Including Dispersion in an Equation of State Compositional Simulator

One of the state-of-the-art, equation of state, compositional simulators, the Young and Stephenson formulation, was improved to model physical dispersion as the first step of a series of modifications. The physical dispersion term was implemented as generally as possible since it was treated explicitly. Numerical dispersion ts usually at least an order of magn1tude larger than physical dispersion and masks its real effect on an EOR process. Hence, to reduce numerical dispersion, two versions of two-point upstream weighting and Chaudhart's technique were tested and compared. Through several test cases, Chaudhart's technique was discarded due to its inabt1ity to model small physical dispersion. Using two-point upstream weighting, various application runs, including 1-D, 2-D areal, and 2-D cross-sectional geometries, were made to investigate the effect of longitudinal and transverse dispersion on a miscible displacement process.Petroleum and Geosystems Engineerin

Factors Affecting Retweetability: An Event-Centric Analysis on Twitter

In Twitter information primarily propagates through retweet mechanism. While a massive amount of tweets gets generated everyday, only a handful of them get retweeted widely. In this study, we have investigated the impact of user-roles in retweet phenomena. We have introduced the concept of “Information Diffusion Impact” (IDI) and identified three important user roles, namely “information starter”, “amplifier”, and “transmitter”. Retweetability has been modeled using IDI impact for different user roles along with the content features like presence of hashtag, URL etc. Further, the effect of a major event on the factors affecting retweetability has been investigated. Our findings demonstrate that retweetability is significantly affected by amplifiers and information-starters and these effects change substantially due to event. We have also reexamined our model in another dataset of the Boston marathon bomb blast, 2013 and the outcome of this analysis is in good agreement with our findings from Japan earthquake dataset

Capillary-assembled microchip as an on-line deproteinization device for capillary electrophoresis

A capillary-assembled microchip (CAs-CHIP), prepared by simply embedding square capillaries in a lattice polydimethylsiloxane (PDMS) channel plate with the same channel dimensions as the outer dimensions of the square capillaries, has been used as a diffusion-based pretreatment attachment in capillary electrophoresis (CE). Because the CAs-CHIPs employ square-section channels, diffusion-based separation of small molecules from sample solutions containing proteins is possible by using the multilayer flow formed in the square section channel. When a solution containing high-molecular-weight and low-molecular-weight species makes contact with a buffer solution, the low-molecular-weight species, which have larger diffusion coefficients than the high-molecular-weight species, can be collected in a buffer-solution phase. The collected solution containing the low-molecular-weight species is introduced into the separation capillary to be analyzed by CE. This type of system can be used for CE analysis in which pretreatment is required to remove proteins. In this work a fluorescently labeled protein and rhodamine-based molecules were chosen as model species and a feasibility study was performed. [Image: see text