大气气溶胶研究现状和发展趋势

对国际大气气溶胶研究现状及主要研究成果进行了分析总结,讨论了未来气溶胶研究的主要领域,着重讨论了气溶胶对气候和环境影响的主要问题。就沙尘气溶胶和人为活动造成的气溶胶两个方面讨论当前急需研究解决的问题。     

气溶胶灭火剂的研究进展

作为一种环保型高效的灭火剂,气溶胶灭火剂越来越受到世界各国科研人员的重视,特别是近30年来人们对其进行了较为深入的研究和应用开发.综述了气溶胶灭火剂的类型、灭火机理、使用效果以及当今气溶胶灭火剂的主要研究方向,分析了最新气溶胶灭火产品的性能和原理,并展望了气溶胶灭火剂的发展前景.     

气溶胶吸湿特性研究现状

综述近30年来国内外对气溶胶吸湿性研究的实验方法和研究结果,并分析影响气溶胶吸湿性的各种内在和外在因素,介绍加湿串联差分迁移分析仪(H-TDMA)在过去的25年研究中被广泛用来进行细粒子在不同相对湿度下的吸湿特性试验。通过试验发现:不同成分气溶胶吸湿生长情况不同;无机水溶性气溶胶一般具有较强的吸湿性,而有机组分对气溶胶吸湿性的影响有较大差异。在大气环境测量中,发现来自生物质燃烧的气溶胶在相对湿度大于80%时出现单峰及双峰,在城市区域观察到多峰现象,这说明由于混合状态不同以及组分不同将导致气溶胶吸湿长大行为的变化。     

熔喷聚丙烯驻极体空气过滤材料对不同气溶胶的过滤性能及过滤机理研究

测定了熔喷聚丙烯驻极体空气过滤材料对离子型(KCl)、极性非离子型(DEHS)两种不同实验气溶胶粒子的过滤性能,研究了粒子的粒径、荷电特性及流动速率对过滤性能的影响,分析了惯性效应、扩散效应和静电效应对粒子捕获能力的贡献。结果表明,熔喷聚丙烯驻极体空气过滤材料对不同气溶胶粒子的捕获能力差别较大,对KCl气溶胶的捕获能力要优于DEHS气溶胶,其原因与驻极体空气过滤材料所具有的特殊的静电效应有关。KCl用作实验气溶胶时,不出现MPPS(最易透过粒径)现象,过滤机理以静电效应为主;DEHS用作实验气溶胶时,MPPS值在0.08μm附近,小于经典单纤维过滤值0.3μm,过滤机理以惯性效应、扩散效应为主,以静电效应为辅。     

中国夏季硫酸盐气溶胶间接辐射强迫的数值模拟

运用发展的区域系统集成模式RIEMS,结合Slingo参数化方案,研究了中国夏季硫酸盐气溶胶对云特性(云滴有效半径)的影响及其所产生的间接辐射效应。模拟的云滴尺度分布基本合理,数值在0～10μm之间,但与卫星数据MODIS相比偏小。硫酸盐气溶胶间接辐射强迫7月平均值为-2.58W/m2,空间变化在-10～-1W/m2之间,最大值出现在东北长白山地区,陆地上的负强迫大于海洋。间接辐射强迫与气溶胶浓度分布和云水分布有密切的关系。     

大气气溶胶对混合相对流云影响的模拟研究

利用二维面对称分档云模式,讨论了气溶胶类型及浓度对混合相对流云及其降水的影响。结果表明:海洋性气溶胶谱分布在一定程度上更有利于降水的形成,随着气溶胶浓度的增加,尤其是在污染大陆性云中,暖云和冷云降水量均大幅减少。海洋性云中的大粒子和较高的过饱和度,加速了暖雨的碰撞过程和冰粒子的凝华增长;初始气溶胶浓度的增加最显著的效应是云滴数浓度和云水含量增加,云滴有效半径减小,云滴的冷却蒸发抑制对流的发展。     

放射性气溶胶净化的研究进展

人工核素应用的快速增长产生的大量放射性气溶胶颗粒日益危害环境及人体的健康。本文中综述了放射性气溶胶的特性,根据国内外文献报道,分析了放射性气溶胶的监测方法、净化技术的研究现状以及影响放射性气溶胶净化的主要因素,提出了目前放射性气溶胶净化存在的问题,并指出结合放射性气溶胶的特性采取与之合适的凝并技术是今后放射性气溶胶净化的主要研究方向。     

气溶胶光学厚度的双角度多光谱反演方法研究

给出了利用角度和光谱两方面信息进行气溶胶光学厚度反演的方法,依据反演方法要求研制了机载双角度多光谱大气辐射计,并通过航空模拟实验验证了用其进行空间对地气溶胶光学厚度反演的可行性。实验结果显示,利用双角度和多光谱的方法,可以摆脱传统方法对地面反射率数据的依赖,在一般区域能够实现实时空间对地气溶胶光学厚度的反演,从而显示出了该方法在对卫里光学遥感数据校正和研究全球气溶胶对气候影响上的潜力。     

气溶胶光度计质量浓度校准设备及方法研究

本研究设计开发了气溶胶光度计质量浓度校准设备,并对其在气溶胶光度计校准过程中的适用性进行了验证。实验结果表明,本研究设计的气溶胶发雾混匀装置具有良好的发雾稳定性,在高浓度和低浓度发雾测试中其稳定性均在5%以内,气溶胶浓度相对标准偏差小于2%。称重法校准结果表明,精密气溶胶光度计在全量程范围内的示值误差均低于5%,具有较高的准确度,可用于气溶胶光度计的校准。最后进行了比对校准,实验结果表明本设备在气溶胶光度计校准过程中具有良好的适用性,可满足校准溯源工作的需求,对于提高气溶胶光度计检测结果的可靠性具有重要意义。     

气溶胶静电计的校准技术研究及方法优化

<正>本文通过对气溶胶静电计(FCAE)校准技术进行研究,并对校准方法进行优化,以满足FCAE校准及对气溶胶数量浓度准确测量的需求。一、气溶胶静电计的原理及组成气溶胶静电计(FCAE)是国际公认的颗粒计数(数量浓度)最高标准,测量结果可溯源至电流。其工作原理为:当带有单一电荷的颗粒气溶胶进入FCAE的采样入口后,颗粒被截留在放置于法拉第杯中的高效过滤器上,此时由于空间电荷效应,颗粒携带的电荷会     

Recent developments in aerosol measurement techniques and the metrological issues

A small error in the aerosol measurements can lead to a considerable influence on our understanding towards its impact on climate. To better simulate aerosol effects on the earth’s radiation budget, the chemical and physical characterizations of aerosol particles with accurate measurements have been a key interest in the aerosol research for last several decades. Recent advances in the chemical characterization of aerosols at bulk and molecular levels, and their physical characterization, such as size distribution, hygroscopicity, and cloud condensation nuclei (CCN) activity have improved our knowledge to better understand the aerosol sources, concentration distributions, atmospheric processing and their potential climate impacts. Apart from the complexity of atmospheric aerosols, because of the limited availability of aerosol certified reference materials, traceability data and measurement protocols, it is still a challenging task to measure the aerosol properties with reduced uncertainty. The recent developments on aerosol analytical techniques (on-line and off-line), which include gas chromatography/flame ionization detector (GC/FID)/mass spectrometry (MS)/isotope ratio mass spectrometry (irMS), ion chromatography (IC), organic carbon/elemental carbon (OC/EC) and water-soluble organic carbon (WSOC) analyzers, and physical measurements using scanning mobility particle sizer (SMPS), hygroscopicity tandem differential mobility analyzer (HTDMA) and cloud condensation nuclei-counter (CCN-C) are discussed with the metrological issues in the measurements. The importance of aerosol metrology is highlighted giving the data obtained from the laboratory studies and aerosol field campaigns.     

Growing trend of China’s contribution to tissue engineering

This study examines China’s performance on tissue engineering using scientometrics measures such as China’s global publication share, rank, growth rate and citation impact, its publications in various sub-fields, top journals in terms of national share based on last 5 years (2008–2012) publications data obtained from ISI Science citation index expanded database. We have also determined Chinese share with international collaborative papers at the national level, as well as h-core papers and high-cited papers, etc.     

国内幸福感设计的研究文献评述及问题分析

目的 就国内幸福感和幸福感设计的相关研究论文展开分析和总结。方法 采用文献分析法,以近十年来国内已发表的相关论文为分析依据。结论 对比幸福感研究,国内幸福感设计的研究成果很少,理论价值不高。本文倡导树立积极、正向的设计价值观,倡导为幸福设计的价值取向;期待从研究理论及方法上对此领域展开更为科学、深入和广泛的探究。     

Discovering interdisciplinary interactions between two research fields using citation networks

This bibliometric analysis focuses on the general history of climate change research and, more specifically, on the discovery of the greenhouse effect. First, the Reference Publication Year Spectroscopy (RPYS) is applied to a large publication set on climate change of 222,060 papers published between 1980 and 2014. The references cited therein were extracted and analyzed with regard to publications, which are cited most frequently. Second, a new method for establishing a more subject-specific publication set for applying RPYS (based on the co-citations of a marker reference) is proposed (RPYS-CO). The RPYS of the climate change literature focuses on the history of climate change research in total. We identified 35 highly-cited publications across all disciplines, which include fundamental early scientific works of the nineteenth century (with a weak connection to climate change) and some cornerstones of science with a stronger connection to climate change. By using the Arrhenius (Philos Mag J Sci Ser 5(41):237–276, 1896) paper as a RPYS-CO marker paper, we selected only publications specifically discussing the discovery of the greenhouse effect and the role of carbon dioxide. Using different RPYS approaches in this study, we were able to identify the complete range of works of the celebrated icons as well as many less known works relevant for the history of climate change research. The analyses confirmed the potential of the RPYS method for historical studies: Seminal papers are detected on the basis of the references cited by the overall community without any further assumptions.     

Assessment of world aerosol research trends by bibliometric analysis

This study was to explore a bibliometric approach to quantitatively assessing current research trends on atmospheric aerosol, using the related literature in the Science Citation Index (SCI) database from 1991 to 2006. Articles were concentrated on the analysis by scientific output, research performances by individuals, institutes and countries, and trends by the frequency of keywords used. Over the years, there had been a notably growth trend in research outputs, along with more participation and collaboration of institutes and countries. Research collaborative papers shifted from national inter-institutional to international collaboration. The decreasing share of world total and independent articles by the seven major industrialized countries (G7) was examined. Aerosol research in environmental and chemical related fields other than in medical fields was the mainstream of current years. Finally, author keywords, words in title and keywords plus were analyzed contrastively, with research trends and recent hotspots provided.     

Characteristics of research in China assessed with Essential Science Indicators

To provide an overview of the characteristics of research in China, a bibliometric evaluation of highly cited papers with high-level representation was conducted during the period from 1999 to 2009 based on the Essential Science Indicators (ESI) database. A comprehensive assessment covered overall performance, journals, subject categories, internationally collaborative countries, national inter-institutionally collaborative institutions, and most-cited papers in 22 scientific fields. China saw a strong growth in scientific publications in the last decade, to some extent due to increasing research and development expenditure. China has been more active in ESI fields of chemistry and physics, but more excellent in materials science, engineering and mathematics. Most publications were concerned with the common Science Citation Index subject categories of multidisciplinary chemistry, multidisciplinary materials and science, and physical chemistry. About one half China’s ESC papers were internationally collaborative and the eight major industrialized countries (the USA, Germany, the UK, Japan, France, Canada, Russia, and Italy) played a prominent role in scientific collaboration with China, especially the USA. The Chinese Academy of Sciences took the leading position of institutions with many branches. The “985 Project” stimulated the most productive institutions for academic research with a huge funding injection and the universities in Hong Kong showed good scientific performance. The citation impact of internationally collaborative papers differed among fields and international collaborations made positive contributions to academic research in China.     

International collaboration in science: Participation by the Asian giants

Science in the last few years has become increasingly global and collaborative. The number of internationally coauthored papers has been increasing steadily. We have counted internationally jointly authored papers involving authors from the advanced countries and the Third World countries, usingSCI 1991. We have looked at the number of papers resulting from collaboration among authors residing in the countries of the North (e.g. EC and OECD countries), authors residing in the South (e.g. India and Bangladesh, Mexico and Brazil, China and Pakistan) and papers resulting from collaboration between authors residing in the countries of the South and the North (e.g. India and UK, China and USA). Despite its late start, China has published many more collaborative papers with most Asian countries and the advanced countries of the West except the UK than India — confirming the effectiveness of the open door policy of post-Mao China. Both India and China collaborate with USA much more often in physics than in other areas, followed by clinical medicine. However, India collaborates more with USA in chemistry than China. In Indo-US and Sino-US collaborations, collaborating institutions are mostly universities and institutes of higher learning in India and USA, whereas in China several institutions under the Academies also take part. The percentage of collaborative papers involving authors from India is even smaller than the percentage of journal articles originating from India. In general, papers resulting from international collaboration appear in better journals and are cited more often than papers that are the outcome of local research.Paper presented at the Fourth International Conference on Bibliometrics, Informetrics and Scientometrics in Berlin (Germany), September 11–15, 1993.     

A comparative study of research performance in computer science

The paper compares the research performance in computer science of four major Western countries, India and China, based on the data abstracted from INSPEC database during the period 1993–2002. A total of 9,632 computer science papers recorded in INSPEC database were used for the comparison. The findings indicate that, on the one hand, the number of papers produced in China has considerably increased in the past few years. Particularly, in recent years, China occupies a remarkable high position in terms of counts of papers indexed by the INSPEC database. On the other hand, Chinese scientists preferred to publish in domestic journals and proceedings and shares of SCI-papers to the total journal papers for China have still remained the lowest. This indicates that the research activities of Chinese scientists in computer science are still rather “local” and suffer from a low international visibility. Various scientometric indicators, such as Normalized Impact Factor, ratio of papers in high quality journals are further adopted to analyze research performance and diverse finding are obtained. Nevertheless, for these surrogate indicators, China has optimistically achieved great progress, characterized with “low level of beginning and high speed of developing”. The policy implication of the findings lies in that China, as well as other less developed countries in science, can earn relative competitive advantages in some new emerging or younger disciplines such as computer science by properly using catch-up strategy. This revised version was published online in June 2006 with corrections to the Cover Date.     

Difference in the impact of open-access papers published by China and the USA

We analyze the impact of open-access (OA) articles published by China and the USA by using Web of Science (WoS) data covering a period of 5 years (2011–2015), five indexes (citation and four altmetric indexes), five disciplines, and three types of articles. With regard to article type, Type I papers are those wherein the authors are all from China or the USA. Type II are those in which the first author is from China or the USA. Type III includes those in which the first author is not from China or the USA. We found that the proportion of OA papers in WoS has been growing in recent years. In terms of citations and altmetric indexes, the mean value of the USA is larger than that of China in general; Type II articles possess the highest value among all papers in the USA, whereas Type III has the highest value in China. Compared with the scenario in citations, social sciences and humanities possess larger altmetric values in China and the USA. The correlation among indicators is similar for the OA papers from China and the USA. Generally, citations cannot effectively represent the altmetric indexes. The gap between China and the USA is the largest in the altmetric attention score and Type I, and the smallest in citations and Type III. Measuring the international impact of OA papers using only citations underestimates the gap between China and the USA.