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Simultaneous first order derivative spectrophotometric determination of vanadium and zirconium in alloy steels and minerals
A simple, selective and sensitive spectrophotometric method has been developed for the individual and simultaneous determination of trace amounts of vanadium(V) and zirconium(IV) in acetic acid medium using a newly synthesised reagent diacetylmonoxime salicyloylhydrazone (DMSH), without any prior separation. The molar absorptivity and Sandell's sensitivity of the coloured species are 1.30 x 10 4 and 1.82 x 10 4 Lmol -1cm -1 and 3.9 and 2.5 ng cm -2 for V(V) and Zr(IV), respectively. Beer's law is obeyed between 0.26-2.80 and 0.30-3.20 ?g mL -1 concentration of vanadium (V) and zirconium (IV) at 405 and 380 nm respectively. The stoichiometry of the complex was found to be 1:1 (metal:ligand) for V(V) and 1:2 for Zr(IV) complexes. These metal ions interfere with the determination of each other in zero order spectrophotometry. The first derivative spectra of these complexes permitted a simultaneous determination of V(V) and Zr(IV) at zero crossing wavelengths of 445 nm and 405 nm, respectively. The optimum conditions for maximum colour development and other analytical parameters were evaluated. The proposed method has been successfully applied for the determination of zirconium and vanadium in standard alloy steel samples, mineral and soil samples. 2012 Elsevier B.V. All rights reserved. -
Forecasting stock market volatility in India - Using linear and non - Linear models
Volatility models and their forecasting performance attracted the interest of many economic agents, especially for financial risk management. The role of economic agents is to decide which one will be best model for forecasting volatility. This paper examines the modeling and forecasting performance of BSE Sensex daily stock market returns over the period from 1 July 1997 to 31 October 2008, by using simple Random Walk, GARCH, EGARCH and TGARCH models. The out-of-sample forecasts are evaluated by using MAE, RMSE, MAPE and Theil - U Statistics. The result suggests the standardized residual of white noise series strongly rejects the null hypothesis for GARCH model and capture the serial dependence and inherent nonlinearity series. Moreover, Random walk model dominates the forecasting performance and it is considered as the best model followed by the TGARCH model. International Economic Society. -
Ultrasound assisted Friedel-Crafts acylation of aromatics using ferric sulphate as catalyst
The use of ultrasound in the acylation reactions of various aromatics and polyaromatics with different acyl chlorides, in the presence of catalytic amount of ferric sulphate at room temperature, gives good yields of the respective ketones with a short reaction time. A facile and simple synthesis of various aromatic ketones using Friedel-Crafts acylation has been established from the corresponding acid chlorides and aromatic or polyaromatic compounds, respectively under mild reaction conditions with shorter reaction times (30-45 min) and in reasonable yields. This method offers the advantage of low cost and ease of purification of the products because of the small amount of ferric sulphate used in these reactions. -
An efficient optimization based lung cancer pre-diagnosis system with aid of feed forward back propagation neural network (FFBNN)
World Health Organization (WHO) reports that worldwide 7.6 million deaths are caused by cancer each year. Uncontrollable cell development in the tissues of the lung is called as lung cancer. These uncontrollable cells restrict the growth of healthy lung tissues. If not treated, this growth can spread beyond the lung in the nearby tissue called metastasis and, form tumors. In order to preserve the life of the people who are suffered by the lung cancer disease, it should be pre-diagonized. So there is a need of pre diagnosis system for lung cancer disease which should provide better results. The proposed lung cancer prediagnosis technique is the combination of FFBNN and ABC. By using the Artificial Bee Colony (ABC) algorithm, the dimensionality of the dataset is reduced in order to reduce the computation complexity. Then the risk factors and the symptoms from the dimensional reduced dataset are given to the FFBNN to accomplish the training process. In order to get higher accuracy in the prediagnosis process, the FFBNN parameters are optimized using ABC algorithm. In the testing process, more data are given to well trained FFBNN-ABC to validate whether the given testing data predict the lung disease perfectly or not. 2005-2013 JATIT & LLS.All rights reserved. -
2-(6-Chloro-2,3,4,9-tetrahydro-1H-carbazol-1-yl-idene)propanedinitrile
The molecular conformation of the title compound, C15H 10ClN3, is stabilized by an intramolecular N-H?N hydrogen bond with an S(7) ring motif. The crystal packing is controlled by N-H?N and C-H?N intermolecular interactions. One of the methylene groups of the cyclohexene ring is disordered over two positions with refined occupancies of 0.457 (12) and 0.543 (12). -
Managing workplace diversity: Issues and challenges
Diversity management is a process intended to create and maintain a positive work environment where the similarities and differences of individuals are valued. The literature on diversity management has mostly emphasized on organization culture; its impact on diversity openness; human resource management practices; institutional environments and organizational contexts to diversity-related pressures, expectations, requirements, and incentives; perceived practices and organizational outcomes related to managing employee diversity; and several other issues. The current study examines the potential barriers to workplace diversity and suggests strategies to enhance workplace diversity and inclusiveness. It is based on a survey of 300 IT employees. The study concludes that successfully managing diversity can lead to more committed, better satisfied, better performing employees and potentially better financial performance for an organization. The Author(s) 2012. -
An empirical investigation of foreign direct investment and economic growth in SAARC nations
Purpose This paper aims to investigate the causal nexus between foreign direct investment (FDI) and economic growth in SAARC countries. Design/methodology/approach Johansen's cointegration test was employed to examine the long?run relationship between foreign direct investment and economic growth in SAARC countries. Besides, the vector error correction model (VECM) was employed to examine the causal nexus between foreign direct investment and economic growth in SAARC countries for the years 1970?2007. Finally, the impulse response function (IRF) has been employed to investigate the time paths of log of foreign direct investment (LFDI) in response to one?unit shock to the log of gross domestic product (LGDP) and vice versa. Findings The Johansen cointegration result establishes a long?run relationship between foreign direct investment and gross domestic product (GDP) for the sample of SAARC nations, namely, Bangladesh, India, Maldives, Nepal, Pakistan and Sri Lanka. The empirical results of the vector error correction model exhibit a long?run bidirectional causal link between GDP and FDI for the selected SAARC nations except India. The test results show that there is a one?way long?run causal link from GDP to FDI for India. Research limitations/implications This paper employed annual data to examine the causal nexus between FDI and economic growth. Therefore, researchers are encouraged to test the FDI?growth relationship further by using quarterly data. Practical implications The SAARC nations should adopt effective policy measures that would substantially enlarge and diversify their economic base, improve local skills and build up a stock of human capital recourses capabilities, enhance economic stability and liberalise their market in order to attract as well as benefit from long?term FDI inflows. Originality/value This paper would be immensely helpful to the policy makers of SAARC countries to plan their FDI policies in a way that would enhance growth and development of their respective economies. 2011, Emerald Group Publishing Limited -
Crystal structures of 1,7-bis(furyl)-4-(1,3-dithiolan-2-ylidene)-1, 6-heptadiene-3,5-dione and 1,7-bis(thienyl)-4-(1,3-dithiolan- 2-ylidene)-1,6-heptadiene-3,5-dione
The title compounds (bis(alkenoyl) ketene dithioacetals) were prepared starting from the cyclic acyl ketene dithioacetal and aromatic aldehydes. These compounds were characterized by IR, 1H NMR, mass spectral studies and X-ray crystal structure analysis. The bis(furyl) ketene dithioacetal crystallized in the space group P1? with unit cell dimensions a = 7.7626(12) , b = 9.0217(13) , c = 26.827(5) , ? = 86.271(14), ? = 87.643(14), ? = 66.286(11) and the structure was refined to an R-factor of 0.0528 while bis(thienyl) ketene dithioacetal crystallized in the space group P21/c with unit cell dimensions a = 10.2433(9) , b = 10.4142(6) , c = 18.0973(18) , ? = 106.0 and the structure was refined to an R-factor of 0.0446. The ketenedithioacetal functionality present between the carbonyl groups prevents the possibility of keto-enol tautomerization in these compounds. In both the crystal structures, the crystal packing is stabilized by C-H?O hydrogen bonds as well as van der Waals interactions. Springer Science+Business Media, LLC 2011. -
The response of guide dogs and pet dogs (canis familiaris) to cues of human referential communication (pointing and gaze)
The study raises the question of whether guide dogs and pet dogs are expected to differ in response to cues of referential communication given by their owners; especially since guide dogs grow up among sighted humans, and while living with their blind owners, they still have interactions with several sighted people. Guide dogs and pet dogs were required to respond to point, point and gaze, gaze and control cues of referential communication given by their owners. Results indicate that the two groups of dogs do not differ from each other, revealing that the visual status of the owner is not a factor in the use of cues of referential communication. Both groups of dogs have higher frequencies of performance and faster latencies for the point and the point and gaze cues as compared to gaze cue only. However, responses to control cues are below chance performance for the guide dogs, whereas the pet dogs perform at chance. The below chance performance of the guide dogs may be explained by a tendency among them to go and stand by the owner. The study indicates that both groups of dogs respond similarly in normal daily dyadic interaction with their owners and the lower comprehension of the human gaze may be a less salient cue among dogs in comparison to the pointing gesture. 2008 Springer-Verlag. -
Novel algorithm for control of a shunt active power filter based on a three-level voltage source inverter
A three-level voltage source inverter is utilized to implement a shunt active power filter. SVPWM technique is used in the control circuit to generate the required gate pulses for the voltage source inverter. Principle of operation and analysis of the control circuit is presented. The proposed control algorithm ensures balance of dc bus voltages. Hence this active power filter is ideally suited for high power drives and transmission systems. The simulation results are presented and analyzed. The THD of load current is reduced to 6.47 % from 28.795 % in steady operation. 2010 Institute of Thermomechanics AS CR. -
Growth and microindentation analysis of pure and doped Sb2 Se3 crystals
Pure and doped antimony selenide (Sb2 Se3, Sb 2 Se2.8 Te0.2, and Sb2 Se 2.6 Te0.4) crystals have been grown from melt by the Bridgman Stockbarger method. X-ray powder diffraction analysis was carried out to determine the lattice parameters of the grown samples. The morphology of cleavage planes was observed using SEM. Energy dispersive analysis by X-rays (EDAX) was done to find out the chemical composition of the grown samples. Correlation of microhardness with other mechanical characteristics such as toughness, brittleness, and yield strength, has been investigated. The effects of Te doping on the mechanical behaviour and energy gap were also studied on the cleavage faces. Ti?tak. -
Alpha decay favoured isotopes of some superheavy nuclei: Spontaneous fission versus alpha decay
Spontaneous fission and alpha decay are the main decay modes for superheavy nuclei. The superheavy nuclei which have small alpha decay half-life compared to spontaneous fission half-life will survive fission and can be detected in the laboratory through alpha decay. We have studied the alpha decay half-life and spontaneous half-life of some superheavy elements in the atomic range Z = 100-130. Spontaneous fission half-lives of superheavy nuclei have been calculated using the phenomenological formula and the alpha decay half-lives using Viola-Seaborg-Sobiczewski formula (Sobiczewski et al. 1989), semi empirical relation of Brown (1992) and formula based on generalized liquid drop model proposed by Dasgupta-Schubert and Reyes (2007). The results are reported here. -
Photometric identification of objects from galaxy evolution explorer survey and sloan digital sky survey
We have used Galaxy Evolution Explorer (GALEX) and Sloan Digital Sky Survey (SDSS) observations to extract seven band photometric magnitudes for over 80 000 objects in the vicinity of the North Galactic Pole. Although these had been identified as stars by the SDSS pipeline, we found through fitting with model spectral energy distributions that most were, in fact, of extragalactic origin. Only about 9 per cent of these objects turned out to be mainsequence stars and about 11 per cent were white dwarfs and red giants collectively, while galaxies and quasars contributed to the remaining 80 per cent of the data. We have classified these objects into different spectral types (for the stars) and into different galactic types (for the galaxies). As part of our fitting procedure, we derive the distance and extinction to each object and the photometric redshift towards galaxies and quasars. This method easily allows for the addition of any number of observations to cover a more diverse range of wavelengths, as well as the addition of any number of model templates. The primary objective of this work is to eventually derive a three-dimensional extinction map of the Milky Way Galaxy. 2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. -
An iconic turn in philosophy
[No abstract available] -
Bio-demineralization of Indian bituminous coal by Aspergillus niger and characterization of the products
The effect of demineralization on an Indian bituminous coal has been investigated by filamentous fungus Aspergillus niger. X-ray diffraction profile reveals the presence of inorganic components in the sample. Bio-Solubilization using Aspergillus niger significantly reduced the ash content in the coal sample (10.23wt% to 5.21wt %). Leaching process removed silicate and pyrite minerals where as aluminates were decreased considerably. The carbon content showed an increase of 19.94% where as the oxygen content decreased by 52.3%. During biosolubilization the fungus produced acids like gluconic acid, oxalic acid and citric acid along with oxalates which are responsible for the demineralization in coal by the formation of mineral salts. The broad diffraction peak at 2?~25.5 is due to the crystalline carbon in the sample which is mainly due to the typical (002) plane reflection of graphite. -
Monopsonistic exploitation in contract farming: Articulating a strategy for grower cooperation
Contract farming has been considered a new hope to instil dynamism in third world agriculture. However, there remains serious concern whether small peasants will be able to benefit from this system since buyers may often be a single large or at most, few large corporations, a typical case of monopsony. In this paper we question the basis of the fears that are often raised in the literature. A clear analytical approach to understanding the (economic) meaning of monopsony helps us articulate a strategy for grower cooperation that could effectively deal with monopsony power in contract farming systems. Copyright 2007 John Wiley & Sons, Ltd. -
A compilation of interstellar column densities
We have collated absorption line data toward 3008 stars in order to create a unified database of interstellar column densities. These data have been taken from a number of different published sources and include many different species and ionizations. The preliminary results from our analysis show a tight relation [N(H)/E(B - V)= 6.1210 21] between N(H) and E(B - V). Similar plots have been obtained with many different species, and their correlations along with the correlation coefficients are presented. 2012 The American Astronomical Society. All rights reserved. -
Indias roadmap of convergence to international financial reporting standards (IFRS)
[No abstract available] -
Novel heterocyclic thiosemicarbazones derivatives as colorimetric and "turn on" fluorescent sensors for fluoride anion sensing employing hydrogen bonding
(Chemical Equation Presented) Two novel heterocyclic thiosemicarbazone derivatives have been synthesized, and characterized, by means of spectroscopic and single crystal X-ray diffraction methods. Their chromophoric-fluorogenic response towards anions in competing solvent dimethyl sulfoxide (DMSO) was studied. The receptor shows selective recognition towards fluoride anion. The binding affinity of the receptors with fluoride anion was calculated using UV-visible and fluorescence spectroscopic techniques. 2013 Elsevier B.V. All rights reserved.