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In this paper, zinc calcines, sulfuric acid, ferric nitrate nine-hydrate, zinc nitrate hexahydrate, titanium oxide sulfate, sodium hydroxide and ammonia water were selected as raw materials, and the methods of sulfuric acid leaching and chemical coprecipitation were used to prepare purified zinc ferrite, synthetic zinc ferrite, synthetic titanium dioxide and its composite with purified zinc ferrite. And characterized by BET, UVVis and FTIR. The results showed that: SO42- existed in purified zinc ferrite. Purified zinc ferrite, synthetic zinc ferrite and purchased had different specific surface area, pore volume and average pore size. The specific surface area of synthetic zinc ferrite decreased with the increase of calcination temperature. The three kinds of zinc ferrite had good absorption of ultraviolet light and visible light. Purchased ferric acid had the strongest absorption of UV light and synthetic zinc ferrite had the strongest absorption of visible light, and purified zinc ferrite had the absorption of UV light and visible light between the two. The specific surface area of titanium dioxide prepared by chemical coprecipitation method was greatly affected by calcination temperature. With the increase of calcination temperature, the specific surface area decreased from 123.633 to 28.036m2·g-1, and the average pore diameter was less affected by calcination temperature. For the zinc ferrite/titanium dioxide composite prepared by chemical coprecipitation method, a certain amount of purified zinc ferrite was added to facilitate the absorption of visible light by titanium dioxide.

In this paper, sulfuric acid leaching high iron zinc calcine was used to prepare and purify zinc ferrite, high temperature roasting method was used to prepare synthetic zinc ferrite, and sol-gel method was used to prepare TiO2. The properties of the prepared samples ware characterized by XRD, FT-IR, BET, SEM and other methods. The results show that the synthetic zinc ferrite is pure zinc ferrite, and the purified zinc ferrite contains impurities PbSO4. The TiO2 crystal form prepares at the calcination temperature of 300~550°C is basically the same, and the crystal form transformation occurs at the calcination temperature of 550~600°C. TiO2 samples calcines at 400°C (T400) have higher specific surface area, larger total pore volume and average pore diameter. The crystalline degree of synthetic zinc ferrite is high, the micropores on the crystal surface are closed, and the grains bond with each other. The specific surface area, total pore volume and average pore diameter of purified zinc ferrite are larger than those of synthetic zinc ferrite. The effects of specific surface area, pore volume and pore structure on the adsorption capacity and catalytic efficiency are as follows: T400> purified zinc ferrite > synthesized zinc ferrite.

In this paper, the methods of sulfuric acid leaching and chemical coprecipitation were used to prepare products such as purified zinc ferrite, synthetic zinc ferrite, synthetic titanium dioxide and its complex with purified zinc ferrite. The morphology and microstructure of the above samples were characterized and analyzed by XRD and SEM. The results showed that the purified zinc ferrite contained a small amount of ZnO, SiO2, Al2O3 and PbSO4. Its particle size was the largest and the crystallinity was the best, but the surface was not smooth, the particle size distribution was not uniform and there was agglomeration phenomenon. The purchased zinc ferrite had high purity, the smallest particle size and the worst crystallinity. Its surface was smooth, particle size distribution was uniform, and it was loose and porous. The synthetic zinc ferrite had high purity, smooth surface, uniform particle size distribution and obvious agglomeration. The prepared titanium dioxide had no other impurities, good crystallinity, smooth surface and certain agglomeration phenomenon. For the zinc ferrite/titanium dioxide composite, adding a small amount of purified zinc ferrite would change the crystallinity of titanium dioxide, but it had little effect on the grain size of titanium dioxide. The surface was rough, the particle size distribution was not uniform, and there was agglomeration phenomenon.

The Bayer red mud generated from the alumina industry is a hazardous solid waste. In our team, a green calcification–carbonation process is proposed for its disposal. Red mud is treated with lime to convert the silicon phase in solution into hydrogarnet, which is then decomposed by CO2 to recover alumina. In order to simplify the process flow, the direct carbonation process is employed, in which the NaOH-containing solution resulting from calcification is sent directly to carbonation without prior liquid–solid separation. The discrete and direct carbonation processes gave 34.9% and 35.5% alumina recoveries, respectively, with Na2O contents in the final red muds of 0.15%wt and 0.21%wt, respectively. The optimum NaOH concentration in the whole calcification–carbonation process liquor was 40 g/l. Under this alkali condition, alumina recovery reached 40.5% and the Na2O content in the processed red mud was reduced to

In response to the occurrence of selective grinding phenomena in polymetallic complex ores and the lack of associated research on complex ores and their constituent minerals, an investigation was conducted based on the motion theory of grinding media and the principles of selective grinding. The grinding characteristics were elucidated using metrics such as the breakage rate, grinding speed, and the t10 parameter of the ground product. The relationship between the grinding characteristics of polymetallic complex ores and their component mineral, including pyrrhotite, sphalerite, and quartz, under throw grinding conditions was investigated. The results show that during dropping state, sphalerite enhances the ore comminution effect, indicating that the presence of sphalerite plays a positive role in ore crushing, whereas pyrrhotite and quartz diminish the ore comminution effect, meaning their presence exerts a negative influence on ore crushing. The particle size characteristics of the grinding products of different constituent minerals all affect the particle size characteristics of the ore grinding products, with sphalerite showing a more significant impact on the ore's grinding characteristics. The grinding rate of both the ore and its constituent minerals exponentially decreases with prolonged grinding time, reaching a threshold when the grinding time reaches 4 minutes, where the rate of decrease rapidly slows. These findings can provide theoretical guidance for subsequent research on the optimization and control of grinding polymetallic complex ores under throw grinding. [ABSTRACT FROM AUTHOR]

Aiming at the problems of cassiterite overgrinding and sulfide minerals undergrinding in the grinding process of cassiterite polymetallic sulfide ore, this paper investigated the influence of grinding time, mill filling rate and other factors on the particle size distribution of grinding products and the efficiency of grinding technology based on the conditions of different grinding media. The results show that grinding times positively correlated with the yield of qualified and overgrinding particles in the grinding products, and negatively correlated with the yield of undergrinding particles, and the content of Φ20 mm steel balls in the combination of steel bals in the grinding media has a greater impact on the qualified and overgrinding particles, and has a smaller impact on the undergrinding particles. Grinding time has a greater impact on the efficiency of grinding technology, when the grinding times certain the higher the content of Φ20 mm steel balls in the media combination, the higher the efficiency of grinding technology. Mill filling rate and grinding products in the qualified particle yields positively correlated but the impacts less than the grinding time, grinding media ball combination of Φ20 mm steel ball content has a greater impact on this law whereas the impact of filling rate on yields of over-grinding and under-grinding particles is small. Mill filling rate has a certain effect on the efficiency of grinding technology, when the mill filling rates certain the higher the content of Φ20 mm steel bals in the media combination the higher the efficiency of grinding technology. The results of the study can provide reference for the optimization of grinding media in cassiterite polymetallic sulfide ore filling production and mitigation of cassiterite overgrinding and sulfide ore undergrinding. [ABSTRACT FROM AUTHOR]

Proton pump inhibitors (PPIs) are some of the most commonly prescribed drugs worldwide, but there are increasing concerns about digestive complications linked to PPIs. Next-generation sequencing studies have suggested that PPIs can significantly affect the composition of the gut microbiota, which in turn may substantially contribute to the development of these complications. Recently, emerging evidence has suggested that the translocation of oral microbes into the gut may be the primary mechanism underlying the alterations in the gut microbiota induced by PPIs in the presence of gastric acid suppression and impaired oral–gut barrier function. Moreover, the significance of oral–gut microbial translocation in health and disease conditions has gained increasing recognition. Consequently, it is imperative to enhance our understanding of the functions of the oral–gut microbiota axis in digestive disorders associated with PPI therapies. This review aims to summarize current research findings and further elucidate the contribution of the oral–gut microbiota to the pathogenesis of PPI-related digestive diseases. We aim to provide a theoretical foundation for future therapeutic and preventive strategies targeting PPI-related digestive complications through modulation of the oral–gut microbiota. [ABSTRACT FROM AUTHOR]