barium sulfate (barite) is one of the widely used weighting materials in the preparation of drilling fluid for deep oil and gas wells. barite is not soluble in the regular solvents; such as, hydrochloric acid (hcl) and other acids. therefore, in this study, we focused on evaluating the dissolution of the industrial barite particles in different chelating agents. chelating agents; such as, dieth...

Chitosan with excellent biodegradable and biocompatible characteristics has received attention as an oral drug delivery vehicle for controlled-release formulations. In this study an enteric-coated capsule containing theophylline-chitosan beads based on 23 factorial designs was prepared as a colon drug delivery system. The theophylline-chitosan gel beads were formulated by adding the drug-contai...

The properties of a variety of mouth protectors and sheet materials used to fabricate custom mouth protectors were determined in order to recommend limits for a specification. Hardness, water sorption, water solubility, impact absorption, and tear strength were measured, and limits for these properties were suggested.

The solubility of calcite in NaCl-H2O solutions was measured at 600–900 ∞C, 10 kbar, at NaCl concentrations ranging from dilute to near halite saturation, and at 6–14 kbar, 700 ∞C, in 30 mol% NaCl solutions. Solubility was determined from the weight loss of cleavage rhombs of a pure natural calcite after experiments of 1/2 to 6 days in a piston-cylinder apparatus with NaCl-graphite furnaces. Ca...

The oilfield water in the Upper Sandstone Member of the Zubair reservoir (Barriemian-Hauterivian) at Rumaila North Oil Field was investigated for the interpretation of salinity and geochemical evolution of brine compositions. The interaction of the oilfield water with reservoir rock resulted in a brine water derived from the marine water origin of partial mixing with meteoric water similar to t...

the simultaneous flow of oil and water in porous media is described by relative permeability curves, mainly derived from laboratory experiments. relative permeability is of paramount importance in predicting reservoir production performance and drive mechanisms and its value depends largely on the volume fraction of fluids present in the test samples. nowadays x-ray scanners are one of the most...

the quality of the river water is assessed in different months in different stations to evaluate the change in the quality in re1ation with the various point sources along the river. thirteen parameters were measured in the samples manually taken from three meters off shore in 20 cm. depth in four points representing the quality in four reaches under consideration. the results revealed that nat...

Urban-type PM 2.5-fraction aerosol samples were collected and samples of pure atmospheric humic-like substances (HULIS) were isolated from them. Atmospheric concentrations of organic carbon (OC), water soluble organic carbon (WSOC) and HULIS were determined, and UV/Vis spectroscopic properties, solubility and conductivity of HULIS in aqueous samples were investigated. Atmospheric concentrations...

Artemether (ARTM) is a very effective antimalarial drug with poor solubility and consequently low bioavailability. Smart nanocrystals of ARTM with particle size of 161±1.5 nm and polydispersity index of 0.172±0.01 were produced in <1 hour using a wet milling technology, Dena® DM-100. The crystallinity of the processed ARTM was confirmed using differential scanning calorimetry and powder X-ray d...

The design and development of processes involving supercritical fluids depend on how easy the phase equilibrium can be accurately modelled and predicted. In the work described herein, the supercritical fluid-solid equilibrium has been considered. Modelling the fluid-solid equilibrium is associated with a number of drawbacks, even when it is possible to obtain the experimental solubility data fo...