Effect of Diluents on the Extraction of Mercury(II) by n-Butyl Acetate

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A novel Artificial Neural Network-based streamline tracing strategy applied to hypersonic waverider design

Streamline tracing in conical hypersonic flows is essential for designing high-performance waverider and intake. Conventionally, the streamline equations are solved after obtaining the velocity field from the solution of the axisymmetric conical flow field. The hypersonic waverider shape is generated from the base conical flow field by repeatedly applying the streamline tracing approach along several planes. When exploring the design space for optimization of the waverider, streamline tracing can be computationally expensive. We provide a novel strategy where first the Taylor-Maccoll equations for the inviscid axisymmetric conical flowfield and the streamlines from the shock are solved for a wide range of cone angle and Mach number conditions resulting in an extensive database. The streamlines are parametrized by a third-order polynomial, and an Artificial Neural Network (ANN) is trained to predict the coefficients of the polynomial for arbitrary inputs of Mach number, cone angle, and streamline originating location on the shock . We apply this strategy to design a cone derived waverider and compare the geometry obtained with the standard conical waverider design method and the simplified waverider design method. The ANN technique is highly accurate, with a difference of 0.68% with the standard in the coordinates of the waverider. RANS computations show that the ANN derived waverider does not indicate severe flow spillage at the leading edge, which is observed in the waverider generated from the simplified method. The new ANN-based approach is 20 times faster than the conventional method

Dynamics of Magnetized Bulk Viscous Strings in Brans-Dicke Gravity

We explore locally rotationally symmetric Bianchi I universe in Brans-Dicke gravity with self-interacting potential by using charged viscous cosmological string fluid. We use a relationship between the shear and expansion scalars and also take the power law for scalar field as well as self-interacting potential. It is found that the resulting universe model maintains its anisotropic nature at all times due to the proportionality relationship between expansion and shear scalars. The physical implications of this model are discussed by using different parameters and their graphs. We conclude that this model corresponds to an accelerated expanding universe for particular values of the parameters.Comment: 17 pages, 6 figure

Processing of Sorghum From Different Varieties and Hybrids for Semolina and Their Products

The present study was undertaken with the objective to standardise procedures for preparation of semolina (rava) from sorghum, to identify the best genotype for preparation of semolina and to study the nutritional quality parameters of semolina. For processing of sorghum, ten varieties and five hybrids were used for preparation of semolina and their products. A process has been standardized for semolina preparation using ultra grinding mill from sorghum grain. The semolina yield ranged from 46.51% to 54.29%. Hybrid CSH-15R gave the highest yield of semolina (54.29%). Starch content in semolina ranged from 59.93% to 66.43%. The new genotypes Phule Vasudha, Phule Yashoda and M 35-1 showed higher levels of starch content as compared to the other genotypes. The Phule Vasudha and Selection-3 showed higher levels of total soluble sugars in grains, as well as in semolina than the other genotypes. Phule Maulee gave higher level of crude fibre content (3.12%). The amino acid profile of sorghum grain and semolina showed very minor differences in the content due to the processing of sorghum grains into various products like semolina. The new genotypes of rabi sorghum showed comparable results for the mineral with that of hybrids. The organoleptic properties of the sweet (shira), upama and idali prepared from semolina were judged on the basis of colour, texture and appearance, flavour, taste and overall acceptability of the products using semi-trained judges and 1 to 9 hedonic scales. All products prepared from semolina were like very much and gave highest rating of more than 8 hedonic scales. While considering the yield of semolina from sorghum grains as well as their nutritional composition and organoleptic properties of the niche products (shira, upama, idali) prepared from them, the varieties Phule Vasudha and Phule Yashoda were the best one as compared to the other varieties and hybrids and overall varieties were better than the hybrids

Search for optical bursts from the gamma ray burst source GBS 0526-66

Attempts were made to detect optical bursts from the gamma-ray burst source GBS 0526-66 during Dec. 31, 1984 to Jan. 2, 1985 and Feb. 23 to Feb. 24, 1985, using the one meter reflector of the Kavalur Observatory. Jan. 1, 1985 coincided with the zero phase of the predicted 164 day period of burst activity from the source (Rothschild and Lingenfelter, 1984). A new optical burst photon counting system with adjustable trigger threshold was used in parallel with a high speed photometer for the observations. The best time resolution was 1 ms and maximum count rate capability was 255,000 counts s(-1). Details of the instrumentation and observational results are presented

Evaluation of the Anxiolytic Activity of NR-ANX-C (a Polyherbal Formulation) in Ethanol Withdrawal-Induced Anxiety Behavior in Rats

The present study investigates the anxiolytic activity of NR-ANX-C, a standardized polyherbal formulation containing the extracts of Withania somnifera, Ocimum sanctum, Camellia sinensis, Triphala, and Shilajit in ethanol withdrawal- (EW-) induced anxiety behavior in rats. Ethanol dependence in rats was produced by substitution of drinking water with 7.5% v/v alcohol for 10 days. Then, ethanol withdrawal was induced by replacing alcohol with drinking water, 12 hours prior to experimentation. After confirming induction of withdrawal symptoms in the alcohol deprived animals, the anxiolytic activity of the test compound in graded doses (10, 20, and 40 mg/kg) was compared to the standard drug alprazolam (0.08 mg/kg) in the elevated plus maze and bright and dark arena paradigms. In our study, single and repeated dose administration of NR-ANX-C reduced EW-induced anxiety in a dose-dependent manner. Even though the anxiolytic activity was not significant at lower doses, NR-ANX-C at the highest dose tested (40 mg/kg) produced significant anxiolytic activity that was comparable to the standard drug alprazolam. Based on our findings we believe that NR-ANX-C has the potential to be used as an alternative to benzodiazepines in the treatment of EW-induced anxiety

The contrasting features of Asian summer monsoon during surplus and deficient rainfall over India

An endeavour is made to distinguish the mean summer monsoon features during surplus and deficient monsoon seasons. Based on all-India summer monsoon rainfall, over 42 years (1958-99), seven surplus and ten deficient monsoon seasons are identified. Making use of daily averaged (00 Z and 12 Z) reanalysis data sets from the National Center for Environmental Prediction-National Center for Atmospheric Research for the corresponding surplus and deficient monsoon seasons, the mean circulation characteristics and large-scale energetics are examined. The circulation features denote that the cross equatorial flow, low-level jet and tropical easterly jet are stronger during a surplus monsoon. Further, strong Tibetan anticyclonic flow characterizes a surplus monsoon. The large-scale balances of kinetic energy, heat and moisture show a significantly large quantity of diabatic heating, adiabatic generation of kinetic energy, and horizontal convergence of heat and moisture during the surplus monsoon season compared with the deficient state. The regions with statistically significant difference between surplus and deficient monsoon seasons are delineated by a Student's t-test at the 95% confidence level. The remarkable aspect noticed in this study is that the Arabian Sea branch of the monsoon circulation is more vigorous during a surplus monsoon season, whereas the eastern Bay of Bengal branch is stronger during a deficient monsoon. The various large-scale budget terms of kinetic energy, heat and moisture are found to be consistent and in agreement with the seasonal monsoon activity over India

The Indian summer monsoon as revealed by the NCMRWF system

In this study, we present the mean seasonal features of the Indian summer monsoon circulation in the National Centre for Medium Range Weather Forecasting (NCMRWF) global data assimilation and forecast system. The large-scale budgets of heat and moisture are examined in the analyzed and model atmosphere. The daily operational analyses and forecasts (day 1 through day 5) produced for the summer seasons comprising June, July and August of 1995 and 1993 have been considered for the purpose. The principal aim of the study is two-fold. Primarily, to comprehend the influence of the systematic errors over the Indian summer monsoon, secondarily, to analyze the performance of the model in capturing the interseasonal variability. The heat and moisture balances show reduction in the influx of heat and moisture in the model forecasts compared to the analyzed atmosphere over the monsoon domain. Consequently, the diabatic heating also indicates reducing trend with increase in the forecast period. In effect, the strength of Indian summer monsoon, which essentially depends on these parameters, weakens considerably in the model forecasts. Despite producing feeble monsoon circulation, the model captures interseasonal variability realistically. Although, 1995 and 1993 are fairly normal monsoon seasons, the former received more rainfall compared to the latter in certain pockets of the monsoon domain. This is clearly indicated by the analyzed and model atmosphere in terms of energetics

Energy spectrum and the absolute flux of various celestial X-ray sources

The results on the flux of low energy X-rays in the range 2-18 Kev from Sco-X1, Tau-X1 and Cen-X2 celestial sources observed during two rocket flights, flown from the Thumba Equatorial Rocket Launching Station (TERLS), Trivandrum, India, are presented. The absolute flux and the energy spectrum obtained for these sources are compared with other similar observations. The results indicate a long-term exponential decrease in the energy flux of X-rays from Sco-X1 over the period 1965-1968. The X-ray source Cen-X2, which showed a remarkable outburst of X-rays in April 1967, had ceased to be active after May 1967. We present here the first evidence of the rediscovery of the low energy, X-ray flux from Cen-X2 since May 1967. These short-lived X-ray out-bursts may be attributed to a shock wave from the nova outburst expanding into the circumstellar medium

Bio-chemical basis in groundnut (Arachis hypogaea) resistant to leafminer (Aproaerema modicella)

A bio-chemical study was conducted to assess the role of different plant-chemical constituents using groundnut (Aeachis hypogaea L.) selections resistant ['ICG 5040','ICGS 2741','ICG (FDRS) 10','NC AC 17090' and 'GBPRS 312 (ICGV 86031),] and susceptible ('ICG 221', 'ICGS 44' and 'Robut 33-1 ') to leafminer [Aproaerema modicella (Deveuter)]. 'ICG 5040' and 'ICGS 2741' exuded more sap on 'injury than the other selections at 20 days after plant emergence under similar conditions. Bio-chemical analysis of complete plant-extracted sap at 50 days after plant emergence indicated that resistant selections particularly' ICG 5040' and 'GBPRS 312' contained higher quantities of soluble sugars, nitrogen (N) and polyphenols than the susceptible ones. Analysis of phenolic compouods of the sap samples through'high pressure liquid chromatography from top 2 open leaves 20 days aner plant emergence indicated that the concentration of these chemicals in the resistant selections was less than in the susceptible selection. However, resistant selections were able to exude more sap, compensating for the low concentration of phenolic compounds in the sa