The hydrogenation of carbon monoxide and carbon dioxide on various steel catalysts was studied in the temperature range of 800" to 1,300'F. and at pressures from 5 to 30 atm. The feed gases (3.75 to 20 SCFH) were passed over a catalyst bed of 1/8-h. steel balls supported in a brass-lined reactor 0.81 in. in d i m . The percentage of carbon oxides in the feed was 30% in the runs using a Hz-COZ f...

The measurement of large forces and the presence of errors due to dimensional coupling are significant challenges for multi-dimensional force sensors. To address these challenges, this paper proposes an over-constrained six-dimensional force sensor based on a parallel mechanism of steel ball structures as a measurement module. The steel ball structure can be subject to rolling friction instead ...

We investigate the distribution, mean value, variance and some limiting properties of an urn model of white and red balls under random multiple drawing (either with or without replacement) when the number of white and red balls added follows a schedule that depends on the number of white balls chosen in each drawing.

Suppose an urn contains M balls, of different types, which are removed from the urn in a uniform random manner. In the hypergeometric coupon collection problem, we are interested in the set of balls that have been removed at the moment when at least one ball of each type has been removed. In its dual, we are interested in the set of removed balls at the first moment that this set contains all o...

Using discrete element methods, geotechnical engineers can create “virtual laboratories” to simulate conventional laboratory tests. In this study, three-dimensional DEM simulations of direct shear tests are coupled with equivalent physical tests on steel balls. The macro-scale response of simulations is compared with the physical test results to validate the discrete element model and to gain i...

Methodological aspects of multivariate statistical models to describe and to assess data from computer-analyzed corneal topographers (CACT) are considered. The data generated by repeated curvature mappings of calibrated steel balls are discussed in detail with the objective of formulating the basic questions and suggesting directions to assess data from clinical applications of CACT. The interp...

A redetermination of the constant of gravitation has boon made using the torsion balance in vacuo. The large masses were steel cylinders weighing about 66 kg, and the small masses spheres of gold, platinum, and optical glass final result obtained is 6.670 X10" cm3 g" 1 sec." . While the results obtained appeared to differ slightly with small balls of gold, platinum, or glass, it was shown by a ...