Study of the behavior of vver and pwr fuel irradiated in the hbwr reactor (halden,norway)

The methods, techniques, and results of comparative studies of VVER and PWR fuel tested in the HBWR reactor (Norway) are presented. Experimental VVER fuel elements with uranium dioxide fuel were fabricated at the Machine Building Plant (MSZ) (in Elektrostal) using standard technology; the experimental PWR fuel elements were fabricated according to the model specifications. The results obtained made possible a comparative evaluation of the changes in the thermophysical parameters and the heat and radiation resistance of the two types of fuel as well as the kinetics of the gaseous fission products as a function of the heat load and burnup.     

Improving the production of steel grinding balls at AO EVRAZ ZSMK

The production of steel grinding balls is improved by reducing the billet temperature before rolling, reducing the number of balls between the flanges of the quenching drum, and limiting the discharge temperature of the balls from the bunker after self-tempering. The macrostructure of the billet must be improved, and proportional increase in length and speed of the quenching drum is required.     

Kinetics and mechanism of interaction of aluminum and magnesium of Al-Mg-Bi ternary system with water

The kinetics and mechanism of interaction of aluminum and magnesium of an Al-Mg-Bi ternary system with water were obtained using the method of high-temperature volumetry at high pressures and temperatures of 225–325°C. The kinetic parameters of the reaction, i.e., the rate constant, activation energy, and degree of conversion, were calculated and the mechanism of corrosion dissolution of activated by bismuth aluminum and magnesium in water with the release of hydrogen at high rates was suggested. The kinetic parameters during the interaction of aluminum activated by bismuth and magnesium in boehmite (AlOOH), and magnesium hydroxide (Mg(OH)₂) with water with the release of hydrogen at a rate of 3196–4033 l/(m² min) in the investigated temperature range were determined. The nanostructured particles of Al-Mg-Bi alloys were detected using a JSM6490 LV electron microscope (Japan).     

A multichannel power supply for high power magnetrons

The paper describes characteristics and design principles of a multichannel power supply for CW magnetrons with RF power up to 3 kW. An advanced control system implemented in the power supply has resulted in its good operational properties as well as allowed providing adaptive procedures for the regulation of magnetron operation. A modular approach based on utilization of novel electronic components increases reliability and lowers weight and dimensions of the power supply.     

Classification of superconducting cables of power purpose

Classification of low-temperature and high-temperature superconducting cables of direct and alternating current for power purposes based on the traditional and prospective implementation is presented. Results of designing multicore superconducting cables with localized magnetic field, providing maximal critical current density, reducing consumption of superconducting material, cold fluid, and energy losses in cables are reported.     

Optical monitoring of substrate temperature and etching speed of multilayered structures during plasmochemical etching

Using weakly coherent tandem interferometry, the possibility of simultaneous temperature and film thickness measurements in plasmochemical etching processes of silicon on insulator structure is demonstrated. It is shown that changes of the structure’s total optical thickness related to temperature variation can be separated from a change of the physical film thickness. For that purpose we have to take in account changes of zeros interference peak amplitude caused by changes of the interferentional conditions inside the film when its thickness is changing. Temperature measurement precision is ±1°C. Thickness measurement precision is ±10 nm. The results of process monitoring closely correlate with the results of a stair’s profile obtained with a profilometer.     

Stabilizing RNA by the sonochemical formation of RNA nanospheres

Biological macromolecules, including DNA, RNA, and proteins, have intrinsic features that make them potential building blocks for the bottom-up fabrication of nanodevices. Unlike DNA, RNA is a more versatile molecule whose range in the cell is from 21 to thousands of nucleotides and is usually folded into stem and loop structures. RNA is unique in nanoscale fabrication due to its diversity in size, function, and structure. Because gene expression analysis is becoming a clinical reality and there is a need to collect RNA in minute amounts from clinical samples, keeping the RNA intact is a growing challenge. RNA samples are notoriously difficult to handle because of their highly labile nature and tendency to degrade even under controlled RNase-free conditions and maintenance in the cold. Silencing the RNA that induces the RNA interference is viewed as the next generation of therapeutics. The stabilization and delivery of RNA to cells are the major concerns in making siRNAs usable drugs. For the first time, ultrasonic waves are shown to convert native RNA molecules to RNA nanospheres. The creation of the nanobubbles is performed by a one-step reaction. The RNA nanospheres are stable at room temperature for at least one month. Additionally, the nanospheres can be inserted into mammalian cancer cells (U2OS). This research achieves: 1) a solution to RNA storage; and 2) a way to convert RNA molecules to RNA particles. RNA nanosphere formation is a reversible process, and by using denaturing conditions, the RNA can be refolded into intact molecules.     

Grinding of the inner thread without tilt of the tool spindle

A mathematical model of the grinding process for an inner step thread with an abrasive wheel without tilt of the tool spindle is described. The problem of calculation of a shape of a curvilinear part of the profile of the grinding wheel and simulation of thread processing is solved for the evaluation of a possibility of cutting this thread with the required accuracy using a tool of a certain diameter. Examples of calculation of the process parameters for grinding various types of inner thread are shown.     

The isolation and characterisation of a gene encoding superoxide dismutase from Bradyrhizobium sp. (Parasponia) strain ANU289

Bradyrhizobium sp. (Parasponia) strain ANU289 expresses a single Mn-SOD in both the vegetative and symbiotic states. A 500 bp sod-homologous sequence was amplified from genomic DNA of strain ANU289 using PCR. A 1.3 kb SalI fragment was subsequently cloned which contained an ORF, sodA, encoding a 23 Kd protein. This putative SOD shares considerable homology with other Mn-SODs and analysis of the sodA sequence predicts that it is expressed. A lacZ-sodA fusion complemented the SOD-deficiency of E. coli QC779 and resulted in the expression of SOD activity in both mutant and wild type E. coli. We conclude that sodA encodes the Mn-SOD of strain ANU289.