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71.
利用强短脉冲供电电源和一种新型的辉光放电灯联用进行阴极表面溅射,发现它与在直流供电下有不同的结果,扫描电镜进行观察,得到样品溅射表面的扫描图,结果表明,该技术的金属或合金样品表面的逐层分析提供了一种新方法。 相似文献
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A novel glucose biosensor has been fabricated and employed as the amperometric detector of a capillary electrophoresis (CE) system. (±)-1-Ferrocenylethylamine and chitosan were successively modified on a 500-µm diameter disc platinum electrode by dip-coating. The modified electrode was subsequently immersed in glucose oxidase (GOx) solution to entrap the enzyme in the chitosan membrane. The primary amino groups of 1-ferrocenylethylamine, GOx, and chitosan were cross-linked by glutaraldehyde to obtain a biosensing membrane so as to reduce leaching of 1-ferrocenylethylamine and GOx. The electrochemical behavior of the target biosensor was investigated. It was demonstrated that the investigated biosensor features fast response, high stability, long lifetime, and ideal compatibility with the CE system. When CE was employed to introduce a glucose plug into the surface of the biosensor, the current response was linear to the glucose concentration in the range of 0.0025 to 2.5 mM with a detection limit of 1.2 µM (S/N = 3) at a working potential of +0.6 V (vs. SCE). The CE-biosensor system was applied to the determination of the glucose level in human serum. The results were satisfactory and in good agreement with the hospital assay results. 相似文献
74.
茶水中多元素化学形态的同时分析 总被引:23,自引:0,他引:23
本工作建立了分离和测定茶水中Al、Mn、Mg、Zn及Fe的化学形态的方法。茶水中金属元素的各化学形态经高效液相色谱分离后,用电感耦合等离子体原子发射光谱在线检测Mn、Mg、Zn、Fe,用石墨炉原子吸收非在线测定Al。结果表明,茶水中Al等金属元素一部分以无机离子形式存在,另一部分则以有机络合物形式存在。实验发现当以Al、Mn、Mg、Zn、Fe儿茶素络合物作为标准物质时,HPLC的保留时间恰好与茶水 相似文献
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Pengyuan Zou Fan Yang Huaying Liu Hua Zhang 《Surface and interface analysis : SIA》2023,55(2):127-137
Resin-based carbon fibre reinforced composite (CFRP) with excellent properties has been widely applied in aerospace industry. In this study, polyether ether ketone enforced composite (PEEK-CFRP) and Ti-6V-4V titanium alloy had been joined by laser welding process. Micro-arc oxidation (MAO) process was conducted on the surface of titanium alloy to improve the joint property. Fractures and mechanical properties of joints were analysed. Interfacial microstructures of the joints had been investigated, and the formation mechanism of joint had been figured out. The results showed that after MAO treatment, the joint strength had been greatly improved and the shear strength reached to 42.3 MPa compared with pretreated sample. The wettability of CFRP on titanium alloy was rising with the contact angle of 68.8°. Fracture showed that cohesive failure contributed to the main fracture mode. As joints were formed by both mechanical bonding and chemical bonding, ‘anchor-shaped’ structures were found in the joint to enhance the mechanical bonding effects due to the flowing of the melted resin. (−OH) bonds were identified at the surface of MAO-treated titanium alloy that provided conditions for hydrogen bond interaction. TiO2, TiO and Ti–V–C phase were found at interface, whereas Ti–F and Ti–O–F bonds were generated during the welding process, which made great contribution to the chemical bonds between titanium alloy and CFRP. 相似文献
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We present a comprehensive method for proteome analysis that integrates both intact protein separation and proteolytic fragment characterization mass spectrometric approaches. Strong cation exchange chromatography (SCX) was used as the first separation dimension and capillary reversed-phase liquid chromatography (cRPLC) was integrated as the second separation dimension. Fractions from SCX were collected offline and loaded onto cRPLC. Effluents from cRPLC were directly deposited onto the MALDI target plates and further digested by using a rapid on-probe tryptic digestion technique. This approach minimizes the amount of time and extensive labor required for traditional in-solution digestion followed by exhaustive sample cleanup and transfer. MALDI-TOF/TOF was used for subsequent analyses. The sensitivity of on-target digestion is showed by analyzing 0.07 ng of myoglobin, 0.07 ng of cytochrome c and 0.7 ng BSA. The high efficiency of the overall system was demonstrated by the analysis of intact proteins extracted from normal human liver tissue. In total, 458 proteins were identified, which proved the system's promising potential for analysis and application in proteomics. 相似文献
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高妍琦 季来林 崔勇 饶大幸 赵晓晖 冯伟 夏兰 刘栋 王韬 史海涛 李福建 刘佳 杜鹏远 李小莉 刘佳妮 张天雄 单翀 马伟新 隋展 傅思祖 《强激光与粒子束》2020,32(1):011004-1-011004-2
激光等离子体相互作用的不稳定性将有望通过降低高功率激光装置输出光束的相干性得到大幅缓解。利用低相干光源作为种子源,采用钕玻璃放大介质,研制成功国际首台kJ级大带宽低相干激光装置,实现了带宽13 nm、能量960 J、脉宽3~10 ns可调,相干时间仅为300 fs的大能量光脉冲输出。输出脉冲光谱匀滑无纵模结构,且谱相位随机分布,可实现脉冲波形和光谱分布的无关联精密调控。该装置不仅成功演示验证了低相干激光驱动器的单元技术及系统集成技术,同时也为激光等离子体相互作用及高能量密度物理研究提供了全新的实验研究平台。 相似文献