城市三维绿色空间指标“绿强度”研究——以青岛西海岸新区中央活力区为例

针对城市垂直化发展趋势以及城市居民对多维绿色生活空间的需求,提出城市三维绿色空间指标“绿强度”的概念和意义,并以青岛西海岸新区中央活力区为例,探讨了“绿强度”的计算方法、规划分区和实施机制,为高密度城市三维绿色空间系统的规划和管理提供参考。

有腹筋简支开洞深梁承受集中力时的抗剪设计

分析了洞口大小、位置及腹筋形式、配筋量对简支开洞深梁承受集中力时剪切性能的影响，按洞口形态将开洞深梁划分为整体计算及洞口上下分别计算再叠加两类，并提出了相应的剪切强度计算公式。

ZnO荧光薄膜的制备及特性研究

采用直流反应磁控溅射方法在镀有ITO的玻璃衬底上制备了ZnO荧光薄膜 .通过X射线衍射 (XRD)、能谱分析仪对退火前后薄膜的结晶状况和成分进行了分析 ,利用荧光探测单色仪对薄膜的光致发光 (PL)特性进行了研究 .退火前后的发光峰分别位于光谱绿区 4 99 2nm和 5 17 8nm处 .退火处理明显提高了绿光强度 。

YbF_(3):Er荧光粉的固相制备及多波长响应上转换性能

采用固相法制备了Er3+掺杂的YbF3固溶体荧光粉,通过XRD、SEM、PL对样品进行了表征。结果表明:400℃烧结即可获得正交晶相的YbF3荧光粉,提高烧结温度,粉粒由片状变为球状并增大,发光增强,随着Er3+掺杂量的提高,样品上转换发光强度先增后降,掺杂量为16%时发光最强。通过3种波长激光泵浦发现,样品的上转换发光峰分别位于410、525、541、550、660 nm(671 nm),样品的发光性能差异大,其发光强度I_(vis,980 nm)>>I_(vis,1550 nm)>>I_(vis,1064 nm),红绿光强度比RGR_(1064 nm)>RGR_(980 nm)>>RGR_(1550 nm)。980 nm和1064 nm激光泵浦所得发光的CIE色坐标位于橙色区,而1550 nm激光泵浦所得发光的CIE色坐标位于黄绿色区。通过上转换机制,对比分析了多种波长激光泵浦下样品发光性能差异的原因。

Combined effects of light intensity and NH_4^+-enrichment on growth, pigmentation, and photosynthetic performance of Ulva prolifera(Chlorophyta)

The aim of this study was to investigate the effects of light intensity and enhanced nitrogen supply on the growth and photosynthesis of the green-tide macroalga, Ulvaprolifera. Thalli of U. prolifera were grown in natural or NH^-enriched seawater under two different light intensities for 7 days, and then the growth rate, pigmentation, and photosynthetic performance of the thalli were evaluated. The results show that the relative growth rate （RGR） was markedly higher under the high light level than under the low light level. Enrichment with NH~ enhanced the RGR under high light intensity, but did not affect RGR under low light intensity. In low light conditions, NH;-enrichment resulted in a marked decrease in the maximal photosynthetic rate （Pro） and the maximum carbon fixation rate （Vmax）, but it did not affect the half saturation constant for carbon （K0.5） or the ratio of Vmax to K0.5, which reflects the carbon acquisition efficiency. In high light conditions, Pm, K05, and the dark respiration rate （Rd） increased under NHI enrichment, but Vmax and the Vmax/Ko5 ratio decreased. Regardless of the light intensity, NH^＋4-enrichment did not affect the apparent photosynthetic efficiency （a）, which reflects the ability of the alga to use light energy at low light levels. Under both low and high light intensities, the chlorophyll a （Chl a）, chlorophyll b （Chl b）, and carotenoids （Car） contents in thalli were higher in NH1-enriched than in natural seawater, except that there was a decrease in the Chl b content of thalli in NH1-enriched seawater under low light intensity. Therefore, NH^＋4 enrichment improved the growth and photosynthetic performance of U. prolifera under high light intensity, but not under low light intensity. We discuss the possible mechanisms underlying these physiological responses.