Cleaning of niobium surface by plasma of diffuse discharge at atmospheric pressure

Elements composition of niobium surface before and after plasma treatment by runaway electron preionized diffuse discharge was investigated in atmospheric pressure nitrogen flow by means of an Auger electron spectroscopy. Surface characterizations obtained from Auger spectra show that plasma treatment by diffuse discharge after exposure of 120000 pulses provides ultrafine surface cleaning from carbon contamination. Moreover, the surface free energy of the treated specimens increased up to 3 times, that improve its adhesion property

INFLUENCE OF OZONE THERAPY AND UTROZHESTAN ON HORMONE PRODUCING FUNCTION OF FETOPLACENTAL COMPLEX AT THE THREATENING PREMATURE BIRTH AND FETOPLACENTAL INSUFFICIENCY

We researched hormonal function of fetoplacental complex (FPC) in 180 pregnant women with threatening premature birth and chronic fetoplacental insufficiency including 90 patients who received ozone therapy in combination with Utrozhestan, 90 pregnant women who received traditional therapy, and 51 woman with an uncomplicated pregnancy (control group). Corrective and. stimulating effect of ozone therapy and. Utrozhestan. on hormonal function fetoplacental complex was revealed

Application of surfacing using consumable electrode with an additional filler wire to ensure the required operational properties of pipeline valves

A promising way to ensure the required operational properties of pipeline valves with a significant increase in productivity and quality of surfacing during its manufacture is the introduction of anti-corrosion surfacing technologies using a consumable electrode with the supply of an additional filler wire. A solution to the optimization problem of the proposed surfacing technology is complicated by a large number of its parameters, therefor the task was solved in stages. At the first stage, the parameters of the arc interaction between the electrode and filler wire was determined, and at the second - the specific features of the formation of the surfacing bath with such interaction. A virtual study of the process of surfacing with Inconel 625 wires in argon on steel 09G2S was carried out. The influence of the thermal effect of the deposition mode parameters on the main metal is determined. It has been established that, due to the fact that the heat flux in the main metal is created mainly by the droplet stream of the deposited metal from the main arc at high currents, the diameter of the electrode wire guaranteeing its burning should be larger than the filler wire. © Published under licence by IOP Publishing Ltd

Double-sided arc welding with multiple electrodes of vertical joints of steel tanks

The increase of the welding productivity is still of immediate interest, which in turn requires the development and implementation of more high-performance welding methods that ensure a consistently high quality of welded joints. One of the ways to further increase the productivity of arc welding processes in the construction of tanks is the industrial use of automatic double-sided arc welding with multiple electrodes in separate weld pools. To establish the relationship between the parameters of the welding mode, energy characteristics, as well as the distance between the torches and their angle of inclination relative to the groove, a physical and mathematical model of the production of the welding joint when four arcs participate in pairs from both sides of the joint has been developed. Thus, computer modeling showed that during weld formation with the movement of the electrode down (vertical down), the possibility of supplying each pair of arcs with pulsed current should be taken into account. During groove filling with the movement of the electrodes up (vertical up), their lateral oscillations and delays at the edges should be carried out according to an aperiodic law in order to minimize the effects of 'magnetic blow'. © Published under licence by IOP Publishing Ltd

Comprehensive analysis of the results of surgical treatment of patients with degenerative diseases of the lumbar spine using rigid fixation systems

Introduction. According to the literature, the development of adjacent-level syndrome 10 years after posterior rigid stabilization is noted in 6.7–80 % of patients, of which 24 % require revision surgery.The aim: to conduct a comprehensive analysis of the results of surgical treatment of patients with degenerative diseases of the lumbar spine using rigid fixation systems.Materials and methods. A multicenter retrospective study of the results of surgical treatment of 268 patients with degenerative-dystrophic diseases of the lumbar spine, who underwent mono- or bisegmental decompression-stabilizing intervention with the implementation of the TLIF (Transforaminal Lumbar Interbody Fusion) technique and open transpedicular rigid fixation, was conducted. The study included radiography, MRI and CT (in 2-energy mode) of intervertebral discs and isolated facet degeneration of the upper adjacent level.Results and discussion. The combination of the initial degeneration of the adjacent spinal motion segment in the form of disc degeneration of grade III and higher according to Pfirrmann with threshold values of the density of the outer cartilaginous plate from 161.7 ± 18.8 to 164.8 ± 14.2 HU, the density of the outer facet – from 702.43 ± 12.3 to 713.65 ± 13.6 HU and the density of the inner facet – from 580.5 ± 11.6 to 582.1 ± 15.1 HU, as well as with signs of segmental instability of the adjacent segment can be considered as risk factors for the development of its degeneration. With the progression of degeneration of the upper intervertebral disc, revision interventions were performed within 12–60 months after surgery.Conclusion. Bisegmental stabilization with signs of initial degeneration in the intervertebral disc and facet joints in the upper segment has proven its clinical and instrumental effectiveness in the period of 36 months and reduces the risks of developing degenerative disease of the adjacent disc

Surface hardening of stainless steel by runaway electronspreionized diffuse discharge in air atmosphere

In this paper we present microhardness measurements of stainless steel surface treated by diffuse discharge in air atmosphere. The cleaning from carbon in comparison to the initial sample was observed at a depth exceeding 20 nm. The oxygen concentration was also increased in comparison to that in the initial sample at a depth of up to about 50 nm. Comparative analysis shows that after treatment the microhardness of stainless steel surface increased in 2 times due to interaction of near-surface layers with product of plasma chemical reactions produced in diffuse discharge

Study of the process e+e−→ppˉe^+e^-\to p\bar{p} in the c.m. energy range from threshold to 2 GeV with the CMD-3 detector

Using a data sample of 6.8 pb$^{-1}$ collected with the CMD-3 detector at the VEPP-2000 $e^+e^-$ collider we select about 2700 events of the $e^+e^- \to p\bar{p}$ process and measure its cross section at 12 energy ponts with about 6\% systematic uncertainty. From the angular distribution of produced nucleons we obtain the ratio $|G_{E}/G_{M}| = 1.49 \pm 0.23 \pm 0.30$

Measurement of the e+e−→K+K−π+π−e^+e^- \to K^+K^-\pi^+\pi^- cross section with the CMD-3 detector at the VEPP-2000 collider

The process $e^+e^- \to K^+K^-\pi^+\pi^-$ has been studied in the center-of-mass energy range from 1500 to 2000\,MeV using a data sample of 23 pb$^{-1}$ collected with the CMD-3 detector at the VEPP-2000 $e^+e^-$ collider. Using about 24000 selected events, the $e^+e^- \to K^+K^-\pi^+\pi^-$ cross section has been measured with a systematic uncertainty decreasing from 11.7\% at 1500-1600\,MeV to 6.1\% above 1800\,MeV. A preliminary study of $K^+K^-\pi^+\pi^-$ production dynamics has been performed

Morphofunctional reorganization of plantar aponeurosis in experimental modeling of fasciopathy by synthetic analogue of prostaglandin E1

Foundation. Chronic plantar fasciopathic pain syndrome is a pathology that significantly affects the quality of life of patients of all age categories. Insufficient knowledge of the etiological and pathogenetic factors in the development of fasciopathies explains the multiplicity, and sometimes inconsistency, of conservative and surgical treatment regimens. The choice of the optimal variant of therapeutic or surgical intervention may be associated with experimental modeling of fasciopathies and the study of the dynamics of the pathological process.The aim. To study the morphological changes in structures identical to the human plantar aponeurosis in experimental modeling of fasciopathy in animals.Research methods. The material for the study was fragments of the tendonaponeurotic complex of the foot of laboratory animals (control group: animals with the introduction of physiological sodium chloride solution (n = 12); main group: animals with the introduction of alprostadil (n = 12)). The methods of light microscopy (staining with alcian and toluidine blue, according to Van Gieson, Weigert – Van Gieson and Picro-Mallory) and morphometry were used.Results and discussion. As a result of the study, it was found that the four-fold administration of alprostadil had a significant effect on the structure of the dense fibrous connective tissue of the plantar foot of laboratory animals. The mechanisms of damage (edema, microhemorrhages, infiltration by lymphocytes, plasmocytes and leukocytes, dystrophy by the type of mucoid and fibrinoid swelling, delamination and rupture of collagen fibers), adaptation and regeneration (the appearance of a large number of activated fibrocytes, fibroblasts, microvessels, neoplasm of collagen fibers) were activated. All this together led to spatial focal histotopographic changes, consisting in an increase in the cellular composition of connective tissue structures against the background of a noticeable violation of their spatial orientation.Conclusion. Modeling of fasciopathy using alprostadil was accompanied by the appearance of mosaic reversible and irreversible heteromorphic and heterochronous changes in all connective tissue aponeurotic structures. Such histotopographic changes should be considered as one of the reasons for the clinical manifestations of plantar fasciopathies, causing functional insufficiency and explaining the clinical recurrent nature of the pathological process

SeaSoar CTD observations from the central Oregon shelf, cruise W9907C : 13-31 July 1999 : a component of the Prediction of Wind-Driven Coastal Circulation Project

The primary objectives of R/V Wecoma cruise W9907C were to: 1) collect threedimensional fields of temperature, salinity, and light absorption and attenuation using the towed, undulating vehicle SeaSoar; 2) collect 3-D fields of velocity using shipboard ADCP; 3) to make turbulence profiles along a single cross-shelf transect; and 4) locate, recover, and either redeploy or replace a NOPP mooring which had been damaged by a fishing trawler earlier in the season