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Laser-induced breakdown spectroscopy (LIBS) is a rapid and simple analytical method that provides qualitative and quantitative elemental information of samples without damaging them and does not require any sample preparation. Recently, an increasing number of studies have used LIBS to detect aerosols. This technique meets the requirements to be used in some practical applications, such as atmospheric monitoring and industrial processes. However, the unique properties of aerosols bring a level of uncertainty to the LIBS signals of the samples, which is an obstacle to overcome. This review attempts to summarize the relevant research regarding aerosol-LIBS, including the various apparatuses, conditional analysis methods, effects of plasma–particle interactions, means for improving signal intensity, and applications. [ABSTRACT FROM AUTHOR]

The high tendency of bio-oil towards polymerization renders bio-oil with the application as the precursor for carbon materials. However, the pathway of the cross-polymerization of the major components of bio-oil was still unclear. Therefore, the cross-polymerization of furfural and the typical carbohydrates (monosaccharides and oligosaccharides) in bio-oil was studied. The results suggested that the cross-polymerization between furfural and sugars existed and proceeded to a significant extent, producing a much higher yield solid polymer than that of single feedstock and the soluble polymers with the varied π-conjugated structure. In addition, the characterization also indicated that the polymerization of furfural was accompanied with the substantial deoxygenation reactions such as dehydration, forming the polymer with a higher carbon content than that from the sugars. Although sugars contain multiple hydroxyl group, the dehydration reactions for elimination of the hydroxyl group did not take place to a remarkable extent during the polymerization, retaining significant hydrogen and oxygen content of polymer. In addition, the cross-polymerization of furfural and the sugars significantly changed the elemental composition, functionalities, thermal stability, and morphologies of the polymer, owing to the varied pathway from the polymerization of the single feedstock. [ABSTRACT FROM AUTHOR]

Using monthly precipitation and monthly mean temperature, a surface humid index was proposed. According to the index, the distributed characteristics of extreme dryness has been fully analyzed. The results indicated that there is an obvious increasing trend of extreme dryness in the central part of northern China and northeastern China in the last 10 years, which shows a high frequency period of extreme dryness; while a low frequency period in the regions during the last 100 years. Compared with variation trend of the temperature in these regions, the region of high frequent extreme dryness is consistent with the warming trend in the same region. [ABSTRACT FROM AUTHOR]

By using ERA-Interim data, the temperature anomaly of the freezing rain and snowstorm event that occurred from 11 to 22 January 2008 in southern China was analyzed. During this period, diabatic heating and temperature advection caused the temperature to increase anomalously over the Tibetan Plateau. The anomalously high temperature moving from the Tibetan Plateau to southern China played several roles. First, the upper-level subtropical jet over China was split into two parts in the north-south direction, which affected the development of freezing rain in southern China; second, a ridge formed because of the warmer air moving to China, which hindered the transport of cold air from its upstream blocking high, forced the cold air to gather behind the ridge, and facilitated the severe cold air outbreak in the later period of the event; third, an inversion layer formed because of the lower-level cold air and upper-level warmer air over southern China, which was conducive to the development of the event over southern China; and finally, because of the temperature anomaly, opposite wind directions appeared at the lower levels (below 700 hPa), which helped transport of warm-moist and cold-dry air to the event area. [ABSTRACT FROM AUTHOR]

The spectral characteristics of precipitation intensity during warm and cold years are compared in six regions of China based on precipitation data at 404 meteorological stations during 1961-2006. In all of the studied regions except North China, with the increasing temperature, a decreasing trend is observed in light precipitation and the number of light precipitation days, while an increasing trend appears in heavy precipitation and the heavy precipitation days. Although changes in precipitation days in North China are similar to the changes in the other five regions, heavy precipitation decreases with the increasing temperature in this region. These results indicate that in most parts of China, the amount of precipitation and number of precipitation days have shifted towards heavy precipitation under the background of a warming climate; however, the responses of precipitation distributions to global warming differ from place to place. The number of light precipitation days decreases in the warm and humid regions of China (Jianghuai region, South China, and Southwest China), while the increasing amplitude of heavy precipitation and the number of heavy precipitation days are greater in the warm and humid regions of China than that in the northern regions (North China, Northwest China, and Northeast China). In addition, changes are much more obvious in winter than in summer, indicating that the changes in the precipitation frequency are more affected by the increasing temperature during winter than summer. The shape and scale parameters of the Γ distribution of daily precipitation at most stations of China have increased under the background of global warming. The scale parameter changes are smaller than the shape parameter changes in all regions except Northwest China. This suggests that daily precipitation shifts toward heavy precipitation in China under the warming climate. The number of extreme precipitation events increases slightly, indicating that changes in the Γ distribution fitting parameters reflect changes in the regional precipitation distribution structure. [ABSTRACT FROM AUTHOR]