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11.
报道了含钒(IV)和钒(V)的钨锗混合价杂多酸盐的合成、电子吸收光谱及单电子还原态的ESR谱。α-和β-[HGeV^I^VV2^VW9O40]^7^-的溶液ESR谱是由40余条超精细线组成的, 表明在阴离子中3个VO6八面体是角顶共用, 且其中一个桥氧原子是质子化的。  相似文献   
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Silks represent some of the most precious ancient and historic textile artefacts in collections worldwide.Their optimum preservation demands an appreciation of their characteristics.One important concern,especially with regard to ancient Chinese silks,is whether the fabrics have been degummed.Silks with remnant sericin gum coating the fibroin fibres would require different conservation protocol.In previous research on aged silks,the presence of sericin has been inferred from amino acid analysis of hydrolysa...  相似文献   
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三种新的铕(Ⅲ)三元配合物的合成及发光性质研究   总被引:4,自引:0,他引:4  
合成了吡嗪[2,3-f] 并邻菲罗啉及其一系列衍生物,作为第二配体,并以二苯甲酰甲烷为第一配体,合成了3种新的铕(Ⅲ)三元配合物.通过元素分析、红外光谱、核磁共振光谱确定了它们的组成,研究了三种配合物的热稳定性、成膜性能和光致发光性能(发光强度、荧光量子效率和寿命),并初步从理论上探讨含有不同基团的第二配体的结构对铕(Ⅲ)配合物发光的影响,结果表明:这三种铕(Ⅲ)三元配合物均为优良的红色发光材料,而且在真空条件下均形成均衡的薄膜,这为以这三种铕(Ⅲ)配合物作为发光层材料制作有机电致发光器件提供了认识基础.  相似文献   
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The possibility to use monocarboxylic acids and their mixtures with amines for copper concentrating by the way of micellar extraction at cloud point temperature, and later atomic absorption spectrometry (AAS) determination was investigated. Under the optimum conditions, preconcentration of 100 ml of water sample in the presence of 1% non-ionic surfactant OP-10, 0.005 M capric acid and 0.01 M octylamine permitted the detection of 0.01 μg ml−1 copper. The proposed method has been applied to the AAS determination of copper in water samples after cloud point extraction.  相似文献   
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The specificity of interphase transfer of organic reagents of different types between water and the nonionic-surfactant-rich phases at the cloud point temperature was investigated. In contrast to organic solvents, the ability of the micellar phases to extract highly charged ions of organic reagents was shown. Further evidence of the specificity of interphase transfer in micellar-extraction systems is independent and cooperative influence of substrate molecular structure and hydrophobicity on their distribution. The appearance of host-guest phenomenon in cloud point extraction systems that is inherent in organized systems with molecules of the receptors was established. The possibility of describing reagent distribution using regressions that consider substrate hydrophobicity and molecular structure in the cloud point extraction systems was shown.  相似文献   
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两种新型双极有机小分子发光材料的合成与发光   总被引:3,自引:0,他引:3  
设计和合成了两种新的具有“双极(bipolar)”性质和发光性能的有机小分子化合物N-[4-(5-(2-苯基喹啉-4)-1,3,4-噁二唑-2)苯基]-N'-苯基-N,N'-二苯基-1,1'-联苯基-4,4'-二胺(TPDOPQ)和N,N'-双{4-[5-(2-苯基喹啉-4-基)-1,3,4-噁二唑-2]苯基}-N,N'-二苯基-1,1'-联苯基-4,4'-二胺[TPD(OPQ)2]. 用1H NMR, MS和元素分析进行了表征, 研究了化合物的热稳定性和光致发光性质, 并用循环伏安法测定了其电化学性能. 结果表明, 这两种合成的有机化合物同时具备空穴传导和电子输入双重功能, 光致发光性能优良, 热稳定性好, 能形成均衡薄膜, 因此可作为制作有机电致发光器件的候选材料.  相似文献   
17.
Vortex-induced vibration of two side-by-side elastic beams in a cross flow is numerically studied. The two beams are identical and fixed at both ends. In the numerical approach, the Euler-Bernoulli beam theory is used to model the beam vibration, and the laminar Navier-Stokes equations are solved to give the flow field. The flow equations are resolved using a finite element method and the flow-induced forces are calculated at every time step in order to correctly reflect the fluid-beam interaction. The beam response is calculated using the modal analysis method. Free vibrations of the two beams with three pitch ratios, T/D=1·13, 1·7 and 3·0, where T is the gap between the centers of the two beams and D is the beam diameter, are simulated at Re=800. Results obtained are compared with experimental measurements and other numerical results obtained assuming a two-degree-of-freedom (2-d.o.f.) model. The agreement is good in general. Correlation analysis is carried out, showing that the phase relation is different for differentT /D. The short-time Fourier transform (STFT) method is used to carry out the spectral analysis, along with the conventional auto-regressive moving averaging (ARMA) method for comparison. The STFT analysis shows that the time evolution of fluid force and beam vibration for T/D=1·13 and 3·0 are stationary. For theseT /D ratios, the STFT results are consistent with the ARMA results, but give a clearer picture of the higher order harmonics. For T/D=1·7, the time evolution is non-stationary. The STFT analysis shows that there are three types of frequency spectrum for the fluid force, with one, two, and three dominant frequencies respectively. The spectra intermittently change in a random way during the evolution. The ARMA results, though consistent with previous experiments, can only reveal a particular feature of the three different types of spectrum. This suggests that the STFT method is more appropriate to analyze the spectra of non-stationary time series in the study of flow-induced vibrations.  相似文献   
18.
新型双极有机小分子化合物及其Al3+配合物的合成与发光   总被引:2,自引:1,他引:2  
合成了一种新的具有“双极”(bipolar)性质的有机小分子蓝色发光材料2-(5-(4-(二苯胺基)苯基)-1,3,4-噁二唑-2-)苯酚[2(5-(4-(diphenylamino)phenyl)-1,3,4-oxadiazol-2-yl)phenol, HPOT], 并以HPOT为配体, 与铝离子配位, 合成了三(2-(5-(4-(二苯胺基)苯基) 1,3,4-噁二唑-2-)苯酚)合铝[tri(2-(5-(4-(diphenylamino)phenyl)-1,3,4-oxadiazol-2-yl)phenonate)aluminum, AlPOT]配合物. 用 1 H NMR、 HRMS和元素分析进行了表征, 并测定了两种化合物的光致发光性质和热稳定性. 结果表明: 两种新化合物的热稳定性好, 光致发光性能优良, 是制作有机电致发光器件的候选材料.  相似文献   
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