不同生长发育期土壤绿藻——集球藻细胞形态结构研究

集球藻是一种广泛分布于生物结皮中的土壤绿藻,能够积累红色素(如虾青素)和油滴,显示出其独特的生理特性和潜在的应用价值.目前对集球藻的细胞结构以及色素积累研究非常匮乏.本文报道应用光学显微镜和透射电境观察集球藻在温室液体培养条件下,细胞形态与超微结构变化.结果表明,培养早期时营养细胞转变为生殖细胞,并通过细胞分裂产生子代...     

基于GSM通讯网络的污水余氯检测及排放系统的研究

介绍了基于GSM通讯网络的污水余氯检测及排放系统的设计原理和实现方法,采用测量透射光强的电信号来确定样品中余氯含量,以检验污水氯化消毒处理是否满足国家排放标准要求。系统具有在线连续检测、自动排放及数据远传通讯、报表查询等功能。克服了目前国内医疗污水检测处理方法的不足,在污水处理领域具有广阔的应用前景。     

Comparison of the Photosynthetic Characteristics of Two Developmental Stages in Nostoc sphaeroides Kutzing （Cyanophyta）

The photosynthetic activities between two main developmental stages, colony and hormogonium, of the edible cyanobacterium Nostoc sphaeroides Kutzing, were compared. Hormogonia have a higher content of chlorophyll than that of colonies. It showed that the ratios of phycocyain （PC）, allophycocyain （APC） and phycoerythrocyanin （PEC） in hormogonia and colonies were different. The room temperature chlorophyll fluorescence, 77 K chlorophyll fluorescence, measurements of PSⅠand PS Ⅱ activities all showed that colony has higher photosynthetic competence than hormogonia. Hormogonia had a higher respiration rate than colony, while their maximum photosynthetic oxygen evolution rates were very close. The responses of hormogonia and colonies to high light illuminations also were different. Both of their oxygen evolution rates decreased quickly with the prolonged high light illumination, but hormogonia can keep relatively higher PSⅡ activity （Fv/Fm） than that of colonies. The results suggested that colony was photosynthetically more competent than hormogonia, while the ability of hormogonia to tolerate high light illumination was higher than that of colony.     

基于BP神经网络考查课评分系统

考查课在大学课程中占有很大的比例，而其成绩的评定易受教师主观因素影响，不够准确。利用具有自学习、自识别能力的BP神经网络建立考查课考评体系，不断调整网络的权值使SSE（平方误差和）总朝着减小的方向发展，直到达到目标误差为止。