LiNi_(0.5)Mn_(1.5)O_4(LNMO) was prepared by a high-temperature solid phase method,and then Al PO_(4)(AP) was coated on the polyhedral LNMO surface by the wet chemical method.The experimental results showed that the LN...LiNi_(0.5)Mn_(1.5)O_4(LNMO) was prepared by a high-temperature solid phase method,and then Al PO_(4)(AP) was coated on the polyhedral LNMO surface by the wet chemical method.The experimental results showed that the LNMO-1%AP|Li cell prepared with a 1%mass ratio of Al PO_(4and) LNMO had better electrochemical performance;after 450 cycles at 1C,its discharge specific capacity maintained 108.78 m Ah·g^(-1),while that of the LNMO|Li cell was only 86.04 m Ah·g^(-1).Especially at the high rates of 5C and 10C,the electrochemical properties of the former were far superior to the latter.This was attributed to the fact that the AP coating made the surface of LNMO in contact with the electrolyte more stable,effectively promoted the Li~+transport,and reduced the polarization voltage of the electrode.展开更多
为简化前处理过程,降低方法的检出限,进行了题示研究。采集鱼塘底泥样品,混匀、缩分、冷冻干燥、除杂、研磨、过筛后混匀,分取5.00 g,加入10.0μg·L^(-1)^(13)C_(6)-氯硝柳胺水合物标准溶液0.2 m L和含2.0%(体积分数)氨水的乙腈溶...为简化前处理过程,降低方法的检出限,进行了题示研究。采集鱼塘底泥样品,混匀、缩分、冷冻干燥、除杂、研磨、过筛后混匀,分取5.00 g,加入10.0μg·L^(-1)^(13)C_(6)-氯硝柳胺水合物标准溶液0.2 m L和含2.0%(体积分数)氨水的乙腈溶液20 m L,涡旋1 min,超声10 min,离心8 min。上清液于45℃旋蒸至近干,加入2.00 m L 70%(体积分数)乙腈溶液涡旋溶解残留物,再加入200 mg C18涡旋振荡30 s,离心5 min。收集上清液,过0.22μm有机滤膜,滤液采用高效液相色谱-串联质谱法测定。在色谱分析中,以Waters Atiantis^(TM) d C_(18)色谱柱为固定相,水-乙腈体系为流动相进行梯度洗脱;在质谱分析中,以电喷雾离子源负离子(ESI-)模式电离,选择反应监测(SRM)模式检测,内标法定量。结果显示,氯硝柳胺的质量浓度在0.20~50.00μg·L^(-1)内和其定量离子峰面积与同位素内标定量离子峰面积的比值呈线性关系,检出限(3S/N)为0.2μg·kg^(-1)。按照标准加入法进行回收试验,回收率为92.1%~113%,测定值的相对标准偏差(n=6)为1.6%~5.9%。方法用于实际样品的分析,检出的氯硝柳胺的质量分数为0.580~2.18 mg·kg^(-1)。展开更多
文摘LiNi_(0.5)Mn_(1.5)O_4(LNMO) was prepared by a high-temperature solid phase method,and then Al PO_(4)(AP) was coated on the polyhedral LNMO surface by the wet chemical method.The experimental results showed that the LNMO-1%AP|Li cell prepared with a 1%mass ratio of Al PO_(4and) LNMO had better electrochemical performance;after 450 cycles at 1C,its discharge specific capacity maintained 108.78 m Ah·g^(-1),while that of the LNMO|Li cell was only 86.04 m Ah·g^(-1).Especially at the high rates of 5C and 10C,the electrochemical properties of the former were far superior to the latter.This was attributed to the fact that the AP coating made the surface of LNMO in contact with the electrolyte more stable,effectively promoted the Li~+transport,and reduced the polarization voltage of the electrode.
文摘为简化前处理过程,降低方法的检出限,进行了题示研究。采集鱼塘底泥样品,混匀、缩分、冷冻干燥、除杂、研磨、过筛后混匀,分取5.00 g,加入10.0μg·L^(-1)^(13)C_(6)-氯硝柳胺水合物标准溶液0.2 m L和含2.0%(体积分数)氨水的乙腈溶液20 m L,涡旋1 min,超声10 min,离心8 min。上清液于45℃旋蒸至近干,加入2.00 m L 70%(体积分数)乙腈溶液涡旋溶解残留物,再加入200 mg C18涡旋振荡30 s,离心5 min。收集上清液,过0.22μm有机滤膜,滤液采用高效液相色谱-串联质谱法测定。在色谱分析中,以Waters Atiantis^(TM) d C_(18)色谱柱为固定相,水-乙腈体系为流动相进行梯度洗脱;在质谱分析中,以电喷雾离子源负离子(ESI-)模式电离,选择反应监测(SRM)模式检测,内标法定量。结果显示,氯硝柳胺的质量浓度在0.20~50.00μg·L^(-1)内和其定量离子峰面积与同位素内标定量离子峰面积的比值呈线性关系,检出限(3S/N)为0.2μg·kg^(-1)。按照标准加入法进行回收试验,回收率为92.1%~113%,测定值的相对标准偏差(n=6)为1.6%~5.9%。方法用于实际样品的分析,检出的氯硝柳胺的质量分数为0.580~2.18 mg·kg^(-1)。
