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幼鲍初期饵料生物在玻片上着生物量的消长与光强度的关系进行了试验,光强度超过2500Lu时微生物膜增长较快,膜脱落较早;光强度低于1000Lux时微生物膜净生产量较低,光强度在1500-2000Lux时有利于膜生物量的积累,舟形藻和菱形藻的纯培养在玻片上附着的生物量呈稳定性高速增长并能延迟生物膜脱落现象的发生。 相似文献
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The effect of light intensity ( 1500 Ix and 5000 Ix) on the total lipid and fatty acid composition of six strains of marine diatoms Cylindrotheca fusiformis (B211 ), Phaeodactylum tricornutum (Bl14, Bl18 and B221) Nitzschia closterium (B222) and Chaetoceros gracilis (B13) was investigated.The total lipids of B13, Bl14, and B211 grown at 5000 Ix were lower than those grown at 1500 Ix. No evident changes were observed in Bl18, B221 and B222. Fatty acid composition changed considerably at different light intensity although no consistent correlation between the relative proportion of a single FA and light intensity. The major fatty acids of the 6 strains were 14:0, 16:0, 16:l(n- 7) and 20:5(n-3) . Cylindrothecafusiformis had high percentage of 20:4n - 6 (9.2 - 10.9% ) . The total polyunsaturated fatty acid /rl all 6 strains decreased with increasing light intensity. The percentage of the highly unsaturated fatty acid eicosapentaenoic acid (EPA) decreased with increasing light intensity in all strains except Chaetoceros gracilis. 相似文献
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本文描述了11个铀酰矿物加热后的显微荧光特征,并对实验结果进行了初步探讨。随着温度的升高,其相对荧光强度均有不同程度的衰减直至猝灭,但衰减的速度和猝灭的温度是各不相同的。热至200℃时测量的荧光光谱和常温下的荧光光谱相比,不同矿物变化也各不相同。本文根据实验结果绘制了荧光和温度关系曲线及加热至200℃时的荧光光谱曲线。这种荧光变化可能与加热后矿物失水和晶体结构变化有关。对鉴定铀酰矿物具有重要的意义。 相似文献
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极光是日地能量耦合过程中粒子沉降到极区电离层的最直观表现,对于理解地球空间环境及预测空间天气具有重要作用.本文利用2003-2009年的北极黄河站的多波段地面极光观测,结合DMSP卫星粒子沉降探测,对磁正午附近的极光强度与沉降粒子沉降能量之间的关系进行了定量研究.统计结果表明,在10-13磁地方时(MLT)630.0 nm的极光发光占主导,以低能粒子沉降为主;而在13-14MLT,630.0 nm/427.8 nm极光强度比值降低,沉降粒子能量较高.另外,利用极光强度与沉降电子的能通量以及极光强度比值与平均能量之间的函数关系,初步建立了北极黄河站磁正午附近极光强度与沉降粒子能量关系的反演参数模型,为将来空间天气的监测服务. 相似文献
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基于激光扫描回光强度的建筑物立面信息提取与分类 总被引:3,自引:0,他引:3
针对车载三维测量系统中的激光扫描仪回光强度值,提出了一种基于强度值的地物信息提取和分类方法.将回光强度值进行角度、距离统一改正,并分级显示,通过绘制地物在不同能量级上的分布曲线,确定曲线峰值对应的强度级.实验结果表明,区分不同地物分布曲线上的峰值可以实现地物的提取和分类. 相似文献
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胶州湾海水黄色物质荧光分布初步研究 总被引:14,自引:1,他引:14
研究海水黄色物质,在实验室研究的基础上,于1999年9月1-2日,利用荧光测量法,现场测量了胶州湾黄色物质荧光相对强度,首次获得了我国海区黄色物质分布数据。胶州湾黄色物质荧光强度主要分布特征为:胶州湾黄色物质荧光强度高度区分布在沿岸,尤其在河口附近;湾口次之;湾中部区域再次之,湾口外侧最小;胶州湾黄色物质垂直分布不均匀。这种分布与胶州湾的自然环境密切相关,尤其与沿岸径流有关,因此,初步认定胶州湾黄色物质为陆源物质,由沿岸径流携带入海湾。 相似文献
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以内蒙古东南部白音罕山落叶松样芯为研究对象,建立研究区124年(1895—2018年)树木年轮晚材蓝光强度差值年表.通过选取年表(1895—1998年)与气象因子的响应分析发现:落叶松晚材蓝光强度年表与6—8月的温度(r=0.42,P<0.01)存在显著的正相关,与6—8月的降水(r=-0.39,P<0.05)和7—1... 相似文献
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COMBINED EFFECTS OF TEMPERATURE, IRRADIANCE AND SALINITY ON GROWTH OF DIATOM SKELETONEMA COSTATUM 总被引:2,自引:0,他引:2
3-factor experiment was used to study the combined effects of temperature, irradiance and salinity on the growth of an HAB
species diatomSkeletonema costatum (Grev.) Cleve. The results showed that temperature (12, 19, 25, 32 °C), irradiance (0.02, 0.08, 0.3, 1.6)×1016 quanta/(s·cm2)) and salinity (10, 18, 25, 30, 35) significantly influenced the growth of this species. There were interactive effects between
any two of and among all three physical factors on the growth. In the experiment, the most optimal growth condition forS. costatum was temperature of 25°C, salinity of 18–35 and irradiance of 1.6×1016 quanta/(s·cm2). The results indicatedS. costatum could divide at higher rate and were more likely to bloom under high temperature and high illumination from spring to fall.
It was able to distribute widely in ocean and estuary due to its adaptation to a wide range of salinities.
This study was supported by the PREPP and National Key Basic Research Project (2001CB4097) NNSFC No. 39950001, 20177023, 49576301,
49906007 and KZCX2-206. 相似文献