SnO2 nanocrystal and rare-earth Eu^3＋ ion co-doped SiO2 thin films are prepared by sol-gel and spin coating methods. The formation of tetragonal rutile structure SnO2 nanocrystals with a uniform distribution is confi...SnO2 nanocrystal and rare-earth Eu^3＋ ion co-doped SiO2 thin films are prepared by sol-gel and spin coating methods. The formation of tetragonal rutile structure SnO2 nanocrystals with a uniform distribution is confirmed by X-ray diffraction and transmission electron microscopy. Fourier transform infrared spectroscopy is used to investigate the densities of the hydroxyl groups, and it is found that the emission intensity from the 5Do-TF2 transitions of the Eu^3＋ ions is enhanced by two orders of magnitude due to energy transfer from the oxygen-vacancy-related defects of the SnO2 nanocrystals to nearby Eu^3＋ ions. The influences of the amounts of Sn and the post-annealing temperatures are systematically evaluated to further understand the mechanism of energy transfer. The luminescence intensity ratio of Eu^3＋ ions from electric dipole transition and magnetic dipole transition indicate the different probable locations of Eu^3＋ ions in the sol-gel thin film, which are further discussed based on temperature-dependent photoluminescence measurements.展开更多
The cry1Ah gene was one of novel insecticidal genes cloned from Bacillus thuringiensis isolate BT8. Two plant expression vectors containing cry1Ah gene were constructed. The first intron of maize ubiqutin1 gene was in...The cry1Ah gene was one of novel insecticidal genes cloned from Bacillus thuringiensis isolate BT8. Two plant expression vectors containing cry1Ah gene were constructed. The first intron of maize ubiqutin1 gene was inserted between the maize Ubiquitin promoter and cry1Ah gene in one of the plant expressing vectors (pUUOAH). The two vectors were introduced into maize immature embryonic calli by microprojectile bombardment, and the reproductively plants were acquired. PCR and Southern blot analysis showed that foreign genes had been integrated into maize genome and inherited to the next generation stably. The ELISA assay to T1 and T2 generation plants showed that the expression of Cry1Ah protein in the construct containing the ubi1 intron (pUUOAH) was 20% higher than that of the intronless construct (pUOAH). Bioassay results showed that the transgenic maize harboring cry1Ah gene had high resistance to the Asian corn borers and the insecticidal activity of the transgenic maize containing the ubi1 intron was higher than that of the intronless construct. These results indicated that the maize ubi1 intron can enhance the expression of the Bt cry1Ah gene in transgenic maize展开更多
The Ti/SnO2-Sb-Mo electrodes doped with different molar ratios of molybdenum（Mo） were prepared by sol—gel method in order to investigate the effect of Mo on the characterization of Ti/SnO2-Sb—Mo electrodes.X-ray d...The Ti/SnO2-Sb-Mo electrodes doped with different molar ratios of molybdenum（Mo） were prepared by sol—gel method in order to investigate the effect of Mo on the characterization of Ti/SnO2-Sb—Mo electrodes.X-ray diffraction（XRD）,field-emission scanning electron microscopy（FE-SEM）,energy dispersive spectrometry（EDS）,and linear scanning voltammetry（LSV） were used to scrutinize the coating material and the electrochemical activity.The concentration of phenol,the value of total organic carbon（TOC）,the mineralization current efficiency（MCE） and the ultraviolet—visible spectroscopy（UV-Vis） spectrum of phenol solution were measured over the electrochemical degradation process of phenol to confirm the phenol degradation characterization of Ti/SnO2-Sb-Mo electrodes.Results showed that the electrode at the Mo content of 1 at.%provided optimal catalytic activity for phenol degradation and the longest life time.The removal percentage of phenol and TOC were 99.62%and82.67%,respectively.The Ti/SnO2-Sb-Mo electrode with 1 at.%of Mo reached maximum MCE of phenol oxidation.The kinetic investigation of phenol and TOC degradation displayed the pseudo-first order reaction model.The Ti/SnO2-Sb-Mo electrode coating with 7 at.%Mo presented the highest oxygen evolution overpotential,indicating the diverse effects for different Mo molar ratio doping.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.61036001)the Natural Science Foundation of Jiangsu Province,China(Grant No.BK2010010)the Fundamental Research Funds for the Central Universities of China(Grant Nos.1112021001 and 1116021003)
文摘SnO2 nanocrystal and rare-earth Eu^3＋ ion co-doped SiO2 thin films are prepared by sol-gel and spin coating methods. The formation of tetragonal rutile structure SnO2 nanocrystals with a uniform distribution is confirmed by X-ray diffraction and transmission electron microscopy. Fourier transform infrared spectroscopy is used to investigate the densities of the hydroxyl groups, and it is found that the emission intensity from the 5Do-TF2 transitions of the Eu^3＋ ions is enhanced by two orders of magnitude due to energy transfer from the oxygen-vacancy-related defects of the SnO2 nanocrystals to nearby Eu^3＋ ions. The influences of the amounts of Sn and the post-annealing temperatures are systematically evaluated to further understand the mechanism of energy transfer. The luminescence intensity ratio of Eu^3＋ ions from electric dipole transition and magnetic dipole transition indicate the different probable locations of Eu^3＋ ions in the sol-gel thin film, which are further discussed based on temperature-dependent photoluminescence measurements.
基金supported by the National Natural Science Fund of China (30970231)the Genetically Modified Organisms Breeding Major Project of China (2014ZX08003001)
文摘supported by the National Natural Science Fund of China （30970231）;the Genetically Modified Organisms Breeding Major Project of China （2014ZX08003001）
基金the National Natural Science Foundation of China (Grant No. 30500039)National Basic Research Program of China (Grant No. 2003CB114201)Basic Scientific Research Foundation for Chinese Central Academy (Biotech-nology Research Institute, CAAS)
文摘The cry1Ah gene was one of novel insecticidal genes cloned from Bacillus thuringiensis isolate BT8. Two plant expression vectors containing cry1Ah gene were constructed. The first intron of maize ubiqutin1 gene was inserted between the maize Ubiquitin promoter and cry1Ah gene in one of the plant expressing vectors (pUUOAH). The two vectors were introduced into maize immature embryonic calli by microprojectile bombardment, and the reproductively plants were acquired. PCR and Southern blot analysis showed that foreign genes had been integrated into maize genome and inherited to the next generation stably. The ELISA assay to T1 and T2 generation plants showed that the expression of Cry1Ah protein in the construct containing the ubi1 intron (pUUOAH) was 20% higher than that of the intronless construct (pUOAH). Bioassay results showed that the transgenic maize harboring cry1Ah gene had high resistance to the Asian corn borers and the insecticidal activity of the transgenic maize containing the ubi1 intron was higher than that of the intronless construct. These results indicated that the maize ubi1 intron can enhance the expression of the Bt cry1Ah gene in transgenic maize
基金financial support from the China Environmental Protection Foundation,Geping Green ActionLiaoning Environmental Research and Education Fund "123 Project"(Grant No.CEPF2012-123-2-10)
文摘The Ti/SnO2-Sb-Mo electrodes doped with different molar ratios of molybdenum（Mo） were prepared by sol—gel method in order to investigate the effect of Mo on the characterization of Ti/SnO2-Sb—Mo electrodes.X-ray diffraction（XRD）,field-emission scanning electron microscopy（FE-SEM）,energy dispersive spectrometry（EDS）,and linear scanning voltammetry（LSV） were used to scrutinize the coating material and the electrochemical activity.The concentration of phenol,the value of total organic carbon（TOC）,the mineralization current efficiency（MCE） and the ultraviolet—visible spectroscopy（UV-Vis） spectrum of phenol solution were measured over the electrochemical degradation process of phenol to confirm the phenol degradation characterization of Ti/SnO2-Sb-Mo electrodes.Results showed that the electrode at the Mo content of 1 at.%provided optimal catalytic activity for phenol degradation and the longest life time.The removal percentage of phenol and TOC were 99.62%and82.67%,respectively.The Ti/SnO2-Sb-Mo electrode with 1 at.%of Mo reached maximum MCE of phenol oxidation.The kinetic investigation of phenol and TOC degradation displayed the pseudo-first order reaction model.The Ti/SnO2-Sb-Mo electrode coating with 7 at.%Mo presented the highest oxygen evolution overpotential,indicating the diverse effects for different Mo molar ratio doping.
