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The chemical vapor transport reactions (CVTRs) occurring in the intrachamber space of the T‑11M tokamak have been studied using elements of protective electrical-insulating ceramics based on electrotechnical porcelain (ETP). It is shown that the mechanisms of CVTR flow, their predominant products, and accumulation zones of the latter depend on the layout, namely, the presence or absence of steel foil shielding ceramic protection elements. It has been found that shielding of protective in-chamber ETP elements does not completely suppress CTRV, but leads to a change in its mechanism. Thus, ceramic protection made of ETP or corundum (Al2O3), even when equipped with steel shielding, does not exclude elements with high values of Z (Al and Si) from entering the plasma flow. If ETP is used, steel shielding can complicate the situation by causing additional emissions of iron, which forms a volatile silicide. The decisive importance of two factors in choosing the optimal metal oxide ceramics is shown: the location of the corresponding metal in the Beketov's metal displacement series and its fugacity. Calculations of the latter were carried out using modern software based on the Clausius–Clapeyron equation. Periclase (MgO) and lithium oxide (Li2O) ceramics are recommended as optimal for protective insulating in-chamber ETP elements. [ABSTRACT FROM AUTHOR]

Copyright of Larq Journal for Philosophy, Linguistics & Social Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Argentina grows the second‐largest area of lucerne in the world. Despite its importance, a yield gap exists between potential and measured yields, but factors contributing to it are still unclear. This study aimed to identify management factors and research needs to reduce the lucerne yield gap to improve the livestock systems in this region. We used meteorological data coupled with lucerne crop modelling and measured yields from the National Lucerne Cultivar Evaluation Network (NLCEN) to quantify the lucerne yield gap in nine sites located within the Argentinian Pampas (between parallels 30–45°S and meridians 58–65°W) and three sites outside the Pampas. Specifically, we used the model developed by McCall & Bishop‐Hurley (2003), adapted and calibrated for lucerne in Argentina by Berone et al. (2017) to estimate the potential yield (PY) for 12 locations (three irrigated and nine rainfed), and compared those results with measured yields from the NLCEN to calculate yield gaps. We found the average available photosynthetic active radiation (PAR) and temperatures were sufficient to achieve 21.5 ± 3.7 t dry matter (DM) ha−1 yr−1 under rainfed conditions (environments with mean annual rainfall from 400 to 1,200 mm). However, the average measured yield from the NLCEN was 16.8 ± 2.4 t DM ha−1 yr−1 (a 22% gap). Potential yields ranged between 10 and 25 t DM ha−1 yr−1 under rainfed conditions and between 25 and 39 t DM ha−1 yr−1 for irrigated crops. As latitude increased rainfed locations had lower yields, while irrigated locations had higher yields. Adding irrigation was predicted to increase yields to 35.4 ± 2.0 t DM ha−1 yr−1 (a 53% gap) in rainfed sites. For irrigated locations, the gap was smaller (27.3 ± 3.5 vs 32.4 ± 2.2 t DM ha−1 yr−1 for measured vs potential yield, respectively), and most likely linked to nutrient deficits. Also, current grazing management was estimated to achieve approximately 50% less grazing efficiency than optimal grazing management. Our results demonstrated that the livestock industry can potentially increase animal production under current environmental conditions. The four main adjustments to achieve this are increased use of irrigation, increased use of fertilisers, earlier commencement of grazing in spring and increased stocking rates. The costs of irrigation, fertilisers and grazing management are envisaged to be small compared with potential increases in incomes and thus profitability available to beef and dairy farmers using lucerne as a major feed source in Argentina. [ABSTRACT FROM AUTHOR]

Objective: To produce Serrano peppers using a new cultivation technique that mixes the best of hydroponic cultivation and traditional cultivation. Design/methodology/approach: We set up a growing system where the Serrano pepper grew from seedling to its full-fledged state, in a growbag containing sand (as support material), potassium polyacrylate (as water retention material), and a nutrient solution for vegetable gardens, under greenhouse conditions. The humidity level of the growbag is controlled by adding as much water with nutrient solution as needed. This technique has generated 100% harvestable plants (total: 20 plants); more than 90% of the water can be saved in comparison to regular and hydroponic cultivation. Results: Once the harvest began, at least 22.857 kg of Serrano pepper were obtained in 3 m² of soil in a system with a pyramidal structure in which the 20 plants were placed. If we extrapolated this data, approximately 93,000 kg of Serrano pepper could be harvested from a 1 ha system. Study Limitations/implications: This technique tries to tackle the water access limitations that may exist in some areas of Mexico. However, it does not mitigate the initial costs of a greenhouse system. Nevertheless, this technique can be reused up to 10 times without requiring maintenance. Findings/conclusions: Experience has shown that hydroponic crops are truly profitable, despite their vast water requirements, which is precisely what prevents their global expansion. However, our modification of this method saves more than 90% of the water, using potassium polyacrylate as a retention agent and sand as a support material. Therefore, this technique could be implemented even in places where water is scarce. [ABSTRACT FROM AUTHOR]

Copyright of Propósitos y Representaciones is the property of Universidad San Ignacio de Loyola and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A method is proposed to improve the service properties of the zinc coatings on steels formed by cold galvanizing in order to increase their reliability and durability. As a result of annealing a zinc coating in an ammonia medium, the formation of a hardened modified layer due to diffusion processes in both a steel substrate and a zinc coating is experimentally established. The structure of the hardened layer provides an increase in the wear resistance of the nitrided zinc coating and an increase in the adhesion of the coating to the substrate. The corrosion resistance of the nitrided zinc coatings in various media, namely, a saline solution, a weakly acidic medium, seawater, and salt fog, is shown to increase due to a combination of cathodic and barrier protection mechanisms. [ABSTRACT FROM AUTHOR]

We report a new nickel-iron alloy nanoparticle-decorated LaSrFe0.75Ni0.25O4 K2NiF4-type oxide with Ruddlesden-Popper structure (RP-LSFN), which performed as a high-performance sulfur-resistant anode prepared by using an infiltration method for solid oxide fuel cells (SOFCs) with LaSrFeNiO6-δ double perovskite (DP-LSFN) as the precursor. A reduction converts the DP-LSFN phase into mixed phases containing the RP-LSFN and FeNi3 nanoparticles. The morphology, thermal expansion behavior, sulfur tolerance, and electrochemical activity for hydrogen oxidation of this FeNi3 nanoparticle-decorated, RP-LSFN-infiltrated anode are investigated. An electrolyte-supported SOFC with this infiltrated anode generates a high power output of 541 mW cm−2 at 800 °C operated with 1000 ppm H2S−H2 as the fuel, which compares favorably to that with pure H2 fuel. A single cell with this anode demonstrates favorable stability at 800 °C during 90, 40, and 20 h operation with H2 containing 100, 200, and 1000 ppm H2S, respectively. [ABSTRACT FROM AUTHOR]

Various types of operational faults in critical machine parts are analyzed. The possibility of eliminating the factors responsible for such faults at the manufacturing stage is considered. Thermodynamic analysis reveals the relation between the bulk wear rate and the surface quality. [ABSTRACT FROM AUTHOR]

Ba0.5Sr0.5Co0.7In0.1Fe0.2O3− δ powders are successfully synthesized as the cathode materials for proton-conducting solid oxide fuel cells (SOFCs). The prepared cells consisting of the structure of a BaZr0.1Ce0.7Y0.2O3− δ (BZCY7)-NiO anode substrate, a BZCY7 electrolyte membrane and a cathode layer, are measured from 600 to 700 °C with humidified hydrogen (ca. 3% H2O) as the fuel. The electrochemical results show that the cell exhibits a high power density which could obtain an open-circuit potential of 0.986 V and a maximum power density of 400.84 mW cm−2 at 700 °C. The polarization resistance measured at the open-circuit condition is only 0.15 Ω cm2 at 700 °C. [ABSTRACT FROM AUTHOR]

A solid oxide fuel cell (SOFC) was developed for the direct utilization of dry glycerol to produce electricity at 800 °C. A state‐of‐art SOFC anode was covered by a thin (<10 μm) electrocatalyst layer based on a Ni‐modified perovskite and ceria. This electrocatalyst layer worked as an internal integrated fuel processor to convert glycerol in syngas. A performance of about 850 mW cm−2 @ 0.6 V was achieved with dry glycerol. A life time test of 160 hrs showed no relevant occurrence of carbon deposits. The developed approach can provide a practical route to achieve effective fuel flexibility in SOFCs. The promoting effect of an integrated catalytic fuel processor for the oxidation of dry glycerol. [ABSTRACT FROM AUTHOR]

Contact between a steel surface and a mixed solution of poly(N-vinylpyrrolidone) and copper sulfate leads to the reduction of copper(2+) ions and the formation of a nanocomposite consisting of copper nanoparticles and the polymer. Ultrasonic treatment of the reaction mixture yields a sol of the nanocomposite, the particles of which contain metal nanoparticles and their aggregates with sizes of 10-100 nm shielded by the polymer. The nanocomposite has been used as a precursor of a catalyst for steel nitriding, i.e., copper oxide, which is formed at high temperature via degradation of the nanocomposite and oxidation of copper nanoparticles. Owing to the small particle sizes, this catalyst is substantially more active than an analogous catalyst obtained by reducing copper ions in the absence of the polymer. [ABSTRACT FROM AUTHOR]

On contact of an aqueous solution containing poly- N-vinylpyrrolidone and copper sulfate with a steel surface, copper(II)ions are reduced on the steel surface to give nanocomposites comprising copper nanoparticles and the polymer. Ultrasonication of the reaction system results in the nanocomposite sol. Copper oxide nanoparticles formed upon decomposition of the nanocomposite and oxidation of copper nanoparticles at high temperature are active catalysts of steel nitriding. [ABSTRACT FROM AUTHOR]

Ti, Zr and Hf doped CeO films with (00 l) preferred orientation have been prepared on Ni-W substrates by chemical solution deposition method. The influence of ionic radii of dopants on the epitaxial growth process and oxygen diffusion behavior of CeMO (M = Ti, Zr, Hf) films were explored by X-ray diffraction and atomic force microscopy. Since the ionic radii of doping cations of Ti, Zr and Hf are smaller than that of Ce and the lattice parameter of Ni-W substrate is smaller than that of CeO film, the compressive strain exists primarily in the doped film. The doping cation with small radius leads to the small lattice parameter of CeO film and small lattice mismatch between Ni-W substrate and epitaxial film. The compressive strain decreases resulting from the elastically lattice deformation in the films, while the compressive strain leads to the increase of the growth rate for CeO grains. The results show that the doping cation with smaller ionic radius has important influence on the surface roughness and the out-of-plane texture. Moreover, binding energy of dopants and oxygen vacancies, oxygen migration energies and vacancy formation energies are related to the intrinsic oxygen diffusion coefficient of buffer layers. Ionic radius has significant effect on the migration energies of oxygen ions. The Ti doped film shows severe oxygen diffusion due to steric effects. Therefore, the selection of suitable dopants would benefit the improvement of texture and surface morphology as well as the ability against oxygen diffusion of buffer layer. [ABSTRACT FROM AUTHOR]

BaCe0.8Pr0.2O3 (BCP20) and BaCe0.6Pr0.4O3 (BCP40) powders are successfully synthesized through the Pechini method and used as the cathode materials for proton-conducting solid state oxide fuel cells (SOFCs). The prepared cells consisting of the structure of a BaZr0.1Ce0.7Y0.2O3-δ (BZCY7)-NiO anode substrate, a BZCY7 anode functional layer, a BZCY7 electrolyte membrane, and a cathode layer, are measured from 600 to 700 °C with humidified hydrogen (∼3% H2O) as the fuel and static air as the oxidant. The electricity results show that the cell with BCP40 cathode has a higher power density, which could obtain an open-circuit potential of 0.99 V and a maximum power density of 378 mW cm-2 at 700 °C. The polarization resistance measured at the open-circuit condition of BCP40 is only 0.16 Ω cm2 at 700 °C, which was less than BCP20. [ABSTRACT FROM AUTHOR]

Nanosized powders with a composition of (1- x)CeSmO- xBaceSmO ( x = 0, 0.3, and 1) were obtained by self-ignition combustion synthesis (SICS) from the appropriate nitrates and various organic fuels (glycine, glycerol, citric acid, and a mixture of citric acid and ethylene glycol). The most finely dispersed powders formed when the concentration of the perovskite phase in the system decreased or when glycerol or citric acid-enthyleneglycol mixture was used as a fuel during SICS. A procedure for the preparation of powders and nanostructured ceramics was developed and their electric properties were studied. [ABSTRACT FROM AUTHOR]

The effect of anode off-gas recycling (AOGR) on the characteristic performance of a natural gas reformer equipped with a precious metal catalyst is investigated experimentally. The reformer is operated both with synthetic AOGR gas and in steam reforming (SR) conditions. The characteristic performance in SR and AOGR mode are compared with equilibrium, and it is found that equilibrium is more readily achieved in AOGR mode. The reformer is used for extended periods of time (100-1,000 h) in conditions where carbon formation is thermodynamically possible to measure any changes in characteristic performance. No significant change in the performance is observed due to carbon formation or catalyst deactivation. The reformer could be successfully implemented in a 10 kW SOFC system with an anode off-gas recycling loop. [ABSTRACT FROM AUTHOR]