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A simple, efficient and quick salting-out based centrifugeless dispersive liquid-liquid microextraction combined with high-performance liquid chromatography-ultraviolet detection (HPLC-UV) has been successfully developed for the determination of selected parabens in environmental water samples. Herein, following the dispersion of the extracting solvent (1-undecanol) whose melting point is near the room temperature into the sample solution, the cloudy mixture is passed through a test tube filled with sodium chloride, acting as separating agent based on salting-out phenomenon. By immersing the tube inside an ice bath, the fine droplets of the extraction solvent are solidified, easily collected and after returning to the liquid state, injected into HPLC-UV. The values of the detection limit were in the range of 2.5-5.0 µg L-1 while the intra-day (n = 7) and inter-day (n = 9, within three days) precision were below 3.7 and 4.7%, respectively. A satisfactory linearity (0.997 ≥ r2 ≥ 0.996) and quite a broad linear range (5.0-250 µg L-1) were achieved. The relative errors as the accuracy were less than 6.4% in all experiments. The method was eventually employed for the preconcentration and determination of the analytes in various natural water samples and acceptable results were achieved.

This systematic review followed the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. The primary aim of this research was to identify risks and protective factors for the mental health of forced migrants. The secondary aim was to suggest an alternative, more comprehensive approach in social work that surpasses usual diagnoses and intrinsically contradicts the medicalization of mental health issues of forced migrants. The search was conducted between January 2015 and January 2021. As a result, 29 studies met inclusion criteria. Medicalizing mental health issues by relying solely on the effectiveness of medicine was a controversial risk factor that negatively affected daily life activities of refugees and reduced their willingness for seeking professional mental health services. Empowering vulnerable minorities by giving them back their power and agency to be able to speak for themselves and raise voices of trauma and recovery was the missing protective factor for a sustainable mental health practice. The benefits of group-based interventions were highlighted in which communities and individuals address mental health issues as well as isolation through building collective identities and support networks. Information and communication technologies (ICTs) can add more strength to any kind of mental health interventions. Finally, the benefits of applying an ecological perspective for the study of the mental health of refugees, and its implications for a sustainable intercultural practice, were discussed. Social workers in this model are the representatives of at-risk groups, and thus require more agency and creativity in reflecting client’s concrete needs.

Quantitative structure–reactivity relationship (QSRR) can be considered as a variant of quantitative structure property relationship (QSPR) studies, where the chemical reactivity of reactants in a specified chemical reaction is related to chemical structure. As follows, the sulfonation reaction yield of 24 amines, alcohols and phenols with sulfonyl chloride was studied by QSRR. Quantum chemical calculations (b3lyp/6-31+g (d)) were carried out to obtain the optimized geometry. The suitable set of molecular descriptors was calculated to represent the molecular structures of compounds, such as constitutional, topological, geometrical, electrostatic and quantum-chemical descriptors. The genetic algorithm (GA) was applied to select the variables that resulted in the best-fitted models. After the variable selection, multiple linear regression (MLR) was utilized to construct linear QSRR models. The maximum relative error in prediction (5.26) showed that the predictive ability of the model was satisfactory and it can be used for designing similar reactants with efficient sulfonation reaction.

Mercury is a toxic metal, without biological effect in human body and causes CNS and renal disease. So, removal of mercury vapor through sorbents is an important environmental problem. Due to high capability of nano particle sorbents, nano particle palladium modified on multi wall carbon nano tube (NPd-MWCNT) and single wall carbon nano tube(SWCNT) were selected for this investigation. In this study, instrumental conditions, method procedure and different effect parameters such as, absorption and adsorption efficiency, absorption capacity, temperature, time and repeatability were studied and optimized. In addition the efficiency of sorbents was compared. Absorption capacity and efficiency of sorbents depend on the amount of sorbent, kind of nano particle and mercury mass concentration. For 80 mg of sorbents, working range of NPd-MWCNT and SWCNT were achieved 0.01-3 μg and 0.02- 0.7 μg respectively. Limit of detection (LOD) of NPd-MWCNT (0.003 μg) and SWCNT (0.006 μg) were obtained. In this research, mercury vapor was determined and produced by cold vapor atomic absorption spectrometry (CV-AAS) and mercury pilot respectively. The results show us, the maximum absorption capacity of NPd-MWCNT (8 μg g-1) was higher than SWCNT (0.5 μg g-1) and NPd-MWCNT that had high potential mercury removal.