Numerical investigation of the control factors driving Zhe-Min Coastal Current

During the northeast monsoon season, Zhe-Min Coastal Current(ZMCC) travels along the Chinese mainland coast and carries fresh, cold, and eutrophic water. ZMCC is significantly important for the hydrodynamic processes and marine ecosystems along its path. Thus, this bottom-trapped plume deserves to be further discussed in terms of the major driving factor, for which different opinions exist. For this purpose, in this study, a high resolution Semi-implicit Cross-scale Hydroscience Integrated Syste...     

壳聚糖/纳米铜复合微球的制备及其对刚果红染料的脱色性能

以壳聚糖和CuCl₂·2H₂O为原料,分别采用直接负载法和吸附法成功制备了壳聚糖/纳米铜复合微球,运用傅里叶变换红外光谱(FT-IR)、X-射线衍射(XDR)和扫描电镜(SEM)对催化剂结构进行了表征。以刚果红(CR)染料为目标污染物,评价了催化剂的制备方法、制备条件及氢转移催化反应条件对其催化性能的影响。结果表明,由直接负载法(CS/CuNPs)和吸附法(CS/CuNPs-X)制备的壳聚糖/纳米铜复合微球在CR染料浓度为100 mg/L,催化剂投加量为0.05 g,供氢体浓度为0.05 mol/L的氢转移催化反应条件下,催化反应进行180和60 min时CR脱色率可分别达95.8%和96.8%。CS/CuNPs-X比CS/CuNPs表现了更高的对CR氢转移催化反应的催化速率。两种催化剂催化还原CR染料的反应均符合准一级动力学模型。在连续循环使用10次后,CS/CuNPs和CS/CuNPs-X对CR的脱色率分别为93.9%和89.4%,表明催化剂具有良好的重复使用性能。     

海带褐藻多酚对绿烂海带表面分离的一株细菌的抑菌效果研究

海带苗绿烂病暴发严重威胁海带养殖生产,给海带养殖业造成巨大经济损失.研究发现,海带中的多酚化合物可以抵御海带病害初期病原体侵入.为研究多酚对绿烂海带表面附生菌的抑菌效果,在病烂部位分离出一株细菌,通过16s rRNA基因测序的方法,证实该细菌为小孔芽孢杆菌(Bacillus foraminis).进一步以健康海带为原料...     

北康-曾母盆地中中新世以来层序地层样式特征探讨

开展地震资料解释,分析上超、下超、顶超等地震反射终止关系、不整合面以及沉积趋势,识别出北康-曾母盆地中中新世以来14个三级层序界面。在层序界面内部,通过层序地层内幕结构刻画和原形剖面恢复,并结合地层堆砌方式,在北康-曾母盆地中中新世以来的层序地层内,划分了海进、高位正常海退、强制海退和低位正常海退4种成因单元。通过进一步研究该4种成因单元内地层结构和相分布关系,提出北康-曾母盆地中中新世以来的3种层序地层样式,即陆架边缘富砂型三角洲进积楔、退积型生物礁和陆架边缘富砂-富泥型退积楔,其中,沉积物源供应量充足且可容空间减小时,发育富砂的三角洲进积楔,陆架边缘-斜坡-盆地区域发育含砂深水扇;而可容空间增量远大于沉积物供应量时,发育退积型生物礁和富砂-富泥退积楔,斜坡-盆地区域含砂深水扇欠发育。     

Application research of narrow band Internet of things buoy and surface hydrodynamics monitoring

This paper applies the narrow band Internet of things communication technology to develop a wireless network equipment and communication system, which can quickly set up a network with a radius of 100 km on water surface. A disposable micro buoy based on narrow-band Internet of things and Beidou positioning function is also developed and used to collect surface hydrodynamic data online. In addition, a web-based public service platform is designed for the analysis and visualization of the data collected by buoys. Combined with the satellite remote sensing data, the study carries a series of marine experiments and studies such as sediment deposition tracking and garbage floating tracking.     

The influence of Stokes drift on oil spills: Sanchi oil spill case

Spilled oil floats and travels across the water’s surface under the influence of wind, currents, and wave action. Wave-induced Stokes drift is an important physical process that can affect surface water particles but that is currently absent from oil spill analyses. In this study, two methods are applied to determine the velocity of Stokes drift, the first calculates velocity from the wind-related formula based upon a one-dimensional frequency spectrum, while the second determines velocity directly from the wave model that was based on a two-dimensional spectrum. The experimental results of numerous models indicated that: (1) oil simulations that include the influence of Stokes drift are more accurate than that those do not; (2) for medium and long-term simulations longer than two days or more, Stokes drift is a significant factor that should not be ignored, and its magnitude can reach about 2% of the wind speed; (3) the velocity of Stokes drift is related to the wind but is not linear. Therefore, Stokes drift cannot simply be replaced or substituted by simply increasing the wind drift factor, which can cause errors in oil spill projections; (4) the Stokes drift velocity obtained from the two-dimensional wave spectrum makes the oil spill simulation more accurate.     

大陆岛入海沉积物通量的估算研究

大陆岛入海沉积物通量（Q_s）信息对于精确解译大陆架沉积记录的研究是个重要补充。针对如何估算大陆岛Q_s的科学问题,本文以中国东南部海域的8 227个大陆岛为例,提出了一种基于邻近大陆中小型河流Q_s的经验公式计算大陆岛Q_s的解决方案。该方案在实施时需设置两个假定,即大陆岛的Q_s法则遵循邻近大陆中小河流的Q_s法则和可将1个大陆岛当作1个河流流域计算其Q_s。结果表明：（1）经验公式计算的大陆岛Q_s为其最小估计值;如考虑大陆岛流域的具体情况,实际的Q_s值会稍微增加,但其增幅不超过n^0.13（n为流域数量）;（2）经验公式能获取大陆岛Q_s的大致数量级信息;大陆岛的总面积为4 418.49 km²,对应Q_s的数量级为10⁶ t/a,与邻近大陆中型河流入海通量的数量级相当;（3）在大河河口湾充填阶段完成以前,大陆岛沉积物是内陆架泥质沉积体的主要物源之一。因此,大陆岛入海沉积物会对大陆架沉积体系的形成和演化造成一定程度的影响,需引起研究人员的高度重视。     

湛江湾三维温盐特征季节变化观测分析

利用2017年1−12月的现场观测数据,分析了湛江湾温盐的三维空间结构及季节变化特征。结果表明：(1) 2017年湛江湾各站位年平均温度为23～27℃、盐度为19～27、位势密度为11～17 kg/m³、浮性频率(N²)为7×10⁻⁵～5×10⁻³ s⁻²。浮性频率的垂向结构及水平分布与温度分布类似,而位势密度则与盐度的变化趋势几乎一致;(2)温度季节变化明显,夏季最高,秋季次之,冬季最低,冬夏温差最大达15℃,而盐度季节变化则不大。相较于季节引起的变化,涨落潮对温度以及盐度影响较小。温度跃层夏季最强,10 m处温度最大梯度可达到0.7℃/m,春秋季温跃层抬升至5 m附近,冬季水体上下混合均匀。夏季和秋季存在明显的盐跃层,盐度梯度最大可达到1.1 m⁻¹。跃层上下温盐的季节变化规律一致;(3)水平分布上,从湾顶区、湾颈区、大堤区、浅滩区到湾口区,温度递减,盐度递增,湾顶区和湾口区平均温度差为2.3℃,盐度差为2.7。温盐图分析显示,不同季节水体呈现为不同的温盐条带,湾口区基本为低温、高盐水体,而湾顶区基本为高温、低盐水体,其他区域水体介于上述两者之间。     

Fluid—Structure Interaction of Two-Phase Flow Passing Through 90° Pipe Bend Under Slug Pattern Conditions

China Ocean Engineering - Numerical simulations of evolution characteristics of slug flow across a 90° pipe bend have been carried out to study the fluid—structure interaction response...     

南极菲尔德斯半岛潮间带沉积物细菌的多样性及分离菌产酶测定

摘要:南极菲尔德斯半岛具有多种不同特征的生态地理微环境,如长城科考站、企鹅岛、生物湾与黄金湾流域、半岛南部、碧玉滩等。这些区域因水文地质、动植物分布、人类活动程度等不同而具有明显的生态地理差异。本研究从这些微环境海岸潮间带采集了7份代表性沉积物样品,采用16S rRNA基因高通量测序方法,对其细菌类群的多样性以及环境理化因子的影响进行了比较分析;同时采用常规可培养鉴定方法,对样品的分离菌株产酶状况进行了初步测定。结果表明：整体上看,所有样品的细菌类群主要分布在45门、104纲、442属当中,表现出比较高的多样性。其中,优势菌门Proteobacteria主要分布在半岛南部、碧玉滩和生物湾潮间带沉积物物中,优势菌门Bacteroidetes主要分布在企鹅岛两侧和黄金湾潮间带沉积物,长城站潮间带沉积物的优势门为Firmicutes。相似生态微环境的潮间带沉积物具有不同的优势菌门和纲;而不同生态微环境潮间带沉积物却具相同的优势菌门和纲。有机氮（TON）、NH4+-N、NO3--N、PO43--P、NO2--N含量与企鹅岛两侧、生物湾、黄金湾潮间带沉积物的菌群多样性具有相关性,其中TON对生物湾样品的影响最大,而有机碳（TOC）对所有样品的影响较小。分离菌株的产酶实验表明：在企鹅岛、生物湾、黄金湾等动物频繁出没的潮间带样品中,蕴藏着一批产淀粉酶、酪蛋白酶、脂肪酶、七叶苷酶、过氧化氢酶能力较强菌株,这为今后进一步的应用开发提供了宝贵的低温产酶菌株来源。 关键词: 菲尔德斯半岛; 潮间带沉积物; 细菌类群多样性; 产酶菌株