Analytical Study on Bill Discounting with Reference to Shār’Iah

With the growing economic industry, the importance of bill discounting is not obscured any more. It is undoubtedly one of the most important tools of trade financing. Now it has become very easy for importers and exporters to sale any product to a complete stranger anywhere in the world and get the bill against it discounted before its maturity date. That is why this tool is in the practice of all conventional banks. But regarding to shār’iah rulings its prevailed practice in conventional banks is not shār’iah compliance as this transaction consists of debt sale and interest. But due to it’s vitally need, Jurists of Islamic shār’iah have stepped forward with its different alternatives based on Můrabaha, Wākalāh, Můshāārkāh and Bāy’ Sālām in currency. In this article we have covered the causes behind the shār’iah rulings of prevailed bill discounting in conventional banks and addressed the Bāy’ Sālām as an alternative in currencies and its executive model in Islamic banks. Furthermore I have discussed the different opinions of modern scholars regarding these issues.

Synthesis and Characterization of New Polyamides, Poly Amide-Imide S, Polyimides and Polyurethanes Bearing Thiourea Moieties

This thesis primarily addresses the systematic modification of polyamides, poly(amide- imide)s, polyimides and polyurethanes to yield high performance poly(thiourea-amide)s, poly(thiourea-amide-imide)s, imide)s, poly(thiourea-ether-imide)s, poly(urethane-thiourea)s, poly(phenylthiourea-azomethine- poly(urethane-thiourea-imide)s and poly(urethane- azomethine-thiourea)s. The foremost goal of current research is the structural modification of polymers exploiting the synthetic chemistry to attain excellent solubility via slightly disrupting polymer chain regularity and packing. Various synthetic schemes were developed for the inclusion of thiourea moieties along with other desired linkages in these polymers. The designed monomers (dinitro, diamines, dicarboxylic acids, diacid chlorides, diols and diisocyanates) bearing pre-formed linkages were then synthesized and employed for the preparation of novel thiourea-based polymeric materials. The incorporation of different functional groups provides an opportunity to control certain physical properties such as solvent miscibility, η inh , crystallinity, molecular weight, thermal stability and flame retardancy of the resulting polymers. The effect of thiourea and other functional groups on the properties of newly synthesized polymers were scrutinized together with their structure-property relationship. Major tools utilized for the examination of polymer properties are FTIR, 1 H NMR, solubility, viscometry, GPC, TGA, DSC and XRD. Novel thiourea-based polymers demonstrated outstanding thermal stability without deteriorating their organosolubility or processability. Another objective of the work was to evaluate the expedient applications and potential relevance of these valuable high-performance materials for advanced technologies. The processable poly(thiourea-amide)s, poly(thiourea- amide-imide)s, poly(thiourea-ether-imide)s and poly(urethane-azomethine-thiourea)s were found to have superior thermal stability as well as non-flammability. Poly(phenylthiourea-azomethine- imide)s having C=S and –C=N– moieties can act as imminent contenders to fabricate certain electrically conducting materials. Poly(thiourea-amide)s, in addition to the excellent solubility and thermal resistance, can be employed as solid extracting phases for the elimination of environmentally toxic metal ions from aqueous media. Prior to this effort, reported in peer- reviewed journals, synthesis of high temperature polymers bearing C=S entity was an unexplored area. Easy processability, high molar mass, heat and flame stability, electrical conductivity, etc, depict their high adaptability in future, rendering them backbone materials in polymer science.