色谱法分离穿心莲中生理活性成分

本文用薄层色谱、柱色谱和高效液相色谱相结合的方法。对穿心莲地上部分的ＭｅＯＨ提取液的ＡｃＯＥｔ层进行了分离心莲中生理活性成分成功地分离出１０种化合物，其中有一种是结构待定的新化合物。     

色谱技术研究进展及应用

简要介绍了色谱技术的历史发展，对几种常见的色谱技术和近期发展起来的一些新型色谱技术的研究进展及应用进行了综述，阐述了不同特性色谱技术的发展方向。     

新型分离技术--工业高效制备色谱

工业高效制备色谱技术是一种新型、高效、节能的分离技术.介绍了模拟移动床色谱、VariCol色谱和超临界流体色谱3种主要的工业高效制备色谱的原理和应用,并扼要介绍了工业高效制备色谱分离过程的模拟和优化方法.     

连续制备色谱的研究进展

本文介绍了近30年来连续制备色谱分离的研究概况，从逆流和错流两个方面分别表述了半连续色谱精制器和连续环状色谱的基本原理，研究进展及应用前景。     

现代分离技术在药品分析中的应用研究进展

药品分离是现代技术研究的一个重点方面,介绍3种现代技术在药品分离中应用。气相色谱法以气体为流动相的色谱方法,是一种检测挥发性有机化合物的功能强大的分离技术,可以用于分离分析易挥发物质,作为重要的分离分析方法之一,已经成为药物含量测定的方法。高效液相色谱法是以液体为流动相,对复杂样品进行分离分析,在中药等复杂体系的成分分离中发挥极其重要的作用。毛细管电泳法通过电泳和分配行为差异实现分离,具有操作简单、分离效率高等优点。     

连续环状离子交换色谱分离技术

本文介绍了一种新型制备色谱分离技术──连续环状离子交换色谱ＣＡＣ，建立了二维稳定连续环状离子交换色谱的数学模型。在一定条件下经过适当转化，二维稳态ＣＡＣ过程可转化为一维非稳定色谱过程。分别改变ＣＡＣ进料浓度、进料流速及冲洗流速等操作条件，测定了ＣＡＣ对果葡糖的分离性能。同时，用固定床线性色谱理论对ＣＡＣ进行预测，其预测值与实验结果较好地相吻合。实验得出，连续环状离子交换色谱对果葡糖具有较好的分离性能。     

逆流色谱技术在手性分离方面的应用

逆流色谱是一种不用固态支撑体或载体的液液分配色谱技术,其分离原理具有手性制备性分离的优势。以近年采用逆流色谱技术对手性化合物分离的应用进行了综述。     

高速逆流色谱在分离纯化中草药黄酮类成分中的应用

高速逆流色谱(HSCCC)技术是国际上较新型的无需固态支撑体的液-液分配色谱技术.介绍了高速逆流色谱的原理、优点、溶剂体系的选择原则、方法,并对其在中草药黄酮类成分分离纯化制备方面的应用进行综述.     

甘露糖赤藓糖醇脂分离纯化条件的研究

甘露糖赤藓糖脂是由醇母产生的一种新型的非离子生物表面活性剂，采用柱色谱和薄层色谱对从发醇液中离心萃取得到的粗品进行了分离纯化，着重研究了硅胶粒径，洗脱剂种类和极性，洗脱速率以及洗脱剂用量等条件，并得到了最佳分离效果的条件组合。     

制备型高效液相色谱技术的研究进展

制备型高效液相色谱是一种快速,有效的分析分离工具.本文介绍了制备型高效液相色谱基础理论及基本装置,介绍了样品的预处理和应用实例,分析了目前制备型高效液相色谱技术存在的问题并对该技术未来的发展进行了展望.     

Competitive foam separation of rare earth elements from aqueous solutions using a cationic collector

ABSTRACT

Competitive foam separation of two rare earth elements (REEs), Eu(III) and Tb(III), are investigated in this study in presence of ethylenediaminetetraacetic acid (edta) using cetylpyridinium chloride (CPC). The effects of pH, [edta]/Σ[REEs] and [CPC]/[edta] molar ratio, frother concentration, ionic strength and air-flow rate on the foam separation efficiency are also evaluated. At the optimal experimental condition, Eu(III)/Tb(III) separation factor of 141.56 is obtained. The kinetic data obtained at all the studied parameters are analyzed by the flotation first-order and second-order kinetic models. Eventually, a schematic flow-sheet for Eu(III)/Tb(III) separation is proposed.     

头孢菌素C发酵液膜过滤的评价指标及其控制

发酵液的过滤澄清是头孢菌素C（CPC）分离与提纯的首要环节,对CPC产品的质量、成本和生产进度等有着很大的影响。本文针对CPC发酵液的膜过滤过程,分别给出了过滤过程评价指标和滤液质量评价指标。通过对部分评价指标的分析,讨论了影响各指标水平的具体因素,并建立起了有关参量间的量化模型,从而为滤液质量的控制与生产过程的优化提供了途径和方法。     

Interpretation of Volatility Tandem Differential Mobility Analyzer (V-TDMA) data for accurate vapor pressure and enthalpy measurement: Operational considerations,multiple charging,and introduction to a new analysis program (TAO)

Abstract

Significant evaporation of pure aerosols in a Volatility Tandem Differential Mobility Analyzer (V-TDMA) creates two Condensation Particle Counter (CPC) response peaks. Two hypotheses for the observed peaks have been proposed: the existence of two phases or the separation of the singly charged experimental size distribution from the remaining experimental size distributions with charges greater than 1 (charge separation). To explore this observation, we atomized pure levoglucosan aerosol and evaporated the aerosol until two peaks formed. We used an additional classifier and neutralizer to select particles from each of the two peaks and assessed the number of charges on the particles. The smaller diameter peak contained singly charged particles, and the larger diameter peak contained the remaining charges. The charge separation hypothesis alone accounts for the two-peak observations. We used a new V-TDMA model named TAO and show that charge separation should occur in other pure components as well. The TAO model was then used to display the impact of different DMA transfer functions, different inlet size distributions, and different oven residence time distributions (RTDs) on the CPC response. Large errors are possible when direct measurement of the RTD is not performed or when wide RTDs are used. We recommend use of narrow transfer functions with narrow RTDs to detect charge separation. When the singly charged CPC response is isolated (smaller diameter peak in the two peak response), accurate estimations of vapor pressure can be recovered, assuming accurate values for gas phase diffusivity, surface energy, particle density, etc. are used.

Copyright © 2020 American Association for Aerosol Research     

兽疫链球菌NW-162发酵产生的透明质酸分离纯化研究

对兽疫链球菌诱变株NW-162发酵液中透明质酸(HA)的分离提取工艺方法进行了对比研究。采用乙醇沉淀分离透明质酸、链霉蛋白酶酶解结合氯仿除去蛋白质及经氯代十六烷吡啶分级分离工艺,结果表明:乙醇与上清液的体积比为2.5∶1.0时沉淀透明质酸25 h最为经济;酶解结合氯仿去除蛋白质较氯仿单独作用时,透明质酸产量及纯度均有一定提高,再经氯代十六烷吡啶分级分离后,可得纯度为71.5%、蛋白质质量分数2.8%、产量0.747 g/L、相对分子质量725×103的透明质酸产品。     

利用活性炭分离去乙酰基头孢菌素C

利用粉状活性炭为吸附剂,处理头孢菌素C生产过程中的废弃液,实现了去乙酰头孢菌素C(DCPC)和头孢菌素C(CPC)及其他杂质的有效分离.以乙醇-水和异丙醇-水体系作为洗脱剂,得到纯度80%的DCPC溶液.乙醇-水体系收率可达75%,异丙醇-水体系收率可达80%.实验表明,15%乙醇-水和15%异丙醇-水体系分离效果较差;10%乙醇-水和10%异丙醇-水体系洗脱力较弱;12%～13%乙醇-水和12%～13%异丙醇-水体系的洗脱和分离效果较好;13%异丙醇-水体系优于13%乙醇-水体系.     

Recovery of surfactant from an aqueous solution using continuous multistage foam fractionation: Influence of design parameters

A multistage foam fractionation column with bubble cap trays was used to recover a surfactant from water at low concentrations. The effects of design parameters—including the number of bubble caps, foam height, and tray spacing—were first investigated under steady state conditions using cetylpyridinium chloride (CPC) as the model surfactant. An increase in bubble caps per tray significantly increased the separation efficiency, both in terms of the enrichment ratio and recovery of the CPC and of the separation factor (ratio of foamate concentration to effluent concentration). The increase in bubble caps per tray also increased the foam production rate, leading to increasing the adsorptive transport. An increase in tray spacing increased both the enrichment ratio and the residual factor of the CPC, whereas the CPC recovery and liquid entrainment in foam were reduced. An increase in foam height produces drier foams, leading to decreasing bulk liquid transport.     

Recovery of Surfactant from an Aqueous Solution Using Continuous Multistage Foam Fractionation: Mixed Surfactant System

A continuous multistage foam fractionation column with bubble caps was used for surfactant recovery from mixed surfactant solutions containing polyethylene glycol tert-octylphenyl (OPEO₁₀) and cetylpyridinium chloride (CPC) and the effects of air flow rate, foam height, and feed flow rate were investigated under a steady state of conditions. For the mixed surfactant system, the effect of synergism in the surfactant adsorption density was found. For separation efficiency, the total residual factor remained unchanged with an increasing feed molar fraction of OPEO₁₀ (α), suggesting that the addition of OPEO₁₀ does not increase the total separation efficiency. The residual factor of CPC increased with an increasing molar fraction of OPEO₁₀ (α), while the residual factor of OPEO₁₀ was lower for the mixed surfactant systems. A competitive removal was found in that the OPEO₁₀ can compete with CPC for the bubble surface. The total separation factors and enrichment ratio of mixed surfactant systems were in-between the two single surfactant systems at a long foam residence time and, in contrast, showed antagonism at short foam residence. This is due to the difference in liquid entrainment in foam at long and short foam residence times.     

SEPARATION OF PALLADIUM(II) FROM PLATINUM(II), IRIDIUM(III), AND RHODIUM(III) USING CENTRIFUGAL PARTITION CHROMATOGRAPHY

The separation of Pd(II) from Pt(II), Ir(III) and Rh(III) with trioctylphosphine oxide (TOPO) in heptane using centrifugal partition chromatography (CPC) has been investigated for the first time. The extraction of Pd(II) has been studied by CPC and batch solvent extraction. The distribution ratios for Pd(II) determined by both methods agree well. In low HCl concentrations (<0.1 M), the extracted species was PdCl₂.(TOPO)₂, irrespective of the chloride concentration, while at acid concentrations above 0.1 M, the Pd was extracted as the ion pair, 2(TOPO.H⁺).PdCl₄ ^2-. Base line separation of Pd(II) and Pt(II) in CPC was obtained under a variety of chloride and HCl concentration with the average number of theoretical plates being 390 ± 40 at a flow rate of 0.47 ± 0.05 mL/min.     

One Step Purification of Piperine Directly from Piper nigrum L. by High Performance Centrifugal Partition Chromatography

Abstract

In this study, a preparative high performance centrifugal partition chromatography (HPCPC) method for isolation and purification of the bioactive component piperine directly from the ethanol extract of Piper nigrum L. was successfully established by using n-hexane-ethyl acetate-methanol-water as the two-phase solvent system. The upper phase of n-hexane-ethyl acetate-methanol-water (6:5:6:5, v/v) was used as the stationary phase of CPC. Under the optimum conditions, 40 mg of piperine at 98.5% purity, as determined by HPLC, was yielded from 300 mg of the crude extract in a single CPC separation. The peak fraction of CPC was identified by ¹H NMR and ¹³C NMR.     

On Plate Identification of Coexisting Polyoxyethylene (20) Stearyl Ether,Cetyl Pyridinium Chloride,Tetradecyl Trimethyl Ammonium Bromide and Polyoxyethylene (9.5) Octyl Phenyl Ether Surfactants with Preliminary Separation by Planar Chromatography

Separation studies of four surfactants (nonionic and cationic) were performed on silica high-performance thin-layer chromatographic plates with various solvent systems. The most useful chromatographic system for the mutual separation of coexisting polyoxyethylene (20) stearyl ether (C18EO20), cetylpyridinium chloride (CPC), tetradecyl trimethyl ammonium bromide (TTAB) and polyoxyethylene (9.5), octyl phenyl ether (OPEO9.5) was formamide + 1 M formic acid (50:50 v/v). The nature of ‘H’ and ‘H⁺’ of formic acid (H–COO⁻H⁺) on the mobility of these surfactants was studied. The interference due to the presence of metal cations as impurities on the resolution of mixture of C18EO20, CPC, TTAB and OPEO9.5 was also examined. The limits of detection of C18EO20, CPC, TTAB and OPEO9.5 estimated were 0.0620, 0.0310, 0.0625 and 0.0312 μg/zone, respectively. The practical applicability of the proposed method was tested for the identification of four coexisting surfactants after their separation from the spiked aqueous systems.