In this paper, electrically conductive composites comprised of silicone rubber and titanium diboride (TiB₂) were synthesized by conventional mixing methods. Fine particles of TiB₂ (in micron size) and 10 parts per hundred parts of rubber (phr) proportion of carbon black (XC-72) were used to make the composites with HTV silicone rubber. The composites were cured at appropriate temperature and pressure and the effect on the electrical properties was studied. The resistance of the silicone rubber is ~ 10¹⁵Ω which decreases to 1–2 kΩ in case of composites with negligible effect of heat ageing. The hardness increases by ~ 35% simultaneous to the decrease of ~ 47% in the tensile strength. Morphological characterization indicates the homogeneous dispersion of the fillers in the composite.

This paper is concerned with the numerical solution of the mixed Volterra-Fredholm integral equations by using a version of the block by block method. This method efficient for linear and nonlinear equations and it avoids the need for spacial starting values. The convergence is proved and finally performance of the method is illustrated by means of some significative examples.

There are several methods in the literature to find the fuzzy optimal solution of fully fuzzy linear programming (FFLP) problems. However, in all these methods, it is assumed that the product of two trapezoidal (triangular) fuzzy numbers will also be a trapezoidal (triangular) fuzzy number. Fan et al. (“Generalized fuzzy linear programming for decision making under uncertainty: Feasibility of fuzzy solutions and solving approach”, Information Sciences, Vol. 241, pp. 12–27, 2013) proposed a method for finding the fuzzy optimal solution of FFLP problems without considering this assumption. In this paper, it is shown that the method proposed by Fan et al. (2013) suffer from errors and to overcome these errors, a new method (named as Mehar method) is proposed for solving FFLP problems by modifying the method proposed by Fan et al. (2013) . To illustrate the proposed method, some numerical problems are solved.

Major spices crops such as black pepper (Piper nigrum L.), cardamom (Elettaria cardamomum Maton.) and turmeric (Curcuma longa L.) production in India, is sustained losses due to several reasons. Among them, one of the major constraints are nematode infesting diseases, which causes significant yield losses and affecting their productivity. The major nematode pests infesting these crops include burrowing nematode Radopholus similis; root knot nematode, Meloidogyne incognita and M. javanica on black pepper. Whereas, lesion nematode, Pratylenchus sp., M. incognita and R. similis infesting cardamom and turmeric crops. Black pepper is susceptible to a number of diseases of which slow decline caused by R. similis and M. incognita or Phytophthora capsici either alone and in combination and root knot disease caused by Meloidogyne spp. are the major ones. Root knot disease caused by Meloidogyne spp. is major constraints in the successful cultivation and production in cardamom. Turmeric is susceptible to a number of diseases such as brown rot disease is caused by Fusarium sp. and lesion nematode, Pratylenchus sp. and root knot disease caused by M. incognita. Adoption of integrated pest management schedules is important in these crops since excessive use of pesticides could lead to pesticide residues in the produce affecting human health and also causing other ecological hazards.