The principles of fracture development during underwater blasting are examined based on explosion and impact dynamics,fluid dynamics,fracture dynamics,and field testing.The research reveals that the fracturing of the ...The principles of fracture development during underwater blasting are examined based on explosion and impact dynamics,fluid dynamics,fracture dynamics,and field testing.The research reveals that the fracturing of the surrounding rock during underwater blasting is due to the combined action of shock and stress waves for the initial rock breakage and subsequent water expansion.The fracture development model for the surrounding rock of a drilling hole during underwater blasting is established.The rock fracturing range under the combined action of shock and stress waves is developed,as well as the fracture propagation rules after the wedging of the water medium into the fractures.Finally,the results of deep-hole underwater blasting tests on large rocks confirm the efficient utilization of explosive in the hole to improve the safety conditions.Accordingly,safe and static rock breaking under the detonation of high-effect explosive can be achieved.In addition,super-dynamic loading from the explosions and static loading from the water medium in the hole can be adequately combined for rock breaking.展开更多
China has a rich resource of fragrant japonica rice that is gaining increasing consumers’ interests.In the present study,an untargeted gas chromatography-mass spectrometry-based metabolomics was employed to investiga...China has a rich resource of fragrant japonica rice that is gaining increasing consumers’ interests.In the present study,an untargeted gas chromatography-mass spectrometry-based metabolomics was employed to investigate the volatile profile of Chinese fragrant and non-fragrant japonica varieties.Partial least square discriminative analysis (PLS-DA) along with univariate analysis was taken to seek specific markers in raw and cooked Chinese japonica rice distinguishing fragrant and non-fragrant varieties.Volatile profile of raw Chinese japonica rice dominated by alkanes was completely different from that of cooked rice predominated by aldehydes.Thirteen and eleven volatile compounds were selected as the potential discriminative markers in raw and cooked Chinese japonica rice,respectively.Only 2-acetylpyrrole and decanal served as the specific marker in both raw and cooked Chinese japonica rice.Fragrant Chinese japonica rice varieties contained more 2-acetylpyrrole,(E )-2-octenal,nonanal,1-tetradecene,decanal and (E )-2-decenal in raw rice.While fragrant Chinese japonica rice varieties contained more 2-acetyl-1-pyrroline,2-acetylpyrrole,1-hexanol,decanal and indole in cooked rice.The results provided an in-depth understanding of volatile variation in raw and cooked form of aromatic and non-aromatic cultivars and will benefit rice adulteration identification and marker-assisted flavor breeding in the future.展开更多
The objective of this study was to investigate the effect of different germination times (0–48 h) on the quality characteristics, especially the volatile compounds, of fermented brown rice cake (FBRC). Post-germ...The objective of this study was to investigate the effect of different germination times (0–48 h) on the quality characteristics, especially the volatile compounds, of fermented brown rice cake (FBRC). Post-germination treatment, the viscoelasticity of the rice pulp decreased, also the hardness of FBRC steadily decreased. The 24 h germination time FBRC is considered to have the best quality including the smallest pore average area on the sliced surface and highest sensory score. In addition, the germination treatment also positively impacted the flavor of FBRC. Compared with the non-germination, the germinated groups had higher contents of alcohols, ketones, and heterocyclic compounds. The flavor volatile compounds could be generated via the amino acid metabolism and lipid oxidation pathways. A close correlation was found between the free amino acids, the free fatty acids and the main flavor volatile compounds. Principal component analysis indicated that the germination treatment improved the yeast flavor of brown rice cake;a short germination time was found best to provide a richer flavor. Overall, this study proved that moderate germination treatment effectively could improve the whole quality of FBRC.展开更多
The contribution of starch granules to the baking properties of frozen dough bread has been investigated using reconstituted dough method.The baking and aging characteristics of frozen dough bread were studied by text...The contribution of starch granules to the baking properties of frozen dough bread has been investigated using reconstituted dough method.The baking and aging characteristics of frozen dough bread were studied by texture analyzer,colorimeter,DSC,FTIR and LF-NMR.Results showed that starch had more impact on bread than gluten in specific volume of frozen dough bread,while gluten contributed more in color and cell density of frozen dough bread crumb during 8-weeks frozen storage.The changes of hardness mainly contributed to starch deterioration in first 4 weeks,then it was dominated by gluten in the later 4-8 weeks.A-Type granules have more effect on texture properties,number of cells and enthalpy of frozen dough bread during storage.B-Type granules contributed more on the size of cells in bread.The main aging change of wheat starch in profiles of bread was provided by A-Type granules during frozen storage.展开更多
This study aimed to improve the bread quality, especially aroma, using the fermented cream-soy protein isolate (SPI) flavor and reveal the improvement mechanisms. The cream with partially substituted SPI was fermented...This study aimed to improve the bread quality, especially aroma, using the fermented cream-soy protein isolate (SPI) flavor and reveal the improvement mechanisms. The cream with partially substituted SPI was fermented by lactic acid bacteria to enhance its flavor and used for bread making. The study also explored the positive effect of fermented cream on bread quality, especially the aroma formation. The bread quality was assessed by sensory evaluation, texture, and color determination, and the changes in bread dough characteristics were evaluated using a rheofermentometer and a dynamic rheometer. Furthermore, the influence of fermented cream-SPI flavor on bread volatile compounds (VOCs) was investigated using gas chromatography–mass spectrometry and principal component analysis. The results showed that the fermented cream-SPI flavor improved the texture of bread by increasing the gas production and the gluten strength of the dough. It reduced the crumb hardness from 337 ± 12 g to 171 ± 6 g and increased the specific volume from 3.51 ± 0.05 g/mL to 4.19 ± 0.06 g/mL. Moreover, the cream-SPI flavor improved the bread aroma by providing VOCs directly (acids, 2-nonanone, 2-undecanone, 2-tridecanone, and δ-dodecalactone) or precursor substances for VOC formation [esters, (E,E)-2,4-nonadienal, (E)-2-nonenal, and 1-octen-3-ol] during the bread-making process. The present study suggested that the partial substitution of SPI in cream after fermentation had great potential as a bread quality improver to enhance both the texture and aroma of bread.展开更多
基金National Natural Science Foundation of China(51604262)Foundation Research Project of Jiangsu Province(BK20160256)China Postdoctoral Science Foundation Project(2018M632424).
文摘The principles of fracture development during underwater blasting are examined based on explosion and impact dynamics,fluid dynamics,fracture dynamics,and field testing.The research reveals that the fracturing of the surrounding rock during underwater blasting is due to the combined action of shock and stress waves for the initial rock breakage and subsequent water expansion.The fracture development model for the surrounding rock of a drilling hole during underwater blasting is established.The rock fracturing range under the combined action of shock and stress waves is developed,as well as the fracture propagation rules after the wedging of the water medium into the fractures.Finally,the results of deep-hole underwater blasting tests on large rocks confirm the efficient utilization of explosive in the hole to improve the safety conditions.Accordingly,safe and static rock breaking under the detonation of high-effect explosive can be achieved.In addition,super-dynamic loading from the explosions and static loading from the water medium in the hole can be adequately combined for rock breaking.
基金greatly appreciate National Japonica Rice Engineering Technology Research Center and Yangzhou University for rice samples provided.This work was supported by the National Natural Science Support of China(No.31872905)the National Thirteenth Five-Year Plan for Science&Technology Support of China(2018YFD0400604)+3 种基金the China Postdoctoral Science Foundation(No.2020M671344)the Major scientific and technological innovation project of Shandong Province(2019JZZY010722)the foundation of State Key Laboratory of Biobased Materials and Green Papermaking,Qilu University of Technology,Shandong Academy of Science(No.KF201910)the National Natural Science Support of China(32001617).
文摘China has a rich resource of fragrant japonica rice that is gaining increasing consumers’ interests.In the present study,an untargeted gas chromatography-mass spectrometry-based metabolomics was employed to investigate the volatile profile of Chinese fragrant and non-fragrant japonica varieties.Partial least square discriminative analysis (PLS-DA) along with univariate analysis was taken to seek specific markers in raw and cooked Chinese japonica rice distinguishing fragrant and non-fragrant varieties.Volatile profile of raw Chinese japonica rice dominated by alkanes was completely different from that of cooked rice predominated by aldehydes.Thirteen and eleven volatile compounds were selected as the potential discriminative markers in raw and cooked Chinese japonica rice,respectively.Only 2-acetylpyrrole and decanal served as the specific marker in both raw and cooked Chinese japonica rice.Fragrant Chinese japonica rice varieties contained more 2-acetylpyrrole,(E )-2-octenal,nonanal,1-tetradecene,decanal and (E )-2-decenal in raw rice.While fragrant Chinese japonica rice varieties contained more 2-acetyl-1-pyrroline,2-acetylpyrrole,1-hexanol,decanal and indole in cooked rice.The results provided an in-depth understanding of volatile variation in raw and cooked form of aromatic and non-aromatic cultivars and will benefit rice adulteration identification and marker-assisted flavor breeding in the future.
基金supported by the National Key R&D Program of China(2021YFD2100200/2021YFD2100201).
文摘The objective of this study was to investigate the effect of different germination times (0–48 h) on the quality characteristics, especially the volatile compounds, of fermented brown rice cake (FBRC). Post-germination treatment, the viscoelasticity of the rice pulp decreased, also the hardness of FBRC steadily decreased. The 24 h germination time FBRC is considered to have the best quality including the smallest pore average area on the sliced surface and highest sensory score. In addition, the germination treatment also positively impacted the flavor of FBRC. Compared with the non-germination, the germinated groups had higher contents of alcohols, ketones, and heterocyclic compounds. The flavor volatile compounds could be generated via the amino acid metabolism and lipid oxidation pathways. A close correlation was found between the free amino acids, the free fatty acids and the main flavor volatile compounds. Principal component analysis indicated that the germination treatment improved the yeast flavor of brown rice cake;a short germination time was found best to provide a richer flavor. Overall, this study proved that moderate germination treatment effectively could improve the whole quality of FBRC.
基金supported by the National“Thirteenth Five-Year”Plan for Science&Technology Support of China(No.2018YFD0400604)National Natural Science Foundation of China(No.31872905)+1 种基金the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX20_1879)the China Scholarship Council(CSC,No.csc 202006790060).
文摘The contribution of starch granules to the baking properties of frozen dough bread has been investigated using reconstituted dough method.The baking and aging characteristics of frozen dough bread were studied by texture analyzer,colorimeter,DSC,FTIR and LF-NMR.Results showed that starch had more impact on bread than gluten in specific volume of frozen dough bread,while gluten contributed more in color and cell density of frozen dough bread crumb during 8-weeks frozen storage.The changes of hardness mainly contributed to starch deterioration in first 4 weeks,then it was dominated by gluten in the later 4-8 weeks.A-Type granules have more effect on texture properties,number of cells and enthalpy of frozen dough bread during storage.B-Type granules contributed more on the size of cells in bread.The main aging change of wheat starch in profiles of bread was provided by A-Type granules during frozen storage.
基金The National Natural Science Support of China(No.32001617).
文摘This study aimed to improve the bread quality, especially aroma, using the fermented cream-soy protein isolate (SPI) flavor and reveal the improvement mechanisms. The cream with partially substituted SPI was fermented by lactic acid bacteria to enhance its flavor and used for bread making. The study also explored the positive effect of fermented cream on bread quality, especially the aroma formation. The bread quality was assessed by sensory evaluation, texture, and color determination, and the changes in bread dough characteristics were evaluated using a rheofermentometer and a dynamic rheometer. Furthermore, the influence of fermented cream-SPI flavor on bread volatile compounds (VOCs) was investigated using gas chromatography–mass spectrometry and principal component analysis. The results showed that the fermented cream-SPI flavor improved the texture of bread by increasing the gas production and the gluten strength of the dough. It reduced the crumb hardness from 337 ± 12 g to 171 ± 6 g and increased the specific volume from 3.51 ± 0.05 g/mL to 4.19 ± 0.06 g/mL. Moreover, the cream-SPI flavor improved the bread aroma by providing VOCs directly (acids, 2-nonanone, 2-undecanone, 2-tridecanone, and δ-dodecalactone) or precursor substances for VOC formation [esters, (E,E)-2,4-nonadienal, (E)-2-nonenal, and 1-octen-3-ol] during the bread-making process. The present study suggested that the partial substitution of SPI in cream after fermentation had great potential as a bread quality improver to enhance both the texture and aroma of bread.
