A rate equation should be obtained preparatory to designing a reactor. In light of the results of various published tests, the author assumed that the gaseous acetylation of dried rayon staple is governed primarily by the diffusion of acetic anhydride. Accordingly, experiments were made under various vapor tensions of acetic anhydride and the following rate equation was obtained: ∂M/∂θ=K_cc/Mⁿ Where M: Acetylated molal fraction. c: Concentration of acetic anhydride (kg/m³). θ: Time (min.) Values of coefficients are kc=0.00296 n=1.155 These values, however, are valid only in the following ranges: Concentration of acetic anhydride in vapor 0.7<c<1.5 (kg/m³) Temperature 120°C-145°C Concentration of acetic anhydride in vapor condensate emerging from reactor 760-780g/L (The remainder is acetic acid.)

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This article reports on a new type of spinning equipment which, using air flow, differs radically in the method of twisting from the ring spinning frame and which needs no ring, traveller or pot.
By this continuous spinning equipment, yarns, after spun with rovings can be wound directly into the cheese.
The equipment is capable of a spindle speed of more than 20, 000r.p.m. The yarn spun by this equipment-“.ir-spun yarn”, as we call it-has some defects, particularly in strength and elongation, when compared with ring-spun yarn.

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This article looks into problems which would accompany an attempt to increase the speed of looms equipped with a jacquard machine.
Each lingo vibrates violently with an increase in speed. The grade of its vibrations was judged by the distribution of points of the lingo's descents. As a way to judge that state, sparks were discharged from a lingo placed on special recording paper. A controlled plate for the harness was devised in order to narrow the range of distribution of points of the lingo's descent. A plate was also devised to control the vibrations of the harness. The defective parts resulting from a speed increase were improved, and the warp tension and the weight of the lingo were investigated. The results of these efforts suggest that the speed of a loom equipped with a jacquard machine, at present, 130rpm, can be increased to a maximum of 180rpm.

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