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Jute yarn reinforced polypropylene commingled composites were prepared by an environmentally benign technique called commingling method in which the matrix fibres and reinforcing fibres are intermingled together with good alignment. The dynamic mechanical properties or viscoelastic behaviour of these commingled composites were studied with reference to fibre content and various chemical treatments. The storage and loss modulus increased with fibre content where as tan δ decreased. KMnO4 and MAPP treated composites showed much higher storage and loss modulus values at all temperatures compared to untreated one. The glass transition temperature showed a marginal increasing tendency with fibre content and chemical treatments. The surface treatment mechanisms were supported by FT-IR spectra and the increase in interfacial adhesion after chemical treatments were supported by SEM images. Theoretical modelling was used to predict the values of storage modulus and tan δ and was found to be comparable with that of experimentally obtained results.

This paper mainly investigates the fabrication process of jute yarn reinforced, bidirectional thermoplastic commingled composites (both untreated and treated). Commingling method was used to prepare the composites wherein the Polypropylene yarn (PP yarn) and jute yarn were wound together onto a metal plate in a particular configuration and then compression moulded. The mechanical properties of the composites prepared from chemically treated jute yarn were found to increase substantially compared to those of untreated ones. The surface morphologies of the fracture surfaces of the composites were recorded using scanning electron microscope (SEM). The SEM micrographs reveal that interfacial bonding between the treated jute yarn and the matrix has improved significantly by chemical treatments. The various chemical treatment mechanisms have been supported by FT-IR spectra. Theoretical modelling was used to predict the tensile properties and was found to be in accordance with the experimental results.

The morphological, mechanical, and thermal stability of Nitrile rubber nanocomposites reinforced with fillers such as layered silicate (LS), calcium phosphate (CP) and titanium dioxide (TO) having different particle size and chemical nature were analyzed. The results revealed that the filler geometry played an important role on the mechanical and thermal stability of the composites. Calcium phosphate and titanium dioxide filled systems showed comparatively better mechanical and thermal stability compared to neat rubber. The activation energy needed for the thermal degradation was found to be higher for layered silicate filled system. DSC (Differential Scanning Calorimetry) analysis revealed a change in the Tg values as a result of the addition of fillers. This was more prominent with the case of layered silicate filler addition in comparison with calcium phosphate and titanium dioxide. The heat capacity values of the nanocomposites were carefully evaluated. The (∆Cp) with values obtained for different nanocomposites were correlated with the degree of reinforcement. It can be assumed that more polymer chains are attached on to the surface of the filler and there exists an immobilized layer around the filler surface and the layers do not take part in the relaxation process. The FTIR spectrum of the different samples highlighted the possible filler matrix interaction. The filler dispersion and aggregation in the polymer matrix were analyzed using X-ray diffraction studies (XRD), transmission electron microscopy (TEM), and atomic force microscopy (AFM).

In today's world, robots are used for almost all purposes. They find their application in defense, surveillance, transport and in many other places. Our project is based on building a robot having a capability to climb stairs carrying 10Kg of weight excluding its own weight. We will be loading fire extinguisher cylinders on the robot so that it can be used to douse fire. This robot will be able to go to places were human life can be at risk and can help in surveillance, as a camera will be placed at the front side of the robot which will send live video to the device linked with it. In this paper we present the structure, construction and application of a stair climbing robot.

GMSK is most notably used in the Global System for Mobile Communications (GSM). Performance of a cellular system is dependent on the efficiency of the modulation scheme in use.This paper evaluates the performance of GMSK for different channel conditions. The strong point of GMSK is its high spectral efficiency and power efficiency advantages which make it the preferred choice of modulation in fading mobile channels. Here, the GMSK system is implemented using SIMULINK and its performance under different channel models i.e. AWGN, Rayleigh and Rician fading channels has been evaluated using different analysis parameters such as BER (bit error rate), effect of change in BT, hard/soft decision decoding on system performance.