To improve the feasibility of developing melt blown nonwoven filtering material with given pore size specifications, the predictive power of a back‐propagation (BP) artificial neural network (ANN) that takes the processing parameters as its inputs for pore size and its distribution, characterized by the variation coefficient of pore size, was investigated. Twenty‐seven samples of melt blown nonwoven were produced and their images were collected using the scanning electron microscopy (SEM) method. The pore sizes were measured using digital image processing technology in which maximum entropy thresholding image segmentation based on a genetic algorithm was adopted. Seven BP ANN models were constructed by varying the number of neurons in the hidden layer. Metering pump frequency, mesh belt frequency, and the distance from die to collector (DCD) were chosen as the inputs of BP ANN. The results show that BP ANN can effectively reflect the nonlinear relationship between the processing parameters, and the pore size and its distribution. The mean absolute percentage errors (MAPE) between the predicted values and the measured values of the 7 models are all below 5％. Among these 7 models, the one that contains 7 neurons in its hidden layer has the minimum predictive error. The ANN model has stronger predictive power than the multiple linear regression model.

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The dyeing rate behavior (K/S‐t curve) of the intact jute fiber was investigated under the 2,5‐diaminotoluene (dAT)/2,4‐diaminophenoxy ethanol (dAPE) dyeing system with 75ml/L or 5ml/L of hydrogen peroxide(H₂O₂). Although the amount of dye uptake was dependent on the dye intermediate concentration, the fastest was the dyeing rate at pH7, followed in order by pH9 and pH5 at both H₂O₂ concentrations of bath solution. This order was the same order as the effect of pH on the rate of oxidative‐dye formation in the reaction solution containing the dissolved oxygen. However, the K/S‐t curve obtained by dyeing at pH9 in H₂O₂ solution of 5ml/L showed a sigmoid (S‐shaped) curve which is convex downward in the initial dyeing time. Furthermore, if the jute fibers pretreated with H₂O₂ were dyed under the same dyeing conditions, its amount of dye uptake was lower than that of the intact jute fiber. In particular, when dyed with the solution of pH9, and the lowest amount of dye uptake is obtained and its dyeing rate drew a downwardly convex curve. This result suggested that the oxidative decomposition reaction of jute fiber components, such as a pigment substance, might affect the oxidative dye concentration of the fiber surface which determines the dye uptake into internal fibers. When observing the time course of coloring phenomenon on the H₂O₂ treated jute fiber bundles in the oxidative dyeing bath with 75ml/L of H₂O₂, the coloring degree on the fiber surface was found to be thinner than that in the bulk solution. This observation indicates that the oxidative decomposition of some oxidation dyes generated in the solution/fiber interface occurs simultaneously at the fiber surface layer. Consequently, all of the oxidative dyeing behavior of the intact and the H₂O₂ treated jute fiber could explain satisfactorily by taking into account the decomposition reaction of one or both of the fiber component and the oxidation dye.

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In this study, transparent hybrid materials were prepared by combination of alumina fillers with different length, 15 nm (diameter) × 80 nm (length) and 4 nm (diameter) × 1400 nm (length), and acrylic surface modifiers having different numbers of acryl group. Alumina fillers used in this study could modify with acrylic surface modifier containing carboxyl groups by electrostatic interaction. The hybrid films obtained with organically modified alumina showed highly transmittance around 90％T, and TEM measurements clarified that alumina fillers dispersed homogeneously in hybrid film. As for hybrid films prepared short length alumina filler, the CTEs were decreased to around 10 ppm/K without reducing of their transparency. Furthermore, it was found that the usage of long length alumina filler allowed further reduction of CTE at lower alumina content, and improved mechanical properties and flexibility of resulting hybrid films on account of increasing of adhesion surface area between alumina and organic component.

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