acid hydrolysis of the condensation product. The 4-methylated compounds were obtained as synthetic mixtures of two diasteromeric racemates in nearly the same amounts as shown by nmr spectral analysis. Unlike the demethylated parent compound, 3-amino-3,4-dihydro-1-hydroxycarbostyril, neither the 3-methyl nor 4-methyl analog was found to possess any antibacterial activity.     

Nuclear orientation — Pulsed magnetic resonance studies of60Co nuclei in iron

The observation of nuclear magnetic resonance of oriented⁶⁰Co nuclei in iron using the techniques of pulsed single passages and single unswept radiofrequency pulses is reported. For large rf fields resonant destructions as high as 80% of the -radiation anisotropy were observed.     

Modeling of RGDC film parameters using X-ray photoelectron spectroscopy

Immobilization of peptides on surfaces is a common method to investigate biological response to biomaterials for the development of improved tissue engineering constructs. Peptide immobilization can be achieved by either physical adsorption or covalent attachment on the surface. In this work, the RGDC peptide was covalently immobilized to alumina substrate for investigation of bone cell response. An understanding of RGDC film formation is necessary for further biological characterization. Thus, X-ray photoelectron spectroscopy was used to chemically characterize these films. These data were further utilized to calculate RGDC film thickness, density, and coverage, which are essential for understanding bone cell interactions with the underlying films and substrate.     

An Investigation into the Materials Handling System of a Fabrication Works

A materials handling system was required for a projected fabrication works. Detailed time studies were made of overhead cranes handling similar material, and the information thus obtained was analysed, leading to improved understanding of the operation of the cranes and hence to measures for increasing their effectiveness. The same time studies were used as a basis for simulating the materials handling system in the projected works on an English Electric “DEUCE” computer. By simulating various combinations of handling equipment a suitable solution was obtained and is now in successful operation.     

Resonance Raman spectra of carbon nanotubes by cross-polarized light

Resonance Raman studies on single wall carbon nanotubes (SWNTs) show that resonance with cross polarized light, i.e., with the E(mu,mu+/-1) van Hove singularities in the joint density of states needs to be taken into account when analyzing the Raman and optical absorption spectra from isolated SWNTs. This study is performed by analyzing the polarization, laser energy, and diameter dependence of two Raman features, the tangential modes (G band) and a second-order mode (G' band), at the isolated SWNT level.