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31.
Novel spherical mesoporous silica materials with uniform diameters and starburst mesopore structures were synthesized by a simple one-step procedure with ethanol as the co-solvent in dilute aqueous solution and their formation mechanism was proposed. The arrangement of the pore canal and the diameter of the sphere could be tailored by altering the concentration of ethanol. 相似文献
32.
33.
TS分子筛催化性能研究Ⅰ.TS-2分子筛催化1,2-丙二醇液相氧化反应的研究①伏再辉尹笃林(湖南师范大学精细催化合成研究所,长沙410081)关键词TS-2分子筛1,2-丙二醇氧化催化氧化自1983年Taramasso[1]首次合成具有ZSM-5结构... 相似文献
34.
Summary Three -Cyclodextrin derivatives (-CDs) were synthesized by substituting the 2,6-OH groups of -CD with allyl groups and the 3-OH groups with three different acyl groups (valeryl, heptanonyl, octanoyl). The chromatographic properties of these -CDs as stationary phases for capillary gas chromatography (CGC) were studied. The test results showed that the three -CDs possessed good coating properties and that the capillary columns coated with them exhibited high column efficiency. These -CDs can separate not only the disubstituted benzene isomers but also some racemic compounds. 相似文献
35.
脱蜡剂DF-1是一种含多种有机成分的碳氢化合物,经气相色谱-红外光谱联用分析后,确定了这些组分的组成与含量。 相似文献
36.
X. H. Liu M. Sun J. J. Yue Y. X. Yin X. L. Liu F. M. Miao 《Journal of Molecular Structure》2003,620(2-3):227-230
In this paper, we carried out a theoretical study on the active site structures of the Mn-SOD with ab initio Hartree–Fock SCF method, and analyzed the molecular orbital energies, charges and atomic orbital contribution to the frontier molecular orbital. 相似文献
37.
Lei Qiao Chao Zhang Xiang‐Wen Zhang Zi‐Chuan Wang Haolin Yin Zhong‐Ming Sun 《中国化学》2020,38(3):295-304
The polypnictide complexes of rare earth cations have drawn the attention of the scientific community for their uncommon bonding modes and potential applications. Herein, we present a systematic and comprehensive summary on recent advances in the field of rare earth polypnictides, focusing on their synthesis, structures, and reactivities. The structural stabilizing effects imposed by the electropositive rare earth cations as well as the reducing capability of rare earth precursors in the synthesis of these polypnictide complexes are described in this review. We also disscuss in detail the bonding interactions and coordination modes between rare earth cations and polypnictide clusters as well as the similarities and the peculiarity of some structures. 相似文献
38.
β-甲基地高辛药物中有关物质的检测 总被引:1,自引:0,他引:1
报道了用高效液相色谱法检测β-甲基地高辛中的有关物质。色谱条件:色谱柱用SpherisorbC_(18),10μm,4.6mm×150mm,检测波长218nm,流动相:乙腈-水(34:66)。检测结果提示,目前的精制工艺需进一步改进。 相似文献
39.
The thermal decomposition characteristics of1,7-diazido-2,4,6-trinitrazaheptane (DATH) and multi-component systems containing
DATH were studied by using DSC, TG and DTG techniques. Three –NO2 groups in the DATH molecule break away first from the main chain when DATH is heated up to 200°C. Following this process,
the azido groups and the residual molecule decompose rapidly to release a great deal of heat within a short time. In the multi-component
systems, DATH undergoes a strong interaction with the binder of the double-base propellant and a weak interaction with RDX.
The burning rates of the two propellants were determined by using a Crawford bomb. The results showed that the burning rate
rises by about 19–66% when 23.5%DATH is substituted for RDX in a minimum smoke propellant. Meanwhile, the N2 level in the combustion gases is enhanced, which is valuable for a reduction of the signal level of the solid propellant.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
40.
用DSC研究纯三水铝石溶出动力学 总被引:1,自引:0,他引:1
在DSC上研究了NaOH溶液中合成三水铝石的溶出过程动力学。应用非等温反应动力学模型计算了动力学参数,分析和确定了反应机理。模型计算结果与用DSC测得的结果吻合。 相似文献