金电极表面植物原生质体的固定化

Barley protoplast was immobilized on poly(dially dimethylammonium) (PDADMAC) modified gold electrode via the electrostatic attraction between the positively charged amine groups of PDADMAC and the negatively charged barley protoplast. STM image reveals that PDADMAC/Au(111) surface displays a nano organized dot(4-6 nm) array structure. The processes of the PDADMAC adsorption and of the barley protoplast immobilization were monitored from the in situ QCM frequency change. The effects of the adsorbed mass and of the density and viscosity of medium on the frequency change of QCM were discussed, respectively. The QCM result shows that the thickness of the adsorbed PDADMAC layer is 2.4 nm

基于CA模型的乌鲁木齐都市圈城市用地扩展模拟研究

借助CA模型技术,基于乌鲁木齐都市圈城市用地发展的特点,构建了模拟多个城市群体扩展的CA模型,重点对模型的转换规则进行了扩展,把用地适宜性约束、城市内部社会经济驱动、城市之间相互作用力、区域生态格局限制、城市发展规模有限这几个方面的作用机制融入到模型的规则制定中,通过宏观约束、中观调节、微观驱动3个层次逐步实现;为了使社会经济数据与CA模型中的空间数据相匹配,对社会经济数据进行了空间化表达;在历史数据的参照下,所构建的模型经过反复调试与修正,模拟结果达到了较为满意的效果;应用此模型模拟了经济优先、生态优先与规划优先3种不同情景下的城市用地扩展,对都市圈城市用地今后的发展起到重要的启示作用

基于不同空间尺度的乌鲁木齐都市圈土地利用/覆被变化研究

新疆乌鲁木齐都市圈是在干旱背景下形成的城市群体地域空间,文章以此为研究区域,基于多源空间数据,利用GIS空间分析方法,在宏观、中观与微观尺度上对都市圈的土地利用/覆被变化进行分析。得出以下结论:①都市圈土地利用/覆被变化在山地、绿洲和荒漠区差异很大,山地与荒漠区的土地覆被变化较弱,绿洲区的用地变化非常显著,其中受人为影响的土地覆被变化尤为明显;②绿洲区的裸地和农业用地在规模上变化最大,城镇、农村居民点和道路的变化幅度最为明显,农业用地与建设用地主要向北部冲积平原扩展,初步形成了以农田为基底的都市圈城市格局;③各城市用地规模悬殊较大,核心城市占主导地位;城市用地扩展在空间上表现出各向异性的特点;核心城市的主要用地变化具有较为明显的圈层分异特征,中小城市的用地初具圈层结构

Immobilization of plant protoplast on gold electrode surface

Barley protoplast was immobilized on poly (dially-dimethylammonium) (PDADMAC) modified gold electrode via the electrostatic attraction between the positively charged amine groups of PDADMAC and the negatively charged barley protoplast. STM image reveals that PDADMAC/Au(Ill) surface displays a nano-organized dot(4-6 nm) array structure. The processes of the PDADMAC adsorption and of the barley protoplast immobilization were monitored from the in situ QCM frequency change. The effects of the adsorbed mass and of the density and viscosity of medium on the frequency change of QCM were discussed, respectively. The QCM result shows that the thickness of the adsorbed PDADMAC layer is 2. 4 nm