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Like other natural fibers jute, because of its hydrophilic nature, is incompatible with nonpolar plastics matrices. This has been the major handicap for preparing stable composites. In this paper we have used maleic anhydride grafted polypropylene, MAPP(G-3015) as the coupling agent for the surface modification of the fibers. Various parameters such as effect of fiber length, MAPP concentration, time period of MAPP treatment, percentage (wt./wt.) of fiber loading on mechanical properties such as tensile, flexural and impact strengths have been studied. It has been found that 30% fiber loading with 0.5% MAPP concentration in toluene and 5 min impregnation time with 6 mm average fiber lengths give the best results. Nearly 72.3% increase in flexural strength was observed in respect of treated composites. The fiber matrix interface was analyzed from the SEM micrographs. Water absorption of the composites has also been considerably reduced in the treated composites. Thermal behavior of the composites were also studied through DSC measurements. The MFI study also supports better fiber matrix adhesion.

This article concerns the effectiveness of MAPP as a coupling agent in sisal-polypropylene composites. The fiber loading, MAPP concentration, and fiber treatment time influenced the mechanical properties of the composites. It was observed that the composites prepared at 21 volume percent of fibers with 1% MAPP concentration exhibits optimum mechanical strength. SEM investigations confirmed that the increase in properties is caused by improved fiber-matrix adhesion. The viscoelastic properties of the treated and untreated composites were also studied. From the storage modulus versus temperature plots, an increase in the magnitude of the peaks was observed with the addition of MAPP and fiber reinforcement, thus showing an improvement in stiffness of the treated composites. The damping properties of the composites, however, decreased with the addition of the fibers and MAPP. The thermal properties of the composites were analyzed through DSC and TGA measurements.

Objective:To study the utility of Fournier's Gangrene Severity Index (FGSI) with mortality predictive value in our tertiary institutes in North India.Materials and Methods:A retrospective study of 95 cases of Fournier's Gangrene (FG), admitted from 2009 to 2011, was carried out. We analysed clinical and laboratory findings, various prognostic factors, surgical treatments and their outcomes in FG patients. FGSI was used as individual variable to estimate the severity of FG; the effects of these factors on mortality were also evaluated.Results:The overall mean age was 46.5 ± 15.6 (range 24-82) years. Anorectal and urological regions were the main sites of the infection. The most common site of infection origin was scrotum in 81.3% in group A and 41.2% in group B. One or more predisposing factors such as diabetes mellitus (DM; 55%) malignancies (4.6%), chronic renal failure (4.5%) and previous surgery (9.2%) were detected. We observed mortality in 26.5% cases (17/65). The FGSI calculated averaged 5.95 ± 365 in group A and 9.44 ± 2.56 in group B, at the time of admission (P > 0.05).Conclusion:In FG, an early diagnosis and early surgical debridement are essential. The FGSI seems to be an excellent tool for the outcome prediction.

Polypropylene/layered silicate nanocomposites were prepared from base polymer (10 MFI) and octadecylamine modified montmorillonite (1.30P nanomer), melt compounded with and without compatibilizer, i.e., maleic anhydride grafted polypropylene (Epolene-G3015). Physico-mechanical properties of the virgin PP and nanocomposites with different nanomer percentages and compatibilizer loadings were studied and compared. Thermal characteristics of nanocomposites were also compared with those of the virgin polymer. TEM analysis of the nanocomposites was carried out to study the dispersion of nanomer in the resulting hybrids. The nanocomposites showed improved mechanical properties over those of the virgin polymer with a marginal increase in specific gravity. Addition of compatibilizer further enhanced the mechanical properties of nanocomposites because of the compatibilization of the clay and host polymer interface. The uncompatibilized nanocomposites showed an increase in thermal stability and a higher melting point. However, the compatibilized nanocomposites showed delayed crystallization due to the presence of an oligomeric fraction of the added Epolene. Polym. Compos. 25:646-652, 2004.

Hybrid composites consisting of polypropylene (PP) and short sisal fibers were prepared by melt mixing followed by compression molding. Various types of chemical treatments such as alkali treatment, cyanoethylation, coupling agent treatment etc. were performed to improve the interfacial adhesion between the fibers and PP matrix. Variations in fiber loading, fiber length, coupling agent concentration and its treatment time period as a function of mechanical strength were studied. The morphology of the interface region was investigated through SEM analysis. Mechanical tests showed that the composites treated with MAPP of grade HC5 exhibited optimum strength. Nearly 50% increase in tensile, 30% in flexural and 58% increase in impact strengths were obtained in the case of composites treated with 1% MAPP concentration. Accelerated weathering and water absorption behavior of the MAPP-treated composites further confirmed an efficient fiber–matrix adhesion. Thermal measurements through DSC were also investigated to corroborate the findings of the mechanical data.

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Historically, manufacturing engineering education has focused on teaching mathematical models using simplifying assumptions that can mask the realities of complex manufacturing systems. Recent pedagogical approaches to manufacturing education have focused on developing a more holistic view of the manufacturing enterprise. In this paper, we describe the contents and development methodology of a Virtual Factory Teaching System (VFTS) whose aim is to provide a workspace that illustrates the concepts of factory management and design for complex manufacturing systems. The VFTS is unique in its integration of four domains: web-based simulations, engineering education, the Internet, and virtual factories. Evolutionary development of the VFTS is accomplished by separating the simulation model from the graphical interface and user interaction.