复合乳液乳胶粒样品的制备

报道了利用火棉胶支持膜制取复合乳液乳胶粒样品的技术，不同于传统制作方法，其所其制备的样品具有分散度好，样品边界清晰等优点。     

Ultrasound assisted pseudo-digestion of street dust samples prior to determination by atomic absorption spectrometry

A sample preparation method based on ultrasound assisted pseudo-digestion of Pb, Cu, Zn and Ni from street dust samples under ultrasonic effect has been described. Parameters influencing pseudo-digestion, such as sonication time, sample mass, particle size and solvent system were fully optimized. Final solutions obtained upon sonication were analyzed by atomic absorption spectrometry. The best conditions for metal pseudo-digestion were as follows: a 25 min sonication time, a 0.3 g sample mass (in 25 ml solvent), a particle size <63 μm and a mixture of concentrated HNO₃-HClO₄-HF (2:1:1, v/v/v). Analytical results for the four metals by ultrasound assisted pseudo-digestion, acid bomb and conventional wet digestion methods showed a good agreement, thus indicating the possibility of using mild conditions for sample preparation instead of intensive treatments inherent with the digestion methods. In addition, this method reduces the time required for all treatments (pseudo-digestion or digestion, heating to dryness, cooling and separation) with acid bomb and conventional wet digestion methods approximately from 9 to 1 h. The accuracy of the method was tested either by comparing obtained results with those of acid bomb and conventional wet digestion methods or by application on two standard reference materials. The average relative standard deviation of ultrasound assisted pseudo-digestion method varied between 0.9 and 1.8% for N = 12, depending on the analyte.     

Comparison of extraction techniques of robenidine from poultry feed samples

In this paper, effectiveness of six different commonly applied extraction techniques for the determination of robenidine in poultry feed has been compared. The sample preparation techniques included shaking, Soxhlet, Soxtec, ultrasonically assisted extraction, microwave – assisted extraction and accelerated solvent extraction. Comparison of these techniques was done with respect to the recovery extraction, temperature and time, reproducibility and solvent consumption. Every single extract was subjected to clean – up using aluminium oxide column (Pasteur pipette filled with 1 g of aluminium oxide), from which robenidine was eluted with 10 ml of methanol. The eluate from the clean-up column was collected in a volumetric flask, and finally it was analysed by HPLC–DAD–MS. In general, all extraction techniques were capable of isolating of robenidine from poultry feed, but the recovery obtained using modern extraction techniques was higher than that obtained using conventional techniques.

In particular, accelerated solvent extraction was more superior to other techniques, which highlights the advantages of this sample preparation technique. However, in routine analysis, shaking and ultrasonically assisted extraction is still the preferred method for the solution of robenidine and other coccidiostatics.     

环境内分泌干扰物分析方法的研究与进展

本文对近5年来国内外环境内分泌干扰物的研究进展进行了综述，包括环境内分泌干扰物的分类、样品前处理技术、检测技术等，并对环境内分泌干扰物分析的发展进行了总结和展望，引用文献286篇。     

天然高分子吸附剂研究：Ⅰ.乙二醇双缩水甘油醚交联壳聚糖的制备及其对Cu（？

报道了乙二醇双缩水甘油醚改性壳聚糖的制备及其对Ｃｕ（Ⅱ）、Ｎｉ（Ⅱ）的吸附性能，同时考察了ＰＨ值、时间、温度等因素对吸附的影响。结果表明，改造后的壳聚糖具有不流失，易再生，在Ｃｕ（Ⅱ）、Ｎｉ（Ⅱ）共存时能选择吸附Ｃｕ（Ⅱ）的特点。     

样品带示踪法测定毛细管电泳过程中的电渗流

电渗流在毛细管区带电泳（CZE）和胶束电动力色谱（MEKC）中具有重要作用,通过控制电渗流可以提高分辨率或加快分析速度,因而控制和测定电渗流已成为毛细管电泳领域重要的研究课题．SalomonK．［'j建立了一种电渗流近似模型,但因影响因素复杂,电渗流还无法从理论上计算,只能通过实验测定．目前常用的测定法有中性示踪剂法［'－"、称量法［'和电泳电流监测法［'j本文提出一种新的电渗流测定法--样品带示踪法,该法不必另加示踪剂,利用样品带中的基体介质即可示踪电渗流．该法适用于较宽的I。H范围及多种检测器,对于某些样品（与…     

Preconcentration of triazine herbicides from water by an ion chromatography column and determination by gas chromatography-mass spectrometry

The efficiency of ion chromatography columns packed with styrene-divinylbenzene copolymer containing quaternary ammonium groups to preconcentrate triazine herbicides and their degradation products below μg/l levels has been established. Retention is studied for different types of water. Pure methanol was used in a one-step elution. Enrichment factors of at least 4000 are achieved. Determination was carried out by using gas chromatography-single-ion monitoring mass spectrometry. Recoveries for run-off agricultural water were between 67–100% and close to 100% for ground water. The maximum admissible concentration ion drinking water (0.1 μg/l) and the alert and alarm threshold values in surface water (1 and 3 μg/l, respectively) dictated by the European Union can be measured.     

混合表面活性剂体系聚苯乙烯/Fe3O4复合纳米粒子的制备

在TritonX-100/十二烷基苯磺酸钠混合表面活性剂体系中，制得核-壳型结构的聚苯乙烯/Fe₃O₄复合纳米粒子。通过X-射线衍射、傅立叶红外光谱测定表明，复合纳米粒子结构组成以Fe₃O₄为核_，聚苯乙烯为壳，证明聚苯乙烯在Fe₃O₄纳米粒子上的包覆是成功的。电子显微镜观察结果表明：Fe₃O₄纳米粒子的粒径约10 nm，聚苯乙烯/Fe₃O₄复合纳米粒子的粒径为25-35 nm。     

Preparation of polyaniline coating on a stainless-steel wire using electroplating and its application to the determination of six aromatic amines using headspace solid-phase microextraction

A novel polyaniline (PANI) coating was prepared on a stainless-steel wire for solid-phase microextraction by electroplating method. For better mechanical strength, the stainless-steel wire was used instead of the fused silica fiber. The electroplating method had advantages of ease of preparation and simple equipments. The PANI fiber was evaluated by analyzing six aromatic amines (aniline, N,N-dimethylaniline, m-methylaniline, 2,4-dimethylaniline, 2-chloroaniline, 3,4-dichloroaniline) in water. After the analytical procedure was optimized, the linearity was from 4.8 to 2.75 x 10(4) microg L(-1) and the detection limits was from 0.019 to 1.06 microg L(-1). Relative standard deviations were found to be 2.02-6.00%. Good recoveries were obtained when wastewater samples were analyzed.     

Efficient One-Pot Preparation of Methylthio Arylbutadiynes by Double Elimination Protocol

A novel and efficient method for preparation of methylthio arylbutadiynes (Ar-C≡C-C≡C-SCH₃) was described, and a series of compounds have been expediently obtained by the one-pot protocol starting from methylthiomethyl phenyl sulfone (MP-S) and arylpropargyl aldehydes. The mechanism was discussed on the basis of trapping and characterization of key intermediates. The results from experiments indicated that the reaction involved the initial nucleophilic addition of MP-S to arylpropargyl aldehydes to produce an intermediate carrying two leaving groups and subsequent double elimination reactions.

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