Reaction Products Research Articles

Operando electron spin probes for the study of battery processes

Operando electron spin probes, namely magnetometry and electron paramagnetic resonance (EPR), provide real-time insights into the electrochemical processes occurring in battery materials and devices. In this work, we describe the design criteria and outline the development of operando magnetometry and EPR electrochemical cells. Notably, we show that a clamping mechanism, or springs, are needed to achieve sufficient compression of the battery stack and an electrochemical performance on par with that of a standard Swagelok-type cell. The tandem use of operando EPR and magnetometry allows us to identify five distinct and reversible redox processes taking place on charge and discharge of the intercalation-type LiNi0.5Mn0.5O2 Li-ion cathode. While redox processes in conversion-type electrodes are notoriously difficult to investigate using standard characterization methods (e.g. X-ray based) and/or post mortem analysis, due to the formation of poorly crystalline and metastable reaction intermediates and products during cycling, we show that operando magnetometry provides unique insight into the kinetics and reversibility of Fe nanoparticle formation in the Na3FeF6 electrode for Na-based batteries. Step increases in the cell magnetization upon extended cycling indicate the build-up of Fe nanoparticles in the system, hinting at only partially reversible charge–discharge processes. The broad applicability of the tools developed herein to a range of electrode chemistries and structures, from intercalation to conversion electrodes, and from crystalline to amorphous systems, makes them particularly promising for the development of electrochemical energy storage technologies and beyond.

Research on the method of improving carbon storage capacity of a new low calcium CO2 storage binder: Based on the recycling of heavy metal Ba ions

The novel low calcium CO2 storage binder (LCCSB) containing α-CS, C3S2 and C2AS as the primary minerals shows promise as a carbon fixation material, but exhibits low carbonation activity. This study aims to enhance the carbonation activity of LCCSB through barium (Ba) doping, investigate the impact of Ba doping on its carbonation behavior, and elucidate its mechanism. Density functional theory (DFT) simulation, scanning electron microscope test and X-ray diffraction results indicate that Ba ions preferentially substitute Ca atoms within α-CS, followed by Ca sites in C3S2, with a maximum solid solubility of 1mol%. Following Ba ion solid solution into LCCSB, there is an increase in carbonation reaction products along with elevated levels of calcite and aragonite. Additionally, small particles are formed to fill mineral matrix and pores leading to increased porosity and enhanced hardening strength. DFT calculations reveal that Ba ion doping reduces the total bond sequence density TBOD of the LCCSB system while weakening the bond strength of Ca–O bonds thereby accelerating the dissolution of Ca ions. Furthermore, average bond length, volume and distortion index of Ca–O polyhedra increase after Ba ion doping indicating structural distortion resulting in more active sites for potential high carbonation reactivity. This study presents a new research approach for achieving high carbonation activity in LCCSB preparation while also offering insights into the potential for clarifying the carbonation mechanism based on ion-doped LCCSB which could lead to improved environmental and economic benefits for CO2 storage within the cement industry.

Glucose Oxidase-Based Glucose Biosensing with a Simple Dual Ag/AgCl Probe Conductivity Readout.

We describe a conductometric assay of the enzymatic conversion of glucose to gluconic acid by dissolved glucose oxidase (GOx), using the generation of proton and gluconate from the reaction product dissociation for glucose detection. Simple basics of ionic conductivity, a silver/silver chloride wire pair, and a small applied potential translate glucose-dependent GOx activity into a scalable cell current. Enzyme immobilization and complex sensor design, involving extra nanomaterials or microfabrication of electrode structures, are entirely avoided, in contrast to all modern electrochemical glucose biosensors. Assay calibration showed a response linearity up to 500 μM, with a sensitivity of about 1.3 nA/μM. Selectivity tests excluded signals from sugars other than glucose, and glucose quantifications with recovery rates close to 100% were reached with a model sample and a beverage. Easy use of elementary physicochemical phenomena and a satisfactory performance are assets of the proposed non-amperometric glucose biosensing strategy. Assay integration into a planar dual electrode platform, with or without microfluidic application option, is feasible because of the simplicity of the sensor readout and suggests a route to affordable glucose analysis in beverage, food, and body fluid samples.

Spatial distribution of antioxidant activity in baguette and its modulation of proinflammatory cytokines in RAW264.7 macrophages

Baguette is a globally acclaimed bakery staple, composed by a crispy crust and soft crumb, both containing Maillard reaction products (MRPs) with potential bioactivities. However, MRPs’ impacts on the nutritional and health attributes of baguette, particularly in terms of cellular and biological functions, are yet to be clearly elucidated. This study chemically characterizes the crust and crumb of baguettes and investigates the influence of the Maillard reaction on baguette’s nutritional profile, especially in the antioxidant and anti-inflammatory effects. The findings indicate an increase in browning intensity and advanced glycation end products (AGEs) from the baguette’s interior to its exterior, alongside a significant rise in the antioxidant capacity of the crust, suggesting the Maillard reaction’s role in boosting antioxidative properties. Both the crust and crumb demonstrated strong cytocompatibility with immune cells, capable of reducing cellular oxidative stress and regulating intracellular free radical levels. The crust effectively countered peroxyl radical-induced cell membrane hyperpolarization by 91% and completely neutralized the suppression of oxygen respiration in mitochondria, displaying higher efficacy than the crumb. In contrast, crumb extracts were more potent in inhibiting lipopolysaccharide-induced expression of proinflammatory cytokines, such as interleukins-1β (IL-1β) and IL-6, in macrophages. It could provide the fundamental data and cell-based approach for investigating the biological impacts of bread on immune responses, contributing to the refinement and supplementation of nutritional recommendations.

Influence of vacuum and high-temperature on the evolution of mechanical strength and microstructure of alkali-activated lunar regolith simulant

Alkali-activated lunar regolith (AALR) has become one of the most promising lunar building materials, offering the potential to support the construction of large-scale lunar structures. This paper presents a comprehensive experimental investigation on the fresh properties, physical properties, mechanical performance and microstructural characteristics of alkali-activated lunar regolith simulant (AALRS) considering the effects of lunar environments (high-temperature, vacuum and coupled high-temperature and vacuum), alkaline activators (sodium hydroxide and sodium silicate) and curing age. The results show that AALRS under high-temperature environment exhibits higher strength while the strength development is limited. However, AALRS under vacuum environment exhibits lower strength but the strength increases as the curing time increases. In terms of pore structure, the volume fractions of macro voids for SH-V and SS-V account for up to 50.94 % and 63.64 %, respectively, which are 12.22 % and 7.95 % higher than those of SH-H and SS-H. Regarding the impact of coupled high-temperature and vacuum environment, the compressive strength of SH-HV-7 is reduced by 47.8 % compared to that of SH-H-7, while the compressive strength of SS-HV-7 exhibits a 57.2 % increase over that of SS-H-7. The sodium hydroxide-activated (SH-activated) system and sodium silicate-activated (SS-activated) system demonstrate fundamentally intrinsic differences in terms of reaction products, structure build-up and pore structure. The positive optimization mechanism and reverse degradation effect of vacuum environment on the performance of AALRS paste were revealed. Finally, the evolution of structural characteristics of AALRS paste under different environments was elucidated.

12-Nor-rotenoids and other cytotoxic constituents of Pachyrhizus erosus seeds

Five previously undescribed compounds, including three 12-nor-rotenoids, were isolated from Pachyrhizus erosus seeds. A brief survey on the dealkylation of selected rotenoids with BBr3 was undertaken. Spectroscopic data of these previously undescribed compounds and reaction products are reported. The proposal of absolute configurations at stereocenters in the isolates and reaction products was based on NMR and ECD data. Most of the isolates and reaction products were evaluated for their growth inhibitory activities against four cancer cell lines and a Vero cell line. Many compounds exhibited strong to moderate activities with IC50 values ranging from 0.06 to 20.9 μM, and their structure-activity relationships were evaluated.

Molecular Basis of the Substrate Specificity of Phosphotriesterase from Pseudomonas diminuta: A Combined QM/MM MD and Electron Density Study.

The occurrence of organophosphorus compounds, pesticides, and flame-retardants in wastes is an emerging ecological problem. Bacterial phosphotriesterases are capable of hydrolyzing some of them. We utilize modern molecular modeling tools to study the hydrolysis mechanism of organophosphorus compounds with good and poor leaving groups by phosphotriesterase from Pseudomonas diminuta (Pd-PTE). We compute Gibbs energy profiles for enzymes with different cations in the active site: native Zn2+cations and Co2+cations, which increase the steady-state rate constant. Hydrolysis occurs in two elementary steps via an associative mechanism and formation of the pentacoordinated intermediate. The first step, a nucleophilic attack, occurs with a low energy barrier independently of the substrate. The second step has a low energy barrier and considerable stabilization of products for substrates with good leaving groups. For substrates with poor leaving groups, the reaction products are destabilized relative to the ES complex that suppresses the reaction. The reaction proceeds with low energy barriers for substrates with good leaving groups with both Zn2+and Co2+cations in the active site; thus, the product release is likely to be a limiting step. Electron density and geometry analysis of the QM/MM MD trajectories of the intermediate states with all considered compounds allow us to discriminate substrates by their ability to be hydrolyzed by the Pd-PTE. For hydrolyzable substrates, the cleaving bond between a phosphorus atom and a leaving group is elongated, and electron density depletion is observed on the Laplacian of electron density maps.

Design-driven approach for engineered geopolymer composite with recorded low fiber content

How to design an engineered cementitious composite (ECC) achieving both economic viability and ultra-sustainability has been the longstanding goal of ECC community. This study presents a design-driven approach to tackle this challenge through yielding a low matrix fracture toughness and a sufficiently strong interfacial bonding between fiber and matrix concurrently. As a result, only 0.2 % fiber content was sufficient for achieving robust strain-hardening in Engineered Geopolymer Composite (EGC), which, to the authors’ knowledge, is the lowest recorded thus far. The tensile strain-to-fiber content ratio reached 25, a remarkable 233 % higher than the existing strain-hardening composites. Besides, the compressive strength was around 40 MPa, marking the highest specific strength among the ECCs with a density below 1450 kg/m3. Leveraging the high porosity of 38 % and the presence of shrinkage micro-cracks in the matrix, a low fracture toughness, combined with a robust friction between fiber and matrix, facilitated the noticeable strain-hardening. The reaction product was identified as a dense alkaline aluminosilicate hydrate (N-A-S-H) gel, benefiting the interfacial bonding and compressive strength. The embodied energy and carbon of the EGC diminished by 27 % and 63 % compared to ordinary concrete, respectively, and the corresponding cost was 79 % lower than the classic M45-ECC, contributing significantly to ultra-sustainability.

Three-dimensional phase field modeling, orientation prediction and stress field analyses of twin-twin, twin-grain boundary reactions mediated by disclinations in hexagonal close-packed metals

Crystalline defects, such as dislocations, disclinations, twins and grain boundaries, play critical roles in determining the mechanical properties of metals and alloys. In particular, with multiple competitive deformation modes activated, the mechanical behaviors of hexagonal close-packed metals are strongly influenced by the interactions and reactions of various types of defects. Despite extensive studies on the elastic interactions of defects, a theoretical framework capturing crystallographic reactions, especially reaction products and associated local stress concentration, is still unavailable. Here we suggest a disclination-based method to quantify defect reactions. By using a combination of crystallographic calculations and phase field modeling/simulations, twin-twin and twin-grain boundary reactions in hexagonal close-packed metals have been quantitatively analyzed. It has been found that partial disclinations, accompanied with other defects (e.g., {112¯6} and {112¯2} high-index twins), can be generated by defect reactions as typical byproducts. The orientation change and stress fields caused by disclination formation have been systematically calculated, which offers a rigorous mathematical foundation to explore twin-twin, twin-grain boundary reactions. By quantitatively determining defect reactions and local stress fields, our work provides new insights into the deformation mechanism and microstructure-property relationship in metallic materials.

Combustion synthesis of the (Ti,Zr)B2-(Zr,Ti)C eutectic composites: Structure formation and properties

The macrokinetic characteristics of combustion of the quaternary Ti-Zr-B-C mixture as well as the mechanism and stages of phase formation for the synthesis products were investigated. The mechanical and thermophysical properties of the hot-pressed boride/carbide ceramics with eutectic composition (Ti,Zr)B2-43%at.(Zr,Ti)C were measured. Preliminary mechanical alloying (MA) of the (Zr + Ti) mixture was shown to yield Ti/Zr granules having a laminar structure and consisting of alternating layers of titanium, zirconium, and (Zr,Ti)ss solid solution. The method used to prepare reaction mixtures and the initial temperature T0 increased within the range of 20–370 °C have virtually no effect on combustion temperature, which is 2260–2400 °C, while higher T0 increases the combustion rate by a factor of 1.5–2. The use of MA Ti/Zr granules reduces the combustion rate as well as the specific heat release amount and the heat release rate. Time-resolved X-ray diffraction data showed that binary carbides (Zr1-xTix)C and diborides (Ti1-yZry)B2 of variable stoichiometry are formed in the combustion wave of the Ti-Zr-B-C reaction mixtures within less than 0.25 s. The carbide and diboride phases are formed simultaneously; the use of MA Ti/Zr granules in the reaction mixtures reduces the content of solid solutions of variable stoichiometry among the reaction products. The ceramics fabricated using a combination of combustion synthesis and hot pressing have a dense and homogeneous structure that consist of bonded grains of the diboride (Ti0.80Zr0.20)B2 and carbide (Zr0.83Ti0.17)C phases having the following properties: density, 5.3 g/cm3; hardness, 22.9 GPa; fracture toughness, 4.7 MPa m0.5; heat capacity, 0.52 J/(g·K); thermal diffusivity, 11.67 mm2/s; and thermal conductivity, 33.28 W/(m·K).

Phase evolution and microstructure changes induced by accelerated carbonation in natural hydraulic lime paste with GGBFS addition

Carbonation is a primary factor driving the continuous improvement of the long-term performance of natural hydraulic lime (NHL). This research systematically examines the impact of accelerated carbonation (3 % CO2) on the carbonation depth, phase composition, microstructure, and compressive strength of hardened natural hydraulic lime (NHL) pastes mixed with different amounts of ground granulated blast furnace slag (GGBFS), termed as S-NHL. The findings show that the hydration reaction products of GGBFS and Ca(OH)2 (CH), such as C3AH10, C4AĈH11, and C-S-H, densify the microstructure of S-NHL, resulting in a decrease in carbonation depth with increasing GGBFS content. Accelerated carbonation (AC) promotes the rapid transformation of a significant quantity of CH into calcite in S-NHL, with the carbonation of CH occurring more readily than the carbonation of hydration reaction products. Throughout the AC process, NHL contains only calcite-type calcium carbonate. In contrast, after 28 days of AC, the carbonation of hydration reaction products such as C3AH10 and C-S-H in S-NHL produces a minor amount of aragonite and vaterite. AC continuously reduces the total pore volume and porosity of S-NHL, but the average pore diameter and most probable pore diameter initially decrease and then slightly increase. AC significantly reduces the large pores in S-NHL, ultimately resulting in pores predominantly composed of capillary pores (50–1000 nm). AC facilitates the development of compressive strength in S-NHL paste, with the increase in compressive strength being positively correlated with its CH content.

Analysis of Acoustic Absorption Coefficients and Characterization of Epoxy Adhesive Compositions Based on the Reaction Product of Bisphenol A with Epichlorohydrin Modified with Fillers.

Material development in acoustic engineering plays a significant role in various applications, such as industrial noise control. It is important and relevant to consider alternative materials capable of reducing noise levels in different frequency ranges. One commonly used material in engineering structures is epoxy adhesive compositions. Favoring the use of adhesive compositions are their main characteristics, including weight reduction in structures, corrosion resistance, relatively low manufacturing costs, and high mechanical strength. This paper aims to discuss the relationship between the mechanical properties of modified epoxy adhesives, their structure, and sound absorption efficiency. The subjects of this study were specimens of an epoxy composition in the cured state. Acoustic absorption coefficients were evaluated using a dual-microphone impedance tube, and tensile, compressive, and bending strength properties were determined using a testing machine. The impact strength of the compositions was also investigated. An analysis of the structure of the adhesives in the cured state was carried out using a scanning electron microscope. The test specimens were made from Epidian 5 epoxy resin cured with a polyamide PAC curing agent. Nanobent ZR2 aluminosilicate in an amount of 1%, CaCO3 calcium carbonate in an amount of 5%, and CWZ-22 activated carbon in an amount of 20% were used as modifiers. The conducted studies revealed that the highest tensile strength was obtained for the adhesive composition with the addition of ZR2 filler. The highest compressive strength was exhibited by the adhesive composition with the addition of CWZ-22 filler. The highest flexural strength was demonstrated by the unmodified composition. For all the tested adhesive compositions, low sound absorption values were achieved, with a maximum of approximately 0.18. From the perspective of the reduction index R, it was observed that these samples performed better in reduction than in absorption. The best values were achieved in the compositions modified with CaCO3.

The Crystal Structures of Some Bromo-Derivatives of the DPPH Stable Free Radical

Bromination of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical with bromine or N-bromo-succinimide (NBS) affords a complex mixture of bromo- and nitro-derivatives of the starting material. In this study, by chromatographic separation, most of the reaction products were isolated. Suitable crystals for X-ray measurements were obtained and characterized for the compounds 2-p-bromophenyl-2-phenyl-1-picrylhydrazyl free radical (Br-DPPH), 2-p-bromophenyl-2-phenyl-1-picrylhydrazine (Br-DPPH-H), and 2,2-(p-bromophenyl)-1-(2-bromo-4,6-dinitrophenyl)hydrazine (Br2-DPPBr-H).

Copper-Catalyzed Asymmetric Hydrogenation of Unsymmetrical ortho-Br Substituted Benzophenones.

The asymmetric hydrogenation of benzophenones, catalyzed by low-activity earth-abundant metal copper, has hitherto remained a challenge due to the substrates equipped with two indistinguishably similar aryl groups. In this study, we demonstrated that the prochiral carbon of the ortho-bromine substrate exhibits the highest electrophilicity and high reactivity among the ortho-halogen substituted benzophenones, as determined by the Fukui function (f+) analysis and hydrogenation reaction. Considering that the enantiodirecting functional bromine group can be easily derivatized and removed in the products, we successfully achieved a green copper-catalyzed asymmetric hydrogenation of ortho-bromine substituted benzophenones. This method yielded a series of chiral benzhydrols with excellent results. The utility of this protocol has been validated through a gram-scale reaction and subsequent product transformations. Hirshfeld partition (IGMH) and energy decomposition analysis (EDA) indicate that the CH···HC multiple attractive dispersion interactions (MADI) effect between the catalyst and substrate enhances the catalyst's activity.

Modeling the Combustion-Deflagration-Detonation Transition (CoDDT) in a porous high explosive, comparison with experiments

ABSTRACT A reactive multiphase model stemming from the Baer and Nunziato model was developed and extended to three phases, one solid and two gaseous respectively representing the solid explosive, the initial porosity and the reaction products. It was used to model the transition from deflagration to detonation of a highly confined porous HMX 150–200 explosive thermally initiated, for several initial densities, ranging from 65% to 88% of the material's Theoretical Maximum Density (TMD). The influence of the deconsolidative burning in the critical acceleration of the reactive front was implemented through a fluidization parameter, allowing to switch from pore to grain burning. Other microstructural parameters such as the pores and grains size were determined by careful experimental characterizations presented in Bouchet et al. (2022). The model then succeeded in reproducing the physical mechanisms that were previously experimentally observed, such as the convective burning, the plug formation, and the transition to detonation at the distances that were experimentally measured.

Mutual Transformations of Polysulfide Chromophore Species in Sodalite-Group Minerals: A DFT Study on S6 Decomposition.

It is known that various polysulfide species determine the color of sodalite-group minerals (haüyne, lazurite, and slyudyankaite), and that heating induces their transformations and color change, but the mechanisms of the transitions are unknown. A prominent example is the decay of cyclic S6 molecule. Using density-functional simulations, we explore its main decay pathways into the most probable final reaction products (the pairs of radical anions S3⋅-+S3⋅- and S2⋅-+S4⋅-). It was found that the most favorable reaction path involves initial capture of one electron by the S6 molecule, which greatly facilitates its decay of S6 and leads to the opening of the S6 cycle, and subsequent decomposition of the thus formed chain radical anion, with a limiting energy barrier of ~0.4 eV. Neutral polysulfide molecules capture one electron with a significant energy reduction. The radical anions Sn⋅- (n=2-6) are the most stable ones among corresponding species with the same n values and different charges. The capture of the second electron by S6⋅- occurs with a huge energy barrier (~2 eV). The results of the DFT calculations are in agreement with experimental data on the products of thermal conversions of extra-framework S-bearing groups in sodalite-group minerals.

Nuclear-excited source of coherent and incoherent radiation with direct nuclear pumping

Uranium fission fragments, as well as the products of 3He(n,p)3H and 10B(n,α)7Li nuclear reactions were utilized in the nuclear reactor for gas ionization and excitation. However, the 6Li(n,α)3H nuclear reaction was less examined. The use of lithium-6 as a surface source of excitation of the gas medium, due to the long path length of tritium nuclei in the gas, allows to excite large volumes of gas as opposed to using 235U or 10B.While investigating the luminescence of noble gases in the core of the IVG.1M research reactor, we noted an appearance of alkali metal lines and a sharp increase in the intensity of these lines at temperatures above 570 K. It was determined that the population of levels of lithium atoms has practically no effect on the population of the 2p-levels of atoms of noble gases. The selectivity of p- and s-levels deactivation by lithium atoms implies the possibility of creating inversion of population at 2p-1s transitions of noble gas atoms. Successful experiments to study the luminescence of gases upon excitation by 6Li(n,α)3H nuclear reaction products allow us to proceed to experiments to achieve the laser action threshold and study the lasing characteristics of gas mixtures at the IGR pulsed nuclear reactor with thermal neutron flux density up to 7∙1016 n/cm2s. For this purpose, an experimental device designs were proposed to perform experiments on the IGR reactor. A step-by-step procedure of fabrication of a nuclear-excited source for excitation of gas mixtures is provided. The results of reactor experiments aimed at determining the spectral and temporal characteristics of optical radiation during excitation of gas mixtures by 6Li(n,α)3H nuclear reaction products are presented.

Development of a Superhydrophobic Protection Mechanism and Coating Materials for Cement Concrete Surfaces.

In order to further enhance the erosion resistance of cement concrete pavement materials, this study constructed an apparent rough hydrophobic structure layer by spraying a micro-nano substrate coating on the surface layer of the cement concrete pavement. This was followed by a secondary spray of a hydroxy-silicone oil-modified epoxy resin and a low surface energy-modified substance paste, which combine to form a superhydrophobic coating. The hydrophobic mechanism of the coating was then analysed. Firstly, the effects of different types and ratios of micro-nano substrates on the apparent morphology and hydrophobic performance of the rough structure layer were explored through contact angle testing and scanning electron microscopy (SEM). Subsequently, Fourier transform infrared spectroscopy and permeation gel chromatography were employed to ascertain the optimal modification ratio, temperature, and reaction mechanism of hydroxy-silicone oil with E51 type epoxy resin. Additionally, the mechanical properties of the modified epoxy resin-low surface energy-modified substance paste were evaluated through tensile tests. Finally, the erosion resistance of the superhydrophobic coating was tested under a range of conditions, including acidic, alkaline, de-icer, UV ageing, freeze-thaw cycles and wet wheel wear. The results demonstrate that relying solely on the rough structure of the concrete surface makes it challenging to achieve superhydrophobic performance. A rough structure layer constructed with diamond micropowder and hydrophobic nano-silica is less prone to cracking and can form more "air chamber" structures on the surface, with better wear resistance and hydrophobic performance. The ring-opening reaction products that occur during the preparation of modified epoxy resin will severely affect its mechanical strength after curing. Controlling the reaction temperature and reactant ratio can effectively push the modification reaction of epoxy resin through dehydration condensation, which produces more grafted polymer. It is noteworthy that the grafted polymer content is positively correlated with the hydrophobicity of the modified epoxy resin. The superhydrophobic coating exhibited enhanced erosion resistance (based on hydrochloric acid), UV ageing resistance, abrasion resistance, and freeze-thaw damage resistance to de-icers by 19.41%, 18.36%, 43.17% and 87.47%, respectively, in comparison to the conventional silane-based surface treatment.

High serological and molecular prevalence of Ehrlichia canis and other vector-borne pathogens in dogs from Boa Vista Island, Cape Verde

Despite the high global impacts of canine vector-borne diseases (CVBD) due to their wide distribution and zoonotic potential, the current epidemiological situation of CVBD in many tropical and subtropical regions remains unknown. This study examines the seroprevalence and molecular prevalence of Ehrlichia canis and other pathogens causing CVBDs (Leishmania infantum, Dirofilaria immitis, Babesia spp., Anaplasma spp. and Hepatozoon canis) in dogs living on the island of Boa Vista (Cape Verde Republic). Blood samples and infesting ticks were taken from 150 dogs across the island (stray, shelter, and pet dogs). Serum samples were tested using a rapid immunochromatographic test (Uranotest® Quattro) that detects antibodies against E. canis, L. infantum, Anaplasma spp. and D. immitis antigen. Levels of serum antibodies against E. canis were measured using the immunofluorescence antibody test (IFAT). In addition, tick-borne pathogens in blood samples (Anaplasma spp., Babesia spp., Hepatozoon spp., and Ehrlichia canis) were detected by microscopy observation and/or PCR plus sequencing. The seroprevalence of E. canis was extremely high at 82% (123/150), as revealed by both immunochromatography and IFAT. Most dogs returning a seropositive test result (82.92%; 102/123) had antibody titres > 1:1280 but showed no clinical signs or notable laboratory abnormalities. Of the 123 animals testing seropositive for E. canis, 67 (54.47%) also presented antibodies against Anaplasma spp., and 13 (10.56%) showed the presence of Hepatozoon spp. gamonts in the blood smear. Ehrlichia canis infection was detected in 17.1% (25/146) of dogs tested by direct sequencing of polymerase chain reaction (PCR) products. Co-infections were detected in seven of these dogs: four dogs tested PCR-positive for both E. canis and A. platys, two dogs tested positive for E. canis and Hepatozoon spp., and one dog tested positive for E. canis, A. platys and Hepatozoon spp. Rhipicephalus sanguineus sensu lato was the only tick species found infesting the canine study population. The high prevalence of tick-borne pathogens detected in dogs from Boa Vista Island highlights a need for improved control measures designed to prevent the transmission of these pathogens.Graphical

Revolutionizing CO2‐to‐C2 Conversion: Unleashing the Potential of CeO2 Nanocores for Self‐ Supported Electrocatalysts with Cu2O Nanoflakes on 3D Graphene Aerogel

AbstractCu serves as a promising electrocatalyst for converting CO2 into valuable C2 products in CO2 reduction reactions (CO2RR). However, instability in CO* formation is crucial for CO2 adsorption‐ desorption still remains a challenge under reduction conditions. This study explores the impact of lanthanide oxide, particularly CeO2, on Cu‐based catalytic performances. By leveraging Ce's distinctive electronic structure, CO* species are stabilized during the reaction in CeO2─Cu2O, resulting in exceptional catalytic performance for CO2 electroreduction to C2 products. Hybridizing CeO2‐Cu2O with graphene aerogel enhances electrochemical active surface area and CO2RR efficiency. The resulting CeO2─Cu2O(10%)/GA electrocatalyst exhibits a remarkable faradaic efficiency for C2 products, exceeding 62%, alongside exceptional stability over 80 h with wide potential window (−0.8 to −1.2 V) using a H‐cell. Systematic investigations elucidate the intricate interplay between surface properties and catalytic activity. Furthermore, a solar cell‐ powered CO2 reduction system demonstrates consistent performance (−27.8 mA cm−2 at 3.46 V) under solar radiation of ≈100 mW cm−2, showcasing outstanding stability with nearly 100% retention over 4 h of continuous illumination. In short, by harnessing catalytic and electronic effects, this innovation advances the development of electrocatalysts with heightened CO2‐to‐C2 selectivity, bridging fundamental research with technological innovation to tackle critical global challenges.