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161.
162.
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
163.
Fa Jie Yang Da Ling Yang Shou Hai Zhang Xi Gao Jian 《中国化学快报》2007,18(8):966-968
A new interfacial polymerization (IP) procedure is developed in order to synthesize polypiperazine-amide thin-film membrane on the inner surface of poly(phthalazinone ether sulfone ketone) (PPESK) hollow fiber ultrafiltration (UF) membrane.A hollow fiber composite membrane with good performance was prepared and studied by FT-IR and scanning electron microscopy. 相似文献
164.
A new fluorescent compound based on calix[4] arene skeleton was synthesized.Its complexation ability with transition metal ions,such as Fe^3 ,Co^2 ,Ni^2 ,Cu^2 ,Zn^2 and Ag^ ,Was investigated by UV-vis and fluorescent spectra. 相似文献
165.
本文续前报在恒定溶液总离子强度I=1.00mol·kg~(-1),改变葡萄糖在混合溶液中的质量百分数x=5%、15%和20%的条件下,应用电动势法测定了无液接界电池(A)和电池(B)的电动势: Pt,H_2(1.013×10~5Pa)|HCl(m),d-Glucose(x),H_2O(1-x)|AgCl-Ag (A) Pt,H_2(1.013×10~5Pa)|HCl(m_A),NaCl(m_B),d-Glucose(x),H_2O(1-x)|AgCl-Ag(B) 其中x代表葡萄糖在水中的质量百分数,m_A和m_B分别是HCl和NaCl在混合溶液中的质量摩浓度。利用电池(A)的电动势数据得到了AgCl-Ag电极在d-Glucose-H_2O混合溶液中的标准电极电势Φ_m~0,讨论了HCl的迁移性质,利用电池(B)的电动势数据,确定了HCl在HCl-NaCl-d-Glucse-H_2O体系中的活度系数γ_A,实验结果表明:在恒定总离子强度下,HCl的活度系数服从Harned规则。HCl的迁移自由能与葡萄糖的质量百分数x成线性关系。计算了HCl 相似文献
166.
Synthesis and Characterization of Novel Orange-emitting Iridium(Ⅲ) Complexes with Diphenylquinoline Ligands Containing Fluorinated Substituent 总被引:1,自引:0,他引:1
Xiao Wei ZHANG Chu Luo YANG Zhong An LI Lin Na ZHU Jin Gui QIN Jia GAO Dong Ge MA 《中国化学快报》2006,17(3):411-414
Three new cyclometalated iridium(m) complexes based on ligands of diphenylquinoline with fluorinated subsfituents were prepared, and characterized by elemental analysis (EA), ^1H NMR, and mass spectroscopy (MS). The photophysical and electrophosphorescent properties of the complexes were briefly discussed. 相似文献
167.
Synthesis, Characterization and Thermal Decomposition Mechanism of Cetyltrimethyl Ammonium Tetrathiotungstate 总被引:2,自引:0,他引:2
Gaojun An Yunqi Liu Yongming Chai Hongyan Shang Chenguang Liu 《天然气化学杂志》2006,15(2):127-133
The synthesis, characterization and thermal decomposition mechanism of cetyltrimethyl ammonium tetrathiotungstate (CTriMATT) were studied herein. The as-synthesized CTriMATT was characterized by Elemental analysis, X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Ultraviolet visible (UV-Vis) spectra. The results showed that the as-synthesized CTriMATT had high purity and good crystallinity. The introduction of alkyl groups induced a shift of the stretching vibration band of W-S bond to lower wavenumber, while it had no influence on the position of WS4^2-. Thermogravimetric analysis (TG), differential thermal analysis (DTA) and in situ XRD characterizations revealed that CTriMATT began to decompose at 423 K in nitrogen and was converted to WS2 eventually. In addition, the decomposition product of CTriMATT at 673 K in nitrogen was characterized by N2 adsorption (BET) and scanning electron microscopy (SEM). The results demonstrated that WS2 with higher specific surface area, and pore volume could be obtained from the thermal decomposition of CTriMATT in nitrogen. 相似文献
168.
Fe-Ni-B-O纳米合金的合成及其催化制氢性能的研究 总被引:2,自引:0,他引:2
Preparation and catalytic performance of Fe-Ni-B-O nano-alloy having crystal-palpus structure has been studied. Black powder was synthesized by reducing mixture solution of Fe2+, Ni2+ with KBH4 as reducing agent and polyethylene glycol as dispersant. Fe-Ni-B-O nano-alloy of crystal-palpus structure was obtained after hydrogen reduction of black powder. TEM shows that crystal-palpus length is 200~400 nm, diameter is 2~4 nm. The analytic results indicate that the total content of Fe and Ni is 86.6%, B is 5.08%. The alloy exhibits excellent catalytic performance. Hydrogen generation rate can approach 100% especially when pH is 8. 相似文献
169.
几种常见水果的微量元素分析 总被引:1,自引:0,他引:1
运用原子吸收分光光度法测定了几种常见水果中部分微量元素含量。其中榴莲的Mg、Zn、Cu、K含量位于四种水果之首。美国提子中Ca含量最高,芒果中Fe含量最高。以上差别具有统计学意义。六种元素的回收率为90%-106.5%。连续6次测定样品,变异系数(CV)为0.96%。 相似文献
170.
Organic chelating reagent influences upon the redox adsorption of activated carbon fibertowards Au3- were systematically investigated. The experimental results indicated that the presenceof organic chelating reagent on activated carbon fiber strongly affects adsorption capacity ofactivated carbon fiber towards Au3+. The reduction-adsorption amount of Au3+ increased three timesby the presence of 8-quinolinol. Furthermore, The reduction-adsorption amount of Au3+ depended onthe pH value of adsorption and temperature. 相似文献