HPLC-ELSD法测定化学药物成盐离子含量准确性的影响因素探讨

目的：探讨用混合模式离子交换柱建立HPLC-ELSD法测定化学药物成盐离子含量准确性的影响因素。方法：采用新型混合模式离子交换柱Acclaim Trinity P1（3.0 mm×100 mm,5μm）,以30 mmol·L-1醋酸铵缓冲液（取醋酸铵4.59 g,加水1900 mL使溶解,用冰醋酸调节pH至5.2,加入乙腈100 mL）-乙腈（50∶50,v/v）为流动相,流速0.3 mL·min-1,柱温25℃;以蒸发光散射检测器检测,漂移管温度90℃,氮气作为载气,流速2.6 L·min-1。建立HPLC-ELSD法测定奥美拉唑钠中钠离子含量并进行方法学验证;同时选择奥美拉唑钠、头孢曲松钠、盐酸博宁霉素,分别代表药物分子在色谱过程中不保留、强保留和不洗脱3种状态,进行准确度、精密度试验,以数据统计软件SPSS 19.0进行统计分析,考察药物分子洗脱状态对成盐离子含量准确性（准确度、精密度）的影响。结果：钠离子浓度在1.94-77.48μg·mL-1范围内与峰面积呈二项式相关关系（r=0.9999）;加样回收率（n=3）分别为104.5%、101.7%、102.6%,RSD分别为1.3%、3.7%、2.2%;奥美拉唑钠中钠离子平均含量（n=8）为6.23%,与理论钠离子含量（6.24%）无显著性差异（t-检验,α=0.05）;药物分子洗脱状态对钠离子测定的中间精密度、重复性结果以及氯离子测定的重复性有影响（ANOVA分析,α=0.05）,药物分子很难洗脱以及不洗脱将导致精密度偏低。结论：采用新型混合模式离子交换柱,用HPLC-ELSD法测定化学药物中成盐离子含量时,方法通用性好,专属性强,线性范围宽,耐用性好,但药物分子很难洗脱或者不洗脱在色谱填料上将导致精密度偏低。

The potassium storage performance of carbon nanosheets derived from heavy oils

As by-products of petroleum refining,heavy oils are characterized by a high carbon content,low cost and great variability,making them competitive precursors for the anodes of potassium ion batteries(PIBs).However,the relationship between heavy oil composition and potassium storage performance remains unclear.Using heavy oils containing distinct chemical groups as the carbon source,namely fluid catalytic cracking slurry(FCCS),petroleum asphalt(PA)and deoiled asphalt(DOA),three carbon nanosheets(CNS)were prepared through a molten salt method,and used as the anodes for PIBs.The composition of the heavy oil determines the lamellar thicknesses,sp3-C/sp2-C ratio and defect concentration,thereby affecting the potassium storage performance.The high content of aromatic hydrocarbons and moderate amount of heavy component moieties in FCCS produce carbon nanosheets(CNS-FCCS)that have a smaller layer thickness,larger interlayer spacing(0.372 nm),and increased number of folds than in CNS derived from the other three precursors.These features give it faster charge/ion transfer,more potassium storage sites and better reaction kinetics.CNS-FCCS has a remarkable K^(+)storage capacity(248.7 mAh g^(-1) after 100 cycles at 0.1 A g^(-1)),long cycle lifespan(190.8 mAh g^(-1) after 800 cycles at 1.0 A g^(-1))and excellent rate capability,ranking it among the best materials for this application.This work sheds light on the influence of heavy oil composition on carbon structure and electrochemical performance,and provides guidance for the design and development of advanced heavy oil-derived carbon electrodes for PIBs.

康地宝的试验示范应用

昌吉市老龙河农业高新技术开发区新开垦土地都不同程度地存在盐渍化.……

Tetraalkylammonium Fluorosilicates as Precursors for Electrochemical Deposition of Silicon Coatings. Synthesis and Thermal Stability

Several TAAFS （tetraalkylammonium hexafluorosilicates） with different cations were synthesized. Their thermal properties were studied showing that obtained complexes are stable enough to be suitable for electrochemical deposition of silicon coatings under temperatures at least up to 200 ℃.