介绍一种基于一阶辐射传输的积雪散射模型。该模型考虑了积雪覆盖地表微波散射的3种回波分量:雪层表面散射、下垫面散射以及雪层体散射。对于其中2个面散射分量,文章中应用一种新的面散射模型———AIEM取代原有的IEM模型进行处理。最后...介绍一种基于一阶辐射传输的积雪散射模型。该模型考虑了积雪覆盖地表微波散射的3种回波分量:雪层表面散射、下垫面散射以及雪层体散射。对于其中2个面散射分量,文章中应用一种新的面散射模型———AIEM取代原有的IEM模型进行处理。最后,使用M ich igan大学的实测数据对改进后模型的模拟结果进行验证,并与改进前的模拟结果进行了对比。展开更多
土壤水分是气象预报、农情监测以及水文模型的重要参数之一,利用被动微波遥感技术可以有效获取土壤水分。欧空局(ESA)计划于2009年发射卫星SMOS(Soil Moisture and Ocean Salinity),其主要目的是监测全球范围内的土壤水分和海洋盐度变...土壤水分是气象预报、农情监测以及水文模型的重要参数之一,利用被动微波遥感技术可以有效获取土壤水分。欧空局(ESA)计划于2009年发射卫星SMOS(Soil Moisture and Ocean Salinity),其主要目的是监测全球范围内的土壤水分和海洋盐度变化。根据SMOS的设置情况,寻找精度较高的半经验模型以便为进一步的土壤水分反演提供简化模型。对于裸露地表,地表粗糙度、土壤介电常数等因素影响最终的微波发射率。运用Dobson半经验介电常数模型计算土壤的介电常数,将计算结果输入高级积分方程模型(AIEM)。通过AIEM模拟的数据库,利用回归关系建立了一个精度相对较高的L波段多角度半经验模型。展开更多
Vanadium redox flow battery(VRB),as the most promising large-scale electrical energy storage units,has attracted extensive attention.Amphoteric ion exchange membrane(AIEM),as the core part of VRB,separates electrolyte...Vanadium redox flow battery(VRB),as the most promising large-scale electrical energy storage units,has attracted extensive attention.Amphoteric ion exchange membrane(AIEM),as the core part of VRB,separates electrolyte on both sides of electrolytic tank and conducts H+.The AIEM with cation and anion groups possesses excellent performances,such as high ion conductivity(σ),low vanadium ion permeability(Pvn+),relative stability and low cost.However,the performance of AIEM directly depends on the chemical structure of polymers.In addition to ensuring foundational physical performance,ion selectivity of AIEM is significant since the crossover of vanadium ion with various valences may reduce the battery capacity.In this paper,AIEMs for VRB and their chemical structures as well as synthesis approaches to realize all kinds of high-performing AIEMs are reviewed.The current trend and future direction of prospective materials for the VRB separators are documented in detail as well.展开更多
文摘介绍一种基于一阶辐射传输的积雪散射模型。该模型考虑了积雪覆盖地表微波散射的3种回波分量:雪层表面散射、下垫面散射以及雪层体散射。对于其中2个面散射分量,文章中应用一种新的面散射模型———AIEM取代原有的IEM模型进行处理。最后,使用M ich igan大学的实测数据对改进后模型的模拟结果进行验证,并与改进前的模拟结果进行了对比。
文摘土壤水分是气象预报、农情监测以及水文模型的重要参数之一,利用被动微波遥感技术可以有效获取土壤水分。欧空局(ESA)计划于2009年发射卫星SMOS(Soil Moisture and Ocean Salinity),其主要目的是监测全球范围内的土壤水分和海洋盐度变化。根据SMOS的设置情况,寻找精度较高的半经验模型以便为进一步的土壤水分反演提供简化模型。对于裸露地表,地表粗糙度、土壤介电常数等因素影响最终的微波发射率。运用Dobson半经验介电常数模型计算土壤的介电常数,将计算结果输入高级积分方程模型(AIEM)。通过AIEM模拟的数据库,利用回归关系建立了一个精度相对较高的L波段多角度半经验模型。
基金the National Natural Science Foundation of China(Nos.51503187,21504037 and 51603194)the National key R&D Project(No.2016YFE0102700)+3 种基金the Shanxi provincial foundation for science and technology research(Nos.201601D021058,201701D221050,20181101006,20181102019)Partial support is also from the NIMHD-RCMI grant number 5G12MD007595 from the National Institute of Minority HealthHealth Disparities and the NIGMS-BUILD(No.8UL1GM118967)National Science Foundation(No.1700429)。
文摘Vanadium redox flow battery(VRB),as the most promising large-scale electrical energy storage units,has attracted extensive attention.Amphoteric ion exchange membrane(AIEM),as the core part of VRB,separates electrolyte on both sides of electrolytic tank and conducts H+.The AIEM with cation and anion groups possesses excellent performances,such as high ion conductivity(σ),low vanadium ion permeability(Pvn+),relative stability and low cost.However,the performance of AIEM directly depends on the chemical structure of polymers.In addition to ensuring foundational physical performance,ion selectivity of AIEM is significant since the crossover of vanadium ion with various valences may reduce the battery capacity.In this paper,AIEMs for VRB and their chemical structures as well as synthesis approaches to realize all kinds of high-performing AIEMs are reviewed.The current trend and future direction of prospective materials for the VRB separators are documented in detail as well.
