A kind of layered Li;MSiO;material,Fe saponite with Na;pillaring (Na^(+)-FSAP) was developed as a lowcost and environment-friendly lithium-ion storage material.The Na^(+)-FSAP follows the insertion/deinsertion working...A kind of layered Li;MSiO;material,Fe saponite with Na;pillaring (Na^(+)-FSAP) was developed as a lowcost and environment-friendly lithium-ion storage material.The Na^(+)-FSAP follows the insertion/deinsertion working mechanism accompanied by valence change of Fe from Fe^(1.86+) to Fe^(2.71+) (average value) after stabilization,and displays a specific capacity of 125 m Ah g^(-1) at 50 m A g^(-1) with retention ratio of 80.8%after 75 cycles.The Na^(+)-pillaring effect and abundant structural water in the gallery urge Li^(+) migrate rapidly,resulting in a large Li^(+) diffusion coefficient within a range of 10^(-6.5)–10^(-7.5) cm^(2)s^(-1).Thus,the Na^(+)-FSAP provides a model material to design electrode materials with rapid lithium-ion migration and has great potential to take place of polyanionic-type Li_(2)MSiO_(4)(M=Mn,Fe,Co) cathode materials.展开更多
为实现天问一号着陆点快速精确定位,规划火星车行驶路径,并将火星车后续数据纳入统一的地理坐标系,本研究利用着陆初期有限数据(天问一号环绕器获取的遥感影像、一幅悬停避障缓速下降阶段的GNC(guidance,navigation and control)避障敏...为实现天问一号着陆点快速精确定位,规划火星车行驶路径,并将火星车后续数据纳入统一的地理坐标系,本研究利用着陆初期有限数据(天问一号环绕器获取的遥感影像、一幅悬停避障缓速下降阶段的GNC(guidance,navigation and control)避障敏感器拍摄的降落影像和导航相机在着陆平台的环拍立体像对)完成定位任务.首先,通过导航相机的环拍影像生成着陆点周围陨石坑、沙丘、火山口、山梁之间的拓扑关系.然后,以根据环绕器的遥感影像生成的数字正射影像图(digital orthophoto map,DOM)为底图,将导航相机生成的陨石坑、沙丘、火山口、山梁之间的拓扑关系与底图预着陆区的陨石坑、沙丘、火山口、山梁之间的拓扑关系进行模糊匹配,以确定疑似着陆点,并结合降落影像在疑似着陆点中确定着陆点的粗略位置.最后,根据导航相机影像多像空间后方交会解算着陆点的精确位置为109.925°E,25.066°N.展开更多
基金supported by the National Natural Science Foundation of China(21671015 and U1707603)the Fundamental Research Funds for the Central Universities(XK1802-6,BHYC1702B,and XK1803-05)the Beijing Municipal Science&Technology Commission(Z191100002019013)。
文摘A kind of layered Li;MSiO;material,Fe saponite with Na;pillaring (Na^(+)-FSAP) was developed as a lowcost and environment-friendly lithium-ion storage material.The Na^(+)-FSAP follows the insertion/deinsertion working mechanism accompanied by valence change of Fe from Fe^(1.86+) to Fe^(2.71+) (average value) after stabilization,and displays a specific capacity of 125 m Ah g^(-1) at 50 m A g^(-1) with retention ratio of 80.8%after 75 cycles.The Na^(+)-pillaring effect and abundant structural water in the gallery urge Li^(+) migrate rapidly,resulting in a large Li^(+) diffusion coefficient within a range of 10^(-6.5)–10^(-7.5) cm^(2)s^(-1).Thus,the Na^(+)-FSAP provides a model material to design electrode materials with rapid lithium-ion migration and has great potential to take place of polyanionic-type Li_(2)MSiO_(4)(M=Mn,Fe,Co) cathode materials.
文摘为实现天问一号着陆点快速精确定位,规划火星车行驶路径,并将火星车后续数据纳入统一的地理坐标系,本研究利用着陆初期有限数据(天问一号环绕器获取的遥感影像、一幅悬停避障缓速下降阶段的GNC(guidance,navigation and control)避障敏感器拍摄的降落影像和导航相机在着陆平台的环拍立体像对)完成定位任务.首先,通过导航相机的环拍影像生成着陆点周围陨石坑、沙丘、火山口、山梁之间的拓扑关系.然后,以根据环绕器的遥感影像生成的数字正射影像图(digital orthophoto map,DOM)为底图,将导航相机生成的陨石坑、沙丘、火山口、山梁之间的拓扑关系与底图预着陆区的陨石坑、沙丘、火山口、山梁之间的拓扑关系进行模糊匹配,以确定疑似着陆点,并结合降落影像在疑似着陆点中确定着陆点的粗略位置.最后,根据导航相机影像多像空间后方交会解算着陆点的精确位置为109.925°E,25.066°N.
