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991.
Atif F. Khan Ravishanker Yadav P. K. Mukhopadhya Sukhvir Singh Charu Dwivedi Viresh Dutta Santa Chawla 《Journal of nanoparticle research》2011,13(12):6837-6846
A distinct enhancement of upconversion luminescence from core to core/shell (C/S) structure under low flux near infrared (NIR)
excitation at 976 nm has been achieved in lanthanide (Er3+, Yb3+)-doped NaYF4 core with undoped NaYF4 shell nanoparticles (NP). A green chemistry approach has been taken to synthesize monodisperse monophasic C/S NP with the
core (~20 nm) and shell (~5 nm) crystallizing into cubic phase. Hydrophobic C/S NP have been further made hydrophilic by coating
a transparent SHMP layer without affecting luminescence. C/S (NaYF4: Er, Yb/NaYF4) NP integrated dye-sensitized solar cell indicated 11.9% enhancement in overall conversion efficiency under AM 1.5 conditions,
due to NIR–visible spectrum modification by fluorescent NPs. The results indicate great potential of such upconverting C/S
nanophosphor in solar cell applications. 相似文献
992.
993.
Synthesis,Characterization and Properties of Expanded Pyriporphyrins: A New Family of Alkylidenyl Porphyrin Homologues Bearing meso‐Exocyclic Double Bonds
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Abeje Abebayehu Dr. Ranjan Dutta Prof. Chang‐Hee Lee 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(39):13850-13856
We present the synthesis and characterization of a new family of expanded meso‐alkylidenyl (2,6‐pyri)porphyrinoids bearing multiple exocyclic double bonds at the meso‐positions. The synthesis was accomplished by using mixed pyrrole condensation. Similar to meso‐alkylidenyl porphyrinoids, this study revealed that pyriporphyrinoids do not possess a porphyrin‐like, global‐aromatic character. The synthesized 2,6‐pyripentaphyrin 1 displays selective ratiometric sensing of pyrophosphate anion in organic solvent. 相似文献
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995.
Dr. Geoffroy Ferru Dr. Benjamin Reinhart Dr. Mrinal K. Bera Prof. Monica Olvera de la Cruz Dr. Baofu Qiao Dr. Ross J. Ellis 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(20):6899-6904
The lanthanide contraction is conceptualized traditionally through coordination chemistry. Here we break this mold in a structural study of lanthanide ions dissolved in an amphiphilic liquid. The lanthanide contraction perturbs the weak interactions between molecular aggregates that drive mesoscale assembly and emergent behavior. The weak interactions correlate with lanthanide ion transport properties, suggesting new strategies for rare‐earth separation that exploit forces outside of the coordination sphere. 相似文献
996.
In this paper, a new approach for the determination of resonance frequencies of a material using stimulated Raman scattering is reported. A numerical model for nonlinear composite Raman susceptibility (CRS) is proposed considering the effect of molecular vibrations. The model considers four parameters for each molecular vibration, termed as quadruplets. Based on this CRS, the theoretical Raman gain in silica fiber is estimated. Genetic algorithm technique is used to find out the quadruplets, resonance frequencies in particular, by matching the estimated Raman gain with its experimental value. Eight optimized resonance frequencies are obtained for silica material. 相似文献
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998.
999.
Reaction of α, β-unsaturated acid chlorides with primary enaminonitriles in presence of triethylamine affords, under very mild conditions, a simple and highly efficient regiospecific synthesis of polysubstituted 3,4-dihydro-2(1H)-pyridones. 相似文献
1000.
Lalit Dutta Syed Imran Ahmad Subhra Kanti Mukherjee Sanjeev Mishra Arshad Khuroo Tausif Monif 《Biomedical chromatography : BMC》2013,27(5):622-635
A sensitive, accurate and highly stereoselective assay for the simultaneous determination of venlafaxine (VEN) and its equipotent metabolite, O‐desmethyl venlafaxine (ODV), in human plasma was developed and validated. Analytes were simultaneously extracted from plasma using solid‐phase extraction and detected by tandem mass spectrometry in positive ion mode with a turbo ion spray interface. Deuterium‐labeled VEN and ODV were used as internal standards. Chromatographic separation was performed on a Chiral AGP column, using a time programmed gradient flow with a total run time of 16 min. The method has a lower limit of quantitation of 0.60 ng/mL. The assay was linear over a range 0.60–300.00 ng/mL for both the enantiomers of VEN and ODV, respectively, with coefficient of correlation > 0.99. The extraction recoveries were >77.0% on an average for all the four analytes. The analytes were found stable in plasma through three freeze (?15 °C) and thaw cycles and under storage at room temperature for 8 h, and also in mobile phase at 10 °C for 54 h. The method has shown good reproducibility, with intra‐ and inter‐day variation coefficients < 9%, for all the analytes, and has proved to be very reliable for analysis of VEN and its metabolite in clinical study samples. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献