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Developing high-performance Pt-based catalysts with low Pt loading is crucial but challenging for CO oxidation at temperatures below 100 °C. Herein, we report a Pt-based catalyst with only a 0.15 wt% Pt loading, which consists of Pt-Ti intermetallic single-atom alloy (ISAA) and Pt nanoparticles (NP) co-supported on a defective TiO2 support, achieving a record high turnover frequency of 11.59 s-1 at 80 °C and complete conversion of CO at 120 °C. This is because the coexistence of Pt-Ti ISAA and Pt NP significantly alleviates the competitive adsorption of CO and O2, enhancing the activation of O2. Furthermore, Pt single atom sites are stabilized by Pt-Ti ISAA, resulting in distortion of the TiO2 lattice within Pt-Ti ISAA. This distortion activates the neighboring surface lattice oxygen, allowing for the simultaneous occurrence of the Mars-van Krevelen and Langmuir-Hinshelwood reaction paths at low temperatures.
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Understanding the reconstruction mechanism to rationally design cost-effective electrocatalysts for oxygen evolution reaction (OER) is still challenging. Herein, a defect-rich NiMoO4 precatalyst is used to explore its OER activity and reconstruction mechanism. In situ generated oxygen vacancies, distorted lattices, and edge dislocations expedite the deep reconstruction of NiMoO4 to form polycrystalline Ni (oxy)hydroxides for alkaline oxygen evolution. It only needs ≈230 and ≈285 mV to reach 10 and 100 mA cm-2, respectively. The reconstruction boosted by the redox of Ni is confirmed experimentally by sectionalized cyclic voltammetry activations at different specified potential ranges combined with ex situ characterization techniques. Subsequently, the reconstruction route is presented based on the acid-base electronic theory. Accordingly, the dominant contribution of the adsorbate evolution mechanism to reconstruction during oxygen evolution is revealed. This work develops a novel route to synthesize defect-rich materials and provides new tactics to investigate the reconstruction.
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Constructing an environmentally friendly and efficient electrocatalyst holds important and profound significance for energy-efficient hydrogen production. Replacing the oxygen evolution reaction with a lower potential urea oxidation reaction (UOR) may save energy in water electrolysis to produce hydrogen. The UOR is characterized by its high energy barrier, which results in slow reaction kinetics. In this study, we introduced Ba(OH)2 into Ni(OH)2 to form uniform nanosheets. Due to the introduction of Ba2+, the lattice expansion of Ni(OH)2 was triggered, leading to significant improvement in UOR activity. The catalyst achieved a current density of 100 mA cm-2 at only 1.316 V and exhibited remarkable stability over time. Density functional theory (DFT) calculations demonstrate that the Ba-Ni(OH)2 site significantly reduces the energy barrier for urea adsorption, intermediate steps, and desorption. This work provides a novel and environmentally friendly strategy for constructing energy-efficient and highly efficient catalysts through the doping of alkaline earth metals.
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Senescence-induced therapy was previously considered as an effective treatment for tumors, and cellular senescence was initially regarded as an effective mechanism against cancer. However, whether cell senescence-related genes can be used to predict the prognosis of papillary thyroid carcinoma (PTC) and immunotherapy remains unclear. We developed and validated a cell senescence-related signature (CSRS) by analyzing the gene expression of 278 genes related to cellular senescence in 738 patients with PTC. Additionally, further analysis showed that CSRS was a reliable predictor of patient outcomes in combination with immune checkpoint expression and drug susceptibility, and patients with high risk scores may benefit from immunotherapy. The findings of this study demonstrate that CSRS serves as an immunotherapeutic response and prognosis biomarker affecting the tumor immune microenvironment of PTC.
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Senescencia Celular , Neoplasias de la Tiroides , Humanos , Cáncer Papilar Tiroideo/genética , Inmunoterapia , Factores de Riesgo , Microambiente Tumoral/genética , Neoplasias de la Tiroides/genética , PronósticoRESUMEN
Mesocrystals (MCs) with high-index facets may have superior catalytic properties to those with low-index facets and their nanocrystal counterparts. However, synthesizing such mesocrystal materials is still very challenging because of the metastability of MCs and energetic high-index crystal facets. This work reports a successful solvothermal method followed by calcination for synthesizing copper oxide-based MCs possessing a core-shell structure (denoted as Cu2 O@CuO HIMCs). Furthermore, these MCs are predominantly bounded by the high-index facets such as {311} or {312} with a high-density of stepped atoms. When used as catalysts in Si hydrochlorination to produce trichlorosilane (TCS, the primary feedstock of high-purity crystalline Si), Cu2 O@CuO HIMCs exhibit significantly enhanced Si conversion and TCS selectivity compared to those with flat surfaces and their nanostructured counterparts. Theoretical calculations reveal that both the core-shell structure and the high-index surface contribute to the increased electron density of Cu sites in Cu2 O@CuO HIMCs, promoting the adsorption and dissociation of HCl and stabilizing the dissociated Cl* intermediate. This work provides a simple method for synthesizing high-index faceted MCs and offers a feasible strategy to enhance the catalytic performance of MCs.
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Designing catalysts to proceed with catalytic reactions along the desired reaction pathways, e.g., CO2 methanation, has received much attention but remains a huge challenge. This work reports one Ru1Ni single-atom alloy (SAA) catalyst (Ru1Ni/SiO2) prepared via a galvanic replacement reaction between RuCl3 and Ni nanoparticles (NPs) derived from the reduction of Ni phyllosilicate (Ni-ph). Ru1Ni/SiO2 achieved much improved selectivity toward hydrogenation of CO2 to CH4 and catalytic activity (Turnover frequency (TOF) value: 40.00 × 10-3 s-1), much higher than those of Ni/SiO2 (TOF value: 4.40 × 10-3 s-1) and most reported Ni-based catalysts (TOF value: 1.03 × 10-3-11.00 × 10-3 s-1). Experimental studies verify that Ru single atoms are anchored onto the Ni NPs surface via the Ru1-Ni coordination accompanied by electron transfer from Ru1 to Ni. Both in situ experiments and theoretical calculations confirm that the interface sites of Ru1Ni-SAA are the intrinsic active sites, which promote the direct dissociation of CO2 and lower the energy barrier for the hydrogenation of CO* intermediate, thereby directing and enhancing the CO2 hydrogenation to CH4.
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Hybrid cocatalysts have great application potential for improving the photocatalytic hydrogen evolution performance of semiconductors. The interfaces between components of hybrid cocatalysts make a great contribution to the improvement, but the associated mechanisms remain unclear. Herein, we prepared and tested three comparative CdS-based photocatalysts with NiS, NiS/Ni9S8, and Ni9S8 as the cocatalysts separately. The emphasis is placed on investigating the effect of the NiS/Ni9S8 interfaces on the photocatalytic hydrogen evolution performance of CdS. NiS/Ni9S8 exhibits a higher ability than NiS and Ni9S8 in making CdS a more active photocatalyst for water splitting. It shows that NiS, NiS/Ni9S8, and Ni9S8 perform similarly in terms of promoting the charge transfer and separation of CdS based on steady-state and time-resolved photoluminescence studies. At the same time, the linear sweep voltammetry and electrochemical impedance spectroscopy tests combined with the density functional theory calculations reveal that the component interfaces of NiS/Ni9S8 enable us to lower the water splitting activation energy, the charge-transfer resistance from the cocatalyst to sacrificial agent, and hydrogen adsorption Gibbs free energy. It is evidenced from this work that component interfaces of hybrid cocatalysts play a vital role in accelerating the dynamics of hydrogen evolution reactions.
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Engineering thermochemistry is the science and technology that studies, innovates, and engineers heat-induced or heat-driven thermochemical reactions and can potentially lead to reductions of five-plus billion tons of CO2 emissions effectively and economically.
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A series of cerium-based high-entropy oxide catalysts (the ratio of CeO2 and HEO is 1:1) was prepared by a solid-state reaction method, which exploit their unique structural and performance advantages. The Ce-HEO-T samples can achieve 100% toluene conversion rate above 328°C when they were used as catalysts directly. Subsequently, the Ce-HEO-500 exhibited the lowest temperature for toluene oxidation was used as a support to deposit different amounts of Au for a further performance improvement. Among all of prepared samples, Au/Ce-HEO-500 with a moderate content of Au (0.5â wt%) exhibited the lowest temperature for complete combustion of toluene (260°C), which decreased nearly 70°C compared with Ce-HEO-500 support. Moreover, it also showed excellent stability for 60â h with 98% toluene conversion rate. Most importantly, under the condition of 5â vol.% H2O vapour, the toluene conversion rate remained unchanged and even increased slightly compared with that in dry air, exhibiting excellent water resistance. Combined with the characterizations of XRD, SEM, TEM, BET, Raman, H2-TPR and XPS, it was found that the high dispersion of active Au NPs, the special high-entropy structure and the synergistic effect between Au and Ce, Co, Cu are the key factors when improving the catalytic performance in the Au/Ce-HEO-500 catalyst.
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For the first time, a nanosheet-state CoMnx mixed oxide with multifarious active regions was synthesized by oxidation-etching assembly of metal organic framework (MOF) precursor and applied for catalytic combustion of toluene at low temperatures. The obtained optimum catalyst denoted as CoMn6 showed excellent performance, which achieved 90% conversion of 1,000 ppm toluene under a weight hourly space velocity (WHSV) of 60,000 mL/(g·h) at 219 °C. While, it also exhibited long-term stability with strong water resistance property. The characterizations of physicochemical properties indicated that the oxidation-etching assembly process built an abundant mesoporous structure in the CoMnx catalyst, which greatly increased the specific surface area (SSA). Especially, potassium permanganate as oxidant and manganese source led to uniform dispersion and assembling of cobalt atoms, which caused the generation of low-crystallinity CoMnx mixed oxide with abundant dislocations, vacancies, phase interfaces and amorphous structures, resulting in excellent low-temperature reducibility, outstanding lattice oxygen mobility and abundant active species such as Mn3+, Co3+ and adsorbed oxygen species. Density functional theory (DFT) calculations demonstrated that gaseous oxygen with the longer bond length (1.406 Å) and stronger adsorption energy (-4.443 eV) could be adsorbed and activated well on the MnCo2O4.5 (311) plane, which is beneficial for the toluene oxidation. In situ diffuse reflectance infrared spectroscopy (DRIFTS) technique was applied to track the intermediates of toluene combustion under different atmospheres, which further deduced the contributions of different active regions and oxidation mechanism over the CoMnx catalyst. The present facile strategy of oxidation-etching assembly of the MOF precursor for the creating of novel catalyst with high performance could be applied in a wide variety of materials besides VOC combustion catalysts.
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Objective: The aim of this study was to evaluate the effect of sequential pulmonary resections by uniportal video-assisted thoracoscopic surgery (VATS) for bilateral multiple pulmonary nodules (BMPNs). Methods: A single-center, prospective, nonrandomized study was performed on patients who underwent one-stage or two-stage operations by uniportal VATS. The clinical, pathological and perioperative data were summarized and analyzed from January 2021 to December 2021. Results: A total of 80 patients were included during the study period. Sequential pulmonary resection by uniportal VATS was underwent in 40 patients. There were no perioperative deaths and serious complications, 2 patients had postoperative pneumonia, 3 patients had transient atrial fibrillation, 1 patient had persistent severe air leakage, 1 patient occurred hemoptysis. The one-stage group had less operative time, surgical blood loss, pleural drainage, chest tube duration and postoperative admission duration(P<0.05). The results of pathological examination of pulmonary nodules revealed adenocarcinoma in situ (n=12), minimally invasive adenocarcinoma (n=24), invasive adenocarcinoma (n=42), squamous carcinoma (n=1),and benign nodules (n=10). The pathological diagnosis included multiple primary lung cancers (30/40, 75%), single primary lung cancer (6/40, 15%). The most advanced pathologic stage of the primary lung cancer was classified as IA (n=19), IB (n=5), II (n=3), and IIIA (n=2). Conclusion: For patients with excellent pulmonary function, sequential pulmonary resection by uniportal VATS is a safe and feasible for BMPNs. Strict control of surgical indications, reasonable preoperative planning, accurate intraoperative operation, and standardized perioperative management can effectively reduce complications and maximize benefits for suitable patients.
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The lack of efficient catalysts with a wide working temperature window and vital O2 and SO2 resistance for selective catalytic reduction of NO by CO (CO-SCR) largely hinders its implementation. Here, a novel Ir-based catalyst with only 1 wt% Ir loading is reported for efficient CO-SCR. In this catalyst, contiguous Ir atoms are isolated into single atoms, and Ir-W intermetallic nanoparticles are formed, which are supported on ordered mesoporous SiO2 (KIT-6). Notably, this catalyst enables complete NO conversion to N2 at 250 °C in the presence of 1% O2 and has a wide temperature window (250-400 °C), outperforming the comparison samples with Ir isolated-single-atomic-sites and Ir nanoparticles, respectively. Also, it possesses a high SO2 tolerance. Both experimental results and theoretical calculations reveal that single Ir atoms are negatively charged, dramatically enhancing the NO dissociation, while the Ir-W intermetallic nanoparticles accelerate the reduction of the N2 O and NO2 intermediates by CO.
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Tuning the electronic structures of mesocrystals at the atomic level is an effective approach to obtaining unprecedented properties. Here, a lattice-confined strategy to obtain isolated single-site Sn atoms in CuO mesocrystals to improve catalytic performance is reported. The Sn/CuO mesocrystal composite (Sn/CuO MC) has ordered Sn-O-Cu atomic interfaces originated from the long-range ordering of the CuO mesocrystal itself. X-ray absorption fine structure measurements confirm that the positively charged Sn atoms can tune the electronic structure of the Cu atoms to some extent in Sn/CuO MC, quite different from that in the conventional single-atom Sn-modified CuO nanoparticles and nanoparticulate SnO2 -modified CuO mesocrystal catalysts. When tested for the Si hydrochlorination reaction to produce trichlorosilane, Sn/CuO MC exhibits significantly better performances than the above two catalysts. Theoretical calculations further reveal the electronic modification to the active Cu component and the induced improvement in HCl adsorption, and thus enhance the catalytic performance. This work demonstrates how to design efficient metal oxide mesocrystal catalysts through an electronic structure modification approach.
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Electronic skin (e-skin), a new generation of flexible electronics, has drawn interest in soft robotics, artificial intelligence, and biomedical devices. However, most existing e-skins involve complex preparation procedures and are characterized by single-sensing capability and insufficient scalability. Here, we report on a one-step strategy in which a thermionic source is used for the in situ molecularization of bacterial cellulose polymeric fibers into molecular chains, controllably constructing an ionogel with a scalable mode for e-skin. The synergistic effect of a molecular-scale hydrogen bond interweaving network and a nanoscale fiber skeleton confers a robust tensile strength (up to 7.8 MPa) and high ionic conductivity (up to 62.58 mS/cm) on the as-developed ionogel. Inspired by the tongue to engineer the perceptual patterns in this ionogel, we present a smart e-skin with the perfect combination of excellent ion transport and discriminability, showing six stimulating responses to pressure, touch, temperature, humidity, magnetic force, and even astringency. This study proposes a simple, efficient, controllable, and sustainable approach toward a low-carbon, versatile, and scalable e-skin design and structure-performance development.
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With the forthcoming of the post-COVID-19 and the ageing era, the novel biomaterials and bioelectronic devices are attracting more and more attention and favor. Cellulose as one of the most globe-abundant natural macromolecules has multiple merits of biocompatibility, processability, carbon neutral feature and mechanical designability. Due to its progressive advancement of multi-scale design from macro to micro followed by new cognitions, cellulose shows a promising application prospect in developing bio-functional materials. In this review, we briefly discuss the role of cellulose from the "top-down" perspective of macro-scale fibers, micro-scale nanofibers, and molecular-scale macromolecular chains for the design of advanced cellulose-based functional materials. The focus then turns to the construction and development of emerging cellulose-based flexible bioelectronic devices including biosensors, biomimetic electronic skins, and biological detection devices. Finally, the dilemma and challenge of cellulose-based bioelectronic materials and their application prospects in basic biology and medical care have been prospected.
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Materiales Biocompatibles , Técnicas Biosensibles , Celulosa , Dispositivos Electrónicos Vestibles , Nanofibras/químicaRESUMEN
In nature, stiffness-changing behavior is essential for living organisms, which, however, is challenging to achieve in synthetic materials. Here, a stiffness-changing smart material, through developing interchangeable supramolecular configurations inspired from the dermis of the sea cucumber, which shows extreme, switchable mechanical properties, is reported. In the hydrated state, the material, possessing a stretched, double-stranded supramolecular network, showcases a soft-gel behavior with a low stiffness and high pliability. Upon the stimulation of ethanol to transform into the coiled supramolecular configuration, it self-adjusts to a hard state with nearly 500-times enhanced stiffness from 0.51 to 243.6 MPa, outstanding load-bearing capability (over 35 000 times its own weight), and excellent puncture/impact resistance with a specific impact strength of ≈116 kJ m-2 (g cm-3 )-1 (higher than some metals and alloys such as aluminum, and even comparable to the commercially available protective materials such as D3O and Kevlar). Moreover, this material demonstrates reconfiguration-dependent self-healing behavior and designable formability, holding great promise in advanced engineering fields that require both high-strength durability and good formability. This work may open up a new perspective for the development of self-regulating materials from supramolecular-scale configuration regulation.
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The activities of various MgO catalysts, which were prepared from different methods such as hydration synthesis, thermal decomposition, combustion, sol-gel and co-precipitation, were conducted in dimethyl carbonate (DMC) synthesis via transesterification of ethylene carbonate with methanol. MgO-P-Na2CO3-3.14 synthesized by the excess Na2CO3 precipitation compared the best catalytic activity and stability, which could be reused for seven times without obvious deactivation. The DMC yield was as high as 69.97% at 68 °C. The transesterification reaction could be separated into two steps, and the samples obtained by NaOH precipitant exhibited better ring-opening capability, while the catalysts acquired by Na2CO3 precipitant displayed superior transesterification ability. The structure-performance relationship was evaluated by multiple characterization methods. The results indicated that the as-synthesized catalyst derived from dried precursors with more crystalline magnesium carbonate was favorable for the promotion of DMC yield, and MgO-P-Na2CO3-3.14 with more Mg-O pairs, which were the active center for the transesterification of 2-hydroxyethyl methyl carbonate (HEMC) intermediate with methanol, resulted in more moderately basic sites left that was in accordance with the DMC yield variation. MgO-P-Na2CO3-3.14 with greater BET surface area and mesopore volume, relative low surface oxygen content and larger moderately basic sites amount compared the excellent activity in DMC synthesis.
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Due to their high biocompatibility, high spatial resolution, chromatographic capability, and adjustable size and morphology, magnetic nanoparticles have become the most promising nanomaterials for clinical application in noninvasive imaging and drug delivery for the treatment of malignant tumors. Herein, a novel magnetic nanoparticle coated with calcium carbonate was prepared and loaded with near-infrared drugs to be used as a multifunctional theranostic nanoplatform for the diagnosis and treatment of malignant tumors. Then, these drug-loaded nanoparticles were used for combined photodynamic/photothermal therapy by intravenous administration that was simultaneously guided by fluorescence/MR imaging. Due to the targeted induction of the external magnetic field and tumor response degradation of the calcium carbonate layer, the nanoprobe demonstrated excellent tumor targeting and greatly improved drug aggregation at the tumor site. Finally, single wavelength-mediated photothermal/photodynamic therapy was applied to liver cancer model mice, ultimately achieving an exciting antitumor therapeutic effect. This study may promote further exploration of nanoplatforms based on magnetic nanoparticles for clinical application in the treatment of malignant tumors.
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Antineoplásicos/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas de Magnetita/administración & dosificación , Fármacos Fotosensibilizantes/administración & dosificación , Animales , Antineoplásicos/química , Antineoplásicos/farmacocinética , Carbonato de Calcio/administración & dosificación , Carbonato de Calcio/química , Línea Celular Tumoral , Liberación de Fármacos , Humanos , Verde de Indocianina/administración & dosificación , Verde de Indocianina/análogos & derivados , Verde de Indocianina/química , Verde de Indocianina/farmacocinética , Rayos Infrarrojos , Imagen por Resonancia Magnética , Nanopartículas de Magnetita/química , Ratones , Neoplasias/diagnóstico por imagen , Neoplasias/tratamiento farmacológico , Imagen Óptica , Fotoquimioterapia , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacocinética , Terapia Fototérmica , Nanomedicina TeranósticaRESUMEN
BACKGROUND: The aim of this study was to evaluate the effect of uniportal and three-portal VATS in lung cancer patients on the postoperative short-term quality of life (QOL). METHODS: A single-center, prospective, nonrandomized study was performed on patients who underwent uniportal or three-portal video-assisted thoracoscopic surgery (VATS) lobectomy and systemic mediastinal lymph node dissection. QOL was measured before surgery at baseline and at one, two, four, and eight weeks after the operation. The measured data of normal distribution were indicated by the mean ± standard deviation, the independent sample t-test was used among the groups, and the χ2 test was used to compare the counting. Non-normal distribution of the measurement data was carried out using the Mann-Whitney test. RESULTS: Preoperative functional areas, symptom areas and overall health scores were similar in the two groups. The physical, role, emotional and social functions and overall health status of the uniportal group were significantly higher than those of the three-portal group in postoperative time. The score of symptom field was higher in one week after operation, the score of two, four and eight weeks decreased gradually, but it was still above the preoperative level, and the fatigue and pain of the uniportal group were significantly lower than that of the three-portal group. CONCLUSION: The advantages of uniportal VATS include a shorter hospital stay, more rapid recovery and superior cosmetic results compared to three-portal VATS. Additionally, uniportal VATS is superior to three-portal thoracoscopic surgery in terms of the immediate postoperative short-term QOL.
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Adenocarcinoma del Pulmón/cirugía , Carcinoma de Células Escamosas/cirugía , Neoplasias Pulmonares/cirugía , Escisión del Ganglio Linfático/métodos , Neumonectomía/métodos , Calidad de Vida , Cirugía Torácica Asistida por Video/métodos , Adenocarcinoma del Pulmón/patología , Carcinoma de Células Escamosas/patología , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Pronóstico , Estudios ProspectivosRESUMEN
Hydrotreatment is an effective upgrading technology for removing contaminants and saturating double bonds. Still, few studies have reported the hydro-upgrading of shale oil, with unusually high sulfur (13200 ppm) content, using the CoMo/Al2O3 catalyst. Here we report an extensive study on the upgrading of shale oil by hydrotreatment in a stirred batch autoclave reactor (500 ml) for sulfur removal and viscosity reduction. From a preliminary optimization of the reaction factors, the best-operating conditions were 400 °C, an initial H2-pressure of 5 MPa, and an agitation rate of 800 rpm, a catalyst-to-oil ratio of 0.1, and a reaction time of 1 h. We could achieve a sulfur removal efficiency of 87.1% and 88.2% viscosity reduction under the optimal conditions. After that, the spent CoMo/Al2O3 was repeatedly used for subsequent upgrading tests without any form of pre-treatment. The results showed an increase in the sulfur removal efficiency with an increase in the number of catalyst runs. Ultimately, 99.5-99.9% sulfur removal from the shale oil was achieved by recycling the spent material. Both the fresh and the spent CoMo/Al2O3 were characterized and analyzed to ascertain their transformation levels by XRD, TEM, TG, XPS, TPD and N2 adsorption analysis. The increasing HDS efficiency is attributed to the continuing rise in the sulfidation degree of the catalyst in the sulfur-rich shale oil. The light fraction component in the liquid products (IBP-180 °C) was 30-37 vol% higher than in the fresh shale oil. The product oil can meet the sulfur content requirement of the national standard marine fuel (GB17411-2015/XG1-2018) of China.