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1.
船舶的微生物腐蚀与防护技术*   总被引:2,自引:0,他引:2  
王毅  张盾 《海洋科学集刊》2016,51(51):58-68
海洋环境中的微生物腐蚀已被公认为是海洋工程金属构筑物的腐蚀破坏的重要形式。航行在海洋中的船舶不仅受到海水腐蚀的影响,各个部件还会受到微生物腐蚀的影响。严重的微生物腐蚀会导致管路阻塞、部件失效和腐蚀穿孔,不仅影响船舶设备正常运行,也严重威胁船舶安全。本文系统分析了船舶微生物腐蚀发生的位点和危害、不同位点的腐蚀微生物群落结构特征、船舶材料的微生物腐蚀以及不同防护技术的适用范围,并在此基础上提出对船舶微生物腐蚀研究工作的建议。  相似文献   

2.
海水中Ca2+,Mg2+, K+含量对黑鲷胚胎及早期仔鱼发育的影响   总被引:3,自引:0,他引:3  
1992 ̄1993年,用不同Ca^2+,Mg^2+和K+含量的人工配制海水,孵化黑鲷(Sparus macroephalus Basilewsky)受精卵,培育前期仔鱼。实验揭示了:在没有Ca^2+的海水中不能孵出仔鱼,在没有Mg^2+的海水中能孵出少量畸形仔鱼;低K^+对黑鲷受精卵孵化无明显影响,但对早期仔鱼的影响明显。针对咸淡水域海水鱼类育苗的特点,提出了调配海水中适宜的Mg^2+/Ca^2+  相似文献   

3.
钢在海水中的腐蚀产物相组成研究报道较少。马如璋等(1981,1982)对低合金钢在海水中的腐蚀锈层进行了研究,他们所采用的穆斯堡尔谱等方法,很适宜研究钢的腐蚀产物(Simmons,1976; Vertes,1989)。目前,由于石油工业的发展,大量的石油平台、栈桥及钢柱码头不断涌现,这些构造物的钢桩一般是从大气区经过飞溅区、潮差区和海水全浸区插入海泥区,大量研究表明,在海水、海泥跃变区钢铁腐蚀严重,作者采用穆斯堡尔谱对A3钢在室内模拟和实海锈层相的组成进行了初步的研究,以探讨在不同腐蚀环境中钢铁的腐蚀产物和腐蚀机理,为钢铁的防腐和耐海洋腐蚀钢的开发提供理论依据。  相似文献   

4.
DH36钢焊接件海水腐蚀行为研究   总被引:2,自引:0,他引:2  
海洋环境中的钢焊接件除了易发生电化学腐蚀之外,还容易发生电偶腐蚀等局部腐蚀。本文通过失重法、开路电位、强极化曲线、金相显微观测和X射线衍射等测试方法研究了DH36海洋用钢焊接件S-189-2在海水介质中的电化学腐蚀行为、电偶腐蚀倾向及其腐蚀产物成分。结果表明,焊接件各个部位在海水中的腐蚀速率均较小,腐蚀电流密度在15~29μA.cm-2范围内,阴极反应由氧扩散过程控制。开路电位和电极电位均随时间负移,各个位置电极电位差较小且负移幅度接近,发生电偶腐蚀的倾向较小。腐蚀产物以γ-FeO(OH)为主。  相似文献   

5.
杨嘉东 《海洋科学》1984,8(2):29-31
维生素B_(12)(C_(63)H_(90)CoN_(14)O_(14)P)又名钴胺素,是一种含钴的有机化合物。在动物的肝脏、肌肉、乳品、蛋黄和某些贝类中含量丰富。许多海洋生物能利用海水中的痕量钴来合成B_(12)。我国有关水产部门曾对毛蚶体内B_(12)的提取进行过研究,测得每克毛蚶鲜肉中含有B_(12)O.65—O.85微克。~(60)Co是海洋放射性  相似文献   

6.
Cu2+,Zn2+,Pb2+,Cd2+对刺参幼虫的毒性试验   总被引:4,自引:0,他引:4  
张晓燕 《海洋科学》1994,18(2):9-12
为摸清重金属Cu2+,Zn2+,Pb2+,Cd2+对刺参幼虫的影响程度,于1986~1988年在威海市西港渔业公司育苗场进行了其毒性试验。1材料与方法1.1试验方法采用生物毒性试验[1,2],根据试验持续时间和毒物浓度,分急性中毒试验和亚急性中毒试验。生物致毒的方法是接触致毒,即准确称量一定数量的CuSO4,ZnSO4,Pb(NO3)2,CdSO4,分别配制成一定浓度的母液,然后按试验组浓度要求将母液加入不同试验组的过滤海水中,试验生物在其内培养。试验所用的过滤海水采自威海市田村小石岛海区的自然…  相似文献   

7.
海水腐蚀不仅对海洋工程带来了严重的危害,同时会对海洋生态环境产生影响。在海洋工程决策和开发建设活动开始前,对海水腐蚀作出环境评价,并反馈给决策者和开发者,可以有效地调整和完善项目决策和开发活动,有助于海洋开发利用的可持续发展。文章根据多年来对环渤海海洋工程的海水腐蚀调查、海水腐蚀与海洋环境的研究,结合我国海水腐蚀在环境评价中的应用现状,论证了海水腐蚀作为海洋环境评价指标的重要性和必要性;提出了海水腐蚀在海洋环境评价中的操作步骤。  相似文献   

8.
由于海水对金属的腐蚀性,对海水输水管道及各种海水冷却器的使用造成严重威胁,极需研制一种成本低、生产工艺简单而又耐海水腐蚀的低合金钢。达方面研究国外已有报道。他们研制的低合金钢是以铬为主添加合金元素的铬-铝和铬-钼型钢,含铬量约在2%以上。这类钢在海水中耐蚀性一般为碳钢  相似文献   

9.
船舶Cu-Ni合金海水管系的微生物腐蚀与控制   总被引:3,自引:0,他引:3  
刘光洲 《海洋科学》2005,29(7):87-90
Cu-Ni合金由于具有良好的耐海水腐蚀性能、机加工性能以及良好的导电导热性能,而被广泛用于船舶的海水管系如冷凝器、海水管路、热交换器等。然而,事实证明,Cu及其合金在短期的实验室试验中表现出良好的耐蚀性能,而在长期的使用中往往表现出早期失效现象。研究表明,微生物在铜镍合金的腐蚀过程中起了主导作用,铜镍合金虽然不发生海生物污损,却具有微生物腐蚀的敏感性。  相似文献   

10.
含有大比例CO_2和H_2S的天然气均称为酸性气体。由于酸气的腐蚀作用和天然气开采、输送、加工系统往往是在相当高的压力下进行的,任何腐蚀穿孔或破裂都会使压力突然释放。导致严重的爆炸和燃烧,对人和有关设备会构成极大的危害。  相似文献   

11.
制盐工业的发展趋向于大型化、自动化。新工艺、新技术、新设备的不断出现与利用,加上原卤多样化,设备材料所处的腐蚀介质更加苛刻,因此金属材料的腐蚀问题更加严重,迫切需要解决相应的耐蚀材料。E_2钢的研制已  相似文献   

12.
The ‘International Intercomparison Exercise of fCO2 Systems’ was carried out in 1996 during the R/V Meteor Cruise 36/1 from Bermuda/UK to Gran Canaria/Spain. Nine groups from six countries (Australia, Denmark, France, Germany, Japan, USA) participated in this exercise, bringing together 15 participants with seven underway fugacity of carbon dioxide (fCO2) systems, one discrete fCO2 system, and two underway pH systems, as well as systems for discrete measurement of total alkalinity and total dissolved inorganic carbon. Here, we compare surface seawater fCO2 measured synchronously by all participating instruments. A common infrastructure (seawater and calibration gas supply), different quality checks (performance of calibration procedures for CO2, temperature measurements) and a common procedure for calculation of final fCO2 were provided to reduce the largest possible amount of controllable sources of error. The results show that under such conditions underway measurements of the fCO2 in surface seawater and overlying air can be made to a high degree of agreement (±1 μatm) with a variety of possible equilibrator and system designs. Also, discrete fCO2 measurements can be made in good agreement (±3 μatm) with underway fCO2 data sets. However, even well-designed systems, which are operated without any obvious sign of malfunction, can show significant differences of the order of 10 μatm. Based on our results, no “best choice” for the type of the equilibrator nor specifics on its dimensions and flow rates of seawater and air can be made in regard to the achievable accuracy of the fCO2 system. Measurements of equilibrator temperature do not seem to be made with the required accuracy resulting in significant errors in fCO2 results. Calculation of fCO2 from high-quality total dissolved inorganic carbon (CT) and total alkalinity (AT) measurements does not yield results comparable in accuracy and precision to fCO2 measurements.  相似文献   

13.
采用线性极化电阻法,测试了C60全珊瑚海水混凝土(coral aggregate seawater concrete,简称CASC)的线性极化曲线、自腐蚀电位(Ecorr)和极化电阻(Rp),研究了不同暴露时间、不同种类钢筋CASC的钢筋腐蚀行为,提出了提升岛礁CASC结构耐久性的建议措施。结果表明:随着暴露时间的延长,CASC的EcorrRp均逐渐降低,钢筋的耐蚀性能逐渐减弱。不同种类钢筋CASC耐蚀性能规律为:316不锈钢筋优于有机新涂层钢筋,优于普通钢筋。即使暴露0 d,CASC中普通钢筋仍会发生锈蚀,表明普通钢筋在不附加任何防腐措施的条件下不适用于岛礁CASC结构。综合分析阻锈效果和成本因素,316不锈钢筋的性价比明显低于有机新涂层钢筋,建议岛礁CASC工程优先选用有机新涂层钢筋。  相似文献   

14.
朱杰  张辉  张鹏翔  谢康  胡俊涛 《海洋学报》2010,32(9):6417-6422
采用脉冲激光沉积(PLD)技术在LaSrAlTaO3(LSATO),LaAlO3(LAO)和SrTiO3(STO)的单晶倾斜衬底上成功制备了Pb(Zr0.3Ti0.7)O3(PZT)薄膜,在三种倾斜衬底上生长的PZT薄膜中都首次发现了LIV效应.对PZT/LSATO薄膜在a,c轴两种不同取向择优生长下的LIV效应做了研究,发现在薄膜c轴取向择优生长  相似文献   

15.
张帆  朱航天  骆军  梁敬魁  饶光辉  刘泉林 《海洋学报》2010,32(10):7232-7238
以室温热电性能优异的传统热电材料Sb2Te3为研究对象,利用化学气相沉积法制备Sb2Te3单晶纳米结构,并研究其生长机理.实验结果表明,不加催化剂时Sb2Te3易生长成六方纳米盘,在金催化剂条件下定向生长成纳米线.Sb2Te3的形貌与其晶体结构和生长机理有关.Sb2Te3为三角结构,Sb和  相似文献   

16.
Ideally, the correction of the measured CO2 fugacity (fCO2) at temperature Tm to fCO2 at the in-situ temperature Tin should be made by using at least 2 known parameters (pH-AT, CT-AT,…) and the reliable constants for carbonic acid. In practice however, a measured CO2 property pair is not always available. When fCO2 is measured alone, one must make an estimate of the effect of temperature on seawater fCO2 from the accurate knowledge of seawater salinity and temperature and the approximate knowledge of the carbonate parameters. In this paper we present an empirical relationship that can be used to estimate the effect of temperature on fCO2. The equation is of the form:
ƒCO2[t] − ƒCO2[20]=A + Bt + Ct2 + Dt3 + Et4
where fCO2[t] and fCO2[20] represent fCO2 at temperatures t°C and 20°C, respectively; the parameters A, B, etc. are functions of the ratio X = CT/AT:
E = e0 + e1X + e2X2ln(X) + e3exp(X) + e4/ln(X)
where the parameters ai, bi, etc. are functions of salinity.The 25-parameter equation is fitted by the values of fCO2 calculated using the constants of Goyet and Poisson (1989), when X varies from 0.8 to 1.0, t varies from −1dgC to 40°C, and S varies from 30 to 40. For Tm - Tin within ± 10°C, direct measurements of fCO2 as a function of the temperature (from −I to 30°C verify this equation within less than ±5 μatm.  相似文献   

17.
于1989-1991年对深圳湾、大鹏湾海水及底记的维生素B1和B12含量进行了测定。结果表明,两湾海水中维生素B1和B12含量绝大多数在10ng/L以下;在底泥中的含量最高也仅36×10-9,不会诱导赤潮发生。  相似文献   

18.
In the Mediterranean Sea the carbon chemistry is poorly known. However, the impact of the regional and large-scale anthropogenic pressures on this fragile environment rapidly modifies the distribution of the carbonate system key properties like CT (total dissolved inorganic carbon), AT (total alkalinity), CANT (anthropogenic CO2), and pH. This leads inexorably to the acidification of its waters. In order to improve our knowledge, we first develop interpolation procedures to estimate CT and AT from oxygen, salinity, and temperature data using all available data from the EU/MEDAR/MEDATLAS II database. The acceptable levels of precision obtained for these estimates (6.11 ??mol-kg−1 for CT and 6.08 ??mol kg−1 for AT) allow us to draw the distribution of CANT (with an uncertainty of 6.75 ??mol kg−1) using the Tracer combining Oxygen, inorganic Carbon, and total Alkalinity (TrOCA) approach. The results indicate that: 1) all Mediterranean water bodies are contaminated by anthropogenic carbon; 2) the lowest concentration of CANT is 37.5 ??mol kg−1; and 3) the western basin is more contaminated than the Eastern basin. After reconstructing the distribution of key properties (CT, AT, CANT) for four periods of time (between 1986 and 2001) along a west-east section throughout the whole Mediterranean Sea, we analyze the impact of the Eastern Mediterranean Transient (EMT). Not only has the concentration of CANT increased (especially in the intermediate and the bottom layers of the eastern basin, during and after the EMT), but also the distribution of all properties has been considerably perturbed. This is discussed in detail. For the first time, the level of acidification is estimated for the Mediterranean Sea. Our results indicate that for the year 2001 all waters (even the deepest) have been acidified by values ranging from −0.14 to −0.05 pH unit since the beginning of the industrial era, which is clearly higher than elsewhere in the open ocean. Given that the pH of seawater may affect a very large number of chemical and biological processes, our results stress the necessity to develop new programs of research to understand and then predict the evolution of the carbonate system properties in the Mediterranean Sea.  相似文献   

19.
生物固氮作用是一个重要的海洋新氮来源,在海洋生物地球化学循环中扮演着不可替代的角色。基于稳定同位素(15N2)示踪吸收法,是目前直接测定海洋生物固氮速率最有效的手段。其中,高效、洁净地将15N2引入海水培养体系,并准确定量培养体系底物的同位素示踪水平,是同位素示踪吸收法准确获取固氮速率的关键。本研究针对15N2同位素示踪剂引入这一关键环节进行了探讨,确认改进气泡法是将15N2引入海水培养体系的首选操作。在对培养体系造成的较小扰动的情况下,可将培养体系氮气底物的15N原子丰度提升至10%以上,相对于另一种导入同位素示踪剂的手段——预溶解海水法,改进气泡法将培养瓶中氮气底物的15N原子丰度提升了近200%。此外,改进气泡法还具有最小化痕量金属沾污、操作简便等优点。将改进气泡法结合与稳定同位素比值质谱测定结合,是准确测定水体生物固氮速率的推荐方法。  相似文献   

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