Search

In this study, a hydrogel composite adsorbent structure was reported and showed satisfactory adsorption performance. The study uses polylactic acid melt-blown nonwoven fabric to optimize and improve the adsorption performance of the hydrogel. The results show that the nonwoven fabric structure enables the composite material to reach the swelling equilibrium faster than the hydrogel. The adsorption-isotherm model found that the adsorption capacity of composite materials Pb(II) and Ni(II) reached 416.07 and 243.10 mg/g, respectively, and still had high removal efficiency at low pH. The composite material has low cost and can be reused, which solves the problems of difficulty in recovery of the hydrogel adsorbent, low strength, and easy damage, and promotes the industrialization of the hydrogel as an adsorbent.

In this study, a hydrogel adsorbent was successfully synthesized using hydroxyapatite/acrylamide/β-cyclodextrin to adsorb heavy metal ions and dyes in water. In the study, different contents of hydroxyapatite were added to the hydrogel, and then the mechanical properties and adsorption properties of the material were studied. The results show that the compressive strength of hydrogel added with hydroxyapatite increased by 37.1%. According to the adsorption isotherm model, the maximum adsorption capacity is 300mg/g. In addition, the preparation process of the composite hydrogel is simple, and can be used at a lower pH value, and can be used multiple times. Therefore, the material is of great significance to the treatment of pollutants.

In order to prepare a new high-performance and flexibility stab-resistant composite material, one type of high-toughness and high-strength hydrogel is combined with aramid fabric. In this paper, the nanocomposite (NC) hydrogels are prepared using Pluronic F127 Diacrylate (PF127DA) as the crosslinking agent, acrylamide as the monomer and nano-silica as nano additive. The influence of the addition amount of nano-silica on the toughness and strength of nano-composite hydrogels is discussed. The strength and toughness of the NC hydrogels with nano silica are higher than that of the acrylamide hydrogel without nano particles. The NC hydrogel with the best strength is made as a composite with aramid fabric and the effect of nanocomposite hydrogel on the stab resistance of the stab-resistant composite material is studied. The research shows that the stab resistance performance of the composite material prepared by aramid fabric and nanocomposite hydrogel is effectively improved in comparison with aramid fabric, and the yarn pulling force is also improved. The composite material with high stab resistance can be used as the stab-resistant layer of armor, cut-resistant gloves and stab-resistant base material of shoes. This work provided a possibility for preparing a kind of lightweight composite material with high stab resistance.

We fabricated the HfZrO2 (HZO) ferroelectric fin field-effect transistors (Fe-FinFET) with fin width of 60 nm and gate length of 100 nm for ferroelectric nonvolatile memory operations. The fabricated Fe-FinFET exhibited a large memory window (MW) of 1.5 V and high (100 ns) program/erase speeds at ±5 V. After $10^{{5}}$ program/erase cycles, the MW was maintained at 1.09 V and the retention time was measured up to $10^{{4}}$ s with no degradation. The fabricated HZO Fe-FinFET is compatible with the current FinFET process and has a high MW, a fast program/erase speed, and excellent reliability. Therefore, the fabricated Fe-FinFET is a promising candidate for high-density ferroelectric field-effect transistor memory applications.

In the work, a kind of composite material with excellent stab/puncture resistance was prepared by resin bonded Kevlar fabric. Water-borne epoxy resin (PAEK), polyacrylamide (APAM), fatty alcohol polyoxyethylene phosphate potassium salt (TFPK) are formulated to form a novel sizing agent that can be used for the sizing Kevlar fabrics. The effects of the sizing agent on the mechanical and stab/puncture resistance are examined. A field emission scanning electron microscopy (SEM), an ultra-depth of field 3d microscope, and a universal testing machine were used to observe and evaluate the morphology of sizing fabrics, the stab/puncture morphology, mechanical properties, and quasi-static stabbing properties, respectively. The test results show that the puncture resistance of the sizing Kevlar fabrics increases first and then decreases with the increase of sizing agent concentration. Compared with non-sizing fabrics, the Kevlar fabrics that are treated with a sizing agent at a concentration of 10 wt% have 524 % higher puncture resistance, 301 % higher stab resistance, and a 6.9-fold increase in the burst strength. Because the fiber bundles in the sizing fabrics are confined due to the resin saturation, the friction among fibers is enhanced and thus better resists an external force and contributes a greater resistance against sharp objects.

The Si-based n- and p-FeFET with 5-nm ferroelectric (FE) HfZrOx(HZO) and high-k AlON interfacial layer (IL) were fabricated for the comparison of memory characteristics and reliability. The memory window (MW) of 1.37 V and 1.25 V are obtained by the n- and p-FeFET respectively by applying pulses of ±3.8 V/ $50~\mu $ s. The typical MW asymmetry for both types of FeFETs is significantly reduced which is attributed to the reduced remanent polarization ( $\text{P}_{\text {r}}$ ) from the highly scaled HZO and the enhanced voltage drop across the HZO as well as the improved interfacial quality from the AlON IL. In addition, the p-FeFET demonstrates a MW of 1.02 V up to $10^{{5}}$ cycles with a long pulse $10^{-{4}}\text{s}$ , superior to that of the n-FeFET due to the mitigated hot-electrons induced hole generation. Furthermore, the p-FeFET shows comparable retention performance with the n-FeFET. These results indicate that the p-FeFET possesses the competence of future memory applications without adding process complexity and introducing new substrate material.

Epitaxial GeSn (epi-GeSn) shows the capability to form ferroelectric capacitors (FeCAPs) with a higher remanent polarization (Pr) than epi-Ge. With the interface engineering by a high-k AlON, the reliability of the epi-GeSn-based FeCAPs is enhanced. Using the highly reliable FeCAP in series with a resistor as the synapse and axon, a simplified neuromorphic network based on a differentiator circuit is proposed. The network not only holds the leaky integrate-and-fire (LIF) function but is also capable of recognizing the spatiotemporal features, which sets it apart from other LIF neurons arising from the FeCAP-modulated leaky behavior of the potential on the axon by spiking-time-dependent plasticity. Furthermore, it is more energy efficient to operate, nondestructive to read, and simpler to fabricate by employing FeCAPs, making it eligible for emergent spiking neural network hardware accelerators.

For the pursuit of conductive textiles with high electromagnetic shielding performance, specified yarns are processed with a special spinning feeding device with twist counts of 40 T, 50 T, 60 T, 70 T, 80 T, and 90 T, for Next, the optimal yarns from each group are made into SS/Pc-70 and Cu/Pc-80 conductive woven fabrics with a plain weave structure design. In addition, the surface resistivity, electromagnetic shielding effectiveness measurement and air permeability of the two conductive woven fabrics were tested and analyzed. Regarding the electromagnetic shielding performance test, the effects of the complete shielding network, the lamination layers of fabric, and lamination angle on the electromagnetic shielding performance are discussed. The test results indicate that Cu/Pc-80 woven fabrics has the lowest surface resistivity, which means it has the best electrical conductivity; Moreover, different types of metal wires provide the conductive fabrics with different levels of surface resistance. The variations in the lamination angles help attain a complete conductive network that significantly enhances the EMSE, and Cu/Pc-80 have a greater average shielding value comparatively and thus greater EMSE. For both types of conductive woven fabrics, one-layered conductive woven fabrics exhibit the maximal air permeability. As the air permeability of conductive woven fabrics is correlated with the thickness of fabrics, the greater the number of lamination layers, the lower the air permeability of the conductive fabrics.

Oil and organic pollutants removal becomes an efficient solution to dispose of industrial oily and textile dye wastewater. This study proposes a lotus leaf-like bionic nanofibrous membrane with underwater superoleophobic for highly efficient oil-water separation. Papillary structure of the bionic membrane is formed by electrospraying of PVDF and TiO2 solutions on the surface of beaded-structure PVDF/TiO2 membrane. Dopamine is then decorated on the resultant PVDF/TiO2 membrane by in situ polymerization to be with hydrophilic-underwater oleophobic property for highly efficient oil-water separation. This bionic membrane has > 99 % oil-water separation efficiency, and high flux of 1389 ± 67 L m−2 h−1. Its contact angle of underwater petroleum ether and dichlomethane reaches 155° and 152°, respectively. Moreover, it has excellent water transport capacity, photocatalytic property, as well as high separation efficiency and flux even after 5-cycle filtration. This bionic nanofibrous membrane will become a promising candidate in clean production, industrial oil/water separation, water purification and efficient liquid transmission.

TiN/amorphous HfO x /ferroelectric-HfZrO x (HZO)/TiN was explored to accomplish switchable diode behavior with desirable memory characteristics in terms of high ${R}_{{\mathrm {HRS}}}/{R}_{{\mathrm {LRS}}}$ ratio of ~2600 and retention up to ten years at 25 °C. The bias-controlled direction of the built-in diode was studied to be dominated by the polarization of HfZrO x while good retention can be achieved by stacking HfO x which is beneficial to suppress leakage current. More importantly, 16 Boolean functions can be realized in a single device which is easier to implement multiplier and adder. The prominent nonvolatile memory and computation performance make it a promising device for logic-in-memory (LiM) applications. Besides electrical properties, it well outperforms other LiM devices due to simple structure and fab-friendly materials, inspiring a new approach to capitalize on the salient features of ferroelectric HZO for LiM applications.

Ultra-violet laser thermal annealing (LTA) is proposed to form contact TiSix for sub-10 nm FinFETs. Compared to conventional rapid thermal annealing (RTA), LTA process leads to reduced total series resistance (RTotal) by 10.1∼16.1% and 13.0∼15.3% which corresponds to enhanced transconductance (gm) by 7.7∼9.8% and 5.9∼9.0% for N-/P-FinFETs respectively due to improved contact resistivity (ρc) by 69% arising from more orderly local Ti-Si bonds and smoother TiSix/Si interface. There is also no concern of LTA process in terms of comparable off-state/junction leakage and reliability by hot carrier stress. In addition, LTA is VLSI-compatible without adding any process complexity. These promising properties enable LTA to further unleash the performance of FinFETs.

To simply and effectively enhance the conversion capability of wearable thermoelectric textiles, a two-step in situ method is adopted to fabricate dual-shell photothermoelectric textiles which is made of polypropylene fibers with a photo-thermal layer (PPy) and a thermoelectric layer (PEDOT:Tos). The PPy is tailored to achieve high temperature and photothermoelectric effects. The PPy layer can significantly increase the photothermal conversion efficiencies of as-prepared fabric. The optimized photothermoelectric fabric can improve the generated voltage output from 294.13 to 536.47 μV under the infrared light, and its power density is up to 13.76 nW·m-2. A flexible photothermoelectric strip composed of as-prepared fabric coated with Ag particles and textile substrates with low thermal conductivity shows a voltage output of 2.25, 0.677, and 0.183 mV and a power output of 0.7031, 0.0636, and 0.0049 nW under IR light, sunlight, and on the arm, respectively. The photothermoelectric fabrics display potential as to a new smart wearable device for converting light and electricity.

The use of regular wound dressings commonly brings about excessively retained wound exudate between the dressing and the wound, which is detrimental to the healing. This study manages to control the biofluid around wounds effectively. To begin with, silk fibroin (SF) is extracted from silk. Next, SF and PCL are mixed and electrospun into multiscale hydrophobic nanofibers on the surface of the dopamine (PDA)-treated hydrophilic PVA nanofibrous membranes, thereby forming asymmetric wetability composite membranes with one-way water conduction. Moreover, PVA nanofibrous membranes are immersed in a PDA solution with an attempt to have a greater surface chemical activity and thus demonstrate an 85% greater wicking height and an air permeability being 90 mm/s. A 20% (w/v) SF solution and an 8% (w/v) PCL solution with a feeding rate being 1:3 provide the resulting SF/PCL nanofibrous membranes with greater hydrophobic properties, namely a water contact angle being 112°. In addition, the ultimate asymmetric wetability composite membranes exhibit an excellent wetting gradient, which benefits the directional transmission of moisture. The moisture management test results indicate that when the electrospinning time for PVA and SF/PCL layers is separately 30 min and 5 min, the resulting composite membranes attain the effect of one-way water conduction. In vitro analysis confirmed that the composite membrane produced were non-toxic. This unique wound dressing with one-way water conduction has a giant potential to serve as new type wound dressings for clinical use.

This study explores the influences of needle punching and a shear-thickening fluid (STF) on the stab resistance sandwich-structured composites made of nylon nonwoven and aramid fabrics. Needle punching and different treatments of aramid fabric are conducted to obtain the composites. The effects of needle punching and different treatments of aramid fabrics on the sandwich-structured composites were examined using quasi-static puncture resistance, quasi-static stab resistance, dynamic puncture resistance, and bursting property tests. Results show that needle punching and incorporation of STF positively influence the stab resistance of the composites. This study provides an innovative method to reduce the number of lamination layers and decrease the weight.

In this study, electrospun polyvinylidene fluoride (PVDF)-based nanofibrous membranes embedding TiO2 were prepared and used for photocatalytic degradation and oil/water separation. The nanofibrous membranes were characterized by scanning electron microscopy (SEM), transmission electronic microscope (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) spectroscopy, thermal performance analysis, and oil/water separation analysis. And the degradation of rhodamine B dye was also investigated. Results showed that the fiber diameter and thermal stability of the membranes decreased with the increasing of TiO2. Meanwhile, the fiber surface roughness and specific surface area increased. The analysis of TEM, XRD and FTIR indicated that TiO2 existed in the PVDF membranes. When the TiO2 content was 12 %, the fiber diameter of the membranes was about 110 nm, and the photocatalytic degradation of rhodamine B dye efficiency was up to 97 %. The reaction rate constant was 0.02057 min−1. At 0.01 MPa vacuum, oil separated from water effectively, which proves that separation can be easily conducted with a low energy cost. Thus, the prepared membranes have a very high application prospect in the purification of reclaimed water and separation of oil and water.

With the significant advances in electronic products, materials with good flexibility, corrosion resistance, high electrical conductivity and minimal thickness are urgently needed. Herein, we demonstrate the biomimetic core–shell structure of lightweight, flexible, self-cleaning nanofiber films for high-performance electromagnetic interference (EMI) shielding by tuning the deposition of Ag nanoparticles (AgNPs). With a thickness of 0.06 mm, PAN@TiO2@AgNPs composite films (PTA films) exhibit an average EMI shielding effectiveness (SE) of 82.60 dB. After further processing with fluorine-containing molecules, the PTA-4 film becomes superhydrophobic and anticorrosive. After a hydrophobic treatment, composite films have average SE, specific SE (SSE) and SSE/t being 79.57 dB, 360.86 dB cm3 g−1, and 60143.33 dB cm2 g−1, respectively. In particular, conductive films that undergo UV radiation and bending cycles retain a stabilized electrical conductivity. This tuning bio-inspired fabrication method provides the films with UV-resistance, superhydrophobicity and EMI SE that fit the practical applications of wearable and flexible sensors.

In order to make conductive woven fabrics with electromagnetic shielding effectiveness (EMSE) and flame retardance, polysufonamide (PSA)/stainless steel (SS) core yarn are used as the weft yarns and PSA yarns are used as the warp yarns. The conductive woven fabrics are denoted as SS-60, SS-80, SS-100, SS-120, and SS-140 according to the twist counts of the core yarn, and evaluated in terms of mechanical properties, flame retardance, surface resistivity. The test results show that the best twist of the core yarn is 120 turns/10 cm. SS-60 has the maximum burnt length, while SS-140 has the minimum burnt length. Moreover, the surface resistivity of the PSA/SS woven fabrics is proportional to the twist counts, and the surface resistivity along the warp direction is higher than that along the weft direction. Changing the fabric lamination angle can form a complete shielding network, and the EMSE is significantly increased. For SS-80, SS-100, and SS-120, when they are composed of 4–6 layers with lamination angles of 0°/45°/90°/-45°/0°/45° and 0°/90°/0°/90°/0°/90°, the EMSE is above 40 dB and the shielding effect is above 99.99 % against the incident waves at 2000–3000 MHz. Specifically, SS-120 has the maximum EMSE of 64 dB against incident waves at 2844 MHz.

Geosynthetic clay liners (GCLs) are commonly used in engineering to prevent seepage. These liners’ surface fabric often suffers damage, especially in toxic environments and under high pressure. To mechanically strengthen the GCLs, this study proposes reinforcement by using needle bonding and glass geogrid to establish glass-geogrid-reinforced GCLs (i.e., GGCLs), consisting of glass geogrid, bentonite layer, and 0.3 mm thick melt-blown nonwoven fabric. Tensile durability of GGCLs was determined by exposing them to thermal oxidation and UV degradation. Hydraulic conductivity and heavy metal ions adsorption of GGCLs was explored to simulate the damage caused by garbage leachate. Tensile strengths of polyamide (PA)- and polyethylene terephthalate (PET)-contained GGCLs retained greater than 73% and 90%, respectively, even after 20 h thermal oxidation at 100°C and 60 h UV degradation. Improvement of hydraulic conductivity after 2 h adsorptions of Cu2+, Ni2+, and Pb2+ reached 51.09, 51.04, and 45.56%. The absorptions of Cu2+ and Ni2+ conformed to the quasi-secondary dynamics model, but that of Pb2+ followed both the quasi-first-order and quasi-secondary dynamics models. The mechanical properties and impermeability of the resulting GGCLs declined under the simulated conditions. This study provides a basic theory to predict the durability and adsorption of heavy metal ion of landfill GGCLs under natural and severe weather conditions.

In this paper, the shear-thickening fluids(STFs) are prepared by 0.5 µm and 12 nm silica particles. The STFs rheological properties and the performance of stab resistance are studied. SiO2 particles with two sizes (12 nm and 0.5 µm) are mixed at different weight ratios to form shear thickening fluids and its rheological behaviors are tested. Next, the quasi-static spike and knife stab resistances, dynamic impact strength, and yarn pull-out of shear thickening fluid-impregnated Kevlar fabrics are tested. The investigation showed that the micro- and nano-sized particles of silica are present in the compound shear thickening fluid, and the rheological behavior was positively improved. Regardless of whether shear thickening fluid is composed of mono-sized or binary particle-sized SiO2 particles, the presence of shear thickening fluids can significantly strengthen Kevlar fabrics in terms of the quasi-static spike and knife stab resistances, dynamic impact strength, and promote the friction force of inter-yarn. In particular, shear thickening fluid-impregnated Kevlar fabrics have better performances when being composed of 12 nm and 0.5 µm SiO2 particles at ratios of 2:1, 1:1, and 1:2 than when being made of only micro-sized or nano-sized particles.

Bio-ceramic hydroxyapatite (HA) coating has been commonly used to repair the bones or as the functionalized surface of bone substitutes due to its excellent biocompatibility, superior osteo-inductivity, and great corrosion resistance. Among many other methods for synthesizing HA coating, coating via the electrochemical deposition has a high degree of crystallinity and purity, which fits the nonlinear, complex, and rugged substrates. Furthermore, HA coating can be adjusted in terms of coating morphology, thickness, and chemical component via changing the parameters, such as electrolyte ion concentration, electrolyte composition, deposition current density, and deposition time, etc. Nevertheless, the properties of electrodeposited HA coating highly pertain to the bubbles generated by water electrolysis on the substrate surface as well as the concentration polarization of electrolyte ions near the cathode during the electrodeposition process. In this study, the critical factors and mechanisms of HA coating using the electrochemical deposition method are comprehensively evaluated, thereby examining the effects of parameter optimization (i.e., current mode, ultrasonic treatment, and postprocessing). Finally, the influences of ion substitution and HA composite coating on the surface structure and properties of the HA-based coatings are also discussed.

Environmental pollution, especially air pollution, seriously endangers public health globally. Due to severe air pollution, air filters still face many challenges, especially in terms of filtration...

In this study, two natural clay minerals were combined with hydrogels to study the influence of natural adsorbents on the adsorption performance of hydrogels. Here, we separately doped bentonite and vermiculite and discussed their mechanical properties and adsorption properties. It was found that the compressive performance of the hydrogel added with clay increased by 21.6% and the swelling performance decreased or increased to varying degrees. Regarding the adsorption performance of hydrogels, it can be seen from the adsorption Langmuir isotherm model that the adsorption capacity of clay-hydrogels is improved to varying degrees (6.6%-15.8%) compared with non-clay-hydrogels, and clay-hydrogels have different degrees of improvement (6.6%-15.8%). The hydrogel has a removal efficiency of more than 95% for low concentrations of heavy-metal ions and dyes. In addition, the clay-hydrogel has low cost and is easy to prepare, and can be recycled many times. Therefore, the material is of great significance for the treatment of pollutants. PRACTITIONER POINTS: The effect of natural clay on the adsorption performance of hydrogels was studied. Clay can enhance the compression and adsorption properties of hydrogels. The adsorption mechanism and adsorption capacity of clay hydrogels were evaluated.

Drug delivery technology can prevent wound infection and inflammatory reactions and accelerate wound healing and quality. In this paper, we propose preparing a multifunctional medical dressing to meet the various needs of people for dressing. A multi-layered composite nanofiber membrane was constructed using silk fibroin as the substrate, and mesoporous silica nanoparticles (MSN) with high adsorption properties were first prepared and then electrosprayed on silk fibroin (SF)/chitosan (CS) microspheres to form MSN-SF/CS microspheres with uniform distribution. Then the MSN-SF/CS microspheres were sprayed on the silk fibroin (SF)/polycaprolactone (PCL)-polyvinyl alcohol (PVA) unidirectional water-conducting composite nanofiber membrane. The test results showed that the encapsulation rate of bovine serum albumin (BSA) by MSN-SF/CS drug-loaded microspheres was 65.53% and the cumulative release rate in vitro was 54.46%. The results of in vitro experiments also showed its good antibacterial effect and good biocompatibility. To eliminate excess wound exudate and reduce inflammation, the cumulative unidirectional transport capacity (AOTC) of 651.75% was achieved by spraying the microspheres on an SF/PCL- PVA unidirectional water conductive composite membrane. This study could stimulate and promote the use of additional wound healing biomaterials in clinical medicine.

Glass geotextile reinforcement and needle-punch bonding are applied to compensate for the low mechanical strength of a geotextile clay liner (GCL) and reduce damage under complicated service condit...