The relation between apparent elongational viscosity obtained by using a spinline rheometer and a variety of flow contitions in its measurement is investigated for a dilute polymer solution. The numerical calculations are carried out for a FENE-P dumbbell model and the experiments are performed for a 100 ppm aqueous solution of polyacrylamide.
Elongational rates and elongational stresses are significantly changed along the spinline. The apparent elongational viscosity depends on the flow rate and the spinline length. It is found that this dependence of the spparet elongational viscosity is due to the effect of inertia. Finally, a comprarison is made between the apparent elongational viscosity and the steady elongational viscosity.

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It has been reported that low temperature plasma treatment offers a good shrink resistance property for wool fabrics. However it is not clear at present time how the changes in chemical structure on wool surface treated with the plasma affect the shrink resistance property.
In this study wool fabrics were treated with plasma and the surface of the fiber was analyzed by ESCA. It was found that the disulfide bonds involved in the fiber are severed in the process of plasma treatment and the residual disulfide bonds are related largely to the shrink resistance property. Also the contents of lipid were decreased by the treatment. The shrink resistance property was discussed in terms of the contents of disulfide bond and lipid contained in the surface of the plasma treated wool fibers.

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This paper describes flow characteristics in a weft-acceleration pipe of an air-jet loom, when a pressurized flow is given to a weft-guide pipe of the model-main nozzle. The central flow (flow in the wefl-guide pipe) includes not only flow naturally induced by pressurized annular flow, but also pressurized flow. Flow in the weftacceleration pipe was measured with a hot-wire anemometer when the flow-rate ratio, M, was changed stepwise. Where, M means the ratio of flow rate of the central flow to that of annular flow of the nozzle. Reynolds number in the acceleration pipc, Re, is constant (Re=1.7×10⁴).
The following results are obtained by this experiment :
(1) When the central flow is only naturally-induced flow, the mean-velocity-vector distribution toward downstream from the nozzle exit is biased slightly to the pipe wall. Velocity defect along an axis of the acceleration pipe increases remarkably owing to entrainment by annular flow. A point, which shows the minimum ratio ofU_c to U_m, moves toward upstream according to reduction of M, and the minimum value of U √U_m decreases, where U_c is mean velocity along the axis of the pipe and U_m is mean velocity through a section of the pipe. Especially, when only naturally-induced flow is considered, U_cian, has two extreme values at two points, x/D is 1 and 2, where x is an axial distance from the inlet of the acceleration pipe and D is diameter of the pipe. However, when x/D≥4, the values of U_c/U_m are nearly equal at any Ms and recovered slowly. And, when x/D≥6, no significant difference among velocity-vector distribution according to change of M can be found.
(2) Under any Ms, the wall pressure near the exit of the nozzle goes terribly upand down along the axis of the pipe. As a result, flow is separated from nozzle-side edge of the acceleation-pipewall. It is assumed that recirculation zone occurs along the pipe wall when M≤0.76. When M is smaller, recirculation zone becomes wider accordingly.
(3) With M being smaller, stronger turbulent flow occurs across each section of the pipe, and turbulence is dampened more slowly toward downstream.
As described above, when an appropriate nozzle-flow-rate ratio, the ratio of central-flow rate to annular-flow rate, is applied to flow of the weft-acceleration pipe, it can be found that flow, effective to acceleration of weft, is generated under the conditions such as reduced velocity defect along the axis of the pipe and dampened turbulent flow in the pipe.
The results obtained by this experiment prove indirectly that the main nozzles inserial structure, being employed recently, is useful for establishing steady-flying behaviour of weft.

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