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1.
Int J Biol Macromol ; : 133748, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38986996

RESUMEN

Poly-L-lactic acid (PLLA), recognized as a piezoelectric material, not only demonstrates exceptional piezoelectric properties but also exhibits commendable biocompatibility and biodegradability. These properties render PLLA highly promising for diverse applications, including sensors, wearable devices, biomedical engineering, and related domains. This review offers a comprehensive overview of the distinctive piezoelectric effect of PLLA-based material and delves into the latest advancements in its preparation strategies as a piezoelectric material. It further presents recent research progress in PLLA-based piezoelectric materials, particularly in the realms of health monitoring, skin repair, nerve regeneration, and tissue repair. The discourse extends to providing insights into potential future trajectories for the development of PLLA-based piezoelectric materials.

2.
Sci Technol Adv Mater ; 25(1): 2362125, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38882257

RESUMEN

Polymeric materials can boost their performances by strategically incorporating inorganic substances. Heat dissipators are a representative class of such composite materials, where inorganic fillers and matrix polymers contribute to high thermal conductivity and strong adhesion, respectively, resulting in excellent heat dissipation performance. However, due to the complex interaction between fillers and polymers, even slight differences in structural parameters, e.g. dispersion/aggregation degree of fillers and crosslink density of polymers, may significantly impact material performance, complicating the quality management and guidelines for material developments. Therefore, we introduce pyrolysis mass spectra (MS) as material descriptors. On the basis of these spectra, we construct prediction models using a data-driven approach, specifically focusing on thermal conductivity and adhesion, which are key indicators for heat dissipating performance. Pyrolysis-MS observes thermally decomposable polymers, which occupy only 0.1 volume fraction of the heat dissipators; nevertheless, the physical states of non-decomposable inorganic fillers are implicitly reflected in the pyrolyzed fragment patterns of the matrix polymers. Consequently, pyrolysis-MS provides sufficient information to construct accurate models for predicting heat dissipation performance, simplifying quality management by substituting time-consuming performance evaluations with rapid pyrolysis-MS measurements. Furthermore, we elucidate that higher crosslinking density of the matrix polymers enhances thermal conductivity. This data-driven method promises to streamline the identification of key functional factors in complex composite materials.


Using pyrolysis-MS as a material descriptor allows for the prediction of composite materials' heat dissipation capabilities and the identification of key factors influencing these properties.

3.
Polymers (Basel) ; 16(11)2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38891558

RESUMEN

When the cocoa pod husk (CPH) is used and processed, two types of flour were obtained and can be differentiated by particle size, fine flour (FFCH), and coarse flour (CFCH) and can be used as a possible reinforcement for the development of bio-based composite materials. Each flour was obtained from chopping, drying by forced convection, milling by blades, and sieving using the 100 mesh/bottom according to the Tyler series. Their physicochemical, thermal, and structural characterization made it possible to identify the lower presence of lignin and higher proportions of cellulose and pectin in FFCH. Based on the properties identified in FFCH, it was included in the processing of thermoplastic starch (TPS) from the plantain pulp (Musa paradisiaca) and its respective bio-based composite material using plantain peel short fiber (PPSF) as a reinforcing agent using the following sequence of processing techniques: extrusion, internal mixing, and compression molding. The influence of FFCH contributed to the increase in ultimate tensile strength (7.59 MPa) and higher matrix-reinforcement interaction when obtaining the freshly processed composite material (day 0) when compared to the bio-based composite material with higher FCP content (30%) in the absence of FFCH. As for the disadvantages of FFCH, reduced thermal stability (323.57 to 300.47 °C) and losses in ultimate tensile strength (0.73 MPa) and modulus of elasticity (142.53 to 26.17 MPa) during storage progress were identified. In the case of TPS, the strengthening action of FFCH was not evident. Finally, the use of CFCH was not considered for the elaboration of the bio-based composite material because it reached a higher lignin content than FFCH, which was expected to decrease its affinity with the TPS matrix, resulting in lower mechanical properties in the material.

4.
Sci Rep ; 14(1): 13261, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38858469

RESUMEN

Predicting and optimizing the mechanical performance of the helically wound nylon-reinforced rubber fertilizer hose (HWNR hose) is crucial for enhancing the performance of hose pumps. This study aims to enhance the service life of HWNR hoses and the efficiency of liquid fertilizer transport. First, a finite element simulation model and a mathematical model were established to analyze the influence of fiber layer arrangement on the maximum shear strain on the coaxial surface (MSS) and the reaction force on the extrusion roller (RF). For the first time, the Crested Porcupine Optimizer algorithm was used to improve the Generalized Regression Neural Network (CPO-GRNN) method to establish a surrogate model for predicting the mechanical properties of HWNR hoses, and it was compared with Response Surface Methodology (RSM). Results showed CPO-GRNN's superiority in handling complex nonlinear problems. Finally, the Non-dominated Sorting Genetic Algorithm II (NSGA-II) was employed for optimization design. Compared to the original HWNR hose with an MSS of 0.906 and an RF of 30,376N, the optimized design reduced the MSS by 7.99% and increased the RF by 2.46%, significantly enhancing their service life and liquid fertilizer transport capacity. However, further research on fatigue damage is needed.

5.
Ultrasonics ; 141: 107333, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38692213

RESUMEN

With the increasing utilization of composite materials due to their superior properties, the need for efficient structural health monitoring techniques rises rapidly to ensure the integrity and reliability of composite structures. Deep learning approaches have great potential applications for Lamb wave-based damage detection. However, it remains challenging to quantitatively detect and characterize damage such as delamination in multi-layered structures. These deep learning architectures still lack a certain degree of physical interpretability. In this study, a convolutional sparse coding-based UNet (CSCUNet) is proposed for ultrasonic Lamb wave-based damage assessment in composite laminates. A low-resolution image is generated using delay-and-sum algorithm based on Lamb waves acquired by transducer array. The encoder-decoder framework in the proposed CSCUNet enables the transformation of low-resolution input image to high-resolution damage image. In addition, the multi-layer convolutional sparse coding block is introduced into encoder of the CSCUNet to improve both performance and interpretability of the model. The proposed method is tested on both numerical and experimental data acquired on the surface of composite specimen. The results demonstrate its effectiveness in identifying the delamination location, size, and shape. The network has powerful feature extraction capability and enhanced interpretability, enabling high-resolution imaging and contour evaluation of composite material damage.

6.
J Dent ; 146: 105031, 2024 07.
Artículo en Inglés | MEDLINE | ID: mdl-38710315

RESUMEN

OBJECTIVES: To investigate and compare the chemical and optical stability of four restorative composite materials: two injectable resins, one flowable resin and one compomer. METHODS: Two injectable nano-filled composite resins: G-aenial Universal (GU) and Beautifil Injectable XSL (BI), a flowable composite resin: Filtek Supreme Flowable (FS) and a compomer: Dyract Flow (DF), in A2 shade were tested and compared. Water sorption and solubility were conducted according to ISO4049:2019 standard; ICP-OES and F-ion selective electrode were used to test the elemental release; Degree of conversion (DC) was obtained by using FTIR; water contact angle was obtained by static sessile drop method, and a spectrophotometer was used for optical properties (ΔE⁎, ΔL⁎ and TP). SPSS 28.0 was used for statistical analysis and the significant level was pre-set as α = 0.05. RESULTS: GU performed the best in water sorption and solubility, FS had the lowest elemental release, the best colour stability, and the highest DCIM and DC24-h. DF, the compomer had the lowest, and GU and BI, the injectable composites had the largest water contact angle, respectively. Correlations were found between water sorption and water solubility. CONCLUSIONS: The four composite restorative materials showed different chemical and optical behaviours. Overall, composite resins performed better than compomer, while additional laboratory and in vivo tests are necessary to obtain a more comprehensive comparison between injectable and flowable composite resins. Wsp and Wsl are influenced by many common factors, and the values are highly positively related. CLINICAL SIGNIFICANCE: A comprehensive understanding of materials is crucial before selecting materials for clinical practice. Composite resins rather than compomers are recommended because of their exceptional properties, which make them eligible for a wide range of clinical applications and an elongated lifespan.


Asunto(s)
Color , Compómeros , Resinas Compuestas , Materiales Dentales , Ensayo de Materiales , Solubilidad , Agua , Resinas Compuestas/química , Materiales Dentales/química , Agua/química , Compómeros/química , Humanos , Restauración Dental Permanente/métodos , Espectrofotometría , Espectroscopía Infrarroja por Transformada de Fourier , Metacrilatos/química , Inyecciones , Poliuretanos/química , Nanocompuestos/química , Propiedades de Superficie , Fenómenos Ópticos , Bisfenol A Glicidil Metacrilato
7.
Int J Biol Macromol ; 270(Pt 1): 132190, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38723820

RESUMEN

This study describes the synthesis of Chitosan - corn protein (CSZ-TG) composites using TG enzyme (TG) as a cross-linking agent and the preparation of chitosan-based composite membrane material (CSZEO-TG) by blending citrus essential oil (EO) with the synthesized CSZ-TG. The prepared composite membrane material was used for fresh strawberry preservation and characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-spectral diffraction, tensile properties, and water vapor and CO2 permeability. Scanning electron microscopy results showed a smooth surface of the composite membrane material after the addition of TG enzyme, while Fourier transforms infrared spectroscopy results showed a structural change of the composite membrane material after the addition of corn protein (Z). The tensile results showed an increase in the tensile strength of the composite membrane material after the addition of TG enzyme, while the flexibility of the composite membrane material was enhanced after the addition of EO. Compared with the pure chitosan membrane (CS), the water vapor and CO2 barrier properties of the composite membrane material after the addition of Z, TG, and EO did not change much, and they all showed better water vapor barrier properties. The results of the antioxidant analysis of the solution of the CSZEO-TG composite membrane material showed that the composite membrane material had efficient antioxidant properties. The effects of the composite film material on the storage period and quality of strawberries were evaluated by the indicators of weight loss, hardness, decay rate, soluble solids, titratable acid content, MDA content, and the content of four enzymes, SOD, POD, PPO and CAT. Comprehensive freshness data analysis showed that CSZEO-TG had the best freshness preservation performance and effectively extended the shelf life of strawberries.


Asunto(s)
Quitosano , Fragaria , Zea mays , Quitosano/química , Fragaria/química , Fragaria/enzimología , Zea mays/química , Resistencia a la Tracción , Antioxidantes/química , Antioxidantes/farmacología , Proteínas de Plantas/química , Conservación de Alimentos/métodos , Vapor , Permeabilidad , Dióxido de Carbono/química , Espectroscopía Infrarroja por Transformada de Fourier , Aceites Volátiles/química
8.
Talanta ; 276: 126238, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38761655

RESUMEN

Facing with the difficulty of specific chromatographic separation of nucleoside drugs, this study prepared a surface molecularly imprinted polymer (SMIP) modified covalent organic framework (COF) coated silica stationary phase based on the specificity of molecular imprinting technology and the powerful chromatographic separation performance of COF. This novel SMIP-COF@SiO2 stationary phase can not only specifically identify template molecule and structural analogs, but can also be used to separate multiple types of analytes, such as B vitamins, sulfonamides, alkylbenzenes, phenyl ketones, polycyclic aromatic hydrocarbons and environmental endocrine disruptors, which satisfies the need for complex sample separation. Various retention mechanisms have been investigated and multiple interactions between the SMIP-COF@SiO2 stationary phase and the analytes are discovered. The chromatographic performance of SMIP-COF@SiO2 is far superior to that of the SMIP@SiO2 and COF@SiO2. Furthermore, the SMIP-COF@SiO2 stationary phase can be successfully used to analyze polycyclic aromatic hydrocarbons in the environmental water sample and detect whitening ingredient in skincare product, indicating its great potential for application in various fields.

9.
Materials (Basel) ; 17(9)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38730922

RESUMEN

Hybrid bonded-bolted composite material interference connections significantly enhance the collaborative load-bearing capabilities of the adhesive layer and bolts, thus improving structural load-carrying capacity and fatigue life. So, these connections offer significant developmental potential and application prospects in aircraft structural assembly. However, interference causes damage to the adhesive layer and composite laminate around the holes, leading to issues with interface damage. In this study, we employed experimental and finite element methods. Initially, different interference-fit sizes were selected for bolt insertion to analyze the damage mechanism of the adhesive layer during interference-fit bolt installation. Subsequently, a finite element tensile model considering damage to the adhesive layer and composite laminate around the holes post-insertion was established. This study aimed to investigate damage in composite bonded-bolted hybrid joints, explore load-carrying rules and failure modes, and reveal the mechanisms of interference effects on structural damage and failure. The research results indicate that the finite element prediction model considering initial damage around the holes is more effective. As the interference-fit size increases, damage to the adhesive layer transitions from surface debonding to local cracking, while damage to the composite matrix shifts from slight compression failure to severe delamination and fiber-bending fracturing. The structural strength shows a trend of initially increasing and then decreasing, with the maximum strength observed at an interference-fit size of 1.1%.

10.
Polymers (Basel) ; 16(9)2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38732692

RESUMEN

This research work is based on a previous study by the authors that characterized the behavior of FBG sensors with a polyimide coating in a structural monitoring system. Sensors applied to structural health monitoring are affected by the presence of simultaneous multidirectional strains. The previous study observed the influence of the transverse strain (εy) while keeping the longitudinal strain constant (εx), where the x direction is the direction of the optical fiber. The present study develops an experimental methodology consisting of a biaxial test plan on cruciform specimens with three embedded FBG sensors coated with polyimide, acrylate, and ORMOCER®. Applying the Strain-Optic Theory as a reference, a comparison of the experimental values obtained with the different coatings was studied. This experimental work made it possible to study the influence of the transverse strain (εy) on the longitudinal measurements of each FBGS and the influence of the coating material. Finally, the calibration procedure was defined as well as K (strain sensitivity factor) for each sensor.

11.
Chemphyschem ; : e202400154, 2024 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-38798029

RESUMEN

Turning waste into valuable products is one of the main challenges of the chemical industry. In this work, chitosan (CS), an abundant, low-cost, and non-toxic biopolymer derived from chitin, was reshaped into beads of ~ 3 mm. Their suitability as a support material for active phase catalyst materials was tested for a zirconium-based Metal-Organic Framework (MOF) with incorporated Pt, namely UiO-67-Pt. Its incorporation was investigated via two procedures: a one-pot synthesis (OPS) and a post-synthetic functionalization (PSF) synthesis method. Scanning electron microscopy (SEM) images show good UiO-67-Pt dispersion throughout the CS beads for the one-pot synthesized material (UiO-67-Pt-OPS@CS). However, this uniform dispersion was not observed for the post-synthetically functionalized material (UiO-67-Pt-PSF@CS). The success of the implementation of UiO-67-Pt was evaluated with ultraviolet-visible and infrared spectroscopy for both composite materials. Thermogravimetric analysis reveals higher thermal stabilities for UiO-67-Pt-OPS@CS composite beads in comparison to pure CS beads, but not for UiO-67-Pt-PSF@CS. The study provides valuable insights into the potential of chitosan as a green, bead-shaped support material for MOFs, offering flexibility in their incorporation through different synthesis routes. It further contributes to the broader goal of the sustainable and eco-friendly design of a new generation of catalysts made from waste materials.

12.
Bioengineering (Basel) ; 11(5)2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38790281

RESUMEN

Anterior cruciate ligament (ACL) ruptures are prevalent knee injuries, with approximately 200,000 ruptures annually, and treatment costs exceed USD two billion in the United States alone. Typically, the initial detection of ACL tears and anterior tibial laxity (ATL) involves manual assessments like the Lachman test, which examines anterior knee laxity. Partial ACL tears can go unnoticed if they minimally affect knee laxity; however, they will progress to a complete ACL tear requiring surgical treatment. In this study, a computational finite element model (FEM) of the knee joint was generated to investigate the effect of partial ACL tears under the Lachman test (GNRB® testing system) boundary conditions. The ACL was modeled as a hyperelastic composite structure with a refined representation of collagen bundles. Five different tear types (I-V), classified by location and size, were modeled to predict the relationship between tear size, location, and anterior tibial translation (ATT). The results demonstrated different levels of ATT that could not be manually detected. Type I tears demonstrated an almost linear increase in ATT, with the growth in tear size ranging from 3.7 mm to 4.2 mm, from 25% to 85%, respectively. Type II partial tears showed a less linear incline in ATT (3.85, 4.1, and 4.75 mm for 25%, 55%, and 85% partial tears, respectively). Types III, IV, and V maintained a nonlinear trend, with ATTs of 3.85 mm, 4.2 mm, and 4.95 mm for Type III, 3.85 mm, 4.25 mm, and 5.1 mm for Type IV, and 3.6 mm, 4.25 mm, and 5.3 mm for Type V, for 25%, 55%, and 85% partial tears, respectively. Therefore, for small tears (25%), knee stability was most affected when the tears were located around the center of the ligament. For moderate tears (55%), the effect on knee stability was the greatest for tears at the proximal half of the ACL. However, severe tears (85%) demonstrated considerable growth in knee instability from the distal to the proximal ends of the tissue, with a substantial increase in knee instability around the insertion sites. The proposed model can enhance the characterization of partial ACL tears, leading to more accurate preliminary diagnoses. It can aid in developing new techniques for repairing partially torn ACLs, potentially preventing more severe injuries.

13.
Sci Rep ; 14(1): 12083, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38802453

RESUMEN

In this paper, Voronoi cell finite element method (VCFEM) based on assumed flux hybrid formulation has been presented for heat conduction problem of particle reinforced composites material. The heat fluxes satisfying a priori internal thermal balance are directly approximated independently in the matrix and the inclusion respectively. The temperatures on element boundary and matrix-inclusion interface are interpolated by nodal temperature. The thermal balance on the interelement boundary and matrix-inclusion interface is relaxed and introduced into the functional by taking the temperature as Lagrange multiplier. In this way, a functional containing two variables of heat flux and temperature is proposed. Full field heat flux and effective thermal conductivity are obtained. Feasibility and effectiveness of the proposed approach are verified through several numerical examples.

14.
Materials (Basel) ; 17(3)2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38591449

RESUMEN

In the present study, a piecewise-integrated composite bumper beam for passenger cars is proposed, and the design innovation process for a composite bumper beam regarding a bumper test protocol suggested by the Insurance Institute for Highway Safety is carried out with the help of machine learning models. Several elements in the bumper FE model have been assigned to be references in order to collect training data, which allow the machine learning model to study the method of predicting loading types for each finite element. Two-dimensional and three-dimensional implementations are provided by machine learning models, which determine the stacking sequences of each finite element in the piecewise-integrated composite bumper beam. It was found that the piecewise-integrated composite bumper beam, which is designed by a machine learning model, is more effective for reducing the possibility of structural failure as well as increasing bending strength compared to the conventional composite bumper beam. Moreover, the three-dimensional implementation produces better results compared with results from the two-dimensional implementation since it is preferable to choose loading-type information, which is achieved from surroundings when the target elements are located either at corners or junctions of planes, instead of using information that comes from the identical plane of target elements.

15.
Chemosphere ; 362: 142144, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38677615

RESUMEN

Materials from green resources boast a low carbon footprint, forming the foundation of the circular economy approach in materials science. Thus, in this study, waste poly(ethylene terephthalate) (PET) was subjected to depolymerization using propylene glycol (PG), and subsequent polycondensation with bio-based maleic anhydride (MA) produced unsaturated polyester resin (b-UPR). Bio-derived acryloyl-modified Kraft lignin (KfL-A) served as a vinyl reactive filler in the b-UPR matrix to create b-UPR/KfL-A composites. The structural characterization of KfL-A and b-UPR involved the use of FTIR and NMR techniques. The mechanical properties of the newly fabricated composites were assessed through tensile strength, Vickers microhardness, and dynamic mechanical tests. The addition of KfL-A to the rigid b-UPR matrix enhanced material flexibility, resulting in less stiff and hard materials while preserving composite toughness. For instance, incorporating 10 wt% of KfL-A in b-UPR led to a 17% reduction in hardness, a 48% decrease in tensile strength, and a 20% reduction in toughness. Positive environmental impact was achieved by incorporation of 64 wt% of renewable and recycled raw material. Analogously prepared b-UPR/KfL composites showed structural inhomogeneity and somewhat better mechanical properties. Transmission (TEM) and scanning (SEM) electron microscopies revealed a suitable relationship between mechanical and structural properties of composites in relation to the extent of KfL-A addition. The UL94V flammability rating confirmed that flame resistance increased proportionally with the KfL-A addition. Once deposited in a landfill, these composites are expected to disintegrate more easily than PET, causing less harm to the environment and contributing to sustainability in the plastics cycle.

16.
Polymers (Basel) ; 16(8)2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38674953

RESUMEN

This study presents an analysis of films which consist of two layers; one layer is PVDF as the matrix, along with fillers BaTiO3 (BT), and the second is one bacterial nanocellulose (BNC) filled with Fe3O4. The mass fraction of BT in PVDF was 5%, and the samples were differentiated based on the duration of the mechanical activation of BT. This innovative PVDF laminate polymer with environmentally friendly fillers aligns with the concept of circular usage, resulting in a reduction in plastic content and potential improvement of the piezoelectric properties of the entire composite. This work presents new, multifunctional "green" packaging materials that potentially could be a good alternative to specific popular materials used for this purpose. The synthesis of the films was carried out using the hot press method. Tensile tests, water vapor permeability examination, and structural analyses using SEM-EDS and FTIR have been conducted. The sample PVDF/BT20/BNC/Fe3O4 exhibited the best barrier properties (impermeability to water vapor), while the highest tensile strength and toughness were exhibited by the PVDF/BT5/BNC/Fe3O4 sample.

17.
Materials (Basel) ; 17(7)2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38611967

RESUMEN

In this paper, the glass-fiber-fabric-reinforced resin-based absorbing composites were prepared, and their microwave-absorbing properties were studied via simulation and experiment. The simulation results show that the absorption bandwidth of the absorbing material can cover the X\C\S band, respectively, at different thicknesses. The minimum reflection loss (RL) of the composite with a thickness of 2.2 mm is -27.4 dB at 5.95 GHz. However, the experiment results are quite different from those of the simulation. The metallographic results indicate that it is the change of the mass fraction of the absorbents in the composites after curing that causes the difference. According to the metallographic results, three shape approximation methods were proposed to calculate the real mass ratio of the absorbents in the composites, namely, parallelogram approximation, bows approximation, and elliptical approximation. Meanwhile, the structural parameter Kf was introduced to optimize the calculation results. The electromagnetic parameters of the material based on the calculation results were measured, and the results show that the simulation results obtained via bow approximation have a better coincidence to the experiment results, and the mass ratio of the absorbent raises by around 9.95%, which lays a foundation for the subsequent design of microwave-absorbing composites.

18.
Materials (Basel) ; 17(8)2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38673277

RESUMEN

This paper focuses on the preparation and evaluation of a novel humidity-control material, vermiculite/(sodium polyacrylate(AA)-acrylamide(AM)), using inverse suspension polymerization. Acrylic acid and acrylamide were introduced into the interlayer of modified vermiculite during the polymerization process, leading to the formation of a strong association with the modified vermiculite. The addition of vermiculite increased the specific surface area and pore volume of the composites. To investigate the moisture absorption and desorption properties of the composites, an orthogonal experiment and single-factor experiment were conducted to analyze the impacts of vermiculite content, neutralization degree, and the mass ratio of AA to AM. According to the control experiment, the addition of vermiculite was found to enhance the pore structure and surface morphology of the composite material, surpassing both vermiculite and PAA-AM copolymer in terms of humidity control capacity and rate. The optimal preparation conditions were identified as follows: vermiculite mass fraction of 4 wt%, a neutralization degree of 90%, and mAA:mAM = 4:1. The moisture absorption rate and moisture release rate of the composite material prepared under these conditions are 1.285 g/g and 1.172 g/g. The humidity control process of the composite material is governed by pseudo second-order kinetics, which encompasses the complete adsorption process. These results indicate that the vermiculite/PAA-AM composite humidity control material has excellent humidity control performance and is a simple and efficient humidity control method.

19.
ACS Appl Mater Interfaces ; 16(17): 22512-22521, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38651627

RESUMEN

Gold-sulfur interaction has vital importance in nanotechnologies and material chemistry to design functional nanoparticles, self-assembled monolayers, or molecular complexes. In this paper, a mixture of only two basic precursors, such as the chloroauric acid (HAu(III)Cl4) and a thiol molecule (p-fluorothiophenol (p-HSPhF)), are used for the synthesis of gold(I)-thiolate coordination polymers. Under different conditions of synthesis and external stimuli, five different functional materials with different states of [Au(I)(p-SPhF)]n can be afforded. These gold-thiolate compounds are (i) red emissive, flexible, and crystalline fibers; (ii) composite materials made of these red emissive fibers and gold nanoparticles; (iii) amorphous phase; (iv) transparent glass; and (v) amorphous-to-crystalline phase-change material associated with an ON/OFF switch of luminescence. The different functionalities of these materials highlight the great versatility of the gold(I) thiolate coordination polymers with easy synthesis and diverse shaping that may have great potential as sustainable phosphors, smart textiles, sensors, and phase change memories.

20.
Artículo en Inglés | MEDLINE | ID: mdl-38520148

RESUMEN

The cell's ability to change shape is a central feature in many cellular processes, including cytokinesis, motility, migration, and tissue formation. The cell constructs a network of contractile proteins underneath the cell membrane to form the cortex, and the reorganization of these components directly contributes to cellular shape changes. The desire to mimic these cell shape changes to aid in the creation of a synthetic cell has been increasing. Therefore, membrane-based reconstitution experiments have flourished, furthering our understanding of the minimal components the cell uses throughout these processes. Although biochemical approaches increased our understanding of actin, myosin II, and actin-associated proteins, using membrane-based reconstituted systems has further expanded our understanding of actin structures and functions because membrane-cortex interactions can be analyzed. In this review, we highlight the recent developments in membrane-based reconstitution techniques. We examine the current findings on the minimal components needed to recapitulate distinct actin structures and functions and how they relate to the cortex's impact on cellular mechanical properties. We also explore how co-processing of computational models with wet-lab experiments enhances our understanding of these properties. Finally, we emphasize the benefits and challenges inherent to membrane-based, reconstitution assays, ranging from the advantage of precise control over the system to the difficulty of integrating these findings into the complex cellular environment.

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