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于1990年9-12月在青岛海区人工养殖筏采集坛紫菜,提取混合藻胆蛋白,第其经羟基磷灰石柱层析,分离出R-藻红蛋白(RPE)、R-藻蓝蛋白(RPC)和变藻蓝蛋白(APC)。测定了3个不同生长发育阶段的北移坛紫菜中各藻胆蛋白的含量,并与南方坛紫菜做了比较研究。结果表明,坛紫菜生长初期和盛期藻胆蛋白含量较高;到末期大幅度降低,降低的幅度为RPE〉RPC〉APC。各种藻胆蛋白的光谱特性不随藻体的生长发育 相似文献
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城市地理信息系统的功能和内容 总被引:1,自引:1,他引:1
本文论述了城市地理信息系统的主要功能,进而分析了城市地理信息系统的主要内容、模型和界面。 相似文献
5.
The dynamic energy budget (DEB) theory assumes that the feeding of an organism in relation to food density follows the type-II functional response when food consists of purely digestible organic matter. However when faced with a food source high in inorganic content, an organism needs to adapt physiologically to maximise organic extraction. Indeed filter-feeding marine bivalves inhabiting turbid coastal waters cope with large fluctuations in food quality by selectively ingesting and pseudofaeces production. Data from feeding experiments with the New Zealand greenshell mussel Perna canaliculus have demonstrated that inorganic particles contribute some uncertainty to the estimate of the half-saturation coefficient. Incorporating inorganic matter into the functional response would improve the prediction of energy uptake. 相似文献
6.
The structure of the mid- and high-latitude ionosphere during the November 2004 storm event obtained from GPS observations 总被引:1,自引:1,他引:1
Andrzej Krankowski Irk I. Shagimuratov Lubomir W. Baran Galina Yakimova 《Acta Geophysica》2007,55(4):490-508
GPS data from the International GNSS Service (IGS) network were used to study the development of the severe geomagnetic storm
of November 7–12, 2004, in the total electron content (TEC) on a global scale. The TEC maps were produced for analyzing the
storm. For producing the maps over European and North American sectors, GPS measurements from more than 100 stations were
used. The dense network of GPS stations provided TEC measurements with a high temporal and spatial resolution. To present
the temporal and spatial variation of TEC during the storm, differential TEC maps relative to a quiet day (November 6, 2004)
were created.
The features of geomagnetic storm attributed to the complex development of ionospheric storm depend on latitude, longitude
and local time. The positive, as well as negative effects were detected in TEC variations as a consequence of the evolution
of the geomagnetic storm. The maximal effect was registered in the subauroral/auroral ionosphere during substorm activity
in the evening and night period. The latitudinal profiles obtained from TEC maps for Europe gave rise to the storm-time dynamic
of the ionospheric trough, which was detected on November 7 and 9 at latitudes below 50°N. In the report, features of the
response of TEC to the storm for European and North American sectors are analyzed. 相似文献
7.
依据密度测井资料评估煤层的含气量 总被引:1,自引:0,他引:1
煤层甲烷长期以来认为是对采煤工作的危害,只是近十多年来才被认为是一种潜在的能源。煤层不仅是甲烷的储层,而且是甲烷的源岩。煤的物理结构是一种双重孔隙结构,即煤层中含有由基质孔隙和裂缝孔隙组成的孔隙系统。煤层中的气(甲烷)主要吸附在基质孔隙的内表面,是吸附气,而不是存在于骨架粒间的孔隙空间内,因而传统的评价天然气储层含气量的方法虽然不能适合于评估煤层的气含量。本文利用密度测井资料和煤样煤质化验资料确定 相似文献
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云南民族语地名探析 总被引:1,自引:0,他引:1
朱惠荣 《云南地理环境研究》1994,6(1):11-22
云南有25种世居的少数民族,是全国少数民族最多的省,也是民族语地名语种最多的省。云南被称为“地名博物馆,,民族语地名有其典型性。云南的民族语地名有很多特点,但并不特殊,在其他地方也似曾相识。本文以一个省为单元,对少数民族语地名进行全面综合研究,探讨民族语地名与地理环境、历史发展的关系及各种民族语地名之间的关系。 相似文献
9.
Climate change poses a challenge to countries across the world, with news media being an important source of information on the issue. To understand how and how much news media cover climate change, this study compares coverage in ten countries from the Global North and the Global South between 2006 and 2018 (N = 71,674). Based on a panel analysis, we illustrate that news media attention varies across countries and is often associated with political, scientific, and (partly) societal focusing events. Based on an automated content analysis, we also find that news media do not only cover ecological changes or climate science, but that they focus predominantly on the societal dimension of climate change: They emphasize how humans are aware of, affected by, battle, or cause climate change. Overall, the study illustrates important differences between the Global North and the Global South. While countries from the Global North cover climate change more frequently, countries from the Global South focus more on its challenges and implications for society at large, i.e., the societal dimension of climate change. 相似文献
10.
陈志清 《云南地理环境研究》1991,3(2):23-33
本文对采自中国、法国、比利时等国43块黄土样品进行实验室处理后,分析对比了它们在碳酸盐含量、粒度组成、重矿物组成及粘土矿物成分方面的共同特性及差异性。结果表明,中国黄土碳酸盐含量稳定,西欧不同类型的黄土碳酸盐含量差别很大。在粒度组成上,欧亚黄土并没有本质的差别,但西欧不同层位的黄土粒度组成呈有规律变化。对西欧重矿物的分析可以追溯黄土的物质来源,粘土矿物含量在欧亚不同黄土中也有差别。比较结果说明,欧洲的黄土堆积受第四纪冰期、间冰期的气候波动影响较大,中国黄土在堆积期间始终处在干旱、半干旱的气候条件下。 相似文献