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Eu(p-PBA)_3phen1/2H_2O的高分辨光谱和Raman光谱Eu(p-PBA)3phen1/2H2O的高分辨光谱和Raman光谱*张颖唐波金林培(北京师范大学化学系,北京100875)吕少哲黄世华(中国科学院激发
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配合物Eu(p-PBA)3phen1/2H2O(p-PBA:对苯基苯甲酸酸根离子;phen:邻菲咯啉)在紫外光激发下,能发出很强的红色荧光.以Eu(Ⅲ)离子为光谱探针,77K下测得其高分辨激发和发射光谱,选择激发配合物的5D0能级,得到两组不同的发光光谱,表明配合物中Eu(Ⅲ)离子有两种不同的化学环境.配合物的喇曼光谱中,羧基阴离子的反对称伸缩振动和对称伸缩振动谱带是明显分裂和带肩峰的宽带,说明配合物中羧基同时存在多种配位方式 相似文献
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Assessment of different reconstruction techniques for implementing the NVSF schemes on unstructured meshes
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Three new far‐upwind reconstruction techniques, New‐Technique 1, 2, and 3, are proposed in this paper, which localize the normalized variable and space formulation (NVSF) schemes and facilitate the implementation of standard bounded high‐resolution differencing schemes on arbitrary unstructured meshes. By theoretical analysis, it is concluded that the three new techniques overcome two inherent drawbacks of the original technique found in the literature. Eleven classic high‐resolution NVSF schemes developed in the past decades are selected to evaluate performances of the three new techniques relative to the original technique. Under the circumstances of arbitrary unstructured meshes, stretched meshes, and uniform triangular meshes, for each NVSF scheme, the accuracies and convergence properties, when implementing the four aforementioned far‐upwind reconstruction techniques respectively, are assessed by the pure convection of several scalar profiles. The numerical results clearly show that New‐Technique‐2 leads to a better performance in terms of overall accuracy and convergence behavior for the 11 NVSF schemes. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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We describe the development and validation of a high-resolution screening (HRS) platform which couples gradient reversed-phase
high-performance liquid chromatography (RP-HPLC) on-line to estrogen receptor α (ERα) affinity detection using fluorescence
polarization (FP). FP, which allows detection at high wavelengths, limits the occurrence of interference from the autofluorescence
of test compounds in the bioassay. A fluorescein-labeled estradiol derivative (E2-F) was synthesized and a binding assay was
optimized in platereader format. After subsequent optimization in flow-injection analysis (FIA) mode, the optimized parameters
were translated to the on-line HRS bioassay. Proof of principle was demonstrated by separating a mixture of five compounds
known to be estrogenic (17β-estradiol, 17α-ethinylestradiol and the phytoestrogens coumestrol, coumarol and zearalenone),
followed by post-column bioaffinity screening of the individual affinities for ERα. Using the HRS-based FP setup, we were
able to screen affinities of off-line-generated metabolites of zearalenone for ERα. It is concluded that the on-line FP-based
bioassay can be used to screen for the affinity of compounds without the disturbing occurrence of autofluorescence. 相似文献
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用新发展的超瑞利散射(HRS)技术(一种非相干的方法)研究了表面富镉的CdS纳米粒子的二阶非线性光学性质。结果表明每个纳米粒子的二次非线性极化率β值在10^-26esu量级,这是目前报导的具有最大β值的溶液物种之列。探讨了CdS纳米粒子产生二阶非线性的机制。认为纳米粒子大的比表面及表面缺陷结构对CdS纳米粒子的二阶光学非线性有很大影响。另外,双光子吸收诱导的共振增强作用亦可能贡献CdS纳米粒子的HRS信号,这种双光子共振吸收被其双光子荧光谱所证实。 相似文献
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A refined r‐factor algorithm for implementing total variation diminishing (TVD) schemes on arbitrary unstructured meshes, referred to henceforth as a face‐perpendicular far‐upwind interpolation scheme for arbitrary meshes (FFISAM), is proposed based on an extensive review of the existing r‐factor algorithms available in the literature. The design principles, as well as the respective advantages and disadvantages, of the existing algorithms are first systematically analyzed before presenting the FFISAM. The FFISAM is designed to combine the merits of various existing r‐factor algorithms. The performance of the FFISAM, implemented in 10 classical TVD schemes, is evaluated against four two‐dimensional pure‐advection benchmark test cases where analytical solutions are available. The numerical results clearly show that the FFISAM leads to a better overall performance than the existing algorithms in terms of accuracy and convergence on arbitrary unstructured meshes for the 10 classical TVD schemes. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Beom-Seok Lee Bo-Yun Kim Ji-Hyeon Lee Jong Hee Yoo Kwon Hong Sahn Nahm 《Current Applied Physics》2014,14(12):1825-1830
Pt/TiO2/TiN device with the amorphous TiO2 film grown at room temperature under an oxygen partial pressure of 1.0 mTorr showed reliable bipolar switching behavior. During the electroforming process, a large number of oxygen vacancies formed in the TiO2 film and accumulated at the Pt/TiO2 interface. The barrier height of the Schottky contact of the Pt/TiO2 interface was reduced owing to the presence of these oxygen vacancies, resulting in the low-resistance state (LRS). Moreover, oxygen ions diffused into the TiN electrode during the electroforming and set processes. On the other hand, the oxygen ions in the TiN electrode diffused out and reacted with oxygen vacancies in the TiO2 film during the reset process, and the device changed from the LRS to the high-resistance state (HRS). Conduction in the LRS and HRS can be attributed to Ohmic conduction and the trap controlled space charged limited mechanism, respectively. 相似文献
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A series of new heterocyclic chromophores 3-6 were synthesized in moderate to excellent yields by condensation of 5,6-phenantroline-dione with formyl-thiophene derivatives 1-2 in the presence of ammonium acetate in glacial acetic acid. These chromophores possess an (oligo)thienyl π-conjugated system attached to an imidazo-phenanthroline moiety. These derivatives were evaluated concerning their solvatochromic properties, thermal stabilities, and molecular optical nonlinearities. 相似文献
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Synthesis and second-order nonlinear optical properties of new chromophores containing benzimidazole, thiophene, and pyrrole heterocycles 总被引:1,自引:0,他引:1
A new series of thermally stable benzimidazole-based nonlinear optical (NLO) chromophores 4 and 5 have been developed. These chromophores possess a thienylpyrrolyl π-conjugated system attached to functionalized benzimidazole heterocycles. This feature leads to robust chromophores with excellent solvatochromic properties, high thermal stabilities and good molecular optical nonlinearities. 相似文献
10.
M. Helena Garcia Pedro Florindo M. Teresa Duarte Jürgen Heck Jan Holtmann 《Journal of organometallic chemistry》2008,693(18):2987-2999
A new family of three-legged piano stool structured organometallic compounds containing the fragment η5-cyclopentadienyl-ruthenium(II)/iron(II) has been synthesized to evaluate the existence of electronic metal to ligand charge transfer upon coordination of the novel benzodithiophene ligands (BDT), benzo[1,2-b;4,3-b′]dithiophen-2-carbonitrile (L1) and benzo[1,2-b;4,3-b′]dithiophen-2′nitro-2-carbonitrile (L2). All the compounds were characterized by 1H, 13C, 31P NMR, IR and UV-Vis. spectroscopies and their electrochemistry studied by cyclic voltammetry. The X-ray structures of [Ru(η5-C5H5)(PPh3)2(NCC10H5S2)][PF6] (1Ru), [Ru(η5-C5H5)(PPh3)2(NCC10H5S2)][CF3SO3] (1′Ru), [Ru(η5-C5H5)(DPPE)(NCC10H5S2)][PF6] 2Ru and [Fe(η5-C5H5)(DPPE)(NCC10H5S2)][PF6] (2Fe) were determined by X-ray diffraction showing centric crystallization on groups and P21/n, respectively.Quadratic hyperpolarizabilities (β) of some of the complexes (2Fe, 2Ru and 3Fe) have been determined by hyper-Rayleigh scattering (HRS) measurements at a fundamental wavelength of 1500 nm, to minimize the probability of fluorescence due to two-photon absorption and to reduce the effect of resonance enhancement, in order to estimate static β values. 相似文献