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31.
Simultaneous observations for the total column densities of NO2,O3 and H2O were carried on using the portable Spectrometer (438-450 nm and 400-450 nm) and the visible Spectrometer (544.4-628 nm) during premonsoon thunderstorms and embedded hail storm activity at Pune (18°32'N & 73°51'E),India.These observations confirm the fact that there is an increase in O3 and NO2 column densities during thunderstorms.The increase in O3 was observed following onset of thunderstorm,while the increase in NO2 was observed only after the thunder flashes occur.This implies that the production mechanisms for O3 and NO2 in thunderstorm are different.The observed column density of NO,value (1 to 3×1017molecules cm-2) during thunderstorm activity is 10 to 30 times higher than the value (1×10th molecules cm-2) of a normal day total column density.The spectrometric observations and observations of thunder flashes by electric field meter showed that 6.4×1025molecules/flash of NO2 are produced.The increased to-oil column den 相似文献
32.
Gajanan Kapure Chandrakala KariS. Mohan Rao N.D. Rao 《International Journal of Mineral Processing》2007
The Floatex density separator (FDS) is an industrial separator and works on the principle of hindered settling where the settling rate of a particle in suspension is affected by nearby particles. This phenomenon of hindered settling has been described by various authors using the concept of particle slip velocity. The feasibility of one such slip velocity model proposed by Galvin et al. to predict the separation of chromite in a plant scale FDS was examined. Previously this model was validated only at lab scale with synthetic mixture of various density particles. In order to use this model, the feed chromite ore was characterized and quantified into different density mineral classes and their percentages were estimated by using mineralogical grain count method. The performance of FDS was then predicted using slip velocity model in terms of weight recoveries and composition of different minerals in the FDS underflow product. 相似文献
33.
The information on the soundness of rock is very important for enduring safety and stability of miming, marine and civil structures.
The present paper mainly deals with a fuzzy approach to determine the effect of acidic watery environment on the rock strength
of the sandstone rock sample. Fuzzy inference system developed here intelligently predicts the competency of the rock, based
on experimental data used for the model development. The approach used would be able to predict the relative rock strength
at any range of acidic to basic watery environment for any geotechnical investigation or application to achieve long-term
durability. 相似文献
34.
Simultaneous observations of surface ozone (O3) with its precursors namely, carbon monoxide (CO) and oxides of nitrogen (NOx) have been taken on diurnal scale from a tropical semi-urban site, Pune (18.54°N, 73.81°E) in India. We present the data
for one year (2003–2004) period to study the salient features of these trace gases. The peak in amplitude of ozone is found
during the noontime whereas in CO and NOX it is observed in the morning hours between 0800 and 0900 H. The concentration of these pollutants drop down considerably
during southwest monsoon months and the diurnal pattern also become very weak. The diurnal trends of these gases are found
to be different for different seasons, which are specific to the receptor site. Model simulations using 3-D chemical-transport
model with regional emission inventories and observed winds have also been carried out. The comparison of model results with
observations, on seasonal basis yielded a reasonable qualitative agreement. The relative role of local emissions and long
range transport in the diurnal pattern for different seasons has been outlined, which reveals that the ozone is highly influenced
by regional/long range transport in this region. The effect of precursor amounts in the morning on afternoon ozone peak levels
has been investigated using the lag correlation study, which reveals that a time lag of 5–7 h is required for most of these
precursor gases to photo-chemically produce ozone to its maximum potential. Results are discussed in the light of available
topographic and meteorological conditions. 相似文献