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1.
The structure and composition of the test wall in seven species of Bathysiphon, a genus of large, tubular agglutinated foraminifers (Astrorhizacacea), have been studied using high-resolution SEM. In all cases the wall is composed mainly of quartz grains and varying proportions of sponge spicules which, in some species, show a characteristic orientation within the wall. Three species, B. capillare, B. flavidus and B. rufus, have a well-defined, but very thin (1 μm) outer layer consisting of flat-lying or imbricated plate-like mineral grains. Bathysiphon stictus has a less well-defined surface veneer of tiny mineral grains while in B. major the surface layer is composed of dark-grey or dark-brown particles of an indeterminate nature. The test fabric is rather open and, in all species, the intergranular spaces are partly occupied by an organic cement which forms either a meshwork of fine, branching and anastomozing fibres or shorter, column-like strands. All species also have an inner organic test lining. Thus, the basic structure and composition of the test wall is fairly uniform, but some features show interspecific variability. Some incidental observations on the organization of the protoplasmic body are also reported.  相似文献   
2.
《Journal of Natural History》2012,46(5):1427-1435
Six species of solitary ascidian are recorded from 1335–6489 m off the coast of northern Peru. They confirm the wide distribution of species from abyssal basins. Variations occur in the previously described morphology, and in Dicopia hians suggest a relationship with the Corellidae.  相似文献   
3.
载人潜器半物理虚拟仿真系统及其性能分析   总被引:1,自引:1,他引:0  
为了缩短深海载人潜器控制系统的开发周期,测试系统性能,根据载人潜器的自身特点,构建和实现了载人潜器所有传感器、执行器设备模拟,以及潜器在海底实景的运动状态的半物理虚拟仿真系统。首先,以仿真系统的硬件架构和数据流程为基础,重点介绍了潜器设备模拟的软件体系结构;其次,在仿真平台上测试了各种网络数据的传输延迟,分析了其整体性能;最后,得出了潜器控制器设计的时间约束。现阶段整个系统已经开发成功,并投入运行到潜器控制系统的安装调试中。  相似文献   
4.
深海是人类未来的资源宝库,蕴含着丰富的资源,主要包括多金属结核、富钴结壳、天然气水合物、油气等。我国人口众多,矿产资源的人均占有量远低于世界平均水平,资源瓶颈将在未来几十年成为制约我国经济发展的最大瓶颈,所以发展深海采矿产业对我国有着格外重大的意义。但是深海采矿行业技术要求高,资金投入大,风险性也较高,因此为了保障该行业的良性发展,保障国家的能源安全,对深海采矿行业建立起一套完善有效的主体资格管理制度是非常有必要的。通过对确立合理的深海采矿主体资格制度必要性的论述,及对我国深海采矿行业市场准入制度现状及所存在问题的分析,在借鉴外国先进立法经验和制度的基础上,可以对我国深海采矿主体资格制度的建构提出一些设想和建议。  相似文献   
5.
High resolution elemental MD05-2903 from the northern South records in core China Sea were obtained from XRF scanning and grain size and mineral component analyses. The K/Ti curve reveals climate changes since MIS 3 on a millennial scale, representing one of the best such records so far from deep-sea sediments of the South China Sea. When compared our K/Ti record with other climate records from high latitude ice cores and from East Asia stalagmites, variations in the K/Ti record show some typical saw-shaped features of rapid climate changes in the Northern Hemisphere. Grain size analysis reveals a close relationship between variations in K/Ti and in the fine end-member grain size. XRD analysis confirms that high K/Ti layers were dominated by K-rich weathering minerals, especially illite, while low K/Ti layers contain low illite but high abundance of Ti-rich heavy minerals. Therefore, the K/Ti record reflects changes in the input and deposition of fine weathering minerals and heavy minerals in the northern South China Sea region during stadials and interstadials. These elemental changes were largely con- trolled by variations in rainfall, erosion, and fluvial trans- portation induced by East Asia Monsoon.  相似文献   
6.
A collection of Crustacea Isopoda (suborder Asellota) from a 10-year sampling programme in the Rockall Trough, NE Atlantic (54°40′N, 12°15′W) was analysed for evidence of breeding seasonality. No evidence of seasonal activity was found — adults and newly released juveniles were present throughout the year — but there was a strong seasonal pattern for breeding intensity. A significantly higher proportion of females was brooding during the winter months (25%) compared to the summer (5%), and the percentage of females brooding varied significantly with depth. The breeding pattern was synchronized to the seasonal deposition of organic detritus known to occur during the summer in the NE Atlantic. There were more newly released juveniles in samples during the summer than during the winter, with most females appearing to release their young at the time the deposition began. This deposition appears to be a major seasonal factor dominating the life-cycles of most benthic species in the Rockall Trough. Juvenile settlement for a range of taxa (echinoderms, molluscs and crustaceans) occurs while the detritus is present and most species maximize vitellogenesis at this time.  相似文献   
7.
《Journal of Natural History》2012,46(8):1107-1132
Previously unidentified tanaidacean material from the US Albatross cruises 1885–86 revealed a number of new species. Most species belonged to the suborder of Neotanaidomorpha, of which two new species were found. Neotanais gardineri n. sp. is described. The species N.insolitus is transferred to the genus Venusticrus. Additional information of previously described species of Neotanais is given. The existence of a cheliped ischium within the Neotanaidae is noted. A species list for the new material from the Albatross Expedition is given as well as complete keys to the females of the suborder Neotanaidomorpha. Species of the suborder Tanaidomorpha were also found. The new species Collettea wilsoni is described (Family indet). Also found were two undesribed species of Anarthruridae (Anarthrurinae), as well as a large number of Agathotanais ingolfi.  相似文献   
8.
A new species of scavenger amphipod of the genus Stephonyx is described and illustrated. The specimen was caught at 1150 m depth with a modified rectangular lobster trap positioned on the sea bottom in the central Gulf of California, Mexico. The new species is characterised by the absence of eyes; the lateral cephalic lobes medially developed and acute; antennae subequal in length; gnathopod 1 chelate, dactylus simple with three distal stout setae, inner margin sinuous with minute setae; gnathopod 2 subchelate, carpus with ventral margin crenulate, propodus subovate, palm deeply excavate, and dactylus slightly shorter than palm; maxilliped inner plate laceolate, with seven marginal nodular robust setae, distally; telson, each lobe with two dorsal robust setae, distal margin truncated, with one penicillate and two simple setae, in addition to two short spines. Stephonyx californiensis sp. nov. is morphologically similar to S. arabiensis, S talismani, S. laqueus and S. perexcavatus. The new species increases the number of Stephonyx species around the world to 14, with one species inhabiting from the continental shelf to abyssal depths (to 3000 m), 11 species occurring in bathyal depths (201–2000 m), and two other species restricted to abyssal depths (2001–4000 m).

www.zoobank.org/urn:lsid:zoobank.org:pub:346C3B15-E56A-4E17-9C5F-C9FDBB2AED92  相似文献   

9.
该文针对深海海底管缆搜索定位及海底地层地貌勘探任务需求,对已有C3D-SBP拖鱼系统进行升级改造,分别对该设备通信硬件、供电线路、连接电缆、软件源代码、USBL、测线进行改装设计.为配合该升级设备在工程中的应用,分别对作业过程中的原始数据资料判断提取技术、原始数据处理与分析技术、释放与回收技术进行相应调整改进.最终形成了一整套适用于深海海底管缆调查和地层地貌综合调查的应用系统升级改造方案.实际工程应用证明该改造方案可行,并带来直接经济效益和间接经济效益,为同类设备的升级改造与应用推广提供了参考,拓展了深海海底管缆和地层地貌调查的技术手段.  相似文献   
10.
根据海底可视化技术对工作水深和图像清晰度的要求,研制了一套6 000 m级深海摄像系统;并应用该系统进行了基于图像处理的多金属结核的矿产普查分析。深海摄像系统水下拖体包括两路高清摄像机、一路照相机、水下定位装置和传感器,信号通过嵌入式系统压缩经过光电复合缆传输到甲板并显示在上位机软件。通过对图像的灰度化处理、二值化处理和数学形态学处理,完成图像的分割与修正,计算图像中某区域多金属结核的面积;该系统在大洋36航次中获得了成功应用,系统工作稳定、拍摄视频清晰度高,圆满完成深海地质调查任务。  相似文献   
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