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1.
It is suggested that a collapsing supermassive object, which acts as an ultra-high energy particle accelerator, is the precursor of an active galactic nucleus and that the gravitational energy released during the collapse of the object is locked in the quark-gluon plasma permeated by leptons into which the entire matter in the core of the object is converted as a result of the collapse. It is also pointed out that the collapse of the object to a space-time singularity is inhibited by Pauli's exclusion principle as well as by Heisenberg's uncertainty principle and that the object explodes, before it could collapse to a singularity, thereby releasing the enormous amount of energy locked in the quark-gluon plasma.  相似文献   
2.
Satyavani  N.  Shankar  Uma  Thakur  N.K.  Reddi  S.I. 《Marine Geophysical Researches》2002,23(5-6):423-430
Multi-channel seismic reflection data from the western continental margin of India (WCMI) have been analyzed to construct a plausible model for gas hydrate formation. A reflector at 2950 ms two way travel time (TWT) on one of the sections is interpreted to represent the base of the layer of the methane hydrate, identified by a bottom simulating reflector (BSR) that lies almost 500 ms beneath the sea floor. BSRs of similar origin are common world wide, where they are usually interpreted to mark the base of gas hydrate bearing clastic sediment, with or without underlying free gas. In this study we present a model with the contrasting physical properties that produce synthetic wavelets that match with the observed BSR amplitude and waveforms for varying source-receiver offsets of multi-channel seismic reflection data. The preliminary results presented here put important constraints on models that predict the distribution and formation of hydrate. Offset-dependent amplitude recovery also gives an appropriate response for hydrate characterization.  相似文献   
3.
4.
The previously described potent biodegrading bacterial strain Serratia sp. ISTVKR1 isolated from sludge of Vasant Kunj Sewage Treatment Plant (VK STP) was used for the study of detoxification of municipal wastewater contaminants with the help of in vitro bioassays conducted on human liver cancer cell line HepG2. The strain has previously been shown to reduce wastewater contaminant load as revealed by a sevenfold reduction in COD and removal of some organic contaminants in the GC–MS analysis of wastewater post-72-h bacterial treatment. Cytotoxicity, genotoxicity and dioxin-like behavior of real municipal wastewater (collected from inlet of VK STP) was assessed before and after bacterial treatment using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), alkaline comet and 7-ethoxyresorufin-O-deethylase (EROD) assays, respectively. The bacterial strain was inoculated into MSM broth (pH = 7.2) containing 50% v/v filter-sterilized influent of VK STP and incubated up to 240 h at 30 °C and 130 rpm. Physicochemical and toxicological analyses were performed for the culture samples. The results of bioassays revealed an increase in cell viability by 40.16% and a reduction in the % EROD activity by 58.4% in the 240-h bacteria-treated sample as compared to the 0-h sample. Genotoxicity as indicated by tail moment (TM) and olive tail moment (OTM) was found to reduce by five- and threefold, respectively, after 240-h bacterial treatment. The results of the study confirmed the potency of the bacterial strain in detoxification of wastewater contaminants.  相似文献   
5.
Indole is a highly recalcitrant aromatic heterocyclic organic compound consisting of a five-membered nitrogen-containing pyrrole ring fused to a six-membered benzene ring. This study presents the results of the electro-chemical mineralization of indole in an aqueous solution using platinum-coated titanium (Pt/Ti) electrode. A central composite design was used to investigate the effect of four parameters namely initial pH (pHo), current density (j), conductivity (k) and treatment time (t) at 5 levels. Multiple responses namely chemical oxygen demand (COD) removal (Y 1) and specific energy consumption (Y 2) were simultaneously maximized and minimized, respectively, by optimizing the parameters affecting the mineralization of indole by using the desirability function approach. At the operating conditions of pH 8.6, j = 161 A/m2, k = 6.7 mS/cm and t = 150 min, 83.8% COD removal with specific energy consumption of 36.3 kWh/kg of COD removed was observed. Ultra performance liquid chromatography, UV–visible spectroscopy, Fourier transform infrared spectroscopy and cyclic voltammetry of the indole solution were performed at the optimum condition of the treatment so as to report a plausible mechanism of indole degradation. Field emission scanning electron microscopy analysis of electrodes before and after treatment was performed for determining the changes on anode surface during the treatment. Thermal analysis of the solid residue (scum) obtained was also performed for exploring its disposal prospects. Present study shows that electro-chemical oxidation can be used for mineralization of nitrogenous heterocyclic compounds such as indole.  相似文献   
6.
In river bank filtration, impurities present in the river water travel with the bank filtrate towards the pumping well. During this passage, certain types of impurities, such as turbidity, total coliform, and so forth, may get attenuated; however, it is interesting to note that some of the instant raw river water quality parameters, such as alkalinity and electrical conductivity, increase after the passage of water through the porous medium. This occurs because water, when passing through the soil pores, absorbs many of the solutes that cause an increase in alkalinity and electrical conductivity. Measurements at a river bank filtration site for a year showed that alkalinity of 116–32 mg l?1 in river water increased to 222.4–159.9 mg l?1 in the river bank filtered water. Likewise, the electrical conductivity increased from 280–131 μS cm?1 to 462–409.6 μS cm?1. This study uses a probabilistic approach for investigating the variation of alkalinity and electrical conductivity of source water that varies with the natural logarithm of the concentration of influent water. The probabilistic approach has the potential of being used in simulating the variation of alkalinity and electrical conductivity in river bank filtrate. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
7.
The plots of axial ratios, X/Y and Y/Z, of deformed pebbles of quartz and quartzite occupy the constriction field. It is proved by comparision of observed data with the theoretical models, that the finite shapes of deformed pebbles showing constriction-type deformation ellipsoid has resulted due to superimposition of the schistosity forming flattening-type deformation of F2 phase on the nappe forming flattening-type of F1 deformation phase. The deformed shapes of pebbles indicate that the principal direction of maximum extension (X) of the finite deformation ellipsoid lie parallel to subparallel to the axial directions of F2 and F3 folds.
Zusammenfassung Diagrammdarstellungen der Achsenverhältnisse X/Y und Y/Z ergeben für deformierte Quarz- und Quarzitgerölle eine Lage im Konstriktionsfeld. Durch Vergleich der Beobachtungsdaten mit theoretischen Modellen wird nachgewiesen, daß die finiten Umrisse deformierter Gerölle mit einem Deformationsellipsoid vom Konstriktionstyp sich aus der überlagerung der die Schieferung verursachenden Deformationsphase F2 mit Plättungstyp über die deckenbildende Deformationsphase F1 mit Plättungstyp ergaben. Die deformierten Umrisse der Gerölle zeigen, daß die Hauptrichtung größter Extension (X) des finiten Deformationsellipsoides parallel oder annähernd parallel zur Achsenrichtung der F2- und F3-Falten liegt.

Résumé Les diagrammes de rapports d'axes X/Y et Y/Z relatifs à la déformation de galets de quartz et de quartzite montrent une localisation dans un champ de constriction. En comparant les données de l'observation avec des modèles théoriques on voit que les contours des galets déformés suivant un ellipsoÏde de déformation du type constriction résultent de la superposition de la phase de déformation F2, du type applatissement, déterminant la schistosité, sur la phase de déformation F1, du mÊme type, liée aux nappes. Les contours déformés des galets montrent que la direction principale de la plus grande extension (X) de l'ellipsoÏde de déformation affine est parallèle, ou approximativement parallèle, à la direction des axes des plis F2 et F3.

X/Y Y/Z . , F2, , F1 . , (X) , F2 F3.
  相似文献   
8.
Application of geostatistics in estimating recoverable reserves of beach sand deposit is rare. This paper made an attempt to estimate local recoverable reserves using disjunctive kriging and discrete Gaussian model considering support and information effects for a beach sand deposit located in the eastern part of India. The dependence of different selective mining unit (SMU) sizes and different production sampling strategies on the estimated tonnage, metal quantity, and the ore tonnage versus metal quantity relationships has been examined. The results of the study show that nonlinear geostatistics should be used for more precise assessment of the grade, ore tonnage, and metal quantity and their relationships, which are necessary for recoverable reserve estimation. In selective mining operation, both support and information effects have significant influence on recoverable reserve. Recoverable reserve estimation based on SMU involves estimating grade distributions of mining unit with much bigger support than the available drill core sample data. Information effect comes into picture from the real scenario where the actual grades of the blocks remain unknown even during mining. At the mining stage, discrimination of ore and waste blocks is carried out based on estimated grades of the production samples and it is likely that the blocks might be misclassified as either ore or waste and thus sent to wrong destination. Information effect modeling makes the estimation more reliable by taking care of misclassification.  相似文献   
9.
The Kangra reentrant constitutes a ~ 80-km-wide zone of fold-thrust belt made of Cenozoic strata of the foreland basin in NW Sub-Himalaya. Earlier workers estimated the total long-term shortening rate of 14 ± 2 mm/year by balanced cross-section between the Main Boundary Thrust and the Himalayan Frontal Thrust. Geologically estimated rate is nearly consistent with the GPS-derived slip rate of 14 ± 1 mm/year. There are active faults developed within 4–8 km depth of the Sub-Himalayan fold-thrust belt of the reentrant. Dating the strath surfaces of the abandoned fluvial terraces and fans above the thrust faults, the uplift (bedrock incision) rates are computed. The dips of thrust faults are measured in field and from available seismic (depth) profiles. From the acquired data, late Quaternary shortening rates on the Jawalamukhi Thrust (JT), the Soan Thrust (ST) and the Himalayan Frontal Thrust (HFT) are estimated. The shortening rates on the JT are 3.5–4.2 mm/year over a period 32–30 ka. The ST yields a shortening rate of 3.0 mm/year for 29 ka. The corresponding shortening and slip rates estimated on the HFT are 6.0 and 6.9 mm/year during a period 42 ka. On the back thrust of Janauri Anticline, the shortening and slip rates are 2.0 and 2.2 mm/year, respectively, for the same period. The results constrained the shortening to be distributed largely across a 50-km-wide zone between the JT and the HFT. The emergence of surface rupture of a great and mega earthquakes recorded on the reactivated HFT implies ≥100 km width of the rupture. The ruptures of large earthquakes, like the 1905 Kangra and 2005 Kashmir, remained restricted to the hinterland. The present study indicates that the high magnitude earthquakes can occur between the locking line and the active thrusts.  相似文献   
10.
Human activities in many parts of the world have greatly changed the natural land cover. This study has been conducted on Pichavaram forest, south east coast of India, famous for its unique mangrove bio-diversity. The main objectives of this study were focused on monitoring land cover changes particularly for the mangrove forest in the Pichavaram area using multi-temporal Landsat images captured in the 1991, 2000, and 2009. The land use/land cover (LULC) estimation was done by a unique hybrid classification approach consisting of unsupervised and support vector machine (SVM)-based supervised classification. Once the vegetation and non-vegetation classes were separated, training site-based classification technology i.e., SVM-based supervised classification technique was used. The agricultural area, forest/plantation, degraded mangrove and mangrove forest layers were separated from the vegetation layer. Mud flat, sand/beach, swamp, sea water/sea, aquaculture pond, and fallow land were separated from non-vegetation layer. Water logged areas were delineated from the area initially considered under swamp and sea water-drowned areas. In this study, the object-based post-classification comparison method was employed for detecting changes. In order to evaluate the performance, an accuracy assessment was carried out using the randomly stratified sampling method, assuring distribution in a rational pattern so that a specific number of observations were assigned to each category on the classified image. The Kappa accuracy of SVM classified image was highest (94.53 %) for the 2000 image and about 94.14 and 89.45 % for the 2009 and 1991 images, respectively. The results indicated that the increased anthropogenic activities in Pichavaram have caused an irreversible loss of forest vegetation. These findings can be used both as a strategic planning tool to address the broad-scale mangrove ecosystem conservation projects and also as a tactical guide to help managers in designing effective restoration measures.  相似文献   
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