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41.
Thd H
3
+
molecular ion plays an important role in the chemistry of astronomical objects as it protonates the neutral species. The authors have recently calculated the partition functions of H
3
+
which may be used to compute the equilibrium constants for the chemical reaction H2+H2
+H
3
+
+H. In this short communication we have calculated the equilibrium constants for the temperature range from 500 to 8000 K. The results are also presented in the polynomial form. 相似文献
42.
Sneh Joshi Kireet Kumar Bimal Pande Mukesh Chandra Pant 《Meteorology and Atmospheric Physics》2013,120(3-4):177-187
The present study is an attempt to analyse the precipitable water vapour (PWV) derived from Global Positioning System (GPS) and observed meteorological data over Almora, Central Himalayan Region. The PWV values derived using GPS study is compared with the corresponding moderate resolution imaging spectro-radiometer (MODIS) data. The statistical analysis reveals a positive correlation between both methods. Moderate resolution imaging spectroradiometer near-infrared (MODIS NIR) clear column water vapour product shows a higher correlation (R 2 = 90–93 %) with GPS-derived precipitable water vapour on annual scale as compared to the seasonal scale (R 2 = 62–87 %). MODIS is found to be overestimating in NIR clear column where the magnitude of bias and RMSE show systematic changes from season to season. Monsoon is an important phenomenon in the Indian weather context and holds significant importance in Central Himalayan ecosystem. The monthly and seasonal variation in precipitable water vapour is related with monsoon onset in the region. Diurnal variations in precipitable water vapour are studied with other meteorological data over Almora during dry and wet season. The precipitable water vapour had minimum value in the morning, increases in the afternoon to evening and again decreases to the midnight in both the dry and wet seasons. These results suggest that diurnal variation of water vapour is caused by the transport of water vapour by thermally induced local circulation. 相似文献
43.
44.
ABSTRACT The Dhidhessa River Basin (DRB), in the Abbay River Basin in Ethiopia, is undergoing large-scale dam construction for sugarcane irrigation. We focused on the dynamics of population migration, settlement, relocation and water resource development in the DRB using primary and secondary data. Two major migration waves were observed in the basin: the first in 1984–1986 during a severe drought and the second during 2005–2017. Most rural migrants were “pulled” by government initiative in the period 1984–2017, while a few migrated of their own accord due to famine. We found that the first migration wave from eastern Ethiopia (Harar) to DRB was due to scarcity of water, land and rainfall and the migration positively affected migrant livelihoods. In the second phase, dam construction displaced settled farmers and migrants, adversely affecting their livelihoods. Analysis is needed that considers the wellbeing of the displaced agrarian society and the migrant population in the dam-affected area. 相似文献
45.
The equivalent widths of P(51) and R(43) lines of the 1-0 and P(45) and R(56) lines of the 2-1 vibration rotation bands of SiO near 8 m region, have been computed for Zwaan's (1974) sunspot model at the centre of the disc. The predicted equivalent widths suggest a possible presence of these SiO bands in the sunspot spectrum. 相似文献
46.
H. Pande Poonam S. Tiwari Shashi Dobhal 《Journal of the Indian Society of Remote Sensing》2009,37(3):395-408
Image fusion is the combination of two or more different images to form a new image by using a certain algorithm. Despite
the fact that the number and kind of satellite imagery are daily increasing, using fusion techniques, in a proper way, to
eliminate the redundancy in data and increase the quality of data is an important challenge in Remote Sensing Image Processing.
Fusion of multispectral images with a hyperspectral image generates a composite image which preserves the spatial quality
from the high resolution (MS) data and the spectral characteristics from the hyperspectral data. For the present study three
fusion algorithms (Principal Component Transformation, Colour Normalized and Gram-Scmidt Transformation) were analysed for
Hyperion and IKONOS MSS data. Their ability to preserve the spectral quality of fused data, in comparison with original hyper-spectral
image, has been investigated. 相似文献
47.
A new model for rocks and rock-like material with multiple planes of weakness is proposed. The behaviour of the assembly applies tensile and Mohr-Coulomb shear limits on each such plane with possible strain dependence of frictional properties. The visco-plastic algorithm which allows the incorporation of time effects is used to obtain static solutions. The model is illustrated in actual context by applications to stability of rock slopes and behaviour of tunnels. A generalization of the model to include arbitrary three-dimensional distribution of laminae in ‘quasi-plane strain’ is included. The effect of various flow rules adopted for plastic straining is indicated. 相似文献
48.
Rajneesh Bhutani Kanchan Pande T. R. Venkatesan 《Journal of Earth System Science》2004,113(4):737-754
New40Ar-39Ar thermochronological results from the Ladakh region in the India-Asia collision zone provide a tectono-thermal evolutionary
scenario. The characteristic granodiorite of the Ladakh batholith near Leh yielded a plateau age of 46.3 ± 0.6 Ma (2σ). Biotite from the same rock yielded a plateau age of 44.6 ± 0.3 Ma (2σ). The youngest phase of the Ladakh batholith, the leucogranite near Himya, yielded a cooling pattern with a plateau-like age
of ∼ 36 Ma. The plateau age of muscovite from the same rock is 29.8 ±0.2 Ma (2σ). These ages indicate post-collision tectono-thermal activity, which may have been responsible for partial melting within the
Ladakh batholith. Two basalt samples from Sumdo Nala have also recorded the post-collision tectono-thermal event, which lasted
at least for 8 MY in the suture zone since the collision, whereas in the western part of the Indus Suture, pillow lava of
Chiktan showed no effect of this event and yielded an age of emplacement of 128.2 ±2.6 Ma (2σ). The available data indicate that post-collision deformation led to the crustal thickening causing an increase in temperature,
which may have caused partial melting at the base of the thickened crust. The high thermal regime propagated away from the
suture with time. 相似文献
49.
Orimoloye Israel R. Olusola Adeyemi O. Belle Johanes A. Pande Chaitanya B. Ololade Olusola O. 《Natural Hazards》2022,112(2):1085-1106
Natural Hazards - Droughts are particularly disastrous in South Africa and other arid regions that are water-scarce by nature due to low rainfall and water sources. According to some studies,... 相似文献
50.
V. P. Gaur B. M. Tripathi G. C. Joshi M. C. Pande 《Astrophysics and Space Science》1988,147(1):107-113
Molecular dissociation equilibrium calculations were done for the model atmospheres of DA and non-DA white dwarfs. Our calculations show that He
2
+
and HeH+ appear as most abundant molecules in the atmospheres of non-DA white dwarfs while H2 and H
2
+
are most abundant molecules in DA white dwarfs. It is suggested that these molecules should be searched for in the atmospheres of white dwarfs. 相似文献