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A family of hybrid Perovskite-oxalates ("Perovzalates") of general composition AILi3MII(C2O4)3 (A = K+, Rb+, Cs+; M = Fe2+, Co2+, Ni2+) are presented. All eight new compounds are isostructural with the previously reported examples NH4Li3Fe(C2O4)3 and KLi3Fe(C2O4)3, crystallising in the rhombohedral space group R3¯c, with a ∼11.3–11.6 Å, c ∼14.8–15.2 Å. In contrast to other families of "hybrid perovskites" such as the formates, these compounds can be regarded as closer structural relatives to inorganic (oxide) perovskites, in the sense that they contain direct linkages of the octahedral sites via bridging oxygen atoms (of the oxalate groups). It is of note, therefore, that monoatomic cations as large as Cs+ can be incorporated into the perovskite-like A sites of this structure type, which is not feasible in traditional ABO3 perovskites; indeed CsLi3Ni(C2O4)3 appears to exhibit the 'mostly tightly bound' 12-coordinate Cs+ ion in an oxide environment, according to a bond valence analysis. [ABSTRACT FROM AUTHOR]

• A cobalt/alumina catalyst was modified with tin. • The Sn-modified samples were less active for methanol production. • The methanol rate of formation correlated with H 2 adsorption capacity. • Surface formates on Sn-modified samples showed a markedly lower reactivity. Hydrocarbons are the main reaction products of syngas conversion over cobalt-based catalysts. Methanol is also produced as a minor by-product and has been proposed to be produced via a specific reaction pathway involving formates species located at the interface with the support. The poisoning of a Co/alumina catalyst with Sn was studied here and showed to induce a strong decline in methanol production, similar to that of hydrocarbons. The addition of Sn did not prevent the formation of formates as observed by operando diffuse reflectance FT-IR spectroscopy. However, the reactivity of formates was markedly lowered in the presence of Sn. We propose that these observations have two possible origins. Firstly, Sn addition reduced significantly the H 2 adsorption capacity of the Sn-modified samples. Hydrogen, which is required for the hydrogenation of formates to methanol, is probably activated on the cobalt metal particles, some sites of which were strongly poisoned by Sn. Secondly, Sn addition could also have specifically poisoned interfacial sites, where the most reactive formates are present. [ABSTRACT FROM AUTHOR]

This article is devoted to the description of the development of a technological installation designed to implement an improved method for the separation of polyols, for example, neopentylglycol or trimethylolpropane (etriol), and sodium or calcium formates. The process developed involves adding an organic solvent to the mixture of substances to be separated. In this case, the polyhydric alcohol is dissolved, and sodium or calcium formate crystallizes. The separation of sodium formate or calcium from a solution of a polyhydric alcohol in an organic solvent is carried out by filtration. The organic solvent used is recycled. Then the solution is cooled and the polyol is crystallized. As an organic solvent, an aromatic solvent is used, for example, toluene. An organic solvent is added to the mixture of substances to be separated and the mixture is heated to boiling point. At the same time, the mixture is dehydrated. After distillation of the water, the organic solvent is recycled. Next, carry out the crystallization of sodium formate or calcium, insoluble in an organic solvent, and the dissolution of the polyol. The developed method allows for increasing the yield of well-purified target products. To implement it, simple and reliable installation for the separation of polyhydric alcohols, sodium formate or calcium formate has been proposed. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Ni/CeO 2 -SiO 2 -P and -C with different structures were used for DRM. • The interaction model between Ni and CeO 2 affected the catalytic performance. • Ni/CeO 2 -SiO 2 -P exhibited superior low-temperature activity and H 2 /CO ratio. • More reactive oxygen species on Ni/CeO 2 -SiO 2 -P improved the stability. • Formate species were observed on Ni/CeO 2 -SiO 2 -P. Abstract Manipulating interfacial structure and interaction between metal and supports is important for many heterogenous catalysts with the aim at achieving high and stable activity and selectivity. In this work, two kinds of Ni/CeO 2 -SiO 2 catalysts are fabricated and designed, including CeO 2 close contact with Ni nanoparticles (Ni/CeO 2 -SiO 2 -P) or CeO 2 away from Ni nanoparticles (Ni/CeO 2 -SiO 2 -C) for dry reforming of methane. Ni/CeO 2 -SiO 2 -P exhibits superior low-temperature activity and H 2 /CO ratio compared with Ni/CeO 2 -SiO 2 -C. CO 2 and CH 4 conversions on the former (87.3% and 78.5%) are higher than those of the later (80.5% and 67.8%) at 700 °C. Meanwhile, Ni/CeO 2 -SiO 2 -P is stable in the long-term study whereas Ni/CeO 2 -SiO 2 -C presents poor stability and the activity dramatically decreases in 10 h. The improved performance and stability on Ni/CeO 2 -SiO 2 -P originates from more reactive oxygen species and more accessible sites for the formate species on the metal–support interface. The reaction order and activation energy of both catalysts are also calculated in the kinetic studies. This work opens up new possibilities for exploring the effect of metal–support on designing highly efficient heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

It is well known that cofactors play a key role in the production of different compounds in bioconversion processes, while the high cost of cofactors limits their usage in industrial applications. In the present study, a NADH regeneration system was successfully developed in Lactobacillus plantarum by expressing the fdh gene coding for formate dehydrogenase (FDH) from Candida boidinii. Results indicated that the FDH was expressed with the highest activity of 0.82 U/mg of protein when cells entered early stationary phase. In addition, the expression of FDH increased the intracellular level of NADH and NADH/NAD+ ratio in L. plantarum, and therefore, enhanced the NADH-dependent production of 3-phenyllactic acid (PLA) in repeated and fed-batch bioconversions. In brief, the results demonstrate that the NADH regeneration by expressing FDH is a promising strategy for producing NADH-dependent microbial metabolites in L. plantarum. [ABSTRACT FROM AUTHOR]

• A mono-alkyl pyrocarbonate-bipyridinium salt intermediate is found to play a role in activating CO 2 to synthesize ethyl formate as a value-added product. • A tandem esterification and hydrogenation is realized by introducing both the basic bipyridine sites for CO 2 activation and metallic Pd nanoparticles for hydrogenation in the same nano-cavity of a designer metal-organic framework (MOF). • This design leads to a high catalytic activity to generate ethyl formate (HCO 2 Et) (1333 umol/g cat /h) with 93.5% selectivity at 412 K with a turnover frequency of HCO 2 Et per Pd atom up to 22.2 h-1. CO 2 activation and conversion are of significant interest. Here we report a mono-alkyl pyrocarbonate-bipyridinium salt intermediate to activate CO 2 for synthesizing ethyl formate as a value-added product via tandem esterification and hydrogenation. The required basic bipyridine sites for CO 2 activation and metallic Pd nanoparticles for hydrogenation were assembled in the same nano-cavity of a designer metal–organic framework (MOF). This MOF hybrid exhibits a high catalytic activity to generate ethyl formate (HCO 2 Et) (1333 μmol/g cat /h) with 93.5% selectivity at 412 K. The turnover frequency of HCO 2 Et based on the number of exposed Pd atoms is up to 22.2 h−1, higher than those of other catalysts previously reported for generating alkyl formates from CO 2 under similar conditions. [ABSTRACT FROM AUTHOR]

An iridium (III) complex based on a PONOP pincer ligand (PONOP=2,6‐bis(di‐tert‐butylphosphinito)pyridine) is a versatile catalyst for both electro‐reduction of CO2 to formate and formate electro‐oxidation to CO2. The electro‐reduction of CO2 in acetonitrile is very efficient and selective, and the Faradaic efficiency for formate was 97 % and the turnover frequency (TOF) was as high as 67 s−1. In addition, the complex is an effective electrocatalyst for formate electro‐oxidation with apparent TOF of 4.8 s−1 (0.06 M formate), and CO2 was the sole product. The catalyst was stable for 35 h of electrolysis. It can serve as a single catalyst for the roundtrip conversion between CO2 and formate with potential for electrochemical energy storage. Electrochemical and NMR spectroscopic studies suggested that the hydride species is critical for the bifunctional reactivity. [ABSTRACT FROM AUTHOR]

Abstract Liquid-liquid equilibrium (LLE) data for poly (ethylene glycol) (PEG) of different molecular weights (600, 1500, 3000, 6000) + sodium formate (NaCHO 2), potassium formate (KCHO 2) + water at different temperatures (298.15 and 308.15 K) and for PEG (1500) + sodium formate + water at different pH values (8.05, 9.06, 10.92), were determined experimentally. The tie lines and plait point are reported at different PEG molecular weight, pH, temperature and type of cation. Furthermore, the effect of those parameters on binodal curve, tie-line length (TLL) and slope of tie line (STL) are discussed in detail by comparing the results to that of literature data. The effective excluded volume (EEV) values obtained from the LLE data were used to study the effect of the parameters on the binodal curves. The phase composition and the tie-lines' ends were obtained by measuring the density (ρ) and refractive index ( n D ). Furthermore, the binodal curves and the tie-line compositions were well-fitted by using some semi empirical equations. Highlights • ATPS were prepared combining PEG (600, 1500, 3000, 6000) with NaCHO 2 , KCHO 2. • The heterogeneous region increases with temperature and PEG Mw. • The effect of pH on the size of the heterogeneous region can be neglected. • The EEV increases with the rise on pH, temperatures, and PEG Mw. • The effect of Na+ is more effective in inducing phase separation compared to K+. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Formate-assisted pyrolysis is an effective way for the kraft lignin decomposition. • Monophenols and polyphenols were the main products of kraft lignin with formates. • Nickel formate showed highest selectivity of polyphenols and hydrocarbons. • Nickel formate showed the synergetic effect of hydrogen donor and nickel catalysis. Abstract The effect of sodium formate (SF), calcium formate (CF) and nickel formate (NF) as additives on analytical pyrolysis performance of kraft lignin was conducted. The results showed that these formates promoted the releasing of volatiles, leading to the rapid degradation of kraft lignin. High relative content of monophenols (53.77%), especially of guaiacol (23.65%), were achieved from the pyrolysis of pure lignin. The relative content of guaiacol was dramatically decreased after the adding of formates in kraft lignin. The relative content of polyphenols such as 3-methylcatechol and 4-methylcatechol reached to 16.97%, 16.23% and 21.95% with the formates of SF, CF and NF, respectively. The NF showed the highest selectivity of polyphenols and hydrocarbons. The increase of polyphenols and hydrocarbons from NF was the synergetic effect of the hydrogen radical reaction from the formic functional groups under the catalysis of Ni and/or NiO produced from the NF pyrolysis process. [ABSTRACT FROM AUTHOR]

Glycolic acid (GA), as important building block of biodegradable polymers, has been synthesized for the first time in excellent yields at room temperature by selective oxidation of 1,3‐dihyroxyacetone (DHA) using a cheap supported Cu/Al2O3 catalyst with single active CuII species. By combining EPR spin‐trapping and operando ATR‐IR experiments, different mechanisms for the co‐synthesis of GA, formates, and formamides have been derived, in which.OH radicals formed from H2O2 by a Fenton‐like reaction play a key role. Clean and green by radicals: 1,3‐Dihydroxylacetone, a biomass‐based platform molecule has been oxidized with 100 % carbon atom efficiency at room temperature to valuable glycolic acid, formamides and formates by a cheap non‐noble metal catalyst. Radical‐based mechanisms were discovered by in situ EPR with spin traps and operando ATR‐IR spectroscopy. [ABSTRACT FROM AUTHOR]

Abstract Temperature dependences of the frequencies for the Raman modes of ν (NH 2), ν s (CH 3), ν 1 (HCOO−), ν S (CNN) and IR mode of ρ (NH 2) are calculated in particular, for MHyMn close to the phase transition temperature (T C = 220 K) in the family of compounds CH 3 NH 2 NH 2 M(HCOO) 3 , MHyM with M = Mn, Mg, Fe and Zn. By assuming Raman and infrared frequency as an order parameter, this calculation is performed from the molecular field theory by using the experimental data from the literature. We also calculate the damping constant (FWHM) from the order parameter (Raman and IR frequency of those modes) by using the pseudospin (MHy+ cations)-phonon coupled model (PS) and the energy-fluctuation model (EF) for methylhydrazinium metal formate frameworks. Expressions of the damping constant from both models are fitted to the observed FWHM data for the Raman and infrared modes studied for these metal formates. Our results show that the anomalous behaviour of the Raman and IR frequencies of those modes, except the ν S (CH 3) Raman mode which are associated with the phase transition can be described adequately by the molecular field theory in MHyM, as observed experimentally. Also, the damping constant calculated from the PS and EF models can explain the observed FWHM of those Raman and IR modes studied in methylhydrazinium metal formate frameworks. Highlights • Raman and IR frequencies are calculated from the molecular field theory for MHyM. • FWHM of those Raman and IR modes are calculated from the PS and EF models for MHyM. • Experimental data from the literature are used for the modes of MHyM. • Molecular field theory (frequency), PS and EF models (FWHM) are applicable to the MHyM. [ABSTRACT FROM AUTHOR]

A single device combining the functions of a CO2 electrolyzer and a formate fuel cell is a new option for carbon‐neutral energy storage but entails rapid, reversible and stable interconversion between CO2 and formate over a single catalyst electrode. We report a new catalyst with such functionalities based on a Pb–Pd alloy system that reversibly restructures its phase, composition, and morphology and thus alters its catalytic properties under controlled electrochemical conditions. Under cathodic conditions, the catalyst is relatively Pb‐rich and is active for CO2‐to‐formate conversion over a wide potential range; under anodic conditions, it becomes relatively Pd‐rich and gains stable catalytic activity for formate‐to‐CO2 conversion. The bifunctional activity and superior durability of our Pb–Pd catalyst leads to the first proof‐of‐concept demonstration of an electrochemical cell that can switch between the CO2 electrolyzer/formate fuel cell modes and can stably operate for 12 days. [ABSTRACT FROM AUTHOR]

Abstract The disadvantage of anion ionomer that possesses low hydroxide conductivity, and thermal and chemical instability hinders the development of the high-performance anion-exchange membrane direct liquid fuel cells. Instead of adding additional base and synthesizing high-conductivity ionomer material, by gaining insight into species transports, herein, we propose an anion-ionomer-free anion-exchange membrane direct formate fuel cell (AEM DFFC). Experimental result reveals that this conceptual anion-ionomer-free AEM DFFC can operate stably within a 6-h constant-current discharge at 10 mA cm−2, mainly because formate hydrolysis renders a high OH− conductivity. It was also found that the anion-ionomer-free AEM DFFC yields a peak power density as high as 41 mW cm−2 at 40 °C, 40% higher than that of the conventional quaternary ammonia polysulfone anion-ionomer AEM DFFC. This can be attributed to the fact that the OH−-containing formate solution facilitates the mass and charge transports, thereby enlarging the triple-phase boundary for both anodic formate oxidation reaction and cathodic oxygen reduction reaction. Graphical abstract Image 1 Highlights • An anion-ionomer-free AEM direct formate fuel cell was proposed. • A stable 6-h constant-current discharge was achieved at 10 mA cm−2. • Formate hydrolysis renders the mass and charge transport media. [ABSTRACT FROM AUTHOR]

Highlights • HILIC-MS/MS was used for the determination of 16 coccidiostats in muscle and eggs. • Good accuracy and remarkably low LOQs were achieved in very short analysis time. • 82 meat & egg samples were analysed through the Greek National Residue Control Plan. • New data were obtained regarding the occurrence of coccidiostat residues in Greece. Abstract A simple, sensitive and efficient confirmatory method was developed and validated for the determination of 16 coccidiostats in animal tissues and eggs using hydrophilic interaction liquid chromatography–tandem mass spectrometry (HILIC-MS/MS). The sample preparation consisted of a solid-liquid extraction with ACN and dispersive SPE cleanup with MgSO 4 and C 18. Analysis was realized in an Acquity BEH HILIC silica column, in SRM mode. Both positive and negative ionization was performed, using polarity switching. Isocratic elution was used with a mobile phase of ACN: aqueous ammonium formate 1 mM with 0.1% formic acid (80:20, v/v). Method validation was performed in eggs, poultry, bovine, ovine, porcine and rabbit tissue and exceptionally low LODs were achieved, varying from 0.004 μg kg−1 (decoquinate in porcine tissue) to 0.560 μg kg−1 (halofuginone in eggs). The developed methodology was applied in 82 muscle and egg samples through the Greek National Residue Control Plan for coccidiostats. [ABSTRACT FROM AUTHOR]

This work reports the one‐pot enzymatic cascade that completely converts l‐arabinose to l‐ribulose using four reactions catalyzed by pyranose 2‐oxidase (P2O), xylose reductase, formate dehydrogenase, and catalase. As wild‐type P2O is specific for the oxidation of six‐carbon sugars, a pool of P2O variants was generated based on rational design to change the specificity of the enzyme towards the oxidation of l‐arabinose at the C2‐position. The variant T169G was identified as the best candidate, and this had an approximately 40‐fold higher rate constant for the flavin reduction (sugar oxidation) step, as compared to the wild‐type enzyme. Computational calculations using quantum mechanics/molecular mechanics (QM/MM) molecular dynamics (MD) showed that this improvement is due to a decrease in the steric effects at the axial C4‐OH of l‐arabinose, which allows a reduction in the distance between the C2‐H and flavin N5, facilitating hydride transfer and enabling flavin reduction. [ABSTRACT FROM AUTHOR]

Abstract Practical preparations of dichloromethyl alkyl ethers are described, based on the reaction of alkyl formates with oxalyl chloride in the presence of N -methylformanilide. The method involves a simple procedure that does not require the use of harmful reagents. Dichloromethyl propyl and dichloromethyl butyl ethers represent secure synthetic equivalents to dichloromethyl methyl ether. Formylations of both electron-deficient and electron-rich aromatics with these dichloromethyl alkyl ethers in the presence of AlCl 3 , FeCl 3 , or TiCl 4 have been systematically investigated. A plausible mechanism of formylation is discussed. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Hydrogenation of CO2 to formate with H2 in the absence of transition metal is a long‐standing challenge in catalysis. The reactions between tris(pentafluorophenyl)borane (BCF) and K2CO3 (or KHCO3) are found to form a Lewis pair (K2[(BCF)2−CO3]) which can react with both H2 and CO2 to produce formate. Based on these stoichiometric reactions, the first catalytic hydrogenation process of CO2 to formate using transition metal free catalyst (BCF/M2CO3, M=Na, K, and Cs) is reported. The highest TON value of this catalytic process is up to 3941. Further research revealed the reaction mechanism in which the Lewis pair enables the splitting of H2 and the insertion of CO2 into the B−H bond. [ABSTRACT FROM AUTHOR]

Highlights • Formate salts were explored as new additives in the CaO-activated fly ash system. • The effect of formate on strength was dependent on the formate salt's cation type. • The use of Ca(HCOO) 2 was significantly effective in improving strength. • The use of Ca(HCOO) 2 notably increased C-S-H and reduced overall pore sizes. Abstract This study investigated whether three formate salt additives (Ca(HCOO) 2 , NaHCOO, and KHCOO) could improve the strength of a CaO-activated fly ash (FA) system. Various tests were conducted to verify the effects of the formate salts including compressive strength, X-ray diffraction (XRD), thermogravimetric (TG) analysis, solid-state 27Al magic-angle spinning nuclear magnetic resonance (MAS-NMR) spectroscopy, and mercury intrusion porosimetry (MIP). The results showed that the addition of Ca(HCOO) 2 significantly strengthened the FA binder system by (1) substantially increasing C-S-H formation and (2) measurably reducing overall pore size. However, adding NaHCOO or KHCOO was much less advantageous to strength improvement because although helpful in dissolving FA, the high pH environment caused by their reaction with CaO inhibited further dissolution of CaO, which was the main activator used in this study. [ABSTRACT FROM AUTHOR]

The electrochemical reduction of CO2 provides an alternative carbon‐neutral path for renewable synthesis of fuels and value‐added chemicals. This work demonstrates that dendritic, bimetallic Cu–Bi electrocatalysts with nanometer‐sized grains are capable of formate generation with a high selectivity. Optimizing composition of electrocatalyst could achieve a faradic efficiency of 90 % at −0.8 to −0.9 VRHE, and a partial current of more than 2 mA cm−2. The combination of Cu with Bi enables modulation of the adsorption strength of intermediates. This leads to an increased selectivity and suppressed formation of spurious species, especially hydrogen and CO. Comparison of product distribution for Cu–In versus Cu–Bi indicated that Bi is essential to induce a favorable adsorption configuration of the intermediate species and to promote formate production. Getting CO2 in format(e)ion: Cu–Bi bimetallic electrocatalysts for reduction of gaseous CO2 are synthesized by using electrodeposition. The efficiency, current density, and product selectivity of the catalysts are highly dependent on the composition and applied reduction potential. Optimized incorporation of Bi in Cu can achieve >90 % faradaic efficiency for formate production with a high product selectivity. [ABSTRACT FROM AUTHOR]

Abstract The formic acid oxidation reaction has been studied in concentrated perchloric acid solutions (up to 9.14 M (60%)) on the Pt (111) surface to explore the relationships between interfacial properties and kinetics. It is found that, as the concentration of perchloric acid in the supporting electrolyte increases, the current markedly decreases, making it possible to detect adsorbed formate on the surface by voltammetric methods. With the aid of DFT calculations, it is shown that the diminution in current is the result of two opposing factors: the reduction in the concentration of free formate in solution and electrode charge effects which encourage the adsorption of formate in a particular configuration. Additionally, the electrochemical behavior under highly acidic conditions suggests the formation of clathrate structures and emphasizes the relevance of the water structure effect in electrode adsorption processes. Highlights • Oxidation currents for formic acid diminish as the pH is made more acidic. • The net current is the result of two opposing effects: surface charge and concentration of free formate. • In highly acidic conditions clathrates are formed. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: Self‐assembly of the [Mo(CN)7]4– anion and the Mn2+ ion in the aqueous solution containing ammonium formate results in a new coordination polymer, {(NH4)3[(H2O)Mn3(HCOO)][Mo(CN)7]2·4H2O}n. Single crystal X‐ray analysis revealed a very complicated three‐dimensional (3D) framework, where both the [Mo(CN)7]4– and the formate anions act as bridges between the MnII centers. Magnetic measurements revealed that this compound displays ferrimagnetic ordering below 70 K. Competing antiferromagnetic interactions between the spin carriers might lead to spin frustration and non‐linear alignment of the magnetic moments. Specifically, this compound is the first mixed [Mo(CN)7]4–/HCOO– bridged molecule magnet. The first complex containing both the [Mo(CN)7]4– and the formate as the bridges has been synthesized and characterized. This compound is a ferrimagnet with a critical temperature of 70 K. [ABSTRACT FROM AUTHOR]

Highlights • Potassium and calcium brines extend the shear-thinning behaviour of xanthan. • Thermorheological behaviour of xanthan depends on the type of salt in the brine. • Formate brine shifts the order/disorder transition of xanthan to high temperature. Abstract Xanthan gum solutions are used in the oil industry for flooding, drilling and completion operations. The stabilization of the structure of xanthan gum solutions in presence of salts increases the value of both the order-disorder transition temperature and the gel strength. This effect is very important in order to design drilling and completion fluids since not only density and viscosity of the fluid can be improved by increasing the concentration of salts but also the range of temperature where the solution shows viscoelastic behaviour can be extended. This paper presents results from a study on the rheological behaviour of xanthan gum solutions in different saturated brines. Chloride and formate potassium brines not only increase the viscosity of the solution but also extend the shear thinning behaviour to temperatures near 200 °C, maintaining a simple relaxation mechanism over the whole range of temperature where the ordered conformation dominates the rheological behaviour. [ABSTRACT FROM AUTHOR]

Summary: Interspecies cross‐feeding is a fundamental factor in anaerobic microbial communities. In the human colon, formate is produced by many bacterial species but is normally detected only at low concentrations. Ruminococcus bromii produces formate, ethanol and acetate in approximately equal molar proportions in pure culture on RUM‐RS medium with 0.2% Novelose resistant starch (RS3) as energy source. Batch co‐culturing on starch with the acetogen Blautia hydrogenotrophica however led to the disappearance of formate and increased levels of acetate, which is proposed to occur through the routing of formate via the Wood Ljungdahl pathway of B. hydrogenotrophica. We investigated these inter‐species interactions further using RNAseq to examine gene expression in continuous co‐cultures of R. bromii and B. hydrogenotrophica. Transcriptome analysis revealed upregulation of B. hydrogenotrophica genes involved in the Wood‐Ljungdahl pathway and of a 10 gene cluster responsible for increased branched chain amino acid fermentation in the co‐cultures. Cross‐feeding between formate‐producing species and acetogens may be a significant factor in short chain fatty acid formation in the colon contributing to high rates of acetate production. Transcriptome analysis also indicated competition for the vitamin thiamine and downregulation of dissimilatory sulfate reduction and key redox proteins in R. bromii in the co‐cultures, thus demonstrating the wide‐ranging consequences of inter‐species interactions in this model system. [ABSTRACT FROM AUTHOR]

The effect of small additives of manganese, iron, cobalt, and nickel oxides on the oxidation of aluminum powder of ASD-4 grade while heating in air is studied. Composites of Al/MOx were prepared by impregnating the metal powder with saturated solutions of M(HCOO)2 ⋅ 2H2O (M = Mn, Fe, Co, and Ni) formates and thermal treatment of the mixtures in air with a maximum annealing temperature of 375°C. It has been established that the effect of modifiers on the intensity of oxidation depends on the nature of the interfacial interaction on the surface of particles. The formation of a liquid phase in the interaction of aluminum oxides and iron leads to the loss of the protective properties by the barrier layer of oxidation products and acceleration of the process. [ABSTRACT FROM AUTHOR]

In this work, we present the development of a method for the determination of acetate and formate in vegetable oils by ion chromatography with conductometric detection following their extraction from samples using a diluted KOH solution. The extraction procedure was optimized using a multivariate approach. The application of a 2 4 full factorial design showed that the mass of sample, extraction time, and KOH concentration presented significant influence on the extraction of both acetate and formate, whereas the temperature presented little influence on the process. As a result, we set the extraction temperature at 22 °C and performed the multivariate optimization of the other variables using a Doehlert design. The optimum conditions were: 4.8 g of sample, 8 mmol L −1 KOH solution and 19 min extraction time. Six samples of vegetable oils (soybean, corn, canola, sunflower and olive) were analyzed and recovery tests provided recovery percentages in the range of 82–118%. [ABSTRACT FROM AUTHOR]

A critical challenge in electrocatalytic CO2 reduction to renewable fuels is product selectivity. Desirable products of CO2 reduction require proton equivalents, but key catalytic intermediates can also be competent for direct proton reduction to H2. Understanding how to manage divergent reaction pathways at these shared intermediates is essential to achieving high selectivity. Both proton reduction to hydrogen and CO2 reduction to formate generally proceed through a metal hydride intermediate. We apply thermodynamic relationships that describe the reactivity of metal hydrides with H+ and CO2 to generate a thermodynamic product diagram, which outlines the free energy of product formation as a function of proton activity and hydricity (ΔGH-), or hydride donor strength. The diagram outlines a region of metal hydricity and proton activity in which CO2 reduction is favorable and H+ reduction is suppressed. We apply our diagram to inform our selection of [Pt(dmpe)2](PF6)2 as a potential catalyst, because the corresponding hydride [HPt(dmpe)2]+ has the correct hydricity to access the region where selective CO2 reduction is possible. We validate our choice experimentally; [Pt(dmpe)2](PF6)2 is a highly selective electrocatalyst for CO2 reduction to formate (>90% Faradaic efficiency) at an overpotential of less than 100 mV in acetonitrile with no evidence of catalyst degradation after electrolysis. Our report of a selective catalyst for CO2 reduction illustrates how our thermodynamic diagrams can guide selective and efficient catalyst discovery. [ABSTRACT FROM AUTHOR]

Highlights • Terpinyl formate, safety assessment based on RIFM's criteria. • Safety assessment based on 7 human health endpoints plus environmental. • All endpoints were cleared using target data, read-across, and/or TTC. [ABSTRACT FROM AUTHOR]

Highlights • 3a,7-Methano-3aH-cyclopentacycloocten-3-ol, decahydro-1,1,7-trimethyl-, formate, safety assessment based on RIFM's criteria. • Safety assessment based on 7 human health endpoints plus environmental. • All endpoints were cleared using target data, read-across, and/or TTC. [ABSTRACT FROM AUTHOR]

Highlights • Octyl formate, safety assessment based on RIFM's criteria. • Safety assessment based on 7 human health endpoints plus environmental. • All endpoints were cleared using target data, read-across, and/or TTC. [ABSTRACT FROM AUTHOR]

Highlights • Hexyl formate, safety assessment based on RIFM's criteria. • Safety assessment based on 7 human health endpoints plus environmental. • All endpoints were cleared using target data, read-across, and/or TTC. [ABSTRACT FROM AUTHOR]

In this paper, Bi2O3 electrocatalysts for the electroreduction of CO2 to formate were synthesized with different morphologies, including nanoparticles and thin nanorods. Comparatively, Bi2O3 nanoparticles have higher catalytic activity than Bi2O3 thin nanorods. The Faradaic efficiency of formate formation at a moderate potential of −1.2 vs. RHE in aqueous solution could reach 91 %. In addition, a maximum current density for formate production of up to 22 mA cm−2 was achieved, which is almost 3 times higher than that of Bi2O3 thin nanorods. In particular, the catalytic activity of the Bi2O3 nanoparticle catalyst was almost stable over a 23‐hour period of electrolysis, exhibiting its application prospect in the electroreduction of CO2 to formate. Upcycling: nanoparticles and thin nanorods of Bi2O3 as catalysts for the electroreduction of CO2 to formate are synthesized. The Bi2O3 nanoparticles show higher catalytic activity than the thin nanorods. A Faradaic efficiency of 91 % at a moderate potential of −1.2 vs. RHE is found in aqueous solution. A maximum current density of up to 22 mA cm−2 is achieved, with a stable activity over a 23‐hour period of electrolysis. [ABSTRACT FROM AUTHOR]

The pulsed supersonic jet expansion microwave spectra of the parent and all three 13C mono-substituted isotopologues of methyl trifluoroacetate have been measured in the 6.5-18 GHz range. All observed transitions are split into two component lines, due to the internal rotation of the methyl group. The corresponding barrier has been determined to be V 3 = 4.379(3) kJ/mol. Structural information has been obtained from the 12 available rotational constants. [ABSTRACT FROM AUTHOR]

• Three novel FDHs with higher catalytic activity toward sodium bicarbonate including Fm FDH, Ks FDH and Ss FDH were obtained. • Ss FDH has greater potential in CO 2 reduction. • Catalytic mechanism of reducing CO 2 to formate was explained using bioinformatic and computational biochemical methods. Formate dehydrogenase (FDH, EC 1.17.1.9) belongs to the class of d -2‑hydroxy acid dehydrogenases and is widely found in bacteria, archaea, yeast, fungi, plants and vertebrates. In recent years, the inverse reduction reaction of carbon dioxide to formate catalyzed by FDH has attracted widespread interest. However, the low catalytic activity has greatly limited its industrial application. In this work, three novel FDHs including Fm FDH, Ks FDH and Ss FDH, were discovered. Ss FDH showed relatively high catalytic activity toward CO 2 conversion. The enzymological properties of the enzymes were characterized, and the catalytic mechanism of reducing CO 2 to formate was investigated using bioinformatic and computational biochemical tools. The results of this work provide new insights into the function, structure and application of FDH in reducing CO 2 to formate. [Display omitted] [ABSTRACT FROM AUTHOR]