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Lanthanum is one of the rare earth metals which due to specific chemio-physical properties, has wide applications in different industries. In this research, the ability of the synthesized metal-organic framework (MOF), [Zn(bim)2(bdc)]n(ZBB) for the removal of lanthanum ions from the aqueous stream was investigated in the batch and column processes. The synthesized MOF was characterized by using scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The effect of pH on lanthanum ions adsorption was evaluated in the range from 1 to 7. Moreover, isothermal, kinetic, and thermodynamic parameters for adsorption of La(III) ions onto the synthesized MOF were evaluated. The adsorption capacity of lanthanum ions onto the synthesized MOF was calculated to be about 130 mg/g. Thermodynamic studies demonstrate the endothermic and chemical nature of lanthanum adsorption, while kinetic studies suggest the pseudo-first-order of reaction. In column mode, the effect of solution flow rate passing through the fixed-bed was studied. Experimental data confirm that increasing the bed flow rate causes a decrease in the adsorption capacity of lanthanum ions on the synthesized MOF.

Purpose: This qualitative study sought to explore how Iranian English language professors used social media network Telegram in their classes and what possibilities and constraints they experienced with regard to classroom interactions and university education, and how they rethought the use of social media network Telegram. Design/methodology/approach: Data were collected through written reflective exercises and semi-structured interviews. Furthermore, data were analyzed based on three moments of critical hermeneutics: a moment of social-historical analysis, a moment of formal analysis and a moment of interpretation-reinterpretation. Findings: The analysis of the data led to four themes: a dialogic classroom, the critical awareness of power-relations, the critical reflection on the experiences of the classroom and digital inequality. In fact, the participants pointed out that using social media network Telegram could lead to the persuasive discourse and multiplicity of voices as opportunities for sharing knowledge and distributing powers. Originality/value: Indeed, the present study addressed the learning processes resulted from using social media network Telegram rather than the product and outcome that were mainly addressed by the previous studies by considering three levels of descriptions, which included micro-level of the learner and teacher interaction, meso-level of the processes of educational institutions and macro-level of wider cultural and societal contexts.

Metal-organic frameworks (MOFs) are porous network compounds that result from the reaction between a transition metal and organic ligands. In this work, cesium ions were removed by the use of a synthesized MOF, zinc benzimidazole benzene dicarboxylic acid [Zn(bim)2(bdc)]n(ZBB) in aqueous solution. Removal of cesium ions occurred with an ion-exchange mechanism. Scanning electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, Brunauer–Emmett–Teller, and thermogravimetric analysis were used to characterize ZBB complex. Bach technique was used for adsorption experiments and the effect of pH, time, temperature, and adsorbent dosage were studied. The study of adsorption isotherms indicated that the sorption process best fits Langmuir isotherm. Radiation studies indicated that this synthesized MOF could be used in medium-active wastewaters treatment. The column experiments were also investigated in order to obtain the dynamic capacity of the adsorption process.

An aircraft crashing into a nuclear containment may induce a series of disasters related to containment capacity, including local penetration and perforation of the containment, intensive vibrations, and fire ignited after jet fuel leakage. In this study, structural safety of a reinforced concrete containment vessel (RCCV) has been studied against the direct hit of Airbus A320, Boeing 707-320 and Phantom F4 aircrafts. ABAQUS/explicit finite element code has been used to carry out the three-dimensional numerical simulations. The impact locations identified on the nuclear containment structure are mid height of containment, center of the cylindrical portion, junction of dome and cylinder, and over the cylindrical portion close to the foundation level. The loading of the aircraft has been assigned through the corresponding reaction-time response curve. The concrete damaged plasticity model was predicted to simulate the behavior of concrete while the behavior of steel reinforcement was incorporated using elastoplastic material model. Dynamic loading conditions were considered using dynamic increase factor. The mid height of containment and center of cylindrical portion have been found to experience most severe deformation against each aircraft crash. It has also been found that compression damage in concrete is not critical at none of the impact locations.

As one of multiple forms of literacy, art can cause human to achieve knowledge and insight. This subject can be studied as to various visions or approaches to art education. In this integrative inquiry, approaches of art education were studied and the results showed that the dominant approach in the current approved objectives is visual culture vision and in both the curriculum and syllabuses of art teacher training programs is art production approach. In the NC, thinking disposition, aesthetic, and DBAE approaches have been considered. Knowledge-domains in the current approved objectives for art education more relates to knowing that, and knowing howis more obvious in the curriculum and syllabuses of art teacher training, while The NC contains several knowledge kindsand approaches.