Developmental expression of nitric oxide synthase in the rat diencephalon with special reference to the thalamic paratenial nucleus

Using immunohistochemistry and in situ hybridization the distribution of nitric oxide synthase (NOS) was investigated in the rat brain during pre- and postnatal development. At E15 weak NOS-like immunoreactivity (NOS-LI) could be seen in the differentiation field of the anterior hypothalamus. At E17 strong NOS-LI was observed in the developing neurons of the hypothalamic paraventricular nucleus, supraoptic nucleus, anterodorsal nucleus and lateral hypothalamic areas. In the thalamic paratenial nucleus a strong NOS-LI was observed in these neurons at E17, E18 and P1 with a weaker intensity at P3, P7, P9 and P15, whereas at P30 and in adult rats no NOS-positive neurons could be detected. NOS expression at E17 and P3 was verified by in situ hybridization. These results suggest that NO may have a developmental role at least in one of the regions studied, the thalamic paratenial nucleus.     

Mathematical Model of the Accelerated Cooling of Metal in Thick-Plate Hot Rolling

Metallurgist - The paper describes the issues in predicting the consumer properties of thick-plate pipe products manufactured at the hot rolling mill 5000 of the Magnitogorsk Iron and Steel Works....     

Transient characteristics of reversely switched dynistors in the submicrosecond pulse range

Transient injection processes in reversely switched dynistors (RSDs) operating in a submicrosecond pulse range have been numerically simulated and the output current and voltage characteristics have been calculated. It is shown that, provided a proper choice of parameters of the silicon device structure and external chains, RSDs can be used to switch current pulses with amplitudes up to several dozen kA/cm², total durations of several hundred nanoseconds, and leading edge widths within 50–100 ns. The voltage decreases from the initial level by an order of magnitude already in 15–20 ns, and attains a steady value of 10–25 V during the leading edge time.     

Assessing Parameters of the Accelerator Disk of a Centrifugal Mill Taking into Account Features of Particle Motion on the Disk Surface

A mathematical model of the motion of a single particle on the working surface of the disk (working body) of a centrifugal mill is presented. The model takes into account the influence of the friction force and shape and geometric parameters of the disk on the velocity of the material at the time moment of its detachment from the disk. The boundary values of the angular velocities of the accelerator disks, which depend on the friction force between a piece of rock and the working surface of the disk, are established. Exceeding these values does not lead to an increase in the detachment velocity and the efficiency of grinding, which is confirmed by experimental studies.     

Improvements to Mixing of Natural Gas and Hot-Air Blast in the Air Tuyeres of Blast Furnaces with Thermal Insulation of the Blast Duct

Metallurgist - Using natural gas as an additional fuel in a blast furnace is known to reduce coke consumption during blast-furnace production. In a standard tuyere, the hot blast pushes the natural...     

Development of a Method for the Visualization of the Process of Forming of Curved Profiles in the Software Used for the Numerical Analyses of the Roll Passes

Metallurgist - We propose a method for the visualization of the process of bending in the developed computer-aided system aimed at the design of equipment and tools used in manufacturing of bent...     

Static and dynamic characteristics of antiparallel diode as part of switching power module

A numerical simulation of the operation of a fast antiparallel diode in the switching power module of an autonomous voltage inverter is carried out. The time of turning off the transient and the static and transient heat losses in the diode are calculated as a function of the electrophysical parameters of the semiconductor diode structure.