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1.
In the last few years, scanning electron microscope (SEM) has been widely used to observeand study community structure and succession of the microfouling organisms on various solid surfaces immersed in the sea, polysaccharide components of bacterial slime layer, two-tier microfouling layer structure , metal corrosion products in the attached process and character-istics of attached microorganisms on the coating surfaces. The SEM observations indicated that substrate components exposed to natural seawater are one of the important factors affecting microbial adhesion. The present paper examined the influences of several metal materials, from which ship is usually made on microbial adhesion during the exposure to seawater by the SEM and discussed the material selecting problems from the anti-microfouling point of view.  相似文献   

2.
海水中溶解有机碳(DOC)的测定方法主要有过硫酸盐氧化法;紫外光氧化法和高温氧化法。近年来,随着仪器分析的进步,国外已出现能自动连续测定DOC的商售设备。 Menzel等发展的过硫酸钾氧化法,由于设备简单,容易实施,至今仍为很多人采用。  相似文献   

3.
南海中央盆地热流值的初步分析   总被引:1,自引:0,他引:1  
夏戡原  陈雪 《海洋学报》1981,3(3):434-459
近年来,美国和日本的一些科学家公布了在南海中央盆地海底测得的36个热流值。本文结合我们所作的部分地球物理成果对这些热流数据进行初步分析。南海中央盆地热流值的分布特点有三:1.盆地中部热流值高,边缘较低,海沟(马尼拉海沟)与海槽(巴拉望海槽)处最低;2.热流的最高值(3.63HFU)出现在中央盆地西缘断裂的东侧,沿此北东向大断裂(属岩石圈断裂)的走向,集中出现大于2.5HFU的高值,此种高热流值与大断裂相伴随的现象反映了盆地高热流值与大断裂密切有关;3.盆地中大于2HFU的等值线成北东南西向展布,与构造线的方向一致,但在西沙群岛与中沙群岛的北缘,沿北西西方向,于北纬16°30'附近,序在一稍低的热流带,热流值在1.8—1.99HFU之间。此低热流带将盆地热流值分成两个区。此带以北为北区,以南为南区。北区热流值在1.9—2.46HFU之间;南区热流值较高,为2.11—3.63HFU之间。北区热流等值线为北东偏东方向展布,南区为北东向。为了进一步了解南海热流值的特点,对照了日本海、西菲律宾海、东菲律宾PareceVela海、苏禄海、苏拉威西海等西太洋边缘海的热流值与构造的关系。总的看来,与南海中央盆地类似,这些海盆的热流值大致都为中部高边缘低,最高值大多沿大断裂带或板块扩张轴的延伸方向分布。  相似文献   

4.
The Xisha Islands consist of more than 30 islands. large and small, as well as bars,reefs and shoals. With the exception of Gaojianshi (the Volcanic Rock), they are allcoral reefs. However, little is known about what biotic process has been operating inthe formation of these coral reefs. Some authors suggest that it is mainly due to theprocess of reef-building corals. Others consider that coralline algae (or calcareousalgae) have been rather important in the formation of the reefs. Similarly, disagreementexists on whether there are "algal-ridges" on the windward sea side. Some are of theopinion that there are "algal-ridges" everywhere in Xisha Islands, but others assertdefinitely that there are no "algal-ridges" in Xisha Islands.  相似文献   

5.
A method for determination of malathion in natural water by cathodic stripping voltammetry using mercury film electrode is suggested in this paper. The method is based on the quantitativeformation of group generated by malathion as a result of elimination reaction inthe ethanol solution of sodium hydroxide. The group is similar to sulphide in electrochemical properties, and can be determined by cathodic stripping voltammetry. Interference from inorganic sulphide is prevented by the addition of Hg (NO3)2. This method has been applied to the determination of residual malathion in natural water (e. g. the sea, rivers, lakes, etc.). The waveheight is directly proportional to the malathion concentration within the range 5×10-9 - 1×10-7 mol/L. The method is simple and rapid, and the results of water sample determination is quite in accord with those of Gas Chromatograph.  相似文献   

6.
I. INTRODUCTION AHP resin is a new type of adsorbent and has been studied by the units concernedfor several years. There is little report about this work so far. AHP resin was synthesizedin aqueous phase with tetra-ethylene pentamine (TEPA), epichlorohydrin (ECH) andC-reagent as raw materials, and basic zinc carbonate (P_Z_n) and rubber solvent oil (120Gasoline) as pore-forming material. Compared with the technique of the amorphous lumpresin and that of the resin synthesized in oil phase, the new technique of resin synthesizedin aqueous phase manifests many advantages, such as raising the capacity of uranium-adsorption of the resin, simplifying the after-treatment process, reducing the cost, etc. Sea water, in which all kinds of cation and anion exist, is a system of electrolytes,and the concentrations of many ions are higher than the concentration of uranium for  相似文献   

7.
In this paper, a systematic discussion based on the theory proposed in the preceding paper is given for such breaking characteristics on sloping beaches as breaking depths and breaker heights. Through introducing two empirical constants and considering the complicatedness of the subject studied, the final results are in good agreement with observations. Further experimental verification and theoretical study are necessary.  相似文献   

8.
本文研究了用Aliguat-336萃取,无焰原子吸收分光光度法测定海水中不同价态铬的方法。该方法有较好的精密度,变动系数为6.0%。回收率在80%左右,其特征量为6.3×10~(14)g,较好地应用于海水中不同价态铬的测定。  相似文献   

9.
A PARAMETRIC MODEL FOR THERMAL STRUCTURE FEATURES OF THE OCEAN UPPER LAYER   总被引:1,自引:0,他引:1  
Based on the non-dimensional general function for the thermal structure features presented by S. A. Kitaigorodsky et al. (1963, 1965)[10,11]. this paper tries to establish semi-empirical and semi-theoretical models bfor the thickness of the upper homogeneous layer of the ocean, thermocline intensity and lower oundary depth of thermocline by consecutive observations from 159 stations in the Bohai Sea,Huanghai Sea and East China Sea in the warm half of the years from 1957 to 1964 and the heat budget at the sea surface computed with the simplified computing formulae proposed by Wang (1983)[22]. This model indicates the main factors forming the thermal structure features in the upper layer of the ocean and their function. With the model, one can directly use the sea surface temperature, air temperature and wind speed to compute the thermal feature in the upper layer of the ocean.  相似文献   

10.
It has been well documented that natural marine Ariake clays are sensitive clays. In this study, extensive data of marine Ariake clays are obtained to investigate the gravitational compression behavior for sensitive clays. Analysis results indicate that the compression behavior of remolded Ariake clays is not different from that of other remolded/reconstituted soils. But natural Ariake clays do not follow the gravitational compression pattern reported by Skempton (1970) Skempton, A. W. 1970. “The consolidation of clays by gravitational compaction”. In Q. J. Geol. Soc 373411.  [Google Scholar] for natural sedimentary soils. At a given value of effective overburden pressure, the void ratios of natural Ariake clays are almost independent of liquid limits. Most natural Ariake clays lie above the sedimentation compression line proposed by Burland (1990) Burland, J. B. 1990. On the compressibility and shear strength of natural clays. Gèotechnique, 40: 329378. [Crossref], [Web of Science ®] [Google Scholar]. When the liquid limit is larger than 90% and the ratio of natural water content over liquid limit ranges 0.8–1.1, the natural Ariake clays lie around the sedimentation compression line. In addition, the natural Ariake clay with higher value of the ratio of natural water content over liquid limit lies above the natural Ariake clay with lower value of the ratio of natural water content over liquid limit. Salt removal is the most probable cause for such a phenomenon.  相似文献   

11.
This case study demonstrates how natural heterogeneities of formation and injection waters can be applied to a number of production related applications, extending into the mature life of a reservoir. Break-through of injection water, identification and characterisation of production intervals and evaluation of responses to operational events are some of the possible applications during production.The Oseberg Øst oil field in the North Sea represents a complex situation with commingled production from all Brent Group formations. The Sr isotope composition is an excellent parameter for defining the natural baseline of formation water, with a good spatial resolution and vertical stratification. Aquifer water from the Utsira Formation is injected for pressure support, and reinjection of produced water has also been applied since the onset of water production. Utsira Formation water has high Mg, low Ba and low Sr content compared to the reservoir formation waters. Isotopic compositions (δD and 87Sr/86Sr) are also distinct. A non-reactive behaviour of Ba and Sr is verified from binary cross-plots and geochemical modelling. Break-through of injection water could be identified in five production wells based on Ba/Mg ratios. In one of the reservoir compartments (Beta Saddle), water injection points were changed after approximately three years. The Ba/Mg ratio could also identify the second injection water break-through in one of the wells due to an intermediate period of higher formation water content. Since the Sr content in the Utsira water is low, the 87Sr/86Sr ratio is a good natural tracer for formation water movements even at high ratios of injected water. In particular, the vertical stratification of 87Sr/86Sr is useful for quantifying production from different intervals in commingled wells. A methodology for using operational events, such as production allocations or shut-ins, for characterisation of production zones is discussed.  相似文献   

12.
谢义炳  张镡  蒋尚城 《海洋学报》1981,3(4):546-553
There is a close relation between the circulations of the low latitudes over the ocean as well as their. variations and precipitation in China.Rainstorms and droughts which often cause disasters are two extreme cases of precipitation. Therefore it is practically and theoretically significant to forecast both of them. A series of analyses on the predominant rainstorms processes in mid-summer in North China were made from 1975 to 1977[1,2],and the method was used.As a consequence, a preliminary conclusion has been reached.  相似文献   

13.
The importance of the diet as a source of tributyltin (TBT) in Nucella lapillus was studied using [14C]tributyltin chloride. In N. lapillus provided with prelabelled mussels, Mytilus edulis, in labelled water (mean 20·5 ng/litre TBT) the rate of accumulation of total 14C was 2–3 times that in unfed animals. Owing to its degradation in the tissues of both fed and unfed animals, concentrations of [14C]TBT tended to reach a plateau after only 28 days. However, total concentrations of 14C were still increasing after 49 days. Under experimental conditions (15°C, ample food, no disturbance) the diet accounted for about 50% of the body burden of TBT in N. lapillus after 49 days exposure: concentration factors (dry tissue/water) for [14C]TBT in both male and female N. lapillus were similar at about 60 000 in fed and 30 000 in unfed animals. It is concluded that the diet may contribute less than half of the body burden of TBT found in natural populations subjected to life-long exposure.  相似文献   

14.
15.
Since the end of 19th century, large amounts of studies have been made on marinehydromedusae fauna all over the world. According to a preliminary statistical survey,there are about 450 species of marine hydromedusae in the world. The record of marine hydromedusae in the China Sea Areas began in 1879 andaltogether 21 species had been reported fragmentarily until 1940's. Beginning from1950's, the range of investigation had been enlarged to the whole China Sea Areas andthe study had been more systematically carried out. Qiu (1954), Zhou et al (1958),Gao et al (1958, 1962), Xu and Zhang (1964, 1974, 1978), Xu (1965) and Zhang (1977)respectively reported in detail hydromedusae species around China. Kramp (1965) also  相似文献   

16.
保山盆地湖相泥岩微量元素分布与古盐度定量评价   总被引:11,自引:1,他引:10  
于1994—1995年间,在云南保山盆地第三系地层采集泥岩样品,用中子活化分析方法和化学分析方法测定了泥岩的微量元素和氧化物含量;用X-射线衍射(XRD)分析和扫描电镜(SEM)分析方法测试了泥岩的粘土矿物成分和含量;应用科奇和亚当斯理论计算了湖盆古盐度。结果表明,该湖盆羊四段盐度最高达15.70,羊三段盐度为12.79,羊一段盐度为13.35,南林组盐度为13.26。随着沉积介质盐度的增大,微量元素硼(B)、相当硼含量逐渐增大,Sr/Ba,B/Ga比值也逐渐增加,它们之间呈线性正相关关系。  相似文献   

17.
In mammals, the induction of cytochrome P4501A forms by chlorinated dibenzo-p-dioxins, chlorinated dibenzofurans, and halogenated biphenyls is under control of a soluble protein known as the Ah (aromatic hydrocarbon) receptor. Little is known about the presence and properties of the Ah receptor in other vertebrate and invertebrate species. In these studies, we sought evidence for an Ah receptor in the liver or liver-equivalent of 20 species of marine and freshwater animals, using the photoaffinity ligand 2-azido-3-[125I] iodo-7,8-dibromodibenzo-p-dioxin (N3[125I]Br2DD). Specific labeling of cytosolic proteins by N3[125I]Br2DD was observed in seven species of teleost and elasmobranch fish, in PLHC-I fish hepatoma cells, and in beluga whales. No specifically labeled proteins were found in cytosol from two species of agnathan fish nor in any of nine invertebrate species representing eight classes of four phyla. The presence or absence of specifically labeled polypeptides corresponds with the inducibility of cytochrome P4501A and sensitivity to the toxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin and related planar halogenated aromatic hydrocarbons in many of these groups. Thus, Ah receptor function may have arisen early invertebrate evolution and has been conserved from elasmobranch and teleost fish to mammals.  相似文献   

18.
吴冬梅  谢超  罗红宇 《海洋与湖沼》2012,43(6):1266-1271
以肌动球蛋白含量、Ca2+-ATPase酶活性、总巯基活性(T-SH)和活性巯基(A-SH)含量为考察指标,研究了用不同pH的酸性电解水、以不同的时间对凡纳滨对虾进行减菌化处理后,对虾肌肉的生理特性及肌肉品质的变化。结果表明:电解水的酸性越强、处理时间越长,对虾的肌动球蛋白、T-SH和A-SH的含量越低,Ca2+-ATPase的酶活越小。当对虾在pH分别为2.62、3.18、4.06的酸性电解水中处理60min后,肌动球蛋白含量分别损失了98.7%、90.0%、73.7%,Ca2+-ATPase的失活率分别为93.4%、87.8%、84.3%,T-SH含量分别减少了57.8%、42.3%、40.3%,A-SH含量分别减少了77.8%、65.9%、30.7%。说明酸性电解水的减菌化条件对虾肉的生化指标影响显著。  相似文献   

19.
于2009年8月在海南省东寨港、亚龙湾青梅港和三亚河口红树林区,分别采用自行研制的沉积物耗氧量(Sediment oxygen demand,SOD)测定装置,对红树林湿地SOD和相关环境因子进行研究。结果表明,红树林湿地沉积物耗氧主要分为2个阶段,即瞬时耗氧阶段和渐缓耗氧阶段。3个站位的SOD值范围为102.2-157.7mg/(m2·h),其中瞬时耗氧占23.3%-45.5%。SOD与沉积物中的硫化物含量及上覆水中的化学耗氧量(Chemical oxygen demand,COD)、NH4+浓度有显著的相关性。研究结果表明,红树林湿地沉积物能对其上覆水释放有机物并消耗水体中的溶解氧,使水质变差,因此,用红树林湿地处理城市污水可能导致生态恶化。  相似文献   

20.
1. The adsorption action of basic zinc carbonate adsorbent on uranium in natural seawater can be expressed with the following formula of adsorption isotherm:C=k(U*)n = 8.51× 10-1(U*)0.49,where C is the concentration of uranium on adsorbent; U* is content of uranium in natural seawater employed.2. when the quantity of basic zinc carbonate adsorbent (T) is constant, with the increase of natural seawater quantity through the adsorption column (G), also increased are the adsorption content of uranium of the adsorbent (U), the concentration of uranium on the adsorbent (C) and the concentration of residual uranium (C0*) in natural seawater after adsorbing uranium, while the rate of recovery of uranium (R) is decreased. With the increase of (G) the coefficient of distribution (Kd) decreases to a certain value and then a little rises again.  相似文献   

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