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1.
Nature ; 631(8022): 783-788, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38961297

RESUMO

Three-dimensional (3D) printing has emerged as an attractive manufacturing technique because of its exceptional freedom in accessing geometrically complex customizable products. Its potential for mass manufacturing, however, is hampered by its low manufacturing efficiency (print speed) and insufficient product quality (mechanical properties). Recent progresses in ultra-fast 3D printing of photo-polymers1-5 have alleviated the issue of manufacturing efficiency, but the mechanical performance of typical printed polymers still falls far behind what is achievable with conventional processing techniques. This is because of the printing requirements that restrict the molecular design towards achieving high mechanical performance. Here we report a 3D photo-printable resin chemistry that yields an elastomer with tensile strength of 94.6 MPa and toughness of 310.4 MJ m-3, both of which far exceed that of any 3D printed elastomer6-10. Mechanistically, this is achieved by the dynamic covalent bonds in the printed polymer that allow network topological reconfiguration. This facilitates the formation of hierarchical hydrogen bonds (in particular, amide hydrogen bonds), micro-phase separation and interpenetration architecture, which contribute synergistically to superior mechanical performance. Our work suggests a brighter future for mass manufacturing using 3D printing.

2.
Macromol Rapid Commun ; 45(5): e2300586, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37972640

RESUMO

Integrating diverse materials and functions into highly additive produce has piqued global interest due to the increasing demands of intelligent soft robotics. Nevertheless, existing assembly techniques, especially supramolecular assembly which heavily rely on precise chemical design and specific recognition, may prove inadequate when confronted with diverse external demands. Inspired by the traditional mechanical assembly, rivet connection, herein, a thermo-responsive hydrogel with unidirectional shape-morphing is fabricated and a stable mechanical assembly is constructed by emulating the rivet connection mechanism. This system employed poly(acrylamide-co-acrylic acid) [P(AAm-co-AAc)] to induce continuous swelling and hexylamine-modified polyvinyl alcohol (PVA-C6) as a molecular switch to control the swelling process. The hydrogel rivet, initially threaded through pre-fabricated hollows in two components. Subsequently, upon the disassociation of alkane chains the molecular switch would activate, inducing swelling and stable mechanical assembly via anchor structures. Moreover, to enhance the assembly strength, knots are introduced to enhance assembly strength, guiding localized stress release for programmed deformations. Additionally, the system can be remotely controlled using near-infrared light (NIR) by incorporating photo-thermal nanoparticles. This work presents a universal and efficient strategy for constructing stable mechanical assemblies without compromising overall softness, offering significant potential for the fabrication of integrated soft robots.


Assuntos
Hidrogéis , Nanopartículas , Hidrogéis/química , Álcool de Polivinil/química , Raios Infravermelhos
3.
Angew Chem Int Ed Engl ; : e202413788, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39313750

RESUMO

Strong metal-support interactions (SMSI) are crucial for stabilizing sub-2 nm metal sites, e.g. single atom (M1) or cluster (Mn). However, further optimizing sub-2 nm sites to break the activity-stability trade-off due to excessive interactions remains significant challenges. Accordingly, for the first time, we propose synergizing SMSI with reactive metal-support interactions (RMSI). Comprehensive characterization confirms that the SMSI stabilizes the metal and regulates the aggregation of Ni1 into Nin site within sub-2 nm. Meanwhile, RMSI modulates Nin through sufficiently activating P in the support and eventually generates sub-2 nm metal phosphide Ni2P cluster (Ni2Pn). The synergetic metal-support interactions triggered the adaptive coordination and electronic structure optimization of Ni2Pn, leading to the desired substrate adsorption-desorption kinetics. Consequently, the activity of Ni2Pn site greatly enhanced towards the selective hydrogenations of p-chloronitrobenzene and alkynyl alcohol. The formation rates of target products are up to 20.2 and 3.0 times greater than that of Ni1 and Nin site, respectively. This work may open a new direction for metal-support interactions and promote innovation and application of active sites below 2 nm.

4.
Glob Chang Biol ; 29(16): 4670-4685, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37221551

RESUMO

Continued current emissions of carbon dioxide (CO2 ) and methane (CH4 ) by human activities will increase global atmospheric CO2 and CH4 concentrations and surface temperature significantly. Fields of paddy rice, the most important form of anthropogenic wetlands, account for about 9% of anthropogenic sources of CH4 . Elevated atmospheric CO2 may enhance CH4 production in rice paddies, potentially reinforcing the increase in atmospheric CH4 . However, what is not known is whether and how elevated CO2 influences CH4 consumption under anoxic soil conditions in rice paddies, as the net emission of CH4 is a balance of methanogenesis and methanotrophy. In this study, we used a long-term free-air CO2 enrichment experiment to examine the impact of elevated CO2 on the transformation of CH4 in a paddy rice agroecosystem. We demonstrate that elevated CO2 substantially increased anaerobic oxidation of methane (AOM) coupled to manganese and/or iron oxides reduction in the calcareous paddy soil. We further show that elevated CO2 may stimulate the growth and metabolism of Candidatus Methanoperedens nitroreducens, which is actively involved in catalyzing AOM when coupled to metal reduction, mainly through enhancing the availability of soil CH4 . These findings suggest that a thorough evaluation of climate-carbon cycle feedbacks may need to consider the coupling of methane and metal cycles in natural and agricultural wetlands under future climate change scenarios.


Assuntos
Oryza , Solo , Humanos , Dióxido de Carbono/análise , Anaerobiose , Metano/metabolismo , Agricultura , Oryza/metabolismo
5.
J Environ Sci (China) ; 127: 866-874, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36522114

RESUMO

Liquid-liquid extraction (LLE) using ionic liquids (ILs)-based methods to remove perfluoroalkyl chemicals (PFACs), such as perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), from wastewater, is an important strategy. However, the lack of physicochemical and LLE data limits the selection of the most suitable ILs for the extraction of PFACs. In this work, 1763 ILs for PFACs extraction from water were systematically screened using COSMOtherm to estimate the infinite dilution activity coefficient (lnγ∞)of PFOA and PFOS in water and ILs. To evaluate the accuracy of COSMOtherm, 8 ILs with various lnγ∞ values were selected, and their extraction efficiency (E) and distribution coefficient (Dexp) were measured experimentally. The results showed that the predicted lnγ∞ decreased as the increase of experimental extraction efficiency of PFOA or PFOS, while the tendency of predicted distribution coefficient (Dpre) was consistent with the experimental (Dexp) results. This work provides an efficient basis for selecting ILs for the extraction of PFACs from wastewater.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Líquidos Iônicos , Águas Residuárias , Caprilatos , Água
6.
Acc Chem Res ; 51(1): 80-88, 2018 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-29227617

RESUMO

Stable electrochemical interphases play a critical role in regulating transport of mass and charge in all electrochemical energy storage (EES) systems. In state-of-the-art rechargeable lithium ion batteries, they are rarely formed by design but instead spontaneously emerge from electrochemical degradation of electrolyte and electrode components. High-energy secondary batteries that utilize reactive metal anodes (e.g., Li, Na, Si, Sn, Al) to store large amounts of charge by alloying and/or electrodeposition reactions introduce fundamental challenges that require rational design in order to stabilize the interphases. Chemical instability of the electrodes in contact with electrolytes, morphological instability of the metal-electrolyte interface upon plating and stripping, and hydrodynamic-instability-induced electroconvection of the electrolyte at high currents are all known to cause metal electrode-electrolyte interfaces to continuously evolve in morphology, uniformity, and composition. Additionally, metal anodes undergo large changes in volume during lithiation and delithiation, which means that even in the rare cases where spontaneously formed solid electrode-electrolyte interphases (SEIs) are in thermodynamic equilibrium with the electrode, the SEI is under dynamic strain, which inevitably leads to cracking and/or rupture during extended battery cycling. There is an urgent need for interphases that are able to overcome each of these sources of instability with minimal losses of electrolyte and electrode components. Complementary chemical synthesis strategies are likewise urgently needed to create self-limited and mechanically durable SEIs that are able to flex and shrink to accommodate volume change. These needs are acute for practically relevant cells that cannot utilize large excesses of anode and electrolyte as employed in proof-of-concept-type experiments reported in the scientific literature. This disconnect between practical needs and research practices makes it difficult to translate promising literature results, underscoring the importance of research designed to reveal principles for good interphase design. This Account considers the fundamental processes involved in interphase formation, stability, and failure and on that basis identifies design principles, synthesis procedures, and characterization methods for enabling stable metal anode-electrolyte interfaces for EES. We first review results from experimental, continuum theoretical, and computational analyses of interfacial transport to identify fundamental connections between the composition of the SEI at metal-electrolyte interfaces and stability. Design principles and tools for creating stable artificial solid-electrolyte interphases (ASEIs) based on polymers, ionic liquids, ceramics, nanoparticles, salts, and their combinations are subsequently discussed. Interphases composed of a second electrochemically active material that stores charge by different processes from the underlying metal electrode emerge as particularly attractive routes toward so-called hybrid electrodes that enable facile scale-up of ASEI designs for commercially relevant EES.

7.
Environ Sci Technol ; 53(12): 6937-6944, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-31117533

RESUMO

Increasing numbers of cement furnaces have applied selective catalytic reduction (SCR) units for advanced treatment of NO in the flue gas. However, the SCR catalysts may face various poisons, such as acidic, alkaline, and heavy metal species, in the fly ash. In this work, we studied the deactivation mechanisms of multipoisons (Ca, Pb, and S) on the CeO2-WO3/TiO2 catalyst, using the in situ diffuse reflectance infrared Fourier transform spectroscopy method. Calcium promoted the conversion of Ce(III) to Ce(IV) and, thus, (i) suppressed the redox cycle, (ii) decreased the NO adsorption (monodentate NO3- and bridged NO2-), and (iii) enriched the Lewis acid sites. Pb(IV) blocked Ce2(WO4)3, aggravating the electronegativity of W6+, which inhibited (i) the binding stability of tungsten and ammonia species, (ii) bridged NO3- (bonded to tungsten), and (iii) the Brønsted acid sites. The multipoisoning processes enriched O2- by repairing partial surface oxygen defects, which suppressed O22- and O-. Sulfur occupied the surface base sites and formed PbSO4 after Ce2(WO4)3 was saturated.


Assuntos
Cério , Amônia , Catálise , Oxirredução , Tungstênio
8.
Environ Sci Technol ; 53(23): 13784-13793, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31687808

RESUMO

Reducing energy use is crucial to commercialize electrochemical oxidation technologies. We developed a three-dimensional (3-D) electrochemical system that can significantly reduce the applied voltage and effectively degrade organic contaminants in low-ionic-strength wastewaters. The 3-D system consisted of a composite wire mesh anode (composed of blue TiO2 nanotubes covered with SnO2-Sb2O3), a proton exchange membrane, and a stainless-steel wire mesh cathode, which were compressed firmly together. For the 3-D system, we placed the anode of a 3-D electrode toward the wastewater that flowed past the anode. Both the two-dimensional (2-D) and 3-D systems had the same anode and cathode. We found that the 3-D system could reduce the applied voltage by 75.7% and reduce the electrical efficiency per log order reduction (EE/O) by 73% for 0.001 M Na2SO4. For Na2SO4 concentrations greater than 0.05 M, the 2-D system had a slightly lower EE/O. We also compared the EE/O of electrochemical advanced oxidation processes (EAOPs) with that of other advanced oxidation processes (UV/H2O2, UV/persulfate, O3/H2O2, UV/ TiO2, and UV/chlorine). We found that EAOPs have a much higher EE/O for low BA concentrations (20 mg/L) and a much lower EE/O for high BA concentrations (2000 mg/L).


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Técnicas Eletroquímicas , Eletrodos , Peróxido de Hidrogênio , Concentração Osmolar , Oxirredução
9.
Environ Monit Assess ; 191(12): 709, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31677005

RESUMO

With the increase of population, many cities are growing in size at a phenomenal rate. Urbanization changes the urban underlying surface, influences the micro-climate, and sometimes affects the local precipitation process. In this study, we investigated the trends of extreme rainfall in China's 21 typical urban areas. Based on a series of daily rainfall and "Urban/built-up" dataset from TMPA 3B42 and MCD12Q1 products in China, trends in extreme precipitation, with the threshold defined as 95th (pre95p) and 99th (pre99p) percentiles of annual rain days during 1998-2015, have been assessed in China, and especially in 21 typical urban areas from 1998 to 2015. The tendency curves in extreme rainfall of different years are presented. In this period, more than 66% regions of China covered by TMPA 3B42 have increasing trends in extreme rainfall with pre95p threshold. The 21 typical urban areas showed different trends-in over half of these areas, upward tendencies in extreme rainfall were observed, particularly in Dalian, Beijing, and Chongqing. Seventeen urban areas showed increasing tendencies in pre95p extreme rainfall days, including Shanghai, Nanjing, Hangzhou, and Suzhou in the Yangtze River Delta region. The results also illustrate that southeastern coastal urban areas of China may have experienced decreasing occurrences in extreme rainfall.


Assuntos
Monitoramento Ambiental/métodos , Chuva , Pequim , China , Cidades , Clima , Tecnologia de Sensoriamento Remoto , Rios , Urbanização
10.
Angew Chem Int Ed Engl ; 57(4): 992-996, 2018 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-29227557

RESUMO

We report a facile in situ synthesis that utilizes readily accessible SiCl4 cross-linking chemistry to create durable hybrid solid-electrolyte interphases (SEIs) on metal anodes. Such hybrid SEIs composed of Si-interlinked OOCOR molecules that host LiCl salt exhibit fast charge-transfer kinetics and as much as five-times higher exchange current densities, in comparison to their spontaneously formed analogues. Electrochemical analysis and direct optical visualization of Li and Na deposition in symmetric Li/Li and Na/Na cells show that the hybrid SEI provides excellent morphological control at high current densities (3-5 mA cm-2 ) for Li and even for notoriously unstable Na metal anodes. The fast interfacial transport attributes of the SEI are also found to be beneficial for Li-S cells and stable electrochemical cycling was achieved in galvanostatic studies at rates as high as 2 C. Our work therefore provides a promising approach towards rational design of multifunctional, elastic SEIs that overcome the most serious limitations of spontaneously formed interphases on high-capacity metal anodes.

11.
Langmuir ; 33(42): 11164-11169, 2017 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-28851215

RESUMO

Li4Ti5O12 (LTO) is a promising anode material for electric vehicles (EVs) and electrochemical energy storage applications because of its safety, good rate capability, and long cycle life. At elevated temperature, such as 60 °C, it always shows poor cycle performance because of the instability between the electrode material and electrolyte, which may also lead to a serious gassing issue. In this article, a facile hydrothermal method is adopted to coat the LTO powder with a thin LiF layer, in which the LiF acts as an artificial solid electrolyte interface (SEI) layer to prevent the direct contact of LTO and electrolyte, thus improving the high-temperature cycle performance. Electrochemical tests prove that the LiF coating layer has no influence on the kinetics at ambient temperature and greatly enhances the high-temperature cycle stability, and the LTO@LiF composite material keeps 87% of its initial discharge capacity in 300 1C cycles at 60 °C. Moreover, the LiF coating layer exhibits a special self-driven reforming process during the initial cycles, which makes it uniform and more effective at enhancing the stability between electrode/electrolyte interfaces.

12.
Chemosphere ; 362: 142480, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38849100

RESUMO

The research investigated the pulse potential effect on Electrochemical Advanced Oxidation Processes (EAOPs) for benzoic acid oxidation. The current efficiency of the electrooxidation is enhanced by changing the pulse frequency and potential on electrodes. The experiments showed that there are opposing phenomena affecting energy efficiency. On the one hand, pulse potential accelerates the mass transfer of benzoic acid in an electric field. On the other hand, pulse potential increases the non-faradic current that uses energy without causing oxidation. Using the Sand equation and the electric double-layer theory, we optimized the pulse frequency and voltage amplitude to achieve the highest energy efficiency for the pulse potential EAOPs. Compared with DC (Direct current) EAOPs, the pulse potential EAOPs save 50% EE/O and have a 41 % CE for the 4_2 V cycle at 50 Hz. Therefore, pulse potential EAOPs can achieve both high pollutant degradation efficiency and low energy consumption at the same time.


Assuntos
Ácido Benzoico , Técnicas Eletroquímicas , Oxirredução , Técnicas Eletroquímicas/métodos , Ácido Benzoico/química , Eletrodos
13.
Adv Mater ; 36(16): e2313078, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38231117

RESUMO

Dielectric elastomers (DEs) are actuatable under an electric field, whose large strain and fast response speed compare favorably with natural muscles. However, the actuation of DE-based devices is generally limited to a single mode and cannot be reconfigured after fabrication, which pales in comparison to biological counterparts given the ability to alter actuation modes according to external conditions. To address this, liquid crystal dielectric elastomers (LC-DEs) that can alter the dielectric actuation modes based on the thermally triggered shape-changing are prepared. Specifically, the two shapes through the LC phase transition possess different bending stiffness, which leads to distinct actuation modes after an electric field is applied. Moreover, the two shapes can be individually programmed/reprogrammed, that is, the one before the transition is regulated through force-directed solvent evaporation and the one after the transition is via bond exchange-enabled stress relaxation. As such, the multimodal dielectric actuation behaviors upon temperature change can be readily diversified. Meanwhile, the space charge mechanism endows LC-DEs with the significantly reduced driving e-field (8 V µm-1) and bidirectional actuation manners. It is believed this unique adaptivity in the actuation modes under a low electric field shall offer versatile designs for practical soft robots.

14.
Nanoscale ; 16(41): 19355-19363, 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39324893

RESUMO

Self-powered sensors are pivotal in sectors like space exploration, industrial monitoring, and particularly health surveillance, owing to their independence from external power sources. However, their energy utilization efficiency is hindered by complex energy conversion processes, leading to brief operational durations and significant data loss. Triboelectric nanogenerators (TENGs), capable of converting mechanical energy from friction into electricity, present a solution by enabling single-cycle sensing and transmission, thus promoting instantaneous wireless sensing. Addressing the size and transmission limitations in wearable technologies, we introduced an instantaneous self-powered wireless sensing system based on a TENG and a human body (HB-WTENG). This novel system utilizes the human body as a transmission antenna, converting TENG output into attenuated sinusoidal signals with encoded sensing information for real-time wireless communication. Demonstrated to support self-powered pressure sensing and signal transmission up to 8 m, the HB-WTENG offers a compact and deployable solution for continuous monitoring, marking a significant advancement in wearable sensor technology.


Assuntos
Fontes de Energia Elétrica , Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio , Humanos , Tecnologia sem Fio/instrumentação , Nanotecnologia/instrumentação , Desenho de Equipamento , Corpo Humano
15.
Adv Mater ; 36(35): e2405733, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39003615

RESUMO

Precise control over the size, species, and breakthrough of the activity-selectivity trade-off are great challenges for sub-nano non-noble metal catalysts. Here, for the first time, a "multiheteroatom induced SMSI + in situ P activation" strategy that enables high stability and effective construction of sub-2 nm metal sites for optimizing selective hydrogenation performance is developed. It is synthesized the smallest metal phosphide clusters (<2 nm) including from unary to ternary non-noble metal systems, accompanied by unprecedented thermal stability. In the proof-of-concept demonstration, further modulation of size and species results in the creation of a sub-2 nm site platform, directionally achieving single atom (Ni1), Ni1+metal cluster (Ni1+Nin), or novel Ni1+metal phosphide cluster synergistic sites (Ni1+Ni2Pn), respectively. Based on thorough structure and mechanism investigation, it is found the Ni1+Ni2Pn site is motivated to achieve electronic structure self-optimizing through synergistic SMSI and site coupling effect. Therefore, it speeds up the substrate adsorption-desorption kinetics in semihydrogenation of alkyne and achieves superior catalytic activity that is 56 times higher than the Ni1 site under mild conditions. Compared to traditional active sites, this may represent the highly effective integration of atom utilization, thermal stability, and favorable site requirements for chemisorption properties and reactivities of substrates.

16.
ACS Macro Lett ; 13(8): 1037-1042, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39078044

RESUMO

Catalyst-free, volatile organic solvent (VOC)-free synthesis of biobased cross-linked polymers is an important sustainable feature in polyesterification. To date, these polyesters have been extensively studied for their fundamental sustainability across various uses. The ultimate potential sustainability for these materials, however, is constrained to static structural parts due to their intractable rigid three-dimensional (3D) network. Here, we reveal intrinsic dynamic exchangeable bonds within this type of cross-linked semicrystalline network, poly(1,8-octanediol-co-1,12-docanedioate-co-citrate) (PODDC), enabling permanent shape reconfigurability. Annealing at slightly above melting-transition temperature (Tm) allows for shape reconfigurability up to nine times, comparable in performance to the existing bond-exchange systems. No reagents are involved from synthesis to shape reconfiguration, suggesting an exciting feature exhibited by this sustainable cross-linked material without the need for further chemical modification. We further extend this benefit of reconfigurability to enable flexible shape design in a smart shape-memory polymer (SMP), showing it as one of its potential applications. After its applications, it can undergo hydrolytic degradation. We envision that such multifaceted sustainability for the material will attract interest in environmentally friendly applications such as fabricating external part of soft robots and shape-morphing devices with reduced environmental impact.

17.
Soft Robot ; 10(6): 1099-1114, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37437102

RESUMO

With intrinsic compliance, soft pneumatic actuators are widely utilized in delicate tasks. However, complex fabrication approaches and limited tunability are still problems. Here, we propose a tunable folding assembly strategy to design and fabricate soft pneumatic actuators called FASPAs (folding assembly soft pneumatic actuators). A FASPA consists only of a folded silicone tube constrained by rubber bands. By designing local stiffness and folding manner, the FASPA can be designed to achieve four configurations, pure bending, discontinuous-curvature bending, helix, and discontinuous-curvature helix. Analytical models are developed to predict the deformation and the tip trajectory of different configurations. Meanwhile, experiments are performed to verify the models. The stiffness, load capacity, output force, and step response are measured, and fatigue tests are performed. Further, grippers with single, double, and triple fingers are assembled by utilizing different types of FASPAs. As such, objects with different shapes, sizes, and weights can be easily grasped. The folding assembly strategy is a promising method to design and fabricate soft robots with complex configurations to complete tough tasks in harsh environments.

18.
Chemosphere ; 338: 139547, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37467856

RESUMO

Multi-carbon air pollutants pose serious hazards to the environment and health, especially soot and volatile organic compounds (VOCs). Catalytic oxidation is one of the most effective technologies for eliminating them. The oxidation of soot and most hydrocarbon VOCs begins with C-H (or edge-CH) activation, so this commonality can be targeted to design active sites. Rationally designed interface nanostructures optimize metal-support interactions (MSIs), providing suitable active sites for C-H activation. Meanwhile, the interfacial reactant spillover facilitates the further decomposition of activated intermediates. Thus, rationally exploiting interfacial effects is critical to enhancing catalytic activity. In this review, we analyzed recent advances in the following aspects: I. Understanding of the interface effects and design; II. Optimization of the catalyst-reactant contact, metal-support interface, and MSIs; III. Design of the interfacial composition and perimeter. Based on the analysis of the advances and current status, we provided challenges and opportunities for the rational design of interface nanostructures and interface-related stability. Meanwhile, a critical outlook was given on the interfacial sites of single-atom catalysts (SACs) for specific activation and catalytic selectivity.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/química , Carbono , Fuligem , Oxirredução , Metais/química , Compostos Orgânicos Voláteis/química , Catálise
19.
ACS Appl Mater Interfaces ; 15(50): 58976-58983, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38062569

RESUMO

We present a novel iontronic barometric pressure sensor based on a gel polymer electrolyte and interdigital electrodes with a much simpler structure than that of existing devices. By introducing high-density microstructures on the gel polymer electrolyte and one side electrode arrangement configuration, the developed sensor offers high performances with an ultrahigh resolution of 10 Pa, an ultrawide barometric pressure-response range from -92 to 7 kPa, a fast response time of ∼15 ms, and excellent long-term stability. The single pressure sensor is able to detect positive and negative barometric pressures without needing any additional means and can operate as a barometric altimeter with a resolution of about one-floor height. The performances of the sensors significantly surpass those of existing barometric pressure sensors. This work provides a new strategy for making high-performance barometric pressure sensors that are highly sought for commercial applications such as altitude detection, negative pressure ambulance, and consumer electronics.

20.
Mil Med Res ; 10(1): 15, 2023 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-36949519

RESUMO

BACKGROUND: Reconstruction of damaged tissues requires both surface hemostasis and tissue bridging. Tissues with damage resulting from physical trauma or surgical treatments may have arbitrary surface topographies, making tissue bridging challenging. METHODS: This study proposes a tissue adhesive in the form of adhesive cryogel particles (ACPs) made from chitosan, acrylic acid, 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS). The adhesion performance was examined by the 180-degree peel test to a collection of tissues including porcine heart, intestine, liver, muscle, and stomach. Cytotoxicity of ACPs was evaluated by cell proliferation of human normal liver cells (LO2) and human intestinal epithelial cells (Caco-2). The degree of inflammation and biodegradability were examined in dorsal subcutaneous rat models. The ability of ACPs to bridge irregular tissue defects was assessed using porcine heart, liver, and kidney as the ex vivo models. Furthermore, a model of repairing liver rupture in rats and an intestinal anastomosis in rabbits were established to verify the effectiveness, biocompatibility, and applicability in clinical surgery. RESULTS: ACPs are applicable to confined and irregular tissue defects, such as deep herringbone grooves in the parenchyma organs and annular sections in the cavernous organs. ACPs formed tough adhesion between tissues [(670.9 ± 50.1) J/m2 for the heart, (607.6 ± 30.0) J/m2 for the intestine, (473.7 ± 37.0) J/m2 for the liver, (186.1 ± 13.3) J/m2 for muscle, and (579.3 ± 32.3) J/m2 for the stomach]. ACPs showed considerable cytocompatibility in vitro study, with a high level of cell viability for 3 d [(98.8 ± 1.2) % for LO2 and (98.3 ± 1.6) % for Caco-2]. It has comparable inflammation repair in a ruptured rat liver (P = 0.58 compared with suture closure), the same with intestinal anastomosis in rabbits (P = 0.40 compared with suture anastomosis). Additionally, ACPs-based intestinal anastomosis (less than 30 s) was remarkably faster than the conventional suturing process (more than 10 min). When ACPs degrade after surgery, the tissues heal across the adhesion interface. CONCLUSIONS: ACPs are promising as the adhesive for clinical operations and battlefield rescue, with the capability to bridge irregular tissue defects rapidly.


Assuntos
Adesivos , Adesivos Teciduais , Ratos , Humanos , Suínos , Coelhos , Animais , Criogéis , Células CACO-2 , Inflamação
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