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In order to improve the effect of the gas extraction, to explore the transformation characteristics of freezing and thawing cycle of coal pore, vacuum full anthracite coal samples of water are placed in cooler（-20 ℃）, the nuclear magnetic resonance T2 spectrum was used to analyze the cracking effect of different freezing -thawing cycles, and the pore structure changes of coal samples before and after freezing-thawing were studied. The results showed that the T2 spectrum area increased greatly during the first to third freeze -thaw cycles, and reached the maximum value of 42.41% in the third freeze -thaw cycle. The increase of T2 spectrum area of 4 to 9 freeze -thaw cycles decreases continuously, and the cracking effect of freeze -thaw cycles decreases continuously. In the process of the third freeze -thaw cycle, the change of pore structure is the largest, and the comprehensive analysis shows that the third freeze-thaw cycle is the best number of freeze-thaw cycles.

The current study investigated the impact of germination duration on the functional components (vitamin C, γ-aminobutyric acid (GABA), polyphenols, flavonoids) and antioxidant activity of germs and cotyledons of the germinated Chinese chestnut (Castanea mollissima). We utilized seeds of the "Zaofeng" Chinese chestnut to germinate, and sowed the seeds in wet sand at 22 °C and 85% relative humidity. The germination rate, length, diameter, and fresh weight of the sprouts were investigated at 0, 2, 4, 6, 8, and 10 days after sowing, and the kinetic changes of amylose, amylopectin, sugar components, soluble protein, vitamin C, GABA, total phenols, flavonoids, and the DPPH and ABTS free radical scavenging activity in the germs and cotyledons were monitored, respectively. The findings revealed that the germination rate and germ biomass increased continuously during germination. The germination rate reached 90% on the 8th day after sowing. Germination reduced amylose in cotyledons from 42.3% to 34.2%, amylopectin from 42.9% to 25.8%, total sugar from 12.6% to 11.4%, and vitamin C from 1.45 mg/g to 0.77 mg/g. Meanwhile, soluble protein in the embryos rose from 0.31% to 0.60%, vitamin C from 21.1 to 29.4 mg/g, GABA from 0.49 to 1.68 mg/g, total flavonoids from 53.6 to 129.7 mg/g, and ABTS antioxidant activity from 1.52 to 3.27 μmol TE/g. The average contents of D-fructose, inositol, vitamin C, GABA, polyphenols, and flavonoids and the DPPH and ABTS antioxidant activity in germs were as high as 22.5, 6, 35, 7.5, 10, 20, and 10 and 20-fold those of cotyledons, respectively. Especially, the average content of glucose in germ was as high as 80-fold that of cotyledon. D-xylulose, D-galacturonic acid, and D-ribose were only found in germs, but not in cotyledons. Considering the germ biomass and functional components content, germs of Chinese chestnuts germinated at 22 °C for 8 days are considered the most suitable raw material for functional food products. In conclusion, controlled germination not only enhances the physicochemical and functional properties of Chinese chestnut germs but also reduces the caloric content and improves the nutritional composition of the cotyledons appropriately. Moreover, the comprehensive evaluation of compositional changes and functionality in the embryo and cotyledon of Chinese chestnuts will provide a solid foundation for subsequent functional food processing utilizing germinated Chinese chestnuts. [ABSTRACT FROM AUTHOR]

Summary: Senescence accompanying browning is the main factor that reduces the sensory and nutritional quality of cherries during storage. In the present study, we analysed the effects of sodium nitroprusside (SNP) treatment with 0, 200, 400, and 600 μm on delaying the senescence and browning of cherries preserved at 4 °C for 30 days. Results suggested that 400 μm SNP treatment significantly enhanced the antioxidant capacity and maintained better fruit quality. Specifically, SNP treatment inhibited the activity of polyphenol oxidase, delayed the browning of cherry flesh and reduced soluble quinone content. Meanwhile, the peroxidase (POD), catalase and phenylalanine ammonia‐lyase (PAL) activities were enhanced by SNP treatments, while reactive oxygen species accumulation and membrane lipid peroxidation were alleviated. In addition, SNP treatment increased the accumulation of phenols, flavonoids and anthocyanins, which also enhanced the 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) scavenging capacity in cherries. Therefore, our results support SNP treatment to be a potential approach to delay flesh browning and maintain the sensory and nutritional qualities of cherries. [ABSTRACT FROM AUTHOR]

Sulfur dioxide (SO2) fumigation has been widely used to control pathogens and maintain the postharvest quality of table grapes. However, the effective dosage of SO2 treatment is close to causing bleaching damage on fruits. Further, the SO2 potential residue is a risk to human health. In this study, the dominant pathogens in "red globe" grapes during cold storage (0 and 10°C) were identified as Botrytis cinerea, Alternaria alternata, and Penicillium expansum, while Aspergillus niger was dominant pathogen when the grapes were stored at room temperature (25°C). The isolated dominant pathogens were effectively suppressed by SO2 ranging from 500 μl L−1 to 800 μl L−1, but bleaching spots were observed in grapes when SO2 was applied at 800 μl L−1. To reduce the SO2 residue, the fungicides dimethomorph and thiophanate‐methyl were respectively sprayed to control the epiphytic pathogens during the development of grape berries. In addition, the reduced microbial population contributed by fungicide treatments remitted the original density of postharvest microbial growth. The postharvest automated intermittent SO2 fumigation at 500 μl L−1 was subsequently integrated to control the microbial activities. In addition, SO2 maintained the soluble solid content and titratable acid content, which were 22% and 75% higher than the control (p <.05) on 120 days of storage. The inhibition percentage against dominant fungal pathogens by preharvest fungicides spray was approximately 30%, while the postharvest intermittent SO2 fumigation contributed about 50%. We investigated the suppression role of preharvest and postharvest combined treatment for the grapes, which was concluded as a promising application to reduce decay and extend the shelf life of "red globe" grapes. [ABSTRACT FROM AUTHOR]

Organic semiconductor devices with low energy consumption and excellent stability are highly desirable. Controlling the intermolecular alignment orientation by designing the molecular structure or optimization of the film preparation process is an alternative way to achieve this goal. In this paper, a new idea was proposed to realize the formation of an aligned monomolecular layer and multimolecular layer thin films on the electrode substrate by controlling the surface pressure of molecular layer on the liquid surface by LB technology. An amphiphilic π‐conjugated D−A molecule was synthesized, and the influence of spin coating and LB technology on intermolecular ordered stacking in the film and the electrical memory performance were investigated. The results demonstrated that the film fabricated by LB technology has some advantages compared with that fabricated by spin‐coating method, such as higher crystallinity, lower surface roughness and better‐organized monomolecular and multimolecular layer, which significantly promoted the performance of the electrical memory device with lower power consumption and longer stability. [ABSTRACT FROM AUTHOR]