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Stress-induced corrosion impairs the mechanical integrity of magnesium (Mg) and its alloys as potential orthopedic implants. Although there has been extensive work reporting the effects of stress on Mg corrosion in vitro, the geometric design principles of the Mg-based orthopedic devices still remain largely unknown. In this work, a numerical simulation model mimicking fractured bone fixation and surgical animal models were applied to investigate the effects of the geometric design of Mg screws on the stress distribution and the stress-induced degradation behavior. Finite element (FE) analysis was used for calculation of stress concentrations around the Mg screws, with different thread type, thread pitch, and thread width. Afterward, the Mg screws of the pre-optimization and post-optimization groups exhibiting the highest and lowest stress concentrations, respectively, were implanted in the fractured distal femora and back subcutaneous tissue of rabbits. Encouragingly, there was a significant difference between the pre-optimization and the post-optimization groups in the degradation rate of the stressed screw parts located around the fracture line. Interestingly, there was no significant difference between the two groups in the degradation rate of the non-stressed screw parts. Consistently, the Mg screw post-optimization exhibited a significantly lower degradation rate than that pre-optimization in the back subcutaneous implantation model, which generated stress in the whole screw body. The alteration in geometric design did not affect the corrosion rate of the Mg screws in an immersion test without load applied. Importantly, an accelerated new bone formation with less fibrous encapsulation around the screws was observed in the Mg group post-optimization relative to the Mg group pre-optimization and the poly (lactic acid) group. Geometry optimization may be a promising strategy to reduce stress-induced corrosion in Mg-based orthopedic devices. Stress concentrations influence corrosion characteristics of magnesium (Mg)-based implants. The geometric design parameters, including thread type, thread pitch, and thread width of the Mg screws, were optimized through finite element analysis to reduce stress concentrations in a fractured model. The Mg screws with triangular thread type, 2.25 mm pitch, and 0.3 mm thread width, exhibiting the lowest maximum von Mises stress, showed a significant decrease in the volume loss relative to the Mg screws pre-optimization. Compared with the Mg screw pre-optimization and the poly(lactic acid) screw, the Mg screw post-optimization favored new bone formation while inhibiting fibrous encapsulation. Collectively, optimization in the geometric design is a promising approach to reduce stress-induced corrosion in Mg-based implants. [Display omitted] [ABSTRACT FROM AUTHOR]

Cimifugin (CIM) is a chromone component of Saposhnikoviae Radix, which has good anti-inflammatory activity. In this study, 21 CIM amino acid ester derivatives were synthesized. CIM and its derivatives CIM 2, CIM 3, CIM 7, and CIM 11 have good inhibitory effects on the release of nitric oxide in lipopolysaccharide-induced mouse macrophages (RAW 264.7) inflammation model. The inhibitory effect of CIM 3 was 3 times that of CIM. The IC 50 of NO inhibition rate were 0.61 ± 0.06, 1.53 ± 0.11 μmol/L. CIM 3 also had the best inhibitory effect on the release of IL-1β, TNF-α and IL-6 in cell supernatant. CIM 3 significantly alleviated mouse ear swelling, prolonged mouse heat pain threshold, and reduced the number of writhing induced by acetic acid in vivo. These results indicate that the anti-inflammatory and analgesic activity of CIM 3 is significantly better than that of the original drug CIM. [Display omitted] • The synthesis method of cimifugin amino acid ester derivatives was established. • The 21 cimifugin amino acid ester derivatives isolated and identified were all new compounds. • Compared with cimifugin, derivative 3 has better anti-inflammatory activity in vitro and in vivo. • Compared with cimifugin, derivative 3 has better analgesic activity in vivo. [ABSTRACT FROM AUTHOR]

Metallopolymers have emerged as a new type of advanced materials for multiple applications, involving nanoscience, energy storage and conversion, catalysis, as well as biomedicine. Metal components play a significant role in the performances and functionalities of metallopolymers, and can endow metallopolymers with unique optical, magnetic, electronic, catalytic and redox characteristics. In addition, the polymer backbones also provide good mechanical, processing and soluble properties to broaden the practicability of metallopolymers. Metal centers can be incorporated into polymer main chain, side chain or network to produce various metallopolymers. The current research interests are to design and develop functional metallopolymers with specific structures and required properties for valuable applications. This review focuses on recent advances of metallopolymers for multiple applications, such as self-assembly, biomaterials, optoelectronic materials, catalysis, smart gels and microgels, and ion-exchange membranes. This review is expected to give some insight into metallopolymers for developing the desired functional materials. [Display omitted] [ABSTRACT FROM AUTHOR]

With the growing demand for eco-friendly materials in wearable smart electronic devices, renewable, biocompatible, and low-cost hydrogels based on natural polymers have attracted much attention. Cellulose, as one of the renewable and degradable natural polymers, shows great potential in wearable smart electronic devices. Multifunctional conductive cellulose-based hydrogels are designed for flexible electronic devices by adding sodium carboxymethyl cellulose and MXene into polyacrylic acid networks. The multifunctional hydrogels possess excellent mechanical property (stress: 310 kPa; strain: 1127 %), toughness (206.67 KJ m−3), conductivity (1.09 ± 0.12 S m−1) and adhesion (82.19 ± 3.65 kPa). The multifunctional conductive hydrogels serve as strain sensors (Gauge Factor (GF) = 5.79, 0–700 % strain; GF = 14.0, 700–900 % strain; GF = 40.36, 900–1000 % strain; response time: 300 ms; recovery time: 200 ms) and temperature sensors (Temperature coefficient of resistance (TCR) = 2.5755 °C−1 at 35 °C- 60 °C). The sensor detects human activities with clear and steady signals. A distributed array of flexible sensors is created to measure the magnitude and distribution of pressure and a hydrogel-based flexible touch keyboard is also fabricated to recognize writing trajectories, pressures and speeds. Furthermore, a flexible hydrogel-based supercapacitor powers the LED and exhibits good cyclic stability over 15,000 charge-discharge cycles. [Display omitted] [ABSTRACT FROM AUTHOR]

Dendronized polymers (DPs) are an increasing field at the interfaces between organic chemistry, polymer synthesis, and materials science, and in particular DPs are expected to provide designed applications as nanoparticle (NP) sensors and catalysts. Herein, we report a new highly-branched amphiphilic dendronized diblock copolymer containing bulky hydrophilic triethylene glycol (TEG) and hydrophobic ferrocenyl (Fc) groups via the living and controlled ring-opening metathesis polymerization. The amphiphilicity drives the self-assembly of the resulting DP into spherical nanoscale micelles in water using THF or DMSO as cosolvents. AuNPs and AgNPs of various sizes depending on the presence of NaBH 4 are successfully prepared using the DP as stabilizers or reductants and used as excellent catalysts for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol by NaBH 4. The obtained AuNPs about 2.1 nm show TONs up to 25 000 and TOFs of 26 400 h−1 and remain stable and efficient for this catalysis after two months. Highly-branched amphiphilic ferrocenyl-containing dendronized diblock copolymer is prepared by ROMP and used as stabilizers or reductants to synthesize AuNPs and AgNPs for high-efficiency catalysis in 4-nitrophenol reduction. Image 1 • Ferrocenyl dendronized diblock copolymer is synthesized by ROMP. • Dendronized copolymer can self-assemble into nanoscale spherical micelles. • Dendronized copolymer can be used as reducing and stabilizing agents for AuNPs/AgNPs. • AuNPs and AgNPs show high catalytic activity for 4-nitrophenol reduction. • AuNPs and AgNPs show long-term stability and efficiency for catalysis. [ABSTRACT FROM AUTHOR]

Polymer self-assembly has attracted considerable attention for constructing interesting nanostructures. Dendronized polymers with a linear polymer backbone and dendritic wedges possess the potential to self-assemble into ordered nanostructures in solution. Herein, the self-assembly behaviors of dendronized ferrocenyl polymers are investigated in aqueous solution. After being oxidized with FeCl 3 ·6H 2 O, dendronized ferrocenyl polymers form positively charged ferrocenium-containing polyelectrolytes to generate nano-objects in aqueous solution. In addition, the supramolecular polymers obtained from the host–guest interactions between ferrocenyl units and β-cyclodextrin are also able to form nano-objects in aqueous solution. Whereafter, both the oxidized and supramolecular polymers are used to encapsulate Rhodamine B, resulting in the cargo-loaded self-assembly. All self-assembly experiments demonstrate that the dendritic effects would drive ferrocenyl polymers to self-assemble from small micelles to large compound micelles. The ferrocenyl polymers with larger dendritic pendant sizes have a more obvious tendency to self-assemble into large compound micelles. The current work gives a chance to understand the self-assembly behaviors of dendronized polymers, which is expected to generate ordered nanostructures. [Display omitted] • Self-assembly behaviors of dendronized ferrocenyl polymers. • Self-assembly of dendronized ferrocenyl polymers based on oxidation. • Self-assembly of dendronized ferrocenyl polymers based on host−guest interaction. • Cargo-loaded self-assembly of dendronized ferrocenyl polymers. • Role of dendritic pendant sizes in the self-assembly behaviors. [ABSTRACT FROM AUTHOR]

Gallol-functionalized polymers are highly desirable for their addressable functions in the fields of materials science, nanotechnology and biomedicine, owing to gallol's unique chemistry including excellent chelating properties to metals, easily oxidability and superior ability to bind proteins. Herein, we report the controlled synthesis of the first polynorbornene-based side-chain gallol-containing homopolymers and block copolymers with pendent triethylene glycol (TEG) moieties by the ring-opening metathesis polymerization (ROMP) using the 3rd generation Grubbs catalyst 1 as the initiator. We describe the direct synthetic route by the ROMP of a gallol-containing norbornene monomer, and the indirect approach via an acetoxyl protection/deprotection route. Among the tested metal ions of Fe 3+ , Mg 2+ , Cr 3+ and Al 3+ , Fe 3+ is the most effective metal ion to induce the gelation of the present gallol-containing polymers, and UV–visible spectroscopy indicates that bis-coordinated state dominates for the interaction between side-chain gallol groups and Fe 3+ ions in DMF. The gelation rate, interior structure, thermal and mechanical properties of the Fe 3+ -induced metallogels can be effectively tuned by changing the gallol/Fe 3+ molar ratio, polymeric molecular weight, and by introducing of organic TEG block. Furthermore, the oxidant-induced organogels were fabricated by adding the oxidant of NaIO 4 into the DMF solution of the gallol-containing polymers, and the gelation rate highly depends on the gallol/IO 4 − molar ratio and the introduction of TEG block. We are convinced that the effective synthesis of well-defined gallol-containing polymers, as illustrated by the present work, will pave the way for their functional applications as smart organogels, coatings, adhesives, capsules, etc. [ABSTRACT FROM AUTHOR]

Biopolymer-derived hydrogels with low-cost and sustainable features have been considered as fascinating supported materials for metal nanoparticles. Cellulose, as the most abundant biopolymer, is a renewable raw material to prepare biopolymer-derived hydrogels for catalysis. Here, a cellulose-based hydrogel is designed to load bimetallic (AuAg, AuPd and AgPd) nanoparticles. 4-Nitrophenol reduction and Suzuki–Miyaura coupling reactions are selected to evaluate and compare the catalytic performance of the resulting bimetallic nanoparticle-loaded cellulose-based composite hydrogels. The bimetallic nanocomposite hydrogels are easy to be recycled over 10 times during the catalytic experiments and possess good applicability and generality for various substrates. The catalytic activity of bimetallic nanocomposite hydrogels was compared with recent literatures. In addition, the possible catalytic mechanism is also proposed. This work is expected to give a new insight for designing and preparing bimetallic nanoparticle-based cellulose hydrogels and proves its applicability and prospect in the catalytic field. [Display omitted] [ABSTRACT FROM AUTHOR]

Polysaccharides are a kind of natural biopolymers and have been widely applied in various fields, especially biomedical applications, due to their fascinating properties, such as renewability, structural diversity, biodegradability and biocompatibility. However, pristine polysaccharides sometimes fail to meet the requirements in biomedical applications. Chemical modifications offer a significant means of changing the physical and chemical properties of polysaccharides and enhancing their functionalities. The traditional modification methods mainly include selective oxidation, carboxymethylation, acetylation, phosphorylation, sulfation, "Click" reactions and polymer grafts. In recent years, mussel-inspired chemistry has emerged as a novel, simple and efficient strategy to modify natural polysaccharides, therefore endowing them with some new and unique properties and broaden their applications in biomedicine. This strategy can give polysaccharides with outstanding adhesive performance, oxidation resistance, antibacterial property, coating capacity, high reactivity, chelating and coordinating abilities, bioactivities, and biological compatibility, and also affords a significant surface modification platform for the fabrication of diverse hybrid materials with specific functionalities. This review summarizes the methods (including surface chemistry and covalent conjugate) to modify various natural polysaccharides (including cellulose, chitin, chitosan, alginate, hyaluronic acid, heparin, starch, etc.) via mussel-inspired chemistry, and discusses their various biomedical applications such as tissue engineering, hemostasis, wound healing, drug delivery, antibacterial, chemo-photothermal therapy, biosensors and 3D bioprinting. This work is expected to give a better understanding of opportunities and challenges of mussel-inspired strategy for the functionalization of polysaccharides in biomedical applications. It can envision that mussel-inspired strategy will continuously attract attention in the modification of polysaccharides and more significant applications will be explored. [Display omitted] [ABSTRACT FROM AUTHOR]

Metal nanoparticle composite hydrogels (MNCHs) have attracted considerable attention in the catalytic field because hydrogels can provide appropriate microenvironment and enable catalysts to be conveniently separated and recycled. Here, a novel and well-defined gallol-functionalized hydrogel Gel-G was synthesized by ring-opening metathesis polymerization (ROMP). The resulting hydrogel Gel-G can be used as template to in situ prepare catalytically active gold nanoparticles hydrogel (AuNPs-Gel-G) and sliver nanoparticles hydrogel (AgNPs-Gel-G) without use of any external reductant based on the strong reducibility and coating property of the gallol moiety. The two MNCHs were well characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). Both AuNPs-Gel-G and AgNPs-Gel-G exhibited high catalytic activity for the 4-nitrophenol (4-NP) reduction to 4-aminophenol (4-AP), and can be easily separated and reused at least five times. [Display omitted] • Gallol-containing polymer hydrogels are synthesized by ROMP. • Gallol-containing polymer hydrogels are used for in situ fabrication of AuNPs and AgNPs composites. • AuNPs and AgNPs hydrogel composites exhibit good catalytic activity and reusability for 4-nitrophenol reduction. [ABSTRACT FROM AUTHOR]

ZnO NRs-based self-powered ultraviolet (UV) photodetectors (PDs) have gained significant interest from researcher recently, owing to its high stability and optoelectronic performance. However, the slow responding speed and high dark current caused by defects in ZnO NRs limit the application of self-powered UV PDs. Organic conducting polymer poly(3,4-ethylenedioxyselenophene) (PEDOS) has been used as p-type materials, because its good hole transport ability can enable excellent photodetection performances. Here, a self-powered PEDOS/Au NPs-ZnO hybrid UV PD is reported, having a high responsivity of 0.369 mA/W, a favorable detectivity of 1.17 × 1010 Jones as well as fast photo response time (τ rise and τ fall of 0.32 s and 0.44 s) in self-powered mode. In addition, the I ph / I dark ratio of this PD is about 39, and has almost no change after 8 cycles. Comparing with the UV PD without Au NPs (ZnO NRs/PEDOS), the dark current of PEDOS/Au NPs-ZnO UV PD is reduced by 2 times (from 1.52 μA to 0.75 μA) and its photocurrent is increased by 8 times (from 3.79 μA to 29.1 μA). The result shows that p-type PEDOS form p-n heterostructure with ZnO NRs, and the plasmonic effect of Au NPs can enhance response characteristics of the UV PDs. [Display omitted] • A high performance self-powered UV PD was designed based on Au NPs decorated n-type ZnO NRs and p-type PEDOS p-n heterojunction. • The plasma effect of Au NPs on the UV detection performance of PEDOS/Au NPs-ZnO heterojunctions was studied. • The hybrid device exhibits excellent responsivity and detectivity under lower light power (0.32 mW/cm2). • This study presented a new idea to efficiently enhance the properties of the organic-inorganic p-n heterojunction UV PDs. [ABSTRACT FROM AUTHOR]

Hydrogels with stimuli-responsive behavior have been of great interest to researchers from many fields, such as biotechnology, drug delivery, and sensors, owing to their "smart" change in properties under external stimuli such as temperature, pH, pressure, redox, magnetic and electric fields. In this work, using the third generation Grubbs' catalyst as the initiator, both temperature and β-cyclodextrin (β-CD) stimuli-responsive ferrocenyl hydrogels were prepared with different proportions of hydrophilic norbornene monomer NTEG , ferrocene-containing monomer NFc and crosslinker 1 by using one-pot ROMP (ring-opening metathesis polymerization) reaction. Based on the mechanical and rheological tests, it was found that NFc not only played a crucial role in maintaining the structure of ferrocenyl hydrogels, but also enhanced their physical strength. Comparatively, the increase of the NTEG content in the hydrogel system can improve the toughness of the resulting hydrogels. Furthermore, Results of the swelling ratio test demonstrated that these hydrogels possessed temperature-responsiveness, in which the NTEG block, which contained dendritic oligoethylene glycol structures in the side chain, played a decisive role. Simultaneously, it is worth noting that these ferrocenyl hydrogels also exhibited responsive behavior to β-CD solution due to the host-guest interaction of ferrocene unit with β-CD macromolecule. Therefore, we believe that this study provides a new idea for the design of covalently crosslinked ferrocenyl stimuli-responsive smart hydrogels. Thermo/β-cyclodextrin-responsive ferrocenyl hydrogels were constructed by the ROMP reaction of a hydrophilic norbornene monomer containing dendritic oligoethylene glycol structures in the side chain and a hydrophobic side-chain ferrocene-containing monomer, and their mechanical and swelling properties could regulated by the hydrophilic-hydrophobic ratio, environmental temperature and the addition of β-cyclodextrin. [Display omitted] • Hydrogels with pendent ferrocene and dendritic oligoethylene glycol were prepared. • Ferrocenyl hydrogels were covalently cross-linked through the ROMP reaction. • Ferrocenyl hydrogels had excellent toughness and compression resilience. • Mechanical/swelling behavior of hydrogels can be regulated by changing feed ratio. • Ferrocenyl hydrogels possessed dual-responsiveness to temperature and β-CD. [ABSTRACT FROM AUTHOR]

In this study, a novel organic-inorganic self-powered UV photodetector (UV PD) is realized by the face-to-face assembling of poly(3,4-ethylenedioxyselenophene) (PEDOS)/FTO and ZnO nanoarrays (ZnO NRs)/FTO. The ZnO NRs are further modified with carbon quantum dots (CQDs) to achieve high-performance capability of UV PD. As a hole transport material, PEDOS can enhance the charge transfer ability and form p-n heterojunction with ZnO NRs, which can separate the electron-hole pairs under the effect of the built-in electric field, making the UV PD achieve better photoelectric performance without external bias. In addition, a pyroelectric effect is found between ZnO NRs and CQDs and can greatly improve the photoresponsivity and shorten the response time of UV PD. The UV PD from CQDs-ZnO NRs/PEDOS has the excellent performance with photoresponsivity of 22.62 mA W−1 and response speed of 0.09 s/0.12 s (rise time/decay time) under the low ultraviolet light intensity (0.32 mW cm−2, wavelength 365 nm) at 0 V bias. This work provides an effective route to modulate the performance of UV PDs. [Display omitted] • The performance of ZnO based UV photodetector modified by carbon quantum dots is 33 times higher. • Assembled face-to-face organic-inorganic heterojunction ultraviolet photodetector FTO/CQDs-ZnO NRs/PEDOS/FTO. • The pyroelectric effect of carbon quantum dots greatly improves the device response and shortens the response time. • The mechanism of improving device performance by carbon quantum dots is discussed in detail. [ABSTRACT FROM AUTHOR]

Acetaminophen (APAP, also known as paracetamol) is a commonly used antipyretic and analgesic that is considered safe to use during pregnancy. However, a growing body of research indicates that gestational administration of APAP increased the risk of neurodevelopmental, reproductive and genitourinary disorders in offspring, alongside impairments in placental development. Notably, over-dosed APAP exhibits direct toxicity to endothelial cells, but there is very limited research investigating the impact of APAP on placental angiogenesis, a gap we aim to address in this study. Pregnant mice were gavaged with APAP (15, 50 and 150 mg/kg/d) from embryonic day 11.5 (E11.5) to E13.5. Administration of 150 mg/kg/d APAP leads to low birth weight (LBW) of the offspring and disordered vascular structures within the labyrinthine (Lab) layer of the placenta. This disruption is accompanied by a significant increase in Suppressor of Cytokine Signaling 3 (SOCS3) level, a negative regulator of the Janus kinase signal transducer 1 and activator of the transcription 3 (JAK1/STAT3) signaling. Meanwhile, Human umbilical vein endothelial Cells (HUVECs) with the treatment of 3 mM APAP exhibited reduced cell viability, whereas 1 mM APAP significantly affected the proliferation, migration, invasion and angiogenic capacities of HUVECs. Further, SOCS3 was up-regulated in HUVECs, accompanied by inhibition of JAK1/STAT3 pathways. Knocking-down SOCS3 in HUVECs restored the nuclear translocation of STAT3 and efficiently promoted cellular capacity of tube formation. Overall, short-term maternal administration of overdosed APAP impairs angiogenic capacities of fetal endothelial cells via SOCS3/JAK1/STAT3 pathway in the mouse placenta. This study reveals that overdose of APAP during pregnancy may adversely affect placental angiogenesis, emphasizing the importance of adhering to the safe principles of smallest effective dose for the shortest required durations. [Display omitted] • Exposure to acetaminophen (APAP) disrupted placental development in mice. • APAP exposure caused abnormal vascular structures in the placenta. • APAP exposure impaired angiogenesis via SOCS3/JAK1/STAT3 pathway. [ABSTRACT FROM AUTHOR]

[Display omitted] • A high performance self-powered UV PD was designed based on a sandwich configuration and with p-n junction, which is consisting of ZnO as the bottom n- layer, PEDOS as the top of p-layer, and ZnSe as the insertion layer. • The study suggestion that the ZnSe layer acts a key role in the superior property of the obtained device. • A high detectivity (1.42 × 1011) and a responsivity (5.44 mA/W) values were achieved under low light power (0.32 mW/cm2). • This study presented a new idea to efficiently enhance the properties of the organic–inorganic p-n heterojunction UV PDs. In the present work, a novel self-powered hybrid ultraviolet (UV) photodetector (PD) based on ZnO @ZnSe nanoarrays/poly(3,4-ethylenedioxyselenophene) (PEDOS) was fabricated and systematically investigated. The designed PD is based on a sandwich configuration and with p-n junction, which is consisting of ZnO as the bottom n- layer, PEDOS as the top of p-layer, and ZnSe as the insertion layer. The results of the study on the performances of UV PD under different conditions optical power density shows that the ZnO@ZnSe/PEDOS exhibits excellent detection of UV light, the device achieves the excellent responsivity (R) 5.44 mA/W and high detectivity (D*) 1.42 × 1011 Jones under the weaker optical power density (0.32 mW/cm2). The study concludes with a suggestion that the ZnSe layer acts a key role in the superior property of the obtained device, which is introduction of ZnSe layer between the p-PEDOS and n-ZnO layers reduces band migration and thus effectively enhances carrier transport within them, and demonstrating that the responsivity (R) of ZnO@ZnSe/PEDOS is almost 18 times that of the device without the ZnSe layer (0.3 mA/W). On the other hand, as the p- types PEDOS, which enhances the junction quality by reducing the composite center of the carrier, expanding the depletion region and providing a step energy level between the band edges of ZnO and ZnSe, improving the overall collection of photogenerated carriers. [ABSTRACT FROM AUTHOR]

L-Tryptophan (L-Trp) is essential for the human body and can only be obtained externally. It is important to develop a method to efficiently detect L-Trp in food. In this work, ionic liquid (IL) modified poly(3,4-ethylendioxythiophene)/ Titanium carbide (PEDOT/Ti 3 C 2 T X) was used as a substrate material to improve detection sensitivity. Molecular imprinted polymers (MIP) film for specific recognition of L-Trp was fabricated on the surface of modified electrodes using electrochemical polymerization. The monitoring results showed that the molecularly imprinted electrochemical sensors (MIECS) exhibited good linearity ranges (10−6 - 0.1 μM and 0.1–100 μM) with a low detection limit (LOD) of 2.09 × 10−7 μM. In addition, the MIECS exhibited remarkable stability, reproducibility, and immunity to interference. A good recovery (93.54–99.59%) was demonstrated in the detection of milk. The sensor was expected to be developed as a highly selective and sensitive portable assay, and applied to the detection of L-Trp in food. • Construction of a 3D conductive framework of PEDOT/Ti 3 C 2 T x /IL as a substrate material to improve the sensitivity of the sensor. • The sensor has good immunity and selectivity for various amino acids and biomolecules. • The sensor enables stable detection of L-Trp for 15 consecutive times. • The sensor has a detection limit of 2.09 × 10−7 μM in the range of 10−6-0.1 and 0.1-100 μM, enabling pic-omolar detection of L-Trp. [ABSTRACT FROM AUTHOR]

Abstract: We build a model to study the sidewall corrugation of fabricated silicon microrings and investigate its impact on the spectral response of the resonator system. From the scanning electron microscope images, the sidewall corrugation can be engineered into certain periodicity and characterized into a group of rectangular gratings, or quasi-gratings, which in turn generate mutual mode coupling between the forward- and backward-propagating modes in the ring and lead to resonance splitting. We find that the reflectivity of the quasi-gratings is proportional to the mutual coupling strength and the resonance splitting only occurs at the resonances where high reflectivity takes place. The model agrees well with the experimental measurements and provides some guideline in applying mutual mode coupling for various functions in the field of optics. [Copyright &y& Elsevier]

Although polymers based on polylactic acid (PLA) are considered by researchers as prime candidates for replacing traditional plastics, they are confronted with challenges including high production costs, limited thermal stability, and inferior impact resistance. In this study, novel composites with exceptional impact resistance, robust thermal stability, and satisfactory crystalline properties were fabricated by using PLA and polypropylene (PP) as raw materials, PP- g -MAH was employed as a compatibilizer to enhance the compatibility between the individual components. by adjusting the quantity of discarded cotton stalk fibers (CSF). The optimal mass ratio of CSF was determined to be 20%, resulting in a composite that exhibited a moderate increase of 56.31% in impact strength and a remarkable improvement of 23.05% in Vicat softening temperature. While the crystallinity was enhanced and the crystallization temperature (T c) value decreased, the storage modulus also increased. Furthermore, the observed increase in storage modulus within the temperature range of 80 °C–100 °C was attributed to the influence of polymer cold crystallization. The hydrophobicity of the composite was enhanced. Significantly, this strategy can be extended to the application of other plant fibers, improving the crystalline properties of semi-crystalline polymers such as PLA and exemplifying the true 'valorization of waste' through the secondary utilization of discarded CSF. [Display omitted] • Utilizing discarded cotton stalk fibers, a PLA-based composite was fabricated. • Composite have high impact resistance, thermal stability, and crystalline performance. • The utilization of discarded CSF enhances various properties of PLA-based composites. • It presents a novel strategy for cost-effective applications of PLA-based plastics. [ABSTRACT FROM AUTHOR]

Supercapacitors play a crucial role in energy storage applications due to their high energy and power densities. In this context, synthesizing composites such as: poly(3,4propylenedioxythiophene)/CoNi 2 S 4 @hollow carbon sphere (PProDOT/CoNi 2 S 4 @HCS) through solid-state thermal polymerization and hydrothermal ion exchange has gained significant attention. The PProDOT/CoNi 2 S 4 @HCS composite exhibits exceptional electrochemical performance, including a high specific capacitance of 1054 C g−1 and an initial capacity retention rate of 83.3% at 20 A g−1. This signifies that the composite can effectively store and deliver electrical energy. The composite possesses a three-dimensional core-shell structure, wherein HCS acts as a carbon-based substrate that prevents the aggregation of CoNi 2 S 4 nanoparticles. Simultaneously, the PProDOT film ensures the structural integrity of CoNi 2 S 4 and facilitates efficient electron/ion transfer within the composite. Furthermore, researchers have assembled a quasi-solid-state supercapacitor using the PProDOT/CoNi 2 S 4 @HCS composite and a gel electrolyte composed of polyvinyl alcohol/sulfonated cellulose/gelatin (PVA/sCMC/GEL/KOH). This supercapacitor demonstrates outstanding characteristics, such as a high energy density of 85.3 Wh kg−1, a high power density of 7957 W kg−1, and a capacity retention rate of 87.56% after 15,000 cycles at 4 A g−1. These results indicate that the composite-based supercapacitor can provide long-term stability and reliable performance under demanding operating conditions. [Display omitted] • A ternary core-shell material with ultra-high capacity retention at high current density has been realized. • The conductive polymer coating was prepared by in-situ solid-state thermal polymerization. • Designed a gel electrolyte with high ionic conductivity. [ABSTRACT FROM AUTHOR]

The corrosion behaviour of WE43 alloy in artificial saliva containing different fluoride ion concentrations were investigated in association with microstructural evolution. The WE43 alloy with an average grain size of 10–30 µm was mainly composed of α-Mg matrix and some RE-containing precipitates. The results of electrochemical corrosion and immersion corrosion tests indicated that the corrosion behaviour of WE43 alloy was continuously deteriorated with increasing F- concentration. This deterioration was attributed to the undesirable alterations in thickness, surface morphology and phase constitution of the corrosion products layer with the presence of F-, which damaged its corrosion protection effect in some degree. • Effect of F- on corrosion behaviour of WE43 alloy in artificial saliva was studied. • The WE43 alloy was mainly composed of α-Mg matrix and RE-containing precipitates. • The corrosion behaviour of WE43 alloy was worsened with increasing F- concentration. • Two possible corrosion mechanisms of WE43 alloy with and without F- were proposed. [ABSTRACT FROM AUTHOR]

Abstract The environmental implications of graphene oxide (GO) have received much attention. Transport of GO in subsurface environment is a critical process affecting the migration and potential risks of this important class of carbonaceous nanomaterials. To date, the effects of heterogeneity in porous media, in particular, iron oxides, on GO transport are not well studied. In this study, we investigated the transport properties of GO in saturate quartz sand as affected by the presence of iron oxides, using goethite, hematite and ferrihydrite as the model iron oxide species, and applied a two-site transport model (which accounts for both attachment and straining) to fit the transport data. We found that iron oxide coating on sand surfaces markedly inhibited GO transport, mainly due to increased electrostatic attraction between particles and collectors, as the positively charged iron oxides provided favorable deposition sites for the negatively charged GO nanosheets. Additionally, increased surface roughness was likely an additional mechanism leading to the enhanced GO deposition. The extent of transport inhibition by iron oxides also depended on the morphology iron oxides, in that at the same Fe loading a larger effect was observed when iron oxides existed as the coating on sand surface than as discreet particles. The presence of iron oxide coatings (tested using goethite) could magnify the effects of cations on GO transport. Specifically, the presence of goethite facilitated the accumulation of cations on the surface of sand, and in the case of Ca2+, the binding of GO via the cation-bridging mechanism was enhanced, as goethite contained abundant surface hydroxyl groups that are strong metal-complexing moieties. Graphic abstract Unlabelled Image Highlights • Iron oxides heterogeneity in saturated porous media markedly inhibits GO transport. • Extent of transport inhibition depends on morphology of iron oxides in porous media. • Presence of iron oxide coatings magnifies inhibition effects of cations on transport. • Iron oxides provide additional surface hydroxyl groups that attract cations. [ABSTRACT FROM AUTHOR]

Highlights: [•] The microstructure and composition of HTO was studied. [•] The chemical and microstructure of MAO coating was changed by pre-treatment. [•] Effects of HTO pre-film on corrosion behavior of MAO coating was studied. [Copyright &y& Elsevier]

Abstract: A new electrochemical procedure for the electrocatalytic carboxylation of aromatic ketones with carbon dioxide in ionic liquid, 1-butyl-3-methylimidazolium tetrafluoborate (BMIMBF4), to α-hydroxycarboxylic acid methyl ester was investigated for the first time. The electrochemical behavior of acetophenone in BMIMBF4 was studied by cyclic voltammetry with a reduction peak at −1.9V (vs. Ag). The electrolyses experiments were carried out in an undivided cell under mild conditions without any toxic solvents, catalysts and supporting electrolytes, followed by addition of an alkylating agent, affording the α-hydroxycarboxylic acid methyl ester in a moderate yield (62%). The results showed that the yields were strongly affected by various factors: temperature, current density, charge passed, electrode material and substrate concentration. Moreover, the ionic liquid was successfully recycled for this reaction. [Copyright &y& Elsevier]

Abstract: Objectives: The object of this study is to establish serum protein fingerprint models for early diagnosis and evaluation of luminal stenosis severity of CAD. Design and methods: A total of 189 samples were analyzed by surface-enhanced laser desorption/ionization time of flight mass spectrometry (SELDI-TOF MS) coupled with CM10 chips and bioinformatics tools. Results: Ten top-ranked proteins were selected as the potential fingerprints of pattern 1, which distinguishes patients with significant CAD (stenosis≥50%) from control individuals. Blind test was analyzed on the second day with a specificity of 79.3% and sensitivity of 78.3%. Pattern 2 distinguishes significant CAD from minimal CAD with luminal stenosis between 25% and 50%. The specificity and sensitivity of blind test for pattern 2 are 77.3% and 73.9%, respectively. Conclusions: The SELDI-TOF MS technique combined with bioinformatics approaches may be a novel noninvasive method which can not only facilitate the discovery of diagnostic models for CAD and its severity, but also provide a useful tool for molecular diagnosis. [Copyright &y& Elsevier]