Electrolytic board for the determination of lead, and some comments on the procedure for lead in low-grade tailings of the Southeast Missouri Lead District

Recent improvements in the practice of milling lead ores of the Southeast Missouri Lead Mining District has resulted in the production of low-grade mill tailings. The tenor of the lead in the tailings is often between 0.05 and 0.25 per cent. In view of the fact that large tonnages are handled daily and that further improvements are under way, it is imperative that the lead content of these tailings be accurately determined. For this purpose an electrolytic board, which speeds up the electrolytic determination of lead in low-grade mill tailings, has been devised at the Mississippi Valley Experiment Station of the United States Bureau of Mines, in cooperation with the Missouri School of Mines and Metallurgy, Rolla, Missouri. The electrolytic board is the result of several years work in cooperation with large lead mining companies. The method employed in the determination of small amounts of lead has been included as well as certain precautionary measures --Introduction, page 1

Synchronizer for random binary data

Simplified binary-data transition detector, for synchronization of relatively noise-free signals, can be used with radio or cable data-control links. It permits reception of binary data in absence of clock signal or self-clocking coder

Performance of Oil Pumping Rings: An Analytical and Experimental Study

A steady-state design computer program was developed to predict the performance of pumping rings as functions of geometry, applied loading, speed, ring modulus, and fluid viscosity. Additional analyses were developed to predict transient behavior of the ring and the effects of temperature rises occurring in the hydrodynamic film between the ring and shaft. The analysis was initially compared with previous experimental data and then used to design additional rings for further testing. Tests were performed with Rulon, carbon-graphite, and babbit rings. The design analysis was used to size all of the rings and to select the ranges of clearances, thickness, and loading. Although full quantitative agreement was lacking, relative agreement existed in that rings that were predicted to perform well theoretically, generally performed well experimentally. Some causes for discrepanices between theory and experiment are believed to be due to starvation, leakage past the secondary seal at high pressures, and uncertainties in the small clearances and local inlet temperatures to the pumping ring. A separate preliminary analysis was performed for a pumping Leningrader seal. This anlaysis can be used to predict the film thickness and flow rate thr ough the seal as a function of pressure, speed, loading, and geometry

The determination of friction-coefficients of water in small iron pipes

This thesis was undertaken to determine accurately the coefficients of friction of water, flowing at varying velocities in small iron pipes and elbows. It was the intention to obtain the condition of pipes and elbows similar to that met with in general practice --Introduction, page 1