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Formalism is developed for description of microstructure transformations and phase separation in systems under irradiation. Investigation is made within the scope of the crystal phase-field method. This approach allows one to simulate materials on the molecular-dynamics spatial scales but on the diffusive-dynamics temporal scales. Considering a model for a periodic one-component system driven by both competing stochastic fluxes–thermally-stimulated and external ballistic mixing flues of atoms, conditions of microstructure-transformations’ appearance are determined. Analysis of the system on a mesoscopic level for a binary equiatomic system is performed. Reentrant character of phase-separation process is revealed. For systems with transient dynamics, for instance, with incommensurable time scales of propagation of disturbances, which are characterized by the memory effects, at presence of fluctuations of lengths of jumps of the atoms knocked-on by high-energy particles, occurrence of pattern-selection processes is revealed.

The paper presents the results of studying the influence of long-term soaking on the structure and properties of samples made by selective laser melting of Inconel 625 alloy powders, produced by the method of off-center plasma spraying of a rapidly rotating rod billet (PREP-process). Investigations of chemical composition, macro- and microstructure, mechanical and heat-resistant properties of the samples plotted in xy and z direction was performed. Samples after building and hot isostatic pressing with subsequent heat treatment by different variants were to be examined. Investigation results showed that performance of the operation of hot isostatic pressing of the samples with subsequent standard heat treatment promotes practically complete elimination of microporosity in inner volumes of the metal and obtaining a more uniform solid solution. It was established that long-term soaking at the temperature of 900 °C, facilitates lowering of ductile and heat-resistant properties of Inconel 625 alloy due to lamellar precipitates of d-phase. Performed study was the basis for recommending the recovery heat treatment mode. In addition, it is shown that long-term soaking at the temperatures of 700 and 980 °? does not lead to precipitation of lamellar d-phase. [ABSTRACT FROM AUTHOR]

In this paper, we synthesize active carbon samples with various content of nitrogen and oxygen of heteroatoms, as well as surface functional groups. We determine the specific surface area and porosity of the obtained carbon, study its behaviour in the model oxide reduction processes, notably electrochemical oxygen reduction and catalytic decomposition of hydrogen peroxide. Relying on the data analysis, we characterize the impact of surface chemistry and porosity on the electron-donating ability of nitrogen and oxygen containing active carbons. We take the perspective that this carbon can be applied as a fuel cell electrocatalyst. [ABSTRACT FROM AUTHOR]

The authors studied the influence of lozartan -angiotensin II antagonist on the state of cardiohemodynamics and function of vessel endothelial cell in patients with CODL in the process of the treatment. 90 patients with stage II or III CODL in remission (average age is 50.46+/-5.1) have been observed. The average duration of the disease was 16.2+/-7.6 years. 30 patients received additionally lozartan -angiotensin II antagonist. Cardiohemodynamics has been assessed using Doppler ultrasonography. To assess the state of function of vessel endothelial cell the authors carried out reactive hyperemia test and calculated the level of nitrite nitrogen in blood plasma and erythrocytes. The duration of observation was 12 weeks. Losartan appeared to be effective in patients with CODL to correct compromised cardiohemodynamics. Losartan dicreases the disfunction of endothelial cell and has cardioprotective properties.

A clinicomorphological analysis was performed of the gastric antrum mucous membrane of 60 patients after selective proximal vagotomy because of stenosing duodenal ulcer. The patients were subdivided into two randomized groups depending on the type of the draining operation. The first group had a gastroduodenoanastomosis for the gastric drainage and the second group underwent duodenum plasty (drainage of the duodenum). Discontinuation of the pylorus function in the gastric drainage operation resulted in higher incidence and intensity of duodenum-gastric reflux and made more severe antrum gastritis; reflux-gastritis developed frequently. Morphological signs of reflux-gastritis in 95% of cases coincided with the results of the radionuclide method. Duodeno-gastric reflux decreased as a rule Helicobacter pylori (HP) contamination of the mucous membrane but did not eliminate it completely in all cases. The combination of these two factors resulted in more severe gastritis than that provoked by each of them separately. The etiology of gastritis and its intensity may be determined only by morphological examination of gastric mucous membrane. The results of endoscopic and histologic methods coincided in 70% of cases. Duodenal-gastric reflux, HP and high acid production play a certain role in ulcer recurrence.

Experience in the treatment of 70 patients with stenotic duodenal ulcer by surgery is generalized. In addition to SPV the patients underwent duodenoplasty as a draining operation. There were 61 (87.1%) males and 9 (12.9%) females. Their ages ranged from 18 to 70 years. The stenosis was compensated in 21 (30%), ++non-compensated in 32 (45.7%), and decompensated in 17 (24.3%) patients. To determine the possibility of performing SPV, the maintenance of the gastric contractile activity was studied by noninvasive methods: computed peripheral electrogastrography and computed gastro-scintigraphy. Involvement of the pylorus into the cicatricial-ulcerous inflammatory infiltration is the main contraindication for duodenoplasty. In view of that, intensive 2-3 week preoperative antiulcer therapy acquires particular significance; it removes or reduces significantly the inflammatory infiltration in most cases and raises the possibility of conducting duodenoplasty. Only intraoperative inspection of the pyloroduodenal segment allows the possibility and type of pylorus -preserving duodenum draining operation to be determined. This operation can be undertaken if the proximal boundary of the stenotic cicatricial-ulcerous deformity is at a distance of at least 1 cm from the pyloric sphincter, whatever the degree and length of the narrowing. A total of 43 operations form the Heineke-Mikulicz Mikulicz duodenoplasty, 17 for Finney's pyloroplasty, and 10 for bulbo-duodenostomy were carried out. The authors consider excision of the duodenal ulcer to be expedient and safe only when it is located on the anterior wall; it was carried out in 9 cases.(ABSTRACT TRUNCATED AT 250 WORDS)