Orientational Effects and Random Mixing in 1‑Alkanol + Nitrile Mixtures

1-Alkanol + alkanenitrile or + benzonitrile systems have been investigated by means of the molar excess functionsenthalpies (Hm E ), isobaric heat capacities (Cp,m E ), volumes (Vm E ), and entropiesand using the Flory model and the concentration−concentration structure factor (SCC(0)) formalism. From the analysis of the experimental data available in the literature, it is concluded that interactions are mainly of dipolar type. In addition, large Hm E values contrast with rather low Vm E values, indicating the existence of strong structural effects. Hm E measurements have been used to evaluate the enthalpy of the hydroxyl−nitrile interactions (ΔHOH−CN). They are stronger in methanol systems and become weaker when the alcohol size increases. In solutions with a given short chain 1-alkanol (up to 1-butanol), the replacement of ethanenitrile by butanenitrile weakens the mentioned interactions. Application of the Flory model shows that orientational effects exist in methanol or 1- nonanol, or 1-decanol + ethanenitrile mixtures. In the former solution, this is due to the existence of interactions between unlike molecules. For mixtures including 1-nonanol or 1-decanol, the systems at 298.15 K are close to their UCST (upper critical solution temperature), and interactions between like molecules are dominant. Orientational effects also are encountered in methanol or ethanol + butanenitrile mixtures because self-association of the alcohol plays a more important role. Aromaticity effect seems to enhance orientational effects. For the remainder of the systems under consideration, the random mixing hypothesis is attained to a rather large extent. Results from the application of the SCC(0) formalism show that homocoordination is the dominant trend in the investigated solutions, and are consistent with those obtained from the Flory model

The Prevalence of Irritable Bowel Syndrome Symptoms in High School Students in Abadan City in 2016

Background and Purpose: Irritable bowel syndrome (IBS) is a chronic functional bowel disorder that is thought to be due to a disorder of brain-gut function and a chronic and debilitating functional gastrointestinal disorder that affects 9-23 of the population across the world. This problem (IBS) is the second cause of absenteeism from the work and school, too. There is classification system for IBS (Rome IV classification system). Method: The purpose of this descriptive cross-sectional study was determination Prevalence of Irritable Bowel Syndrome Symptoms in High School female Students in Abadan City in 2016. In this study, using a two-part questionnaire designed by the researcher, one part of which was demographic information, and the second part was IBS symptoms, 1044 girls were classified using random sampling method. After collecting data, data were analyzed by SPSS software version 19 and descriptive statistics tests. P value less than 0.05 was considered significant. Findings: The age range of participants was between the ages of 14 and 18 and their mean age was 16 +/- 2. The findings of this study showed that the most common symptoms of IBS include abdominal pain (66.4), diarrhea (46.7), constipation (42.5). Conclusion: According to the results of the study, it can be said that the symptoms of IBS are high among high school female students, thus clarifying the need for more attention to this issue