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Sustainable development based on the value-added utilization of furfural residues (FRs) is an effective way to achieve a profitable circular economy. This comprehensive work highlights the potential of FRs as precursor to prepare porous carbons for high performance supercapacitors (SCs). To improve the electrochemical performance of FR-based carbon materials, a facile route based on methanol pretreatment coupled with pre-carbonization and followed KOH activation is proposed. More defects could be obtained after methanol treatment, which is incline to optimize textural structure. The activated methanol treated FR-based carbon materials (AFRMs) possess high specific surface area (1753.5 m2 g−1), large pore volume (0.85 cm3 g−1), interconnected micro/mesoporous structure, which endow the AFRMs with good electrochemical performance in half-cell (326.1 F g−1 at 0.1 A g−1, 189.4 F g−1 at 50 A g−1 in 6 M KOH). The constructed symmetric SCs based on KOH, KOH–K3Fe(CN)6 and KOH-KI electrolyte deliver energy density up to 8.9, 9.9 and 10.6 Wh kg−1 with a capacitance retention of over 86% after 10,000 cycles. Furthermore, the self-discharge can be restrained by the addition of K3Fe(CN)6 and KI in KOH electrolyte. This study provides an effective approach for high-valued utilization of FR waste.

In this study, Ba4RCo0.5Nb9.5O30 (R = La, Nd, Sm, Eu) (BRCN) ceramics were synthesized using a high-temperature solid-state reaction. The XRD refinement results show that ceramic samples are tetragonal tungsten bronze (TTB). As the radius of rare-earth ions decreases, the unit cell volume of BRCN ceramics decreases, and the radius difference between Ba2+ and R ions increase, which results in BO6 octahedral distortion and the Raman peaks shift to high frequency. In addition, as the radius of rare-earth ions decreases, the ionic displacements increase and thus the dielectric constant peak temperature goes up. The high-temperature impedance results show that there exists n-type electronic conduction in the samples. The remanent polarization of the P–E curve at low frequencies increases from 0.470 to 1.038 μC cm−2 as the rare-earth ion radius decreases.

The triboelectric effect has recently demonstrated its great potential in environmental remediation and even new energy applications for triggering a number of catalytic reactions by utilizing trivial mechanical energy. In this study, Ba4Nd2Fe2Nb8O30 (BNFN) submicron powders were used to degrade organic dyes via the tribocatalytic effect. Under the frictional excitation of three PTFE stirring rods in a 5 mg/L RhB dye solution, BNFN demonstrates a high tribocatalytic degradation efficiency of 97% in 2 h. Hydroxyl radicals (•OH) and superoxide radicals (•O2－) were also detected during the catalysis process, which proves that triboelectric energy stimulates BNFN to generate electron-hole pairs. The tribocatalysis of tungsten bronze BNFN submicron powders provides a novel and efficient method for the degradation of wastewater dye by utilizing trivial mechanical energy.

Searching for a new approach in environmental remediation in terms of dye degradation is important in industrialized society. In this work, ferroelectric Ba2.5Sr2.5Nb8Ta2O30 (BSNT) submicron powders prepared by the high-temperature solid-phase method are used for dye degradation under magnetic stirring. The dye in solution can be quickly degraded by magnetically stirring BSNT submicron particles in the dark in ambient temperature conditions. More importantly, the degradation efficiency can be greatly improved through simple modification of the stirring materials from glass to polypropylene, with a degradation efficiency of rhodamine B as high as 99% in 1.5 h at a gentle stirring speed of 300 rpm. Control experiments reveal that the degradation of the dye is mainly contributed by the friction between BSNT submicron particles and PTFE stirring rods. It is proposed that the friction between ferroelectric polar BSNT particles and PTFE causes charge transfer and induces a non-zero internal electric field to drive the separation of electron–hole pairs in BSNT particles, resulting in a novel tribocatalytic degradation of the dye, which is proven by the detection of ˙OH and ˙O2− intermediate products during stirring. This work demonstrates that the friction energy of ferroelectric materials with strong polarization is an alternative approach for highly efficient dye degradation.

Vehicle detection plays a vital role in vehicle assisted driving. Aiming at the low accuracy and missed detection problems of SSD algorithm for vehicle detection, an improved SSD algorithm is proposed. In order to extract more vehicle feature information, we propose a SSD network with ResNet50 as the backbone. Aiming at the problem of low recognition rate of small target vehicles, the Feature Fusion Model was designed by fusing the position information of shallow features with the semantic information of deep features; in order to improve the performance of the model, we inserted SE block in the feature extraction layer to analyze different features. The importance of the channel is recalibrated. The experimental results show that the improved method has an average accuracy of 83.09% on the self-made vehicle data set, which is 3.23% higher than the accuracy of the previous algorithm.

A polyaniline-modified immunosensor which integrated the immuno-chromatography assays with the four-wire electrode impedance spectroscopy scanning was developed for E. coli O157:H7 detection. Aniline doped with polystyrene sulfonic acid (PSSA) was used to synthesize the soluble polyaniline (PANI). The Fourier UV - Vis spectroscopy and scanning electron microscope (SEM) technology were applied to characterize the property of polyaniline. In order to reduce the interfacial effects of biosensor effectively, a four-wire interdigitated microelectrode (IME) which allowed for conducting four-wire test mode as well as two-wire test mode impedance spectroscopy was introduced. A simplified equivalent circuit of the four-electrode transducer was designed for modeling the performance of the immunosensor. The antigen-antibody interactions with two-wire electrode and four-wire electrode measurements were analyzed to establish whether the four-wire electrode test mode could reduce the impedance which was induced by interfacial effects effectively. The results showed that the soluble polyaniline synthesized by polystyrene sulfonic acid doped (PSSA/PANI) increased the conductivity of the immunosensor. The measurement of the four-wire electrode test mode can be more reliably to measure of the biologically specific interaction by decreasing the impedance of interfacial effects. The impedance of bacteria solutions was lower than that of blank. And the impedance value was inversely proportional to the concentration of the bacteria. A linear relationship between the impedance variation and logarithmic value of the cell concentration was found from 1.15 × 103 CFU/mL to 1.15 × 107 CFU/mL in pure culture. The label-free impedance biosensor was able to detect as low as 1 × 103 CFU/mL in pure culture.

A new analytical method was developed to determine total purine content in fish meat. The analysis principle is that total purine extracted from fish meat are turned into uric acid by diazotization reaction and xanthine oxidase reaction. Then, the content of uric acid is measured by surface-enhanced Raman spectroscopy (SERS). The results showed that the optimal conditions for the diazotization reaction were at 60 °C for 40 min, using 0.16 M HCl, and 3.00 g/L NaNO2. The optimal xanthine oxidase reaction conditions were using 100 U/L xanthine oxidase, conducting at 30 °C and pH 7.0 for 40 min. The calibration curve established at the characteristic Raman peak of 631 cm−1 had a good linear relationship (R2 = 0.9864). The recovery rate was between 101.7% and 105.0%. Therefore, the total purine content in the fish meat can be quantitatively determined with this new method.

Study on the dielectric phenomena of cells is critical to the further understanding of electromagnetic effect on cells. The dielectric properties of Bacillus cereus spores were measured for frequencies ranging from 500 to 8500 MHz using coaxial-line probe technology. The influence of Bacillus cereus spores concentration on the dielectric spectroscopy was explored at microwave frequency region. The results showed that the dielectric constant of the sample with Bacillus cereus spores and blank decreased with increasing frequency, especially at higher frequencies. The loss factor had a minimum of about 3420 MHz. What is more, when the frequency was lower than 3420 MHz, the dielectric constant of Bacillus cereus spores was lower than that of blank. While the loss factor and loss tangent were higher than that of blank. There was a more significant change for the loss factor than the dielectric constant between the Bacillus cereus spores and blank. Thus, the dielectric constant can be an indicator in Bacillus cereus spores qualitative analysis.