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The impact of model microphysics on the relationships among hydrometeor profiles, latent heating, and derived satellite microwave brightness temperatures [T.sub.B] have been examined using a nonhydrostatic, adaptive-grid cloud model to simulate a mesoscale convective system over water. Two microphysical schemes (each employing three-ice bulk parameterizations) were tested for two different assumptions in the number of ice crystals assumed to be activated at 0[degrees]C to produce simulations with differing amounts of supercooled cloud water. The model output was examined using empirical orthogonal function (EOF) analysis, which provided a quantitative framework in which to compare the simulations. Differences in the structure of the vertical anomaly patterns were related to physical processes and attributed to different approaches in cloud microphysical parameterizations in the two schemes. Correlations between the first EOF coefficients of cloud properties and [T.sub.B] at frequencies associated with the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) showed additional differences between the two parameterization schemes that affected the relationship between hydrometeors and [T.sub.B]. Classified in terms of [T.sub.B], the microphysical schemes produced significantly different mean vertical profiles of cloud water, cloud ice, snow, vertical velocity, and latent heating. The impact of supercooled cloud water on the 85-GHz [T.sub.B] led to a 15% variation in mean convective rain mass at the surface. The variability in mean profiles produced by the four simulations indicates that the retrievals of cloud properties, especially latent heating, based on TMI frequencies are dependent on the particular microphysical parameterizations used to construct the retrieval database.

The impact of model microphysics on the retrieval of cloud properties based on passive microwave observations was examined using a three-dimensional, nonhydrostatic, adaptive-grid cloud model to simulate a mesoscale convective system over ocean. Two microphysical schemes, based on similar bulk two-class liquid and three-class ice parameterizations, were used to simulate storms with differing amounts of supercooled cloud water typical of both the tropical oceanic environment, in which there is little supercooled cloud water, and midlatitude continental environments in which supercooled cloud water is more plentiful. For convective surface-level rain rates, the uncertainty varied between 20% and 60% depending on which combination of passive and active microwave observations was used in the retrieval. The uncertainty in surface rain rate did not depend on the microphysical scheme or the parameter settings except for retrievals over stratiform regions based on 85-GHz brightness temperatures [T.sub.B] alone or 85-GHz [T.sub.B] and radar reflectivity combined. In contrast, systematic differences in the treatment of the production of cloud water, cloud ice, and snow between the parameterization schemes coupled with the low correlation between those properties and the passive microwave [T.sub.B] examined here led to significant differences in the uncertainty in retrievals of those cloud properties and latent heating. The variability in uncertainty of hydrometeor structure and latent heating associated with the different microphysical parameterizations exceeded the inherent variability in [T.sub.B]--cloud property relations. This was true at the finescales of the cloud model as well as at scales consistent with satellite footprints in which the inherent variability in [T.sub.B]--cloud property relations are reduced by area averaging.

We have investigated by numerical simulation the hypersonic and high-enthalpy flows around a reentry body, which Sasoh et al. examined experimentally in an expansion tube facility (Sasoh, A., Ohnishi, Y., Ramjaun, D., Takayama, K., Otsu, H., and Abe, T., 'Effective Test Time Evaluation in High-Enthalpy Expansion Tube' AIAA Journal, Vol. 39, No. 11, 2001, pp. 2141-2147). For the experiment, the evaluation of the timing at which the test flow is attained and the free. stream condition of the test flow are the most crucial issues. Therefore, it was necessary to validate these issues in another way, rather than the simple estimation by Sasoh et al. based on the pressure and spectral emission measurements. Thus, the experimental result was intensively investigated compared to the numerical result based on the experimentally determined freestream condition. In the context of the thickness of the radiating shock layer for which the experimental result was obtained, the results show a good agreement, and we can conclude that the test time and the freestream condition in the experiment are reasonably estimated.

Condensed materials vaporization when in contact with high-current discharge plasmas is considered.

Additional information is presented concerning the ablation of animal cartilage by a XeCl laser beam.

Research was conducted to address questions on the heat of vaporization of silicon through a benchmark calculation of the total atomization energy of SiF4 molecule. Results supported the suggestion of Grev and Schaefer that the uncertain JANAF/CODATA value of 106.5+1-1.9 kcal/mol must be revised to a lower value. Future studies on heats produced by silicon compound formation could take advantage of the revision.

Analysis of gallium sesquiselenide, Ga2Se3, using simultaneous Knudsen effusion and torsion effusion showed that anomalous results were caused by condensed phase transition at 1225plus/minus 10 K, a range at which both condensed phases reach equilibrium with the vapor. Ga2Se(g) and Se2(g) were the principal products of congruent effusion below the given temperature range, while same species results were obtained above the given range.

Comparisons of the differences in heats of vaporization of alcohols (ROH) and their analogous hydrocarbons (RCH3) led to the conclusion that this difference represents the contribution of the hydrogen bond to the value of the change in the heat of vaporization. Also, alcohols are self associated in pure liquids in cyclic clusters each of four alcohols. These conclusions are the result of extensive, previous studies of PVT relations in vapors, heat capacities and IR spectra in solutions.

The HART facility is a flexible multi-bank system for testing independently augmented railgun concepts. The HART I launcher has a 1.27-cm square bore with GlidCop rails and Al2O3 insulators. The bore components and augmentation turns are supported by G-10. Features which make HART I well suited for pursuing research on the approach of independent augmentation are its bore design, which can accommodate a variety of insulator types in tile or strip form, and the densely placed B-dot instrumentation. Ex-bore velocity tracking is provided by light gates, cw x-rays, and breakwires. The modular power facility provides a high degree of flexibility in waveforms and timing. The use of parallel coaxial cables in the pulse-power circuits simplifies the configuration of the capacitor banks into individual or parallel arrangements, with inductors chosen to provide desired pulse shapes. Tests are planned by using simulations to choose the primary and augmenting currents and their independent timing. Independent augmentation allows hypervelocity projectile tests to be fired at low plasma armature currents. With low-ablation insulators, this reduces wear on the bore and allows many tests to be conducted before retiling. Both projectile and free-running arc tests were conducted on the gun with the objective of verifying augmented operation. Free-running arc tests are initiated with an in-bore spark gap. Using a helium preinjector and wire fuses, projectiles have been launched with the absence of secondary arcs.

Optical transmission analysis was used to investigate explosive vaporization of a transparent liquid film on an opaque solid surface induced by excimer-laser-pulsed irraiation. The results showed that upon absorption of the laser pulse, a strongly superheated thin liquid layer was formed at the interface. When the liquid-film thickness was not significant to the film explosion arrangements, the surface tension was observed to be crucial to the process.

A simple atom and group-equivalent methods is presented that will convert quantum mechanical energies of molecules to gas phase heats of formation of CHNO systems. Heats of sublimation and vaporization derived from information obtained from the quantum-mechanically calculated electrostatic potential of each isolated molecule.

The threshold fluences at which vaporization is initiated at the tip of a multimode fiber that is submerged in water were investigated when free-running and Q-switched thulium laser pulses ([Lambda] = 2.01 [micro]m) were applied with different pulse energies. We focused on the quantification of temporal and spatial fluence modulations of the beam profile at the tip of a 400-[micro]m fiber. The spatial and the temporal fluence peaks over the average fluence were measured to as high as 1.5 and 4 in the Q-switched mode, respectively, and 2.5 and 40 in the free-running mode, respectively. The fluence peaks significantly influence the vaporization process. An increase in the threshold fluence with increasing pulse energy was found for the Q-switched mode, but there was a decrease for the free-running mode. Pressure transients of the order of 1 kbar and temperatures higher than 200 [degrees] C were calculated for a 30-mJ Q-switched laser pulse at the onset of vaporization. Collecting all the data allowed us to trace the thermodynamic path of rapid heating and vaporization in a phase diagram of water. OCIS codes: 140.3070, 140.6810, 170.1020, 030.6140, 030.1670.

J.R. Thome developed a consecutive-photo method which he claimed was a new technique. However, investigations show that the method has already been used by C.N. Ammerman and S.M. You in the past using a relatively low-speed digital camera in place of a true high-speed digital camera and other researchers using high-speed cine cameras. Despite the renewed interest shown by Thome in the fundamentals of nucleate pool boiling, it would be wise to consider other researchers' contributions.

Richard Edward Honig did pioneering work on the vaporization of solids and mass spectrometry techniques for characterizing solid surfaces. He later headed up the RCA Laboratory and got involved in laser desorption mass spectrometry and material science research.