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This study describes the first, use of eco-friendly welan gum as a new depressant in galena-pyrite flotation separation. The depression mechanism were examined using micro-flotation and various characterization techniques. The selective depression performance of welan gum on pyrite was found to effectively enhance the galena/pyrite flotation separation index. Compared with the addition of NaBX alone, the grade of Pb in the produced concentrate increased by more than 28% (from 40.86% to 70.02%). And it was possible to recover 87.79% of galena and only 15.98% of pyrite. There was an accentuated increase in the electronegativity of the pyrite surface by more than ~ 8 mV after treatment with welan gum alone compared to an increase of ~ 1 mV for galena, which can be explained by the fact that welan gum selectively adsorbed on the pyrite surface in significant amounts. As a result, the subsequent adsorption of xanthate is prevented. This finding has been further proven by adsorption measurement results. The X-ray photoelectron spectroscopy and Time-of-Flight secondary ion mass spectrometry results indicated that the hydroxyl groups in welan gum showed acid – base interactions with the metal hydroxylated species anchored on the mineral surfaces, which may be the main driving force in the adsorption process. Differences in the amount of metal hydroxide on the mineral surface, as well as the electrical affinity of metal ions in metal hydroxide, contributed to the selective adsorption of welan gum. Therefore, welan gum can be regarded as a potential pyrite-depressant. [ABSTRACT FROM AUTHOR]

The purpose of this study is to evaluate the effect of blue light and its brightness on long-term memory. Blue light was tested under four distinct illuminance conditions ranging from 400 to 1000 lux, and the results were compared with those of red light as a comparison group. A total of 25 individuals, including 16 men and 9 women with a mean age of 22.04 ± 1.74 years, participated in these tests based on a within-subject research design. Initially, each participant was exposed to individual light conditions for 30 min in the morning. Subsequently, they were asked to complete learning memory tasks, which involved memorizing specific words composed of randomly chosen English consonants. Exactly 20 min after these memory tasks, their long-term memory retention was measured through recall. It was found that blue light was superior to red light in terms of long-term memory enhancement; the difference was statistically significant, with a confidence level of 95%. Moreover, brighter light environments were found to affect long-term memory performance more significantly compared to darker light environments. That said, there was no significant difference in interaction effects between light color and brightness. These findings confirm the results of previous studies highlighting the effectiveness of blue light in enhancing memory retention while also demonstrating that the degree of enhancement may vary depending on light brightness. [ABSTRACT FROM AUTHOR]

Tetrahedrite-(Cd), Cu10Cd2Sb4S13, is a member of the tetrahedrite series of the tetrahedrite group with a predominance of Cd at the C position typically occupied by divalent metals. Cadmium end-members from the tetrahedrite group are rare: they have been described in 15 deposits and ore occurrences. This work reports on a new discovery site of Ag-bearing tetrahedrite-(Cd) at the Kon-Dara mineral deposit (Southwestern Pamirs, Tajikistan) and summarizes the known data on rare Cd-bearing fahlores with a Cd content from 1 to 12.31 wt %. Ag-bearing tetrahedrite-(Cd) at the Kon-Dara deposit occurs as xenomorphic segregations 10–35 μm in size in association with tetrahedrite-(Fe), tetrahedrite-(Zn), galena, polybasite, and chalcopyrite, calculated which replace bournonite. According to the EPMA data, its composition averaged over seven analyses (in wt %) is as follow: Ag 16.17, Cu 25.19, Cd 10.09, Fe 0.38, Zn 0.09, Pb 0.13, Sb 25.55, As 0.18, and S 22.34. The empirical formula calculated based on 29 atoms per unit is (Cu7.40Ag2.80)Σ10.20(Cd1.68Fe0.13Zn0.03Pb0.01)Σ1.84(Sb3.92As0.04)Σ3.96S13.00. The composition of the tetrahedrite-(Cd) from Kon-Dara is similar to those from the Tyndrum Pb–Zn mineralization in Scotland, the Clara baryte–fluorite–(Ag,Cu) mine in Germany, and the Xitieshan Pb–Zn deposit in China. The formation temperature of Ag-bearing tetrahedrite-(Cd) at the Kon-Dara deposit is estimated to have been at about (170–140) ± 20°C. [ABSTRACT FROM AUTHOR]

Tellurium (Te)-bearing adularia-sericite epithermal Au-Ag deposits are widely distributed in calc-alkaline magmatic arcs and are an important current and future source of precious and critical metals. The source of ore-forming fluids in these deposits remains unclear due to the lack of in situ isotopic evidence on Au-, Ag-, and Te-bearing minerals. To advance the understanding of the source and evolution of Te and precious metals, herein, we combine in situ Pb isotope analysis with He, Ne, and Ar isotope and microthermometric analysis of fluid inclusions in ore and gangue minerals from two Te-rich and two Te-poor epithermal Au-Ag deposits that occur in an Early Cretaceous magmatic arc in the North Heilongjiang Belt, northeastern China. Ore minerals (hessite, petzite, calaverite, altaite, pyrite, chalcopyrite, and galena) from Te-rich Au-Ag deposits, including Sandaowanzi and Yongxin, have the least radiogenic Pb isotope compositions (206Pb/204Pb from 18.1 to 18.3) and the lowest μ1 values (the 238U/204Pb ratio of the lead source down to 9.14) of the deposits studied. For these Te-rich deposits, noble gas isotope data show that fluid inclusions in ore minerals contain a large proportion of mantle He (up to 25%), whereas barren early-stage minerals do not (<1%). The Pb, noble gas isotope, and fluid inclusion microthermometric results suggest that Te-rich ore-forming fluids were likely discharged from mafic magmas into convecting meteoric flow systems at shallow levels (<2 km). In contrast to the Te-rich deposits, ore minerals from the Te-poor Dong'an Au-Ag deposit have radiogenic Pb isotope compositions (206Pb/204Pb from 18.8 to 18.9) and the highest μ1 values (up to 10.54). Fluid inclusions in ore minerals contain a small proportion of mantle He (1% to 5%). The results suggest that metals and ore-forming fluids in these deposits were discharged from either more crustally contaminated intermediate-felsic magmas or leached from upper crustal rocks by convecting meteoric flow systems. Although the Te-poor Tuanjiegou Au-Ag deposit has a non-radiogenic Pb isotope composition consistent with a mafic magma source, Te is much less abundant (electrum [>95%] is the major gold- and silver-bearing mineral) than Au. The main exploration implication of these results is that unexplored volcano-plutonic centers in the northeast Xing'an Block with less radiogenic Pb isotope compositions (206Pb/204Pb < 18.3) and containing fluids with a high proportion of mantle He are more likely to generate Te-rich epithermal Au-Ag deposits than other volcano-plutonic centers in NE China. [ABSTRACT FROM AUTHOR]

Toward the super-smart society, next-generation display technologies with ultra-small size and high resolution are required. MicroLEDs are promising key technologies for next-generation full-color displays, and the external quantum efficiency in the red region should be improved. To improve red emission efficiency, we propose color-conversion red emitters combined with blue InGaN LEDs and lead-halide perovskite nanocrystals (PNCs) by using a coating process. We improved the stability of PNCs under photoexcitation by dispersing them in a methacrylate-based polymer binder, probably because of the suppressed ligand desorption and nonradiative surface recombination process. PNC films were bonded onto a blue InGaN LED to fabricate a color-conversion LED, demonstrating almost complete red conversion with higher optical performance (power density: 3.5 mW/cm2; luminance: 1.9 × 103 cd/m2) at a high current density (270 mW/cm2). This performance was achieved while maintaining the same level of external quantum efficiency (26.2%) and device lifetime (103 h) as those reported for the current PNC red LEDs. Therefore, the color-conversion LED may be a milestone in improving the device performance over the entire visible region and realizing low-cost microLED applications. [ABSTRACT FROM AUTHOR]

The formation and evolution of supermassive black holes (SMBHs) remains an open question in the field of modern cosmology. The detection of nanohertz (n-Hz) gravitational waves via pulsar timing arrays (PTAs) in the form of individual events and the stochastic gravitational wave background (SGWB) offers a promising avenue for studying SMBH evolution across cosmic time, with SGWB signal being the immediately detectable signal with the currently accessible telescope sensitivities. By connecting the galaxy properties in the large scale (Gpc scale) cosmological simulation such as MICECAT with the small scale (⁠|$\sim$| Mpc scale) galaxy simulations from ROMULUS , we show that different scenarios of galaxy–SMBH evolution with redshift leads to a frequency-dependent spatial anisotropy in the SGWB signal. The presence of slow evolution of the SMBHs in the Universe leads to a pronounced blue anisotropic spectrum of the SGWB. In contrast, if SMBHs grow faster in the Universe in lighter galaxies, the frequency-dependent spatial anisotropy exhibits a more flattened anisotropic spectrum. This additional aspect of the SGWB signal on top of the monopole SGWB signal, can give insight on how the SMBHs form in the high-redshift Universe and its interplay with the galaxy formation from future measurements. [ABSTRACT FROM AUTHOR]

Background: The effects of blue light on photosynthetic organs have been studied. However, its effects on non-photosynthetic organs, in particular, on the early stages of rice caryopsis development, are unclear. Thus, we aimed to determine the metabolic characteristics of caryopsis development under blue light to improve the metabolic quality of crop kernels. Results: We conducted a multi-omics analysis of each of the three periods from the beginning of cellular differentiation to the end of morphogenesis in post-pollination seeds of a japonica rice variety to explore the effect of blue light on metabolic levels during these metabolic changes and its genetic basis. It was found that blue light caused a gradual decrease in auxin content, a significant increase in the accumulation of JA and flavonoids, and a downregulation of the expression of many starch-related genes and proteins, leads to reduced starch synthesis and smaller starch granules. In addition, the gene co-expression network identified three transcription factors that may regulate starch and two that may regulate flavonoids. Conclusions: It was found through multi-omics testing that hormones such as jasmonic acid and auxins, and metabolites including alkaloids, flavonoids, lipids, organic acids, phenolic acids, and terpenoids altered significantly. Transcriptome and proteome analyses showed that blue light affected the seed nutrient repository activity. Specifically, starch- and gluten-related genes and proteins were significantly downregulated. Co- and WGCNA analyses identified several transcription factors that were regulated under blue light and identified key regulators of starch. Our study provides an understanding of the effects of blue light on post-flowering development in Gramineae and provides a framework for blue light-induced synthesis of secondary metabolites. Highlights: Evaluate the impact of blue light on the secondary metabolite accumulation. Confirm the accumulation of hormones and flavonoids in different blue light. Identify key candidate genes related to starch and flavonoid. Blue light leads to reduced starch synthesis and smaller starch granules. [ABSTRACT FROM AUTHOR]

Copyright of Nonferrous Metals (Mineral Processing Section) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ruwai galena ore contains a high amount of lead (Pb) and a higher silver (Ag) content than similar ores. It indicates that Ruwai galena ore has excellent potential to be utilized as a prospective source of Ag . However, recovery of Ag from the galena ore is quite challenging due to the very high iron (Fe) and zinc (Zn) content. For this reason, separating both elements from the main galena ore needs to be performed. This study examines the performance of the froth flotation process using agitation to obtain ore (or tailings) rich in Ag so that the Ag leaching process becomes more efficient. The flotation process was conducted by varying the flotation time, the concentration of KEX (potassium ethyl xanthate, as a collector), and MIBC (methyl isobutyl carbinol, as a frother). The flotation results showed that 85% Pb was successfully floated at 120 minutes, the KEX concentration of 80 ppm, and the MIBC concentration of 30 ppm. In this condition, Zn was 48%, Fe was 38% recovered, while 49% of Ag was detected.

The electrochemical interaction between galena and monoclinic pyrrhotite was investigated to examine its impact on the physical and chemical properties of the mineral micro-surface. This investigation employed techniques such as electrochemistry, metal ion stripping, X-ray photoelectron spectroscopy, and quantum chemistry. The electrochemical test results demonstrate that the galena surface in the electro-couple system exhibits a lower electrostatic potential and higher electrochemical activity compared to the monoclinic pyrrhotite surface, rendering it more susceptible to oxidation dissolution. Monoclinic pyrrhotite significantly amplifies the corrosion rate of the galena surface. Mulliken charge population calculations indicate that electrons are consistently transferred from galena to monoclinic pyrrhotite, with the number of electron transfers on the mineral surface increasing as the interaction distance decreases. The analysis of state density revealed a shift in the surface state density of galena towards lower energy levels, resulting in decreased reactivity and increased difficulty for the reagent to adsorb onto the mineral surface. Conversely, monoclinic pyrrhotite exhibited an opposite trend. The X-ray photoelectron spectroscopy (XPS) test results indicate that galvanic interaction leads to the formation of hydrophilic substances, PbSxOy and Pb(OH)2, on the surface of galena. Additionally, the surface of monoclinic pyrrhotite not only adsorbs Pb2+ but also undergoes S0 formation, thereby augmenting its hydrophobic nature.

Based on fluorescence spectrum analysis and chemical multi-element analysis, through the process mineralogy study of a refractory lead-zinc mine in Hebei, the mineral composition, structure, main mineral embedding characteristics of the ore and the occurrence state of lead-zinc were found out. The results show that the lead content in the ore is 1.07%, and the lead minerals mainly exist in galena, accounting for 85.85%. The content of zinc is 2.08%. Zinc minerals mainly exist in sphalerite, accounting for 66.06%, and zinc oxide ore accounts for 22.43%, Galena is mainly embedded in contact with sphalerite and pyrite and metasomatized sphalerite and pyrite. The contact boundary is uneven, in harbor shape, sawtooth shape, nibbling shape, etc., with strong local metasomatism. Sphalerite is mainly in irregular heteromorphic grain structure, and a small amount is embedded in vein structure, which is distributed in disseminated shape in the ore. Through analysis, the embedded particle size of lead minerals in the raw ore is too fine and the continuous relationship with zinc flash minerals is complex, resulting in high zinc content in lead concentrate, high zinc oxidation rate, high zinc content in tailings and low zinc recovery rate.

Molecules in the bulk state are typically constrained by multiple intermolecular interactions, making it challenging to develop emission‐tunable solid‐state materials. Manipulating molecular motion is essential for achieving dynamic solid‐state emissions. Herein, various emission‐tunable 4CN@polymer films are developed whose multicolor luminescence arises from different molecular motion modes within the polymer microenvironments. There are three motion modes in the films: restricted, normal, and vigorous. In the normal mode, the film emits green light, shifting to purple under UV (515–387 nm). Cooling or fuming creates a rigid environment, leading to blue emission at 426 nm. High temperatures induce vigorous motion, causing quenched emission, which can be reactivated by cooling. This mechanism underscores the significant influence of molecular motion within flexible polymers on the luminescence behavior of 4CN@polymer films, enabling multicolor emission based on environmental conditions. The wide‐range fluorescence—from purple, blue, white, green, yellow‐green to dark—indicates promising applications in multifaceted dynamic displays and information security. This study offers novel perspectives on the correlation between solid‐state molecular motion and dynamic emission. [ABSTRACT FROM AUTHOR]

Chalcopyrite and galena are primary raw materials for producing Cu and Pb metals, respectively. Flotation is still the main method to recover these two minerals. So far, lots of work has been done to recover them from low-grade refractory ores, whereas the efficient separation of these two minerals remains a major challenge. In this review, the crystal, surface, floatability and needed reagents were discussed. Firstly, the crystalline structures were introduced, including physical and chemical properties, and followed by surface properties from a density functional theory simulation perspective. As reviewed, the surface properties were closely related to their floatability, such as the degree of surface oxidization, particle size, galvanic interactions, metal ions, and so on. Moreover, the floatability of minerals could be influenced by flotation reagents, and therefore a range of new collectors and depressants were described. The review aimed to provide a deep understanding on the factors affecting Cu/Pb flotation separation as well as to develop new depressants helping to guide the flotation separation of Cu/Pb/Zn polymetallic sulfide ores for researchers. [ABSTRACT FROM AUTHOR]

A secondary copper ore in Xizang is mixed copper - lead ore, with copper primarily in the form of chalcocite and lead in the form of galena. Experimental exploration revealed that separating copper and lead in the resulting concentrate from this ore is challenging. Therefore, a flotation process prioritizing copper separation followed by lead separation was determined to be optimal. In the experimental process, inhibitors YS02 and YS04 effectively suppressed galena, while the highly selective collector BS09 yielded copper concentrates with qualified lead grades. Ultimately, under the conditions of a grinding fineness of 0.074 mm accounting for 65%, a copper separation process of once roughing and three times scavenging, and a lead separation process of once roughing, three times scavenging, and three times cleaning, the experiment achieved a copper grade of 24.63% and a copper recovery rate of 81.05% for copper concentrates, as well as a lead grade of 45.59% and a lead recovery rate of 81.32% for lead concentrates. The experimental indicators are considered ideal. [ABSTRACT FROM AUTHOR]

While lead isotopes serve to determine potential ore provenance, silver isotopes help evaluate if a specific ore flagged by Pb isotopes has actually been exploited as a silver source of bullion in antiquity. The combination of Ag and Pb isotopes thus constitutes a powerful tool to address provenance and identify potential ore sources. It has recently been observed that the vast majority of silver isotopic abundances in hundreds of silver coins from different historical periods (pre-Roman and Roman, Middle Ages, early modern times) and different localities (Persia, Greece, Rome, Western Europe, England, Spanish Americas) falls in a remarkably narrow interval (± 0.1 permil, or ± 1 on the epsilon scale used by geochemists to enhance the visibility of small isotopic differences, group 1). Five Greek coins and some pieces from Levantine hacksilber hoards dated to the Late Bronze and Early Iron Ages have isotopic abundances somewhat below the range of group 1 (–0.2 to –0.1 permil, or -2 to -1 on the epsilon scale, group 2). The coverage of Ag isotopes in ores from the western Mediterranean, with the exception of Iberia, is inexistant. Here the above-mentioned approach is illustrated with new Pb and Ag isotopic analyses of samples from southern Sardinia and southern France. The majority of Ag isotope compositions of galena samples from Sardinia belongs to group 2 and none to group 1. While scholarly works imply that Sardinia may have provided silver to the Levant during the Iron Age, the exact location of the Sardinian ores that contributed to classical and archaic Greek coins is still unknown. Galena samples from southern France (the Pyrenees, Montagne Noire, Cévennes) are characterized by Ag isotope compositions from both groups 1 and 2, indicating that silver-bearing ore deposits in Gaul could be considered a potential source for silver bullion, both before and during the Roman era. [ABSTRACT FROM AUTHOR]

Based on the study of local volumes of minerals using the classical methods of isotope dilution and thermal ionization mass spectrometry (U–Pb ID TIMS), an isotopic study of pitchblende and galena is carried out at the Natali uranium ore occurrence (Northern Transbaikalia). For the first time, it was shown that the pitchblende mineralization at the ore occurrence has a Late Silurian (422 ± 4 Ma) age. Its formation is related to the Early–Middle Paleozoic collisional tectogenesis in the area of the Tonod uplift, accompanied by increased fluid activity. The Pb isotopic composition analysis in galena associated with pitchblende show that galena is enriched in radiogenic isotopes 206Pb and 207Pb, a source of which was ancient (Precambrian) concentrations of uranium. [ABSTRACT FROM AUTHOR]

The Bou Dahar Pb-Zn district, located in the Moroccan High Atlas, is a typical carbonate-hosted Pb-Zn ore district (>30 Mt at 4 wt.% Pb, 4 wt.% Zn). In situ trace element analysis was performed using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) on galena and cerussite from different ore types. The galena is generally enriched in Ag and Sb, secondarily enriched in Cu, with a trace amount of Cd and As, but extremely depleted in Bi and Tl. The main substitution mechanism in galena is (Ag, Cu)+ + Sb3+ ↔ 2Pb2+, and at high Sb concentrations, the further substitution of 2Sb3+ + □ ↔ 3Pb2+ (where □ represents a vacancy) took place. Micro-inclusions of Cu-Sb-bearing minerals (such as tetrahedrite) and Ag-bearing minerals (such as acanthite) may exist in some situations. The features of trace elements in galena show the existence of different coupled substitutions in vein-related ore, breccia-related ore, and strata-bound ore. This suggests that the Bou Dahar district experienced multistage mineralization. The MVT model alone cannot fully explain the ore-forming process. The cerussite replacing strata-bound galena is enriched in Sr, Ba, Ag, and Cu, with minor Sb, As, and Tl. Strontium and Ba are directly substituted with Pb in the cerussite lattice. Copper and Ag are likely present in cerussite as nano-inclusions, which differs from the coupled substitution mechanism of the original galena. High concentrations of Ag may occur due to minor electrum inclusions. The enrichment of Ag, Cu, and Au in cerussite during the oxidation process may guide the optimization of ore processing, especially in extracting valuable trace/minor elements. [ABSTRACT FROM AUTHOR]

Due to the increasing demand for lead metal, the recovery of fine-grained galena resources is also constantly strengthening. High intensity conditioning (HIC) has been promoted as an efficient technology for enhancing the flotation of fine minerals. In this study, the effect of the HIC process with a multi-bladed impeller on the flotation of fine-grained galena was investigated at different agitation times and speeds. By analysis of flow field characteristics, adsorption experiments, and particle aggregation observation, the correlation mechanism of HIC affecting the flotation of fine-grained galena was revealed. Compared to the results without the HIC, the flotation recovery was 95.38% when the agitation speed was 2000 rpm and the agitation time was 5 min. Mechanistic studies showed that obtaining an appropriate slurry flow rate with external energy input not only benefited the dispersion of galena particles and reagents, but also enhanced their adsorption. The appropriate impeller shear stress can increase the flow rate difference of the slurry, making it easier for fine-grained galena to form clusters with appropriate particle size, compact structure, and small porosity, which promoted mineral flotation. This study will provide a basis for adjusting the floatability of fine sulfide mineral flotation from mixing operations. [ABSTRACT FROM AUTHOR]

The mineral purification process is a critical step in obtaining high-purity metals. The purification process for galena ore mined from Ruwai, Central Kalimantan, Indonesia, has never been studied. In this research, the flotation process was done in a flotation column with KEX and MIBC used as a collector and a frother. The results showed that the optimum flotation time was obtained at 120 min with a Pb recovery of 79.7%; while, the selectivity for Zn and Fe was 0.56 and 1.35, respectively. Upon varying KEX concentration at the optimum time of 120 min, the highest Pb recovery was obtained at a concentration of 20 ppm KEX with the selectivity of Pb with Zn and Fe were 1.02 and 1.54. By varying the MIBC concentration, the highest Pb recovery was obtained at 300 ppm MIBC concentration, with the selectivity of Pb toward Zn and Fe was 0.97 and 1.86, respectively. [ABSTRACT FROM AUTHOR]

This study evaluated the photoactivation of hydrogen peroxide gels at different concentrations using blue or violet LED in terms of whitening efficacy and tooth sensitivity. Forty patients were randomly divided into 4 groups: HP6V (violet LED and 6% hydrogen peroxide), HP6B (blue LED and 6% hydrogen peroxide), HP35V (violet LED and 35% hydrogen peroxide), and HP35B (blue LED and 35% hydrogen peroxide). The L*, a* and b* values were measured before, 1 week and 3 months after treatment, and the ΔE and ΔWID values were calculated. Tooth sensitivity was measured using a visual analogue scale (VAS) before, immediately after, and 24 h after bleaching. The ΔE, ΔWID and bleaching sensitivity values were subjected to the ANOVA test and Bonferroni post-test. HP35V and HP35B showed higher whitening efficacy than HP6VL, while HP6V did not show statistical differences compared to the other groups. Regarding bleaching-related sensitivity, the HP6V and HP6B groups presented the lowest values when compared to HP35V and HP35B. HP6V showed whitening efficacy comparable to HP35V and HP35B but with reduced tooth sensitivity. Trial registration number: NCT06165458; registration date: 12/09/2023. [ABSTRACT FROM AUTHOR]

【Objective】Caladium bicolor is a foliage plant in the Araceae family, characterized by rich colors and diverse patterns on its leaves, making it widely used for indoor and outdoor ornamental purposes and possessing good economic value. C. bicolor is often cultivated in greenhouses without additional lighting measures, which limits the quality and efficiency of seedling production due to weather conditions, making it difficult to guarantee the production efficiency and standardization of commercial seedlings. Light is an important factor in the growth and pigment accumulation of C. bicolor. The study aims to explore suitable types of light quality for tissue-cultured C. bicolor seedlings, providing a theoretical basis for improving the production efficiency and seedling quality of C. bicolor plants.【Method】We used white fluorescent light as a control and employed 7 different light quality types including LED white light, LED red light, LED blue light, LED red-blue-white 1:1:1, LED red-blue-green 1:1:1 and LED red-blue-white-green 1:1:1:1 light to treat tissue-cultured regenerated plants of C. bicolor. Various growth indicators such as leaf size, leaf thickness, plant height, number of roots, and pigment content of C. bicolor after different light quality treatments were measured to evaluate and select effective light qualities that could enhance the quality of commercial C. bicolor seedlings.【Result】Compared to fluorescent light, LED red light treatment was detrimental to the increase in the number of leaves and the thickness of petioles in C. bicolor, which were 5.3 pieces and 3.42 mm, respectively; it hindered the accumulation of total chlorophyll content and relative anthocyanin content on the leaf surface, which were 2.0 mg/g and 1.0 U/g respectively; and it was also unfavorable for the maximum photochemical efficiency of PSII (Fv/Fm) and the actual quantum yield of photosystem II〔Y(II)〕, with values of only 0.64 and 0.60, respectively. LED blue light treatment promoted the increase in plant height, petiole thickness and accumulation of relative anthocyanin content in C. bicolor, which were 21 cm, 4.6 mm and 6.1 U/g, respectively. However, it was not beneficial for the increase in the number of roots in C. bicolor. For the light combination treatment, LED red blue white green 1:1:1:1 was beneficial for the increase of leaf area, reaching 98.8 cm² . The relative anthocyanin content on the leaf surface was highest under this treatment, reaching 8.23 U/g. LED red blue green 1:1:1 treatment was not conducive to increasing plant height, petiole thickness and leaf thickness, which were 10.6 cm, 3.9 mm, and 0.70 mm, respectively. The relative anthocyanin content on the petioles of C. bicolor under LED red blue white 1:1:1, LED red blue green 1:1:1, and LED red blue white green 1:1:1:1 treatments was significantly lower than that under white fluorescent lamp light treatment.【Conclusion】Different light qualities influence the growth and pigment accumulation of regenerated plants of C. bicolor. LED blue light treatment is the most effective in increasing plant height, petiole thickness and relative anthocyanin content in C. bicolor. LED red blue white green 1:1:1:1 treatment is the most effective in increasing leaf area and relative anthocyanin content on the leaf surface. By selecting the appropriate light quality ratio based on actual conditions in production, the efficiency of standardized production of C. bicolor seedlings can be effectively improved [ABSTRACT FROM AUTHOR]

To address the issues of significant SO3, generation during pyrometallurgical copper smelting, which causes severe equipment corrosion and affects the quality of the final product, a method utilizing sphalerite and galena for SO3, con- centration control in pyrometallurgical copper smelting is proposed. Based on a thorough analysis of the tempera-ture and components affecting SO3, formation, this method primarily involves spraying and blowing sphalerite and galena into the boiler flue to reduce oxygen concentration, thereby controlling SO3, levels in the flue gas. Experimental results indicate that, compared to the original SO3, concentration of 0.5%, the addition of sphalerite and galena reduced the overall SO3, concentration to below 0.01% in the tests. The copper grade ranged between 99.9% and 100%, whereas cop- per grades obtained without any oxygen-consuming agents ranged from 99.4% to 99.6%. Therefore, this method has significant positive implications for controlling the quality of pyrometallurgical copper smelting products. [ABSTRACT FROM AUTHOR]

The peculiar behavior of arsenoplatin-1, ([Pt(µ-NHC(CH3)O)2ClAs(OH)2], AP-1), in aqueous solution and the progressive appearance of a characteristic and intense blue color led us to carry out a more extensive investigation to determine the nature of this elusive chemical species, which we named "AsPt blue". A multi-technique approach was therefore implemented to describe the processes involved in the formation of AsPt blue, and some characteristic features of this intriguing species were revealed. [ABSTRACT FROM AUTHOR]

Copyright of Multipurpose Utilization of Mineral Resources / Kuangchan Zonghe Liyong is the property of Multipurpose Utilization of Mineral Resources Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, dead Bacillus niacini microorganisms were used to support the immobilization of magnetic iron nanoparticles, creating a magnetic nano-biosorbent for wastewater treatment through magnetic separation. Magnetic nano-biosorbent was characterized via scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectrophotometry, Brunauer–Emmett–Teller analysis, and vibration sample magnetometry techniques. The laser particle sizer confirmed a uniform distribution in the particle agglomerate sizes of magnetic iron nanoparticles and magnetic nano-biosorbent, affirming successful composite formation. Energy-dispersive X-ray spectroscopy confirmed Bacillus niacini specific elements, and Fourier transform infrared spectrophotometry indicated effective Bacillus niacini coating onto magnetic iron nanoparticles. Magnetic nano-biosorbent's efficacy for toluidine blue and lead (II) removal, considering pH, contact time, magnetic nano-biosorbent dosage, and initial pollutant concentrations, was assessed. Langmuir isotherms described toluidine blue and lead (II) biosorption optimally. Kinetic data matched the pseudo-first-order and pseudo-second-order models, implying multiple biosorption mechanisms. Magnetic nano-biosorbent displayed a biosorption capacity of 66.52 ± 0.68 mg/g for lead (II) and 82.88 ± 0.79 mg/g for toluidine blue. Reusability tests showed effective reuse for up to five cycles. The magnetic nano-biosorbent presents significant potential for wastewater treatment due to its high biosorption capacity, efficient removal, and cost-effective synthesis. [ABSTRACT FROM AUTHOR]

Ag-Pb-Cu mixed concentrate is a product ofcopper and lead floating and contains a silver grade of 4208.0 g/t, along with 3.3% of copper and 43.28% of lead. And 98.80% of silver is deposited in galena. The surface of the concentrate has been heavily contaminated with the flotation reagents, leading to a little difference in the floatability between galena and chalcopyrite. Consequently, separating chalcopyrite from galena is very difficult. In this experimental study, a combined process of removing the flotation reagents by activated carbon and flotating copper by the suppression of lead was adopted to treat the concentrate. By using a high-efficiency galena inhibitor (GYC) and chalcopyrite collector (SAC), an effective recovery of silver, lead and copper from the mixed concentrates was achieved. After the treatment of the mixed concentrate, the silver grade in obtained silver-lead concentrate was 4839.2 g/t with a recovery rate of 97.36% and the grade of lead was 50.05% with a recovery rate is 97.90%. In obtained copper concentrate, the silver grade was 724.6 g/t with a recovery rate of 2.64% and the copper grade was 20.16% with a recovery rate of 91.23%. [ABSTRACT FROM AUTHOR]

Mining in northern Canada has been known to cause major environmental problems; however, historical monitoring data are scarce or non-existent. Here, we use a multi-proxy (metals, bioindicators, pigments) paleolimnological approach to track the impacts of mining activity near Keno City, on the traditional land of the First Nation of Na-Cho Nyäk Dun, in central Yukon (Canada). Silver was discovered in the early 1900s, primarily on or between two hills (Galena Hill and Keno Hill). Intensive mining has taken place ever since, with brief hiatuses dependent on ore prices and ownership of the claims. Christal Lake, a shallow site located in the valley between both hills, lies near many historical and current mines, and was once the site of a processing mill. Geochemical data show elevated background concentrations of many metals and faithfully track known mining activity. Interestingly, background (pre-mining) sediment concentrations of arsenic, cadmium, and zinc were all elevated above the Canadian Sediment Quality Guidelines for the Protection of Aquatic Life, reflecting the natural weathering of elements in high concentrations from the local catchment. These, and other metal(loid)s, increased and peaked in sedimentary concentration after ca. 1920s, when intensive mining began. Sedimentary chlorophyll-a concentrations declined with the rise of metal concentrations, although values increased again slightly in more recent sediments, perhaps reflecting the decline in recent metal inputs and reclamation of historic mine sites. Meanwhile, subfossil diatom assemblages were dominated by small benthic Fragilaria sensu lato taxa, whose assemblage composition only changed subtly with mining (similar to other shallow, non-acidified sites in the highly metal-impacted area of Norilsk, Siberia). There was no biological evidence of acidification, likely due to the neutralizing effect of the carbonate-rich catchment. Cladoceran subfossils were only present in very low numbers throughout the core, reflecting both the shallow nature and high background metal concentrations in the lake. Collectively, these data show the long-term impacts of silver mining in this subarctic environment. [ABSTRACT FROM AUTHOR]

The effect of adding orders of inorganic regulators such as zinc sulfate, copper sulfate, sodium sulfite and sodium sulfide on the flotation of chalcopyrite, galena, and sphalerite was studied under the Z-200 collector system. The results of microflotation tests showed that compared with adding inorganic regulator before the Z-200, when the inorganic regulator was added after the Z-200, there were differences in the effect on the flotation of the three kinds of sulfide minerals: the depressing effect of zinc sulfate on chalcopyrite, especially galena, was significantly weakened, and the depressing effect of zinc sulfate on sphalerite was weakened at lower dosage, but stronger at higher dosage. Copper sulfate slightly enhanced the depressing effect on chalcopyrite, had a strong activation effect on galena, especially at lower dosage, the activation effect of copper sulfate on sphalerite was significantly enhanced at lower dosage, and was weakened at higher dosage. Sodium sulfite weakened its depressing effect on chalcopyrite, especially galena, and enhanced the depressing effect on sphalerite. Sodium sulfide weakened its depressing effect on chalcopyrite, had a similar activation effect on galena at lower dosage, while its depressing effect was enhanced at higher dosage, and enhanced its depressing effect on sphalerite at low dosage. The research results can provide reference for the selection and the adding sequence of inorganic regulators in the flotation separation of sulfide ores under the Z-200 collector system. [ABSTRACT FROM AUTHOR]

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In Earth and planetary science, Pb isotopic composition is well known to play a key role in deciphering the origin and evolution of materials because they provide unique chronological and/or indigenous regional information as a radiogenic daughter nuclide from U and Th. To determine such an isotopic composition, mass spectrometers have been widely used over several decades, which requires a destructive/consuming treatment such as sputtering, laser ablation and thermal ionization. Here, we first report the non-destructive Pb isotopic measurement of natural galena (PbS) using the energy shift of muon-induced characteristic X-rays. The observed Pb isotopic composition of the natural galena is in good agreement with that obtained by conventional mass spectrometry. Such a muon-based Pb isotopic analysis method is expected to be applied to identify the production area of archaeological artefacts (e.g. bronze products), where non-destructive analysis is highly desirable compared to conventional mass spectrometry. [ABSTRACT FROM AUTHOR]

The Baiyun gold deposit is a medium-sized deposit in northeastern Hubei around the southern margin of the Tongbai-Dabie metallogenic belt. However, its genesis has not been determined. The metallogenic process of the Baiyun gold deposit can be divided into three stages: quartz + feldspar, quartz + native gold + electrum + polymetallic sulfides, and quartz + pyrite + calcite + iron dolomite + illite. In this study, LA-ICP-MS was used for in situ trace element and isotope analyses in the main and late ore stage hydrothermal sulfides to evaluate the genesis and evolution of ore-forming fluids. Gold is positively correlated with Ag, Cu, Pb, Zn, and Te and the Co/Ni ratio is greater than 1. The S isotope values of Py1 and Py2 are −0.23–3.04‰ and 1.27–6.09‰, respectively. As mineralization progressed, S isotope values increased. In situ S isotope values of the two types of galena symbiotic with pyrite in the main metallogenic stage are 2.97–3.47‰. In situ Fe isotopic values of pyrite are −0.05–0.82‰; values in the two stages are similar without significant fractionation. We inferred that the Baiyun gold deposit formed via magmatic mineralization related to the subduction of the Pacific Plate during the Yanshanian. [ABSTRACT FROM AUTHOR]

This study works on the spontaneous recombination mechanisms of GaN-based laser diodes (LDs) under low injection current by examining their power–current (P–I) curves and electroluminescence spectra. Our investigation focuses on the behavior of differential efficiency in LDs under low injection current, revealing that a competition between impurity-related yellow emissions and band-edge blue emissions leads to a change in total luminescence efficiency. Using both experimental and simulating methods, the yellow emission peak is primarily attributed to carrier recombination in deep-level defects located on the LD's p-side. A detailed explanation to the differential efficiency changing mechanism is beneficial to improve the GaN-based LD performance in future fabrication. [ABSTRACT FROM AUTHOR]

Water contamination caused by inconsistencies in the removal of contemporary colors and heavy metals constitutes a serious global ecological concern. This study introduces a composite material made of cellulose acetate coated with activated carbon, which is made more effective by including pectic enzymes. This composite is easily manufactured and has caused considerable interest due to its potential in wastewater treatment via absorption‐based techniques for the photocatalytic degradation of methylene blue dye and lead removal. Thermal processing and electrospinning are used in the synthesis process. Field emission scanning electron microscopy (FE‐SEM), Energy Dispersive Xray‐ Analysis (EDX), Brunauer–Emmett–Teller (BET), and UV‐absorbency were used to characterize the resultant pectic cellulose/activated carbon nanofibers (P‐CNFs). In addition, inductively coupled plasma‐mass spectroscopy (ICP‐MS) was used to evaluate lead ion adsorption. Several parameters, including initial lead ion and methylene blue concentrations, solution pH, and nanofiber, were investigated. Fifty percent of pectic‐containing composite (cellulose/activated carbon) P‐CNF has shown remarkable differences when compared to non‐pectic and different ratio composite due to higher surface area and porosity. It also increases light absorption and decreases charge recombination, resulting in a maximum degradation efficiency of 98.5% in a neutral solution under UV‐light irradiation for 25 min, compared to pure CNF (degradation efficiency is 49% after 60 min of irradiation). In the case of lead removal, 80% efficiency was achieved in 5 min. [ABSTRACT FROM AUTHOR]

Heavy metal ions and dyes in wastewater pose a severe hazard to ecological system and human health. This study used sulfamic acid (SA) to modify cellulose for adsorbent material preparation. The results from the structural characterization indicated that cellulose was successfully modified by introducing sulfonic acid groups to obtain sulfamic acid modified cellulose (SAMC). Subsequently, SAMC was prepared into spheres via being dissolved in ionic liquid and obtaining in antisolvent. The adsorption performance of SAMC aerogel spheres was investigated using methylene blue (MB) and lead ions (Pb2+). The maximum absorption capacity of SAMC aerogel spheres to MB and Pb2+ achieved 14.53 mg/g and 112.15 mg/g, respectively. The adsorption process conformed to the pseudo-second-order (PSO) model and Langmuir model. The adsorption mainly involved chemical action via coordination interaction between -SO32− and MB/Pb2+. Thermodynamic experiments confirmed that the adsorption process in the experiment was a spontaneous endothermic process. Therefore, this study provided a simple adsorbent production method for wastewater treatment. [ABSTRACT FROM AUTHOR]

Genthelvite from pegmatite veins hosted by the albite-enriched granite (ca.1.8 Ga) corresponding to the Sn–Nb–Ta (F, REE, Li, Zr, U, Th) Madeira deposit, Amazonas, Brazil was studied. Genthelvite, the exclusive Be-bearing mineral within the deposit, occurs as massive crystals of up to 4.7 cm in size. Compositions are homogeneous within individual crystals, although there is moderate variation in the overall composition reflecting relatively limited substitutions within the helvine–genthelvite–danalite solid-solution series, with relatively high Zn contents (36.96 to 49.45 wt.% ZnO), lower Mn contents (0.61 to 3.03 wt.% MnO), and variable Fe contents (2.10 to 10.94 wt.% FeO), completing an existing compositional gap in this system. Genthelvite formed in an alkaline and subaluminous environment, under stable conditions within the late-evolved fluids, at relatively high temperature (>400°C), in a reducing environment. The extremely high concentration of fluorine in the magma and the crystallisation of magmatic galena resulted in an effective reduction of H2S fugacity. This resulted in the stabilisation of genthelvite during the transition from the late magmatic to early hydrothermal stages of the albite-enriched granite evolution. The variability in Fe content within genthelvite is associated primarily with localised variations in the mineral assemblage (e.g. the presence of riebeckite and polylithionite). Genthelvite was altered by low-temperature aqueous fluids rich in F which resulted in the incorporation of Fe, Mn, Mg, Pb, Ba, Na, K, U and REE into the Zn2+ structural site and the allocation of excess Si, Al, Ti and P in the IVSi and IVBe structural sites. The substantial content of U and REE substituting for Zn, together with Si substituting for Be, is charge balanced by the presence of vacancies at the A site. [ABSTRACT FROM AUTHOR]

Galena is a natural mineral enriched with lead sulfide (PbS). It typically forms in hydrothermal veins associated with igneous rocks and can also occur as a gangue mineral in other ore deposits. PbS is of special importance for scientific research applications due to the possibility of tuning its semiconductor energy gap using nanotechnology in conjunction with powder metallurgy as an easy, controllable production route. In this paper, almost pure PbS was successfully produced starting from a high ratio of PbS phase galena ore. As-received galena lumps were roughly pulverized and milled to produce four particle size ranges of 38, 63, 125, and 250 µm prior to compaction and sintering in a vacuum (pre-flushed with argon gas). SEM coupled with the EDAX analysis unit was employed to investigate the microstructure and chemical composition of the as-received galena and the subsequent products after sintering. The chemical analysis confirmed the high ratio of PbS compound in the as-received galena and sintered products with approximately 85% Pb and 13% S mass ratio. The sintering process of the galena powder was carried out at different values of temperature, time, and compaction pressure. Additionally, the effect of length to diameter ratio of compacted and sintered samples was investigated. XRD analysis confirmed the existence of the PbS phase in the as-received and sintered samples at 700 °C with approximately 98 wt.%, as well as a new phase that is formed at 800 °C with a lower percentage. The micro-hardness of the as-received and sintered samples was measured and compared with the as-received galena ore. The results showed a significant reduction in the hardness of sintered galena powder compared with the bulk as-received galena by 52%. Furthermore, a relative sintered density of 99.3% for the as-received galena density signifies a novel result using powder metallurgy techniques. [ABSTRACT FROM AUTHOR]

With its quality, intensity, and photoperiod, light is a decisive abiotic factor that directly influences plant biomass and the accumulation of specialized metabolites (SMs). Photosynthetically active radiation (PAR) has significant effects on primary and secondary plant metabolism and thus influences the morphological characteristics of plants and their antioxidant systems. The aim of this study was to investigate the effects of blue, red, and a 50:50 combination of blue and red LED lighting on the SM content in broccoli, mustard, and garden cress microgreens grown in an indoor farm using the zero-acreage farming technique (ZFarming). This research aims to provide valuable insights into the optimization of light spectra to improve the nutritional quality of microgreens, with a focus on sustainable and space-saving cultivation methods. After eight days, the samples were cut in the cotyledon phenophase and analyzed in a fresh state. The microgreens grown under the blue spectrum LED lighting had the highest content of ascorbic acid (112.70 mg·100 g fw−1), total phenolics (412.39 mg GAE·100 g fw−1), and the highest antioxidant capacity (2443.62 µmol TE·L−1). The results show that the highest content of SMs in all the studied microgreens species was accumulated under the blue spectrum LED lighting. This study underlines the favorable influence of the blue spectrum (400–500 nm) on the nutrient content, especially the enhancement of SMs, in the microgreens investigated. Furthermore, the use of supplemental LED lighting proves to be a sustainable and effective means of producing microgreens with superior nutritional properties through the innovative practice of the zero-acreage farming technique. [ABSTRACT FROM AUTHOR]

Sulphur plays a fundamental role in the biological processes of chemolithotrophic microorganisms. Due to the redox characteristics of sulphur, microorganisms use it for metabolic processes. Such is the case of the dissimilatory processes in the anaerobic respiration of reducing microorganisms. The production of electrical energy from the metabolism of native microorganisms using sulphur as substrate from inorganic mineral sources in the form of Galena (PbS) was achieved using MR mineral medium with 15% (w/v) of PbS mineral concentrate. At 400 h of growth, the highest voltage produced in an experimental unit under anaerobic conditions was 644 mV. The inoculum was composed of microorganisms with spiral morphology, and at the final stages of energy production, the only microorganism identified was Bacillus clausii. This microorganism has not been reported in bioelectrochemical systems, but it has been reported to be present in corrosive environments and reducing anoxic environments. [ABSTRACT FROM AUTHOR]

The separation and recovery of valuable metals from the Huayangchuan uranium polymetallic ore was investigated based on mineralogical research and mineral processing experiments. The most promising valuable elements in the ore, according to mineralogical studies, are U, Nb, and Pb. 95.75% of U and 93.00% of Nb are found in betafite, 46.85% of Pb is present in galena, 52.01% of Pb occurs in cerussite, and associated Ag exists primarily in galena. The beneficiation process involving gravity concentration, magnetic separation, and flotation was determined based on the mineralogical characteristics of the ore. The U-Nb concentrate with U grade of 3578 ppm and recovery of 83.18 %, Nb2O5 grade of 4391 ppm and recovery of 74.55 % can be obtained, and five elements including U, Nb, Pb, Ag, and Fe are recovered. Compared with the previous beneficiation experimental process, the flowsheet is greatly simplified and the beneficiation recovery efficiency has been improved. The results of this investigation can help to address the gaps in the processing of low-grade uranium deposits with similar mineralogical properties. [ABSTRACT FROM AUTHOR]

Abstract The flotation mechanism of galena with xanthate as the collector is generally explained based on the mixed potential of the pulp, in which an anodic electron transfer reaction from the collector to the mineral is combined with an O2 cathodic reduction. Sodium sulphide, often used as a mineral activator, strongly influences the pulp's mixed potential, and depending on the dosage applied, it can become a galena depressor reagent. In this way, the current study assesses galena flotability in the absence of collector, as well as in the presence of the collector potassium amyl xanthate (PAX) and sodium sulphide. The effect of an extremely cathodic potential was also studied through the addition of hydrogen peroxide. In addition, the effect of different stages in the oxidation of the galena surface on the flotability was investigated. Moreover, the zeta potential was measured and contact angle (wettability) tests were carried out. The contact angle measurements were taken for a distilled water, PAX solution and for a mixture of PAX and sodium sulphide solution on the oxidized and non-oxidized surface of galena. All the results showed that galena could be floated in all the PAX concentrations tested. It was observed that a moderate oxidation in the galena surface may contribute to an improvement of its flotation with PAX. However, extremely anodic and cathodic potentials cause flotability close to zero. The zeta potential results showed that sodium sulphide affected the interaction between PAX and galena. The measurements of the contact angle corroborated the results obtained in the microflotation tests.

The article describes the studies on the material constitution of two lead–zinc ore samples from the Gorevka deposit. The samples are difficult ore because of fine dissemination of galena and its complex intergrowth with sphalerite; feature partial replacement of lead sulfide by anglesite and cerussite; contain colloform galena. The initial ore samples underwent the X-ray phase, chemical and grain-size analyses, with sizing of target elements. The tests of selective flotation of the samples, with variation of size grade in the lead circuit, in different reagent regimes and with the subsequent electron microscopy of the products proved the processing difficulty of the test ore. [ABSTRACT FROM AUTHOR]

The efficient separation of chalcopyrite (CuFeS2) and galena (PbS) is essential for optimal resource utilization. However, finding a selective depressant that is environmentally friendly and cost effective remains a challenge. Through various techniques, such as microflotation tests, Fourier transform infrared spectroscopy, scanning electron microscopy (SEM) observation, X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy measurements, this study explored the use of ferric ions (Fe3+) as a selective depressant for galena. The results of flotation tests revealed the impressive selective inhibition capabilities of Fe3+ when used alone. Surface analysis showed that Fe3+ significantly reduced the adsorption of isopropyl ethyl thionocarbamate (IPETC) on the galena surface while having a minimal impact on chalcopyrite. Further analysis using SEM, XPS, and Raman spectra revealed that Fe3+ can oxidize lead sulfide to form compact lead sulfate nanoparticles on the galena surface, effectively depressing IPETC adsorption and increasing surface hydrophilicity. These findings provide a promising solution for the efficient and environmentally responsible separation of chalcopyrite and galena. [ABSTRACT FROM AUTHOR]

The flotation mechanism of galena with xanthate as the collector is generally explained based on the mixed potential of the pulp, in which an anodic electron transfer reaction from the collector to the mineral is combined with an O2 cathodic reduction. Sodium sulphide, often used as a mineral activator, strongly influences the pulp’s mixed potential, and depending on the dosage applied, it can become a galena depressor reagent. In this way, the current study assesses galena flotability in the absence of collector, as well as in the presence of the collector potassium amyl xanthate (PAX) and sodium sulphide. The effect of an extremely cathodic potential was also studied through the addition of hydrogen peroxide. In addition, the effect of different stages in the oxidation of the galena surface on the flotability was investigated. Moreover, the zeta potential was measured and contact angle (wettability) tests were carried out. The contact angle measurements were taken for a distilled water, PAX solution and for a mixture of PAX and sodium sulphide solution on the oxidized and non-oxidized surface of galena. All the results showed that galena could be floated in all the PAX concentrations tested. It was observed that a moderate oxidation in the galena surface may contribute to an improvement of its flotation with PAX. However, extremely anodic and cathodic potentials cause flotability close to zero. The zeta potential results showed that sodium sulphide affected the interaction between PAX and galena. The measurements of the contact angle corroborated the results obtained in the microflotation tests. [ABSTRACT FROM AUTHOR]

Today, with the development of nuclear technology and radiation therapy equipment, radiation protection is important. This study aimed to design heavy concrete with high compressive strength and effective protection against neutron and gamma rays. In this study, 11 types of concrete with different mixing designs including 88 samples were made. In these samples, iron ore aggregates galena, limonite, hematite, polypropylene fibers, nanoparticles, micro-particles of silicon, and B4C powder have been used. Concrete quality coefficient, compressive strength, gamma, and neutron attenuation coefficients were measured for all samples. Also, the neutron attenuation coefficient for all samples was calculated using the Monte Carlo simulation (MCNPX) code and compared with the experimental values. The density, neutron attenuation coefficient, and compressive strength of concrete samples varied from 2.37 to 3.17 g.cm-3, from 0.0162 to 0.0306 cm².g-1, and from 48.0 to 81.3 MPa respectively. The linear gamma attenuation coefficient and gamma-ray tenth value layer (TVL) were obtained from 0.148 to 0.398 cm-1 and 15.74 to 5.85 cm respectively. These results showed that the highest neutron and gamma attenuation coefficients were obtained for concrete containing 70% galena iron ore and 20% boron carbide and the highest compressive strength belonged to sample G15 containing 15% galena iron ore and 1.8% boron carbide. G70 was the best concrete regarding the quality factor, defined as the product of multiplying the compressive strength and linear attenuation coefficients of neutron and gamma. [ABSTRACT FROM AUTHOR]

Modulation of the octahedral crystal field environment of Cr3+ is an effective approach to achieve tunable emission. Here, we prepared a series of broadband MP3O9:Cr3+ (M = Al, Ga, In) near-infrared (NIR) phosphors, and cubic AlP3O9:Cr3+ (APO-c:Cr3+) and monoclinic AlP3O9:Cr3+ (APO-m:Cr3+) phosphors were prepared by controlling the synthesis temperature. The emission wavelength was tuned from 787 nm for APO-c:Cr3+ to 894 nm for monoclinic InP3O9:Cr3+ (IPO:Cr3+) by regulating the M ion and reducing the crystal field intensity. Excitingly, the MP3O9:Cr3+ (M = Al, Ga, In) family shows excellent thermal stability; the emission intensity of APO-c:Cr3+, APO-m:Cr3+ and monoclinic GaP3O9:Cr3+ (GPO:Cr3+) can still maintain 95.6%, 86% and 86% of that at room temperature when heating to 423 K, respectively. An NIR LED device was prepared by incorporating GPO:Cr3+ and a blue light LED, demonstrating the potential application in night vision and non-destructive testing. [ABSTRACT FROM AUTHOR]

To address the issue of mediocre separation efficiency of depressants in the copper-lead separation process, this article synthesized a macromolecular organic depressant, polymaleic anhydride-ethylenediaminetetraacetic acid (PMA–EDTC), using a polycarboxylic macromolecule as the backbone and also introducing –N–(C=S)–S– as the solidophilic group and employed as a galena depressant. The structure of PMA–EDTC was characterized using Fourier transform infrared (FT-IR). The effect of PMA–EDTC on the floatability of galena and chalcopyrite was investigated through micro-flotation and Contact angle measurements. The experimental results demonstrated that PMA–EDTC exhibited selectivity inhibition towards galena rather than chalcopyrite across a wide pH range. At a dose of 8 mg/L, there was effective separation between galena and chalcopyrite with a separation coefficient of 24.17, effectively altering the floatability of galena while having little impact on the floatability of chalcopyrite. The selective inhibition behavior and adsorption mechanism of PMA–EDTC on galena and chalcopyrite were investigated using FT-IR, Zeta potential, and X-ray photoelectron spectroscopy (XPS). FT-IR and Zeta potential studies indicated that PMA–EDTC formed chemical adsorption on the surface of galena. XPS confirmed the model of chemical adsorption of PMA–EDTC on lead atoms in the galena surface. The results indicate that PMA–EDTC adsorbs on the surface of galena via its –(C=S)–S–group, forming a hydrophilic complex and achieving selective depression of lead and the cleaning flotation of copper. [ABSTRACT FROM AUTHOR]

Simple Summary: The aim of this experiment was to investigate the effects of different LED light colors on the growth performance, intestinal morphology, cecal short-chain fatty acid concentration, and microbiota in broilers. The results showed that blue and blue–green composite light would have better feeding advantages, as demonstrated by the fact that blue and blue–green composite light could improve ileal morphology and affect SCFAs concentration by changing the abundance of genus-level flora to improve growth performance. This study aimed to explore the effects of light-emitting diode (LED) light colors on growth, intestinal morphology, and cecal microbiota in broilers. A total of 360 healthy male Arbor Acres (AA) broilers with similar weights were selected and divided into four groups with six replicates in each group and 15 broilers in each replicate: LED white light (W), LED green light (G), LED blue light (B), and LED blue–green composite light (BG). The experimental period was 42 d, the light cycle of each treatment group was 23L:1D (23 h of light, one hour of darkness) from 1 to 3 d, and the light cycle from 4 to 42 d was 16L:8D; light intensity was 20 Lux. The results showed that the average daily feed intake and final weight of broilers receiving the B group were the highest in 21 d and 42 d compared with other groups. The average daily feed intake of the BG group was lower than that of the B group. In the same light color, small intestine villus height grows with age. On days 21 and 42, compared with other groups, the ileal villus height was higher, the crypt depth was lower, and the V/C ratio (villus to crypt ratio) was higher in the BG group. The combination of blue–green composite light was beneficial to increase the content of propionate, isobutyrate, butyrate, isovalerate, and valerate in the cecum of 21-day-old broilers and the content of isobutyrate in the cecum of 42-day-old broilers, and a decrease in cecal short-chain fatty acid concentrations with age. The B group and the BG group had higher abundances of Bacteroidetes at day 21 of age and lower abundances of Phascolarctobacterium at day 42. However, no cecal microbiota differences were detected by the Bonferroni-corrected test. In general, our research results showed that light color could promote the growth of broilers by affecting intestinal morphology, microbiota abundance (needs to be validated by further experiments), and cecal short-chain fatty acid concentrations. And blue and blue–green composite lights are more suitable for broiler growth. [ABSTRACT FROM AUTHOR]

Light plays a crucial role in photosynthesis, which is an essential process for plantlets produced during in vitro tissue culture practices and ex vitro acclimatization. LED lights are an appropriate technology for in vitro lighting but their effect on propagation and photosynthesis under in vitro condition is not well understood. This study aimed to investigate the impact of different light spectra on growth, photosynthetic functionality, and stomatal characteristics of micropropagated shoots of Persian walnut (cv. Chandler). Tissue-cultured walnut nodal shoots were grown under different light qualities including white, blue, red, far-red, green, combination of red and blue (70:30), combination of red and far-red (70:30), and fluorescent light as the control. Results showed that the best growth and vegetative characteristics of in vitro explants of Persian walnut were achieved under combination of red and blue light. The biggest size of stomata was detected under white and blue lights. Red light stimulated stomatal closure, while stomatal opening was induced under blue and white lights. Although the red and far-red light spectra resulted in the formation of elongated explants with more lateral shoots and anthocyanin content, they significantly reduced the photosynthetic functionality. Highest soluble carbohydrate content and maximum quantum yield of photosystem II were detected in explants grown under blue and white light spectra. In conclusion, growing walnut explants under combination of red and blue lights leads to better growth, photosynthesis functionality, and the emergence of functional stomata in in vitro explants of Persian walnuts. [ABSTRACT FROM AUTHOR]