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DISCLAIMER This rc.port was prepared as an account of work sponsor_ by an agency of the Unite_l States Government. Neither the United States Government nor any agency ther_f, nor any of their employees, makes any warranty, express or implied, or assumes any |¢gal liability or responsibility for the accuracy, completeness, or usefulness of any inforrnati,on, apparatus, product, or process disclosed, or represents that its use would nio,tinfringe privately owned rights. Kefer-¢nc¢ herein to any specific commercial product, process, or servic_ by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its e,ndor_ment, re_om-m¢ndation, or favoring by the United States Government or any agency thereof. The views and opinions of authors express¢_!herein do no:t r_ev,¢ssarily_tate or rcfl,_t those of the United State, s Government or any agency rh, error',

The pressure drop across packed beds that are rotating differs in significant and unexpected ways, compared to the pressure drop behavior across conventional packed beds. For a wide range of operating conditions, (1) the pressure drop across an irrigated bed can be significantly lower than that across a dry bed and (2) for a fixed outer diameter, increasing the depth (i.e., more transfer units) of a rotating bed can result in a reduction in the pressure drop across the bed. Furthermore, the power required to spin the rotor diminishes as the vapor flow rate increases. Previously published correlations on the pressure drop across rotating beds do not explain or predict these phenomena. Here, a semiempirical sectional pressure drop model is presented, where all of these phenomena are related to the gas phase conserving its angular momentum as it flows from the shell through the rotating bed toward the centrally located exit.

p-type semiconducting diamond was grown by vapor deposition from a 0.83% diborane in methane gas mixture at 1050°C and 0.2 Torr on 0 to 1-μ nominal size natural type-I diamond powder. Total mass increases of about 9% were achieved which correspond to average linear growth rates of less than 10−3 μ/day. Evidence showing the growth was boron-doped diamond included chemical etching, x-ray and electron diffraction, density measurements, Seebeck and resistivity measurements, chemical analysis, optical measurements, induced electron emission spectroscopy, and scanning electron microscopy. The crystalline quality of the new diamond has not been established; it may be highly defective. A distinct change in color of the diamond seed crystals from an off-white or gray for virgin crystals to light blue after growth was observed. The results are further confirmation that diamond may be grown at low pressures where it is thermodynamically metastable with respect to graphite. It is also further evidence that boron is the element responsible for blue p-type diamonds.