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71.
The concept of a steady state tokamak with plasma facing components (PFC) on the basis of liquid lithium circulation demands the decision of three tasks: lithium injection to the plasma, lithium ions collection before their deposition on the vacuum vessel and lithium returning to the injection zone. Main subject of paper is the investigations of Li collection by different types of limiters intersected the scrape-of-layer (SOL) in T-10 and T-11M tokamaks. For finding solution for this problem in T-11M and T-10, experiments have been applied with Li-, C-rail limiters and ring SS R-limiter-collector (T-11M). The efficiency of Li collection by limiters in T-11M and T-10 tokamaks was investigated by post mortem sample–witness analysis and (T-11M) by the use of the mobile graphite probe (limiter) as a recombination target in the stream of lithium ions. The characteristic depth of lithium penetration in the SOL area of T-11M is about 2 cm and 4 cm in SOL of T-10. The quantitative analysis of the sample–witnesses located on T-11M limiters showed that 60 ± 20% of the lithium injected during plasma operating of T-11M had been collected by limiters. It confirms an opportunity of the lithium ions collection by limiters in tokamak SOL.  相似文献   
72.
Monometallic cobalt and bimetallic Co–Pt samples of various particle sizes have been prepared using SiO2 and synthetic kenyaite (layered silicate) as a support. They are characterized by elemental analysis, XRD, TPR, and XPS. Cobalt is introduced by two methods—classical impregnation and ammonia method. The ammonia method of preparation leads to the formation of finely dispersed Co3O4 on both supports. Besides, hardly reducible cobalt silicate phases appear predominantly on the SiO2 support. The Co3O4 particle size varies between 5 and 20 nm, depending on the support. The monometallic Co samples prepared by ammonia method on both supports are more active in benzene combustion than the impregnated ones due to the finer dispersion of the easily reducible Co3O4. Addition of Pt improves the activity and the promoting effect is more evident for the impregnated sample. This is explained with the synergy effect of cobalt oxide species and Pt. The less promoting effect of Pt on the catalytic activity of the bimetallic kenyaite-supported samples is attributed to the stronger interaction between the Co oxide phase and Pt during the preparation process.  相似文献   
73.
Improving the quality of equipment training for the Heavy Equipment Operators (HEO) is a critical task in improving safety and eliminating equipment-related injuries in mining. One of major responsibilities for the HEOs is proper machine inspection. Traditional miner safety training includes the use of hardcopy documents and video instructions. However, modern mobile and computer technology offers tremendous potential to improve the training process. In this study, we apply a 360-degree camera, open-source platform WordPress™, and the software Unity3D in order to create materials and tools for the HEOs safety training to help trainees better understand the pre-shift safety machine inspection. The computer-based safety task training developed in this research is tested and implemented at a surface mine in the southern United States.  相似文献   
74.
Stress-induced conditions are associated with impaired cerebral blood flow (CBF) and increased risk of dementia and stroke. However, these conditions do not develop in resilient humans and animals. Here the effects of predator stress (PS, cat urine scent, ten days) on CBF and mechanisms of CBF regulation were compared in PS-susceptible (PSs) and PS-resilient (PSr) rats. Fourteen days post-stress, the rats were segregated into PSs and PSr groups based on a behavior-related anxiety index (AI). CBF and its endothelium-dependent changes were measured in the parietal cortex by laser Doppler flowmetry. The major findings are: (1) PS susceptibility was associated with reduced basal CBF and endothelial dysfunction. In PSr rats, the basal CBF was higher, and endothelial dysfunction was attenuated. (2) CBF was inversely correlated with the AI of PS-exposed rats. (3) Endothelial dysfunction was associated with a decrease in eNOS mRNA in PSs rats compared to the PSr and control rats. (4) Brain dopamine was reduced in PSs rats and increased in PSr rats. (5) Plasma corticosterone of PSs was reduced compared to PSr and control rats. (6) A hypercoagulation state was present in PSs rats but not in PSr rats. Thus, potential stress resilience mechanisms that are protective for CBF were identified.  相似文献   
75.
76.
Changes in bacterial physiology caused by the combined action of the magnetic force and microgravity were studied in Escherichia coli grown using a specially developed device aboard the International Space Station. The morphology and metabolism of E. coli grown under spaceflight (SF) or combined spaceflight and magnetic force (SF + MF) conditions were compared with ground cultivated bacteria grown under standard (control) or magnetic force (MF) conditions. SF, SF + MF, and MF conditions provided the up-regulation of Ag43 auto-transporter and cell auto-aggregation. The magnetic force caused visible clustering of non-sedimenting bacteria that formed matrix-containing aggregates under SF + MF and MF conditions. Cell auto-aggregation was accompanied by up-regulation of glyoxylate shunt enzymes and Vitamin B12 transporter BtuB. Under SF and SF + MF but not MF conditions nutrition and oxygen limitations were manifested by the down-regulation of glycolysis and TCA enzymes and the up-regulation of methylglyoxal bypass. Bacteria grown under combined SF + MF conditions demonstrated superior up-regulation of enzymes of the methylglyoxal bypass and down-regulation of glycolysis and TCA enzymes compared to SF conditions, suggesting that the magnetic force strengthened the effects of microgravity on the bacterial metabolism. This strengthening appeared to be due to magnetic force-dependent bacterial clustering within a small volume that reinforced the effects of the microgravity-driven absence of convectional flows.  相似文献   
77.
Producing syngas and hydrogen from biofuels is a promising technology in the modern energy. In this work results of authors’ research aimed at design of supported membranes for oxygen and hydrogen separation are reviewed. Nanocomposites were deposited as thin layers on Ni–Al foam substrates. Oxygen separation membranes were tested in CH4 selective oxidation/oxi-dry reforming. The hydrogen separation membranes were tested in C2H5OH steam reforming. High oxygen/hydrogen fluxes were demonstrated. For oxygen separation membranes syngas yield and methane conversion increase with temperature and contact time. For reactor with hydrogen separation membrane a good performance in ethanol steam reforming was obtained. Hydrogen permeation increases with ethanol inlet concentration, then a slight decrease is observed. The results of tests demonstrated the oxygen/hydrogen permeability promising for the practical application, high catalytic performance and a good thermochemical stability.  相似文献   
78.
Starches isolated at different stages of maturation (milky, waxy, complete maturation) of wrinkled peas were investigated by differential scanning calorimetry (DSC) and X‐ray diffraction (XRD). It was shown that the maturation of wrinkled peas is accompanied by changes in the structural and thermodynamic properties of starches. The melting process of milky starches could be approximated by means of a “two‐state” model. The melting process of the waxy and completely maturated starches was described as the melting of a mixture of low and high temperature populations of double‐helical type crystallites, denoted as B‐ and B*‐types, as well as the melting of Vh ‐type crystallites. The relative amounts of the three structures were determined by deconvolution of the calorimetric peaks. The values of the melting cooperative units ( ϑ ) and the thickness of the crystalline lamellae (pitch heights) for starches were determined using mathematical models describing the melting processes. The values of the ϑ for milky, waxy, and completely maturated starches were calculated as 18 and 29 anhydroglucose residues, respectively. The thickness of the crystalline lamellae of B‐type crystals in the milky, waxy, and completely maturated starches were calculated. Structural changes in starch granules during maturation of wrinkled pea are discussed.  相似文献   
79.
The Journal of Supercomputing - In the paper, the problem of efficient parallel execution of numerical algorithms for supercomputers in the LuNA system is concerned. With LuNA, an application...  相似文献   
80.
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