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1.
EFFECT OF SULPHATE-REDUCING BACTERIA ON ELECTRO-CHEMICAL CORROSION BEHAVIOR OF 16Mn STEEL IN SEA MUD
ＩＮＴＲＯＤＵＣＴＩＯＮＩｔｗａｓｇｅｎｅｒａｌｌｙｃｏｎｓｉｄｅｒｅｄｐｒｅｖｉｏｕｓｌｙｔｈａｔｔｈｅｃｏｒｒｏｓｉｏｎｏｆｓｔｅｅｌｉｎｓｅａｍｕｄｗａｓｎｏｔｓｅｒｉｏｕｓ.Ｈｏｗｅｖｅｒ,ｉｔｗａｓｌａｔｅｒｆｏｕｎｄｔｈａｔｔｈｅｃｏｒｒｏｓｉｏｎｒａｔｅｏｆｓｔｅｅｌｉｎｓｏｍｅｓｅａｍｕｄｗａｓｈｉｇｈｅｒｔｈａｎｔｈａｔｉｎｓｅａｗａｔｅｒ(Ｋｉｎｇ,1980;Ｓｅｈｍｉｄｅ,1982;Ｇｕｏｅｔａｌ.,1997;Ｈｏｕ,1998).Ｔｈｅｒｅａｒｅｓｏｍｅｒｅｐｏｒｔｓｔｈａｔｔｈｅｃｏｒｒｏｓｉｏｎｒ… 相似文献
2.
《中国海洋湖沼学报》2017,(5)
Defects in protective-coating systems on steel surfaces are inevitable in practical engineering applications.A composite coating system,including a primer,middle coat and topcoat,were used to protect carbon steel from corrosion in a marine environment.Two environmental additives,glass fi bers and thiourea,were applied in the middle coat to modify the coating system.The long-term corrosion durability and self-healing ability of the scratched coating system were evaluated by multiple methods.Results of the electrochemical technologies indicated that the coating system that contained 0.5 wt.%fi bers and 0.5 wt.%thiourea presented good corrosion protection and self-healing for carbon steel when immersed in 3.5%Na Cl for 120 d.Evolution of localized corrosion factors with time,as obtained from the current distribution showed that fi bers combined with thiourea could inhibit the occurrence of local corrosion in scratched coating systems and retarded the corrosion development signifi cantly.Surface characterization suggested that adequate thiourea could be absorbed uniformly on fi bers for a long time to play an important role in protecting the carbon steel.Finally,schematic models were established to demonstrate the action of fi bers and thiourea on the exposed surface of the carbon steel and the scratched coating system in the entire deterioration process. 相似文献
3.
王佳 《中国海洋湖沼学报》1997,15(4):369-372
ImooUcr0NCormsinnofsodinconatisnowrognindasaseriousproblemwithlargeere-nondconSequenas.Thecormsionproducofondatthesurfaeeofrenfontin-dutaltenSioninthernaterial,resultinginfraCtureandspillingoftheconcretefromtherenfoot(Madrinaldetal.,l99l).Asaasult,theconCretestructure'sIneCanhalstwthisgreatiytalued.0wingtothephyShaldfultyofconduCtingforchdricalexperiInentsinconare,muCoftheworkintheaasofndanisticdCtendnationsforcormsionofstalincon-~wereconduedinalkalinesolution,generallyofporewatCr(Romirz… 相似文献
4.
Study on rust layers on steel in different marine corrosion zone 总被引：1，自引：0，他引：1
IrmODUCnONTheMossbaureffect(ME)isalsoknOWnasrecoil-thenuclearresonaneabsorp-hon.MossbaursPeCboscoPy(MS)haspIDvedtobeaveryuSefultecheqUeforstudytngcormsionPimessesandcedon-cts.TheInainadvantagsofMSincormsionre-enhare:(l)thenon-deStrutivechateroftheteCboqUe;(2)possibilltyforquali-tativeandqUanitativephaanalsis;(3)uSehassinidenificationofPOOrlycrystal-lizedoramorphouscormsionpnhats.WththedeVfoPmntofInarineresomees,InansteelconstrUctionswerebulltatsea'MSwasusedforanalfongcormsion~t… 相似文献
5.
INTRODUCTIONBesidesprotectivecoatingandcathodicprotectionmethodsagainstcorrosionoflowalloysteelconstructuresinmarineenvironment,itisalsoimportanttoimprovethecorrosionresistanceofthelowalloysteelitself.Therearefewreportsontherelationshipofalloyelementandthecorrosionre sistanceofsteel .Larrabee (1 958)’s 5-9yearsseaexperimentusinglong scalesteelshowedthatthecorrosionresistanceof 0 .5%Ni-0 .5%Cu -0 .1 %Psteelwasthehighestinthesplashzone .HouandZhang (1 980 )consideredthataproperrelationshi… 相似文献
6.
设计一种新型光纤光栅锈蚀传感器,主要由锈蚀体、不锈钢体和2段串联的光纤布拉格光栅（FBG）组成。缠绕于锈蚀体表面的FBG监测钢筋的锈胀应变,缠绕于不锈钢体表面的FBG用作温度补偿器,消除温度变化对锈胀应变监测的影响。此外,设计电化学加速腐蚀实验,探究该传感器在不同强度等级混凝土中的工作性能。结果表明,该传感器监测质量腐蚀率的灵敏度为0.02%,监测范围大于1%,可实时监测混凝土中钢筋的锈蚀过程及特征,为预警钢筋锈蚀引起的钢筋混凝土结构耐久性损失提供阈值,在结构健康监测领域具有较大的应用价值。 相似文献
7.
hacteria(SRB)canbeashighastenhmesthainseahattOInsetlimentwithouSRB.Theex-perimentsinsimulatingseahattmsedimentswithdifferentconcenhations0fcultUredSRBsh0WedthatheelecthehendcalpoariZaionbehavi0ur0fsteelinseahatt()msedimentwithandwithouSRBwerefferent.SRBalteredthepoarizationbehavi0ur0fsteelsignificanilbyaciopingtheenvironments0thaaP-parenthydrogendepoallzationoccurredandacceleratedthec0meionofsteel.Keywofor:anaerohe,seab0ttomsediment,steelINTRODUCTIONAnaerobesaregenerallypresentins… 相似文献
8.
北部湾江洪扇贝养殖区的污损生物 总被引：1，自引：0，他引：1
2006年8月至2007年7月,对北部湾江洪扇贝养殖区的污损生物进行周年调查。结果表明:该海区养殖网笼的污损生物有8门20种,优势种为藤壶、钩虾、苔藓虫,其次是翡翠贻贝、牡蛎、海鞘、大型藻类和水螅。污损生物附着高峰在8、11和12月,1月的附着数量最少;藤壶附着高峰在8、11和12月,附着生物量占污损生物总量的56.0%,是养殖区污损生物防除的重点对象;钩虾附着高峰出现在8、9月,12和2月附着量也较高,其生物量占污损生物总量的18.0%;草苔虫附着高峰出现在4月,其生物量占污损生物总量的8.4%。污损生物附着量呈现由表层向底层递减的趋势。 相似文献
9.
The Al-basic sacrificial anode is widely used to protect steel construction from corrosion in seawater,but is not suitable for protecting steel in freshwater. In the estuary area, seawater and freshwater mix anddifferent seawater salinity can be formed in different mixing sites between freshwater and seawater. Basedon the requirements of the Shengli Petroleum Administrative Bureau of China, the effect of seawatersalinity on electrochemical properties of Al-basic anode was studied under laboratory conditions by themethod given in National Standard GB 4948-85 (China Starndard Bureau, 1985). No obvious effectwas found when seawater salinity was 30 to 10, but obvious effect on anodic open circuit potential, closedcircuit potential and current efficiency was found when seawater salinity was 5. These values are lowerthan those given in the Naional Standard. 相似文献
10.
ＩＮＴＲＯＤＵＣＴＩＯＮＢｉｏｆｏｕｌｉｎｇｃａｎｃａｕｓｅｒｏｕｇｈｎｅｓｓｏｆｓｕｂｍｅｒｇｅｄｓｕｒｆａｃｅｓｏｆｍａｒｉｎｅｓｔｒｕｃｔｕｒｅｓ(Ｃｈａｋｒａｂａｒｔｉ,1991),ｉｎｃｒｅａｓｅｈｙｄｒｏｄｙｎａｍｉｃｌｏａｄｉｎｇｓ(ＷｏｌｆｒａｍａｎｄＴｈｅｏｐｈａｎａｔｏｓ,1985),ａｃｃｅｌｅｒａｔｅｃｏｒｒｏｓｉｏｎｐｒｏｃｅｓｓ(Ｐａｔｉｌｅｔａｌ.,1988),ａｎｄｉｍｐｅｄｅｕｎｄｅｒｗａｔｅｒｉｎｓｐｅｃｔｉｏｎａｎｄｍａｉｎｔｅｎａｎｃｅ(Ｈｏｕｇｈｔｏｎ,1978).Ｔｈｅｌａｃｋｏｆｄ… 相似文献
11.
研究了4种Hg2+浓度对细基江蓠果孢子和四分孢子附着、萌发和生长的影响。结果表明:与对照组相比,Hg2+抑制了果孢子附着却促进了四分孢子的附着,但0.0025 mg/L浓度与对照组的差异不显著(P>0.05),各浓度间差异显著(P<0.05);Hg2+在实验浓度范围内(0.0025、0.0050、0.0075、0.0100 mg/L)影响了孢子的正常萌发,使孢子不能正常分裂和生长,刺激了孢子脱落,并且使盘状体的形态发生变异;`Hg2+不同浓度之间也存在显著差异(P<0.05),并且Hg2+浓度越高对孢子的萌发和生长影响越大。 相似文献
12.
为了研究不同腐蚀条件下的焊缝磁记忆特征信号,对20号钢板状焊缝试件进行残余应力腐蚀、35kN恒拉伸应力腐蚀和35kN静载、25kN动载拉拉腐蚀疲劳对比实验,分析焊缝正、反面磁记忆信号的变化规律,获得焊缝腐蚀发展进程中应力腐蚀与腐蚀疲劳各自对应的磁记忆特征信号.结果表明:在应力腐蚀状态下,不同拉伸载荷对应的磁记忆信号特征不同,35kN恒拉伸应力腐蚀与残余应力腐蚀相比,焊缝区磁记忆信号峰峰值及其梯度更大,磁记忆曲线分布的分散度更大;35kN静载、25kN动载拉拉腐蚀疲劳与35kN恒拉伸应力腐蚀相比,焊缝区磁记忆曲线上下波动多,过零点次数多,磁记忆曲线分布的分散度小.这为磁记忆技术在焊缝工程检测的定性与定量分析提供基础数据. 相似文献
13.
《中国海洋湖沼学报》2020,(2)
Copper has long been utilized as a disinfectant for bacteria,but its impact on microbial communities attached to the steel surface in seawater remains unknown.In the present study,3 mooring chain steels of different copper contents are subjected to a 3-month marine field exposure,and the corrosion rate increases in the order of BR5 steel(without copper) BR5 CuH steel(0.8% copper) BR5 CuL steel(0.4% copper).The microbial community results show that copper introduction does not result in an obvious change in microbial quantity,but it alters the diversity,richness,and structure of microbial communities due to the variation in copper-resistance of different species.BR5 CuH steel holds microbial communities with the highest percentage of some well-known corrosive microbes including sulfate-reducing bacteria,sulfuroxidizing bacteria,and iron-oxidizing bacteria,but possesses the lowest community diversity/richness owing to the toxicity of copper.The microbial community diversity/richness is stimulated by the low-copper content of BR5 CuL steel,and this steel also carries an intermediate proportion of such corrosive bacteria.Both well-known corrosive bacteria and microbial community diversity/richness seem to be involved in the corrosion acceleration of copper-bearing mooring chain steels. 相似文献
14.
As a material with good corrosion resistance,5083 aluminum alloy has a great application prospect in marine environment.In this work,the corrosion characteristics of 5083 aluminum alloy in seawater containing phosphate were investigated with Potentiodynamic Polarization,Electrochemical Impedance Spectroscopy (EIS),Scanning Electron Microscope (SEM),Energy Dispersive Spectroscopy Analysis (EDSA),X-ray Photoelectron Spectroscopy (XPS) and Laser Confocal Microscope.The results indicated that the effects of phosphate in seawater were two-fold.Firstly,phosphate slightly accelerated the corrosion of 5083 in seawater in the early stage of corrosion.HPO_4~(2-)competed with OH~-in the adsorption process on the alloy surface,which weakened the contact between OH~-and Al~(3+)near the interface of the alloy,and inhibited the formation as well as the self-repair of the passive film,thus accelerating the activation dissolution process.Compared with the natural seawater,the charge transfer resistance of 5083 in the seawater containing phosphate decreased faster during the early stage of corrosion,and the corrosion current density icorr was higher in seawater containing phosphate.On the other hand,the addition of phosphate would not affect the cluster distribution of the second phase of 5083 in seawater,but it changed the composition of the corrosion product layer and had an obvious inhibitory effect on the local corrosion of 5083 in seawater.After 16-day exposure,shallower and more sparsely distributed pits could be observed on the derusted surface of 5083 in the seawater containing phosphate,and the pitting coefficient in the seawater containing phosphate was significantly lower than that in natural seawater.The reduction of pitting tendency could be realized mainly through two ways.First,the HPO_4~(2-)adsorbed on the surface of the passive film in the early stage of corrosion and repeled the corrosive anions such as Cl~-.Second,phosphate participated in the construction of the Ca HPO_4 precipitation film,which acted as a barrier and protection. 相似文献
15.
《中国海洋大学学报(英文版)》2015,(2)
The current distributions over carbon steel under iron red alkyd primer exposed to 3.5% sodium chloride solution were mapped using the wire beam electrode(WBE). The electrochemical impedance spectroscopy(EIS) of the WBE was carried out to analyze the performance of coating delamination and corrosion behavior of carbon steel beneath defective coating. The EIS data revealed that protective capability of coating decreased with immersion time and the degree of cathodic delamination showed a rapid rise. The current density distribution of WBE indicated that cathodic sites was located at the defect at the beginning of immersion and gradually spread into the intact coating. The cathodic regions were distinguished from the anodic area and distributed over the WBE. The changes of cathodic sites could reflect the deterioration process of defective coating. The cathodic area ratio was a more useful parameter than the cathodic delamination degree to evaluate the coating cathodic delamination. The polarity reversals of electrodes at the defect and beneath coating were observed. A simple discussion of relationship between the blister and the polarity reversal was made from a standpoint of electrochemical distribution. WBE method was able to map and record the changes of local cathodic sites beneath defective coating in real time, which could provide more detailed information about the local degradation of coating. 相似文献
16.
The Al—basic sacrificial anode is widely used to protect steel construction from corrosion in seawater, but is not suitable
for protecting steel in freshwater. In the estuary area, seawater and freshwater mix and different seawater salinity can be
formed in different mixing sites between freshwater and seawater. Based on the requirements of the Shengli Petroleum Administrative
Bureau of China, the effect of seawater salinity on electrochemical properties of Al—basic anode was studied under laboratory
conditions by the method given in National Standard GB 4948-85 (China Starndard Bureau, 1985). No obvious effect was found
when seawater salinity was 30 to 10, but obvious effect on anodic open circuit potential, closed circuit potential and current
efficiency was found when seawater salinity was 5. These values are lower than those given in the National Standard.
Contribution No. 2681 from the Institute of Oceanology, Chinese Academy of Sciences. This study is a major project (Ky85-11-5)
and a key project (A14920416) of the Chinese Academy of Sciences, and also received support from the Shengli Oil Field. 相似文献
17.
ImooUonONSCCisoneofthemosttwortantcausoffailureofstaiuleSsstalequipmentandfacilitieS.Studiesonunh0refacilitiesshowedthatanaddicchloridesolutionfilmcouldbefo~onthescheeofstalandthatstaiuleSSstalisinaCtivedissolutionstateinaedicchloridesolutionopinetal.,l99O;Gnanamoorthyetal.,l99O).ltisgenerallythoughtxthatSCCcannotoimrwhenthematerialisinaCtiveanodicdissolutionstate,soitsomcewithresultingcasualties(0ldfieldetal.,l99O)arousedattentiont0it.SomeSCCmeCanisrnsproposedpeuang,l988,Newmanctal.,… 相似文献
18.
由于地域、天气等原因造成的云影问题,导致了水体时序分析困难。本文以资源三号（ZY-3）影像作为辅助数据,以环境与灾害监测预报小卫星影像（HJ-1）作为研究数据,通过提取一个时间段内多景时相相近HJ-1数据中有效水体信息,迭代补充成完整的水体提取结果,将不同时间段内影像水体提取的完整结果形成时序监测数据,以达到对某地区水体时序变化监测的目的。通过对淮河流域安徽段研究区水体分布监测表明,该方法能充分利用每个时间段内质量不理想的源数据,对相近时相数据迭代补充,完整提取该时间段内的水体信息。多个时间段迭代补充形成的时序数据可有效支持时序监测。本文在研究区共选取了8295个查找点,结果表明：2013年该研究区洪季（7、8月）水体信息比旱季（3、4月）更丰富,特别是东南部在洪季形成了许多零散水体;相较于旱季,洪季研究区水域面积增长了22.1%。 相似文献
19.
Y. M. Jo J. M. Oh J.G. Yoo 《中国海洋大学学报(英文版)》2006,5(4):305-310
The present paper deals with the behavior of the Attached Microbial Community （AMC） for water self-purification at different riverbeds in a typical local river. The study quantitatively investigated the problem starting with in-situ sampling. It was found that more biomass of AMC was at riffles with wider distribution than in pools. High current velocity （HCV） plays a negative role at the initial stage of attachment on the riverbed, but HCV aids the community proliferation after stable attachment. External disturbances such as rainfalls and discharges from dams or reservoirs would detach the periphyton depending on the intensity of turbulence in water. However, it was discovered that the flock of periphyton could be restored very quickly because it was not completely removed. Thus, in order to enhance self-purification by periphyton, a suitable configuration of the riverbed must be constructed, and occasional appropriate repair along the channels would improve the decontamination of the river. 相似文献
20.
Impact of the Wenchuan Earthquake on tourism in Sichuan, China 总被引：1，自引：1，他引：0
An intensive earthquake, the Wenchuan Earthquake of 8.0 on the Richter scale, struck western Sichuan, China on May 12, 2008. The earthquake has tremendously affected all industries in the quake-hit areas, with no exception ：of the local tourism. The study of the effect of the earthquake on tourism enriches the theory of tourism, and more importantly, it well serves as the foundation for policy making. The objective of this study is to outline for readers the empirical findings on the various ways that the earthquake affected the operations and viability of tourism in the quake-hit areas. This paper is mainly divided into 3 parts. The first part is to discuss the importance of tourism in the quake-hit areas. The second is to analyze the influencing factors of tourism. The third is to assess the impact of the earthquake on tourism in Sichuan in different seasons. 相似文献