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In this study, we report for the first time, the occurrence of pothole features and the processes of their development on the bedrocks of Ghaghghar River, Son valley, India. Pothole geometries were identified and measured from the middle reaches of Ghaghghar River, where it is flowing exclusively over the Rohtas limestone (a Meso-Proterozoic age) of Vindhyan Supergroup, near to the Gurma village. On the basis of field survey and remote sensing study, it has been ascertained that potholes developed in the river bed were only related to local geological and geomorphological conditions of a stream. They are mainly developed due to abrupt slope change along the river course and usually associated with intersect fractures, joints, and veins in the bedrock. The knick point of the river profile also confirms the abrupt slope change of the river in Gurma region. The river changes its course from E-W to N-S due to Markundi fault (ENE-WSW) occurring in the study area and causes the tectonic disturbances to support the development of potholes. The formations of potholes on bedrock of Ghaghghar River were generally governed by abrasion of rock fragments during high-flow regime. The geometrical dimensions of the potholes are controlled by the joints, fractures, and veins developed in bedrock of the river. The veins are typically calcitic in nature and the orientations of long axis of potholes are analogous to the trend direction of the vein. The collapse bedrocks suggest that a pothole can be formed within a short period, but cannot be fully developed and maintained for a long time in a strong incision of riverbed.

The current study describes the land use and land cover dynamics in Eastern Arunachal Pradesh from 1985 to 2005 using remote sensing and Geographical Information System (GIS). Landsat-MSS, IRS-LISS-I and LISS-III data for the period 1985, 1995 and 2005 were used to prepare the land use/land cover (LULC) map at 1:250K for different periods. Post-classification change detection technique for quantifying the changes for twelve major land use and land cover types was analyzed. The study signifies that the region experiences expansion in crop land and built-up area and decline in forest area. Crop land and built-up area has increased by 665.41 km2 and 16.72 km2, respectively, from 1985 to 2005. On the other hand, forest area has declined by 699.37 km2 during the period. The study showed that topography and increasing population play an important role in shaping the LULC pattern. The study further revealed the importance of satellite remote sensing and GIS as an effective approach for analyzing the direction, rate and spatial pattern of land use dynamics. It is believed that this type of study will help to contribute towards sustainable land-use planning and management in this part of the North East India in the near future.

Late Paleocene sedimentation in the pericratonic Kachchh Basin marks the initial marine transgression during the Cenozoic era. A 17 m thick sandstone-dominated succession, known as the clastic member (CM) of the Matanomadh Formation (MF), is exposed sporadically in the basin. Three facies associations are reconstructed in the succession in three different sections. Facies association-1 contains matrix-supported pebbly conglomerate facies, horizontally-laminated sandstone-mudstone alternation facies, hummocky- and swaley cross-bedded sandstone facies, wave-rippled sandstone facies and climbing ripple cross-laminated sandstone facies. This facies association developed between shoreface and foreshore zone under the influence of storms on a barrier ridge. Facies association-2 contains sigmoidal cross-bedded sandstone facies, sandstone-mudstone alternation facies, flaser-bedded sandstone facies, herringbone cross-bedded sandstone facies and tangential cross-bedded sandstone facies. This facies association possessing tidal bundles and herringbone cross-beds developed on a tidal flat with strong tidal influence. Facies association-3 comprises pebbly sandstone facies, horizontally-bedded sandstone facies, tangential cross-bedded sandstone facies exhibiting reactivation surfaces and tabular cross-bedded sandstone facies. This facies association represents sedimentation in a river-dominated estuary and reactivation surfaces and herringbone cross-beds indicating tidal influence. The bipolar paleocurrent pattern changes to unipolar up-section because of the change in the depositional currents from tidal to fluvial. The sedimentation took place in an open coast similar to the Korean coast. The presence of neap-spring tidal rhythmites further suggests that a semidiurnal system similar to the modern day Indian Ocean was responsible for the sedimentation. Here, the overall sequence developed during the transgressive phase where barrier ridge succession is succeeded by the tidal flat succession and the latter, in turn, is succeeded by the estuarine succession. This study resolves the most debated issue of initial marine transgression in the Kachchh Basin during the Cenozoic.

Cenozoic era was the turning point in the geological history of the Indian subcontinent when India experienced maximum isolation before it collided with Asia and there occurred a great mountain building activity shaping the Himalaya. In the Cenozoic era, the sedimentation commenced in the late Paleocene (∼57.9 Ma) in the pericratonic basins of the western India as well as the foreland basins of the Himalaya that marks the beginning of a major transgression on the Indian subcontinent. Till now, it is not sure whether this transgression was forced by tectonics or climate. We have interpreted that the primary driver for this transgression was the tectonics that marks the beginning of the India–Asia convergence. A major regression of similar magnitude occurred during latest middle Eocene (41.3–38.0 Ma) that corresponds to global sea-level fall. This regression is global and can be identified even in the Cenozoic basins developed within the African plate. It is interpreted that this regression was driven by the global cooling during latest middle Eocene/late Eocene possibly associated with the nucleation of the Antarctica ice-sheets coupled with the uplift of the Himalaya.

Provenance of the late Paleocene sandstone of the Jaisalmer basin has been determined by petrographic and heavy minerals analysis supported by paleocurrent study. Petrography of the quartzose-arenite sandstone reveals an abundance of sub-angular to sub-rounded monocrystalline non-undulatory quartz and some amount of feldspar and rock fragments. The rock fragments are dominated by argillites (slate, phyllite) and limestone. The heavy minerals suite of these sandstones comprises of angular to sub-angular grains of magnetite, zircon, tourmaline, kyanite and staurolite. The paleocurrent analysis indicates bipolar paleocurrent pattern with the dominance of NW flow suggesting that the provenance was in the SE direction of the depositional basin. Q-F-L and Qm-F-Lt diagrams suggest for a provenance at the margin of the craton interior and transitional continental. It is envisaged that the basic igneous rocks of the Deccan basalt, low- to medium-grade metamorphic rocks of the Aravalli belt and Jurassic limestones present in the vicinity are the source rocks for the late Paleocene sandstones of the Jaisalmer basin.

A three-component broadband seismograph is in operation since January 2007 at the Indian School of Mines (ISM) campus, Dhanbad. We have used the broadband (BB) seismograms of 17 teleseismic events (M ≥ 5.8) recorded by this single BB station during 2008-09 to estimate the crust and upper mantle discontinuities in Dhanbad area which falls in the peninsular India shield. The converted wave technique and the Receiver function analysis are used. A 1-D velocity model has been derived using inversion. The Mohorovicic (Moho) discontinuity (crustal thickness) below the ISM observatory is estimated to be ~41 km, with an average Poisson ratio of ~0.28, suggesting that the crust below the Dhanbad area is intermediate to mafic in nature. The single station BB data shed new light to the estimate of crustal thickness beneath the eastern India shield area, which was hitherto elusive. Further, it is observed that the global upper mantle discontinuity at 410 km is delayed by ~0.6 sec compared to the IASP-91 global model; this may be explained by a slower/hotter upper mantle; while the 660 km discontinuity is within the noise level of data.

Carbon stock distribution in different tropical forest types in India is rarely studied although India is a country with mega-diversity. The present study estimates the biomass and carbon stock of major tropical forest types in India, and attempts to identify suitable interpolation techniques for mapping carbon stock. Empirically derived allometric equations and carbon conversion coefficients were used to estimate the aboveground biomass and carbon stock, respectively. The point estimates were interpolated to spatial surface using different interpolation techniques. Two main modelling approaches were implemented: deterministic modelling and stochastic modelling. Deterministic modelling was to interpolate point information using similarities between measured points (inverse distance weighted (IDW) interpolation), and fitting a smoothing curve along the measured points (polynomial interpolation). In stochastic modelling, ordinary kriging (OK) was employed using parameters derived from semivariograms. The re...

Before flue gases are released to the atmosphere the pollutants present in them are treated by passing the gases through monolithic converters. Mathematical modelling is an important tool to understand the processes taking place in the converter and it plays an integral part in designing and improving the existing models. In the present study, heat and mass transfer taking place in the monolith channel for oxidation of hydrocarbon propylene has been considered. Model equations have been formed for both homogenous and heterogeneous reactions. The results obtained from the two reaction mechanisms have also been compared.

Modeling for catalytic oxidation of a volatile organic compound, acetaldehyde for the purpose of controlling tail-pipe emissions from vehicular exhaust was carried out. The model developed was one-dimensional unsteady state model, using mass and energy balance equations to predict results for acetaldehyde conversion in an adiabatic monolith operating under warm-up conditions. The equations consisted of a set of partial differential equations that are coupled and solved using Backward Implicit Scheme. Analysis of the behavior of the converter during warm up period was carried out and it was observed that the warm up was faster for a fresh catalyst and this warm up period could be reduced by introducing hot incoming exhaust gas at higher temperature.

A three-component broadband seismograph is in operation since January 2007 at the Indian School of Mines (ISM) campus. We have used the broadband seismograms of two local earthquakes M

The one-dimensional models for catalytic converters are used to account for the reduction of pollutants like hydrocarbons (HC), carbon monoxide (CO) and nitric oxide (NO). The proposed model considers both gaseous as well as solid phase reactions of only one gas propylene that could possibly be occurring in the converter channels. Metal substrates were considered, as the better heat conducting solid material. The Runge–Kutta method and backward implicit schemes were employed to solve the coupled ordinary and partial differential equations.

The problem of gas absorption into a falling film reactor was studied in the case of an instantaneous reaction. A diffusion-convection-reaction model was developed taking momentum, mass and heat transfer effects into account. The performance of the model was examined for sulphonation of tridecylbenzene. The resultant equations were solved using a finite difference backward implicit scheme. The results indicated an increase in the axial temperature of the liquid film for a short distance from the reactor top and the predicted conversion was in close agreement with the experimental results.

The treatment of non-Newtonian fluids in tubular reactors is frequently encountered in industries, which may be studied by mathematical modeling. The modeling of endothermic reactions of non-Newtonian fluids in tubular reactors with radial dispersion has been done for Ostwald-de-Waele power law fluids. The coupled mass balance, heat balance and velocity equations have been dealt with. The model is solved using finite difference numerical methods. The effect of variation in the dimensionless parameters of the model has also been studied. In addition, the rheological parameter n also affects the reactor performance as well as the velocity profile. An increase in n leads to higher velocity distortion and a decrease in conversion and temperature.

Model equations describing the absorption of gas in a liquid film falling down a vertical wall were solved for the case of zero, first, and second order reaction by the method of backward implicit finite difference numerical scheme. The concentration profiles thus obtained were used to evaluate absorption rates and enhancement factors for Newtonian and non-Newtonian fluids. The predicted results were compared with published literature to confirm the validity of the model. Effect of interfacial drag on gas absorption with chemical reaction was also studied. The results indicated that shear stress increases the rate of absorption in case of cocurrent flow and vice versa for countercurrent condition.

A series of 5-[( N -substituted benzylidenylimino)amino]-2-oxo/thiobarbituric acids (3a–3h) have been synthesized by the condensation of 5-hydrazino-2-oxo/thiobarbituric acids (2a–2b) with various aromatic aldehydes. Cycloaddition of thioglycolic acid to 3a–3h , yielded 5-[(2′-substituted phenyl-4′-oxothiazolidin-3′-yl)amino]-2-oxo/thiobarbituric acids (4a–4h) . All these compounds were screened, in vivo, for their anticonvulsant activity and acute toxicity studies. Compounds 4f and 4g were found to be most potent compounds of this series and were compared with the reference drugs, phenytoin sodium, lamotrigine and sodium valproate. The structures of these compounds have been established by IR, 1 H NMR and mass spectroscopic data.

In this article, we consider the estimation of a population mean when some observations on the study characteristic are missing in the bivariate sample data. In all, five estimators are presented and their efficiency properties are discussed. One estimator arises from the the amputation of incomplete observations while the remaining four estimators are formulated using imputed values obtained by the ratio method of estimation.

India has experienced significant Land-Use and Land-Cover Change (LULCC) over the past few decades. In this context, careful observation and mapping of LULCC using satellite data of high to medium spatial resolution is crucial for understanding the long-term usage patterns of natural resources and facilitating sustainable management to plan, monitor and evaluate development. The present study utilizes the satellite images to generate national level LULC maps at decadal intervals for 1985, 1995 and 2005 using onscreen visual interpretation techniques with minimum mapping unit of 2.5 hectares. These maps follow the classification scheme of the International Geosphere Biosphere Programme (IGBP) to ensure compatibility with other global/regional LULC datasets for comparison and integration. Our LULC maps with more than 90% overall accuracy highlight the changes prominent at regional level, i.e., loss of forest cover in central and northeast India, increase of cropland area in Western India, growth of peri-urban area, and relative increase in plantations. We also found spatial correlation between the cropping area and precipitation, which in turn confirms the monsoon dependent agriculture system in the country. On comparison with the existing global LULC products (GlobCover and MODIS), it can be concluded that our dataset has captured the maximum cumulative patch diversity frequency indicating the detailed representation that can be attributed to the on-screen visual interpretation technique. Comparisons with global LULC products (GlobCover and MODIS) show that our dataset captures maximum landscape diversity, which is partly attributable to the on-screen visual interpretation techniques. We advocate the utility of this database for national and regional studies on land dynamics and climate change research. The database would be updated to 2015 as a continuing effort of this study.

The nonlinear Boussinesq unsteady-state differential equation used for evaluating drainage of sloping lands with drains lying at a distance above the impermeable layer was solved. A combination of explicit and implicit difference methods was used to obtain a finite-difference solution for a linearized system of equations of Graute-Nicolson type on two time levels, ensuring the stability of the solution. The maximum height of the water tables was obtained as a function of time for different slopes varying from 0 to 70%. Model results were compared with the available experimental solutions of Luthin and Guitjens and Chauhan et al. as well as the numerical solution of Moody and were found to be in reasonable agreement.

This paper considers the estimation of the ratio of population means when some observations are missing. Four estimators are presented and their bias and mean square error properties are studied.

This paper presents a comparative study of the performance properties of one unbiased and two Stein-type estimators for combining the estimates of coefficients in a linear regression model when data sets are available from replicated experiments conducted at possibly different stations.

Schottky devices were fabricated by thermal evaporation of indium on chemically synthesized polyaniline, poly(o-anisidine), and poly( aniline-co-ortho-anisidine) copolymer. Electrical characterization of each of these devices was carried out using current (I)-voltage (V) and capacitance (C)-voltage (V) measurements. The value of various junction parameters such as rectification ratio, ideality factor, and barrier heights of an In/poly(aniline-co-o-anisidine) Shootky device were found to be 300, 4.41, and.4972 V compared to the values of 60, 5.5, and 0.5101 V obtain for an In/polyaniline device, respectively.

This article considers a misspecified linear regression model in which misspecification relates to the inclusion of some explanatory variables. Assuming the distribution of disturbances to be not necessarily normal, this paper investigates the efficiency properties of predictions arising from ordinary least squares and Stein-rule when the aim is to predict either the actual value or the mean value of the study variable.

This paper considers Zellner's two estimators in a seemingly unrelated regression equations (SURE) model. Efficiency properties of the two estimators are analyzed by asymptotic expansions and Monte Carlo experiments under non-normal disturbances. It is shown that the two estimators have the same efficiency up to the second-order terms of O(T − 1 2 ) , and that non-normality influences the rate of convergency to normality of the estimators.

The least squares estimation of the slope parameter of a simple linear regression is biased if the regressor variable is measured with random errors. This bias as well as the mean squared error is computed up to the order of 1/T without assuming normality for the error variable. They depend on the fourth moment of the error variable.

This paper considers the application of Stein-type estimation procedure for the coefficients in a linear regression model when data are available from replicated experiment. Two families of estimators characterized by a single scalar are proposed and their large sample asymptotic properties are derived. These are utilized for comparing the performances of the two estimators along with the conventional estimator and conditions for the superiority of one estimator over the other are deduced.

In this paper we have provided a general result on the higher-order approximate moments of the ratio of quadratic forms in the non-normal vector. The results for the normal case are then presented as a special case of this result. It is also indicated that the results for a large class of econometric estimators and test statistics can be obtained by using our general result.

This article considers a linear regression model in which misspecification relates to the use of a stochastic proxy variable. The analysis indicates the decline in efficiency of the predictions arising from the ordinary least squares and the Stein-rule estimation procedures when a proxy variable is used in the place of an unobservable variable. However, the performance of the Stein-rule predictions is still found to be better than the ordinary least squares predictions over a broad range of k, the characterizing scalar of the Stein-rule estimator.

The steady, fully developed, isothermal, incompressible laminar flow of power law fluids within a toroidal-type coiled tube has been studied for small ratio of tube radius to radius of curvature. Dean's constraint has been relaxed and the solutions of primary and secondary flows are obtained up to the second-order curvature ratio term. The expressions for primary and secondary flow of a Newtonian fluid are derived as special cases and are found to be in good agreement with published results. Comparison of the results with those of Newtonian fluids is made to bring out the effect of the power law index. The flow fields of dilatant and pseudoplastic fluids are found to differ significantly. The individual and collective roles played by the Reynolds number, curvature ratio, and power law index are discussed in detail. The results show that the flow rate of fluid in a curved tube is more influenced by curvature than by Reynolds number or power law index.

Significant improvement in properties is observed for filaments produced from blending of nylon 6/nylon 66 by melt spinning process. As-spun blend filaments show higher drawability due to wider crystal size distribution and interfacial slippage at the boundary between both components. This results in improved mechanical properties with tenacity of ∼ 1.0 GPa and initial modulus of ∼ 7.0 GPa. The improved tensile properties are associated with increased orientation, possible reduction in fibrillar size and formation of interconnected fibrillar network.

This article derives an unbiased estimator of the covariance matrix of the “mixed regression” estimator suggested by Theil and Goldberger for combining prior information with the sample information in regression analysis. This derivation facilitates the construction of finite-sample standard errors for the mixed estimators of the individual regression coefficients. Comparisons are made between the unbiased covariance estimator, the conventional consistent estimator based on the generalized least squares formula, and a simple modification of the latter, which is found to approximate the unbiased estimator well in practical situations.

A total of 331 male and 237 female individuals of the Ganga river prawn, Macrobrachium birmanicum choprai (TIWARI), were examined to establish relationship between its length and weight. The individuals of both the sexes were placed separately in different size groups. When plotted against corresponding values of weight, the average length computed for each size group exhibited an exponential relationship. However, the logarithimic values of observed lengths when plotted against corresponding values of weight exhibited a linear relationship. Correlation coefficient values for both the sexes were found highly significant (r = 0.9846 for males and 0.9762 for females).

Various new 2-(1'-acetyl-5'-substituted-aryl-2'-pyrazolin-3'-yl)aminopyridines (3a-3e) and 2-(1'-phenyl 5'-substituted aryl-2'-pyrazol-3'-yl)aminopyridines (4a-4e) have been derived from 2-(substituted benzylidenylacetyl)aminopyridines (2a-2e). The structure of these compounds have been elucidated by elemental and spectral (IR, 1 H-NMR, mass) analysis. Furthermore, above said compounds were evaluated for their insecticidal, antifangal, and antibacterial activities. Compound 4b 2-[1'-phenyl-5'-(o-chlorophenyl)2'-pyrazol-3'-yl]aminopyridine, when compared for insecticidal and antifungal activities with parathion and fluconazole, respectively, was found to be the most potent one in this series. It also possessed remarkable antibacterial properties.

Steroidogenic acute regulatory protein (StAR) is a 30 kDa mitochondrial protein that plays an essential role in steroid hormone biosynthesis by facilitating delivery of cholesterol across the mitochondrial membrane, where side chain cleavage occurs to initiate ovarian steroidogenesis. Because ethanol (EtOH) suppresses estradiol secretion in prepubertal female rats, we evaluated the effects of EtOH on prepubertal ovarian StAR.At 0700 hr, 28-day-old female rats were gavaged with saline or a 3 g/kg dose of EtOH. At 0800 hr, half of each of these two groups was treated with 15 IU of pregnant mare serum gonadotropin (PMSG). At 1000 hr, a 2 g/kg dose was administered to maintain moderately elevated blood alcohol levels. At 1600 hr, all of the animals were killed by decapitation, and blood and ovaries were collected for measurement of serum pregnenolone and estradiol and for ovarian StAR gene and protein expression.Northern blot analysis showed two major transcripts of 3.8 and 1.7 kb of ovarian StAR mRNA. The ovaries from EtOH-treated rats showed decreased (p0.01) basal expression of both 3.8 and 1.7 kb StAR transcripts. PMSG-stimulated animals showed a more than 4-fold increase (p0.001) in the levels of both transcripts, when compared with ovaries from animals that received saline or EtOH only. Conversely, in EtOH-treated animals, the PMSG-stimulated expression of the 1.7 kb transcript was blocked, and the increase in the 3.8 kb StAR transcript was blunted (p0.05 vs. PMSG). Western blot analysis revealed that EtOH exposure also depressed (p0.01) the basal expression of StAR protein. PMSG-stimulated animals showed an increase (p0.001) in levels of StAR protein, and this was blocked (p0.01) by EtOH. These changes observed in ovarian StAR mRNA and protein were paralleled by changes in serum pregnenolone and estradiol. Specifically, acute EtOH exposure suppressed (p0.05) the basal levels of both steroids. Furthermore, PMSG-stimulated animals showed an increase in the production of pregnenolone (p0.05) as well as estradiol (p0.01), and EtOH blocked this stimulatory action of PMSG on both steroids.These results demonstrate for the first time that EtOH is capable of altering ovarian StAR expression, which contributes to the detrimental effect this drug has on ovarian steroidogenesis during prepubertal development.

(2010). Indian Rivers Pollution—Critical Analysis: Ganga Action Plan. Indian Chemical Engineer: Vol. 52, No. 2, pp. 155-156.

(2010). Centuries Ago, A Hotter World. Indian Chemical Engineer: Vol. 52, No. 1, pp. 49-50.