Nanofibrous pyrolusite （β-MnO2） was synthesized. The particle shape changes from nanofibers to nanoparticles after grinding, and the phase structure does not change. The local environment around the central mangane...Nanofibrous pyrolusite （β-MnO2） was synthesized. The particle shape changes from nanofibers to nanoparticles after grinding, and the phase structure does not change. The local environment around the central manganese ion has a slight change in nanoparticles related to nanofibers. Fourier transform infrared （FTIR） spectra showed that A2u mode frequency shifts from 514 cm-1 to 574 cm-1 to 617 cm-1 gradually while the particle shape and size change from long nanofibers to short fibers and to nanoparticles. The extra vibrational band that is unpredicted by factor group analysis originates from the contribution of A2u mode of the particles with different sizes and shapes in the studied sample. On the basis of Rietveld refinement analysis of XRD profiles and the FTIR spectra, we think that two kinds of MnO6 octahedral geometries, i.e., 4 long＋2 short and 4 short＋2 long, could exist in pyrolusites synthesized by different route. The maximum vibrational frequency in the FTIR spectra of pyrolusites is sensitive to these micro-structures. Assignment of four vibrational bands in the middle and far infrared region has been made.展开更多
Fourier transform infrared spectroscopy （FTIR） was employed to study the human epidermis larynx carcinoma cell lines （Hep-2） which were irradiated by different doses of X-ray. The results show that （1） the irrad...Fourier transform infrared spectroscopy （FTIR） was employed to study the human epidermis larynx carcinoma cell lines （Hep-2） which were irradiated by different doses of X-ray. The results show that （1） the irradiation of X-ray damages the structure of the CH3 groups of the thymine in DNA, which restrains the reproduction of Hep-2 cells effectively, （2） the 8 Gy dose of X-ray irradiation changes the framework and the relative contents of some proteins, lipids and the nucleic acid molecules intercellular in the greatest degree, and （3） the 8 Gy dose of X-ray irradiation is the best irradiation dose for lowering the degree of the cancerization of Hep-2 cells according to the criteria for the degree of the cancerization reported recently. Meanwhile, the apoptosis of these cells were detected by using flow cytometry （FCM） primarily. It shows that the apoptotic ratio of the Hep-2 cells depends on the irradiation dose to some extent, but is not linearly. And the apoptotic ratio of the 12 Gy dose group is the maximum （20.36%）, but the apoptotic ratios of the 2 to 8 Gy dose groups change little.展开更多
文摘Nanofibrous pyrolusite （β-MnO2） was synthesized. The particle shape changes from nanofibers to nanoparticles after grinding, and the phase structure does not change. The local environment around the central manganese ion has a slight change in nanoparticles related to nanofibers. Fourier transform infrared （FTIR） spectra showed that A2u mode frequency shifts from 514 cm-1 to 574 cm-1 to 617 cm-1 gradually while the particle shape and size change from long nanofibers to short fibers and to nanoparticles. The extra vibrational band that is unpredicted by factor group analysis originates from the contribution of A2u mode of the particles with different sizes and shapes in the studied sample. On the basis of Rietveld refinement analysis of XRD profiles and the FTIR spectra, we think that two kinds of MnO6 octahedral geometries, i.e., 4 long＋2 short and 4 short＋2 long, could exist in pyrolusites synthesized by different route. The maximum vibrational frequency in the FTIR spectra of pyrolusites is sensitive to these micro-structures. Assignment of four vibrational bands in the middle and far infrared region has been made.
基金the Science and Technol-ogy Department of Henan province (No.0624410052)the key Ion Beam Bioengineering Laboratory of Henan Province+1 种基金the Pathology Laboratory of Zhengzhou Uni-versitythe People's Hospital of Henan Province.
文摘Fourier transform infrared spectroscopy （FTIR） was employed to study the human epidermis larynx carcinoma cell lines （Hep-2） which were irradiated by different doses of X-ray. The results show that （1） the irradiation of X-ray damages the structure of the CH3 groups of the thymine in DNA, which restrains the reproduction of Hep-2 cells effectively, （2） the 8 Gy dose of X-ray irradiation changes the framework and the relative contents of some proteins, lipids and the nucleic acid molecules intercellular in the greatest degree, and （3） the 8 Gy dose of X-ray irradiation is the best irradiation dose for lowering the degree of the cancerization of Hep-2 cells according to the criteria for the degree of the cancerization reported recently. Meanwhile, the apoptosis of these cells were detected by using flow cytometry （FCM） primarily. It shows that the apoptotic ratio of the Hep-2 cells depends on the irradiation dose to some extent, but is not linearly. And the apoptotic ratio of the 12 Gy dose group is the maximum （20.36%）, but the apoptotic ratios of the 2 to 8 Gy dose groups change little.
