Nitrogen oxides(NO_(x))are crucial in tropospheric photochemical ozone(O_(3))production and oxidation capacity.Currently,the widely used NO_(x)measurement technique is chemiluminescence(CL)(CL-NO_(x)),which tends to o...Nitrogen oxides(NO_(x))are crucial in tropospheric photochemical ozone(O_(3))production and oxidation capacity.Currently,the widely used NO_(x)measurement technique is chemiluminescence(CL)(CL-NO_(x)),which tends to overestimate NO_(2)due to atmospheric oxidation products of NO_(x)(i.e.,NO_(z)).We developed and characterized a NO_(x)measurement system using the cavity attenuated phase shift(CAPS)technique(CAPS-NO_(x)),which is free from interferences with nitrogen-containing species.The NO_(x)measured by the CAPS-NO_(x)and CL-NO_(x)analyzers were compared.Results show that both analyzers showed consistent measurement results for NO,but the NO_(2)measured by the CAPS-NO_(x)analyzer(NO_(2)_CAPS)was mostly lower than that measured by the CL-NO_(x)analyzer(NO_(2)_CL),which led to the deviations in O_(3)formation sensitivity regime and O_(x)(=O_(3)+NO_(2))sources(i.e.,regional background and photochemically produced O_(x))determined by the ozone production efficiencies(OPE)calculated from NO_(2)_CL and NO_(2)_CAPS.Overall,OPE_CL exceeded OPE_CAPS by 18.9%,which shifted 3 out of 13 observation days from the VOCs-limited to the transition regime when judging using OPE_CL,as compared to calculations using OPE_CAPS.During the observation period,days dominated by regional background O_(x)accounted for 46%and 62%when determined using NO_(2)_CL and NO_(2)_CAPS,respectively.These findings suggest that the use of the CL-NO_(x)analyzer tends to underestimate both the VOCs-limited regime and the regional background O_(x)dominated days.The newly built CAPS-NO_(x)analyzer here can promote the accurate measurement of NO_(2),which is meaningful for diagnosing O_(3)formation regimes and O_(x)sources.展开更多
提出了利用中国区域定位系统(Chinese Area Positioning System,CAPS)和CAPS终端开展海洋资料浮标通讯和导航的一种新方法。根据海洋资料浮标发送数据量大而接收数据量小的特点,创新性地提出利用复合导航电文的方法,将通信地面站出站发...提出了利用中国区域定位系统(Chinese Area Positioning System,CAPS)和CAPS终端开展海洋资料浮标通讯和导航的一种新方法。根据海洋资料浮标发送数据量大而接收数据量小的特点,创新性地提出利用复合导航电文的方法,将通信地面站出站发送给通信卫星转发改为导航系统下行转发,将CAPS终端通信部分接收改为导航定位部分接收,成功地把CAPS终端发展到CAPS-OC(Chinese Area Positioning System-Ocean Communication,CAPS-OC)终端。海上实验表明CAPS-OC终端及CAPS系统可以满足各种海洋资料浮标的通讯和导航定位的功能要求,目前有两台CAPS-OC终端已经成功地应用在浅海大型锚系浮标观测系统的数据传输中。展开更多
基金supported by the Natural Science Foundation of Guangdong Province(No.2020A1515110526)the Key-Area Research and Development Programof Guangdong Province(No.2020B1111360003)the National Natural Science Foundation of China(No.42305096).
文摘Nitrogen oxides(NO_(x))are crucial in tropospheric photochemical ozone(O_(3))production and oxidation capacity.Currently,the widely used NO_(x)measurement technique is chemiluminescence(CL)(CL-NO_(x)),which tends to overestimate NO_(2)due to atmospheric oxidation products of NO_(x)(i.e.,NO_(z)).We developed and characterized a NO_(x)measurement system using the cavity attenuated phase shift(CAPS)technique(CAPS-NO_(x)),which is free from interferences with nitrogen-containing species.The NO_(x)measured by the CAPS-NO_(x)and CL-NO_(x)analyzers were compared.Results show that both analyzers showed consistent measurement results for NO,but the NO_(2)measured by the CAPS-NO_(x)analyzer(NO_(2)_CAPS)was mostly lower than that measured by the CL-NO_(x)analyzer(NO_(2)_CL),which led to the deviations in O_(3)formation sensitivity regime and O_(x)(=O_(3)+NO_(2))sources(i.e.,regional background and photochemically produced O_(x))determined by the ozone production efficiencies(OPE)calculated from NO_(2)_CL and NO_(2)_CAPS.Overall,OPE_CL exceeded OPE_CAPS by 18.9%,which shifted 3 out of 13 observation days from the VOCs-limited to the transition regime when judging using OPE_CL,as compared to calculations using OPE_CAPS.During the observation period,days dominated by regional background O_(x)accounted for 46%and 62%when determined using NO_(2)_CL and NO_(2)_CAPS,respectively.These findings suggest that the use of the CL-NO_(x)analyzer tends to underestimate both the VOCs-limited regime and the regional background O_(x)dominated days.The newly built CAPS-NO_(x)analyzer here can promote the accurate measurement of NO_(2),which is meaningful for diagnosing O_(3)formation regimes and O_(x)sources.
文摘提出了利用中国区域定位系统(Chinese Area Positioning System,CAPS)和CAPS终端开展海洋资料浮标通讯和导航的一种新方法。根据海洋资料浮标发送数据量大而接收数据量小的特点,创新性地提出利用复合导航电文的方法,将通信地面站出站发送给通信卫星转发改为导航系统下行转发,将CAPS终端通信部分接收改为导航定位部分接收,成功地把CAPS终端发展到CAPS-OC(Chinese Area Positioning System-Ocean Communication,CAPS-OC)终端。海上实验表明CAPS-OC终端及CAPS系统可以满足各种海洋资料浮标的通讯和导航定位的功能要求,目前有两台CAPS-OC终端已经成功地应用在浅海大型锚系浮标观测系统的数据传输中。
