卷 61, 编号 2 (2018)

An analytical review of the modern state of the development of ion sources with solid electrolytes (superionic conductors) for the aerospace and ion-beam technologies is presented. The methods for synthesis and properties of solid electrolytes, the formation of mobile ions at the “reservoir–electrolyte” interface, the fast-ion transport in a thin electrolyte film under the action of an external electric field, and the processes of ion emission (evaporation) from the surface of the electrolyte into a vacuum at a temperature below the thermionic-emission threshold and an electric-field strength that is lower than that of field-ion emitters are discussed. The operation modes, the design and manufacturing technology of anion and cation sources are described in detail. Methods for improving the performance and the main fields of application, including electrostatic rocket engines (ion microthrusters), for which a matrix solid-state ion–electron source was designed and patented, are analyzed.

A pulsed 55-MeV race-track microtron that was developed and constructed jointly at the Skobeltsyn Institute of Nuclear Physics, Moscow State University and the Lebedev Physical Institute with the participation of Moscow Engineering Physics Institute is described. The results of calculations of the beam dynamics and the main elements of the accelerator are presented, their design is described, and the results of their measurements and adjustment are presented. The technique and results of the accelerator commissioning are described.

⁹⁹Mo/^99mTc generator is a remarkable radionuclide choice for imaging in nuclear medicine, thereby a neutron activator including two different neutron moderators was devised in a cyclotron-based technique. Neutron activator was designed for ⁹⁹Mo production via radiative capture using proton beam of compact cyclotron. Neutron production by a 30 MeV proton beam interacting with tungsten target was considered to drive the activator. Fast neutrons were gradually moderated toward resonance energy range of molybdenum using joint moderators including light and heavy materials. Molybdenum transmutation as a result of neutron absorption was appraised via lead and water moderators, surround the target and a graphite reflector around the moderator region. ⁹⁸Mo spherical samples with different thicknesses were positioned at radial distances from the target inside the diverse regions of the activator. The neuron flux inside the two moderators was comparable as the water rapidly diminished the flux. The greatest ⁹⁹Mo production yield occurred inside the lead region at 10 cm distance equal to 430.39 ± 0.05 MBq/g for 0.2 cm radius of the sample. Results indicated using heavy moderator reduces the neutron-adiabatic probability over ⁹⁸Mo resonance peaks therefore neutron capture improves during transmutation process. In comparison with the reactorbased method, a local method for radioisotope production using small and low-current cyclotrons can decrease the expenditures in nuclear medicine policies due to more safety and commercial usages.

Analog-to-digital converter chips used in the Cockcroft−Walton generators of the forward calorimeter in the PANDA experiment have been tested for radiation hardness in γ-ray and neutrons fields. The radiation hardness of temperature sensors under exposure to a neutron flux has also been investigated.

The design and principle of operation of a high-voltage high-speed switch consisting of two opposite-parallel connected RVU-61 triggered vacuum gaps are described and the results of testing it are provided. The switch is designed to switch capacitor banks with a charging voltage of 0.1–50 kV that operate in the mode of an oscillatory circuit. One specific feature of the switch is the possibility of controlling the duration of the switched pulse, which enables saving energy in the subsequent bank charging.

The calculation, measurements, and testing of a vacuum RF S-band window are described. Vacuum waveguide pillbox-type RF windows at a frequency of 2856 MHz, which were developed and manufactured at the works of the Budker Institute of Nuclear Physics (BINP), make it possible to replace the RF windows of the klystrons that are used in the injection complex of the BINP and can be applied in new designs in the fields of both RF-power sources and accelerator techniques. Tests were performed using 35-MW pulsed power and a pulse duration of 3.8 μs.

Some aspects of the applicability of the magnetic-probe technique in high-power pulsed discharges are analyzed. The influence of an electron beam and an intense X-ray yield of (~1 TW/cm²), which result from the compression of high-current plasma in the interelectrode gap of a Z-pinch discharge, on the correctness of measurements using magnetic-field probes was studied. We considered the use of multilayer shells as a method for protecting the sensing element of a magnetic probe. The results of experimental testing of probes of a new design in experiments with wire assemblies on the Angara-5-1 facility at discharge currents of up to 4 MA are presented. Experiments on the Angara-5-1, PF-3, and PF-1000 high-power electrophysical facilities show the effect of the shape and material of the probe shell on the perturbation of plasma that flows around a probe and, as a consequence, on the accuracy of the magnetic-field measurements.

A compact setup for investigating the cathodoluminescence was created on the basis of a gas diode, a compact GIN-55-01 pulse–periodic generator, and an industrial spectrometer. Under the excitation by a beam of runaway electrons with a pulse duration (full width at half maximum) of ~100 ps, the cathodoluminescence spectra of natural and synthetic diamonds, calcite, cesium iodide, zinc selenide, zirconium dioxide, sapphire, gallium oxide (III), cadmium sulfide, zinc sulfide, calcium fluoride, and other crystals were recorded. The prospects of using gas diodes, which were developed at the Institute of High Current Electronics (Siberian Branch, Russian Academy of Sciences), and pulsers, which were created by the FID-Tekhnologiya Company (St. Petersburg), were shown when studying the properties of pulsed cathodoluminescence.

A measuring system for current deep-level transient spectroscopy of semiconductor diode structures is described. Its distinguishing feature is the ability to measure several relaxation currents (up to eight current dependences for one temperature scanning) at different regimes of deep-level recharging. The structural features of the system for measuring and analyzing the temperature dependence of the relaxation current in semiconductor structures are described.

Aim of this paper is the design of an absorption spectrophotometer based on LED technology presenting several advantages such as high luminous efficiency, reliability, long operating duration, low maintenance and low power consumption besides the reduction of analyte temperature variations which occur if Xenon light source is used. An optical filtering system was realized to detect analyte absorption for each wavelength range selected by proper optical filters; also to characterize filtered light beam in terms of its coherence length, thus correlating measured absorption spectrum with light source characteristics, the Michelson interferometer was used. Realized white LED-based spectrophotometer can be used to monitor air quality in hospital rooms or to detect atmospheric pollution deriving from vehicular traffic and different typology of pollutants (e.g., heavy metals deriving by industrial activities). A PC-interfaced control unit acquires and processes raw data provided by sensors (pressure, temperature, humidity, luminosity) and manages the optical filtering system motion by actuating a stepper motor. Whole system operation was tested and obtained results confirm the proper functioning and correct interaction, through PC terminal, between user and control unit.

A new method for direct measurement of the pressure increase in energetic compositions (propellants, powders, and explosives) upon thermal decay of energetic samples is described. This method is applicable to the control of the decay kinetics of elastic compositions during long-time storage. The testing of this method showed that the error in measuring the pressure increase in the systems under study during long-time storage at a constant temperature and the maximum filling of the reaction container did not exceed 4%.

It is shown that by using electric-field-controlled transistor-type sensing elements with a siliconon-insulator structure as a basis it is possible to develop multichannel and multifunctional sensors with a controllable frequency output. The sensitivities of the described frequency-output sensors of the magnetic field and temperature are as high as 2.2 kHz/mT and 1.5 kHz/°C, respectively.

We consider the conditions for reducing the threshold dose of radiation-gas splitting of a silicon single crystal by using a fixed-energy two-stage irradiation with hydrogen ions in a single production cycle. It has been experimentally established that a well-developed blister structure is formed in a sample in the mode of its two-stage irradiation with hydrogen ions with E = 12.5 keV and a dose of 0.5 × 10¹⁶ cm^–2 at a normal angle of incidence at the first stage and, then, with a dose of 1.0 × 10¹⁶ cm⁻² at an angle of 32° at the second stage (the total dose is 1.5 × 10¹⁶ cm^–2). This structure is similar to the structure in a sample irradiated in the mode of single-stage irradiation to a dose of 5 × 10¹⁶ cm^–2. This fact is the indication that the conditions for more than a threefold decrease in the threshold for the formation of hydrogen blisters in silicon upon twostage irradiation with monoenergetic hydrogen ions in a single production cycle.