A mechanical neutron monochromator for a small-angle scattering spectrometer at the SAFARI-I reactor

A mechanical monochromator of slow neutrons that is intended for the use in a small-angle neutron scattering spectrometer constructed on a neutron beam of the SAFARI-I reactor (NECSA, South Africa) is described.     

Measurement of cold neutron spectra using a model cryogenic moderator of the IBR-2M reactor

The method and results of an experiment to determine the cold neutron spectrum from solid mesitylene at moderator temperatures of 10–50 K are presented. This study was performed at the DIN-2PI spectrometer of the IBR-2 reactor. The objective of the study was to verify the system of constants used in the Monte Carlo simulation of cryogenic neutron moderators of the IBR-2M reactor and to obtain the cold neutron yield as a function of the moderator temperature. Satisfactory agreement between the experimental and calculated neutron spectra at a mesitylene temperature of 20 K has been obtained; the ratio of cold neutron intensities at 10 and 50 K is ∼1.8.     

Blocked Diisocyanate as a Promoter of Rubber Adhesion to Brass-Plated Metal Cord

Conditions for preparing boron-containing blocked diisocyanate in a melt of blocking agents at low temperatures in the absence of solvents were examined.     

Direct stratospheric measurements of charges and energies of Primary Cosmic Rays in the range of 10<Superscript>13</Superscript> − 10<Superscript>15</Superscript> eV (CROSS Project)

The CROSS (Cosmic Rays Over Spectrum Steepening) experiment is aimed at direct measurements of masses and energies of primary cosmic ray (PCR) nuclei in the range of 10¹³ ? 10¹⁵ eV near the break in the PCR energy spectrum. The experimental equipment includes a balloon ionization spectrometer consisting of X-ray transition radiation generators interlaid with thin-wall proportional chambers.     

Investigation of the microstructure of activated carbons by the small-angle slow neutron scattering method

The porosity characteristics of the SKT-3 activated carbon (both pure and impregnated with a specific impregnator that increases the carbon absorbability to iodine) have been studied using small-angle neutron scattering. It has been established that the impregnation with an impregnator slightly affects the porosity characteristics of the SKT-3 carbon. The average size of the scattering object is estimated as R ～ 500 Å.     

Software for Efficient Chemical Technologies for Processing of Apatite–Nepheline Ore Waste

Doklady Chemistry - Aspects of the methodological support of digital twins were presented by the example of the chemical and energy engineering process of phosphorus production from...     

Statistical aspects of the failure of organic-fiber-reinforced plastics

Conclusions Dispersion of the strength of filaments and of the Weibull coefficient leads to a drop in strength of a strand compared with the strength of the components when the adhesion by gluing together does not amount to 2–5%. The drop in strength is determined by the dispersion of strength which depends on the length of the tested specimens.Gluing together of the fibers in filaments changes the nature of the load diagrams - of a filament when its length exceeds ₀. A consequence is that the mechanism of rupture of the strand changes, and this leads to an additional drop of its strength. When specimens are 500 mm long, the drop in strength of the strand compared with the mean strength of the filaments amounts to 10%.Because of the dispersion of the Weibull coefficient, the strength of filaments does not correspond exactly to the strength of the microplastic obtained from these filaments. When there is dispersion of the strength of the filaments, failure of the plastic proceeds by failure of the microplastics as a whole.Gluing together of fibers has a double effect on the strength of the material: increased degree of gluing together of the fibers reduces the noneffective length from ₀ to 0.4–0.5 mm, and this leads to an increase of approximately 50% of the strength of the microplastic; increased gluing together leads to a change in the mechanism of failure of the strand and of the organic-fiber-plastic made from it if there is dispersion of the strength of the component filaments, and this reduces the strength of the material in accordance with (3) (by 12–14% in our case). The longitudinal instability of the properties of the filament leads to an additional drop in strength of the material by 4.5%.Translated from Mekhanika Kompozitnykh Materialov, No. 6, pp. 1011–1017, November, 1984.