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CEO薪酬的影响因素实证分析——基于我国信息行业上市公司的研究 总被引:1,自引:0,他引:1
通过构建多元线性回归模型,以信息行业上市公司为研究对象,考虑可能影响我国上市公司CEO年度薪酬的不同变量,从公司业绩等6个方面描述了影响CEO薪酬的一些因素.研究结果表明:公司业绩、公司规模、地区、年龄及与薪酬之间存在正相关关系;第一大股东的持股比例、两职分离与薪酬之间存在负相关关系;其中对薪酬具有显著影响的变量为公司业绩、公司规模、第一大股东的持股比例. 相似文献
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Using NCEP/NCAR reanalysis data and the sand-storm frequency data fi'om 37 weather stations in the Tarim Basin for the period 1961-2009, the relationship between the frequency of spring sandstorms in the Tafim Basin and the associated atmospheric circu- lation pattems is analyzed in this study. We found significantly negative correlations between sandstorm frequency and the 500-hPa geopotential height over the Paris Basin and midwestem Mongolia, while there were positive correlations over the Ural River region. The rising of the 500-hPa geopotential height in midwestem Mongolia and its falling over the Ural region corre- spond to a weakening of the large-scale wave patterns in the Eurasian region, which directly causes the frequency of the sand-dust storms in the Tarim Basin to decline. Also, the abrupt decline in the spring sandstorm frequency in the Tarim Basin observed in the last half-century is associated with profound changes in the atmospheric circulation in these key regions. At the interannual scale, the strengthened cyclonic atmospheric circulation patterns in the western part of Mongolia and the anticyclonic patterns over the East European plains at 500-hPa geopotential height, are responsible for frequent sandstorm occurrences in the Tarim Basin. 相似文献
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Junhong Bai Qingqing Zhao Junjing Wang Qiongqiong Lu Xiaofei Ye Zhaoqin Gao 《中国地理科学(英文版)》2014,24(3):279-286
Little information is available on denitrification potential of marsh soils in natural saline-alkaline wetlands. The denitrification potentials of an open wetland in the floodplain(Erbaifangzi wetland) and a closed wetland(Fulaowenpao wetland) in backwater areas in Jilin Province of Northeast China were monitored by an anaerobic incubation at 30℃ for 25 days. Our results showed that the relative denitrification index(RDI) increased gradually with incubation time, and showed a rapid increase in the first 5 days of incubation. The RDI values declined quickly from surface soils to subsurface soils and then kept a small change in deeper soils along soil profiles over the incubation time. Denitrification proceeded much faster in the top 20 cm soils of open wetland than in the closed wetland, whereas no significant differences in RDI values were observed in deeper soils between both wetlands. The RDIs were significantly negatively correlated with bulk density and sand content, while a significantly positive correlation with clay content, soil organic matter, total nitrogen and phosphorous. The maximum net NO–3-N loss through denitrification in 1 m depth were higher in the open wetland than the closed wetland with higher soil pH values. Future research should be focused on understanding the influencing mechanisms of soil alkalinity. 相似文献
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The distribution of chlorophyll a and its influencing factors in different regions of the Bering Sea
The distribution of chlorophyll a(Chl a) and its relationships with physical and chemical parameters in different regions of the Bering Sea were discussed in July 2010. The results showed the seawater column Chl a concentrations were 13.41–553.89 mg/m2 and the average value was 118.15 mg/m2 in the study areas. The horizontal distribution of Chl a varied remarkably from basin to shelf in the Bering Sea. The regional order of Chl a concentrations from low to high was basin, slope, outer shelf, inner shelf, and middle shelf. The vertical distribution of Chl a was grouped mainly from single-peak type in basin, slope, outer shelf, and middle shelf, where the deep Chl a maxima(DCM) layer was observed at 25–50 m, 30–35 m, 36–44 m, and 37–47 m, respectively. The vertical distribution of Chl a mainly had three basic patterns: standard single-peak type, surface maximum type, and bottom maximum type in the inner shelf. The analysis also showed that the transportation of ocean currents may control the distribution of Chl a, and the effects were not simple in the basin of the Bering Sea. There was a positive correlation between Chl a and temperature, but no significant correlation between Chl a and nutrients. The Bering Sea slope was an area deeply influenced by slope current. Silicate was the factor that controlled the distribution of Chl a within parts of the water in the slope. Light intensity was an important environmental factor in controlling seawater column Chl a in the shelf, where Chl a was limited by nitrate rather than phosphate within the upper water. Meanwhile, there was a positive relationship between Chl a and salinity. Algal blooms broke out at Sta. B6 of the southwestern St. Lawrence Island and Stas F6 and F11 in the middle of the Bering Strait. 相似文献
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采用有机岩石学一热解分析(ROCK-EVAL)热模拟分析方法对三种典型煤相和镜质组的产烃性质进行了研究.并讨论了产烃性质和有机岩石学参数之间的关系.根据相同煤阶下煤和镜质组的产烃潜量S1 S2值气态烃和液态烃的产率以及湿气含量,得出煤相Ⅰ>煤相Ⅱ>煤相Ⅲ的特点:气态烃和液态烃组成上也有较明显差异.镜质组和煤的产烃潜量.S1 S2值与镜质组的相对荧光强度(I650nm rel%)和光变幅度(Ig/Io)存在明显正相关关系.根据有机岩石学特征和产烃性质.镜质组可分为富氢镜质组和贫氢镜质组两类.在评价煤产烃性质时,必须考虑煤中不同煤相镜质组的还原类型。 相似文献
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Effect of rain enrichment on soil respiration of Nitraria sphaerocarpa community in a hyperarid area
DianJun Liu Bo Wu YongHua Li GuangHui Lin ShiPing Chen YaJuan Zhu Qi Lu Bin Yao 《寒旱区科学》2013,5(6):0722-0732
In order to analyze the effect of rain enrichment on soil respiration rate of a Nitraria sphaerocarpa community, we measured soil respiration rate in bare and vegetated areas in a hyperarid area (Dunhuang) during the growing season. Results show that rain enrichment can increase bare and vegetated soil respiration rates. The more rainfall enrichment, the greater the increment and the longer duration time effect for soil respiration rate. 200% (16 mm) and 300% (24 mm) of rain enrichment can significantly increase bare soil respiration rates by 90% and 106% (P〈0.01), respectively. By contrast, areas with 100% (8 mm), 200% (16 mm) and 300% (24 mm) of rain enrichment can significantly increase shrub area respiration rates by 68%, 157% and 205% (P〈0.01), respectively. The response time of bare and vegetated soil respiration to rainfall enrichment is asynchronous. Response variable of soil respiration in vegetated soil is higher (118%) than in bare soil. There was significant positive correlation between soil respiration rate and soil water content during the growing season (P〈0.01). For every 1 mm increment of precipitation, soil respiration rate increased by 0.01 and 0.04 pmol/(m2.s), respectively in vegetated and bare soils. 相似文献
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Vegetation greenness is a key indicator of terrestrial vegetation activity. To under-stand the variation in vegetation activity in spring across eastern China (EC), we analysed the variation in the Normalised Difference Vegetation Index (NDVI) from April to May during 1982-2006. The regional mean NDVI across EC increased at the rate of 0.02/10yr (r2=0.28; p=0.024) prior to 1998; the increase ceased, and the NDVI dropped to a low level thereafter. However, the processes of variation in the NDVI were different from one region to another. In the North China Plain, a cultivated area, the NDVI increased (0.03/10yr; r2=0.52; p<0.001) from 1982 to 2006. In contrast, the NDVI decreased (-0.02/10yr; r2=0.24; p=0.014) consecu-tively from 1982 to 2006 in the Yangtze River and Pearl River deltas, two regions of rapid urbanisation. In the eastern region of the Inner Mongolian Plateau and the lower reaches of the Yangtze River in East China, the NDVI increased prior to 1998 and decreased thereafter. In the Hulun Buir area and the southern part of the Yangtze River Basin, the NDVI increased prior to 1998 and remained static thereafter. The NDVI in the grasslands and croplands in the semi-humid and semi-arid areas showed a significant positive correlation with precipitation, while the NDVI in the woodlands in the humid to semi-humid areas showed a significant positive correlation with temperature. As much as 60% of the variation in the NDVI was ex-plained by either precipitation or temperature. 相似文献
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深圳湾福田潮滩重金属含量及对大型底栖动物的影响 总被引:9,自引:0,他引:9
根据2002年1月和10月在深圳湾福田潮滩同时获得的大型底栖动物和重金属数据进行分析表明,深圳湾福田潮滩Cu、Pb、Zn、Cd含量明显超标.2002年10月Pb、Cd、Cu、Zn含量的平均值比2002年1月高.与历史资料对比,近几年Cu含量有增加趋势.2002年1月,深圳湾福田潮滩奇异稚齿虫密度与沉积物中Pb、Cd、Cu、Zn含量均有显著负相关关系.尖刺缨虫密度与Pb、Cd、Zn含量均有显著负相关关系,与Cu的相关系数也接近显著相关临界值.2002年10月,只有小头虫密度与Cd有显著正相关关系.文中分析了影响重金属与大型底栖动物数量关系的环境因素. 相似文献