The multi-yearly averaged pentad meteorological fields at 850 hPa of theNCEP/NCAR reanalysis dada and the TBB fields of the Japan Meteorological Agency during 1980-1994 areanalyzed. It is found that if the pentad is t...The multi-yearly averaged pentad meteorological fields at 850 hPa of theNCEP/NCAR reanalysis dada and the TBB fields of the Japan Meteorological Agency during 1980-1994 areanalyzed. It is found that if the pentad is taken as the time unit of the monsoon onset, then thetropical Asian summer monsoon (TASM) onsets earliest, simultaneously and abruptly over the wholearea in the Bay of Bengal (BOB), the Indo-China Peninsula (ICP), and the South China Sea (SCS), eastof 90°E, in the 27th to 28th pentads of a year (Pentads 3 to 4 in May), while it onsets later inthe India Peninsula (IP) and the Arabian Sea (AS), west of 90°E. The TASM bursts first at the southend of the IP in the 30th to 31st pentads near 10°N, and advances gradually northward to the wholearea, by the end of June. Analysis of the possible mechanism depicts that the rapid changes of thesurface sensible heat flux, air temperature, and pressure in spring and early summer in the middleto high latitudes of the East Asian continent between 100°E and 120°E are crucially responsiblefor the earliest onset of the TASM in the BOB to the SCS areas. It is their rapid changes thatinduce a continental depression to form and break through the high system of pressure originallylocated in the above continental areas. The low depression in turn introduces the southwesterly tocome into the BOB to the SCS areas, east of 90° E, and thus makes the SCS summer monsoon (SCSSM)burst out earliest in Asia. In the IP to the AS areas, west of 90° E, the surface sensible heatflux almost does not experience obvious change during April and May, which makes the tropical Indiansummer monsoon (TISM) onset later than the SCSSM by about a month. Therefore, it is concluded thatthe meridian of 90° E is the demarcation line between the South Asian summer monsoon (SASM, i.e.,the TISM) and the East Asian summer monsoon (EASM, including the SCSSM). Besides, the temporalrelations between the TASM onset and the seasonal variation of the South Asian high (SAH) arediscussed, too, and it is foun展开更多
Five negatively charged organic compounds with different structures, sodium methane sulfonate(MS), sodium benzene sulfonate(BS), sodium 6-hydroxynaphthalene-2-sulfonate(NSS), sodium dodecyl sulfate(SDS), and sodium do...Five negatively charged organic compounds with different structures, sodium methane sulfonate(MS), sodium benzene sulfonate(BS), sodium 6-hydroxynaphthalene-2-sulfonate(NSS), sodium dodecyl sulfate(SDS), and sodium dodecyl benzene sulfonate(SDBS), were used to examine the fouling of an anion exchange membrane(AEM) in electrodialysis(ED),to explore the effect of molecular characteristics on the fouling behavior on the AEM and changes in the surface and electrochemical properties of the AEM. Results indicated that the fouling degree of the AEM by the different organics followed the order:SDBS > SDS > NSS > BS > MS. SDBS and SDS formed a dense fouling layer on the surface of the AEM, which was the main factor in the much more severe membrane fouling, and completely restricted the transmembrane ion migration. The other three organics caused fouling of the AEM by adsorption on the surface and/or accumulation in the interlayer of the AEM, and exhibited almost no influence on the transmembrane ion migration. It was also concluded that the organics with benzene rings caused more severe fouling of the AEM due to the stronger affinity interaction and steric effect between the organics and the AEM compared with organics with aliphatic chains.展开更多
基金Sponsored by the NSFC Key Project under No. 40233037the "National Key Developing Programme for Basic Science" project under No. 2004CB418300.
文摘The multi-yearly averaged pentad meteorological fields at 850 hPa of theNCEP/NCAR reanalysis dada and the TBB fields of the Japan Meteorological Agency during 1980-1994 areanalyzed. It is found that if the pentad is taken as the time unit of the monsoon onset, then thetropical Asian summer monsoon (TASM) onsets earliest, simultaneously and abruptly over the wholearea in the Bay of Bengal (BOB), the Indo-China Peninsula (ICP), and the South China Sea (SCS), eastof 90°E, in the 27th to 28th pentads of a year (Pentads 3 to 4 in May), while it onsets later inthe India Peninsula (IP) and the Arabian Sea (AS), west of 90°E. The TASM bursts first at the southend of the IP in the 30th to 31st pentads near 10°N, and advances gradually northward to the wholearea, by the end of June. Analysis of the possible mechanism depicts that the rapid changes of thesurface sensible heat flux, air temperature, and pressure in spring and early summer in the middleto high latitudes of the East Asian continent between 100°E and 120°E are crucially responsiblefor the earliest onset of the TASM in the BOB to the SCS areas. It is their rapid changes thatinduce a continental depression to form and break through the high system of pressure originallylocated in the above continental areas. The low depression in turn introduces the southwesterly tocome into the BOB to the SCS areas, east of 90° E, and thus makes the SCS summer monsoon (SCSSM)burst out earliest in Asia. In the IP to the AS areas, west of 90° E, the surface sensible heatflux almost does not experience obvious change during April and May, which makes the tropical Indiansummer monsoon (TISM) onset later than the SCSSM by about a month. Therefore, it is concluded thatthe meridian of 90° E is the demarcation line between the South Asian summer monsoon (SASM, i.e.,the TISM) and the East Asian summer monsoon (EASM, including the SCSSM). Besides, the temporalrelations between the TASM onset and the seasonal variation of the South Asian high (SAH) arediscussed, too, and it is foun
基金supported by the National Natural Science Foundation of China(Nos.51878645 and 51425405)the Science and Technology Open Cooperation Project of Henan Province(No.172106000076)+2 种基金the Beijing Natural Science Foundation(No.8132047)the Major Science and Technology Program for Water Pollution Control and Treatment(Nos.2014ZX07201-011 and 2014ZX07510-001)financial support from the China Scholarship Council
文摘Five negatively charged organic compounds with different structures, sodium methane sulfonate(MS), sodium benzene sulfonate(BS), sodium 6-hydroxynaphthalene-2-sulfonate(NSS), sodium dodecyl sulfate(SDS), and sodium dodecyl benzene sulfonate(SDBS), were used to examine the fouling of an anion exchange membrane(AEM) in electrodialysis(ED),to explore the effect of molecular characteristics on the fouling behavior on the AEM and changes in the surface and electrochemical properties of the AEM. Results indicated that the fouling degree of the AEM by the different organics followed the order:SDBS > SDS > NSS > BS > MS. SDBS and SDS formed a dense fouling layer on the surface of the AEM, which was the main factor in the much more severe membrane fouling, and completely restricted the transmembrane ion migration. The other three organics caused fouling of the AEM by adsorption on the surface and/or accumulation in the interlayer of the AEM, and exhibited almost no influence on the transmembrane ion migration. It was also concluded that the organics with benzene rings caused more severe fouling of the AEM due to the stronger affinity interaction and steric effect between the organics and the AEM compared with organics with aliphatic chains.