Background:Pistacia chinensis Bunge has been traditionally used to manage various conditions,including asthma,pain,inflammation,hepatoprotection,and diabetes.The study was conducted to investigate the antioxidant and ...Background:Pistacia chinensis Bunge has been traditionally used to manage various conditions,including asthma,pain,inflammation,hepatoprotection,and diabetes.The study was conducted to investigate the antioxidant and anti-lipoxygenase(LOX)properties of the isolated compound 2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-4H-chromen-4-one from Pistacia chinensis.Methods:LOX assay and antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl(DPPH)assay were performed.Molecular docking studies were conducted using a molecular operating environment.Results:The LOX assay revealed significant inhibitory effects at 0.2µM concentration,with an IC50 value of 37.80µM.The antioxidant effect demonstrated dose-dependency across 5 to 100µg/mL concentrations,reaching 93.09%at 100µg/mL,comparable to ascorbic acid’s 95.43%effect.Molecular docking studies highlighted strong interactions with the lipoxygenase enzyme,presenting an excellent docking score of-10.98 kcal/mol.Conclusion:These findings provide valuable insights into Pistacia chinensis’chemical components and biological effects,reinforcing its traditional medicinal applications.展开更多
Biodegradable implants have emerged in biomedical applications,particularly for orthopedic fixations,cardiovascular stents,and tissue engineering scaffolds.Unlike permanent implants,they are designed to degrade and be...Biodegradable implants have emerged in biomedical applications,particularly for orthopedic fixations,cardiovascular stents,and tissue engineering scaffolds.Unlike permanent implants,they are designed to degrade and be reabsorbed after implantation in the body,mitigating the need for additional surgeries and reducing associated complications.In particular,Fe-Mn-C alloys constitute a new class of promising metallic materials for medical applications due to their outstanding mechanical properties and their bio-logical performances.This study focuses on improving the degradation rates and cytotoxicity of sintered Fe-Mn-C alloys produced using the powder metallurgy process.To evaluate the impact of different pow-der preparation methods on material properties,two types of powders were used:(1)MX,prepared by mixing Fe,Mn,and C powders for 1 h;and(2)MM,obtained by mechanically milling the same powders for 10 h.Four mixtures with varying proportions of MX and MM were prepared.Two groups of samples were produced:one entirely from MX(A0),and another containing MM at 25 wt.%(A25),50 wt.%(A50),and 75 wt.%(A75).All samples exhibited a complex microstructure comprising ferrite,martensite,and residual austenite.Degradation behavior assessment in Hanks’solution over 14 days showed that adding MM increased the degradation rate,from around 0.04 mmpy for A0 to 0.12 mmpy for A25.Notably,all samples showed similar cell viability,in the range of 83%-89%for 1%extract dilution,and were non-hemolytic,with a hemolysis percentage below 1%.展开更多
This work aimed to study the efficiency of the reverse micelle(RM)preparation route in the syntheses of sub-5 nm Fe-doped CeO_(2)nanocrystals for boosting the visible-light-driven photocatalytic hydrogen production fr...This work aimed to study the efficiency of the reverse micelle(RM)preparation route in the syntheses of sub-5 nm Fe-doped CeO_(2)nanocrystals for boosting the visible-light-driven photocatalytic hydrogen production from methanol aqueous solutions.The effectiveness of confining precipitation reactions within micellar cages was evaluated through extensive physicochemical cha racterization.In particula r,the nominal composition(0-5 mol%Fe)was preserved as ascertained by ICP-MS analysis,and the absence of separate iron-containing crystalline phases was supported by X-ray diffraction.The effective aliovalent doping and modulation of the optical properties were investigated using UV-Vis,Raman,and photoluminescence spectroscopies.2.5 mol%iron was found to be an optimal content to achieve a significant decrease in the band gap,enhance the concentration of oxygen vacancy defects,and increase the charge carrier lifetime.The photocatalytic activity of Fe-doped CeO_(2)prepared at different Fe contents with RM preparation was studied and compared with undoped CeO_(2).The optimal iron load was identified to be2.5 mol%,achieving the highest hydrogen production(7566μmol L-1after 240 min under visible light).Moreover,for comparison,the conventional precipitation(P)method was adopted to prepare iron containing CeO_(2)at the optimal content(2.5 mol%Fe).The Fe-doped CeO_(2)catalyst prepared by RM showed a significantly higher hydrogen production than that obtained with the sample prepared by the P method.The optimal Fe-doped CeO_(2),prepared by the RM method,was stable for six reuse cycles.Moreover,the role of water in the mechanism of photocatalytic hydrogen evolution under visible light was studied through the test in the presence of D2O.The obtained results evidenced that hydrogen was produced from the reduction of H^(+)by the electrons promoted in the conduction band,while methanol was preferentially oxidized by the photogenerated positive holes.展开更多
Infrared thermography has been widely applied in real industrial inspection of aerospace,energy management systems,engines,and electric systems.However,two-dimensional imaging modality limits its development.Here,a te...Infrared thermography has been widely applied in real industrial inspection of aerospace,energy management systems,engines,and electric systems.However,two-dimensional imaging modality limits its development.Here,a technique named frequency multiplexed photothermal correlation tomography(FM-PCT)was developed to enable non-destructive and contactless cross-sectional imaging for manufactured material evaluation and characterization.By combining advantages of photothermal tomography and pulsed thermography,FM-PCT facilitates the generation of three-dimensional thermal images through temporal superposition(stacking)of two-dimensional images from sequential subsurface depths.FM-PCT image processing involves pulsed excitation signals to which frequency delay and matched filtering techniques are applied.Major features of FM-PCT are high-resolution three-dimensional tomographic imaging under low camera frame-rate conditions with self-correcting capability for diffusion(blurring)correction of subsurface images due to cross-correlation processing of individual frequencies in the Fourier decomposition spectrum of the excitation pulse.Furthermore,FM-PCT extends truncated-correlation photothermal coherence tomography from chirp and pulsed signals to more general linear heating sources.Lock-in thermography and x-ray computed tomography validation demonstrate that 3D FM-PCT imaging accurately reveals subsurface discontinuities/defects in solids despite the diffusive nature of thermal-wave imaging.展开更多
This study proposes a novel and sustainable method for fabricating 3D-printed carbon-based electrodes for electrochemical wastewater treatment.We prepared B,N-doped carbon electrodes with hierarchical porosity and a s...This study proposes a novel and sustainable method for fabricating 3D-printed carbon-based electrodes for electrochemical wastewater treatment.We prepared B,N-doped carbon electrodes with hierarchical porosity and a significantly enhanced surface area-to-volume ratio(up to 180%)compared to non-optimized analogues using a synergistic combination of 3D printing,phase inversion,and microwave plasma-enhanced chemical vapor deposition.This process allows the metal-free growth of vertically aligned carbon nanostructures directly onto polymer-derived substrates,resulting in a 20-fold increase in the electrochemically active surface area.Computational fluid dynamics simulations were used to improve mass transport and reduce pressure drop.Electrochemical characterization demonstrated that the optimized electrodes performed significantly better,achieving 4.7-,4-,and 6.5-fold increases in the degradation rates of atenolol,metoprolol,and propranolol,respectively,during electrochemical oxidation.These results highlight the efficacy of the integrated fabrication and simulation approach in producing high-performance electrodes for sustainable wastewater treatment applications.展开更多
Background:Pistacia integerrima,a cornerstone of traditional medicine,is renowned for its therapeutic applications against various health conditions,including cancer and hepatitis.This study investigates the pharmacol...Background:Pistacia integerrima,a cornerstone of traditional medicine,is renowned for its therapeutic applications against various health conditions,including cancer and hepatitis.This study investigates the pharmacological potential of bioactive compounds derived from Pistacia integerrima in inhibiting 5-lipoxygenase(5-LOX),a key enzyme implicated in inflammation and cancer progression.The current study aimed to evaluate the lipoxygenase inhibitory activity of bioactive compounds from Pistacia integerrima and assess their potential for therapeutic development in the context of inflammation and cancer treatment.Methods:Three major compounds-spinacetin(1),patuletin(2),and pistagremic acid(3)-were isolated from Pistacia integerrima and analyzed for their lipoxygenase inhibitory activity.Biochemical assays and molecular docking studies were performed to assess their effectiveness in inhibiting 5-LOX.Results:All three compounds demonstrated significant inhibition of lipoxygenase activity.Spinacetin(1)and patuletin(2)exhibited the most potent inhibitory effects,with IC_(50)values of 40.34μM and 45.04μM,respectively.Molecular docking studies revealed that patuletin(2)had the highest binding affinity(−7.717 kcal/mol)against 5-LOX,followed by spinacetin(1)with a binding affinity of−6.074 kcal/mol.In-depth in silico analysis highlighted the drug-likeness of spinacetin(1)and its favorable toxicological profile,suggesting its suitability for therapeutic development.Conclusion:The study demonstrates that compounds from Pistacia integerrima,particularly spinacetin and patuletin,have significant lipoxygenase inhibitory activity,with spinacetin showing promise as a lead candidate for lipoxygenase-targeted therapies.The findings reinforce the therapeutic relevance of Pistacia integerrima and suggest that its bioactive compounds may serve as safer,plant-based alternatives to conventional anti-inflammatory and anticancer treatments.展开更多
Palladium based catalysts are the most active for methane oxidation. The tuning of their composition, structure and morphology at macro and nanoscale can alter significantly their catalytic behavior and robustness wit...Palladium based catalysts are the most active for methane oxidation. The tuning of their composition, structure and morphology at macro and nanoscale can alter significantly their catalytic behavior and robustness with a strong impact on their overall performances. Among the several combinations of supports and promoters that have been utilized, Pd/CeO2 has attracted a great attention due to its activity and durability coupled with the unusually high degree of interaction between Pd/Pd O and the support. This allows the creation of specific structural arrangements which profoundly impact on methane activation characteristics. Here we want to review the latest findings in this area, and particularly to envisage how the control(when possible) of Pd-CeO2 interaction at nanoscale can help in designing more robust methane oxidation catalysts.展开更多
This essay analyses some of the recent development in nanocarbons (carbon materials having a defined and controlled nano-scale dimension and functional properties which strongly depend on their nano-scale features and...This essay analyses some of the recent development in nanocarbons (carbon materials having a defined and controlled nano-scale dimension and functional properties which strongly depend on their nano-scale features and architecture), with reference to their use as advanced catalytic materials. It is remarked how their features open new possibilities for catalysis and that they represent a new class of catalytic materials. Although carbon is used from long time in catalysis as support and electrocatalytic applications, nanocarbons offer unconventional ways for their utilization and to address some of the new challenges deriving from moving to a more sustainable future. This essay comments how nanocarbons are a key element to develop next-generation catalytic materials, but remarking that this goal requires overcoming some of the actual limits in current research. Some aspects are discussed to give a glimpse on new directions and needs for R&D to progress in this direction.展开更多
Nanocarbon materials play a critical role in the development of new or improved technologies and devices for sustainable production and use of renewable energy. This perspective paper defines some of the trends and ou...Nanocarbon materials play a critical role in the development of new or improved technologies and devices for sustainable production and use of renewable energy. This perspective paper defines some of the trends and outlooks in this exciting area, with the effort of evidencing some of the possibilities offered from the growing level of knowledge, as testified from the exponentially rising number of publications, and putting bases for a more rational design of these nanomaterials. The basic members of the new carbon family are fullerene, graphene, and carbon nanotube. Derived from them are carbon quantum dots, nanohorn, nanofiber, nano ribbon, nanocapsulate, nanocage and other nanomorphologies. Second generation nanocarbons are those which have been modified by surface functionalization or doping with heteroatoms to create specific tailored properties. The third generation of nanocarbons is the nanoarchitectured supramolecular hybrids or composites of the first and second genera- tion nanocarbons, or with organic or inorganic species. The advantages of the new carbon materials, relating to the field of sustainable energy, are discussed, evidencing the unique properties that they offer for developing next generation solar devices and energy storage solutions.展开更多
Recent advances on the use of nanocarbon-based electrodes for the electrocatalytic conversion of gaseous streams of CO2 to liquid fuels are discussed in this perspective paper. A novel gas-phase electrocatalytic cell,...Recent advances on the use of nanocarbon-based electrodes for the electrocatalytic conversion of gaseous streams of CO2 to liquid fuels are discussed in this perspective paper. A novel gas-phase electrocatalytic cell, different from the typical electrochemical systems working in liquid phase, was developed. There are several advantages to work in gas phase, e.g. no need to recover the products from a liquid phase and no problems of CO2 solubility, etc. Operating under these conditions and using electrodes based on metal nanoparticles supported over carbon nanotube （CNT） type materials, long C-chain products （in particular isopropanol under optimized conditions, but also hydrocarbons up to C8-C9） were obtained from the reduction of CO2. Pt-CNT are more stable and give in some cases a higher productivity, but Fe-CNT, particular using N-doped carbon nanotubes, give excellent properties and are preferable to noble-metal-based electrocatalysts for the lower cost. The control of the localization of metal particles at the inner or outer surface of CNT is an importact factor for the product distribution. The nature of the nanocarbon substrate also plays a relevant role in enhancing the productivity and tuning the selectivity towards long C-chain products. The electrodes for the electrocatalytic conversion of CO2 are part of a photoelectrocatalytic （PEC） solar cell concept, aimed to develop knowledge for the new generation artificial leaf-type solar cells which can use sunlight and water to convert CO2 to fuels and chemicals. The CO2 reduction to liquid fuels by solar energy is a good attempt to introduce renewables into the existing energy and chemical infrastructures, having a higher energy density and easier transport/storage than other competing solutions （i.e. H2）.展开更多
After short introducing the crucial role of e‐fuels to meet net‐zero emissions targets,this perspective paper discusses the differences between reactive catalysis(electro‐,photo‐and plasma‐catalysis,with focus on...After short introducing the crucial role of e‐fuels to meet net‐zero emissions targets,this perspective paper discusses the differences between reactive catalysis(electro‐,photo‐and plasma‐catalysis,with focus on the first for conciseness)and thermal catalysis used at most.The main point is to evidence that to progress in producing e‐fuels,the gap is not in terms of scaling‐up and pilot testing,but rather in the fundamental needs to turn the current approach and methodologies to develop reactive catalysis,including from a mechanistic perspective,to go beyond the current methods largely derived from thermal catalysis.Developing thus new fundamental bases to understand reactive catalysis is the challenge to accelerate the progress in this area to enable the potential role towards a sustainable net‐zero emissions future.Some novel aspects are highlighted,but the general aim is rather to stimulate discussion in rethinking catalysis from an alternative perspective.展开更多
The direct electrocatalytic synthesis of ammonia from N2 and H2O by using renewable energy sources and ambient pressure/temperature operations is a breakthrough technology,which can reduce by over 90%the greenhouse ga...The direct electrocatalytic synthesis of ammonia from N2 and H2O by using renewable energy sources and ambient pressure/temperature operations is a breakthrough technology,which can reduce by over 90%the greenhouse gas emissions of this chemical and energy storage process.We report here an in-situ electrochemical activation method to prepare Fe2O3-CNT(iron oxide on carbon nanotubes)electrocatalysts for the direct ammonia synthesis from N2 and H2O.The in-situ electrochemical activation leads to a large increase of the ammonia formation rate and Faradaic efficiency which reach the surprising high values of 41.6μg mgcat^−1 h^−1 and 17%,respectively,for an in-situ activation of 3 h,among the highest values reported so far for non-precious metal catalysts that use a continuous-flow polymer-electrolytemembrane cell and gas-phase operations for the ammonia synthesis hemicell.The electrocatalyst was stable at least 12 h at the working conditions.Tests by switching N2 to Ar evidence that ammonia was formed from the gas-phase nitrogen.The analysis of the changes of reactivity and of the electrocatalyst characteristics as a function of the time of activation indicates a linear relationship between the ammonia formation rate and a specific XPS(X-ray-photoelectron spectroscopy)oxygen signal related to O2−in iron-oxide species.This results together with characterization data by TEM and XRD suggest that the iron species active in the direct and selective synthesis of ammonia is a maghemite-type iron oxide,and this transformation from the initial hematite is responsible for the in-situ enhancement of 3-4 times of the TOF(turnover frequency)and NH3 Faradaic efficiency.This transformation is likely related to the stabilization of the maghemite species at CNT defect sites,although for longer times of preactivation a sintering occurs with a loss of performances.展开更多
The crystalline materials Ca3Sc2Si3O12 and Ca3Y2Si3O12 Were characterized by different crystal structures, as the fonmer is a cubic garnet, while the latter is an orthorhombic compound. We investigated the optical spe...The crystalline materials Ca3Sc2Si3O12 and Ca3Y2Si3O12 Were characterized by different crystal structures, as the fonmer is a cubic garnet, while the latter is an orthorhombic compound. We investigated the optical spectroscopy of these materials doped with several trivalent lanthanide ions and compared the results for the two hosts. PolycrystaUine samples were prepared by solid state reaction, both undoped and doped with the trivalent lanthanide ions Eu3＋, Tb3＋ and Sm3＋. Emission, excitation and Raman spectra of these materials were measured at temperatures ranging from 300 to 10 K. The optical spectra were assigned and discussed, and the effects of the crystal structure of the host on the spectroscopic behaviour were addressed. The technological potential of these compounds in the field of optical materials and devices was discussed,展开更多
The Eu(Ⅲ)nitrate complex of the meso-N,N’-bis(2-pyridylmethylene)-1,2-(R,S)-cyclohexanediamine ligand was synthesized and characterized by single crystal and powder X-ray diffraction.The crystal lattice of the compl...The Eu(Ⅲ)nitrate complex of the meso-N,N’-bis(2-pyridylmethylene)-1,2-(R,S)-cyclohexanediamine ligand was synthesized and characterized by single crystal and powder X-ray diffraction.The crystal lattice of the complex is capable of absorbing and desorbing selectively acetonitrile molecules,at 293 K upon an acetonitrile vapor pressure of^0.1×10^5 Pa.This process,which is partially reversible,can be easily followed by both powder X-ray diffraction(P-XRD)and Eu(III)luminescence spectroscopy.The acetonitrile molecule,located in the outer coordination sphere of the metal ion,does not affect the radiative transition probability of 5 D0 level of Eu(Ⅲ)and also it does not activate further non-radiative channels from this level.On the other hand,this molecule is capable of affecting the energy position and intensities of the crystal field components of the 5 D0→7 F2 transition.The complex in solid form can be considered a promising material for the optical sensing of acetonitrile vapors.展开更多
Two families of catalysts, based on Pd nanoparticles supported on ceramic asymmetric tubular alumina membranes, are studies in the direct synthesis of H2O2. They are prepared by depositing Pd in two ways：（i） reduct...Two families of catalysts, based on Pd nanoparticles supported on ceramic asymmetric tubular alumina membranes, are studies in the direct synthesis of H2O2. They are prepared by depositing Pd in two ways：（i） reduction with N2H4 in an ultrasonic bath and（ii） by impregnation-deposition. The first preparation leads to larger particles, with average size of around 11 nm, while the second preparation leads to smaller particles, with average size around 4 nm. The catalytic membranes were tested as prepared, after thermal treatment in air and after further pre-reduction with H2 in mild（100 ℃） conditions. Samples were characterized by TEM, CO-chemisorption monitored by DRIFTS method and TPR, while catalytic tests have been performed in a semi-batch recirculation membrane reactor. Experimental catalytic results were analysed using two kinetics models to derive the reaction constants for the parallel and consecutive reactions of the kinetic network. Smaller particles of Pd show lower selectivity due to the higher rate of parallel combustion, even if the better dispersion of Pd and thus higher metal surface area in the sample lead to a productivity in H2O2 similar or even higher than the sample with the larger Pd particles. Independently on the presence of smaller or larger Pd nanoparticles, an oxidation treatment leads to a significant enhancement in the productivity, although the catalyst progressively reduces during the catalytic process. The inhibition of the parallel combustion reaction（to water） induced from the calcination treatment remains after the in-situ reduction of the oxidized Pd species formed during the pre-treatment.This is likely due to the elimination of defect sites which dissociatively activate oxygen, and tentatively attributed to Pd sites able to give three- and four-fold coordination of CO.展开更多
Novel fully biodegradable thermoplastic composite laminates reinforced with ultrathin wood laminae were prepared through a hot-pressing process by using two different thermoplastic starch(TPS)matrices.The microstructu...Novel fully biodegradable thermoplastic composite laminates reinforced with ultrathin wood laminae were prepared through a hot-pressing process by using two different thermoplastic starch(TPS)matrices.The microstructure and physical properties of the resulting unidirectional and bidirectional laminates were studied.The investigated materials presented a complex microstructure,in which the porosity of the wood laminae was almost entirely occluded by the polymer matrix.The mechanical behavior of the laminates was strongly affected by the obtained microstructure,and matrix penetration in wood pores led to biodegradable composites with elastic modulus and tensile strength higher than those of their constituents.Finally,thermal welding and thermoformability tests proved how these materials possess features typical of thermoplastic materials.展开更多
The changing energy-chemistry nexus is discussed in this perspective paper about the future of sustainable energy and chemical production to identify the priorities and open issues on which focus research and developm...The changing energy-chemistry nexus is discussed in this perspective paper about the future of sustainable energy and chemical production to identify the priorities and open issues on which focus research and development. Topics discussed regard （i） the new sustainable energy scenario, （ii） the role of energy storage （from smart grids to chemical storage of energy）, （iii） the outlooks and role of solar （bio）refineries and solar fuels, （iv） how to integrate hio- and solar-refineries to move to new economy, （v） the role of methanol at the crossover of new energy-chemistry nexus, （vi） the role of chemistry in this new scenario, （vii） the role of nanomaterials for a sustainable energy, （viii） the use of nanocarbons to design advanced energy conversion and storage devices, and （ix） possibilities and routes to exploit solar energy and methane （shale gas）. The contribution provides a glimpse of the emerging directions and routes with some elements about their possible role in the future scenario, but does not orovide a detailed analysis of the state of the art in these directions展开更多
Electrodes prepared by anodic oxidation of Ti foils are robust and not toxic materials for the electrocatalytic reduction of oxalic acid to glycolic acid, allowing the development of a renewable energy-driven process ...Electrodes prepared by anodic oxidation of Ti foils are robust and not toxic materials for the electrocatalytic reduction of oxalic acid to glycolic acid, allowing the development of a renewable energy-driven process for producing an alcoholic compound from an organic acid at low potential and room temperature. Coupled with the electrochemical synthesis of the oxalic acid from CO_(2),this process represents a new green and low-carbon path to produce added value chemicals from CO_(2). Various electrodes prepared by anodic oxidation of Ti foils were investigated. They were characterized by the presence of a TiO_(2) nanotube array together with the presence of small patches, debris, or TiO_(2) nanoparticles. The concentration of oxygen vacancies, the amount of Ti^(3+) measured by X-ray photoelectron spectroscopy(XPS) and the intensity of the anodic peak measured by cyclic voltammetry, were positively correlated with the achieved oxalic acid conversion and glycolic acid yield. The analysis of the results indicates the presence of small amorphous TiO_(2) nanoparticles(or surface patches or debris) interacting with TiO_(2) nanotubes, the sites responsible for the conversion of oxalic acid and glycolic acid yield. By varying this structural characteristic of the electrodes, it is possible to tune the glycolic acid to glyoxylic acid relative ratio. A best cumulative Faradaic efficiency(FE) of about 84% with FE to glycolic acid around 60% and oxalic conversion about 30% was observed.展开更多
文摘Background:Pistacia chinensis Bunge has been traditionally used to manage various conditions,including asthma,pain,inflammation,hepatoprotection,and diabetes.The study was conducted to investigate the antioxidant and anti-lipoxygenase(LOX)properties of the isolated compound 2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-4H-chromen-4-one from Pistacia chinensis.Methods:LOX assay and antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl(DPPH)assay were performed.Molecular docking studies were conducted using a molecular operating environment.Results:The LOX assay revealed significant inhibitory effects at 0.2µM concentration,with an IC50 value of 37.80µM.The antioxidant effect demonstrated dose-dependency across 5 to 100µg/mL concentrations,reaching 93.09%at 100µg/mL,comparable to ascorbic acid’s 95.43%effect.Molecular docking studies highlighted strong interactions with the lipoxygenase enzyme,presenting an excellent docking score of-10.98 kcal/mol.Conclusion:These findings provide valuable insights into Pistacia chinensis’chemical components and biological effects,reinforcing its traditional medicinal applications.
基金supported by the Natural Science and En-gineering Research Council of Canada(Discovery and Alliance),and PRIMA(Quebec Ministry for Economy and Innovation).
文摘Biodegradable implants have emerged in biomedical applications,particularly for orthopedic fixations,cardiovascular stents,and tissue engineering scaffolds.Unlike permanent implants,they are designed to degrade and be reabsorbed after implantation in the body,mitigating the need for additional surgeries and reducing associated complications.In particular,Fe-Mn-C alloys constitute a new class of promising metallic materials for medical applications due to their outstanding mechanical properties and their bio-logical performances.This study focuses on improving the degradation rates and cytotoxicity of sintered Fe-Mn-C alloys produced using the powder metallurgy process.To evaluate the impact of different pow-der preparation methods on material properties,two types of powders were used:(1)MX,prepared by mixing Fe,Mn,and C powders for 1 h;and(2)MM,obtained by mechanically milling the same powders for 10 h.Four mixtures with varying proportions of MX and MM were prepared.Two groups of samples were produced:one entirely from MX(A0),and another containing MM at 25 wt.%(A25),50 wt.%(A50),and 75 wt.%(A75).All samples exhibited a complex microstructure comprising ferrite,martensite,and residual austenite.Degradation behavior assessment in Hanks’solution over 14 days showed that adding MM increased the degradation rate,from around 0.04 mmpy for A0 to 0.12 mmpy for A25.Notably,all samples showed similar cell viability,in the range of 83%-89%for 1%extract dilution,and were non-hemolytic,with a hemolysis percentage below 1%.
基金funding from the"Ministero dell'Universitàe della Ricerca(MUR)"(Italy)under the"Dipartimento di Eccellenza 2018-2022"program.
文摘This work aimed to study the efficiency of the reverse micelle(RM)preparation route in the syntheses of sub-5 nm Fe-doped CeO_(2)nanocrystals for boosting the visible-light-driven photocatalytic hydrogen production from methanol aqueous solutions.The effectiveness of confining precipitation reactions within micellar cages was evaluated through extensive physicochemical cha racterization.In particula r,the nominal composition(0-5 mol%Fe)was preserved as ascertained by ICP-MS analysis,and the absence of separate iron-containing crystalline phases was supported by X-ray diffraction.The effective aliovalent doping and modulation of the optical properties were investigated using UV-Vis,Raman,and photoluminescence spectroscopies.2.5 mol%iron was found to be an optimal content to achieve a significant decrease in the band gap,enhance the concentration of oxygen vacancy defects,and increase the charge carrier lifetime.The photocatalytic activity of Fe-doped CeO_(2)prepared at different Fe contents with RM preparation was studied and compared with undoped CeO_(2).The optimal iron load was identified to be2.5 mol%,achieving the highest hydrogen production(7566μmol L-1after 240 min under visible light).Moreover,for comparison,the conventional precipitation(P)method was adopted to prepare iron containing CeO_(2)at the optimal content(2.5 mol%Fe).The Fe-doped CeO_(2)catalyst prepared by RM showed a significantly higher hydrogen production than that obtained with the sample prepared by the P method.The optimal Fe-doped CeO_(2),prepared by the RM method,was stable for six reuse cycles.Moreover,the role of water in the mechanism of photocatalytic hydrogen evolution under visible light was studied through the test in the presence of D2O.The obtained results evidenced that hydrogen was produced from the reduction of H^(+)by the electrons promoted in the conduction band,while methanol was preferentially oxidized by the photogenerated positive holes.
基金the National Key Research and Development Program of China(2023YFE0197800)the Natural Sciences and Engineering Research Council of Canada(NSERC)through the CREATE-oN DuTy!Program(496439-2017)+5 种基金the Canada Research Chair in Multi-polar Infrared Vision(MIVIM)the Canada Foundation for Innovationthe Natural Sciences and Engineering Research Council(NSERC)Discovery Grants Program(RGPIN-2020-04595)the Canada Foundation for Innovation(CFI)Research Chairs Program(950-230876)the New Frontiers in Research Fund—Exploration(NFRFE-2019-00647)the CFI-JELF program(38794)。
文摘Infrared thermography has been widely applied in real industrial inspection of aerospace,energy management systems,engines,and electric systems.However,two-dimensional imaging modality limits its development.Here,a technique named frequency multiplexed photothermal correlation tomography(FM-PCT)was developed to enable non-destructive and contactless cross-sectional imaging for manufactured material evaluation and characterization.By combining advantages of photothermal tomography and pulsed thermography,FM-PCT facilitates the generation of three-dimensional thermal images through temporal superposition(stacking)of two-dimensional images from sequential subsurface depths.FM-PCT image processing involves pulsed excitation signals to which frequency delay and matched filtering techniques are applied.Major features of FM-PCT are high-resolution three-dimensional tomographic imaging under low camera frame-rate conditions with self-correcting capability for diffusion(blurring)correction of subsurface images due to cross-correlation processing of individual frequencies in the Fourier decomposition spectrum of the excitation pulse.Furthermore,FM-PCT extends truncated-correlation photothermal coherence tomography from chirp and pulsed signals to more general linear heating sources.Lock-in thermography and x-ray computed tomography validation demonstrate that 3D FM-PCT imaging accurately reveals subsurface discontinuities/defects in solids despite the diffusive nature of thermal-wave imaging.
基金the National Science Centre,Poland,under the Agreement 2022/45/B/ST8/02847 is acknowledged(M.P.).
文摘This study proposes a novel and sustainable method for fabricating 3D-printed carbon-based electrodes for electrochemical wastewater treatment.We prepared B,N-doped carbon electrodes with hierarchical porosity and a significantly enhanced surface area-to-volume ratio(up to 180%)compared to non-optimized analogues using a synergistic combination of 3D printing,phase inversion,and microwave plasma-enhanced chemical vapor deposition.This process allows the metal-free growth of vertically aligned carbon nanostructures directly onto polymer-derived substrates,resulting in a 20-fold increase in the electrochemically active surface area.Computational fluid dynamics simulations were used to improve mass transport and reduce pressure drop.Electrochemical characterization demonstrated that the optimized electrodes performed significantly better,achieving 4.7-,4-,and 6.5-fold increases in the degradation rates of atenolol,metoprolol,and propranolol,respectively,during electrochemical oxidation.These results highlight the efficacy of the integrated fabrication and simulation approach in producing high-performance electrodes for sustainable wastewater treatment applications.
文摘Background:Pistacia integerrima,a cornerstone of traditional medicine,is renowned for its therapeutic applications against various health conditions,including cancer and hepatitis.This study investigates the pharmacological potential of bioactive compounds derived from Pistacia integerrima in inhibiting 5-lipoxygenase(5-LOX),a key enzyme implicated in inflammation and cancer progression.The current study aimed to evaluate the lipoxygenase inhibitory activity of bioactive compounds from Pistacia integerrima and assess their potential for therapeutic development in the context of inflammation and cancer treatment.Methods:Three major compounds-spinacetin(1),patuletin(2),and pistagremic acid(3)-were isolated from Pistacia integerrima and analyzed for their lipoxygenase inhibitory activity.Biochemical assays and molecular docking studies were performed to assess their effectiveness in inhibiting 5-LOX.Results:All three compounds demonstrated significant inhibition of lipoxygenase activity.Spinacetin(1)and patuletin(2)exhibited the most potent inhibitory effects,with IC_(50)values of 40.34μM and 45.04μM,respectively.Molecular docking studies revealed that patuletin(2)had the highest binding affinity(−7.717 kcal/mol)against 5-LOX,followed by spinacetin(1)with a binding affinity of−6.074 kcal/mol.In-depth in silico analysis highlighted the drug-likeness of spinacetin(1)and its favorable toxicological profile,suggesting its suitability for therapeutic development.Conclusion:The study demonstrates that compounds from Pistacia integerrima,particularly spinacetin and patuletin,have significant lipoxygenase inhibitory activity,with spinacetin showing promise as a lead candidate for lipoxygenase-targeted therapies.The findings reinforce the therapeutic relevance of Pistacia integerrima and suggest that its bioactive compounds may serve as safer,plant-based alternatives to conventional anti-inflammatory and anticancer treatments.
文摘Palladium based catalysts are the most active for methane oxidation. The tuning of their composition, structure and morphology at macro and nanoscale can alter significantly their catalytic behavior and robustness with a strong impact on their overall performances. Among the several combinations of supports and promoters that have been utilized, Pd/CeO2 has attracted a great attention due to its activity and durability coupled with the unusually high degree of interaction between Pd/Pd O and the support. This allows the creation of specific structural arrangements which profoundly impact on methane activation characteristics. Here we want to review the latest findings in this area, and particularly to envisage how the control(when possible) of Pd-CeO2 interaction at nanoscale can help in designing more robust methane oxidation catalysts.
基金supported by MIUR/Italy (PRIN10-11Project Mechanisms of CO2 Activation)
文摘This essay analyses some of the recent development in nanocarbons (carbon materials having a defined and controlled nano-scale dimension and functional properties which strongly depend on their nano-scale features and architecture), with reference to their use as advanced catalytic materials. It is remarked how their features open new possibilities for catalysis and that they represent a new class of catalytic materials. Although carbon is used from long time in catalysis as support and electrocatalytic applications, nanocarbons offer unconventional ways for their utilization and to address some of the new challenges deriving from moving to a more sustainable future. This essay comments how nanocarbons are a key element to develop next-generation catalytic materials, but remarking that this goal requires overcoming some of the actual limits in current research. Some aspects are discussed to give a glimpse on new directions and needs for R&D to progress in this direction.
基金the financial support by MOST (2011CBA00504)NSFC (21133010, 50921004, 212111074) of China
文摘Nanocarbon materials play a critical role in the development of new or improved technologies and devices for sustainable production and use of renewable energy. This perspective paper defines some of the trends and outlooks in this exciting area, with the effort of evidencing some of the possibilities offered from the growing level of knowledge, as testified from the exponentially rising number of publications, and putting bases for a more rational design of these nanomaterials. The basic members of the new carbon family are fullerene, graphene, and carbon nanotube. Derived from them are carbon quantum dots, nanohorn, nanofiber, nano ribbon, nanocapsulate, nanocage and other nanomorphologies. Second generation nanocarbons are those which have been modified by surface functionalization or doping with heteroatoms to create specific tailored properties. The third generation of nanocarbons is the nanoarchitectured supramolecular hybrids or composites of the first and second genera- tion nanocarbons, or with organic or inorganic species. The advantages of the new carbon materials, relating to the field of sustainable energy, are discussed, evidencing the unique properties that they offer for developing next generation solar devices and energy storage solutions.
文摘Recent advances on the use of nanocarbon-based electrodes for the electrocatalytic conversion of gaseous streams of CO2 to liquid fuels are discussed in this perspective paper. A novel gas-phase electrocatalytic cell, different from the typical electrochemical systems working in liquid phase, was developed. There are several advantages to work in gas phase, e.g. no need to recover the products from a liquid phase and no problems of CO2 solubility, etc. Operating under these conditions and using electrodes based on metal nanoparticles supported over carbon nanotube （CNT） type materials, long C-chain products （in particular isopropanol under optimized conditions, but also hydrocarbons up to C8-C9） were obtained from the reduction of CO2. Pt-CNT are more stable and give in some cases a higher productivity, but Fe-CNT, particular using N-doped carbon nanotubes, give excellent properties and are preferable to noble-metal-based electrocatalysts for the lower cost. The control of the localization of metal particles at the inner or outer surface of CNT is an importact factor for the product distribution. The nature of the nanocarbon substrate also plays a relevant role in enhancing the productivity and tuning the selectivity towards long C-chain products. The electrodes for the electrocatalytic conversion of CO2 are part of a photoelectrocatalytic （PEC） solar cell concept, aimed to develop knowledge for the new generation artificial leaf-type solar cells which can use sunlight and water to convert CO2 to fuels and chemicals. The CO2 reduction to liquid fuels by solar energy is a good attempt to introduce renewables into the existing energy and chemical infrastructures, having a higher energy density and easier transport/storage than other competing solutions （i.e. H2）.
基金supported by EU with ERC Synergy SCOPE(Surface-Confined Fast-modulated Plasma for Process and Energy Intensification in Small Molecules Conversion,810182)ProjectItalian MUR by PRIN 2017 Projects MULTI-e (Multielectron Transfer for the Conversion of Small Moleculesan Enabling Technology for the Chemical Use of Renewable Energy,20179337R7)CO_(2) ONLY (CO_(2) as Only Source of Carbons for Monomers and PolymersA Step Forwards Circular economy) Project,017WR2LRS
文摘After short introducing the crucial role of e‐fuels to meet net‐zero emissions targets,this perspective paper discusses the differences between reactive catalysis(electro‐,photo‐and plasma‐catalysis,with focus on the first for conciseness)and thermal catalysis used at most.The main point is to evidence that to progress in producing e‐fuels,the gap is not in terms of scaling‐up and pilot testing,but rather in the fundamental needs to turn the current approach and methodologies to develop reactive catalysis,including from a mechanistic perspective,to go beyond the current methods largely derived from thermal catalysis.Developing thus new fundamental bases to understand reactive catalysis is the challenge to accelerate the progress in this area to enable the potential role towards a sustainable net‐zero emissions future.Some novel aspects are highlighted,but the general aim is rather to stimulate discussion in rethinking catalysis from an alternative perspective.
基金the frame of ERC Synergy SCOPE(project 810182)PRIN 2015 SMARTNESS project nr.2015K7FZLH projects which are gratefully acknowledgeda SINCHEM Grant.SINCHEM is a Joint Doctorate program selected under the Erasmus Mundus Action 1 Programme(FPA 2013-0037)。
文摘The direct electrocatalytic synthesis of ammonia from N2 and H2O by using renewable energy sources and ambient pressure/temperature operations is a breakthrough technology,which can reduce by over 90%the greenhouse gas emissions of this chemical and energy storage process.We report here an in-situ electrochemical activation method to prepare Fe2O3-CNT(iron oxide on carbon nanotubes)electrocatalysts for the direct ammonia synthesis from N2 and H2O.The in-situ electrochemical activation leads to a large increase of the ammonia formation rate and Faradaic efficiency which reach the surprising high values of 41.6μg mgcat^−1 h^−1 and 17%,respectively,for an in-situ activation of 3 h,among the highest values reported so far for non-precious metal catalysts that use a continuous-flow polymer-electrolytemembrane cell and gas-phase operations for the ammonia synthesis hemicell.The electrocatalyst was stable at least 12 h at the working conditions.Tests by switching N2 to Ar evidence that ammonia was formed from the gas-phase nitrogen.The analysis of the changes of reactivity and of the electrocatalyst characteristics as a function of the time of activation indicates a linear relationship between the ammonia formation rate and a specific XPS(X-ray-photoelectron spectroscopy)oxygen signal related to O2−in iron-oxide species.This results together with characterization data by TEM and XRD suggest that the iron species active in the direct and selective synthesis of ammonia is a maghemite-type iron oxide,and this transformation from the initial hematite is responsible for the in-situ enhancement of 3-4 times of the TOF(turnover frequency)and NH3 Faradaic efficiency.This transformation is likely related to the stabilization of the maghemite species at CNT defect sites,although for longer times of preactivation a sintering occurs with a loss of performances.
文摘The crystalline materials Ca3Sc2Si3O12 and Ca3Y2Si3O12 Were characterized by different crystal structures, as the fonmer is a cubic garnet, while the latter is an orthorhombic compound. We investigated the optical spectroscopy of these materials doped with several trivalent lanthanide ions and compared the results for the two hosts. PolycrystaUine samples were prepared by solid state reaction, both undoped and doped with the trivalent lanthanide ions Eu3＋, Tb3＋ and Sm3＋. Emission, excitation and Raman spectra of these materials were measured at temperatures ranging from 300 to 10 K. The optical spectra were assigned and discussed, and the effects of the crystal structure of the host on the spectroscopic behaviour were addressed. The technological potential of these compounds in the field of optical materials and devices was discussed,
文摘The Eu(Ⅲ)nitrate complex of the meso-N,N’-bis(2-pyridylmethylene)-1,2-(R,S)-cyclohexanediamine ligand was synthesized and characterized by single crystal and powder X-ray diffraction.The crystal lattice of the complex is capable of absorbing and desorbing selectively acetonitrile molecules,at 293 K upon an acetonitrile vapor pressure of^0.1×10^5 Pa.This process,which is partially reversible,can be easily followed by both powder X-ray diffraction(P-XRD)and Eu(III)luminescence spectroscopy.The acetonitrile molecule,located in the outer coordination sphere of the metal ion,does not affect the radiative transition probability of 5 D0 level of Eu(Ⅲ)and also it does not activate further non-radiative channels from this level.On the other hand,this molecule is capable of affecting the energy position and intensities of the crystal field components of the 5 D0→7 F2 transition.The complex in solid form can be considered a promising material for the optical sensing of acetonitrile vapors.
文摘Two families of catalysts, based on Pd nanoparticles supported on ceramic asymmetric tubular alumina membranes, are studies in the direct synthesis of H2O2. They are prepared by depositing Pd in two ways：（i） reduction with N2H4 in an ultrasonic bath and（ii） by impregnation-deposition. The first preparation leads to larger particles, with average size of around 11 nm, while the second preparation leads to smaller particles, with average size around 4 nm. The catalytic membranes were tested as prepared, after thermal treatment in air and after further pre-reduction with H2 in mild（100 ℃） conditions. Samples were characterized by TEM, CO-chemisorption monitored by DRIFTS method and TPR, while catalytic tests have been performed in a semi-batch recirculation membrane reactor. Experimental catalytic results were analysed using two kinetics models to derive the reaction constants for the parallel and consecutive reactions of the kinetic network. Smaller particles of Pd show lower selectivity due to the higher rate of parallel combustion, even if the better dispersion of Pd and thus higher metal surface area in the sample lead to a productivity in H2O2 similar or even higher than the sample with the larger Pd particles. Independently on the presence of smaller or larger Pd nanoparticles, an oxidation treatment leads to a significant enhancement in the productivity, although the catalyst progressively reduces during the catalytic process. The inhibition of the parallel combustion reaction（to water） induced from the calcination treatment remains after the in-situ reduction of the oxidized Pd species formed during the pre-treatment.This is likely due to the elimination of defect sites which dissociatively activate oxygen, and tentatively attributed to Pd sites able to give three- and four-fold coordination of CO.
文摘Novel fully biodegradable thermoplastic composite laminates reinforced with ultrathin wood laminae were prepared through a hot-pressing process by using two different thermoplastic starch(TPS)matrices.The microstructure and physical properties of the resulting unidirectional and bidirectional laminates were studied.The investigated materials presented a complex microstructure,in which the porosity of the wood laminae was almost entirely occluded by the polymer matrix.The mechanical behavior of the laminates was strongly affected by the obtained microstructure,and matrix penetration in wood pores led to biodegradable composites with elastic modulus and tensile strength higher than those of their constituents.Finally,thermal welding and thermoformability tests proved how these materials possess features typical of thermoplastic materials.
基金the PRIN10-11 projects "Mechanisms of activation of CO2for the design of new materials for energy and resource efficiency" and "Innovative processes for the conversion of algal biomass for the production of jet fuel and green diesel" for the financial support
文摘The changing energy-chemistry nexus is discussed in this perspective paper about the future of sustainable energy and chemical production to identify the priorities and open issues on which focus research and development. Topics discussed regard （i） the new sustainable energy scenario, （ii） the role of energy storage （from smart grids to chemical storage of energy）, （iii） the outlooks and role of solar （bio）refineries and solar fuels, （iv） how to integrate hio- and solar-refineries to move to new economy, （v） the role of methanol at the crossover of new energy-chemistry nexus, （vi） the role of chemistry in this new scenario, （vii） the role of nanomaterials for a sustainable energy, （viii） the use of nanocarbons to design advanced energy conversion and storage devices, and （ix） possibilities and routes to exploit solar energy and methane （shale gas）. The contribution provides a glimpse of the emerging directions and routes with some elements about their possible role in the future scenario, but does not orovide a detailed analysis of the state of the art in these directions
基金funding from the European Union’s Horizon 2020 research and innovation program under grant agreement ID 767798 (OCEAN)MIUR PRIN 2017 project CO_(2) ONLY project nr. 2017WR2LRS。
文摘Electrodes prepared by anodic oxidation of Ti foils are robust and not toxic materials for the electrocatalytic reduction of oxalic acid to glycolic acid, allowing the development of a renewable energy-driven process for producing an alcoholic compound from an organic acid at low potential and room temperature. Coupled with the electrochemical synthesis of the oxalic acid from CO_(2),this process represents a new green and low-carbon path to produce added value chemicals from CO_(2). Various electrodes prepared by anodic oxidation of Ti foils were investigated. They were characterized by the presence of a TiO_(2) nanotube array together with the presence of small patches, debris, or TiO_(2) nanoparticles. The concentration of oxygen vacancies, the amount of Ti^(3+) measured by X-ray photoelectron spectroscopy(XPS) and the intensity of the anodic peak measured by cyclic voltammetry, were positively correlated with the achieved oxalic acid conversion and glycolic acid yield. The analysis of the results indicates the presence of small amorphous TiO_(2) nanoparticles(or surface patches or debris) interacting with TiO_(2) nanotubes, the sites responsible for the conversion of oxalic acid and glycolic acid yield. By varying this structural characteristic of the electrodes, it is possible to tune the glycolic acid to glyoxylic acid relative ratio. A best cumulative Faradaic efficiency(FE) of about 84% with FE to glycolic acid around 60% and oxalic conversion about 30% was observed.
