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将等离子体作为磁流体,考虑其流体属性和电磁属性,介绍了利用FLUENT软件包并将其进行二次开发,解算电磁场方程、质量连续性方程、动量守恒方程、以及能量守恒方程的数值模拟方法,得到了以磁矢势为表达形式的电磁场分布、温度分布和速度分布.数值模拟了粉末球化所用的感应耦合等离子体炬电磁场分布、温度分布、速度分布.分析了温度分布、速度分布产生的物理原因,为感应耦合等离子体炬球化粉末颗粒提供理论性指导.     

Cadmium (II) imprinted 3-mercaptopropyltrimethoxysilane coated stir bar for selective extraction of trace cadmium from environmental water samples followed by inductively coupled plasma mass spectrometry detection

Cd(II) imprinted 3-mercaptopropyltrimethoxysilane (MPTS)-silica coated stir bar was prepared by sol–gel technique combining with a double-imprinting concept for the first time and was employed for stir bar sorptive extraction (SBSE) of trace Cd(II) from water samples followed by inductively coupled plasma mass spectrometry (ICP-MS) detection. A tetramethoxysilane (TMOS) coating was first in situ created on the glass bar surface. Afterward, a sol solution containing MPTS as the functional precursor, ethanol as the solvent and both Cd(II) and surfactant micelles (cetyltrimethylammonium bromide, CTAB) as the template was again coated on the TMOS bar. The structures of the stir bar coating were characterized by FT-IR spectroscopy. Round-bottom vial was used for the extraction of Cd(II) by SBSE to avoid abrasion of stir bar coatings. The factors affecting the extraction of Cd(II) by SBSE such as pH, stirring rate and time, sample/elution volume and interfering ions have been investigated in detail, and the optimized experimental parameters were obtained. Under the optimized conditions, the adsorption capacities of non-imprinted and imprinted coating stir bars were found to be 0.5 μg and 0.8 μg bar⁻¹. The detection limit (3σ) based on three times standard deviations of the method blanks by 7 replicates was 4.40 ng L⁻¹ and the relative standard deviation (RSD) was 3.38% (c = 1 μg L⁻¹, n = 7). The proposed method was successfully applied for the analysis of trace Cd(II) in rain water, East Lake and Yangtze River water. To validate the proposed method, certified reference material of GSBZ 50009-88 environmental water was analyzed and the determined value is in a good agreement with the certified value. The developed method is rapid, selective, sensitive and applicable for the analysis of trace Cd(II) in environmental water samples.     

High-throughput quantification of palladium in water samples by ion pair based-surfactant assisted microextraction

A novel method for the determination of palladium as a metal ion model was developed by ion pair based surfactant-assisted microextraction (IP-SAME) and inductively coupled plasma-optical detection (ICP-OES). In this methodology, a cationic surfactant was used in extraction process. It has two fundamental functions: (1) the formation of an emulsified phase and (2) the ion pair formation with Pd(II) in the presence of iodide ions and making PdI₄²⁻$\text{Pd}{{\text{I}}_4}^{2-}$ extractable into organic phase (active microextraction). The effective parameters on the extraction recovery such as the types of extraction solvent and the surfactant, surfactant concentration, KI amount and HCl concentration of the sample were investigated and optimized. In the proposed approach, tetradecyl trimethyl ammonium bromide (TTAB) was used as emulsifier and ion pairing agent, and 1-octanol was selected as extraction solvent. Under the optimum conditions, the enhancement factor as large as 146 was obtained. The detection limit for palladium was 0.2 μg L⁻¹, and the relative standard deviation (RSD) was 4.1% (n = 5, C = 10.0 μg L⁻¹). The proposed method was applied for extraction and determination of palladium in different water samples.     

Elemental labelling combined with liquid chromatography inductively coupled plasma mass spectrometry for quantification of biomolecules: A review

This article reviews novel quantification concepts where elemental labelling is combined with flow injection inductively coupled plasma mass spectrometry (FI-ICP-MS) or liquid chromatography inductively coupled plasma mass spectrometry (LC–ICP-MS), and employed for quantification of biomolecules such as proteins, peptides and related molecules in challenging sample matrices. In the first sections an overview on general aspects of biomolecule quantification, as well as of labelling will be presented emphasizing the potential, which lies in such methodological approaches. In this context, ICP-MS as detector provides high sensitivity, selectivity and robustness in biological samples and offers the capability for multiplexing and isotope dilution mass spectrometry (IDMS). Fundamental methodology of elemental labelling will be highlighted and analytical, as well as biomedical applications will be presented. A special focus will lie on established applications underlining benefits and bottlenecks of such approaches for the implementation in real life analysis. Key research made in this field will be summarized and a perspective for future developments including sophisticated and innovative applications will given.     

三环无源谐振腔在光纤激光器中的选频特性

利用琼斯矩阵对一种三环嵌套的无源谐振腔的选频特性进行了分析,并根据无源谐振腔选频的原理,设计了一种基于三环嵌套无源谐振腔的掺铒光纤激光器。实验结果表明:三环嵌套的无源谐振腔具有良好的选频特性,当泵浦功率为159 mW时,得到了稳定的单纵模激光信号输出;输出功率的最大波动为0.04 dB,输出中心波长最大漂移为0.016 nm;耦合器的耦合比减小时,激光器会处于多纵模振荡状态。     

Speciation of Cr (III) and Cr (VI) via Reversed Phase HPLC with Inductively Coupled Plasma Emission Spectroscopic Detection (HPLC-ICP)24

Abstract

Chromium ions, viz., chromic (Cr^±3=III) and chromate (Cr^±6 = VI), can be reliably, conveniently, reproducibly, and quickly separated and detected by the use of conventional paired-ion, reversed phase (RP) high performance liquid chromatography (HPLC) together with refractive index (RI) and/or inductively coupled plasma emission spectroscopic (ICP) detection. A number of novel paired-ion approaches have now been developed, using PIC A (tetrabutylammonium hydroxide) or PIC B (sodium n-alkyl sulfonate) separately in the mobile phase. This allows for the retention of each Cr species depending on the particular ion pairing reagent being used, while the remaining Cr ion elutes in the solvent front. Changing the ion pairing reagent reverses the overall situation. The total time for each HPLC analysis is about 10 mins. ICP detection provides for a complete, overall method of speciation for both Cr (III) and Cr (VI) via two separate injections, together with quantitation for both species. This method of using paired-ion RP-HPLC can easily be applied to other mixtures of inorganic cations and anions, presumably with equally successful results. Minimum limits of detection are computed for chromate via direct-ICP, using at least two basic methods for such computations. It is suggested that virtually all chromatographic detection limits can be significantly improved by the application of newer, spectroscopic based methods of automated computation of detection limits.     

Rapid Speciation of Lead in Water by High-Performance Liquid Chromatography–Inductively Coupled Plasma Mass Spectrometry

The rapid speciation of lead is reported by high performance liquid chromatography and inductively coupled plasma – mass spectrometry. The separation of inorganic lead, trimethyllead, triethyllead and triphenyllead was achieved within 3.5 minutes on a C₁₈ column using a gradient program of methanol and water containing 5 milligrams per liter sodium 1-pentanesulfonate at pH 5. The limits of detection for inorganic lead, trimethyllead, triethyllead, and triphenyllead were 0.01, 0.02, 0.02, and 0.02 micrograms per liter, respectively. The accuracy of the method was verified by the analysis of water (GSBZ 50009-88) and seawater (GBW (E) 080040) certified reference materials. The method was also employed for the analysis of water samples; inorganic lead was measured in river water.     

Dispersive Liquid–Liquid Microextraction and Micro-Solid Phase Extraction for the Rapid Determination of Metals in Food and Environmental Waters

A rapid and novel two-step dispersive liquid–liquid microextraction and dispersive micro-solid phase extraction method was established for the separation and enrichment of trace cadmium, nickel, and copper in food and environmental water prior to determination by inductively coupled plasma-mass spectrometry (ICP-MS). In the first microextraction step, carbon tetrachloride was employed to extract metal-diethyldithiocarbamate chelates from aqueous solution with ultrasound. In the following step, Fe₃O₄ magnetic nanoparticles were added and used to collect the analytes in the organic solvent. The sample pH, type and volume of extraction solvent, mass of magnetic nanoparticles, concentration of the chelating agent, concentration of sodium chloride, and sonication time were optimized. The linear dynamic range was from 0.01 to 20 micrograms per liter with correlation coefficients between 0.9990 and 0.9992. Enrichment factors were 78, 79, and 81 for cadmium, nickel, and copper, respectively. The limits of detection for cadmium, nickel, and copper were 0.007, 0.009, and 0.017 micrograms per liter, with relative standard deviations from 1.1 to 2.6 percent. The developed method was validated by the determination of cadmium, nickel, and copper in rice and mussel certified reference materials, food, and environmental water with satisfactory results.     

Determination of Rare Earth Elements in Garnet Minerals,Geological Materials by Inductively Coupled Plasma–Atomic Emission Spectral and Mass Spectral Analysis

Abstract

The performance of inductively coupled plasma–atomic emission spectrometry (ICP‐AES) for the determination of 14 lanthanides and Yttrium was evaluated by comparison with inductively coupled plasma–mass spectral (ICP‐MS) analysis. The geochemical reference samples (GRS), DNC‐1(diabase), AGV‐1(andesite), Sy‐2(syenite), MRG‐1(gabbro), AN‐G(anorthosite), AC‐E(granite), and MAG‐1(marine mud) were chosen as test materials and analyzed for checking the precision and reproducibility of the methods. The mineral garnet is separated from the black sands of the southwest coast of India, and the combined cation exchange–ICP method of AES analysis and MS analysis were carried out for the determination of rare earth elements. Both techniques are within the requirements needed for garnet minerals. The determination of rare‐earth elements in these minerals, which contain other elements as major contribution and trace distribution of rare‐earth elements, shows that ICP applied under the proper working condition lives up to the expectations. Major element analysis gives the formula of garnet of Manavalakurichi (MK) as (FeCaMg)_2.79Al_2.07Si_3.05O₁₂ approximated to Fe₃Al₂Si₃O₁₂, hence of almandine-type garnet. The enrichment of heavy lanthanides compared to the light lanthanides indicates that these lanthanides occupy the coordinaton site of Fe²⁺ by replacement. Both techniques are excellent in determining the very low concentration of lanthanides in geological materials, specifically garnet.     

Determination of Lead in Lipstick by Direct Solid Sampling High-Resolution Continuum Source Graphite Furnace Atomic Absorption Spectrometry: Comparison of Two Digestion Methods

A new analytical procedure for the determination of lead in lipstick has been developed using direct solid sampling high resolution continuum source graphite furnace atomic absorption spectrometry (SS HR CS GFAAS). The performance of this method has been compared to acid digestion methods for sample preparation, with or without hydrofluoric acid (HF) with inductively coupled plasma mass spectrometry (ICP-MS) detection. Good reliability was obtained for all three methods; the results obtained for certified reference materials with concentrations between 1 and 20 ppm were in agreement with the certified values. However, for materials with complex matrices, such as pearl or Ca-Na borosilicate, only ICP-MS with HF sample digestion or AAS with direct solid sampling allowed complete recovery of lead. To avoid the use of hazardous acids, the development of SS HR CS GFAAS is an interesting alternative. With the AAS method, a characteristic mass of 13.2 pg of lead was obtained, and the limit of detection was 0.005 µg/g. The performance of the method was evaluated by determining lead in lipstick. The use of the solid sampling technique constitutes a good alternative for accurate and rapid determination of lead content in lipstick and cosmetic raw materials, with a suitable limit of detection and a reduced risk of contamination or of analyte loss. Another alternative would be to use ICP-MS determination in conjunction with microwave-assisted acid digestion without the use of HF, which implies accepting a quantification of “nearly total” lead, closer to a “bio-extractible” fraction.