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11.
本工作首次合成了Eu(DMBM)_2(2,2′-bipy)NO_3(DMBM=二对甲氧基苯甲酰甲烷,2,2′-bipy-2,2′-联吡啶)。通过元素分析、热谱、电导率、红外和拉曼光谱、质子核磁共振谱对所合成化合物进行了表征。在77K测定了固体配合物的激发光谱和发光光谱。光谱数据说明配合物含有两种Eu(Ⅲ)格位。配合物中三种配体在Eu(Ⅲ)周围的分布情况略有不同,显示出不同的晶体场效应。光谱数据表明,配合物中Eu(Ⅲ)格位属于非中心对称的点群C_1或C_3或C_2。 相似文献
12.
Ga?lle?Poulenat Sabine?Sentenac Zéphirin?Mouloungui'ephirin.mouloungui@ensiacet.fr" title="z 'ephirin.mouloungui@ensiacet.fr" itemprop="email" data-track="click" data-track-action="Email author" data-track-label="">Email author 《Journal of surfactants and detergents》2003,6(4):305-310
Sodium, lithium, and calcium soaps obtained by saponification of high-oleic sunflower oil were studied by Fourier-transform
infrared spectroscopy. Spectra of crude mixtures containing soap, glycerin, residual alkali, and triacylglycerols were compared
to those of pure soaps obtained from fatty acids. The infrared spectra of crude soaps showed the same characteristic bands
as pure ones. The absorption bands of asymmetric (ω2) and symmetric (ω1) stretching vibrations of the carboxylate group indicated that the metal-oxygen bonds of these soaps had an ionic character
whose strength differed from one cationic counterion to another. Once the characteristic absorption bands of the soaps were
assigned, a kinetics study of saponification was performed. Saponification by sodium, anhydrous lithium, and calcium hydroxides
was an autocatalytic reaction, characterized by an S-shaped kinetics curve, whereas saponification by aqueous lithium hydroxide
was stoichiometric. The structure of the metal-oxygen bond played a role in the kinetic mechanisms. 相似文献
13.
Yang Gao Junya Iihama Daiki Hamana Ryo Iwasaki Sawao Honda Toru Asaka Munni Kumari Tomokatsu Hayakawa Samuel Bernard Philippe Thomas Yuji Iwamoto 《International Journal of Applied Ceramic Technology》2023,20(2):768-779
A series of β-SiAlON:Eu2+ phosphors were synthesized from single-source precursors, perhydropolysilazane chemically modified with Al(OCH(CH3)2)3, AlCl3, and EuCl2. The single-source precursors were converted to β-SiAlON:Eu2+ phosphors by pyrolysis under flowing N2 or NH3 at 1000°C, followed by heat treatment at 1800°C under an N2 gas pressure at 980 kPa. By varying the molar ratio of the chemical modifiers, β-SiAlON:Eu2+ with the compositions close to the theoretical ones expressed as Si6−zAlzOz−2yN8−z+2y:yEu2+ were synthesized, where the z values and Eu2+ contents were controlled in the ranges of .44–.78 and .35–1.48 mol%, respectively. The polymer-derived β-SiAlON:Eu2+ phosphors exhibited green emission under excitation at 460 nm attributed to the 4f7–4f6(7f3)5d1 transition of dopant Eu2+. High-angle annular dark-field-scanning transmission microscopy analysis confirmed that the doped-Eu2+ existed interstitially within the channels along the c axis of host β-SiAlON. Compared with the conventional powder metallurgy route, the polymer-derived ceramic route in this study offers some advantages in the grain growth of host β-SiAlON and photoluminescence properties in terms of green emission intensity under excitation at 460 nm, and the highest intensity was achieved for the polymer-derived β-SiAlON:Eu2+ with z = .64 and .37 mol% Eu2+. 相似文献
14.
Ken‐Ichiro Ishimori Tsuyoshi Yaita Takaumi Kimura Takashi Yamada Satoshi Shinoda 《溶剂提取与离子交换》2013,31(4):489-500
The extraction equilibria of Am(III) and Eu(III) by using a tripodal ligand, tris(2‐pyridylmethyl)amine (tpa), with various lipophilic anions have been investigated. The extractability of both Am(III) and Eu(III) was increased by the combination of tpa and counteranions due to a synergistic effect. The separation factors between Am(III) and Eu(III) were also increased from 7.6 to 49 by the combination of counteranions and organic solvents. The extraction equilibria of Am(III) and Eu(III) with tpa in 1,2‐dichloroethane were determined by slope analysis. It was found that three anions and one molecule of the ligand coordinated to Am(III) and Eu(III) was extracted regardless of the anions. 相似文献
15.
溶胶-凝胶法制备的BaMgAl10O17:Eu前驱体的晶化过程 总被引:3,自引:0,他引:3
采用柠檬酸作为螯合物的溶胶-凝胶法制备了BaMgAl10O17:Eu(barium magnesium aluminate,BAM)蓝色荧光粉,并研究了,其晶化过程。通过X射线衍射、扫描电镜和荧光光谱等表征手段,研究了前驱体晶化过程的焙烧条件、结晶动力学、颗粒大小和发光性能等。BAM晶相在1100℃开始产生。温度达1200℃时,前驱体由无定型态完全转变成BAM晶相。在1120~1300℃时晶化反应的表观活化能为233kJ/mol。在室温下测得荧光粉的最大吸收峰和发射峰分别处在334nm和454nm。合成荧光粉的粒径为5μm左右,其形态和粒径取决于前驱体。 相似文献
16.
本文采用模板导向的方法,添加合适模板剂降低灼烧温度,合成橙红色荧光体。研究离子掺杂的荧光体Y2O3:Eu^3 A^m 、B^n 的荧光性质。发射光谱数据表明:杂质离子掺杂的荧光体Y2O3:Eu^3 A^m 、B^n 的荧光发射主峰与荧光体Y2O3:Eu^3 的荧光发射主峰(612nm)一致,为经典Eu^3 的^3D0-^7F2电偶极跃迁;杂质离子的引入明显地增强了Y2O3:Eu^3 的发光强度,并且有短时间余晖存在。 相似文献
17.
《透明皂》透明度的测定 总被引:1,自引:0,他引:1
透明度是透明皂的重要指标之一。新修订的《透明皂》标准,通过在白度计上测定透明度,实现了透明度的定量测定。通过对市场上现有的几十个品牌透明皂的透明度测定,显示出新标准测定方法比原标准更科学、更准确。 相似文献
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