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1.
电连接模拟法十年腐蚀试验研究 总被引：2，自引：0，他引：2
在开发海洋所需要的设施中，例如海上采油平台，海上输油码头，海底管线，海上观察测量仪器，海上运输船舶等大都使用钢材来制造。但是由于海水是一种强电介质溶液，使得钢材在海洋环境中遭受着严重腐蚀，这直接影响着海上设施的使用寿命。为了研究钢铁本身的耐腐蚀性能，腐蚀试验方法越来越被腐蚀工作者所重视。即用什么样的腐蚀试验方法来比较、评定所研制钢种的耐腐蚀性能是一项重要工作。室内的电化学测试及加速腐蚀试验等方法为海洋用钢的研制起到了积极作用，它可以较快地对钢铁的耐腐蚀性能进行相对评定［１６，２０，２１］，但有些… 相似文献
2.
海洋构筑物在海洋环境中的腐蚀是相当严重的。从腐蚀的角度，一般都把钢铁设施在海洋环境中的腐蚀分为５个区带［１～５］。即海洋大气区、浪花飞溅区、海水潮差区、海水全浸区、海底泥土区、钢铁设施在各区带的腐蚀情况也不相同。根据各区带腐蚀的轻重情况，分别采取适合于各区带的防蚀措施，以延长海洋设施的使用寿命，这就需要外海的长尺挂样试验。外海的长尺挂样试验需要大量的人力、物力，工作量大，不便于随时观察和测试，周期较长。由于狂风暴雨的袭击，试样很容易丢失，试样一丢失，工作也就前功尽弃。根据以上的种种情况，作者精心… 相似文献
3.
钢材在潮差区和全浸区的腐蚀行为 总被引：3，自引：0，他引：3
海水是一种含有大量盐类的强电解质溶液,它对海洋环境中的钢铁腐蚀极为严重。人们一般把海洋腐蚀环境划分为五个区带:1.海洋大气区;2.浪花飞溅区;3.潮差区;4.海水全浸区;5.海底泥土区等。从而针对不同的腐蚀环境选择具有不同耐蚀性能的材料;根据腐蚀严重性的不同,分别采取适合于各区带的防腐蚀措施以延长海洋钢铁设施的使用寿命。当前国内在筛选耐蚀性海洋用钢材时,有的采用分别挂片的方法,即把试验钢种的小试片分别悬挂于大气区、潮差区和全浸区。实验结果是 相似文献
4.
随着我国海洋开发事业的发展,港口、码头、石油平台等海上设施大量兴建。外加电流阴极保护作为防止海上钢铁构筑物腐蚀的有效措施,日益被广泛采用。阳极材料是外加电流阴极保护系统的核心部件,国内外很多学者都 相似文献
5.
铜及其合金不仅具有一定的抗海水腐蚀性能,也具有一定的防海生物附着性能,同时多数铜合金在海洋环境中的应力腐蚀敏感性较小,所以铜合金是海洋开发中较为理想的材料之一。因而,世界许多国家对铜合金进行了大量海港挂片试验,积累了较系统的资料。我国生产的铜合金在海上进行试验的资料尚待丰富完整。我们选用了15种铜合金和一种镍铜合金(蒙乃尔),在湛江港进行了一年的全浸试验,结果报告如下。 相似文献
6.
海洋腐蚀作为一门应用性较强的多学科交叉的新兴边缘科学 ,在制订科研发展战略 ,在实际的科研选题操作中 ,应该考虑如下一些基本原则。１需要性原则选题应满足当前社会发展的需要性原则。所谓需要性原则是指选定的研究课题必须着眼于社会实践的需要或科学本身发展的需要［５］。海洋资源的开发利用离不开海上基础设施建设 ,一般设施建设都要经过设计阶段 ,其中防腐蚀设计是保证工程设施使用寿命的重要步骤 ,这些相关的设计参数来源于海洋腐蚀环境因素调查和工程材料在海洋环境中的腐蚀破坏规律的研究成果。海洋腐蚀环境因子大体上可分为三类… 相似文献
7.
钢在海洋飞溅带的腐蚀与防护 总被引：3，自引：0，他引：3
人们所说的钢铁结构在海洋环境中腐蚀严重，只是一个总概念。因为海洋环境共有海洋大气带、海洋飞溅带、海水潮差带、海水全浸带和海泥带５个区带。而钢铁的腐蚀行为在各带中有很大差异（如图１所示）。图中数据为第一作者及侯文泰在湛江麻斜岛海区中暴露试验２ａ所得。可见海洋飞溅带才是钢铁构件在海洋环境中受到腐蚀最为严重的区带。目前，人们对解决海洋环境中其他各区带的腐蚀问题，都已经有许多成功的方法和国际标准。但对海洋飞溅带的防护问题却一直为人们所关注，国内外尚无飞溅带腐蚀试验和防护的标准，也未有一套完整的、成熟可靠… 相似文献
8.
受腐蚀钢筋混凝土结构力学性能研究现状 总被引：5，自引：1，他引：5
在总结近年来国内外大量研究成果的基础上，对受腐蚀钢筋混凝土结构的力学性能进行了论述，同时针对海洋环境腐蚀的特点，提出了海洋环境下结构力学性能方面应该研究的课题。为海洋腐蚀环境下钢筋混凝土结构的耐久性设计和使用寿命评估提供参考。 相似文献
9.
随着海洋开发和交通运输事业的迅速发展,海上钢铁构筑物和大型船只日益增多,这就需要提供大量的耐海水腐蚀低合金高强度钢板,而目前我国这类耐海水腐蚀的结构材料几乎全靠进口。近十多年来,我国也在发展耐海 相似文献
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11.
This study revealed a high positive correlation between rainfall in Korea during September and the trade wind (TW)/Arctic Oscillation (AO) index in May that combines two climate factors, low-level TWs and the AO. This correlation was identified on the basis of the difference in the 850 hPa streamline analysis between the positive and negative phases selected using the combined TW/AO index. In May, the spatial pattern of the anomalous pressure systems is similar to that in the positive AO phase. These anomalous pressure systems continue in June to August (JJA) and September, but the overall spatial distribution shifts a little to the south. Particularly in September, a huge anomalous anticyclone centered over the southeast seas of Japan strengthens in most of the western north Pacific region and supplies a large volume of warm and humid air to the region near Korea. This characteristic is confirmed by the facts that during the positive TW/AO phase, the subtropical western north Pacific high (SWNPH) is more developed to the north and that the continuous positioning of the upper troposphere jet over Korea from May to September strengthens the anomalous upward flow, bringing warm and humid air to all layers. These factors contribute to increasing September rainfall in Korea during the positive TW/AO phase. Because the SWNPH develops more to the north in the positive phase, tropical cyclones tend to make landfall in Korea frequently, which also plays a positive role in increasing September rainfall in Korea.The above features are also reflected by the differences in average rainfall between the six years that had the highest May Ni o 3.4 indices (El Ni o phase) and the six years that had the lowest May Ni o 3.4 indices (La Ni a phase). 相似文献
12.
《Deep Sea Research Part I: Oceanographic Research Papers》2002,49(6):971-990
Time-series measurements of particulate organic carbon (POC) and particulate nitrogen (PN) fluxes, sediment community composition, and sediment community oxygen consumption (SCOC) were made at the Hawaii Ocean Time-series station (Sta. ALOHA, 4730 m depth) between December 1997 and January 1999. POC and PN fluxes, estimated from sediment trap collections made at 4000 m depth (730 m above bottom), peaked in late August and early September 1998. SCOC was measured in situ using a free vehicle grab respirometer that also recovered sediments for chemical and biological analyses on six cruises during the 1-year study. Surface sediment organic carbon, total nitrogen and phaeopigments significantly increased in September, corresponding to the pulses in particulate matter fluxes. Bacterial abundance in the surface sediment was highest in September with a subsurface high in November. Sediment macrofauna were numerically dominated by agglutinating Foraminifera fragments with highest density in September. Metazoan abundance, dominated by nematodes was also highest in September. SCOC significantly increased from a low in February to a high in September. POC and PN fluxes at 730 m above bottom were significantly correlated with SCOC with a lag time of ⩽14 days, linking pelagic food supply with benthic processes in the oligotrophic North Pacific gyre. The annual supply of POC into the abyss compared to the estimated annual demand by the sediment community (POC:SCOC) indicates that only 65% of the food demand is met by the supply of organic carbon. 相似文献
13.
Recent investigation suggests that volume transport through the Tsushima/Korea Strait often has double peaks during the summer
to autumn period with decreasing transport in September. The satellite-observed wind changes from weak northwestward (across-strait)
in summer to strong southwestward (along-strait) in early autumn (September) in the strait. Such a strong along-strait wind
is related to tropical cyclones, which frequently pass through the East China Sea in September. The effect of the along-strait
wind component on the transport variation is examined using a three-dimensional numerical model. The simulated volume transport
through the Tsushima/Korea Strait shows realistic seasonal and intra-seasonal variations. According to sensitivity experiments
on local winds, the transport variations in September are mainly generated by strong along-strait (southwestward) wind rather
than weak across-strait wind. The strait transport responds to the along-strait wind (southeastward), which produces a sea
level increase along the Korean coast, resulting in the geostrophic balance across the strait. The transport minimum through
the Tsushima/Korea Strait in September can be determined by the combination of the across-strait geostrophic and along-strait
ageostrophic balances.
The Editor-in-Chief does not recommend the usage of the term “Japan/East Sea” in place of “Sea of Japan”. 相似文献
14.
《Oceanologica Acta》2002,25(1):39-49
In June and September of 1999, a LISST-100 in situ laser diffraction particle sizer was used to analyse the temporal and spatial variation of the beam attenuation coefficient, the in situ median particle (aggregate) diameter and the median volume concentration of suspended matter in two Danish coastal water bodies. One of the study sites was generally exposed to wind, while the other was quite sheltered. Measurements of the mass concentration of total suspended matter and chl a were made simultaneously. The in situ median effective density, settling velocity and vertical flux of the suspended matter are computed. Results demonstrate that in September, the in situ median aggregate diameter, settling velocity and vertical flux was smaller (by a factor of up to 16) and the concentration higher (by a factor of up to almost two) than in June. This is attributed to varying degrees of turbulence in the water in the weeks preceding the field work, causing aggregates to break up (lowering in situ aggregate diameter and settling velocity) and sediment to be resuspended (increasing concentration) in September. The fractal dimension of the suspended aggregates is estimated. The fractal dimension is found to increase from June to September at both study sites, supporting the notion of aggregate break-up in September due to turbulence in the upper part of the water column. An algae bloom occurred at the sheltered study site in September. In situ particle size spectra from this site demonstrated increasing aggregate sizes towards the bottom. It is suggested, that the increase in size is due to biologically induced aggregation, causing large aggregates to settle out of the upper part of the water column, leaving finer particles and aggregates behind. 相似文献
15.
Bianchi TS Cook RL Perdue EM Kolic PE Green N Zhang Y Smith RW Kolker AS Ameen A King G Ojwang LM Schneider CL Normand AE Hetland R 《Marine environmental research》2011,72(5):248-257
Here we present results of an initial assessment of the impacts of a water diversion event on the concentrations and chemical composition of dissolved organic matter (DOM) and bacterioplankton community composition in Barataria Bay, Louisiana U.S.A, an important estuary within the Mississippi River Delta complex. Concentrations and spectral properties of DOM, as reflected by UV/visible absorbance and fluorescence, were strikingly similar at 26 sites sampled along transects near two western and two eastern areas of Barataria Bay in July and September 2010. In September 2010, dissolved organic carbon (DOC) was significantly higher (568.1-1043 μM C, x=755.6+/-117.7 μM C, n=14) than in July 2010 (249.1-577.1 μM C, x=383.7+/-98.31 μM C, n=14); conversely, Abs254 was consistently higher at every site in July (0.105-0.314) than in September (0.080-0.221), averaging 0.24±0.06 in July and 0.15±0.04 in September. Fluorescence data via the fluorescence index (FI450/500) revealed that only 30% (8 of 26) of the July samples had an FI450/500 above 1.36, compared to 96% (25 of 26) for the September samples. This indicates a more terrestrial origin for the July DOM. Bacterioplankton from eastern sites differed in composition from bacterioplankon in western sites in July. These differences appeared to result from reduced salinities caused by the freshwater diversion. Bacterioplankton communities in September differed from those in July, but no spatial structure was observed. Thus, the trends in bacterioplankton and DOM were likely due to changes in water masses (e.g., input of Mississippi River water in July and a return to estuarine waters in September). Discharge of water from the Davis Pond Freshwater Diversion (DPFD) through Barataria Bay may have partially mitigated some adverse effects of the oil spill, inasmuch as DOM is concerned. 相似文献
16.
海州湾南部海域不同季节虾类数量及其分布特征 总被引：3，自引：0，他引：3
根据2009年5月、9月和12月对海州湾南部海域3个航次的渔业资源调查资料,对该海域十足目虾类的数量和分布的特征进行了初步研究,且探讨了优势种、温度、盐度、水深等因素对以上特征的影响。结果表明,5月虾类资源量最高,9月最低,12月较9月有所回升,分别以戴氏赤虾Metapenaeopsis dalei和日本鼓虾Alpheus japonicus、细巧仿对虾Parapenaeopsis tenella和刀额新对虾Metapenaeus ensis、日本鼓虾等为主要优势种。5月和9月虾类平面分布趋势均为西北外侧和东南水域较低,南面沿岸较均匀,东部和中部出现最高值;12月北面和南面近岸资源量较低,其他水域较均匀,最高值出现在东部水域。逐步回归分析表明,海州湾虾类资源量与底盐间存在显著相关关系,其他水文因素无显著相关关系。此外,优势种生态习性、赤潮和径流等是影响海州湾虾类数量和分布变化的主要因素。 相似文献
17.
V. M. Sergeeva I. N. Sukhanova E. I. Druzhkova S. A. Mosharov V. V. Kremenetskiy A. A. Poluhin 《Oceanology》2016,56(1):107-113
The phytoplankton community and its distribution were investigated in the eastern branch of the St. Anna Trough and over the adjacent Kara Sea shelf in September 2011 and in August 2014. The spatial and seasonal differences in the phytoplankton structure were analyzed in connection with ice melting and changes in the temperature, salinity, and biogenic regime. Four 4 zones were defined: the Kara Sea shelf, the upper part of the St. Anna Trough slope, the lower part of the St. Anna Trough slope, and its deep part. It was shown that over the Kara Sea shelf where riverine runoff influence was observed, the phytoplankton community differs from the community of the St. Anna Trough in both investigated periods: in September and August. Rearrangement of the phytoplankton community was observed in the frontal zone associated with the upper part of the slope in September of 2011. The main features of this rearrangement were a change in dominant species composition and a 1.5–2-fold increase in the number and biomass of algae. Over the lower part of the slope and deep area of the St. Anna Trough in August 2014 and September 2011, the phytoplankton community was at different successive stages: in August, at the late spring and summer stage, and in September, at the summer–autumn stage. 相似文献
18.
青岛近海夏季海风特征及其预报方法研究 总被引：3，自引：1，他引：2
采用2003～2006年7～9月青岛以及沿海地区自动站资料、探空资料对青岛近海海风进行了统计分析.平均而言,青岛近海7～8月海风发生频率为30%～35%,9月海风发生频率为25%;海风开始时间平均为10:00～12:00,结束时间可以持续到18:00～19:00;海风在垂直方向上厚度为500～600 m左右.青岛近海海风的发生与否取决于青岛上空低层925 hPa风速大小、低层大气稳定度、海陆温差以及海平面气压差四方面的综合效应.通常,925 hPa风速达到8 m/s,系统风较强时不利于海风建立;当低层大气不稳定时,有利于触发海风环流的建立;海陆温差达到4 ℃以上时,青岛近海易出现海风;此外,当地转风为离岸风时,海阳站或日照站与青岛本站08:00时海平面气压差>1 hPa时,当日一般不会出现海风.综合以上预报因子及其指标,通过建立逻辑回归模型,初步实现了夏季青岛近海海风能否发生的客观预报,并在2007年举行的国际帆船赛期间得到了应用. 相似文献
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20.
Keisuke Taira Mohd Nasir B. Saadon Shoji Kitagawa Tetsuo Yanagi 《Journal of Oceanography》1996,52(2):251-257
Mooring observation of current and temperature was made at 17.8 m layer of 19 m depth about 8 km east to Kuala Terengganu, Peninsular Malaysia. Harmonic analysis was applied to tidal currents for 30 days in September 1993, and to the tides observed at Chendering. The K1 tide was the largest both in tidal currents and the tides. Daily mean temperature, currents, sea level, and winds were analyzed from September 1993 to May 1994. Northeast Monsoon from December to February caused sea level rise of 50 cm and temperature lowering of 1°C. 相似文献