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991.
研究含汞土壤的修复问题,采用热解析和低温等离子体综合技术探究新途径,调整温度、添加剂、时间等因素来判断脱汞效果并探究其不同形态,分析工艺过程废料的内部联系,并对废气处理进行分析实验。结论如下:(1)通过改良技术的BCR连续萃取法,得出研究区汞的形态主要为有机结合态(53%)。之后依次是氧化物结合态(33%)、酸可提取态(8%)、残渣态(6%)。(2)温度对热解析程度影响较大。在500℃以上的热解析条件下,土壤中的汞浓度不足1.5 mg·kg-1。(3)当选用400℃的解析温度时,40 min汞去除总体完成。在低于1 700 mg·kg-1的浓度下,汞去除率随着土壤中的含量的增大而减小。(4)氯化钙对于热解析的促进作用最强,柠檬酸、升华硫也有一定作用,硫化钠对于汞去除形成阻滞。(5)低温等离子体的最佳状态是电源设置电压为22 kV,频率为660 Hz。整个系统的汞去除程度可达近90%。 相似文献
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The dinuclear zinc complexes as high performance catalysts were used to catalyze phospha-Michael reaction of exocyclic α,β-unsaturated benzocyclic ketones under mild conditions, and the desired products possessing 1-indanones or 1-tetralones skeleton were obtained with excellent enantioselectivities of up to 99%/99% ee and yields of up to 99%. The absolute stereochemistry of the major products catalyzed by (R,R)-L1 was determined to be the (R,R)-configuration by X-ray crystallographic analysis of 3d. A positive nonlinear effect was observed and the possible mechanism was proposed. 相似文献
995.
Hui Li Zejun Jiang Xiaolin Cao Hang Su Hua Shao Fen Jin Lufei Zheng A. M. Abd El-Aty Jing Wang 《Chromatographia》2018,81(2):359-364
996.
Zi‐Yi Yu Han Lai Wen‐Juan Zhao Rui Wu Xue‐Sen Liu Li‐Hua Gan 《International journal of quantum chemistry》2017,117(19)
To elucidate the structure of a compound is a necessary step for its practical applications. To study the structure and properties of metal sulfide fullerene Sc2S@C88 detected by mass spectrometry, 11 194 isomers of C88 and 33 isomers of Sc2S@C88 were systematically examined by density functional theory calculations. The calculations show that the two lowest‐energy isomers are Sc2S@C88:81 738 (IPR‐35) and Sc2S@C88:81 735 (IPR‐32), followed by Sc2S@C88:81 729 (IPR‐26), Sc2S@C88:81 712 (IPR‐9), and Sc2S@C88:81 733 (IPR‐30). Structural analysis shows that the first two energetically favored isomers are bridged by the third and fifth energetically favored isomers, which can transfer into each other via direct Stone–Wales rotation. The calculations of temperature effect show that the first two favored isomers become dominant forms of Sc2S@C88 with decreasing temperature and may coexist in the soot. This structural convertibility among favored isomers of Sc2S@C88 suggest a hidden rule that birds of a feather flock together in metal sulfide fullerenes. This rule may decrease the range of candidate cages for the structural identification of a metal sulfide fullerene. IR spectra are simulated for helping the future experimental identification of Sc2S@C88. 相似文献
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A new capillary electrophoresis method was developed to study the synergistic effect of superoxide dismutase and jujuboside A or B on scavenging superoxide anion radical in serum matrix respectively, in which superoxide anion radical was generated from pyrogallol autoxidation. The electrophoresis conditions, and the factors affecting the productive rate of purpurogallin, such as pyrogallol autoxidation product and the activity of superoxide dismutase, were optimized. Under optimal conditions, the content of superoxide dismutase in Gibco newborn calf serum was 7.06 mg/L, RSD was 2.01% and the average recovery was 98.4%. The values of IC50 for jujuboside A and B in the serum matrix were 157.67 and 31.60 mg/L respectively, and they both had synergy on scavenging superoxide anion radical with superoxide dismutase, but there was no the dose‐dependency on this synergy. 相似文献
999.
Wang Xuedong Hua Chaolong Xu Xinwei Wei Dongzhi 《Applied biochemistry and biotechnology》2019,188(1):138-146
Applied Biochemistry and Biotechnology - In order to obtain high 4-androstene-3,17-dione (AD) yield, nucleus degradation needs to be avoided during phytosterol bioconversion process with... 相似文献
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