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溴酸钾-亚甲蓝催化光度法测定硝酸盐和亚硝酸盐 总被引:15,自引:1,他引:15
用镉柱将NO-3 还原为NO-2 ,利用在磷酸介质中NO-2 对溴酸钾氧化亚甲蓝这一褪色反应具有强烈的催化作用而建立了同时测定痕量硝酸盐和亚硝酸盐的新方法。本方法简便、快速、灵敏 ,对亚硝酸盐和硝酸盐测定的线性范围分别为 0~ 2 0 0 μg·L-1和 0 0 0 3~ 310 μg·L-1,用于测定各种水样中痕量NO-2 和NO-3 的含量均获得满意结果 相似文献
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Hengyang Cheng Jinku Meng Guan Wu Su Chen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(48):17626-17634
Advanced methods, allowing the controllable synthesis of ordered structural nanomaterials with favourable charges transfer and storage, are highly important to achieve ideal supercapacitors with high energy density. Herein, we report a microliter droplet‐based method to synthesize hierarchical‐structured metal–organic framework/graphene/carbon nanotubes hybrids. The confined ultra‐small‐volume reaction, give well‐defined hybrids with a large specific‐surface‐area (1206 m2 g?1), abundant ionic‐channels (narrow pore of 0.86 nm), and nitrogen active‐sites (10.63 %), resulting in high pore‐size utilization (97.9 %) and redox‐activity (32.3 %). We also propose a scalable microfluidic‐blow‐spinning method to consecutively generate nanofibre‐based flexible supercapacitor electrodes with striking flexibility and mechanical strength. The supercapacitors display large volumetric energy density (147.5 mWh cm?3), high specific capacitance (472 F cm?3) and stably deformable energy‐supply. 相似文献
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Hui Qiu Hengyang Cheng Jinku Meng Guan Wu Su Chen 《Angewandte Chemie (International ed. in English)》2020,59(20):7934-7943
Chemical architectures with an ordered porous backbone and high charge transfer are significant for fiber‐shaped supercapacitors (FSCs). However, owing to the sluggish ion kinetic diffusion and storage in compacted fibers, achieving high energy density remains a challenge. An innovative magnetothermal microfluidic method is now proposed to design hierarchical carbon polyhedrons/holey graphene (CP/HG) core–shell microfibers. Owing to highly magnetothermal etching and microfluidic reactions, the CP/HG fibers maintain an open inner‐linked ionic pathway, large specific surface area, and moderate nitrogen active site, facilitating more rapid ionic dynamic transportation and accommodation. The CP/HG FSCs show an ultrahigh energy density (335.8 μWh cm?2) and large areal capacitance (2760 mF cm?2). A self‐powered endurance application with the integration of chip‐based FSCs is designed to profoundly drive the durable motions of an electric car and walking robot. 相似文献
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Hui Qiu Hengyang Cheng Jinku Meng Prof. Guan Wu Prof. Su Chen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(20):8008-8017
Chemical architectures with an ordered porous backbone and high charge transfer are significant for fiber-shaped supercapacitors (FSCs). However, owing to the sluggish ion kinetic diffusion and storage in compacted fibers, achieving high energy density remains a challenge. An innovative magnetothermal microfluidic method is now proposed to design hierarchical carbon polyhedrons/holey graphene (CP/HG) core–shell microfibers. Owing to highly magnetothermal etching and microfluidic reactions, the CP/HG fibers maintain an open inner-linked ionic pathway, large specific surface area, and moderate nitrogen active site, facilitating more rapid ionic dynamic transportation and accommodation. The CP/HG FSCs show an ultrahigh energy density (335.8 μWh cm−2) and large areal capacitance (2760 mF cm−2). A self-powered endurance application with the integration of chip-based FSCs is designed to profoundly drive the durable motions of an electric car and walking robot. 相似文献
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Apecytochrome b5 with a typical heme-binding motif of HPGC,and its variants with mutated motifs,GPGG,GPGH,HVGG,and HPGP,have been subjected to molecular dynamics simulation.Comparison of the dynamic consequences has revealed the crucial role of HPGG in assembling the heme group of cytochrome b5 and in modulating protein structure,property and function. 相似文献
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研究了壳聚糖-聚乙烯基恶唑啉半互穿聚合物网络膜对PH值的敏感性,发现该膜在PH〈6时溶胀度迅速增加,在PH=3.2时达到最大值;膜在不同PH值溶液中可交替溶胀收缩,且这种溶胀-收缩行为重复可逆。 相似文献
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中草药绞股蓝的傅里叶变换红外和拉曼光谱分析 总被引:4,自引:2,他引:4
利用傅里叶变换红外和拉曼光谱法直接、快速地测定了中草药绞股蓝样品 ,并对所测样品的红外、拉曼光谱图进行比较。结果表明 ,红外光谱图中各吸收峰位置与拉曼光谱图中各散射特征峰位置相对应 ,其关系互补。采用傅里叶变换红外和拉曼光谱分析法 ,对中草药绞股蓝的成份研究和特征波谱的鉴别 ,能为合理利用绞股蓝资源和寻找绞股蓝新的有效成分提供依据 相似文献
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