不同海域沉积物对尿素吸附的实验模拟研究     

薛峤娜  胡博  谭丽菊  王江涛 《海洋学报》2018,40(10):190-199

本文对采自渤海、黄海和东海3个典型海域的沉积物进行了尿素吸附/解吸的实验室模拟研究，用Freundlich吸附模型和Henry吸附模型分析了不同沉积物对尿素吸附的热力学特性，并研究了温度、沉积物粒径、有机质含量等因素对尿素在沉积物表面吸附的影响。结果表明，沉积物对尿素的吸附/解吸过程总体呈现3个阶段:快速吸附阶段（0~5 h）—慢速吸附阶段（5~12 h）—平衡阶段（12 h之后）。当水体中的尿素浓度较低时，沉积物解吸释放尿素，随着上覆水中尿素浓度逐渐增加，沉积物对上覆水中的尿素产生吸附行为，各海区沉积物对尿素的吸附能力由强至弱依次为渤海、东海、黄海，这可能与沉积物的类型有关。Freundlich方程和Henry方程均可模拟沉积物对尿素的吸附，温度、粒径以及沉积物中有机质含量等因素均对尿素在沉积物上的吸附产生影响，随着温度升高，尿素在沉积物上的吸附量变小，沉积物粒径越小，有机质含量越高，吸附尿素的能力越强，因此，揭示尿素在沉积物表面的环境行为时，必须考虑以上因素的影响。  相似文献   

基于碳、氮稳定同位素的雅浦海沟底栖生物食物来源和营养级初探     

郭承秧  杨志  陈建芳  郑豪  张东声  冉莉华  王春生  鹿博  陈倩娜 《海洋学报》2018,40(10):51-60

为了分析雅浦海沟中底栖生物群落的食物来源和营养级，本研究分析了雅浦海沟真光层中浮游植物和浮游动物、海底沉积物和巨型底栖生物（海绵、海参、海蛇尾、海星、海葵和钩虾）中的碳、氮稳定同位素组成。研究发现雅浦海沟真光层中的浮游植物和浮游动物δ13C值[（-22.8±0.4）‰和（-21.8±0.8）‰]和δ15N值[（5.4±0.4）‰和（6.8±0.2）‰]与巨型底栖生物的δ13C值（-20.1‰~-16.8‰）和δ15N值（11.9‰~17.9‰）的差异超过了一个营养级，表明作为底栖生物的初始食物来源的浮游植物和浮游动物在向下输送的过程中经历了食物链传递和细菌的降解。巨型底栖生物的δ15N和δ13C值之间无显著的相关性，此外不同物种之间营养级也存在明显差异，表现为海绵的营养级相对较高（3.4~4.7），海参（3.3~3.6）、海蛇尾（3.4~3.5）和海星（3.2~3.7）的营养级较为接近，钩虾（2.9~3.3）和海葵（3.1）的营养级则相对略低，反映了底栖生物不同物种之间食物来源的多样化。  相似文献   

江苏重点海域绿潮漂移扩散数值模拟   总被引：1，自引：0，他引：1  

吉会峰  刘吉堂  莫旭冬  高鑫鑫  杨波 《海洋科学》2018,42(5):82-91

江苏海域是绿潮灾害的多发海域,本文利用MIKE3模型建立了江苏辐射沙洲重点海域三维水动力模型,并采用实测资料对模型进行验证和率定;在水动力模型的基础上建立绿潮漂移扩散模型,对江苏海域绿潮漂移路径进行了模拟并与卫星遥感监测的结果进行对比。对比结果表明,模型24 h和48 h模拟结果与卫星遥感图像分析结果较吻合,模型能为江苏海域绿潮的预警预报提供一定参考。  相似文献   

Numerical study of sand scour with a modified Eulerian model based on incipient motion theory     

Qingqing Yuan  Min Zhao  Tong Ge 《Marine Georesources & Geotechnology》2018,36(7):818-826

Application of the standard Eulerian model to simulations of sand scour results in unrealistic phenomena. Therefore, the present work develops a modified Eulerian model based on sand incipient motion theory. The modified model is applied for simulating a two-dimensional single vertical jet and a moving planar jet. The simulation results generally demonstrate fairly good agreement with published results of scour profiles and the velocity contours of the water and sand phases. In addition, equations to describe self-similar scour profiles for the moving planar jet cases are given. The results demonstrate that the modified model efficiently and accurately simulates the two-dimensional sand scour produced by jets, particularly for the moving jet cases.  相似文献   

Comparative analysis on microbial community associated with different gastrointestinal regions of wild northern snakehead Channa argus Cantor, 1842     

苗淑彦  赵臣泽  朱锦裕  潘明珠 《中国海洋湖沼学报》2018,36(2):450-456

Microbial communities in different gastrointestinal regions(stomach, foregut, midgut, and hindgut) of the northern snakehead C hanna argus(Cantor, 1842) were compared by polymerase chain reaction and partial 16 S r DNA sequencing. A total of 194, 140, 212, and 122 OTUs were detected in the stomach, foregut, midgut, and hindgut, respectively. Significant dif ferences were found in the Sobs, ACE, Shannon, and Simpson indices among samples(P 0.05). The gastrointestinal microbial community of C. argus consisted predominantly of Proteobacteria with either H alomonas, Shewanella, Plesiomonas, or Sphingomonas. Fusobacteria, Firmicutes, and Bacteroidetes also existed in the gastrointestinal tracts. However, significant diff erences were found in the compositions of microbial community among the four regions( P 0.05). Cyanobacteria and Spirochetes were significantly higher in the midgut and hindgut( P 0.05). Fusobacteria and Firmicutes were dominant in the hindgut and foregut, respectively(P 0.05). Proteobacteria was the lowest in the hindgut( P 0.05). At genus level, C etobacterium and Plesiomonas were significantly higher in the hindgut than in the other three samples( P 0.05). Clostridium and Prevotella were the highest in the midgut(P 0.05). Halomonas, Shewanella, and S phingomonas were the highest in the foregut( P 0.05). Paracoccus and Vibrio were the highest in the stomach. Several genera were only detected in certain regions, as follows: stomach, P aracoccus and Vibrio; foregut, Halomonas, Shewanella, and Sphingomonas; midgut, Clostridium and Prevotella; and hindgut, C etobacterium and Plesiomonas( P 0.05). At the species level, A cinetobacter rhizosphaerae was only detected in the stomach. P revotella copri and Clostridium perfring were not detected in the foregut and midgut, respectively, whereas Prevotella copri and Faecalibacterium pra were not detected in the hindgut. These findings provide valuable information on the microbial community in each gastrointestinal region of C. argus. Moreover, this study indicated that microbial community was not only related to rearing environment but also to the physico-chemical characteristics of each gastrointestinal region.  相似文献   

西北太平洋深海海山的一种蛇尾新记录     

张东声  鹿博  王春生  蒂莫西&#;奥哈拉 《海洋学报(英文版)》2018,37(10):180-184

Ophioleila elegans是一种非常少见的蛇尾。2014年大洋35航次中利用“蛟龙”号载人潜器在西北太平洋麦哲伦海山链的采薇平定海山水深1660m处采集到2株该种标本。该种首次发现于夏威夷海山相似的生境当中，本次采集到的样品是继首次发现之后的再次公开报道。本文中对该种的形态学特征，如腕部骨骼等，进行了更加详细的研究，同时基于COI序列进行系统发育分析。形态和系统发育分析的结果都表明，Ophioleila属与辐蛇尾科更加接近。  相似文献   

Regional Characteristics and Causes of Haze Events in Northeast China     

Weiwei Chen  Shichun Zhang  Quansong Tong  Xuelei Zhang  Hongmei Zhao  Siqi Ma  Aijun Xiu  Yuexin He 《中国地理科学(英文版)》2018,28(5):836-850

Northeast China experiences severe atmospheric pollution, with an increasing occurrence of heavy haze episodes. However, the underlying forces driving haze formation during different seasons are poorly understood. In this study, we explored the spatio-temporal characteristics and causes of haze events in Northeast China by combining a range of data sources(i.e., ground monitoring, satellite-based products, and meteorological products). It was found that the ‘Shenyang-Changchun-Harbin(SCH)'city belt was the most polluted area in the region on an annual scale. The spatial distribution of air quality index(AQI) values had a clear seasonality, with the worst pollution occurring in winter, an approximately oval-shaped polluted area around western Jilin Province in spring, and the best air quality occurring in summer and most of the autumn. The three periods that typically experienced intense haze events were Period I from mid-October to mid-November(i.e., late autumn and early winter), Period II from late-December to February(i.e., the coldest time in winter), and Period III from April to mid-May(i.e., spring). During Period I, strong PM_(2.5) emissions from seasonal crop residue burning and coal burning for winter heating were the dominant reasons for the occurrence of extreme haze events(AQI 300). Period II had frequent heavy haze events(200 AQI 300) in the coldest months of January and February, which were due to high PM_(2.5) emissions from coal burning and vehicle fuel consumption, a lower atmospheric boundary layer, and stagnant atmospheric conditions. Haze events in Period III, with high PM_(10) concentrations, were primarily caused by the regional transportation of windblown dust from degraded grassland in central Inner Mongolia and bare soil in western Jilin Province. Local agricultural tilling could also release PM_(10) and enhance the levels of windblown dust from tilled soil. Better control of coal burning, fuel consumption, and crop residue burning in winter and autumn is urgently needed to address the haze problem in Northeast China.  相似文献   

BIM与SuperMap GIS数据集成技术     

王博  李濛  冯振华  钟耳顺  王少华  蔡文文 《地理信息世界》2018,(1):120-124,129

现代社会大型复杂建设工程越来越多,室内3D GIS应用需求旺盛,但海量室内3D数据的缺乏成为室内GIS应用瓶颈。建筑信息模型(Building Information Models,BIM)提供丰富的建筑空间几何和语义信息,可为GIS所用。BIM与GIS数据集成技术成为国内外研究热点。本文从GIS应用的角度出发,通过分析BIM与GIS在数据标准和几何、语义表达方面的差异,提出BIM与SuperMap GIS 8C软件的数据集成技术,并实现了BIM在SuperMap GIS中的高性能空间分析与可视化。本文的研究有助于扩展SuperMap GIS的应用领域至室内空间,实现室外到室内、城市宏观到建筑微观的一体化应用,满足大型复杂室内场所的应急救援、导航与位置服务需求,服务于智慧城市建设。  相似文献   

五味安神颗粒干法制粒工艺优化研究          下载免费PDF全文

黄生武  汤波  朱立华 《应用海洋学学报》2018,34(9):173-175

目的：提高五味安神颗粒的产品质量，优化制备工艺。方法：通过单因素试验优化颗粒的制备工艺，以辊压制粒后的干颗粒粒径分布为考核指标，对影响干压制粒的轧辊压力、轧辊转速和物料的传送速度进行考察。结果：优化后的干法制粒工艺中间体颗粒得率达到64%，工艺参数为螺旋转速120rpm，轧辊转速26rpm，轧辊间隙0.8mm，整粒转速150rpm，工作压力120bar，整粒孔径1.5mm。结论：干法制粒工艺制备的中间体颗粒符合质量要求。  相似文献   

环渤海地区海洋经济增长质量空间溢出效应研究   总被引：4，自引：2，他引：2  

李博  田闯  金翠  史钊源 《地理科学》2020,40(8):1266-1275

海洋经济向质量效益型转变是建设海洋强国的新要求。通过构建海洋经济?地理距离空间权重矩阵对2000—2014年环渤海地区17个沿海地级市海洋经济增长质量主体的空间交互作用及空间效应进行研究；借助空间计量模型对海洋经济增长质量空间效应影响因素进行甄别。研究表明：① 环渤海地区海洋经济增长质量主体呈显著空间相关性，存在空间交互作用；② 海洋经济增长质量存在空间溢出的正反馈效应。影响因素中对环渤海地区海洋经济增长质量的直接贡献强度排序为：海洋环境>海洋产业>海洋人才>海洋资本>海洋科技，对其他地区溢出效应影响的排序为：海洋基建>海洋人才>海洋资本。研究为环渤海地区海洋政策制定提供一定参考依据。  相似文献