[BMIM][PF6] Incorporation Doubles CO2 Selectivity of ZIF-8: Elucidation of Interactions and Their Consequences on Performance.

Experiments were combined with atomically detailed simulations and density functional theory (DFT) calculations to understand the effect of incorporation of an ionic liquid (IL), 1-n-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]), into a metal organic framework (MOF with a zeolitic imidazolate framework), ZIF-8, on the CO2 separation performance. The interactions between [BMIM][PF6] and ZIF-8 were examined in deep detail, and their consequences on CO2/CH4, CO2/N2, and CH4/N2 separation have been elucidated by using experimental measurements complemented by DFT calculations and atomically detailed simulations. Results suggest that IL-MOF interactions strongly affect the gas affinity of materials at low pressure, whereas available pore volume plays a key role for gas adsorption at high pressures. Direct interactions between IL and MOF lead to at least a doubling of CO2/CH4 and CO2/N2 selectivities of ZIF-8. These results provide opportunities for rational design and development of IL-incorporated MOFs with exceptional selectivity for target gas separation applications.

Thermal Stability Limits of Imidazolium Ionic Liquids Immobilized on Metal-Oxides.

Thermal stability limits of 33 imidazolium ionic liquids (ILs) immobilized on three of the most commonly used high surface area metal-oxides, SiO2, γ-Al2O3, and MgO, were investigated. ILs were chosen from a family of 13 cations and 18 anions. Results show that the acidity of C2H of an imidazolium ring is one of the key factors controlling the thermal stability. An increase in C2H bonding strength of ILs leads to an increase in their stability limits accompanied by a decrease in interionic energy. Systematic changes in IL structure, such as changes in electronic structure and size of anion/cation, methylation on C2 site, and substitution of alkyl groups on the imidazolium ring with functional groups have significant effects on thermal stability limits. Furthermore, thermal stability limits of ILs are influenced strongly by acidic character of the metal-oxide surface. Generally, as the point of zero charge (PZC) of the metal-oxide increases from SiO2 to MgO, the interactions of IL and metal-oxide dominate over interionic interactions, and metal-oxide becomes the significant factor controlling the stability limits. However, thermal stability limits of some ILs show the opposite trend, as the chemical activities of the cation functional group or the electron donating properties of the anion alter IL/metal-oxide interactions. Results presented here can help in choosing the most suitable ILs for materials involving ILs supported on metal-oxides, such as for supported ionic liquid membranes (SILM) in separation applications or for solid catalyst with ionic liquid layer (SCILL) and supported ionic liquid phase (SILP) catalysts in catalysis.

Suicidal ideation in patients with obsessive-compulsive disorder.

The risk factors for suicidal behaviour in obsessive-compulsive disorder (OCD) have been less studied compared than in other anxiety disorders. In the present study, we examined the demographic and clinical correlates of current suicidal ideation (SI) in patients with OCD. Forty-four patients were grouped into those with (n=23) and without current SI (n=21) as assessed by the Scale for Suicidal Ideation. The Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) was used to assess the obsessive-compulsive (OC) symptomatology. Following Bonferroni correction, only the severity of depression differed significantly between the two groups. The presence of major depression and aggressive obsessions, the level of hopelessness, and the severity of OC symptomatology were significant predictors of current SI in patients with OCD. The relatively low frequency of some comorbid Axis I disorders is based on small sample size and therefore may be vulnerable to type II error. We did not examine the relationship between the recent suicidal attempts and OCD. Also, we did not assess the effect of impulsivity in the occurrence of SI in patients with OCD. Associated depression, hopelessness, and aggressive obsessions might play an important role in the occurrence of SI in patients with OCD. However, future studies with a psychological autopsy design are required to systematically determine the presence for OCD among those who have completed suicide.

[Plate fixation of closed femoral shaft fractures in adolescents]. / Adölesan kapali femur cisim kiriklarinin tedavisinde plak ve vida ile osteosentez.

OBJECTIVES: This study was designed to evaluate the results, advantages, and disadvantages of plate fixation of closed femoral shaft fractures in adolescents between the ages of 11 and 15 years. METHODS: The study included 35 adolescents (26 males, 9 females; mean age 13.4 years) who were treated by plate fixation for closed femoral shaft fractures and had an adequate follow-up. The fractures were bilateral in two patients, on the left in 17 patients (48%), and on the right in 16 patients (45%). Traffic accidents were the most frequent etiology (57%). Nineteen patients presented with head injuries and/or multiple fractures. The mean follow-up was 34.9 months (range 22 to 156 months). RESULTS: All fractures healed in a mean of 10 weeks (range 6 to 16 weeks). No plate break or refractures occurred. Two patients had a loss of 20 degrees in knee flexion. Atrophy of the quadriceps muscle was observed in nine patients. Evaluations with the use of scanogram, orthorontgenogram, plain radiographs, and clinical examination showed an average overgrowth of 1.2 cm (range 0.4 to 1.6 cm). CONCLUSION: Despite some disadvantages, plate fixation seems to be an alternative method in the treatment of adolescent femoral fractures, enabling an anatomical reduction and stable internal fixation.