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91.
利用静态箱-气相色谱法对泥河水库春季水-气界面二氧化碳通量值进行连续24h观测,对其变化趋势及影响因素加以分析。结果表明:泥河水库24h均为大气CO2的源,其碳通量均值为26.50mg/(m2·h),全天源的极大值出现在1∶00为32.38mg/(m2·h),源的极小值出现在13∶00为20.15mg/(m2·h)。在春季影响泥河水库水-气界面CO2通量变化的主要因素是气温、叶绿素和风速,相关系数分别为0.671、0.625、0.253。结论:水库水-气界面CO2通量的变化是多种因素共同作用的结果,春季水库是大气CO2主要碳源之一。 相似文献
92.
同一震源区两次地震到达某台站的直达P波、S波零频观测谱值之比与其辐射图型因子之比线性相关,而后者取决于震源机制的几何特性。用波形记录计算谱振幅相关系数,认为该系数是震源机制异同的归一化数值描述。据此对2003年青岛序列及冀鲁豫交界地区小震集中区地震事件进行聚类分组,给出序列事件的滑动平均相关系数的时序曲线。研究结果表明:青岛序列的滑动平均相关系数时序曲线存在由一致到发散的变化过程,即震源区应力场强度由相对集中向逐步分散过度;冀鲁豫交界地区小震集中区谱振幅相关系数较低,震源机制各不相同,区域应力积累没有形成任何一个优势方向。 相似文献
93.
The correlation of geological records is commonly based on subjective and arbitrary interpretation by a researcher. Geological data are usually collected as a series on a depth scale, and then chronologies of the profiles are constructed. The correlation of geological records based on matching quality indicators requires an efficient method of searching for the best position. GenCorr is a software based on a genetic algorithm, for correlation of records with or without accompanying chronological control. Where their age information is available, points on both records may be moved in the range limited by the age uncertainties. GenCorr has been developed by the authors in Borland RAD Studio 2007 environment. The authors tested the impact of matched record length, noise level, sampling resolution, or additional linear components and hiatuses on the correlation results using artificial test data. Finally, the genetic algorithm was applied to stable isotope records obtained from two stalagmites collected from the Demianova Cave System (Low Tatras, Slovakia). The results show that the genetic algorithm correlation method is similar to that used in pattern recognition by the human eye without prior knowledge of the ages. The genetic algorithm is able to correlate in multidimensional space and is free from human biases, but we accept that there are also occasions where additional expert opinion may be also important. GenCorr can be run on every PC with MS Windows operating system, the package was not tested in Mac environment. GenCorr is available as a freeware from the authors. For downloading, please contact: dzeq@twarda.pan.pl. 相似文献
94.
细颗粒物（PM2.5）即粒径小于2.5μm的可吸入颗粒物[1],是当今中国城市大气污染的首要污染物。本研究以北京市为例,选取北京市2010年至2012年三年内采暖期与非采暖期两个不同时期的细颗粒物（PM0.3,PM0.5,PM1）实测数据,及同时期北京市患呼吸系统疾病人数数据,运用地统计的空间分析方法,对获取数据进行空间化及插值研究。通过偏相关分析法对北京市细颗粒物浓度与患呼吸系统疾病人数数据进行相关分析。得出以下主要结论：①细颗粒物的空间变化明显,2010年、2011年及2012年细颗粒物浓度整体呈上升趋势,2012年三种粒径细颗粒物浓度整体高于2010年与2011年。②不同粒径的细颗粒物,对呼吸疾病的影响程度不同：在0.3μm,0.5μm与1μm三种粒径的细颗粒物中,PM1对呼吸系统疾病影响最大,偏相关系数达到0.785。 相似文献
95.
腾冲火山岩年龄问题评述 总被引：1，自引：0，他引：1
腾冲火山及火山岩是国内新近纪火山及其喷发物九大分布区之一,研究程度较广较深,喷发序列岩石定岩及年龄值资料丰富,综合评述并指出今后研究方向。 相似文献
96.
97.
In this study, it was aimed to characterize temporal variations of air pollutants for determining contribution to pollution episodes and to obtain correlations between these pollutants. With this aim we used data analysis for measured sulfur dioxide (SO2), particulate matter (PM, black fume and PM10), nitrogen oxides (NOx), ozone (O3), carbon monoxide (CO), methane (CH4), and non‐methane hydrocarbons (NMHC) recorded in Kocaeli, one of the most industrilizated cities of Turkey. Pollutant concentrations were the results of continuous and semi‐automatic measurements. Semi‐automatic measurements of SO2 and PM (black fume) were enclosing period from 1987 to 2008 whereas continuous monitoring of all pollutants included years of 2007–2009. In the first stage of the study daily, monthly, annual, and seasonal variations of pollution were researched. Annual average concentrations were compared with limits set by Air Quality Protection Regulation (AQPR), Air Quality Evaluation and Management Regulation (AQEMR), World Health Organization (WHO), European Union (EU), and National Ambient Air Quality Standards (USEPA). In the following stage relationships between pollutants such as NO2–O3, NOx–CO, NOx–NMHC, and NOx–SO2 were investigated and correlation coefficients were determined as 0.87, 0.56, 0.51, and 0.69, respectively. R2 values of regression models developed from these correlations were 0.78, 0.56, 0.34, and 0.72, respectively. Vehicle density of the traffic was evaluated with NOx–O3 emissions and decrease was seen in NOx emissions due to decreasing vehicle density at weekends whereas O3 concentrations increased. These correlations enable prediction of the parameters that cannot be measured which is important for providing improvement in early warning systems. 相似文献
98.
99.
The geothermal waters of the first and the shallowest groundwater system of the Province of Vojvodina in northern Serbia, south part of the Pannonian Basin, are characterized by elevated temperatures (between 25 and 85 °C) and elevated gas content (above 1 Nm3/m3) with a high methane content (average about 94% of total gases). These methane-containing waters are particularly abundant in the Central part of the province between Danube and Tisa rivers. Dominant ions in these waters are sodium and bicarbonate, but the waters also contain significant amounts of calcium, magnesium, potassium, chloride, and ammonium. Components that are of balneological significance include iodine, bromine, fluorine, strontium, lithium, barium, and metasilicic and metaboric acids. Based on statistical analysis, a strong positive correlation is generally observed in about 9.2% cases. A slightly lower correlation appears in about 42.2%, and negative correlation coefficient appears in about 48.6% cases. The dendrogram of the cluster analysis built on the wells shows three main groups. There is the cluster of (Na+)aq, (Cl−)aq and (HCO3−)aq. The second aggregation is (NH4+)aq/(NH3)aq. The third group includes (Mg2+)aq, (Ca2+)aq, (Fe3+)aq, (Sr2+)aq, (Pb2+)aq, and (Zn2+)aq. 相似文献
100.