Pumping artesian water from porous media inevitably reduces the groundwater head and promotes soil consolidation,which may result in regional land subsidence.In this study,a fluid-mechanical coupled numerical model is...Pumping artesian water from porous media inevitably reduces the groundwater head and promotes soil consolidation,which may result in regional land subsidence.In this study,a fluid-mechanical coupled numerical model is developed to investigate the dewatering-induced groundwater drawdown and deformation responses for multi-layer strata.The relation bet ween the stra tum deformation and groundwater drawdown is discussed.The results show that the pumping process can be divided into four st ages.The development of vertical deformation is inconsistent with the change of the pore pressure for the strata except for the confined aquifer at the early stage of pumping.The st rata expand while the pore pressures reduce.This inconsistency may be due to the large unloading in the confined aquifer at the early stage of pumping.Soil arch comes into being owing to the constraint of the surrounding soils when the large unloading occurs in the confined aquifer;this can reduce the stratum compression and cause the expansion of the layers.It can be concluded that as the pumping continues,the decrease of the pore pressure dominates the vertical deformation and results in the soil compression in all strata.展开更多
采用顶空固相微萃取(HS-SPME)方法,结合气相色谱-嗅闻-质谱联用仪(GC-O-MS),对六款不同色度的特种麦芽(高香麦芽、饼干麦芽、焦香麦芽、结晶麦芽、巧克力麦芽和黑麦芽)进行挥发性风味物质鉴定,从六款特种麦芽中一共鉴定出风味化合物41种...采用顶空固相微萃取(HS-SPME)方法,结合气相色谱-嗅闻-质谱联用仪(GC-O-MS),对六款不同色度的特种麦芽(高香麦芽、饼干麦芽、焦香麦芽、结晶麦芽、巧克力麦芽和黑麦芽)进行挥发性风味物质鉴定,从六款特种麦芽中一共鉴定出风味化合物41种,其中醛类20种、吡嗪类7种、醇类4种、酚类1种、杂环化合物类9种。采用Rate That All Apply(RATA)感官评价方法对特种麦芽的感官特性强度进行打分,结果表明,随着特种麦芽颜色的加深,其甜香果香逐渐降低,咖啡味和烟熏味逐渐增加。通过偏最小二乘回归法(PLSR)建立特种麦芽风味物质与感官特性的相关性,结果表明不同种类杂环化合物的协同作用解释了巧克力麦芽和黑麦芽的主体风味,不同种类吡嗪化合物的协同作用解释了饼干麦芽的主体风味,但该模型对高香麦芽、焦香麦芽、结晶麦芽的主体风味解释欠佳,有待下一步探索。展开更多
基金the National Natural Science Foundation of China(Nos.41602283 and 41727802)the Shanghai Rising-Star Program(No.19QC1400800)
文摘Pumping artesian water from porous media inevitably reduces the groundwater head and promotes soil consolidation,which may result in regional land subsidence.In this study,a fluid-mechanical coupled numerical model is developed to investigate the dewatering-induced groundwater drawdown and deformation responses for multi-layer strata.The relation bet ween the stra tum deformation and groundwater drawdown is discussed.The results show that the pumping process can be divided into four st ages.The development of vertical deformation is inconsistent with the change of the pore pressure for the strata except for the confined aquifer at the early stage of pumping.The st rata expand while the pore pressures reduce.This inconsistency may be due to the large unloading in the confined aquifer at the early stage of pumping.Soil arch comes into being owing to the constraint of the surrounding soils when the large unloading occurs in the confined aquifer;this can reduce the stratum compression and cause the expansion of the layers.It can be concluded that as the pumping continues,the decrease of the pore pressure dominates the vertical deformation and results in the soil compression in all strata.
文摘采用顶空固相微萃取(HS-SPME)方法,结合气相色谱-嗅闻-质谱联用仪(GC-O-MS),对六款不同色度的特种麦芽(高香麦芽、饼干麦芽、焦香麦芽、结晶麦芽、巧克力麦芽和黑麦芽)进行挥发性风味物质鉴定,从六款特种麦芽中一共鉴定出风味化合物41种,其中醛类20种、吡嗪类7种、醇类4种、酚类1种、杂环化合物类9种。采用Rate That All Apply(RATA)感官评价方法对特种麦芽的感官特性强度进行打分,结果表明,随着特种麦芽颜色的加深,其甜香果香逐渐降低,咖啡味和烟熏味逐渐增加。通过偏最小二乘回归法(PLSR)建立特种麦芽风味物质与感官特性的相关性,结果表明不同种类杂环化合物的协同作用解释了巧克力麦芽和黑麦芽的主体风味,不同种类吡嗪化合物的协同作用解释了饼干麦芽的主体风味,但该模型对高香麦芽、焦香麦芽、结晶麦芽的主体风味解释欠佳,有待下一步探索。
