Showing papers by "Indian Institute of Technology Kharagpur published in 2004"
TL;DR: The role of polymers as gas sensors, pH sensors, ion-selective sensors, humidity sensors, biosensor devices, etc., are reviewed and discussed in this article, and current trends in sensor research and also challenges in future sensor research are discussed.
1,126 citations
TL;DR: In this article, the results of investigations carried out in studying the fuel properties of karanja methyl ester (KME) and its blend with diesel from 20% to 80% by volume and in running a diesel engine with these fuels.
Abstract: This paper presents the results of investigations carried out in studying the fuel properties of karanja methyl ester (KME) and its blend with diesel from 20% to 80% by volume and in running a diesel engine with these fuels. Engine tests have been carried out with the aim of obtaining comparative measures of torque, power, specific fuel consumption and emissions such as CO, smoke density and NOx to evaluate and compute the behaviour of the diesel engine running on the above-mentioned fuels. The reduction in exhaust emissions together with increase in torque, brake power, brake thermal efficiency and reduction in brake-specific fuel consumption made the blends of karanja esterified oil (B20 and B40) a suitable alternative fuel for diesel and could help in controlling air pollution.
605 citations
TL;DR: In this paper, carboxymethyl cellulose-g-polyacrylamide was synthesized by a ceric ion induced solution polymerization technique by varying the amount of catalyst and monomer, six different grades of graft copolymers were synthesized.
503 citations
TL;DR: In this article, the catalytic activity of the Pt-Ni bi-MNPs has been found to be superior to the activities of monometallic Pt nanoparticles, which could be attributed to the electronic effect and the segregation behavior of the material in the alloy.
Abstract: Bimetallic Pt–Ni nanoparticles (bi-MNPs) have been prepared at room temperature by a wet chemical technique from a micellar solution containing the corresponding metal salts. Co-reduction of the salts produced alloyed particles in bulk quantity. Use of different ratios of the respective metal salts supported the synthesis of tunable compositions of the Pt–Ni alloys. These alloyed bi-MNPs of variable compositions were exploited to study their catalytic activities towards the reduction of aromatic nitro compounds. The kinetics of the reduction was monitored under different experimental conditions. The catalytic activity of the Pt–Ni bi-MNPs has been found to be superior to the activities of monometallic Pt nanoparticles. Moreover, it was found that the rate of reduction of nitroaromatics is sensitive to the composition of the alloy catalysts. This could be attributed to the electronic effect and the segregation behavior of the material in the alloy.
455 citations
TL;DR: In this paper, a transcritical carbon dioxide heat pump system has been investigated and a computer code has been developed to obtain sub-critical and super-critical thermodynamic and transport properties of carbon dioxide.
Abstract: Energetic and exergetic analyses as well as optimization studies of a transcritical carbon dioxide heat pump system are presented in this article. A computer code has been developed to obtain sub-critical and super-critical thermodynamic and transport properties of carbon dioxide. Estimates for irreversibilities of individual components of the system lead to possible measures for performance improvement. The COP trends indicate that such a system is more suitable for high heating end temperatures and modest cold end temperatures. Expressions for optimum cycle parameters have been developed and these correlations offer useful guidelines for optimal system design and for selecting appropriate operating conditions.
350 citations
TL;DR: From the results it is possible to observe that electrophilicity index may be suitable to effectively describe the biological activity.
340 citations
TL;DR: In this paper, a two-phase extraction of AuCl4- followed by its reduction with sodium borohydride in the presence of the surfactant, CPC, was exploited to examine their optical properties when exposed to various solvent systems and ligands by measuring the changes in localized surface plasmon resonance (LSPR) spectrum.
Abstract: Cetylpyridinium chloride(CPC)-stabilized gold organosol in toluene has been prepared by using a two-phase (water−toluene) extraction of AuCl4- followed by its reduction with sodium borohydride in the presence of the surfactant, CPC. The surfactant-stabilized gold nanoparticles were exploited to examine their optical properties when exposed to various solvent systems and ligands by measuring the changes in the localized surface plasmon resonance (LSPR) spectrum. It was seen that the position of the surface plasmon band of metal nanoparticles is greatly influenced by the solvents and the ligands under consideration. The surface plasmon absorption maxima modulates/varies between 520 and 550 nm for gold nanoparticles, depending on the refractive index of the solvent. The significant discovery presented here is that λmax of the LSPR shifts to the blue by 3 nm for the increase of one carbon atom in the alcohol chain. Cationic and anionic surfactants of different chain lengths induce changes in the optical prope...
337 citations
TL;DR: In this paper, the rheological properties of two varieties of rice with Hydroxy propyl methyl cellulose (HPMC) added as gluten substitute were studied using a farinograph and a rheometer and compared with wheat dough to find its suitability for making rice bread.
319 citations
Bradley University1, Pontifical Catholic University of Chile2, University of Tartu3, University of Louisville4, University of Latvia5, University of New Mexico6, Slovak Academy of Sciences7, University of San Carlos8, University of Malta9, Ghent University10, Clemson University11, University of Buenos Aires12, Osaka University13, Illinois State University14, National Autonomous University of Mexico15, University of Brasília16, University of Western Australia17, University of Lima18, Boğaziçi University19, University of Kassel20, University of York21, University of Queensland22, Åbo Akademi University23, Al Akhawayn University24, Indian Institute of Technology Kharagpur25, University of Hawaii at Manoa26, University of Catania27, University of Otago28, University of Dhaka29, Chemnitz University of Technology30, Knox College31, Comenius University in Bratislava32, University of Rijeka33, University of Malaya34, Vilnius University35, American University of Beirut36, Kwangju Health College37, University of Salzburg38, Utrecht University39, National Computerization Agency40, City University of Hong Kong41, University of Idaho42, University of Zimbabwe43, University of Lisbon44, University of Central Lancashire45, Loyola Marymount University46, University of Natal47, University of Granada48, University of Botswana49, University of Jordan50, Babeș-Bolyai University51, University of Cyprus52, University of Belgrade53, KPMG54, University of Montpellier55, University of Zurich56, University of Alabama57, Baylor University58, Queen's University Belfast59, University of Ljubljana60, University of Haifa61, University of La Serena62, Florida Atlantic University63, University of California, Davis64, University of Dar es Salaam65, Ramapo College66, Cyprus College67, Middle East Technical University68, University of the South Pacific69, VU University Amsterdam70, State University of New York System71, University of the Aegean72, Vrije Universiteit Brussel73, University of Lethbridge74, University of Vienna75, University of Hong Kong76, Yuan Ze University77, Charles University in Prague78, Chonnam National University79
TL;DR: In the International Sexuality Description Project, a total of 17,804 participants from 62 cultural regions completed the RelationshipQuestionnaire (RQ), a self-report measure of adult romantic attachment as discussed by the authors.
Abstract: As part of the International Sexuality Description Project, a total of 17,804 participants from 62 cultural regions completedthe RelationshipQuestionnaire(RQ), a self-reportmeasure of adult romanticattachment. Correlational analyses within each culture suggested that the Model of Self and the Model of Other scales of the RQ were psychometrically valid within most cultures. Contrary to expectations, the Model of Self and Model of Other dimensions of the RQ did not underlie the four-category model of attachment in the same way across all cultures. Analyses of specific attachment styles revealed that secure romantic attachment was normative in 79% of cultures and that preoccupied romantic attachment was particularly prevalent in East Asian cultures. Finally, the romantic attachment profiles of individual nations were correlated with sociocultural indicators in ways that supported evolutionary theories of romantic attachment and basic human mating strategies.
314 citations
TL;DR: The recycling of catalyst particles after the quantitative reduction of 4-nitrophenol and the recovery of gold nanoparticles with unaffected particle morphology from the resin-bound gold nanoparticle entity have been reported.
Abstract: The immobilization of gold nanoparticles in anion exchange resin and their quantitative retrieval by means of a cationic surfactant, cetylpyridinium chloride, is studied. The resin-bound gold nanoparticles (R−Au) have been used successfully as a solid-phase catalyst for the reduction of 4-nitrophenol by sodium borohydride. At the end of the reaction, the solid matrix remains activated and separated from the product. The recycling of catalyst particles after the quantitative reduction of 4-nitrophenol and the recovery of gold nanoparticles with unaffected particle morphology from the resin-bound gold nanoparticle entity have been reported.
296 citations
TL;DR: In this paper, coal fly ash was used to synthesize X-type zeolite by alkali fusion followed by hydrothermal treatment and the maximum surface area of the product was found to be 383 m2/g with high purity.
Abstract: Coal fly ash was used to synthesize X-type zeolite by alkali fusion followed by hydrothermal treatment. The synthesized zeolite was characterized using various techniques such as X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, BET method for surface area measurement etc. The synthesis conditions were optimized to obtain highly crystalline zeolite with maximum BET surface area. The maximum surface area of the product was found to be 383 m2/g with high purity. The crystallinity of the prepared zeolite was found to change with fusion temperature and a maximum value was obtained at 823 K. The cost of synthesized zeolite was estimated to be almost one-fifth of that of commercial 13X zeolite available in the market.
14 Mar 2004
TL;DR: This paper compares two commonly used distance measures in vector models, namely, Euclidean distance (EUD) and cosine angle distance (CAD), for nearest neighbor (NN) queries in high dimensional data spaces and shows that CAD works no worse than EUD.
Abstract: Understanding the relationship among different distance measures is helpful in choosing a proper one for a particular application. In this paper, we compare two commonly used distance measures in vector models, namely, Euclidean distance (EUD) and cosine angle distance (CAD), for nearest neighbor (NN) queries in high dimensional data spaces. Using theoretical analysis and experimental results, we show that the retrieval results based on EUD are similar to those based on CAD when dimension is high. We have applied CAD for content based image retrieval (CBIR). Retrieval results show that CAD works no worse than EUD, which is a commonly used distance measure for CBIR, while providing other advantages, such as naturally normalized distance.
TL;DR: In this article, an optimum feed mix composition of 0.43-0.57 kg MD per kg of mango solids was obtained based on these properties of mango powder, and the optimum requirement for the TCP and GMS were found to be 0.015 kg perkg of mango solid.
TL;DR: In this article, a third order polynomial relationship was found to correlate the effective moisture diffusivity (D eff ) with moisture content, and the D eff increased for the same values of drying air temperatures and velocities as the applied microwave power.
TL;DR: In this article, the effects of surfactant-to-dye concentration ratio in the feed and the transmembrane pressure drop on permeate flux and observed retention of the dye have been studied as a function of the operating time.
TL;DR: Recurrent neural networks were used to train and forecast the monthly flows of a river in India, with a catchment area of 5189 km2 up to the gauging site, and performed better than the feed forward networks.
Abstract: Forecasting a hydrologic time series has been one of the most complicated tasks owing to the wide range of data, the uncertainties in the parameters influencing the time series and also due to the non availability of adequate data. Recently, Artificial Neural Networks (ANNs) have become quite popular in time series forecasting in various fields. This paper demonstrates the use of ANNs to forecast monthly river flows. Two different networks, namely the feed forward network and the recurrent neural network, have been chosen. The feed forward network is trained using the conventional back propagation algorithm with many improvements and the recurrent neural network is trained using the method of ordered partial derivatives. The selection of architecture and the training procedure for both the networks are presented. The selected ANN models were used to train and forecast the monthly flows of a river in India, with a catchment area of 5189 km2 up to the gauging site. The trained networks are used for both single step ahead and multiple step ahead forecasting. A comparative study of both networks indicates that the recurrent neural networks performed better than the feed forward networks. In addition, the size of the architecture and the training time required were less for the recurrent neural networks. The recurrent neural network gave better results for both single step ahead and multiple step ahead forecasting. Hence recurrent neural networks are recommended as a tool for river flow forecasting.
TL;DR: It is proved that max {d j +m j : v j ∈V}⩽ 2e n−1 +n−2 with equality if and only if G is an Sn graph (K1,n−1 ⊆Sn⊆Kn) or a complete graph of order n− 1 with one isolated vertex.
TL;DR: In this paper, the concept of group philicity (ωg) has been proposed to analyze intermolecular reactivity of some selected molecular systems and it can be found that DFT offers the possibility to calculate important functional group properties from the first principles in a non-empirical way.
TL;DR: In this article, the authors developed a full molecular model for AOT micelles in an apolar solvent, isooctane, and obtained nonspherical aggregates of elliptical shape with ratios between major axis, a, and minor axis, c, between 1.24 and 1.41.
Abstract: This paper reports results from four nanosecond constant pressure and temperature simulations of sodium di-2-ethylhexylsulfoccinate (AOT) and water reverse micelles (RMs) in an apolar solvent, isooctane. The concentration of our simulated micelles was chosen to fall in a range which in nature corresponds to the L2 phase of the ternary system. To our knowledge, this is the first study to develop a full molecular model for AOT micelles in an apolar solvent. We address here the problems of the shape of the RM and of its hydrophilic inner core. For the AOT−water system, we obtain nonspherical aggregates of elliptical shape with ratios between major axis, a, and minor axis, c, between 1.24 and 1.41. The hydrophilic inner core is also ellipsoidal with larger a/c ratios. Although experiments indicate that the L2 of the AOT−water−oil system is likely to be polydisperse, we can only simulate monodisperse RMs. Nonetheless, our simulations are capable of reproducing well the dimensions of the water pool and their de...
02 Mar 2004
TL;DR: In this article, the application of radial basis function (RBF) neural networks for fault classification and location in transmission lines is presented, where instantaneous current/voltage samples have been used as inputs to artificial neural networks (ANNs).
Abstract: The application of radial basis function (RBF) neural networks for fault classification and location in transmission lines is presented. Instantaneous current/voltage samples have been used as inputs to artificial neural networks (ANNs). Whereas, for fault classification, prefault and postfault samples of only the three-phase currents are sufficient, for fault location, postfault samples of both currents and voltages of the three phases are necessary. To validate the proposed approach simulation studies have been carried out on two simulated power-system models: one in which the transmission line is fed from one end and another, in which the transmission line is fed from both ends. The models are subjected to different types of faults at different operating conditions for variations in fault location, fault inception angle and fault point resistance. The results of the simulation studies which are presented confirm the feasibility of the proposed approach.
TL;DR: In this paper, the relation between density perturbations and brightness temperature fluctuations is investigated. But the relationship between the two sources of brightness temperature fluctuation is not discussed, except for fluctuations in the spin temperature and the H I optical depth.
Abstract: Loeb and Zaldarriaga have recently proposed that observations of the cosmic microwave background radiation (CMBR) brightness temperature fluctuations produced by H I inhomogeneities prior to reionization hold the promise of probing the primordial power spectrum to a hitherto unprecedented level of accuracy. This requires a precise quantification of the relation between density perturbations and brightness temperature fluctuations. Brightness temperature fluctuations arise from two sources: (1) fluctuations in the spin temperature, and (2) fluctuations in the H I optical depth, both of which are caused by density perturbations. For the spin temperature, we investigate in detail its evolution in the presence of H I fluctuations. For the optical depth, we find that it is affected by density perturbations both directly and through peculiar velocities which move the absorption features around in frequency. The latter effect, which has not been included in earlier studies, is similar to the redshift space distortion seen in galaxy surveys and this can cause changes of 50 per cent or more in the brightness temperature
TL;DR: In this paper, the electrical properties of polycrystalline samples of (Ba1−xSrx)(Zr0.05Ti0.95)O3 (x=0, 0.03,0.06 and 0.09) (BSZT) were prepared by a high-temperature solid-state reaction technique.
TL;DR: In this article, the gallery gap of Na-montmorillonite clay with stearyl amine was investigated using X-ray diffraction, Fourier transform infrared (FTIR) spectroscopy, and transmission electron microscopy (TEM).
Abstract: Nanocomposites were prepared with different grades of nitrile rubber with acrylonitrile contents of 19, 34, and 50%, with styrene–butadiene rubber (23% styrene content), and with polybutadiene rubber with Na-montmorillonite clay. The clay was modified with stearyl amine and was characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and transmission electron microscopy (TEM). The XRD studies showed an increase in the gallery gap upon the modification of the filler by stearyl amine. The intercalation of the amine chains into the clay gallery gap was confirmed by the presence of some extra peaks (2928, 2846, and 1553 cm−1) in the FTIR spectra. The clay–rubber nanocomposites were characterized by TEM and XRD. The mechanical properties were studied for all the compositions. An improvement in the mechanical properties with the degree of filler loading up to a certain level was observed. The changes in the mechanical properties, with changes in the nature and polarity of the rubbers, were explained with the help of XRD and TEM results. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 1573–1585, 2004
TL;DR: In this article, a predictive model of the combined effects of independent variables (pH, temperature, inoculum volume) for extracellular protease production from a newly isolated Pseudomonas sp.
TL;DR: In this paper, gold nanoparticles of variable sizes have been exploited to study their influence on the emission behavior of methylamino derivative of pyrene, and the mechanism of fluorescence quenching on the gold surfaces has been treated in the light of electron and energy-transfer processes.
TL;DR: In this paper, Mosambi juice was treated with pectinase enzyme at different durations (40−141 min), temperatures (32−49 °C), and at various concentration level of enzyme (0.0004−0.0014 w/v%).
TL;DR: In this article, three hundred forty middle-level managers from two private and two public sector manufacturing companies in India rated their superiors on 22 items of ethical leadership and found that the superiors self-rated themselves more favorably than their subordinates.
Abstract: Three hundred forty middle-level managers from two private and two public sector manufacturing companies in India rated their superiors on 22 items of ethical leadership. Factor analysis of the scores on such items yielded two dimensions of ethical leadership: (a) empowerment, and (b) motive and character. Items of the scale had high reliability, validity, and discriminative power. On two dimensions of ethical leadership, the superiors self-rated themselves more favorably than their subordinates rated them. This justified the proposal to consider the subordinates' ratings to their superiors in assessing ethical leadership. Subordinates perceived their superiors more ethical in private sector than in public sector. Subordinates' manipulative behavior, and cheating in performance and misuse of finance were less frequent in the presence of ethical superiors. Also, ethical superiors enhanced the job performance, job involvement and affective commitment of their subordinates but not their continuance commitment.
TL;DR: In this article, a discrete wavelet transform integrated with a fuzzy logic system is designed for fault classification of a transmission line possessing a series capacitor at the midpoint, which uses information obtained from the wavelet decomposition of current signals for faulty phase selection and section identification.
Abstract: Series capacitor protected by metal-oxide varistor and air-gap arrangement imposes problems to line protection and other online decisions. Discrete wavelet transform integrated with a fuzzy logic system is designed for fault classification of a transmission line possessing a series capacitor at the midpoint. The approach uses information obtained from the wavelet decomposition of current signals for faulty phase selection and section identification. Two different FLSs are designed for the two classification objectives in this paper.
TL;DR: The absorbed gamma dose rate levels of Chhatrapur beach area were similar to the monazite sand-bearing high background radiation areas of southern and southwestern coastal tracts of India and other similar areas of the world.
TL;DR: In this article, a 2.81×10−2 m o.d. stainless steel wetted-wall column at atmospheric pressure and constant feed gas ratio was used to investigate the selectivity of H2S from N2 streams containing H 2S and CO2 into aqueous solutions of 2-amino-2-methyl-1-propanol (AMP) as well as N-methyldiethanolamine (MDEA).