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31.
Extremely abundant trace fossils are associated with the deep-sea deposits, especially in turbidite measure and flysch fades. And these trace groups then become the effective indicators to reconstruct the ancient depositional environment and the palaeogeography. This paper focuses on ( i ) the formational features of deep-sea fossil and its assemblage feature, and further recongnizes that the coexistence of the shallow and deep water trace group in a depositional sequences is the identification mark of turbidite sequence; ( ii ) thought and methods using the trace fossil to restore their environmental parameters such as the ancient sea depth, oxygen-bearing condition and sedimentation rate, etc.; (Ⅲ) the application and significance of deep-sea ichnofacies in environment interpretation. 相似文献
32.
采用单菌多次级代谢产物(OSMAC)策略对1株深海放线菌Streptomyces sp.SCSIO 15079进行化学多样性研究。通过在不同盐度、pH值和发酵时长条件下对菌株进行培养调控并筛选出1种适宜发酵条件,分别进行摇床和发酵罐发酵。综合运用正相硅胶柱色谱、十八烷基硅烷(Octadecyl Silance, ODS)反相柱色谱、葡聚糖凝胶柱色谱(Sephadex LH-20)、半制备高效液相色谱(HPLC)等方法,对菌株摇床与发酵罐发酵产物中具有差异的化学成分进行导向分离与纯化,根据核磁数据和文献对比进行化合物结构鉴定。研究结果表明,将Streptomyces sp.SCSIO 15079菌种接种到不添加海盐、pH值为7.2的A培养基中,于28℃、180 r/min摇床发酵7 d,可获得更丰富的代谢产物;经分离鉴定,从摇床发酵产物中得到的9个与发酵罐发酵产物不一样的化合物且均为含氮类化合物,分别为吲哚甲醛(1)、3-羟基吲哚(2)、胸腺嘧啶(3)、尿嘧啶(4)、环-(脯氨酸-苯丙氨酸)二肽(5)、环-(亮氨酸-缬氨酸)二肽(6)、环-(丙氨酸-异亮氨酸)二肽(7)、环-(丙氨酸-缬... 相似文献
33.
应用模糊自适应扩展卡尔曼滤波方法,研究了深海采矿集矿机的定位导航问题。建立了履带式集矿机的状态空间模型,根据长基线定位系统的延时建立了系统的测量方程,提出了基于模糊逻辑的自适应卡尔曼滤波的算法。仿真结果表明:集矿机位置X,Y的新息系列均在±σ的范围内变化,采用该自适应控制算法对Q、R加权的方法所进行的卡尔曼滤波是稳定的、最优的。 相似文献
34.
运用非线性有限元方法,将深海多金属结核开采系统的扬矿硬管、扬矿泵、中间仓和扬矿软管等部分等效为不同属性的管单元,建立了1000m水深海洋试验系统扬矿子系统的有限元分析模型;采用Morison公式计算了水下管线的液动力载荷。基于该模型,进行了长管线系统布放过程的动力学数值模拟,得出了在不同布放操作模式下扬矿子系统的各种动态响应,尤其是软管初始构形的动态形成过程;仿真显示了在某些布放操作模式下,软管缠绕现象发生的全过程。研究结果表明:集矿机着底后,在下放硬管的同时,应通过集矿机的运动使软管尽早地形成马鞍形,以有效地消除缠绕现象。 相似文献
35.
不同倾角深潜器观察窗应力分析计算方法与比较 总被引:1,自引:0,他引:1
深海装备的耐压开口结构设计,是深海探测装备研制过程中的关键技术之一。开口结构观察窗的受力与变形是设计开口结构的基础。文中研究推导了观察窗应力理论公式,作不同倾角情况下的比较,并进行了相关数值计算。 相似文献
36.
结合前人经验,以预热杀菌条件、真空浓缩温度、深海鱼油添加量、鱼油添加时机四个因素分别进行单因素实验,再对四个因素进行三水平正交试验,并通过测定深海鱼油炼乳产品中干物质、脂类、蛋白质等的百分含量及产品的黏度、感官评分,得出深海鱼油炼乳的最佳生产工艺.试验结果显示深海鱼油炼乳的最佳工艺为深海鱼油添加量0.4%,真空浓缩前添... 相似文献
37.
《Journal of Natural History》2012,46(3):811-821
The number of halacarid genera and the approximate number of species in deep and shallow waters are listed, together with the halacarid species recorded from depths of over 1000 m. The vertical and horizontal distribution of genera are discussed, as well as morphological adaptions to life in the abyss. Eurybathic species are rare, and endemic deep-sea genera presumably do not exist. Algibiont and arenicolous genera have not been found in the abyss. Striking morphological features such as long legs, epimeral and anal protuberances, and dense coatings with cuticular filaments are independent of water depth and hydrostatic pressure, but correlate with life in very soft sediments. The deep-sea species, Lohmannella cygna nov. spec., is described. 相似文献
38.
《Journal of Natural History》2012,46(6):1591-1621
The tanaidacean tribe Agathotanaini, which was formerly the family Agathotanaidae, is well-represented in the Rockall Trough and Bay of Biscay areas of the North-east Atlantic. Five species have been recorded from depths of 1160–4829 m. Agathotanais ingolfi is the most numerous and one of the most widely distributed tanaidacean species in the region, and is often predominant in epibenthic sled samples from 1500–2500 m. Less numerous and frequent are three new species of Paragathotanais: P. nanus, P. robustus and P. gracilis. The first two are bathyal in distribution, and the last is abyssal. A new monospecific genus is established for Metagathotanais insulcatus, which has been recorded from the deepest part of the study region (4600–4800 m). Males of this tribe are characterized by their rigid pleopods bearing short terminal setae, and are otherwise very similar to the females. A key is provided for the identification of agathotanaids from the North-east Atlantic, including Agathotanais hanseni, and the genera Allodaposia and Paranarthrura, which should also be classified in the Agathotanaini. 相似文献
39.
针对真实深海采矿环境下实时微地形超声探测声信号获取难的问题,设计并建立了一套能模拟真实深海采矿混响环境的超声探测实验系统.在对螺旋采掘头结构简化的基础上,利用Fluent模拟了螺旋采掘头与多组叶轮模型对水下流场的影响,对二者所得的水下流场进行比较后,确定所选叶轮模型能较好地反映真实采矿环境.随后针对叶轮模型,实验测量了泥沙垂向浓度分布,验证了设计模型的正确性.最后进行超声探测实验,结果表明,悬浮泥沙不仅对声波产生黏滞和吸收,而且会产生严重的混响干扰,通过该超声探测系统的时间增益补偿,可有效抑制混响干扰,增加目标检测概率.本项研究为深海采矿混响环境下的超声微地形探测提供了研究基础. 相似文献
40.
SUNXiangjun LUOYunli CHENHuaicheng 《科学通报(英文版)》2003,48(20):2155-2164
This paper briefly presents the progress of deep-sea pollen research in China since the beginning of ninetieths of the last Century. All the deep-sea pollen contri-butions mainly come from the South China Sea (SCS) and the East China Sea (ECS). The German-Chinese joint cruise (Sonne 95) and ODP 184 cruise initiated by Chinese scientists in the SCS provided excellent material for the deep-sea pollen research. So far a number of pollen results of 20-30 ka and million years from the SCS have been published. A couple of deep-sea pollen records from Okinawa Through of the ECS also came out. The high resolution pollen records obtained from the continuous deposits with high sedimentation rates and reliable age control of the deep-sea sediments provided a high time resolution history (hundred to millennial scales) of vegetation, environment and monsoon evolution of the pollen source areas (southern China and Japan). Spectral analysis of deep-sea pollen records from the SCS discovered orbital (100, 41, 23, 10 ka) and suborbital cyclicities(Heinrich and Dansgaard/Oscheger-O/D events) in the vegetation changes. Moreover, cross spectral analysis showed that the trend of vegetation changes in northern SCS was regulated mainly by changes of the ice volume in the Northern Hemisphere. The pollen record of the last 20 ka from the Okinawa Through of the ECS indicates that the marine environmental change lagged that on the terrestrail by about 1000 year. The asynchronous environmental changes between land and sea were probably caused by the time difference in thermohaline circulation. This study underscored the role of the deep-sea plant fossils as a bridge across the land and sea. 相似文献