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Synthesis, characterization and biological activity studies on 6-p-dimethylaminophenyl-5,6-dihydrobenzoimidazo [1,2-c]quinazoline: Crystal structure of the title compound and comparative study with related derivatives
Reaction of o-aminophenylbenzimidazole with p-dimethylaminobenzaldehyde yielded 6-p-dimethylamin-ophenyl-5,6-dihydrobenzoimidazo[ 1,2-c]quinazoline, which was characterized by elemental analysis, IR, UV-Vis, 1H NMR, 13C NMR, mass spectral studies and X-ray crystal structure analysis. Studies on the antimicrobial activity of the compound revealed that it is active against fungus Yeast but not Bacillus subtilis. The compound crystallized in the space group P2 1/n with the unit cell parameters a = 10.652(2) b = 11.002(2) c = 15.753(2) ? = 109.29(2) and the structure was refined to an R-factor of 0.0479. The hydropyrimidine ring in the quinazoline moiety is in skew-boat conformation. The dimethylamino group attached to phenyl ring is in conjugation with it. The structure was stabilized by intermolecular C-H-N interactions. A few of the related quinazolines (6-p-hydroxyphenyl-5,6-dihydrobenzoimidazo [1,2-c]quinazoline; 6-phenyl-5,6-dihydrobenzoimidazo[1,2-c]quinazoline; 6-pyridyl-5,6- dihydrobenzoimidazo[1,2-c]quinazoline; 6-furyl-5,6-dihydrobenzoimidazo[1,2-c] quinazoline) were also examined for their biological activity, in addition to their characterization by IR, UV-Vis, JH and 13C NMR spectral studies along with structural comparison. Springer Science+Business Media, LLC 2011. -
Decomposition of graphs into induced paths and cycles
A decomposition of a graph G is a collection ? of subgraphs H1,H2,..., Hr of G such that every edge of G belongs to exactly one Hi. If each Hi is either an induced path or an induced cycle in G, then ? is called an induced path decomposition of G. The minimum cardinality of an induced path decomposition of G is called the induced path decomposition number of G and is denoted by ?i(G). In this paper we initiate a study of this parameter. -
A new optimal design and analysis method based on MADM for MEMS products development
Abstract This paper presents an optimum design method to support the total micro-electromechanical systems (MEMS) product/device optimization, and its evaluation at the conceptual stage itself using the multiple attribute decision making method. In the traditional MEMS product development cycle, simulation and design using software tools are very important due to the knowledge limitation and complexity in design, fabrication, and packaging processes. The available tools are time consuming and relay on trial and error to achieve an optimum solution. The proposed method simplifies the relationship between parameters of design, fabrication, materials, packaging, and the performance of the MEMS product. The methodology is explained with the help of design flow diagram and time chart. A MEMS-based radio frequency (RF) power sensor is designed and the methodology is demonstrated. The proposed sensitivity analysis method is more effective and less time consuming than traditional techniques. Sensitivity analysis is carried out by varying the thickness of the signal conductor. The results of RF power sensor with insertion loss 0.428 dB, reflection loss 25.956 and voltage standing wave ratio of 1.106 at 1.5 GHz are reported. Springer-Verlag London Limited 2012. -
The dharma of Kama: Kamasra's morality of integrated Purusartha
[No abstract available] -
Synthesis and crystal structure of 1,7-bis(4-methoxyphenyl)-4-(1,3- dithiolan-2-ylidene)-1,6-heptadiene-3,5-dione
The synthesis and crystal structure of 1,7-bis(4-methoxyphenyl)-4-(1,3- dithiolan-2-ylidene)-1,6-heptadiene-3,5-dione is described. This compound crystallizes in the space group P21 with unit cell parameters a = 14.207 b = 7.752(1) c = 19.473(1) ? = 91.00(3), with two molecules in the asymmetric unit. The ketenedithioacetal functionality present between the carbonyl groups prevents the possibility of keto-enol tautomerization in this compound. The cinnamoyl groups are organized parallel to each other due to the push-pull nature of the ketenedithioacetal functionality. 2010 Springer Science+Business Media, LLC. -
Eco friendly nitration of toluene using modified zirconia
Nitration of toluene has been studied in the liquid phase over a series of modified zirconia catalysts. Zirconia, zirconia- ceria (Zr0.98Ce0.02)O2, sulfated zirconia and sulfated zirconia- ceria were synthesised by co precipitation method and were characterised by X-ray diffraction, BET surface area, Infra red spectroscopy analysis (FTIR), Thermogravimetric analysis (TGA), Scanning Electron Microscopy (SEM), and Energy Dispersive X ray analysis (EDAX). The acidity of the prepared catalysts was determined by FTIR pyridine adsorption study. X-ray diffraction studies reveal that the catalysts prepared mainly consist of tetragonal phase with the crystallite size in the nano range and the tetragonal phase of zirconia is stabilized by the addition of ceria. The modified zirconia samples have higher surface area and exhibits uniform pore size distribution aggregated by zirconia nanoparticles. The onset of sulfate decomposition was observed around 723 K for sulfated samples. The catalytic performance was determined for the liquid phase nitration of toluene to ortho-, meta- and para- nitro toluene. The effect of reaction temperature, concentration of nitric acid, catalyst reusability and reaction time was also investigated. 2013 BCREC UNDIP. -
Leaching of minerals in subbituminous Indian coal and characterisation of the products by SEM
Coal is chemically and physically a complex and heterogeneous material, consisting of organic and inorganic mineral constituents. Presence of minerals in excess will pollute water, air and soil. Concerted efforts are needed to reduce 'ash forming' inorganic elements and to develop clean methods of using coal. This paper reports the demineralization of sub bituminous coal with EDTA, HCl, HF, chloroform and acid mixture. The residual coal from each treatment was analyzed using Scanning Electron Microscopy (SEM) and Ultimate analysis. All the micrographs were bright field and revealed several features corresponding to the mineral grains. It comprised of lithophiles like aluminium, silicates and calcium. The absences of some morphological features correspond to inorganic elements in residual coal samples confirming 'demineralization'. This result was further confirmed with the CHNS analysis. It was evident from the results that amongst the leachants used, Hydrofluoric acid and acid mixture had significant effect in removing the mineral matter, sulphur and oxygenated functional groups. Global Science Publications. -
Low cost calibrated mechanical noisemaker for hearing screening of neonates in resource constrained settings
Background & objectives: There is a need to develop an affordable and reliable tool for hearing screening of neonates in resource constrained, medically underserved areas of developing nations. This study valuates a strategy of health worker based screening of neonates using a low cost mechanical calibrated noisemaker followed up with parental monitoring of age appropriate auditory milestones for detecting severe-profound hearing impairment in infants by 6 months of age. Methods: A trained health worker under the supervision of a qualified audiologist screened 425 neonates of whom 20 had confirmed severe-profound hearing impairment. Mechanical calibrated noisemakers of 50, 60, 70 and 80 dB (A) were used to elicit the behavioural responses. The parents of screened neonates were instructed to monitor the normal language and auditory milestones till 6 months of age. This strategy was validated against the reference standard consisting of a battery of tests - namely, auditory brain stem response (ABR), otoacoustic emissions (OAE) and behavioural assessment at 2 years of age. Bayesian prevalence weighted measures of screening were calculated. Results: The sensitivity and specificity was high with least false positive referrals for 70 and 80 dB (A) noisemakers. All the noisemakers had 100 per cent negative predictive value. 70 and 80 dB (A) noisemakers had high positive likelihood ratios of 19 and 34, respectively. The probability differences for pre- and post- test positive was 43 and 58 for 70 and 80 dB (A) noisemakers, respectively. Interpretation & conclusions: In a controlled setting, health workers with primary education can be trained to use a mechanical calibrated noisemaker made of locally available material to reliably screen for severe-profound hearing loss in neonates. The monitoring of auditory responses could be done by informed parents. Multi-centre field trials of this strategy need to be carried out to examine the feasibility of community health care workers using it in resource constrained settings of developing nations to implement an effective national neonatal hearing screening programme. -
Quantum tasks using six qubit cluster states
The usefulness of the recent experimentally realized six photon cluster state by C. Y. Lu et al. (Nature 3:91, 2007) is investigated for quantum communication protocols like quantum teleportation and quantum information splitting (QIS) and dense coding. We show that the present state can be used for the teleportation of an arbitrary two qubit state deterministically. Later, we devise two distinct protocols for the QIS of an arbitrary two qubit state among two parties. We construct sixteen orthogonal measurement basis on the cluster state, which will lock an arbitrary two qubit state among two parties. The capability of the state for dense coding is investigated and it is shown that one can send five classical bits by sending only three qubits using this state as a shared entangled resource.We finally show that this state can also be utilised in the remote state preparation of an arbitrary two qubit state. Springer Science+Business Media, LLC 2010. -
Neuro-technology and counselling
[No abstract available] -
Crystal structure of 1,7-bis(4-chlorophenyl)-4-(1,3-dithiolan-2-ylidene)-1, 6-heptadiene-3,5-dione
The synthesis and crystal structure of 1,7-bis(4-chlorophenyl)-4-(1,3- dithiolan-2-ylidene)-1,6-heptadiene-3,5-dione is described. This compound is a curcuminoid analogue, configurationally symmetric about the C4-C5 atoms and also retains the two fold axis in the crystal phase. This compound crystallizes in the space group C2/c with unit cell parameters a = 19.203(1) b = 13.147(1) c = 8.801(1) ? = 112.99(1), with half a molecule in the asymmetric unit. The ketenedithioacetal functionality present between the carbonyl groups prevents the possibility of keto-enol tautomerization in this compound. The push-pull nature of the ketenedithioacetal functionality organizes the cinnamoyl groups parallel to each other. 2008 Springer Science+Business Media, LLC. -
Induced acyclic path decomposition in graphs
A decomposition of a graph G is a collection ? of graphs H1, H2,...,Hr of G such that every edge of G belongs to exactly one Hi. If each Hi is either an induced path in G, then ? is called an induced acyclic path decomposition of G and if each Hi is a (induced) cycle in G then ? is called a (induced) cycle decomposition of G. The minimum cardinality of an induced acyclic path decomposition of G is called the induced acyclic path decomposition number of G and is denoted by ?ia(G). Similarly the cyclic decomposition number ?c(G) is defined. In this paper we begin an investigation of these parameters. -
Exchange rate volatility and export growth in India: An ARDL bounds testing approach
This paper empirically investigates the impact of exchange rate volatility on the real exports in India using the ARDL bounds testing procedure proposed by Pesaran et al. (2001). Using annual time series data, the empirical analyses has been carried out for the period 1970 to 2011. The study results confirm that real exports are cointegrated with exchange rate volatility, real exchange rate, gross domestic product and foreign economic activity. Our findings indicate that the exchange rate volatility has significant negative impact on real exports both in the short-run and long-run, implying that higher exchange rate fluctuation tends to reduce real exports in India. Besides, the real exchange rate has negative short-run and positive long-run effects on real exports. The empirical results reveal that GDP has a positive and significant impact on India's real exports in the long-run, but the impact turns out to be insignificant in the short-run. In addition, the foreign economic activity exerts significant negative and positive impact on real exports in the short-run and long-run, respectively. 2013 Growing Science Ltd. All rights reserved. -
Isolation and Characterization of Antidermatophytic Bioactive Molecules from Piper longum L. Leaves
Piper longum L. (Piperaceae) commonly known as "long pepper" is a well known medicinal plant in ayurveda. Different parts of this plant, such as root, seed, fruit, whole plant etc. are used traditionally in various ailments. Here we have investigated the antidermatophytic activity of sequentially extracted petroleum ether, chloroform, methanol and water extracts from P. longum leaf against Trichophytonmentagrophytes, T. rubrum, T. tonsurans, Microsporum fulvum and M. gypseum. Better activity of chloroform and methanol extracts was observed. The chloroform extract was selected for further study and the MIC value was recorded as 5.0 mg ml-1 against the test organisms. In the chloroform extract, tannins and phenolic compounds were detected. Further activity-guided fractionation of chloroform extract by silica gel column chromatography yielded nine major fractions. Among these, fraction-1, 4, 5 and 7 showed higher antidermatophytic activity. Fraction-4 on further purification by repeated column chromatography yielded a potential antidermatophytic fraction showing MIC value of 0.625 mg ml-1 against T. mentagrophytes and T. rubrum as determined by broth microdilution method. The major compounds were identified as 1,2-benzenedicarboxylic acid, bis(2-ethylhexyl) ester (C24H38O4] (41.45 %), 2,2-dimethoxybutane (C6H14O2] (13.6 %) and ?-myrcene (C10H16) (6.75 %) based on GC-MS data. 2012 Association of Microbiologists of India. -
Further results on induced graphoidal decomposition
Let G be a nontrivial, simple, finite, connected and undirected graph. A graphoidal decomposition (GD) of G is a collection ? of paths and cycles in G that are internally disjoint such that every edge of G lies in exactly one member of ?. As a variation of GD the notion of induced graphoidal decomposition (IGD) was introduced in [S. Arumugam, Path covers in graphs (2006)] which is a GD all of whose members are either induced paths or induced cycles. The minimum number of elements in such a decomposition of a graph G is called the IGD number, denoted by ?i(G). In this paper, we extend the study of the parameter ?i by establishing bounds for ?i(G) in terms of the diameter, girth and the maximum degree along with characterization of graphs achieving the bounds. 2013 World Scientific Publishing Company. -
The peculiar radio-loud narrow line Seyfert 1 galaxy 1H 0323+342
We present a multiwavelength study of the radio-loud narrow-line Seyfert 1 galaxy (NLSy1) 1H 0323+342, detected by the Fermi Gamma-Ray Space Telescope. Multiband light curves show many orphan X-ray and optical flares having no corresponding ?-ray counterparts. Such anomalous variability behavior can be due to different locations of the emission region from the central source. During a large flare, a ?-ray flux doubling timescale as small as ?3 hr is noticed. We built spectral energy distributions (SEDs) during different activity states and modeled them using a one-zone leptonic model. The shape of the optical/UV component of the SEDs is dominated by accretion disk emission in all the activity states. In the X-ray band, significant thermal emission from the hot corona is inferred during quiescent and first flaring states; however, during subsequent flares, the nonthermal jet component dominates. The ?-ray emission in all the states can be well explained by inverse-Compton scattering of accretion disk photons reprocessed by the broad-line region. The source showed violent intra-night optical variability, coinciding with one of the high ?-ray activity states. An analysis of the overall X-ray spectrum fitted with an absorbed power-law plus relativistic reflection component hints at the presence of an Fe K? line and returns a high black hole spin value of a = 0.96 0.14. We argue that 1H 0323+342 possesses dual characteristics, akin to both flat-spectrum radio quasars (FSRQs) and radio-quiet NLSy1 galaxies, though at a low jet power regime compared to powerful FSRQs. 2014. The American Astronomical Society. All rights reserved. -
Chemical leaching of an indian bituminous coal and characterization of the products by spectroscopic techniques
Fourier transform infrared (FTIR) spectra of high volatile bituminous coal as well as their insoluble organic matter, obtained by chemical leaching with HF, EDTA and acid mixture (HF + HCl and HF + HNO3) were recorded between 500 and 4000 cm-1. UV-Visible-NIR spectroscopy was used to study the sample and its leached products in the 200-800 nm wavelength region. Oxygen containing structures were observed in the 1800-1000 cm-1 zone, aliphatic hydrogen in the 2920-2800 cm-1 zone, aromatic outof- plane structure in the 900-670 cm-1 zone. A great abundance of C=C structure was noticed at 1600 cm-1 region, while clay and silicate minerals were identified in the 540 cm-1 and 1030 cm-1 region. With chemical leaching silicate bands showed a decrease in intensity and were least for EDTA and HF leached samples. The UV-Visible -NIR spectrum showed absorption maximum at 235-270 nm and was shown a red shift with leaching. The II-II* electronic transitions of the poly-nuclear aromatic hydrocarbons was responsible for the absorption at 680 nm. The weak bands observed in the visible region (400-500 nm) were due to the presence of SO2 in the sample and decreased with chemical leaching. It was evident from the results that amongst the leachants used, hydrofluoric acid and acid mixture had significant effect in removing the mineral matter and oxygenated functional groups. -
Systematic investigations of graphene layers in sub-bituminous coal
Coal is the plentiful and widely and universally used fuel. However, its structural characteristic makes a perception that it is only worthwhile for generating energy via combustion. Herein we report a simple method to synthesize nanometre-sized graphene sheets with amorphous carbon addends on the edges from sub-bituminous coal. The X-ray analysis reveals the presence of crystalline carbon in the amorphous background. The average number of carbon atoms and aromatic layers was estimated as ?21 and 8. The interlayer spacing d 002 for the aromatic lamellae of samples leached using HF and acetic acid, are found to be 0.352 and 0.376 nm, respectively. The oxidation of coal structure resulted in nanometre sized graphene having lateral size of 4.19 nm and stacking height of 2.3 nm. The Raman spectrum analysis confirmed the formation of finite sized, less defective graphene nanolayers with leaching. The crystalline carbon within the coal matrix displaced with chemical leaching, resulting nano-meter sized graphene sheets. The results also established that with HF leaching, carbon in coal becomes more stacked and ordered compared to organic acid leached coal. 2014 Pleiades Publishing, Ltd. -
Crude oil prediction using a hybrid radial basis function network
In the recent years, the crude oil is one of the most important commodities worldwide. This paper discusses the prediction of crude oil using artificial neural networks techniques. The research data used in this study is from 1st Jan 2000- 31st April 2014. Normally, Crude oil is related with other commodities. Hence, in this study, the commodities like historical datas of gold prices, Standard & Poors 500 stock index (S & P 500) index and foreign exchange rate are considered as inputs for the network. A radial basis function is better than the back propagation network in terms of classification and learning speed. When creating a radial basis functions, the factors like number of radial basis neurons, radial layers spread constant are taken into an account. The spread constant is determined using a bio inspired particle swarm optimization algorithm. A hybrid Radial Basis Function is proposed for forecasting the crude oil prices. The accuracy measures like Mean Square Error, Mean Absolute Error, Sum Square Error and Root Mean Square Error are used to access the performance. From the results, it is clear that hybrid radial basis function outperforms the other models. 2005 - 2015 JATIT & LLS. All rights reserved.