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A simple electrochemical biosensor was developed based on graphitic carbon nitride polymers (g-CN) modified glass carbon electrode (g-CN/GCE). The modified electrode displayed the electrochemical sensitive to dopamine (DA) and showed a good linear and broad response to detect of DA. The inorganic ions had no effect on detecting of DA as well. The decreasing of electrochemical activity was only about 10% after exposure in PBS solution for 15 days which showed excellent stability and reproducibility. It is suggested that the g-CN biosensors have promising application for DA analysis. [ABSTRACT FROM AUTHOR]

The polymeric micelles were prepared by the copolymerization of poly (methoxypolyethylene glycol acrylamide)-macroinitiator (MePEGA) 3-acrylamide phenylboronic acid (APBA) and 2-nitrobenzyl acrylate (NBA) using a surfactant-free miniemulsion reversible addition fragmentation chain transfer (RAFT) polymerization method. The as-prepared micelles were characterized by H NMR, transmission electron microscopy (TEM), and dynamic light scattering (DLS). Due to the UV light and glucose-sensitivity of as-prepared micelles, the micelles could be used to encapsulate insulin. The insulin release properties of micelles under UV light irradiation and different glucose concentrations were investigated. The micelles exhibited relative lower cytotoxicity and excellent stability against protein solution. The loaded insulin remained the structure stability after release through CD spectra analysis. These results showed that the micelles are one of effective candidate carriers for insulin release. [ABSTRACT FROM AUTHOR]

Fluorescent and glucose-sensitive hyperbranched poly(amidoamine)s (HPAMAMs-B) were synthesized via Michael addition of 1-(2-aminoethyl) piperazine, methyl acrylate, and 3-aminobenzeneboronic acid (APBA). These hyperbranched polymers emitted chartreuse photoluminescence and showed emission band at 378 nm under excitation wavelength. The intensity of emission band was enhanced with increasing the amount of APBA in HPAMAMs-B. The glucose sensitivity of HPAMAMs-B has been investigated at different glucose concentrations and pH conditions. These hyperbranched polymers showed potential for biomedical applications such as fluorescence imaging technology and glucose detecting sensors. [ABSTRACT FROM AUTHOR]

Wireless sensor network (WSN) location is a significant research area. In complex environments like forests, inaccurate signal intensity ranging is a major challenge. To address this issue, this paper presents a reliable WSN distance measurement-positioning algorithm for forest environments. The algorithm divides the positioning area into several sub-regions based on the discrete coefficient of the collected signal strength. Then, using the fitting method based on the signal intensity value of each sub-region, the algorithm derives the reference points of the logarithmic distance path loss model and path loss index. Finally, the algorithm locates target nodes using anchor nodes in different regions. Additionally, to enhance the positioning accuracy, weight values are assigned to the positioning result based on the discrete coefficient of the signal intensity in each sub-region. Experimental results demonstrate that the proposed WSN algorithm has high precision in forest environments. [ABSTRACT FROM AUTHOR]

Birds play a vital role in maintaining biodiversity. Accurate identification of bird species is essential for conducting biodiversity surveys. However, fine-grained image recognition of birds encounters challenges due to large within-class differences and small inter-class differences. To solve this problem, our study took a part-based approach, dividing the identification task into two parts: part detection and identification classification. We proposed an improved bird part detection algorithm based on YOLOv5, which can handle partial overlap and complex environmental conditions between part objects. The backbone network incorporates the Res2Net-CBAM module to enhance the receptive fields of each network layer, strengthen the channel characteristics, and improve the sensitivity of the model to important information. Additionally, in order to boost data on features extraction and channel self-regulation, we have integrated CBAM attention mechanisms into the neck. The success rate of our suggested model, according to experimental findings, is 86.6%, 1.2% greater than the accuracy of the original model. Furthermore, when compared with other algorithms, our model's accuracy shows noticeable improvement. These results show how useful the method we suggested is for quickly and precisely recognizing different bird species. [ABSTRACT FROM AUTHOR]

Due to their high surface energy, naked gold nanoparticles (AuNPs) tend to form agglomerates, which could lead to the decrease of active sites and catalytic activity of AuNPs. Herein, the gold nanoparticles/polyacrylonitrile (AuNPs/PAN) nanofibrous membranes have been prepared via an environmentally friendly and efficient route combining electrospinning, amination, and electroless plating technique. The abundant amine and imine groups can be introduced onto the surface of PAN nanofibrous membranes via amination treatment which could be used as 'anchoring sites' to immobilize AuNPs. The resultant composite membranes were applied as the new catalytic materials for reduction of 4-nitrophenol to 4-aminophenol under room temperature. The new catalytic membranes exhibited the significant advantages, such as low dosage, high catalytic activity, easy recycling, and excellent stability. [ABSTRACT FROM AUTHOR]

Freestanding paper-like materials prepared from chemically derived graphene have considerable potential as a carbon-based catalyst in high-performance flexible catalytic reaction. Herein, a highly flexible graphene paper (GP) assembled from graphene oxides (GOs) with the aid of polyacrylamide (PAA) and electroless deposition of gold nanoparticles (AuNPs) was prepared. In contrast to previous reports on GOs based on a flow-directed assembly of graphene sheets, this GOs/PAA/Au composite paper exhibited a highly wrinkled and disordered morphology. The resultant GOs/PAA/Au composite paper was applied as a catalytic material for the reduction of 4-nitrophenol and showed the favour separation, recovery and cyclic utilization properties. [ABSTRACT FROM AUTHOR]

The multi-sensitive micelles were prepared through a photoinitiated polymerization and self-assembly route using 2-ketobutyric acid (2-KBA) as effective water-soluble photoinitiator and emulsifier. The drug release behaviors were investigated under different glucose concentration, pH and temperature conditions. This work provides a new platform for development drug delivery vehicles with reducing possible utilization of organic solvents and initiators and surfactants. [ABSTRACT FROM AUTHOR]

Highlights: [•] Well-defined PMTFPS-b-PMMA diblock copolymers were synthesized. [•] The electrospun PMTFPS-b-PMMA surfaces with low content of PMTFPS could exhibit a superhydrophobic property. [•] The electronspinning conditions would have important effect on the surface morphology, surface composition and wetting behavior of electrospun films. [ABSTRACT FROM AUTHOR]

Aiming at effectively utilizing visible light and convenient separation of the photocatalysts from the water-treatment system, the N + S-codoped BiOBr photocatalysts with a three-dimensional (3D) open porous structure and visible-light photocatalytic performance have been immobilized on the surface glass fibers (GFs) by a facile solvothermal route. The morphologies and structure of the resultant samples were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT). The as-prepared samples exhibited excellent photocatalytic activities for degradation of rhodamine (RhB) under visible light irradiation. More than 98% RhB can be removed after irradiation for 60 min under visible light. Furthermore, this hybrid material can be easy to separate from the water-phase system. This research provides a new route to access a visible-light induced and convenient separation photocatalyst with a high activity under mild conditions. [ABSTRACT FROM AUTHOR]

Abstract: Aiming at effectively utilizing visible light and convenient separation of the photocatalysts from the water treatment system, the N-doped BiOBr photocatalysts with nanosheets structure and visible light photocatalytic properties have been immobilized on the surface of carbon fibers (CFs) by a facile solvothermal route. The morphology and structural properties of the resultant N-doped BiOBr/CFs hybrid structures were investigated by scanning electron microscopy (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The as-prepared N-doped BiOBr/CFs hybrids exhibited excellent photocatalytic activities for the degradation of organic pollutants (rhodamine B and methanol) under visible light irradiation. [Copyright &y& Elsevier]