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91.
R. J. Capon K. Elsbury M. S. Butler C. C. Lu J. N. A. Hooper J. A. P. Rostas K. J. O'Brien L. -M. Mudge A. T. R. Sim 《Cellular and molecular life sciences : CMLS》1993,49(3):263-264
The Antarctic marine spongeTedania charcoti has been shown to contain extraordinarily high natural concentrations of cadmium and zinc, which have in turn been correlated to the ability of the crude ethanol extract to modulate protein phosphorylation in chicken forebrain and to inhibit the growth of several test bacteria. 相似文献
92.
丁辛 《东华大学学报(英文版)》1993,(1)
Periodic variations of warp tension during a weaving cycle results in corresponding variationsof back rest position.However,the oscillation of back rest,in turn,shows effect on the variation ofdynamic warp tension.As a force transfer medium,warp yarn,with specific dynamic performances,is certainly one of the factors influencing the movement of back rest.In this paper,warp yarn istreated as a viscoelastic medium in studying the dynamic behaviours of back rest.A mathematicalmodel of a back rest system is developed based on the automatic control theory.Several factors arelisted,which show influences on the performances of the back rest system.Analytical work is car-ried out to identify the effects on the frequency response of the back rest systen resulting from vari-ations of such parameters as the modulus of elasticity,of both fast-elastic and slow-elasticdeformations,and viscosity coefficient. 相似文献
93.
94.
我们在整理采于广西和海南的单殖吸虫标本时 ,发现寄生于虎鱼鳃上的指环虫两新种 .并确认二翼指环虫DactylogyrusbialatusWu ,Wang&Jiang ,1 988为棘虎伪指环虫PseudodactylogyrushazeOgawa ,1 984的同物异名 ,且棘虎伪指环虫为中国新记录 .现报道如下 ,新种的模式标本保存于华南师范大学生物系 .1 .钦州指环虫 ,新种Dactylogyrusqinzhouensissp nov .(图 1 -a ,b )图 1 钦州指环虫 ,新种Dactylogyrusqinzhouens… 相似文献
95.
Web Services是实现信息发布的一种软件与通讯技术。提出了Web Services技术与设备故障诊断技术结合的全新思路,将设备的工艺流程、工艺参数、信号特征、故障推理诊断结论等通过软件与通讯的方式实现数据的动态交换和人机界面(HMI)的交互,供用户操作,从而形成网络化的系统信息发布。介绍了Web Services的基本原理和特点,结合国家“十五”计划“八六三”项目课题“网络化、智能化大型旋转机械在线诊断系统”,对在线诊断系统中信息发布的常见内容进行了归纳分类,描述如何采用DELPHI6 Web Services组件,实现网络化、智能化大型旋转机械在线诊断系统的信息发布、查询等功能。 相似文献
96.
GEChendong O.Slaymaker T.F.Pedersen 《科学通报(英文版)》2003,48(21):2357-2361
Pb geochronology and sediment core profiles of organic carbon, total sulfur and organic carbon isotope (d 13C) values were used to reconstruct the local environ-mental history of the Shamei Lagoon, located in the Wan-quan River Estuary, eastern Hainan Island, China. Totalsulfur and d 13C values decreased upwards in the top 30 cm of a sediment core that spanned the last 200 years of deposi-tion. Total sulfur concentration and d 13C values respectively decreased upward from 1.92% to 0.36%, and -20.63?to -23.64? The C/S ratio in the 19th century and earlier was relatively stable in the range of 0.47—0.80, and there was a positive correlation between organic carbon and total sulfur. Since around 1900 AD, the C/S ratio increased rapidly to a maximum of 3.94, but no simple correlation was found be-tween organic carbon and total sulfur during this more re-cent period. These results indicated that before 1800 AD, the lagoon had a fully marine character, and the location of to-day抯 Wanquan River Estuary was an open embayment.From 1800 to 1900, the salinity of Shamei Lagoon decreased noticeably. The amount of seawater which could enter thelagoon decreased gradually as the Yudai spit grew. Today,seawater scarcely affects the lagoon; it is essentially a fresh-water basin. 相似文献
97.
21世纪是海洋的世纪,人类将进入一个全面开发和利用海洋的世纪.青岛海洋旅游近年来取得了一定的进展,但在开发中也存在着很多的问题,针对这些问题提出了解决的对策. 相似文献
98.
Discussion of gas enrichment mechanism and natural gas origin in marine sedimentary basin,China 总被引:4,自引:0,他引:4
《科学通报(英文版)》2007,52(Z1)
There are abundant natural gas resources in Chinese marine sedimentary basin. The exploration hot shots of natural gas are the Palaeozoic marine strata here in recent years, and several large scale gas fields have been discovered. Chinese Palaeozoic high-post matured and coal measure hydrocarbon source rocks are mainly prone to gas generation in the present. This research considered that gas source rocks and TSR are the key cause of gas enrichment of marine strata. High-quality argillaceous and coal measure hydrocarbon rocks are distributed widely in the Palaeozoic marine strata, which have been in highly matured phase in the present. The argillaceous source rock generally contains various sulfates that could accelerate crude oil cracking to gas for TSR occurrence, and coal measure source rock mainly generates gas, so Chinese marine basin gives priority to accumulating gas. Marine strata have not founded oil reservoirs in the Sichuan Basin and Ordos Basin, and they consist mainly of dry gas. Marine natural gases are the mixed gases of oil cracking gas and coal-formed gas in a general way, oil cracking gases contain usually some H2S and CO2. Hydrocarbon carbon isotopes are very complicated, and methane and ethane isotopic values bear apparent reversal caused by thermal evolution and mixing among different genetic types of natural gas. Coal-formed gases are the main component of Chinese marine natural gas. The Upper Permian of the Sichuan Basin and the Carboniferous-Permian of the Ordos Basin coal measure hydrocarbon source rock present large hydrocarbon generation potential, which are the prospecting highlight of marine natural gas hereafter. Oil cracking gas exploration will be paid much attention to in the Tarim Basin because of the lack of coal measure hydrocarbon source rock. 相似文献
99.
概括了近10年来中国海洋化学分析方法研究进展,涉及新技术、新方法在营养盐测定,CO2系统参数分析,痕量有机物分析,化学示踪及同位素分析等方面的应用,并提出了一些不足.本文引用文献56篇,以期为我国海洋化学分析方法的进一步研究和应用提供参考. 相似文献
100.
海水养殖对海域生态系统的影响及其生物修复 总被引:2,自引:0,他引:2
海水养殖业的迅速发展对海域生态系统产生了一系列的严重影响,本文综述了海水养殖带来的营养盐污染及沉积环境变化、药物使用污染、对天然生物的影响等问题.对于海水养殖造成的问题,有着多种治理方式,基于养殖生态系统的生物修复,是近年来新兴的安全有效的修复方法.本文介绍了微生物修复、大型海藻修复、贝-藻修复、人工湿地修复等生物修复方法及其研究进展.随着研究的不断深入,治理的方式也越来越多,但要想从根本上解决海水养殖带来的污染及影响,基于生态系统的海水养殖管理乃是实现海水养殖业可持续发展的关键. 相似文献