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Aim and Objective: A high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for determining hypaphorine, a potential agent for treating osteoclast- based bone loss, was developed and validated in rat plasma. Materials and Methods: Plasma samples were pretreated by the protein precipitation. Chromatographic separation was performed using an Inertsil ODS-3 column (50 mm × 4.6 mm, 5 μm). The mobile phase consisted of water (containing 0.1% formic acid) and acetonitrile in a gradient mode at a flow rate of 0.5 mL/min. The transitions from protonated precursor ion [M + H]+ to the particular daughter ion were acquired using selected reaction monitoring (SRM). The mass transitions of hypaphorine and IS were found to be 247 → 188 and m/z 219 → 188, respectively. The method was validated in terms of selectivity, linearity, accuracy and precision, extraction recovery and matrix effect, stability, and carryover. Results: It showed good linearity over the range of 1-2000 ng/mL (R2 = 0.9978). The intra-batch accuracy was within 93.95-105.81%, and the precision was within 4.92-11.53%. The inter-batch accuracy was within 96.18-100.39% with a precision of 6.22-11.23%. The extraction recovery and matrix factors were acceptable. Conclusion: The simple and rapid method was successfully applied to the pharmacokinetic study in rats following oral administration of hypaphorine at the doses of 0.5, 1.5, and 4.5 mg/kg.

This study performed catalytic depolymerization of alkali lignin over Ni-based catalysts. Effects of different promoters (Zr and W), Ni loadings, reaction temperatures, and the addition of formic acid and catalyst on lignin conversion and products distribution were all investigated. The result showed that the highest oil yield (40.1% (mass)) was obtained at 240 °C over Ni1.2/γ-Al2O3 promoted by Zr and W species. Quantitative analysis indicates that Zr and W species prefer to lignin depolymerization while Ni active phase prefer to hydrodeoxygenation and hydrogenation. The interconversion of products derived from lignin depolymerization was determined by gas chromatography-mass spectrometer, which demonstrated that phenolic compounds were dominant products in all lignin derived bio-oils, wherein the proportion of vanillin was highest (65.7%) at 180 °C, while that of alkyl guaiacols increased with the increase of temperature (from 12.45% at 180 °C to 66.67% at 240 °C). Residual lignin obtained after lignin depolymerization was also investigated for detecting differences on functional groups, wherein the disappearing peaks at 1511 cm–1 (stretching of aromatic rings), 1267, 1215 and 1035 cm–1 (vibrations of guaiacyl and syringyl units) were detected by Fourier transform infrared spectrometry. Additionally, the higher O/C ratio measured by elemental analysis also confirmed that alkali lignin was depolymerized effectively under mild conditions.

Background: The fruit pulp decoction of Crescentia cujete, commonly known as calabash, is traditionally used for the treatment of several respiratory diseases and is available as syrup formulations. Unfortunately, there is no detailed investigation on analytical methods for warranting the quality of these products. Aim and objective: To develop and validate an appropriate analytical method for the simultaneous quantification of transcinnamic acid, 4-hydroxybenzoic acid, verbascoside and 6-epi-aucubin in the decoction and commercial cough syrups of Crescentia cujete fruit. Materials and methods: A reversed-phase ultra-high-performance liquid chromatographic method coupled to a diode array detector (UPLC-DAD) was validated following the ICH guidelines. The chromatographic analysis was performed using a C18 column, the mobile phase system consisted of water and acetonitrile containing 0.1% formic acid, and UV chromatograms were recorded from 200 to 400 nm. Results: A new UPLC-DAD method was validated for the simultaneous quantification of trans-cinnamic acid, 4- hydroxybenzoic acid, verbascoside and 6-epi-aucubin in calabash-derived products. After successful validation, this method was applied for the quantification of the selected chemical markers in an in-house decoction and three commercial cough syrups. Among the selected chemical markers, 6-epi-aucubin was the main compound in the calabash decoction, while trans-cinnamic acid and 4-hydroxybenzoic acid were the major compounds in the commercial products. Verbascoside and 6-epi-aucubin were below the limit of quantification in all syrup samples. Conclusion: The proposed method was successfully applied for the analysis of three commercial syrup formulations and can be useful for standardization and quality control of raw and pharmaceutical calabash preparations.

In this work, mixed oxides Al2O3-TiO2-ZrO2 were evaluated varying their composition (% w/w) for the conversion of monosaccharides (fructose and glucose) to 5-hydroxymethylfural (HMF). Materials were characterized using Thermogravimetric Analysis and Differential Scanning Calorimetry (TGA-DSC), Nitrogen Physisorption (N2), X-ray Diffraction (XRD), RAMAN Spectroscopy, DRS UV-Vis Spectroscopy, Infrared Spectroscopy (FTIR), SEM, TEM, FTIR-Pyridine and Temperature Programmed Desorption of CO2 (TPD-CO2). The reactions were carried out at 175 °C and 30 bar of Ar pressure in a biphasic system (THF/H2O) for 3 h, obtaining a 78% maximum yield of HMF from the glucose and 63% yield from fructose. The materials studied carried out a direct dehydration of the monosaccharides to HMF in 30 minutes of reaction and were obtained as intermediates to dehydrate levulinic acid (LA) and formic acid (FA), these intermediates were analyzed and eluted using 1H- NMR technique.

Trazodone (TZD) is a tetracyclic serotonin antagonist and reuptake inhibitor that is used as a second-generation phenylpiperazine antidepressant. However, the plasma concentrations of TZD have shown individual variations in clinical practice. Quantification of TZD plasma concentrations may be an effective and valuable method to balance the clinical efficacy and adverse reactions. This study aimed to establish a novel liquid chromatography coupled with mass spectrometry (LC-MS) assay for measuring TZD concentrations in human plasma for therapeutic drug monitoring (TDM).After protein precipitation with acetonitrile, LC-MS quantification of TZD was performed in the multiple reaction monitoring mode with chromatographic separation using a mobile phase of MeOH and 0.1% formic acid in water. This method validation intends to investigate specificity, sensitivity, linearity, precision, accuracy, recovery, matrix effect, and stability according to United states food and drug administration guidelines.This method showed good selectivity because no interfering peaks were observed in the plasma samples during the 2-minute run time. The range of the calibration curve was 1-3000 ng/mL. The detection and quantification limits were 0.3 and 1 ng/mL, respectively. The intraday and interday accuracies were 96.5%-103.4%, with precision relative SD% values of5%, except for the limit of quality. The mean TZD recovery from human plasma was 95.4%-104.5%. Finally, this method was successfully applied to TDM in 20 patients. The TZD plasma concentrations of the patients ranged between 21.5 and 2267.3 ng/mL.A novel analytical method was established to measure TZD by LC-MS coupled with an automatic 2-dimensional liquid chromatograph mass spectrometer coupler 9500 (LC-MS/MS-Mate 9500), which is superior to the ordinary LC-MS system in separation, transport, anti-interference, sensitivity, and quantitative analysis stability.

Highlights • Supported liquid extraction is easy to use as visual phase separation isn't needed. • Automated sample preparation allows fast sample process and subsequent analysis. • Automated liquid handling coupled with LC-MS/MS as high-throughput method. • Washout gradient in LC method removes strongly retaining compounds from the column. • Sensitive method of 1.08/1.41 ng/ml for amodiaquine/desethylamodiaquine., Amodiaquine is a drug used for treatment of malaria and is often used in combination with artesunate in areas where malaria parasites are still susceptible to amodiaquine. Liquid chromatography tandem-mass spectrometry was used to quantify amodiaquine and its active metabolite, desethylamodiaquine, in plasma samples. A low sample volume of 100 µl, and high-throughput extraction technique using a supported liquid extraction (SLE+) technique on an automated liquid handler platform for faster sample processing are some of the advantages of this method. Separation of amodiaquine from desethylamodiaquine was achieved using a reversed phase Zorbax SB-CN 50 mm × 4.6 mm, I.D. 3.5 µm column with acetonitrile and 20 mM ammonium formate with 1% formic acid pH ~ 2.6 (15–85, v/v) as mobile phase. The absolute recoveries of amodiaquine and desethylamodiaquine were 66% to 76%, and their isotope label internal standard were in the range of 73% to 85%. Validation results of the developed method demonstrated intra-batch and inter-batch precisions within the acceptance criteria range of ± 15.0%. There were no matrix or carry-over effects observed. The lower limit of quantification was 1.08 ng/ml for amodiaquine and 1.41 ng/ml for desethylamodiaquine. The method showed robust and accurate performance with high sensitivity. Thus, the validated method was successfully implemented and applied in the evaluation of a clinical trial where participants received artemether–lumefantrine plus amodiaquine twice daily for three days (amodiaquine dose of 10 mg base/kg/day).

Efficient conversion of straw cellulose to chemicals or fuels is an attracting topic today for the utilization of biomass to substitute for fossil resources. The development of catalysts is of vital importance. In this work, a composite catalyst Metal-organic frameworks (MOFs) immobilized on three-dimensional reduced graphene oxide (3D-rGO) were synthesized by in situ growth of the MIL-101(Cr) within the 3D-rGO matrix. The supporting of 3D-rGO guaranteed the dispersion and acid site density of MIL-101(Cr). The MIL-101(Cr)@3D-rGO nanocomposite possesses excellent catalytic activity, stability, recyclability and is an idea catalyst for the efficient degradation of straw cellulose into formic acid (FA), acetic acid (AA) and oxalic acid (OA). A maximum FA conversion rates of 95.36% was obtained by using MIL-101(Cr)@3D-rGO(1:1) as catalyst and hydrothermal reaction at mild conditions of 200 °C for 1h in alkaline aqueous medium. The MIL-101(Cr)@3D-rGO nanocomposite can be reused with high catalytic activity without any collapse of structure or leaching of chromium.

Improving the transfer hydrogenation of N-heteroarenes is of key importance for various industrial processes and remains a challenge so far. We reported here a microcapsule-pyrolysis strategy to quasi-continuous synthesis S, N co-doped carbon supported Co single atom catalysts (Co/SNC), which was used for transfer hydrogenation of quinoline with formic acid as the hydrogen donor. Given the unique geometric and electronic properties of the Co single atoms, the excellent catalytic activity, selectivity and stability were observed. Benefiting from the quasi-continuous synthesis method, the as-obtained catalysts provide a reference for the large-scale preparation of single atom catalysts without amplification effect. Highly catalytic performances and quasi-continuous preparation process, demonstrating a new and promising approach to rational design of atomically dispersed catalysts with maximum atomic efficiency in industrial.

The reaction of carbon dioxide with hydroxide to form carbonate in near neutral or alkaline medium severely limits the energy and carbon efficiency of CO2 electroreduction. Here we show that by suppressing the otherwise predominant hydrogen evolution using alkali cations, efficient CO2 electroreduction can be conducted in acidic medium, overcoming the carbonate problem. The cation effects are general for three typical catalysts including carbon supported tin oxide, gold, and copper, leading to Faradaic efficiency of as high as 90% for formic acid and CO formation. Our analysis suggests hydrated alkali cations physisorbed on the cathode modify the distribution of electric field in the double layer, which impedes hydrogen evolution by suppress the migration of hydronium ions while at the same time promotes CO2 reduction by stabilizing key intermediates.

Biodiesel was used to prepare epoxidized fatty acid isobutyl esters (Ep-FABEs) as a biobased plasticizer in this work. Transesterification of biodiesel with isobutanol catalyzed by tetrabutyl titanate was carried out in a gas-liquid tower reactor. The conversion achieved nearly 100% within 5 h under the reaction temperature, the mass ratio of catalyst to fatty acid methyl esters (FAMEs), and isobutanol to FAMEs total molar ratio of 180 °C, 0.4 %(mass), and 5.4:1, respectively. In addition, kinetic model of the transesterification reaction was developed at 150–190 °C. The calculated activation energy was 48.93 kJ·mol−1. Then, the epoxidation of obtained fatty acid isobutyl esters (FABEs) was conducted in the presence of formic acid and hydrogen peroxide. The Ep-FABEs was further analyzed for its plasticizing effectiveness to replace dioctyl phthalate (DOP) and compared with conventional epoxy plasticizer epoxidized fatty acid methyl esters (Ep-FAMEs). The results indicated that the thermal stability and mechanical properties of PVC films with Ep-FABEs plasticizer were significantly improved compared with those plasticized with DOP. In addition, the extraction resistance and migration stability of Ep-FABEs were better than those of Ep-FAMEs. Overall, the prepared Ep-FABEs via structural modification of biodiesel proved to be a promising biobased plasticizer.

Formic acid (FA), which can be produced via CO2 reduction and biomass conversion, has received extensive interest as a convenient and safe hydrogen carrier due to its wide range of sources, renewable, high hydrogen content (4.4 wt%), and convenient storage/transportation. Designing highly efficient catalysts is the main challenge to realize the hydrogen production from FA. In this work, well-dispersed and electron-rich PdIr alloy nanoparticles with a size of 1.8 nm are confined in amino-modified 3D mesoporous silica KIT-6 and applied as a highly efficient catalyst for robust hydrogen production from FA at ambient temperature. Small PdIr alloy nanoparticles confined by amino-modified KIT-6 (PdIr/KIT-6-NH2) lead to better catalytic activity compared to that of Pd/KIT-6-NH2 and PdIr confined by bare KIT-6, achieving a high turnover frequency (TOF) value of 3533 h−1 at ambient temperature (303 K), 100% H2 selectivity and conversion toward the dehydrogenation of FA, which is comparable to the best heterogeneous catalysts ever reported. The high catalytic activity of PdIr/KIT-6-NH2 can be attributed to the synergistic effect between Pd and Ir, strong interaction between PdIr and KIT-6-NH2, as well as the amino-groups of KIT-6-NH2 which can act as a proton scavenger to promote the breaking of O-H bond of formic acid.

Formic acid is one of the key components in green chemistry being involved in energy storage, production of chemical intermediates and fuel components. Therefore the knowledge of its stability is of crucial importance and a systematic study of its decomposition is needed. The kinetics of formic acid decomposition to hydrogen and carbon dioxide was investigated in a laboratory-scale fixed bed reactor at 150–225 °C and atmospheric pressure. Palladium nanoparticles deposited on porous active carbon Sibunit were used as the heterogeneous catalyst. The catalyst was characterized by nitrogen physisorption and high-resolution transmission electron microscopy. The average palladium nanoparticle size was 5–6 nm. The impacts of mass transfer resistance and formic acid dimerization were negligible under the reaction conditions. Prolonged experiments revealed that the catalyst had a good stability. Hydrogen and carbon dioxide were the absolutely dominant reaction products, whereas the amounts of carbon monoxide and water were negligible. The experimental data were described with three kinetic models: first order kinetics, two-step adsorption-reaction model and multistep adsorption-decomposition model of formic acid. The multistep model gave the best description of the data.

This study investigated the rapid start-up of partial nitrification through different inhibitor addition, including hydroxylamine (NH2OH), potassium chlorate (KClO3), and formic acid (HCOOH). Then,...

The electrochemical CO2 reduction (ECR) to produce value-added fuels and chemicals using clean energy sources (like solar and wind) is a promising technology to neutralize the carbon cycle and reproduce the fuels. Presently, the ECR has been the most attractive route to produce carbon-building blocks that have growing global production and high market demand. The electrochemical CO2 reduction could be extensively implemented if it produces valuable products at those costs which are financially competitive with the present market prices. Herein, the electrochemical conversion of CO2 obtained from flue gases of a power plant to produce diesel and formic acid using a consistent techno-economic approach is presented. The first scenario analyzed the production of diesel fuel which was formed through Fischer-Tropsch processing of CO (obtained through electroreduction of CO2) and hydrogen, while in the second scenario, direct electrochemical CO2 reduction to formic acid was considered. As per the base case assumptions extracted from the previous outstanding research studies, both processes weren’t competitive with the existing fuel prices, indicating that high electrochemical (EC) cell capital cost was the main limiting component. The diesel fuel production was predicted as the best route for the cost-effective production of fuels under conceivable optimistic case assumptions, and the formic acid was found to be costly in terms of stored energy contents and has a facile production mechanism at those costs which are financially competitive with its bulk market price. In both processes, the liquid product cost was greatly affected by the parameters affecting the EC cell capital expenses, such as cost concerning the electrode area, faradaic efficiency, and current density.

Atmospheric organic acids (OAs) are expected to enhance methanesulfonic acid (MSA)-driven new particle formation (NPF). However, the exact role of OAs in MSA-driven NPF remains unclear. Here, we employed a two-step strategy to probe the role of OAs in MSA–methylamine (MA) NPF. Initially, we evaluated the enhancing potential of 12 commonly detected OAs in ternary MA–MSA–OA cluster formation by considering the formation free energies of the (MSA)1(MA)1(OA)1 clusters and the atmospheric concentrations of the OAs. It was found that formic acid (ForA) has the highest potential to stabilize the MA–MSA clusters. The high enhancing potential of ForA results from its acidity, structural factors such as no intramolecular H bonds, and high atmospheric abundance. The second step is to extend the MSA–MA–ForA system to larger cluster sizes. The results indicate that ForA can indeed enhance MSA–MA NPF at atmospheric conditions (the upper limited temperature is 258.15 K), indicating that ForA might have an important role in MSA-driven NPF. The enhancing effect of ForA is mainly caused by an increased formation of the (MSA)2(MA)1 cluster, which is involved in the pathway of binary MSA–MA nucleation. Hence, our results indicate that OAs might be required to facilitate MSA-driven NPF in the atmosphere.

Photocatalytic NO3– reduction in water has been regarded as a promising route due to its high efficiency and green feature. Several limiting factors, such as lack of catalytic sites, insufficient light collection, and spatial charge separation capacity photocatalytic denitrification, still need to be overcome for the practical applications. Herein, an innovative LiNbO3/ZnS heterojunction with a unilateral opening core–shell structure was constructed. ZnS was tightly anchored on the surface of LiNbO3 by modified electrostatic self-assembly method. High nitrate removal rate (98.84%) and N2 selectivity (98.92%) were achieved with a molar ratio of LiNbO3 and ZnS of 1:5 (1:5L-ZS) using formic acid as a hole scavenge. The LiNbO3/ZnS degradation kinetics of NO3– was corresponding to the first-order kinetics equation. The nitrate removal rate and N2 selectivity remained stable after three cycles in such photocatalytic NO3– reduction. The outstanding photocatalyst performance can be ascribed to the improved surface active sites, the well-matched band structure, and the unique core–shell structure. It provides an effective strategy for controllable fabrication of core–shell photocatalyst with strong light-harvesting ability and charge separation efficiency to enhance the removal rate of nitrate in water.

Pomalidomide is an immunomodulatory agent (IMiD) that has been approved by the US Food and Drug Administration (FDA) for clinical treatment of patients with multiple myeloma. In this work, we developed a sensitive and validated LC-MS/MS method for high-throughput determination of pomalidomide over the range of 1.006–100.6 ng/mL (R2 = 0.9991) in human plasma and pharmacokinetic studies. A liquid-liquid extraction method using ethyl acetate was applied to extract pomalidomide and afatinib (as an internal standard, IS) from human plasma. Chromatographic separation was performed on a Hedera ODS column (150 mm × 2.1 mm, 5 μm) with security guard C18 column (4 mm × 2.0 mm) at 40 °C. Methanol and 10 mmol/L aqueous solution of ammonium acetate containing 0.1% formic acid were used as a gradient elution mobile phase, and the flow rate was 0.4 mL/min. A triple quadruple tandem mass spectrometer using multiplex reaction monitoring mode (MRM) with electrospray ionization (ESI) positive ionization was employed. The precursor to product ion transitions for the quantitative analysis of pomalidomide and the IS were m/z 274.2→163.1 and m/z 486.1→371.1, respectively. This established method has been validated according to regulatory guideline, and the results were all within the acceptance criteria. The validated LC-MS/MS method was successfully applied to analyze samples obtained from clinical pharmacokinetics study after oral administration of pomalidomide (4 mg) capsules in human.

The present work, in which cellulose isolated from formic acid fractionation (FAC) is decorated with polyetherimide (PEI) to attain highly efficient cellulose-derived PdAgbimetallic catalyst (PdAg-PEI-FAC), has been investigated, and the catalyst properties are characterized by XRD, XPS, BET, ICP-AES and HAADF-STEM. The as-obtained Pd3.75Ag3.75-PEI-FAC exhibits excellent catalytic performance for H2 evolution from a sodium formate-free formic acid (FA) aqueous medium at ambient temperature and the turnover frequency (TOF) reaches a high value of 2875 h-1, which is superior to most of the previously reported Pd-based heterogeneous catalysts supported on a carbon matrix in the literature. The remarkable catalytic activities of PdAg-PEI-FAC result from high dispersion Pd and synergistic effects between the PdAg bimetallic system. Furthermore, the amide (-NH) group in PEI coated on cellulose acting as a proton scavenger efficiently improves the catalytic property of catalyst. In addition, the critical factors affecting H2 release, such as FA concentration, reaction temperature, PdAg compositions and support matrix type, are also evaluated. Based on the experimental results, the probable three-step mechanism of H2 evolution from FA over Pd3.75Ag3.75-PEI-FAC is proposed. In the end, the activation energy (Ea) of Pd3.75Ag3.75-PEI-FAC catalyst is calculated to 53.97 kJ/mol, and this catalyst shows unique robustness and satisfactory re-usability with no loss of catalytic activity after five recycles. The findings in this work provide a novel routine from lignocellulose fractionation towards cellulose-derived catalyst for H2 evolution.

Background: Presently worldwide manufacturing of formic acid follows the permutation of methanol and carbon monoxide in presence of a strong base. But due to the use of toxic CO molecule and easy availability of CO2 molecule in the atmosphere, most of the research has been shifted from the conventional method of formic acid synthesis to direct hydrogenation of CO2 gas using different homogenous and heterogeneous catalysts. Objective: To develop reaction protocol to achieve easy CO2 hydrogenation to formic acid using Ionic liquid reaction medium. Methods: We used the sol-gel method followed by calcination (over 250oC for 5 hours) to synthesize two types of ruthenium metal-doped TiO2 nanoparticles (with and without ionic liquids), namely Ru@TiO2@IL and Ru@TiO2. We are reporting the application NR2 (R= CH3) containing imidazolium- based ionic liquids not only to achieve a good reaction rate but also to get agglomeration free ruthenium metal-doped TiO2 nanoparticles along with easy product isolation due to the presence of NR2 (R= CH3) functionality in ionic liquid structure. We synthesized various NR2 (R= CH3) functionalized ionic liquids such as 1-Butyl-3-methylimidazolium Chloride, 1,3-di(N,Ndimethylaminoethyl)- 2-methylimidazolium trifluoromethanesulfonate ([DAMI][TfO]), 1,3-di(N,Ndimethylaminoethyl)- 2-methylimidazolium bis (trifluoromethylsulfonyl) imide ([DAMI][NTf2]) and 1-butyl-3-methylimidazolium chloride ionic liquids which were synthesized as per the reported procedure. Results: We easily developed two types of Ru metal-doped TiO2 nanoparticles using the sol-gel method. After calcination, both Ru@TiO2@IL (3.2 wt% Ru), and Ru@TiO2 (1.7 wt% Ru) materials were characterized by XRD, FTIR, TEM, ICP-AES, EDS, and XANES analysis. After understanding the correct structural arrangement of Ru metal over TiO2 support, we utilized both Ru@TiO2@IL (3.2 wt% Ru) and Ru@TiO2 (1.7 wt% Ru) the materials as a catalyst for direct hydrogenation of CO2 in the presence of water and functionalized [DAMI] [TfO] ionic liquid. Conclusion: Here we demonstrated the preparation and characterization of TiO2 supported Ru nanoparticles with and without ionic liquid. After understanding the correct morphology and physiochemical analysis of Ru@TiO2@IL (3.2 wt% Ru), and Ru@TiO2 (1.7 wt% Ru) catalysts, we examined their application in CO2 reduction and formic acid synthesis. During the optimization, we also noticed the significant effect of functionalized [DAMI] [TfO] ionic liquid and water to improve the formic acid yield. Lastly, we also checked the stability of the catalyst by recycling the same till the 7th run.

Inefficient electrocatalysts and high-power consumption are two thorny problems for electrochemical hydrogen (H2) production from acidic water electrolysis. Herein we report the one-pot precise synthesis of ultrafine Au core-PtAu alloy shell nanowires (Au@PtxAu UFNWs). Among them, Au@Pt0.077Au UFNWs exhibit the best performance for formic acid oxidation reaction (FAOR) and hydrogen evolution reaction (HER), which only require applied potentials of 0.29 V and −22.6 mV to achieve a current density of 10 mA cm−2, respectively. The corresponding formic acid electrolyzer realizes the electrochemical H2 production at a voltage of only 0.51 V with 10 mA cm−2 current density. Density functional theory (DFT) calculations reveal that the Au-riched PtAu alloy structure can facilitates the direct oxidation pathway of FAOR and consequently elevates the FAOR activity of Au@Pt0.077Au UFNWs. This work provides meaningful insights into the electrochemical H2 production from both the construction of advanced bifunctional electrocatalysts and the replacement of OER.

Biohydrogen (H 2 ) production has the potential to provide clean, environmentally friendly, and cost-effective energy sources. The effect of increasing oxidative stress on biohydrogen production by acid-treated anaerobic digestion microbial communities was studied. The use of varying amounts of hydrogen peroxide (H 2 O 2 ; 0.1, 0.2, and 0.4 mM) for enhancing hydrogen production from melon fruit waste was investigated. It was found that H 2 O 2 amendment to the H 2 -producing mixed culture increased hydrogen production. Treatment with 0.4 mM H 2 O 2 increased cumulative H 2 output by 7.7% (954.6 mL/L), whereas treatment with 0.1 mM H 2 O 2 enhanced H 2 yield by 23.8% (228.2 mL/gVS) compared to the untreated control. All treatments showed a high H 2 production rate when the pH was 4.5 – 7.0. H 2 O 2 -treated samples exhibited greater resilience to pH reduction and maintained their H 2 production rate as the system became more acidic during H 2 fermentation. The application of H 2 O 2 affected the volatile fatty acid (VFA) profile during biohydrogen fermentation, with an increase in acetic and propionic acid and a reduction in formic acid concentration. The H 2 O 2 treatment positively affects H 2 production and is proposed as an alternative way of improving H 2 fermentation.

The photocatalytic degradation of ethylene over TiO2 has been widely studied, however, there are discrepancies between the degradation mechanisms proposed in experimental works. Some of them propose a degradation and mineralization mechanism trough ethoxide, acetaldehyde, acetic acid and finally carbon dioxide, whereas others did not find acetaldehyde or acetic acid, but formaldehyde and formic acid as intermediaries in the same process through the presence of the formyl radical HCOO on the catalyst surface. Through ab initio calculations it is possible to analyze the published experimental mechanisms in order to theoretically assess their feasibility and establish the possible reaction intermediaries and generated products. In this work, we used the Density Functional Theory based method DFT-RPBE/ 6-31G** in order to determine energy values to then estimate the enthalpy changes associated with each of the stages proposed for the ethylene degradation and mineralization processes, with which we elucidated the thermodynamically most probable mechanism, which explains differences between experimental work reports. We found that the most favorable route is through the formation of acetic acid, however, only one of the carbon atoms is converted to CO2, the other one is also converted to CO2 but from the formaldehyde degradation. These results agree with and explain those reported from experimental works. The method we used was validated by obtaining deviations shorter than 5% when comparing bond lengths, bond angles, dihedral angles, and vibrational frequencies calculated in this work versus experimental published values for most of the molecules involved.

High-performance polymeric membrane technology is rapidly developing worldwide with the introduction of new materials and processes. Considerable research efforts are being made to establish a polymer membrane that can be used for ultrafiltration (UF) or nanofiltration (NF) applications. The development of modified polyamide-66 polymer and its compatibility in wastewater are essential elements in the quest for advances and improvements in membrane technology. The optimized conditions for membrane synthesis are critical in making it commercially viable. Response Surface Methodology (RSM) was used to find the optimum dissolution of polyamide-66 in formic acid. A model was developed and validated with experimental data, and it showed good agreement with R2 0.9984. The optimized condition for minimizing viscosity was determined. For minimum viscosity (3.64 cp), the optimum temperature and wt.% were 20 ?C and 0.6, respectively.

CO2 is one of the leading greenhouse gases, so studies that turn this gas into higher value-added products, that function as simpler and cheaper hydrogen stores, as an alcohols, are extremely important. In this work we using a polymeric Electrolyte Reactor– fuel cell type supplied with H2 on platinum anode and dry CO2 in the cathode with a copper-carbon electrocatalyst. Copper nanoparticles supported on carbon Vulcan XC72 were produced by the sodium borohydride reduction method. The XRD revealed the presence of two different phases, CuO and Cu2O. In addition, the TEM images revealed agglomerates presence. The water, formaldehyde, methanol, methane, formic acid, dimethyl ether, oxalic acid, dimethyl carbonate, and ethylene-glycol were observed by differential mass spectroscopy on line with the reaction and the onset potential for each product and these results were confirmed by infrared spectroscopy – ATR-FTIR setup. This work showed the mapping CO2 reduced compounds for onset potential proposing some contributions to the literature.

Low-cost non-noble metal catalyst for dehydrogenation of formic acid to hydrogen at near room temperature is considered as a key to promoting commercial technology for clean energy. We have constructed reduced graphene oxide (RGO) self-assembly bonded nickel particles for synthesis of graphene nanosheets embedded with nickel nanoparticles architecture Ni@xRGO. Nitrogen and oxygen co-doped graphene facilitates the adsorption of hydrogen protons from formic acid. Electron transfer ability of Ni@xRGO with active sites is enhanced via Ni–C bond in the interface between the RGO nanosheets and nickel particles, which promoted the C–H bond breaking for dehydrogenation of formic acid. The Ni@0.20RGO has excellent catalytic performance for hydrogen production from formic acid at near room temperature (the yield of hydrogen, 240.0 mL g−1 h−1 at 50 °C), comparable to the most active non-noble metal catalysts.

In this study, the epoxidized palm oil was synthesized with hydrogen peroxide (H2O2) as an oxygen donor and formic acid as an oxygen carrier. The effect of H2O2 concentration on the chemical structure and thermal properties of epoxidized palm oil was investigated. The FT-IR results showed the disappearance of unsaturated double bonds together with the formation of oxirane groups. The excess concentration of H2O2 caused an undesirable reaction that the oxirane ring was diminished. DSC results showed that the Tm and Tc of epoxidized palm oil were shifted toward higher values. The epoxidation of palm oil can be utilized as a reactant for bio-based epoxy resins, which improve local resource value-added palm oil in Thailand.

MnOx catalysts were synthesized under hydrothermal conditions for converting glucose to formic acid (FA) in water with the objective to develop vanadium-free reaction systems. An FA yield of 81.1% was obtained with MnOx catalyst and glucose substrate in water at 160 oC, which is almost twice the value of that obtained with vanadium-based heterogeneous catalysts. MnOx materials prepared hydrothermally at 100 oC had higher Mn2+/ Mn3+ ratios and adsorbed oxygen species than those prepared at higher temperatures and gave the highest FA yields among catalysts evaluated. Mechanistic studies of glucose-MnOx-water reaction systems revealed that two parallel reactions exist with arabinose being intermediate in the α-scission route and glyoxylic acid being intermediate in the β-scission route where CO2 co-forms with FA. Small water-soluble carbohydrates (glucose, sucrose, cellobiose, maltose, xylose) afforded FA yields greater than 50%, while starch afforded >20% FA yields, thus demonstrating potential of MnOx for converting biomass into FA.

A peerless inexpensive electrochemical engineering of spherical Pt nanoparticles (nano-Pt: ca. 100 nm in average diameter) was achieved with intersected ferric oxyhydroxide nanotubes (α-FeOOH (goethite): ca. 20 nm in average diameter). The FeOOH@Pt catalyst exhibited ca. 2.5 and 1.94-times increases in the catalytic activity and poisoning tolerance, respectively, of the formic acid electro−oxidation (FAO) – the anodic reaction in the direct formic acid fuel cells (DFAFCs). Surprisingly, with a post-activation of the FeOOH@Pt catalyst at 0.48 V vs. reversible hydrogen electrode (RHE) in 0.2 mol L−1 NaOH, a favorable Fe2+/Fe3+ transformation succeeded to eliminate the permanent CO poisoning of Pt that impaired the catalytic performance of DFAFCs. This was synchronized (relatively to nano-Pt) with a four-fold increase in the catalytic efficiency, ca. −174 mV shift in the onset potential, and eightfold enhancement in the catalyst's durability for FAO. The activated FeOOH@Pt catalyst also showed a mass activity of 296 mA mg−1Pt (at 0.8 V), which was ca. nine times higher than that (34 mA mg−1Pt) of the commercial Pt/C catalyst. The ascertained improvement in the electron transfer at the FeOOH@Pt surface foresees quick industrialization for DFAFCs.

We present an operationally simple redox coupling for the synthesis of N-1 substituted benzimidazole using feedstock building block 2-nitroaniline derivatives as the precursors and methanol as the C1 source. Higher atom, step, and redox economy and excellent regioselectivity were achieved compared with the conventional synthesis using diaminobenzene and formic acid derivatives.

Photoelectrochemical CO2 reduction by Cu2ZnSnS4 (CZTS) photocathodes is a potentially low-cost and high-efficiency CO2 conversion approach. However, the current CZTS-based photocathodes for the CO2 reduction reaction (CO2RR) are challenged by the active side reaction of the hydrogen evolution reaction (HER) and the incompatibility with efficient electrocatalysts. In this work, by means of density functional theory (DFT), we predict that a (220)-facet-suppressed kesterite CZTS could be an efficient photo-electro-integrated photocathode for formic acid production in the CO2RR. The results show that the competitive HER is mostly favored on the (220) facet. And the CO2RR for formic acid production on the (112) and (312) facets exhibits a thermodynamic energy barrier lower than 0.26 eV. Different from the d-band theory in metal electrocatalysts, it is found that the density of low energy unoccupied states in the S 3p orbital plays a key role in determining the CO2RR reaction path of the kesterite CZTS. Furthermore, two different trends of adsorption energy depending on the chemical characteristic of adsorbates are analyzed. Our study unveils the potential for selectively reducing CO2 into formic acid with kesterite CZTS and provides a possible route for manipulating the electrocatalytic properties of metal sulfide catalysts.

The main objective was to develop a wipe sampling test to measure surface contamination of the most frequently used antineoplastic drugs (ADs) in Swedish healthcare and furthermore to develop an analysis method sensitive enough to assess low levels of contamination. Two wipe sampling tests with separate sample processing methods assessing i) cyclophosphamide (CP), ifosfamide (IF), 5-fluorouracil (5-FU), etoposide (ETO), gemcitabine (GEM) and cytarabine (CYT) (Wipe Test 1), and ii) GEM, CYT and methotrexate (MTX) (Wipe Test 2), respectively were developed by optimization of absorption and extraction efficiencies using different wipe tissue materials, tissue wetting solution and extraction solvents. A fast LC-MS/MS method was developed for simultaneous detection of the studied ADs. The limit of quantification for the method was between 0.04 to 2.4 ng/wipe sample (0.10 to 6.1 pg/cm2 for an area of 400 cm2) and at 50 ng/sample the within-day precision was between 1.3-15%, and the accuracy between 102-127%. Wipe Test 1 was applied in an assessment of cleaning efficiency of five different cleaning solutions (formic acid, water, sodium hydroxide, ethanol and sodium dodecyl sulfate (SDS) for removal of ADs from surfaces made of stainless steel or plastic. For CP, IF, 5-FU, GEM and CYT 92% of the AD were removed regardless of surface and cleaning solution. In conclusion, a user-friendly assessment method to measure low levels of seven ADs in the work environment was developed and validated. Assessment of the decontamination efficiency of cleaning solutions concerning removal of ADs from stainless steel showed that efficiencies differed depending on the AD with water being the least effective cleaning agent. The results suggests that a combination of different cleaning agents including detergent and a solution with an organic component would be optimal to efficiently remove the measured ADs from surfaces in the workplace.

Bismuth oxyhalides (BiOX, X = F, Cl, Br, I) are emerging energy materials because of their remarkable catalytic activity. The BiOX compounds usually have a tetragonal type crystal structure with unique layered morphology consisting of [X-Bi-O-Bi-X] sheets. Although the BiOX nanosheets exposed with {001} facets perform superior photoactivity, there is lack of understanding about their capability in the electrochemical CO2 reduction reaction (CO2RR). Herein, we adopt wet-chemical syntheses to make 2D BiOCl and Pd-doped BiOCl nanosheets for CO2RR. In the results, formic acid is the only one kind of product converted from CO2 along with H2 gas from water reduction over both BiOCl and Pd-doped BiOCl nanosheets. By thorough analyses with ex situ and in situ spectroscopy, the results reflect that (1) metallic Bi0 atoms generated by the applied negative potentials serve as the catalytic sites for the hydrogen evolution reaction (HER) and CO2RR and (2) the existence of doped Pd ions in the BiOCl structure reduces the barrier of charge transfer over the nanosheets, which enhances HER and CO2RR activities. We believe that the observations are important references for making catalysts toward CO2RR performance.

C3 -alcohols can theoretically provide high current efficiencies in direct fuel cell applications because of their intrinsically large energy densities. However, during realistic reactions, molecular multiple carbon–carbon (C C C) bonds are hardly broken, severely reducing current efficiencies. Herein, directly with commercial Pt/C as the catalyst, the operation of co-fueling with formic acid significantly enhances the current efficiencies of two types of C 3-alcohols, namely, isopropanol and 1,2-propanediol. Compared with the current densities of pure C3-alcohols, those of co-fueled C3-alcohols increase maximally by 9.9 times. The reason lies in the fact that the co-fueling design facilitates the breaking of C C C bonds, as elucidated by charge distributions that are obtained via electrochemical nuclear magnetic resonance analyses. Density-functional-theory computational results indicate that the generation of OH groups adsorbed on Pt surfaces is promoted in co-fueling experiments, reducing energy barriers for breaking progress. The co-fueling strategy is capable of optimizing C3-alcohol electrooxidations in direct fuel cells and deserves extensive study.

The selective oxidation of methanol to methyl formate is one of the most attractive processes to obtain value-added methanol-downstream products. The development of highly efficient and stable catalysts is critical for this transformation. In this study, a series of MIL-88B(Fex,Co1–x) bimetallic catalysts with different Fe/Co molar ratios were prepared through a one-pot hydrothermal method. X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, energy dispersive spectroscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, N2 adsorption-desorption, and inductively coupled plasma-mass spectrometry characterization were performed to elucidate the structure of the catalysts. The activity of the catalysts were assessed in the one-step oxidation of methanol to methyl formate with H2O2 in a liquid-phase batch reactor. The results show that the MIL-88B(Fex,Co1–x) catalysts exhibit uniform needle-like morphologies with an average length and width of 400–600 nm and 100–150 nm, respectively. Co2+ is incorporated into the framework by partially replacing Fe3+ in MIL-88B. Moreover, the catalyst efficiently promoted the conversion of methanol to methyl formate. When MIL-88B(Fe0.7,Co0.3) catalyst was used with a molar ratio of H2O2 to methanol of 0.5 at 80 °C for 60 min, 34.8% methanol conversion was achieved, and the selectivity toward methyl formate was 67.6%. The catalysts also showed great stability with a steady conversion and selectivity even after four cycles. The preliminary oxidation mechanism was also studied. It was determined that H2O2 is first adsorbed on the Fe3+ sites and subsequently activates these sites. Methanol is adsorbed by the O atoms of the framework through hydrogen bonding and is gradually oxidized to formic acid. Subsequently, formic acid reacts with the residual methanol at the Fe3+ and Co2+ Lewis acid sites to form methyl formate.

Carbon dioxide (CO2) assisted synthesis of water-soluble silver nanoparticle with a narrow particle size distribution is reported here based on the phase-inversion procedure. Bio-derived chitosan (CS) is used to stabilize the metal nanoparticles according to its abundant functional groups. Formic acid is employed as both a solvent (for the polymer) and a reductant for in-situ reducing the silver precursor along with the solvent evaporation. CO2 is utilized to combine with the amino groups of CS, reducing the viscosity of chitosan/formic acid solution and limiting the formation of hydrogen bonds. This promotes the stabilization and reduction efficiency of silver nanoparticles. In particular, 100% of Ag metal nanoparticles with the size of 7.5 ± 2.3 nm is successfully synthesized with the assistance of CO2. Interestingly, the synthesized CS/Ag nanocomposites are water-soluble owing to the formation of carbamate groups. This water-soluble silver nanoparticle presents an exceptional performance in the selective reduction of 4-nitrophenol, where the turnover frequency (TOF = 599 h−1) is even double with respect to the CO2 free system.

The increase of harmful carbon monoxide (CO) caused by incomplete combustion can affect human health even lead to suffocation. Therefore reducing the CO discharged by vehicles or factories is urgent to improve the air quality. The spinel cobalt (II, III) oxide (Co3O4) is an active catalyst for CO abatement. In this study, we tried to fabricate dispersing Co3O4 via the dispersion-precipitation method with acetic acid, formic acid, and oxalic acid as the chelating dispersants. Then, the asprepared samples were calcined at 300 ºC for 4 h to obtain active catalysts, and assigned as Co(A), Co(F) and Co(O) respectively, the amount of the dispersants used are labeled as I (0.12 mole), II (0.03 mole) and III (0.01 mole). For comparison, another CoAP sample was prepared via alkaliinduced precipitation and calcined at 300 ºC. All samples were characterized by X-ray diffraction (XRD), temperature-programmed reduction (TPR), scanning electron microscope (SEM), and nitrogen adsorption/desorption system, and the catalytic activity focused on the CO oxidation. The influence of chelating dispersant on the performance of abatement of CO was pursued in this study. Apparently, the results showed that the chelating dispersant can influence the catalytic activity of CO abatement. An optimized ratio of dispersant can improve the performance, while excess dispersant lessens the surface area and catalytic performance. The series of Co(O) samples can easily donate the active oxygen since the labile Co–O bonding and indicated the preferential performance than both Co(A) and Co(F) samples. The nanorod Co(O)-II showed preferential for CO oxidation, T50 and T90 approached 96 and 127 ºC, respectively. Also, the favorable durability of Co(O)-II sample maintains 95% conversion still for 50 h at 130 ºC and does not emerge deactivation.

Carbamate pesticides are a class of synthetic pesticides having wide antimicrobial spectrum, good insecticidal efficacy, and a short residual period. These pesticides are used in agriculture, forestry, and animal husbandry. Their widespread use in the last two decades has led to the existence of drug residues in the environment, which are transferred to food, thereby raising concerns regarding the potential threat to human health. Rapid and accurate detection of carbamate pesticide residues in food is of great significance for food safety, and this requires pretreatment to purify the target components and maximize the accuracy and precision of the analysis. A rapid and accurate analytical method based on online solid phase extraction/purification-high performance liquid chromatography-tandem mass spectrometry (online SPE-HPLC-MS/MS) was established for the determination of eight carbamate pesticides in tomato, rice, and cabbage. About 5.0 g of tomato (without water), 2.0 g of cabbage, and 2.0 g of rice (mixed with 3 mL of water) were vortexed at 1000 r/min for 1 min. After adding 2 g of sodium chloride and 10 mL of acetonitrile containing 0.5% (v/v) formic acid, the samples were extracted and centrifuged. The supernatants were combined after the samples were extracted again. The reconstituted solutions were then purified on a CAPCELL PAK C18 column (50 mm×2.0 mm, 15 μm). When the volume ratio of 0.1% (v/v) formic acid aqueous solution and acetonitrile (used as the mobile phases) was 90∶10 and 35∶65, the eight carbamate pesticides could be completely adsorbed and eluted. The carbamate pesticides were separated on an ACQUITY UPLC CSH C18 column (100 mm×2.1 mm, 1.7 μm) under gradient elution and analyzed in the multiple reaction monitoring (MRM) mode with positive electrospray ionization (ESI+). Under the optimum conditions, the calibration curves of the eight carbamate pesticide residues showed good linearity (r>0.995) within their respective linear ranges. The limits of quantification (LOQs) and limits of detection (LODs) were in the range of 0.05-1.0 ng/mL (S/N=10) and 0.01-0.3 ng/mL (S/N=3). The recoveries were in the range of 73.76%-112.32% at three spiked levels (2, 10, and 20 ng/mL), with relative standard deviations of 1.28%-13.14% (n=6). The online purification method showed better enrichment and purification ability for the target substances than did the offline purification method and greatly improved the pretreatment efficiency. The loading and purification could be completed within 12 min. The developed method has the advantages of high recovery rate, good reproducibility, accuracy, rapidness, sensitivity, and environment friendliness. It can be used for the determination of the eight carbamate pesticides in plant foods, such as tomato, rice, and cabbage.

Formic acid is a promising hydrogen source and liquid organic hydrogen carrier because of its high hydrogen density. To produce hydrogen from formic acid, catalytic dehydrogenation of formic acid over Pd-based catalysts has been investigated. Here, a highly active catalyst is rationally designed. Carbon nanotubes without micropores were adopted as a support to facilitate the mass transport of reactants or products. Pd particles were made as small as possible to provide a large number of active sites and to alleviate the activation barrier for hydrogen desorption. Amine functional groups were introduced into carbon nanotubes to generate formate anions by capturing protons from formic acid. Based on this design, ultrafine Pd nanoparticles (1.76 nm) on amine-functionalized carbon nanotubes were successfully synthesized. This catalyst demonstrated remarkable activity for the formic acid dehydrogenation reaction, with a high turnover frequency value of 2560 h−1 at 30 °C.

Background: Transfer hydrogenation methods that employ non-H2 hydrogen sources have evolved as an attractive alternative for conventional hydrogenation approaches. Objective: In this study, we aimed at developing optimized conditions to induce the selective transfer hydrogenation reduction of aromatic alkynes catalyzed by PdCl2(PPh3)2 and using formic acid as the hydride source. Methods: The effect of various reaction parameters, such as the nature and amount of the catalyst, the H-donor/base couple, reaction time and temperature, and the nature of the solvent on the outcome of the alkyne reduction were investigated. Results: The reduction of the alkyne can be chemoselectively controlled by adjusting the reaction conditions. Among the tested catalysts, PdCl2(PPh3)2 was the most suitable, with 2% of the catalyst being the optimal amount. While the reduction was successful in different solvents of different polarities, THF was selected as the solvent of choice. The reduction of diphenylacetylene yielded the alkene both at 50°C and 80°C. When testing the optimized conditions on the reduction of 4- phenyl-3-butyne-2-one, quantitative partial reduction to the corresponding α,β-unsaturated ketone was obtained at 50°C, while the saturated ketone was produced as the major product at 80°C. Conclusion: The chemoselective reduction of aromatic alkynes was performed successfully with complete conversion using 2% PdCl2(PPh3)2 as a catalyst, formic acid/NEt3 as the H-donor/base couple, THF as the solvent, at 50°C and 80°C.

Electrodeposited composite film electrodes prepared from electroplating baths with varying ratios of Ag+ and Sn2+ triflates were studied to understand how the performance of such materials varies a...

In this study, earth-abundant manganese oxide (MnO2) was used as a catalyst for the electrocatalytic glycerol oxidation with a satisfactory yield and high selectivity under mild pH media; that is, the high current density of 6.0 mA cm−2 and selectivity of ca. 46% for dihydroxyacetone (DHA). MnO2 also exhibited reasonable durability without considerable changes for 3 h. More importantly, by combination of operando Raman and electrochemical studies, a tentative reaction pathway was also proposed. It is found that high selectivity of formic acid at low potential was due to predominant coverage of α-MnO2 on catalyst surface. Meanwhile, at high applied potential, partial transformation of α-MnO2 to δ-MnO2 causes decreasing C-C bond cleavage, leading to high DHA selectivity. The results of this work not only demonstrate that MnO2 holds promise as an efficient electrocatalyst for selectively producing DHA but also provides realistic details on electrochemically generated species under working condition.

A simple, selective and rapid ultra performance liquid chromatography-tandem mass spectrometry method was developed and validated for the simultaneous estimation of dolutegravir, lamivudine and tenofovir in bulk and tablet dosage form. Chromatographic separation was attained on Acquity Ethylene Bridged Hybrid (BEH) C18 column (50 × 2.1 mm, 3.5 µm), using a mixture of acetonitrile and 0.1% formic acid in water (60:40, v/v) as a mobile phase at a flow rate of 0.12 mL/min. The total run time of analysis was 3.5 min. The analytes were detected using tandem mass spectrometry, operating in positive ionization and multiple reaction monitoring modes. The method's linearity was determined to be in the range of 10–150 ng/mL with r2 > 0.99. The proposed method was validated as per the International Council for Harmonization (ICH) guidelines, and the results were found well within the acceptance limits. The method was successfully applied for the simultaneous quantification of all the three analytes in the combined tablet dosage form.

In this work, palladium nanoparticles were deposited on oxygen and phosphorous functionalised carbon nanofibers (CNFs) by sol immobilisation method in order to investigate the support-metal effect on the formic acid (FA) decomposition reaction. In order to establish the presence of functional groups in the support and their effect on Pd nanoparticles, the obtained samples were then, characterised by Transmission Electron Microscopy (HR-TEM, STEM-HAADF and STEM-EDS) and X-ray photoelectron spectroscopy (XPS). FA catalytic decomposition performance, the stability and selectivity of the catalysts were evaluated in liquid-phase at mild reaction conditions. The effect of the metal-support interaction in the reactivity and stability of the catalysts was demonstrated leading to superior catalytic properties in both the functionalised materials. Density functional theory (DFT) simulations provided further insights in the interaction of Pd15 cluster with different support surfaces, i.e. pristine graphene (PG), carboxyl doped graphene (G_COOH), hydroxyl doped graphene (G_OH), carbonyl doped graphene (G_CO) and phosphate doped graphene (G_PO3H). The cluster-support interaction strength follows the trend Pd/G_CO > Pd/G_COOH > Pd/G_OH > Pd/G_PO3H > Pd/PG, confirming the increased stability of 1 wt% Pd@O-HHT and 1 wt% Pd@P-HHT observed in the experimental results.

In recent years, the conversion of biomass-derived platform compounds into a variety of high value fuel and chemical products has attracted increasing attention from researchers. 5-Hydroxymethylfurfural (HMF) and furfural (FFR) belong to a class of important biomass-derived platform chemicals. The molecular structure of HMF and FFR is consisted of aldehyde group, furan ring and other functional groups, which endow them with unique chemical properties. In this paper, the research advances on the catalytic hydrogenation of HMF and FFR in various hydrogen sources, such as hydrogen, alcohol, silanes and formic acid, have been reviewed in detail. In addition, the main influencing factors like catalyst type and reaction conditions on the hydrogenation process as well as the reaction mechanism are discussed in depth. Meanwhile, research foreground in the catalytic hydrogenation of HMF/FFR has been prospected.

An extremely sensitive methodology for the determination of Ru was developed by coupling photochemical vapor generation (PVG) analyte introduction with inductively coupled plasma mass spectrometry (ICPMS). PVG was undertaken with a thin-film flow-through photoreactor in a medium comprising 8 M formic acid in the presence of 10 mg L⁻¹ Co²⁺ and 25 mg L⁻¹ Cd²⁺. The volatile product (presumably ruthenium pentacarbonyl) was generated in a flow injection mode, yielding an overall efficiency of 29% at a sample flow rate of 1.4 mL min⁻¹. The presence of both Co²⁺ and Cd²⁺ sensitizers enhanced PVG efficiency by 3,200-fold, permitting a 31 s irradiation time. Although enhanced efficiency (≈40%) could be obtained with increased Co²⁺ concentration, this was not suitable for routine use due to co-generation of cobalt carbonyl. Excellent repeatability (

A novel mononuclear ruthenium (Ru) complex bearing a PNNP-type tetradentate ligand is introduced here as a self-photosensitized catalyst for the reduction of carbon dioxide (CO2). When the pre-activation of the Ru complex by reaction with a base was carried out, an induction period of catalyst almost disappeared and the catalyst turnover numbers (TONs) over a reaction time of 144 h reached 307 and 489 for carbon monoxide (CO) and for formic acid (HCO2H), respectively. The complex has a long lifespan as a dual photosensitizer and reduction catalyst, due to the sterically bulky and structurally robust (PNNP)Ru framework. Isotope-labeling experiments under 13CO2 atmosphere indicate that CO and HCO2H were both produced from CO2.

Dimethyl sulfoxide (DMSO) is a good solvent as well as a mild oxidizing agent. Several severe incidents associated with DMSO decomposition have been reported in spite of its wide use. The goal of t...

Portable infusion pumps are an interesting solution to continue outpatient parenteral antimicrobial therapy (OPAT) at the patient's home. However, the use of ceftazidime for such applications is challenging in view of its relatively poor stability in solution. In this study, elastomeric infusion pumps with 6 or 7 g of ceftazidime were deflated over 24 h in an oven at 33°C while ceftazidime and its degradation product, pyridine, were regularly monitored. Hereto, a fast and sensitive liquid chromatographic (LC) method has been developed using a Kinetex® C18 (150 × 3 mm, 2.6 μm) column with gradient elution. Ammonium formate 20 mM and acetonitrile (ACN) were mixed in a ratio of 98:2 v/v for mobile phase A and 85:15 v/v for mobile phase B. Both were adjusted to pH 4.5 with formic acid. The flow rate was set at 0.4 mL/min. The solution with a starting dose of 6 g ceftazidime was found to be degraded 10% after an average of 19 h 11 min so that an administration of 6 g to the patient was not reached. For the solution with a starting dose of 7 g of ceftazidime, 10% degradation was observed after an average of 18 h 42 min. However, by starting from a higher dose, an average of 6.56 g of ceftazidime could be administered over 24 h. In addition, 1.0% of pyridine versus ceftazidime pentahydrate with sodium carbonate (=mixture for injection) was formed over 24 h.