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Redox potentials depend on the nature of the solvent/electrolyte through the solvation energies of the ionic solute species. For concentrated electrolytes, ion solvation may deviate significantly from the Born model predictions due to ion pairing and correlation effects. Recently, Ghorai and Matyushov [J. Phys. Chem. B 124, 3754–3769 (2020)] predicted, on the basis of linear response theory, an anomalous trend in the solvation energies of room temperature ionic liquids, with deviations of hundreds of kJ/mol from the Born model for certain size solutes/ions. In this work, we computationally evaluate ionic solvation energies in the prototypical ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate (BMIM/BF4), to further explore this behavior and benchmark several of the approximations utilized in the solvation energy predictions. For comparison, we additionally compute solvation energies within acetonitrile and molten NaCl salt to illustrate the limiting behavior of purely dipolar and ionic solvents. We find that the overscreening effect, which results from the inherent charge oscillations of the ionic liquid, is substantially reduced in magnitude due to screening from the dipoles of the molecular ions. Therefore, for the molten NaCl salt, for which the ions do not have permanent dipoles, modulation of ionic solvation energies from the overscreening effect is most significant. The conclusion is that ionic liquids do indeed exhibit unique solvation behavior due to peak(s) in the electrical susceptibility caused by the ion shell structure; redox potential shifts for BMIM/BF4 are of more modest order ∼0.1 V, but may be larger for other ionic liquids that approach molten salt behavior. [ABSTRACT FROM AUTHOR]

Taking into account the electron-rich and visible light response of thiophene, first-principles calculations have been carried out to explore the photocatalytic activity of donor–acceptor polymers incorporating thiophene and boron. Honeycomb-kagome boron–thiophene (BTP) polymers with varying numbers of thiophene units and fixed B center atoms are direct bandgap semiconductors with tunable bandgaps ranging from 2.41 to 1.88 eV and show high absorption coefficients under the ultraviolet and visible regions of the solar spectrum. Fine-tuning the band edges of the BTP polymer is efficiently achieved by adjusting the pore size through the manipulation of thiophene units between the B centers. This manipulation, achieved without excessive chemical functionalization, facilitates the generation of an appropriate quantity of photoexcited electrons and/or holes to straddle the redox potential of the water. Our study demonstrates that two units between B centers of thiophene in BTP polymers enable overall photocatalytic water splitting, whereas BTP polymers with larger pores solely promote photocatalytic hydrogen reduction. Moreover, the thermodynamics of hydrogen and oxygen reduction reactions either proceed spontaneously or need small additional external biases. Our findings provide the rationale for designing metal-free and single-material polymer photocatalysts based on thiophene, specifically for achieving efficient overall water splitting. [ABSTRACT FROM AUTHOR]

Electrochemical and photochemical hydrogen (H2) evolution activities of a 6-fluoro-2-hydroxypyridinate (fhp−)-bridged paddlewheel-type dirhodium (Rh2) complex, [Rh2(fhp)4], were investigated through experimental and theoretical approaches. In DMF, the [Rh2(fhp)4] underwent a one-electron reduction (assigned to Rh24+/3+) at −1.31 V vs SCE in the cathodic region. Adding trifluoroacetic acid as a proton source to the electrochemical cell containing [Rh2(fhp)4], the significant catalytic current, i.e., electrochemical H2 evolution, was observed; the turnover frequency and overpotential of electrochemical H2 evolution were 18 244 s−1 and 732 mV, respectively. The reaction mechanism of electrochemical H2 evolution catalyzed by [Rh2(fhp)4] in DMF was examined in detail by theoretically predicting the redox potentials and pKa values of the reaction intermediates using density functional theory calculations. The calculations revealed that (i) the formation of a one-electron reduced species, [Rh2(fhp)4]−, triggered for H2 evolution and (ii) the protonation and reduction processes of [Rh2(fhp)4]− to further reduced hydride intermediates proceeded directly via a concerted proton–electron transfer mechanism. Moreover, [Rh2(fhp)4] was shown to be a highly efficient H2 evolution catalyst (HEC) for photochemical proton reduction reactions when combined with an artificial photosynthetic (AP) system containing [Ir(ppy)2(dtbbpy)]PF6 and triethylamine, which served as a photosensitizer and a sacrificial electron donor, respectively. Under visible light irradiation, the total amount of H2 evolved and its turnover number (per Rh ion) were 1361.0 µmol and 13 610, respectively, which are superior to those of previously reported AP systems with rhodium complexes as HEC. [ABSTRACT FROM AUTHOR]

Superconcentrated aqueous electrolytes have recently emerged as a new class of electrolytes, called water-in-salt electrolytes. They are distinguished, in both weight and volume, by a quantity of salt greater than water. Currently, these electrolytes are attracting major interest, particularly for application in aqueous rechargeable batteries. These electrolytes have only a small amount of free water due to an ultrahigh salt concentration. Consequently, the electrochemical stability window of water is wider than the predicted thermodynamic value of 1.23 V. Hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) have been shown to be shifted to more negative and positive potentials, respectively. The decrease in free water population is recognized as being involved in the increase in the electrochemical stability window of water. Here, we study the quantitative contribution of the decrease in the free water molecule concentration to the permittivity of the solution and of the activity of water to the OER and HER overpotentials when the salt concentration increases. We compare our model with that of Kornyshev and get three types of electrolyte structures: diluted, gradient of water contents, and aggregation. The theoretical calculation of the redox potentials of the OER and HER is compared with the experimentally determined electrochemical properties of aqueous LiTFSI electrolytes. [ABSTRACT FROM AUTHOR]

Riverine environments host diverse microbial communities, exhibiting distinctive assemblies at both microscopic and macroscopic levels. Despite the complexity of microbial life in rivers, the underlying factors that shape the community structure across different compartments remain elusive. Herein, we characterized microbial community composition of biofilm and planktonic (water column) compartments in five naturally saline inland streams and a freshwater stream to examine changes in microbial communities following salinization via sequencing of the microbial 16S rRNA gene. Significant differences in specific conductivity, oxidation–reduction potential, dissolved oxygen, and pH among the sampled streams were measured, as were significant differences in the microbial community composition between the planktonic and biofilm. The bacterial families Bacillaceae, Vicinamibacterceae, and Micrococcaceae were significantly more abundant in the biofilm compartment, while Methylophilaceae, Alcaligenaceae, Spirosomaceae, Burkholderiaceae, and Comamonadaceae were more abundant in the planktonic compartment. In addition, salinity (based on specific conductivity) influenced the microbial community composition in both compartments, with higher sensitivity of the planktonic compartment. Increases in the bacterial families Shewanellaceae, Marinomonadaceae, and Saccharospirillaceae or loss of Anaeromyxobacteraceae could be indicative of increased salinity within inland streams. Our results suggest that monitoring of microbial assemblages of freshwater ecosystems could be used as early warning signs of increased salinization levels. [ABSTRACT FROM AUTHOR]

In pursuing sustainable technologies, organic electronic-based materials have witnessed remarkable progress, with polyfluorene (PF) among the blue light-emitting polymers garnering significant attention. PF, renowned for its remarkable light absorption and exceptional optoelectronic properties, exhibits great potential for various applications including display technologies, solar cells, lasers and transistors. Nonetheless, the diverse phases in PF significantly affect the performance of optoelectronic devices, predominantly due to the coexistence of different conformations in thin films, while promising, PF confronts hurdles related to stability and degradation during operation, leading to spectral changes and colour purity issue. Since the early 1990s, various studies have been devoted by researchers to determine the chemical changes in the PF chain and its functional groups after being subjected to different types of degradation with the aim of controlling and retarding the decomposition process. Another alternative strategy is to promote the formation of β-phase in PF, which is characterised by well-ordered conformation. This review aims to provide a comprehensive overview of PF degradation behaviour, modes and mechanisms. Various approaches to delay and suppress PF degradation are discussed. Meanwhile, the role of the β-phase in suppressing PF degradation and enhancing optoelectronic applications has also been highlighted. Thus, scientists are diligently attempting to enhance the formation and stability of the β-phase to improve the performance of optoelectronic applications. [ABSTRACT FROM AUTHOR]

We have developed a family of dinucleating ligands with varying terminal donors to generate dinuclear peroxo and high-valent complexes and to correlate their stabilities and reactivities with their molecular and electronic structures as a function of the terminal donors. It appears that the electron-donating ability of the terminal donors is an important handle for controlling these stabilities and reactivities. Here, we present the synthesis of a new dinucleating ligand with potentially strong donating terminal imidazole donors. As CoII ions are sensitive to variations in donor strength in terms of coordination number, magnetism, UV-Vis-NIR spectra, redox potentials, we probe the electron donation ability of this new ligand in CoIICoII complexes in comparison to the parent CoIICoII complexes with terminal pyridine donors and we synthesize the analogous CoIICoII complexes with terminal 6-methylpyridines and methoxy-substituted pyridines. The molecular structures show indeed strong variations in coordination numbers and bond lengths. These differences in the molecular structures are reflected in the magnetic properties and in the d–d transitions demonstrating that the molecular structures remain intact upon dissolution. The redox potentials are analyzed with respect to the electron donation ability and are the only handle to observe an effect of the methoxy-substituted pyridines. All data taken together show the following order of electron donating ability for the terminal donors: 6-methylpyridines ≪ pyridines < methoxy-substituted pyridines ≪ imidazoles. [ABSTRACT FROM AUTHOR]

Polymeric micelles (PMs) have demonstrated significant impact as potential cargo carriers, primarily due to their exceptional physicochemical features. One of the major concerns in the field of controlled/targeted drug delivery is with hydrophobic drugs. In this context, PMs have certain advantages, in particular the presence of a hydrophobic core that interacts with the cargo and delivers in the desired site of action. Additionally, because of the stimuli-responsive nature of PMs, they can react to diverse intracellular and extracellular biological cues, such as pH, altered redox potentials, and heightened enzyme activity. Owing to "smart" behavior, the PMs become promising candidates for the targeted delivery of anticancer drugs and are used as imaging agents, thereby serving a range of therapeutic and diagnostic functions. The establishment and validation of robust methodologies for characterizing micelles represent the foundational steps pivotal to their advancement and eventual clinical success. In order to ensure substantial drug encapsulation followed by release, the design of PMs took a pivotal role. It is essential to design and develop the PMs in such a way so that they can interact with the cargo, enhance the payload and release in a sustained/burst manner (depending on the requirement on the desired site). Therefore, the impact of the synthesis processes, the different techniques to characterize the PMs and their potential applications in the field of biomedical science have been discussed in detail. [ABSTRACT FROM AUTHOR]

Bacterial reduction of hexavalent chromium (VI) to chromium (III) is a sustainable bioremediation approach. However, the Cr(VI) containing wastewaters are often characterized with complex conditions such as high salt, alkaline pH and heavy metals which severely impact the growth and Cr(VI) reduction potential of microorganisms. This study investigated Cr(VI) reduction under complex haloalkaline conditions by an Alteromonas sp. ORB2 isolated from aerobic granular sludge cultivated from the seawater-microbiome. Optimum growth of Alteromonas sp. ORB2 was observed under haloalkaline conditions at 3.5–9.5% NaCl and pH 7–11. The bacterial growth in normal culture conditions (3.5% NaCl; pH 7.6) was not inhibited by 100 mg/l Cr(VI)/ As(V)/ Pb(II), 50 mg/l Cu(II) or 5 mg/l Cd(II). Near complete reduction of 100 mg/l Cr(VI) was achieved within 24 h at 3.5–7.5% NaCl and pH 8–11. Cr(VI) reduction by Alteromonas sp. ORB2 was not inhibited by 100 mg/L As(V), 100 mg/L Pb(II), 50 mg/L Cu(II) or 5 mg/L Cd(II). The bacterial cells grew in the medium with 100 mg/l Cr(VI) contained lower esterase activity and higher reactive oxygen species levels indicating toxicity and oxidative stress. In-spite of toxicity, the cells grew and reduced 100 mg/l Cr(VI) completely within 24 h. Cr(VI) removal from the medium was driven by bacterial reduction to Cr(III) which remained in the complex medium. Cr(VI) reduction was strongly linked to aerobic growth of Alteromonas sp. The Cr(VI) reductase activity of cytosolic protein fraction was pronounced by supplementing with NADPH in vitro assays. This study demonstrated a growth-dependent aerobic Cr(VI) reduction by Alteromonas sp. ORB2 under complex haloalkaline conditions akin to wastewaters. [ABSTRACT FROM AUTHOR]

This paper theoretically studies the photocatalytic performance of g-C3N4 self codoped with C–N pair using first-principles. Calculations show that the system with a N2–C1 pair been replaced is the most stable structure. The difference in PDOS after codoping results from the neutral 2p orbital energy difference between the substitution and original atoms, as well as the change in interaction among all atoms after codoping. The band gap can be reduced by 0.41 eV through self C–N codoping. The visible light absorption ability is obviously enhanced through codoping. Both the CBM and VBM of g-C3N4 after codoping are still enough to meet the redox potentials for splitting water. In general, the g-C3N4 self codoped with C and N should have good performance as photocatalyst in water splitting process. [ABSTRACT FROM AUTHOR]

Diagnostic reference levels (DRLs) and achievable doses (ADs) provide guidance to optimise radiation doses for patients undergoing medical imaging procedures. This multi-centre study aimed to compare institutional DRLs (IDRLs) across hospitals, propose ADs and multi-centric DRLs (MCDRLs) for four common x-ray examinations in Sri Lanka, and assess the potential for dose reduction. A prospective cross-sectional study of 894 adult patients referred for abdomen anteroposterior (AP), kidney-ureter-bladder (KUB) AP, lumbar spine AP, and lumbar spine lateral (LAT) x-ray examinations was conducted. Patient demographic information (age, sex, weight, BMI) and exposure parameters (tube voltage, tube current-exposure time product) were collected. Patient dose indicators were measured in terms of kerma-area product (PKA) using a PKA meter. IDRLs, ADs, and MCDRLs were calculated following the International Commission on Radiological Protection guidelines, with ADs and MCDRLs defined as the 50th and 75th percentiles of the median PKA distributions, respectively. IDRL ranges varied considerably across hospitals: 1.42–2.42 Gy cm2 for abdomen AP, 1.51–2.86 Gy cm2 for KUB AP, 0.83–1.65 Gy cm2 for lumbar spine AP, and 1.76–4.10 Gy cm2 for lumbar spine LAT. The proposed ADs were 1.82 Gy cm2 (abdomen AP), 2.03 Gy cm2 (KUB AP), 1.27 Gy cm2 (lumbar spine AP), and 2.21 Gy cm2 (lumbar spine LAT). MCDRLs were 2.24 Gy cm2 (abdomen AP), 2.40 Gy cm2 (KUB AP), 1.43 Gy cm2 (lumbar spine AP), and 2.38 Gy cm2 (lumbar spine LAT). Substantial intra- and inter-hospital variations in PKA were observed for all four examinations. Although ADs and MCDRLs in Sri Lanka were comparable to those in the existing literature, the identified intra- and inter-hospital variations underscore the need for dose reduction without compromising diagnostic information. Hospitals with high IDRLs are recommended to review and optimise their practices. These MCDRLs serve as preliminary national DRLs, guiding dose optimisation efforts by medical professionals and policymakers. [ABSTRACT FROM AUTHOR]

The paper is devoted to the measurements of one‐electron redox potentials of transient free radicals Eo. These values can be measured in the reversible redox reactions of radicals under investigation with a reference pair, which Eo is known. Several Eo of transient radicals are presented. The convenient and important objects for Eo measurement are quinone/semiquinone radical‐anions. A general problem of measurement of thermodynamic properties of short‐lived transients is discussed. [ABSTRACT FROM AUTHOR]

China, as a significant global consumer of chemical fertilizers and a leading producer of rice, faces challenges associated with low fertilizer efficiency and fewer utilization options of rice husks. The development of rice husk biochar‐based fertilizers (RHBF) offers a strategic solution to address these issues. In this study, diverse biochar fertilizer production techniques were used to develop four types of fertilizers: blended RHBF, soaked RHBF, high‐pressure soaked RHBF, and pure rice husk biochar coated fertilizer. The nutrients slow‐releasing performance of these four RHBF were compared by hydrostatic and soil column intermittent leaching methods. Effects of their application on rice growth, yield, and cadmium reduction potential were analyzed and compared by the pot trial. Results demonstrated that nutrients of the four RHBF were generally released slower in the soil compared with the conventional compound fertilizer (CK). The slow nutrient release effect was more pronounced under high‐pressure soaked RHBF. Notably, in the soil column leaching experiment, the cumulative leaching rates of nitrogen and K2O for RHBF3 (12.0% and 13.9%) were greatly lower than those of CK (42.3% and 51.3%). Moreover, the application of RHBF induced a marked enhancement in the nutrient use efficiency, grain yield, harvest index, and photosynthetic characteristics compared to CK. The average agronomic efficiency of P2O5 for the four RHBF increased by 102.8% compared with CK, while the average grain yield of the four RHBF increased by 20.6%. In addition, RHBF showed a significant reduction in Cd mobilization by an average of 80.1% compared to CK. This study offers a promising model for enhancing the comprehensive performance of RHBF and optimizing traditional fertilizer application practices. [ABSTRACT FROM AUTHOR]

In the present study, we have investigated factors affecting the accuracy of computational chemistry calculation of redox potentials, namely the gas‐phase ionization energy (IE) and electron affinity (EA), and the continuum solvation effect. In general, double‐hybrid density functional theory methods yield IEs and EAs that are on average within ~0.1 eV of our high‐level W3X‐L benchmark, with the best performing method being DSD‐BLYP/ma‐def2‐QZVPP. For lower‐cost methods, the average errors are ~0.2–0.3 eV, with ωB97X‐3c being the most accurate (~0.15 eV). For the solvation component, essentially all methods have an average error of ~0.3 eV, which shows the limitation of the continuum solvation model. Curiously, the directly calculated redox potentials show errors of ~0.3 eV for all methods. These errors are notably smaller than what can be expected from error propagation with the two components (IE and EA, and solvation effect). Such a discrepancy can be attributed to the cancellation of errors, with the lowest‐cost GFN2‐xTB method benefiting the most, and the most accurate ωB97X‐3c method benefiting the least. For organometallic species, the redox potentials show large deviations exceeding ~0.5 eV even for DSD‐BLYP. The large errors are attributed to those for the gas‐phase IEs and EAs, which represents a major barrier to the accurate calculation of redox potentials for such systems. [ABSTRACT FROM AUTHOR]

Benzo[d]‐X‐zolyl‐pyridinyl (XO, S, NH) radicals represent a promising class of redox‐active molecules for organic batteries. We present a multistep screening procedure to identify the most promising radical candidates. Experimental investigations and highly correlated wave function‐based calculations are performed to determine benchmark redox potentials. Based on these, the accuracies of different methods (semi‐empirical, density functional theory, wave function‐based), solvent models, dispersion corrections, and basis sets are evaluated. The developed screening procedure consists of three steps: First, a conformer search is performed with CREST. The molecules are selected based on the redox potentials calculated using GFN2‐xTB. Second, HOMO energies calculated with reparametrized B3LYP‐D3(BJ) and the def2‐SVP basis set are used as selection criteria. The final molecules are selected based on the redox potentials calculated from Gibbs energies using BP86‐D3(BJ)/def2‐TZVP. With this multistep screening approach, promising molecules can be suggested for synthesis, and structure–property relationships can be derived. [ABSTRACT FROM AUTHOR]

Open shell species are alluring significant attention owing to their unique physiochemical properties in redox chemistry for activating remarkably stable bonds. Solvated electrons are one of them that have been extensively investigated due to their high reduction potential (Ered=−2.9 V vs SHE in CH3CN), diverse substrate activation, and promising applications. If the activating species have a larger redox potential with a longer lifetime, then the broader range of substrates will be activated. Hence, the solvated electron qualifies as a super‐reductant with these qualities. However, due to safety issues, generating solvated electrons by dissolving alkali metals in an ammoniated solvent limits its use towards complicated organic transformations. Instead photochemically generated solvated electron overcome this limitation and is identified as a user‐friendly, sustainable, and much safer alternative approach for producing solvated electrons. In this minireview, we have comprehensively highlighted the recent key methods to generate the solvated electron photochemically, characterization techniques, and its application in organic transformations with selected examples. The minireview provides new opportunities for chemists to understand the conceptual, physical, and mechanistic chemistry principle of this super reductant for exploiting a new photochemical route for the transformations that are difficult to achieve by other means. [ABSTRACT FROM AUTHOR]

Lithium metal batteries (LMBs) have the potential to be the next‐generation rechargeable batteries due to the high theoretical specific capacity and the lowest redox potential of lithium metal. However, the practical application of LMBs is hindered by challenges such as the uncontrolled growth of lithium dendrites, unstable solid electrolyte interphase (SEI), and excessive volume change of Li metal. To solve these issues, the design of high‐performance lithium metal anodes (LMAs) with various 3D structures is critical. Targeting at realizing the "bottom–up" Li deposition to fully utilize the 3D architecture, in recent years, strategies such as gradient host materials construction, magnetic field modulation, SEI component design, and so on have attracted intensive attention. This review begins with a fundamental discussion of the Li nucleation and deposition mechanism. The recent advances in the aspects of construction strategies and modification methods that enable the "bottom–up" Li deposition within advanced 3D host materials, with a particular emphasize on their design principles are comprehensively overviewed. Finally, future challenges and perspectives on the design of advanced hosts toward practical LMAs are proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electron storage in defective R 2 and effective release to H 2 O 2 to generate ROS-enabled night catalysis. • Broad spectrum response and better carrier separation improved the photoactivities. • TC degradation pathways are proposed in light of DFT calculations and LC-MS data. Tetracycline (TC) antibiotics and dyes are the prevalent water contaminants, and their removal from the water through photocatalysis is a plausible approach. However, most semiconductors in their pristine form need to be improved to be exploited in photocatalysis owing to poor photoresponse, intense carrier recombination, and inertness without irradiation. Herein, we demonstrate the modification of defective WO 3-x by rGO and AgBiS 2 in the form of WO 3-x /rGO/AgBiS 2 (R 2). It exploits the superior conductivity and synergism of rGO to inhibit carrier recombination; thereby, Z-scheme heterojunction with AgBiS 2 provides high redox potential. Defects in WO 3-x enable electron (e-) storage in R 2 , which decomposes H 2 O 2 to generate ROS without irradiation. Owing to these essences and broad-spectrum response, it removed 93.72, 82.77, and 84.82% of TC during photo-Fenton (PFR), night-Fenton (NFR), and photocatalytic (PCR) reactions, respectively. Its removal rates reached 94.74, 81.54, and 87.50% against rhodamine B (RhB) during PFR, NFR, and PCR, respectively. It is superior to memory catalysis (MC) and conventional Fenton reactions (CFR) because it can perform without and with irradiation across a broader pH range. So, this work is conducive to designing WO 3-x -based catalysts to combat environmental and energy crises. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: As a versatile earth‐abundant transition metal, Cu has long been widely applied in the C—C and C—X bond forming reactions. As for now, low‐valent Cu(I) is known to reduce the redox active electrophiles via an SET pathway to give the corresponding radical and Cu(II) species. The resulting Cu(II) species can interact with the radical via the out‐sphere pathway, affording the coupling product. Alternatively, Cu(II) can trap the radical through the inner‐sphere process to generate Cu(III) species and then realize challenging bond formations due to the facile reductive elimination of Cu(III) intermediate. Although copper catalysis has been widely applied in arylations of various nucleophiles, copper‐catalyzed enantioconvergent nucleophilic substitutions of racemic alkyl electrophiles have been less explored, likely due to the difficulties in overcoming the reduction potential of alkyl electrophiles, elimination of side reactions, and enantiomeric control. In order to overcome the high reduction potential of alkyl electrophiles, the photo‐induced strategy has been developed under mild conditions. An alternative strategy with new anionic tridentate ligands has also been reported in this regard. This review summarizes recent developments in copper‐catalyzed enantioconvergent nucleophilic substitutions of alkyl electrophiles by various nucleophiles to realize C—N, C—C, C—B, C—P and C—O bond formations and their brief mechanistic studies. Key Scientists: In 2016, Fu and Peters et al. reported the first photo‐induced Cu‐catalyzed enantiocovergent C—N bond formations of tertiary alkyl halides with N‐hetereocycles, opening the door for the Cu‐catalyzed enantiocovergent nucleophilic substitutions. The photo‐induced strategy has been developed that greatly enhances the reducing power of Cu(I). The Cu‐catalyzed enantioconvergent cyanation (decarboxylative) and borylation were then successively presented by Liu and Ito in 2017 and 2018, respectively. Other than the photo‐induced strategy, Liu et al. in 2019 demonstrated that anionic ligands can also significantly enhance the reducing ability of Cu(I). The cinchona‐based chiral anionic tridentate ligands have been utilized for a series of Cu‐catalyzed enantiocovergent nucleophilic substitutions. Zhang et al. also developed chiral anionic tridentate ligands containing the oxazoline binding sites in 2020. In 2020, Xiao and Lu et al. reported the Cu‐catalyzed enantiocovergent deoxygenative cyanation. Later in 2022, Feng and Liu et al. developed the new guanidine hybrid ligands. This review focuses on the Cu‐catalyzed enantioconvergent nucleophilic substitutions that emerged in recent years. [ABSTRACT FROM AUTHOR]

The study evaluated the effect of adding dandelion extract on the characteristics of raw-ripening pork sausages while reducing the nitrite addition from 150 to 80 mg/kg. The sausages were made primarily from pork ham (80%) and pork jowl (20%). The process involved curing, preparing the meat stuffing, forming the links, and then subjecting the sausages to a 21-day ripening period. Physicochemical parameters such as pH, water activity, and oxidation-reduction potential were compared at the beginning of production and after the ripening process. The study also examined the impact of ripening on protein metabolism in pork sausages and compared the protein profiles of different sausage variants. The obtained research results indicate that dandelion-leaf extract (Taraxacum officinale) were rich in phenolic acids, flavonoids, coumarins, and their derivatives (LC-QTOF-MS method). Antiradical activity test against the ABTS+* and DPPH radical, and the TBARS index, demonstrated that addition of dandelion (0.5–1%) significantly improved the oxidative stability of raw-ripening sausages with nitrite content reduction to 80 mg/kg. A microbiological evaluation of the sausages was also carried out to assess the correctness of the ripening process. The total number of viable bacteria, lactic acid bacteria, and coliforms were evaluated and subsequently identified by mass spectrometry. [ABSTRACT FROM AUTHOR]

The E1/2 potential associated with reduction of the linearly-functionalized 6,6′-biazulenic scaffold is accurately correlated to the combined σp Hammett parameters of the substituents over >600 mV range. X-ray crystallographic analysis of the 2,2′-dichloro-substituted derivative revealed unexpectedly short C–Cl bond distances, along with other metric changes, suggesting a non-trivial cycloheptafulvalene-like structural contribution. [ABSTRACT FROM AUTHOR]

This study focuses on the effect of an emerging source of waste, lithium iron phosphate (LFP) cathode materials, on the hydrometallurgical recycling of the currently dominant industrial battery waste that is rich in transition metals (Ni, Co, Mn, and Li). The effects of the dosage of LFP, initial acidity, and timing of LFP reductant addition were investigated in sulfuric acid (H2SO4) leaching (t = 3 h, T = 60 °C, ω = 300 rpm). The results showed that addition of LFP increased both transition metal extraction and acid consumption. Further, the redox potential was lowered due to the increased presence of Fe2+. An initial acidity of 2.0 mol/L H2SO4 with acid consumption of 1.3 kg H2SO4/kg black mass provided optimal conditions for achieving a high leaching yield (Co = 100%, Ni = 87.6%, Mn = 91.1%, Li = 100%) and creating process solutions (Co 8.8 g/L, Ni 13.8 g/L, Li 6.7 g/L, Mn 7.6 g/L, P 12.1 g/L) favorable for subsequent hydrometallurgical processing. Additionally, the overall efficiency of H2O2 decreased due to its decomposition by high concentrations of Fe2+ and Mn2+ when H2O2 was added after t = 2 h, leading to only a minor increase in final battery metals extraction levels. [ABSTRACT FROM AUTHOR]

Atom transfer radical addition (ATRA) of halogenated compounds with alkenes is well established but primary alkyl chlorides are understudied because of the difficult C−Cl bond activation. In this paper, we show that TONs of 61 can be achieved in the ATRA of ethyl chloroacetate onto styrene with [Cp*Ru(Cl)2(PPh3)] and 1,1′‐azobis(cyclohexanecarbonitrile) (ACHN) as a radical initiator, representing a three‐fold improvement compared to previous reports. New catalyst precursors of the type [Cp*Ru(Cl)2(PR3)] were synthesized and tested (R=Me, Et, Cy, Ph, p‐CF3C6H4 and p‐MeOC6H4). The kinetic reaction profiles were studied using in situ ATR−FTIR spectroscopy. Among these complexes, [Cp*Ru(Cl)2(PPh3)] gave the best yields while [Cp*Ru(Cl)2(PMe3)] showed the highest rate. While rates correlate with redox potentials (electronics), our investigation reveals that substrate sterics are important for the overall yield. Density functional theory calculations suggest an open‐shell singlet pathway, where polymerization is kinetically disfavored, explaining the selectivity towards ATRA products. [ABSTRACT FROM AUTHOR]

The synthesis and extensive characterization of nine aryl sulfur diimides (SDIs, Ar−NSN−Ar) are presented with a robust computational and experimental investigation of the fundamental properties of these important members of the thiazyl family of compounds, with particular attention paid to their highly tunable electrochemical behaviour. This is the first work to undertake a systematic comparison of the electrochemical profiles of a coherent series of SDIs to demonstrate and quantify the response of their reduction potentials to substituent electron‐donating and ‐withdrawing properties. This effect is found to be not only exceptionally strong, but also correlates very closely with computed orbital energies. Electron paramagnetic resonance spectroscopy is used to determine the nature, localization, and qualitative lifetimes of the radical anions of SDIs. This work also addresses significant misconceptions about physical properties of SDIs. Experimental data and modern computational methods are employed to provide a resolute answer to the long‐standing contention of the solution‐state conformations of SDIs, and to correct historical mistakes in the assignment of infrared spectroscopic data. High‐quality crystal structures of all SDIs in this work showcase the utility of the recently introduced structural refinement software NoSpherA2, enabling full anisotropic refinement of H‐atoms with accurate C−H bond lengths. [ABSTRACT FROM AUTHOR]

OBJECTIVE To compare the quality of recovery in horses emerging from general anesthesia with or without the assistance of a novel device (recovery-enhancing device [RED]) designed to minimize high-energy falls. ANIMALS 20 mixed-breed horses, between July 1, 2023, and January 24, 2024. METHODS A computer-controlled belay system designed to slow the acceleration of a horse during a fall was evaluated in this study. Horses were randomly assigned to 1 of 2 treatment groups: RED (belay, assisted) or FREE (unassisted). An inertia-measuring unit was fitted to all horses and data were live streamed and recorded onto a computer for further analysis. Recoveries were scored using the composite grading scale (CGS; 0 to 100) by 3 independent observers. Two additional unitless recovery scores (RS and RS’), based on accelerometry values (high accelerations, less desirable), were calculated for each recovery. All the recovery scores were compared between the 2 treatment groups. RESULTS Composite grading scale scores were 26 ± 10 and 46 ± 13 in the RED and FREE groups, respectively (P = .001). The RS was 120 ± 79 and 198 ± 34 for the RED and FREE treatment groups, respectively (P = .015). The RS’ was 32 (7 to 50) and 46 (28 to 44) for the RED and FREE treatment groups, respectively (P = .038). CLINICAL RELEVANCE The RED improves the recovery scores compared with unassisted recoveries. This device may lead to a potential reduction in the number and severity of injuries in horses and personnel involved during the recovery period. [ABSTRACT FROM AUTHOR]

The H2 and CO2-utilizing chemolithoautotrophic microorganisms from the deep subsurface ecosystems have gained considerable importance for their significant role in biogeochemical cycling of carbon. In this study, ten basalt and granite rocks from the deep subsurface environment of the Deccan Traps, India, have been used to enrich chemolithotrophic microorganisms. Following incubation with H2 and CO2 for 90 days at 50˚C, the enrichments showed microbial growth as evident from protein (27–157 mg/L) and carbohydrate (0.1–2.9 mg/L) contents of the enrichment cultures along with a change in pH, dissolved oxygen, and oxidation-reduction potential values. 16 S rRNA gene amplicon sequencing of the metagenomes derived from the enrichment cultures showed selective enrichment of microbial communities compared to the native rock communities. The most abundant bacterial phyla within the native rock samples were Proteobacteria, Actinobacteria, and Firmicutes, whereas the enrichment cultures showed enrichment of Proteobacteria (members of Gamma-Alpha-subdivisions), Actinobacteria, Firmicutes, and others under the chemolithoautotrophic condition. Predictive metabolic profiling using PICRUSt of enriched communities revealed the presence of genes related to H2 oxidation (hyaCD) and CO2 fixation (PGK, ccl, fhs, accABC) as well as genes for value-added product formation (ACSS, LDH, adh, acmAB, adh1, adcBDH, phaC, phbCZB, etc.). A total of 14 bacteria were isolated and identified as Mesorhizobium sp., Ralstonia spp., Massilia spp., Acidovorax spp., and Sphingobium sp. Among the bacterial isolates, Ralstonia sp., and Massilia sp. obtained from basaltic rock showed higher CO2 (up to 8 mg/L) utilization ability, and most of them can produce acetate (up to 14 mg/L). PCR analysis of the functional gene (NiFe-hyd) revealed the presence of probable H2 oxidation pathway in the isolates for their energy metabolism. The study showed the potential of H2 and CO2 utilizing deep subsurface bacterial populations in CO2 capture and value-added product formation. [ABSTRACT FROM AUTHOR]

Background: In response to the opioid crisis in the United States, population-level prescribing of opioids has been decreasing; there are concerns, however, that dose reductions are related to potential adverse events. Objective: Examine associations between opioid dose reductions and risk of 1-month potential adverse events (emergency department (ED) visits, opioid overdose, benzodiazepine prescription fill, all-cause mortality). Design: This observational cohort study used electronic health record and claims data from eight United States health systems in a prescription opioid registry (Clinical Trials Network-0084). All opioid fills (excluding buprenorphine) between 1/1/2012 and 12/31/2018 were used to identify baseline periods with mean morphine milligram equivalents daily dose of ≥ 50 during six consecutive months. Patients: We identified 60,040 non-cancer patients with ≥ one 2-month dose reduction period (600,234 unique dose reduction periods). Main Measures: Analyses examined associations between dose reduction levels (1– < 15%, 15– < 30%, 30– < 100%, 100% over 2 months) and potential adverse events in the month following a dose reduction using logistic regression analysis, adjusting for patient characteristics. Key Results: Overall, dose reduction periods involved mean reductions of 18.7%. Compared to reductions of 1– < 15%, dose reductions of 30– < 100% were associated with higher odds of ED visits (OR 1.14, 95% CI 1.10, 1.17), opioid overdose (OR 1.41, 95% CI 1.09–1.81), and all-cause mortality (OR 1.39, 95% CI 1.16–1.67), but lower odds of a benzodiazepine fill (OR 0.83, 95% CI 0.81–0.85). Dose reductions of 15– < 30%, compared to 1– < 15%, were associated with higher odds of ED visits (OR 1.08, 95% CI 1.05–1.11) and lower odds of a benzodiazepine fill (OR 0.93, 95% CI 0.92–0.95), but were not associated with opioid overdose and all-cause mortality. Conclusions: Larger reductions for patients on opioid therapy may raise risk of potential adverse events in the month after reduction and should be carefully monitored. [ABSTRACT FROM AUTHOR]

This note describes the development and testing of a novel, programmable reversing flow 1D (R1D) experimental column apparatus designed to investigate reaction, sorption, and transport of solutes in aquifers within dynamic reversing flow zones where waters with different chemistries mix. The motivation for constructing this apparatus was to understand the roles of mixing and reaction on arsenic discharging through a tidally fluctuating riverbank. The apparatus can simulate complex transient flux schedules similar to natural flow regimes The apparatus uses an Arduino microcontroller to control flux magnitude through two peristaltic pumps. Solenoid valves control flow direction from two separate reservoirs. In‐line probes continually measure effluent electrical conductance, pH, oxidation–reduction potential, and temperature. To understand how sensitive physical solute transport is to deviations from the real hydrograph of the tidally fluctuating river, two experiments were performed using: (1) a simpler constant magnitude, reversing flux direction schedule (RCF); and (2) a more environmentally relevant variable magnitude, reversing flux direction schedule (RVF). Wherein, flux magnitude was ramped up and down according to a sine wave. Modeled breakthrough curves of chloride yielded nearly identical dispersivities under both flow regimes. For the RVF experiment, Peclet numbers captured the transition between diffusion and dispersion dominated transport in the intertidal interval. Therefore, the apparatus accurately simulated conservative, environmentally relevant mixing under transient, variable flux flow regimes. Accurately generating variable flux reversing flow regimes is important to simulate the interaction between flow velocity and chemical reactions where Brownian diffusion of solutes to solid‐phase reaction sites is kinetically limited. Article impact statement: We developed a low‐cost programmable column experiment apparatus capable of automating reversing flows a range of flux magnitudes. [ABSTRACT FROM AUTHOR]

With a significant share of renewable power generation integrated into the power supply, it is crucial to timely adjust the regulating peak load for coal-fired power plants equipped with CO2 capture to ensure the stable operation of the multi-energy supply system. In this paper, the effects of varying boiler loads on the techno-economic performance of the retrofitted power plant were studied. Furthermore, the potential for reducing the cost of CO2 capture was investigated, and early opportunities for demonstration were discussed. Results showed that when the boiler load decreased from 100% turbine heat acceptance condition to 50% turbine heat acceptance condition, the cost of CO2 capture increased from 37.0 $/t CO2 to 57.0 $/t CO2, cost contribution of energy penalty and extra capital investment also increased from 20.6 $/t-CO2 to 25.7 $/t-CO2, and from 16.4 $/t-CO2 to 31.3 $/t-CO2, respectively. Furthermore, by improving separation efficiency from 0.15 to 0.5, a 25% to 30% reduction in CO2 capture cost can be achieved. The cost of CO2 capture could decrease by 42.2–50.5% when the cumulative capacity reaches 250 GW under the high investment learning rate scenario. According to the distribution of coal prices and renewable energy sources in China, the early demonstration projects of multi-energy supply systems should prioritize the northern region. The results of this work can provide informative references for making roadmaps and policies for CO2 emission reduction toward carbon neutrality. [ABSTRACT FROM AUTHOR]

Redox organization governs an underlying simplicity in living systems. Critically, redox reactions enable the essential characteristics of life: extraction of energy from the environment, use of energy to support metabolic and structural organization, use of dynamic redox responses to defend against environmental threats, and use of redox mechanisms to direct differentiation of cells and organ systems essential for reproduction. These processes are sustained through a redox context in which electron donor/acceptor couples are poised at substantially different steady-state redox potentials, some with relatively reducing steady states and others with relatively oxidizing steady states. Redox-sensitive thiols of the redox proteome, as well as low molecular weight redox-active molecules, are maintained individually by the kinetics of oxidation-reduction within this redox system. Recent research has revealed opposing network interactions of the metallome, redox proteome, metabolome and transcriptome, which appear to be an evolved redox response structure to maintain stability of an organism in the presence of variable oxidative environments. Considerable opportunity exists to improve human health through detailed understanding of these redox networks so that targeted interventions can be developed to support new avenues for redox medicine. [Display omitted] • Opposing redox network interactions maintain stability in variable oxidative environments. • Network interactions exist for the metallome, proteome, transcriptome and metabolome. • Direct molecular antagonism can be discriminated from opposing network structures. • Diurnal redox oscillations could reflect opposing networks in redox stability. • Understanding of redox networks could support new avenues for redox medicine. [ABSTRACT FROM AUTHOR]

Like other Fenton systems, the PDS-based Fenton system still faces the bottleneck of the rapid conversion of Fe(II) to Fe(III) in the system. Our previous researches have found that Fullerol could promote the Fe(III)/Fe(II) cycle in two ways: 1. Fullerol directly reduces Fe(III) into Fe(II); 2. Fullerol complexed with Fe(III) to generate Fullerol-Fe(III) complex with lower redox potential, thereby promoting the formation of Fe(II). This is undoubtedly a good way to solve the bottleneck of the PDS-based Fenton systems, while in recent years, new ideas have been put forward about the type of reactive oxidizing species (ROS) in the PDS-based Fenton systems: ferryl ion species (Fe(IV)) was formed, and played a role of pollutants degradation. In this study, we proved the formation of Fe(IV) during C60 Fullerol–enhanced Fenton-like activation of PDS with visible light irradiation. The experimental results showed that Fe(IV), SO4·− and OH were analyzed in the Fe(III)/PDS/Fullerol system by probes and EPR experiments. The yield of methyl phenyl sulfone (η(PMSO2)) and the results of p-CBA experiment indicated that both Fe(IV) and ·OH played an important role in the Fe(III)/PDS/Fullerol system. Combined with Fe(II) formation and PDS consumption results, it is indicated that with the addition of Fullerol, the Fe(II)/PDS molar ratio increased, and changed major oxidizing intermediate from ·OH to Fe(IV). Under visible light condition, the oxidation rates of BPS in the Fe(III)/PDS/Fullerol system were about 1.55 × 10–2 min−1, which was about five times that of the Fe(III)/PDS system at pH 3.0 (3.10 × 10–3 min−1). This study found that in the Fe(III)/PDS/Fullerol system, both Fe(IV) and ·OH play a role in the degradation of BPS. [ABSTRACT FROM AUTHOR]

Cement–bentonite–soil cut-off walls installed using the trench remixing and deep (TRD) wall method have been widely used to control seepage. The TRD construction is usually executed in two-phase cut-off walls; however, previous studies mainly focus on the properties of the one-phase cut-off walls. Besides, chemical interactions between bentonite and cement will induce a reduction in the swelling potential and water retention capacity of bentonite, leading to a weakness in its seepage barrier performance. Thus, it is of great significance to develop alternative cementitious materials to replace cement for the construction of cement–bentonite–soil cut-off walls. Ground granulated blastfurnace slag (GGBS) has been increasingly used for partial or full replacement of cement in geotechnical engineering. In this study, the performance of cut-off walls constructed using the two-phase TRD method was fully evaluated based on the use of GGBS with the activators of magnesia (MgO) and quicklime (CaO) to replace cement. A series of laboratory tests were first conducted to evaluate the workability (i.e., flowability and bleeding) of fresh bentonite–sand mixtures with four types of binder slurry (i.e., cement, GGBS, MgO-GGBS, and CaO-GGBS). Subsequently, binder–bentonite–sand mixtures that achieved the required workability were selected for unconfined compressive strength (UCS) and permeability tests. The results indicated that both the flowability and the bleeding water of fresh mixtures were remarkably increased by the addition of cement or CaO-GGBS compared to that of GGBS or MgO-GGBS, easily exceeding the acceptable range. It may be attributed to the cation exchange of Ca2+ released from cement or CaO hydration with Na+ in bentonite; however, this interaction might be concealed for the one-phase cut-off walls. More importantly, MgO-GGBS showed much better performance in the strength and permeability than cement; for example, the average 28-day UCS could reach up to 1.12 MPa for the binder type of MgO/GGBS = 1:9 at the binder content of 10% and bentonite content of 3%, four times that of cement. On the other hand, it is revealed that the addition of a large amount of bentonite does not always make a significant improvement on the permeability of two-phase cut-off walls. Overall, the results promote the application of MgO-GGBS as a potential substitute for cement in cut-off walls using the two-phase TRD method. [ABSTRACT FROM AUTHOR]

Plant‐based nanoparticles can be tuned through the frequency of light for efficient synthesis, structural properties, and antibacterial applications. This research assessed the effect of material type (callus and whole‐plant extract) and the interaction with a specific range of light wavelength on AgNP synthesis. All types of AgNPs were characterized by their size, shape, associated functional groups, and surface charge. Interestingly, the size of red light and callus‐based AgNPs (RC‐AgNPs) was smaller (6.32 nm) compared to 14.59 nm for Ultraviolet light and callus‐based AgNPs (UV‐C‐AgNPs). Zeta potential analysis showed that RC‐AgNPs had higher stability (−29.2 mV) compared to UV‐C‐AgNPs (−16.7 mV). Similarly, red light‐based AgNPs had higher Oxidation reduction potential in both whole‐plant‐based and callus‐based AgNPs, indicating a more oxidizing nature compared to those synthesized under UV light. This was confirmed by the lower total phenolic and flavonoid content associated with them and their lower antioxidant activity. The higher antibacterial activities and lower minimum inhibitory concentrations of red light‐based AgNPs against highly resistant pathogenic bacteria demonstrated the role of red light in enhancing antibacterial activity. These results indicate that AgNPs synthesized in red light and callus extract are more active compared to those synthesized under other wavelengths and/or in whole‐plant extracts. [ABSTRACT FROM AUTHOR]

This research developed and evaluated the corrosion-inhibiting efficiency of a natural inhibitor prepared from a bamboo tree [referred to as bamboo leaf extract (BLE)]. The corrosion behavior of steel in BLE-admixed cementitious systems was examined using dynamic-polarization tests and salt-fog tests. The effect of the addition of BLE on the workability and compressive strength of cementitious systems was studied using flow-table and compression tests on mortars. Increased concentration of BLE and the preimmersion period of steel in BLE-admixed pore solution resulted in the increase of corrosion potentials and the reduction of corrosion currents. Furthermore, the addition of BLE improved the workability and compressive strength of mortars, and the mass loss of steel in BLE-admixed mortar was observed to be less than that in the control (BLE-free) specimens. The inhibitor's adsorption on the steel followed the Langmuir isotherm model, suggesting the formation of a protective layer at the steel–electrolyte interface, and accordingly, a 99% reduction of the corrosion current was achieved by preimmersing the steel in simulated concrete pore solution containing 700 ppm BLE for 7 days. [ABSTRACT FROM AUTHOR]

This study investigates the bioactivity profile of wood-rotting fungal species Daedaleopsis confragosa (Bolton) J. Schröt. 1888, focusing on its antioxidant, cytotoxic, and genotoxic activities and enzyme modulation properties with respect to its possible application in terms of enhancing women's reproductive health. Two types of extracts, including those based on EtOH extraction (DC) and hydrodistillation (DCHD), were investigated. The results indicate that the radical scavenging capacity against the DPPH radical and reduction potential were stronger in the DC extracts owing to the higher total phenolic content (TPC) and total flavonoid content (TFC) (25.30 ± 1.05 mg GAE/g d.w. and 2.84 ± 0.85 mg QE/g d.w., respectively). The same trend was observed in the protein phosphatase-1 (PP1) activity and in the genotoxic activity against the δ virus since only the DC extract exhibited DNA disintegration regarding a dilution of 1:100. Conversely, the DCHD extract exhibited increased hemolytic and cytotoxic effects (339.39% and IC50 = 27.76 ± 0.89 μg/mL—72 h incubation, respectively), along with greater inhibition of the AChE enzyme (IC50 = 3.11 ± 0.45 mg/mL) and hemolytic activity. These results suggest that terpenoids and steroids may be responsible for the observed activity in DCHD as these compounds could potentially be extracted following the HD procedure. This comprehensive bioactivity profiling offers valuable insights into the potential therapeutic applications of D. confragosa from Serbia and underscores the importance of further investigations for harnessing its pharmacological potential. [ABSTRACT FROM AUTHOR]

We demonstrate that applying electric field pulses to hepatocytes, in vitro, in the presence of enhanced green fluorescent protein (EGFP)-expressing adeno-associated virus (AAV8) vectors reduces the viral dosage required for a given transduction level by more than 50-fold, compared to hepatocytes exposed to AAV8-EGFP vectors without electric field pulse exposure. We conducted 48 experimental observations across 8 exposure conditions in standard well plates. The electric pulse exposures involved single 80-ms pulses with 375 V/cm field intensity. Our study suggests that electric pulse exposure results in enhanced EGFP expression in cells, indicative of increased transduction efficiency. The enhanced transduction observed in our study, if translated successfully to an in vivo setting, would be a promising indication of potential reduction in the required dose of AAV vectors. Understanding the effects of electric field pulses on AAV transduction in vitro is an important preliminary step. [ABSTRACT FROM AUTHOR]

Biological N2 reduction occurs at sulfur‐rich multiiron sites, and an interesting potential pathway is concerted double reduction/ protonation of bridging N2 through PCET. Here, we test the feasibility of using synthetic sulfur‐supported diiron complexes to mimic this pathway. Oxidative proton transfer from μ‐η1 : η1‐diazene (HN=NH) is the microscopic reverse of the proposed N2 fixation pathway, revealing the energetics of the process. Previously, Sellmann assigned the purple metastable product from two‐electron oxidation of [{Fe2+(PPr3)L1}2(μ‐η1 : η1‐N2H2)] (L1=tetradentate SSSS ligand) at −78 °C as [{Fe2+(PPr3)L1}2(μ‐η1 : η1‐N2)]2+, which would come from double PCET from diazene to sulfur atoms of the supporting ligands. Using resonance Raman, Mössbauer, NMR, and EPR spectroscopies in conjunction with DFT calculations, we show that the product is not an N2 complex. Instead, the data are most consistent with the spectroscopically observed species being the mononuclear iron(III) diazene complex [{Fe(PPr3)L1}(η2‐N2H2)]+. Calculations indicate that the proposed double PCET has a barrier that is too high for proton transfer at the reaction temperature. Also, PCET from the bridging diazene is highly exergonic as a result of the high Fe3+/2+ redox potential, indicating that the reverse N2 protonation would be too endergonic to proceed. This system establishes the "ground rules" for designing reversible N2/N2H2 interconversion through PCET, such as tuning the redox potentials of the metal sites. [ABSTRACT FROM AUTHOR]

Due to the excellent activity and stability of MnCo 2 O 4 toward the oxygen evolution reaction (OER) in acidic solution, a Pb–MnCo 2 O 4 composite anode for zinc electrowinning was prepared by embedding dispersed MnCo 2 O 4 particles into a Pb matrix in a powder metallurgy process. In this work, the phase structure, chemical composition, and morphology of the oxide layers formed on Pure-Pb and Pb–MnCo 2 O 4 were analyzed by XRD, SEM, and EDS. Galvanostatic polorization, Tafel tests, and EIS measurements were performed to investigate the anodic potential variation and OER kinetics of the Pure-Pb and Pb–MnCo 2 O 4 composite anodes. Compared with that on the Pure-Pb anode, the oxide layer on Pb–MnCo 2 O 4 is thinner, more compact, and more stable in a 160 g L−1 H 2 SO 4 solution containing 4 g L−1 Mn2+. Consequently, the Pb–MnCo 2 O 4 composite anode exhibited a much lower anode slime production (8.7 mg) during 72 h of the simulated zinc electrowinning process. Despite the smaller surface area and lower PbO 2 content of the oxide layer, the Pb–MnCo 2 O 4 composite anode presented preferable OER kinetics with a lower OER charge transfer resistance (0.729 Ω cm2) and a smaller Tafel slope (90.74 mV dec−1), which contributed to a 70 mV reduction in the anodic potential compared with that of the Pure-Pb anode. • The anodic potential of Pb–MnCo 2 O 4 composite anode is 70 mV than the Pure-Pb anode. • The oxide layer on Pb–MnCo 2 O 4 is thinner, more compact, and more stable. • Pb–MnCo 2 O 4 exhibits a smaller tafel slope and lower charge transfer resistance of OER. • The incorporation of MnCo 2 O 4 significantly reduces the production of anode slime. [ABSTRACT FROM AUTHOR]

Aviation contributes to anthropogenic climate change by emitting both carbon dioxide (CO 2) and non-CO 2 emissions through the combustion of fossil fuels. One approach to reduce the climate impact of aviation is the use of hydrogen as an alternative fuel. Two distinct technological options are presently under consideration for the implementation of hydrogen in aviation: hydrogen fuel cell architectures and the direct combustion of hydrogen. In this study, a hydrogen demand model is developed that considers anticipated advancements in liquid hydrogen aircraft technologies, forecasted aviation demand, and aircraft startup and retirement cycles. The analysis indicates that global demand for liquid hydrogen in aviation could potentially reach 17 million tons by 2050, leading to a 9% reduction in CO 2 emissions from global aviation. Thus, the total potential of hydrogen in aviation extends beyond this, considering that the total market share of hydrogen aircraft on suitable routes in the model is projected to be only 27% in 2050 due to aircraft retirement cycles. Additionally, it is shown, that achieving the potential demand for hydrogen in aviation depends on specific market prices. With anticipated declines in current production costs, hydrogen fuel costs would need to reach about 70 EUR/MWh by 2050 to fulfill full demand in aviation, assuming biofuels provide the cheapest option for decarbonization alongside hydrogen. If e-fuels are the sole option for decarbonization alongside hydrogen, which is the more probable scenario, the entire hydrogen demand potential in aviation would be satisfied according to this study's estimates at significantly higher hydrogen prices, approximately 180 EUR/MWh. • We develop a model to project liquid hydrogen demand potentials in aviation. • Global demand for hydrogen in aviation could reach about 17 million tons in 2050. • Leading to a 9% reduction in CO 2 emissions from global aviation. • Hydrogen costs must be competitive with or lower than other decarbonization options. • Simulations suggest that overall hydrogen costs will be competitive with e-fuels. [ABSTRACT FROM AUTHOR]

The reaction mechanisms of the photocatalytic reduction of CO2 to CO catalyzed by [(en)M(CO)3Cl] complexes (M = Ru, Os, en = ethylenediamine) in the presence of triethanolamine (TEOA), R3N (R = –CH2CH2OH), in DCM and DMF solvents, were studied by means of DFT/TDDFT electronic structure calculations. The geometric and free energy reaction profiles for two possible reaction pathways were calculated. Both reaction pathways studied, start with the 17e−, catalytically active intermediate, [(en)M(CO)3]˙+ generated from the first triplet excited state, T1 upon reductive quenching by TEOA which acts as a sacrificial electron donor. In the first possible pathway, TEOA− anion binds to the metal center of the catalytically active intermediate, [(en)M(CO)3]˙+ followed by CO2 insertion into the M-OCH2CH2NR2 bond. The latter upon successive protonations releases a metal 'free' [R2NCH2CH2OC(O)(OH)] intermediate which starts a new and final catalytic cycle, leading to the formation of CO and H2O while regenarating TEOA. In the second possible pathway, the 17e−, catalytically active intermediate, [(en)M(CO)3]˙+ captures CO2 molecule, forming an η1-CO2 complex. Upon 2H+/2e− successive protonations and reductions, CO product is obtained along with regenarating the catalytically active intermediate [(en)M(CO)3]˙+. The nature of the proton donor affects the reaction profiles of both mechanisms. The nature of the solvent does not affect significantly the reaction mechanisms under study. Finally, since photoexcitation and T1 reductive quenching are common to both pathways, we have srutinized the photophysical properties of the [(en)M(CO)3Cl] complexes along with their T1 excited states reduction potentials,. The [(en)M(CO)3Cl] complexes absorb mainly in the UV region while the absolute are in the range 6.4–0.9 eV. [ABSTRACT FROM AUTHOR]

Aqueous Zn metal batteries hold significant promise for large‐scale energy storage owing to their high safety and low cost. Nevertheless, severe corrosion and uncontrollable dendrite growth hinder the cyclic stability of Zn metal anodes. Herein, a porphyrin‐Zn(II) (ZnTBPP) based multifunctional artificial layer to stabilize Zn anodes by suppression of hydrogen evolution reactions is designed. This hydrophobic interfacial layer repels active water molecules and facilitates the electron transfer from Zn interface to the ZnTBPP layer, thereby increasing the inherent hydrogen evolution potential of Zn anodes. Differential charge density maps reveal that the electron cloud density of the charge transfer layer within the ZnTBPP layer is delocalized due to the electron‐withdrawing effect of Br‐containing functional groups in the ZnTBPP ligands, depleting the interfacial electrons of Zn metal anodes. As a result, H* exhibits a higher Gibbs free energy (∆GH*) of 0.75 eV on Zn with a ZnTBPP coating layer in contrast to bare Zn (0.55 eV), effectively suppressing H2 production. Specifically, the H2 evolution rate of ZnTBPP@Zn (4.06 µmol h−1 cm−2) is ≈2.2 times lower than that of bare Zn. The ZnTBPP@Zn//NaV3O8·1.5H2O full cells exhibit an ultra‐long cycling life of 10 000 cycles at 10 A g−1. [ABSTRACT FROM AUTHOR]

Rigid three‐dimensional (3D) polycyclic propellanes have garnered interest due to their unique conformational spaces, which display great potential use in selectivity, separation and as models to study through‐space electronic interactions. Herein we report the synthesis of a novel rigid propellane, trinaphtho[3.3.3]propellane triimide, which comprises three imide groups embedded on a trinaphtho[3.3.3]propellane. This propellane triimide exhibits large bathochromic shift, amplified molar absorptivity, enhanced fluorescence, and lower reduction potential when compared to the subunits. Computational and experimental studies reveal that the effective through‐space π‐orbitals interacting (homoconjugation) occurs between the subunits. Single‐crystal XRD analysis reveals that the propellane triimide has a highly quasi‐D3h symmetric skeleton and readily crystallizes into different superstructures by changing alkyl chains at the imide positions. In particular, the porous 3D superstructure with S‐shaped channels is promising for taking up ethane (C2H6) with very good selectivity over ethylene (C2H4), which can purify C2H4 from C2H6/C2H4 in a single separation step. This work showcases a new class of rare 3D polycyclic propellane with intriguing electronic and supramolecular properties. [ABSTRACT FROM AUTHOR]

In this work, by first‐principles calculations, we investigate the structural, photoelectric, and catalytic properties of g‐ZnO/Hf2CO2 vdW heterostructures to explore highly efficient photocatalysts of water splitting. Results show that the AA‐stacking g‐ZnO/Hf2CO2 vdW heterostructure (AA‐HS) with an indirect bandgap of 1.738 eV has a typical type‐II band alignment, which is benefit to effectively separate the photogenerated carriers into different layers and prevent their recombination. The conduction band minimum (CBM) and valence band maximum (VBM) of AA‐HS straddling the water redox potentials makes it satisfies the requirements of photocatalytic water splitting at pH = 7. In addition, to evaluate the photocatalytic performance of AA‐HS during oxidation evolution reaction (OER) process in water splitting, we calculated the change of Gibbs free energies of the intermediates on heterostructure under different conditions. Results show the Gibbs free energy decreases continuously at pH = 7 and U = 1.93 V. What's more, the AA‐HS has good sunlight‐absorption ability. External biaxial strain is not conducive to improving catalytic performance of AA‐HS. [ABSTRACT FROM AUTHOR]

2-Phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (PTIO•), a persistent nitronyl nitroxide radical, has been used for the detection and trapping of nitric oxide, as a redox mediator for batteries, for the activity estimation of antioxidants, and so on. However, there is no report on the reactivity of PTIO• in the presence of redox-inactive metal ions. In this study, it is demonstrated that the addition of scandium triflate, Sc(OTf)3 (OTf = OSO2CF3), to an acetonitrile (MeCN) solution of PTIO• resulted in an electron-transfer disproportionation to generate the corresponding cation (PTIO+) and anion (PTIO−), the latter of which is suggested to be stabilized by Sc3+ to form [(PTIO)Sc]2+. The decay of the absorption band at 361 nm due to PTIO•, monitored using a stopped-flow technique, obeyed second-order kinetics. The second-order rate constant for the disproportionation, thus determined, increased with increasing the Sc(OTf)3 concentration to reach a constant value. A drastic change in the cyclic voltammogram recorded for PTIO• in deaerated MeCN containing 0.10 M Bu4NClO4 was also observed upon addition of Sc(OTf)3, suggesting that the large positive shift of the one-electron reduction potential of PTIO• (equivalent to the one-electron oxidation potential of PTIO−) in the presence of Sc(OTf)3 may result in the disproportionation. When H2O was added to the PTIO•–Sc(OTf)3 system in deaerated MeCN, PTIO• was completely regenerated. It is suggested that the complex formation of Sc3+ with H2O may weaken the interaction between PTIO− and Sc3+, leading to electron-transfer comproportionation to regenerate PTIO•. The reversible disproportionation of PTIO• was also confirmed by electron paramagnetic resonance (EPR) spectroscopy. [ABSTRACT FROM AUTHOR]

Rigid three‐dimensional (3D) polycyclic propellanes have garnered interest due to their unique conformational spaces, which display great potential use in selectivity, separation and as models to study through‐space electronic interactions. Herein we report the synthesis of a novel rigid propellane, trinaphtho[3.3.3]propellane triimide, which comprises three imide groups embedded on a trinaphtho[3.3.3]propellane. This propellane triimide exhibits large bathochromic shift, amplified molar absorptivity, enhanced fluorescence, and lower reduction potential when compared to the subunits. Computational and experimental studies reveal that the effective through‐space π‐orbitals interacting (homoconjugation) occurs between the subunits. Single‐crystal XRD analysis reveals that the propellane triimide has a highly quasi‐D3h symmetric skeleton and readily crystallizes into different superstructures by changing alkyl chains at the imide positions. In particular, the porous 3D superstructure with S‐shaped channels is promising for taking up ethane (C2H6) with very good selectivity over ethylene (C2H4), which can purify C2H4 from C2H6/C2H4 in a single separation step. This work showcases a new class of rare 3D polycyclic propellane with intriguing electronic and supramolecular properties. [ABSTRACT FROM AUTHOR]

In this paper, a wideband polarization conversion metasurface is designed. Additionally, coding and chessboard metasurfaces are specifically tailored for radar cross-section reduction (RCS). Initially, a compact unit cell demonstrating exceptional polarization conversion performance is introduced, achieving a polarization conversion ratio (PCR) exceeding 90 % across frequencies ranging from 7.9 to 22.7 GHz. The PCR remains effective even when oblique incidence angles of up to 30 ∘ are utilized across this frequency band. Roger RT5880, with a thickness of 0.254 mm, serves as the substrate. An airgap is introduced between the substrate and the ground plane to enhance the polarization conversion bandwidth. This unit cell serves as the fundamental building block for subsequent metasurface configurations. To assess the scalability and effectiveness, a 36 × 36 unit array is assembled, confirming efficient polarization conversion capabilities extending to larger structures. Moreover, a 1-bit coding unit "0" and "1" are formed by the Pancharatnam-Berry phase based on the same-sized meta-atom with 90 ∘ orientations. The robustness and practicality of the design are demonstrated by creating 12 × 12 lattices and evaluating their RCS reduction potential under two distinct scenarios: a chessboard pattern and a coding-based scheme. Notably, its results indicate substantial RCS reduction across a broad frequency spectrum (7.9 to 22.7 GHz) for both configurations. This study demonstrates the wide-ranging applicability of metasurface design, making it a valuable contribution to the fields of microwave engineering, polarization control, and radar stealth technology. Owing to its simplicity, bandwidth, and versatility, this approach offers innovative solutions for diverse real-world applications. [ABSTRACT FROM AUTHOR]

Bipolar organic cathode materials (OCMs) implementing cation/anion storage mechanisms are promising for high‐energy aqueous Zn batteries (AZBs). However, conventional organic functional group active sites in OCMs usually fail to sufficiently unlock the high‐voltage/capacity merits. Herein, we initially report dynamically ion‐coordinated bipolar OCMs as cathodes with chalcogen active sites to solve this issue. Unlike conventional organic functional groups, chalcogens bonded with conjugated group undergo multielectron‐involved positive‐valence oxidation and negative‐valence reduction, affording higher redox potentials and reversible capacities. With phenyl diselenide (PhSe‐SePh, PDSe) as a proof of concept, it exhibits a conversion pathway from (PhSe)− to (PhSe‐SePh)0 and then to (PhSe)+ as unveiled by characterization and theoretical simulation, where the diselenide bonds are periodically broken and healed, dynamically coordinating with ions (Zn2+ and OTF−). When confined into ordered mesoporous carbon (CMK‐3), the dissolution of PDSe intermediates is greatly inhibited to obtain an ultralong lifespan without voltage/capacity compromise. The PDSe/CMK‐3 || Zn batteries display high reversibility capacity (621.4 mAh gPDSe−1), distinct discharge plateau (up to 1.4 V), high energy density (578.3 Wh kgPDSe−1), and ultralong lifespan (12 000 cycles) at 10 A g−1, far outperforming conventional bipolar OCMs. This work sheds new light on conversion‐type active site engineering for high‐voltage/capacity bipolar OCMs towards high‐energy AZBs. [ABSTRACT FROM AUTHOR]

Many operational parameters, either discretely or collectively, can influence the biodegradation performance towards enhancing biogas yield and quality. Among the operating parameters, organic loading rate (OLR), inoculum-substrate ratio, and carbon-nitrogen ratio (C/N) are the most critical parameters in the optimization and enhancement of biogas yield. Optimization of the biogas production processes depends on the ability of anaerobic microorganisms to respond to variations in operational parameters such as pH, redox potential, and intermediate products to enhance the biogas yield. This review article focuses on the role of process parameters, kinetic models, artificial intelligence, Aspen Plus (AP), and anaerobic digestion model no. 1 (ADM1) in optimizing biogas yield via an anaerobic codigestion (AcoD) process. The review showed that biomaterials codigestion upgraded biogas yield to the extent of 400%, and organic removal efficiency reached up to 90% compared to a single substrate. In addition, the current work has verified that the kinetic model is the most effective tool for signifying that the hydrolysis phase is the rate-limiting step, whereas AP is the most effective tool in the design and optimization of the AcoD process parameters. The reviewed kinetic and AI models show strong correlation values ranging from 0.931 to 0.9991 and 0.8700 to 0.9998, respectively. The AcoD system involves complex chemical reactions, but AP might have limitations in representing such complex chemical processes with nonideal behavior and complicated reaction mechanisms. The design and optimization of AcoD with reliable input parameters are highly limited or nonexistent. The AcoD process design with AP opens fresh research opportunities, including improved efficiency, finding appropriate retention time, and saving time, as well as finding the optimum biogas yield. This review article gives an insightful understanding of AcoD process parameter optimization and valuable strategies for policy development enhancing sustainability in the biogas sector. [ABSTRACT FROM AUTHOR]