A New Basal Titanosaur (Dinosauria: Sauropoda) from the Early Cretaceous of China

A new dinosaur of Early Cretaceous age was recently discovered from the Mazongshan area of northwestern Gansu Province, China. The new dinosaur represents a new genus and species of Sauropoda, and is among the most basal members of Titanosauria. Its finding also suggests that titanosaurs might have originated in Asia no later than the Early Cretaceous.     

Determining anisotropic transmissivity using a simplified Papadopulos method

The straight-line method presented by Papadopulos requires a minimum of three observation wells for determining the transmissivity tensor of a homogeneous and anisotropic aquifer. A simplification of this method was developed for fractured aquifers where the principal directions of the transmissivity tensor are known prior to implementation, such as when fracture patterns on outcropping portions of the aquifer may be used to infer the principal directions. This new method assumes that observation wells are drilled along the two principal directions from the pumped well, thus reducing the required number of observation wells to two. This method was applied for an aquifer test in the fractured Navajo Sandstone of southwestern Utah and yielded minimum and maximum principal transmissivity values of 70 and 1800 m(2)/d, respectively, indicating an anisotropy ratio of approximately 24 to 1.     

Can industrial pollution cause intersexuality in the amphipod, Echinogammarus marinus?

Following recent studies, in which intersex and/or reproductive abnormalities have been observed in a number of crustaceans in association with pollution, the prevalence of intersexuality in the amphipod, Echinogammarus marinus was monitored at sites receiving industrial discharges for one year in 2002/2003. Based upon reports of intersexuality occurring in amphipods due to feminising microsporidian parasites, the occurrence, and role of microsporidian parasites in causing intersex was investigated through histological examination. Results demonstrate a significantly higher prevalence of intersex organisms was found at sites receiving industrial discharges throughout the year when compared to a reference site, with the phenotype of intersex (intersex male and intersex female) varying in its dominance between impacted sites. Intersex specimens were significantly more likely to be infected with microsporidian parasites at sites receiving discharges than reference sites, however relatively few specimens (normal or intersex) were infected at reference sites suggesting parasitism is not the only cause of intersex. The direct/indirect role of pollution in the observed intersexuality is discussed.     

水产饲料中三聚氰胺检测方法的优化

通过对高效液相色谱法(HPLC)测定水产饲料中三聚氰胺含量的方法进行优化,得到最佳色谱条件和前处理方法,建立了水产饲料中三聚氰胺的检测方法。结果表明:以体积比8∶92的乙腈、庚烷磺酸钠离子对试剂为流动相,柱温40℃,流速1.2 mL/min,以波长236 nm检测;以提取液为18 mL50%(φ)乙腈水+1 mL乙酸锌+1 mL1mol/L盐酸,淋洗液3 mL水和3 mL甲醇,洗脱体积6 mL作样品前处理。三聚氰胺加标回收率为85%～100%,相对标准偏差(RSD)小于5%,线性范围为0.2 mg/L～5.0mg/L,相关系数0.999 8,方法检出限为0.2 mg/kg。     

Reflectance spectroscopy and geochemical analyses of Lake Hoare sediments, Antarctica: implications for remote sensing of the Earth and Mars

Visible to infrared reflectance spectroscopic analyses (0.3-25 micromoles) have been performed on sediments from the Dry Valleys region of Antarctica. Sample characterization for these sediments includes extensive geochemical analyses and X-ray diffraction (XRD). The reflectance spectra and XRD indicate major amounts of quartz, feldspar, and pyroxene in these samples and lesser amounts of carbonate, mica, chlorite, amphibole, illite, smectite, and organic matter. Calcite is the primary form of carbonate present in these Lake Hoare sediments based on the elemental abundances and spectroscopic features. The particle size distribution of the major and secondary components influences their detection in mixtures and this sensitivity to particle size is manifested differently in the "volume scattering" and "surface scattering" infrared regions. The Christiansen feature lies between these two spectral regimes and is influenced by the spectral properties of both regions. For these mixtures the Christiansen feature was found to be dependent on physical parameters, such as particle size and sample texture, as well as the mineralogy. Semiquantitative spectroscopic detection of calcite and organic material has been tested in these quartz- and feldspar-rich sediments. The relative spectral band depths due to organics and calcite correlate in general with the wt% C from organic matter and carbonate. The amounts of organic matter and carbonate present correlate with high Br and U abundances and high Ca and Sr abundances, respectively. Variation in the elemental abundances was overall minimal, which is consistent with a common sedimentary origin for the forty-two samples studied here from Lake Hoare.     

板块构造,板块运移机制及裂谷作用

一系列西半球大陆分布的古地理分析认为，通过缓慢对流的下层岩石圈的上地幔施加到岩石圈底部的磨擦力在驱驶板块运动机制上可起到重要作用。通过这样的简化，与软流圈上涌以及与在造山带处岩石圈过厚有关的岩片抽拉和岩层波状起伏，洋脊推动和张应力偏量可以被认为是次要的板块运移力。全球的现在应力状态以及整个地质证据说明了主压应力可以通过大陆和海洋岩石圈远距离传送。主要大陆块体的组合（象ｐａｎｇｅａ联合古陆）可能具有单一施加在上地幔对流系统的效应。上地慢对流系统导致了大陆块体的衰亡和重组，由岩石圈中偏张应力的发育以及由施加在巨大大陆底部之上拖曳力引起大陆分裂，形成新的软流圈上涌体系。岩石圈扩张在断裂处形成高峰，接着软流圈物质主动平流进入到两个分散板块之间，作为洋壳加积。与此同时，洋隆对板块分散起着推动力的作用。如果远区域挤压应力阻止了不同板块进一步离散的话，沿着洋底的扩张轴的活动性可能突然终止。这可以解释在板块边界重组期间通常在远距离区域海底扩张轴的几乎同时消亡特征。假设一个有限的球体，在海底扩张轴处新的洋壳岩石圈的产生一定与由洋壳岩石圈消减数量和／或大陆地壳和下部地壳物质消减以及亚地壳消减地方的数量相匹配。由地慢对流系统以及     

导航电子地图信息更新采集方法研究

对导航电子地图信息更新采集的常规方法作了介绍及分析,提出了一套行之有效的综合利用多信息源收集导航电子地图数据更新信息的方法,使之能有效指导外业数据采集、加快导航电子地图的更新周期、提高用户满意度,同时提出了今后更新信息收集的发展方向和建议。     

新型的自动标定器

介绍了一种新型的自动标定装置 ,阐述了簧板标定器的基本工作原理及其自动控制系统。该装置结构简单 ,可方便地组合成人工和自动标定器。给出了簧板标定器的初步测试结果 ,表明簧板标定器完全满足形变仪器的要求。