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Responsive root traits and mitigating strategies for wheat production under single or combined abiotic stress
No full textSecondary inorganic aerosols and aerosol acidity at different PM2.5 pollution levels during winter haze episodes in the Sichuan Basin, China
No full textSublimation rate of solid NaCl powders and evaporation rate of liquid NaCl upon heating in vacuum and air
No full textSi/Graphite Anodes for Solid-State Batteries: Composition Selection via Electrochemical and Chemo-Mechanical Properties
No full textSilicon–graphite composites are among the most widely used anode materials in conventional lithium-ion batteries and recently have been considered as promising candidates in lithium-ion solid-state batteries. In this work, we investigate the influence of the silicon content on the electrochemical and chemo-mechanical behaviors of different Si/graphite composites in solid-state batteries. All anode composites show that an increase of Si presence in the composite enhances the cyclability at a high current density. Using direct-current (DC) polarization and temperature-dependent electrochemical impedance spectroscopy, we observe that both electronic and ionic conductivities are sufficient across the composition series. Operando stress measurements demonstrate how the internal pressure of the anode in a solid-state battery changes as a function of the Si content. Less Si (e.g., ≤10 wt %) in the blended matrix offers smaller internal stress, while it is significantly increased at 20 wt % of Si. This study emphasizes the importance of optimizing the silicon/graphite ratio in the anode composites to balance high battery performance with stable chemo-mechanical propertie
Large-scale resource assessments for solar photovoltaics: A review of potential definitions, methodologies and future research needs
No full textRe-evaluating 2-heptanol as solvent for the extraction of 2,3-butanediol from water
No full textThe performance of an extraction-distillation process for separating 2,3-butanediol from H2O was evaluated in a recent study, finding high efficeincy when using 2-heptanol as solvent for extraction. Since the study was based on liquid-liquid equilibrium (LLE) data mainly derived from molecular simulations, the aim of this communication was to consolidate the database by providing experimental phase equilibrium data and to re-evaluate 2-heptanol as solvent. Based on LLE experiments, a solvent-to-feed ratio (S/F) of 3.175 was required to recover 95 % of 2,3-BDO in a counter-current extraction column. This S/F is 21.9 times higher than the estimation derived from the data based on molecular simulations. The high S/F results in a strong dilution of 2,3-BDO in the extract. Experimental investigation of the boiling point data of the 2,3-BDO – 2-heptanol system for subsequent distillation revealed the presence of a temperature minimum azeotrope at low 2,3-BDO concentrations, which limits the feasibility of the overall process. Since the use of 2-heptanol as solvent is oftentimes referred to in the community of diol separation, the results presented in the work at hand are relevant to a broad readership
Terpenoids as solvents for the separation of 2,3-butanediol from water: Phase equilibria and process evaluation
No full text2,3-butanediol (2,3-BDO) is a versatile platform chemical that can be produced via fermentation in aqueous solution. The energy intensive recovery of the high boiling 2,3-BDO from water via distillation hinders the economic viability of biotechnological produced 2,3-BDO. Hence, extraction-distillation processes using novel solvents from the class of terpenoids, namely menthol, thymol, and carvacrol, are proposed. To this end, binary and ternary liquid-liquid equilibrium (LLE) data for H2O, 2,3-BDO, and each terpenoid, as well as boiling point data for 2,3-BDO and the respective terpenoid, are measured. The thermodynamic phase equilibria are correlated with the non-random two liquid (NRTL) model and consecutive process design of the extraction-distillation processes is conducted using Aspen Plus. Conventional solvents (isobutanol, 1-butanol, and oleylalcohol), thymol, and carvacrol are assessed in terms of specific exergy demand for the production of 2,3-BDO. The lowest specific exergy demands were found for oleyl alcohol (5.38 kJ g−1) and thymol (5.14 kJ g−1), carvacrol (5.49 kJ g−1). Hence, terpenoids are a competitive class of solvents and should be included in solvent screening approaches
