An Agilent Simulated Distillation (SIMDIS) system is described for quality control and monitoring of refinery processes. The system uses an Agilent 6890N gas chromatograph (GC) equipped with a programmable temperature vaporizer (PTV) inlet designed specifically for high temperature analysis. A simulated distillation software program that couples with the Agilent GC ChemStation provides an easy-...

Background/Aims Gastroesophageal reflux disease (GERD) is the most common cause of non-cardiac chest pain (NCCP). Currently available data reveal a weak relationship between NCCP and dysmotility. Moreover, it is unclear why some refluxes are perceived as heartburn and others as NCCP. We aimed to evaluate the role of the reflux pattern and the esophageal motility in patients with NCCP. Methods...

Water enriched with its natural isotopes plays an important role in research and technology. Heavy water (HDO, D2O) is used in nuclear technology and research and the increasing market demand is expected in future if nuclear fusion will be used for energy production. Water enriched in O is used in research and medicine in trace experiments, as is water enriched in O. Recently there appears to b...

This paper proposes the simultaneous integration of environmentally benign solvent selection (chemical synthesis), solvent recycling (process synthesis) and optimal control for the separation of azeotropic systems using batch distillation. The previous work performed by Kim et al. (2004) combines the chemical synthesis and process synthesis under uncertainty. For batch distillation, optimal ope...

The barrier function of the esophageal epithelium is a major defense against gastroesophageal reflux disease. Previous studies have shown that reflux damage is reflected in a decrease in transepithelial electrical resistance associated with tight junction alterations in the esophageal epithelium. To develop novel therapies, it is critical to understand the molecular mechanisms whereby contact w...

In this article the methodology proposed by Li and Wang for mixed qualitative and quantitative modeling and simulation of temporal behavior of processing unit is reexamined and extended to more complex case. The main issue of their approach considers the multivariate statistics of principal component analysis (PCA), along with clustered fuzzy digraphs and reasoning. The PCA and fuz...

A realistic numerical model is used to study the circulation and mixing of Salish Sea, a large, complex estuarine system on United States Canadian west coast. The Sea biologically productive supports many important fisheries but threatened by recurrent hypoxia ocean acidification, so clear understanding its patterns residence times value. exchange flow quantified at 39 sections over 3 years (20...

in this article the methodology proposed by li and wang for mixed qualitative and quantitative modeling and simulation of temporal behavior of processing unit is reexamined and extended to more complex case. the main issue of their approach considers the multivariate statistics of principal component analysis (pca), along with clustered fuzzy digraphs and reasoning. the pca and fuzzy clustering...

CONTEXT In infants, it is not always easy to distinguish between pathological and physiological gastroesophageal reflux based only on clinical criteria. In Brazil, studies about gastroesophageal reflux disease in infants are few and are even rare those that used prolonged esophageal pH monitoring for its evaluation. OBJECTIVE To describe the clinical features of gastroesophageal reflux diseas...

Esophageal pH monitoring is considered the gold standard for the diagnosis of gastroesophageal reflux disease because of the normal ranges across the pediatric age range. However, this method can only detect acid reflux. Multichannel intraluminal impedance-pH (MII-pH) monitoring has recently been used for the detection of bolus reflux in infants and children. This method allows for the detectio...