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Hydrogels have been widely used in various fields due to their diverse properties and flexible preparation methods. However, limited by the open network structure, hydrogels inevitably lose water in air or absorb water in aqueous solution, resulting in the loss of intrinsic functions, which severely hinders their practical applications. To address this issue, a general strategy was developed by subsequently modifying the surface of hydrogels with branched polyethyleneimine (PEI) and (3-(methacryloxy)propyl)trimethoxysilane (MPS) to covalently construct a dense cross-linked siloxane layer on the hydrogel surface. As a proof of concept, poly(2-(dimethylamino)ethyl methacrylate)/sodium alginate (PDMAEMA/SA) hydrogels were chosen as the model hydrogels to verify the feasibility of this strategy. The hydrogels adsorbed PEI to form amino-rich surfaces through hydrogen bonding, followed by covalently grafting MPS through rapid and catalyst-free mutual chemical reactions between acrylates and amine groups, as well as the hydrolysis of MPS. After modification, robust hydrophobic surfaces were successfully fabricated on the hydrophilic hydrogels. The modified hydrogels exhibited extraordinary anti-swelling and water-retention abilities. As the most typical intrinsic properties of hydrogels, the conductivity and sensing performance were well preserved. The strategy reported here provides a new insight into the construction of hydrogels with anti-swelling and water-retention abilities.
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With the development of flexible and wearable electronic devices, it is a new challenge for polymer hydrogel electrolytes to combine high mechanical flexibility and electrochemical performance into one membrane. In general, the high content of water in hydrogel electrolyte membranes always leads to poor mechanical strength, and limits their applications in flexible energy storage devices. In this work, based on the "salting out" phenomenon in Hofmeister effect, a kind of gelatin-based hydrogel electrolyte membrane is fabricated with high mechanical strength and ionic conductivity by soaking pre-gelated gelatin hydrogel in 2 m ZnSO4 aqueous. Among various gelatin-based electrolyte membranes, the gelatin-ZnSO4 electrolyte membrane delivers the "salting out" property of Hofmeister effect, which improves both the mechanical strength and electrochemical performance of gelatin-based electrolyte membranes. The breaking strength reaches 1.5 MPa. When applied to supercapacitors and zinc-ion batteries, it can sustain over 7500 and 9300 cycles for repeated charging and discharging processes. This study provides a very simple and universal method to prepare polymer hydrogel electrolytes with high strength, toughness, and stability, and its applications in flexible energy storage devices provide a new idea for the construction of secure and stable flexible and wearable electronic devices.
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Anisotropic conductive hydrogels mimicking the natural tissues with high mechanical properties and intelligent sensing have played an important role in the field of flexible electronic devices. Herein, tensile remodeling, drying, and subsequent ion cross-linking methods were used to construct anisotropic hydrogels, which were inspired by the orientation and functionality of tendons. Due to the anisotropic arrangement of the polymer network, the mechanical performance and electrical conductivity were greatly improved in specific directions. The tensile stress and elastic modulus of the hydrogel along the network orientation were 29.82 and 28.53 MPa, which were higher than those along the vertical orientation, 9.63 and 11.7 MPa, respectively. Moreover, the hydrogels exhibited structure-dependent anisotropic sensing. The gauge factors (GFs) parallel to the prestretching direction were greater than the GF along the vertical direction. Thus, the tendon-inspired conductive hydrogels with anisotropy could be used as flexible sensors for joint motion detection and voice recognition. The anisotropic hydrogel-based sensors are highly expected to promote the great development of emerging soft electronics and medical detection.
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"Fast-charging" lithium-ion batteries have gained a multitude of attention in recent years since they could be applied to energy storage areas like electric vehicles, grids, and subsea operations. Unfortunately, the excellent energy density could fail to sustain optimally while lithium-ion batteries are exposed to fast-charging conditions. In actuality, the crystal structure of electrode materials represents the critical factor for influencing the electrode performance. Accordingly, employing anode materials with low diffusion barrier could improve the "fast-charging" performance of the lithium-ion battery. In this Review, first, the "fast-charging" principle of lithium-ion battery and ion diffusion path in the crystal are briefly outlined. Next, the application prospects of "fast-charging" anode materials with various crystal structures are evaluated to search "fast-charging" anode materials with stable, safe, and long lifespan, solving the remaining challenges associated with high power and high safety. Finally, summarizing recent research advances for typical "fast-charging" anode materials, including preparation methods for advanced morphologies and the latest techniques for ameliorating performance. Furthermore, an outlook is given on the ongoing breakthroughs for "fast-charging" anode materials of lithium-ion batteries. Intercalated materials (niobium-based, carbon-based, titanium-based, vanadium-based) with favorable cycling stability are predominantly limited by undesired electronic conductivity and theoretical specific capacity. Accordingly, addressing the electrical conductivity of these materials constitutes an effective trend for realizing fast-charging. The conversion-type transition metal oxide and phosphorus-based materials with high theoretical specific capacity typically undergoes significant volume variation during charging and discharging. Consequently, alleviating the volume expansion could significantly fulfill the application of these materials in fast-charging batteries.
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Antimony selenide (Sb2Se3) is emerging as a promising photovoltaic material owing to its excellent photoelectric property. However, the low carrier transport efficiency, and detrimental surface oxidation of the Sb2Se3 thin film greatly influenced the further improvement of the device efficiency. In this study, the introduction of tellurium (Te) can induce the benign growth orientation and the desirable Sb/Se atomic ratio in the Te-Sb2Se3 thin film. Under various characterizations, it found that the Te-doping tended to form Sb2Te3-doped Sb2Se3, instead of alloy-type Sb2(Se,Te)3. After Te doping, the mitigation of surface oxidation has been confirmed by the Raman spectra. High-quality Te-Sb2Se3 thin films with preferred [hk1] orientation, large grain size, and low defect density can be successfully prepared. Consequently, a 7.61% efficiency Sb2Se3 solar cell has been achieved with a VOC of 474 mV, a JSC of 25.88 mA/cm2, and an FF of 64.09%. This work can provide an effective strategy for optimizing the physical properties of the Sb2Se3 absorber, and therefore the further efficiency improvement of the Sb2Se3 solar cells.
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A mild and efficient method for direct C-H monofluoroalkylation of heteroarenes with easily accessible and inexpensive α-fluorocarboxylic acids has been developed. This silver-catalyzed reaction affords mono- and bis-monofluoroalkylated heteroarenes in good yields under mild conditions, and the solvent effect on the monofluoroalkylation reaction is discussed in detail.
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In recent years, the generation of a large amount of construction and demolition waste (CDW) has threatened the public environment and human health. The inefficient supply chain of CDW resource utilization hinders the green development of countries around the world, including China. This study aims to reveal the impact of information sharing regarding recyclers' market demand forecast on the performance of CDW resource utilization supply chains. Therefore, this paper uses the incomplete information dynamic game method to establish and solve the decision-making model of the construction and demolition waste resource utilization supply chain under the conditions of recyclers sharing and not sharing their information. The paper then obtains the Bayesian equilibrium solution and the optimal expected profit for each party. Finally, a numerical simulation was used in order to verify the validity of the model and conclusions. The main conclusions are as follows. In the CDW resource utilization supply chain, if the recycler is more pessimistic about the market's demand forecast, their information sharing makes the remanufacturer more motivated to improve their level of environmental responsibility. In addition, information sharing by recyclers is always beneficial in increasing the profit of the remanufacturer, but it also may make the recycler lose profit. When the efficiency of the environmental responsibility investment of remanufacturers is in a high range, information sharing increases the profits of recyclers. Conversely, information sharing has no significant effect on the profits of recyclers. The impact on the profits of the entire CDW resource utilization supply chain depends on the intensity of competition among channels, the market share of offline recycling channels and the efficiency of environmental responsibility investments.
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Industria de la Construcción , Administración de Residuos , Teorema de Bayes , China , Materiales de Construcción , Humanos , Residuos Industriales , Difusión de la Información , Reciclaje/métodos , Administración de Residuos/métodosRESUMEN
As a specific biomarker, neuron-specific enolase (NSE) is an essential clinical indicator for diagnosing small cell lung cancer. In this paper, a sandwich-type electrochemical immunosensor was designed for the quantitative detection of NSE. AuPt nanoblock spherical nanoarchitectonics (AuPt NSNs), a bimetallic nanoparticle with a rugged morphology, were utilized as the substrate, which could enhance the electronic conduction and increase the immobilization capacity of the primary antibody (Ab1). Moreover, through a simple hydrothermal method, Au/CuxO@CeO2 was prepared as a spiny core-shell nanocube with cerium dioxide (CeO2) and gold nanoparticles (Au NPs) loading. The combination of Cu2O, CuO, and CeO2 showed favorable catalytic activity toward hydrogen peroxide (H2O2). Furthermore, the deposition of Au NPs on the spiny surface structure enhanced the specific surface area and biocompatibility, thereby rendering it more effective for loading the second antibody (Ab2). As the label material, the Au/CuxO@CeO2 achieved signal amplification and sensitive detection with the immunosensor. Under optimal conditions, the designed immunosensor possessed a broad linear range of 50 fg mL-1 to 100 ng mL-1 and a limit of detection of 31.3 fg mL-1, along with satisfactory performance in sensitivity, selectivity, and stability.
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Técnicas Biosensibles/métodos , Cerio/química , Oro/química , Límite de Detección , Nanoestructuras/química , Neuronas/enzimología , Fosfopiruvato Hidratasa/metabolismo , Anticuerpos Inmovilizados/química , Electroquímica , Peróxido de Hidrógeno/química , Modelos Lineales , Nanopartículas del Metal/químicaRESUMEN
CONTEXT: Release of two drugs safely and independently should be necessary in medical or reaction engineering fields to overcome many complex problems such as multi-drug resistance in treatment of disease. OBJECTIVES: Core-shell structural microparticles that can load/release two drugs simultaneously are designed and prepared. MATERIALS: The microparticles are composed of mesoporous silica core and hyaluronate (HA)/poly (N-isopropylacrylamide) hybrid gel shell. METHODS: The synthesis processes are monitored by powder x-ray diffraction and Fourier transform infrared spectroscopy. The properties of microparticles are characterized by nuclear magnetic resonance, dynamic light scattering and transmission electron microscope methods. Two kinds of drugs are loaded into the mesoporous-core and gel-shell, respectively, and then released under various conditions. RESULTS: The microparticles show uniform spherical shapes with core-shell structures. When temperature is higher than the lower critical solution temperature, the microparticles shrink abruptly and assemble. The drug release rates have been found to depend on the concentration of the microparticle suspensions and pH of the release medium. DISCUSSION: The swellability of the microparticles are controlled by the HA size and gel crosslink density; and the main effect factors on drug releasing behavior are the drug properties and drug diffusion ability. CONCLUSION: The experimental results confirmed different drugs could be safely loaded into the core-shell structural microparticles and released independently, which might be potential carriers for drugs or catalysts. These microparticles would be expected to make sense for applying in medical or reaction engineering fields.