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Semiconducting carbon nanotubes (s-CNTs) have emerged as a promising alternative to traditional silicon for ultrascaled field-effect transistors (FETs), owing to their exceptional properties. Aligned s-CNTs (A-CNTs) are particularly favored for practical applications due to their ability to provide higher driving current and lower contact resistance compared with individual s-CNTs or random networks. Achieving high-semiconducting-purity A-CNTs typically involves conjugated polymer wrapping for selective separation of s-CNTs, followed by self-assembly techniques. However, the presence of the polymer wrapper on A-CNTs can adversely impact electrical contact, gating efficiency, carrier transport, and device-to-device variations, necessitating its complete removal. While various methods have been explored for polymer removal, accurately characterizing the extent of removal remains a challenge. Traditional techniques such as absorption spectroscopy and X-ray photoelectron spectroscopy (XPS) may not accurately depict the remaining polymer content on A-CNTs due to their inherent detection limits. Consequently, the performance of FETs based on pure polymer-wrapper-free A-CNTs is unclear. In this study, we present an approach for preparing high-semiconducting-purity and polymer-wrapper-free A-CNTs using poly[(9,9-dioctylfluorenyl-2,7-dinitrilomethine)-(9,9-dioctylfluorenyl-2,7-dimethine)] (PFO-N-PFO), a degradable polymer, in conjunction with a modified dimension-limited self-alignment process (m-DLSA). Comprehensive transmission electron microscopy (TEM) characterizations, complemented by absorption and XPS characterizations, provide robust evidence of the successful near-complete removal of the polymer wrapper via a cleaning procedure involving acidic degradation, hot solvent rinsing, and vacuum annealing. Furthermore, top-gated FETs based on these high-semiconducting-purity and polymer-wrapper-free A-CNTs exhibit good performance metrics, including an on-current (Ion) of 2.2 mA/μm, peak transconductance (gm) of 1.1 mS/μm, low contact resistance (Rc) of 191 Ω·μm, and negligible hysteresis, representing a significant advancement in the CNT-based FET technology.

With the increasing penetration of renewable generation, producing renewable hydrogen by water electrolysis has become a promising development. For hydrogen production systems integrated with renewable energy sources (RESs), alkaline electrolyzers (AELs), and energy storage devices, its energy management system (EMS) not only controls the RESs’ operating points to capture more renewable energy but also regulates the AELs and energy storage devices’ operating power to achieve dc bus voltage regulation, dynamic power sharing, power regulation of AELs, state-of-charge regulation of energy storage devices, etc. In this article, a decentralized EMS is proposed to achieve the above objectives. The proposed EMS can indirectly improve the system's efficiency and service life by ensuring that the AEL's operating power is always above the minimum recommended operating power and it only absorbs the low-frequency part of renewable power fluctuations. Besides, the proposed EMS can reduce system costs and enhance system reliability by eliminating communication networks. Furthermore, the operational principle of the proposed EMS and the system design and analysis are elaborated. The proposed EMS's effectiveness is verified by hardware-in-the-loop real-time simulations.

IMPORTANCE: The potential benefit of combining intracranial effective systemic therapy with radiotherapy for patients with breast cancer with brain metastases remains unclear. OBJECTIVE: To assess the activity and safety of combining radiotherapy with pyrotinib and capecitabine in patients with ERBB2-positive breast cancer and brain metastases. DESIGN, SETTING, AND PARTICIPANTS: This was a single-arm, single-center, phase 2 nonrandomized clinical trial with a safety run-in phase. Between January 2020 and August 2022, patients with ERBB2-positive breast cancer and brain metastases were enrolled. The data cutoff date was February 1, 2023. INTERVENTIONS: Patients received either fractionated stereotactic radiotherapy or whole-brain radiotherapy. Treatment with pyrotinib (400 mg, once daily) and capecitabine (1000 mg/m2, twice daily, on days 1-14 of each 21-day cycle) was initiated from the first day of radiotherapy to the seventh day after the completion of radiotherapy and continued until disease progression or unacceptable toxic effects. MAIN OUTCOMES AND MEASURES: The primary end point was 1-year central nervous system (CNS) progression-free survival (PFS) rate. Secondary end points included CNS objective response rate (ORR), PFS, overall survival (OS), safety, and changes in neurocognitive function. RESULTS: A total of 40 female patients (median age, 50.5 years [IQR, 46-59 years]) were enrolled and received treatment, including 3 patients in safety run-in phase. With a median follow-up of 17.3 months (IQR, 10.3-26.9), the 1-year CNS PFS rate was 74.9% (95% CI, 61.9%-90.7%), and the median CNS PFS was 18.0 months (95% CI, 15.5 to not reached). The 1-year PFS rate was 66.9% (95% CI, 53.1%-84.2%), and the median PFS was 17.6 months (95% CI, 12.8-34.1). The CNS objective response rate was 85% (34 of 40). Median overall survival was not reached. The most common grade 3 or 4 treatment-related adverse event was diarrhea (7.5%). Asymptomatic radiation necrosis was identified in 4 of 67 lesions (6.0%) treated with fractionated stereotactic radiotherapy. Most patients maintained neurocognitive function, as evaluated by the Mini-Mental State Examination at different points. CONCLUSIONS AND RELEVANCE: The results of this trial suggest that radiotherapy combined with pyrotinib and capecitabine is associated with long intracranial survival benefit in patients with ERBB2-positive advanced breast cancer and brain metastases with an acceptable safety profile. This combination deserves further validation. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04582968

ABSTRACTPopulation mobility may have a profound impact on the labor market, affecting firms’ employment decisions. We consider hukou reform in China as a quasi-natural experiment in identifying the effects of population mobility on employee-related corporate social responsibility (employee social responsibility, or ESR). The empirical results show that hukou reform prompts firms to invest more in ESR activities, particularly in ESR activities with weak externalities and in regions with a smaller labor market size. Cross-sectional tests suggest that the effects of hukou reform on firms’ ESR investment are stronger for more financially constrained firms and those in high-tech industries, and in more competitive regions. The findings have important practical implications for employment strategies that firms should adopt when the labor market becomes more competitive.

Efficient and convenient vulnerability detection for smart contracts is a key issue in the field of smart contracts. The earlier vulnerability detection for smart contracts mainly relies on static symbol analysis, which has high accuracy but low efficiency and is prone to path explosion. In this paper, the authors propose a static method for vulnerability detection based on deep learning. It first disassembles Ethereum smart contracts into opcode sequences and then converts the vulnerability detection problem into a natural language text classification problem. The word vector method is employed to map each opcode to a uniform vector space, and the opcode sequence matrix is trained by the TextCNN method to detect vulnerabilities. Furthermore, a code obfuscation method is given to enhance and balance the dataset, while three different opcode sequence generation methods are proposed to construct features. The experimental results verify that the average prediction accuracy of each smart contract exceeds 96%, and the average detection time is less than 0.1 s.

ABSTRACTThis study analyses how equity funds react to institutional pressure related to green finance. Based on the analysis of 378 open-end equity funds in China from 2010 to 2019, we examined the environmental performance of fund holdings to measure their level of green investment. In our analyses, we distinguished between funds with positive and negative screening strategies. Our results indicate that the funds’ green investments are gradually increasing. Furthermore, we found that green investment strategies help to increase the funds’ excess return. The positive connection to financial returns, however, is only valid for funds with negative screening strategies. Finally, we found that fund investors react negatively to funds using positive screening to identify green investments. The study contributes to theoretical and practical knowledge about factors influencing equity funds’ green and financial performance.

DC-link voltage control is of great importance for modular multilevel converter (MMC)-based high-voltage direct-current (HVDC) systems. Existing methods need to measure the actual dc-link voltage, which are referred to as direct control methods in this article and require a reliable dc voltage measuring device. The measurement system is complicated. Also, once malfunction occurs, dc-link voltage control may fail. This article aims to develop a dc-link voltage control method without actual voltage measurement. The idea is based on the coupling effect between dc-link voltage and submodule (SM) capacitor voltage. Based on the analysis, an indirect dc-link voltage control method is proposed. In this method, the existing dc-link voltage control loop is first replaced by the total capacitor voltage regulation control loop. Then, a compensation signal is introduced to the switching functions to mitigate undesired voltage deviation. Two approaches are proposed to generate a proper compensation signal. The proposed method can be integrated into the existing MMC control system. Also, in measurement failure cases, it can come into service and continue maintaining MMC dc-link voltage, improving system reliability. Both simulation and experimental results confirm the validity and effectiveness of the proposed method.

With the widespread use of network infrastructures such as 5G and low-power wide-area networks, a large number of the Internet of Things (IoT) device nodes are connected to the network, generating massive amounts of data. Therefore, it is a great challenge to achieve anonymous authentication of IoT nodes and secure data transmission. At present, blockchain technology is widely used in authentication and s data storage due to its decentralization and immutability. Recently, Fan et al. proposed a secure and efficient blockchain-based IoT authentication and data sharing scheme. We studied it as one of the state-of-the-art protocols and found that this scheme does not consider the resistance to ephemeral secret compromise attacks and the anonymity of IoT nodes. To overcome these security flaws, this paper proposes an enhanced authentication and data transmission scheme, which is verified by formal security proofs and informal security analysis. Furthermore, Scyther is applied to prove the security of the proposed scheme. Moreover, it is demonstrated that the proposed scheme achieves better performance in terms of communication and computational cost compared to other related schemes.

Solar interfacial evaporation (SIE) is an eco-friendly and sustainable technology for addressing water pollution and freshwater scarcity. However, treating wastewater containing volatile organic compounds and heavy metal ions with a single SIE method is inefficient. The combination of adsorption, coagulation, and evaporation process provides an alternative solution for treating this type of wastewater. In this study, activated carbon powder (C) is introduced as an adsorbent and an integral part of photothermal conversion material, which is coagulated with polyvinyl alcohol (PVA) and polyethylene glycol (PEG) through a mold press process to fabricate PVA/C/PEG composite hydrogels. The volatile organic compounds and heavy metal ions in the wastewater are adsorbed by the activated carbon powder and the wastewater is then further purified into freshwater through SIE. This stepwise “adsorption first, then coagulation and evaporation” method can not only rapidly remove pollutants from the raw water, but also provides a much higher removal efficiency than the adsorption-evaporation synergetic process. This work demonstrates a successful attempt to utilize the SIE method for treating wastewater containing volatile organic compounds and heavy metal ions.

A series of fully fused n-type mixed conduction lactam polymers p(g7NCnN), systematically increasing the alkyl side chain content, are synthesized via an inexpensive, nontoxic, precious-metal-free aldol polycondensation. Employing these polymers as channel materials in organic electrochemical transistors (OECTs) affords state-of-the-art n-type performance with p(g7NC10N)recording an OECT electron mobility of 1.20 × 10–2cm2V–1s–1and a μC* figure of merit of 1.83 F cm–1V–1s–1. In parallel to high OECT performance, upon solution doping with (4-(1,3-dimethyl-2,3-dihydro-1H-benzoimidazol-2-yl)phenyl)dimethylamine (N-DMBI), the highest thermoelectric performance is observed for p(g7NC4N), with a maximum electrical conductivity of 7.67 S cm–1and a power factor of 10.4 μW m–1K–2. These results are among the highest reported for n-type polymers. Importantly, while this series of fused polylactam organic mixed ionic–electronic conductors (OMIECs) highlights that synthetic molecular design strategies to bolster OECT performance can be translated to also achieve high organic thermoelectric (OTE) performance, a nuanced synthetic approach must be used to optimize performance. Herein, we outline the performance metrics and provide new insights into the molecular design guidelines for the next generation of high-performance n-type materials for mixed conduction applications, presenting for the first time the results of a single polymer series within both OECT and OTE applications.

In vitrostudies have established the prevalent theory that the mitochondrial kinase PINK1 protects neurodegeneration by removing damaged mitochondria in Parkinson’s disease (PD). However, difficulty in detecting endogenous PINK1 protein in rodent brains and cell lines has prevented the rigorous investigation of the in vivorole of PINK1. Here we report that PINK1 kinase form is selectively expressed in the human and monkey brains. CRISPR/Cas9-mediated deficiency of PINK1 causes similar neurodegeneration in the brains of fetal and adult monkeys as well as cultured monkey neurons without affecting mitochondrial protein expression and morphology. Importantly, PINK1mutations in the primate brain and human cells reduce protein phosphorylation that is important for neuronal function and survival. Our findings suggest that PINK1 kinase activity rather than its mitochondrial function is essential for the neuronal survival in the primate brains and that its kinase dysfunction could be involved in the pathogenesis of PD.

Conjugated polymers achieve redox activity in electrochemical devices by combining redox-active, electronically conducting backbones with ion-transporting side chains that can be tuned for different electrolytes. In aqueous electrolytes, redox activity can be accomplished by attaching hydrophilic side chains to the polymer backbone, which enables ionic transport and allows volumetric charging of polymer electrodes. While this approach has been beneficial for achieving fast electrochemical charging in aqueous solutions, little is known about the relationship between water uptake by the polymers during electrochemical charging and the stability and redox potentials of the electrodes, particularly for electron-transporting conjugated polymers. We find that excessive water uptake during the electrochemical charging of polymer electrodes harms the reversibility of electrochemical processes and results in irreversible swelling of the polymer. We show that small changes of the side chain composition can significantly increase the reversibility of the redox behavior of the materials in aqueous electrolytes, improving the capacity of the polymer by more than one order of magnitude. Finally, we show that tuning the local environment of the redox-active polymer by attaching hydrophilic side chains can help to reach high fractions of the theoretical capacity for single-phase electrodes in aqueous electrolytes. Our work shows the importance of chemical design strategies for achieving high electrochemical stability for conjugated polymers in aqueous electrolytes.

The vehicle fuel consumption gauge is a vehicle's basic device that usually records the instantaneous as well as average fuel consumption of the vehicle, which brings a lot of convenience during the driving process. The individual real-time fuel consumption data are meaningless, but its continuous real-time fuel consumption data contains some information that may reveal the user's privacy, which is sensitive information for users. There are hot topics on privacy protection of sensitive user information, however, most of the studies have focused on privacy protection at the time of data release and the need for a trusted third party. In this paper, we propose a negative survey-based approach that can be utilized to protect aggregated vehicle fuel consumption data against time-series-based differential attacks. Its anonymous algorithm on the user side and estimation algorithm on the server side are able to protect the user's privacy regardless of changes in the user's fuel consumption data. The experiment results show that our method can achieve better privacy protection with better application prospects in a simpler and more effective way. [ABSTRACT FROM AUTHOR]

Postnatal colonization and development of the gut microbiota is linked to health and growth. A comprehensive understanding of the postnatal compositional changes and development of the microbial community is helpful to understand the gut health and improve the survival rate of South China tiger cubs (Panthera tigris amoyensis). Fecal samples from three tiger cubs were collected on the day of birth in 2018 (June 17–21 [G0], July 18 [G1], July 31 [G2], and August 7 [G3]). The 16S rRNA genes of the fecal microflora were sequenced. Results showed that 38 phyla, 58 classes, 134 orders, 272 families, and 636 genera of bacteria from 3,059 operational taxonomic units were identified from 12 fecal samples. The diversity and abundance of species of group G0 were significantly higher (p< 0.05 or 0.01) than those of groups G2 and G3. The predominant phylum was Proteobacteria in groups G0 and G1 (38.85% and 48%, respectively) and Firmicutes in groups G2 and G3 (71.42% and 75.29%, respectively). At the phylum level, the abundance of Deinococcus-Thermus was significantly decreased in groups G1, G2, and G3 as compared to group G0 (p< 0.05), while that of Firmicutes was significantly increased in groups G2 and G3 (p< 0.05). At the genus level, the abundance of Faecalibacterium, Ralstonia, and unidentified Rickettsialeswas significantly decreased in groups G1, G2, and G3 as compared with group G0 (p< 0.05), while that of Pseudomonaswas significantly decreased in groups G2 and G3 (p< 0.05). The composition and structure of fecal microbiota of South China tiger cubs changed after birth.

On-chip imaging flow cytometry has been widely used in cancer biology, immunology, microbiology, and drug discovery. Pure optical imaging combined with flow cytometry to derive chemical, structural, and morphological features of cells provides systematic insights into biological processes. However, due to the high concentration and strong optical attenuation of red blood cells, preprocessing is necessary for optical flow cytometry while dealing with whole blood. In this study, we develop an on-chip photoacoustic imaging flow cytometry (PAIFC), which combines multicolor high-speed photoacoustic microscopy and microfluidics for cell imaging. The device employs a micro-optical scanner to achieve a miniaturized outer size of 30 × 17 × 24 mm3and ultrafast cross-sectional imaging at a frame rate of 1758 Hz and provides lateral and axial resolutions of 2.2 and 33 μm, respectively. Using a multicolor strategy, PAIFC is able to differentiate cells labeled by external contrast agents, detect melanoma cells with an endogenous contrast in whole blood, and image melanoma cells in blood samples from tumor-bearing mice. The results suggest that PAIFC has sufficient sensitivity and specificity for future cell-on-chip applications.

Traditional energy resource i.e. natural coal is used to develop high-performance bifunctional oxygen electrodes in renewable energy conversion systems.

Nano molding technology (NMT) has shown great potential in the preparation of metal/resin composites, which can integrate resin and metal into a lightweight, high-strength metal matrix composite. However, due to the poor interfacial bonding strength between metal and polymer, the application of the metal/polymer composites is limited. In this paper, we proposed a novel method to improve the bonding strength between Fe–Co–Ni alloy and epoxy resin by Nano Perfusion Technology (NPT), featuring in situgrowth of carbon nanotubes (CNTs) in the pores on anodized Fe–Co–Ni alloy porous surface, followed by a perfusion of epoxy resin throughout the pores that had been in situgrown CNTs. Due to the “anchor effect” of CNTs, the bonding strength between the epoxy and the alloy matrix is improved. The results showed that the interfacial bonding between the in situCNTs-modified alloy and the resin was significantly improved compared to the metal-resin composites surface treated with T-treatment in traditional method of NMT. The maximum interfacial bonding force of the alloy-CNTs/epoxy composite reached up to 691.80 N, which was 460, 315, and 267% higher than those by mechanical treatment, without CNTs and T-treatment, respectively. This work provides a new approach to protect metals or alloys from environmental corrosion, impact damage, and so on.

Hard carbon materials have gained extensive utilization in energy storage systems because of their stable chemical properties, unique lamellar arrangement, and significant interlayer spacing. In this study, we present a novel porous carbon electrode based on hard carbon to enhance the performance of a solid-state symmetric supercapacitor. This electrode was fabricated through an efficient and straightforward synthetic approach using natural asphalt as the precursor. The resulting carbon electrode exhibits remarkable features including a large surface area (2334.48 m2 g−1), a well-distributed pore size (mesopore ratio of 16.04 %), an appropriate oxygen content (18.11 %), and a lamellar structure. As a result, the as-prepared carbon electrode demonstrates a high specific capacitance of 325.82 F g−1at 0.5 A g−1, along with excellent rate capability, with coulombic efficiency ranging from 99.89 % at 0.5 A g−1to 98.92 % at 10 A g−1. Moreover, the assembled symmetrical all-solid-state supercapacitor utilizing this electrode achieves an energy density of 18.91 Wh Kg−1, an equivalent series resistance of 0.820 Ω, a relaxation time of 9.0 s, and self-discharge performance lasting up to 72 h. Notably, owing to its large layer spacing (0.391 nm), the electric double layer capacitor contributes as much as 94 %, indicating favorable electrical double layer characteristics. Our work not only showcases a high-performance electrode material but also contributes to the expanded application of hard carbon.

Currently, in situmonitoring of the adenosine triphosphate (ATP) level in lysosomes is critical to understand their involvement in various biological processes, but it remains difficult due to the interferences of limited targeting and low resolution of fluorescent probes. Herein, we report a classic Mn(II) probe (FX2-MnCl2) with near-infrared (NIR) nonlinear (NLO) properties, accompanied by three–four photon transition and fivefold fluorescence enhancement in the presence of ATP. FX2-MnCl2combines with ATP through dual recognition sites of diethoxy and manganese ions to reflect slightly fluorescence lifetime change. Through the synergy of multiphoton fluorescence imaging (MP-FI) and multiphoton fluorescence lifetime imaging microscopy (MP-FLIM), it is further demonstrated that FX2-MnCl2displays lysosome-specific targeting behavior, which can monitor lysosome-related ATP migration under NIR laser light. This work provides a novel multiphoton transformation fluorescence complex, which might be a potential candidate as a simple and straightforward biomarker of lysosome ATP in vitrofor clinical diagnosis.

The tight regulation of the glucose concentration in the body is crucial for balanced physiological function. We developed an electrochemical transistor comprising an n-type conjugated polymer film in contact with a catalytic enzyme for sensitive and selective glucose detection in bodily fluids. Despite the promise of these sensors, the property of the polymer that led to such high performance has remained unknown, with charge transport being the only characteristic under focus. Here, we studied the impact of the polymer chemical structure on film surface properties and enzyme adsorption behavior using a combination of physiochemical characterization methods and correlated our findings with the resulting sensor performance. We developed five n-type polymers bearing the same backbone with side chains differing in polarity and charge. We found that the nature of the side chains modulated the film surface properties, dictating the extent of interactions between the enzyme and the polymer film. Quartz crystal microbalance with dissipation monitoring studies showed that hydrophobic surfaces retained more enzymes in a densely packed arrangement, while hydrophilic surfaces captured fewer enzymes in a flattened conformation. X-ray photoelectron spectroscopy analysis of the surfaces revealed strong interactions of the enzyme with the glycolated side chains of the polymers, which improved for linear side chains compared to those for branched ones. We probed the alterations in the enzyme structure upon adsorption using circular dichroism, which suggested protein denaturation on hydrophobic surfaces. Our study concludes that a negatively charged, smooth, and hydrophilic film surface provides the best environment for enzyme adsorption with desired mass and conformation, maximizing the sensor performance. This knowledge will guide synthetic work aiming to establish close interactions between proteins and electronic materials, which is crucial for developing high-performance enzymatic metabolite biosensors and biocatalytic charge-conversion devices.

Microwave-absorbing materials with good microwave absorption performance are of great interest for military applications and human health, which is threatened by electromagnetic radiation pollution. Herein, the design and synthesis of multi-componential metal-hybridized graphene composites via freeze drying and pyrolysis of ferrocene hydrazone complex precursor are reported. Various magnetic nanoparticles are loaded on reduced graphene oxide (rGO) via controlling their pyrolysis temperature. The complex electromagnetic parameters of these hybrids are therefore regulated by the hybrid components. Among them, rGO hybridized by the sea-island-like Fe2O3/Fe3O4/FeNi3multi-componential metals shows a good balance of dielectric and magnetic constants. Thus, the improved impedance matching with free space brings about a superior electromagnetic wave absorption performance, especially on the effective absorption bandwidth. The minimum reflection loss (RL) of the hybrids is as low as −40.3 dB at 11 GHz with the RL bandwidth of −10 dB being 4.55 GHz (from 9.25 to 13.8 GHz).

Flexible dielectrics with high energy density (Ue) and low energy loss (Ul) under elevated electric fields are especially attractive for the next-generation energy storage devices, e.g., high-pulse film capacitors. However, raising Ueby introducing high dielectric constant materials generally increases Ul, which is detrimental to the devices. To overcome this trade-off, a new strategy consisting of elevating electron polarization through the incorporation of 4-hydroxy-2,2,6,6-tetramethylpiperidin-N-oxy (TEMPO) units and capturing electrons with stable organic radicals is proposed. A series of flexible poly (dicyclopentadiene norbornene-ended 4-hydroxy-2, 2, 6, 6-tetramethylpiperidin-N-oxy) (PNB-DxTy) copolymers with excellent dielectric and physical properties, thermal stability, and processability, were prepared and their energy storage properties investigated. Specifically, dicyclopentadiene (DCPD) groups were designed to construct a cross-linked network, while the TEMPO groups offered a stable radical to capture electrons under the action of an electric field, which favored the enhancement of the dielectric constant, Young’s modulus, and breakdown strength of the polymers. Compared with commercially available state-of-the-art polymer dielectrics, e.g., biaxially oriented polypropylene (BOPP), PNB-Dx-Tydemonstrated an exceeding dielectric performance and low-cost potential. Importantly, a discharge energy density of 10.6 J/cm3with a high efficiency of 92% at 500 MV/m was achieved. The effective strategy revealed that the isolated stable radical in the low-polarity polymer matrix suppressed the energy loss and created a new paradigm for high-energy and low-loss flexible capacitors.

The development of adhesives with superior optical and mechanical performance, solvent resistance, and reworkability is gaining increasing attention in recent years. However, traditional materials do not possess reprocessability and healing characteristics for sustainable development. Here, a superior dynamic polythiourethane (PTU) adhesive with high reprocessability was developed by introducing covalent adaptable networks (CANs). Specifically, dynamic thiocarbamate bonds (TCB) were used to prepare PTU CANs, which showed dramatically enhanced malleability and recyclability. The Young’s modulus of the material was 2.0 GPa and the tensile strength was 62.7 MPa. The reprocessing temperature of CANs was reduced to 80 °C while more than 90% of their mechanical properties were retained, even after being reprocessed several times. Moreover, the highly transparent and water-resistant PTU CANs featured an excellent bonding property and reworkability for various materials including glass, with a lap shear strength of 2.9 MPa, metal (5.1 MPa), and wood (6.3 MPa), compared with commercially available adhesives. Additionally, carbon fiber-reinforced composites constructed with PTU CANs were capable of being fully recycled and reused. Importantly, laminated glass with a toughened PTU–PU elastomer interface exhibited an outstanding impact fatigue-resistance behavior, sustaining thousands of impacts. These features demonstrate that PTU CANs show great potential as sustainable materials.

Development of a physical barrier with mechanical properties similar to human smooth muscle and an on-demand degradation profile is crucial for the clinical prevention of postoperative adhesion. Herein, a series of supramolecular hydrogels (PMI hydrogels) composed of poly(ethylene glycol) (PEG), methylenediphenyl 4, 4-diisocyanate (MDI), and imidazolidinyl urea (IU, hydrogen bonding reinforced factor) with biodegradability and high toughness are reported to serve as physical barriers for abdominal adhesion prevention. The tensile fracture strength and strain of the PMI hydrogels could be adjusted in the ranges of 0.6–2.3 MPa and 100–440%, respectively, and their Young’s moduli (0.2–1.6 MPa) are close to that of human soft tissues like smooth muscle and skin tissue as well as they have outstanding shape memory properties. The PMI hydrogels show good cell and tissue biocompatibility, and the in vivo retention time is in accord with the needs for the postoperative antiadhesion physical barriers. Through an abdominal defect model on mice, this study shows that the PMI hydrogel can completely prevent tissue adhesion compared to the commercialized Seprafilm with high safety. Owing to the promising mechanical properties and good biocompatibility, the PMI hydrogels may be extended for various biomedical applications and the development of advanced flexible electronic devices.

High-temperature coal tar pitch is often used to produce high-quality needle coke. Its basic properties [such as favalue, β resin, and quinoline insoluble (QI) content] significantly affect the quality of the resulting needle coke. Refined pitch with faand β-resin values in the 0.95–0.98 and 13–16% ranges, respectively, is considered an excellent raw material for this purpose. The influence of QI content on the characteristics of coal-based needle coke is still not fully clarified in the literature. To analyze how QI content affects coal-based needle coke properties, this work used 10 different kinds of coal tar pitch (refined from the same source) with different QI contents for the needle coke production. We thoroughly analyzed optical microstructure and crystalline sizes, surface morphology and microstrength, true density, and coefficient of thermal expansion (CTE) of the resulting products. The high-temperature coal tar pitch with the QI content of <0.8% was a preferable raw material to obtain superior needle coke; it possessed higher density and microstrength, lower CTE, and graphitized more easily than cokes with other parameters.

Ensuring material performance reliability and lifetime is crucial for practical operations. Small cracks on the material surface are often detrimental to its safe operation. This study describes the development of a hydrogen bond-rich puncture-resistant polyurethane elastomer with supertoughness. The as-prepared polyurethane transparent films feature high tensile break strength (57.4 MPa) and great toughness (228 MJ m–3). Additionally, a facile, low-cost, crack self-diagnostic approach through photoluminescence using a small luminous pen is reported. The materials efficiently achieved self-healing at 90 °C after the crack formation. The change of fluorescence intensity on the crack can be used to track the self-healing process. Therefore, this work provides a guideline for the material design of supertough, puncture-resistant, transparent, and healable elastomers and a crack self-diagnosis and healing approach.

A promising class of materials for applications that rely on electron transfer for signal generation are the n-type semiconducting polymers. Here we demonstrate the integration of an n-type conjugated polymer with a redox enzyme for the autonomous detection of glucose and power generation from bodily fluids. The reversible, mediator-free, miniaturized glucose sensor is an enzyme-coupled organic electrochemical transistor with a detection range of six orders of magnitude. This n-type polymer is also used as an anode and paired with a polymeric cathode in an enzymatic fuel cell to convert the chemical energy of glucose and oxygen into electrical power. The all-polymer biofuel cell shows a performance that scales with the glucose content in the solution and a stability that exceeds 30 days. Moreover, at physiologically relevant glucose concentrations and from fluids such as human saliva, it generates enough power to operate an organic electrochemical transistor, thus contributes to the technological advancement of self-powered micrometre-scale sensors and actuators that run on metabolites produced in the body.

Synthesis of silver nanoparticles (Ag NPs) with state-of-the-art chemical or photo-reduction methods generally takes several steps and requires both reducing agents and stabilizers to obtain NPs with narrow size distribution. Herein, we report a novel method to synthesize Ag NPs rapidly in one step, achieving typical particle sizes in the range from 5 to 15 nm. The synthesis steps only involve three chemicals without any reducing agent: AgNO3as precursor, polyvinylpyrrolidone (PVP) as stabilizer, and AgCl as photocatalyst. The Ag NPs were supported on carbon and showed excellent performance in thermal catalytic p-nitrophenol reduction and nitrobenzene hydrogenation, and as electrocatalyst for the oxygen reduction reaction.

The evident demand for hydrogen as the ultimate energy fuel for posterity calls for the development of low-cost, efficient and stable electrocatalysts for water splitting. Herein, we report the synthesis of Co/CoOx supported on coal-derived N-doped carbon via a simple microwave-assisted method and demonstrate its application as an efficient catalyst for the oxygen evolution reaction (OER). With the optimal amount of cobalt introduced into the N-doped coal-derived, the developed catalyst achieved overpotentials of 0.370 and 0.429 V during water oxidation at current densities of 1 mA cm[?]2 and 10 mA cm[?]2, respectively. There was no noticeable loss in the activity of the catalyst during continuous galvanostatic polarization at a current density of 10 mA cm[?]2 for a test period of 66 h. The synergistic interaction of the Co/CoOx moieties with the pyridinic and pyrollic nitrogen functional groups in the N-doped carbon, as well with the other heteroatoms species in the pristine coal favored enhancement of the OER electrocatalytic performance.

Novel superhydrophilic inorganic-based N-halamine nanofibrous membranes with high active chlorine contents, outstanding rechargeability, favorable water swelling resistance, and superior mechanical performance were prepared through the combination of electrospinning and sol–gel processing, which could be applied to the dynamic disinfection of bacteria-contaminated water with high disinfection efficiency, large processing flux, and long-term durability. The successful preparation of such silica nanofiber membranous N-halamine antimicrobial with intriguing properties would provide the reference for developing novel antimicrobial nanofibers for multifunctional applications.

Despite metal-air batteries possessing very high theoretical energy densities, inefficient reversibility of the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) at the oxygen electrode undermines their rechargeability, which has slowed their market entry. Herein, we demonstrate a simple procedure for synthesis of a hybrid of MnO and metallic Co supported on N-doped graphene that exhibits activity and stability as a bifunctional ORR/OER catalyst, with a round trip ORR/OER overvoltage of 0.85 V, which remained constant for at least 70 h when cycling alternately, between oxygen evolution at a current density of 10 mA cm[?]2 and oxygen reduction at [?]1 mA cm[?]2. Insights into the key properties of the catalyst that influence its performance are proposed based on structural characterization by TEM, SEM, Raman spectroscopy, XRD and XPS. Besides MnO and metallic Co as the predominant crystalline species in the Co-Mn hybrid oxide, XPS revealed Mn3O4 and CoO rich surfaces, ascribed to oxidation of MnO and metallic Co due to atmospheric exposure. The synergetic interaction between the Co-Mn hybrid oxides and N-doped graphene, as well as Co-Mn interaction, favor improved ORR, OER and bifunctional ORR/OER performance of the catalyst.

Differences in activity limitations between stroke survivors and people with other chronic conditions and how their levels of activity limitation vary by sociodemographic characteristics have not been well quantified.

The plasmonic resonances in individual gold nanorods nanoscopically coupled to a gold film with different gap spacing have been experimentally and theoretically investigated. The spectral widths, wavelengths, and optical polarizabilities of the maxima in measured single-nanoparticle scattering spectra are significantly modified as the gap distance changes in the sub-20 nm domain. Comparing the experimental data with numerical simulations reveals that these modifications arise from the complex hybridization of several dipolar and multipolar plasmon modes that are strongly localized at the gap. These plasmon gap modes have distinct resonant and spatial characteristics as a result of near-field interaction between the elongated nanorods and the gold film. Additionally, the excitation of these gap modes is highly dependent on the gap spacing. Finally, we also discuss influences of these plasmonic modes on absorption properties of the system and propose a potential application of the studied structures in facilitating photothermal conversion.

Graphite electrodes were modified with specifically designed Os-complex modified electrodeposition polymers exhibiting a formal potential of the polymer-bound complex of about 0 to 20 mV (vs. Ag/AgCl/3 M KCl) which is only about 100 mV anodic of the formal potential of pyrroloquinoline quinone (PQQ) in PQQ-dependent glucose dehydrogenase (PQQ-GDH). The efficiency of wiring the polymer-entrapped PQQ-GDH was dependent on the nature of the polymer backbone, the crosslinking with bifunctional crosslinkers and the co-entrapment of multi-walled carbon nanotubes. Due to the limited long-term stability a new polymer synthesis strategy was adapted using the same Os-complex but providing enhanced crosslinking capabilities by introducing epoxide functions at the polymer backbone. Related bioelectrodes showed enhanced glucose-dependent current and a stability of at least 3 days of continuous operation.

In order to locally analyse catalytic activity on modified surfaces a transient redox competition mode of scanning electrochemical microscopy (SECM) has been developed. In a bi-potentiostatic experiment the SECM tip competes with the sample for the very same analyte. This leads to a current decrease at the SECM tip, if it is positioned in close proximity to an active catalyst site on the surface. Specifically, local catalytic activity of a Pt-catalyst modified sample with respect to the catalytic reduction of molecular oxygen was investigated. At higher local catalytic activity the local O2 partial pressure within the gap between accurately positioned SECM tip and sample is depleted, leading to a noticeable tip current decrease over active sites. A flexible software module has been implemented into the SECM to adapt the competition conditions by proper definition of tip and sample potentials. A potential pulse profile enables the localised electrochemically induced generation of molecular oxygen prior to the competition detection. The current decay curves are recorded over the entire duration of the applied reduction pulse. Hence, a time resolved processing of the acquired current values provides movies of the local oxygen concentration against x,y-position. The SECM redox competition mode was verified with a macroscopic Pt-disk electrode as a test sample to demonstrate the feasibility of the approach. Moreover, highly dispersed electro-deposited spots of gold and platinum on glassy carbon were visualised using the redox competition mode of SECM. Catalyst spots of different nature as well as activity inhomogeneities within one spot caused by local variations in Pt-loading were visualised successfully.

The treatment of diabetic chronic wounds remains a global challenge due to the up-regulated inflammation response, oxidant stress, and persistent infection during healing process. Developing wound dressing materials with ideal biocompatibility, adequate mechanical strength, considerable under-water adhesion, sufficient anti-inflammation, antioxidant, and antibacterial properties is on-demand for clinical applications. In this study, we developed a bioactive skin-mimicking hydrogel band-aid through the combination of tannic acid (TA) and imidazolidinyl urea reinforced polyurethane (PMI) (TAP hydrogel) and explored its potentials in various medical applications, including hemostasis, normal skin incision, full-thickness skin wounds, and bacterial-infection skin incision on diabetic mice. TA was loaded into PMI hydrogel network to enhance the mechanical properties of TAP hydrogels through multiple non-covalent interactions (break strength: 0.28–0.64 MPa; elongation at break: 650–930%), which could resist the local stress and maintain the structural integrity of wound dressings during applications. Moreover, owing to the promising moisture-resistant adhesiveness and organ hemostasis, outstanding anti-inflammation, antibacterial, and antioxidant properties, TAP hydrogels could efficiently promote the recovery of skin incision and defects on diabetic mice. To further simulate the practical situation and explore the potential in clinical application, we also verified the treatment efficiency of TAP hydrogel in S. aureus-infected skin incision model on diabetic mice.

Turning the surfaces of noble metals (metasurfaces) into black (highly absorptive) surfaces can be potentially applied in thermophotovoltaics, sensing, tailoring thermal emissivity, etc. Here we demonstrate an extremely broadband absorber for the 900–1600 nm wavelength range with robust high absorption efficiency. The inexpensive droplet evaporation method is implemented to create patterns of nanoparticles dispersed on a gold film spaced by a thin dielectric layer. The diversity of the complicated random stacking of the chemically synthesized gold nanorods is the major factor for the broad absorption band. Such a metamaterial absorber may pave the way for cost-effective manufacture of large-area black metasurfaces.

The evident demand for hydrogen as the ultimate energy fuel for posterity calls for the development of low-cost, efficient and stable electrocatalysts for water splitting. Herein, we report the synthesis of Co/CoOxsupported on coal-derived N-doped carbon via a simple microwave-assisted method and demonstrate its application as an efficient catalyst for the oxygen evolution reaction (OER). With the optimal amount of cobalt introduced into the N-doped coal-derived, the developed catalyst achieved overpotentials of 0.370 and 0.429 V during water oxidation at current densities of 1 mA cm−2and 10 mA cm−2, respectively. There was no noticeable loss in the activity of the catalyst during continuous galvanostatic polarization at a current density of 10 mA cm−2for a test period of 66 h. The synergistic interaction of the Co/CoOxmoieties with the pyridinic and pyrollic nitrogen functional groups in the N-doped carbon, as well with the other heteroatoms species in the pristine coal favored enhancement of the OER electrocatalytic performance.

The study compares the physical and biologically effective doses (BED) received by the heart and cardiac substructures using three-dimensional conformal RT (3D-CRT), intensity-modulated radiotherapy (IMRT), and simple IMRT (s-IMRT) in postoperative radiotherapy for patients with left-sided breast cancer.