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The sintering pot test was used to investigate the effect of MgO/Al2O3 ratio in the range of 1.2 to 2.2 on the sintering behavior of iron ore. The main characterization methods of X-ray diffraction (XRD) and scanning electron microscopyenergy disperse spectroscopy (SEM-EDS) were employed. The results showed that the strength, yield, and reducibility of sinter initially increased and then decreased with increasing MgO/Al2O3 ratio from 1.2 to 2.2. The index would reach the peak value with the strength of 70.6% and the yield of 83.81%, respectively, when MgO/Al2O3 ratio was 1.8. The reduction index would reach the peak value of 88.54% with MgO/Al2O3 ratio of 1.6. The FeO content, solid fuel consumption, and the RDI+3.15 of sinter increased dramatically with increasing MgO/Al2O3 ratio. When MgO/Al2O3 ratio was up to 2.2, the solid fuel consumption and RDI+3.15 reached a maximum value of 61.93 kg/t and 96.1%, respectively. The form of SFCA was acicular when MgO/Al2O3 ratio was less than 1.6 and then transformed to plate-like which content also reduced. The magnetite increased while hematite decreased with enhancing MgO/Al2O3 ratio.

The effect of CaF2 substitution with TiO2 on the crystallization characteristics of low-fluoride slag was studied using differential scanning calorimetry (DSC) combined with XRD and SEM-EDS analysis. The effective activation energy for crystallization of the slag was evaluated. The results showed that the liquidus temperature of the slag increased unnoticeably with increasing TiO2 content. Increasing TiO2 addition from 4.3 wt% to 13.0 wt% decreased the undercooling of the slag and enhanced the crystallization ability of the slag. There is no change in the types and precipitation sequence of the crystalline phase in the slag with different TiO2 contents during continuous cooling. The crystalline phases were Ca12Al14O32F2, CaTiO3, MgO, and CaF2. The first and second crystallization phase were Ca12Al14O32F2 and CaTiO3, respectively. The dominant crystalline phase was faceted Ca12Al14O32F2 crystals. The morphology of CaTiO3 crystal changed from needle-like to blocky with increasing TiO2 content. The MgO crystal was with little blocky morphology, and the needlelike CaF2 distributed among CaTiO3 crystal. The precipitated amount of both MgO and CaF2 was very small. The effective activation energy for Ca12Al14O32F2 formation decreased with increasing TiO2 content in the slag, indicating that TiO2 enhanced the crystallization tendency of the slag.

A multiscale micromechanics-based progressive damage model is developed to investigate the overall mechanical behavior and the interfacial microcrack evolutions of the cementitious composites featuring superabsorbent polymer (SAP) under uniaxial tension. Elastic properties, progressive damage process, and homogenization procedure of cementitious composites are systematically integrated in this model. The effective elastic moduli of the composites are determined based on a multiscale micromechanical framework. According to the small strain assumption, the total strain tensor and the elastic-damage compliance tensor are additively decomposed into elastic and damage-induced components. The damage-induced strains and compliances are then deduced from micromechanics. To characterize the progressive elastic-damage induced by microcracks, stages of microcrack propagation are identified from the interface contact stress and the matrix cleavage stress. The complex potentials and stress intensity factors for kinked interface cracks are derived from the distributed dislocations method. By implementing the homogenization process, the macroscopic mechanical behavior is obtained from the micro/mesoscale. The results indicate that the material parameters have clear mechanical significance. Different parameters, such as the SAP addition ratio, aggregate content, initial interfacial crack size, and initial interfacial crack location, are revealed to be influential in the overall mechanical behavior of the composites. The proposed model can be generalized to other particle-reinforced composites with different constituent properties, which can potentially contribute to the design and optimization of durable composites.

Ju J, Wang N, Wang J, Wu F, Ge J, Chen F. Drug Des Devel Ther. 2018;12:997-1008. At the request of the authors, the Editor and Publisher of the journal Drug Design, Development and Therapy have retracted the published article. Following publication of the article, the authors raised concerns about the duplication of images from Figure 2 with those from an unrelated article and the duplication of images within Figure 8. Specifically, Images from Figure 2B, MDA-MB-453 and MDA-MB-231, have been duplicated with the same images for Figure 2F and 3I from Dong SR, Ju XL, Yang WZ. STAT5A reprograms fatty acid metabolism and promotes tumorigenesis of gastric cancer cells. Eur Rev Med Pharmacol Sci. 2019;23(19):8360-8370. https://doi.org/10.26355/eurrev_201910_19147. Images for Figure 8, FL-/siRNA+ and FL+/siRNA-, 0 h; FL-/siRNA- and FL-/siRNA+, 12 h; FL-/siRNA-, 24 h and FL-/siRNA+, 48 h; and FL-/siRNA-, 48 h and FL+/siRNA-, 24 h, have been duplicated. The corresponding author was cooperative and responded to our queries but was unable to provide a satisfactory explanation for how the images came to be duplicated or provide satisfactory original data for the study. As verifying the validity of published work is core to the integrity of the scholarly record, the authors requested to retract the article and the Publisher and Editor agreed with this decision. We have been informed in our decision-making by our editorial policies and COPE guidelines. The retracted article will remain online to maintain the scholarly record, but it will be digitally watermarked on each page as “Retracted”.

An energy‐based isotropic elastoplastic damage model is developed for investigating the elastoplastic damage responses and stress–strain relationships of nano‐silica incorporated concrete. The formulation employs a multiscale micromechanical framework to determine the effective elastic properties of composites at different scales. The stress–strain constitutive relation is derived by splitting the strain tensor into "elastic‐damage" and "plastic‐damage" parts while introducing the homogenized free potential energy function and the undamaged potential energy function. The elastoplastic damage response of the material is further characterized by elastic–plastic‐damage coupling. To construct realistic 3D three‐phase concrete mesostructures in numerical simulations, this paper introduces an encapsulation placement method that avoids particle overlap checking when placing aggregates. This methodology allows adjustments for the aggregate compactness as needed and enhances computational efficiency in concrete mesostructure construction. The numerical results of the modeling show good agreement with the experimental values in the open literature. Further, the influence of nano‐silica addition contents and ITZ (interfacial transition zone) thicknesses on the elastoplastic damage response of nano‐silica incorporated concrete are quantitatively and qualitatively investigated for the optimization of nano‐silica incorporated cementitious composites. The proposed model facilitates simulating and optimizing the mechanical characteristics of nano‐silica incorporated concrete and enhances the computational efficiency of 3D concrete modeling with the introduced encapsulation placement method. [ABSTRACT FROM AUTHOR]

During this study, an indoor experiment was conducted to determine the effect of mixed seeding rates of legumes used as green manure on the substrate fertilizer, growth characteristics, and bioactive compounds of baby leaf vegetables. The mixed seeding treatment was designed for milkvetch (Astragalus sinicus L.), tatsoi (Barassica rapa L.), kale (Brassica oleracea var. sabellica L.), and spinach (Spinacia oleracea L.) using five rates for each. Accordingly, a total of 15 treatments (3 baby leaf species × 5 mixed seeding rates) were constructed using a randomized complete block design with three replications for each treatment. During the baby leaf vegetable harvest, we evaluated the macronutrient levels (nitrogen, phosphorus, and potassium) in the substrate as well as the growth parameters and carotenoid contents. The substrate in the treatment mixed with milkvetch showed significantly higher levels of nitrogen, phosphorus, and potassium compared with those of tatsoi and kale sown alone (P ≤ 0.05). However, there were no significant differences in macronutrients observed in substrate-sown spinach with or without the milkvetch mixture. The growth and carotenoid levels of each baby leafy vegetable sown alone were significantly higher than those of each baby leafy vegetable sown with the mixed seeding treatment (P ≤ 0.05). Sowing the milkvetch-vegetable mixtures did not result in a significant increase in the growth and carotenoid levels of the three baby vegetables. The results showed that planting milkvetch with tatsoi and kale had a significant impact on substrate fertilization. However, regarding short-term vertical indoor farming, the growth and carotenoid responses of the three greens may be different. Nonetheless, we still believe that the combined interactions of legumes can provide long-term benefits by enhancing the biological functionality of the growing medium for balanced indoor agriculture production. [ABSTRACT FROM AUTHOR]