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101.
东海陆架盆地位于欧亚板块的东南缘和西太平洋活动大陆边缘,本文选取了东海陆架盆地主要凹陷的17条地震剖面,采用平衡剖面技术,计算了主要凹陷新生代不同演化阶段的伸展率和压缩率。分析表明,东海陆架盆地构造演化总体由西向东跃迁。晚白垩世至晚古新世东海陆架盆地裂陷中心在西部坳陷带,始新世东迁至东部坳陷带,上新世东迁至东海陆架盆地东侧的冲绳海槽盆地。古新世中后期东海陆架盆地西部坳陷带北侧昆山凹陷反转;中新世东部坳陷带的西湖凹陷反转。东海陆架盆地西部坳陷带与东部坳陷带构造演化不同,证明了东海陆架盆地的东西分带。西部坳陷带北部的长江坳陷和南部的台北坳陷构造演化不同,东部坳陷带北部的西湖凹陷和南部的钓北凹陷构造演化不同,证明了东海陆架盆地的南北分块。 相似文献
102.
测量不确定度作为当今矿石主要的评定方式,其评定是表征并赋予测量结果的分散性,为最终的测量结果附带参数,以此来客观衡量测量量的分散性。根据数值的特点分为两个度量,符合统计规律的数值,称为A类不确定度;不符合统计规律的数值称为B类不确定度。将不确定度的评定方法运用到铜精粉中铜含量的测定中,最终得出样品铜精粉中19.94%~20.34%的铜含量,同时对铜精粉中铜的测量实验及实验结果不确定度的评定进行了系统的研究,并将整个实验及结果不确定度的计算过程简述,这样不仅达到了测量的目的,还能对不确定度进一步认识,也给冶炼工业的发展提供了可参考的研究方法。 相似文献
103.
Spatio-temporal trends of heavy metals and source apportionment in Tolo Harbour,Hong Kong 总被引:1,自引:1,他引:0
This study provided a picture of the spatial and temporal distributions of Cr, Co, Ni Cu, Zn, As, Cd and Pb in bottom sediments
of Tolo Harbour. The concentrations of the eight heavy metals differed significantly between sites due to the poor tidal flushing
in Tolo Harbour. The levels of Cu, Zn, Cd and Pb were generally enriched in sediments from inner Tolo Harbour, while sediments
from outer Tolo Harbour (Tolo Channel) had higher levels of Cr, Co and Ni. The redox sensitive element arsenic showed no distinct
spatial pattern in Tolo Harbour. The decreasing levels of Cu, Zn, Pb and Cd in sediments with increasing distance from land
demonstrated a typical diffusion pattern from land to the direction of sea. Two hot spots of Cu, Zn, Pb and Cd in sediments
were located near Tai Po and Sha Tin new town, indicating that Cu, Zn, Pb and Zn were from land-derived sources. The sites
with relatively high levels of Cr, Co and Ni in sediments were located in areas close to waste spoil in sea floor. The natural
and anthropogenic inputs from Sha Tin and Tai Po to Tolo Harbour were mostly responsible for Cu, Zn, Cd and Pb enrichment
in sediments from inner Tolo Harbour. The waste spoil in sea floor was believed to contribute to the Cr, Co and Ni in outer
Tolo Harbour. The results of correlation coefficient between the eight heavy metals showed that Cu, Zn, Cd and Pb were strongly
positively correlated, and Cr, Co and Ni were also significantly correlated with each other. The best explanation of strong
correlation was their similar source. As, however, is not well correlated with the other seven heavy metals. The average concentrations
of Cu and Zn displayed general increasing trends from 1978 to 2006 in Tolo Harbour, while the mean levels of Cr and Pb displayed
a substantial decrease from 1978 to 1987, then a slight increase after 1987. No distinct temporal trends of the concentrations
of Ni and As were observed from 1978 due to the inconsecutive data. On the other hand, the increasing trends of Cr, Cu, Zn,
Cd and Pb were observed since 1996. 相似文献
104.
For the offshore wind turbines installed in earthquake areas, their operation is affected by seismic loads in addition to wind and wave loads. Therefore, it is necessary to study the dynamic responses and vibration control of the wind turbines. In previous studies, the structural responses of offshore wind turbines are usually investigated in the parked case, while the blade rotation effect is usually not considered. The evaluation on the structural responses may be inaccurate under this conditi... 相似文献
105.
Yuexin Ma Feixue Sun Congyao Zhang Pengyun Bao Shuqing Cao Meiyan Zhang 《中国海洋大学学报(英文版)》2014,13(6):1061-1066
A marine bacterium, Pseudoalteromonas sp. BC228 was supplemented to feed in a feeding experiment aiming to determine its ability of enhancing the digestive enzyme activity and immune response of juvenile Apostichopus japonicus. Sea cucumber individuals were fed with the diets containing 0(control), 105, 107 and 109 CFU g-1 diet of BC228 for 45 days. Results showed that intestinal trypsin and lipase activities were significantly enhanced by 107 and 109 CFU g-1 diet of BC228 in comparison with control(P 0.01). The phagocytic activity in the coelomocytes of sea cucumber fed the diet supplemented with 107 CFU g-1 diet of BC228 was significantly higher than that of those fed control diet(P 0.05). In addition, 105 and 107 CFU g-1 diet of BC228 significantly enhanced lysozyme and phenoloxidase activities in the coelomic fluid of sea cucumber, respectively, in comparison with other diets(P 0.01). Sea cucumbers, 10 each diet, were challenged with Vibrio splendidus NB13 after 45 days of feeding. It was found that the cumulative incidence and mortality of sea cucumber fed with BC228 containing diets were lower than those of animals fed control diet. Our findings evidenced that BC228 supplemented in diets improved the digestive enzyme activity of juvenile sea cucumber, stimulated its immune response and enhanced its resistance to the infection of V. splendidus. 相似文献
106.
HY-2是中国自主研发的海洋卫星。 本文研究了利用HY-2卫星扫描微波辐射计亮温数据反演北极海冰密集度的方法。参考NASA TEAM方法,我们对典型海区光谱梯度率和极化梯度率进行了统计分析,确定了计算海冰密集度所需的亮温特征值;利用天气滤波器有效去除了开阔海域由于大气中水蒸气、云中液态水、降雨等现象引起的海冰密集度计算错误。本文计算了2012年全年的北极海冰密集度产品并对产品精度进行了初步验证,验证结果表明:三个海冰类型已知区域的海冰密集度结果与理想值比较接近,多年冰密集度的反演精度需要进一步提高;本文结果与美国冰雪数据中心和德国不来梅大学提供的两种业务化海冰密集度产品一致。本研究为利用HY-2卫星监测极区海冰密集度变化,发布实时产品奠定了基础。 相似文献
107.
Since the 20th century, numerous Quaternary moraine dating methods have emerged, including lichenometric, moraine 14C, quartz sand thermoluminescence (TL), electron spin resonance (ESR), optically stimulated luminescence (OSL) and 10Be, 26A1, 36C1, 3H, 21Ne nuclide dating methods. These dating methods are widely applied to determine moraine ages and have provided a large dataset. Unfortunately each method has its defects. In this paper, we will review these various dating methods and provide some comments. 相似文献
108.
通过对南五凹钻井所揭示的阜宁组进行岩性、地球化学、古生物及地震相等综合分析证实,南五凹阜宁组发育中深湖相泥质烃源岩,且该套烃源岩形成于"广湖咸水"沉积环境。"广湖"即湖盆分布广泛,中深湖相泥质烃源岩在凹陷深洼处和缓坡带均有发育,平面上面积大,纵向上厚度大,具备生成油气的物质基础。"咸水"即烃源岩形成时期湖盆受到了海侵影响,致使水体性质偏咸。南五凹与中国东部古新世—始新世期间曾遭受海侵影响的其他湖盆类似,其形成的咸化烃源岩具有"排烃早"的特征。南五凹阜宁组湖相烃源岩"广湖咸水"沉积特征对于油气勘探具有重要意义。 相似文献
109.
讨论了网箱养殖、工厂化养殖和野生褐牙鲆的外观差异,对比分析了不同生长环境下褐牙鲆的肌肉营养成分和营养学价值。结果显示:网箱养殖的褐牙鲆体形、体色更接近野生褐牙鲆,即有眼侧呈深褐色,无眼侧呈白色;工厂化养殖褐牙鲆有眼侧体色较暗,无眼侧有黑斑。网箱养殖褐牙鲆脂肪含量(2.5%)远低于工厂化养殖的褐牙鲆(4.2%),而接近于野生的褐牙鲆(1.4%);网箱养殖褐牙鲆水分含量比工厂化养殖的高,也更接近野生的褐牙鲆。3种生长环境的褐牙鲆,氨基酸组成是一致的,而且各项比值也都符合FAO/WHO的标准。对比分析必需氨基酸指数(EAAI)和EPA+DPA、SFA、MUFA、PUFA等指标,网箱养殖褐牙鲆均要高于工厂化养殖褐牙鲆,接近而又优于野生的褐牙鲆。在矿物质含量方面,3种生长环境下的褐牙鲆差异不明显。综合各项指标分析,在褐牙鲆的3种生长环境中,网箱养殖的褐牙鲆要优于工厂化养殖的褐牙鲆,而更接近于野生的褐牙鲆。 相似文献
110.
<正>Erratum to:Chinese Journal of Oceanology and Limnology Vol.31 No.6,P.1190-1195,2013http://dx.doi.org/10.1007/s00343-013-3049-3The supporting grant information on the footnote of the original version of this article needs to be altered and updated.The new information is given below. 相似文献