Vapor Pressure

In this paper, FEA models are built for both flip chip BGA (FCBGA) and wire bond PBGA packages to predict the moisture distribution, followed by the calculation of vapor pressure distribution in the package using the micro-mechanics approach with consideration of the micro-void ...

Over440 yd,of radioactively contaminated soil containing toxic mercury was generated during a ComprehensiveEnvironmental Response, Compensation and Liability Act (CERCLA) removal action atBrookhaven,National Laboratory (BNL). The U.S. Department of Energy’s (DOE) Office of Scienceand,Technology Mixed Waste Focus Area (DOE MWFA) is sponsoring a comparison of severaltechnologies that may be used to treat these wastes and similar wastes at BNL and

This work provides thermodynamic data, in particular, liquid-state saturation vapor pressures of three common slightly water soluble secondary organic aerosol components, namely, malonic, succinic, and glutaric acids. A modified tandem differential mobility analyzer ...

There are little available toxicity data on the vast majority of chemicals in commerce. High-throughput screening (HTS) studies, such as being carried out by the U.S. Environmental Protection Agency (EPA) ToxCast program in partnership with the federal Tox21 research program, can generate biological data to inform models for predicting potential toxicity. However, physicochemical properties are also needed to model environmental fate and transport, as well as exposure potential. The purpose of the present study was to generate an open-source Quantitative Structure-Property Relationship (QSPR) workflow to predict a variety of physicochemical properties that would have cross-platform compatibility to integrate into existing cheminformatics workflows. In this effort, decades-old experimental property data sets available within EPA EPI SuiteTM were reanalyzed using modern cheminformatics workflows to build updated QSPR models capable of supplying computationally efficient, open, and tra...

One of the major issues in surface micromachining is process-induced failures of overhanged microstructures, after sacrificial removal. This failure process consists of temporary deformation due to capillary force and permanent stiction of the deformed microstructures to substrate due to the residue product. In order to alleviate this failure, some researchers have investigated the use of low surface-tension liquids, temporary support, sublimation of the final liquid or supercritical method. These conventional methods, however, are complicated liable to plasma damage during PR ashing, or require careful handling of the samples in rinse liquid. In this paper, we present a newly developed anhydrous HF gas-phase etching (GPE) technology for the removal of sacrificial TEOS (tetraethylorthosilicate) oxide. In order to minimize the capillary force of gas-liquid interface and residue product, methanol of low vapor pressure was employed as a catalyst instead of water vapor. The proposed process features simplicity, virtually no capillary forces and even compatibility with IC process as well. The effectiveness of HF GPE with methanol was verified by successfully fabricating the polysilicon cantilevers up to 1000 um in length with no stiction. The etch rate of HF GPE was 10-15 um/hr for the sacrificial TEOS oxide of 0.1-2 um channel height

The vapor-liquid equilibria of the pure components, 2,5-dimethyl furan (DMF), 1-butanol, 2-butanol, and 1-hexanol along with the binary mixtures (2,5-dimethyl furan + 1-butanol), (2,5-dimethyl furan + 2-butanol), and (2,5-dimethyl furan + 1-hexanol) were investigated experimentally by means of a static apparatus at temperatures between 313 and 393 K. The vapor pressures of the pure components were correlated with the Antoine equation. The experimental data of the mixtures were reduced by Barker method using a third-order Redlich-Kister equation. The calculated excess Gibbs functions, GE, exhibit positive deviations for all investigated temperatures and over the whole composition range. The NRTL and UNIQUAC models have also been used and good results were obtained in the prediction of the total pressure. Highlights Vapor pressures of 2,5-dimethyl furan + 1-butanol, + 2-butanol or +1-hexanol. The investigated temperatures are 313 K and 393 K. (2,5-dimethyl furan + 1-hexanol) system sh...

The surface energy balance of Lake Superior was measured using the eddy covariance method at a remote, offshore site at 0.5-h intervals from June 2008 through November 2010. Pronounced seasonal patterns in the surface energy balance were observed, with a five-month delay between maximum summer net radiation and maximum winter latent and sensible heat fluxes. Late season (winter) evaporation and sensible heat losses from the lake typically occurred in two- to three-day-long events, and were associated with significant release of stored heat from the lake. The majority of the evaporative heat loss (70–88%) and sensible heat loss (97–99%) occurred between October and March, with 464mm (2008–2009) and 645mm (2009–2010) of evaporative water loss occurring over the water year starting October 1. Evaporation was proportional to the horizontal wind speed, inversely proportional to the ambient vapor pressure, and was well described by the ratio of wind speed to vapor pressure. This ratio remained relatively constant between the two water years, so the differences in evaporative water loss between years were largely associated with differences in lake surface conditions (e.g. water temperature, ice cover, and ice duration). Since late-season water temperature decline is driven by evaporative and sensible heat loss, the potential for a negative feedback mechanism between evaporation and ice cover is discussed.

The term "ionic liquid" commonly refers to organic salts with relatively low melting points (below 100 °C) 1 which usually consist of an organic cation or anion and a counterion, in either organic or inorganic form. Ionic liquids have unique characteristics, including extremely low vapor pressure, excellent thermal stability, electrical conductivity, and high polarity. The miscibility of ionic liquids with

ABSTRACT Accurate isothermal vapor−liquid equilibrium data for the systems ethyl tert-butyl ether + ethanol at 24.8, 50, 65, and 90 °C and ethyl tert-butyl ether + water at 25.1 and 40 °C as well as pure component vapor pressures for ethyl tert-butyl ether were measured using a computer-operated static apparatus. Activity coefficients at infinite dilution and azeotropic compositions for the different temperatures were derived from the experimental P−x data. The data were simultaneously correlated together with published data with the help of either the UNIQUAC, NRTL, or Wilson model. However, the new data for the system ethyl tert-butyl ether + ethanol are in disagreement with some of the older data by Peng and Chao (Peng, C.-L.; Chao, K.-C. DIPPR Data Ser. 1994, 2, 23−27) and the pure component vapor pressure data for ethyl tert-butyl ether by Daubert (Daubert, T. E. AIChE Data Ser. 1991, 1, 80−88).

High-performance concrete (HPC) are subject to spalling under certain thermal and mechanical conditions. Spalling results mainly from two processes: a “thermo-mechanical” process in which the stress originates in the gradients of thermal deformation within the material, and a thermo-hydral process where spalling is due to the build-up of gas pressure fields in the porous network. This paper deals with the thermo-hydral process. An original device was designed in order to make simultaneous measurements of pressure and temperature at various positions in a concrete specimen (30×30×12 cm3) heated on one face up to 800°C. The specimen was also continuously weighed during the tests, thus, the mass loss, resulting mainly from water transport and loss, was recorded. This campaign was carried out on an ordinary concrete (OC) and a HPC (90 MPa). As expected, the pressure peaks were much higher than in HPC (40 bars) than in OC (20 bars). In HPC, these pressures exceeded the saturated vapor pressure. It is demonstrated that the thermal expansion of liquid water and the transport of water towards the inner part of the specimen play a significant role on the build-up of gas pressure. The experimental correlation between the pressure peaks and the plateau in the temperature curves confirmed the hypothesis that the drying front is preceded by a quasi-saturated layer that acts as a moisture clog.