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The Peng-Robinson equation gives poor results when used to calculate liquid phase densities. In order to improve the calculated liquid phase densities, the b constant in the Peng-Robinson equation has been expressed as a linear function of temperatrue. Preliminary evaluation indicates that this modification significantly improves predicted liquid densities for pure components.

Impurity doped silicon detector arrays sensitive to long ir wavelengths, based on monolithic processing, were designed and developed. These arrays provide optimized performance utilizing ir transparent detector contacts and reflecting counterelectrodes while minimizing electrical and optical cross talk and providing precise optical definition for the detectors. The microelectronic batch processing procedures are discussed, and the array performance obtained using these procedures is presented. This includes spectral response, the dependence of detectivity on temperature and frequency, the electrical and optical cross talk, and the optical definition obtained. The development is expected to serve as a processing guide for future arrays which will include on-chip signal processing.

Meteorological conditions associated with more than 150 intense convective precipitation events have been examined. These heavy rainfalls caused flash floods and affected most geographic regions of the conterminous United States. Heavy rains associated with weather systems of tropical origin were not considered. Analyses of surface and standard level upper-air data were undertaken to identify and define important synoptic and mesoscale mechanisms that act to intensify and focus precipitation events over specific regions. These analyses indicated that three basic meteorological patterns were associated with flash flooding in the central and eastern United States. Heavy convective precipitation episodes that occurred in the West were considered as a separate category event. Climatological characteristics, composite analyses, and upper-air data are presented for these four classifications of events.The large variability of associated meteorological patterns and parameters (especially winds aloft) makes identification of necessary conditions for flash flood-producing rainfall quite difficult; however, a number of features were common to many of the events. An advancing middle-level, short-wave trough often helped to trigger and focus thunderstorm activity. The storm areas were often located very near the mid-tropospheric, large-scale ridge position and occurred within normally benign surface pressure patterns. Many of the intense rainfalls occurred during nighttime hours. These elusive characteristics further complicate a difficult forecast problem.

We demonstrate the thermal oxidation of the Si side of the interface in epitaxial Si films grown on yttria-stabilized cubic zirconia, 〈Si〉/〈YSZ〉, to form a dual-layer structure of 〈Si〉 /amorphous SiO2/〈YSZ〉. The SiO2films are formed in either dry oxygen (at 1100‡C) or in pyrogenic steam (at 925‡C) by the rapid diffusion of oxidizing species through the 425 Μm thick cubic zirconia substrate. For instance, a 0.17 Μm thick SiO2layer is obtained after 100 min in pyrogenic steam at 925‡C. This relatively easy transport of oxidants is unique to YSZ and other insulators which are also superionic oxygen conductors, and cannot be achieved in other existing Si/insulator systems, such as Si-on-sapphire. The present process eliminates the most

A group contribution method for predicting the viscosity of binary and ternary liquid mixtures is proposed. Tests of the method against existing literature data show excellent agreement. Parameters for eight groups are presented.

The latent heat of vaporization of a pure substance is often required in many engineering design/process calculations. Knowledge of the latent heat of vaporization can be of particular value when dealing with a material for which complete enthalpy data are not available. A method has been developed for making accurate reliable estimates of the latent heat of vaporization when only the vapor pressure and the critical constants of the material are known.

Heat transfer coefficients calculated from accepted correlations, but using physical properties derived from different sources, are compared with experimentally determined local heat transfer coefficients. In all cases, consistent, accurate property data yield more accurate estimates of the heat transfer coefficients.

The validity of several frequently employed satisfaction scales was tested using data from a study of satisfaction with tourism in Nova Scotia. Although all measures performed well, one, the delighted-terrible (DT) scale, appears to be superior. Satisfaction with tourism is shown to be an independent measurable construct.

We report the effect of steam oxidation at 875° C on the electrical resistivity, crystalline quality (measured by ion channeling), and Al concentration (measured by secondary ion mass spectrometry) in 0.25 μm thick, Si-implanted and recrystallized, Si-on-sapphire films. After a deep Si implantation (180 keV, 1.4×l015Si/cm2) at room temperature, and solid-phase epitaxial regrowth from the non-amorphized, 0.03 μm thick surface region, the initially undoped SOS films become doped p-type, and their resistivity decreases from (1−5)xl014ficm to 0.5 Ωcm. The doping is due to electrically active Al, released from the A12O3by the Si implantation, and present in the recrystallized films at a concentration of ≃2×l016Al/cm3. After a 75 min steam oxidation at 875 °C, which consumes 0.06 Μm of Si, the resistivity of the recrystallized films increases to over 40 Ωcm, but the Al concentration is unchanged. The oxidation also uncovers higher quality material below the non-recrystallized surface layer. A semi-quantitative model is proposed to explain the electrical data, based on the diffusion of oxygen from the Si/SiO2interface into the SOS film during oxidation, and the formation of Al-O-Si neutral complexes. Data on the stability of the high-resistivity films against high-temperature annealing or re-amorphization and annealing is given.

Highlights from the article: When I was asked to fit new skirtboards to an existing staircase, I decided to take my experience templating countertops and apply it to the stairs. I was looking at different drill/impact-driver storage methods bandied around on Instagram and Pinterest. The simplest method I have come up with is to use a quick-adjusting clamp or two on the top jamb extension with the bar pointing up toward the ceiling.

The occurrence of Creutzfeldt–Jakob disease (CJD) among American Indians and Alaska Natives in the United States was evaluated using national multiple cause-of-death data and medical information obtained from state health departments. Twelve CJD deaths were identified for 1981 through 2002, and the average annual age-adjusted death rate was 0.47 per million population. This rate was significantly lower than that for whites and similar to the rate for African Americans.

The article focuses on formation of shims with the use of waste scraps from tablesaw rips and paper.

The article discusses the importance of thermodynamic properties for predicting pipeline operations accurately. It proposes an algorithm to estimate pressure drops and flow conditions along single-phase gas and low-liquid content, two-phase-flow natural gas pipelines. Gas analysis and calculation show the impact of different design variables on liquid formation in the line and online pressure drop as demonstrated by the Masjed-I-Soleiman (MIS) to Mahshahr gas pipeline in southwest Iran.