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101.
REN Ji-Rong XU Dong-Hui ZHANG Xin-Hui LI Ran 《理论物理通讯》2007,47(5):944-948
In this paper, using the Φ-mapping theory, it is shown that two kinds of topological defects, i.e., the vortex lines and the monopoles exist in the helical configuration of magnetic field in triplet superconductors. And the inner topological structure of these defects is studied. Because the knot solitons in the triplet superconductors are characterized by the Hopf invariant, we also establish a relationship between the Hopf invariant and the linking number of knots family, and reveal the inner topological structure of the Hopf invariant. 相似文献
102.
由于测定方法的不同,对C60的三线态本征寿命的数值一直存在争议.室温下C60的荧光和磷光较弱,利用时间分辨热透镜技术测量C60的三线态本征寿命具有以下优点:不需要其它参比样品;信号对热灵敏,因而适用于稀溶液. 相似文献
103.
Photoinduced electron transfer (PET) was studied in toluene solutions of the Pd-porphyrin-quinone (Pd-PQ) dyad by flash photolysis
in the picosecond time range and by a luminescence method. It is found that Pd-PQ has a high rate of intercombination conversion
Kisc=(7.7±0.2)·1010 sec−1. Competing intramolecular PET occurs from the lower excited singlet state of the dyad with the rate constant K
et
s
=(2.7 ±0.3)·1010 sec−1. Therefore, ∼74% of excited molecules from the dyad make a transition to the triplet T1 state and 26% take part in intramolecular PET resulting in formation of radical products. The radical products relax to the
ground state with the rate constant K=(7.4±0.2)·109 sec−1.
Institute of Molecular and Atomic Physics of the National Academy of Sciences of Belarus, 70, F. Skorina St., Minsk, 220072,
Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 1, pp. 11–18, January–February, 1999. 相似文献
104.
一种新型香豆素酮可见光敏化染料的合成及其光引发性质的研究 总被引:3,自引:0,他引:3
高效的可见光光敏引发体系是目前光聚合研究中的重要领域.3,3′-二(7-二乙胺基)香豆素酮(R)已被公认为一种高效的可见光聚合敏化染料,并可以与Ar+激光488 nm波长匹配.本文新合成了一种染料3-(4-二乙胺基-苯丙烯酰基)-7-二乙胺基香豆素(S).实验发现在普通碘钨灯照射下,S/邻氯六芳基双咪唑(HABI)体系具有比已有高效染料R/HABI体系更快的光漂白速度和更高的引发聚合效率,是一种新型高效的可见光光敏聚合引发体系.而且S在不同溶剂中的最大吸收波长在452~489 nm之间,比R红移16~30 nm,因此该体系可以更好地与Ar+ (488 nm)激光器匹配.本文对该染料的光敏化机理进行了探讨. 相似文献
105.
Dr. Shadab Gharaati Cui Wang Dr. Christoph Förster Florian Weigert Dr. Ute Resch-Genger Prof. Dr. Katja Heinze 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(5):1003-1007
Photon upconversion has enjoyed increased interest in the last years due to its high potential for solar-energy harvesting and bioimaging. A challenge for triplet–triplet annihilation upconversion (TTA-UC) processes is to realize these features in solid materials without undesired phase segregation and detrimental dye aggregation. To achieve this, we combine a palladium porphyrin sensitizer and a 9,10-diphenylanthracene annihilator within a crystalline mesoporous metal–organic framework using an inverted design. In this modular TTA system, the framework walls constitute the fixed sensitizer, while caprylic acid coats the channels providing a solventlike environment for the mobile annihilator in the channels. The resulting solid material shows green-to-blue delayed upconverted emission with a luminescence lifetime of 373±5 μs, a threshold value of 329 mW cm−2 and a triplet–triplet energy transfer efficiency of 82 %. The versatile design allows straightforward changing of the acceptor amount and type. 相似文献
106.
107.
化学诱导动态电子极化自由基-三重态对理论中选择三重态淬灭的证明 总被引:1,自引:0,他引:1
用时间分辨ESR测出的吩噻嗪/2,2,6,6-四甲基哌啶氮氧自由基(TEMPO)光诱导产生的三重态发射CIDEP信号可用Blätter提出的自由基-三重态对机理来解释,由荧光光谱及脉冲激光光声微量量热实验结果直接证明了Bläter理论关于自由基只选择淬灭双重自旋态的自由基/三重态对中的三重态的假设. 相似文献
108.
109.
Formations of triplet state, molecular cation radical, and phenoxyl radical of 3,4‐methylenedioxy phenol (sesamol, SOH) in organic solvents have been investigated by laser photolysis as well as pulse radiolysis techniques. Photolysis of SOH in cyclohexane has been found to produce both triplet state (λmax ~ 480 nm) and phenoxyl radical (425–430 nm) of SOH by mono‐photonic processes. However, radical cation (λmax = 450 nm) and phenoxyl radical of SOH have been observed on radiolysis in cyclohexane. Further, radiolysis of SOH in benzene has been found to produce phenoxyl radical only. Mechanism of phenoxyl radical formation by photo‐excitation of SOH has been studied and triplet energy level of SOH is estimated to lie between 1.85 and 2.64 eV. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
110.
A. S. Tatikolov Kh. S. Dzhulibekov Zh. A. Krasnaya A. A. Ishchenko V. A. Kuz'min 《Russian Chemical Bulletin》1993,42(4):677-682
Spectral and kinetic properties of photoisomers and triplet molecules of a number of anionic polymethine dyes, namely, differential absorption spectra, rate constants (k
i
) and activation parameters of reversecis-trans-isomerization, and triplet-state-decay rate constantsk
T
are studied by flash photolysis. CINDP/2 calculations of electron density in anionic dyes show thatk
i
andk
T
in polar solvents are determined primarily by the electronic effect of the substituents in themeso-position of the polymethine chain of a dye. The increase ink
i
due to the formation of ion pairs consisting of a dye with a counterion is observed in nonpolar solvents.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 713–718, April, 1993. 相似文献