A Novel Equation of State: Determination and Validation for Dyes and Drugs Solubility Calculations in Supercritical Carbon Dioxide

Based on Pitzer correlations for the compressibility factor and virial equation of state, a new equation of state has been developed in this study, which is a function of total number of atoms present in the solute molecule, normal boiling point temperature and reduced temperature. Thirty dyes and sixty drugs solubility data, 2417 data points, have been collected from literature and compared with the Peng-Robinson EOS plus the two adjustable parameters van der Waals mixing rules, and the new proposed EOS. As the results show, the proposed EOS presents more accurate predictions for solubility data in Supercritical Carbon Dioxide

Correlation of shape and size of sella turcica with the type of facial skeletal class in an Iranian group

Background: In orthodontic science, diagnosis of facial skeletal type (class I, II, and III) is essential to make the correct treatment plan that is usually expensive and complicated. Sometimes results from analysis of lateral cephalometry radiographies are not enough to discriminate facial skeletal types. In this situation, knowledge about the relationship between the shape and size of the sella turcica and the type of facial skeletal class can help to make a more definitive decision for treatment plan. Objectives: The present study was designed to investigate this relationship in patients referred to a dental school in Iran. Patients and Methods: In this descriptive-analytical study, cephalometric radiographies of 90 candidates for orthodontic treatment (44 females and 46 males) with an age range of 14 - 26 years and equal distribution in terms of class I, class II, and class III facial skeletal classification were selected. The shape, length, diameter, and depth of the sella turcica were determined on the radiographs. Linear dimensions were assessed by one-way analysis of variance while the correlation between the dimensions and age was investigated using Pearson�s correlation coefficient. Results: Sella turcica had normal morphology in 24.4 of the patients while irregularity (notching) in the posterior part of the dorsum sella was observed in 15.6, double contour of sellar floor in 5.6, sella turcica bridge in 23.3, oblique anterior wall in 20 and pyramidal shape of the dorsum sella in 11.1 of the subjects. In total, 46.7 of class I patients had a normal shape of sella turcica, 23.3 of class II patients had an oblique anterior wall and a pyramidal shape of the dorsum sella, and 43.3 of class III individuals had sella turcica bridge (the greatest values). Sella turcica length was significantly greater in class III patients compared to class II and class I (P < 0.0001). However, depth and diameter of sella turcica were similar in class I, class II, and class III patients. Furthermore, age was significantly correlated to the diameter of sella turcica as greater diameters were observed in older ages (P < 0.04). Conclusion: A significant relationship exists between the type of facial skeletal classification and the shape of the sella turcica; as in class III patients, sella turcica bridge was reported with a higher frequency. Also, sella turcica had a significantly higher length in these patients than in those with class I and class II facial skeletal types. © 2015, Tehran University of Medical Sciences and Iranian Society of Radiology

A Novel Equation of State: Determination and Validation for Dyes and Drugs Solubility Calculations in Supercritical Carbon Dioxide

Based on Pitzer correlations for the compressibility factor and virial equation of state, a new equation of state has been developed in this study, which is a function of total number of atoms present in the solute molecule, normal boiling point temperature and reduced temperature. Thirty dyes and sixty drugs solubility data, 2417 data points, have been collected from literature and compared with the Peng-Robinson EOS plus the two adjustable parameters van der Waals mixing rules, and the new proposed EOS. As the results show, the proposed EOS presents more accurate predictions for solubility data in Supercritical Carbon Dioxide

The relationship between properties of plant-based biochars and sorption of Cd(II), Pb(II) and Zn(II) in soil model systems

Plant based biochars are proposed as soil amendments to immobilize potentially toxic trace elements (PTEs), such as Cd(II), Pb(II) and Zn(II) and aid in soil restoration. However, the sorption capacity of biochar for these elements can vary widely depending on biochar nature and metal properties. Currently, there is no clear methodology to pre-screen biochars for their suitability as adsorbents for these elements. Therefore, to facilitate biochar selection for application in soil restoration, this study explored the relationships between the physico-chemical properties of five plant-based biochars and their capacity to immobilize Cd(II), Pb(II) and Zn(II). Batch experiments using synthetic soil pore water were used to assess the sorption of these elements. The sorption isotherms described by the Hill model indicated that PTE sorption capacity followed the order Pb(II) > Cd(II) >Zn(II) regardless of biochar type in mono-element systems. Preferential sorption of Pb(II) limited the immobilization of Cd(II) and Zn(II) in multi-element systems. ATR-FTIR and SEM-EDX spectroscopy studies indicated that Cd(II) and Pb(II) sorption was mediated by complexation with carboxylic groups, cation–π interactions and precipitation with phosphates and silicates, while Zn(II) sorption occurred mainly by complexation with phenolic groups and precipitation with phosphates. A high correlation (>0.8) between Electrical Conductivity, Cation Exchange Capacity, pH and sorption capacity was identified for all metals tested, highlighting the electrostatic nature of the sorption mechanisms involved. Biochars derived from herbaceous feedstock were better candidates for remediation of soil polluted with Cd(II), Pb(II) and Zn(II), rather than wood-derived biochar. Overall, this study provides evidence of the direct relationship between specific properties of plant-based biochars (pH and EC) and their suitability as adsorbents for some PTEs in soil systems

Correlation of Shape and Size of Sella Turcica With the Type of Facial Skeletal Class in an Iranian Group

BACKGROUND: In orthodontic science, diagnosis of facial skeletal type (class I, II, and III) is essential to make the correct treatment plan that is usually expensive and complicated. Sometimes results from analysis of lateral cephalometry radiographies are not enough to discriminate facial skeletal types. In this situation, knowledge about the relationship between the shape and size of the sella turcica and the type of facial skeletal class can help to make a more definitive decision for treatment plan. OBJECTIVES: The present study was designed to investigate this relationship in patients referred to a dental school in Iran. PATIENTS AND METHODS: In this descriptive-analytical study, cephalometric radiographies of 90 candidates for orthodontic treatment (44 females and 46 males) with an age range of 14 - 26 years and equal distribution in terms of class I, class II, and class III facial skeletal classification were selected. The shape, length, diameter, and depth of the sella turcica were determined on the radiographs. Linear dimensions were assessed by one-way analysis of variance while the correlation between the dimensions and age was investigated using Pearson's correlation coefficient. RESULTS: Sella turcica had normal morphology in 24.4% of the patients while irregularity (notching) in the posterior part of the dorsum sella was observed in 15.6%, double contour of sellar floor in 5.6%, sella turcica bridge in 23.3%, oblique anterior wall in 20% and pyramidal shape of the dorsum sella in 11.1% of the subjects. In total, 46.7% of class I patients had a normal shape of sella turcica, 23.3% of class II patients had an oblique anterior wall and a pyramidal shape of the dorsum sella, and 43.3% of class III individuals had sella turcica bridge (the greatest values). Sella turcica length was significantly greater in class III patients compared to class II and class I (P < 0.0001). However, depth and diameter of sella turcica were similar in class I, class II, and class III patients. Furthermore, age was significantly correlated to the diameter of sella turcica as greater diameters were observed in older ages (P < 0.04). CONCLUSION: A significant relationship exists between the type of facial skeletal classification and the shape of the sella turcica; as in class III patients, sella turcica bridge was reported with a higher frequency. Also, sella turcica had a significantly higher length in these patients than in those with class I and class II facial skeletal types