模拟研究京津冀地区地表土壤热通量,对该区域的干旱监测、生态系统功能评估、气候变化模拟及农作物估产具有重要参考意义.基于京津冀地区怀来站和馆陶站2个站点每10 min的自动气象站数据(四分量辐射、地表辐射温度、土壤热通量、多层土...模拟研究京津冀地区地表土壤热通量,对该区域的干旱监测、生态系统功能评估、气候变化模拟及农作物估产具有重要参考意义.基于京津冀地区怀来站和馆陶站2个站点每10 min的自动气象站数据(四分量辐射、地表辐射温度、土壤热通量、多层土壤水分和土壤温度),通过昼夜分开调整G_(0)_SEBS模型,构建了适用于京津冀地区的新模型G_(0)_SEBSadj.利用GLASS和GLDAS区域数据驱动G_(0)_SEBSadj模型,定量模拟了京津冀地区2010-2020年较高精度的地表土壤热通量(G_(0)),分析得出该区域近11 a G_(0)的时空变化特征.2010-2020年,京津冀地区G_(0)波动上升,这可能与全球气候变暖趋势密切相关;空间上,京津冀地区西北区域年均G_(0)较高,而太行山等海拔较高区域年均G_(0)较低,这可能与海拔地形影响相关.研究得出了京津冀地区2010-2020年地表土壤热通量的区域数据,揭示了该地区G_(0)的时空分布特征,为区域蒸散发及相关研究提供了数据支持及参考.展开更多
为了减少荔枝汁在加热后产生的“蒸煮”异味,筛选了邻苯三酚、没食子酸、迷迭香酸、儿茶素、抗坏血酸及葡萄糖氧化酶六种抑制剂,从色泽、pH、香气轮廓、电子鼻、挥发性成分、降硫率以及总酚、总黄酮、抗氧化特性等角度去评价六种抑制剂...为了减少荔枝汁在加热后产生的“蒸煮”异味,筛选了邻苯三酚、没食子酸、迷迭香酸、儿茶素、抗坏血酸及葡萄糖氧化酶六种抑制剂,从色泽、pH、香气轮廓、电子鼻、挥发性成分、降硫率以及总酚、总黄酮、抗氧化特性等角度去评价六种抑制剂对荔枝汁风味及营养品质的影响。结果显示抗坏血酸和没食子酸抑制剂处理的样品与新鲜汁相比的色差值最小;整体香气轮廓显示葡萄糖氧化酶抑制蒸煮异味效果最佳,其次为迷迭香酸;电子鼻结果显示葡萄糖氧化酶处理的荔枝汁与新鲜汁最为接近,其次是儿茶素和邻苯三酚。挥发性成分的主成分分析结果显示抗坏血酸抑制剂处理的样品与新鲜汁最接近,其次为没食子酸、儿茶素、迷迭香酸。降硫率结果显示葡萄糖氧化酶的降硫效果最为显著,对二甲基硫醚、二甲基三硫醚、甲硫基丙醛的抑制率均达到100%,对二甲基二硫醚的抑制率为61.11%。营养品质方面,多酚类抑制剂与抗坏血酸处理的总酚、总黄酮含量和抗氧化性较新鲜汁均显著上升(P<0.05),而葡萄糖氧化酶处理的总酚、总黄酮含量较新鲜汁上升但抗氧化活性与新鲜汁无显著差异。综合色泽、pH、香气轮廓、营养品质以及降硫效果等因素进行偏最小二乘判别分析(partial least squares discriminant analysis,PLS-DA),发现葡萄糖氧化酶对荔枝汁整体品质影响最好。本研究可为荔枝以及其他热敏性水果加工过程中品质提升提供参考依据。展开更多
Analysis of the environmental and economic performance of fishing vessels has received limited attention compared with other ship types despite their notable contribution to global greenhouse gas(GHG)emissions.This st...Analysis of the environmental and economic performance of fishing vessels has received limited attention compared with other ship types despite their notable contribution to global greenhouse gas(GHG)emissions.This study evaluates the carbon footprint(CF)and economic viability of a liquefied natural gas(LNG)-fueled fishing vessel,using real engine operation simulations to provide precise and dynamic evaluation of fuel consumption and GHG emissions.Operational profiles are obtained through the utilization of onboard monitoring systems,whereas engine performance is simulated using the 1D/0D AVL Boost^(TM)model.Life cycle assessment(LCA)is conducted to quantify the environmental impact,whereas life cycle cost assessment(LCCA)is performed to analyze the profitability of LNG as an alternative fuel.The potential impact of the future fuel price uncertainties is addressed using Monte Carlo simulations.The LCA findings indicate that LNG has the potential to reduce the CF of the vessel by 14%to 16%,in comparison to a diesel power system configuration that serves as the baseline scenario.The LCCA results further indicate that the total cost of an LNG-powered ship is lower by 9.5%-13.8%,depending on the share of LNG and pilot fuels.This finding highlights the potential of LNG to produce considerable environmental benefits while addressing economic challenges under diverse operational and fuel price conditions.展开更多
Low-cost and high-safety aqueous Zn-I_(2) batteries attract extensive attention for large-scale energy storage systems.However,polyiodide shuttling and sluggish iodine conversion reactions lead to inferior rate capabi...Low-cost and high-safety aqueous Zn-I_(2) batteries attract extensive attention for large-scale energy storage systems.However,polyiodide shuttling and sluggish iodine conversion reactions lead to inferior rate capability and severe capacity decay.Herein,a three-dimensional polyaniline is wrapped by carboxylcarbon nanotubes(denoted as C-PANI)which is designed as a catalytic cathode to effectively boost iodine conversion with suppressed polyiodide shuttling,thereby improving Zn-I_(2) batteries.Specifically,carboxyl-carbon nanotubes serve as a proton reservoir for more protonated-NH+=sites in PANI chains,achieving a direct I0/I−reaction for suppressed polyiodide generation and Zn corrosion.Attributing to this“proton-iodine”regulation,catalytic protonated C-PANI strongly fixes electrolytic iodine species and stores proton ions simultaneously through reversible-N=/-NH^(+)-reaction.Therefore,the electrolytic Zn-I_(2) battery with C-PANI cathode exhibits an impressive capacity of 420 mAh g^(−1) and ultra-long lifespan over 40,000 cycles.Additionally,a 60 mAh pouch cell was assembled with excellent cycling stability after 100 cycles,providing new insights into exploring effective organocatalysts for superb Zn-halogen batteries.展开更多
文摘模拟研究京津冀地区地表土壤热通量,对该区域的干旱监测、生态系统功能评估、气候变化模拟及农作物估产具有重要参考意义.基于京津冀地区怀来站和馆陶站2个站点每10 min的自动气象站数据(四分量辐射、地表辐射温度、土壤热通量、多层土壤水分和土壤温度),通过昼夜分开调整G_(0)_SEBS模型,构建了适用于京津冀地区的新模型G_(0)_SEBSadj.利用GLASS和GLDAS区域数据驱动G_(0)_SEBSadj模型,定量模拟了京津冀地区2010-2020年较高精度的地表土壤热通量(G_(0)),分析得出该区域近11 a G_(0)的时空变化特征.2010-2020年,京津冀地区G_(0)波动上升,这可能与全球气候变暖趋势密切相关;空间上,京津冀地区西北区域年均G_(0)较高,而太行山等海拔较高区域年均G_(0)较低,这可能与海拔地形影响相关.研究得出了京津冀地区2010-2020年地表土壤热通量的区域数据,揭示了该地区G_(0)的时空分布特征,为区域蒸散发及相关研究提供了数据支持及参考.
文摘为了减少荔枝汁在加热后产生的“蒸煮”异味,筛选了邻苯三酚、没食子酸、迷迭香酸、儿茶素、抗坏血酸及葡萄糖氧化酶六种抑制剂,从色泽、pH、香气轮廓、电子鼻、挥发性成分、降硫率以及总酚、总黄酮、抗氧化特性等角度去评价六种抑制剂对荔枝汁风味及营养品质的影响。结果显示抗坏血酸和没食子酸抑制剂处理的样品与新鲜汁相比的色差值最小;整体香气轮廓显示葡萄糖氧化酶抑制蒸煮异味效果最佳,其次为迷迭香酸;电子鼻结果显示葡萄糖氧化酶处理的荔枝汁与新鲜汁最为接近,其次是儿茶素和邻苯三酚。挥发性成分的主成分分析结果显示抗坏血酸抑制剂处理的样品与新鲜汁最接近,其次为没食子酸、儿茶素、迷迭香酸。降硫率结果显示葡萄糖氧化酶的降硫效果最为显著,对二甲基硫醚、二甲基三硫醚、甲硫基丙醛的抑制率均达到100%,对二甲基二硫醚的抑制率为61.11%。营养品质方面,多酚类抑制剂与抗坏血酸处理的总酚、总黄酮含量和抗氧化性较新鲜汁均显著上升(P<0.05),而葡萄糖氧化酶处理的总酚、总黄酮含量较新鲜汁上升但抗氧化活性与新鲜汁无显著差异。综合色泽、pH、香气轮廓、营养品质以及降硫效果等因素进行偏最小二乘判别分析(partial least squares discriminant analysis,PLS-DA),发现葡萄糖氧化酶对荔枝汁整体品质影响最好。本研究可为荔枝以及其他热敏性水果加工过程中品质提升提供参考依据。
文摘Analysis of the environmental and economic performance of fishing vessels has received limited attention compared with other ship types despite their notable contribution to global greenhouse gas(GHG)emissions.This study evaluates the carbon footprint(CF)and economic viability of a liquefied natural gas(LNG)-fueled fishing vessel,using real engine operation simulations to provide precise and dynamic evaluation of fuel consumption and GHG emissions.Operational profiles are obtained through the utilization of onboard monitoring systems,whereas engine performance is simulated using the 1D/0D AVL Boost^(TM)model.Life cycle assessment(LCA)is conducted to quantify the environmental impact,whereas life cycle cost assessment(LCCA)is performed to analyze the profitability of LNG as an alternative fuel.The potential impact of the future fuel price uncertainties is addressed using Monte Carlo simulations.The LCA findings indicate that LNG has the potential to reduce the CF of the vessel by 14%to 16%,in comparison to a diesel power system configuration that serves as the baseline scenario.The LCCA results further indicate that the total cost of an LNG-powered ship is lower by 9.5%-13.8%,depending on the share of LNG and pilot fuels.This finding highlights the potential of LNG to produce considerable environmental benefits while addressing economic challenges under diverse operational and fuel price conditions.
基金supported by the National Natural Science Foundation of China(22209006,21935001)the Natural Science Foundation of Shandong Province(ZR2022QE009)+1 种基金Fundamental Research Funds for the Central Universities(buctrc202307)the Beijing Natural Science Foundation(Z210016).
文摘Low-cost and high-safety aqueous Zn-I_(2) batteries attract extensive attention for large-scale energy storage systems.However,polyiodide shuttling and sluggish iodine conversion reactions lead to inferior rate capability and severe capacity decay.Herein,a three-dimensional polyaniline is wrapped by carboxylcarbon nanotubes(denoted as C-PANI)which is designed as a catalytic cathode to effectively boost iodine conversion with suppressed polyiodide shuttling,thereby improving Zn-I_(2) batteries.Specifically,carboxyl-carbon nanotubes serve as a proton reservoir for more protonated-NH+=sites in PANI chains,achieving a direct I0/I−reaction for suppressed polyiodide generation and Zn corrosion.Attributing to this“proton-iodine”regulation,catalytic protonated C-PANI strongly fixes electrolytic iodine species and stores proton ions simultaneously through reversible-N=/-NH^(+)-reaction.Therefore,the electrolytic Zn-I_(2) battery with C-PANI cathode exhibits an impressive capacity of 420 mAh g^(−1) and ultra-long lifespan over 40,000 cycles.Additionally,a 60 mAh pouch cell was assembled with excellent cycling stability after 100 cycles,providing new insights into exploring effective organocatalysts for superb Zn-halogen batteries.