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Abstract Washing crude epoxidized oil is an indispensable step for the removal of residual acetic acid and unreacted hydrogen peroxide after epoxidation. There are many studies on the epoxidation of vegetable oils but there are many discrepancies in the washing process which likely leads to water wastage, excess use of neutralizing agent, and additional processing time. Hence, this study aims to optimize the washing step by analyzing the quality of each washing step and developing a model that can predict the amount of acid removed. Soybean oil (1.5 kg) was epoxidized at 60°C for 5.5 h using Amberlite IR 120H as a heterogeneous catalyst. To determine the optimum water washing level, process parameters such as number of washing cycles (1–5), proportion of epoxidized oil to water volume (1:0.5, 1:1, 1:2, 1:3, 1:4, 1:5), and water temperature (20, 40, and 60°C) were examined. The main responses were the residual acid value and pH of the washed epoxidized oil. Results revealed that 64% of the acid was removed after 5 washing cycles irrespective of the washing water temperature and proportion. In contrast, approximately 57% of the acid was removed in the first two washing cycles. Increasing the temperature of the water affected acid removal; with approximately 54% of acid removed at 20°C compared to 60% at 60°C. Doubling or tripling the amount of water needed above a 1:0.5 ratio did not significantly affect the amount of acid removed. The model developed was significant with a predictedR²of 96% and a root mean square error (RMSE) of 1.1 when the model was validated at different washing scenarios. Therefore, this study shows that it is possible to significantly reduce the amount of water used and processing time while maintaining resin qualities. 

In this study, we investigate the utility of Ca₂FeMnO_6-δand Sr₂FeMnO_6-δas materials with low thermal conductivity, finding potential applications in thermoelectrics, electronics, solar devices, and gas turbines for land and aerospace use. These compounds, characterized as oxygen-deficient perovskites, feature distinct vacancy arrangements. Ca₂FeMnO_6-δadopts a brownmillerite-type orthorhombic structure with ordered vacancy arrangement, while Sr₂FeMnO_6-δadopts a perovskite cubic structure with disordered vacancy distribution. Notably, both compounds exhibit remarkably low thermal conductivity, measuring below 0.50 Wm⁻¹K⁻¹. This places them among the materials with the lowest thermal conductivity reported for perovskites. The observed low thermal conductivity is attributed to oxygen vacancies and phonon scattering. Interestingly as SEM images show the smaller grain size, our findings suggest that creating vacancies and lowering the grain size or increasing the grain boundaries play a crucial role in achieving such low thermal conductivity values. This characteristic enhances the potential of these materials for applications where efficient heat dissipation, safety, and equipment longevity are paramount. 

The thermal conductivity of CaSrFe2O6-δ, an oxygen-deficient perovskite, is a critical parameter for understanding its thermal transport properties and potential applications in energy conversion and electronic devices. In this study, we present an investigation of the thermal conductivity of CaSrFe2O6-δ at room temperature for its thermal insulation property study. Experimental measurement was conducted using a state-of-the-art thermal characterization technique, Thermtest thermal conductivity meter. The thermal conductivity of CaSrFe2O6-δ was found to be 0.574W/m/K, exhibiting a notable thermal insulation property. 

Materials with low thermal conductivity have been used in thermoelectrics, electronics, solar devices, and land base and aerospace gas turbines to prevent heat dissipation and provide safety and longevity of equipment. We report Ca2Fe2O6-δ, and Sr2Fe2O6-δ for their low thermal conductivities. These compounds are vacancy-ordered oxygen-deficient perovskites but with different vacancy arrangements. Ca2Fe2O6-δ has a brownmillerite type structure while Sr2Fe2O6-δ has a different structure. 

Today’s data-driven world requires earth and environmental scientists to have skills at the intersection of domain and data science. These skills are imperative to harness information contained in a growing volume of complex data to solve the world's most pressing environmental challenges. Despite the importance of these skills, Earth and Environmental Data Science (EDS) training is not equally accessible, contributing to a lack of diversity in the field. This creates a critical need for EDS training opportunities designed specifically for underrepresented groups. In response, we designed the Earth Data Science Corps (EDSC) which couples a paid internship for undergraduate students with faculty training to build capacity to teach and learn EDS using Python at smaller Minority Serving Institutions. EDSC participants are further empowered to teach these skills at their home institutions which scales the program beyond the training lead by our team. Using a Rasch modeling approach, we found that participating in the EDSC program had a significant impact on learners’ comfort and confidence with technical and non-technical data science skills, as well as their science identity and sense of belonging in science, two critical aspects of recruiting and retaining members of underrepresented groups in STEM. 

The crystal structure of CaSrFe0.75Co0.75Mn0.5O6−δ is investigated through neutron diffraction techniques in this study. The material is synthesized using a solid-state synthesis method at a temperature of 1200˚C. Neutron diffraction data is subjected to Rietveld refinement, and a comparative analysis with X-ray diffraction (XRD) data is performed to unravel the structural details of the material. The findings reveal that the synthesized material exhibits a cubic crystal structure with a Pm-3m phase. The neutron diffraction results offer valuable insights into the arrangement of atoms within the lattice, contributing to a comprehensive understanding of the material’s structural properties. This research enhances our knowledge of CaSrFe0.75Co0.75Mn0.5O6−δ, with potential implications for its applications in various technological and scientific domains. 

This study introduces a novel oxygen-deficient perovskite, Sr2Fe0.75Co0.75Mn0.5O6-δ, synthesized through a solid-state reaction and thoroughly characterized by Powder XRD, SEM and direct current (DC) electrical conductivity measurements. The material, exhibiting a cubic crystal structure with the Pm3̅m space group, demonstrates intriguing electrical properties. At temperatures ranging from 25 to 400 °C, the material displays semiconductor-type conductivity, transitioning seamlessly to metallic-type conductivity from 400 to 800 °C. The deliberate incorporation of cobalt into the perovskite structure is found to be pivotal, as evidenced by a comparative analysis with its parent compound, Sr2FeMnO6-δ. This investigation reveals a substantial improvement in electrical conductivity, underscoring the significance of the partial substitution of cobalt. The tailored electrical properties of Sr2Fe0.75Co0.75Mn0.5O6-δ position it as a versatile candidate for electronic applications. 

We find an exact closed-form expression for the magnetostatic interaction energy between a point magnet and a ring magnet in terms of complete elliptic integrals. The exact expression for the energy exhibits an equilibrium point close to the axis of symmetry of the ring magnet. Our methodology will be useful in investigations concerning magnetic levitation, and in the study of Casimir levitation.