共查询到20条相似文献，搜索用时 62 毫秒
1.
《武汉工程职业技术学院学报》2015,(3)
通过大气暴露试验和带锈样的电化学测试分析,对武钢生产的WNQ570钢在武钢工业大气下的耐腐蚀性能进行研究,8年的大气暴露腐蚀数据表明,WNQ570钢与09CuPCrNi钢相近,优于Q345钢,WNQ570钢的腐蚀率是Q345钢69%,是一种优良的耐工业大气腐蚀用钢。带锈样的测试结果表明,WNQ570钢锈层保护性能优于Q345钢。 相似文献
2.
对武钢生产的SPA-H和09CuPTiRE耐候钢在青岛、琼海和江津3个大气暴露试验点,暴露5年的腐蚀数据进行了分析。结果表明,SPA-H和09CuPTiRE钢的耐蚀性在各试验站均优于Q345钢,是一种优良的耐大气腐蚀用钢。大气暴露5年带锈样的极化曲线测试结果表明,耐候钢的锈层致密,防护性能就好。 相似文献
3.
Q345钢室内加速腐蚀与大气暴露的相关性研究 总被引：1，自引：0，他引：1
通过实验室的周浸腐蚀试验和自然环境的大气暴露试验,结合腐蚀产物的表面分析,研究了Q345钢在室内模拟大气腐蚀环境中的腐蚀规律和在青岛、江津、琼海的大气腐蚀规律,结果表明:在室内模拟加速腐蚀试验和大气暴露试验中,腐蚀规律均符合公式logP=A+Blogt,腐蚀产物一致,主要是α-FeOOH和γ-FeOOH,室内加速试验结果与户外暴露结果有较好的相关性。 相似文献
4.
综述了Q235钢在大气、土壤、溶液中的腐蚀与防护措施研究概况及存在的问题,以期为Q235钢的应用提供理论依据。 相似文献
5.
开展武钢生产的X65管线钢在琼海、江津、青岛5年大气暴露腐蚀试验,得到了X65管线钢在三地的大气腐蚀速率的数据,实验结果表明试验钢在琼海站耐蚀性最好,江津站次之,青岛站最差。分析环境因素得出影响材料耐腐蚀性能的关键因素是SO2沉积率、H2S含量和SO2-4含量。通过数据回归拟合,得出X65管线钢在三个实验站的腐蚀规律均符合公式D=A·tn。 相似文献
6.
利用极化曲线技术、电化学阻抗测试技术研究了X70钢在淡水中的腐蚀行为.实验结果表明,水温和流速对X70钢腐蚀的影响显著.随着温度的增加,X70钢的腐蚀速率也增加,X70钢在40℃的河水中腐蚀速度约为25℃时的3倍.用磁力搅拌器,人为造成水的流动状态,实验结果发现,X70钢在流动河水中的腐蚀速率大于静止河水,而且随着水的流速度的增加,X70钢的腐蚀速度增加. 相似文献
7.
通过周期性浸润腐蚀试验对贝氏体钢和对比钢09CuPCrNi进行了耐腐蚀性能的测定。结果表明,贝氏体钢的耐腐蚀性能与09CuPCrNi几乎相同。运用扫描电镜﹑透射电镜和X射线衍射仪等分析测试手段对两种钢的组织结构和锈层进行了观察和分析,对耐蚀机理进行了研究。贝氏体钢的板条贝氏体组织比传统耐候钢组织铁素体+珠光体组织更均匀,更耐腐蚀。锈层研究表明,贝氏体钢和09CuPCrNi钢的锈层主要的成分均是Fe3O4;两种钢的锈层均存在较多裂纹和缝隙,但还是存在一层致密且与钢基结合紧密的锈层。影响两种钢耐蚀性的主要因素是环境因素和化学成分,而组织结构只有在前两者基本相同的情况下,才起主要作用。 相似文献
8.
以柳屯原油库为例,采用慢应变拉伸法研究原油油罐罐底钢材(10#钢)的应力腐蚀特性,讨论拉伸速率和阴极极化对腐蚀速率的影响.结果表明,在试验条件下10#钢具有应力腐蚀开裂敏感性,其裂纹是氢致开裂引起的穿晶型应力腐蚀开裂;在阴极极化条件下,该材料——介质体系在自腐蚀电压电位下断裂寿命最长,其应力腐蚀敏感性最小、抗拉强度最大、应变量也最大.因此,对油罐罐底进行阴极保护防腐时,罐底钢材的自腐蚀电位为最佳保护电位值. 相似文献
9.
纯镁及AZ61镁合金在磷酸盐中形成转化膜后,分别在水、碱溶液及钒盐溶液中进行封闭处理.采用点滴腐蚀试验、孔隙率测试和模拟海水浸泡法对封闭后的膜层的耐腐蚀性能进行研究,用显微镜对腐蚀前后的微观形貌进行了观察,讨论了腐蚀机理.试验表明,在水中封闭的膜层的耐蚀性最好,膜层的孔隙率最低;纯镁的表面转化膜层的耐海水腐蚀性能比镁合金AZ61的表面转化膜层耐海水腐蚀性能好. 相似文献
10.
研究了温度、NaCl浓度以及溶液的pH值等环境因素对WDH36NF油船货油舱内底板用钢腐蚀速率、腐蚀形貌的影响。结果表明:油船货油舱内底板用钢的腐蚀速率随温度升高而增加。NaCl浓度由5%增大到10%,内底板用钢的腐蚀速率随浓度增大而增加,NaCl浓度由10%增大到15%,内底板用钢的腐蚀速率减小。pH值由0.5增大到0.85,内底板用钢的腐蚀速率随pH值增大而增加,pH值由0.85增大到1.2,内底板用钢的腐蚀速率减小,并趋于平缓。 相似文献
11.
罗艳萍 《读与写:教育教学刊》2008,5(6)
The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity. 相似文献
12.
Richard Denner 《海外英语》2007,(4):14-15
Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose. 相似文献
13.
Given a graph G,a subgraph C is called a clique of G if C is a complete subgraph of G maximal under inclusion and |C|≥2. A clique-transversal set S of G is a set of vertices of G such that S meets all cliques of G. The clique-transversal number, denoted as TC (G), is the minimum cardinality of a clique-transversal set in G. The clique-graph of G, denoted as K (G), is the graph obtained by taking the cliques of G as vertices, and two vertices are adjacent if and only if the corresponding cliques in G have nonempty intersection. Let F be a class of graphs G such that F={G|K(G) is a tree}. In this paper the graphs in F having independent clique-transversal sets are shown and thus TC (G)/|G|≤1/2 for all G ∈ F. 相似文献
14.
邱崇丙 《唐山师范学院学报》2014,(1):21-23
汉字的六书,《说文》对“转注”一类,语焉不详。后世学者提及转注,也仅限于许慎所举出的例字。《汉字例说》一文,作者从转注的角度综合考虑,对部分现代常用字作了分析,跟传统的解释有所不同。希望能抛砖引玉,互相切磋,以推进学术研究。 相似文献
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16.
陈美曦 《山东教育学院学报》2008,23(2):103-107
Different nations have different social cultures, and the social culture of every nation is developing with the development of the nation, language is greatly influenced by social culture, which enables language to possess national and historical characteristics. Word is the smallest, independent, meaningful linguistic unit of language. It can well reflect the national and historical characteristics. From synchronic aspect, the social and cultural influence on word meaning is mainly embodied in conceptual and associative meanings of word. The incorrespondence of word meaning is a phenomenon that exists in both conceptual and associative meanings of word among different languages. From diachronic aspect, the development of social culture causes some changes of word meaning to some extent. Therefore, social culture plays a key role in vocabulary learning and mastery of a language. 相似文献
17.
Rachel Zupek 《海外英语》2007,(11):40-41
我们绝大部分人都同意一件事情——我们喜欢金钱。但是你对金钱的喜欢之情足够到让你创立一份事业么?.财富通常被人忽视,主要在于人们不能真正了 相似文献
18.
《海外英语》2007,(4):36
There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love. 相似文献
19.
YANGShiguo 《重庆大学学报(英文版)》2004,3(1):86-88
The problem on the geometrc inequalities involving an n-dimensional simplex and its inscribed simplex is studied. Aninequality is established, which reveals that the difference between the squared circumradius of the n-dimensional simplex andthe squared distance between its circumcenter and barycenter times the squared circumradius of its inscribed simplex is not lessthan the 2(n-1)th power of n times its squared inradius, and is equal to when the simplex is regular and its inscribed siplex is atangent point one. Deduction from this inequality reaches a generalization of n-dimensional Euler inequality indicating that thecircumradius of the simplex is not less than the n-fold inradius. Another inequality is derived to present the relationship betweenthe circumradius of the n-dimensional simplex and the circumradius and inradius of its pedal simplex. 相似文献