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Identification of the acoustic environment from an audio recording, also known as acoustic scene classification, is an active area of research. In this paper, we study dynamically-changing background acoustic scenes from the egocentric perspective of an individual in a workplace. In a novel data collection setup, wearable sensors were deployed on individuals to collect audio signals within a built environment, while Bluetooth-based hubs continuously tracked the individual's location which represents the acoustic scene at a certain time. The data of this paper come from 170 hospital workers gathered continuously during work shifts for a 10 week period. In the first part of our study, we investigate temporal patterns in the egocentric sequence of acoustic scenes encountered by an employee, and the association of those patterns with factors such as job-role and daily routine of the individual. Motivated by evidence of multifaceted effects of ambient sounds on human psychology, we also analyze the association of the temporal dynamics of the perceived acoustic scenes with particular behavioral traits of the individual. Experiments reveal rich temporal patterns in the acoustic scenes experienced by the individuals during their work shifts, and a strong association of those patterns with various constructs related to job-roles and behavior of the employees. In the second part of our study, we employ deep learning models to predict the temporal sequence of acoustic scenes from the egocentric audio signal. We propose a two-stage framework where a recurrent neural network is trained on top of the latent acoustic representations learned by a segment-level neural network. The experimental results show the efficacy of the proposed system in predicting sequence of acoustic scenes, highlighting the existence of underlying temporal patterns in the acoustic scenes experienced in workplace.

Two-dimensional polyimide covalent organic framework (2D PI-NT COF) films were constructed on indium tin oxide-coated glass substrates to fabricate two-terminal sandwiched resistive memory devices. The 2D PI-NT COF films condensated from the reaction between 4,4′,4″-triaminotriphenylamine and naphthalene-1,4,5,8-tetracarboxylic dianhydride under solvothermal conditions demonstrated high crystallinity, good orientation preference, tunable thickness, and low surface roughness. The well-aligned electron-donor (triphenylamine unit) and -acceptor (naphthalene diimide unit) arrays rendered the 2D PI-NT COF films a promising candidate for electronic applications. The memory devices based on 2D PI-NT COF films exhibited a typical write-once-read-many-time resistive switching behavior under an operating voltage of +2.30 V on the positive scan and −2.64 V on the negative scan. A high ON/OFF current ratio (>106for the positive scan and 104–106for the negative scan) and long-term retention time indicated the high fidelity, low error, and high stability of the resistive memory devices. The memory behavior was attributed to an electric field-induced intramolecular charge transfer in an ordered donor–acceptor system, which provided the effective charge-transfer channels for injected charge carriers. This work represents the first example that explores the resistive memory properties of 2D PI-COF films, shedding light on the potential application of 2D COFs as information storage media.

Schottky-barrier field-effect transistors (SBFETs) based on multilayer WS2with Au as drain/source contacts are fabricated in this paper. Interestingly, the novel polarity behavior of the WS2SBFETs can be modulated by drain bias, ranging from p-type to ambipolar and finally to n-type conductivity, due to the transition of band structures and Schottky-barrier heights under different drain and gate biases. The electron mobility and the on/off ratio of electron current can reach as high as 23.4 cm2/(V s) and 8.5 × 107, respectively. Moreover, the WS2SBFET possesses high-performance photosensitive characteristics with response time of 40 ms, photoresponsivity of 12.4 A/W, external quantum efficiency of 2420%, and photodetectivity as high as 9.28 × 1011cm Hz1/2/W. In conclusion, the excellent performance of the WS2SBFETs may pave the way for next-generation electronic and photoelectronic devices.

Reactive oxygen species (ROS) have emerged as a promising treatment option for antibacterial and biofilm eradication. However, their therapeutic efficacy is significantly hampered by the unique microenvironments of diabetic wounds. In this study, we designed and synthesized porphyrin-based Fe covalent organic frameworks (Fe-COF) through a Schiff base condensation reaction. Subsequently, Fe-COF were encapsulated with hyaluronic acid (HA) through electrostatic adsorption, resulting in a novel formulation named HA-Fe-COF for diabetic wound healing. HA-Fe-COF were engineered to respond to hyaluronidase in the infected wound, leading to the controlled release of Fe-COF. Those released Fe-COF served a dual role as photosensitizers, generating singlet oxygen and localized heating when exposed to dual light sources. Additionally, they acted as peroxidase-like nanozymes, facilitating the production of ROS through enzymatic reactions. This innovative approach enabled a synergistic therapeutic effect combining photodynamic, photothermal, and chemodynamic modalities. Furthermore, the sustained release of HA from HA-Fe-COF promoted angiogenesis, collagen deposition, and re-epithelialization during the diabetic wound healing process. This “all-in-one” strategy offers a novel approach for the development of antimicrobial and biofilm eradication strategies that minimize damage to healthy tissues in vivo.

Metal–covalent organic frameworks (MCOFs) feature regular structures, adjustable pore channels, designable structures, and abundant tunable metal-catalytic active sites and are promising candidates for advanced single-atom enzymes. Here, we constructed porous and crystalline Fe-COFTAPB-BPAlinked with Fe-iminopyridine moieties from the corresponding building blocks under ambient conditions in the time scale of minutes. Fe-COFTAPB-BPAwith single-atom Fe dispersion could react with H2O2to catalyze the oxidation of tetramethylbenzidine (TMB), demonstrating that an MCOF with a well-defined metallo ligand structure can function as a single-atom enzyme. Steady-state kinetic analysis showed that crystalline Fe-COFTAPB-BPArevealed a higher affinity to TMB than amorphous Fe-PolyTAPB-BPAat a similar Fe content attributed to its regular pore structure, higher specific surface area, and uniform distribution of catalytically active sites. As a peroxidase mimetic, Fe-COFTAPB-BPAexhibits the advantages of easy preparation, good stability, and higher catalytic efficiency.

Detection of radioactive iodide ions (I–) is important for protecting human beings from the hazards of radioactive pollution. Herein, we present a protocol for detecting I–using a zirconium(IV)-enhanced strategy. We describe steps for optimizing the I–detection approach, establishing standard curves, and finally applying the approach. The use of zirconium(IV) greatly improves the detection performance and endows this approach with an ultralow detection limit of 0.176 nM together with wide applicability in various aqueous environments.

This study deals with the influences of both the length of the aliphatic spacer within the phthalonitrile monomers backbones, and the amount of the silane surface modified zirconia nanoparticles on the mechanical and thermal properties of the so-called second generation phthalonitrile resins. Investigation on the curing behavior under differential scanning calorimeter outlined an important gain in the processability as the aliphatic spacer became longer. Results from the mechanical tests revealed that changing the length of the aliphatic spacer affects the mechanical properties in different ways. For instance, as the aliphatic spacer became longer, the toughness state was enhanced. At the same time, the tensile modulus and stress as well as the microhardness values were slightly reduced. It was also noticed that the introduction of the reinforcing phase caused an increase in all the tested mechanical properties. Furthermore, results from the thermogravimetric analysis and dynamic mechanical analysis revealed that reducing the length of the aliphatic spacer and adding nanofillers caused an increase in the thermal stability, storage modulus, and glass transition temperature. Moreover, a morphological study has been conducted under scanning electron microscope and transmission electron microscope to put in light the mechanisms of enhancements. Finally, this study demonstrated that the excellent properties of the phthalonitrile resins can be tailored by two ways either by monomers design or by inorganic nanoparticles reinforcement.

Considering the stability and hazard of chromium complexes, their removal and recovery from industrial wastewater is a worthy goal. Membrane capacitive deionization (MCDI) can effectively reduce co-ion adsorption compared with CDI technology and has been demonstrated to be a promising deionization technology. In this study, functionalized activated carbon (AC@SiO2-NH2) was applied as a MCDI eletrode. The AC@SiO2-NH2adsorbs chromium complexes (Cr(Ⅲ)-EDTA) through electrostatic gravitation of protonated amino groups (-NH3+). With applied voltage of 1.2 V, solution flow rate of 20 mL min−1and initial concentration of 300 mg L−1, the electrosorption capacity of the AC@SiO2-NH2electrode for Cr(Ⅲ)-EDTA was 17.70 mg g−1. The Ragone curves verified that the electrosorption rate (SER) of the AC@SiO2-NH2electrode was positively correlated with voltage and initial concentration. Moreover, the effects of competing ions (K+, Na+, and Mg2+) in a series of single electrolyte solution by the AC@SiO2-NH2electrode were investigated. It was also verified that the optimum pH was 3 for electrostatic attraction. The energy consumption of the MCDI process is calculated as 0.251 kWh m3and 0.039 kWh g−1Cr at 1.2 V. We envisage that the use of AC@SiO2-NH2electrodes will pave the way for efficient operation of MCDI as well as the preferential recovery of Cr(Ⅲ)-EDTA.

Image-based deformation measurement (IBDM) techniques entail the use of image sequences for extracting metric information to be compared over time. Their applications may concern several domains, such as civil and mechanical engineering as well as geosciences. The rationale behind IBDM and the methodological classification are discussed in the paper along with some examples of application derived from the experience of the authors. The main advantages of IBDM techniques are the non-contact observational capability, the large coverage on the object along with high acquisition rate, as well as an improvement of the degree of image processing automation. In addition, IBDM is generally a relatively low-cost approach. After a short review of the current state of the art, applications are organized into three main categories: (1) photogrammetric coded-target measurements, (2) surface-point tracking to reconstruct dense displacement fields, and (3) comparison of surfaces obtained from dense image matching. Different camera configurations and geometric models to transform points from the image space to the object space are also discussed.