Theoretical studies on the electronic and geometric structures, the trend in DNA-binding affinities as well as the the structure-activity relationship (SAR) of a series of water-soluble Ru(II) methylimidazole comp...Theoretical studies on the electronic and geometric structures, the trend in DNA-binding affinities as well as the the structure-activity relationship (SAR) of a series of water-soluble Ru(II) methylimidazole complexes, i.e. [Ru(Mehn)4iip]^2+ (1) (MeIm=l-methylimidazole, iip=2-(1H-imidazo-4-group)-lH-imidazo[n,5-f][1,10]phenanthroline), [Ru(MeIm)4tip]^2+ (2) (tip=2-(thiophene-2-group)-lH-imidazo[4,5-f] [i,10]phenanthroline), and [Ru(Melm)42ntz]^2+ (3) (2ntz=2-(2-nitro-l,3-thiazole-5-group)-lH-imidazo[4,5-f][1,10]phenanthroline), were car- ried out using the density functional theory (DFT). The electronic structures of these Ru(II) complexes were analyzed on the basis of their geometric structures optimized in aqueous solution, and the trend in the DNA-binding constants (Kb) was reasonably explained. The results show that the replacement of imidazole ligand by thiophene ligand can effectively improve the DNA-binding affinity of the complex. Meanwhile, it was found that introduc- ing the stronger electronegative N atom and NO2 group on terminal loop of intercalative ligand can obviously reduce the complex's LUMO and HOMO-LUMO gap energies. Based on these findings, the designed complex [Ru(MeIm)42ntz]^2+ (3) can be expected to have the greatest Kb value in complexes 1-3. In addition, the structure-activity relationships and antitumor mechanism were also carefully discussed, and the antimetastatic activity of the designed complex 3 was predicted. Finally, the electronic absorption spectra of this series of complexes in aqueous solution were calculated, simulated and assigned using DFT/TDDFT methods as well as conductor-like polarizable continuum model (CPCM), and were in good agreement with the experimental results.展开更多
Aim To study the relationships between average molecular mass and intrinsic viscosity of polyanhydrides. Methods With chloroform as solvent and petroleum ether as the precipitating agent polyanhydride was separated in...Aim To study the relationships between average molecular mass and intrinsic viscosity of polyanhydrides. Methods With chloroform as solvent and petroleum ether as the precipitating agent polyanhydride was separated into a series of grades with different average molecular mass. The absolute average molecular mass (M) and intrinsic viscosity ([]) of every grade were measured. Results and Conclusion The relationships between [] and M of three typical polyanhydrides were obtained from bi-logarithm coordinate plotting of [] versus M.展开更多
A new method based on the traditional method of ray scanning has been introduced to resolve the problem of judging the color in the chromaticity diagram by employing the line segments approximate curve—— using polyg...A new method based on the traditional method of ray scanning has been introduced to resolve the problem of judging the color in the chromaticity diagram by employing the line segments approximate curve—— using polygonal approximate closed curve. Then a vector coordinate could be used to describe the curve instead of curve equations. So it is easy to judge the topology relation between an area and a point or a locus. And any data processing method has been used to save memory, which makes the improved ray scanning method is quite useful in the measurement of color.展开更多
Organic phototransistors based on high-quality 2,8-dichloro-5,11-dihexyl-indolo[3,2-b]carbazo(CHICZ)single crystals show the highest photoresponsivity of 3×10^3 A W^-1, photosensitivity of 2×10^4 and the det...Organic phototransistors based on high-quality 2,8-dichloro-5,11-dihexyl-indolo[3,2-b]carbazo(CHICZ)single crystals show the highest photoresponsivity of 3×10^3 A W^-1, photosensitivity of 2×10^4 and the detectivity can achieve 8.4×10^14 Jones. We also discovered good linear dependence of log(photosensitivity) versus the wavelength when the devices were illuminated with a series of sameintensity but different-wavelength lights. The organic phototransistors based on CHICZ single crystal have potential applications in wavelength-detection.展开更多
基金ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China (No.20903027), the Natural Science Foundation of Guangdong Province of China (No.9452402301001941), the Medical Scientific Research Foundation of Guangdong Province of China (No.B2013297), and the University Student in Guangdong Province Innovation and Entrepreneurship Train ing Program (No.1057112019 and No.1057112013).
文摘Theoretical studies on the electronic and geometric structures, the trend in DNA-binding affinities as well as the the structure-activity relationship (SAR) of a series of water-soluble Ru(II) methylimidazole complexes, i.e. [Ru(Mehn)4iip]^2+ (1) (MeIm=l-methylimidazole, iip=2-(1H-imidazo-4-group)-lH-imidazo[n,5-f][1,10]phenanthroline), [Ru(MeIm)4tip]^2+ (2) (tip=2-(thiophene-2-group)-lH-imidazo[4,5-f] [i,10]phenanthroline), and [Ru(Melm)42ntz]^2+ (3) (2ntz=2-(2-nitro-l,3-thiazole-5-group)-lH-imidazo[4,5-f][1,10]phenanthroline), were car- ried out using the density functional theory (DFT). The electronic structures of these Ru(II) complexes were analyzed on the basis of their geometric structures optimized in aqueous solution, and the trend in the DNA-binding constants (Kb) was reasonably explained. The results show that the replacement of imidazole ligand by thiophene ligand can effectively improve the DNA-binding affinity of the complex. Meanwhile, it was found that introduc- ing the stronger electronegative N atom and NO2 group on terminal loop of intercalative ligand can obviously reduce the complex's LUMO and HOMO-LUMO gap energies. Based on these findings, the designed complex [Ru(MeIm)42ntz]^2+ (3) can be expected to have the greatest Kb value in complexes 1-3. In addition, the structure-activity relationships and antitumor mechanism were also carefully discussed, and the antimetastatic activity of the designed complex 3 was predicted. Finally, the electronic absorption spectra of this series of complexes in aqueous solution were calculated, simulated and assigned using DFT/TDDFT methods as well as conductor-like polarizable continuum model (CPCM), and were in good agreement with the experimental results.
文摘Aim To study the relationships between average molecular mass and intrinsic viscosity of polyanhydrides. Methods With chloroform as solvent and petroleum ether as the precipitating agent polyanhydride was separated into a series of grades with different average molecular mass. The absolute average molecular mass (M) and intrinsic viscosity ([]) of every grade were measured. Results and Conclusion The relationships between [] and M of three typical polyanhydrides were obtained from bi-logarithm coordinate plotting of [] versus M.
基金Key Projects from Science & Technology Depart ment of Hubei Province(2002AA101B06)
文摘A new method based on the traditional method of ray scanning has been introduced to resolve the problem of judging the color in the chromaticity diagram by employing the line segments approximate curve—— using polygonal approximate closed curve. Then a vector coordinate could be used to describe the curve instead of curve equations. So it is easy to judge the topology relation between an area and a point or a locus. And any data processing method has been used to save memory, which makes the improved ray scanning method is quite useful in the measurement of color.
基金financial support from the Ministry of Science and Technology of China (2017YFA0204503 and 2016YFB0401100)the National Natural Science Foundation of China (51725304, 51633006, 51703159 and 51733004)the Strategic Priority Research Program (XDB12030300) of the Chinese Academy of Sciences
文摘Organic phototransistors based on high-quality 2,8-dichloro-5,11-dihexyl-indolo[3,2-b]carbazo(CHICZ)single crystals show the highest photoresponsivity of 3×10^3 A W^-1, photosensitivity of 2×10^4 and the detectivity can achieve 8.4×10^14 Jones. We also discovered good linear dependence of log(photosensitivity) versus the wavelength when the devices were illuminated with a series of sameintensity but different-wavelength lights. The organic phototransistors based on CHICZ single crystal have potential applications in wavelength-detection.