青岛近海冬末春初海水碳酸盐体系的特征

通过在青岛近岸海域采集海水样品,测定了海水pH、总碱度(TA)、溶解无机碳(DIC)以及溶解钙离子,并根据这些参数计算了海水中的碳酸氢根、碳酸根等分量以及海水二氧化碳分压(pCO_2)、碳酸钙饱和度等参数。各站点海水pH范围为8.09~8.18,平均8.13;TA范围为2309~2345(mol/kg,平均2325(mol/kg;DIC范围为2158~2200(mol/kg,平均2180(mol/kg;海水中溶解钙离子的浓度为0.3700~0.3732g/kg,平均0.3716g/kg。求得海水pCO_2范围为371~476(atm,平均415(atm;方解石和文石的饱和度范围分别为2.31~2.84和1.45~1.78,平均值分别为2.57和1.61。通过与温度、盐度进行比较,发现冬末春初青岛近岸海域海水总碱度、溶解无机碳和溶解钙离子具有较为均匀的特征,是冬季混合导致的结果。海水pH有一定的变化性,与营养盐和叶绿素a的关系显示,观测区西部已开始增强的生物生产使海水pH升高,pH是该季节影响海水pCO_2、碳酸钙饱和度等参数的主要因素。该季节青岛近海总体上表现为大气CO_2的弱源,但西部海区是大气CO_2的弱汇。     

基于地面观测的遥感监测蒸散量验证方法研究

为了保证遥感监测蒸散量的准确性,需建立一套较完整的遥感监测蒸散量地面验证方法对其进行验证.通过由大孔径闪烁仪、涡动相关仪和自动气象站等组成的蒸散量观测系统可以获取不同卫星像元尺度蒸散量的地面观测值.自2002年以来,由海河流域的密云、馆陶、大兴及小汤山等站构建了一个不同卫星像元尺度蒸散量的观测站网,经过严格的观测数据处理与质量控制,获取了一大批卫星像元尺度蒸散量及其配套参数的地面观测值.同时,建立了一套基于地面观测的遥感监测蒸散量验证流程,重点对验证像元的选取以及评价指标的构建等进行探讨.依据上述验证流程,在海河流域的北京地区开展了遥感监测蒸散量的地面验证工作.利用2008年密云站和大兴站的大孔径闪烁仪观测数据,对基于MODIS数据估算的北京地区区域蒸散量进行验证.结果表明:这套基于大孔径闪烁仪观测数据的遥感监测蒸散量验证方法是合理、可行的.其中2008年北京地区遥感监测月、日蒸散量的均方差分别为13.75和0.91 mm,平均相对误差分别为22.79%、18.61%.     

Phylogenetic relationships within the genus Aspidisca (Protozoa, Ciliophora, Euplotida) revealed by ITS1-5.8S-ITS2 region sequences

The internal transcribed spacer regions (ITS1 and ITS2) and 5.8S rRNA genes were sequenced in six populations of four Aspidisca species, namely A. leptaspis, A. orthopogon, A. magna and A. aculeata. Phylogenetic trees were constructed by means of Bayesian inference (BI), Maximum Parsimony (MP), Neighbor-Joining (NJ), and Maximum Likelihood (ML) to assess the inter- and intra-species relationships within the genus Aspidisca. All trees show similar topologies with stable supports and indicate that: (1) four well known groups, i.e., Oligotrichia, Stichotrichia, Choreotrichia and Hypotrichia, are distinctly outlined within the class Spirotrichea, and all are monophyletic other than Hypotrichia; (2) members of Aspidisca can be distinguished well, based on the ITS1-5.8S-ITS2 region sequences, and A. leptaspis and A. magna shared a closer relationship than other species; (3) Aspidisca and Euplotes branch early in the subclass Hypotrichia. To compare the phylogenetic relationships based on different genes, SSU rRNA trees were also constructed with nearly the same species inclusion, which revealed different topologies of inter-species, inter-genera and inter-subclasses.     

The study on the effect of NO on the growth of Chaetoceros curvisetus

1 INTRODUCTION As a recently recognized information molecule in campaign of the “Molecule of the Year” by Sci- ence magazine, nitric oxide (NO) has attracted much attention from biologists and many other field scien- tists, for its very important physio…     

农民工住房存在的问题与解决对策——以郑州市为例

农民工是在我国城市化进程中产生的特殊群体,对城市经济的发展做出了巨大贡献。然而,诸多因素使得农民工依然处于社会底层,农民工的住房问题是各界人士关注的重点问题之一。以郑州市为例,在问卷调查、实地访谈、统计分析的基础上,根据农民工住房存在的问题,借鉴国内外的成功经验,提出了解决农民工住房问题的对策。主要对策有改革二元户籍制度,拓宽廉租房供给渠道,制定农民工租房补贴政策,遏制房地产市场投机等。     

日照海洋保护区现状及发展对策研究

人类对海洋的青睐和倚重日益凸显为实现海洋未来可持续发展建立海洋保护区是一种有效的预防性海洋综合管理方式。文章根据日照海洋保护区当前发展状况,分析保护区发展中存在的问题,并相应的提出相关建议及对策。希望这些对策能够进一步提高保护区的保护价值。     

Heavy Oil and Oil Sands:Global Distribution and Resource Assessment

Global recoverable resources of heavy oil and oil sands have been assessed by CNPC using a geology-based assessment method combined with the traditional volumetric method, spatial interpolation method, parametric-probability method etc. The most favourable areas for exploration have been selected in accordance with a comprehensive scoring system. The results show:(1) For geological resources, CNPC estimate 991.18 billion tonnes of heavy oil and 501.26 billion tonnes of oil sands globally, of which technically recoverable resources of heavy oil and oil sands comprise 126.74 billion tonnes and 64.13 billion tonnes respectively. More than 80% of the resources occur within Tertiary and Cretaceous reservoirs distributed across 69 heavy oil basins and 32 oil sands basins. 99% of recoverable resources of heavy oil and oil sands occur within foreland basins, passive continental-margin basins and cratonic basins.(2) Since residual hydrocarbon resources remain following large-scale hydrocarbon migration and destruction, heavy oil and oil sands are characterized most commonly by late hydrocarbon accumulation, the same basin types and source-reservoir conditions as for conventional hydrocarbon resources, shallow burial depth and stratabound reservoirs.(3) Three accumulation models are recognised, depending on basin type: degradation along slope; destruction by uplift; and migration along faults.(4) In addition to mature exploration regions such as Canada and Venezuela, the Volga-Ural Basin and the Pre-Caspian Basin are less well-explored and have good potential for oil-sand discoveries, and it is predicted that the Middle East will be an important region for heavy oil development.     

遗传神经网络在烈度评估中的研究与应用

准确判定极震区烈度是震后应急工作高效开展的重要基础。收集1966—2017年发生在中国大陆地区M_S 5.0以上有详细烈度记录的地震事件322例，选取与极震区烈度有关的7个因子进行主成分分析，将提取的主成分确定为BP神经网络的输入，极震区烈度为输出，在遗传算法优化的基础上，构建用于极震区烈度预测的BP神经网络模型。结果显示，与传统模型相比，神经网络模型在预测误差分布、精度和预测结果正确率等方面都具有明显的优越性。     

基于北斗数据的非差相对定位理论与方法研究

简要介绍了北斗导航定位系统,论述了非差相对定位的基本概念、原理及建立非差相对定位模型的基本原则,介绍了建立单历元非差相对定位模型的函数模型和随机模型的详细过程,利用LAMBDA方法实现基线单历元模糊度的固定。对单历元非差相对定位的基线解算精度进行了重点分析。