为探究青海省植被固碳量时空演变及其驱动因子,基于2000—2020年净初级生产力(NPP)数据和土壤呼吸模型计算得到植被净生态系统生产力(NEP),采用趋势分析、偏相关分析及地理探测器等方法对青海省植被NEP时空演变及驱动因子进行定量分析...为探究青海省植被固碳量时空演变及其驱动因子,基于2000—2020年净初级生产力(NPP)数据和土壤呼吸模型计算得到植被净生态系统生产力(NEP),采用趋势分析、偏相关分析及地理探测器等方法对青海省植被NEP时空演变及驱动因子进行定量分析。结果表明:青海省植被NEP在近20 a间波动上升,年均增幅为1.54 g C·m^(-2)·a^(-1);年均植被NEP空间变化差异较大,由东南向西北递减,71.08%的区域保持不变或增加;对植被NEP解释力最强的是NDVI,降水、气温、人口密度等气候与人为因子对NEP的空间分异解释力较强;由于双因子交互作用会增强对植被NEP空间分异的解释力,因此在未来提升青海省固碳能力时,要注意多因子协同作用。展开更多
Ni-doped ZnO thin films (Ni concentration up to 10 mol%) were generated on Si (100) substrates by a sol-gel technique. The films showed wurtzite structure and no other phase was found. The chemical state of Ni was fou...Ni-doped ZnO thin films (Ni concentration up to 10 mol%) were generated on Si (100) substrates by a sol-gel technique. The films showed wurtzite structure and no other phase was found. The chemical state of Ni was found to be bivalent by X-ray photoelectron spectroscopy. The results of magnetic measurements at room temperature indicated that the films were ferromagnetic, and magnetic moment decreased with rise of Ni concentration. The magnetization of Ni (10 mol%)-doped ZnO film annealed in nitrogen was lower than that annealed in argon, suggesting that the density of defects had an effect on ferromagnetism.展开更多
This letter reports the influence of branches and bromine substitution of the photosensitizers on one-and two-photon absorption generation of singlet oxygen.Near-infrared femtosecond Ti:squassier laser was utilized to...This letter reports the influence of branches and bromine substitution of the photosensitizers on one-and two-photon absorption generation of singlet oxygen.Near-infrared femtosecond Ti:squassier laser was utilized to determine two-photon properties of the photosensitizers tuning wavelength from 700 to 880 nm at intervals of 20 nm.One-and two-photon optical and photophysical properties of the photosensitizers show significant dependence on the branches and substituted bromine atoms.展开更多
文摘为探究青海省植被固碳量时空演变及其驱动因子,基于2000—2020年净初级生产力(NPP)数据和土壤呼吸模型计算得到植被净生态系统生产力(NEP),采用趋势分析、偏相关分析及地理探测器等方法对青海省植被NEP时空演变及驱动因子进行定量分析。结果表明:青海省植被NEP在近20 a间波动上升,年均增幅为1.54 g C·m^(-2)·a^(-1);年均植被NEP空间变化差异较大,由东南向西北递减,71.08%的区域保持不变或增加;对植被NEP解释力最强的是NDVI,降水、气温、人口密度等气候与人为因子对NEP的空间分异解释力较强;由于双因子交互作用会增强对植被NEP空间分异的解释力,因此在未来提升青海省固碳能力时,要注意多因子协同作用。
基金Supported by the National Natural Science Foundation of China (Grant No.10674059)the National Basic Research Program of China (“973” Project) (Grant No.2005CB623605)
文摘Ni-doped ZnO thin films (Ni concentration up to 10 mol%) were generated on Si (100) substrates by a sol-gel technique. The films showed wurtzite structure and no other phase was found. The chemical state of Ni was found to be bivalent by X-ray photoelectron spectroscopy. The results of magnetic measurements at room temperature indicated that the films were ferromagnetic, and magnetic moment decreased with rise of Ni concentration. The magnetization of Ni (10 mol%)-doped ZnO film annealed in nitrogen was lower than that annealed in argon, suggesting that the density of defects had an effect on ferromagnetism.
基金supported by the National Natural Science Foundation of China (20776165,20702065,20872184)the Fundamental Research Funds for the Central Universities (CDJZR10220006)+1 种基金Chongqing Natural Science Foundations (CSTC2012jjB50007)Fang Gao appreciates warm encouragements from the Program of New Century Excellent Talents in University (NCET-10-0876)
文摘This letter reports the influence of branches and bromine substitution of the photosensitizers on one-and two-photon absorption generation of singlet oxygen.Near-infrared femtosecond Ti:squassier laser was utilized to determine two-photon properties of the photosensitizers tuning wavelength from 700 to 880 nm at intervals of 20 nm.One-and two-photon optical and photophysical properties of the photosensitizers show significant dependence on the branches and substituted bromine atoms.
