国产傅立叶变换红外光谱温室气体在线监测仪及其在大气本底监测中的初步应用

大气温室气体的监测,是掌握温室气体浓度时空变化特征及其影响因素依据。而大气本底监测反映了较大范围内,因人类活动而造成的大气成份长期变化,是温室气体监测的基础数据。大气本底站附近温室气体浓度相对较低,年变化范围小,从而对温室气体连续监测技术精度与稳定性提出了更高的要求。本文基于傅立叶红外技术与WHITE型多次反射池技术方法,研究大气本底温室气体CO2、CH4、N2O超低浓度检测系统。针对CO2、CH4、N2O的分子吸收光谱特征,采用碳化硅作为光源,将测量波段选择在1900-2600区间;采用模拟仿真,模拟不同透过系数和多种气体混合干扰状态下的仪器理论测量精度,根据验证结果,傅里叶红外仪器在CO2、CH4、N2O测量方面表现良好,满足超低浓度温室气体的监测需求。     

基于MOPITT数据的北京奥运前后CO监测分析

利用MOPITT卫星资料及近地面监测数据,研究了奥运前后北京大气CO柱浓度及近地面质量浓度的分布及变化规律.发现: CO柱浓度反映了区域大气污染水平,而其近地面质量浓度主要受局地污染源排放的影响.大陆背景点瓦里关站CO柱浓度与近地面质量浓度季节变化较为相似,都以春季最高;而北京CO柱浓度与近地面质量浓度季节变化差异较大,CO柱浓度以春季最高,而近地面质量浓度采暖期明显高于非采暖期.2000～2007年8月北京大气CO柱浓度缓慢升高,而其近地面质量浓度呈显著下降趋势.2008年受奥运空气质量保障措施的影响,北京及周边五省市CO排放显著减少,大气中CO柱浓度及近地面质量浓度同时大幅度降低.北京CO柱浓度下降19.3%,而近地面浓度更是下降了46.7%.后者降幅更大,主要源于北京较周边省市采取了更大力度的空气质量保障措施.空气质量保障措施极大地减少了CO的总量排放,但未改变区域大气污染分布格局.     

基于短波红外波段吸收的CO2垂直柱浓度地基遥测反演方法研究

温室气体引起的全球变暖、气候变化等问题已成为国际关注的热点,其中CO2是重要的温室气体之一,CO2的监测与控制已经成为各国关注的重点。结合CO2在1.6 μm处的光谱吸收结构,利用加权函数修正的差分吸收光谱技术（weighted function modified difference absorption spectroscopy, WFM-DOAS）研究大气中CO2垂直柱浓度的反演方法。利用大气辐射传输模型仿真研究了不同参数对加权函数（weighted function, WF）计算灵敏度的影响,分别对观测高度、太阳天顶角、太阳方位角、地表反照率、光谱分辨率等参数对CO2 WF系数的影响进行了详细的计算分析。并以一整天测量的太阳光为例,对仪器的性能、CO2的垂直柱浓度及干扰气体CH4及H2O的垂直柱浓度进行了分析,初步分析得到的反演误差优于1%。     

基于卫星遥感的中国地区XCO2 和XCH4 时空分布研究

人为活动排放的以CO2 和CH4 为主的大量温室气体是造成全球增温的主要因素。由于地面观测站点稀少, 卫星遥感为监测CO2 和CH4 的时空分布及变化趋势提供了新的技术手段。本文验证了GOSAT、OCO-2 卫星的大气 CO2 和CH4 柱浓度遥感产品XCO2 和XCH4 的精度, 并分析了我国XCO2 和XCH4 的时空分布和变化趋势, 主要结论 如下: (1) 在所用XCO2 遥感产品中, OCO-2 ACOS 与地面观测的相关性最高(达0.93); 而XCH4 产品中GOSAT OCPR 的相关性最高(达0.78)。(2) 在研究的时间跨度内, XCO2 浓度呈逐年上升趋势, 如我国OCO-2 XCO2 年均浓度由2014 年的396.92 × 10−6 增长到2021 年的414.72 × 10−6; CO2 浓度高值主要分布在城市和工业集中的中国东部地区, 西北 地区塔克拉玛干沙漠的高值与气溶胶散射影响有关; 同时, 受人为源和自然源的季节变化影响, XCO2 具有冬春高、夏 秋低的时间特征。(3) XCH4 浓度同样呈逐年上升趋势, 但与XCO2 不同, XCH4 浓度高值主要分布在天然气和煤炭开 采集中的四川东部、重庆西部、陕西与山西的中部地区, 以及工业集中的华北地区, 季浓度呈现夏秋高、春冬低的特 征。(4) 2020 年XCO2 高值区发生偏移; 相对于2020 年, 2021 年CO2 增速有所回升, 但增幅相对于2019 年之前仍有 所减小。     

大尺度区域CO_2和H_2O的激光在线检测技术

CO2和H2O是大气中两种重要的温室气体,对生态系统中CO2和H2O的浓度进行在线监测可用于分析环境及气候变化。选择CO2和H2O的近红外吸收谱线,利用可调谐半导体激光吸收光谱技术结合自动增益调节技术设计了开放式CO2和H2O在线检测仪。在中国科学院禹城综合试验站进行了1238m光程下,20Hz时间分辨率的连续观测实验,结果表明自动增益调节解决了开放光路检测时探测信号幅度大幅变化问题。监测点的CO2浓度具有白天低,夜间高的日变化周期性。与同场地涡度相关系统的LI-7500对比测量,数据一致性较好。该检测技术灵敏度高、响应速度快、免采样,实现了大尺度区域生态系统中CO2和H2O浓度的稳定、连续、在线检测。     

X-Fest:技术分销的微观样本

日前,安富利电子元件与赛灵思公司举办的X-Fest2010系列研讨会深圳站正式开幕,该研讨会自去年10月启动,计划在全球37个城市举办,亚洲地区为11个城市,覆盖中国大陆、中国台湾、韩国、新     

傅里叶红外系统监测大气中温室气体的污染特征

研制了一套90 m的开放光路傅里叶变换红外光谱(OP-FTIR)温室气体分析测量设备，并利用该设备开展了CO₂、CH₄和CO质量浓度的高精度检测。OP-FTIR系统反演CO₂、CH₄和CO的光谱区域分别为2102～2250 cm^-1、2920～3140 cm^-1和2172～2210 cm^-1。以采集到的中红外吸收光谱为反演基准，开展了与Picarro温室气体分析仪的对比测试。选取测量期间10 d的数据，研究了温湿度、风向风速与环境大气中CO₂、CH₄和CO质量浓度的关联度，并详细分析了污染物的日变化特征。实验结果表明：研制的OP-FTIR光谱系统监测温室气体质量浓度具有较高的可靠性；温度、相对湿度、风速和风向对当地污染物质量浓度影响显著；CO₂、CH₄和CO质量浓度的时序变化具有明显的周期性变化趋势。将CO、CH₄质量浓度分别...     

基于主成分分析的CO2统计反演方法

二氧化碳（CO2）卫星遥感中,大气环境因素是影响反演精度的重要原因,目前反演条件通常限制在气溶胶光学厚度小于0.3的情况。我国大气气溶胶高值情况较为普遍,对大气条件的较高要求将严重影响我国CO2卫星遥感数据的应用能力。针对这种情况,利用基于主成分分析法对中国京津地区高气溶胶光学厚度的大气CO2反演,得到的CO2柱浓度与2013年、2014年GOSAT-Level2产品进行对比分析,均方根误差分别为0.65%和0.46%,相关性分别为0.77和0.93。     

基于GOSAT-2卫星的中国XCO2 时空分布特征分析

CO₂是主要的温室气体之一,它对全球变暖的作用很大。自工业化以来,CO₂浓度在全球范围内大幅增加。为实现碳减排目标,迫切需要监测大气中的CO₂浓度并分析其时空分布特征。随着温室气体观测卫星的发射,利用碳卫星可以大范围地观测和分析大气中的CO₂浓度。本研究基于GOSAT-2卫星数据,利用克里金插值技术分析了2020年6月至2021年5月中国陆地区域的CO₂柱浓度(XCO₂)的时空变化特征。结果表明,全国范围内XCO₂的平均值从2020年的413.86 ppm增加到2021年的419.59 ppm,增加了5.73 ppm。其中,XCO₂的最低值和最高值分别出现在冬季和春季。进一步的分析表明,XCO₂在空间分布上不一致,在人口密度较高的东南部区域浓度较高,而在人口稀少的西北部较低。此外,大城市及其周边地区的XCO₂普遍高于其他地区,表明人为因素导致城市地区的XCO_2...     

温室气体及碳同位素比值傅里叶变换红外光谱分析的温度依赖关系研究

为了研究温度变化对温室气体及碳同位素比值光谱定量分析的影响,首先从理论上分析得出温室气体浓度及13CO2值的定量反演主要取决于吸收系数,并研究了吸收系数的计算方法.其次结合HITRAN数据库,研究了温度对线强、展宽以及吸收系数的影响规律,结果表明:压强为1 atm(1 atm=1.013105 Pa)恒定条件下,温度变化时,吸收系数受线强变化的影响强于受展宽变化的影响.最后通过实验验证了温室气体和碳同位素比值傅里叶变换红外光谱(FTIR)反演的温度依赖关系,其中碳同位素比值受温度变化影响幅度最大,单位温度变化对13CO2值的影响为14.37.文中结果为高精度温室气体及碳同位素比值红外光谱监测装置中的温度监控系统设计提供了理论依据.     

Unity of objective, diversity of approach: deregulatory telecomdevelopments in Hong Kong and China

Asia-Pacific policy makers in Singapore, Taiwan, Korea, and Malaysia are “benchmarking” their “deregulatory” progress with that of Hong Kong. In contrast to Hong Kong's “fast-track” deregulatory approach, China has been more conservative. This article analyzes the impact of telecommunications (de)regulatory policies on broadband infrastructure investment in Hong Kong and China, respectively     

Poised for technological leadership

Technological advances in the East Asian nations of Japan, South Korea, Taiwan, Hong Kong, and Singapore are surveyed, focusing on how they are striving to adjust their strategies to a changing market and looking to new technologies to give them competitive edges. In addition to consumer electronics, microelectronics, and computers, where they already have an established lead, the areas of automotive electronics, manufacturing automation, telecommunications, aerospace and military, medical electronics, power and energy, and transportation are examined     

East Asia's power crescent

The economic and technological advances of Japan, South Korea, Taiwan, Hong Kong, and Singapore are examined, focusing on how these advances have been achieved, how they have affected these countries and their Asian neighbors, and how they might further reconfigure the region's economic and technological profiles. The economic and technological status of three other nations, which are trailing behind but are alluring enough to industries and investors to have reached development's first rung, is briefly discussed. The problems posed by the poverty and political instability of the region, as well as by regional rivalries, are considered. Predictions for the future of the region are offered     

MBE: 8th international conference on molecular beam epitaxy,Osaka, Japan

MBE-VIII was held at the Senri Life Centre, Osaka, Japan from August 29 to September 2, the Chairman was Prof. Shun-ichi Gonda of Osaka University. The meeting was very well attended with over 450 delegates coming from as far as North America (44) and Europe (75) and, of course, a large contingent of our Japanese friends (310). Countries like China, Taiwan, Korea and Hong Kong were also represented. There were 16 invited papers and well over 100 and 160 oral presentations and posters, respectively. As might be expected, Japan provided the majority of contribution with approximately half the papers. The UK was also well represented with 20 papers. The conference also attracted some 17 commercial exhibits and supported by 25 sponsors. These statistics were taken from the registration list and conference proceedings.     

亚太地区主要国家RFID应用的发展特点

目前在亚太地区,特别重视RFID应用的国家和地区有美国、日本、中国、新加坡、中国台湾和中国香港等。本文在研究、分析美国、日本和中国在应用RFID的不同特点的基础上,得出中国在RFID的应用上应该侧重于哪些方面的结论。     

Malaysia: an Asian gateway to the world

Apart from China with its enormous human resources, we talk of the “Four Tigers”, South Korea, Taiwan, Hong Kong and Singapore. But others are following in their footsteps in that the market economy in its various forms is being accepted as the guiding economic principle in countries like Malaysia. Malaysia is strategically located in the heart of Southeast Asia -one of the world's fastest growing regions. Today, Malaysia is amongst the world's leading exporters of manufactured goods, such as semiconductors and audio-visual equipment. I was greatly impressed with the economic strides taking place in Malaysia which is also becoming the Asian base for semiconductors.     

欧盟科研和国际热核聚变实验堆（ITER）计划中的科学传播政策

本文首先回顾了欧盟在跨国合作项目研究中所实施的科学传播政策,并进一步呈现了由中国、欧盟、印度、日本、韩国、俄罗斯以及美国共同参与的国际热核聚变实验反应堆计划中所构建的科学传播战略以及开展的活动。     

Formula for competitiveness [electronics]

Approaches taken by the countries of Asia's Pacific rim to competing successfully in the electronics marketplace are examined. Key elements are strong government support, national technical objectives, dynamic science and technology centers, and robust educational institutions. National teamwork in Japan, South Korea, Taiwan, Hong Kong, and Singapore is discussed. The activities of Japan's Ministry of International Trade and Industry (MITI), which is well known for its role in shaping the country's business environment, and its clones are described. The explosion of science parks and research centers throughout Asia is discussed. The East Asia approach to education is considered, focusing on science and technology     

Concentration and Homogenization of International Movie Sources: Examining Foreign Film Import Profiles

This study examines the source diversity of the global film trade by assessing the profiles of individual countries' imported films. Theatrical movie imports to 94 countries from 1970 to 1999, sorted by production origin (i.e., USA, Italy, France, U.K., India, Russia, Germany, Japan, Hong Kong, and others), are tested, using United Nations Educational, Scientific, and Cultural Organization data, against hypotheses of centralization and homogenization among these major import sources. An empirical model is devised to quantify and explain such situations and their trends over the country panel. Regressions show that the interexporter share concentration of film imports within countries increased significantly over the period of study and that this trend is mediated by language, economic, and regional variables. It is further shown that the changes of the global shares of different exporters are dependent on their relative positions. Dominant exporters' shares escalated but those of the small counterparts dropped over time. The importers' source profiles had become more alike, as indicated by the statistics.