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671.
Ettringite-accelerated binders composed of CAC–PC–C$ (calcium aluminate cement–Portland cement–calcium sulfate) and CSA–PC–C$ (calcium sulfoaluminate cement–Portland cement–calcium sulfate) have been used widely for indoor applications, such as self-leveling floor screeds, underlayment, and tile adhesives owing to their rapid setting, early strength gain, and shrinkage compensation properties. These properties also make these binders appealing candidates for outdoor rapid repair (e.g., highways, bridge decks, and airfield pavements). However, a central question remains: Does ettringite remain stable in outdoor exposure conditions? If so, which factors will contribute positively/negatively to the long-term stability of ettringite in these systems? To address these questions, this critical review presents the current state of knowledge regarding the hydration of ternary binders composed of CAC–PC–C$ and CSA–PC–C$ with respect to ettringite formation and the factors affecting the stability of ettringite thereafter. The purpose of this review paper is to synthesize and analyze current research regarding conditions that promote or deter ettringite stability, establish what information is missing, unclear, or contradictory, and identify remaining research needs to address the identified knowledge gaps.  相似文献   
672.
Residual native starch was extracted from sago pith residue using two types of commercial cell‐wall degrading enzymes, Pectinex Ultra SP‐L and Ultrazyme 100G. The first increased starch yield with a shorter incubation period than the second. The superior effect of Pectinex Ultra SP‐L was observed already at 0.5 h, where a wide granule size distribution (8—87 μm) was obtained. A slight increase in the release of granules ranging from 30—60 μm was noted within a 2 h incubation period. However, upon further incubation, the distribution pattern was similar to that of untreated samples. Samples treated with Ultrazyme 100G exhibited a unimodal distribution pattern, with larger granules, ranging from 40—70 μm, being released upon further incubation within a 2 h incubation period. However, all samples exhibited a bimodal distribution upon further incubation.  相似文献   
673.
Food Science and Biotechnology - Strawberry (Fragaria ananassa) is rich in bioactive compounds with high antioxidant activity. High pressure processing (HPP) is an efficient alternative to preserve...  相似文献   
674.
Transparent wood (TW)-based materials have increasingly become the focus of researchers worldwide owing to their superior physico-chemical-optical properties, sustainable nature, as well as the fact that they are highly accommodating frameworks that can act as building blocks to readily explore a vast range of potential functionalities, holding great potential to displace glass and plastics in their various respective applications. The integration of multiple functionalities into TW has been undertaken to fulfill the demands of prospective sophisticated applications through the utilization of functional fillers or coatings. Herein, the up-to-date foundational developments and reports concerning emergent TW composites and coatings from a perspective of fabrication-functionality-application are comprehensively summarized, with a particular focus on seven specific functionalities; i) solar control; ii) chromically-responsive, iii) electrically-conductive, iv) shape-memory active; v) flame-retardant; vi) electromagnetic interference shielding; and vii) aesthetics. The potential applications of TW with these functionalities are also discussed. Finally, the current challenge with TW is addressed, as well as the future developments required for eventual real-world application.  相似文献   
675.
This study covers a simulation on conjugate free convective in a porous enclosure containing a side wall thickness and partially heated and cooled from sides under the considerations of local thermal nonequilibrium (LTNE) and non-Darcy flow. Interest has been focused on how the side wall thickness and the locations of cooled and heated parts affect the effectiveness of the Nusselt number (Nu). Three different cases of localized heating and cooling locations have been implemented for the following ranges: scaled heat transfer coefficient ( 0.1 H 100 $0.1\le H\le 100$ ), wall to fluid thermal conductivity ratio ( 0.1 R k 100 $0.1{\le R}_{k}\le 100$ ), modified Rayleigh number ( 200 Ra * 1000 $200\le {Ra}* \le 1000$ ), wall width ( 0.1 Z ˆ 0.5 $0.1\le \hat{Z}\le 0.5$ ), inertial parameter ( 10 4 F s / P r * 10 2 ${10}^{-4}{\le F}_{s}/{P}_{r}^{* }\le {10}^{-2}$ ), and thermal conductivity ratio ( 0.1 K r 100 $0.1\le {K}_{r}\le 100$ ). Outcomes show that Z ˆ $\hat{Z}$ and the locations of cooled and heated parts have remarkable impacts on all the Nusselt numbers. The intensity of LTNE region considerably relies on Ra * ${Ra}{* }$ , K r ${K}_{r}$ and H $H$ . The total average NuT is highly dependent on R k ${R}_{k}$ , Ra * ${Ra}{* }$ , Z ˆ $\hat{Z}$ , F s / P r * ${F}_{s}/{P}_{r}^{* }$ , and K r ${K}_{r}$ as compared to H. The increase in Z ˆ $\hat{Z}$ leads to change of the convective mechanism to conductive mode. The rise in R k ${R}_{k}$ guides to increase Nu, where R k ${R}_{k}$ can control the flow strength. The actions of F s / P r * ${F}_{s}/{P}_{r}^{* }$ on Nuf is more evident than Nus. For low H and Kr, the size of LTNE zone is considerably affected by H as compared to Kr although Kr has a high influence on Nu. For high Kr and H, the LTNE zone has closely vanished. Findings display that the Case 2 provided the highest Nu for all tested parameters except the case of K r = 0.1 ${K}_{r}=0.1$ . Finally, it is evident that for the problems that employed solid conduction wall with localized heating and cooling sections, Case 2 is recommended for future use in the applications that implement a porous medium and depend on free convection.  相似文献   
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