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31.
Abani R Samal Raja R Sengupta Richard H Fifarek 《Journal of Earth System Science》2011,120(4):583-593
Linear trends of anomalously high gold values in the Florida Canyon gold deposit, Nevada have been identified using a combination
of contour maps of gold (Au) concentration developed with a geographic information system (GIS) and variogram maps created
using a geostatistical analysis package. These linear trends are interpreted to represent major fault zones that exerted a
prinicipal control on gold mineralization and therefore imparted a spatial anisotropy to gold concentrations. 相似文献
32.
We present properties of intensity oscillations of a sunspot in the photosphere and chromosphere using G band and Ca II H filtergrams from Hinode. Intensity power maps as function of magnetic field strength and frequency reveal reduction of power in the G band with an increase in photospheric magnetic field strength at all frequencies. In Ca II H, however, stronger fields exhibit more power at high frequencies, particularly in the 4.5–8.0 mHz band. Power distributions in different locations of the active region show that the oscillations in Ca II H exhibit more power compared to that of the G band. We also relate the power in intensity oscillations with different components of the photospheric vector magnetic field using near simultaneous spectro-polarimetric observations of the sunspot from the Hinode spectropolarimeter. The photospheric umbral power is strongly anti-correlated with the magnetic field strength and its line-of-sight component but there is a good correlation with the transverse component. A reversal of this trend is observed in the chromosphere except at low frequencies(ν≤ 1.5 mHz). The power in sunspot penumbrae is anti-correlated with the magnetic field parameters at all frequencies(1.0 ≤ν≤ 8.0 mHz) in both the photosphere and chromosphere, except that the chromospheric power shows a strong correlation in the frequency range 3–3.5 mHz. 相似文献
33.
The Franck-Condon factors and r-centroids, which are very closely related to vibrational transition probabilities, have been evaluated by the more reliable
numerical integration procedure for the bands of B
2 Σ+ - X
2 Σ+, C
2Σ+ - X
2 Σ+ andC
2 Σ+ - A
2 Πr systems of the astrophysical molecule BeF, using a suitable potential.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
34.
B. Karthikeyan V. Raja N. Rajamanickam S. P. Bagare 《Astrophysics and Space Science》2006,306(4):231-234
For molecular identification in astrophysical sources, an astrophysicist needs some spectroscopic parameters such as dissociation
energy, vibrational or rotational temperature of the source, band or line wavelengths, transition probability parameters,
etc. The Franck-Condon(FC) factors are proportional to the transition probabilities. In this study, the FC factors and r-centroids for the vibronic (vibration-electronic) transitions C
1 Σ + → X
1 Σ + of aluminium hydride (AlH), b
3 Σ ( −) → a
3 Π, C
1 Σ + → A
1 Π & C
′1 Δ → Δ 1 Π of boron hydride (BH) have been evaluated and the results are presented in tables which include band origin/head wavelengths.
The physical & astrophysical significances of our evaluated FC factors & r-centroids have been discussed and the possible presence of AlH in sunspot umbral spectra is also predicted.
PACS: 33 · 70 · Ca 相似文献
35.
本文通过约束大地测量研究来探索掸邦高原及其周围地区现今的地壳变形和长期块体运动,以期提供该地区地球动力学和相关地震危险状况的最新状态。掸邦高原在横向上由西侧的萨干(Sagaing)断裂和东侧的红河断裂这两条主要断裂包围。其中,青藏高原地壳的韧性流挤压被认为是该夹层变形单元变形的主要因素。大地测量清楚地表明,萨干断裂和红河断裂段分别具有约18 mm/a和约45 mm/a右旋运动走滑速率。此外,掸邦高原内部断层体系大地滑移累积表现为1213 mm/a的整体左旋运动速率。我们认为相对于刚性巽他古陆,研究区域的形变分布和长期块体运动主要受区域书架型断层作用控制,其原因是掸邦高原两侧的主断裂(萨干断裂和红河断裂)存在差异性断裂活动。 相似文献
36.
Hasan Raja Naqvi Javed Mallick Laishram Mirana Devi Masood Ahsan Siddiqui 《Arabian Journal of Geosciences》2013,6(10):4045-4056
The present comparative study is multi-temporal in nature. The Revised Universal Soil Loss Equation (RUSLE), remote sensing, and GIS were used to model the soil loss estimation for soil conservation and vegetation rehabilitation in Nun Nadi watershed for the years 2000 and 2009. The estimated mean soil loss for the year 2000 and 2009 is 3,283.11 and 1,419.39 Mg?ha?1 year?1, respectively. The study finds that about 80 % area has low or least risk of erosion and about 7 % is exposed to high or very high risk which indicates the improvement in terms of soil loss if we compare the data of both the time periods. The findings show that the rainfall, LULC change, and elevation are the main responsible factors for the soil loss in Nun Nadi watershed. Conservation measures have been adopted; however, the problem still remains serious and demands urgent attention. 相似文献
37.
Manzoor?A.?MalikEmail author Raja?Nisar?Ali Farooq?Ahmad 《Astrophysics and Space Science》2011,336(2):447-454
We derive the distribution function and the allied thermodynamic quantities for a system of galaxies with three mass species.
A new clustering parameter b
3 that inherently takes into account the masses and the number of galaxies of each kind, emerges directly from the calculations.
Our general conclusion is that the inclusion of the third component does not significantly effect the overall features of
the distribution function. 相似文献
38.
A. Raja Bayanna Shibu K. Mathew K. Sankarasubramanian P. Venkatakrishnan J. Singh B. R. Prasad 《Experimental Astronomy》2011,29(3):145-153
This paper addresses some of the issues related to externally occulted solar coronagraph; vignetting and achievable resolution
due to an external occulter. The analytical expression by Evans (J Opt Soc Am 38:1083–1085, 1948) is used to perform the initial calculations. An expression for the vignetting for a given external occulter and field angle
is derived. The values obtained with the derived expression are verified with those obtained by ZEMAX an Optical design software.
The degradation in angular resolution of the system due to vignetting is also presented and an empirical relation to calculate
the normalized resolution for a given amount of vignetting is obtained. 相似文献
39.
Isolation and characterization of phosphate-solubilizing bacteria from seagrass rhizosphere soil 总被引:1,自引:0,他引:1
Upasana Ghosh Ponnambalam Subhashini Elangovan Dilipan Subramanian Raja Thirunavukarassu Thangaradjou Lakshmanan Kannan 《中国海洋大学学报(英文版)》2012,11(1):86-92
Phosphate-solubilizing bacterial strains(6 Nos.) were isolated from the rhizosphere soils of two seagrasses(Halophila ovalis(R.Br.) Hook and Halodule pinifolia(Miki) Hartog) in the Vellar estuary.Experimental studies found that the strain PSSG6 was effective in phosphate solubilization with Phosphate Solubilization efficiency index E = 375 ± 8.54,followed by the strain PSSG5 with Phosphate Solubilization efficiency index E = 275 ± 27.3.Of the 6 strains isolated,the strains PSSG4 and PSSG5 be-longed to the genus Bacillus,and PSSG1,PSSG2 and PSSG3 were identified as Citrobacter sp.,Shigella sp.,and Klebsiella sp.,respectively,by conventional method,and PSSG6 was identified as Bacillus circulans using conventional and molecular methods. 相似文献
40.
Indian coastal waters are subjected to considerable pressure from sewage and industrial wastes, which are responsible for
the contamination of the coastal sediments with consequent loss in biosphere. The present investigation attempts to study
the significance of coarse material (Sand fraction) in the distribution of metals in polluted marine sediments. The study
revealed that coarse Sand component contains a relatively significant proportion of the anthropogenic metals (Cd, Cu, Pb and
Zn) and therefore it cannot be neglected in metal pollution studies of coastal sediments. Further, the distribution of anthropogenic
metals in both Silt + Clay and Sand fraction follow the same suit indicating similar pollution sources. From the total sediment
type (Silt + Clay and Sand fraction) all anthropogenic metals had a noticeable amount (>50%) in the acid extractable (and
potentially bio-available) fraction. This article stresses the importance of coarse fraction in metal pollution studies in
Indian coastal system. 相似文献