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Enhanced sulfurization has always been the focus of research on the flotation of copper oxide minerals. In this study, combined ammonium–amine salts were innovatively applied to improve the sulfurization of azurite. Flotation tests were carried out to evaluate the promoting effect of ammonium–amine co-activation on the sulfurization–xanthate flotation of azurite, and the microstructure evolution of sulfurized products was investigated to reveal the mechanism underlying this promoting effect. Compared with single ammonium (amine) salt activation, ammonium–amine co-activation improved the floatability of azurite to a greater extent, i.e., the flotation recovery increased by over 4 percentage points. ToF-SIMS, ICP-OES, FESEM-EDS, AFM, XRD, and UV-vis analyses indicated that ammonium–amine co-activation combined the advantages of inorganic ammonium for buffering pH and organic amine for copper ion complexation, thus promoting the growth of sulfurized crystal products (covellite) and enhancing the adhesion stability of sulfurized products on azurite. Therefore, increasing amounts of copper sulfide components were generated under the ammonium–amine–Na2S system, promoting the adsorption of additional xanthate on azurite. This study provides theoretical support for the application of combined ammonium–amine salts for the sulfurization flotation of copper oxide. [ABSTRACT FROM AUTHOR]

Research on the dissemination characteristics, mineral composition and particle size distribution of the ore of west mine in Bayan Obo under the condition that the grinding fineness is 92.27% of -0.074 mm is conducted by means of mineral liberation analyzer and chemical analysis, etc. According to the mineralogical characteristics of ore and the feasibility of industrial beneficiation flowsheet, the principle flowsheet is formulated and the condition optimization test is carried out. On this basis, a rare earth rougher concentrate with REO grade of 10.17% and recovery of 86.15% was obtained through rare earth flotation open circuit test using a new rare earth collector CMS-1 and depressant CAM-1. A fluorite concentrate with CaF2 grade of 90. 80% and recovery of 33.00% was obtained by using a new fluorite collector CMK-3 and depressant CMP-1 and CMP-3 through a small closed circuit test in the laboratory, which provides a theoretical basis for the separation of the same type of ores. [ABSTRACT FROM AUTHOR]

Background: Ulcerative colitis (UC) is a prevalent case which needs more detailed exploration. We attempted to illustrate how miR-223-3p acted in the development of UC. Materials and Methods: The level of miR-223-3p in serum from UC patients was detected using quantitative reverse-transcriptase polymerase chain reaction. The in vivo experimental spleen-kidney-yang deficiency mice model was established to get a better understanding of the action of miR-223-3p in UC development. Hematoxylin and eosin staining was applied to observe the intestinal epithelial barrier function. Western blotting was applied to measure the expression of ZO-1, Occludin, TGF-β, and Smad3. Results: Enrichment of miR-223-3p was observed in serum from UC patients. miR-223-3p antagomir could lower the shortening of colon length, alleviating the intestinal epithelial barrier function damage caused by UC. Under the UC conditions, TNF-α, IL-6, and IL-1β were up-regulated, whereas with the miR-223-3p antagomir, the up-regulation was less pronounced; ZO-1 and Occludin protein levels were decreased, whereas the decrease was less obvious in the miR-223-3p antagomir group. Additionally, miR-223-3p regulated UC development through the TGF-β/Smad3 pathway. Conclusion: miR-223-3p promoted UC development with spleen-kidney-yang deficiency through the TGF-β/Smad3 pathway. [ABSTRACT FROM AUTHOR]

[Display omitted] • The first application of TMT in the study of malachite activation flotation. • TMT activated malachite at low alkalinity and low dose, and obtain higher recovery. • The high dosage of TMT had no exert inhibitory effect on malachite. Malachite is a typical refractory copper oxide mineral. In this paper, trithiocyanuric acid (TMT) was used as a novel activator for the activated flotation of malachite for the first time. The effect of TMT on the flotation behavior of malachite was studied and the activation mechanism was discussed. The flotation test results showed that TMT exhibited superior activation performance over sodium sulfide, achieving a high flotation recovery rate of 97.50 % at TMT 90 mg/L and pH 7. The contact angle confirmed malachite improved from 53.3° to 90.1° after TMT treatment, indicating enhanced hydrophobicity of the mineral surface. FTIR and EDS analyses provided clear evidence of chemical adsorption of TMT tautomers onto the malachite surface. SEM images further illustrated the presence of dense particles formed after TMT treatment. XPS revealed that TMT exhibited a strong adsorption effect on malachite, leading to an increase in copper sites and the formation of highly reactive Cu+. The activation mechanism was elucidated as the reaction between Cu sites on malachite and S and N atoms in TMT, forming Cu-S and Cu–N fractions crucial for activation. The high efficiency and low dosage of TMT make it a promising activator for malachite, offering a novel avenue for the effective recovery of malachite-type copper oxide ore resources. [ABSTRACT FROM AUTHOR]

Objective To compare the efficacy and safety of combining diosmin with Jiuhua hemorrhoid suppository versus diosmin alone for the treatment of hemorrhoid hemorrhage. Methods The Jiuhua hemorrhoid suppository study was conducted in 10 medical centers across China from April 1, 2019 to June 30, 2020. Patients with hemorrhoid bleeding were randomized in a ratio of 1: 1 to either receive Jiuhua hemorrhoid suppository and diosmin tablets (the study group) or diosmin tablets alone (the control group). The suppository was used once a day after defecation or at bedtime after rinsing the anus with warm water. Diosmin tablets were administered only once a day (0.9 g). The primary endpoint of the study was the assessment of hemorrhoid bleeding relief 7 ± 2 days after treatment, classified as "very effective" "effective" and "ineffective". The secondary endpoint included the evaluation of pain alleviation using the visual analogue scale (VAS, with scores ranging from 0 to 10) and edema (with scores ranging from 0 to 3). The safety of the two treatment regimens was evaluated 14 ± 2 days after drug administration. Results The full analysis set (FAS) comprised 107 participants in the study group and 111 in the control group, while the per-protocol set (PPS) included 106 participants in the study group and 111 in the control group. In terms of hemorrhoid bleeding, the proportion of very effective and effective cases in the study group were significantly higher than that in the control group [106 (99.06%) vs. 91 (81.98%), P < 0.000 1] in the FAS, and the PPS results [105 (99.06%) vs. 91 (81.98%), P < 0.000 1] were comparable to the FAS results. The pain VAS scores at day 7 after treatment were comparable between the two groups (0.80 ± 1.17 vs. 0.80 ± 1.20, P = 0.217 7). The majority of the participants in both groups had an edema score of 0 at day 7 after treatment [96 (89.72%) vs. 99 (91.67%), P = 0.370 5]. Adverse events (AEs) occurred in 9 patients (8.4%) in the study group and 3 patients (2.7%) in the control group. In addition, 5 AEs in the study group and 1 AE in the control group were possibly in association with the study drug. Conclusion Compared with the administration of diosmin oral tablets alone, the addition of Jiuhua hemorrhoid suppository to the tablets demonstrates enhanced efficacy in addressing hemorrhoid bleeding, with satisfactory patient adherence and acceptable safety. [ABSTRACT FROM AUTHOR]

• Na 2 S modifies CuO by creating Cu-S bonds on its surface. • Cu(Ⅰ)-S and S n 2− species are the main active components. • Na 2 S-modification CuO adsorbs more BX−, and improves the recovery performance. • Strong hydrophobic interaction forces between CuO particles and bubbles. Copper smelting slag (CS), which is often overlooked, is a valuable solid-waste resource for reclaiming copper. Flotation is the most cost-effective method for its recovery. While most of the copper fraction can be easily recovered utilizing xanthate collection. However, the recovery effect of copper oxide components is poor, resulting in the waste of a large amount of copper resources. The sulfidization-xanthate method has exhibited some efficacy in recovering CS, due to its high economic value. However, the mechanism of using this method to recover CuO from CS is still unclear. This study utilized CuO samples to explore the recovery mechanism of the copper oxide fraction in CS within the sulfidization-xanthate system. Density-functional theory (DFT) theory and X-ray photoelectron spectroscopy (XPS) elucidated the sulfidization mechanism on the CuO surface, revealing the S formation of a Cu-S chemical bond on the CuO surface via chemisorption. Cu(I)-S and S n 2−, are the key species in activating CuO. Thermogravimetry analysis (TGA) identified that the CuO sulfidized surface adsorption less water than CuO surface. Zeta potential, ultraviolet visible (UV) and fourier transform infrared (FT-IR) tests illustrated the adsorption of sodium butyl xanthate (SBX) collection, exhibiting increased xanthate adsorption after Na 2 S treatment. Molecular dynamics (MD) simulation indicated the relative concentration of water molecules on the surface of CuO sulfidized had decreased, while the SBX had increased. Flotation tests confirmed the recoverability of CuO using this method. The extended Derjaguin Landau Verwey Overbeek (EDLVO) theory illustrates that the adhesion between the CuO particles and bubbles is promoted. Overall, the sulfidization-xanthate method can enhance the recovery of CuO and provide theoretical guidance for practical production. It also lays the theoretical foundation for future studies. [ABSTRACT FROM AUTHOR]

Galena separation from chalcopyrite poses a notable challenge in mineral processing, owing to the involvement of high dosages of traditional process reagents and substantial environmental impact. This study addresses this challenge by introducing 2,5-dimethoxy-1,3,4-thiadiazole (DMTD) as a chalcopyrite depressant using sodium ethyl xanthate (NaEX) as a collector. X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) analyses showed that DMTD can be adsorbed on the surfaces of chalcopyrite and galena, but the adsorption on chalcopyrite is stronger than that on galena. UV–vis, zeta potential and time-of-flight secondary ion mass spectrometry (ToF-SIMS) analyses revealed that DMTD impeded the adsorption of NaEX on chalcopyrite; moreover, NaEX could desorb the DMTD adsorbed on galena and re-adsorb it on galena. Surface hydrophilicity tests revealed that DMTD significantly enhanced the hydrophilicity of chalcopyrite in the presence of NaEX, and galena was selectively separated from chalcopyrite using 1×10− 4 mol/L DMTD at pH exceeding 5. The recovery of galena remained >90 %, while that of chalcopyrite drastically decreased to <5 %. Furthermore, artificial-mixing experiments confirmed the separation effect of DMTD as a chalcopyrite depressant. Notably, this study avoids environmental pollution caused by traditional depressants, offering a potential green approach to achieve effective flotation separation of copper–lead sulfide ore. [Display omitted] [ABSTRACT FROM AUTHOR]

The full activation of azurite, which is a key mineral of copper oxide, has considerable potential for efficient Cu recovery. 2,5-Dimercapto-1,3,4-thiadiazole (DMTD) is an effective azurite activator. The floatability of azurite is inevitably inhibited severely with increasing concentration of its activator. For a long time, improving the activation of the azurite surface and mitigating the inhibition effects of excessive activators have been crucial for enhancing the recovery of copper oxide minerals. In this study, the evolution and regulation mechanism of the NH 3 ·H 2 O–DMTD activation system on azurite surface products are systematically examined. In this system, although the elemental composition of the activation products remained unchanged, their adhesion stability on azurite was considerably enhanced and the number of Cu active sites on azurite was increased, greatly promoting the adsorption of the collector such that azurite was more hydrophobic and floats. An actual flotation test on copper oxide ores reveals that the Cu grade and recovery increase by 0.49 % and 4.69 %, respectively, via NH 3 ·H 2 O–DMTD synergistic activation. This study combines theoretical and practical approaches to further explain the influence of NH 3 ·H 2 O–DMTD on the surface modification and flotation interface characteristics of azurite, providing a basis for subsequent industrial applications. [Display omitted] • Pretreatment with NH 3 ·H 2 O increased the activation of azurite by DMTD. • The inhibition of flotation by high concentrations of DMTD was alleviated. • The grade and recovery of the CuO flotation concentrate were enhanced. • The adhesion stability of products and flotation environment were enhanced. [ABSTRACT FROM AUTHOR]

• Elucidate the copper activation on depressed-sphalerite under moderate alkaline conditions. • DFT verify that coppers have two action behaviors in activating depressed-sphalerite. • DFT simulations confirm the stability of interaction between Cu ions and S. • Excessive copper ions will consume some of the collector BX and affect flotation. Currently, extensive research exists on the activation mechanisms of sphalerite, yet there is a notable absence of studies on the mechanisms behind the activation of depressed sphalerite. This paper investigates the mechanism through which moderate or excessive copper ions activate depressed sphalerite under conditions (pH 9–10) of moderate alkalinity, employing a comprehensive approach that includes pure mineral flotation experiments, contact angle measurements, FESEM-EDS, XPS, and density functional theory simulations. The results from pure mineral flotation experiments reveal that, at a copper ion concentration of 1 × 10−4 mol/L, sphalerite, previously depressed by zinc sulfate, is activated by copper ions, achieving a recovery rate of 91.46 % with butyl xanthate as the collector. However, when more cooper ions are added, the recovery of sphalerite decreases. Contact angle measurements and FESEM-EDS data indicate that under conditions of moderate alkalinity, zinc sulfate undergoes hydrolysis to form hydrophilic colloidal substances (hydroxylated zinc) that adhere to the surface of sphalerite, rendering it hydrophilic and thereby depressed. Following the introduction of copper ions, a dense striated material forms on the surface of sphalerite previously inhibited by zinc sulfate, enhancing its hydrophobicity, but if more copper ions were added, the hydrophobicity of activated sphalerite will be weakened. XPS findings further suggest that activated sphalerite by copper is capable of forming polysulfides, which then act on the sphalerite. DFT simulations verify that under moderate alkalinity conditions, copper ions first undergo a hydroxylation reaction in the solution before adsorbing or precipitating on the mineral surface as hydroxylated substances, which subsequently interact with sulfur on the surface of sphalerite. The analysis of the density of states indicates that following the addition of butyl xanthate, the strongest 3p orbital electron peak of the sulfur atom bound to butyl xanthate and the strongest 3d orbital electron peak of zinc are at distinct energy levels, suggesting that the overlap of the electronic density of states is minimal, indicating a weak and unstable interaction between the sulfur and zinc atoms bonded with butyl xanthate. Conversely, the strongest 3p orbital electron peak of the sulfur atom bonded with butyl xanthate overlaps with the strongest 3d orbital electron peak of copper and is positioned near the Fermi level, signifying a strong reactivity and more stable interaction between the sulfur and copper atoms. [ABSTRACT FROM AUTHOR]

• Temperature-controlled sulfuric acid pre-oxidation enhances the separation of galena and chalcopyrite. • Sulfuric acid recycling reduces acid consumption and environmental impacts. • Increased pre-oxidation temperature decreases galena floatability. • Explain the relationship between the independent variable temperature and thermodynamic and electrochemical processes. Galena and chalcopyrite pose challenges in their separation owing to their similar surface chemistry. The flotation separation of galena and chalcopyrite significantly depends on the use of depressants. However, conventional depressants are often associated with several drawbacks, such as toxicity and inefficiency. Hence, exploring efficient and environmentally friendly techniques to separate galena and chalcopyrite is vital. This study investigated the use of sulfuric acid as a surface oxidant for the pre-oxidation treatment of galena and chalcopyrite at high temperatures. This approach facilitated acid recycling and eliminated the need for multiple flotation chemicals. The floatability of galena and chalcopyrite was investigated through micro-flotation. The results revealed that at a pre-oxidation temperature of 100℃, galena exhibited a recovery rate of only 9.98 %, while chalcopyrite maintained a recovery rate of 96 % across the temperature range. The selective depressant mechanism of sulfuric acid in the flotation separation of galena and chalcopyrite was investigated through scanning electron microscopy, zeta potential measurements, X-ray photoelectron spectroscopy, thermodynamic calculations, and electrochemical analyses. The results indicated that the high temperature facilitated the dissolution of the sulfide layer on the galena surface. Consequently, S2− ions underwent oxidization into SO 4 2− to form a stable oxide film on the galena surface through interaction with Pb2+. Conversely, the high-temperature pre-oxidation had a minimal effect on the surface of chalcopyrite, indicating selective oxidation benefits. Findings from the pre-oxidation floatation separation test of galena–chalcopyrite mixtures revealed the efficient and thorough separation of the two minerals under high-temperature pre-oxidation conditions. The lead concentrate obtained from the floatation process exhibited a Pb grade of 79.38 % and a recovery rate of 97.17 %, while the Cu concentrate featured a Cu grade of 32.14 % and a recovery rate of 97.06 %. Additionally, the sulfuric acid solution was recycled. Overall, this study provides a sustainable and cost-effective approach for the green separation of copper–lead sulfide ores. [ABSTRACT FROM AUTHOR]