Novel macrocyclic polyamine La(III) complexes have been synthesized.The hydrolysis of plasmid DNA(pUC18) by macrocyclic polyamine La(III) complexes has been investigated by using agarose gel electrophoresis method.The...Novel macrocyclic polyamine La(III) complexes have been synthesized.The hydrolysis of plasmid DNA(pUC18) by macrocyclic polyamine La(III) complexes has been investigated by using agarose gel electrophoresis method.The results indicated that these La(III) complexes could effectively promote the cleavage of plasmid DNA(pUC18) at physiological pH and temperature.展开更多
With the goal of constructing a carbon‐free energy cycle,proton‐exchange membrane(PEM)water electrolysis is a promising technology that can be integrated effectively with renewable energy resources to produce high‐...With the goal of constructing a carbon‐free energy cycle,proton‐exchange membrane(PEM)water electrolysis is a promising technology that can be integrated effectively with renewable energy resources to produce high‐purity hydrogen.IrO2,as a commercial electrocatalyst for the anode side of a PEM water electrolyzer,can both overcome the high corrosion conditions and exhibit efficient catalytic performance.However,the high consumption of Ir species cannot meet the sustainable development and economic requirements of this technology.Accordingly,it is necessary to understand the OER catalytic mechanisms for Ir species,further designing new types of low‐iridium catalysts with high activity and stability to replace IrO2.In this review,we first summarize the related catalytic mechanisms of the acidic oxygen evolution reaction(OER),and then provide general methods for measuring the catalytic performance of materials.Second,we present the structural evolution results of crystalline IrO2 and amorphous IrOx using in situ characterization techniques under catalytic conditions to understand the common catalytic characteristics of the materials and the possible factors affecting the structural evolution characteristics.Furthermore,we focus on three types of common low‐iridium catalysts,including heteroatom‐doped IrO2(IrOx)‐based catalysts,perovskite‐type iridium‐based catalysts,and pyrochlore‐type iridium‐based catalysts,and try to correlate the structural features with the intrinsic catalytic performance of materials.Finally,at the end of the review,we present the unresolved problems and challenges in this field in an attempt to develop effective strategies to further balance the catalytic activity and stability of materials under acidic OER catalytic conditions.展开更多
Pyrolysis gas chromatography is not a comprehensive analysis method for the determination of acrylics. Polar acrylic monomers show low abundance by gas chromatography. Because of this, a home-made pyrolysis liquid chr...Pyrolysis gas chromatography is not a comprehensive analysis method for the determination of acrylics. Polar acrylic monomers show low abundance by gas chromatography. Because of this, a home-made pyrolysis liquid chromatographic injector by means of cryogenic-focussing is developed to determine the presence and concentration of hydroxyl and carboxyl functional monomers present in water- and solvent-borne acrylics. We have shown the prove-of-principle of using cryogenic-focussing for UPLC （pyrolysis-ultra-performance liquid chromatography） injection.展开更多
The pyrolysis properties of five different pyrolysis tars, which the tars from 1# to 5# are obtained by pyrolyzing the sewage sludges of anaerobic digestion and indigestion from the A2/O wastewater treatment process, ...The pyrolysis properties of five different pyrolysis tars, which the tars from 1# to 5# are obtained by pyrolyzing the sewage sludges of anaerobic digestion and indigestion from the A2/O wastewater treatment process, those from the activated sludge process and the indigested sludge from the continuous SBR process respectively, were studied by thermal gravimetric analysis at a heating rate of 10 ℃/min in the nitrogen atmosphere. The results show that the pyrolysis processes of the pyrolysis tars of 1#, 2#, 3# and 5# all can be divided into four stages: the stages of light organic compounds releasing, heavy polar organic compounds decomposition, heavy organic compounds decomposition and the residual organic compounds decomposition. However, the process of 4# pyrolysis tar is only divided into three stages: the stages of light organic compounds releasing, decomposition of heavy polar organic compounds and the residual heavy organic compounds respectively. Both the sludge anaerobic digestion and the "anaerobic" process in wastewater treatment processes make the content of light organic compounds in tars decrease, but make that of heavy organic compounds with complex structure increase. Besides, both make the pyrolysis properties of the tars become worse. The pyrolysis reaction mechanisms of the five pyrolysis tars have been studied with Coats-Redfern equation. It shows that there are the same mechanism functions in the first stage for the five tars and in the second and third stage for the tars of 1#, 2#, 3# and 5#, which is different with the function in the second stage for 4# tar. The five tars are easy to volatile.展开更多
Neuroligins （Nlgs） are transmembrane cell adhesion molecules playing essential roles in synapse development and function. Genetic mutations in neuroUgin genes have been linked with some neurodevelopmental disorders ...Neuroligins （Nlgs） are transmembrane cell adhesion molecules playing essential roles in synapse development and function. Genetic mutations in neuroUgin genes have been linked with some neurodevelopmental disorders such as autism. These mutated Nlgs are mostly retained in the endoplasmic reticulum （ER）. However, the mechanisms underlying normal Nlg maturation and trafficking have remained largely unknown. Here, we found that Drosophila neuroligin 2 （DNlg2） undergoes proteolytic cleavage in the ER in a variety of Drosophila tissues throughout developmental stages. A region encompassing Y642-T698 is required for this process. The immature non-cleavable DNtg2 is retained in the ER and non-functionaL The C-terminal fragment of DNlg2 instead of the full-length or non-cleavable DNIg2 is able to rescue neuromuscular junction defects and GluRIIB reduction induced by dnlg2 deletion. Intriguingly, the autism-associated R598C mutation in DNIg2 leads to similar marked defects in DNIg2 proteo- lytic process and ER export, revealing a potential role of the improper Nlg cleavage in autism pathogenesis. Collectively, our find- ings uncover a specific mechanism that controls DNIg2 maturation and trafficking via proteolytic cleavage in the ER, suggesting that the perturbed proteolytic cleavage of Nlgs likely contributes to autism disorder.展开更多
文摘Novel macrocyclic polyamine La(III) complexes have been synthesized.The hydrolysis of plasmid DNA(pUC18) by macrocyclic polyamine La(III) complexes has been investigated by using agarose gel electrophoresis method.The results indicated that these La(III) complexes could effectively promote the cleavage of plasmid DNA(pUC18) at physiological pH and temperature.
文摘With the goal of constructing a carbon‐free energy cycle,proton‐exchange membrane(PEM)water electrolysis is a promising technology that can be integrated effectively with renewable energy resources to produce high‐purity hydrogen.IrO2,as a commercial electrocatalyst for the anode side of a PEM water electrolyzer,can both overcome the high corrosion conditions and exhibit efficient catalytic performance.However,the high consumption of Ir species cannot meet the sustainable development and economic requirements of this technology.Accordingly,it is necessary to understand the OER catalytic mechanisms for Ir species,further designing new types of low‐iridium catalysts with high activity and stability to replace IrO2.In this review,we first summarize the related catalytic mechanisms of the acidic oxygen evolution reaction(OER),and then provide general methods for measuring the catalytic performance of materials.Second,we present the structural evolution results of crystalline IrO2 and amorphous IrOx using in situ characterization techniques under catalytic conditions to understand the common catalytic characteristics of the materials and the possible factors affecting the structural evolution characteristics.Furthermore,we focus on three types of common low‐iridium catalysts,including heteroatom‐doped IrO2(IrOx)‐based catalysts,perovskite‐type iridium‐based catalysts,and pyrochlore‐type iridium‐based catalysts,and try to correlate the structural features with the intrinsic catalytic performance of materials.Finally,at the end of the review,we present the unresolved problems and challenges in this field in an attempt to develop effective strategies to further balance the catalytic activity and stability of materials under acidic OER catalytic conditions.
文摘Pyrolysis gas chromatography is not a comprehensive analysis method for the determination of acrylics. Polar acrylic monomers show low abundance by gas chromatography. Because of this, a home-made pyrolysis liquid chromatographic injector by means of cryogenic-focussing is developed to determine the presence and concentration of hydroxyl and carboxyl functional monomers present in water- and solvent-borne acrylics. We have shown the prove-of-principle of using cryogenic-focussing for UPLC （pyrolysis-ultra-performance liquid chromatography） injection.
基金supported by the project of Tianjin higher education under contract (20060522)the project of Tianjin Polytechnic University (2230004)
文摘The pyrolysis properties of five different pyrolysis tars, which the tars from 1# to 5# are obtained by pyrolyzing the sewage sludges of anaerobic digestion and indigestion from the A2/O wastewater treatment process, those from the activated sludge process and the indigested sludge from the continuous SBR process respectively, were studied by thermal gravimetric analysis at a heating rate of 10 ℃/min in the nitrogen atmosphere. The results show that the pyrolysis processes of the pyrolysis tars of 1#, 2#, 3# and 5# all can be divided into four stages: the stages of light organic compounds releasing, heavy polar organic compounds decomposition, heavy organic compounds decomposition and the residual organic compounds decomposition. However, the process of 4# pyrolysis tar is only divided into three stages: the stages of light organic compounds releasing, decomposition of heavy polar organic compounds and the residual heavy organic compounds respectively. Both the sludge anaerobic digestion and the "anaerobic" process in wastewater treatment processes make the content of light organic compounds in tars decrease, but make that of heavy organic compounds with complex structure increase. Besides, both make the pyrolysis properties of the tars become worse. The pyrolysis reaction mechanisms of the five pyrolysis tars have been studied with Coats-Redfern equation. It shows that there are the same mechanism functions in the first stage for the five tars and in the second and third stage for the tars of 1#, 2#, 3# and 5#, which is different with the function in the second stage for 4# tar. The five tars are easy to volatile.
文摘Neuroligins （Nlgs） are transmembrane cell adhesion molecules playing essential roles in synapse development and function. Genetic mutations in neuroUgin genes have been linked with some neurodevelopmental disorders such as autism. These mutated Nlgs are mostly retained in the endoplasmic reticulum （ER）. However, the mechanisms underlying normal Nlg maturation and trafficking have remained largely unknown. Here, we found that Drosophila neuroligin 2 （DNlg2） undergoes proteolytic cleavage in the ER in a variety of Drosophila tissues throughout developmental stages. A region encompassing Y642-T698 is required for this process. The immature non-cleavable DNtg2 is retained in the ER and non-functionaL The C-terminal fragment of DNlg2 instead of the full-length or non-cleavable DNIg2 is able to rescue neuromuscular junction defects and GluRIIB reduction induced by dnlg2 deletion. Intriguingly, the autism-associated R598C mutation in DNIg2 leads to similar marked defects in DNIg2 proteo- lytic process and ER export, revealing a potential role of the improper Nlg cleavage in autism pathogenesis. Collectively, our find- ings uncover a specific mechanism that controls DNIg2 maturation and trafficking via proteolytic cleavage in the ER, suggesting that the perturbed proteolytic cleavage of Nlgs likely contributes to autism disorder.
