Jadavpur University

About: Jadavpur University is a education organization based out in Kolkata, India. It is known for research contribution in the topics: Population & Schiff base. The organization has 10856 authors who have published 27678 publications receiving 422069 citations. The organization is also known as: JU & Jadabpur University.

An intelligent traffic control system using RFID

Abstract: An architecture for creating intelligent systems for controlling road traffic is proposed. The system is based on a simple principle of RFID tracking of vehicles, can operate in real-time, improve traffic flow and safety, and fully automated, saving costly constant human involvement. The advantages ITCS can provide were demonstrated in detail which vouches for its effectiveness in traffic management systems. However, it is debatable whether monitoring every vehicle is morally acceptable and whether it is a violation of one of the basic civil rights-privacy.

Studies on a resistive gas sensor based on sol–gel grown nanocrystalline p-TiO2 thin film for fast hydrogen detection

Abstract: A thin layer (~1 μm) of sol–gel grown nanocrystalline p-type TiO 2 was deposited on a thermally oxidized p-Si (2–5 Ω cm resistivity and (1 0 0) orientation) substrate. The surface was characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM), which also confirmed the nanocrystallinity of the material. Optical absorption spectroscopy was carried out to calculate the band gap of the material. Two lateral Pd contacts were used as the catalytic metal electrodes on TiO 2 to fabricate the resistive gas sensor for hydrogen sensing. Detail gas response characteristics, selectivity and the stability of the sensor structure were studied. The sensors showed high response (~55%) to hydrogen with an appreciable short response time of 2 s at the optimized temperature, 175 °C and biasing voltage, 0.1 V in a steady dynamic atmosphere of 1% H 2 with N 2 as carrier gas. For practical applications, similar set of sensor experiments was also performed in air ambient. At 100 °C and 1.0 V bias the response magnitude was reduced to 49% but the response time came down to 1.3 s. The recovery time was lowest (~34 s) at 150 °C. The reduction in the recovery time in air is possibly due to quick removal of residual hydrogen from the surface of the sensor by interaction with oxygen present in air. The sensors showed selectivity to hydrogen and good stability. There was no degradation after working for 42 h in a discrete mode (6 h/day) in nitrogen and also in air. A possible gas sensing mechanism was suggested with a qualitative energy band diagram.

Production of poly-3-(hydroxybutyrate-co-hydroxyvalerate) by Haloferax mediterranei using rice-based ethanol stillage with simultaneous recovery and re-use of medium salts.

Abstract: Haloferax mediterranei holds promise for competitive industrial-scale production of polyhydroxyalkanoate (PHA) because cheap carbon sources can be used thus lowering production costs. Although high salt concentration in production medium permits a non-sterile, low-cost process, salt disposal after process completion is a problem as current environmental standards do not allow total dissolved solids (TDS) above 2000 mg/l in discharge water. As the first objective of this work, the waste product of rice-based ethanol industry, stillage, was used for the production of PHA by H. mediterranei in shake flasks. Utilization of raw stillage led to 71 ± 2 % (of dry cell weight) PHA accumulation and 16.42 ± 0.02 g/l PHA production. The product yield coefficient was 0.35 while 0.17 g/l h volumetric productivity was attained. Simultaneous reduction of BOD5 and COD values of stillage by 83 % was accomplished. The PHA was isolated by osmotic lysis of cells, purification by sodium dodecyl sulfate and organic solvents. The biopolymer was identified as poly-3-(hydroxybutyrate-co-15.4 mol%-hydroxyvalerate) (PHBV). This first report on utilization of rice-based ethanol stillage for PHBV production by H. mediterranei is currently the most cost effective. As the second objective, directional properties of decanoic acid together with temperature dependence of water solubility in decanoic acid were applied for two-stage desalination of the spent stillage medium. We report for the first time, recovery and re-use of 96 % of the medium salts for PHA production thus removing the major bottleneck in the potential application of H. mediterranei for industrial production of PHBV. Final discharge water had TDS content of 670 mg/l.

On further application of r m2 as a metric for validation of QSAR models

Abstract: Validation is a crucial aspect for quantitative structure–activity relationship (QSAR) model development. External validation is considered, in general, as the most conclusive proof of predictive capacity of a QSAR model. In the absence of truly external data set, external validation is usually performed on test set compounds, which are members of the original data set but not used in model development exercise. In the case of small data sets, QSAR researchers experience problem in model development due to the fact that the developed models may be less reliable on account of the small number of training set compounds and such models may also show poor external predictability because the models may not have captured all necessary features required for the particular structure–activity relationships. The present paper attempts to show that ‘true r(LOO)’ statistic calculated based on the model derived from the undivided data set with application of variable selection strategy at each cycle of leave-one-out (LOO) validation may reflect external validation characteristics of the developed model thus obviating the requirement of splitting of the data set into training and test sets. This approach may be helpful in the case of small data sets as it uses all available data for model development and validation thus making the resulting model more reliable. Copyright © 2009 John Wiley & Sons, Ltd.