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1

Design and Evaluation of the Thermal Properties of Di-, Tri- and Tetra-Azido-Esters

Kumar S., Kumar A., Yamajala K. D. B., Gaur P., Kumar D., Banerjee S.

Central European Journal of Energetic Materials

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2017

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Vol. 14, no. 4

844--860

EN

A group of polycyclic and aliphatic azido-esters (as energetic plasticizers) have been synthesized by simple synthetic routes and their molecular structures were confirmed by spectroscopic techniques. In addition, their thermal and rheological properties have been determined utilizing DSC, TGA, viscosity, and contact angle. Computational studies of these plasticizers have been performed by means of DFT (B3LYP/6-31G*) to estimate possible stable structures, energies, heat of formation, bond dissociation energies, IR and NMR spectra etc. Their compatibility with glycidyl azide polymer (GAP) binder was studied to explore their applicability in propellants. All of these molecules are novel and have been synthesized with the possibility of scale up.

2

Detection of hard exudates using mean shift and normalized cut method

Banerjee S., Kayal D.

Biocybernetics and Biomedical Engineering

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2016

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Vol. 36, no. 4

679--685

EN

As diabetic retinopathy (DR) is one of the main causes of loss of vision among diabetic patients, an early detection using automated detection techniques can prevent blindness among diabetic patients. Hard exudates constitute one of the early symptoms of DR and this paper describes a method for its detection using fundus images of retina, employing a combination of morphological operations, mean shift (MS), normalized cut (NC) and Canny's operation. This combined technique avoids over segmentation and at the same time reduces the time complexity while clearly delineating the exudates. Output of the proposed method is evaluated using public databases and produces sensitivity, specificity and accuracy as 98.80%, 98.25% and 98.65%, respectively. The ROC curve gives 0.984 as area under curve. The sensitivity, specificity, accuracy and area under curve of ROC indicate the effectiveness of the method.

3

Seismic and non-seismic soft-sediment deformation structures in the Proterozoic Bhander Limestone, central India

Sarkar S., Choudhuri A., Banerjee S., Van Loon A. J., Bose P. K.

Geologos

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2014

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Vol. 20, No. 2

89--103

EN

Numerous soft-sediment deformation structures occur within the Proterozoic Bhander Limestone of an intracratonic sag basin in a 750 m long section along the Thomas River, near Maihar, central India. Part of these deformation structures have most probably a non-seismic origin, but other structures are interpreted as resulting from earthquake-induced shocks. These seismic structures are concentrated in a 60 cm thick interval, which is interpreted as three stacked seismites. These three seismites are traceable over the entire length of the section. They divide the sedimentary succession in a lower part (including the seismites) deposited in a hypersaline lagoon, and an upper open-marine (shelf) part. Most of the soft-sediment deformations outside the seismite interval occur in a lagoonal intraclastic and muddy facies association. The SSDS within the seismite interval show a lateral continuity. They record simultaneous fluidisation and liquefaction. The bases of each of the three composing seismite bands are defined by small-scale shear folds, probably recording an earthquake and aftershocks. The presence of the three seismite bands at the boundary between the lagoonal and the overlying open-marine oolitic facies association suggests that the seismic event also triggered basin subsidence.

4

Study of hydrogen passivation in SiNx:H films sing Fourier transform infrared and photoluminescence spectroscopy

Chopra S., Gupta R. P., Joshi B. C., Eranna G., Banerjee S.

Materials Science Poland

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2009

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Vol. 27, No. 2

559--568

EN

Amorphous silicon nitride (a-SiNx:H) films were deposited at 300 °C by plasma-enhanced chemical vapour deposition. Silane/ammonia (SiH4/NH3) and silane/nitrogen (SiH4/N2) gas compositions were used at various flow rates to study the effect of hydrogen passivation of the films using the photoluminescence (PL) spectroscopy. Fourier transform infrared (FTIR) spectroscopy was employed to derive the relative changes in the total bonded hydrogen (TBH) concentration with increasing flow rates. The composition and the refractive indices of the as-deposited films were also extracted using the bond density calculations from FTIR spectra. The calculated refractive indices of the silicon nitride films were consistent with the ellipsometry measurements. The PL spectra were observed to be free from any interference effect and this was attributed to the nitrogen related defects in all the a-SiNx:H films. The films deposited using SiH4/NH3 showed a higher PL intensity than those deposited in a SiH4/N2 environment. A direct relation between the PL intensity and TBH content of the films was found.

5

Immunotherapy with interleukin-2: a study based on mathematical modeling

Banerjee S.

International Journal of Applied Mathematics and Computer Science

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2008

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Vol. 18, no 3

389-398

EN

The role of interleukin-2 (IL-2) in tumor dynamics is illustrated through mathematical modeling, using delay differential equations with a discrete time delay (a modified version of the Kirshner-Panetta model). Theoretical analysis gives an expression for the discrete time delay and the length of the time delay to preserve stability. Numerical analysis shows that interleukin-2 alone can cause the tumor cell population to regress.

6

Removal of Ni(II) from aqueous solutions using fly ash and montmorillonite

Banerjee S., Jayaram R.V.

Polish Journal of Chemical Technology

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2002

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Vol. 4, nr 4

6-10

EN

Adsorption of toxic metal ions like Ni(II) on heat treated montmorillonite, fly ash and impregnated fly ash was studied in terms of different parameters like initial metal ion concentrations, pH and temperature. Impregnated fly ash (IFAA1) showed much higher levels of adsorption capacity as compared to fly ash and heat-treated montmorillonite. The various rate parameters of the adsorption process have also been determined. Equilibrium adsorption model was arrived, based on Langmuir isotherm and the corresponding constants have been evaluated. Thermodynamic studies have also been carried out and values of standard free energy (AG°), enthalpy (AH°) and entropy (AS°) were calculated. The adsorption was found to be exothermic by these studies.

7

Shape analysis and volumetry using 3DVIEWNIX with applications to medical imaging

Banerjee S., Majumdar D.

Image Processing & Communications

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1999

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Vol. 5, no 2

3-10

EN

We present here linear, area and volume measures of substructures within structures, displayed as surface and volume rendered images, as well as individual two dimensional cross sections for purposes of quantitative assessment and show how these measures can provide biological markers for studying the extent of a disease, using an example from medical imaging.

8

A multimodal medical image processing system using a konowledge based approach

Banerjee S., Majumdar D.

Image Processing & Communications

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1998

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Vol. 4, no 1-2

47-80

EN

Shape analyses of anatomical structures / Regions of Interest (ROI) in medical images is important for the detailed study and objective assessment of the various properties of such structures. In addition, shape analyses of equivalent anatomical structures from different modalities provide complementary information about the ROI. In this paper we propose an image processing system that performs registration and shape alnalyses of segmented images of such structures obtained from the two modalities, x-ray Computed Tomography (CT) and Magnetic Resonance (MR) imaging using a knowledge based approach to identify these structures.