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Based on Raman scattering phenomenon, surface-enhanced Raman spectroscopy （SERS） detection technology enhances "fingerprint" information of tested substance by adsorbing it on the surface of SERS substrate to achieve trace detection. With the advantages of simple pre-processing, high sensitivity, simple operation, real-time non-destructive detection on site and so on, SERS analysis technology has attracted much attention in food safety rapid detection. The characteristics and limitations of various types of SERS substrates were introduced. The recent research on SERS detection technology in food safety detection was summarized in detail. Finally, this paper discussed the challenges of its commercial application, and prospected the future development.

Mytilaria laosensis, a common fast-growing tree species in southern China, boasts excellent growth speed and attractive color and texture. However, due to its short growth cycle and high proportion of juvenile wood, it typically exhibits poor dimensional stability and low strength, which significantly limits its practical applications. This study uses vacuum impregnation to modify M. laosensis wood with polyethylene glycol (PEG), focusing on the effects and mechanisms of PEG with different molecular weights on wood properties. The results indicate that PEG enters the wood cell walls through capillary action and diffusion, forming hydrogen bonds with the free hydroxyl groups on cellulose and hemicellulose, which keeps the cell walls swollen and enhances dimensional stability. Post modification, the dimensional stability of M. laosensis wood improved, with an anti-swelling efficiency ranging from 61.43% to 71.22%, showing an initial increase followed by a decrease with increasing PEG molecular weight. The optimal PEG molecular weight for anti-swelling efficiency was 1500 Da, achieving 71.22%. The flexural modulus of elasticity and flexural strength of the treated wood also first decreased and then increased with increasing PEG molecular weight. Among them, the PEG1000-treated material showed the best performance, with the flexural modulus of elasticity increased by about 29% and the flexural strength increased by about 5% compared to untreated wood. Additionally, PEG, having a higher pyrolysis temperature than wood, raised the initial pyrolysis temperature and maximum pyrolysis rate temperature of M. laosensis wood, thus improving its thermal stability. These findings provide scientific evidence and technical support for the efficient utilization and industrialization of M. laosensis wood, promoting its widespread application and industrial development. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) urea splitting is of great significance for urea wastewater remediation and hydrogen production with low energy consumption simultaneously. Nickel hydroxides as electrocatalysts have been widely investigated for urea electrolysis. However, it is an open question how to synthesize highly catalytic Ni(OH)2 for the PEC urea splitting. Herein, we take advantage of the instability of metal–organic frameworks (MOFs) to perform an in situ synthesis of Ni(OH)2 catalysts on the surface of TiO2 nanorod arrays. This transformed Ni(OH)2 (T-Ni(OH)2) possesses a superior PEC catalytic activity for water/urea splitting in comparison to the Ni(OH)2 prepared by the impregnation method. The in situ transition of a Ni-MOF is accomplished through an electrochemical treatment under AM1.5G illumination in a KOH-and-urea mixed electrolyte. The specific transition mechanism of Ni-MOFs is the substitution of ligands with OH− in a 1 M KOH electrolyte and the successive phase transition. The T-Ni(OH)2@TiO2 photoanode delivers a high photocurrent density of 1.22 mA cm−2 at 1.23 VRHE, which is 4.7 times that of Ni(OH)2@TiO2 prepared with the impregnation method. The onset potential of T-Ni(OH)2@TiO2 is negatively shifted by 118 mV in comparison to TiO2. Moreover, the decline of photocurrent during the continuous test can be recovered after the electrochemical and light treatments. [ABSTRACT FROM AUTHOR]

Polymer plastic is the main component of current outdoor packaging film materials that are mostly derived from fossil fuels. Its poor ultraviolet (UV) barrier performance and short service life caused by aging degradation result in increased non‐renewable consumption and environmental pollution. The most effective way to solve these problems is the development of a biomass‐based and eco‐friendly packaging with excellent UV‐blocking performance. Herein, inspired by mussels, a facile strategy is reported for the preparation of a biomimetic polymeric material via the incorporation of a biomass‐derived catechol derivative Acacia mangium tannin (AMT) into a biodegradable soy protein isolate (SPI) matrix. The morphologies, mechanical, thermal properties, and UV‐blocking abilities and mechanisms of the modified films were evaluated. With the increase of the AMT content, the stress of the composite film was found to gradually increase, and the modified SPI composite film exhibited a powerful tensile strength of 7.64 MPa and a high breaking strain of 145.6%. After the introduction of AMT, the films exhibited excellent UV‐blocking performance. As both SPI and AMT are biodegradable, this work presents an innovative design strategy for fully‐biodegradable and robust polymeric materials with excellent UV‐blocking performance that have promising potential applications in packaging. [ABSTRACT FROM AUTHOR]

Pseudocapacitance is mainly contributed by fast surface‐controlled reactions. However, the effect of nanostructures on the capacitive behaviour has not been systematically studied yet. In this work, we synthesize different Co3O4 nanostructures with the same crystal structure and exposed clean crystal planes that include 1D nanowire, 2D nanosheet, 3D rambutan‐like and hierarchical structures, ranging from low to high dimensions. It is discovered the specific capacitance of Co3O4 materials follows the order of 1D nanowire > hierarchical structure > 2D nanosheet > 3D rambutan‐like structure while the electron transfer resistance is 1D nanowire < 2D nanosheet < hierarchical structure < 3D rambutan‐like structure. Under the same electrochemistry, results suggest the pseudocapacitance is not simply dependent on the surface area offered by the nanostructure, but relies on the conductivity, accessibility, diffusion rate and reactivity of the electrode. 1D nanostructure can render the highest reactant accessibility, fastest electron transfer and largest diffusion rate, thus achieving the highest specific pseudocapacitance. [ABSTRACT FROM AUTHOR]

Phenolic foam composites (PFs) are of substantial interest due to their uniform closed-cell structure, low thermal conductivity, and good thermal insulation performance. However, their disadvantages of a high pulverization rate and poor mechanical properties restrict their application in building exterior insulation. Therefore, the toughening of these composites is necessary. In this paper, poplar fiber was treated with an acetylation reagent, and the acetylated fiber was used to prepare modified phenolic foams (FTPFs); this successfully solved the phenomenon of the destruction of the foam structure due to the agglomeration of poplar fiber in the resin substrate. The foam composites were comprehensively evaluated via the characterization of their chemical structures, surface morphologies, mechanical properties, thermal conductivities, and flame retardant properties. It was found that the compressive strength and compressive modulus of FTPF-5% respectively increased by 28.5% and 37.9% as compared with those of PF. The pulverization ratio was reduced by 32.3%, and the thermal insulation performance and flame retardant performance (LOI) were improved. Compared with other toughening methods for phenolic foam composites, the phenolic foam composites modified with surface-compatibilized poplar fiber offer a novel strategy for the value-added utilization of woody fiber, and improve the toughness and industrial viability of phenolic foam. [ABSTRACT FROM AUTHOR]

Elevated BMI is a known risk factor for metabolic syndrome (MS). Few studies have examined the joint association of BMI and body composition with the risk of MS. Our study investigated individual thresholds of BMI and body composition for an increased risk of MS and the joint association of BMI and body composition with the risk of MS in Chinese women. This is a cross-sectional analysis of 3,734 rural Chinese women aged 20-39 years. Body composition was assessed by DEXA, including measures of percent body fat (%BF) and proportion of trunk fat to total body fat (%TF). Graphic plots were used to explore BMI, %BF and %TF thresholds for increased prevalence of MS. Logistic regression models were used to examine the individual and joint association of BMI, %BF, and %TF with the risk of MS. When examined individually, an increased risk of MS was noted at BMI >= 24 kg/m[sup 2]; %BF>=32; and %TF>=53, respectively. Prevalence of MS was low (ranging from 0% to 2.2%) for individuals with a BMI<24 kg/m[sup 2], and increased to 7.1% with a BMI >= 24 kg/m[sup 2] (24.0-24.9 kg/m[sup 2]). Similar patterns were observed for low vs. high %BF (<32 vs. >=32) and %TF (<53 vs. >=-53). When examined jointly, among women with BMI<24 and using women with a %BF<32 and %TF<53 as a reference, women with a %TF >=53 alone had a 4.6-fold higher risk of MS (%95 CI 1.8-12.0), women with a %BF >= 32 alone had a 3.8-fold higher risk of MS (95% CI 0.4-31.7); a similar pattern was observed among women with BMI>=24, and the highest risk was observed among women with %BF>=32 and %TF>=53 (OR=77.6, 95%CI 36.5-164.9). Our results suggest that in this Chinese population, a BMI >=24 cut-off was associated with markedly increased risk of MS and that independent of BMI, high %BF and high %TF each contributed to the increased risk of MS. [ABSTRACT FROM AUTHOR]