A study of characteristics of ground motion response spectra from earthquakes recorded in NE Himalayan region: an active plate boundary     

Babita Sharma  Sumer Chopra  P. Chingtham  Vikas Kumar 《Natural Hazards》2016,84(3):2195-2210

  相似文献   

Petrogenesis of Mesoproterozoic lamproite dykes from the Garledinne (Banganapalle) cluster,south-western Cuddapah Basin,southern India     

N. V. Chalapathi Rao  Atiullah  Alok Kumar  Samarendra Sahoo  Purnendu Nanda  Ngazimpi Chahong  B. Lehmann  K. V. S. Rao 《Mineralogy and Petrology》2016,110(2-3):247-268

  相似文献   

Stabilization of Expansive Soil with Cement Kiln Dust and RBI Grade 81 at Subgrade Level     

J. Sudheer Kumar  Upma Janewoo 《Geotechnical and Geological Engineering》2016,34(4):1037-1046

The present research work deals with an expansive high plastic clayey soil with cement kiln dust (CKD) and stabilizer (RBI Grade 81). The physical and engineering properties of soil are plasticity, compaction, unconfined compressive strength (UCS), consolidation and California bearing ratio (CBR) of the clayey soil and clay treated with CKD and stabilizer were determined. Soil chemistry was examined before and after treatment using scanning electron microscope (SEM) and elemental dispersive spectrometer. The clay mixed with CKD, CKD and RBI Grade 81 was found that optimum contents are 10 % (CKD), 15 % CKD with 4 % RBI Grade 81, respectively. The result indicates that CKD alone will decrease maximum dry density and increase optimum moisture content. CKD with RBI Grade 81 slightly increases maximum dry density and decreases optimum moisture content. UCS increased with CKD alone and CKD with RBI Grade 81 from 88.3 to 976 kN/m², respectively. CBR values were increased by the addition of CKD, CKD with RBI Grade 81 from 1.65 to 21.7 %. With the curing time of 3, 14 and 28 days, UCS and CBR values were increased due to pozzolanic reaction from cementations material. The treated soil has considerable reduction in compression index. SEM images clearly indicate the formation of CSH and CAH gel.  相似文献   

Selly,Richard C. and Sonnenberg,Stephen A. 2015. Elements of Petroleum Geology.     

Arun Kumar 《Marine Geodesy》2016,39(1):112-113

  相似文献   

Role of hydrological regime and floodplain sediments in channel instability of the Bhagirathi River,Ganga-Brahmaputra Delta,India     

Sanat Kumar Guchhait  Aznarul Islam  Balai Chandra Das  Nishith Kumar Maji 《自然地理学》2016,37(6):476-510

Abstract

This research deals with the surface dynamics and key factors – hydrological regime, sediment load, and erodibility of floodplain facies – of frequent channel shifting, intensive meandering, and lateral instability of the Bhagirathi River in the western part of the Ganga-Brahmaputra Delta (GBD). At present, the floodplain of the Bhagirathi is categorized as a medium energy (specific stream power of 10–300 W m^?2), non-cohesive floodplain, which exhibits a mixed-load and a meandering channel, an entrenchment ratio >2.2, width–depth ratio >12, sinuosity >1.4, and channel slope <0.02. In the study area, since 1975, four meander cutoffs have been shaped at an average rate of one in every 9–10 years. In the active meander belt and sand-silt dominated floodplains of GBD, frequent shifting of the channel and meander migration escalate severe bank erosion (e.g. 2.5 × 10⁶ m³ of land lost between 1999 and 2004) throughout the year. Remote sensing based spatio-temporal analysis and stratigraphic analysis reveal that the impact of the Farakka barrage, completed in 1975, is not the sole factor of downstream channel oscillation; rather, hydrogeomorphic instability induced by the Ajay–Mayurakshi fluvial system and the erodibility of floodplain sediments control the channel dynamics of the study area.  相似文献   

Effects of linear and exponential heterogeneity on the dynamic response of a moving load in an irregular isotropic half-space: a comparative study     

Abhishek Kumar Singh  Anirban Lakshman  Amares Chattopadhyay 《Geomechanics and Geoengineering》2016,11(3):201-218

Heterogeneity, being a trivial feature inside the earth or in a geostructure, makes a strong basis for its consideration in the study of geomechanics. Inclusion of the concept of heterogeneity along with irregularity in the medium brings a novelty to the existing literature related to the study of the moving load. The present study investigates the effects of linear and exponential heterogeneity on the dynamic response due to a normal load moving with constant velocity on a rough irregular heterogeneous isotropic half-space in a comparative approach. Expressions for both normal and shear stresses for either case of heterogeneity have been established in closed form. Substantial effects of the affecting parameters such as depth, irregularity factor, maximum depth of irregularity, frictional coefficient, linear heterogeneity parameter and exponential heterogeneity parameter on normal and shear stresses for both the cases of heterogeneity have been observed. Numerical computation has been carried out and the effects of said parameters have been meticulously examined by means of graphs. Moreover, different cases of heterogeneity and homogeneity along with various types of irregularity namely rectangular, parabolic and no irregularity are compared which serve as a focal theme of the study.  相似文献   

Influence of varying nitrogen levels on lipid accumulation in <Emphasis Type="Italic">Chlorella</Emphasis> sp.     

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 (N_0.1, N_0.25, N_0.5 and N_1.0 representing 0.1, 0.25, 0.5 and 1.0 g/L of sodium nitrate, respectively) and nitrogen-sufficient (N_1.5, 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 N_0.5, which is having one-third of nitrogen concentration present in original growth media, BG-11. This concludes N_0.5 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   

Multi-criteria decision analysis for planning and management of groundwater resources in Balod District,India     

Tarun Kumar  Amar Kant Gautam  D. C. Jhariya 《Environmental Earth Sciences》2016,75(8):649

  相似文献   

Seasonal variation in heavy metal contaminations in water and sediments of Jamshedpur stretch of Subarnarekha river,India     

Subhabrata Banerjee  Adarsh Kumar  Subodh Kumar Maiti  Abhiroop Chowdhury 《Environmental Earth Sciences》2016,75(3):265

  相似文献   

Temperature-dependent thermophysical properties of Ganurgarh shales from Bhander group,India     

A. K. Verma  Manish Kumar Jha  Sachin Maheshwar  T. N. Singh  R. K. Bajpai 《Environmental Earth Sciences》2016,75(4):300

  相似文献