Structure and properties of high-speed spun fibers of nylon 6 were studied in the range of take-up speeds from 5 to 12 kdmin. With increasing take-up speed, Young's modulus increased uniformly, while tenacity passed through a maximum at 8 km/min. WAXD data demonstrated the increase in the perfectness of the crystalline state with increasing take-up speed. First, the y-form crystal structure predominated up to 9 kdmin along with increase in its crystal size; second, in the range of 9 to 12 km/min, the a-form crystal structure appeared and developed as reflected by the increase in its crystal perfection. The structure-properties relationships are discussed, and it is indicated that the increasing tendency of Young's modulus over 9 kdmin can be attributed to the development of the a-form crystals.

Distribution behavior of minor elements has important implications for copper making processes. In this article, the experimental results of the distribution of silver, nickel, cobalt, lead, antimony and arsenic among the three melts of copper, white metal and silica-saturated iron silicate slag are described.varying from 0.7 to 20 kPa which are approximately proportional to the O2 pressures. The distribution ratios for an element X, defined as.can be arranged in the following orders:Thus, the impurity elements in this study can be grouped into three classes according to distribution tendencies:As and Sb are highly concentrated in the metal, Co is highly concentrated in the slag, and Ni and Pb are distributed among all three melts in rather similar concentrations. The distribution ratios of the present study generally agree with previous experimental data obtained for simplified two-melt systems. An oxidic dissolution of such forms as NiO, PbO and CoO in the slag is reasonably acceptable, while the possibility of metallic dissolution of Ag, As, Sb and Ni in the slag cannot be denied.

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Changes in the processes of drawing and/or annealing of polyethylene films were clearly shown by Cf values as described in the previous reports. However, it was also found some anomaly that the Cf does not depend on lamellar thickness (long period). These results were found in comparison of Cf values of solution grown crystals with those of melt grown crystals. In this report two series of the specimens having different lamellar thickness were prepared. The one was solution grown lamellae crystallized at different temperatures and the other those thicken by annealing at different temperatures. The theoretical relationship between Cf and long period was found in the former but not in the latter. Another anomaly was found in a melt-quenched specimen which has low degree of crystallinity. From these results, it was considered that the anomaly would be attributed to the difference between the fold conformation of the lamellae crystallized from solution and that from melt.