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Nutrient compositions of cultured Thalassiosira rotula and Skeletonema costatum from the Jiaozhou Bay in China

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Acta Oceanologica Sinica 2008年第4期27卷 147-155页

作者： shen zhiliang WU Yulin LIU Qun YAO Yun Key Laboratory of Marine Ecology and Environmental Sciences Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China

Carbon, nitrogen, phosphorus, silicon composition of cultured two different sized phytoplankton common species of Thalazsiosira rotula and Skeletonema costatum from the Jiaozhou Bay were measured. Carbon, nitrogen, phosphorus, silicon contents in cell were obvious higher in T. rotula than in S. costatum, but the percents of nitrogen, phosphorus, sihcon contents in cell dry mass in T. rotula were lower than those in S. costatum. The dry mass concentrations of nitrogen,phosphorus, silicon in S. costatum were much higher than those in T. rotula, particularly silicon, the former was 6. 4 times of the latter, showing that S. costatum could more assimilate these elements. Especially, S. costatum had competitive dominance for assimilating silicon, which is beneficial to its becoming a major dominant species in relative short silicon of the Jiaozhou Bay. There were some differences in numerical value of nutrient ratios both laboratory-cultured phytoplankton and different sized suspended particulates （ mainly phytoplankton） in the Jiaozhou Bay, which was caused by the changes of environment. High contents of carbon, nitrogon and relative low phosporus, sil- icon, high molar ratio of nitrogen to phosphorus （far higher than Redfield value） and low ratio of silicon to phosphorus and silicon to nitrogen （far lower than Redfield values） in the two diatoms and different sized suspended particulates were consistent with those in the seawater. Relative short silicon in the seawater and phytoplankton showed that silicon was possibly affectting phytoplankton growth in the Jiaozhou Bay.

关键词： carbon nitrogen phosphorus,silicon composition Skeletonema costatum Thalazsiosira rotula Jiaozhou Bay

Acoustic emission characteristics and stress release rate of coal samples in different dynamic destruction time

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International Journal of Mining Science and Technology 2016年第6期26卷 981-988页

作者： Xiao Fukun Liu Gang Zhang Ze shen zhiliang Zhang Fengrui Wang Yifei Key Laboratory for Ground Pressure and Gas Control in Deep Mining of Heilongjiang Province Heilongjiang University of Science and Technology

Considering the importance of the prediction of rock burst disasters, and in order to grasp the law of acoustic emission(AE) of coal samples in different dynamic destruction time, the SH-II AE monitoring system was adopted to monitor the failure process of coal samples. The study of the change rule of the AE numbers, energy, ‘b' value and spectrum in the micro crack propagation process of the coal samples shows that as dynamic damage time went by, AE presented high-energy counts and the accumulated counts increased during the compression phase. The AE energy and cumulative counts increased during the elastic stage. The AE blank area increased gradually and the blank lines were more and more obvious in the molding stage. The AE counts and energy showed a trend of decrease in the residual damage *** ‘b' values gradually became sparse, and the large scale cracks percentage compared with micro cracks decreased and the degree of damage decreased. The AE frequency spectrum peak went from the residual damage phase to the molding phase, and finally it was nearly stable, besides the bandwidth of the main frequency is gradually narrowed. Also, the frequency peak changed from single peak frequency to bi-peak frequency and to the single peak frequency. Uniaxial compressive strength is more sensitive than the elastic modulus to dynamic damage time.

关键词： Dynamic destruction time Acoustic emission Outburst-proneness Stress release rate

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长江磷和硅的输送通量

地理学报 2006年第7期61卷 741-751页

作者：沈志良中国科学院海洋研究所生态与环境科学重点实验室青岛266071

于1997年枯水期(11月～12月)和1998年丰水期(8月和10月),对长江流域从金沙江至河口干流和主要支流、湖泊各种形式的磷和硅酸盐进行了调查。长江干流枯、丰期颗粒磷和总磷浓度变化几乎是同步的,上游快速增加,中、下游下降且变化不大;溶... 详细信息

于1997年枯水期(11月～12月)和1998年丰水期(8月和10月),对长江流域从金沙江至河口干流和主要支流、湖泊各种形式的磷和硅酸盐进行了调查。长江干流枯、丰期颗粒磷和总磷浓度变化几乎是同步的,上游快速增加,中、下游下降且变化不大;溶解态磷和硅酸盐浓度变化较小。枯、丰期各种形式磷和硅酸盐通量从上游至中、下游呈增加趋势。枯水期长江各种形式磷和硅酸盐通量,大部分是由中、下游贡献的,其中一半以上来自于支流和湖泊。丰水期各种形式磷和硅酸盐的输送,仅上游支流贡献了一半以上的颗粒磷,其余大部分是由干流贡献的。颗粒磷所占的比例,上游高于中、下游,丰水期高于枯水期,干流高于支流,主要与悬浮泥沙含量有关,颗粒态磷是长江磷的主要贡献者。溶解态磷的输送通量,枯水期干流中有机磷略占优势,支流中有机和无机磷各占一半;丰水期均是无机磷占优势。长江水中各种形式磷和硅酸盐的输送通量和总磷、磷酸盐的输出通量主要受径流量所控制,特别是硅酸盐通量具有比磷更加明显的随径流而增加的特征。本文提出了长江各种形式磷和硅酸盐的输送通量方程式及总磷、磷酸盐的输出通量方程式。

关键词：磷硅酸盐径流量输送通量长江

NUTRIENTS IN SEAWATER AND INTERSTITIAL WATER OF THE SEDIMENTS IN THE HUANGHE RIVER ESTUARINE AREA (NOVEMBER)

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Chinese Journal of Oceanology and Limnology 1988年第2期6卷 104-114页

作者：沈志良刘兴俊陆家平 Institute of Oceanology Academia Sinica Qingdao

The investigation shows that the concentrations of nutrients are high in estuarine and coastal waters and low in offshore waters. The concentration of nitrate in estuaries is controlled through a physical mixing process and is also affected by hiotic activity. The annual transport of total inorganic nitrogen and dissolved phosphate-phosphorus from the Huanghe River water to the sea is about 8.45×104 and 1.45×103 tons respectively. The distributions of inorganic nitrogen and silicate in interstitial water of surface sediments are similar to those in surface and bottom sea water. Their contents in interstitial water are227 552μmol/l （average 375） for ammonia, 0.31 -9.0μmol/l （average 1.6） for nitrite, 0 41μmol/1 （average 6.0） for nitrate, and 41 139μmol/l （average 77） for silicate. The average concentrations of phosphate in the surveyed area are 0.64μmol/l for seawater and 1.2μmol/l for interstitial water. A cycle of phosphate in the estuary is also suggested in this paper.

关键词： NOVEMBER NUTRIENTS IN SEAWATER AND INTERSTITIAL WATER OF THE SEDIMENTS IN THE HUANGHE RIVER ESTUARINE AREA than

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循环加卸载中滞回环与弹塑性应变能关系研究

岩石力学与工程学报 2014年第9期33卷 1791-1797页

作者：肖福坤申志亮刘刚张泽张峰瑞黑龙江科技大学黑龙江省煤矿深部开采地压控制与瓦斯治理重点实验室黑龙江哈尔滨150022

为了探求煤层冲击倾向性鉴定时循环加卸载中滞回环与弹塑性应变能的关系,利用电液伺服试验机对煤样进行单轴循环加卸载试验。对试验所得循环加卸载应力–应变曲线、循环次数与滞回环面积曲线、弹性应变能与滞回环面积关系等进行分析。... 详细信息

为了探求煤层冲击倾向性鉴定时循环加卸载中滞回环与弹塑性应变能的关系,利用电液伺服试验机对煤样进行单轴循环加卸载试验。对试验所得循环加卸载应力–应变曲线、循环次数与滞回环面积曲线、弹性应变能与滞回环面积关系等进行分析。得出结论如下:(1)随着循环次数的增加,循环次数和弹性应变能与滞回环面积呈正相关。(2)滞回环产生于循环加卸载过程的压密阶段。当煤样接近破坏时,压密阶段的不可逆塑性形变达到最大。(3)每一次循环的塑性能是新生成裂纹的耗散能,以往的弹性能量指数计算中未将压密裂纹形成的耗散能(滞回环面积)去掉,导致指数计算结果偏小,因此提出弹性能量指数修正计算公式。提出的修正公式可使煤层冲击倾向性鉴定时的弹性能量指数计算更精确。

关键词：岩石力学弹性应变能滞回环循环次数滞回环面积

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胶州湾营养盐及富营养化特征

海洋通报 2007年第4期26卷 91-98页

作者：姚云郑世清沈志良青岛科技大学计算机与化工研究所山东青岛266042 中国科学院海洋研究所海洋生态与环境科学重点实验室山东青岛266071

根据2003—2004年在胶州湾的调查资料,探讨了该湾营养盐及其富营养化状态。通过spss12.0统计分析营养盐和各理化因子之间的两两相关性,认为溶解无机氮、活性磷酸盐和活性硅酸盐之间有一定程度相似的生物地球化学过程,且外源性营养盐是... 详细信息

根据2003—2004年在胶州湾的调查资料,探讨了该湾营养盐及其富营养化状态。通过spss12.0统计分析营养盐和各理化因子之间的两两相关性,认为溶解无机氮、活性磷酸盐和活性硅酸盐之间有一定程度相似的生物地球化学过程,且外源性营养盐是其主要的来源。频数分析显示,胶州湾硅酸盐浓度控制了SiO3-Si/PO4-P和SiO3-Si/DIN的比例,此二者多数情况下小于其各自的化学计量平衡。冬季营养盐和叶绿素a的消长关系及浮游植物赤潮优势种数量变化分析说明,硅酸盐的含量对调查海域赤潮的发生发展和消退起着重要的控制作用。这些表明,SiO3-Si是胶州湾浮游植物生长的潜在限制因子,特别是冬季。利用Matlab建立了人工神经网络富营养化评价模型,结果认为带有SiO3-Si因子的评价结果更好地反映了胶州湾的富营养化状况。

关键词：胶州湾营养盐富营养化