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Engineering,Hunan University摘 要:One-step pretreatment,anodization,is used to activate the polyacrylonitrile (PAN)-based carbon fibers instead of the routine two-step pretreatment,sensitization with SnCl2 and activation with PdCl2.The effect of the anodization pretreatment on the graphitization of PAN-based carbon fibers is investigated as a function of Ni-P......
utilization of cornstalk makes low manganese dissolution ratio. In the research, pretreatment for cornstalk was proposed to improve manganese dissolution ratio. Cornstalk was preprocessed by a heated... hydrolysis. Through acid pretreatment for cornstalk, the manganese dissolution ratio was improved from 50.14% to 83.46%. The present work demonstrates for the first time the effective acid......
分析硅偶联剂合成产生的废催化剂中铂的样品预处理研究 吴立生1,李华2,董占能1,李秋果2,谢芳琴2 (1.昆明理工大学环境科学与工程学院,云南昆明,650093;2.长江大学化学与环境工程学院,湖北荆州,434100) 摘要:有机硅偶联剂合成中产生的废催化剂,含有微量的铂和大量有机硅高聚物,铂的分离,分析难度较大.本文采用王水与氢氟酸共同溶解硅和铂的方法,达到铂分析的全溶制样目的.研究了预处理制样过程中各种因素对铂分析的影响.实验结果表明,溶解1.000 g废催化剂样品,优化的操作因素如下:氢氟酸量为5 mL,除氟用硫酸量为2 mL,溶铂用的王水量为5mL,除硝酸用的盐酸量为1 mL,定......
土壤中铅,镉测定的试样预处理方法的改进 杨启霞1,杜旭昌2,韩吉衢3 (1.烟台大学,环境与材料工程学院,烟台264005;2.莱州市锅炉检验所,莱州,261400;3.烟台大学,光电技术学院,烟台,264005) 摘要:作为对GB/T 17140-1997中所列方法的改进,建议用混合酸(VHNO3+VH2O2+VHF=4+2+1)在微波消解仪中消解试样.微波消解的参数也进行了试验并确定了最佳条件,所得试样溶液蒸发至浆状并加盐酸溶解盐类,将试样中的Pb(Ⅱ),Cd(Ⅱ)以碘化物络阴离子的形式萃取入4-甲基戊酮-2(MIBK)液层中,并在MIBK溶液中用火焰原子吸收光谱法测定铅及镉.试验结......
; natural mordenite; pretreatment; orthogonal design; methylamine; [全文内容正在添加中] ......
on heat treatment of the TC4 bars that were manufacted by VAR melting, forging, precision forging and rolling were studied. The results show that high temperature pretreatment can significantly improve the microstructure; both conventional heat treatment and high temperature pretreatment can meet the standard; the performance by high temperature pretreatment of the solution and aging can......
. The results by scanning electron microscopy (SEM) show that the coating of the sam-ple (0.09 wt pct Si) with iron-electrodeposited pretreatment eliminates the reactive zones which are found in the coating without iron-electrodeposited pretreatment. The galvanized sample (0.28 wt pct Si) with iron-electrodeposited pretreatment exhibits a compact and coherent coating. The coating of the sample (0.37 wt pct......
distributed particle size about 70 nm was successfully synthesized. The effect of microwave-assisted method as pretreatment and after-treatment on the structure and luminescent was studied property. Results indicate that the after-treatment by microwave would enhance the crystallinity as well as fluorescence intensity, the fluorescence intensity increased with the time of microwave pretreatment time......
；浸金；除铁Pretreatment by sulfuric acid-curing of calcine roasting for gold ores with high sulfur and arsenic contentsYANG Yong-bin,ZENG Guan-wu,LI Qian,LIU Xiao-liang,JIANG Tao,LIU Bo(School of Minerals Processing and Bioengineering,Central South University,Changsha 410083,China)Abstract:Based on thermodynamics between iron oxides and sulfuric acid,a pretreatment process of sulfuric acid-curing......
to sulfate. After alkaline leaching, cyanidation and adsorption were carried out for 24 h. The dissolution of gold by NaCN is increased to 95.3% from 12.8% before pretreatment, and meanwhile 99.3% of the adsorption of gold by activated charcoal. The consumption of NaCN for one ton ore is 10 kg, which is 1.2 times less than that before pretreatment. As it is carried out under normal temperature......
