热镀锌件铬酸盐转化膜耐蚀性优良,但环境污染严重;铈盐转化膜效果差,复合铈盐转化膜耐蚀好,成本高;镧盐转化膜无毒,耐蚀效果比铈盐好。采用以La(NO3)3为主盐的成膜溶液浸泡热镀锌层,获得了La盐转化膜。通过SEM,EDS和电化学测试方法对La...热镀锌件铬酸盐转化膜耐蚀性优良,但环境污染严重;铈盐转化膜效果差,复合铈盐转化膜耐蚀好,成本高;镧盐转化膜无毒,耐蚀效果比铈盐好。采用以La(NO3)3为主盐的成膜溶液浸泡热镀锌层,获得了La盐转化膜。通过SEM,EDS和电化学测试方法对La盐转化膜层的结构和耐蚀性能进行了研究。结果表明:转化膜随浸泡时间增加而增厚,膜的极化电阻和电化学阻抗也随之增大;膜层中存在均匀分布的微裂纹,且随膜增厚而扩宽;处理时间过长,膜的表层开裂脱落,极化电阻和电化学阻抗下降。浸泡30 m in所获La盐转化膜,极化电阻和EIS低频阻抗达20 kΩ.cm2以上,耐蚀性能远高于单一铈盐转化膜,极大地提高了热镀锌件的耐蚀性能。展开更多
Pepper seedlings were hydroponically cultivated in 0-20 mg/L extraneous lanthanum chloride (La3+) for different numbers of days to investigate its regulating effects under salt stress. The results showed that, depe...Pepper seedlings were hydroponically cultivated in 0-20 mg/L extraneous lanthanum chloride (La3+) for different numbers of days to investigate its regulating effects under salt stress. The results showed that, depending on the salt stress of 0.75 g/L, a lower concentration of La3+ (1.0 rag/L) might result in the lowest death rate, increase POD activity and change the band type of the stem and root on the 8th day. Furthermore, a methylation analysis by the methylation-sensitive amplified polymorphism (MSAP) technique indicated that a lower concentration of La3+ (1.0 mg/L) triggered the lowest methylation level of 26.1%, of which the hypermethylation events were the primary type of methylation. In addition, the sequencing of 14 differ- entially expressed polymorphic fragments and the subsequent blast search revealed that La3+ could induce methylation events in salt-tolerance sequences.展开更多
文摘热镀锌件铬酸盐转化膜耐蚀性优良,但环境污染严重;铈盐转化膜效果差,复合铈盐转化膜耐蚀好,成本高;镧盐转化膜无毒,耐蚀效果比铈盐好。采用以La(NO3)3为主盐的成膜溶液浸泡热镀锌层,获得了La盐转化膜。通过SEM,EDS和电化学测试方法对La盐转化膜层的结构和耐蚀性能进行了研究。结果表明:转化膜随浸泡时间增加而增厚,膜的极化电阻和电化学阻抗也随之增大;膜层中存在均匀分布的微裂纹,且随膜增厚而扩宽;处理时间过长,膜的表层开裂脱落,极化电阻和电化学阻抗下降。浸泡30 m in所获La盐转化膜,极化电阻和EIS低频阻抗达20 kΩ.cm2以上,耐蚀性能远高于单一铈盐转化膜,极大地提高了热镀锌件的耐蚀性能。
基金Project supported by the Educational Commission Program of Anhui Province(KJ2013A074)the National Xinghuo Plan(2012GA710028)
文摘Pepper seedlings were hydroponically cultivated in 0-20 mg/L extraneous lanthanum chloride (La3+) for different numbers of days to investigate its regulating effects under salt stress. The results showed that, depending on the salt stress of 0.75 g/L, a lower concentration of La3+ (1.0 rag/L) might result in the lowest death rate, increase POD activity and change the band type of the stem and root on the 8th day. Furthermore, a methylation analysis by the methylation-sensitive amplified polymorphism (MSAP) technique indicated that a lower concentration of La3+ (1.0 mg/L) triggered the lowest methylation level of 26.1%, of which the hypermethylation events were the primary type of methylation. In addition, the sequencing of 14 differ- entially expressed polymorphic fragments and the subsequent blast search revealed that La3+ could induce methylation events in salt-tolerance sequences.