空化水射流技术在海洋污损生物清除领域的应用研究

文章从海洋污损生物的危害分析入手,首先概述海洋污损生物的清除方法,并结合空化水射流技术的原理与优势开展实例应用研究,指出空化射流清洗技术是一种切实可行的新型清洗技术,可以在不破坏设施表面完整防腐层的基础上,高效、安全地清洗水下设施表面附着的海洋生物污垢层;最后对空化水射流技术进行展望,指出其关键技术在于空化射流喷嘴的设计和ROV自动控制系统的研制。     

Nonparametric Estimation of Undrained Shear Strength for Normally Consolidated Clays

For decades, various well-known empirical correlations have been established and commonly used to estimate the undrained shear strength of normally consolidated clays in geotechnical practice. However, there are still many contradictory cases regarding the validity of these correlations, so their applicability and reliability are questionable. In this study, an extensive geotechnical database for normally consolidated clays has been compiled. Next, a Bayesian nonparametric method is exploited to identify the most critical soil index properties in inferring the undrained shear strength and a new predictive model is proposed. Finally, the performance of the proposed predictive model is assessed and compared with two well-known correlations using an independent testing database. It confirms that the proposed model not only possesses high predictability, but also provides superior performance over other existing empirical correlations.     

深海鲣鱼(Katsuwonus pelamis)眼窝油中DHA和EPA的提取及其抗抑郁活性研究

为了探索鲣鱼(Katsuwonus pelamis)鱼头眼窝肉中的DHA(C22:6n3)和EPA(C20:5n3)的抗抑郁活性效果,采用现代食品分离技术分离提取鲣鱼眼窝肉中的DHA和EPA,并对其抗抑郁活性效果进行研究。研究结果发现,当DHA和EPA剂量分别为50,100和300mg/kg时,能够对强迫游泳实验和悬尾实验的小鼠产生抗抑郁作用,其中低剂量(50mg/kg)表现为最活跃。DHA和EPA还能够对引起头抽动综合征的5-羟色胺小鼠产生轻微的增强作用。通过高效液相色谱-电化学法同时测定小鼠大脑区域内主要的单胺类神经递质及其代谢产物。本实验发现,与用压力媒介物处理的小鼠相比,DHA和EPA能够显著增加主要神经递质5-羟色胺和去肾上腺素在小鼠海马体、下丘脑及皮质层中的浓度,并减少5-羟色胺的代谢。DHA和EPA能够在预测抗抑郁特性的动物模型中(强迫游泳实验,悬尾实验)明确其具有抗抑郁活性效果,具有潜在的生物医学应用前景和环保效应。     

Prokaryotic community composition revealed by denaturing gradient gel electrophoresis in the East Sea

To understand the temporal and spatial variation of the prokaryotic community in the East Sea, their composition was determined by polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE)-sequencing techniques. The investigations were conducted twice annually in 2007 and 2009 in coastal and offshore stations. Prokaryotic abundance (PA), leucine incorporation rate, and other environmental parameters were also measured. By using the DGGE approach, we obtained 283 bacterial sequences and 160 archaeal sequences. The most frequently detected bacterial phylotypes during the investigations belonged to Alphaproteobacteria, Gammaproteobacteria, and Bacteroidetes. However, their relative compositions differed in time and space. Although Alphaproteobacteria and Bacteroidetes were the dominant groups in the surface water in May 2007 and in May and October 2007, Gammaproteobacteria was dominant in mesopelagic samples. However, Gammaproteobacteria was overwhelmingly dominant in most samples in August 2009. Although Deltaproteobacteria was rarely found as a dominant bacterial group, it occupied the highest fraction in a mesopelagic sample in October 2007. Epsilonproteobacteria also showed a similar trend, although its maximal dominance was found in a mesopelagic sample in August 2009. The archaeal community was dominated overwhelmingly by members of the Euryarchaeota in most of the investigations. However, Nitrosopumilales was dominant in aphotic samples in August 2009. Further, their spatiotemporal composition at the family level changed more dynamically in the East Sea. These temporal and spatial distributions of the prokaryotic community were influenced mainly by seawater temperature and depth in the East Sea.     

Comparative assessment of semantic-sensitive satellite image retrieval: simple and context-sensitive Bayesian networks

In recent years, Bayesian networks using unsupervised extracted image features have been applied in many remote sensing information mining systems to enable semantic-sensitive image retrieval. However, a simple Bayesian network insufficiently accounts for the spatial information, that is, the relations among image regions, for the semantic inference process. This drawback significantly impacts the retrieval performance, especially if the utilised features contain no or little spatial information. Therefore, this article proposes a context-sensitive Bayesian network, which infers semantic concepts of image regions based on the spectral and textural characteristics of the regions themselves as well as their contexts, that is, the adjacent regions. In order to compare the context-sensitive Bayesian network with the simple Bayesian network, comprehensive experiments were conducted based on high-resolution multispectral IKONOS imagery. The results show that the incorporation of the image regions' spatial relations not only significantly improves the accuracy of the semantic concepts inference, but also allows more flexibility in choosing the type of low-level features.     

区域地震信息网站简易备份策略和实现

本文在综合分析地震行业区域中心门户网站基础架构的基础上,根据地震信息发布的安全需求,对网站数据备份与恢复的技术和策略进行了分忻,提出了一种简单易行的网站数据备份与恢复的流程和机制,并在实际应用中得到运用。该方法简单实用和易行,为网站技术系统的运行维护提供了一种借鉴模式。     

基于GIS与ANN耦合技术的地裂缝灾情非线性模拟预测系统——以山西榆次地裂缝灾害为例

现代地裂缝在世界许多国家普遍存在 ,已成为当今世界范围内的主要地质灾害之一。本文在详尽分析了山西榆次地裂缝的各个致灾因子的基础上 ,利用GIS技术建立了地质学意义上的专题层 ;然后采用人工神经网络技术构建出了地裂缝灾害活动性的评价模型 ,并建立了地裂缝活动性的评价系统 ,对榆次地裂缝进行了灾害活动性评价 ,为榆次市城建和国土规划等部门的正确决策提供了重要的科学依据     

东营凹陷沙四段碳酸盐岩稀土元素地球化学特征

东营凹陷古近系沙河街组碳酸盐岩的成因一直存在湖相与海相之争。沙四段碳酸盐岩呈厚薄不等的夹层赋于陆相碎屑岩中。本文对研究区代表性碳酸盐岩样品稀土元素地球化学特征的分析表明:东营凹陷古近系沙四段碳酸盐岩的∑LREE > ∑MREE > ∑HREE,MREE相对于HREE富集;不具备Ce/Ce^*负异常特征;Y/Ho值为25.5~34.1,La/La^*值为0.99~1.21;Y/Ho-La/La^*呈负相关关系。所有这些特征均与湖相成因碳酸盐岩一致,沙四段碳酸盐岩的形成应为湖相成因。     

Formation of chlorite rims and the impact of pore-lining chlorite on reservoir quality: a case study from Shiqianfeng sandstones in upper Permian of Dongpu Depression,Bohai Bay Basin,eastern China

The source material, precursor and formation processes of chlorite rims, and impact of pore-lining chlorite on reservoir quality of the Shiqianfeng sandstones, Dongpu Depression, Bohai Bay Basin, China, are studied using an integrated approach, including core observation, point-count analysis of thin-sections, scanning electron microscopy, electron microprobe analysis and cathode luminescence. The petrographic analysis shows that chlorite rims consist of grain-coating chlorite, poorly crystalline pore-lining chlorite and euhedral-crystallised pore-lining chlorite. The chemical composition shows that pore-lining chlorite is mainly Fe-rich with an average of 0.785 for Fe/(Fe+Mg) ratio. Petrographic analysis shows a large amount of volcanic dust (3.0～16.0 vol%, average of 7.93 vol%) in Shiqianfeng sandstones, which determines the formation of poorly crystalline pore-lining chlorite. Transformation of volcanic dust to smectite rims started with shallow burial depth at an early diagenetic stage, followed by in situ alteration of the smectite rims to poorly crystalline chlorite rims. Euhedral-crystallised chlorite mainly develops in sandstones with high porosity, high permeability and open flow systems. Pore-lining chlorite can inhibit quartz overgrowth but cannot effectively prevent pore-filling of authigenic quartz, carbonate and kaolinite cements, and therefore cannot prevent porosity destruction. However, the occurrence of pore-lining chlorite is a barometer of good reservoir quality and intense hydrodynamic conditions.     

输入界面对场地地表地震动参数的影响

本文以江淮地区典型场地资料为原型,选取不同深度的岩层位置作为地震动输入界面,构造多种场地土层模型,选择Taft、Kobe和E1centro 3条强震记录作为地震输入,采用一维频域等效线性化波动方法重点分析了地震动输入界面对场地地表地震动参数的影响。研究结果表明,随着输入界面深度的增加,场地地表的峰值加速度逐渐增加,且增加的幅度呈逐渐减小的趋势,但输入界面深度对地表加速度反应谱特征周期的影响较小;输入界面剪切波速值对反应谱特征周期影响有限,但对地表峰值加速度影响较为显著,地表峰值加速度随着输入界面剪切波速的增大而增大,且两者的增幅呈现近似的线性关系。