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Tao TIAN Chao-lan ZHANG Feng ZHU Shan-xin YUAN Ying GUO Sheng-guo XUE 《中国有色金属学会会刊》2021,31(5):1484-1495
A column experiment was conducted to investigate the effect of phosphogypsum (PG) on the saline- alkalinity, and aggregate stability of bauxite residue. Results showed that: with increasing leaching time, the concentrations of saline-alkali ions decreased while the concentration increased in bauxite residue leachate; compared with CK (control group) treatment, pH, electric conductivity (EC), exchangeable sodium percentage (ESP), sodium absorption ratio (SAR), and exchangeable Na+ content of bauxite residue were reduced following PG treatment; average particle sizes in aggregates following CK and PG treatments were determined to be 155 and 193 nm, respectively. SR-μCT test results also confirmed that bauxite residue following PG treatment acquired larger aggregates and larger pore diameter. These results indicate that the PG treatment could significantly modulate the saline-alkalinity, and simultaneously enhance aggregate stability of bauxite residue, which provides a facile approach to reclaim bauxite residue disposal areas. 相似文献
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It is urgently necessary to seek more simple and effective methods to construct superhydrophobic metal surfaces to improve the corrosion resistance and antifouling performance. Herein, a facile method for fabricating superhydrophobic aluminum alloy surface is developed via boiling water treatment and stearic acid modification. It is noteworthy that no prepolishing on aluminum alloy is required and no caustic reagents and typical equipments are used during the preparation procedure. Therefore, the fabrication method is quite a simple and environment-friendly technique. Both micro- and nano-scaled binary structure forms at the resultant aluminum alloy surface while long alkyl chains are grafted onto the rough aluminum alloy surface chemically. Consequently, the resultant aluminum alloy exhibits outstanding superhydrophobicity. More importantly, the superhydrophobicity has excellent universality, diversity, stability, excellent corrosion resistance, and antifouling performance. The facile preparation, excellent superhydrophobic durability, and outstanding performance are quite in favor of the practical application. 相似文献
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Alison Willette Benjamin Fallen Hem Bhandari Carl Sams Feng Chen Virginia Sykes Chris Smallwood Kristin Bilyeu Zenglu Li Vincent Pantalone 《Journal of the American Oil Chemists' Society》2021,98(8):861-869
Soybean oil hydrogenation alters the linolenic acid molecule to prevent the oil from becoming rancid, however, health reports have indicated trans-fat caused by hydrogenation, is not generally regarded as safe. Typical soybeans contain approximately 80 g kg−1 to 120 g kg−1 linolenic acid and 240 g kg−1 of oleic acid. In an effort to accommodate the need for high-quality oil, the United Soybean Board introduced an industry standard for a high oleic acid greater than 750 g kg−1 and linolenic acid less than 30 g kg−1 oil. By combing mutations in the soybean plant at four loci, FAD2-1A and FAD2-1B, oleate desaturase genes and FAD3A and FAD3C, linoleate desaturase genes, and seed oil will not require hydrogenation to prevent oxidation and produce high-quality oil. In 2017 and 2018, a study comparing four near-isogenic lines across multiple Tennessee locations was performed to identify agronomic traits associated with mutations in FAD3A and FAD3C loci, while holding FAD2-1A and FAD2-1B constant in the mutant (high oleic) state. Soybean lines were assessed for yield and oil quality based on mutations at FAD2-1 and FAD3 loci. Variations of wild-type and mutant genotypes were compared at FAD3A and FAD3C loci. Analysis using a generalized linear mixed model in SAS 9.4, indicated no yield drag or other negative agronomic traits associated with the high oleic and low linolenic acid genotype. All four mutations of fad2-1A, fad2-1B, fad3A, and fad3C were determined as necessary to produce a soybean with the new industry standard (>750 g kg−1 oleic and <30 g kg−1 linolenic acid) in a maturity group-IV-Late cultivar for Tennessee growers. 相似文献
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针对呼吸道系统疾病与大气 PM2:5、 SO2 浓度序列的相关性特征, 应用多重分形消除趋势波动分析法
(MF-DCCA), 对张家界市永定区呼吸道系统疾病患病人数与大气 PM2:5、 SO2 浓度序列进行了研究。结果发现该地区
呼吸道系统疾病患病人数与大气 PM2:5、 SO2 浓度的相关性具有长期持续特征和多重分形特征。随后对它们相关性
多重分形特征的动力来源进行了分析, 通过随机重排和相位随机处理, 结果表明在不同时间尺度上的长期持续性影响
是其主要动力来源。进一步研究发现该地区呼吸道系统疾病与大气 PM2:5、 SO2 浓度序列的相关性在四个季节均具
有长期持续性的多重分形特征, 且夏季多重分形特征相对强于其他季节。 相似文献
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4,6-二氯嘧啶是一种重要的化工中间体.研究了反应温度、溶剂种类、催化剂种类、催化剂用量和反应物投料配比在4,6-二氯嘧啶合成过程中对反应的影响.结果 表明,在以邻硝基甲苯为溶剂,苄基三乙基氯化铵为催化剂,且催化剂用量为4,6-二羟基嘧啶质量的2%,n(4,6-二羟基嘧啶):n(三光气)=1∶0.8,反应温度为100~110℃的最佳条件下,产品收率可以达到93.4%. 相似文献