Heat treatment forming a dissipative metal base in wear-resistant chromium-alloyed cast iron

The maximum abrasive wear resistance is provided by a metal base from metastable retained austenite and martensite. Such a microstructure of 260Kh16M2 and 250Kh25MFT chromium cast irons with different types of Cr 7 C 3 and Cr 23 C 6 , carbides is created by high-temperature quenching with heating to temperatures of 1125-1170 °C and cooling in oil or air. Austenite is transformed to disperse martensite on the working surface as a result of the impact of abrasive particles during operation. Together with carbides, it provides a high hardening level and a high working capacity of the secondary microstructure of the cast irons. © 2018 Author(s)

The experimental cascade curves of EAS at E sub 0 10(17) eV obtained by the method of detection of Cherenkov pulse shape

The individual cascade curves of EAS with E sub 0 10 to the 17th power eV/I to 3/ were studied by detection of EAS Cherenkov light pulses. The scintillators located at the center of the Yakutsk EAS array within a 500-m radius circle were used to select the showers and to determine the main EAS parameters. The individual cascade curves N(t) were obtained using the EAS Cherenkov light pulses satisfying the following requirements: (1) the signal-to-noise ratio fm/delta sub n 15, (2) the EAS axis-detector distance tau sub 350 m, (3) the zenith angle theta 30 deg, (4) the probability for EAS to be detected by scintillators W 0.8. Condition (1) arises from the desire to reduce the amplitude distortion of Cherenkov pulses due to noise and determines the range of EAS sizes, N(t). The resolution times of the Cherenkov pulse shape detectors are tau sub 0 approx. 23 ns which results in distortion of a pulse during the process of the detection. The distortion of pulses due to the finiteness of tau sub 0 value was estimated. It is shown that the rise time of pulse becomes greater as tau sub 0.5/tau sub 0 ratio decreases

About some educational trends: problems and prospects

The article views some western trends in the contemporary system of Russian education. The authors explain the essence of such educational approaches as tutoring and foresight and analyze basic problems and prospects of introducing these approaches into the system of professional educationРассматривается реализация западных тенденций в современной системе российского образования. Раскрывается сущность таких подходов, как тьюторство и форсайт, и анализируют основные трудности и перспективы их внедрения в систему российского профессионального образовани

ВЫБОР ЗЕМЕЛЬНЫХ УЧАСТКОВ ДЛЯ ТЕРМИНАЛЬНО-ЛОГИСТИЧЕСКИХ ОБЪЕКТОВ

The construction of terminal logistics centers constitutes one of the strategic goals of transport development. The choice of lots of land for those centers requires criteria that will be well adapted to market conditions, including dominant economic factors, related to property relations, cadastral price and other factors. The authors suggest the approaches of solution of such problems, including algorithms of comparative analysis of the variants of location of the transport logistics centers, assessment criteria series, weighted criteria values, the resulted effects.Строительство терминально-логистических центров (ТЛЦ) – одна из стратегических целей транспортного развития. Выбор земельных участков под такие объекты требует иметь адаптированные под рыночные условия критерии, включая основополагающие экономические доминанты, связанные с отношениями собственности, кадастровой стоимостью земли и другими факторами. Авторы предлагают подходы к решению подобных задач, в том числе алгоритмы сравнительного анализа вариантов размещения ТЛЦ, критериальный оценочный ряд, весовые значения критериев, их результирующие эффекты.

Neurophysiological features of the nociceptive trigeminal pathway in abdominally obese migraineurs

The aim of this study were to assess clinical (cutaneous allodynia) and neurophysiological (R2 nBR component) markers of the nociceptive trigeminal-cervical pathway sensitization in the abdominally obese patients with episodic (EM) and chronic migraine (CM). Materials and methods: It had been recorded nBR within interictal period in 79 migraineurs with EM and CM who had abdominal obesity (AO) and normal body weight (NBW). Results: Patients with EM and AO had significantly lower pain thresholds than patients with EM and NBW – 0,55 (0,34-0,63) μV vs 0,70 (0,59-1,03) μV. The mean latency of R2 nBR component was significantly decreased in patients who had EM and AO (36,59 (31,95-42,41) ms) compared to patients who had EM and NBW(46,75 (42,93-52,34) ms). It had been revealed significant increasing of the mean amplitude of the component R2 nBR in patients who had EM and AO (158 (115-197) μV) compared to patients who had EM and NBW (124 (76-144) μV). In patients who had CM and AO, it had been found direct positive correlation between the amplitude of R2 nBR and severity of cutaneous allodynia – τ=0,4 (p=0,03), as well as found negative correlation between the latency of R2 nBR and severity of cutaneous allodynia – τ=-0,44 (p=0,02) within the interictal period of migraine. Conclusions: Neurophysiological findings may indirectly indicate faster migraine chronification in patients with EM and AO

ОРГАНИЗАЦИЯ ЗАКУПОК ДЛЯ МЕЖДУНАРОДНЫХ ИНФРАСТРУКТУРНЫХ ПРОЕКТОВ

The authors study participation of state corporations and companies, who are natural monopolies, in the purchases of the goods and services during execution of international infrastructural projects, particularly the jurisdiction of the contracting parties, functions and forms of project activities, features of financing and investments, managerial aspects of accompanying business-processes. All these aspects undergo factorial and structural analysis at example of JSC Russian Railways taking into consideration federal laws and regulations.Участие государственных корпораций и компаний, субъектов естественных монополий в закупках товаров, работ и услуг в ходе реализации  международных инфраструктурных проектов. Юрисдикция сторон  договорных отношений, виды и функции проектной деятельности, особенности финансирования  и инвестирования, а также управленческие аспекты сопутствующих бизнес-процессов. Факторный и структурный анализ  на примере ОАО «РЖД» и с учетом действующих федеральных законодательных норм

Remobilization of leaf S compounds and senescence in response to restricted sulphate supply during the vegetative stage of oilseed rape are affected by mineral N availability

The impact of sulphur limitation on the remobilization of endogenous S compounds during the rosette stage of oilseed rape, and the interactions with N availability on these processes, were examined using a long-term 34SO42− labelling method combined with a study of leaf senescence progression (using SAG12/Cab as a molecular indicator) and gene expression of the transporters, BnSultr4;1 and BnSultr4;2, involved in vacuolar sulphate efflux. After 51 d on hydroponic culture at 0.3 mM 34SO42− (1 atom% excess), the labelling was stopped and plants were subject for 28 d to High S-High N (HS-HN, control), Low S-High N (LS-HN) or Low S-Low N (LS-LN) conditions. Compared with the control, LS-HN plants showed delayed leaf senescence and, whilst the shoot growth and the foliar soluble protein amounts were not affected, S, 34S, and SO42− amounts in the old leaves declined rapidly and were associated with the up-regulation of BnSultr4;1. In LS-LN plants, shoot growth was reduced, leaf senescence was accelerated, and the rapid S mobilization in old leaves was accompanied by decreased 34S and SO42−, higher protein mobilization, and up-regulation of BnSultr4;2, but without any change of expression of BnSultr4;1. The data suggest that to sustain the S demand for growth under S restriction (i) vacuolar SO42− is specifically remobilized in LS-HN conditions without any acceleration of leaf senescence, (ii) SO42− mobilization is related to an up-regulation of BnSultr4;1 and/or BnSultr4;2 expression, and (iii) the relationship between sulphate mobilization and up-regulation of expression of BnSultr4 genes is specifically dependent on the N availability

Potential of azoximere bromide for treatment of patients with acute inflammatory and infectious upper respiratory diseases

Aim. To evaluate the efficacy and safety of Polyoxidonium® in patients with inflammatory and infectious upper respiratory diseases in real clinical practice. Materials and methods. This retrospective multicenter study included data from adults and children over 6 months old with inflammatory and infectious upper respiratory diseases (n=16 365). The exploratory endpoints included: the proportion of patients with complete relief of symptoms, demographic characteristics of patients, the frequency of prescriptions of Polyoxidonium® by disease groups, determination of the groups of concomitant drugs, most commonly prescribed treatment regimen, frequency of prescribing different Polyoxidonium® dosage forms, duration of the most common specific symptoms of acute respiratory infections during therapy, the incidence of treatment-related adverse events. Results. After treatment completion, the proportion of patients with complete relief of symptoms was 40%, with positive dynamics – 99.77%. Polyoxidonium® in combination therapy was also effective in the treatment of COVID-19 and Post-COVID-19 syndrome. The median patient age was 28 years. Polyoxidonium® was most frequently prescribed for the treatment of inflammatory and infectious upper respiratory diseases in combination with antibiotics or symptomatic drugs in dosage form solution. The primary routes of administration were intranasal and sublingual. The resolution of infection symptoms occurred predominantly within the first 5 days after the initiation of therapy. The therapy appeared to be equally effective across all age groups. No Polyoxidonium®-related adverse events occurred. Conclusion. Treatment with Polyoxidonium® contributes to achieving favorable outcomes in patients with inflammatory and infectious upper respiratory diseases. The study drug has a high safety profile

Thermal properties and structure of cast carbon-containing invar and superinvar alloys after two-stage annealing

The effect of carbon content on thermal properties of cast superinvar alloys subjected to two-stage annealing is studied. It is shown that carbon improves the casting properties of the alloys but raises the temperature coefficient of linear expansion (CTLE). Two-stage high-temperature annealing makes it possible to remove carbon from the solid solution and to transfer it into graphite, which is accompanied by decrease in the CTLE. © 2013 Springer Science+Business Media New York