To recycle arsenic from an As-Sb fly ash,a newly continuous reductive method for obtaining elemental As with additive of PbO was proposed.In the first reduction stage,PbO promoted the As segregation from the As-Sb fly...To recycle arsenic from an As-Sb fly ash,a newly continuous reductive method for obtaining elemental As with additive of PbO was proposed.In the first reduction stage,PbO promoted the As segregation from the As-Sb fly ash,due to which most As volatilized and Sb retained in roasted residues in phases of As-Sb-Pb-O and As-Sb-Pb alloy.With the increase of PbO and reductant amounts,the Sb fixation rate increased in the first reduction stage,and further the Sb content in the elemental As obtained from the second reduction stage decreased.After being roasted for 30 min at 550℃ with the addition of 20%activated carbon and 12%PbO in the first reduction stage,the As volatilization rate and Sb fixation rate from the As-Sb fly ash reached 92.86%and 79.38%,respectively.Then through the second reduction of the volatile matters at 650℃,the As and Sb contents in the obtained elemental As reached 99.07 wt%and 0.22 wt%respectively,indicating that the obtained As could be used to prepare high purity As,thereby rendering the As-Sb fly ash recycling.展开更多
In most bacteria, plants and algae, fatty acid biosynthesis is catalyzed by a group of freely dissociable proteins known as the type II fatty acid synthase （FAS II） system. In the FAS II system, enoyl- acyl carrier ...In most bacteria, plants and algae, fatty acid biosynthesis is catalyzed by a group of freely dissociable proteins known as the type II fatty acid synthase （FAS II） system. In the FAS II system, enoyl- acyl carrier protein reductase （ENR） acts as a determinant for completing the cycles of fatty acid elongation. In this study, the cDNA sequence of ENR, designated as IgENR, was isolated from the microalga lsochrysis galbana CCMM5001. RACE （rapid amplification of cDNA ends） was used to isolate the full-length cDNA oflgENR （1 503 bp）, which contains an open reading frame （ORF） of 1 044 bp and encodes a protein of 347 amino acids. The genomic DNA sequence oflgENR is interrupted by four introns. The putative amino acid sequence is homologous to the ENRs of seed plants and algae, and they contain common coenzyme- binding sites and active site motifs. Under different stress conditions, real-time quantitative polymerase chain reaction （RT-qPCR） showed the expression oflgENR was upregulated by high temperature （35℃）, and downregulated by depleted nitrogen （0 mol/L）. To clarify the mechanism of lipids accumulating lipids, other genes involved in lipids accumulation should be studied.展开更多
基金Project(51874153) supported by the National Natural Science Foundation of ChinaProject(LZB2021003) supported by Fundamental Research Funds for the Central UniversitiesDHU Distinguished Young Professor Program,China。
文摘To recycle arsenic from an As-Sb fly ash,a newly continuous reductive method for obtaining elemental As with additive of PbO was proposed.In the first reduction stage,PbO promoted the As segregation from the As-Sb fly ash,due to which most As volatilized and Sb retained in roasted residues in phases of As-Sb-Pb-O and As-Sb-Pb alloy.With the increase of PbO and reductant amounts,the Sb fixation rate increased in the first reduction stage,and further the Sb content in the elemental As obtained from the second reduction stage decreased.After being roasted for 30 min at 550℃ with the addition of 20%activated carbon and 12%PbO in the first reduction stage,the As volatilization rate and Sb fixation rate from the As-Sb fly ash reached 92.86%and 79.38%,respectively.Then through the second reduction of the volatile matters at 650℃,the As and Sb contents in the obtained elemental As reached 99.07 wt%and 0.22 wt%respectively,indicating that the obtained As could be used to prepare high purity As,thereby rendering the As-Sb fly ash recycling.
基金Supported by the National Natural Science Foundation of China(No.41106148)the Ocean Public Welfare Scientific Research Project(Nos.GHME2001SW02,200905019,200805039)the Science and Technology Development Program of Shandong Province(No.2011GHY11533)
文摘In most bacteria, plants and algae, fatty acid biosynthesis is catalyzed by a group of freely dissociable proteins known as the type II fatty acid synthase （FAS II） system. In the FAS II system, enoyl- acyl carrier protein reductase （ENR） acts as a determinant for completing the cycles of fatty acid elongation. In this study, the cDNA sequence of ENR, designated as IgENR, was isolated from the microalga lsochrysis galbana CCMM5001. RACE （rapid amplification of cDNA ends） was used to isolate the full-length cDNA oflgENR （1 503 bp）, which contains an open reading frame （ORF） of 1 044 bp and encodes a protein of 347 amino acids. The genomic DNA sequence oflgENR is interrupted by four introns. The putative amino acid sequence is homologous to the ENRs of seed plants and algae, and they contain common coenzyme- binding sites and active site motifs. Under different stress conditions, real-time quantitative polymerase chain reaction （RT-qPCR） showed the expression oflgENR was upregulated by high temperature （35℃）, and downregulated by depleted nitrogen （0 mol/L）. To clarify the mechanism of lipids accumulating lipids, other genes involved in lipids accumulation should be studied.
