95 research outputs found
Modernization of clamping unit of draft of endosurgical monopolar forceps
© Published under licence by IOP Publishing Ltd. The object of research is the plasma-electrolytic processing, namely the influence of area ratio of the anode and the cathode to the parameters of the process. Defined area ratio anode to cathode, at which the discharge burning occurs on the cathode, on the anode or on the both electrodes simultaneously. Determine the required ratio of the electrodes (S1 ≥ 2 S2) for discharge burning of the electrode S2
Frontiers, challenges, and solutions in modeling of swift heavy ion effects in materials
Since a few breakthroughs in the fundamental understanding of the effects of
swift heavy ions (SHI) decelerating in the electronic stopping regime in the
matter have been achieved in the last decade, it motivated us to review the
state-of-the-art approaches in the modeling of SHI effects. The SHI track
kinetics occurs via several well-separated stages: from attoseconds in
ion-impact ionization depositing energy in a target, to femtoseconds of
electron transport and hole cascades, to picoseconds of lattice excitation and
response, to nanoseconds of atomic relaxation, and even longer macroscopic
reaction. Each stage requires its own approaches for quantitative description.
We discuss that understanding the links between the stages makes it possible to
describe the entire track kinetics within a multiscale model without fitting
procedures. The review focuses on the underlying physical mechanisms of each
process, the dominant effects they produce, and the limitations of the existing
approaches as well as various numerical techniques implementing these models.
It provides an overview of ab-initio-based modeling of the evolution of the
electronic properties; Monte Carlo simulations of nonequilibrium electronic
transport; molecular dynamics modeling of atomic reaction on the surface and in
the bulk; kinetic Mote Carlo of atomic defect kinetics; finite-difference
methods of tracks interaction with chemical solvents describing etching
kinetics. We outline the modern methods that couple these approaches into
multiscale multidisciplinary models and point to their bottlenecks, strengths,
and weaknesses. The analysis is accompanied by examples of important results
improving the understanding of track formation in various materials.
Summarizing the most recent advances in the field of the track formation
process, the review delivers a comprehensive picture and detailed understanding
of the phenomena.Comment: to be submitte
Method of computer-aided conceptual design of Land remote sensing spacecraft with regard to target efficiency parameters
LECラットにおけるポルフィリン代謝異常について = 第一銅メタロチオネイン由来黄橙蛍光の可視化検出とポルフィリン代謝異常の発見
Amount of sampling of analyzed parameters of layers of the basic productive sediments are given. Differentiated multiparametric models of Devonian sediments are considered. Discriminant functions for delimitation of subgroups of Devonian sediments are given
Analytical Solution for the Current Distribution in Multistrand Superconducting Cables
Current distribution in multistrand superconducting cables can be a major concern for stability in superconducting magnets and for field quality in particle accelerator magnets. In this paper we describe multistrand superconducting cables by means of a distributed parameters circuit model. We derive a system of partial differential equations governing current distribution in the cable and we give the analytical solution of the general system. We then specialize the general solution to the particular case of uniform cable properties. In the particular case of a two-strand cable, we show that the analytical solution presented here is identical to the one already available in the literature. For a cable made of N equal strands we give a closed form solution that to our knowledge was never presented before. We finally validate the analytical solution by comparison to numerical results in the case of a step-like spatial distribution of the magnetic field over a short Rutherford cable, both in transient and steady state conditions
Hybrid Molecules Based on Fullerene C60 and Spiropyrans – Perspective Chemo- and Photosensors
This work was fulfilled within the budget topic (AAAA-A17-117012610065-2), and was financially supported by the Ministry of Education and Science of Russian Federation (Project № МК-3058.2018.3, NSh-5240.2018.3)
Fullerene Chemistry: a New Reaction for the Synthesis of Perspective Semiconductor Materials for Organic Electronics
This work was financially supported by Russian Foundation for Basic Research (Project № 17-03-00120) and Russian Science Foundation (Project № 18-73-00084)
Molecular Design of New Hybrid Systems Based on Fullerenes and Norbornadienes
This work was fulfilled within the budget topic (AAAA-A17-117012610065-2), and financially supported by Russian Foundation for Basic Research (Project № 17-03-00120)
Extracorporeal ultrasound exposure by the low-frequency acoustic amplitude-modulated signal on a ureteral stent for preventing its incrustation: experimental determination of optimal application points
Introduction. Incrustation and biofilms formation on the surface of ureteral stents are still the most significant complications of internal drainage of the upper urinary tract. There are much researchers conducted to combat these complications. The lack of a solution to this problem affects the ultimate results of treatment and economic losses. The issue of impact by physical methods on the ureteral stent, particularly the use of extracorporeal ultrasound acoustic exposure remains, promising and poorly covered.Purpose of the study. To determine the optimal application points of extracorporeal acoustic exposure by the low-frequency ultrasonic amplitude-modulated signal on a ureteral stent in an experiment.Materials and methods. The original device was designed. The main principle of its operation is the generation of an amplitude-modulated ultrasonic signal in two modes: pulsed and permanent. A sexually mature mongrel dog was an experimental animal. The ureteral stent was placed by laparotomy and cystotomy. Intraoperatively, the emitter of the developed device was applied to the skin of the animal, according to the previously indicated topographic and anatomical landmarks. At the same time, an ultrasonic wave noise analyzer was applied through the laparotomy wound to the appropriate level of the ureter. Measurements of ultrasound intensity indicators were performed three times in two operating modes of the device.Results. Pulsed mode: for the ureteral upper third, the highest ultrasonic intensity (123.67 dB) was achieved along the posterior axillary line. For the ureteral middle third, the best ultrasound intensity (115 dB) was obtained by the posterior axillary line. For the ureteral lower third, the highest ultrasound intensity (113.67 dB) was noted along the middle axillary line.Permanent mode: the best ultrasonic intensity in the projection of the ureteral upper, middle, and lower thirds was achieved along the posterior axillary line and was 118.67 dB, 117 dB and 116.67 dB, accordingly. However, there was an excessive heat effect, manifested by hyperemia and hyperthermia of the animal's skin, fascicular muscle contractions during the instrument functioned in the permanent mode, which can potentially lead to thermal burns and intolerance to the procedure.Conclusion. The pulsed mode of the device function is most safe. The optimal application points of the instrument emitter for the ureteral upper and middle thirds is the posterior axillary line, and for the ureteral lower third is the middle axillary line
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