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Waste electrical and electronic equipment (WEEE) contains various valuable metals, making it a potential secondary resource for sustainable metal usage. Pyrometallurgical smelting is an efficient technique to recycle WEEE by extracting precious metals into copper matte and removing impurities into slags. The impact of WEEE impurities such as CaO and Al2O3 on the phase compositions of the smelting products attracts great attention for industrial metal recovery. This study clarified the impact of CaO and Al2O3 on the equilibrium phase compositions of copper matte and SiO2-saturated FeOx-SiO2-Al2O3-CaO slags. The high-temperature smelting experiments were taken at a controlled p(SO2) of 0.1 atm and 1300 °C, followed by quenching and electron probe microanalysis. The results showed that the copper and sulfur in the smelting system were highly deported into copper matte, and their distribution in matte was enhanced by increasing CaO and Al2O3 concentrations introduced by WEEE. The chemical copper dissolution in slags increased with increasing matte grade but decreased by adding CaO and Al2O3. The iron was preferentially concentrated in slags, and higher matte grades improved the iron distribution in slags. The current experimental results enrich fundamental thermodynamic data and help optimize WEEE smelting operations for efficient recovery of valuable metals. [ABSTRACT FROM AUTHOR]

Lacustrine sediments are good recorders of palaeoenvironment changes and have been widely studied in recent years. The study of lacustrine sediments in Southwest China will improve our understanding of the complex environmental evolution history of Southwest China. Therefore, this paper presents a high-resolution rock magnetism study from the Pengtun drilling hole (PT2) in the Heqing Basin, Southwest China. The results show that the dominant magnetic minerals in the PT2 drill core are magnetite, maghemite and haematite. The magnetic susceptibility (χ) of the upper part of the core (0–13.5 m) is lower than that of the lower part (13.5–33.5 m). There is no maghemite in the upper sections. The minerals with high χ values have the characteristics of pseudosingle-domain (PSD), single-domain (SD), superparamagnetic (SP) and multidomain (MD) grains. The magnetic domains are widely distributed, and the particles are coarser. When χ is low, the magnetic domains of the different samples vary greatly, and the particles are finer. Combined with the magnetic and nonmagnetic characteristics of the sediment, we infer that the change in χ in the PT2 drill core is related to clastic input, water erosion, and reductive dissolution. [ABSTRACT FROM AUTHOR]

Polysaccharides are the main bioactive components in safflower. In this study, safflower polysaccharides (SPs) were extracted by ultrasonic assisted extraction, and four purified safflower polysaccharide fractions (named SSP1, SSP2, SSP3, and SSP4, respectively) were obtained. The physicochemical properties and in vitro physiological activities of the four fractions were investigated. The molecular weights (MW) of the SSPs were 38.03 kDa, 43.17 kDa, 54.49 kDa, and 76.92 kDa, respectively. Glucuronic acid, galactose acid, glucose, galactose, and arabinose were the main monosaccharides. The Fourier transform infrared spectroscopy (FT-IR) indicated that the polysaccharides had α- and β-glycosidic bonds. Nuclear magnetic resonance (NMR) analysis showed that SSP1 had 6 different types of glycosidic bonds, while SSP3 had 8 different types. SSP3 exhibited relatively higher ABTS+ scavenging activity, Fe+3-reduction activity, and antiproliferative activity. The results will offer a theoretical framework for the use of SPs in the industry of functional foods and medications. [ABSTRACT FROM AUTHOR]

Upland cotton (Gossypium hirsutum), an allotetraploid, contains At- and Dt- subgenome and most genes have multiple homologous copies, which pose a huge challenge to investigate genes' function due to the functional redundancy. Therefore, it is of great significance to establish effective techniques for the functional genomics in cotton. In this study, we tested two novel genome editing vectors and compared them with the CRISPR/Cas9 system (pRGEB32-GhU6.7) developed in our laboratory previously. In the first new vector, the sgRNA transcription unite was constructed into the replicon (LIR-Donor-SIR-Rep-LIR) of the bean yellow dwarf virus (BeYDV) and named as pBeYDV-Cas9-KO and in the second vector, the ubiquitin promoter that drives Cas9 protein was replaced with a constitutive CaMV 35S promoter and defined as pRGEB32-35S. The results from transgenic cotton calli/plants revealed that pBeYDV-Cas9-KO vector showed the highest editing efficiency of GhCLA1 in At and Dt subgenomes edited simultaneously up to 73.3% compared to the 44.6% of pRGEB32-GhU6.7 and 51.2% of pRGEB32-35S. The editing efficiency of GhCLA1 in At and Dt subgenome by pBeYDV-Cas9-KO was 85.7% and 97.2%, respectively, whereas the efficiency by pRGEB32-GhU6.7 and pRGEB32-35S vectors was 67.7%, 86.5%, 84%, and 87.2%, respectively. The editing profile of pBeYDV-Cas9-KO was mainly composed of fragment deletion, accounting for 84.0% and ranging 1–10 bp in length. The main editing sites are located at positions 11–17 upstream of PAM site. The off-target effects were not detected in all potential off-target sites. Taken together, the pBeYDV-Cas9-KO system has high editing efficiency and specificity with wide editing range than the traditional CRISPR/Cas9 system, which provides a powerful tool for cotton functional genomics research and molecular breeding. [ABSTRACT FROM AUTHOR]

Arsenic removal is a crucial issue in all copper smelters. Based on the Fangyuan 1# smelter, the effects of major elements (Cu, Fe and S) in sulfide concentrates on arsenic removal in the SKS copper smelting process were studied in this paper. The results show that Cu, Fe and S in concentrates have a significant influence on the oxygen/sulfur potential of smelting systems, and also affect the efficiency of arsenic removal. By regulating the proportion of the major elements in sulfide concentrates, the concentrate composition was changed from its original proportions (Cu 24.4%, Fe 26.8%, S 28.7%, and other 20%) to optimized proportions (Cu 19%, Fe 32%, S 29%, and other 20%). The distribution of arsenic among three phases in the original production process (gas 82.01%, slag 12.08%, matte 5.91%) was improved to obtain an optimal result (gas 94.37%, slag 3.45%, matte 2.18%). More arsenic was removed into the gas phase, and the mass fraction of arsenic in matte was reduced from 0.07% to 0.02%. The findings were applied to actual production processes in several other copper smelters, such as the Hengbang copper smelter, Yuguang smelter and Fangyuan 2# smelter. Therefore, the optimized result obtained in this work could provide direct guidance for actual production. [ABSTRACT FROM AUTHOR]

Although the regulatory function of miRNAs and their targets have been characterized in model plants, a possible underlying role in the cotton response to herbivore infestation has not been determined. To investigate this, we performed small RNA and degradome sequencing between resistant and susceptible cotton cultivar following infestation with the generalist herbivore whitefly. In total, the 260 miRNA families and 241 targets were identified. Quantitative-PCR analysis revealed that several miRNAs and their corresponding targets exhibited dynamic spatio-temporal expression patterns. Moreover, 17 miRNA precursors were generated from 29 long intergenic non-coding RNA (lincRNA) transcripts. The genome-wide analysis also led to the identification of 85 phased small interfering RNA (phasiRNA) loci. Among these, nine PHAS genes were triggered by miR167, miR390, miR482a, and two novel miRNAs, including those encoding a leucine-rich repeat (LRR) disease resistance protein, an auxin response factor (ARF) and MYB transcription factors. Through combined modeling and experimental data, we explored and expanded the miR390-tasiARF cascade during the cotton response to whitefly. Virus-induced gene silencing (VIGS) of ARF8 from miR390 target in whitefly-resistant cotton plants increased auxin and jasmonic acid (JA) accumulation, resulting in increased tolerance to whitefly infestation. These results highlight the provides a useful transcriptomic resource for plant-herbivore interaction. [ABSTRACT FROM AUTHOR]