Table of contents

N N Potrakhov, A Yu Gryaznov, A A Lisenkov and D K Kostrin

Department of electronic instruments and devices, Saint Petersburg Electrotechnical University "LETI", 197376, Saint Petersburg, Russia

E-mail: kzhamova@gmail.com

Abstract. In this preface key features of the 4th International Conference on X-ray and Electrovacuum Technique that was held on 23–24 November 2017 in Saint Petersburg, Russia are discussed.

On 23–24 November 2017 the representatives of the leading manufacturers of X-ray equipment, universities and research organizations gathered in the walls of the Saint Petersburg Electrotechnical University "LETI" to discuss the latest ideas, developments and achievements in the industry.

The organizer of the 4th International Conference on X-ray and Electrovacuum Technique was Saint Petersburg Electrotechnical University "LETI" with the support of CJSC "Svetlana-X-Ray", OJSC SPC "Burevestnik", CJSC "ELTECH-Med", Saint Petersburg Scientific and Research Institute of Radiation Hygiene n. a. Professor P. V. Ramzaev, Moscow State Technical University of Radioengineering, Electronics and Automation, All-Russian Scientific, Research and Test Institute of Medical Equipment, CJSC "SRPC Elektron", CJSC "AMICO", LLC "Diagnostika-M", CJSC "Medical Technologies Ltd", LLC "Spektroflesh", LLC "Sintez NPF", LLC "Flash electronics".

All papers published in this volume of Journal of Physics: Conference Series have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

The paper considers the main types of defects encountered in products made of polymer composite materials for aviation use. The analysis of existing methods of nondestructive testing is carried out, features of their application are considered taking into account design features, geometrical parameters and internal structure of objects of inspection. The advantages and disadvantages of the considered methods of nondestructive testing used in industrial production are shown.

The technology of welding parts of different thicknesses from various materials is improved, which is why the range of applied types and methods of welding is constantly expanding. In this regard, the issue of monitoring welded joints is particularly acute. The goal was: to develop a method of non-destructive radiographic inspection of point welds with a high accuracy rating of its quality.

X-ray methods for nondestructive control take the priority place if necessary to exercise quality control of a product, to define presence of defects and to execute expert researches. In the present work, an attempt is made to systematize some features in the design and construction of installations for X-ray non-destructive control using the example of developments conducted at St. Petersburg State Electrotechnical University "LETI".

The paper presents the description of the investigation of x-ray tube cathode emitters made of refractory metals by diffusion welding. The weld seam structure has been analyzed. Comparison of the emissivity characteristics of three-layer Ta–W–Ta and Nb–W–Nb cathode emitters has been made.

In this paper the model of X-ray seeds separator is described. The main parameters of the seed separator are determined. The operating modes of the X-ray apparatus were determined; with these modes the greatest contrast of the image was achieved. For the research, seeds of almost 40 different plant species were selected. For each type of seed, the optimal parameters of the imaging were calculated; also during the experimental studies the parameters were checked.

The aim of the current study was to evaluate the possibility of the implementation of LDCT for the screening for lung cancer and tuberculosis in a typical general hospital practice. Diagnostic and economic effectiveness, patient doses and the corresponding radiation risks for LDCT were compared with the existing digital chest screening radiography. The results of the study indicate that the implementation of LDCT allowed verifying false-positive cases or providing additional excessive diagnostic information, but did not significantly improve the sensitivity of screening. Per capita costs for LDCT were higher compared to digital radiography up to a factor of 12; corresponding radiation risk – by a factor of 4. Hence, it was considered unjustified to implement LDCT in a general practice hospital.

The advantages of using the method of microfocus radiography in the non-destructive testing of aviation products are considered in the paper, using the example of a circular beam of a U-shaped profile made of polymer composite materials. The basic types of characteristic defects of parts arising in such a type are described both in the process of their manufacture and in the process of their exploitation, namely interlayer delaminations, pores and folds. Peculiarities of obtaining pseudo-volumetric images, which allow to increase the informativity about the structure of the object of control, as well as to identify the arising heterogeneities are given. A model of a robotic system is described that makes it possible to realize a small or multi-angle survey scheme, and, in particular, to carry out tomographic studies.

Despite obvious drawbacks of the resonant converter, such as complicated calculation, increased size and weight of the device, deviations of the circuit parameters from product to product, the resonant converter shows significant advantages in comparison with other. The task was to design the generator, which is built on a resonant topology.

Recent advances in the field of high-frequency power schemes for X-ray devices allow the creation of high-resolution instruments. At the department of electronic devices and Equipment of the St. Petersburg State Electrotechnical University, a model of a microfocus computer tomograph was developed. Used equipment allows to receive projection data with an increase up to 100 times. A distinctive feature of the device is the possibility of implementing various schemes for obtaining projection data.

X-ray non-destructive testing is an integral part of any modern industrial production. Microfocus X-ray sources make it possible to obtain projected images with an increased spatial resolution by using a direct geometric magnification during the survey. On the basis of the St. Petersburg State Electrotechnical University staff of the department of electronic devices and equipment has been designed model of microfocus X-ray computed tomography.

In this work the effect of X-ray radiation on the operation of integrated circuits of the measurement equipment is discussed. The results of the calculations of a shielding system, allowing using integrated circuits with a high degree of integration in the vicinity of the X-ray source, are shown. The results of the verification of two measurement devices that was used for more than five years in the facility for training and testing of X-ray tubes are presented.

At the present time, the basis of instrumental diagnostics of atelectasis is lung radiography. In the case of preterm infants, it should be performed immediately after birth, and then regularly throughout the entire nursing period. The purpose of the project, within the framework of which this development is carried out, is the creation of an original domestic digital low-dose technology for X-ray examinations in neonatology, including in non-stationary conditions.

Modification of the surface properties of the materials of electrodes or deposition of protective coatings on them are the most effective ways to increase the service life and reliability of electrovacuum devices. Very often for these tasks operations of the carbiding of details are used. In this work results of direct carbiding of W and Mo, carried out in a mixture of the hydrogen stream and the carbon-containing gas on a technological installation of a flow type, are discussed.

In the present work is proposed the design of special liquid phantom for assessing the accuracy of quantitative densitometric data. Also are represented the dependencies between the measured bone mineral density values and the given values for different X-ray based densitometry techniques. Shown linear graphs make it possible to introduce correction factors to increase the accuracy of BMD measurement by QCT, DXA and DECT methods, and to use them for standardization and comparison of measurements.

Usage of the gas discharge in science and engineering is discussed. Application examples of the compact gas-discharge tubes in the X-ray devices and low voltage instrumentation appliances for the surge protection are presented.

In this paper microelectronic devices digital X-ray image processing method development is described. The main steps of the algorithm work are presented. The results of using the algorithm for improving the printed circuit board image are shown

This report presents the development of a miniature ionizing and thermal radiation source for oncological diseases treatment namely the inward parts of the body. This source can be placed next to the tumor inside of the body. This report is only about methods and devices for the intracavitary therapy. Irradiation by external sources wasn't considered in our investigation.

In this paper an analytical model of a high-current form of a low-pressure glow discharge in a cylindrical magnetron is presented. Conditions of discharge self-sustainment, allowing to obtain a quantitative estimation of the discharge voltage were found. Were defined the critical values of the magnetic field and residual gas pressure below which the existence of this type of discharge is impossible. It is shown that the emission of fast electrons from the discharge gap changes the conditions of the discharge.

In this work the features of using the dosimetric devices in the registration of pulsed X-ray radiation are discussed. The dose rate in the pulse mode can reach very high values, while the average value of the dose rate during the operation of the apparatus will be several orders of magnitude lower.

The article deals with the problem of implementing one-way object control with the help of X-ray radiation. Various geometries and materials of radiation detectors are considered. The efficiency of detection of scattered radiation by means of inorganic and organic scintillation detectors with various effective atomic numbers is estimated. Calculations and experiments to determine the signal-to-noise ratio for scanning systems with registration of the radiation beam reflected from the object were carried out taking into account dynamic blurring. Methods for manufacturing detectors that increase the collection efficiency of secondary low-energy quanta formed in the body of the scintillator and reduce the overall dimensions structure are considered. The conditions for achieving the maximum of the efficiency of detection of light photons are determined and the designs proposed for their practical realization.