This article investigates the variations of contamination levels of heavy metals such as copper, lead, chromium, cadmium, zinc, arsenic, and mercury over time in surface sediments of the Changjiang River Estuary （CRE...This article investigates the variations of contamination levels of heavy metals such as copper, lead, chromium, cadmium, zinc, arsenic, and mercury over time in surface sediments of the Changjiang River Estuary （CRE）, Yellow River Estuary （YRE）, Pearl River Estuary （PRE）, and their adjacent coastal areas in China. The contamination factor （CF）, pollution load index （PLI）, and geoaccumulation index （Igeo） are used to evaluate the quality of the surface sediments in the study areas. The results showed that the CRE, YRE, and their adjacent coastal areas were at a low risk of contamination in terms of heavy metals, while the PRE and its adjacent coastal area were at a moderate level. By comparison, the concentrations of heavy metals in the surface sediments of the YRE and its adjacent coastal area were relatively lower than those in the CRE, PRE, and their adjacent coastal areas.展开更多
In this note, we report a novel and efficient three primers PCR (TP-PCR) method to rapidly generate recombinant DNA molecule at precise junction between two arbitrary DNA fragments. TP-PCR method is characterized by i...In this note, we report a novel and efficient three primers PCR (TP-PCR) method to rapidly generate recombinant DNA molecule at precise junction between two arbitrary DNA fragments. TP-PCR method is characterized by its reaction system with two templates and three primers, which can produce a recombinant DNA molecule in one PCR reaction. The main advantages of this method are the independence of sequences at the recombination site, the rapid-ness, and the easy establishment of adequate conditions. This method has been successfully applied to constructing a fusion protein gene, sck gene.展开更多
基金supported by the National Natural Science Foundation of China(52172223,52272230,and 51972223)the Young Elite Scientists Sponsorship Program by Tianjin(TJSQNTJ-202011)+3 种基金the National Key Research and Development Program of China(2021YFF0500600 and 2022YFB2404500)the National IndustryEducation Integration Platform of Energy Storagethe Haihe Laboratory of Sustainable Chemical Transformationsthe Fundamental Research Funds for the Central Universities。
文摘This article investigates the variations of contamination levels of heavy metals such as copper, lead, chromium, cadmium, zinc, arsenic, and mercury over time in surface sediments of the Changjiang River Estuary （CRE）, Yellow River Estuary （YRE）, Pearl River Estuary （PRE）, and their adjacent coastal areas in China. The contamination factor （CF）, pollution load index （PLI）, and geoaccumulation index （Igeo） are used to evaluate the quality of the surface sediments in the study areas. The results showed that the CRE, YRE, and their adjacent coastal areas were at a low risk of contamination in terms of heavy metals, while the PRE and its adjacent coastal area were at a moderate level. By comparison, the concentrations of heavy metals in the surface sediments of the YRE and its adjacent coastal area were relatively lower than those in the CRE, PRE, and their adjacent coastal areas.
基金This work was supported by the National High Science and Technology Program "863" (Grant Nos. 2001AA212041 and 2001AA222251)the National Natural Science Foundation of China (Grant No. 39989001)the National Special Program for Research and Industr
文摘In this note, we report a novel and efficient three primers PCR (TP-PCR) method to rapidly generate recombinant DNA molecule at precise junction between two arbitrary DNA fragments. TP-PCR method is characterized by its reaction system with two templates and three primers, which can produce a recombinant DNA molecule in one PCR reaction. The main advantages of this method are the independence of sequences at the recombination site, the rapid-ness, and the easy establishment of adequate conditions. This method has been successfully applied to constructing a fusion protein gene, sck gene.
