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Copyright of Chinese Journal of Applied Mechanics is the property of Chinese Journal of Applied Mechanics Editorial Office 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.)

Austenitic stainless steels are used as important structural materials in nuclear reactors due to their high fracture toughness. In the process of long-term service, austenitic stainless steel will be subjected to neutron irradiation to cause microstructural changes, such as the formation of dislocation loop and precipitation, which will lead to a decrease in fracture toughness and affect its service behavior. The irradiation embrittlement behavior of austenitic stainless steels, i.e., the reducing of fracture toughness, should be considered in the life extension of the nuclear reactor. According to the relationship between fracture toughness and tensile properties, the prediction of fracture toughness after irradiation can be realized by using the tensile test data after irradiation. In order to predict the irradiation embrittlement bahavior of austenitic stainless steels, firstly, according to the correlation relationship between irradiation hardening and irradiated microstructure information, the post-irradiation microstructure information was used to predict the tensile yield stress after irradiation. Then, according to the correlation relationship of irradiation hardening and fracture toughness, the uniform elongation, yield stress/flow stress and fracture toughness before irradiation, combined with the yield stress/flow stress and uniform elongation obtained after irradiation, the prediction of fracture toughness of austenitic stainless steel after irradiation was realized, that is, the prediction of irradiation embrittlement of austenitic stainless steel was realized. Through the above steps, the fracture toughness of austenitic stainless steel can be directly predicted based on the microstructure information after irradiation. By using the microstructure information from experimental data obtained in the literature, the predicted fracture toughness was basically consistent with the experimental value of fracture toughness of austenitic stainless steel reported in the literature, which verified the effectiveness of the model. The results show that the dislocation loop formed after irradiation are the main microstructures that cause the irradiation embrittlement of austenitic stainless steels. In the future, the irradiation embrittlement of austenitic stainless steel can be predicted based on the microstructure information obtained by experimental test or simulation calculation, which provides a theoretical guidance for reactor life extension.

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology 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.)

Wet flue gas desulfurization (WFGD) device is a key piece of equipment used to control selenium, but its removal efficiency is highly variable (13%–95%). Adding internal components into WFGD can alter the gas-liquid flow pattern and is regarded as a promising technology for selenium removal. In this study, the demister and wall ring were adopted as internal components to investigate their feasibility on selenium removal and inherent mechanisms. Compared with the open tower (without internal components), the outlet selenium concentration was reduced by 52.2%–61.7% by installing a demister. This was because a liquid film was formed on the baffle plates of the demister after intercepting mists, which leaded a secondary absorption process for selenium. The lower plates of the demister made a major contribution to selenium removal, and increasing the plate area of the demister was beneficial to this process. The wall ring reduced the selenium emission by up to 56.5%, because it could force the flue gas and liquid column near/on the walls to flow towards the center, and significantly improve the gas-liquid contact. The enhanced method and mechanisms reported in this study can help to develop a low-cost technology to improve the selenium purification efficiency of existing WFGDs. [Display omitted] • The internal component technology was developed for selenium removal. • Both demister and wall ring enhanced the selenium absorption process in WFGD. • Liquid film on demister caused a secondary absorption process for selenium. • The lower surfaces of demister made a major contribution for selenium removal. • The wall ring forced the flue gas and liquid column to flow towards the center. [ABSTRACT FROM AUTHOR]

In this work, copper (Cu) was recovered from the discarded printed circuit board (PCB) of personal computer through foam fractionation. The discarded PCB was treated by acid leaching. The leaching yield of Cu ion reached 97.61% under the conditions of temperature 40ºC, nitric acid concentration 6 mol/L and leaching time 60 min. A novel foam fractionation column was developed to strengthen foam drainage. Under the suitable conditions of pH 4.0, volumetric airflow rate 70 mL/min, SDS concentration 0.12 g/L and loading liquid volume 500 mL, enrichment ratio and recovery percentage of Cu ion were 29.1% and 90.2%, respectively. [ABSTRACT FROM AUTHOR]

Abstract Many models describing the Earth’s magnetic field exist and are maintained by international research organizations. However, no clear general overview of the cross-compared quality of these models is available. An evaluation of the internal component and of the anomaly field as estimated by a selection of nine geomagnetic models with global coverage is presented here. Anomaly field models are also compared with an external, independently processed marine dataset extracted from Shom’s (the French Hydrographic and Oceanographic Service) geophysical database. The comparative study shows that internal geomagnetic fields computed outside the provisional domain, up to degrees 12 or 13 of spherical harmonics (SH), can be considered as equivalent. Relative amplitude differences with the World Magnetic Model 2015 (WMM2015) and the 12th generation of the International Geomagnetic Reference Field (IGRF-12) taken as references are lower than 10 nT. For an extent reduced to the north-eastern Atlantic Ocean and western Mediterranean Sea, anomaly field models up to SH degree 720 and the 3rd version of the Earth Magnetic Anomaly Grid (EMAG2v3) at the equivalent 0.5° resolution are the closest models to the filtered marine data. However, they are significant spatial discrepancies and standard deviations of differences between models and data are about 65 nT. The 3-arc-minute World Digital Magnetic Anomaly Map (WDMAM) best reflects the unfiltered marine data, but with significant standard deviations of about 70 nT. Results demonstrate that any model can be used with insignificant errors to compute raw anomalies from total field measurements by removing the internal component of the Earth’s magnetic field. In addition, they suggest that the priority should be given to WDMAM for levelling and evaluating marine datasets and for computing enhanced high-resolution regional magnetic maps.

Copyright of Clean Coal Technology is the property of Clean Coal Technology 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.)

It is widely acknowledged that the value of a house is the mixture of a large number of characteristics. House price prediction thus presents a unique set of challenges in practice. While a large body of works are dedicated to this task, their performance and applications have been limited by the shortage of long time span of transaction data, the absence of real-world settings and the insufficiency of housing features. To this end, a time-aware latent hierarchical model is developed to capture underlying spatiotemporal interactions behind the evolution of house prices. The hierarchical perspective obviates the need for historical transaction data of exactly same houses when temporal effects are considered. The proposed framework is examined on a large-scale dataset of the property transaction in Beijing. The whole experimental procedure strictly conforms to the real-world scenario. The empirical evaluation results demonstrate the outperformance of our approach over alternative competitive methods. We also group housing features into both external and internal clusters. The further experiment unveils that external component shapes house prices much more heavily than the internal one does. More interestingly, the inference of latent neighborhood value in our model is empirically shown to be able to lessen the dependence on the critical external cluster of features in house price prediction. [ABSTRACT FROM AUTHOR]