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1.
Yb:FAP和Yb:C_3S_2-FAP晶体光谱的温度特性和选择激发   总被引:1,自引:0,他引:1       下载免费PDF全文
报导了Yb :FAP和Yb :C3S2 _FAP晶体在不同温度下的吸收光谱和荧光光谱实验结果 ,研究发现由于电子_声子近共振耦合作用 ,Yb :FAP和Yb :C3S2 _FAP晶体均存在有明显的振动谱 ,Yb :FAP晶体的零声子线在低温下还劈裂为相差 10cm- 1 的两条线 .采用激光选择激发技术研究了Yb3 离子在FAP和C3S2 _FAP晶体中的格位特征 ,结果表明Yb3 离子在这两种基质中都只占据Ca(Ⅱ )格位 ,但由于CaF2 的挥发 ,导致了Ca(Ⅱ )格位的局部畸变 .  相似文献   
2.
Many Ligularia species have long been used as traditional folk medicine for theirantibiotic, antiphlogistic and antitussive activities1, and were found to be an importantsource of eremophilane. In the course of our search for bioactive sesquiterpenoids, w…  相似文献   
3.
La掺杂浓度对PLZT薄膜红外光学性质的影响   总被引:2,自引:0,他引:2       下载免费PDF全文
采用溶胶-凝胶法在Pt/Ti/SiO2/Si衬底上制备了不同La掺杂浓度PLZT(x/40/60)薄膜- x射线衍射分析表明制备的PLZT(x/40/60)薄膜是具有单一钙钛矿结构的多晶薄膜- 通过红外椭圆偏振光谱仪测量了波长为2-5—12-6μm范围内PLZT薄膜的椭偏光谱,采用经典色 散模型拟合获得PLZT薄膜的红外光学常数,同时也拟合获得PLZT薄膜的厚度- 随着La掺杂浓 度的增大,折射率逐渐减小- 而消光系数除PLZT(4/40/60)薄膜外,呈现逐渐增大的趋势- 分析表明这些差异主要与PLZ 关键词: PLZT薄膜 红外光学性质 红外椭圆偏振光谱  相似文献   
4.
三嗪类光学探针与标记分析   总被引:4,自引:0,他引:4  
马会民  苏美红  梁树权 《分析化学》2003,31(10):1256-1260
评述了以三聚氰氯作桥联剂或骨架而合成的三嗪类衍生物、特别是其光学标记探针的研究进展及分析应用。  相似文献   
5.
李涛  张勤远  姜中宏 《物理学报》2006,55(8):4298-4303
研究了能量接受离子Ce3+对Er3+上转换发光强度以及Er3+在1.5μm附近波段发光性能参数的影响,并从能量匹配及能级结构角度出发对Er3+/Ce3+间的能量转移机制进行了分析.分析认为,4I11/2能级的Er3+通过无辐射能量转移把能量传递给2F5/2能级的Ce3+关键词: 氟磷酸盐玻璃 光谱性质 光纤放大器 3+和Ce3+')" href="#">Er3+和Ce3+  相似文献   
6.
Some new coordination polymers of Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II), obtained from the interaction of metal acetate with dipotassium salt of N,N’-di(carboxyethylidene)terephthalaldehydediimine (K2SB) are described. The products, which have been characterized by elemental analyses, magnetic measurements, thermogravimetric analyses, electronic and infrared spectral studies, have composition, [M(SB)(H2O)2]n. These colored coordination polymers are non-hygroscopic and quite stable at room temperature. On the basis of analytical data and IR studies, a 1:1 metal to ligand stoichiometry has been suggested to these coordination polymers. The IR studies have also revealed that ligands are coordinated to metal ion through carboxy oxygen and azomethine nitrogen. All the studies suggested tetradentate nature of the ligand with octahedral symmetry of the coordination polymers. All the coordination polymers are insoluble in acetone, ethanol, chloroform, methanol, benzene, DMF and DMSO. The thermal decomposition of the coordination polymers is studied and indicates that not only the coordinated water is lost but also that the decomposition of the ligand from the coordination polymers is necessary to interpret the successive mass loss.  相似文献   
7.
In this paper,p-tricyanovinyl-N,N-dialkylanilines were synthesized as model compounds and through their spectroscopic behavior,the photo-induced electron transfer,charge separation were discussed and the aggregation in DMSO-H_2O system was investigated.  相似文献   
8.
The properties of the triplet excited state of [60] fullerene-containing cyclic sulphoxide have been investigated by time-resolved absorption spectroscopy. Transient absorption bands of [60] fullerene-containing cyclic sulphoxide showed two decay-components, which wrer attributed to triplet excited states of different spin multiplicity. The properties of photoexcited states of [60] fullerene-containing cyclic sulphoxide are also reported.  相似文献   
9.
This review covers our extensive research activities in the area of fluorine containing phospha- and arsaalkenes as well as selenocarbonyls, which differ considerably in their properties and reactivities from their alkyl and aryl counterparts and thus contribute in a gratifying manner to the still growing field of unsaturated element-carbon compounds of 3rd and 4th row main group elements E. Of particular interest is the influence of the fluorine substituents and other small groups (OR, NR2) with either inductive and/or mesomeric effects on the polarity and reactivity of the EC bond. Addition reactions of proton acidic and hydridic polar HX reactants as well as [2+2], [3+2] and [4+2] cycloadditions have been thoroughly studied. The results obtained allow a classification of the EC systems within five different types, A to E, and prove a change from “normal” to “inverse” heteroalkenes in this sequence. The ligand properties of some derivatives have also been investigated in some detail.  相似文献   
10.
The spectroscopic emission intensities from excited F atoms in SF6-O2 discharges at 1 torr have been correlated to the densities of atoms in their ground electronic state by measuring the excitation efficiencies of the electrons in the energy range 11 to 17 eV with a method which essentially consists in the analysis of the emission of Ar or N2, added as actinometer gases to the discharge mixtures. The general applicability of the method has been tested by a direct titration of F atoms with chlorine. The spectroscopic analysis has allowed the determination of useful information on the trends of both the electron densities and their energies as a function of the oxygen percent in the feed.  相似文献   
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