Accurate modeling of the storage or sequestration of CO2 injected into subsurface formations requires an accurate fluid model. This can be achieved using compositional reservoir simulations. However, sophisticated equations of state (EOS) approaches used in current compositional simulators are computationally expensive. It is advantageous and possible to use a simple, but accurate fluid model f...

Crater rays are formed during a cratering event as target material is ballistically ejected to distances of many crater radii forming narrow, generally high albedo, approximately linear features extending outward from the crater. The nature of crater rays was examined for the lunar crater Copernicus using new information on, the composition of surface material (from near-IR reflectance measurem...

Global public opinion has emerged as an important factor affecting international relations. But have U.S. public diplomacy efforts during the post-9/11 period successfully improved foreign publics’ images of the U.S. and its foreign policy? We examine this question by estimating the effects of U.S. high-level visits to foreign countries on public opinion in those countries. Our compositional da...

Compositional data on a range of sulphide and sulphosalt minerals from the hydrothermal vein deposit of Herja in the Baia Mare metallogenic area are presented. The presence of zinkenite, chalcostibite, diaphorite, fülöppite, boulangerite, bournonite, electrum and manganite are confirmed in the Herja ores for the first time. In addition, compositions close to veenite, twinnite and heteromorphite...

This paper reviews the use of electron probe microanalysis, scanning electron microscopy and analytical electron microscopy in the measurement of compositional data obtained from diffusion couples. Methods to obtain x—ray spatial resolution as low as mm with the AEM are described. In addition, techniques for improving the detection and for increasing the accuracy of compositional analyses are s...

The precipitation of asphaltenes in two Mexican crude oils was measured using a combination of high-pressure isothermal expansion and atmospheric titration with nalkanes. Experiments were carried out from the liveand tank-oil type of samples of the same crude oils. For the oils investigated, compositional data, precipitation phase diagrams, and bubble point pressures are reported. A theoretical...

For the application of many statistical methods it is necessary to establish the measure of di erence to be used This measure has to be de ned in accordance with the nature of the data In this study we propose a measure of di erence when the data set is compositional We analyze its properties and we present examples to illustrate its performance INTRODUCTION It is well known that the usual diss...

Compositional data are multivariate observations that carry only relative information. This means that not the absolute values but the ratios between the variables are of interest. This is important also for an exploratory analysis of such data. We present two basic methods for the exploratory compositional data analysis (ECDA), namely multivariate outlier detection and the compositional biplot...

Identification of sources of polycyclic aromatic hydrocarbons (PAH) in sediments is an important step in reducing anthropogenic contamination. Identifications based solely on the composition of PAH can be confounded by compositional changes during weathering and biodegradation. Stable isotopic composition of individual PAH offers an additional marker, which can aid in distinguishing sources and...

The chemical composition of honeys produced in Eastern and South-Eastern Anatolia (Turkey) was studied. For this aim, the composition of 45 honey samples collected from the mentioned regions and the effect of one year storage (20 ± 5oC) on the diastase activity and hydroxymethylfurfural (HMF) content were determined. Compositional data measured in the fresh honeys were HMF, diastase number, moi...