Extractive Properties of Synergistic Mixtures of Dipicolinic Acid Diamides and Chlorinated Cobalt Dicarbollide

Extraction of Cs, Sr, Eu, U, Np, and Am with mixtures of dipicolinic acid diamides with chlorinated cobalt dicarbollide was studied. A synergistic effect was revealed.     

An Acoustic Converter Used to Measure Ionizing Radiation Energy Loss

A monitor is proposed based on ultrasonic production when ionizing radiation passes through a medium. The recording element is a 0.2 mm aluminum plate mounted in a ceramic acoustic converter AC in the form of a wedge of thickness 2 mm. The low plate thickness minimizes the beam parameter distortion, while special technology used in the AC provides high sensitivity. The device has been calibrated in the proton beam from the ITEP accelerator at 200 MeV with 2·10⁹–6·10¹⁰ particles in a pulse and a pulse length of 70 nsec.     

An investigation of sugar extraction methods and the use of microwave power for date syrup processing: efficiency and color related considerations.

This study investigates the effect of extraction methods on the color of date syrup and the potential use of microwave power for syrup processing. Sugar solutions were extracted from dates by boiling, soaking and blending. Color and sugar content of the extracted solutions were measured, and the percentage of sugar extracted form the total fruit sugar determined. Boiling was found to be the most efficient method of extraction whereby 74% of total samples sugar was extracted. In contrast, only 54.2% of fruit sugar was extracted by blending and 42% by soaking. In addition, solutions extracted by soaking and blending had a foaming problem in the subsequent concentration process. The extraction method had no effect on the product final color. The extracted solution was concentrated using two heating methods: conventional and microwave heating at a 600 W capacity and a frequency of 2450 MHz applied at three power levels: 10, 7, and 6. In the heating process, 180 minutes were needed to achieve a 77% degrees Brix using convective heating, while it took 81, 138, and 166 minutes of microwave heating at power level 10, 7, and 6, respectively to achieve the same concentration. Water activity of the syrup was measured within a sugar content range of 50 to 80% degrees Brix and the sugar concentration at which the product is shelf stable was determined at 76%.     

Reactions Between Ingredients in Binary Silicate Glasses

It is demonstrated that the density of binary glasses upon variation of the molar content of the modifier in their compositions obeys a parabolic dependence, whose parameters can be used to estimate the extent and type of reactions between the components. The reaction parameters in glasses that are prone to liquation are lower by an order of magnitude and have the negative sign.     

Modeling of the Solubility of Solid High-Molecular-Weight Organic Substances in Supercritical Fluids

A method is proposed to calculate the solubility of solid high-molecular-weight substances in organic supercritical fluids on the basis of the Soave and Peng–Robinson equations of state. The mixing rules are modified taking into account the Gibbs energy of mixing calculated for a particular equation of state. The accuracy of calculation of the concentration of the substance dissolved in supercritical fluids is analyzed for different mixing rules. The modeling results are compared with observed data.     

Enhanced Photoelectrochemistry in CdS/Au Nanoparticle Bilayers

Three different configurations of Au‐nanoparticle/CdS‐nanoparticle arrays are organized on Au/quartz electrodes for enhanced photocurrent generation. In one configuration, Au‐nanoparticles are covalently linked to the electrode and the CdS‐nanoparticles are covalently linked to the bare Au‐nanoparticle assembly. The resulting photocurrent, φ = 7.5 %, is ca. 9‐fold higher than the photocurrent originating from a CdS‐nanoparticle layer that lacks the Au‐nanoparticles, φ = 0.8 %. The enhanced photocurrent in the Au/CdS nanoparticle array is attributed to effective charge separation of the electron–hole pair by the injection of conduction‐band electrons from the CdS‐ to the Au‐nanoparticles. Two other configurations involving electrostatically stabilized bipyridinium‐crosslinked Au/CdS or CdS/Au nanoparticle arrays were assembled on the Au/quartz crystal. The photocurrent quantum yields in the two systems are φ = 10 % and φ = 5 %, respectively. The photocurrents in control systems that include electrostatically bridged Au/CdS or CdS/Au nanoparticles by oligocationic units that lack electron‐acceptor units are substantially lower than the values observed in the analogous bipyridinium‐bridged systems. The enhanced photocurrents in the bipyridinium‐crosslinked systems is attributed to the stepwise electron transfer of conduction‐band electrons to the Au‐nanoparticles by the bipyridinium relay bridge, a process that stabilizes the electron–hole pair against recombination and leads to effective charge separation.     

X-Ray Study of the Effect of Heat on the Structural Parameters of Armos Fibres

In studying a series of fibre samples spun in steady-state conditions, the following was found: as a function of the conditions of processing Armos fibre, two structural modifications of the polymer can form; intensive crystallization of the modification corresponding to the 28.7° reflection begins in heat treatment above 220°C; above 320°C, intensive crystallization of the modification corresponding to the 14.25° reflection is observed; at 360°C, symbatic enhancement of the intensities of both reflections with a weak change in the other structural parameters of the fibre is observed.