6 resultados para Zappa, Frank, 1940-1993

em Chinese Academy of Sciences Institutional Repositories Grid Portal


Relevância:

20.00% 20.00%

Publicador:

Resumo:

溪河大尾溞LeydigiaflumineaChen,1993(甲壳纲:双甲目)雄体的发现陈受忠,唐文乔,刘焕章中国科学院水生生物研究所武汉430072枝角类(Cladocera)的繁殖方式以孤雌生殖为主,雄性只在一定季节或特种条件下短期出现。而且还有...

Relevância:

20.00% 20.00%

Publicador:

Resumo:

<正> 固氮蓝藻是一类低等原核植物。它能进行固氮作用,固定空气中分子态氮成为氮素化合物;又能进行光合作用,将二氧化碳变为碳素化合物并放出氧气,为自身的固氮提供能源和还原剂。由于具有以上功能,它们适应性很强往往是贫瘠土壤的先驱植物,因此,很早就引起了人们的重视。早在1889年Frank首先发现生长着蓝藻的土壤在光照下,氮化合物的含量有所增加;1901年Beijerinck发现在仅有一点土壤的缺氮水中的小链鱼腥藻

Relevância:

20.00% 20.00%

Publicador:

Resumo:

基于能量最小近似模型,研究了应变异质结外延材料中,产生Frank-Read源以释放失配应力所需GeSi合金缓冲层的厚度。对Ge_xSi_(1-x)/Si进行了具体计算,其结果表明:产生Frank-Read源时缓冲层厚度要比临界厚度大得多,L_(min)=1300A是钉扎点间的最小距离。计算结果与LeGoues等的实验结果相符。就作者所知,计算产生Frank-Read源时GeSi合金缓冲层厚度的工作,以前未见报道。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A three-dimensional (3-D) coupled physical and biological model was used to investigate the physical processes and their influence on the ecosystem dynamics of the Bohai Sea of China. The physical processes include M-2 tide, time - varying wind forcing and river discharge. Wind records from I to 31 May in 1993 were selected to force the model. The biological model is based on a simple, nitrate and phosphate limited, lower trophic food web system. The simulated results showed that variation of residual currents forced by M, tide, river discharge and time-varying wind had great impact on the distribution of phytoplankton biomass in the Laizhou Bay. High phytoplankton biomass appeared in the upwelling region. Numerical experiments based on the barotropic model and baroclinic model with no wind and water discharge were also conducted. Differences in the results by the baroclinic model and the barotropic model were significant: more patches appeared in the baroclinic model comparing with the barotropic model. And in the baroclinic model, the subsurface maximum phytoplankton biomass patches formed in the stratified water.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

对青海钩虾的营养价值进行了初步的研究。首先分析三种不同品级的青海钩虾,一般营养成分及氨基酸含量,并同两种鱼粉比较;第二,养鸡试验的结果表明,钩虾组在平均增量和总增重量等方面都优于鱼粉;第三,真鲷Pagrosomusmajor(Temminck&Schlegel)的实验是按照逐次降低钩虾的含量的方法,分为4组。Ⅰ.钩虾:鱼粉=6:4,Ⅱ.钧虾:鱼粉=4:6,Ⅲ.钩虾:鱼粉=2:8,Ⅳ.钩虾:鱼粉=0:10。实验结果显示在其鲷的成活率、体长平均增长率、增重率和饲料系数等方面,含钩虾组较无钩虾(Ⅳ)为佳,而Ⅱ组具有最好的促增重效果和最经济的特点。最后,根据上述分析和实验结果,作者认为青海钩虾是一种可以代替鱼粉的新蛋白源,值得开发利用和推广。