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Magnetic nanoparticles are efficient catalytic systems for various reactions because of their high efficiency and easy separation. Amongst magnetic nanoparticles, copper ferrite (CuFe2O4 NPs) is one of the different types of ferrites, which is widely used in catalytic reactions because of its magnetic properties. On the other hand, deep eutectic solvents (DESs) consisting of a hydrogen bond acceptor component and a hydrogen bond donor component have recently attracted the attention of many researchers as green solvents. ChCl-urea is considered a green DES that has been reported several times to carry out chemical reactions. In recent years, research on the synthesis of 2-thioaryl-benzothiazoles and 2-thioaryl-benzoxazoles (compounds containing C-S aryls and benzothiazoles and benzoxazoles scaffolds) has become an attractive challenge in organic chemistry. In this research, we report the synthesis of 2-thio-benzothiazoles and 2-thioaryl-benzoxazoles by CuFe2O4 NPs in ChCl-urea as an efficient nanocatalyst. These compounds were synthesized via a one-pot, three-component coupling reaction of benzoxazoles or benzothiazoles with aryl iodides and S8 as a sulfur source in the presence of KOAc as a base. [ABSTRACT FROM AUTHOR]

Research on synthetic methods for the preparation of oxazoles is an important issue among synthetic chemists because oxazole derivatives are structural subunits of various natural active products and are valuable synthetic and pharmaceutical precursors. In this research work, we constructed CuBr supported on surface of magnetic Fe3O4 nanoparticles modified with 6-(aminomethyl)nicotinic acid [Fe3O4@AMNA-CuBr nanocomposite] and evaluated its catalytic activity for the preparation of highly substituted oxazoles through one-pot three-component reactions of diphenylacetylene derivatives with aryl nitriles and water in PEG as the solvent. The results shown that the Fe3O4@AMNA-CuBr catalyst was used 8 times without significant decrease in catalytic activity. XRD and TEM analysis confirmed that the structure and morphology that the Fe3O4@AMNA-CuBr catalyst did not change after 8 runs. [ABSTRACT FROM AUTHOR]

Given that thermoelastic damping (TED) is one of the main causes of energy dissipation in miniaturized structures, calculation of its exact amount is of particular importance in the design of such elements. Considering three-dimensional (3D) heat transfer along with the scale effect on both mechanical and thermal areas is one of the decisive factors in the more rigorous modeling of TED in small-sized resonators. This paper exploits the modified couple stress theory (MCST) and dual-phase-lag (DPL) heat conduction model to establish an analytical TED relation for rectangular micro/nanoplate resonators with 3D heat conduction. At the start, the non-Fourier heat equation corresponding to 3D DPL model is derived. Then, the solution of temperature distribution is determined by employing infinite trigonometric series. Moreover, the scale-dependent frequency of the system is presented in the context of MCST. Eventually, with the help of entropy generation (EG) method, an analytical TED expression considering 3D heat conduction is established. The precision of the presented solution is examined by comparing it with a simpler model available in the literature. By choosing two common types of boundary conditions, i.e. fully-clamped (CCCC) and fully-simply (SSSS) supported plates, the influence of various factors on TED changes is comprehensively investigated in simulation section. According to the outcomes, in plates with a lower ratio of length and width to thickness, the dimension considered for heat conduction model has a noticeable impact on the variations of TED. [ABSTRACT FROM AUTHOR]

Imidazoles are one of the keys of N‐heterocycle molecules that exist in the structure of many biomolecules. In this research project, we reported that Fe3O4@BisImid−CuBr nanocomposite is an attractive and efficient nanomagnetic catalyst to afford 2,4,5–triaryl imidazoles through reactions of 1,2–diketones and aldehydes in the presence of NH4OAc under ecofriendly conditions. The Fe3O4@BisImid−CuBr nanocomposite was readily fabricated by a simple method from available reagents and its structure was analyzed by spectroscopic techniques. SEM and TEM images affirmed the formation of particles in spherical shape and nanometer–size. Under this methodology, a diverse library of triaryl imidazoles were afforded with high yields in water. This synthetic methodology has significant features such as (a) high yields and high purity of the products (b) suitable reaction time (c) use of magnetic reusable nanocatalyst (d) high reusability of Fe3O4@BisImid−CuBr nanocatalyst and the performance of reactions in aqueous medium. [ABSTRACT FROM AUTHOR]

This thorough review examines the latest developments in Metal-Organic Gels (MOGs), including their structure, properties, synthesis, and characterization methods. The scientific community is captivated by MOGs and their unique attributes, sparking interest and envisioning potential applications in various domains. This paper emphasizes the profound influence of synthetic parameters, including solvent choice, pH, concentration, temperature, reaction duration, and metal-to-ligand ratio, on the morphology, mechanical characteristics, kinetics, and overall optimization of MOGs. Understanding the fundamental mechanisms governing MOG formation and appreciating the pivotal role of synthetic conditions in tailoring their properties is imperative. Various synthetic strategies for MOG fabrication and a spectrum of characterization techniques are examined, offering insight into prospective applications. However, looking ahead, there is a clear need for a more organized approach to research, focusing on streamlining synthetic processes and advancing characterization methodologies. This will unlock the full potential of MOGs, propelling innovative and tailored properties for specific applications, thus driving the field towards a promising future. Consequently, this review underscores the urgency for sustained research efforts, envisioning a future where MOGs stand as versatile materials, reshaping the landscape of advanced materials and technologies. [ABSTRACT FROM AUTHOR]

Context: The potential of Ni-C72 and Ni-Al36P36 as effective catalysts for O3 decomposition is examined by LH and ER mechanisms. The activation barrier energy and Gibbs free energy of reaction steps for O3 decomposition on Ni-C72 and Ni-Al36P36 are calculated. The ∆Eformation of Ni-C72 and Ni-Al36P36 are negative values and these structures are stable nano-catalysts. The Ni atoms are catalytic positions to adsorb the O3 and other important species of O3 decomposition by LH and ER mechanisms. The Ni-Al36P36 for O3 decomposition has lower Eacivation and more negative ∆Greaction than Ni-C72. The Eacivation value of rate-determining step for O3 decomposition by LH mechanism is lower than ER mechanism. The Ni-C72 and Ni-Al36P36 can catalyze the reaction steps of O3 decomposition by LH and ER mechanisms. Methods: The structures of Ni-C72 and Ni-Al36P36 nanocages and their complexes with O3 and other important species of are optimized by PW91PW91/6–311 + G (2d, 2p) model and M06-2X/cc-pVQZ model in GAMESS software. The strcutures of nanocages and their complexes with important species of O3 decomposition by LH and ER mechanisms are optimized and their frequencies are calculated in order to demonstrate that these structures are real minima on the potential energy surface. [ABSTRACT FROM AUTHOR]

[Display omitted] • The nZVI were used for the removal of Zn, MB, and Pb from aqueous solution. • The effect of various factors on the amount of removal was evaluated by the RSM. • Removal of Zn, MB, and Pb significantly were accelerated under application of ultrasound. • Nitric acid was chosen as the optimum eluent among the different eluents. This work investigated the removal of zinc (Zn), methylene blue (MB), and lead (Pb) using nanosized zero-valent iron (nZVI). The analysis of variance (ANOVA) indicated that the second-order polynomial was a highly suitable model for removing pollutants. The specific surface area, pore diameter, and pore volume average of the nZVI were 16.4 m2 g−1, 40.1 Å, and 0.012 cm3 g−1, respectively. Under optimal conditions (pH = 7, concentration = 15 mg L−1, nZVI amount = 0.039 g, and ultrasound time = 10 min), the removal of Zn, MB, and Pb was 91.74 %, 95.60 %, and 95.16 %, respectively. The reusability study demonstrated that the nZVI can be utilized for 5 cycles of adsorption/desorption. In addition, nitric acid was selected as the optimum eluent among the different eluents. The analysis of environmental water samples revealed that the nZVI adsorbent has an acceptable ability to remove heavy metals and dyes from environmental water samples. [ABSTRACT FROM AUTHOR]

• Iodo-modification strategy turned out to be a general and versatile strategy for capturing multivalent chemical states of iodine. • This is the highest I 2 loading capacity recorded for MOFs in solution phase reported to date. • ZBPU-I 2 showed significant potential and highly selective application as a fluorescence probe for sensing iodide. • This study expands the MOFs design toolboxes for efficient I 2 / I͞ adsorption. Zr-based UiO-67(ZBPU) Metal-Organic Frameworks (MOFs) bearing iodo functional groups were synthesized, characterized, and then investigated for I 2 capture under solution and gaseous conditions. Consequently, mono- and bi-functional iodo-containing derivatives (ZBPU-I and ZBPU-I 2) exhibited remarkable performance compared to the pristine ZBPU, highlighting the versatility of halogen-halogen interactions in I 2 uptake. Notably, an iodine uptake capacity of 1260.7 mg.g−1 was recorded for ZBPU-I 2 in cyclohexane after 4 h, which is 3.8 times greater than the amount of non-modified ZBPU (329.25 mg.g−1). To the best of our knowledge, this is the highest I 2 loading capacity recorded for MOFs in solution phase. Moreover, ZBPU-I 2 illustrated reversible I 2 uptake and recyclability for four runs. Also, substantial enhancement for iodine vapor capture was observed by increasing the number of iodo functions: I 2 adsorptions of 2.6, 2.49, and 3.45 g.g−1 were measured for ZBPU, ZBPU-I and ZBPU-I 2 , respectively, further proving the effectiveness of MOFs iodo-functionalization strategy in I 2 adsorptive improvement. Besides I 2, ZBPU-I 2 showed significant potential and highly selective application as a fluorescence probe for sensing iodide (I͞). Correspondingly, ZBPU-I 2 responded to I͞ by completely overturning the emission spectra from turn-on mode to quenching mode even in the competing presence of various anions. Finally, this study expands the MOFs design toolboxes for efficient I 2 / I͞ adsorption. [Display omitted] [ABSTRACT FROM AUTHOR]

In this research, graphitic carbon nitride (g–C 3 N 4)–cobalt ferrite (CFO) and g–C 3 N 4 – Ca, Mg codoped CFO composite with and without ZnO nanoparticles were fabricated by a combination of hydrothermal and freeze-drying methods. The effects of CFO nanoparticles to graphitic carbon nitride (carbon azide or g-C 3 N 4) nanosheets weight ratio on the microstructure, phase evolution, magnetic, and electromagnetic (EM) behavior of g–C 3 N 4 – CFO–ZnO nanocomposite were investigated. The results revealed Ca-, and Mg-codoped CoFe 2 O 4 nanoparticles were obtained by the green synthesis method. Moreover , as-prepared g–C 3 N 4 – CFO–ZnO nanocomposite had lamella structures. The sample prepared with Ca-, Mg-codoped CFO: g-C 3 N 4 = 2:1 with an effective thickness of 10 mm absorbed more than 90% of EM waves in both the X-band (frequency 8.2–12.4 GHz) and Ku-band (12.4–18 GHz). Finally, the proposed mechanism of EM absorption was suggested. Finally, the effect of ZnO nanoparticles on the EM wave behavior of g–C 3 N 4 – CFO nanocomposite was investigated. [Display omitted] • Synthesis of carbon azide decorated with CFO and ZnO nanocomposite. • Green synthesized CFO nanoparticles increased total magnetization. • Green synthesized g–C 3 N 4 – CFO–ZnO nanocomposite improved EM reflection loss. [ABSTRACT FROM AUTHOR]

In this study, the catalytic activity and potential of Co-C 72 , Co-Si 72 and Co-Al 36 N 36 nanocages for Nitrogen reduction reaction (N 2 -RR) via distal, alternating, enzymatic and mixed mechanisms are investigated by theoretical methods. Results indicated that the *NN-Co-nanocage → *NNH-Co-nanocage step for Nitrogen reduction reaction (N 2 -RR) is limiting step on Co-C 72 , Co-Si 72 and Co-Al 36 N 36 nanocages. Results indicated that the ΔG reaction of N 2 -RR on Co-Al 36 N 36 nanocage via distal, alternating, enzymatic and mixed mechanisms are more negative than Co-C 72 and Co-Si 72 nanocages. Finally, the Co-Al 36 N 36 can be proposed as acceptable catalysts for N 2 -RR via distal, alternating, enzymatic and mixed mechanisms with high performance by theoretical methods. [Display omitted] • Potential of Co-C 72 , Co-Si 72 and Co-Al 36 N 36 for N 2 -RR by possible mechanism are investigated by theoretical methods. • Co atoms of Co-C 72 , Co-Si 72 and Co-Al 36 N 36 are catalytic sites to adsorb the N 2 molecules by theoretical methods. • Al 36 N 36 has higher ability and capacity than Co-C 72 and Co-Si 72 to adsorb N 2 molecule by theoretical methods. • Co-Si 72 and Al 36 N 36 nanocages are proposed as effective catalysts for N 2 -RR by theoretical methods. • Co-Si 72 and Co-Al 36 N 36 nanocages have lower over-potential than metal catalysts for N 2 -RR by theoretical methods. In this study, the catalytic activity and potential of Co-C 72 , Co-Si 72 and Co-Al 36 N 36 nanocages for Nitrogen reduction reaction (N 2 -RR) via various mechanisms are investigated by theoretical models. Results shown that the unoccupied 3d orbitals of electrons of Co atoms of Co-C 72 , Co-Si 72 and Co-Al 36 N 36 nanocages have high potential to adsorb the pair of valence electrons of Nitrogen molecule (N 2). Results indicated that the *NN → *NNH step for Nitrogen reduction reaction (N 2 -RR) is limiting step on Co-C 72 , Co-Si 72 and Co-Al 36 N 36 nanocages. The ΔG reaction of N 2 -RR on Co-Al 36 N 36 nanocage via distal, alternating, enzymatic and mixed mechanisms are more negative than Co-C 72 and Co-Si 72 nanocages. The Co-Al 36 N 36 nanocage is proposed as effective catalyst for N 2 -RR by theoretical models. [ABSTRACT FROM AUTHOR]