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Fluorescence quantum yield

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Spectroscopic investigation of defect-state emission in CdSe quantum dots

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Controllable synthesis of dual emissive Ag:InP/ZnS quantum dots with high fluorescence quantum yield. Dual-emissive and color-tunable Mn-doped InP/ZnS quantum dots via a growth-doping method. Boron regulated dual emission in B, N doped graphene quantum dots. Enhanced tunable dual emission of Cu:InP/ZnS quantum dots enabled by introducing Ag ions.. Defect passivation introduced through surface reconstruction in TOPO capped CdSe quantum dots for enhancement in quantum yield.

Investigation of solvent effect on photophysical properties of some sulfonamides derivatives

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The shifts in absorption and fluorescence spectra and the changes in the fluorescence quantum yield and lifetime values occurred depending on the solvent. For all solvents, it was observed that the fluorescence property of S11 is weaker and quantum yield of S11 is lower than S10. have higher quantum yield in the polar aprotic solvent. The ground and excited state dipole moments of compounds were also calculated using polarity functions and Stokes shifts.

Highly sensitive fluorometric method based on nitrogen-doped carbon dot clusters for tartrazine determination in cookies samples

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The yellow solution was used by 1/1250 (V/V) dilution with deionized water in the fluorescence measurements.. Determination of the quantum yield. To determine the relative fluorescence quantum yield of the CDs ( Φ x. The emission (excited at 320 nm) and absorption spectra of the CDs and quinine sulfate at different concentrations were recorded.

Investigation of the photophysical and photochemical behavior of substituted zinc phthalocyanines and their water-soluble quaternized derivatives

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Fluorescence lifetime values of the quaternized complexes (8 and 9) increased with addition of Triton-X 100 with respect to the increasing fluorescence quantum yield due to the reduction of aggregation. For all studied complexes, the τ F values are lower than those of standard ZnPc in DMSO. In contrast to the τ F values, the natural radiative lifetimes ( τ 0 ) of the MPc complexes (6–9) are higher than those of standard ZnPc.

Novel BODIPY-bridged cyclotriphosphazenes

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The fluorescence quantum yields ( Φ F ) of compounds 4–6 and 4P–6P were calculated by the relative procedure in Eq. where the areas under the fluorescence emission curves of the compounds (4–6 and 4P–6P) and the standard are F and F Std , respectively. A and A Std represent the absorbances of compounds 4–6 and 4P–6P, respectively.. η values, as the refractive indices of the solvents, were considered in the determination of the fluorescence quantum yields in different solvents.

Synthesis, optical, and structural properties of bisphenol-bridged aromatic cyclic phosphazenes

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To calculate the fluorescence quantum yield, refractive indices (n) of the solvents were used due to the dissolution of compounds 5–8 and the standard in different solvents. As one of the most widely used standards in the literature, quinine sulfate (Φ F = 0.54), which was dissolved in 0.1 M H 2 SO 4 , was used to calculate the fluorescence quantum yields of compounds 5–8 [35].

Synthesis of 7,12-bis(4-(di(1H-pyrrol-2-yl)methyl)phenyl)benzo[k]fluoranthene from a new dialdehyde as a novel fluorometric bis-Dipyrromethane derivative

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The fluorescence quantum yield for the three compounds was determined in the chloroform relative to quinine sulfate dissolved in H 2 SO 4 (0.1 M). In the majority of uses associated with dipyrromethanes, the UV spectroscopic properties and the fluorescence molecule absorption are important. In the UV spectroscopic studies conducted by Saranya et al. In another paper published by Han et al. However, the products had good potency in the nondoped OLED devices.

Synthesis of tetrakis bromine terminated phthalocyanine and its methyl methacrylate polymers via ATRP

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Similar to zinc Pcs in the literature, the fluorescent quantum yield (Φ F) value for ZnPc-Br was found to 0.29. The fluorescence quantum yield of ZnPc-PMMAs could not be calculated because there were not any references available for them.. It can be seen that the transmittances of pure PMMA and ZnPc-PMMA synthesized using Pc as an initiator are not very different, so we can say that using Pc as an initiator does not have a negative effect on the transmittance of the films.

A green light emitting polymer in a PMMA matrix: oligo(azomethine-ether) with benzothiazole moieties

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Oligomer film in the PMMA matrix emitted a fine green light with a fluorescence quantum yield (QY) of 3.30%. free hydroxyl groups are found in the resulting polymer’s structure.

Microwave-assisted synthesis of novel nonperipherally substituted metallophthalocyanines bearing (7-(trifluoromethyl)quinolin-4-yl)oxy groups

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The fluorescence quantum yield was calculated as 0.048. Absorption (green), excitation (red), and emission (blue) spectra for compound 2 in DMF. 39 The fluorescence lifetimes ( τ F ) and natural radiative lifetimes ( τ o ) of the ZnPc (2) were calculated as 0.49 and 10.30 ns, respectively..

A water-soluble perylene derivative for live-cell imaging

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Recently, fluorescent dyes for living cells staining based on water-soluble perylene diimide (PDI) derivatives have attracted considerable interest because of their high fluorescence quantum yields and outstanding photochemical stabilities. 1 − 5 PDIs are chromophores that exhibit high fluorescence quantum yields close to unity 6,7 and the photostability of the PDI fluorophores is significantly higher than that of other available fluorophores. 13,14 Recently, Proen¸ca and coworkers reported a set

A magnetic affinity approach to identify plant GABA-binding proteins

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Probe R was designed based on CGP64213, a high-affinity antagonist of GABA B receptor (Figures 1A and 1B). it possesses a high environment-independent fluorescence quantum yield, making it an important tool in a variety of imaging applications (Karolin et al., 1994). Imaging of GABA-binding sites using probes Before the labeling studies in plant protoplasts, the probes were first evaluated for their ability to label GABA B receptors in rat brain tissue sections in situ labeling studies..

Boron-containing tetrapyrroles

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Synthesis of compounds 95 and 96.. 56 The anionic conjugate 95 exists mainly as a monomer in polar organic solvents and has fluorescence quantum yields in the region of 0.2–0.3. Carbon–carbon bond forming reactions are key steps in the preparation of complex bioactive molecules. One of the most important carbon–carbon bond-forming methodology is the cross-coupling reaction of organoboron compounds (Suzuki synthons) with organic electrophiles catalyzed by a palladium (Pd) complex.

Synthesis, characterization, and photophysical and photochemical properties of 3-(4-phenyloxy)coumarin containing metallo- and metal-free phthalocyanines

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Fluorescence quantum yields ( Φ F ) and lifetimes (τ F ) (2a/3a, 2c/3c, and 2d/3d) were determined by the comparative method in the literature. of the samples (2a/3a, 2c/3c, and 2d/3d) were determined in DMF by using the photo-irradiation set-up described in the literature. Determination of photodegradation quantum yields ( Φ d ) was carried out as previously described in the literature.

Newly synthesized peripherally octa-substituted zinc phthalocyanines carrying halogen terminated phenoxy-phenoxy moiety: Comparative photochemical and photophysical features

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Fluorescence quantum efficiencies of the octa-connected Pcs are higher than unsubstituted ZnPc;. Significant effect of halogen atom types (F, Cl, Br) on the Pcs on Φ F values of 4, 5 and 6 were not observed in the solutions. Singlet oxygen quantum yields(Φ Δ. The effect of some factors consisting of the substituent, and the terminated halogens atom types on the “ 1 O 2 ” quantum yields were investigated by applying a photochemical method based on the chemical quenching.

Investigation of photochemical and photophysical properties of novel silicon(IV) phthalocyanines and their µ-oxo dimers

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Electronic absorption spectral changes for DPBF during the determination of singlet oxygen quantum yield in DMF.. Electronic absorption spectral changes for compound 3a during the determination of singlet oxygen quantum yield in DMF at a concentration of 1×10 -5 M.. Electronic absorption spectral changes for compound 3b during the determination of singlet oxygen quantum yield in DMF at a concentration of 1×10 -5 M..

Principles of Fluorescence Spectroscopy

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The quantum yield of the unknown is calculated using. In fact, this is one of the more common errors. where d is the thickness of the sample. Some characteristics of the fluorescence of quinine.. Absorption and emission spectra of the enzyme cofactors NADH and FAD.. 3.1) except for a phosphate group on the 2'-position of the ribose. Some of the more widely used probes are shown in Figure 3.8. Fluorescein is one of the least photostable dyes (Figure 3.14). 87–88 The dependence of the IXP.

Photochromic and fluorescence properties of coumarin fulgimides

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Quantum yields for the ring-closure ( Φ E → C ) photoreactions for 5E–8E were determined using the actinometer Aberchrome 540, as described by Heller et al [25]. in toluene at room temperature were found to be 27. The reason of lower quantum yield could be explained by the larger aromatic stabilization energy [26] of the thiophene ring (77.6 kJ/mol) compared to that of the furan ring (61.7 kJ/mol) on other fulgimides.

Diphenylethoxy-substituted metal-free and metallophthalocyanines as potential photosensitizer for photodynamic therapy: synthesis and photophysical and photochemical properties

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Photodegradation quantum yield ( Φ d ) determinations were performed as described in the literature. In The Porphyrins: Physical Chemistry, Part A

Graphitic carbon nitride quantum dots: Synthesis and applications

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GRAPHITIC CARBON NITRIDE QUANTUM DOTS:. Graphitic-carbon nitride quantum dots (g-CNQDs), a rising star in the carbon nitride family, has shown great potential in many fields including chemical and biomedical applications due to their good biocompatibility, stable fluorescence, high quantum yield, and nontoxicity. Keywords: graphitic carbon nitride quantum dots (g-CNQDs).