A comparative study of the structure and fractal properties of arrays of the silver nano-/micro-particles deposited on the silicon substrate both from the aerosol and fog showed that the form of the silver individual ...A comparative study of the structure and fractal properties of arrays of the silver nano-/micro-particles deposited on the silicon substrate both from the aerosol and fog showed that the form of the silver individual particles and nano-/microstructures greatly depends on the deposition conditions. By passing an aerosol through isopropyl alcohol, the formation of fractal aggregates of the silver nano-/micro-particles both in the air and in alcohol was observed. Deposition of the silver nano-/micro-particles in the atmosphere of the saturated isopropyl alcohol vapours led to formation of fog. Microdroplets of the silver colloidal solution were deposited on the substrate. The further evaporation of alcohol created the silver nano/microstructures in the form of annular layers. It was found that the concerned annular layers contained silver particles of the same shape in the form of a Crescent (or Janus-nano-/microparticles). The nature of discovered effects is discussed.展开更多
ABSTRACT During a sea-fog field observation campaign on Donghai Island in the spring of 2011, fog-water, visibility, meteorological elements, and fog droplet spectra were measured. The main cations and anions in 191 ...ABSTRACT During a sea-fog field observation campaign on Donghai Island in the spring of 2011, fog-water, visibility, meteorological elements, and fog droplet spectra were measured. The main cations and anions in 191 fog-water samples were Na＋, NH2, H＋, NO3, C1- and SO] , and the average concentrations of cations and anions were 2630 and 2970 p-eq L 1, respectively. The concentrations of Na＋ and C1- originated from the ocean were high. The enhancement of anthropogenic pollution might have contributed to the high concentration of NH＋, H＋, and NO^-3. The average values ofpH and electrical conductivity （EC） were 3.34 and 505 uS cm-1, respectively, with a negative correlation between them. Cold fronts associated with cyclonic circulations promoted the decline of ion loadings. Air masses from coastal areas had the highest ion loadings, contrary to those from the sea. The ranges of wind speed, wind direction and temperature corresponding to the maximum total ion concentration （TIC） were 3.5-4 m s-1, 79°-90° and 21°C-22°C, respectively. In view of the low correlation coefficients, a new parameter Lr was proposed as a predictive parameter for TIC and the correlation coefficient increased to 0.74. Based on aerosol concentrations during the sea-fog cases in 2010, we confirmed that fog-water chemical composition also depended on the species and sizes of aerosol particles. When a dust storm passed through Donghai Island, the number concentration of large aerosol particles （with diameter 〉 1 p-m） increased. This caused the ratio of CaZ＋/Na＋ in fog-water to increase significantly.展开更多
[Objective] The research aimed to review the analysis and research on the physicochemical characteristic observation aspect of fog. [Method] To understand the roles of fog microphysical characteristic and chemical rea...[Objective] The research aimed to review the analysis and research on the physicochemical characteristic observation aspect of fog. [Method] To understand the roles of fog microphysical characteristic and chemical reaction on the formation, dissipation, development of fog, the interaction between the microphysical structure, chemical characteristic of fog and the aerosol in the environment, the analysis and research on the micro-physicochemical observation aspect of fog were mainly introduced here. We also put forward that the field still needed the deep research content. [Result] The observation and research on the micro-physicochemical characteristics of fog could reveal the mechanisms of fog formation, dissipation, development from the microphysical components and the reaction of chemical composition. The previous researches focused on the concentration of micro-fog droplet, the particle size of fog droplet, the liquid water content in the fog, the particle concentration, size, chemical component and reaction of aerosol. It included the evolution and interaction between the microscopic quantities in the fog, the relationship between the microscopic quantity and the visibility. As the improvements of observation experiment instruments and sampling method, it recognized that the fog in the polluted environment condition and the clean air had the obvious difference whether in the microphysical characteristic or the chemical component. The particle concentration, chemical component and liquid water content of fog were all depended on the fog particle size. The interaction between the radiation, turbulent flux and the micro-physical characteristics of fog, the vertical structure of microphysics in the fog, the interaction between the chemical components, the relationship between the microphysical quantity and the macro-physical quantity (such as the visibility), the precision of experimental instrument, etc. needed the further research. [Conclusion] The research provided the comprehensive knowledge for the characteristic analysis and forecast of fog.展开更多
利用2010、2011年在中国广东省湛江市东海岛海雾外场观测试验中获得的观测数据,综合分析海雾发生时的宏微观特征、气溶胶特征和雾水化学特征,并据此探讨海雾形成发展的主要机制。结果表明：南海海雾年平均雾日数为20-30 d,受低压系统或...利用2010、2011年在中国广东省湛江市东海岛海雾外场观测试验中获得的观测数据,综合分析海雾发生时的宏微观特征、气溶胶特征和雾水化学特征,并据此探讨海雾形成发展的主要机制。结果表明：南海海雾年平均雾日数为20-30 d,受低压系统或冷锋过境影响时出现雾的概率最大。2010和2011年平均雾滴液态水含量（Liquid Water Content,LWC）分别为0.019和0.072 g·m^-3,LWC偏低与海陆交界处雾滴湍流沉降加速有关。随着LWC的增加,雾滴与气溶胶数浓度的比值增大。雾水中主要离子为Na^＋和Cl^-,其两年总离子浓度（Total Ion Concentration,TIC）平均值分别为38 260和5 600μeq·L^-1,但离子负荷量相差不大,LWC增加可能是导致2011年TIC下降的主要原因。海雾雾滴形成和发展的主要机制是核化和凝结增长,与陆地和山地雾相比,碰并、湍流和平流因子的影响加强。雾滴谱可用Gamma分布进行拟合,且随着碰并作用增强,滴谱增宽。展开更多
文摘A comparative study of the structure and fractal properties of arrays of the silver nano-/micro-particles deposited on the silicon substrate both from the aerosol and fog showed that the form of the silver individual particles and nano-/microstructures greatly depends on the deposition conditions. By passing an aerosol through isopropyl alcohol, the formation of fractal aggregates of the silver nano-/micro-particles both in the air and in alcohol was observed. Deposition of the silver nano-/micro-particles in the atmosphere of the saturated isopropyl alcohol vapours led to formation of fog. Microdroplets of the silver colloidal solution were deposited on the substrate. The further evaporation of alcohol created the silver nano/microstructures in the form of annular layers. It was found that the concerned annular layers contained silver particles of the same shape in the form of a Crescent (or Janus-nano-/microparticles). The nature of discovered effects is discussed.
基金provided by the Meteorology Fund of the Ministry of Science and Technology [Grant No.GYHY(QX)2007-6-26]the National Natural Science Foundation of China (Grant Nos.41275151 and 41375138)+1 种基金the Priority Academic Program Development of Jiangsu Higher Education Institutionsthe Graduate Student Innovation Plan at the Universities of Jiangsu Province
文摘ABSTRACT During a sea-fog field observation campaign on Donghai Island in the spring of 2011, fog-water, visibility, meteorological elements, and fog droplet spectra were measured. The main cations and anions in 191 fog-water samples were Na＋, NH2, H＋, NO3, C1- and SO] , and the average concentrations of cations and anions were 2630 and 2970 p-eq L 1, respectively. The concentrations of Na＋ and C1- originated from the ocean were high. The enhancement of anthropogenic pollution might have contributed to the high concentration of NH＋, H＋, and NO^-3. The average values ofpH and electrical conductivity （EC） were 3.34 and 505 uS cm-1, respectively, with a negative correlation between them. Cold fronts associated with cyclonic circulations promoted the decline of ion loadings. Air masses from coastal areas had the highest ion loadings, contrary to those from the sea. The ranges of wind speed, wind direction and temperature corresponding to the maximum total ion concentration （TIC） were 3.5-4 m s-1, 79°-90° and 21°C-22°C, respectively. In view of the low correlation coefficients, a new parameter Lr was proposed as a predictive parameter for TIC and the correlation coefficient increased to 0.74. Based on aerosol concentrations during the sea-fog cases in 2010, we confirmed that fog-water chemical composition also depended on the species and sizes of aerosol particles. When a dust storm passed through Donghai Island, the number concentration of large aerosol particles （with diameter 〉 1 p-m） increased. This caused the ratio of CaZ＋/Na＋ in fog-water to increase significantly.
基金Supported by National Natural Science Fund (41075004,41075005)Tianjin Natural Science Fund (08JCYBJC10300)"11th Five-year" National Science and Technology Support Plan Key Item (2008BAC37B01,2008BAC37B05)
文摘[Objective] The research aimed to review the analysis and research on the physicochemical characteristic observation aspect of fog. [Method] To understand the roles of fog microphysical characteristic and chemical reaction on the formation, dissipation, development of fog, the interaction between the microphysical structure, chemical characteristic of fog and the aerosol in the environment, the analysis and research on the micro-physicochemical observation aspect of fog were mainly introduced here. We also put forward that the field still needed the deep research content. [Result] The observation and research on the micro-physicochemical characteristics of fog could reveal the mechanisms of fog formation, dissipation, development from the microphysical components and the reaction of chemical composition. The previous researches focused on the concentration of micro-fog droplet, the particle size of fog droplet, the liquid water content in the fog, the particle concentration, size, chemical component and reaction of aerosol. It included the evolution and interaction between the microscopic quantities in the fog, the relationship between the microscopic quantity and the visibility. As the improvements of observation experiment instruments and sampling method, it recognized that the fog in the polluted environment condition and the clean air had the obvious difference whether in the microphysical characteristic or the chemical component. The particle concentration, chemical component and liquid water content of fog were all depended on the fog particle size. The interaction between the radiation, turbulent flux and the micro-physical characteristics of fog, the vertical structure of microphysics in the fog, the interaction between the chemical components, the relationship between the microphysical quantity and the macro-physical quantity (such as the visibility), the precision of experimental instrument, etc. needed the further research. [Conclusion] The research provided the comprehensive knowledge for the characteristic analysis and forecast of fog.
文摘利用2010、2011年在中国广东省湛江市东海岛海雾外场观测试验中获得的观测数据,综合分析海雾发生时的宏微观特征、气溶胶特征和雾水化学特征,并据此探讨海雾形成发展的主要机制。结果表明：南海海雾年平均雾日数为20-30 d,受低压系统或冷锋过境影响时出现雾的概率最大。2010和2011年平均雾滴液态水含量（Liquid Water Content,LWC）分别为0.019和0.072 g·m^-3,LWC偏低与海陆交界处雾滴湍流沉降加速有关。随着LWC的增加,雾滴与气溶胶数浓度的比值增大。雾水中主要离子为Na^＋和Cl^-,其两年总离子浓度（Total Ion Concentration,TIC）平均值分别为38 260和5 600μeq·L^-1,但离子负荷量相差不大,LWC增加可能是导致2011年TIC下降的主要原因。海雾雾滴形成和发展的主要机制是核化和凝结增长,与陆地和山地雾相比,碰并、湍流和平流因子的影响加强。雾滴谱可用Gamma分布进行拟合,且随着碰并作用增强,滴谱增宽。
