利用SPOT 5参数进行严密物理模型法纠正方法研究

通常SPOT 5影像的纠正基本上利用共线方程法、有理函数计算法与多项式计算法进行,这些方法对于平坦和丘陵地区比较有效,但对于山区就难以达到理想精度。介绍了一种利用SPOT 5提供参数,按照严密物理模型进行纠正的方法,这种方法对于起伏较大的山区比较有效。试验表明,利用严密物理模型纠正的影像平均精度优于15 m,达到1∶10 000制图需要,从而可以利用1∶10 000图件更新土地利用现状图和土地利用数据库,以及进行土地变更调查。     

SMA-橡胶支座的力学性能试验研究

SMA-橡胶支座是一种由叠层橡胶垫和形状记忆合金（SMA）复合而成的新型隔震支座。阐明了SMA-橡胶支座的设计思路和工作机理,通过SMA-橡胶支座实物模型的伪动力试验,考察了支座的水平和竖向刚度、耗能能力和等效阻尼比,研究了位移幅值、加载频率、竖向荷载等参数对支座力学性能的影响。研究结果表明,SMA-橡胶支座工作性能稳定,耗能能力较强,是一种性能优良的新型隔震装置。     

南水北调西线工程深埋隧道地质超前预报系统研究的思考

深埋长隧道是南水北调西线工程施工中的难点,隧道地质超前地质预报可分为施工前地质预报和施工阶段地质预报,目前施工前地质预报应用的可控源音频大地电磁法及施工阶段应用的地质雷达、TSP、红外辐射测温技术有一定的效果,但是针对南水北调西线工程这样复杂的岩层,必须对现有的预报方法进行改进.     

乌梁素海氮污染及其空间分布格局

针对草型富营养化湖泊乌梁素海富营养化日趋严重和湿地面积逐渐萎缩的现实,本文系统地研究了TN、NH4+-N、NO3--N和Org-N在上覆水与沉积物中的分布规律。结果表明,上覆水中TN含量平均为1.78mg/L,且无机氮污染以NH4+-N为主,占无机氮总量的69%以上;表层沉积物中氮素的水平分布格局均体现出西高东低的经向分异特征并主要以Org-N的形式存在;表层沉积物中TN对底栖生物已经具有一定的生态毒性效应并正由最低级向严重级过渡;氮素在乌梁素海沉积剖面上均表现出随深度增加而含量递减的规律,表层0¹0cm的TN平均含量达到1.28g/kg,分别为10²2cm和22⁴0cm的1.6和1.9倍,揭示了乌梁素海富营养化进程加速始于20世纪90年代。     

北苏鲁超高压变质岩锆石中的矿物包体

北苏鲁莒南—岚山头—日照—桃行—仰口—荣成—威海一带榴辉岩的围岩经历了强烈角闪岩相退变质作用的改造,峰期超高压矿物组合已完全被后期退变矿物组合所取代。锆石微区阴极发光图像和矿物包体激光拉曼测试研究结果表明,132件不同类型岩石(包括榴辉岩、斜长角闪岩、正片麻岩、副片麻岩、大理岩、蓝晶石英岩、云母片岩和钙镁硅酸盐类变质岩等)锆石中,普遍隐藏以柯石英为代表的超高压矿物包体。此外,在南苏鲁东海及其邻区的地表露头和一系列钻孔岩心的锆石中,也普遍发现以柯石英为代表的超高压矿物包体。该项研究成果表明,在苏鲁地体由榴辉岩及其围岩的原岩所组成的陆壳岩石(约320km×20km×5km)曾发生过巨量物质深俯冲—超高压变质的壮观地质事件。     

基于加权水平精度因子的伪卫星基站选择方法

提出一种以加权水平精度因子为依据的基站选择方法,该方法根据基站和用户的相对位置给予每个基站不同的权值,降低测量误差较大的基站被选中参与定位的可能性。通过对伪距测量误差数学模型的分析,推导伪卫星定位系统加权矩阵,并设计了基于基站对WHDOP贡献的基站选择方法。仿真结果表明,该方法能更加高效、准确地实现伪卫星基站的选择,降低接收机的计算量,提高系统的定位精度。     

Distribution Patterns of Major and Trace Elements and Provenance of Surface Sediments on the Continental Shelf off Western Guangdong Province and Northeastern Hainan Island

A coupled approach based on grain size and geochemical elements is used to trace the provenance of surface sediments and to confirm the distribution patterns of grain size and elements on the continental shelf off western Guangdong Province and northeastern Hainan Island. The mean grain size ranges from 0.05 φ to 7.28 φ with a mean value of 5.60 φ. The average concentrations of major elements descend in the order of SiO_2Al_2O_3CaOFe_2O_3K_2OMgONa_2OTiO_2 P_2O_5 MnO, while those of trace elements exhibit a descending order of Sr Rb Zn V Cr Pb Ni Cu As Cd. On the basis of the distribution patterns of elements and results of statistical analysis, the study area is classified into three zones. Zone I locates on the continental shelf off western Guangdong Province, and the sediments are mainly from Pearl River, Taiwanese rivers, and small rivers nearby. Zone II locates in the eastern exit of Qiongzhou Strait and the coastal area off Leizhou Peninsula, and the sediments are mainly from the erosion products of Qiongzhou Strait and Hainan Island. Zone III locates off the eastern Hainan Island and the continental shelf deeper than-50 m isobaths, and the sediments are mainly from Hainan Island and coral reef. The influence from open water should also be considered. Results indicate that the grain size is the main controlling factor for major and trace element contents and that anthropogenic impact and biological activity also play an important role in the distribution of these elements.     

Formation of an anticyclonic eddy and the mechanism involved: a case study using cruise data from the northern South China Sea

Data from satellite altimetry and in situ observations together with the Hybrid Coordinate Ocean Model(HYCOM)reanalysis data were used to investigate the mechanism and formation of an anticyclonic eddy in the northeastern South China Sea(SCS).Analysis of water mass using cruise data indicated that the water captured in the eddy differs from those in the SCS,the Kuroshio intrusion,and the eddy-forming region.Data from sea surface height(SSH)and sea level anomaly(SLA)indicate that the eddy formed due both to the Kuroshio intrusion and the local circulation in the SCS.The Kuroshio intrusion is present at the start of the eddy growth(March 5-9)before Kuroshio leaps the Luzon Strait.The eddy then becomes larger and stronger in the absence of the Kuroshio intrusion.From the eddy budget of the HYCOM reanalysis data,the formation of the eddy goes in three steps.By the third step,the eddy had become affected by variations of local SCS circulation,which is more strongly than in the first step in which it is affected more by the Kuroshio intrusion.The variability of the temperature and salinity inside the eddy provide a support to this conclusion.The water in the SCS intruded into the eddy from the southeast,which decrease the salinity gradually in the southern part of the eddy during the growth period.     

The Light Regime Effect on Triacylglycerol Accumulation of Isochrysis zhangjiangensis

Stress state of microalgal cells is caused under unfavorable conditions such as disordered light regime and depleted nitrogen. The stress state can impair photosynthetic efficiency, inhibit cell growth and result in the accumulation of triacylglycerol(TAG) from protective mechanisms. Continuous light or nitrogen starvation was applied on microalgae and performed effectively on inducing TAG production. To evaluate the light regime effect on inducing TAG production, the effect of different light regimes on nitrogen-starved Isochrysis zhangjiangensis was investigated in this work. The continuous light and nitrogen starvation elevated TAG content of biomass by 73% and 193%, respectively. Furthermore, the TAG accumulation of I. zhangjiangensis cell under nitrogen starvation decreased under aggravated stress from continuous illumination. Our results demonstrated that culturing the cells with 14 L: 10 D light regime under nitrogen starvation is the optimal mode to achieve maximal accumulation of TAG. A recovery in light regime was necessary for I. zhangjiangensis cultivation.