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Electro-ionic soft actuators have garnered significant attention owing to their promising applications in flexible electronics, wearable devices, and soft robotics. However, achieving high actuation performance (large bending strain and fast response time) of these soft actuators under low voltage has been challenging due to issues related to ion diffusion and accumulation. In this study, an electro-ionic soft actuator is fabricated using Ti3C2Tx MXene and eutectic gallium-indium (EGaIn) composite material as the bilayer electrode and methylammonium formate/1-ethyl-3-methylimidazolium tetrafluoroborate/poly(vinylidene fluoride) (MAF-EMIMBF4/PVDF) as the ionic liquid-type electrolyte. The research results indicate that the prepared soft actuator exhibits excellent actuation performance with a peak-to-peak displacement of 35 mm and a bending strain of 0.69% (a peak-to-peak strain of 1.38%) under a low voltage (3 V). The electro-ionic soft actuator shows a wide frequency range (0.1-10 Hz), fast response time (0.35 s), and a rise time of 7.5 s. Furthermore, it demonstrates good cyclic durability, with a retention rate of 92.5% of its performance for 10 000 cycles. These excellent performances are attributed to the 3D structure of the Ti3C2Tx-EGaIn/Ti3C2Tx bilayer composite electrode, as well as the characteristics of the low viscosity, high conductivity, small ion volume, and larger volume difference between cations and anions in MAF ionic liquid. The high-performance electro-ionic soft actuator can be used in various fields such as artificial muscles, tactile devices, and soft robots.
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Coupling in situ generated intermediates with other substrates/intermediates is a viable approach for diversifying product outcomes of catalytic reactions involving two or multiple reactants. Cyclohexanone oxime is a key precursor for caprolactam synthesis (the monomer of Nylon-6), yet its current production uses unsustainable carbon sources, noble metal catalysts, and harsh conditions. Herein, we report the first work to synthesize cyclohexanone oxime through electroreduction of phenol and hydroxylamine. The Faradaic efficiency reached 69.1% over Cu catalyst, accompanied by a corresponding cyclohexanone oxime formation rate of 82.0 g h-1 gcat-1. In addition, the conversion of phenol was up to 97.5%. In situ characterizations, control experiments, and theoretical calculations suggested the importance of balanced activation of water, phenol, and hydroxylamine substrates on the optimal metallic Cu catalyst for achieving high-performance cyclohexanone oxime synthesis. Besides, a tandem catalytic route for the upgrading of lignin to caprolactam has been successfully developed through the integration of thermal catalysis, electrocatalysis, and Beckmann rearrangement, which achieved the synthesis of 0.40 g of caprolactam from 4.0 g of lignin raw material.
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Dopants can endow lead-free perovskite nanocrystals with novel photoelectric properties. However, understanding the effect of dopants on the structure and energy transfer of lead-free perovskite nanocrystals remains limited. In this work, we synthesize zero-dimensional Cs2ZrCl6 nanocrystals with a blue light quantum yield of up to 75.6% by an improved hot-injection method. And we introduce trace amounts of lanthanide ions (Ln3+) (<â¼8%) in the lattice of nanocrystals and establish an effective energy transfer channel from self-trapped excitons (STEs) to various Ln3+ ions (Tb3+, Eu3+, Dy3+, Sm3+, and Pr3+), which can achieve tunable photoluminescence between red, green and blue. Interestingly, with increasing Ln3+ concentrations (>â¼10%), the phase transition from the cubic phase Cs2ZrCl6:Ln3+ to the monoclinic phase Cs3LnCl6:Zr4+ occurred, while Zr4+ ions began to act as dopants. And a new energy transfer channel from dopant [ZrCl6]2- to host Ln3+ ions was established in the Cs3LnCl6 host accompanied by enhanced broadband photoluminescence excitation (PLE) and photoluminescence (PL). In particular, the photoluminescence quantum yield (PLQY) of Tb3+ ions increases from 0.77% to 54% upon the phase transition (under 276 nm excitation). Our study provides new insights into the effects of dopants on the structure of perovskite nanocrystals and is beneficial to the design of a variety of light-emitting materials for optoelectronic applications.
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Background: The clinical features and prognosis of intussusception in children vaccinated against rotavirus were undefined. Hence, we conducted the study to explore the clinical characteristics and outcomes of primary intussusception patients who received rotavirus vaccine. Methods: A single-center retrospective study was performed in 327 primary intussusception patients between January 2019 and December 2021. Of these, 168 were vaccinated against rotavirus and 159 were not, the latter serving as the control group. Data on patients' clinical characteristics, commonly used inflammatory biomarkers, treatment, and outcomes were collected and evaluated. Results: Most of the vaccination group received pentavalent rotavirus vaccine produced by Merck, USA (89.88%). There were no differences in demographic characteristics, time from onset to hospital attendance, clinical symptoms and signs between the vaccination group and the control group. The success rate of air enema reduction in the vaccination group was higher than that in the control group (98.21% vs. 88.68%, q=0.01). The vaccination group had lower rates of surgery and complication (1.79% vs. 11.32%, q=0.008; 2.98% vs. 12.58%, q=0.006). Both platelet-lymphocyte ratio (PLR) and C-reactive protein (CRP) levels were lower in the vaccinated group (q=0.02, q=0.004). Higher CRP level [odds ratio (OR): 1.635; 95% confidence interval (CI): 1.248-2.143; P=0.006] and the longer time from onset to hospital attendance (OR: 3.040; 95% CI: 2.418-12.133; P=0.01) were associated with increased adverse events. Rotavirus vaccination (OR: 0.527; 95% CI: 0.103-0.751; P=0.02) was associated with a reduction in the probability of adverse events. Conclusions: Adverse events such as surgery and complications were lower in the vaccination group. Rotavirus vaccination was an independent protective factor for adverse events in patients with primary intussusception.
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The access to bench-stable organometallic compounds unfolds new chemical space for medicinal and material sciences. In particular, stable organoruthenium compounds with constitutional and stereoisomeric forms for subtle regulation of electrochemiluminescence are intriguing and challenging. Here, coordination of polycyclic aromatic hydrocarbons on (2-phenylpyridine)2(CO)2Ru complex allows access to bis-polyaryl phenylpyridine (BPP) Ruthenium complex through CâH activation strategy and coupling reactions for installation of the functionalities with steric and electronic purposes. The photoluminescence and electrochemiluminescence of BPP Ru complexes are affected by the actual polycyclic aromatic hydrocarbons inherent properties. The anthracene derivatized BPP Ru complex (BPP-Ant) shows the best ECL performance and reveals an enormous ECL quantum efficiency of 1.6-fold higher than the golden standard Ru(bpy)3 2+. The unprecedentedly high efficiency is due to the best compromise between the structural conjugation and molecular rigidity from BPP-Ant providing a providential energy gap that facilitated the feasibility of electron transfer and favored the radiative energy release by experimentally and DFT calculations. Moreover, PL and spooling ECL spectroscopies are used to track and link multiple emission peaks of BPP-Ant at 445, 645, and 845 nm to different emissive species. These discoveries will add a new member to the efficient ECL ruthenium complex family and bring more potentials.
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The unresolved phylogenetic framework within the Selaginellaceae subfamily Gymnogynoideae (ca. 130 species) has hindered our comprehension of the diversification and evolution of Selaginellaceae, one of the most important lineages in land plant evolution. Here, based on plastid and nuclear data extracted from genomic sequencing of more than 90% species of all genera except two in Gymnogynoideae, a phylogenomic study focusing on the contentious relationships among the genera in Gymnogynoideae was conducted. Our major results included the following: (1) Only single-copy region (named NR) and only one ribosomal operon was firstly found in Afroselaginella among vascular plants, the plastome structure of Gymnogynoideae is diverse among the six genera, and the direct repeats (DR) type is inferred as the ancestral state in the subfamily; (2) The first strong evidence was found to support Afroselaginella as a sister to Megaloselaginella. Alternative placements of Ericetorum and Gymnogynum were detected, and their relationships were investigated by analyzing the variation of phylogenetic signals; and (3) The most likely genus-level relationships in Gymnogynoideae might be: ((Bryodesma, Lepidoselaginella), (((Megaloselaginella, Afroselaginella), Ericetorum), Gymnogynum)), which was supported by maximum likelihood phylogeny based on plastid datasets, maximum likelihood, and Bayesian inference based on SCG dataset and concatenated nuclear and plastid datasets and the highest proportion of phylogenetic signals of plastid genes.
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Achieving satisfactory multi-carbon (C2+) products selectivity and current density under acidic condition is a key issue for practical application of electrochemical CO2 reduction reaction (CO2RR), but is challenging. Herein, we demonstrate that combining microenvironment modulation by porous channel structure and intrinsic catalytic activity enhancement via doping effect could promote efficient CO2RR toward C2+ products in acidic electrolyte (pH ≤ 1). The La-doped Cu hollow sphere with channels exhibits a C2+ products Faradaic efficiency (FE) of 86.2% with a partial current density of -775.8 mA cm-2. CO2 single-pass conversion efficiency for C2+ products can reach 52.8% at -900 mA cm-2. Moreover, the catalyst still maintains a high C2+ FE of 81.3% at -1 A cm-2. The channel structure plays a crucial role in accumulating K+ and OH- species near the catalyst surface and within the channels, which effectively suppresses the undesired hydrogen evolution and promotes C-C coupling. Additionally, the La doping enhances the generation of *CO intermediate, and also facilitates C2+ products formation.
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Conductive hydrogels with high performance and frost resistance are essential for flexible electronics, electronic skin, and soft robots. Nonetheless, the preparation of hydrogel-based flexible strain sensors with rapid response, wide strain detection range, and high sensitivity remains a considerable challenge. Furthermore, the inevitable freezing and evaporation of water in sub-zero temperatures and dry environments lead to the loss of flexibility and conductivity in hydrogels, which seriously limits their practical application. In this work, ionic liquids (ILs) and MXene are introduced into gelatin/polyacrylamide (PAM) precursor solution, and a PAM/gelatin/ILs/MXene/glycerol (PGIMG) hydrogel-based flexible strain sensor with MXene co-ILs ion-electron composite conductive network is prepared by combining the electrohydrodynamic (EHD) printing method and in-situ photopolymerization. The introduction of ILs provides an ionic conductive channel for the hydrogel. The introduction of MXene nanosheets forms an interpenetrating network with gelatin and PAM, which not only provides a conductive channel, but also improves the mechanical and sensing properties of the hydrogel-based flexible strain sensor. The prepared PGIMG hydrogel with the MXene co-ILs ion-electron composite conductive network demonstrates a tensile strength of 0.21 MPa at 602.82 % strain, the conductivity of 1.636 × 10-3 S/cm, high sensitivity (Gauge Factor, GF = 4.17), a wide strain detection range (1-600 %), and the response/recovery times (73 ms and 74 ms). In addition, glycerol endows the hydrogel with excellent freezing (-60 °C) and water retention properties. The application of the hydrogel-based flexible strain sensor in the field of human motion detection and information transmission shows the great potential of wearable devices, electronic skin, and information encryption transmission.
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Hydrogels have emerged as promising candidates for biomedical applications, especially in the field of antibacterial therapeutics, due to their unique structural properties, highly tunable physicochemical properties, and excellent biocompatibility. The integration of stimuli-responsive functions into antibacterial hydrogels holds the potential to enhance their antibacterial properties and therapeutic efficacy, dynamically responding to different external or internal stimuli, such as pH, temperature, enzymes, and light. Therefore, this review describes the applications of hydrogel dressings responsive to different stimuli in antibacterial therapy. The collaborative interaction between stimuli-responsive hydrogels and antibacterial materials is discussed. This synergistic approach, in contrast to conventional antibacterial materials, not only amplifies the antibacterial effect but also alleviates adverse side effects and diminishes the incidence of multiple infections and drug resistance. The review provides a comprehensive overview of the current challenges and outlines future research directions for stimuli-responsive antibacterial hydrogels. It underscores the imperative for ongoing interdisciplinary research aimed at unraveling the mechanisms of wound healing. This understanding is crucial for optimizing the design and implementation of stimuli-responsive antibacterial hydrogels. Ultimately, this review aims to offer scientific guidance for the development and practical clinical application of stimuli-responsive antibacterial hydrogel dressings.
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Hydroxylamine (HA, NH2OH) is a critical feedstock in the production of various chemicals and materials, and its efficient and sustainable synthesis is of great importance. Electroreduction of nitrate on Cu-based catalysts has emerged as a promising approach for green ammonia (NH3) production, but the electrosynthesis of HA remains challenging due to overreduction of HA to NH3. Herein, we report the first work on ketone-mediated HA synthesis using nitrate in water. A metal-organic-framework-derived Cu catalyst was developed to catalyze the reaction. Cyclopentanone (CP) was used to capture HA in situ to form CP oxime (CP-O) with CâN bonds, which is prone to hydrolysis. HA could be released easily after electrolysis, and CP was regenerated. It was demonstrated that CP-O could be formed with an excellent Faradaic efficiency of 47.8%, a corresponding formation rate of 34.9 mg h-1 cm-2, and a remarkable carbon selectivity of >99.9%. The hydrolysis of CP-O to release HA and CP regeneration was also optimized, resulting in 96.1 mmol L-1 of HA stabilized in the solution, which was significantly higher than direct nitrate reduction. Detailed in situ characterizations, control experiments, and theoretical calculations revealed the catalyst surface reconstruction and reaction mechanism, which showed that the coexistence of Cu0 and Cu+ facilitated the protonation and reduction of *NO2 and *NH2OH desorption, leading to the enhancement for HA production.
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Recently, metal-halide perovskites have rapidly emerged as efficient light emitters with near-unity quantum yield and size-dependent optical and electronic properties, which have attracted considerable attention from researchers. However, the ultrafast nucleation rate of ionic perovskite counterparts severely limits the in-depth exploration of the growth mechanism of colloidal nanocrystals (NCs). Herein, we used an inorganic ligand nitrosonium tetrafluoroborate (NOBF4) to trigger a slow post-synthesis transformation process, converting non-luminescent Cs4PbBr6 NCs into bright green luminescent CsPbBr3 NCs to elucidate the concrete transformation mechanism via four stages: (i) the dissociation of pristine NCs, (ii) the formation of Pb-Br intermediates, (iii) low-dimensional nanoplatelets (NPLs) and (iv) cubic CsPbBr3 NCs, corresponding to the blue-to-green emission process. The desorption and reorganization of organic ligands induced by NO+ and the involvement of BF4- in the ligand exchange process played pivotal roles in this dissolution-recrystallization of NCs. Moreover, controlled shape evolution from anisotropic NPLs to NCs was investigated through variations in the amount of NOBF4. This further validates that additives exert a decisive role in the symmetry and growth of nanostructured perovskite crystals during phase transition based on the ligand-exchange mechanism. This finding serves as a source of inspiration for the synthesis of highly luminescent CsPbBr3 NCs, providing valuable insights into the chemical mechanism in post-synthesis transformation.
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Flexible and room-temperature (RT) ammonia gas sensors are needed for exhaled breath detection and recognition. Two-dimensional transition metal disulfides are potential materials for RT gas sensing because of their low band gap and a large number of edge-exposed sites that can provide strong binding to gas molecules. In this work, a 1D/2D heterostructured composite material of 2D tungsten disulfide (WS2) modified with 1D polyaniline (PANI) was proposed. The fibrous PANI adsorbed on the edges and inserted in the interlayers of the laminated WS2 provide more diffusion channels for the ammonia gas and act as sensing sites. The WS2@PANI-based sensor shows high selectivity for ammonia with satisfying reproducibility and long-term stability. A response of 216.3% and a short response/recovery time of 25 s/39 s were achieved for 100 ppm ammonia gas. The sensing mechanism was investigated in detail via complex impedance spectra and in situ FT-IR, which was attributed to the synergistic effect of WS2 and PANI. The excellent sensing performance coupled with its resistance to thermal and humidity interference endows the WS2@PANI-based sensor with potential for human exhaled detection and wearable electronics.
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An advanced nanoplatform was developed by integrating catalytic hairpin assembly (CHA) with glutathione-responsive nanocarriers, enabling superior imaging of dual cancer-related miRNAs. Two distinct CHA circuits for the sensing of miRNA-21 and miRNA-155 were functionalized on biodegraded MnO2. In the presence of GSH and the corresponding miRNAs, the degraded MnO2 released the DNA cargos, activating the CHA circuits and recovering the fluorescence. This approach offers a reliable sensing performance with highly selective cell-identification capacity, positioning it as a pivotal tool for imaging multiple biomarkers in living cells.
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Técnicas Biossensoriais , DNA Catalítico , MicroRNAs , MicroRNAs/genética , Compostos de Manganês , Técnicas Biossensoriais/métodos , Óxidos , DNARESUMO
Eucommia ulmoides tea is a popular functional health drink in Asian countries, but its unique herbal aroma is difficult for consumers to accept. The effects of four lactic acid bacteria strains (Lactobacillus plantarium, Lactobacillus bulgaricus, Lactobacillus acidophilus and Streptococcus thermophilus) fermentation on the physicochemical property, antioxidant activity in vitro and aroma component of E. ulmoides leaves were studied. Within the four strains, the sample by L. bulgaricus fermentation showed the higher concentrations of chlorogenic acid, geniposidic acid and stronger antioxidant activity in vitro. Moreover, the sample by L. bulgaricus fermentation produced a stronger fruity and floral flavor. These results suggested that L. bulgaricus was the best strain for fermentation E. ulmoides tea. The differences between different strains should be considered when selecting lactic acid bacteria for raw material fermentation of fruits and vegetables.
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BACKGROUND: Gastrointestinal perforation in extremely low birth weight infants, characterized by its rapid onset, multiple complications, and critical condition, poses a significant risk of infant mortality. The aim of this study was to investigate the clinical characteristics of pneumoperitoneum in extremely low birth weight infants (ELBWI) and explore the risk factors associated with gastrointestinal perforation in very low birth weight preterm infants. Additionally, we shared our surgical experiences in managing gastrointestinal perforation among extremely low birth weight infants. METHODS: The Department of Neonatology at Chengdu Women and Children's Central Hospital conducted a retrospective study on gastrointestinal perforation in extremely low birth weight infants (birth weight <1000 g) who were admitted between 2014 and 2021. After baseline analysis and comparing it with the control group, we identified the risk factors associated with gastrointestinal perforation in ELBWI by multiple logistic regression analysis. The Kaplan-Meier analysis was performed to assess the adverse effect of gastrointestinal perforation for survival in ELBW infants. Cox multivariate regression analysis was used to evaluate hazard level of different variables for ELBW infants survival. RESULTS: Hemodynamically significant patent ductus arteriosus (hsPDA)(p = 0.043, OR = 2.779) and sepsis (p = 0.014, OR = 2.265) were significant risk factors for gastrointestinal perforation in extremely low birth weight infants. The Cox proportional hazard model revealed that intraventricular hemorrhage (HR = 2.854, pï¼0.001) Sepsis (HR = 1.645, p = 0.015) and gastrointestinal perforation (HR = 1.876, p = 0.008) had detrimental effects on the survival of extremely low birth weight infants; conversely, ibuprofen (HR = 0.304, pï¼0.001) and blood transfusion (HR = 0.372, pï¼0.001) are beneficial factors for their survival. The preoperative indicators of infection in infants with spontaneous intestinal perforation (SIP) were significantly better than those in the necrotizing enterocolitis (NEC) group (p < 0.05). CONCLUSIONS: Gastrointestinal perforation poses a significant threat the survival of extremely low birth weight (ELBW) infants, with hsPDA and sepsis serving as predisposing factors for gastrointestinal perforation. The gastrointestinal perforation caused by various diseases exhibits distinct clinical characteristics, necessitating tailored surgical approaches based on operative conditions.
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Permeabilidade do Canal Arterial , Perfuração Intestinal , Sepse , Lactente , Criança , Recém-Nascido , Humanos , Feminino , Recém-Nascido de Peso Extremamente Baixo ao Nascer , Recém-Nascido Prematuro , Estudos Retrospectivos , Peso ao Nascer , Permeabilidade do Canal Arterial/cirurgia , Perfuração Intestinal/epidemiologia , Perfuração Intestinal/etiologia , Perfuração Intestinal/cirurgiaRESUMO
Direct fixation of N2 to N-containing value-added chemicals is a promising pathway for sustainable chemical manufacturing. There is extensive demand for cyclohexanone oxime because it is the essential feedstock of Nylon 6. Currently, cyclohexanone oxime is synthesized under harsh conditions that consume a considerable amount of energy. Herein, we report a novel approach to synthesize cyclohexanone oxime by in situ NO3- generation from air under ambient conditions. This process was carried out through an integrated strategy including plasma-assisted air-to-NOx and co-electrolysis of NOx and cyclohexanone. A high rate of cyclohexanone oxime formation at 20.1 mg h-1 cm-2 and a corresponding faradaic efficiency (FE) of 51.4% was achieved over a Cu/TiO2 catalyst, and the selectivity of cyclohexanone oxime was >99.9% on the basis of cyclohexanone. The C-N bond formation mechanism was examined by in situ experiments and theoretical calculations, which showed that cyclohexanone oxime forms through the reaction between an NH2OH intermediate and cyclohexanone.
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Metal-organic frameworks (MOFs) have broad potential applications in electrochemical glucose detection. Herein, a green ultrasonic synthesis process is presented for preparing two-dimensional (2D) copper-nickel metal-organic framework nanosheets (CuNi-MOFNs) for glucose detection. The synthesized CuNi-MOFNs were characterized using scanning electron microscopy (SEM), scanning transmission electron microscope (STEM), X-ray diffractometer (XRD), and X-ray photoelectron spectrometer (XPS). The CuNi-MOFN nanocomposites were used to cover the glassy carbon electrode (GCE) and the CuNi-MOFNs-modified electrode was studied in alkaline media. Cyclic voltammetry (CV) and amperometric i-t curves indicated that the CuNi-MOFNs-modified electrode revealed great electrochemical performances towards glucose oxidation. Due to the ease of access to active metal sites in large specific surface of nanosheets, the CuNi-MOFNs-modified electrode can effectively improve the electronic transfer rate and enhance electrocatalytic activity of the CuNi-MOFNs-modified electrode. The CuNi-MOFNs-modified electrode showed electrochemical performances for glucose detection with a linear range from 0.01 mM to 4 mM, sensitivity of 702 µAmM-1cm-2, and detection limit of 3.33 µΜ (S/N = 3). The CuNi-MOFNs-modified electrode exhibited excellent anti-interference ability and high selectivity in glucose measurements. Hence, the CuNi-MOFNs-modified electrode has good, promising prospects in non-enzymatic electrochemical glucose detection.
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In recent years, there has been a growing demand for luminescence anticounterfeiting materials that possess the properties of environmentally friendly, single-component, and multimode fluorescence. Among the materials explored, the low dimensional metal halides have gained wide attention because of unique characteristics including low toxicity, simple synthesis, good stability, and so on. Here, we synthesized Mn2+ and Sb3+ codoped Cs2ZnCl4 single crystals by a facile hydrothermal method. Under 365 nm excitation, the codoped compound exhibits dual-band emissions at 530 and 730 nm. However, under 316 nm excitation, the compound only shows one emission band from 500 to 850 nm peaking at 730 nm, while under 460 nm excitation, the emission from 500 to 650 nm with an emission peak at 530 nm can be observed. Based on the study of the photoluminescence mechanism, the green and red emissions originate from the Mn2+ located in the tetrahedron and self-trapped exciton emission of [SbCl4]- clusters, respectively. Due to the zero-dimensional structure of the Cs2ZnCl4 host, there is minimal energy transfer between these dopants. Consequently, the luminous ratios of the two emissions can be independently regulated. Except by tuning the dopant concentrations, the Cs2ZnCl4:Mn2+, Sb3+ demonstrates excitation-wavelength-dependent properties, which could emit more than two colors with the change of excitation wavelength. As a result, multimode anticounterfeiting based on Cs2ZnCl4:Mn2+, Sb3+ crystals has been designed, which aligns with the requirements of environmentally friendly, single-component, and multimode fluorescence properties.