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排序方式: 共有172条查询结果,搜索用时 15 毫秒
1.
K. Niranjan V. Sreekanth B. L. Madhavan T. Anjana Devi B. Spandana 《Journal of Earth System Science》2008,117(1):421-427
Realizing the importance of aerosol physical properties at the adjoining continental and coastal locations in the airmass pathways onto the oceanic region, extensive measurements of aerosol physical properties were made at Visakhapatnam (17.7°N, 83.3°E), an eastern coastal location in peninsular India during the ICARB period. The temporal variations of aerosol optical depth, near surface aerosol mass size distributions and BC mass concentrations show significantly higher aerosol optical depth and near surface mass concentrations during the first and last weeks of April 2007. The mean BC mass fraction in the fine mode aerosol was around 11%. The aerosol back scatter profiles derived from Micro Pulse Lidar indicate a clear airmass subsidence on the days with higher aerosol optical depths and near surface mass fraction. A comparison of the temporal variation of the aerosol properties at Visakhapatnam with the MODIS derived aerosol optical depth along the cruise locations indicates a resemblance in the temporal variation suggesting that the aerosol transport from the eastern coastal regions of peninsular India could significantly affect the aerosol optical properties at the near coastal oceanic regions and that the affect significantly reduced at the farther regions. 相似文献
2.
A model of solar flare is proposed, taking into account the high temperature (109K) produced by the shock wave generated by the hydromagnetic wave at the junction of sunspot and the area just outside it and subsequent explosive hydrogen burning, producing the desired 1028–29 ergs of a solar flare. 相似文献
3.
The solution of two-dimensional problem of an interface breaking long inclined dip-slip fault in two welded half-spaces is
well known. The purpose of this note is to obtain the corresponding solution for a blind fault. The solution is valid for
arbitrary values of the fault-depth and the dip angle. Graphs showing the variation of the displacement field with the distance
from the fault, for different values of fault depth and dip angle are presented. Contour maps showing the stress field around
a long dip-slip fault are also obtained 相似文献
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B. Kiran K. Pathak R. Kumar D. Deshmukh N. Rani 《International Journal of Environmental Science and Technology》2016,13(7):1823-1832
Microalgal lipids can be enhanced through varying nitrogen (N) content, and limited supply of nitrogen source seems to be valuable approach for increased lipid accumulation in microalgae. In this study, Chlorella sp. IM-02 was observed under fluorescence microscope for increased number of lipid bodies under nitrogen scarcity. Fourier transform infrared spectroscopy was used to determine spectral changes due to varying lipid content under nitrogen-starved (N0, without sodium nitrate), nitrogen-limited (N0.1, N0.25, N0.5 and N1.0 representing 0.1, 0.25, 0.5 and 1.0 g/L of sodium nitrate, respectively) and nitrogen-sufficient (N1.5, i.e., 1.5 g/L sodium nitrate) setting. Chlorophyll content was also monitored under these conditions as growth indicator. Various biochemical components viz. total carbohydrates, total proteins and total lipids were also estimated under varying nitrogen levels spectrophotometrically. On fourth day itself, maximum lipid productivity was observed in case of N0.5, which is having one-third of nitrogen concentration present in original growth media, BG-11. This concludes N0.5 as suitable nitrogen provision for better production of lipids in Chlorella sp. IM-02 without much compromising the biomass production as both growth and lipid quantity are key parameters affecting the lipid productivity of any microalgal strain. 相似文献
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Satya Prakash Sahu Manish Yadav Dhruti Sundar Pradhan Neha Rani Arka Jyoti Das 《Arabian Journal of Geosciences》2018,11(10):241
The objective of the study is to investigate spatio-temporal variations of PM10, PM2.5, and PM1 concentrations at seven residential sites, located in the vicinity of opencast coal projects, Basundhara Garjanbahal Area (BGA), India. Meteorological parameters such as wind speed, wind direction, relative humidity, and temperature were collected simultaneously with PM concentrations. Mean concentrations of PM10 in the range 215 ± 169–526 ± 412 μg m?3, PM2.5 in the range of 91 ± 79–297 ± 107 μg m?3, PM1 in the range of 68 ± 60–247 ± 84 μg m?3 were obtained. Coarse fractions (PM2.5–10) varied from 27 to 58% whereas fine fractions (PM1–2.5 and PM1) varied in the range of 51–73%. PM2.5 concentration was 41–74% of PM10 concentration, PM1 concentration was 31–62% of PM10 concentration, and PM1 concentration was 73–83% of PM2.5 concentration. Role of meteorology on PM concentrations was assessed using correlation analysis. Linear relationships were established among PM concentrations using least square regression analysis. With the aid of principal component analysis, two components were drawn out of eight variables, which represent more than 75% of variance. The results indicated that major sources of air pollutants (PM10, PM2.5, PM1, CO, CO2) at the residential sites are road dust raised by vehicular movement, spillage of coal generated during transportation, spontaneous combustion of coal, and biomass burning in village area. 相似文献
10.
Sudhir Kumar Tewatia Pratima Rani Bose Asuri Sridharan Sunanda Rath 《Geotechnical and Geological Engineering》2007,25(2):239-255
It is shown that time compression curve obtained from one-dimensional consolidation curve in the laboratory may include six
phases. These are initial compression, first primary compression, transition from first primary compression to second primary
compression, second primary compression, and transition from second primary compression to creep and lastly creep. This paper
attempts to identify the quantitative beginnings and characteristics of these phases. A mathematical characteristic of all
the soils that follow primary consolidation as per Terzaghi’s one dimensional consolidation theory is derived. It is known
as the constant of primary consolidation. It is used to study the beginning of secondary consolidation and its effects on
primary consolidation. Another characteristic of soils for creep and total absence of primary compression is derived. Methods
are suggested for the determination of coefficients of Primary and Secondary consolidations and the compression index. 相似文献