Search

In order to give the boiled sunflower seeds the rich taste, caramel aroma, and improved oxidation resistance, Maillard peptides were added to sunflower seeds in this research. Sunflower seeds sample 5 (SFS5) and sunflower seeds sample 2 (SFS2) were prepared by adding Maillard peptides of sunflower seeds (K), gluten (G), and corn (Y), at different ratio (SFS2, K:G = 8:2; SFS5, K:G:Y = 8:1:1). Component analysis showed that SFS5 and SFS2 were significantly higher in umami amino acids than the control (SFS0) without Maillard peptides. SFS5 and SFS2 contained more hybrid compounds such as pyrazines and furans which contributed to the caramel aroma of sunflower seeds. Electronic tongue analysis revealed the higher response values of umami, salty, and continuity taste for SFS5 and SFS2 than those of SFS0. Sensory evaluation results showed that the sunflower flavor, caramel aroma, umami characteristic, and overall acceptability of SFS5 and SFS2 were higher than that of SFS0. The chemical results showed that under accelerated oxidation, the SFS5 and SFS2 had significantly lower peroxide value and acid value than SFS0. [ABSTRACT FROM AUTHOR]

This paper aims to research the air leakage of coal goaf near to thin band in Nantun Coal Mine. With using PFC3D numerical simulation software and establishing close distance coal seams mining numerical model, it analyzes roof migration characteristics of lower coal seam during mining and researches the law of development of roof air leakage passage in goaf; It also analyzes the changing situation of porosity of goaf in upper coal seam and researches the law of leaking oxygen expansion of goaf in upper coal seam. It is indicated from the research results that the curve and subsidence of main roof on working face forms fractures and cracks in its interior causing the air leakage passage between upper coal seam and lower coal seam. With the fracture of lower coal seam roof, the range of air leakage passage of goaf expands rapidly. And with the periodic fracture of roof, the air leakage passage moves forward continuously to prompt the leaking oxygen of lower coal seam to go into the upper coal seam goaf, and this is good for the spontaneous combustion of remaining coal body. Before the first weighting of main roof, the porosity of No. 3 upper coal seam goaf almost has no change; during the period of the first weighting of main roof, the porosity in No. 3 upper coal seam goaf close to palisades becomes big; with the periodic caving, the porosity of No. 3 upper coal seam goaf appears periodic enlargement and movement, and this is good for the diffusion of leaking oxygen in upper coal seam goaf and intensifies the spontaneous combustion of remaining coal in upper coal seam goaf. [ABSTRACT FROM AUTHOR]

Accurate estimation of high-resolution satellite precipitation products like Global Precipitation Measurement (GPM) and Tropical Rainfall Measuring Mission (TRMM) is critical for hydrological and meteorological research, providing a benchmark for the continued development and future improvement of these products. This study aims to comprehensively evaluate the Integrated Multi-Satellite Retrievals for GPM (IMERG) and TRMM 3B42V7 products at multiple temporal scales from 1 January 2015 to 31 December 2017 over the Huang-Huai-Hai Plain in China, using daily precipitation data from 59 meteorological stations. Three commonly used statistical metrics (CC, RB, and RMSE) are adopted to quantitatively verify the accuracy of two satellite precipitation products. The assessment also takes into account the precipitation detection capability (POD, FAR, CSI, and ACC) and frequency of different precipitation intensities. The results show that the IMERG and 3B42V7 present strong correlation with meteorological stations observations at annual and monthly scales (CC > 0.90), whereas moderate at the daily scale (CC = 0.76 and 0.69 for IMERG and 3B42V7, respectively). The spatial variability of the annual and seasonal precipitation is well captured by these two satellite products. And spatial patterns of precipitation gradually decrease from south to north over the Huang-Huai-Hai Plain. Both IMERG and 3B42V7 products overestimate precipitation compared with the station observations, of which 3B42V7 has a lower degree of overestimation. Relative to the IMERG, annual precipitation estimates from 3B42V7 show lower RMSE (118.96 mm and 142.67 mm, respectively), but opposite at the daily, monthly, and seasonal scales. IMERG has a better precipitation detection capability than 3B42V7 (POD = 0.83 and 0.67, respectively), especially when detecting trace and solid precipitation. The two precipitation products tend to overestimate moderate (2–10 mm/d) and heavy (10–50 mm/d) precipitation events, but underestimate violent (>50 mm/d) precipitation events. The IMERG is not found capable to detecting precipitation events of different frequencies more precisely. In general, the accuracy of IMERG is better than 3B42V7 product in the Huang-Huai-Hai Plain. The IMERG satellite precipitation product with higher temporal and spatial resolutions can be regarded a reliable data sources in studying hydrological and climatic research. [ABSTRACT FROM AUTHOR]