A new pelagic Polyconchoecia Xiang,Chen and Du, 2018(Ostracoda:Myodocopa:Halocyprididae) from the South China Sea     

项鹏  王雨  陈瑞祥  叶又茵  王春光  陈小银  林茂 《海洋学报(英文版)》2020,39(4):73-83

Halocyprid ostracods are appreciable part of ostracods floating through virtually everywhere in marine environment.In this study,we describe a new species of genus Polyconchoecia Xiang,Chen and Du,2018,tribe Conchoeciini Chavtur and Angel,2011,family Halocyprididae Dana,1853 from the middle of the South China Sea.Polyconchoecia chenii sp.nov.is very close to P.commixtus Xiang,Chen and Du,2018.But it differs from P.commixtus by the distinctions of locations of major glands of carapace and the characteristics of appendages:more posteriorly situated left asymmetric gland of carapace,no right asymmetric gland;segmented frontal organ;the endopod 2 of the first antenna with a very small seta;a-and c-setae of the first antenna with long end joint have long end joint,the b-and d-setae have no end joint,spinose e-seta without end joint;the e-seta of the second antenna is present;teeth side is distinctive;the setal counts of the mandible,maxilla,fifth limb,and sixth limb are individual.The locations of the major glands on carapace and the characteristics of the first antenna can be the key of the new species.This work is the second discovery of the genus Polyconchoecia from the world.  相似文献   

Experimental Study and Fatigue Analysis of Vortex-Induced Vibration of Umbilical Cable Considering Internal Friction     

Gu  Hong-lu  Guo  Hai-yan  Liu  Zhen  Li  Fu-heng  An  Wan-bo  Li  Peng 《中国海洋工程》2020,34(2):151-161

In order to investigate the effect of internal friction of umbilical cable on its vortex-induced vibration(VIV)responses, the experimental study on VIV of bond umbilical cable(BUC) and un-bond umbilical cable(UBUC) was carried out in an experimental tank. A current generator in the laboratory simulated the uniform current, and the current velocities were observed in real time by using a Doppler Velocimeter. In addition, different sizes of top tension were applied to the umbilical cable model. The VIV responses of the umbilical cable model were measured by using Fiber Bragg grating(FBG) strain sensors. The displacement responses of umbilical cable model were reconstructed based on the experimental strain data processed by modal superposition method. In this paper, the traveling wave characteristics, the spatial-temporal distribution characteristics of frequency and fatigue damage of the BUC and UBUC under VIV are studied. The experimental results show that there are obvious differences between BUC and UBUC in the response characteristics of VIV. The UBUC appears the traveling wave sooner than BUC, but its standing wave characteristics are more obvious than those of BUC at high velocities. Compared with BUC, the spatial-temporal distribution of UBUC frequencies appears wide-band distribution sooner, but has narrower bandwidth in the "lock-in" state. The level of fatigue damage of BUC was approximately the same as that of UBUC.  相似文献   

Experimental and Numerical Study on the Bubble Dynamics near Two-Connected Walls with An Obtuse Angle     

Li  Shi-min  Cui  Pu  Zhang  Shuai  Liu  Wen-tao  Peng  Yu-xiang 《中国海洋工程》2020,34(6):828-839

China Ocean Engineering - This study is concerned with the dynamic characteristics of bubbles near two connected walls (one horizontal and the other inclined with an obtuse angle from the...  相似文献   

獐子岛岩相潮间带大型海藻有机碳含量及δ¹³C值的季节变化特征     

张靖凡  蔡恒江  赵玥茹  陈文翰  胡思琪  刘远  刘长发 《海洋科学》2020,44(2):56-65

为研究岩相潮间带大型海藻有机碳含量及δ~(13)C值的季节变化特征,分别于2016年11月(秋)和2017年2月(冬)、5月(春)、8月(夏)对獐子岛岩相潮间带(39°01′E,122°43′N)的大型海藻进行调查,并对其有机碳含量和δ~(13)C值进行分析。结果表明:共鉴定出大型海藻3门49种,其中红藻门24种,占总数的48.98%;褐藻门17种,占总数的34.69%;绿藻门8种,占总数的16.33%。大型海藻种类数为春季(35种)冬季(24种)=夏季(24种)秋季(23种)。不同种类海藻体内的有机碳含量为15.54%～35.03%,δ~(13)C值在–33.42‰～–7.43‰之间变动。不同季节海藻体内有机碳含量为冬季春季夏季秋季,δ~(13)C值为夏季春季冬季秋季。  相似文献   

“数字海底”--海底数据集成管理与可视化研究     

肖鹏  王悦东  李安龙 《海洋信息》2020,35(1):40-45,51

针对目前"数字海底"建设中存在海底调查数据集成管理与三维可视化表达不足等问题,本文采用GIS技术,以黄河水下三角洲埕北海域为研究对象,利用地理空间数据集成理论与三维建模方法,建立了埕北海域三维海底空间数据库,实现了研究区域地形数据、地层数据、钻孔数据、表层沉积物数据的有效组织管理与可视化,并在此基础上,采用ArcGIS Engine 10.0,结合.NET平台,在Visual Studio 2010开发环境下,利用C#语言进行了二次开发,实现了基于C/S (Client/Server)架构的三维海底虚拟仿真系统的开发,设计了一套面向埕北海域的三维海底虚拟仿真原型系统。  相似文献   

近25年营口浮渡河口湿地景观格局演变过程及驱动因素分析          下载免费PDF全文

闫吉顺  王鹏  张连杰  于永海  刘晓璐 《海洋开发与管理》2020,37(9):76-81

文章通过提取1992年、2007年、2017年三期春季大潮营口浮渡河口遥感影像景观图斑，总结了近25年营口浮渡河口湿地景观格局演变过程，分析了演变的驱动因素。25年间，受人类活动的影响，浮渡河口湿地景观格局出现破碎化现象，系统形成机制遭到破坏，造成河口沙坝-潟湖景观割裂和缩减，湿地生态系统已受到严重影响。对此，文章建议在深入理解浮渡河口湿地景观形成机制、规律及驱动因素的基础上，采取“源头管控”“河岸加固”“构筑物清理”的修复治理措施以恢复其形成机制，使河口湿地生态系统得到修复。  相似文献   

饲料中添加芽孢杆菌组分对凡纳滨对虾幼虾生长、能量代谢和抗WSSV能力的影响     

单洪伟  于鹏  刘宽  于明超  马甡 《中国海洋大学学报(自然科学版)》2020,(1):30-38

以凡纳滨对虾(Litopnnaus vannamei)幼虾为实验动物,在其基础饲料中分别添加芽孢杆菌(Bacillus sp.)胞外蛋白粗提物(1.0%,胞外蛋白组)、胞内多糖粗提物(1.0%,胞内多糖组),以基础饲料为对照组饲料,进行为期28d的养殖实验,探讨芽孢杆菌胞外蛋白和胞内多糖粗提物对幼虾生长、能量代谢及抗病能力的影响。研究表明,芽孢杆菌2种粗提物对凡纳滨对虾的生长和成活率影响不显著(P>0.05)。饲喂2种粗提物影响了凡纳滨对虾肝胰腺和肌肉中能量代谢相关酶活力。胞外蛋白组肝胰腺中磷酸果糖激酶(PFK)、乳酸脱氢酶(LDH)活力在养殖实验前期显著高于对照组(P<0.05),而肌肉中PFK、LDH活力显著低于对照组(P<0.05);胞内多糖组肝胰腺中己糖激酶(HK)活力及肌肉中PFK、LDH活力显著低于对照组(P<0.05)。饲喂2种粗提物均显著提高了凡纳滨对虾肌肉中琥珀酸脱氢酶(SDH)活力和肝胰腺中电子传递系统(ETS)活力(P<0.05),胞外蛋白粗提物对肝胰腺中的SDH活力也有显著的提高作用(P<0.05)。饲喂2种粗提物显著降低了凡纳滨对虾肝胰腺及肌肉组织中脂肪酸合酶(FAS)含量(P<0.05)。此外,饲喂2种粗提物均会显著提高凡纳滨对虾肠道蛋白酶活力(P<0.05),而胞外蛋白粗提物使凡纳滨对虾肠道脂肪酶活力显著降低(P<0.05)。白斑综合征病毒(WSSV)感染后,与对照组相比,胞外蛋白组和胞内多糖组凡纳滨对虾半致死时间分别延长了26.19%和7.14%。根据以上结果推测,芽苞杆菌2种粗提物能够影响凡纳滨对虾能量代谢水平并提高其抗WSSV能力,且二者之间密切相关。  相似文献   

春季西沙永乐龙洞浮游植物的昼夜垂直分布特征     

葛汝平  傅亮  毕乃双  陈畅  刘光兴  庄昀筠  杨作升  范德江  姚鹏  陈洪举 《中国海洋大学学报(自然科学版)》2020,(1):65-73

南海永乐龙洞位于西沙群岛永乐环礁,是迄今为止发现的最深的海洋蓝洞,水文环境及理化因素特殊,90 m以下水体为无氧环境。为研究永乐龙洞浮游植物的群落组成及其昼夜变化,于2017年3月在龙洞、潟湖及外礁坡进行浮游植物样品采集。研究结果表明:龙洞内叶绿素a浓度呈现随深度先增大后减小的趋势,日间浓度最大值层出现在40 m层(0.42μg/L),夜间则出现在20 m层(0.59μg/L)。永乐龙洞微微型浮游植物丰度介于1.1×10^3~5.1×10^4 cells/mL。聚球藻在上层水体占优势(0~20 m),40 m以下水层原绿球藻丰度对微微型浮游植物丰度贡献率最大(90%以上),微微型真核浮游植物丰度在整个水体都较低(除20 m层)。微微型浮游植物昼夜存在明显差异,夜间其丰度最大值层为20 m层,日间则上移至表层。本研究共记录微型和小型浮游植物5门41属55种(含未定种)。其中,硅藻门25属34种、甲藻门12属15种、金藻门1属1种、蓝藻3属、隐藻1属。微型和小型浮游植物丰度介于3.3×10^2~9.8×10^4 cells/L。甲藻丰度对浮游植物总丰度贡献率最大,其次是硅藻,隐藻和蓝藻丰度仅在少数水层占优势。微型和小型浮游植物昼夜变化明显,夜间丰度最大值层为20 m层,日间则出现在40 m层。微微型、微型和小型浮游植物垂直分布与叶绿素a浓度垂直分布一致性高。龙洞浮游植物的种类数和丰度高于潟湖和外礁坡。  相似文献   

A motion planning algorithm for the feed support system of FAST     

姚蕊  姜鹏  孙京海  于东俊  孙纯 《天文和天体物理学研究(英文版)》2020,(5):117-126

The paper relates to a motion planning algorithm for the feed support system of the Five-hundred-meter Aperture Spherical radio Telescope(FAST).To enhance the stability of the feed support system,the start/termination planning segments are adopted with an acceleration and deceleration section.The source switching planning adopts a combination of a line segment and focal segment to realize stable control of the feed support system.Besides,during the observation trajectory,a transition segment which is not used for observation data is planned with a required time.Through an example simulation,a smooth change is realized via the motion planning algorithm and presented in this paper.  相似文献   

湖南仁里超大型钽铌矿床工作进展及找矿思路     

杨世珍  周芳春  李建斌  刘翔  李建康  黄志飚  苏俊男  李鹏 《中国地质调查》2020,7(4):28-36

湖南仁里超大型钽铌矿床钽铌铍矿资源丰富,Ta₂O₅资源量达到了超大型规模,BeO资源量达到了大型规模。为进一步研究湖南仁里超大型钽铌矿床稀有金属的赋存特征、成矿规律及矿产资源综合利用前景,开展了地球化学分析、电子探针、包裹体、同位素测年及可选性试验等研究工作,通过系统梳理仁里超大型钽铌矿床的工作进展,进一步探讨了该矿床的下一步找矿思路。仁里钽铌矿床共(伴)生矿种多,稀有金属综合回收率及矿产资源采选综合利用率高,具有极大的开发利用价值,可作为绿色、环保、无尾矿范例进行高效勘查与开发。仁里矿区钽铌铍矿资源丰富,具有较好的找矿潜力,加大地质勘查资金投入有望取得钽铌铍锂等稀有金属找矿新进展。下一步应对矿区2、3、5、6号主矿脉深部矿体进行控制,力争取得钽铌铍矿找矿突破,同时加强对矿区西部或西南部隐伏锂辉石白云母钠长石伟晶岩的研究工作,力争取得锂辉石白云母钠长石伟晶岩型锂矿找矿突破。  相似文献