In present study, optimization of four operating parameters of high energy planetary ball mill (i.e. milling time, milling speed, ball to material ratio and ball size) on dry grinding of jute fibre waste was performed. A three-level Box-Behnken design combining a response surface methodology was employed to study the response in terms of particle size and % sticking of material to mill. Analysis of variance of milling parameters showed coefficient of determination of 0.927 and 0.903 for particle size and material sticking respectively. The model equations were subsequently optimized using the canonical analysis with the help of SYSTAT software to minimize the particle size and material sticking. The optimum conditions were found 12mm for ball size, 47min for milling time, 9 for ball to material ratio and 870rpm for milling speed.

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In this study, polypyrrole (PPy) was coated by chemical oxidation through in-situ polymerization technique. Tetraethyl ammonium p-toluene sulfonate (TEAp-TS) was chosen as a doping agent along with FeCl₃ as oxidizing agent. Six different fabric samples were prepared by varying concentrations of monomer, doping agent and oxidizing agent in order to obtain samples with different electrical resistivity. Each sample was exposed to four different temperatures (80, 120, 160 and 200 °C) and electrical resistivity was recorded at different intervals in the range 0-600 seconds. In this way the influence of temperature on electrical resistivity of PPy coated cotton fabric samples was analyzed and found that resistivity decreases with the increase in temperature in two minutes significantly. FT-IR spectrum confirms that there is no change in PPy before and after heating of samples. SEM micrographs showed the deposition of PPy on cotton fibers surface.

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In preparation of microcapsules encapsulated herbal extract for clinical treatment, it is necessary to develop an appropriate method for maximizing the herb loading inside the microcapsules and increasing encapsulation efficiency. In order to design an appropriate method for microcapsules preparation, an orthogonal experimental design was used for determination of the optimum level of each variable in the process. In this study, there are four types of polymer used for developing microcapsules - chitosan (CMC), chitosan-sodium alginate (CSA), gelatin (GMC), and gelatin-arabic gum (GAG). Emulsion-chemical cross-linking method was used in preparing these four types of polymer microcapsules. An orthogonal array was employed to vary four independent variables including core-to-shell ratio (A), concentration of shell material in % (B), agitation speed in rpm (C) and cross-linking time in minutes (D) to optimize two dependent variables - particle size and yield of making such four types of polymer microcapsules. Based on the results, an optimum level of each variable and the order sequence of the importance of each variable in production of polymer microcapsules were determined. It is useful for practitioners in effectively preparation of encapsulated the herbal extract in microcapsules.

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Prediction equations of appearance of flared skirts are derived by the multiple regression of various drape coefficients with subjectively evaluated data which was obtained from observation of a walking model wearing each skirt. The subjective data was obtained for 9 evaluation terms of moving flared skirt by SD method evaluated by 23 university students aged from 19 to 22. It was found that “flowing”, “rhythmical”, “blowy”, “airy”, “flexible”, “graceful”, “lively”, “dynamic” and “beautiful” movement of flared skirts are evaluated objectively from a combination of various drape coefficients. These equations were inspected by the other 9 flared skirts and were proved to be reliable. Only 4 terms such as “rhythmical”, “airy”, “graceful” and “beautiful” are enough to evaluate the appearance. Almost all the evaluation terms were primarily dominated by conventional static drape coefficient (D_s) of fabrics.

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To encourage the conservation of resource and protection of the environment, recently, many countries are paying attention to the effective recycling of waste natural resources. In this study, the attention was focused on the waste vegetables. Vegetable sheets with different cutting size of vegetable and bamboo/vegetable composites with different bamboo content were developed by hot press molding. And tensile property tests were done. The vegetable sheet with different cutting sizes of vegetable showed different tensile properties. In addition, the bamboo pulp has good reinforcing property for vegetable composites, and the tensile strength and tensile modulus were improved remarkably compared with them of pure vegetable sheets.

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Fibrous materials are finding widespread applications in diversified areas, starting from clothing sector to medical fields, various structural and infrastructural applications of civil engineering, aerospace industries and even for energy generation and storage applications. In this paper, some of the most recent research studies on the application of fibrous materials in various advanced sectors have been reviewed and presented.

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