Volume 76, Issue 6

This paper presents quantities, terminology, and symbols of terms related to photothermal phenomena and used in photothermal and related spectroscopies. The terms used in the literature to describe photothermal phenomena and methods are reviewed, and a glossary of terms is given. The origins of photothermal phenomena, as well as the relations among various photothermal effects, are summarized. The listed terms cover the terminology in transient grating, transient lens, photoacoustic spectroscopy, photothermal radiometry, calorimetry, interferometry, deflection, reflection, and other related spectroscopies, which use or are related to photothermal effects.

Liquid flow analytical techniques are classified, and definitions are provided of flow-injection analysis, segmented flow analysis, flow titration, continuous monitoring, liquid chromatography, and capillary electrophoresis. Electrochemical detection and flow through detection cells are characterized with respect to the surface and bulk detection. The detector performance is discussed in terms of its principal analytical parameters, such as detection limit and dynamic concentration range, as well as its dynamic characteristics, such as the response time, sampling frequency, transport lag, and long-term stability. Moreover, different detection modes are critically evaluated, including both potentiostatic and galvano-static techniques. Factors influencing sensitivity and detection limit, which include electronic and hydrodynamic approach, are also discussed. Different detector designs are critically reviewed, and the special features of electrochemical detectors for flow analytical techniques are emphasized.

Piezoelectric chemical and electrochemical sensors are classified. Basic terms and definitions related to piezoelectric materials and sensing devices, electric transducers, and analytical measurements with piezoelectric chemical sensors are provided. In addition, the more essential response equations are presented.

The quantitative analysis of thin films containing light elements is very important in improving the coating processes and technological properties of the products. In order to review the state of the art of modern analytical techniques for such applications, the model systems SiO X N Y and AlO X N Y were selected. Over 1000 abstracts were screened, and the relevant literature was evaluated to give a comprehensive overview of instruments, analytical procedures and results, film types, deposition methods, and investigation goals. From more than 150 citations, the limitations, drawbacks, and pitfalls of the different methods were extracted and reviewed critically, while in addition, improvements were proposed where possible. These suggestions are combined with the newest results of investigation by the authors of this paper. Recommendations concerning the optimized combination of analytical methods for different analytical problems have been worked out on the basis of all results. Analysis of various multicomponent systems containing light elements demonstrated the applicability of the different methods of analysis in combination to all film systems with related compositions.

Calibration in analytical chemistry refers to the relation between sample domain and measurement domain (signal domain) expressed by an analytical function x = f s (Q) representing a pattern of chemical species Q and their amounts or concentrations x in a given test sample on the one hand and a measured function y = f ( z ) that may be a spectrum, chromatogram, etc. Simultaneous multispecies analyses are carried out mainly by spectroscopic and chromatographic methods in a more or less selective way. For the determination of n species Q i ( i = 1,2 … n ), at least n signals must be measured which should be well separated in the ideal case. In analytical practice, the situation can be different.

Emissions caused by the use of coal and by traffic have caused serious photochemical smog and aerosol pollution with unique characteristics in most Chinese cities. This report gives an overview of aerosol concentrations in China based on data obtained from both the literature and recent research by the authors. The results show that TSP (total suspended particulate) and PM-10 (particles with aerodynamic diameter 10 µm) concentrations frequently exceed the National Ambient Air Quality Standard and that ambient aerosol concentrations constitute a serious air pollution problem. PM-2.5 concentrations are also high and account for 60 % of the PM-10 mass. Organic carbon and sulfate are the most abundant components of PM-2.5, while crustal elements represent a minor portion.Nitrate concentrations are almost the same as sulfate in summertime, which implies that NO x control is very important in lowering fine particle concentrations and in improving air visibility. The chemical mass balance (CMB) method was applied in Beijing to identify the sources of PM-2.5. The main sources include fugitive dust, coal burning/industrial processes, traffic emissions, and secondary aerosol produced by atmospheric chemical conversion.

Aerosols play an important role in all problems connected with air pollution, ranging from very local effects and human health problems to regional problems such as acid deposition and eutrophication up to continental and global questions such as stratospheric ozone loss and climatic change. In this report, an explanation of these effects is given and an assessment is made for parts of China, based on the aerosol data given by Zhang et al . elsewhere in this volume. ( Pure Appl. Chem. 76(6), 1227-1239, 2004) Epidemiological research has made clear that aerosols are a cause of enhanced mortality due to cardiopulmonary diseases (heart and lung diseases). Based on the same mortality as found in Europe and on linear extrapolation (with large uncertainties; no sufficient data are available to make better estimates), an excess mortality of 5000 to 10 000 due to acute effects and 20 000 to 50 000 due to chronic effects per year could be expected for a city like Beijing with a population of 14.5 million. A major cause of these uncertainties is problems in the determination of semivolatile compounds and elemental or black carbon in aerosols. Aerosols have a strong impact on the radiative balance of the earth, in a direct way by reflecting solar light as well as in an indirect way by cloud formation leading to clouds with higher albedo, which reflect sunlight better. The total direct effect, backscatter of sunlight, including backscatter from nitrates and organic compounds, is estimated to be approximately 2 to 3 W m –2 for Western Europe, while the indirect effect is approximately 0 to –6 W m –2 . Soot absorbs incoming solar radiation and heats the atmosphere. This process contributes 0.1 to 0.2 W m –2 on a global scale. If PM-2.5 levels are compared with Europe, a direct effect of approximately –4 to –10 W m –2 would be plausible for China, black carbon could contribute probably about 0.5 to 2 W m –2 , and the indirect effect could be about 0 to –6 W m –2 . These effects could cause a net cooling over China (and over many developing countries in the same position) of about –4 to –15 W m –2 . This estimate is obviously based on many assumptions and hence is quite uncertain. One must be aware that measures reducing local aerosol concentrations will have a large impact on the radiative balance and could, over a few decades, have potentially at least the same impact as the build-up of greenhouse gases since the beginning of the Industrial Revolution.

A project is underway within IUPAC to evaluate and harmonize the use of various biomarkers for immunosensitization to metals. This present review summarizes our knowledge of the mechanisms by which certain trace elements evoke allergenicity. Some physiological electrolytes (e.g., Na + , K + ) and macronutrients (e.g., Ca 2+ , Fe 3+ ) are immunologically inactive. However, some trace elements essential for cell function (e.g., Co 2+ , Cu 2+ , Cr 3+ ), as well as nonessential elements generally considered toxic (e.g., Hg species) or in use as therapeutic agents (e.g., some species of Pt and Au), can give rise to adverse immune reactions. Specific immunological responses to Ni, Co, Cr, Hg, Be, Cu, Pt, Pd, Ir, In, and Au are discussed. In general, these elements can activate T or B cells by specific receptor interactions, resulting in clonal expansion of a metal-specific lymphocyte and an immune response (typically dermatitis) upon re-exposure. Compelling evidence points to the primary role of the T cell in responding to the metal. T-cell activation occurs when a protein of the major histocompatibility complex (MHC) binds to a T-cell receptor in the presence of an MHC binding peptide. Many antigenic substances result in presentation of MHC bound antigenic peptides to the T-cell receptor; metal ions appear to act as haptens that directly or indirectly cause structural changes in MHC molecule-peptide complexes that result in recognition of these complexes by specific T-cell subsets. Nickel and gold are particularly instructive in understanding mechanisms, and are used to discuss models in which the metal may bind to the antigenic peptide (i) before or (ii) after its association with the MHC/T-cell receptor complex, (iii) may bind to the MHC/receptor complex prior to recruitment of the antigenic peptide, or (iv) may bind to the formed peptide/MHC/receptor complex through ligands contributed by one or more of the components.

The lymphocyte transformation test (LTT) has been proven useful especially in the diagnosis of drug-induced allergic disorders. It is an in vitro test which is based on the fact that lymphocytes, which have been sensitized by a certain antigen, transform into blasts and proliferate when they are again exposed to this antigen. This proliferation is determined by measurement of the incorporation of [ 3 H ]-thymidine or bromodeoxyuridine into replicating DNA. The test has the advantage over skin tests of avoiding re-exposure of individuals, and it was, therefore, hoped that it may also help to diagnose metal allergies and especially sensitization toward beryllium. However, the LTT measures only the sensitization of lymphocytes, but not the effector reaction, i.e., there may be positive results in exposed individuals even in the absence of clinical symptoms. There are several reports evaluating the LTT toward gold salts (Au), amalgam (Hg), nickel (Ni), beryllium (Be), and several other metals. With metals other than Be, the LTT appears to be of little use. In contrast, the LTT with Be may, indeed, define patients at risk of developing chronic beryllium disease (CBD), which affects mainly the respiratory tract and may even cause death. Beryllium sensitization progresses to CBD at a rate of 7-11 % per year. Since the Be-LTT can detect sensitization in workers who have not yet developed a disease it is an important diagnostic tool to detect individuals at risk. In conclusion, the LTT can detect a cell-mediated immunological response of an individual to metals. However, for most metals its usefulness is questionable, with the exception of Be; a positive Be-LTT can identify not only patients with CBD, but also persons at risk of developing CBD in later years.

Since publication of "Revised Section F: Natural products and related compounds" in Pure Appl.Chem . 71 , 587-643 (1999), a number of errors have been detected. Further consideration of some sections now requires some extensions or further explanation. These changes are listed below.

As was drawn to my attention by Prof.Y. Naruta (Institute for Fundamental Research of Organic Chemistry, Kyushu University, Japan; <naruta@ms.ifoc.kyushu-u.ac.jp>), the chemical structure in original Fig. 5 erroneously omitted 3-methyl groups from the distal pyridines and showed an ether rather than the correct amide linker between the porphin and the distal superstructure. In addition, the caption did not make it sufficiently clear that the O 2 adduct is a monocation,whose counterion, BF 4 − , was omitted for clarity.The corrected version of Fig. 5 with the caption is below.