The arbitrary discharge of tetracycline(TC)residuals has seriously influenced the ecosystem and human health.Laccase(Lac)-based biodegradation technology is considered a more effective way to remove TC due to its high...The arbitrary discharge of tetracycline(TC)residuals has seriously influenced the ecosystem and human health.Laccase(Lac)-based biodegradation technology is considered a more effective way to remove TC due to its high catalytic efficiency and less by-product.Nevertheless,free Lac suffers from poor stability,easy inactivation and difficult recovery,restricting its application.Immobilization of Lac is considered an efficient strategy for addressing these obstacles.In this study,a magnetic metal-organic framework of Fe_(3)O_(4)@SiO_(2)@UiO-66-NH_(2)(MMOF)was prepared and used as a carrier to immobilize Lac(Lac@MMOF)for TC degradation.Benefiting from the multiple binding sites,adsorption,and protection effect of MMOF,Lac@MMOF displayed a wider pH application range(2–7)and better thermal(15–85℃),repeatability,and storage stability than free Lac.Furthermore,owing to the synergism of MOF adsorption and Lac biocatalysis,the removal rate of Lac@MMOF for TC could be up to 98%at pH=7 within 1 hr,which was 1.29 and 1.24 times that of free Lac and MMOF,respectively.More importantly,Lac@MMOF could easily be separated from aqueous solution under a magnetic field and maintained good removal performance(80%)after five cycles.The degradation products were identified by applying LC-MS/MS,and possible degradation mechanisms and pathways were proposed.Finally,the antibacterial activity of intermediate products was evaluated using Escherichia coli,which revealed that the toxicity of TC was reduced effectively by the degradation of Lac@MMOF.Overall,Lac@MMOF is a green alternative for residual antibiotic removal in water.展开更多
On September 1st,the 18th Chi na-LAC Business Summit Promotion Conference opened in Beijing.Chinese and foreign vips gathered to prepare for the 18th China LAC Business Summit,planned for Zhengzhou,Henan,from Novemb...On September 1st,the 18th Chi na-LAC Business Summit Promotion Conference opened in Beijing.Chinese and foreign vips gathered to prepare for the 18th China LAC Business Summit,planned for Zhengzhou,Henan,from November 3rd to 4th.展开更多
Zhengzhou,located at the eastern foot of Mount Song and along the banks of the Yel low River,sits at the heart of China.It is the capital of Henan Province and one of China’s eight great ancient capitals.Historically...Zhengzhou,located at the eastern foot of Mount Song and along the banks of the Yel low River,sits at the heart of China.It is the capital of Henan Province and one of China’s eight great ancient capitals.Historically known as the“Center of Heaven and Earth”,it is now praised as the“Green City”As a national central city expl icit ly suppor ted by the Chinese government and a core growth pole for high-quality regional development.展开更多
In this study,the apsidal motion analyses of the eclipsing binary systems V398 Lac,V2544 Cyg,and V785 Cas are presented.The(O-C)diagrams of the selected systems were constructed using all available and reliable times ...In this study,the apsidal motion analyses of the eclipsing binary systems V398 Lac,V2544 Cyg,and V785 Cas are presented.The(O-C)diagrams of the selected systems were constructed using all available and reliable times of minimum light compiled from the literature.As a result,the apsidal motion periods were determined to be 353±50 yr,43.3±5.1 yr and 83.4±8.5 yr,respectively.Furthermore,the TESS light curves of the three systems were analyzed to derive their photometric and absolute parameters.The component masses were determined as follows:for V398 Lac,M_(1)=3.83±0.35 M_(⊙)and M2=3.27±0.35 M_(⊙);for V2544 Cyg,M_(1)=1.75±0.38 M_(⊙)and M2=1.40±0.38 M_(⊙);for V785 Cas,M_(1)=5.64±0.41 M_(⊙)and M2=5.18±0.41 M_(⊙).The parameters related to apsidal motion,as well as the observational and theoretical internal structure constants(K_(2,obs) and K_(2,teo))were calculated for studied binaries.The relativistic contribution to the observed apsidal motion rate was found to be relatively small,constituting less than approximately 5%of the total rate in each system.The theoretical internal structure constants were derived from the evolutionary models,assuming a standard chemical composition of(X,Z)=(0.70,0.01).展开更多
基金supported by the National Natural Science Foundation of China(No.U20A20133)the National Key Research and Development Program of China(No.2022YFF0606703).
文摘The arbitrary discharge of tetracycline(TC)residuals has seriously influenced the ecosystem and human health.Laccase(Lac)-based biodegradation technology is considered a more effective way to remove TC due to its high catalytic efficiency and less by-product.Nevertheless,free Lac suffers from poor stability,easy inactivation and difficult recovery,restricting its application.Immobilization of Lac is considered an efficient strategy for addressing these obstacles.In this study,a magnetic metal-organic framework of Fe_(3)O_(4)@SiO_(2)@UiO-66-NH_(2)(MMOF)was prepared and used as a carrier to immobilize Lac(Lac@MMOF)for TC degradation.Benefiting from the multiple binding sites,adsorption,and protection effect of MMOF,Lac@MMOF displayed a wider pH application range(2–7)and better thermal(15–85℃),repeatability,and storage stability than free Lac.Furthermore,owing to the synergism of MOF adsorption and Lac biocatalysis,the removal rate of Lac@MMOF for TC could be up to 98%at pH=7 within 1 hr,which was 1.29 and 1.24 times that of free Lac and MMOF,respectively.More importantly,Lac@MMOF could easily be separated from aqueous solution under a magnetic field and maintained good removal performance(80%)after five cycles.The degradation products were identified by applying LC-MS/MS,and possible degradation mechanisms and pathways were proposed.Finally,the antibacterial activity of intermediate products was evaluated using Escherichia coli,which revealed that the toxicity of TC was reduced effectively by the degradation of Lac@MMOF.Overall,Lac@MMOF is a green alternative for residual antibiotic removal in water.
文摘On September 1st,the 18th Chi na-LAC Business Summit Promotion Conference opened in Beijing.Chinese and foreign vips gathered to prepare for the 18th China LAC Business Summit,planned for Zhengzhou,Henan,from November 3rd to 4th.
文摘Zhengzhou,located at the eastern foot of Mount Song and along the banks of the Yel low River,sits at the heart of China.It is the capital of Henan Province and one of China’s eight great ancient capitals.Historically known as the“Center of Heaven and Earth”,it is now praised as the“Green City”As a national central city expl icit ly suppor ted by the Chinese government and a core growth pole for high-quality regional development.
基金Funding for TESS is provided by the NASA Science Mission Directorate。
文摘In this study,the apsidal motion analyses of the eclipsing binary systems V398 Lac,V2544 Cyg,and V785 Cas are presented.The(O-C)diagrams of the selected systems were constructed using all available and reliable times of minimum light compiled from the literature.As a result,the apsidal motion periods were determined to be 353±50 yr,43.3±5.1 yr and 83.4±8.5 yr,respectively.Furthermore,the TESS light curves of the three systems were analyzed to derive their photometric and absolute parameters.The component masses were determined as follows:for V398 Lac,M_(1)=3.83±0.35 M_(⊙)and M2=3.27±0.35 M_(⊙);for V2544 Cyg,M_(1)=1.75±0.38 M_(⊙)and M2=1.40±0.38 M_(⊙);for V785 Cas,M_(1)=5.64±0.41 M_(⊙)and M2=5.18±0.41 M_(⊙).The parameters related to apsidal motion,as well as the observational and theoretical internal structure constants(K_(2,obs) and K_(2,teo))were calculated for studied binaries.The relativistic contribution to the observed apsidal motion rate was found to be relatively small,constituting less than approximately 5%of the total rate in each system.The theoretical internal structure constants were derived from the evolutionary models,assuming a standard chemical composition of(X,Z)=(0.70,0.01).
