基于高光谱技术的湖泊富营养化综合评价研究——以贵阳市百花湖为例

为了能够准确、快速、大范围地对湖泊富营养化进行监测评价,以贵阳市百花湖为实例,首先,对其水体进行光谱实测与水体采样实验,以及对水体光谱进行归一化、一阶微分、二阶微分等处理,诊断各水质参数的敏感波段,建立其水质参数的高光谱遥感定量模型;其次,探讨湖泊水质高光谱反射率与水质参数浓度之间的定量关系,并采用综合营养状态指数法(TLI)对百花湖富营养化进行评价。结果表明:(1)利用水体光谱的一阶微分反射率分析光谱与水质参数之间的相关性,得出水质参数(Chl-a、TP、TN、SD、CODMn)的敏感波段分别为699nm、823nm、399 nm、563nm、504nm;(2)利用水质参数敏感波段对湖泊水质参数进行估测的效果较为理想,各估测模型R2分别达到0.8276、0.7711、0.7917、0.9213、0.8328;(3)采用水质参数的实测值与估测值对百花湖富营养化评价结果是一致的,且均为中营养化,说明采用高光谱技术对湖泊富营养化的监测与评价是可行的。     

基于分数阶傅里叶变换的水下目标速度估计

在高斯白噪声背景下,匹配滤波器作为线性调频信号的最优检测器,在水声信号处理中被广泛应用。 当发射信号为线性调频信号时,由水下目标径向速度引起的多普勒频移会造成回波和样本之间失配, 使匹配滤波器的检测性能下降,增加了目标速度估计的难度。 利用分数阶傅里叶变换对于线性调频信号的聚焦特性,提出了应用分数阶傅里叶变换的水下运动目标线性调频回波检测算法,完成对目标速度的估计, 推导目标运动速度与分数阶傅里叶变换阶数之间的关系,并对测量结果进行误差分析。 仿真测试表明,该算法可有效地估计混响背景下的目标径向速度,且具有良好的估计性能。     

Application of wireline formation tester in Tarim Oilfield

The application of wireline formation tester(WFT)gradually extends in oil-field with the constant improvement of instrument functions.Applications of WFT in oil and gas exploration in Tarim Oilfield,such as formation pressure measurement,are described,and testing efficiency between drill stem testing(DST)and WFT are compared,especially comprised of PVT sampling,hydrocarbon composition estimation,fluid characterization analysis and formation permeability analysis.The test results between WFT and traditional DST show that their functions can be complementary.The influence factors of WFT and the suitable applying conditions for WFT and DST are also discussed.     

大港南部滩海区沙三段原油地球化学特征及油源分析

大港油田南部滩海区毗邻歧口和歧南两大生烃凹陷,具有双向供烃优势。沙三段是研究区最主要的产油层,但目前对该层段的油源对比结果尚存在争议。为明确油源,分别对原油的族组分、碳同位素、异戊二烯烃和甾萜类化合物等指标的地球化学特征进行分析对比,划分了原油类型。结果表明,南部滩海区沙三段原油可分为三类,第一类原油主要来自沙三段烃源岩,第二类原油主要来自沙一下段烃源岩,第三类原油地化特征介于两者之间,推测其为沙一下段与沙三段烃源岩的混合来源。三类原油在区域上也存在一定的分布规律。     

Multielement analysis of deep-sea sediments by inductively coupled plasma mass spectrometry

Marine sediments were dissolved by HNO3-HF-HCIO4 in a sealed container at low pressure; I-IF was evaporated in an open container and salts were dissolved in HCl by heating, then transferred to 2% HNO3 solution. A total of 45 elements, including Li, Be, So, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Ga, Rb, Sr, Y, Zr, Nb, Mo, Cd, In, Sb, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W, TI, Pb, Bi, Th and U, were measured by inductively coupled plasma mass spectrometry (ICP-MS). Condi-tions and sample experiments showed that this procedure defines a good experimental method which has the advantages of clear interference, easy operation and reliable results. The concentrations of the 45 elements could be used for resource exploration, envi-ronmental assessment and academic research.     

Evolutionary investment network and the emerging energy power in Central Asia: From the perspective of cross-border mergers and acquisitions

Journal of Geographical Sciences - Central Asia is emerging as an important pole of global economic and political power, thanks to its unique location at the heart of Eurasia and its abundance in...     

抚仙湖水温跃层研究

通过自动监测数据(2012-2013),研究了抚仙湖水温跃层的统计规律,给出了温跃层的出现、发展和消失的统计结果,水温跃层一般出现在5月~12月,并且随着时间推移而逐渐下移。与此同时,还分析了温跃层的层次和震动特性,水温跃层一般在40m之上,极少会出现在40m以下,并且会在凌晨出现双层现象,但是不能持久存在,很快就会恢复成单层,在白天温跃层保持单跃层并且比较稳定。该结果有利于提高对于抚仙湖的水体特征认识,加快综合利用湖泊资源的进程。