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Single ion conducting gel polymer electrolytes (GPEs) are characterized as having a certain amount of ionic liquid or solvent incorporated into a single ion-conducting polymer matrix and may afford the advantages of high conductivity and low electrolyte polarization under battery operation. Single ion conducting polymers often suffer from low conductivity due to their reliance on polymer segmental motion to achieve sufficient ion mobility. However, by incorporating specific solvents into a single ion conducting matrix, mobility of the polymer can be enhanced while still maintaining the advantages of single ion conduction. Although many of the solvents used to swell GPEs are mixtures of flammable organic solvents (such as dimethyl carbonate), there are many potential non-reactive, low vapor pressure solvents that could effectively solvate alkali-ion based GPEs and plasticize the polymer matrix to enhance ion conductivity. Adipate-based solvents are a group of non-volatile plasticizers with low viscosities and low vapor pressures at room temperature derived from adipic acid. The ester groups in these solvents may effectively solvate alkali ions such as Na+, leading to higher conductivity, while circumventing issues of flammability found in current alkali-ion conducting electrolytes. This study investigates the properties of sodium-ion conducting GPEs that have been swollen with varying adipate-based solvents and the subsequent dielectric response from the solvent addition. Dielectric relaxation spectroscopy was used to characterize the Na+ conductivity, static dielectric constant, ion-conducting content, and mobility of the membranes before and after the non-volatile solvent uptake. Understanding this relationship will pave the path toward safer, more efff cient solid-state polymer electrolytes for battery applications. [ABSTRACT FROM AUTHOR]

Teaching hydrogen bridges (H-bridges) in introductory chemistry courses is either oversimplified or dogmatically taught; the heuristic that 'only fluorine, oxygen and nitrogen (FON) form H-bridges' is commonly used, for example. This rule limits choices, does not match reality, and does not clarify the difference between H-bridge donors (HBD) and H-bridge acceptors (HBA) nor intermolecular versus intramolecular cases. Hydrogen fluoride is a significant HBD but a poor HBA. Oxygen is not always an HBD or HBA. Ammonia is a significant HBA but a poor HBD. There are many examples of H-bridges that do not contain these three elements. All examples of H-bridges should be shown in a way to provide symbolic and molecular structures. Is it necessary to 'explain' H-bridges in introductory classes? We conclude not, but it might be necessary to increase the total amount of time to present the material so that students do not rely on superficial rules. [ABSTRACT FROM AUTHOR]

New data are obtained on the thermal behavior and processes of vaporization and melting of (hexafluoroacetylacetonato)(cyclooctadiene-1,5)silver, [Ag(cod)(hfac)]n (n = 1, 2). The dimeric form of the complex is synthesized and characterized. The condensed phase is studied via differential scanning calorimetry plus thermogravimetric and differential thermal analysis. The thermal stability and qualitative volatility are assessed, and the temperature, enthalpy, and entropy of melting are determined for the complex. It is shown that the compound is highly sensitive to heating, preventing the experimental determination of reliable thermodynamic characteristics. Thermodynamic characteristics of the evaporation of these chelates are calculated using standardized values of enthalpies and entropies of the sublimation and melting of similar heteroligand complexes of copper(I) and iridium(I). The data are used to construct structure–volatility correlations that allow estimates of the required phase transitions of the target silver complex. An approach to evaluating the thermodynamic properties of complexes of the composition [M(cod)(β-dik)]n is proposed to determine the optimum conditions for depositing coatings that contain metal. [ABSTRACT FROM AUTHOR]

Aminomethanol is released into the atmosphere through various sources, including biomass burning. In this study, we have expounded the chemical kinetics of aminomethanol in the reaction pathways initiated by the hydroxyl radical (OH) with the aid of ab /n/t/o//density functional theory (DFT) i.e., coupled-cluster theory (CCSD(T))//hybrid-DFT (M06-2X/6-311++G (3df, 3pd). We have explored various possible directions of the OH radical on aminomethanol, as well as the formation of distinct pre-reactive complexes. Our computational findings reveal that the H transfer necessitates activation energies ranging from 4.1 to 6.5 kcal/mol from the -CH2 group, 3.5-6.5 kcal/mol from the -NH2 group and 7-9.3 kcal/mol from the -OH group of three rotational conformers. The H transfer from -CH2, -NH2 and -OH exhibits an estimated total rate constant (kOH) of approximately 1.97 x 10-11cm3 molecule-1 s-1 at 300 K. The branching fraction analysis indicates a pronounced dominance of C-centered NH2CHOH radicals with a favorability of 77%, surpassing the N-centered N HCH2OH (20%) and O-centered NH2CH2O (3%) radicals. Moreover, our investigation delves into the oxidation of the prominently favored carbon-centered NH2CHOH radical through its interaction with atmospheric oxygen molecules. Intriguingly, our findings reveal that formamide (NH2CHO) emerges as the predominant product in the NH2CHOH + 3O2 reaction, eclipsing alternative outcomes such as amino formic acid (NH2COOH) and formimidic acid (HN = C(H)-OH). At atmospheric conditions pertinent to the troposphere, the branching fraction value for the formation of formamide is about 99%, coupled with a rate constant of 5.5 x 10-12 cm3 molecule-1 s-1. Finally, we have scrutinized the detrimental impact of formamide on the atmosphere. Interaction of formamide with atmospheric hydroxyl radicals could give rise to the production of potentially perilous compounds such as HNCO. Further, unreacted NHCH2OH radicals may initiate the formation of carcinogenic nitrosamines when reacting with trace N-oxides (namely, NO and NO2). This, in turn, escalates the environmental risk factors. [ABSTRACT FROM AUTHOR]

DNA is a complex multi-resolution molecule whose theoretical study is a challenge. Its intrinsic multiscale nature requires chemistry and quantum physics to understand the structure and quantum informatics to explain its operation as a perfect quantum computer. Here, we present theoretical results of DNA that allow a better description of its structure and the operation process in the transmission, coding, and decoding of genetic information. Aromaticity is explained by the oscillatory resonant quantum state of correlated electron and hole pairs due to the quantized molecular vibrational energy acting as an attractive force. The correlated pairs form a supercurrent in the nitrogenous bases in a single band π -molecular orbital (π -MO). The MO wave function (Φ) is assumed to be the linear combination of the n constituent atomic orbitals. The central Hydrogen bond between Adenine (A) and Thymine (T) or Guanine (G) and Cytosine (C) functions like an ideal Josephson Junction. The approach of a Josephson Effect between two superconductors is correctly described, as well as the condensation of the nitrogenous bases to obtain the two entangled quantum states that form the qubit. Combining the quantum state of the composite system with the classical information, RNA polymerase teleports one of the four Bell states. DNA is a perfect quantum computer. [ABSTRACT FROM AUTHOR]

Adsorption and desorption of gases on liquid or solid substrates are involved in multiphase processes and heterogeneous chemical reactions. The desorption energy (Edes0), which depends on the intermolecular forces between adsorbate and substrate, determines the residence time of chemical species at interfaces. We show how Edes0 and temperature influence the net uptake or release of gas species, the rates of surface–bulk exchange and surface or bulk reactions, and the equilibration timescales of gas–particle partitioning. Using literature data, we derive a parameterization to estimate Edes0 for a wide range of chemical species based on the molecular mass, polarizability, and oxygen-to-carbon ratio of the desorbing species independent of substrate-specific properties, which is possible because of the dominant role of the desorbing species' properties. Correlations between Edes0 and the enthalpies of vaporization and solvation are rooted in molecular interactions. The relation between Edes0 and desorption kinetics reflects the key role of interfacial exchange in multiphase processes. For small molecules and semi-volatile organics (VOC, IVOC, SVOC), Edes0 values around 10–100 kJ mol -1 correspond to desorption lifetimes around nanoseconds to days at room temperature. Even higher values up to years are obtained at low temperatures and for low volatile organic compounds (LVOC, ELVOC/ULVOC) relevant for secondary organic aerosols (SOA). Implications are discussed for SOA formation, gas–particle partitioning, organic phase changes, and indoor surface chemistry. We expect these insights to advance the mechanistic and kinetic understanding of multiphase processes in atmospheric and environmental physical chemistry, aerosol science, materials science, and chemical engineering. [ABSTRACT FROM AUTHOR]

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This study focuses on modeling of deep eutectic solvents (DESs) assisted liquid-liquid-extraction of Am(III), U(VI), Eu(III). In the present work, DESs are having tri – n octyl phosphine oxide (TOPO) and choline chloride acetate as hydrogen bond acceptor and malonic acid, oxalic acid and glycolic acid as hydrogen bond donor. The UNIQUAC-extended-PDH* model is used in the extraction formulation incorporating weak long-range interactions and short-range interactions. Metaheuristic algorithm, such as genetic algorithm, is employed for the determination of thermodynamically consistent binary interaction parameters using a pool of 40 tielines across six systems. The estimation of efficiency evaluation and extraction quantification contributes to a deeper understanding of the behavior of deep eutectic solvents in the extraction of lanthanides and actinides. Accurate modeling: UNIQUAC-ext-PDH* model effectively predicts DES extraction properties, aiding process development. Extraction optimization: Variations in extraction efficiency observed among DESs based on different acids, suggesting potential for optimization strategies. DES as co-solvent vs. extractant: Comparison reveals differences in extraction behavior, providing insights for selecting the more favorable option in lanthanide and actinide extraction. [ABSTRACT FROM AUTHOR]

A series of environmentally friendly non-isocyanate polyurethanes (NIPUs) was synthesized through a polycondensation reaction of as-synthesized semi-bio-based bis-cyclic carbonate with diamine derivatives. The synthesis of biscyclic carbonate was realized, for the first time, from 1-thioglycerol and polyethylene glycol diacrylate via thiol-ene click and transcarbonation reaction, respectively. The impacts of using different diamine derivatives on the chemical structural, mechanical properties, thermal stability, and surface wettability of the NIPUs were determined. It was found that the NIPU containing fatty acid-based diamine decomposed at a lower temperature than that of other polymers. Besides, it demonstrated a lower Young’s modulus and a higher tensile strain at break, possibly due to its four-branched structure and greater flexibility. Meanwhile, the NIPU prepared with p-xylylenediamine provided the highest decomposition temperature, owing to an aromatic moiety in the polymer’s backbone, which improved its stiffness and thermal stability. Furthermore, it was understood that the NIPU containing diamino-N-methyldipropyl-amine exhibited a higher Young’s modulus and a lower tensile strain at break, as it had a nitrogen atom in its structure and a trigonal pyramidal configuration with the highest density of hydrogen bonds between polymer chains. Most of the developed NIPUs displayed hydrophobic surface properties, offering promising alternatives to isocyanate-based coating materials. [ABSTRACT FROM AUTHOR]

Storing energy is a major challenge in achieving a 100% renewable energy system. One promising approach is the production of green hydrogen from wind power. This work proposes a method for optimizing the design of wind-hydrogen systems for existing onshore wind farms in order to achieve the lowest possible levelized cost of hydrogen (LCoH). This is done by the application of a novel Python-based optimization model that iteratively determines the optimal electrolyzer position and distribution mode of hydrogen for given wind farm layouts. The model includes the costs of all required infrastructure components. It considers peripheral factors such as existing and new roads, necessary power cables and pipelines, wage and fuel costs for truck transportation, and the distance to the point of demand (POD). Based on the results, a decision can be made whether to distribute the hydrogen to the POD by truck or pipeline. For a 23.4MW onshore wind farm in Germany, a minimal LCoH of EUR 4.58 kgH2-1 at an annual hydrogen production of 241.4 tH2a-1 is computed. These results are significantly affected by the position of the electrolyzer, the distribution mode, varying wind farm and electrolyzer sizes, and the distance to the POD. The influence of the ratio of electrolyzer power to wind farm power is also investigated. The ideal ratio between the rated power of the electrolyzer and the wind farm lies at around 10 %, with a resulting capacity factor of 78% for the given case. The new model can be used by system planners and researchers to improve and accelerate the planning process for wind-hydrogen systems. Additionally, the economic efficiency, hence competitiveness, of wind-hydrogen systems is increased, which contributes to an urgently needed accelerated expansion of electrolyzers. The results of the influencing parameters on the LCoH will help to set development goals and indicate a path towards a cost-competitive green wind-hydrogen system. [ABSTRACT FROM AUTHOR]

New data on the thermal behavior, sublimation, and melting of (hexafluoroacetylacetonato)(cyclooctadiene-1,5)copper, [Cu(cod)(hfac)], have been obtained. The condensed phase was studied by thermal and differential thermal analysis and differential scanning calorimetry. The temperature, enthalpy, and entropy of melting of the complex were determined. The temperature dependence of the saturated vapor pressure of [Cu(cod)(hfac)] in the temperature range 293–337 K was obtained by the Knudsen effusion method with mass spectrometric recording of the gas phase composition. The thermodynamic characteristics of sublimation were calculated at the average temperature over the experimental range and at 298.15 K: (Tav) = 94.8 ± 1.5 kJ mol–1; (Tav) = 200.9 ± 3.2 J mol–1 K–1; (298.15 K) = 95.8 ± 3.1 kJ mol–1; (298.15 K) = 203.5 ± 6.6 J mol–1 K–1. The obtained values are compared with data for a similar iridium(I) compound, [Ir(cod)(hfac)]. The results were used formulate approaches to evaluation of the thermodynamic properties of [M(cod)(hfac)] complexes to determine the optimum conditions for the deposition of metal-containing coatings. These approaches are necessary in those cases when compounds of this type (e.g., [Ag(cod)(hfac)]) are hypersensitive to heating and it is impossible to determine reliable thermodynamic characteristics experimentally. [ABSTRACT FROM AUTHOR]

Mixed-ligand complexes of magnesium with fluorinated β-diketones and diamines are promising as precursors for the preparation of thin MgF2 films by metal-organic chemical vapor deposition (MOCVD). The currently most volatile representative of this family, [Mg(tmeda)(ofhac)2] (tmeda = (CH3)2NCH2CH2CN(CH3)2, ofhac = C2F5COCHCOCF ), was studied. The melting process was characterized by DSC (Tm = 354.4 ± 0.6 K, ∆mH = 23.3 ± 0.9 kJ/mol). The complex was shown to be stable in the condensed phase up to at least 473 K. The temperature dependence of the heat capacity was studied in the range 298–403 K (DSC, using sapphire as a standard). The temperature dependences of the saturated vapor pressure over the solid (318–352 K) and liquid (358–393 K) complex were measured by transport in a helium flow. The thermodynamic parameters of sublimation and vaporization were determined. The possible isomers of the complex (based on the position of the C2F5 substituents) were compared using quantum-chemical calculations (B3LYP-D3(BJ)/def2-SVP, def2-TZVP, and OPBE/TZ2P-J). [ABSTRACT FROM AUTHOR]

Electrification to reduce or eliminate greenhouse gas emissions is essential to mitigate climate change. However, a substantial portion of our manufacturing and transportation infrastructure will be difficult to electrify and/or will continue to use carbon as a key component, including areas in aviation, heavy-duty and marine transportation, and the chemical industry. In this Roadmap, we explore how multidisciplinary approaches will enable us to close the carbon cycle and create a circular economy by defossilizing these difficult-to-electrify areas and those that will continue to need carbon. We discuss two approaches for this: developing carbon alternatives and improving our ability to reuse carbon, enabled by separations. Furthermore, we posit that co-design and use-driven fundamental science are essential to reach aggressive greenhouse gas reduction targets., (© 2024. Argonne National Laboratory, Battelle Memorial Institute, UT- Battelle, LLC, Brookhaven National Laboratory, National Renewable Energy Laboratory, AMES National Laboratory, Lawrence Berkley National Laboratory, SLAC National Accelerator Laboratory, Booz Allen Hamilton, BASF Corporation and The Author(s), under exclusive licence to Springer Nature Limited. This work contains contributions, authored by US Government employees in the course of their official duties, which are not subject to copyright protection in the US. Foreign copyright protection for these contributions may still apply.)