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电渗泵在顺序注射萃取法测定酚中的应用 总被引:4,自引:0,他引:4
电渗泵是一种液流驱动泵,具有装置简单、载流无脉动、流量范围大和驱动电压适中等优点。用含1mmol/L三乙醇胺和0.1mmol/L四丁基溴化铵的乙醇溶液作泵载流,采用顺序注射萃取-分光光度法,对水样挥发酚进行了测定。有机载流可避免产生界面,减小检测干扰。载流添加剂可提高泵流量,改善流量稳定性。另外,还研究了酚的各种萃取条件。水中酚的检出限为7цg/L(3a,n=11);回收率为92%-94%。方法证明了电动流动分析系统可用于溶剂萃取和有机分析。 相似文献
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电渗泵在微柱液相上的应用 总被引:6,自引:0,他引:6
设计评价了一种能够取代机械泵的电渗泵 (EOP) ,该泵可以产生 2 0MPa~ 6 0MPa的输出压力和几十nL/min~ 3μL/min的输出流量 ;用乙腈 水作为流动相 ,在 14cm× 32 0 μmi d (C18,5 μm )微柱上分离了萘、蒽、菲3种物质的混合试样 ,证明EOP在微柱液相领域有广阔的应用前景。 相似文献
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设计了一种小型低压电渗泵。该泵主要由直流电源、填充电渗柱、铂电极和压力传感器等构成。电渗柱的内部尺寸为6×12 mm,柱内填充45μm的多孔硅胶。工作时,泵头直接浸入被输送的液体中进行输液。研究了电压和电流对输出压强和流量的影响:压强和电压及电流均成良好的线性;而在250 V以上,流量增加变快,明显偏离线性。对去离子水和0.5 mmol/L的KC l溶液,该泵可产生0~1.6 atm的输出压力和每分钟几μL至几百μL的输出流量。该泵结构简单,可以不间断输液一星期以上,能用于微流控分析、流动注射分析及微反应输液等领域。 相似文献
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单级高压微流量电渗泵的研究 总被引:1,自引:0,他引:1
设计了一种高压微流量电渗泵。泵体主要由高压电源、电渗柱、毛细通道、导电空心电极以及气泡去除器、压力传感器等构成。单级电渗泵可以给出0~20MPa范围的输出压力和nL~μL级输出流量。输出压强和输出流量取决于电压、填充柱阻力和流体性质。 相似文献
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采用电动流动分析(EFA)和胶束电动毛细管色谱(MEKC)联用系统测定了食品中的防腐剂.EFA系统设备简单便携、易于实现自动化.EFA由一台自制电渗泵、5个电磁切换阀(由计算机通过自制接口卡和自编VC语言程序控制)和一个固相萃取微柱组成,采用EFA-MEKC低试剂消耗接口,可减少含贵重试剂的缓冲液消耗.MEKC缓冲溶液为100 mmol/L十二烷基硫酸钠(SDS) 20 mmol/L Na2B4O7(pH 9.3).使用对羟基苯甲酸(PBA)为内标物,方法可在15 min内分离测定6种防腐剂,峰面积相对标准偏差小于3.4%;检出限范围为0.04~0.1 mg/L;实际样品的回收率为91.4%~104%. 相似文献
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A porous core electroosmosis pump was studied and improved in accordance with the electroosmosis theory. Hexamethylene tetraamine (HMTA) was used as the additive of pump carrier solution to improve the flow rate stability and delivery efficiency. The influences of the electric field strength, porous core dimension and acetonitrile concentration of carrier solution on the pump flow rate and output pressure were investigated in detail. The improved electroosmosis pump can provide not only steady flow rate and large flow range, but also moderate output pressure. With the pump carrier solution of 0.5 mmol/L HMTA and the working voltage of 4950 V, the pump output pressure, flow rate and delivery efficiency achieved 1.1 MPa, 1.3 mL/min and 3.2 mL/(min mA), respectively. The pump can be employed for mobile phase delivery in the reversed-phase chromatographic separation of monolithic silica columns. 相似文献
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采用超临界CO2流体色谱技术,分析d4T-5’-N-磷酰化苯丙氨酸甲酯手性磷的非对映异构体。色谱柱为Hpersil ODS2(250 mm×4.6 mm,5μm),流动相为夹带改性剂甲醇、乙醇和异丙醇的超临界CO2流体。以容量因子、选择性和分离度为指标,考察改性剂、背压和柱温对分离的影响。在甲醇、乙醇和异丙醇3种改性剂中,甲醇为最好的改性剂,其中在7%甲醇改性剂下,该化合物的分离度可达到3.35。在7%甲醇改性剂条件下,考察了压力(10~20 MPa)和温度(303.15~318.15 K)的影响。在优化的分离条件(改性剂为7%甲醇,流速为2 mL/min,柱温为308.15 K,背压为15 M Pa)下,d4T-5’-N-磷酰化苯丙氨酸甲酯的两种非对映异构体完全达到基线分离,分离时间约15 min。 相似文献
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离子液体作高效液相色谱流动相添加剂分离测定芳香胺 总被引:3,自引:0,他引:3
建立了以离子液体作反相高效液相色谱流动相添加剂分离测定邻苯二胺、苯胺和对甲苯胺3种芳香胺的方法。实验以C18反相色谱柱为分离柱,采用紫外检测方法,考察了检测波长、甲醇含量、咪唑离子液体烷基链长度、离子液体溶液浓度等条件对分离和测定的影响,并与其它分离测定芳香胺的方法进行了比较。优化的色谱条件为:以甲醇/1-丁基-3-甲基咪唑四氟硼酸盐水溶液(3.0mmol/L,乙酸调节pH 3.5)=30/70(V/V)为流动相;检测波长254 nm;流速1.0mL/min;柱温30℃。在此条件下,3种芳香胺达到基线分离,在6.5 min之内分离完全;在1~40 mg/L范围内,线性回归方程的相关系数达到0.99以上;检出限为0.07~0.41 mg/L。将本方法应用于废水的测定,加标回收率在92.3%~96.7%之间,相对标准偏差小于3.5%。 相似文献
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将C18柱与手性冠醚柱串联,建立了一种反相高效液相色谱法用于3种芳香族氨基酸对映体同时拆分的方法.考察了反相色谱流动相的组成、pH值、柱温、流速对对映体拆分的影响.实验结果表明,当流动相为HClO4-乙睛溶液(86:14,V/V,pH 2.0)、柱温20℃、流速0.4 mL/min时,3种氨基酸对映体可获得基线分离.进一步对比了C18柱、冠醚手性柱和串联顺序不同的4种分离模式,结果表明,C18柱不能拆分氨基酸对映体,仅能分离不同种类氨基酸;冠醚手性柱可分离氨基酸映体,但不同种类氨基酸色谱峰出现重叠;串联模式能实现3种氨基酸对映体的基线分离,实现双柱优势互补,而串联顺序对分离影响不大,仅影响色谱峰的峰形. 相似文献
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An electroosmotic pump (EOP) capable of generating pressure above 3 MPa and μl/min flow rate with reverse phase mobile phases of HPLC was constructed and evaluated. The pump consisted of three parallel connected fused silica capillary columns (25 cm×320 μm I.D.) packed with 2 μm silica materials, hollow electrodes, a high voltage DC power supply, and a liquid pressure transducer. The EOP was applied in a capillary liquid chromatographic system for mobile phase delivery instead of a mechanical pump. Standard samples containing thiourea, naphthalene, anthracene, phenanthrene and acetonitrile were separated on a 15 cm×320 μm I.D. 5 μm Chromasil C18 packed capillary column with acetonitrile/water as mobile phase. 相似文献
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Evaluation of tertiary pyridine resin for the separation of lanthanides by simulated moving‐bed chromatography 下载免费PDF全文
Balamurali Sreedhar Tatsuya Suzuki David T. Hobbs Yoshiaki Kawajiri 《Journal of separation science》2014,37(20):2892-2899
Lanthanide separation by simulated moving‐bed chromatography was studied as a model system for separating lanthanide fission products and minor actinides from used nuclear fuels. The simulated moving‐bed system was modeled for a tertiary pyridine anion‐exchange resin supported on silica particles as the stationary phase and a mixture of methanol and 1M nitric acid as the mobile phase. Pulse injection tests using a single packed column were used to obtain chromatographic parameters for mathematical modeling of the simulated moving‐bed system. Higher concentrations of methanol improved the separation, but the chromatograms showed evidence of nonlinearity of the isotherms. The mathematical model of the simulated moving‐bed process predicted a production rate of purified samarium and neodymium at 118 g solute/L resin/day and a purity of 99.5%. The optimal methanol ratio for the production rate for various product purities was determined from the model. The excellent separation of Nd and Sm suggests that the simulated moving‐bed system could be applied to the separation of minor actinides such as americium and curium. 相似文献