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1.
Nature ; 629(8011): 295-306, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38720037

RESUMEN

Fossil fuels-coal, oil and gas-supply most of the world's energy and also form the basis of many products essential for everyday life. Their use is the largest contributor to the carbon dioxide emissions that drive global climate change, prompting joint efforts to find renewable alternatives that might enable a carbon-neutral society by as early as 2050. There are clear paths for renewable electricity to replace fossil-fuel-based energy, but the transport fuels and chemicals produced in oil refineries will still be needed. We can attempt to close the carbon cycle associated with their use by electrifying refinery processes and by changing the raw materials that go into a refinery from fossils fuels to carbon dioxide for making hydrocarbon fuels and to agricultural and municipal waste for making chemicals and polymers. We argue that, with sufficient long-term commitment and support, the science and technology for such a completely fossil-free refinery, delivering the products required after 2050 (less fuels, more chemicals), could be developed. This future refinery will require substantially larger areas and greater mineral resources than is the case at present and critically depends on the capacity to generate large amounts of renewable energy for hydrogen production and carbon dioxide capture.


Asunto(s)
Dióxido de Carbono , Combustibles Fósiles , Industria del Petróleo y Gas , Energía Renovable , Ciclo del Carbono , Dióxido de Carbono/efectos adversos , Dióxido de Carbono/aislamiento & purificación , Carbón Mineral/efectos adversos , Carbón Mineral/provisión & distribución , Combustibles Fósiles/efectos adversos , Combustibles Fósiles/provisión & distribución , Hidrógeno/química , Gas Natural/efectos adversos , Gas Natural/provisión & distribución , Petróleo/efectos adversos , Petróleo/provisión & distribución , Energía Renovable/estadística & datos numéricos , Industria del Petróleo y Gas/métodos , Industria del Petróleo y Gas/tendencias
2.
PLoS One ; 19(5): e0302972, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38722925

RESUMEN

Electroless nickel plating is a suitable technology for the hydrogen industry because electroless nickel can be mass-produced at a low cost. Investigating in a complex environment where hydrogen permeation and friction/wear work simultaneously is necessary to apply it to hydrogen valves for hydrogen fuel cell vehicles. In this research, the effects of hydrogen permeation on the mechanical characteristics of electroless nickel-plated free-cutting steel (SUM 24L) were investigated. Due to the inherent characteristics of electroless nickel plating, the damage (cracks and delamination of grain) and micro-particles by hydrogen permeation were clearly observed at the grain boundaries and triple junctions. In particular, the cracks grew from grain boundary toward the intergranualr. This is because the grain boundaries and triple junctions are hydrogen permeation pathways and increasing area of the hydrogen partial pressure. As a result, its surface roughness increased by a maximum of two times, and its hardness and adhesion strength decreased by hydrogen permeation. In particular, hydrogen permeation increased the friction coefficient of the electroless nickel-plated layer, and the damage caused by adhesive wear was significantly greater, increasing the wear depth by up to 5.7 times. This is believed to be due to the decreasing in wear resistance of the electroless nickel plating layer damaged by hydrogen permeation. Nevertheless, the Vickers hardness and the friction coefficient of the electroless nickel plating layer were improved by about 3 and 5.6 times, respectively, compared with those of the free-cutting steel. In particular, the electroless nickel-plated specimens with hydrogen embrittlement exhibited significantly better mechanical characteristics and wear resistance than the free-cutting steel.


Asunto(s)
Hidrógeno , Níquel , Acero , Hidrógeno/química , Níquel/química , Acero/química , Suministros de Energía Eléctrica , Propiedades de Superficie , Ensayo de Materiales
3.
J Chem Phys ; 160(18)2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38716851

RESUMEN

We studied the origin of the vibrational signatures in the sum-frequency generation (SFG) spectrum of fibrillar collagen type I in the carbon-hydrogen stretching regime. For this purpose, we developed an all-reflective, laser-scanning SFG microscope with minimum chromatic aberrations and excellent retention of the polarization state of the incident beams. We performed detailed SFG measurements of aligned collagen fibers obtained from rat tail tendon, enabling the characterization of the magnitude and polarization-orientation dependence of individual tensor elements Xijk2 of collagen's nonlinear susceptibility. Using the three-dimensional atomic positions derived from published crystallographic data of collagen type I, we simulated its Xijk2 elements for the methylene stretching vibration and compared the predicted response with the experimental results. Our analysis revealed that the carbon-hydrogen stretching range of the SFG spectrum is dominated by symmetric stretching modes of methylene bridge groups on the pyrrolidine rings of the proline and hydroxyproline residues, giving rise to a dominant peak near 2942 cm-1 and a shoulder at 2917 cm-1. Weak asymmetric stretches of the methylene bridge group of glycine are observed in the region near 2870 cm-1, whereas asymmetric CH2-stretching modes on the pyrrolidine rings are found in the 2980 to 3030 cm-1 range. These findings help predict the protein's nonlinear optical properties from its crystal structure, thus establishing a connection between the protein structure and SFG spectroscopic measurements.


Asunto(s)
Carbono , Colágeno Tipo I , Hidrógeno , Hidrógeno/química , Carbono/química , Colágeno Tipo I/química , Ratas , Animales , Análisis Espectral/métodos
4.
Eur J Med Res ; 29(1): 285, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38745325

RESUMEN

INTRODUCTION: Hydrogen (H2) is regarded as a novel therapeutic agent against several diseases owing to its inherent biosafety. Bronchopulmonary dysplasia (BPD) has been widely considered among adverse pregnancy outcomes, without effective treatment. Placenta plays a role in defense, synthesis, and immunity, which provides a new perspective for the treatment of BPD. This study aimed to investigate if H2 reduced the placental inflammation to protect the neonatal rat against BPD damage and potential mechanisms. METHODS: We induced neonatal BPD model by injecting lipopolysaccharide (LPS, 1 µg) into the amniotic fluid at embryonic day 16.5 as LPS group. LPS + H2 group inhaled 42% H2 gas (4 h/day) until the samples were collected. We primarily analyzed the neonatal outcomes and then compared inflammatory levels from the control group (CON), LPS group and LPS + H2 group. HE staining was performed to evaluate inflammatory levels. RNA sequencing revealed dominant differentially expressed genes. Bioinformatics analysis (GO and KEGG) of RNA-seq was applied to mine the signaling pathways involved in protective effect of H2 on the development of LPS-induced BPD. We further used qRT-PCR, Western blot and ELISA methods to verify differential expression of mRNA and proteins. Moreover, we verified the correlation between the upstream signaling pathways and the downstream targets in LPS-induced BPD model. RESULTS: Upon administration of H2, the inflammatory infiltration degree of the LPS-induced placenta was reduced, and infiltration significantly narrowed. Hydrogen normalized LPS-induced perturbed lung development and reduced the death ratio of the fetus and neonate. RNA-seq results revealed the importance of inflammatory response biological processes and Toll-like receptor signaling pathway in protective effect of hydrogen on BPD. The over-activated upstream signals [Toll-like receptor 4 (TLR4), nuclear factor kappa-B p65 (NF-κB p65), Caspase1 (Casp1) and NLR family pyrin domain containing 3 (NLRP3) inflammasome] in LPS placenta were attenuated by H2 inhalation. The downstream targets, inflammatory cytokines/chemokines [interleukin (IL)-6, IL-18, IL-1ß, C-C motif chemokine ligand 2 (CCL2) and C-X-C motif chemokine ligand 1 (CXCL1)], were decreased both in mRNA and protein levels by H2 inhalation in LPS-induced placentas to rescue them from BPD. Correlation analysis displayed a positive association of TLR4-mediated signaling pathway both proinflammatory cytokines and chemokines in placenta. CONCLUSION: H2 inhalation ameliorates LPS-induced BPD by inhibiting excessive inflammatory cytokines and chemokines via the TLR4-NFκB-IL6/NLRP3 signaling pathway in placenta and may be a potential therapeutic strategy for BPD.


Asunto(s)
Displasia Broncopulmonar , Hidrógeno , Inflamación , Lipopolisacáridos , FN-kappa B , Proteína con Dominio Pirina 3 de la Familia NLR , Placenta , Transducción de Señal , Receptor Toll-Like 4 , Femenino , Embarazo , Lipopolisacáridos/toxicidad , Hidrógeno/farmacología , Hidrógeno/uso terapéutico , Animales , Placenta/metabolismo , Placenta/efectos de los fármacos , Receptor Toll-Like 4/metabolismo , Receptor Toll-Like 4/genética , Transducción de Señal/efectos de los fármacos , Ratas , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , FN-kappa B/metabolismo , Inflamación/metabolismo , Inflamación/tratamiento farmacológico , Administración por Inhalación , Displasia Broncopulmonar/metabolismo , Displasia Broncopulmonar/inducido químicamente , Displasia Broncopulmonar/tratamiento farmacológico , Displasia Broncopulmonar/prevención & control , Interleucina-6/metabolismo , Interleucina-6/genética , Ratas Sprague-Dawley , Modelos Animales de Enfermedad
5.
Drug Des Devel Ther ; 18: 1399-1414, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38707612

RESUMEN

Hydrogen, which is a novel biomedical molecule, is currently the subject of extensive research involving animal experiments and in vitro cell experiments, and it is gradually being applied in clinical settings. Hydrogen has been proven to possess anti-inflammatory, selective antioxidant, and antiapoptotic effects, thus exhibiting considerable protective effects in various diseases. In recent years, several studies have provided preliminary evidence for the protective effects of hydrogen on spinal cord injury (SCI). This paper provides a comprehensive review of the potential molecular biology mechanisms of hydrogen therapy and its application in treating SCI, with an aim to better explore the medical value of hydrogen and provide new avenues for the adjuvant treatment of SCI.


Asunto(s)
Hidrógeno , Traumatismos de la Médula Espinal , Traumatismos de la Médula Espinal/tratamiento farmacológico , Traumatismos de la Médula Espinal/metabolismo , Hidrógeno/farmacología , Hidrógeno/química , Humanos , Animales , Antioxidantes/farmacología , Antioxidantes/química , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/química , Apoptosis/efectos de los fármacos , Antiinflamatorios/farmacología , Antiinflamatorios/química
6.
Sci Rep ; 14(1): 11068, 2024 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-38744892

RESUMEN

Colombia's continuous contamination of water resources and the low alternatives to produce biofuels have affected the fulfillment of the objectives of sustainable development, deteriorating the environment and affecting the economic productivity of this country. Due to this reality, projects on environmental and economic sustainability, phytoremediation, and the production of biofuels such as ethanol and hydrogen were combined. The objective of this article was to design and develop a sustainable system for wastewater treatment and the generation of biofuels based on the biomass of the aquatic plant Eichhornia crassipes. A system that simulates an artificial wetland with live E. crassipes plants was designed and developed, removing organic matter contaminants; subsequently, and continuing the sustainability project, bioreactors were designed, adapted, and started up to produce bioethanol and biohydrogen with the hydrolyzed biomass used in the phytoremediation process, generating around 12 g/L of bioethanol and around 81 ml H2/g. The proposed research strategy suggests combining two sustainable methods, bioremediation and biofuel production, to preserve the natural beauty of water systems and their surroundings.


Asunto(s)
Biodegradación Ambiental , Biocombustibles , Biomasa , Eichhornia , Aguas Residuales , Eichhornia/metabolismo , Aguas Residuales/química , Purificación del Agua/métodos , Etanol/metabolismo , Reactores Biológicos , Hidrógeno/metabolismo
7.
Sci Rep ; 14(1): 10959, 2024 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-38745034

RESUMEN

Molecular hydrogen is an emerging broad-spectrum antioxidant molecule that can be used to treat myocardial infarction (MI). However, with hydrogen inhalation, the concentration that can be reached within target organs is low and the duration of action is short, which makes it difficult to achieve high dose targeted delivery of hydrogen to the heart, seriously limiting the therapeutic potential of hydrogen for MI. As a result of reactions with the internal environment of the body, subcutaneous implantation of magnesium slices leads to continuous endogenous hydrogen production, leading to a higher hydrogen concentration and a longer duration of action in target organs. In this study, we propose magnesium implant-based hydrogen therapy for MI. After subcutaneous implantation of magnesium slices in the dorsum of rats, we measured hydrogen production and efficiency, and evaluated the safety of this approach. Compared with hydrogen inhalation, it significantly improved cardiac function in rats with MI. Magnesium implantation also cleared free radicals that were released as a result of mitochondrial dysfunction, as well as suppressing cardiomyocyte apoptosis.


Asunto(s)
Hidrógeno , Magnesio , Infarto del Miocardio , Animales , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/metabolismo , Magnesio/metabolismo , Ratas , Masculino , Ratas Sprague-Dawley , Apoptosis/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/efectos de los fármacos , Modelos Animales de Enfermedad
8.
J Am Chem Soc ; 146(19): 13488-13498, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38709095

RESUMEN

Self-assembling peptides represent a captivating area of study in nanotechnology and biomaterials. This interest is largely driven by their unique properties and the vast application potential across various fields such as catalytic functions. However, design complexities, including high-dimensional sequence space and structural diversity, pose significant challenges in the study of such systems. In this work, we explored the possibility of self-assembled peptides to catalyze the hydrolysis of hydrosilane for hydrogen production using ab initio calculations and carried out wet-lab experiments to confirm the feasibility of these catalytic reactions under ambient conditions. Further, we delved into the nuanced interplay between sequence, structural conformation, and catalytic activity by combining modeling with experimental techniques such as transmission electron microscopy and nuclear magnetic resonance and proposed a dual mode of the microstructure of the catalytic center. Our results reveal that although research in this area is still at an early stage, the development of self-assembled peptide catalysts for hydrogen production has the potential to provide a more sustainable and efficient alternative to conventional hydrogen production methods. In addition, this work also demonstrates that a computation-driven rational design supplemented by experimental validation is an effective protocol for conducting research on functional self-assembled peptides.


Asunto(s)
Hidrógeno , Péptidos , Hidrógeno/química , Catálisis , Péptidos/química , Modelos Moleculares , Hidrólisis
9.
Ter Arkh ; 96(3): 260-265, 2024 Apr 16.
Artículo en Ruso | MEDLINE | ID: mdl-38713041

RESUMEN

Рost-COVID-19 syndrome (PS) is one of the medical and social problem. According to WHO, 10-20% of COVID-19 patients suffer from PS. The use of medical gases - inhaled nitric oxide (iNO) and molecular hydrogen (iH2) - may influence on the mechanisms of development PC. AIM: To evaluate the safety and efficacy of the combined inhalation of NO and H2 (iNO/iH2) in patients with respiratory manifestations of PS. MATERIALS AND METHODS: 34 patients with PS (11 men/23 women, 60.0±11.7 years) were included in the prospective open-label controlled study in parallel groups: the main group (n=17) received iNO/iH2 for 90 minutes once a day for 10 days (concentration of NO 60 ppm, H2<4% in the gas mixture), the control group (n=17) didn't receive inhalations. The period from the confirmation of COVID-19 to the start of the study was 641.8±230.5 days. The groups did not differ in the baseline parameters. The clinical symptoms (from the self-observation diary and mMRC questionnaires, "dyspnea language"), FAS, HADS, SF-36 scores, 6-minute walk test, the blood serum parameters of oxidative stress, the dynamics of the microcirculation in the eye bulbar conjunctiva were evaluated. The individual dose of iNO has chosen during a 15-minute test (the positive dynamics of the microcirculation have indicated that the dose was selected correctly). RESULTS: The decrease the symptoms severity, such as dyspnea, cough, fatigue and palpitations (p<0.005), the increase in SF-36 questionnaire scores (p=0.006) and a reducing of FAS score (p=0.001), as well as the anxiety component of HADS (p=0.02) were revealed at the end of treatment in the main group compared to the control group. We observed an improvement in distance walked (p=0.01) and the values SpO2 (p=0.04) in 6-minute walk test, the increase in the volumetric blood flow velocity in venules (p<0.001), and the date in oxidative damage (p<0.001) and antioxidant activity (p=0.03) parameters in the blood serum. CONCLUSION: The results of the study demonstrate clinical efficacy iNO/iH2 on clinical indicators, parameters of oxidative stress and microcirculation in patients with PS.


Asunto(s)
COVID-19 , Hidrógeno , Óxido Nítrico , Humanos , Femenino , Masculino , Óxido Nítrico/administración & dosificación , COVID-19/complicaciones , Hidrógeno/administración & dosificación , Persona de Mediana Edad , Administración por Inhalación , Estudios Prospectivos , SARS-CoV-2 , Síndrome Post Agudo de COVID-19 , Resultado del Tratamiento , Anciano
10.
Nat Commun ; 15(1): 3708, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38714662

RESUMEN

Cheminformatics-based machine learning (ML) has been employed to determine optimal reaction conditions, including catalyst structures, in the field of synthetic chemistry. However, such ML-focused strategies have remained largely unexplored in the context of catalytic molecular transformations using Lewis-acidic main-group elements, probably due to the absence of a candidate library and effective guidelines (parameters) for the prediction of the activity of main-group elements. Here, the construction of a triarylborane library and its application to an ML-assisted approach for the catalytic reductive alkylation of aniline-derived amino acids and C-terminal-protected peptides with aldehydes and H2 is reported. A combined theoretical and experimental approach identified the optimal borane, i.e., B(2,3,5,6-Cl4-C6H)(2,6-F2-3,5-(CF3)2-C6H)2, which exhibits remarkable functional-group compatibility toward aniline derivatives in the presence of 4-methyltetrahydropyran. The present catalytic system generates H2O as the sole byproduct.


Asunto(s)
Aminoácidos , Compuestos de Anilina , Boranos , Péptidos , Compuestos de Anilina/química , Catálisis , Aminoácidos/química , Péptidos/química , Boranos/química , Hidrógeno/química , Simulación por Computador , Oxidación-Reducción , Alquilación , Aprendizaje Automático
11.
Microb Cell Fact ; 23(1): 125, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38698392

RESUMEN

BACKGROUND: The facultatively anaerobic thermophile Parageobacillus thermoglucosidasius is able to produce hydrogen gas (H2) through the water-gas shift (WGS) reaction. To date this process has been evaluated under controlled conditions, with gas feedstocks comprising carbon monoxide and variable proportions of air, nitrogen and hydrogen. Ultimately, an economically viable hydrogenogenic system would make use of industrial waste/synthesis gases that contain high levels of carbon monoxide, but which may also contain contaminants such as H2, oxygen (O2) and other impurities, which may be toxic to P. thermoglucosidasius. RESULTS: We evaluated the effects of synthesis gas (syngas) mimetic feedstocks on WGS reaction-driven H2 gas production by P. thermoglucosidasius DSM 6285 in small-scale fermentations. Improved H2 gas production yields and faster onset towards hydrogen production were observed when anaerobic synthetic syngas feedstocks were used, at the expense of biomass accumulation. Furthermore, as the WGS reaction is an anoxygenic process, we evaluated the influence of O2 perturbation on P. thermoglucosidasius hydrogenogenesis. O2 supplementation improved biomass accumulation, but reduced hydrogen yields in accordance with the level of oxygen supplied. However, H2 gas production was observed at low O2 levels. Supplementation also induced rapid acetate consumption, likely to sustain growth. CONCLUSION: The utilisation of anaerobic syngas mimetic gas feedstocks to produce H2 and the relative flexibility of the P. thermoglucosidasius WGS reaction system following O2 perturbation further supports its applicability towards more robust and continuous hydrogenogenic operation.


Asunto(s)
Fermentación , Hidrógeno , Oxígeno , Hidrógeno/metabolismo , Oxígeno/metabolismo , Monóxido de Carbono/metabolismo , Anaerobiosis , Biomasa , Gases/metabolismo
12.
Bioresour Technol ; 401: 130705, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38631655

RESUMEN

A novel 70 L composite tubular photo-bioreactor was constructed, and its photo-fermentation hydrogen production characteristics of batch and continuous modes were investigated with glucose as the substrate in an outdoor environment. In the batch fermentation stage, the hydrogen production rate peaked at 37.6 mL H2/(L·h) accompanied by a high hydrogen yield of 7 mol H2/mol glucose. The daytime light conversion efficiency is 4 %, with 37 % of light energy from the sun. An optimal hydraulic retention time of 5 d was identified during continuous photo-fermentation. Under this condition, the stability of the cell concentration is maintained and more electrons can be driven to the hydrogen generation pathway while attaining a hydrogen production rate of 20.7 ± 0.9 mL H2/(L·h). The changes of biomass, volatile fatty acids concentration and ion concentration during fermentation were analyzed. Continuous hydrogen production by composite tubular photo-bioreactor offers new ideas for the large-scale deployment of photobiological hydrogen production.


Asunto(s)
Reactores Biológicos , Fermentación , Hidrógeno , Hidrógeno/metabolismo , Biomasa , Glucosa/metabolismo , Proyectos Piloto , Ácidos Grasos Volátiles/metabolismo , Luz , Técnicas de Cultivo Celular por Lotes , Fotobiorreactores , Concentración de Iones de Hidrógeno
13.
Bioresour Technol ; 401: 130733, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38670287

RESUMEN

This study investigated the mediating effect of Triethanolamine on Fe@C-Rhodobacter sphaeroides hybrid photosynthetic system to achieve efficient biohydrogen production. The biocompatible Fe@C generates excited electrons upon exposure to light, releasing ferrum for nitrogenase synthesis, and regulating the pH of the fermentation environment. Triethanolamine was introduced to optimize the electron transfer chain, thereby improving system stability, prolonging electron lifespan, and facilitating ferrum corrosion. This, in turn, stimulated the lactic acid synthetic metabolic pathway of Rhodobacter sphaeroides, resulting in increased reducing power in the biohybrid system. The ternary coupling system was analyzed through the regulation of concentration, initial pH, and light intensity. The system achieved the highest total H2 production of 5410.9 mL/L, 1.29 times higher than the control (2360.5 mL/L). This research provides a valuable strategy for constructing ferrum-carbon-based composite-cellular biohybrid systems for photo-fermentation H2 production.


Asunto(s)
Etanolaminas , Hidrógeno , Luz , Rhodobacter sphaeroides , Rhodobacter sphaeroides/metabolismo , Hidrógeno/metabolismo , Etanolaminas/metabolismo , Etanolaminas/química , Hierro/química , Catálisis , Concentración de Iones de Hidrógeno , Carbono , Fermentación , Fotosíntesis
14.
Chemosphere ; 357: 141944, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38614402

RESUMEN

Photoelectrocatalysis stands as an exceptionally efficient and sustainable method, significantly addressing both energy scarcity and environmental pollution challenges. Within this realm, quantum dots (QDs) have garnered immense attention for their outstanding catalytic properties. Their unique features-cost-effectiveness, high efficiency, remarkable stability, and exceptional photovoltaic characteristics-set them apart from other tunable semiconductor materials. Heterojunction structures based on quantum dots remarkably boost solar energy conversion efficiency. This review aims to provide a comprehensive overview of the impacts generated by heterojunctions formed using diverse quantum dots and delve into their catalytic applications. Moreover, it sheds light on recent advancements utilizing quantum dots in modifying optoelectronic semiconductor materials for diverse purposes, ranging from hydrogen (H2) generation to carbon and nitrogen reduction, as well as pollutant degradation. Additionally, the paper offers valuable insights into challenges faced by quantum dot applications and outlines promising future prospects.


Asunto(s)
Puntos Cuánticos , Puntos Cuánticos/química , Catálisis , Semiconductores , Hidrógeno/química , Energía Solar , Nitrógeno/química , Carbono/química
15.
Chemosphere ; 357: 142033, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38615961

RESUMEN

The design and preparation of dual-functional photocatalysts for simultaneously realizing photocatalytic wastewater purification and hydrogen energy generation pose significant challenges. This article presents the engineering of a binary heterostructured photocatalyst by combining TiO2 (nanorods) and MoS2 nanosphere using a straightforward solvothermal method and the assessment of the phase structures, morphologies, and optical properties of the resulting nanocomposites using diverse analytical techniques. The TiO2(Rod)/MoS2 composite exhibits remarkable efficacy in degrading ciprofloxacin, achieving 93% removal rate within 1 h, which is four times higher than that of bare TiO2. Moreover, the optimized TiO2(Rod)/MoS2 presents an outstanding hydrogen production rate of 7415 µmol g-1, which is ∼24 times higher than that of pristine TiO2. Under UV-visible light irradiation, the TiO2(Rod)/MoS2 heterojunction displays an exceptional photocatalytic performance in terms of both photodegradation and hydrogen production, surpassing the performance of TiO2 particle/MoS2. The study findings demonstrate that TiO2(Rod)/MoS2 nanocomposites exhibit considerably improved photocatalytic degradation and hydrogen generation activities. Based on the experimental results, a possible mechanism is proposed for the transfer and separation of charge carriers in Z-scheme heterojunctions.


Asunto(s)
Antibacterianos , Disulfuros , Hidrógeno , Molibdeno , Nanosferas , Nanotubos , Titanio , Titanio/química , Molibdeno/química , Catálisis , Antibacterianos/química , Nanosferas/química , Hidrógeno/química , Disulfuros/química , Nanotubos/química , Nanocompuestos/química , Fotólisis , Contaminantes Químicos del Agua/química , Aguas Residuales/química , Ciprofloxacina/química
17.
Nat Commun ; 15(1): 3349, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38637496

RESUMEN

Catalysed C-H activation has emerged as a transformative platform for molecular synthesis and provides new opportunities in drug discovery by late-stage functionalisation (LSF) of complex molecules. Notably, small aliphatic motifs have gained significant interest in medicinal chemistry for their beneficial properties and applications as sp3-rich functional group bioisosteres. In this context, we disclose a versatile strategy with broad applicability for the ruthenium-catalysed late-stage meta-C(sp2)-H alkylation of pharmaceuticals. This general protocol leverages numerous directing groups inherently part of bioactive scaffolds to selectivity install a variety of medicinally relevant bifunctional alkyl units within drug compounds. Our strategy enables the direct modification of unprotected lead structures to quickly generate an array of pharmaceutically useful analogues without resorting to de novo syntheses. Moreover, productive late-stage modulation of key biological characteristics of drug candidates upon remote C-H alkylation proves viable, highlighting the major benefits of our approach to offer in drug development programmes.


Asunto(s)
Hidrógeno , Rutenio , Hidrógeno/química , Alquilación , Rutenio/química , Catálisis , Preparaciones Farmacéuticas
18.
ACS Nano ; 18(16): 10840-10849, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38616401

RESUMEN

External electric field has the potential to influence metabolic processes such as biological hydrogen production in microorganisms. Based on this concept, we designed and constructed an electroactive hybrid system for microbial biohydrogen production under an electric field comprised of polydopamine (PDA)-modified Escherichia coli (E. coli) and Ni foam (NF). In this system, electrons generated from NF directly migrate into E. coli cells to promote highly efficient biocatalytic hydrogen production. Compared to that generated in the absence of electric field stimulation, biohydrogen production by the PDA-modified E. coli-based system is significantly enhanced. This investigation has demonstrated the mechanism for electron transfer in a biohybrid system and gives insight into precise basis for the enhancement of hydrogen production by using the multifield coupling technology.


Asunto(s)
Electrones , Escherichia coli , Hidrógeno , Polímeros , Escherichia coli/metabolismo , Hidrógeno/metabolismo , Hidrógeno/química , Polímeros/química , Polímeros/metabolismo , Indoles/química , Indoles/metabolismo , Níquel/química , Níquel/metabolismo , Transporte de Electrón
19.
J Hazard Mater ; 470: 134195, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38581872

RESUMEN

This study leveraged synthesis gas (syngas), a renewable resource attainable through the gasification of biowaste, to achieve efficient chromate removal from water. To enhance syngas transfer efficiency, a membrane biofilm reactor (MBfR) was employed. Long-term reactor operation showed a stable and high-level chromate removal efficiency > 95%, yielding harmless Cr(III) precipitates, as visualised by scanning electron microscopy and energy dispersive X-ray analysis. Corresponding to the short hydraulic retention time of 0.25 days, a high chromate removal rate of 80 µmol/L/d was attained. In addition to chromate reduction, in situ production of volatile fatty acids (VFAs) by gas fermentation was observed. Three sets of in situ batch tests and two groups of ex situ batch tests jointly unravelled the mechanisms, showing that biological chromate reduction was primarily driven by VFAs produced from in situ syngas fermentation, whereas hydrogen originally present in the syngas played a minor role. 16 S rRNA gene amplicon sequencing has confirmed the enrichment of syngas-fermenting bacteria (such as Sporomusa), who performed in situ gas fermentation leading to the synthesis of VFAs, and organics-utilising bacteria (such as Aquitalea), who utilised VFAs to drive chromate reduction. These findings, combined with batch assays, elucidate the pathways orchestrating synergistic interactions between fermentative microbial cohorts and chromate-reducing microorganisms. The findings facilitate the development of cost-effective strategies for groundwater and drinking water remediation and present an alternative application scenario for syngas.


Asunto(s)
Biopelículas , Reactores Biológicos , Cromatos , Membranas Artificiales , Cromatos/metabolismo , Fermentación , Contaminantes Químicos del Agua/metabolismo , Oxidación-Reducción , Ácidos Grasos Volátiles/metabolismo , Bacterias/metabolismo , Bacterias/genética , Hidrógeno/metabolismo , Gases/metabolismo , Biodegradación Ambiental
20.
Chemosphere ; 356: 141929, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38604520

RESUMEN

The cleaning and utilization of industry wastewater are still a big challenge. In this work, we mainly investigate the effect of electron transfer among multi-interfaces on water electrolysis reaction. Typically, the CoS2, Co3S4/CoS2 (designated as CS4-2) and Co3S4/Co9S8/CoS2 (designated as CS4-8-2) samples are prepared on a large scale by one-step molten salt method. It is found that because of the different work functions (designated as WF; WF(Co3S4) = 4.48eV, WF(CoS2) = 4.41eV, WF(Co9S8) = 4.18 eV), the effective heterojunctions at the multi-interfaces of CS4-8-2 sample, which obviously improve interface charge transfer. Thus, the CS4-8-2 sample shows an excellent oxygen evolution reaction (OER) activity (134 mV/10 mA cm-2, 40 mV dec-1). The larger double-layer capacitance (Cdl = 17.1 mF cm-2) of the CS4-8-2 sample indicates more electrochemical active sites, compared to the CoS2 and CS4-2 samples. Density functional theory (DFT) calculation proves that due to interface polarization under electric field, the multi-interfaces effectively promote electron transfer and regulate electron structure, thus promoting the adsorption of OH- and dissociation of H2O. Moreover, an innovative norfloxacin (NFX) electrolytic cell (EC) is developed through introducing NFX into the electrolyte, in which efficient NFX degradation and hydrogen production are synergistically achieved. To reach 50 mA cm-2, the required cell voltage of NFX-EC has decreased by 35.2%, compared to conventional KOH-EC. After 2h running at 1 V, 25.5% NFX was degraded in the NFX EC. This innovative NFX-EC is highly energy-efficient, which is promising for the synergistic cleaning and utilization of industry wastewater.


Asunto(s)
Electrólisis , Hidrógeno , Aguas Residuales , Agua , Hidrógeno/química , Aguas Residuales/química , Agua/química , Transporte de Electrón , Contaminantes Químicos del Agua/química , Eliminación de Residuos Líquidos/métodos , Oxígeno/química , Electrones
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