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Self-regulation and language learning motivation have always been the research focus of foreign language acquisition. In higher education, the heterogeneity of college students creates diversity in SRL abilities, especially with the prevalence of online learning nowadays. The current study investigates the profiles of college EFL learners' self-regulation and predictive role of self-determination motivation on the membership of SRL profiles in an online learning environment. Online self-regulation learning questionnaire was administered to examine the potential profiles, and self-determination motivation questionnaire to reveal the relationship between online self-regulation and self-determination motivation with a total of 439 college EFL learners. Latent profile analysis yielded three subgroups of online self-regulation: high, median, and low. Multiple logistic regression analysis showed that external regulation, intrinsic motivation-stimulation, and intrinsic motivation-accomplishment in self-determination motivation can effectively predict the online self-regulation profiles membership. These results altogether suggest that online SRL profiles can be predicted by several aspects in self-determination motivation in EFL learning.

With the development of energy‐harvesting fabrics, woven structured textile‐based triboelectric nanogenerators (T‐TENGs) are widely proposed. However, most T‐TENGs with woven structures consist of one material, which greatly limits the functionality of T‐TENGs. This work focuses on structural design and rational material configuration to realize versatility of woven‐structured T‐TENG by a green, eco‐friendly, scalable production method. A 3D triboelectric nanogenerator fabric (3D SP‐FTENG) is proposed, which performs excellent electrical output (27.33 V, 1.76 µA, and 61.6 mW m−2) and wearability (directional water transport and breathability) as well as antibacterial activity. Moreover, in contrast to the previously reported multilayer T‐TENGs which are constructed by directly stacking multilayer functional fabrics together, the fabric interface of this new structure fabricated by weaving the support area and the functional area together is not easily delaminated. The 3D SP‐FTENG demonstrates outstanding durability (machine washability and ultrahigh abrasion resistance). In addition, the SP‐FTENG is able to drive wearable electronics and be used as a self‐powered sensor, such as constantly monitoring the movement signals of human body. This study presents a novel and sustainable strategy for the development of eco‐friendly multifunctional T‐TENGs. [ABSTRACT FROM AUTHOR]

A mathematical model is proposed to calculate the total separation effectiveness in terms of GT for a disk stack centrifuge taking account of the variation of the centrifugal force with a position in the disk. In practice, the centrifuge ability/force is often referred as Relative Centrifugal Force (RCF) or G number, which is a multiple of the centrifugal acceleration over the gravitational acceleration. As the radial velocity varies it is important to integrate the relative centrifuge force, here in terms of the G number along the path taking account of the change in velocity. The separation effectiveness, GT is defined as an integrated product of local G number, G(x) and local residential time (dt), where dt is the time taken for the bulk fluid to traverse a distance from r to r+ dr. The GT value calculated for a disk type centrifuge can be compared with the GT value of others and compared with a bench top fixed rotor centrifuge. An industrial centrifuge would be expected to be able to deliver similar separation performance to a pilot or a lab scale one, if operated at the same/similar value of GT. This would allow the performance of a full-scale clarifier to be predicted. This model is, in essence, a simple alternative to the Sigma concept. [ABSTRACT FROM AUTHOR]

The aim of this paper is to demonstrate that a simple stirred batch cell can be used to study the effects of surface shear stress (among other process parameters) on fouling from saturated calcium salt solutions. For otherwise identical operating conditions, the overall fouling rate on a smooth mild steel surface was found to be reduced either when fine wires were attached to it or when helical threads were incorporated into the surface, either in the form of a continuous helical groove or in the form of a raised helix. The raised helical surface was more effective in reducing fouling than the helical groove. The results confirm the general effect that fouling rates can be reduced by increasing the surface shear stress through surface enhancement. A simple mathematical model has been developed to take into account the dynamic change in bulk concentration as crystallization fouling occurs. In all cases, the overall fouling resistance increased asymptotically toward a constant value and could easily and accurately be described quantitatively by the new analytical model. The variations of shear stresses on the various surfaces were determined from computational fluid dynamics simulations using the commercial package Comsol 4.2. [ABSTRACT FROM PUBLISHER]