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151.
配制了Stilbene 420染料溶液。测量了其吸收光谱。以调Q倍频Nd∶YAG激光为抽运源,实现了对Stilbene 420染料的激光光谱和荧光光谱的分析。激光光谱在425 nm处获得最强峰值,半峰高宽(FWHM)为1 nm,光谱范围为420~440 nm。荧光光谱峰值在428.5 nm,与激光最强峰值相差3.5 nm。最高染料转换效率为9.26%。 相似文献
152.
基于非色散紫外算法的一氧化氮气体检测与分析 总被引:1,自引:0,他引:1
提出了一种基于非色散紫外(NDUV)算法,利用光电二极管阵列(PDA)探测器和光谱仪检测一氧化氮气体的分析方法。通过对比分析不同积分次数下一氧化氮吸收谱和无吸收谱内不同波长宽度的总光强,引入光源影响因子F和吸收谱因子B,得到吸光度与浓度的拟合方程及相关系数。结果表明,采用合适的拟合阶数、拟合波长宽度和分析方法,吸光度与浓度的二阶拟合相关系数可达0.999 9以上, 通过拟合方程所获得的待测气体浓度与标准值浓度的误差在3%以内。 相似文献
153.
三方非对称进化博弈行为分析 总被引:2,自引:0,他引:2
随着政府涉入领域以及社会合作谈判领域的增多,三方非对称进化博弈越来越多地出现在现实生活中.但目前国内外对该类型的进化博弈研究甚少,这显然不利于正确地解释和预测该类型的博弈行为.基于此,运用进化博弈论中的“复制动态”思想,对三方非对称的2×2×2进化博弈进行了渐进稳定性分析,完整地给出了其定性行为的等价定量分类和各参与主体不同情况下的稳定性策略,并且用三维立体图演示了不同策略组合的渐进趋势,从而为研究现实生活中该类型的博弈行为提供了一种理论依据. 相似文献
154.
Shintaro Kohata Prof. Hajime Nakanotani Prof. Youhei Chitose Prof. Takuma Yasuda Prof. Youichi Tsuchiya Prof. Chihaya Adachi 《Angewandte Chemie (International ed. in English)》2023,62(44):e202312326
Photon-upconversion in organic molecular systems is one of the promising technologies for future energy harvesting systems because these systems can generate excitons that possess higher energy than excitation energy. The photon-upconversion caused by absorbing ambient heat as additional energy is particularly interesting because it could ideally provide a light-driving cooling system. However, only a few organic molecular systems have been reported. Here, we report the anti-Stokes photoluminescence (ASPL) derived from hot-band absorption in a series of multi-resonance-type thermally-activated delayed fluorescence (MR-TADF) molecules. The MR-TADF molecules exhibited an anti-Stokes shift of approximately 0.1 eV with a high PL quantum yield in the solution state. The anti-Stokes shift corresponded well to the 1–0 vibration transition from the ground state to the excited singlet state, and we further evaluated a correlation between the activation energy for the ASPL intensity and the TADF process. Our demonstration underlines that MR-TADF molecules have become a novel class of ASPL materials for various future applications, such as light-driving cooling systems. 相似文献
155.
Considering the potential bioactivities of natural product and natural product-like compounds with highly complex and diverse structures, the screening of collections and small-molecule libraries for high-throughput screening (HTS) and high-content screening (HCS) has emerged as a powerful tool in the development of novel therapeutic agents. Herein, we review the recent advances in divergent synthetic approaches such as complexity-to-diversity (Ctd) and biomimetic strategies for the generation of structurally complex and diverse indole-based natural product and natural product-like small-molecule libraries. 相似文献
156.
Antunes A de Rossi W Zezell DM 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,64(5):1142-XXXIV
Laser irradiation on hard tissue has produced a resistant surface that is likely to prevent caries. In this study, human enamel and dentine were exposed to nanosecond pulsed Nd:YAG laser with energy densities of 20-40 J/cm(2) and pulse width of 6 ns inducing chemical changes in these tissues. Infrared analysis of human dental enamel and dentine was performed using the KBr method (2mg sample/300 mg KBr). A correlation between non-lased and lased spectra was performed that gives an indication of the changes in organic and inorganic compounds after laser-tissue interaction. Spectra of teeth simultaneously show the inorganic and organic parts of the tissue. The principal bands: amide bands A, I, II, and III from the collagen-matrix, phosphate from the mineral content, and carbonate bands were identified. The normalized area of peak versus peak position was determined. Changes of the bands attributed to the collagen matrix were verified after Nd:YAG irradiation. The present results suggest a chemical modification of organic and mineral compounds by laser. The spectral results indicated an alteration in the absorption bands relative to, essentially, organic compounds. 相似文献
157.
Nemanja Trišović Nebojša Banjac Nataša Valentić Gordana Ušćumlić 《Journal of solution chemistry》2009,38(2):199-208
The absorption spectra of nine compounds structurally related to phenytoin (5,5-diphenylhydantoin) were recorded in twelve
solvents over the range of 200 to 400 nm. The effects of solvent dipolarity/polarizability and solvent/solute hydrogen bonding
interactions were analyzed by means of the linear solvation energy relationship (LSER) concept proposed by Kamlet and Taft.
The lipophilic activity of the investigated hydantoins was estimated by calculation of their log 10
P values. The calculated values of log 10
P were correlated with the ratio of the contributions of specific and non-specific solute/solvent interactions. The correlation
equations were combined with the corresponding ED50 values to generate new equations that demonstrate exact relationship between solute/solvent interactions and the structure-activity
parameters. 相似文献
158.
Plasmonics in the UV region has been widely focused because of the higher energy and the abundant electronic resonances compared to the conventional visible plasmonics. Recently, we have investigated the surface plasmon resonance (SPR) properties of the Al film, aiming for the application as refractive index sensors. Utilizing the UV lights, we expect three advantages: high sensitivity, material selectivity, and surface selectivity. By using an original attenuated total reflectance spectroscopic instrument, Al‐SPR angle and wavelength were investigated with changing environments on the Al film. Al film thickness and materials of prisms on which Al was evaporated were also important factors for the SPR properties. By optimizing the conditions, the Al film worked as a sensor both in air and in liquids. In addition, our established system expands the plasmonics into an even higher energy region than 200 nm, while the UV‐plasmonics have been studied in the wavelength region longer than 200 nm. 相似文献
159.
《化学:亚洲杂志》2018,13(19):2834-2837
Magnetic cooling at low temperature has attracted intensive interest in cryogenics research, which may become important as cooling medium for long‐wave photon detectors to support space exploration. Here, we report a Gd‐based quaternary magnetic refrigerant material, Gd5BSi2O13, containing chains of face‐shared GdO9 polyhedra and geometrically frustrated OGd3 triangles. Magnetic measurements indicate that Gd5BSi2O13 exhibits a large magnetocaloric effect (MCE) about 1.74 times that of the practical magnetic refrigerant GGG (−ΔSm=67.0 J kg−1 K−1). We analyzed the origin of the large MCE by comparing GdIII‐containing compounds with different structures and concentrations of GdIII. 相似文献
160.
简要介绍了中国承担设计和制造任务的ITER计划采购包的构成情况,分析了ITER采购包采用标准的原则和ITER中国采购包引用标准的特点,总结了ITER中国采购包标准化现状。基于当前ITER中国采购包对标准的需求以及着眼于国内磁约束核聚变长远发展需要,讨论提出了当前ITER中国采购包的标准化策略建议。 相似文献