Coastal wetlands possess significant carbon sequestration rates and storage capabilities.Clarifying the methods for evaluating coastal wetland carbon sinks and identifying existing issues are essential for accurately ...Coastal wetlands possess significant carbon sequestration rates and storage capabilities.Clarifying the methods for evaluating coastal wetland carbon sinks and identifying existing issues are essential for accurately assessing coastal blue carbon,understanding the carbon balance between terrestrial-coastal-marine ecosystems,and advancing the“dual carbon”goal.This paper reviews the detailed processes of coastal wetland carbon cycling and summarizes the challenges and difficulties in defining,delineating,and identifying the boundaries of coastal wetlands.We generalize current carbon sink evaluation methods across different dimensions by constructing a“black box theory”.In addition,based on the“white box theory”,we propose a net ecosystem carbon balance model for carbon sink assessment,providing a theoretical foundation for enhancing the understanding of coastal wetland carbon sinks and optimizing the evaluation system for coastal blue carbon functionality.We also systematically summarize the current status of carbon sources and sinks in China's coastal wetlands and propose a technical framework for emission reduction and carbon sequestration enhancement through integrated management of coastal zones and wetlands and regulation of key wetland ecological processes,with the aim of increasing the potential of blue carbon in mitigating climate change.Finally,based on the current research gaps,we outline future research priorities for coastal wetland blue carbon.展开更多
A localized flexible airfoil at low Reynolds numbers is modeled and the aerodynamic performance is analyzed numerically.With characteristic based split scheme,a fluid solver for two dimensional incompressible Navier-S...A localized flexible airfoil at low Reynolds numbers is modeled and the aerodynamic performance is analyzed numerically.With characteristic based split scheme,a fluid solver for two dimensional incompressible Navier-Stokes equations is developed under the ALE framework,coupled with the theory of shallow arch,which is approximated by Galerkin method.Further,the interactions between the unsteady flow and the shallow arch are studied in detail.In particular,the effect of the selfexcited vibration of the structure on aerodynamic performance of the airfoil is investigated deeply at various angles of attack.The results show that the lift-to-drag ratio has been increased greatly compared with the rigid airfoil.Finally,the relationship between the self-excited vibration and the evolution of the flow is analyzed using FFT tools.展开更多
Light color and savory flavor are difficult to be integrated in‘Thermal Process Flavoring’through traditional Maillard reaction.A light-colored seasoning from gluten peptide-glucose system was prepared through gradi...Light color and savory flavor are difficult to be integrated in‘Thermal Process Flavoring’through traditional Maillard reaction.A light-colored seasoning from gluten peptide-glucose system was prepared through gradient temperature-elevating Maillard reaction with extra-added L-cysteine.Greater saltiness and umami enhancement effect of Maillard reaction products(MRPs)were observed from weaker reaction,while lower temperature and longer heating time were conducive to yield kokumi-taste compounds.With the addition of L-cysteine,intensities of fluorescence and UV-VIS absorption of MRPs were weakened.An inhibition of browning and a decrease ofα-dicarbonyls concentration caused by L-cysteine were observed.The addition of L-cysteine also led to an increase of peptides below 500 Da(from 53.27 mg/mL to 56.50 mg/mL)and a decrease of cross-linking products in 1-3 kDa,which accounted for superior umami and gentle kokumi attribute of the light-colored products compared with the MRPs without L-cysteine addition.展开更多
Two examples of the use of vortex control to reduce noise and enhance the stable operating range of a centrifugal compressor are presented in this paper.In the case of high-flow operation of a centrifugal compressor w...Two examples of the use of vortex control to reduce noise and enhance the stable operating range of a centrifugal compressor are presented in this paper.In the case of high-flow operation of a centrifugal compressor with a vaned diffuser,a discrete frequency noise induced by interaction between the impeller-discharge flow and the diffuser vane,which appears most notably in the power spectra of the radiated noise,can be reduced using a tapered diffuser vane(TDV) without affecting the performance of the compressor.Twin longitudinal vortices produced by leakage flow passing through the tapered portion of the diffuser vane induce secondary flow in the direction of the blade surface and prevent flow separation from the leading edge of the diffuser.The use of a TDV can effectively reduce both the discrete frequency noise generated by the interaction between the impeller-discharge flow and the diffuser surface and the broadband turbulent noise component.In the case of low-flow operation,a leading-edge vortex(LEV) that forms on the shroud side of the suction surface near the leading edge of the diffuser increases significantly in size and blocks flow in the diffuser passage.The formation of an LEV may adversely affect the performance of the compressor and may cause the diffuser to stall.Using a one-side tapered diffuser vane to suppress the evolution of an LEV,the stable operating range of the compressor can be increased by more than 12 percent,and the pressure-rise characteristics of the compressor can be improved.The results of a supplementary examination of the structure and unsteady behavior of LEVs,conducted by means of detailed numerical simulations,are also presented.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.31988102)the Major Project of the National Natural Science Foundation of China(Grant No.42293262)。
文摘Coastal wetlands possess significant carbon sequestration rates and storage capabilities.Clarifying the methods for evaluating coastal wetland carbon sinks and identifying existing issues are essential for accurately assessing coastal blue carbon,understanding the carbon balance between terrestrial-coastal-marine ecosystems,and advancing the“dual carbon”goal.This paper reviews the detailed processes of coastal wetland carbon cycling and summarizes the challenges and difficulties in defining,delineating,and identifying the boundaries of coastal wetlands.We generalize current carbon sink evaluation methods across different dimensions by constructing a“black box theory”.In addition,based on the“white box theory”,we propose a net ecosystem carbon balance model for carbon sink assessment,providing a theoretical foundation for enhancing the understanding of coastal wetland carbon sinks and optimizing the evaluation system for coastal blue carbon functionality.We also systematically summarize the current status of carbon sources and sinks in China's coastal wetlands and propose a technical framework for emission reduction and carbon sequestration enhancement through integrated management of coastal zones and wetlands and regulation of key wetland ecological processes,with the aim of increasing the potential of blue carbon in mitigating climate change.Finally,based on the current research gaps,we outline future research priorities for coastal wetland blue carbon.
基金This research is supported by Program for New Century Excellent Talents in University in China,No.NCET-07-0685.
文摘A localized flexible airfoil at low Reynolds numbers is modeled and the aerodynamic performance is analyzed numerically.With characteristic based split scheme,a fluid solver for two dimensional incompressible Navier-Stokes equations is developed under the ALE framework,coupled with the theory of shallow arch,which is approximated by Galerkin method.Further,the interactions between the unsteady flow and the shallow arch are studied in detail.In particular,the effect of the selfexcited vibration of the structure on aerodynamic performance of the airfoil is investigated deeply at various angles of attack.The results show that the lift-to-drag ratio has been increased greatly compared with the rigid airfoil.Finally,the relationship between the self-excited vibration and the evolution of the flow is analyzed using FFT tools.
基金This research was supported by the Key Science and Technology Program of Anhui Province(202203a06020012)National Natural Science Foundation of China(32172330)+3 种基金Natural Science Foundation of Jiangsu Province(BK20200597)the Fundamental Research Funds for the Central Universities(JUSRP122040)National First-class Discipline Program of Food Science and Technology(JUFSTR20180204)“Collaborative innovation center of food safety and quality control in Jiangsu Province”.
文摘Light color and savory flavor are difficult to be integrated in‘Thermal Process Flavoring’through traditional Maillard reaction.A light-colored seasoning from gluten peptide-glucose system was prepared through gradient temperature-elevating Maillard reaction with extra-added L-cysteine.Greater saltiness and umami enhancement effect of Maillard reaction products(MRPs)were observed from weaker reaction,while lower temperature and longer heating time were conducive to yield kokumi-taste compounds.With the addition of L-cysteine,intensities of fluorescence and UV-VIS absorption of MRPs were weakened.An inhibition of browning and a decrease ofα-dicarbonyls concentration caused by L-cysteine were observed.The addition of L-cysteine also led to an increase of peptides below 500 Da(from 53.27 mg/mL to 56.50 mg/mL)and a decrease of cross-linking products in 1-3 kDa,which accounted for superior umami and gentle kokumi attribute of the light-colored products compared with the MRPs without L-cysteine addition.
文摘Two examples of the use of vortex control to reduce noise and enhance the stable operating range of a centrifugal compressor are presented in this paper.In the case of high-flow operation of a centrifugal compressor with a vaned diffuser,a discrete frequency noise induced by interaction between the impeller-discharge flow and the diffuser vane,which appears most notably in the power spectra of the radiated noise,can be reduced using a tapered diffuser vane(TDV) without affecting the performance of the compressor.Twin longitudinal vortices produced by leakage flow passing through the tapered portion of the diffuser vane induce secondary flow in the direction of the blade surface and prevent flow separation from the leading edge of the diffuser.The use of a TDV can effectively reduce both the discrete frequency noise generated by the interaction between the impeller-discharge flow and the diffuser surface and the broadband turbulent noise component.In the case of low-flow operation,a leading-edge vortex(LEV) that forms on the shroud side of the suction surface near the leading edge of the diffuser increases significantly in size and blocks flow in the diffuser passage.The formation of an LEV may adversely affect the performance of the compressor and may cause the diffuser to stall.Using a one-side tapered diffuser vane to suppress the evolution of an LEV,the stable operating range of the compressor can be increased by more than 12 percent,and the pressure-rise characteristics of the compressor can be improved.The results of a supplementary examination of the structure and unsteady behavior of LEVs,conducted by means of detailed numerical simulations,are also presented.
