Optimizing the dewatering performance of zinc smelting iron Slag: Investigating the influence of ultrasonic Time, ultrasonic Power, and Liquid-Solid ratio using response surface methodology.

Iron slag, a byproduct of the wet zinc refining process, contains a substantial amount of valuable metals such as iron and zinc, making it highly valuable for comprehensive recovery and reuse. However, before recovery, the iron slag requires dehydration pretreatment. The water content in iron slag remains relatively high and difficult to remove even after pressure filtration, leading to extended drying times, reduced drying efficiency, and increased energy consumption. This study explores a novel ultrasonic pretreatment process for iron slag. Using the response surface methodology, we investigated the effects of ultrasonic power, ultrasonic time, liquid-to-solid ratio, and their interactions on the water content, capillary suction time (CST), and filtration resistance of the slag. Regression equations were established to predict the relationships between the water content, CST, filtration resistance, and the various factors. The optimal process parameters were determined as an ultrasonic power of 60 W, ultrasonic time of 22 s, and a liquid-to-solid ratio of 4:1. Under these conditions, the dehydration performance of the iron slag was optimal. The measured values closely matched the predicted values, demonstrating the reliability of the model and the feasibility of the optimized process. Our study of the mechanism of ultrasonic action on iron slag found that under the influence of ultrasonic waves, the particle size of the slag significantly decreased, and the particle morphology changed. Compared to conventional drying, the drying rate of the iron slag after ultrasonic pretreatment was accelerated, and the drying time was reduced.

Study on the Drying Kinetics of Zinc Smelting Iron Slag Assisted by Ultrasonic Waves.

This study investigates the impact of ultrasonic treatment on the drying kinetics of zinc smelting iron slag. Through the Arrhenius equation, it was found that the reaction order of zinc smelting iron slag remains constant at 1/2 before and after ultrasonic treatment, indicating a proportional relationship between the reaction rate and the square root of the reactant concentration. Despite the increased drying rate of the iron slag due to ultrasonic pretreatment, the reaction order remains at 1/2. Additionally, it was observed that the drying kinetics of untreated iron slag aligns with the Wang and Singh model, while the drying kinetics of ultrasonically pretreated iron slag fits the Page model. The Page model facilitates the prediction of drying rate and drying time for ultrasonically pretreated iron slag, enabling the optimization of the drying process, enhancing efficiency, and comparing drying performance under different conditions. Using ultrasonic pretreatment, the subsequent drying process of iron slag can significantly shorten the time and save energy. These findings provide essential theoretical foundations for optimizing the drying process of zinc smelting iron slag.

Identification of QTLs and Putative Candidate Genes for Plant Architecture of Lotus Revealed by Regional Association Mapping.

The lotus (Nelumbo Adans.) is one of the most economically relevant ornamental aquatic plants. Plant architecture (PA) is an important trait for lotus classification, cultivation, breeding, and applications. However, the underlying genetic and molecular basis controlling PA remains poorly understood. In this study, an association study for PA-related traits was performed with 93 genome-wide microsatellite markers (simple sequence repeat, SSR) and 51 insertion-deletion (InDel) markers derived from the candidate regions using a panel of 293 lotus accessions. Phenotypic data analysis of the five PA-related traits revealed a wide normal distribution and high heritability from 2013 to 2016, which indicated that lotus PA-related traits are highly polygenic traits. The population structure (Q-matrix) and the relative kinships (K-matrix) of the association panels were analyzed using 93 SSR markers. The mixed linear model (MLM) taking Q-matrix and K-matrix into account was used to estimate the association between markers and the traits. A total of 26 markers and 65 marker-trait associations were identified by considering associations with p < 0.001 and Q < 0.05. Based on the significant markers, two QTLs on Chromosome 1 were identified, and two candidate genes were preliminarily determined. The results of our study provided useful information for the lotus breeding aiming at different PA phenotypes using a molecular-assisted selection (MAS) method and also laid the foundation for the illustration of the molecular mechanism underlying the major QTL and key markers associated with lotus PA.

Defluorination study of spent carbon cathode by microwave high-temperature roasting.

Spent carbon cathode (SCC) produced in the process of aluminum electrolysis is a typical toxic and hazardous solid waste. Therefore, the harmless treatment of SCC is extremely important for the green development of aluminum electrolysis industry. In this paper, the microwave-assisted high-temperature roasting technology was developed to remove fluorides in SCC for recycling of this cathode. The melting point, dielectric parameter, crystalline structure, surface chemical property, elemental composition, morphological structure, carbon graphitization and surface area were characterized using thermogravimetric analysis and differential scanning calorimetry, high-temperature composite conductivity analyzer, X-ray diffraction, X-ray fluorescence, X-ray photoelectron spectroscopy, scanning electronic microscopy, transmission electron microscopy, Raman spectroscopy and isothermal N2 adsorption-desorption method. The content of fluorides in raw and treated SCC was measured by ion activity meter. The results showed that the phase of sodium fluoride and cryolite would transform from solid to liquid when the temperature was higher than 1098.5 °C, and the SCC exhibited good performance on wave absorption with the action depth of 1 cm. The SCC was mainly composed of 57.94 wt% C, 14.23 wt% NaF, 1.80 wt%, CaF2, 15.06 wt% Na3AlF6, and 10.97 wt% Other. After treatment under microwave, the graphite carbon exhibited pitting structure and the fluorides could be effectively removed. In addition, the average layer spacing of graphite was increased from 0.34 to 0.36 nm. The defluorination of SCC could be enhanced with the increase of roasting temperature, which would attain 95.4% at 1500 °C. Compared with the traditional roasting method, the process under microwave showed more defects, which would provide a new guidance for the treatment and recycling of spent SCC.

Competitive coordination of the dual roles of the Hedgehog co-receptor in homophilic adhesion and signal reception.

Hedgehog (Hh) signaling patterns embryonic tissues and contributes to homeostasis in adults. In Drosophila, Hh transport and signaling are thought to occur along a specialized class of actin-rich filopodia, termed cytonemes. Here, we report that Interference hedgehog (Ihog) not only forms a Hh receptor complex with Patched to mediate intracellular signaling, but Ihog also engages in trans-homophilic binding leading to cytoneme stabilization in a manner independent of its role as the Hh receptor. Both functions of Ihog (trans-homophilic binding for cytoneme stabilization and Hh binding for ligand sensing) involve a heparin-binding site on the first fibronectin repeat of the extracellular domain. Thus, the Ihog-Ihog interaction and the Hh-Ihog interaction cannot occur simultaneously for a single Ihog molecule. By combining experimental data and mathematical modeling, we determined that Hh-Ihog heterophilic interaction dominates and Hh can disrupt and displace Ihog molecules involved in trans-homophilic binding. Consequently, we proposed that the weaker Ihog-Ihog trans interaction promotes and stabilizes direct membrane contacts along cytonemes and that, as the cytoneme encounters secreted Hh ligands, the ligands trigger release of Ihog from trans Ihog-Ihog complex enabling transport or internalization of the Hh ligand-Ihog-Patched -receptor complex. Thus, the seemingly incompatible functions of Ihog in homophilic adhesion and ligand binding cooperate to assist Hh transport and reception along the cytonemes.