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81.
The non-covalent interaction between aPigenin (API) and different functional monomers (α-methylacrylic acid (MAA), acrylamide (AM), 2-vinylpyridine (2-Vpy) and combined functional monomers (AM/2-Vpy)) was determined by UV spectrometry, and a series of apigenin molecularly imprinted polymers (API-MIPs) was synthesized with different functional monomers through molecular imprinting technology. The relationship between the non-covalent interaction of template/functional monomer and absorption of MIPs also was studied. The results showed that the order of the strength of the non-covalent interaction between API and different functional monomers in tetrahydrofuran (THF) is as follows: 2-Vpy〉 AM/2-Vpy〉AM〉MAA, which is positive correlation to the absorption capability of corresponding MIPs, and 2-Vpy is the optimum functional monomer among the used monomer for preparing API- MIPs.  相似文献   
82.
Cheng Y  Li Z  Du B  Zhang X 《The Analyst》2008,133(6):750-752
Integration of rolling circle amplification and sensitive bioluminescent detection of pyrophosphate, a homogeneous and label-free method has been developed for detecting single nucleotide polymorphism.  相似文献   
83.
We investigate theory of single-photon control from a two-level single-molecule source irradiated by laser pulses of various shapes and pulse durations in terms of quantum trajectories which link stochastic dynamics of the radiating source with quantum measurement theory. Using Monte Carlo wave function simulation, we analyze the detailed dissipative dynamics of the single-molecule source and the photon statistics as revealed by repeated Gedanken photon measurement on the single radiating source. We show that much of the photon statistics from the two-level single-molecule single-photon sources, including few-photon emission probability, waiting time distribution, and two-time correlation function of the fluorescent light, can be understood qualitatively from the simple picture of Rabi nutation and pi pulse in terms of pulse areas.  相似文献   
84.
Fullerene‐structural carbon‐based dots (f‐CDs) are synthesized for the first time by chemically oxidizing fullerene molecules (C60) using concentrated HNO3. The lateral sizes of the f‐CDs distribute in the range of 7–20 nm, and the heights mainly range from 0.4 to 1.3 nm with an average value of 0.7 nm. The presence of massive pentagonal carbon units makes the f‐CDs different from most of graphitic‐CDs in structure and morphology. The f‐CDs exhibit unique luminescent properties such as photoluminescence (PL) and electrochemiluminescence. Based on the investigation of the UV–vis absorption and luminescent properties, a novel and reasonable model is proposed for the PL mechanism of f‐CDs. Furthermore, the obtained f‐CDs show low cytotoxicity and have potential application in cell imaging.  相似文献   
85.
Three functionalized derivatives of tetraphenylethylene (TPE), namely, 1,2-bis(4-methoxyphenyl)-1,2-diphenylethene (1), 1,2-bis(4-hydroxyphenyl)-1,2-diphenylethene (2), and 1,2-bis[4-(3-sulfonatopropoxyl)phenyl]-1,2-diphenylethene sodium salt (3), were synthesized and their fluorescence properties were investigated. All the TPE molecules are nonluminescent in the solution state but are induced to emit efficiently by aggregate formation. This novel process of aggregation-induced emission (AIE) is rationalized to be caused by the restriction of intramolecular rotations of the dye molecules in the aggregate state. The possibility of utilizing the AIE effect for protein detection and quantification is explored using bovine serum albumin (BSA) as a model protein, with salt 3 being found to perform as a stable, sensitive, and selective bioprobe.  相似文献   
86.
Photoluminescence of simple arylbenzenes with ready synthetic accessibility is enhanced by two orders of magnitude through aggregate formation; viscosity and temperature effects indicate that the emission enhancement is due to the restriction of their intramolecular rotations in the solid state.  相似文献   
87.
(4-Biphenylyl)phenyldibenzofulvene is weakly luminescent in the amorphous phase but becomes highly emissive upon crystallization; this unusual crystallization-induced emission enhancement effect allows its emission to be repeatedly switched between dark and bright states by fuming-heating and heating-cooling processes.  相似文献   
88.
We have recently reported a novel rearrangement reaction involving an intramolecular metathesis between M-M and Fe-Fe bonds in the dinuclear iron complexes (Me2MMMe2)[η5-C5R4)Fe(CO)]2(μ-CO)2 (M=Si, Ge; R=H, Me):[1-5].In order to extend the applied range of the rearrangement reaction we tried to synthesize the digermyl briged diruthenium analogues. The results showed a great difference between them.  相似文献   
89.
提出一种既不是利用振幅加减,又不是利用强度加减,而且也不同于一般利用互补色进行图象相减的新方法,获得了图象间差异信息的假彩色输出。  相似文献   
90.
王立军  武胜利 《发光学报》1999,20(2):152-154
研制出30个单元的InGAaSp/InGaP/GaAs分别限制双异质结单量子阱激光器列阵,器件外微分量子效率达78%,发向波长808nm,准连续输出的光功率达27W。  相似文献   
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