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A new horizontal bubble train apparatus was developed to determine the different heterogenous gas-liquid interactions, particularly the uptake of gas-phase formaldehyde. The system operates with aqueous solutions and even concentrated sulfuric acid. Liquids are pumped through the apparatus' quartz tube at a controlled speed of 15-35 cm/s. From there, the liquid are examined for heterogenous gas-liquid interactions which involve the injection of a low-pressure gas flow and the subsequent sampling by a differentially pumped spectrometer. Results from the modeling indicate that pH and NaCl concentration play key roles in the uptake of formaldehyde.

A droplet train apparatus is used to measure the uptake of gas-phase ammonia by sulfuric acid surfaces. Uptake is measured as a function of temperature, gas-liquid interaction time, and acid concentration.

ABSTRACT [ABSTRACT FROM AUTHOR]

This study explored the attitudes of speech-language pathologists (S-LP) towards people who stutter (PWS). A 14-item semantic differential scale was utilized to assess the S-LPs' attitudes towards PWS and people who do not stutter (PWDS). In addition, the effect of familiarity and experiences with PWS was analyzed. The results showed that S-LPs have rather positive attitudes towards both PWS and PWDS. In addition, results of a multiple analysis of variance (MANOVA) showed that S-LPs perceived PWS more positively than PWDS on nine traits (sincereDSinsincere, likableDSnot likable, trustworthyDSnot trustworthy, physically normalDSphysically abnormal, reliableDS unreliable, good sense of humorDSpoor sense of humor, mentally stableDSmentally unstable, intelligentDSunintelligent, and employableDSunemployable). There appeared to be little effect for familiarity and experience with PWS on S-LPs' attitudes towards PWS. [ABSTRACT FROM AUTHOR]

We present a number of lower bounds for the h-vectors of k-Cohen-Macaulay (k-CM), broken circuit, and independence complexes. These lead to bounds on the coefficients of the characteristic and reliability polynomials of matroids. The main techniques are the use of series and parallel constructions on matroids and the short simplicial h-vector for pure complexes. [ABSTRACT FROM AUTHOR]

We have designed a 3He cryostat which can be inserted into a storage Dewar. This cryostat requires no external gas-handling system and has the advantages of extremely low (and recoverable) helium consumption, fast cooldown and warm-up times, excellent temperature range and stability, and low vibrational and electrical noise. The freedom from an external gas-handling system allows for portability and flexibility in its uses. Design and construction of the cryostat are presented, and operation and performance are discussed in some detail. To demonstrate performance of the cryostat, we present thermal boundary resistance measurements between 0.4 and 170 K for a solid–solid interface (Rh:Fe/sapphire). [ABSTRACT FROM AUTHOR]

We have designed [sup 4]He cryostats which can be inserted into storage Dewars. These cryostats have the advantages of extremely low (and recoverable) helium consumption, fast cool-down and warm-up times, excellent temperature range and stability, and they supply a low electrical noise and low vibration environment for electrical and thermal measurements. Design and construction details of one such cryostat are presented. We further present specific heat data on crystalline boron to demonstrate the performance of one of these cryostats in a particularly sensitive experiment. [ABSTRACT FROM AUTHOR]

We report measurements of the solid-solid thermal boundary resistance Rbd, spanning the temperature range from 1 to 300 K. Below 30 K, Rbd is found to be in agreement with the prediction of the acoustic mismatch model. The influence of diffuse scattering at the interface is found to have a very minor influence on Rbd. Above 30 K, Rbd decreases less rapidly with increasing temperature than predicted by the theory. Phonon scattering in thin (∼30 Å) disordered layers near the interface is shown to be a possible explanation. Implications for heat removal from integrated circuits are discussed. [ABSTRACT FROM AUTHOR]