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281.
厦门地震台数字化仪器零点台阶产生原因探讨   总被引:6,自引:1,他引:5  
自使用数字化仪器观测以来,厦门地震台多套仪器的记录曲线均出现台阶现象,大部分出现在当日数据之间。也有一种台阶非常特殊,它出现在当日00h00m数据和昨日23h59m数据之间,称为“零点台阶”。本文对台阶产生的原因简单分析,重点对零点台阶出现的时间进行统计,试图寻找这种台阶的产生规律,讨论出现的可能原因。  相似文献   
282.
在野外调查和考察工作的基础上,通过对所获实验数据的综合分析并参考有关资料,研究了厦门海沧经济开发区的地质环境特征与环境地质条件。结果表明,该区原生地质环境良好,确系海内外投资者不可多得的施展鸿图的理想之地。  相似文献   
283.
贺辉扬 《台湾海峡》1998,17(3):317-323
火烧屿理厦门西港中一个较大的岛屿,自然旅游资源丰富,环境质量良好,具有特定的旅游开发利用价值。本文在其旅游资源特点和开发条件分析评价的基础上,提出了开发民建议。  相似文献   
284.
利用分层分类法进行厦门岛城市地表分类研究   总被引:1,自引:0,他引:1  
本文利用分层分类法把厦门岛城市地表分为七类,并对分类结果进行了验证。在TM图像光谱特征分析和归一化差异型指数分析结论上,提出分层分类法的分类步骤。利用ERDAS的专家分类器逐类地提取地表类型,并利用掩膜法将原图像上新提取地类所对应区域掩膜掉,使得分类过程越来越容易。分层分类法避免了一次划分多种类别方法,在选择波段组合上的矛盾。精度评价结果表明,总分类精度90.9%,达到分类要求标准。  相似文献   
285.
The European shore-crab Carcinus maenas has been present in South Africa since 1983. Despite this species’ international reputation as a biological invader, its distribution in this region has only been considered by three outdated ‘snapshot surveys.’ The present study is the most comprehensive to date, providing an update on the species’ range and the first temporal assessment of its abundance and demographics. Along South Africa's Cape Peninsula and surrounding areas, C. maenas was absent from 12 intertidal sites surveyed, except for Sea Point, and no crabs were found during subtidal surveys along the open coastline. Subtidal harbour populations were recorded in the Cape Town harbours of Table Bay and Hout Bay (previously estimated as comprising approximately 164 200 and 6 500 individuals, respectively). Table Bay was surveyed monthly for one year, using baited traps, crab condos and postlarvae settlement collectors, to assess size distributions and reproductive seasonality of the crab. Reproductive females were recorded throughout most of the year. These results suggest that the harbour populations could be targeted by control programmes, but provide no strong evidence to support the initiation of management action during a particular season. The lack of detection of postlarval settlement, even among well-established populations, suggests this will not be a useful monitoring tool for detecting incursions.  相似文献   
286.
根据传统形态学分类方法,对2015年5~11月厦门白哈礁海域进行的珊瑚资源调查所采集到的8个石珊瑚样本进行了初步分类鉴定.通过对比鉴定文献和图集,结果显示:厦门白哈礁海域分布的石珊瑚有6种,分别是筒星珊瑚属的猩红筒星珊瑚(Tubastraea coccinea)、Tubastraea tagusensis和筒星珊瑚属未知种(Tubastraea sp.)以及木珊瑚属的未知种(Dendrophyllia sp.),木珊瑚科2个未知种(Dendrophylliidae sp.1、Dendrophylliidae sp.2).同历史文献对比显示,除了猩红筒星珊瑚外,其余5种都是厦门发现的新记录种.  相似文献   
287.
本文立足厦门市"汽车-工程机械"产业企业的发展实际,对影响龙头企业技术创新的经济因素和非经济因素进行调查和分析,其中经济因素包括企业R&D投入、科技人才资源、产学研合作和专利品牌建设;非经济因素包括企业制度管理、企业文化氛围和政府政策行为。在此基础上,以厦工重工为案例进行综合分析,提出提高龙头企业技术创新能力的相关政策建议。  相似文献   
288.
Xiamen is an important coastal harbour and tourist city. Since the establishment of the Xiamen Special Economic Zone in 1980, great changes of developments in economy and urban construction have taken place. The comprehensive development is most important to Xiamen's future. Xiamen has favorable geographical location, high level of economy opening to the outside world and close relation with Xiamen-Zhangzhou-Guanzhou economic area. The Xiamen Special Economic Zone should play the role of central city in the south Fujian Province.  相似文献   
289.
Organochlorine contaminants including 12 polychlorinated biphenyl (PCB) congeners and 18 insecticides were determined in water, pore water and sediments of the Jiulong River Estuary and Western Xiamen Sea, China. The results showed that the levels of the total PCBs ranged from non-detectable to 1500 ng l−1 in water, from 209 to 3870 ng l−1 in pore water, and from 2.78 to 14.8 ng g−1 dry weight in sediments. Total organochlorine insecticide concentrations were from below the limit of detection to 2480 ng l−1 in water, from 267 to 33400 ng l−1 in pore water, and from 4.22 to 46.3 ng g−1 dry weight in sediments. Concentrations of PCBs and insecticides in pore water were significantly higher than those in surface water, due to the high affinity of these hydrophobic compounds for sediment phase. The PCB congeners with the highest concentrations were CB153, CB180 and CB194, which together accounted for 68–87% of total PCBs in water, pore water and sediment. Among the hexachlorocyclohexane (HCH) compounds, beta-HCH was found to be a major isomer. Analysis of 1,1,1-trichloro-2,2-bis-chlorophenyl-ethane (DDT) and its metabolites showed that 1,1-dichloro-2[o-chlorophenyl]-2[p-chlorophenyl]-ethylene (DDE) was dominant in the group. In comparison to a 1998 study in the Western Xiamen Sea, levels of organochlorines were enhanced due probably to recent inputs and changes in sediments.  相似文献   
290.
KINETICS OF LEAD ADSORPTION BY XIAMEN BAY SEDIMENTS   总被引:1,自引:0,他引:1  
The kinetics of Pb adsorption in seawater by surface sediments from Xiamen Bay was simulated and the effects of seawater conditions were studied . When water temperature changed from 20 to 30℃, pH from 5 to 8 and salinity from 30 to 4 . the adsorption rate increased by about 50% , one order of magnitude and 5 times, respectively . A negative exponential relation between the adsorption rate and salinity has been found . The adsorption processes can be simulated by the exchange- equilibrium kinetic model . Adsorption rate constant, apparent activation energy and equilibrium adsorptive capacity have been quantitatively determined . The adsorption of Pb by sediments is essentially a chemical action .  相似文献   
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