Environmental applications for thermal analysis

A review is presented of the applications of thermoanalytical techniques to problems encountered in the measurement and control of air pollution. A number of suggestions are offered regarding new or extended applications of these techniques.     

Environmental and pharmaceutical analysis of dithiocarbamates

The current review aims at a comprehensive survey of analytical methods for the determination of dithiocarbamates (DTCs) in environmental and pharmaceutical samples. Besides parent compounds, analytical approaches for various metabolites and degradation products of DTCs are considered. Special emphasis is given to analyte stability as DTCs are considerably reactive interacting with various organic and inorganic compounds; in addition, depending on the chemical nature of the substance, DTCs are prone to oxidation and hydrolysis under alkaline and acidic conditions, respectively. The review mainly focuses on chromatography but also covers applications in electrophoresis, spectrophotometry, and biosensing.     

The teaching of problem solving: Environmental analysis

Summary An attempt is made to describe the present field of activities of analytical chemistry using environmental analysis as an example. Some conclusions concerning education in analytical chemistry at the universities are presented.

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Ausbildung in der Lösung von Problemen: Umwelt-Analytik

Zusammenfassung Am Beispiel Umwelt-Analytik wird versucht, das heutige Tätigkeitsfeld der Analytischen Chemie zu beschreiben und daraus einige Folgerungen für die Ausbildung in Analytischer Chemie an den Hochschulen abzuleiten.

     

Environmental and ecological studies using proton activation analysis

Multielement analyses of environmental samples have been carried out using proton activation analysis. It has been shown that this technique is suitable for both the analysis of aerosol particulates collected on polystyrene filters and for the analysis of the roots of Eucalyptus trees. Aerosol particulates from around the eastern coast of Australia were found to contain S, Ca, Ti, Cr, Fe, Ni, Cu, Zn, Ga, Se, Sr, Y, Zr, Ru, Pt and Hg ranging in concentration from <0.003 to over 3.0 μg per cubic metre of air. A comparison between the ashed roots of healthy and diseased Eucalyptus trees from the Brisbane Ranges in Victoria showed that the concentrations of Fe and Ti in the diseased tree were only 30% and 59% respectively of that in the healthy tree.     

Multielement analysis of Chinese Environmental Reference Materials by instrumental neutron activation analysis

Instrumental neutron activation analysis (INAA) has been applied for the simultaneous determination of up to 33 elements including major, minor and trace elements in the environmental reference materials soil and coal fly ash from China. The procedure involves both short and long irradiations followed by the measurement of the gamma spectra with a Ge(Li) detector. The analytical results are presented and discussed.     

Environmental analysis using gas chromatography — atomic absorption spectrometry

The combination of gas chromatography and atomic absorption spectrophotometry offers high sensitivity and specificity in the analysis of volatile organometallic species, and has been applied to alkyl derivatives of As, Pb, Se and Sn in environmental samples of air, water, sediment and biological tissues. Techniques of sample introduction and detector design are discussed with regard to the sensitivity attainable.     

Environmental analysis based on luminescence in organized supramolecular systems

The use of organized supramolecular systems—including micellar media and cyclodextrin inclusion complexes—combined with luminescence techniques in the study and determination of compounds and elements of environmental interest from 1990 to 2005 is reviewed. Analyses of environmental samples performed using fluorescence, photochemically induced fluorescence and phosphorescence spectroscopy as well as liquid chromatography, capillary electrophoresis and flow injection with luminescence detection in the presence of these organized media are described in detail.     

Environmental semivolatiles and nonvolatiles analysis by hyphenated spectral techniques

Environmental sample extracts contain a variety of volatile and nonvolatile organic compounds exhibiting a range of polarities and concentrations. Although gas chromatography/mass spectrometry (GC/MS) is the method of choice thus far for such analyses, this technique used alone cannot adequately characterize the volatiles in such samples and is not amenable to environmental nonvolatiles. A more complete characterization of environmental and hazardous waste samples is required to assess the dangers posed to the nation's groundwater by hazardous waste dumps. Online spectral confirmation by directly linked GC/Fourier transform infrared (FTIR)/MS is shown to provide useful structural information on environmental volatiles in hazardous wastes, even when the analyte's spectrum is not in either spectral database. This information can lead to biological-hazard estimation. The diffuse reflectance Fourier transform infrared (DRIFT) technique, used in conjunction with thermospray MS or fast atom bombardment (FAB) MS, provides confirmed identifications or confirmed compound class assignments of organic nonvolatiles in solid wastes. This is believed to be the first report of spectral confirmation (identification or functionality) of organic volatiles and nonvolatiles in environmental samples.     

Environmental analysis of higher brominated diphenyl ethers and decabromodiphenyl ethane

Methods for environmental analysis of higher brominated diphenyl ethers (PBDEs), in particular decabromodiphenyl ether (BDE209), and the recently discovered environmental contaminant decabromodiphenyl ethane (deBDethane) are reviewed. The extensive literature on analysis of BDE209 has identified several critical issues, including contamination of the sample, degradation of the analyte during sample preparation and GC analysis, and the selection of appropriate detection methods and surrogate standards. The limited experience with the analysis of deBDethane suggests that there are many commonalities with BDE209. The experience garnered from the analysis of BDE209 over the last 15 years will greatly facilitate progress in the analysis of deBDethane.     

Environmental trace-element analysis using a benchtop total reflection X-ray fluorescence spectrometer.

Total reflection X-ray fluorescence (TXRF) analysis is an established technique for trace-element analysis in various types of samples. Though expensive large-scale systems restricted the applications in the past, in this study the capability of a benchtop system for trace elemental analysis is reported. The suitability of this system for the mobile on-site analysis of heavy metal contaminated soils and sediments is reported as well as the possibilities and restrictions of TXRF for additional applications, including trace-element analysis of water, glass and biological samples.     

Environmental analysis of organic compounds in water using solid phase micro extraction

Solid Phase Micro Extraction (SPME) involves exposing a fused silica fiber coated with stationary phase to a contaminated water sample. The organic analytes become partitioned between the stationary phase and the water and when equilibrium is reached the fiber is removed from the solution and the analytes are thermally desorbed in the injector of a gas chromatograph. The fiber is contained in a syringe to facilitate handling. Factors which affect linear range, limit of detection, and total analysis time are discussed with regard to the development of a method for analysis of volatile compounds in environmental water samples. The sensitivity of the method was determined by the thickness of the film of stationary phase; the equilibration time, however, increased with the film thickness, although it can be minimized by use of a cross-shaped stirrer bar. Increasing the thickness of stationary phase in the analytical column enables the cryofocusing temperature to be increased from ?40 to ?15°C. With an ion trap mass spectrometer, detection limits required by the US Environmental Protection Agency are met for all compounds except chloromethane and chloroethane. The method has been applied to environmental water samples.     

Environmental and food analysis by desorption atmospheric pressure photoionization‐mass spectrometry

Desorption atmospheric pressure photoionization‐mass spectrometry (DAPPI‐MS) is a versatile surface analysis technique for a wide range of analytes, especially for neutral and non‐polar analytes. Here, a set of analytes typically found in environmental or food samples was analyzed by DAPPI‐MS. The set included five polyaromatic hydrocarbons (PAHs), one N‐PAH, one brominated flame retardant, and nine pesticides, which were studied with three different spray solvents: acetone and toluene in positive ion mode, and anisole in negative ion mode. The analytes showed [M + H]⁺, M^+?, and [M–H]^? ions as well as fragmentation and substitution products. Detection limits for the studied compounds ranged from 30 pg to 1 ng (from 0.14 to 5.6 pmol). To demonstrate the feasibility of the use of DAPPI‐MS two authentic samples – a circuit board and orange peel – and a spiked soil sample were analyzed. Tetrabromobisphenol A, imazalil, and PAHs were observed from the three above‐mentioned samples, respectively. The method is best suited for rapid screening analysis of environmental or food samples. Copyright © 2010 John Wiley & Sons, Ltd.     

Mass spectrometric confirmation criterion for product-ion spectra generated in flow-injection analysis. Environmental application

The suitability of a confirmation criterion recently recommended in the Netherlands for gas chromatography with mass spectrometric detection (GC–MS), was evaluated for flow-injection analysis (FIA) with atmospheric pressure chemical ionisation MS–MS detection. The main feature of the criterion is that the relative ion abundances of the four diagnostic ions are taken into account. That is, for lower-intensity peaks, relative standard deviations may be higher; this is an advantage with chemical ionisation MS procedures. A series of triazines and their degradation products were used as test compounds. Tap and surface water samples spiked at 0.33 μg/l were analysed by means of a selected reaction monitoring MS–MS procedure. For all analytes but hydroxysimazine (3 transitions), 4–9 transitions could be selected which invariably met the demands of the criterion. Some of the transitions used originate from the ³⁷Cl isotopic mass of the parent compounds which provides additional structural information. Data for twenty surface water samples analysed by means of FIA–MS–MS as well as GC–MS and liquid chromatography with diode array UV and MS–MS detection gave essentially the same results over the 0.1–1.0 μg/l range. In two samples desethylatrazine was reported by FIA–MS–MS whereas this compound was not detected by GC–MS. For a first test, this is a promising result.     

环境工程环境监测实验教学改革研究

以上海理工大学环境与建筑学院环境监测实验基地为基础,建立新的实验教学体系,进行实验环节的改革。按照监测实验的理论依据划分为容量法、重量法、电化学分析法、光谱法及色谱法5大类,以提高学生实际运用知识的能力,增强监测实验技能。     

Environmental matrices

AbstractsParticular products and fields of application

Environmental matrices     

环境超声化学

环境超声化学利用超声空化效应分解液相污染物,属于高级氧化过程。介绍了环境超声化学的基本原理,包括超声空化理论、超声降解环境污染物机理及生成自由基反应。综述了近年来环境超声化学在污染物净化中的应用,对存在问题和发展趋势提出了见解。