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排序方式: 共有136条查询结果,搜索用时 171 毫秒
111.
Mamilla Prathima Devi Motakatla Venkateswar Reddy Asha Juwarkar Ponnapalli Nageswara Sarma Srinivasula Reddy Venkata Mohan 《洁净——土壤、空气、水》2011,39(10):900-907
Ex‐situ bioremediation of real‐field crude petroleum sludge was evaluated to elucidate the role of co‐culture (bioaugmentation) and external nutrients supplementation (biostimulation) under anaerobic microenvironment. Maximum removal of total petroleum hydrocarbons (TPH) was observed by integrating biostimulation with bioaugmentation (R5, 44.01%) followed by bioaugmentation alone (R4, 34.47%), co‐substrate supplemented operations [R6, 23.36%; R3, 16.5%; R2, 9.88%] and control (R1, 4.36%). Aromatics fraction showed higher degradation in all the conditions studied. Fate of six selected polycyclic aromatic hydrocarbons (PAHs) was evaluated during bioremediation. Among these, four ring PAHs compounds showed good degradation by integration of biostimulation with bioaugmentation (R5) while bioaugmentation alone (R4) documented good degradation of three ring PAHs. Lower ring PAHs compounds showed good degradation with the application of biostimulation (R6). Fluorescent in situ hybridization (FISH) detected the presence of known PAHs degrading microorganisms viz., Bacillus, Pseudomonas, Acido bacteria, Sulphur reducing bacteria Firmicutes, etc. Application of biostimulation and bioaugmentation strategies alone or in combinations documented noticeable influence on the degradation of petroleum sludge. 相似文献
112.
V. Sharma Jahanbakhsh Daneshian L. Bhagyapati Devi 《Journal of the Geological Society of India》2011,78(2):157-166
Two intervals of faunal turnover are revealed by the study of radiolarians from the Early to Middle Miocene sequence of Andaman-Nicobar
belonging to Stichocorys wolffii-Calocycletta costata-Dorcadospyris alata zones. These faunal changes are reflected in the values of species diversity, change in abundance of taxa, origination and
extinction events and change in radiolarian assemblages. One such faunal change is identified in the latest Early Miocene.
The time of this faunal change is marked by the extinction of species like Carpocanopsis cingulata and appearance of Calocycletta costata, Giraffospyris toxaria, Acrocubus octopylus and Liriospyris parkerae, an increasing trend in percentage of cold water species and a decreasing trend in species diversity upwards. The interval
coincides with the time of initiation of cooling of sea surface water. Another, and the most prominent faunal turnover of
radiolarians is recognized in the Middle Miocene Dorcadospyris alata Zone at about 14.8–12.7 Ma and is characterized by almost complete disappearance of an earlier dominant assemblage and an
increase in abundance of an assemblage that was practically absent in the older sequence. The time of this turnover can be
correlated with the time of Middle Miocene cooling identified in the examined sequence. 相似文献
113.
R. P. Kachhara K. Bigyapati Devi R. L. Jodhawat 《Journal of the Geological Society of India》2011,78(1):81-91
Presence of oldest marine Tertiary rocks in Kachchh for a long time has remained debatable and controversial. To resolve the
issue in better way authors have worked out a section along tributary of Kakdi Nadi about 0.5 km west of village Nareda in
southwestern Kachchh and collected molluscan fauna. Systematic study of these fauna reveals presence of 15 taxa of which 12
are of bivalves and 3 of gastropods. This molluscan assemblage leads to the presence of marine Palaeocene sequence around
Nareda. Recorded assemblage hitherto not known earlier from Kachchh. 相似文献
114.
To study neotectonics, the structural and morphotectonic aspects are studied along a part of mountain front region of Northeast
Himalaya, Arunachal Pradesh, India. Unpaired river terraces are recognized near north of transverse Burai River exit, which
is cut by an oblique fault. Across this fault, fluvial terraces are located at heights of 22.7 and 3 m, respectively, on the
left and right banks. A water gap is formed along the river channel where the uplifted Middle Siwalik sandstone beds dipping
43° towards ENE direction, thrust over the Quaternary deposit consisting of boulders, cobbles, pebbles and sandy matrix. This
river channel incised the bedrock across the intraformational Ramghat Thrust along which the rocks of the Middle Siwalik Formation
thrust over the Upper Siwalik Formation. Recent reactivated fault activity is suggested north of the Himalayan Frontal Thrust
that forms the youngest deforming front of the Himalaya. The uplifting along the stream channel is noticed extended for a
distance of ~130 m and as a result the alluvial river channel became a bedrock river. The relative displacement of rocks is
variable along the length of strike–slip faults developed later within the Ramghat Thrust zone. Longitudinal and Channel gradient
profiles of Burai River exhibit knick points and increase in river gradient along the tapering ends of the profiles. The study
suggests active out-of-sequence neotectonically active thrusting along the mountain front. Neotectonics combined with climatic
factor during the Holocene times presents a virgin landscape environment for studying tectonic geomorphology. 相似文献
115.
K.K. Abdul Azeez T. Satish Kumar Sharana Basava T. Harinarayana A.M. Dayal 《Marine and Petroleum Geology》2011,28(5):1073-1082
As the Mesozoic sediments contribute most of the oil and gas reserves of the world, we present an integrated interpretation approach using magnetotellurics (MT) and surface geochemical prospecting studies to demarcate hydrocarbon prospective Gondwana (Mesozoic) formations underneath the Deccan flood basalts of Late Cretaceous age across Narmada-Tapti rift (between Bhusawal and Barwah) in Central India. The MT interpretation shows deep (∼5 km) basement structure between southern and central part of the MT profile however, it gradually becomes shallower to either ends of the profile with a predominant basement depth reduction in the northern end compared to the southern end. The geophysical results suggest thick (2-3.5 km) Mesozoic sediments in the area characterized by deep basement structure. The geochemical analysis of the near surface soil samples indicate higher concentrations of light gaseous hydrocarbons constituents over the area marked with thick sub-basalt Mesozoic formations. Analyses of the geochemical data imply that these hydrocarbons are genetically related, generated from a thermogenic source and these samples fall in the oil-producing zone. The temperature-depth estimations in the region supports favorable temperature conditions (80-120 °C) for oil generation at basement depths. 相似文献
116.
117.
N. Ibotombi Singh L. Debala Devi Th. Yaiphalembi Chanu 《Journal of the Geological Society of India》2013,82(2):121-132
The southern Manipur Ophiolitic Complex in the Indo-Myanmar Orogenic Belt, Northeast India comprises a set of serpentinised peridotites, pelagic sediments, podiform chromitites with minor mafic and felsic intrusives. Peridotites in the study area suffered various degrees of serpentinisation and also have been highly deformed and metamorphosed. Striations and slickenside surfaces are common features seen in these rocks indicating the effect of faulting or shearing due to tectonic movement. On the basis of mineralogy and modal composition these peridotites have been identified as serpentinised harzburgite, lherzolite, serpentinite with minor wehrlite. The serpentine minerals are mainly lizardite and chrysotile with sub-ordinate antigorite, whereas, pyroxenes are enstatite and diopside. The primary composition of Cr-spinels in these serpentinised peridotites are characterized by low SiO2 (<0.11 wt.%), Fe2O3 (0.02 to 2.32 wt.%), TiO2 (<0.15 wt.%), Cr# (0.13 to 0.23) and high Al# (0.74 to 0.86), Mg# (0.68 to 0.73). Olivine is relatively uniform in composition, ranges from Fo89.64 to Fo90.1. The mineralogical compositions and primary Cr-spinel chemistry of these peridotites are similar to Abyssal peridotites that formed in a mid-ocean ridge setting after low degree of partial melting. Thus, it supports that the mantle peridotites of the Manipur Ophiolitic Complex initially formed in a spreading regime. 相似文献
118.
Noble P. Abraham Sijo Sebastian G. Sreekala Savithri E. Devi G. Renuka Venugopal Chandu 《Astrophysics and Space Science》2014,349(1):49-55
A popular model of a cometary plasma is hydrogen (H+) with positively charged oxygen (O+) as a heavier ion component. However, the discovery of negatively charged oxygen (O?) ions enables one to model a cometary plasma as a pair-ion plasma (of O+ and O?) with hydrogen as a third ion constituent. We have, therefore, studied the stability of the ion-acoustic wave in such a pair-ion plasma with hydrogen and electrons streaming with velocities $V_{d\mathrm{H}^{+}}$ and V de , respectively, relative to the oxygen ions. We find the calculated frequency of the ion-acoustic wave with this model to be in good agreement with the observed frequencies. The ion-acoustic wave can also be driven unstable by the streaming velocity of the hydrogen ions. The growth rate increases with increasing hydrogen density $n_{\mathrm{H}^{+}}$ , and streaming velocities $V_{d\mathrm{H}^{+}}$ and V de . It, however, decreases with increasing oxygen ion densities $n_{\mathrm{O}^{+}}$ and $n_{\mathrm{O}^{-}}$ . 相似文献
119.
Wahyudi A’an J. Rahmawati Susi Irawan Andri Hadiyanto Hadiyanto Prayudha Bayu Hafizt Muhammad Afdal Afdal Adi Novi S. Rustam Agustin Hernawan Udhi. E. Rahayu Yusmiana P. Iswari Marindah Y. Supriyadi Indarto H. Solihudin Tubagus Ati Restu Nur Afi Kepel Terry L. Kusumaningtyas Mariska A. Daulat August Salim Hadiwijaya L. Sudirman Nasir Suryono Devi D. Kiswara Wawan 《Ocean Science Journal》2020,55(1):85-97
Ocean Science Journal - Seagrass meadows provide critical ecosystem services for coastal areas, e.g., as nursery habitats for various fish species, help with water filtration of suspended sediment,... 相似文献
120.
Mountainous basins like the Upper Indus Basin(UIB) of Gilgit Baltistan(GB) are dependent on seasonal snowmelt and glacier melt. Monitoring of the snow-covered area(SCA) is not only vital for the overall hydrology of the Indus basin but also important to the sustainable agriculture and hydropower system. The snow-covered area in the UIB of GB was investigated for changes over the last 18 years using the Moderate Resolution Imaging Spectroradiometer(MODIS) snow product. The study area was divided into five elevation zones ranging from 877-8564 meters above sea level(m ASL). In contrast to the global cryosphere related studies, SCA in the UIB is slightly increasing. Elevation based SCA analysis also indicated that SCA is slightly increasing in each elevation zone. However, a significant amount of snow is concentrated in areas above 5000 m ASL. Due to the strong correlation between SCA and precipitation, the precipitation data also follow a similar trend. Analysis of the climatic data suggests a statistically significant increase in total monthly precipitation and relative humidity, a slight decrease in mean monthly temperature and a significant upward tendency in monthly solar irradiance data. All these trends in combination with the increasing trend in global precipitation, winter westerly disturbances and orographic precipitation are the important factors behind the slightly increasing SCA in the study area. Our results though constrained by short observation period mainly contribute to the understanding of advancing snow cover and glaciers in Hindukush Karakoram. 相似文献