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1.
模糊正交法用于石墨炉探针原子化测定铋条件的研究 总被引:3,自引:0,他引:3
模糊正交法是通过把正交试验结果模糊化,然后用模糊数学的理论和方法来处理实验数据。与常规正交设计相比,能在同样实验工作量的情况下获得更多的信息。本文采用模糊正交法对元素Bi的测定条件进行优化,并将其同常规正交设计方差分析的结果进行了比较,并提出一个综合评价参数,对建立的分析方法进行了综合评价。 相似文献
2.
Summary PLOT columns have been prepared with kaolin as the liquid phase support. These columns show good efficiency with different stationary phases and good thermal stability with polar phases. The performance of columns is shown by the separation of various mixtures such as fatty acids, phenols and anilines which are of analytical importance. 相似文献
3.
Farhad Shirini Nader Ghaffari Khaligh Gholam Hossein Imanzadeh Parisa Ghods Ghasem-Abadi 《中国化学快报》2012,23(10):1145-1148
1,3-Dibromo-5,5-dimethylhydantoin,has been used as an efficient catalyst for the synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes in the presence of kaolin.All reactions are performed in the absence of solvent in relatively short reaction times in good to high yields. 相似文献
4.
《Arabian Journal of Chemistry》2020,13(2):4111-4125
The extreme nitrate (NO3−) species in drinking water leads to methemoglobinemia (blue baby syndrome) disease in new born toddlers whereas the excess phosphate (PO43−) and NO3− contents lead to the eutrophication (algae growth) problem of water sources. Upto date, the environmental researchers have developing the suitable adsorbent materials for providing NO3− and PO43− free water system. In present study, a low-cost alginate (Alg) assisted kaolin (KN) (AlgKN) composite beads were prepared and utilized for the removal of NO3− and PO43−. To improve the sorption capacity (SC) and stability, Zr4+ ions were coated onto AlgKN to get Zr@AlgKN composite beads which were prepared via., hydrothermal (Hydro) and in situ precipitation (In situ) methods. The hydro assisted Zr@AlgKN composite beads possess an enhanced SC than the in situ assisted adsorbents. In batch scale, the parameters responsible for the adsorption process such as contact time, co-ions, adsorbent dosage, pH, initial ions concentration and temperature were optimized. The adsorbents were characterized by XRD, FTIR, BET, EDAX and SEM analysis. The adsorption experimental data was fitted with isotherms, kinetics and thermodynamic parameters. The regeneration and field applicability study of the Zr@AlgKN composite beads were also investigated. 相似文献
5.
The self-consistent model of heat and mass transfer during convective drying of capillary porous media describing both the
first and the second periods of drying is presented in Musielak (Wydawnictwo Politechniki Poznańskiej, seria Rozprawy, nr
386 (2004a); Chem. Process Eng. 25, 393–409 (2004b)). The results of simulations of processes in steady conditions are shown (Musielak Wydawnictwo Politechniki
Poznańskiej, seria Rozprawy, nr 386 (2004a); Chem. Process Eng. 25, 393–409 (2004b)). The main aim of the present work is to compare experimental results with those from numerical simulations.
Three convective drying processes have been performed experimentally. The first and the second periods of drying are considered,
during which the humidity of air in the dryer changes due to evaporation. The first process is used to establish drying parameters,
whereafter the two remaining processes are simulated. Good agreement between experimental and simulation results is found,
both qualitative and quantitative. 相似文献
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7.
高岭土合成4A沸石晶化历程 总被引:6,自引:0,他引:6
4A沸石是广泛用于催化、污水处理、洗涤剂助剂等领域的一种人工合成沸石分子筛[1,2].采用化学合成法,沸石分子筛是在无定形凝胶和水溶液共存的体系中生成[3].以高岭土为原料,在低温水热条件下进行4A沸石的合成时,由于高岭土并不完全溶解于碱性溶液中,因而这一固液两相体系的反应过程,可能是在偏高岭土无定形的表面上完成.本文通过对合成过程液相成分的变化和固相特征分析,探索了该条件下4A沸石晶核生成及其成长历程.81999-04-19收稿,1999-06-25修回内蒙古自然科学基金资助课题(971302-2)合成原料为n(StQ):n(AI。O。)一2.06:1的… 相似文献
8.
Ecaterina Stela Dragan Ionel Adrian Dinu Marcela Mihai 《Colloids and surfaces. A, Physicochemical and engineering aspects》2009,348(1-3):282-288
The interaction between strong polycations, which possess the ammonium quaternary centers attached to an acrylic macromolecular chain derived from poly(N,N-dimethylaminoethyl methacrylate) (polycations Qx), and divalent counterions was investigated by viscometry and turbidimetry. Conformational changes of polycations were influenced by the polycation charge density, counterion nature (SO42− or S2O82−) and concentration. The morphology of the polycation layers deposited onto silicon wafers has been studied by tapping mode atomic force microscopy, a strong influence of the polycation and ammonium persulfate concentration on the surface topography being observed. The optimum flocculation concentration of polycation decreased and the flocculation window increased in the presence of S2O82−, in the destabilization of kaolin model dispersion. Removal of Congo Red from aqueous solution by the complex system formed between polycations and divalent counterions was also investigated. The behavior of polycations Qx in separation processes was compared with that of one polycation containing 95 mol% N,N-dimethyl-2-hydroxypropyleneammonium chloride units in the backbone (PCA5). 相似文献
9.
一种高活性透明液相NaY沸石导向剂的制备及性能研究 总被引:1,自引:0,他引:1
制备了一种摩尔组成为17Na2O:1Al2O3,:17SiO2:300~380H2O的透明液相导向剂.并以天然高岭土为原料,硅溶胶为补加硅源与该导向剂组成反应混合物原位水热合成高硅NaY分子筛.分析了导向剂的结构与作用机理,详细考察了导向剂老化时间、老化温度及其加入量对导向剂的活性与合成产物性能的影响.发现只有在导向剂存在时才能合成出NaY沸石.当导向剂透光率高于80%,呈现透明的溶胶状态,才是导向剂的活性期.采用XRD、IR、SEM、N2静态容量吸附法对结晶产物的晶体结构、骨架振动信息、外观形貌、比表面以及孔分布进行了表征.结果显示,该导向剂具有较好的导向活性,在老化时间为20.5 h,加入量为10%时,原位合成出了结晶度较高、无杂晶的高硅NaY分子筛.所得分子筛的硅铝比大于5.0,比表面为771 m2/g、孔径集中在0.51 nm. 相似文献
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