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Stresses in the individual wires of complex wire rope are determined for rope constructions having an internal-wire-rope (IWRC). The ropes may be pulled, twisted, and bent over a sheave or drum. The effects of friction are neglected. Specific results for a 6 × 25 filler-wire IWRC rope that is prevented from twisting indicate that the maximum stresses (exclusive of contact stresses) are typically 1.5 to 3 times as large as the nominal rope stress based on rope load and total metallic area.

Rates of cycling between glucose and glucose 6-phosphate and between glucose and pyruvate, and the effects of these cycles on glucose metabolism, were compared in hepatocytes isolated from fasted normal or streptozotocin-induced diabetic rats. In diabetic hepatocytes the rate of glucose phosphorylation was 30% lower than that in normal hepatocytes, and there was a doubling of the rate of glucose/glucose 6-phosphate cycling. In addition, the rate of glycolysis was 60% lower in diabetic hepatocytes. This inhibition of glycolysis and stimulation of glucose/glucose 6-phosphate cycling appeared to be a consequence of the elevated rates of endogenous fatty acid oxidation observed in diabetic hepatocytes. The proportion of glycolytically derived pyruvate that was recycled to glucose was more than doubled in hepatocytes from diabetic rats compared with normal animals. This increase also appeared to be linked to the high rates of endogenous fatty acid oxidation in diabetic cells. As a consequence of the increased rates of both these cycles, 85% of all glucose molecules taken up by diabetic hepatocytes were recycled to glucose, compared with only 50% in normal hepatocytes. Glucose cycling is therefore likely to make a substantial contribution to the hyperglycemia of diabetes.

Wittrick’s general one-dimensional equations governing the propagation of small elastic disturbances in a helical waveguide are solved by the method of characteristics, and numerical results for a particular interface problem are compared with strain gage records from an impacted experimental model. The agreement between theory and experiment is found to be excellent for the type of pulse considered, namely, an initially longitudinal compressive pulse approximately seventy rod-diameters in length.

The equations from Morley’s one-dimensional theory governing the motion of a curved beam subjected to an arbitrary pulse are solved numerically using the method of characteristics. Propagation of initially longitudinal pulses in beam assemblages with both straight and curved sections is investigated. Simulated isochromatic fringe patterns are constructed by a Calcomp plotter and are compared with actual photoelastic patterns. Remarkably good agreement is found between theory and experiment in all the cases investigated. It is concluded that Morley’s theory can be applied to pulse propagation problems of the type investigated.

The propagation of fluid transients through elbows is studied. A set of one-dimensional governing equations for the propagation of pressure pulses in an inviscid compressible fluid contained in a thin-walled naturally curved elastic tube is formulated and solved by two different techniques. For continuous waves, reflection and transmission coefficients for elbows are determined numerically by considering periodic waves in an assemblage of straight and curved tubes. For pulse propagation, the method of characteristics is employed to solve the assemblage problem. An experimental arrangement for pulse studies is described and experimental results are compared with numerical results from the method of characteristics.

The nonlinear, coupled equations of motion governing the axial and rotational displacements of a straight, single lay, twisted wire cable are presented. Linearization of the equations of motion allows a solution by Laplace transforms which is valid for arbitrary initial and boundary conditions. The longitudinal impact of a finite-length cable fixed at one end is considered in detail, and numerical results for this case are presented.

A new theory for the propagation of pressure pulses in an inviscid compressible fluid contained in a thin-walled elastic tube is presented. This theory represents an improvement over the classical waterhammer theory because the restriction that the speed of sound in the tube material must be much greater than that in the fluid has been removed and because the restriction that the pulse length must be much greater than the tube diameter has been somewhat relaxed. The new theory is applied to a water-filled copper tube with an axial impulsive force of very short duration applied either to a piston inserted in the anchored end of the tube or to a cap on the free end of the tube. Numerical solutions using the method of characteristics are presented, and comparison is made with the predictions of classical waterhammer theory. A check on the numerical solution is provided by the analytical solution for the capped tube and for the special case when the speeds of sound in the tube material and in the fluid are equal.

The dynamic, rigid, spherical indenter problem for the case of a thin viscoelastic plate is treated, and a numerical method is developed to handle the resulting equations of motion for a general linear viscoelastic material. Application to a constant tan δ model and comparison with experimental results indicate that the ball-bouncing technique can be extended to thin plate samples by the present theory if the loss tangent for the material is reasonably low.

Natural-graphite and finely ground artificial-graphite powders have been subjected to improved compacting ( “Shape”) techniques, developed by the National Coal Board, in an attempt to produce strong, dense materials suitable for use in atomic reactors. The densities of the natural-graphite and artificial-graphite compacts were 2.18 and 2.06 g/ml, respectively; the strengths were ∼2000 Ib/in2in each case. Whereas “Shape” techniques improved the compact quality of briquettable materials (e.g. artificial graphite ground to 12 μ dia.), non-briquettable materials (e.g. +350 B.S. mesh artificial graphite) could not be satisfactorily compacted by any means.Compact quality was very sensitive to particle size and size distribution in the sub-sieve range. On the whole, compact density decreased with decreasing particle size, whereas the strength increased. An empirical relationship S = KA 5/2,between the strength (S) and the specific surface area (A) of the powder, was obtained for electro-graphite powder compacted at 10 tons/in2Annealing these compacts at 800°C reduced their density by 1-2% but increased their strength by ∼30%.The compacts were extremely anisotropic and experiments which were aimed at reducing this anisotropy are described.