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Distribution and degradation kinetics of cyhalodiamide in Chinese rice field environment
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作者 Yiping Liu Ya Zhang +5 位作者 Shuangqing Liu Yuntao Ronghua Lin Min Li Xiaolan Liao Xiaogang Li 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2018年第10期2185-2191,共7页
Cyhalodiamide 是对鳞翅目害虫有效的新奇农业化肥,包括 Cnaphalocrocis medinalis, Chilo suppressalis, Pieris rapae, Plutella xylostella, Helicoverpa armigera,等等。在学习,一个快、精确的分析方法被开发由修改 QuEChERS... Cyhalodiamide 是对鳞翅目害虫有效的新奇农业化肥,包括 Cnaphalocrocis medinalis, Chilo suppressalis, Pieris rapae, Plutella xylostella, Helicoverpa armigera,等等。在学习,一个快、精确的分析方法被开发由修改 QuEChERS 在中国典型稻田环境检测 cyhalodiamide (快,容易,便宜地有效,崎岖,安全) 有 UPLC-MS/MS 的方法(超离频表演层析双人脚踏车团 spectrometry ) 。cyhalodiamide 的吝啬的恢复从 73.5% ~ 107.5% 变化了,与从 1.2% ~ 10.7% 的 RSD。决心(LOD ) 的限制是 0.0005mg  展开更多
关键词 环境检测 稻田 中国 动力学 分发 鳞翅目害虫 农业化肥 ECH
Interaction between austein-ferrite phases on passive performance of 2205 duplex stainless steel
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作者 Xuequn Cheng Yi Wang +1 位作者 Xiaogang Li Chaofang Dong 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2018年第11期2140-2148,共9页
2205 双不锈钢(决策支持系统) 和它的个人的被动行为分阶段执行(-phase,-phase) 在中立 3.5% NaCl 答案被各种各样的电气化学的方法调查。结果显示了那流电的效果在之间和阶段不能败坏本地腐蚀,而是帮助被动电影的改进。在流电的效果... 2205 双不锈钢(决策支持系统) 和它的个人的被动行为分阶段执行(-phase,-phase) 在中立 3.5% NaCl 答案被各种各样的电气化学的方法调查。结果显示了那流电的效果在之间和阶段不能败坏本地腐蚀,而是帮助被动电影的改进。在流电的效果下面,溶解被动阳离子的散开将在一个短远处在之间和地区被支持,导致化学作文和被动电影并且因此的 semiconductive 性质的修正决策支持系统 2205 的腐蚀抵抗的改进。 展开更多
关键词 不锈钢 相互作用 铁酸盐 决策支持系统 性能 电气化学 NACL 阳离子
Chemo-and Biostratigraphy of the Jurassic Oil Shales from the Qiangtang Basin,Northern Tibet,China:A Case Study of the Toarcian Oceanic Anoxic Event 预览
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作者 CHEN Lan XU Guiwen +4 位作者 DA Xuejuan YI Haisheng ZHU Zhangxiong HUANG Zhaohui LI Xiaogang 《地质学报:英文版》 SCIE CAS CSCD 2017年第2期630-643,共14页
Qiangtang 盆的海洋的油页岩,北西藏,在 Biluo 暴露了公司, Tuonamu, Shenglihe 和 Changsheshan 区域被相信是重要石油来源岩石。这个工作包括地分析了碳同位素,踪迹元素,和石灰质的 nannofosills,在 Qiangtang 盆的 Biluo 公... Qiangtang 盆的海洋的油页岩,北西藏,在 Biluo 暴露了公司, Tuonamu, Shenglihe 和 Changsheshan 区域被相信是重要石油来源岩石。这个工作包括地分析了碳同位素,踪迹元素,和石灰质的 nannofosills,在 Qiangtang 盆的 Biluo 公司节的炸药和瓣鳃类。器官的碳同位素显示出积极旅行结束到 2.17 ? ш 展开更多
关键词 大洋缺氧事件 羌塘盆地 生物地层 西藏北部 油页岩 化学 侏罗系 有机碳同位素
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Effects of Carbon Content and Microstructure on Corrosion Property of New Developed Steels in Acidic Salt Solutions
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作者 F. Sun X. Li X. Cheng 《金属学报:英文版》 SCIE EI CAS CSCD 2014年第1期115-123,共9页
New steels with different carbon contents were self-developed by thermo-mechanical controlled processing.The effects of the carbon content and the microstructure on the corrosion properties of new steels were investig... New steels with different carbon contents were self-developed by thermo-mechanical controlled processing.The effects of the carbon content and the microstructure on the corrosion properties of new steels were investigated by immersion test and SEM.The results indicated that the ferrite phase(both the proeutectoid and eutectoid ferrite) dissolved preferentially.Cementite reserved and accumulated on the surface.As carbon content increased,the content of ferrite decreased and cathode/anode area ratio increased.Therefore,the corrosion rate of new steels increased from 0.30 to0.90 mm/years when the carbon content rose from 0.05 to 0.13 wt%.The corrosion process of new steels was studied using electrochemical impedance spectroscopy experiments during 72 h.It indicated that the impedance modulus |Z|_(0.01) Hz of the new steels reduces with the increase of the immersion time.While the corrosion process of the new steel with 0.11 wt%C developed faster than that with 0.07 wt%C,although their |Z|_(0.01) Hz was similar at the initial stage. 展开更多
关键词 耐腐蚀性能 显微组织 碳含量 钢种 开发 盐溶液 电化学阻抗谱 酸性
^125Ⅰ粒子植入治疗人中分化胃癌裸鼠移植瘤 预览 被引量:1
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作者 邹雷 罗开元 +3 位作者 马振桓 李波 李晓刚 许建彪 《中国肿瘤临床》 CAS CSCD 北大核心 2013年第5期248-252,共5页
目的:探讨不同剂量^125Ⅰ粒子组织间植入对人中分化胃癌细胞AGS裸鼠移植瘤生长的抑制效果及机制。方法:构建20只人中分化胃癌AGS的裸鼠移植瘤模型,随机分为4组,每组5只。3个治疗组分别接受14.8MBq(A组)、22.3MBq(B组)、29.6... 目的:探讨不同剂量^125Ⅰ粒子组织间植入对人中分化胃癌细胞AGS裸鼠移植瘤生长的抑制效果及机制。方法:构建20只人中分化胃癌AGS的裸鼠移植瘤模型,随机分为4组,每组5只。3个治疗组分别接受14.8MBq(A组)、22.3MBq(B组)、29.6MBq(C组)的^125Ⅰ粒子治疗,对照组(D组)不接受治疗。绘制肿瘤生长曲线,计算抑瘤率。通过检测细胞增殖核抗原(PCNA),了解不同剂量^125Ⅰ粒子对肿瘤细胞增殖作用的影响。原位末端标记法(TUNEL)检测不同剂量^125Ⅰ粒子诱导肿瘤细胞凋亡的情况。结果:中、高剂量组肿瘤体积、重量降低明显;不同剂量组的抑瘤率分别为(A组10.65%、B组28.65%、C组37126%)。中、高剂量治疗组PCNA的表达降低明显,中、高剂量治疗组凋亡发生明显,以上各组中、高剂量组与对照组相比均有显著统计学差异(P〈0.05)。结论:高、中剂量^125Ⅰ粒子治疗中分化胃癌效果较好;诱导细胞凋亡、PCNA表达下调,可能是抑制肿瘤生长的部分原因。 展开更多
关键词 125Ⅰ粒子 近距离放疗 胃癌 植入 裸鼠
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铜绿假单胞菌PAO1Ⅲ型分泌系统新型抑制剂的合成和生物活性研究 被引量:5
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作者 张成芳 吴小刚 +8 位作者 李燕 梁翠荣 车亦舟 顾玲玲 任杰 胡昆 孙小强 Ching-Hong Yang 陈新 《有机化学》 SCIE CAS CSCD 北大核心 2013年第6期1309-1318,共10页
铜绿假单胞菌PAO1是一种革兰氏阴性机会性人类病原菌,易感染免疫受损的人群.Ⅲ型分泌系统(Type threesecretion system,T3SS)是其主要的致病因子.T3SS抑制剂的策略是抑制铜绿假单胞菌表达及分泌毒力蛋白,阻止其对宿主细胞的侵染.在一... 铜绿假单胞菌PAO1是一种革兰氏阴性机会性人类病原菌,易感染免疫受损的人群.Ⅲ型分泌系统(Type threesecretion system,T3SS)是其主要的致病因子.T3SS抑制剂的策略是抑制铜绿假单胞菌表达及分泌毒力蛋白,阻止其对宿主细胞的侵染.在一种已知T3SS抑制剂的结构基础上,设计和合成了20种α-苯氧基酰胺新衍生物,系统研究了它们的构效关系,研究表明有5种新衍生物对铜绿假单胞菌的一个效应子编码基因exoS的表达具有明显抑制作用.其中N-(2-吡啶基甲基)-2-(2,4-二氯苯氧)-丁酰胺(5r)的活性强于已知的抑制剂MBX1641,并具有很好的水溶性. 展开更多
关键词 铜绿假单胞菌 Ⅲ型分泌系统 抑制剂 合成
Characterization and Comparison of Conducting Polyaniline Synthesized by Three Different Pathways
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作者 DONG Chaofang XIAO Kui +2 位作者 CHEN Ting LI Huiyan LI Xiaogang 《武汉理工大学学报:材料科学英文版》 SCIE EI CAS 2011年第6期 1068-1072,共5页
进行的 polyaniline (PANI ) 包括微乳液,乳剂和水的答案由三条化学氧化聚合小径准备了方法被学习并且比较。他们的结构,形态学和性质用英尺红外, XRD, TEM 和 TGA 被描绘。在水的答案形成的 PANI 粒子有一种最小的尺寸和做的 HCl ... 进行的 polyaniline (PANI ) 包括微乳液,乳剂和水的答案由三条化学氧化聚合小径准备了方法被学习并且比较。他们的结构,形态学和性质用英尺红外, XRD, TEM 和 TGA 被描绘。在水的答案形成的 PANI 粒子有一种最小的尺寸和做的 HCl 启用增加他们的传导性。相反,乳剂方法准备的 PANI 粒子有最高热的稳定性和传导性和更多的订的形态学。与这二个方法更确切地说不同,微乳液途径允许与像试管的 nanostructure 形成 nanocomposite PANI。 展开更多
关键词 导电聚苯胺 表征 合成 化学氧化聚合 纳米复合材料 纳米结构 微乳液 性能特点
Correlation of E-selectin gene polymorphisms with risk of ischemic stroke A meta-analysis 预览
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作者 Qingli Sun Yu Fu Aping Sun Yanhong Shou Mei Zheng Xiaogang li Dongsheng Fan 《中国神经再生研究:英文版》 SCIE CAS CSCD 2011年第22期 1731-1735,共5页
OBJECTIVE: To investigate the association of E-selectin S128R polymorphisms with ischemic stroke. DATA SOURCES: A computer-based online search was conducted in PubMed, Elsevier, Ovid Database, the China National Knowl... OBJECTIVE: To investigate the association of E-selectin S128R polymorphisms with ischemic stroke. DATA SOURCES: A computer-based online search was conducted in PubMed, Elsevier, Ovid Database, the China National Knowledge Infrastructure, and Wanfang Database between January 1998 and December 2010. STUDY SELECTION: Case-controlled studies addressing the association of the E-selectin polymorphism and ischemic stroke were included in this review. The genotype distribution complied with the Hardy-Weinberg genetic equilibrium. The included reports were evaluated by two authors for strict quality screening. Meta-analysis software, REVMAN 5.1, was used to investigate heterogeneity, pooled odds ratio (OR) and 95% confidence interval (CI) in individual studies. MAIN OUTCOME MEASURES: Genotype and allele distributions at the E-selectin S128R site. RESULTS: Six case-controlled studies were included after screening and application of inclusion and exclusion criteria. There was no heterogeneity in the genotype and allele frequencies, and no publication bias was found. Meta-analysis of the pooled data showed that the OR value of the (AC+CC)/AA genotype was 1.93 (95% CI: 1.55-2.41, Z = 5.80, P < 0.000 01), and the OR for the C/A allele was 1.80 (95% CI: 1.47-2.22, Z = 5.59, P < 0.000 01) in the ischemic stroke group, compared with control group. Results of pooled data in Chinese subjects showed that the OR value of (AC+CC)/AA was 2.36 (95% CI: 1.68-3.31, Z = 4.99, P < 0.000 01), and the OR value of the C/A allele was 2.25 (95% CI: 1.63-3.12, Z = 4.89, P < 0.000 01). CONCLUSION: Polymorphism of E-selectin S128R was significantly associated with susceptibility to ischemic stroke; the AC and CC genotypes as well as the C allele may be factors associated with susceptibility to ischemic stroke. 展开更多
关键词 基因多态性 选择素 中风 缺血 国家知识基础设施 等位基因频率 RIS Meta分析
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改良式烟筒形回肠输尿管吻合法在原位新膀胱中的临床研究 预览 被引量:1
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作者 吴文元 李晓刚 +4 位作者 侯国军 朴敏虎 田升日 阿卜杜拉-阿利 金铁雄 《中国肿瘤临床》 CAS CSCD 北大核心 2011年第10期583-586,共4页
目的:探讨改良式烟筒形回肠输尿管末端吻合法在可控W形回肠新膀胱术中的应用和疗效.方法:对62例膀胱全切除术后可控W形回肠新膀胱术的患者,实施了改良式烟筒形回肠与输尿管末端吻合.其中12例肠系膜过短者进一步游离肛门侧的回肠,未去... 目的:探讨改良式烟筒形回肠输尿管末端吻合法在可控W形回肠新膀胱术中的应用和疗效.方法:对62例膀胱全切除术后可控W形回肠新膀胱术的患者,实施了改良式烟筒形回肠与输尿管末端吻合.其中12例肠系膜过短者进一步游离肛门侧的回肠,未去管化直接拉进盆腔与尿道吻合.结果:本组手术时间平均为300 min,术中出血量平均为500 mL;术后随访24个月,平均16个月,失访19例,死亡8例.术后1年膀胱容量平均为500 mL,残余尿量平均为0~50 mL;术后1个月内,发生肾积水8例14个肾(11.3%),但3个月后全部消失、短暂性新膀漏尿6例(9.7%)、急性肾盂肾炎4例(6.5%)、尿道狭窄5例(8.1%),经对症治疗好转.结论:改良式烟筒形回肠与输尿管末端吻合法及未去管化的肛门侧回肠与尿道吻合法,手术时间短,出血和并发症少,控尿效果好,尤其在肠系膜过短者效果良好,值得推广. 展开更多
关键词 尿路改道 回肠代膀胱 改良烟筒形 去管化 肠系膜
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Relationship between electrochemical characteristics and SCC of X70 pipeline steel in an acidic soil simulated solution 预览 被引量:2
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作者 Zhiyong LIU Xiaogang LI +2 位作者 Yingrui ZHANG Cuiwei DU Guoli ZHA 《金属学报:英文版》 SCIE EI CAS CSCD 2009年第1期 58-64,共7页
在在在中国的 Yingtan 的酸的土壤的模仿的答案的 X70 管道钢的裂开的压力腐蚀(SCC ) 用慢紧张率测试(SSRT ) 被调查, SEM 和 potentiodynamic 极化技术。实验结果显示 X70 钢高度产生使用了潜在的还原剂的 SCC,它在坚韧和易碎的骨折... 在在在中国的 Yingtan 的酸的土壤的模仿的答案的 X70 管道钢的裂开的压力腐蚀(SCC ) 用慢紧张率测试(SSRT ) 被调查, SEM 和 potentiodynamic 极化技术。实验结果显示 X70 钢高度产生使用了潜在的还原剂的 SCC,它在坚韧和易碎的骨折的损失被表明。经常的极化电流能检测 SCC 的出现。更低极化水流是很快,压力腐蚀裂开发生。SCC 机制在改变潜力是不同的。当潜力比开的电路潜力高时,,当潜力比开的电路潜力远低时,阳极的过程控制 SCC, cathodic 过程控制 SCC,并且在这二个潜力之间区域,一个联合电气化学的过程控制 SCC。应力或紧张让 synergistic 与电气化学的反应完成加速 cathodic 氢进化过程,它使 X70 管道成为钢更产生 SCC。 展开更多
关键词 X70管线钢 酸性土壤 电化学特性 细胞 慢应变速率拉伸 应力腐蚀开裂
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Properties of passive film formed on 316L / 2205 stainless steel by Mott-Schottky theory and constant current polarization method 被引量:1
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作者 CHENG XueQun LI XiaoGang DU CuiWei 《中国科学通报:英文版》 SCIE CAS 2009年第13期2239-2246,共8页
在 316L 和 2205 不锈钢上形成的被动电影的半导体性质被电气化学的阻抗光谱学(EIS ) 在高温度的醋酸学习。结果比 316L 的,和在 316L 和 2205 不锈钢上形成的被动电影分别地显示出 p 类型和 n 类型半导体行为证明 2205 的腐蚀电阻高... 在 316L 和 2205 不锈钢上形成的被动电影的半导体性质被电气化学的阻抗光谱学(EIS ) 在高温度的醋酸学习。结果比 316L 的,和在 316L 和 2205 不锈钢上形成的被动电影分别地显示出 p 类型和 n 类型半导体行为证明 2205 的腐蚀电阻高。破坏并且被动电影自行修整被使用经常的当前的极化方法学习。当破坏比批评程度低或它不做时,结果证明为 316L,自行修整的过程将发生;为 2205,自行修整的过程仅仅在破坏在象 316L 的一样的程度的一短时间发生了。 展开更多
关键词 半导体性能 不锈钢 钝化膜 膜形成 极化法 恒流 肖特基 电化学阻抗谱
The Aging Behavior of Polyurethane Adhesive in Medium 被引量:3
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作者 NI Xiaoxue LI Xiaogang +1 位作者 ZHANG Sanping QIU Dajian 《武汉理工大学学报:材料科学英文版》 SCIE EI CAS 2009年第6期892-895,共4页
在媒介的聚氨酯粘合剂的变老的行为借助于扫描电子显微镜学(SEM ) 被调查并且比较,红外线的光谱学(红外) ,接口分析和砍的力量测试。试验性的结果证明在盐水的聚氨酯粘合剂的 shear 力量在水里比那更快速被减少。Na <sup>+</... 在媒介的聚氨酯粘合剂的变老的行为借助于扫描电子显微镜学(SEM ) 被调查并且比较,红外线的光谱学(红外) ,接口分析和砍的力量测试。试验性的结果证明在盐水的聚氨酯粘合剂的 shear 力量在水里比那更快速被减少。Na <sup>+</sup> 和 Cl <sup>&#8722;</sup> 离子能使聚氨酯成为更快的粘合剂年龄和接口金属腐蚀。高温度加速水分子, Na <sup>+</sup> 和 Cl <sup>&#8722;</sup> 离子和巨大的分子的降级的散开。 展开更多
关键词 聚氨酯胶粘剂 老化行为 界面剪切强度 扫描电子显微镜 红外光谱 测试手段 金属腐蚀 速度比
Mechanical assisted electroless barrel-plating Ni-P coatings on magnesium alloy 预览 被引量:4
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作者 Zhaoxia PING Juntao YUAN Yedong HE Xiaogang LI 《金属学报:英文版》 SCIE EI CAS CSCD 2009年第3期 225-232,共8页
一块机械地帮助的无电的桶小块地捏在包含 Mg 合金标本和陶器的球的滚动的鼓被执行,它在包含无电的 plating 的洗澡被沉没答案。这种新奇技术扔的 Ni-P 涂层有,这被表明一结晶捏稳固的答案结构,与常规无电的 plated 相比显示出好谷... 一块机械地帮助的无电的桶小块地捏在包含 Mg 合金标本和陶器的球的滚动的鼓被执行,它在包含无电的 plating 的洗澡被沉没答案。这种新奇技术扔的 Ni-P 涂层有,这被表明一结晶捏稳固的答案结构,与常规无电的 plated 相比显示出好谷物的、更高的坚硬,和更高的腐蚀抵抗非结晶捏涂层。在在为 1 h 的 400 C 的热处理以后,这的结构捏涂层与 Ni-Ni3P 双阶段被转变到结构,并且在这些涂层裂开能观察的 not-be,而裂缝在常规无电的 plated 严重出现了,在一样的热处理以后捏涂层。因此,坚硬和这些的腐蚀抵抗捏涂层能被热处理进一步改进。所有能在机械地帮助的无电的桶小块地过程期间这些有益的效果被归因于机械摩擦的角色。 展开更多
关键词 化学镀NI 机械研磨 镁合金 涂层 耐腐蚀性能 助镀 结构转变 电镀工艺
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Effect of deteriorated microstructures on stress corrosion cracking of X70 pipeline steel in acidic soil environment 预览 被引量:2
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作者 Zhiyong Liu GuoLi Zhai Xiaogang Li Cuiwei Du 《北京科技大学学报:英文版》 CSCD 2008年第6期 707-713,共7页
In order to investigate stress corrosion cracking (SCC) of X70 pipeline steel and its weld joint area in acidic soil environ-ment in China, two simulating methods were used: one was to obtain bad microstructures in he... In order to investigate stress corrosion cracking (SCC) of X70 pipeline steel and its weld joint area in acidic soil environ-ment in China, two simulating methods were used: one was to obtain bad microstructures in heat affected zone by annealing at 1300°C for 10 min and then, quenching in water; the other was to get different simulating solutions of acidic soil in Yingtan in south-east China. The SCC susceptibilities of X70 pipeline steel before and after quenching in the simulating solutions were analyzed using slow stain rate test (SSRT) and potentiodynamic polarization technique to investigate the SCC electrochemical mechanism of differ-ent microstructures further. The results show that SCC appears in the original microstructure and the quenched microstructure as the polarization potential decreases. Hydrogen revolution accelerates SCC of the two tested materials within the range of -850 mV to -1200 mV vs. SCE. Microstructural hardening and grain coarsening also increase SCC. The SCC mechanisms are different, anodic dissolution is the key of causing SCC as the polarization potential is higher than the null current potential, and hydrogen embrittle-ment will play a more important role to SCC as the polarization potential lower than the null current potential. 展开更多
关键词 退火 淬火 热处理 X70板材钢
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Effects of Cl^- and SO4^2- Ions on Corrosion Behavior of X70 Steel 预览 被引量:1
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作者 JunweiWU XiaogangLI +2 位作者 CuiweiDU SongWANG YiquanSONG 《材料科学技术:英文版》 SCIE EI CAS CSCD 2005年第1期28-32,共5页
Corrosion behaviors of X70 steel were studied by means of electrochemical experiments and morphology observation.First, through potentiodynamic polarization in solution of various Cl^- ions concentration, it was found... Corrosion behaviors of X70 steel were studied by means of electrochemical experiments and morphology observation.First, through potentiodynamic polarization in solution of various Cl^- ions concentration, it was found that Epit began to appear in solution of Cl^- concentration above 0.1 mol/L, and there was a critical point of Cl^- concentration between 0.05 mol/L and 0.1 mol/L, below which the extent of pitting and general corrosion were trivial, while in solution of Cl^- concentration above 0.1 mol/L, general and pitting corrosion became greater as the increasing of Cl^- concentration. All of them were confirmed by the SEM observations after anodic polarization. Second, via the potentiodynamic polarization curves of X70 steel in 0.5 mol/L Cl^- solution with 0, 0.05, 0.5 and 1 mol/L SO4^2- ions, it was found SO4^2- ions were able to inhibit corrosion aroused from Cl^- ions, accordingly a model was set up to describe the process. In addition, to further explore the inhibited effect of SO4^2- ions, EIS was used in solutions of different Cl^- and SO4^2- concentrations, the results revealed that the electrochemical resistance has a relation with the [SO4^2-]/[Cl^-], that was, the bigger the value of [SO4^2-]/[Cl^-], the greater the electrochemical resistance. 展开更多
关键词 X70钢 氯离子 硫酸根离子 蚀斑 全面腐蚀
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Healing of hydrogen-attacked cracks in split specimens with recovering heat treatment in vacuum 预览
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作者 JingXu ChaofangDong XiaogangLi 《北京科技大学学报:英文版》 CSCD 2004年第3期 245-250,共6页
The healing mechanism of hydrogen-attacked cracks in low carbon steel and Cr-Mo steel and its influencing factors during the healing process were studied by recovering heat treatment of split specimens in vacuum. The ... The healing mechanism of hydrogen-attacked cracks in low carbon steel and Cr-Mo steel and its influencing factors during the healing process were studied by recovering heat treatment of split specimens in vacuum. The result showed that crack pacing tums much smaller under the condition of pure heating, especially for crack tips. The healing effect is well related to the length of cracks with the shorter in priority. By the primary mechanism of thermal diffusion, iron and carbon atoms must diffuse at the high speed in steel to realize that plasticity deformation energy exceeds and overcomes surface tensile force energy. In addition, phase transformation and stress-stain relationship also have positive effects on the process. 展开更多
关键词 氢腐蚀 裂缝 修复 热处理 真空
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Initial corrosion behaviors of AZ91 magnesium alloy in the presence of SO2 预览
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作者 CuiLin XiaogangLi 《北京科技大学学报:英文版》 CSCD 2004年第5期 433-441,共9页
The effects of SO2 on the initial atmospheric corrosion of AZ91D magnesium alloy were investigated in laboratory. Metallographic observation, SEM (Scanning Electron Microscopy), XRD (X-ray Diffraction) and XPS (X-ray ... The effects of SO2 on the initial atmospheric corrosion of AZ91D magnesium alloy were investigated in laboratory. Metallographic observation, SEM (Scanning Electron Microscopy), XRD (X-ray Diffraction) and XPS (X-ray Proton Spectrograph) were used to analyze and discuss the initial surface morphology of corrosion layers and corrosion products. The corrosion rate of the alloy increases with increasing the content of SO2. The initial attack has the characteristics of localized corrosion and preferentially concentrates on α phase. MgO and Mg(OH)2 form at first, which provide a protective layer, then the existence of SO2 decreases the pH of the thin solution on the alloy, accelerates dissolution process, and promotes the formation of MgSO3·6H20 and MgSO4·6H20,meanwhile cracks were found on the corrosion products with corrosion continuation. These soluble corrosion products and the cracks provide the paths for filtering oxygen and corrosion pollutants into the matrix, which results in severe localized corrosion and the loss of protective function of film. 展开更多
关键词 SO2 MG(OH)2 AZ91D SEM XRD XPS
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Effect of hydrogen attack on acoustic emission behavior of low carbon steel 预览 被引量:1
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作者 XiaogangLi ChaofangDong 《北京科技大学学报:英文版》 CSCD 2002年第2期 130-134,共5页
In order to investigate the effect of hydrogen attack degree on acoustic emission (AE) behavior of low carbon steel during tensiling, specimens made of low carbon steel was exposed to hydrogen gas of 18 MPa at 450 and... In order to investigate the effect of hydrogen attack degree on acoustic emission (AE) behavior of low carbon steel during tensiling, specimens made of low carbon steel was exposed to hydrogen gas of 18 MPa at 450 and 500℃ for 240, 480 and 720 h respectively. Experimental results show that with increase of the hydrogen attack degree, the totally AE activity decreases during tensiling. In addition, the count of AE signals with high amplitude for the specimens with hydrogen attack keeps a constant which is less than that without hydrogen attack. It is concluded that AE signals originate in the specimens with hydrogen attack from intergranular fracture induced by methane blisterings or/and microcracks on grain boundaries. 展开更多
关键词 低碳钢 氢脆 声发射
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Anaerobic microbiologically influenced corrosion mechanisms interpreted using bioenergetics and bioelectrochemistry: A review
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作者 Yingchao Li Dake Xu +6 位作者 Changfeng Chen Xiaogang Li Ru Jia Dawei Zhang Wolfgang Sand Fuhui Wang Tingyue Cu 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2018年第10期1713-1718,共6页
微生物学地影响的腐蚀(MIC ) 是腐蚀损坏,设备失败,和金融损失的一个主要原因,使 MIC 成为一个重要研究话题。由于复杂 microbiological 活动和在 biofilms 和金属表面之间的相互作用的深理解的缺乏, MIC 出现和机制是困难的预言并... 微生物学地影响的腐蚀(MIC ) 是腐蚀损坏,设备失败,和金融损失的一个主要原因,使 MIC 成为一个重要研究话题。由于复杂 microbiological 活动和在 biofilms 和金属表面之间的相互作用的深理解的缺乏, MIC 出现和机制是困难的预言并且解释。许多理论和机制被建议了解释 MIC。在这评论, MIC 的机制用 bioenergetics,微生物引起的呼吸类型,和 biofilm 被讨论细胞外的电子转移(EET ) 。二种主要 MIC 类型,也就是 EET-MIC 和代谢物 MIC (M-MIC ) ,被讨论。这简短评论提供现状卓见进 MIC 机制,它在油和煤气的工业在厌氧的条件下面帮助 MIC 的出现的诊断和预言。 展开更多
关键词 腐蚀机制 微生物学 评论 地影 厌氧 MIC 呼吸类型 腐蚀损坏
Effect of Microstructures on Corrosion Behavior of Nickel Coatings: (II) Competitive Effect of Grain Size and Twins Density on Corrosion Behavior
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作者 Guozhe Meng Yang Li +6 位作者 Yawei Shao Tao Zhang Yanqiu Wang Fuhui Wang Xuequn Cheng Chaofang Dong Xiaogang Li 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2016年第5期465-469,共5页
有 50 &thinsp;nm 的谷物尺寸的 Nanocrystalline 镍涂层为 10 &thinsp;min 在 200 &thinsp;&deg;C 和 400 &thinsp;&deg;C 在真空被退火。他们的微观结构被传播电子显微镜学(TEM ) 调查。并且他们的腐蚀行为... 有 50 &thinsp;nm 的谷物尺寸的 Nanocrystalline 镍涂层为 10 &thinsp;min 在 200 &thinsp;&deg;C 和 400 &thinsp;&deg;C 在真空被退火。他们的微观结构被传播电子显微镜学(TEM ) 调查。并且他们的腐蚀行为借助于极化和电气化学的阻抗光谱学(EIS ) 被学习。结果证明他们的谷物分别地判断 grow 到大约 60 &thinsp;nm (200 &thinsp;&deg;C ) 和 500 &thinsp;nm (400 &thinsp;&deg;C ) 。标本在更高拥有的 200 &thinsp;&deg;C 退火了双胞胎在的密度与对应物相比在 400 &thinsp;&deg;C 同样扔、退火。腐蚀行为上的正常谷物尺寸效果没被观察。然而,涂层的腐蚀抵抗线性地随着双胞胎的密度变化了,这被发现。 展开更多
关键词 腐蚀行为 晶粒尺寸 高密度 竞争效应 孪晶 镍镀层 微结构 真空退火处理
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