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Semiconductor materials represent an ideal choice for designing surface‐enhanced Raman scattering (SERS)‐based sensors due to their superior thermal and chemical stability compared to conventional metal materials. However, current SERS‐active semiconductor substrates have limitations such as low detection sensitivity and often complicated preparation steps, which restrict their real‐life applications. In this work, for the first time the feasibility of large‐area fabricating SERS‐active semiconductor substrates based on screen‐printing of micron‐sized TiO2 ink synthesized through a simple flame thermal‐assisted method is demonstrated. The resultant TiO2 microspherical arrays (MSAs) exhibit extraordinary SERS sensitivity with an enhancement factor of 3.28 × 107, which represents one of the highest sensitivity and are the easiest strategy among the reported SERS‐active semiconductor substrates. Both experiments and simulations rationalize the observed enhancement factor and propose that multiple synergistic resonances, including Mie resonance, charge‐transfer resonance, and molecular resonance significantly boost the performance of semiconductor substrates. Dye‐modified TiO2 MSAs are further exploited as the sensing platform for the development of a ratiometric SERS sensor, enabling the highly sensitive, selective, low cost, and stable detection of Hg2+ ions. This study opens up new possibilities for preparing a large‐scale SERS‐active semiconductor array, ultimately advancing the fields of semiconductor‐based SERS sensing technology. [ABSTRACT FROM AUTHOR]

The effect of ultrasound, ozone, and their combination treatment on the removal of two common pesticides (trichlorfon and phoxim) in pak choi samples was studied in this work. The results showed that both ultrasound and ozone treatment alone can significantly remove trichlorfon and phoxim residues in pak choi (>90%), but they reduced the quality of pak choi (such as vitamin C and color). Ultrasound and ozone had a synergistic effect on the removal of pesticide residues in pak choi. The synergistic effect of combined treatment was evaluated from the perspective of pesticide removal speed, and found that their combination significantly accelerated the removal of pesticides. Compared with ultrasound or ozone alone, the removal rate constant of trichlorfon by the combined treatment increased by 121% and 347%, and that of phoxim increased by 159% and 367%, respectively. In addition, the combined treatment of ultrasound and ozone can well maintain the vitamin C and color of pak choi while removing pesticides. Therefore, the combined treatment of ultrasound and ozone can be used as an effective cleaning method to remove pesticide residues in vegetables. Practical applications: Reducing pesticide residues in vegetables is of great significance to human health, and how to maintain the quality of vegetables as much as possible while removing pesticides is a key issue. In this study, the combination of ultrasound and ozone significantly accelerated the removal of pesticides, and retained the vitamin C and color of pak choi well. Therefore, the combined application of ultrasound and ozone has the potential to be an industrial cleaning method for removing pesticide residues in fruits and vegetables without compromising quality. [ABSTRACT FROM AUTHOR]

Designing photodetectors (PDs) with fast response and low power consumption is important for the realization of photoelectric conversion in photoelectric integrated systems. The emerging metal halide perovskite is proven to be a promising material for PD array devices due to its excellent photoelectric performance and large‐area production. However, the array integration of self‐powered perovskite PDs still faces challenges due to the incompatibility between perovskite and micro‐nano processing, hindering practical applications. Here, a perovskite‐compatible device fabrication process is reported for the construction of a perovskite PD array (10 × 10 pixels) with asymmetric contacts, enabling self‐powered photodetection and high‐performance imaging applications. Au and ITO/ZnO electrodes are deposited on the substrate in sequence as the asymmetric contacts. Patterned CH3NH3PbI3 films with uniform and pinhole‐free morphology are then synthesized by a photolithography‐assisted vapor–solution fabrication method as the photosensitive material. The introduction of asymmetric electrodes enables the easy collection of holes at the Au electrode side and electrons at the ITO/ZnO electrode side with light irradiation, resulting in self‐powered photodetection performance. Moreover, the PD array exhibits a uniform distribution of light response and is successfully demonstrated for light imaging. This work opens up a new avenue to develop large‐scale high‐performance perovskite optoelectronic devices with low power consumption. [ABSTRACT FROM AUTHOR]

Optoelectronic synaptic devices integrating light‐perception and signal‐storage functions hold great potential in neuromorphic computing for visual information processing, as well as complex brain‐like learning, memorizing, and reasoning. Herein, the successful growth of MoS2 monolayer arrays assisted by gold nanorods guided precursor nucleation is demonstrated. Optical, spectral, and morphology characterizations of MoS2 prove that arrayed flakes are homogeneous monolayers, and they are further fabricated as optoelectronic devices showing featured photocurrent loops and stable optical responses. Typical synaptic behaviors of photo‐induced short‐term potentiation, long‐term potentiation, and paired pulse facilitation are recorded under different light stimulations of 450, 532, and 633 nm lasers at various excitation powers. A visual sensing system consisting of 5 × 6 pixels is constructed to simulate the light‐sensing image mapped by forgetting curves in real time. Moreover, the system presents the ability of utilizing associated images to restore vague and incomplete memories, which successfully mimics human intelligent behaviors of association memory and logical reasoning. The work emulates the brain‐like artificial intelligence using arrayed 2D semiconductors, which paves an avenue to achieve smart retina and complex brain‐like system. [ABSTRACT FROM AUTHOR]

BACKGROUND: Ultrasound has the potential to increase microbial metabolic activity, so this study explored the stimulatory effect of ultrasound pre‐treatment on the degradation of four common pesticides (fenitrothion, chlorpyrifos, profenofos, and dimethoate) during milk fermentation by Lactobacillus plantarum and its effect on yogurt quality. RESULTS: Appropriate ultrasound pretreatment significantly enhanced the growth of L. plantarum. The degradation percentages of pesticides increased by 19–38% under ultrasound treatment. Ultrasonic intensity, pulse duty cycle, and duration time were key factors affecting microbial growth and pesticide degradation. Under optimal ultrasonic pre‐treatment conditions, the degradation rate constants of four pesticides were at least 3.4 times higher than those without sonication. In addition, such ultrasound pretreatment significantly shortened yogurt fermentation time, increased the water holding capacity, hardness and antioxidant activity of the yogurt, and improved the flavor quality of the yogurt. CONCLUSION: Ultrasonic pretreatment significantly accelerated the degradation of the four pesticides during yogurt fermentation. In addition, such ultrasound pretreatment increased the efficiency of yogurt making and improved the quality of yogurt in terms of water holding capacity, firmness, antioxidant activity, and flavor. These findings provide a basis for the application of ultrasound to the removal of pesticide residues and quality improvement of yogurt. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Drying is an important and influential process to prolong the shelf‐life of food in the food industry. Recent studies have shown that cold plasma (CP) as an emerging drying pretreatment technology can improve drying performance, reduce drying energy consumption, and improve dried food quality. This paper comprehensively reviewed the mechanism of CP improving drying performance, related equipment, energy consumption, influencing factors, and impact on drying quality. This review also discusses the advantages and disadvantages and proposes possible challenges and suggestions for future research. Most studies indicated that CP pretreatment could improve the drying rate and quality and reduce the drying energy consumption. CP can promote moisture diffusion and improve drying efficiency by etching the surface and affecting the internal microstructure. In addition, CP can enhance the quality of dried products by reducing drying time and enzyme activity. Further research is needed to explore the drying mechanisms and equipment innovations to promote the application of CP in the food drying industry. [ABSTRACT FROM AUTHOR]

Low‐dimensional perovskite structures are ideal materials for nano/microlasers owing to their excellent optical gain properties and high emission efficiency. But it is still a challenge to achieve single‐mode and tunable lasing behaviors in micro‐scale perovskite, especially showing ultralow thresholds in tens of µJ cm−2. In this work, CsPbBr3/Ag hemispheroids have been synthesized in a designed chemical vapor deposition (CVD) process. Benefiting from the whispering gallery resonance mode and plasmon‐enhanced light–matter interactions in well‐confined hybrid cavities, the CsPbBr3/Ag plasmonic microlasers exhibit low pump thresholds down to 35–51 µJ cm−2. Interestingly, single‐mode and two‐mode lasing behaviors are determined by the morphology of plasmonic Ag nanostructures, and lasing modes could be selectively tuned by increasing the pump fluence accompanying with dynamic competitions of photonic and plasmonic modes. Simulations of electromagnetic field have been plotted to show near‐field resonant modes for a comprehensive understanding of plasmon‐assisted lasing. These results not only provide a solution to fabricate low‐threshold plasmonic microlasers, but also advocate the prospect of all‐inorganic perovskite nanostructures as promising candidates for on‐chip integrated light sources. [ABSTRACT FROM AUTHOR]

Knowledge of protein properties is vital for quality assessment in meat systems. This study applied Raman spectroscopy to investigate the relationship between protein oxidation/denaturation and conformational changes in beef during repeated freeze–thaw (RFT). A lower α‐helix and higher β‐sheet content was observed after RFT. The I850 cm−1/I830 cm−1 intensity ratio of tyrosine indicates that tyrosine residues were exposed to the polar environment during RFT. Further, RFT led to increased carbonyl content and surface hydrophobicity, with decreased total sulphydryl content, Ca2+‐ATPase activity and enthalpy of myosin (ΔH1). Subsequently, correlation analysis showed that carbonyl content, Ca2+‐ATPase activity and ΔH1 in beef protein have good correlations with secondary protein structure data, especially ΔH1, which has a strong negative correlation (r = −0.906) with the β‐sheet/α‐helix ratio. Therefore, protein secondary conformation information during RFT has the potential to be used as a parameter for studying the thermal properties of myosin. [ABSTRACT FROM AUTHOR]

BACKGROUND Aroma scalping is a very common problem and can affect the sensory quality of packaged food. To study the aroma scalping characteristics of polyethylene terephthalate laminated steel (PET‐LS), the sorption kinetics of six common aroma compounds (2‐pentanone, 2‐heptanone, hexanal, citral, butyl acetate, isopentyl acetate) in foods were assessed for drawn–redrawn cans made with PET‐LS. RESULTS: Storage temperature and initial concentration were proved as important factors to affect compound sorption and diffusion for flavors. The correlation between logarithm of equilibrium absorption ln M∞ and reciprocal of absolute temperature 1/T showed good linear relationship (R2 = 0.9380–0.9998) at 4 °C, 20 °C and 50 °C, and the M∞ obtained by the experiment was very close to the predicted value at 37 °C. At low initial concentration (below 500 µL L−1), the absorption capacity and initial concentration showed a slow linear growth trend, whereas there was a rapid change at high initial concentration. The values of diffusion coefficient D were on the order of 10−11–10−12 m2 day−1, which were lower than reported for other polymer materials (linear low‐density polyethylene, polybutylene succinate, polylactic acid). CONCLUSION: The equilibrium absorption amount of each flavor component was dependent on the temperature under the same concentration (500 µL L−1). The Fickian diffusion model was used for fitting the experimental kinetics values satisfactorily (R2 = 0.9158–0.9885). © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In this study, a novel hybrid molecularly imprinted polymer (MIP) with a surface-enhanced Raman spectroscopy (SERS) sensor was proposed for the detection of chloramphenicol in milk. The MIP was prepared by precipitation polymerization, and the template molecule was extracted by ultrasonic wave. The polymer was placed in a sodium citrate reduction reaction to prepare the chloramphenicol-MIP-Au substrate. The optimal detection conditions were carried out in a mixed solution of methanol and water (1:9). The sensor can be used to detect chloramphenicol in milk samples with a detection limit of 0.1 µg/ml. The chloramphenicol-MIP-Au substrate served not only as an enrichment medium but also as an enhancement substrate base for SERS detection. Experimental results showed that the MIP hybrid as a SERS platform owned potential for simplifying the detection step and highly selective detection of chloramphenicol in milk. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

BACKGROUND The aim of this research was to understand the migration of bisphenols from can coatings into foods in the Chinese market. RESULTS The migration of bisphenols was studied in commercial cans from the Chinese market filled with four types of food simulant (FS), which were heated at 121 °C for 30 min and stored at 40 °C for 30 days. Only bisphenol A (BPA) and bisphenol A diglycidyl ether (BADGE) were found in the can coatings, and SimC (10% (v/v) ethanol/water) was the most suitable FS for their release. The levels of these bisphenols in 24 kinds of canned beer from Chinese markets were also investigated. The average concentrations of BPA and BADGE were 2.85 ± 0.79 and 0.38 ± 0.19 µg · L−1 respectively, which were both lower than the EU limits, and their respective daily intakes were estimated at 0.015 and 0.0020 µg · kg−1 body weight · day−1. Besides, increasing storage temperature and time accelerated the release of bisphenols into FSs. CONCLUSION The present results provide some guidance to reduce the migration of bisphenols during the transport and storage of canned foods. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Mycotoxin contamination of food has been gaining increasing attention. Hidden mycotoxins that interact with biological macromolecules in food could make the detection of mycotoxins less accurate, potentially leading to the underestimation of the total exposure risk. Interactions of the mycotoxins alternariol (AOH) and alternariol monomethyl ether (AME) with high‐molecular glutenin were explored in this study.The recovery rates of AOH and AME (1, 2, and 10 μg kg−1) in three types of grains (rice, corn, and wheat) were relatively low. Molecular dynamics (MD) simulations indicated that AOH and AME bound to glutenin spontaneously. Hydrogen bonds and π‐π stacking were the primary interaction forces at the binding sites. Alternariol with one additional hydroxyl group exhibited stronger binding affinity to glutenin than AME when analyzing average local ionization energy. The average interaction energy between AOH and glutenin was −80.68 KJ mol−1, whereas that of AME was −67.11 KJ mol−1.This study revealed the mechanisms of the interactions between AOH (or AME) and high‐molecular glutenin using MD and molecular docking. This could be useful in the development of effective methods to detect pollution levels. These results could also play an important role in the evaluation of the toxicological properties of bound altertoxins. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]