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61.
将煅烧后的电解锰渣作为单一的实验原料,采用烧结法,制备微晶玻璃,通过正交实验对锰渣微晶玻璃的热处理方案及性能进行探讨。实验通过DSC、XRD、SEM等方法对样品的性能进行表征,并测试了样品的体积密度、抗弯强度等性能。结果显示:不同的热处理条件下的锰渣微晶玻璃的主晶相均为透辉石(含铁),次晶相为普通辉石相。在800℃/0.5 h+980℃/1 h的热处理条件下得到的锰渣微晶玻璃的综合性能最优,其抗弯强度为106.82 MPa;体积密度为2.68 g/cm^3;维氏硬度为4.43 GPa;耐酸度为0.71%;耐碱度为0.07%。此外,锰渣微晶玻璃用作建筑材料,有非常大的应用潜力。 相似文献
62.
S. Karthikeyan A. Suganthi K. Bhuvaneswari J. S. Kennedy 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2019,36(2):270-277
An efficient analytical method was developed and validated using a modified QuEChERS method and LC-MS/MS for the detection and quantification of neonicotinoid insecticide residues in rice whole grain and rice straw. The samples were extracted using acetonitrile and cleaned up by dispersive solid-phase extraction. Validation based on five fortification levels showed good recoveries of neonicotinoids ranging from 75% to 116 % and 60% to 105 % for rice whole grain and straw, respectively. The precision ranged between 3% and 17 %, and 2% and 10 % for grain and straw, respectively. The limit of detection was from 0.007 to 0.0084 mg kg?1 and 0.005 to 0.15 mg kg?1 and the limit of quantification was in the range of 0.024–0.028 mg kg?1 and 0.016–0.051 mg kg?1 for rice whole grain and rice straw, respectively. Monitoring of farm gate samples indicated that, out of 24 samples, 1 rice whole grain sample was contaminated with thiamethoxam residues (0.07 mg kg?1). 相似文献
63.
This work presents the influence of dispersants on coal-water slurry (CWS), which was prepared from the solid residue of plasma pyrolysis of coal. The effects of dispersant type, solid concentration, dispersant content, and temperature on the rheological properties of CWS are examined. A suitable empirical model regarding the relation between viscosity and temperature is proposed. Through the sedimentation experiment of CWS, dispersants are found to significantly promote the stability of CWS. 相似文献
64.
Dong Sun Lin Yang Ning Liu Wenju Jiang Xia Jiang Jianjun Li Zhengyou Yang Zhengping Song 《中国化学工程学报》2020,28(3):864-870
An environmentally friendly and resource-conserving route to the clean production of electrolytic manganese was developed, in which the electrolytic manganese residue(EMR) was initially calcined for cement buffering;then the generated SO_2-containing flue gas was managed using manganese oxide ore and anolyte(MOOA) desulfurization; at last, the desulfurized slurry was introduced to the electrolytic manganese production(EMP). Results showed that 4.0 wt% coke addition reduced the sulfur of calcined EMR to 0.9%, thereby satisfying the cement-buffer requirement. Pilot-scale desulfurization showed that about 7.5 vol% of high SO_2 containing flue gas can be cleaned to less than 0.1 vol% through a five-stage countercurrent MOOA desulfurization. The desulfurized slurry had 42.44 g·L~(-) Mn~(2+) and 1.92 g·L~(-1) S_2 O_6~(2-), which was suitable for electrowinning after purification, and the purity of manganese product was 99.93%, satisfy the National Standard of China YB/T051-2015.This new integrated technology fulfilled 99.7% of sulfur reutilization from the EMR and 94.1% was effectively used to the EMP. The MOOA desulfurization linked the EMP a closed cycle without any pollutant discharge, which promoted the cleaner production of EMP industry. 相似文献
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In order to improve the thermal stability of condensed polynuclear aromatic(COPNA) resin synthesized from vacuum residue, 1,4-benzenedimethanol was added to cure COPNA resin. The curing mechanism was investigated by proton nuclear magnetic resonance spectrometry, solid carbon-13 nuclear magnetic resonance spectrometry and Fourier transform infrared spectroscopy. Microstructures of the uncured and the cured COPNA resins were studied by scanning electron microscopy and X-ray diffractometry. The thermal stability of COPNA resins before and after curing was tested by thermogravimetric analysis. The element composition of the cured COPNA resin heated at different temperatures was analyzed by an element analyzer. The results showed that the uncured COPNA resin reacted with the cross-linking agent during the curing process, and the curing mechanism was confirmed to be the electrophilic substitution reaction. Compared with the uncured COPNA resin, the cured COPNA resin had a smooth surface, well-ordered and streamlined sheet structure with more crystalline solids, better molecular arrangement and orientation. The weight loss process of the uncured and cured COPNA resins was divided into three stages. Carbon residue of the cured COPNA resin was 41.65% at 600 ℃, which was much higher than 25.02% of the uncured COPNA resin, which indicated that the cured COPNA resin had higher thermal stability. 相似文献
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