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1.
《Analytical letters》2012,45(15):2909-2924
ABSTRACT

A brief overview of analytical chemistry research in Australia is presented and reference is made to the work of several research groups. Topics covered include the development of a longitudinally modulated cryogenic system for comprehensive gas chromatography, mixed-mode capillary electrochromatography for manipulation of separation selectivity of inorganic ions, new developments in chemical metrology, discontinuous flow analysis and its applications, the design and applications of an orthogonal acceleration time-of-flight mass spectrometer, and the use of chemiluminescence in a range of analytical techniques.  相似文献   

2.
《Analytical letters》2012,45(8):vii-xxxv
Abstract

One of the fascinating features of analytical chemistry is the continuous challenge it provides the practitioners of this profession. As we are confronted with our current analytical problems and anticipate even more thought provoking and complex problems in the future it is reassuring to pause and examine the progress that has been made and is being made in the development of sensitive, specific and rapid methods of chemical analysis. Relevant to solving complex analytical problems and in handling samples of unusual complexity I would like to quote a sentence from one of Professor Laitinen's recent editorials in ANALYTICAL CHEMISTRY: “It boils down to the fact that complex mixtures will become increasingly important in the future, but no matter how sophisticated the instrumentation may become, the analytical chemist will continue to be the most important component in the solution of analytical problems”1. A review of the historical developments in analytical chemistry does indicate the importance of individuals and their unique resourcefulness, creativity and rational thinking in responding to practical problems and their own scientific curiosity.  相似文献   

3.
《Analytical letters》2012,45(10):ix-xiii
Abstract

In this day and age it is not an easy task to describe in a few pages the current status of any scientific discipline. This is particularly difficult if one deals with a n area such as analytical chemistry in France which is on the upswing. The present wirteup is focused on developments in French universities since the war: we shall not deal with analytical chemistry in industry, even though chemical companies and the French Atomic Energy Commission have had a paramount influence on recent developments. Indeed, French analytical chemists are being educated mainly to serve the needs of industrial laboratories.  相似文献   

4.
《Analytical letters》2012,45(1):ix-xvii
Abstract

In the USSR analytical chemistry is one of the most important of the chemical disciplines. Since its beginning as an independent part of the chemical research, analytical chemistry has developed as an integral part of the political economy, and serves the practical needs of industry, as well as being a theoretically well-founded science. Besides economically important problems like the analysis of the composition of sediments of raw materials, quality control in metallurgy and in the production of rare elements, analytical control in the chemical, pharmaceutical, nuclear-energy and semiconductor production are of importance, and furthermore, analysts develop their own theory, and success in many phases of development are related to a knowledge of other sciences, especially to physics, mathematics, general chemistry, metallurgy, biology, etc.  相似文献   

5.
Stimulated by the rapid growth of analytical chemistry in research and development, a discussion on the past, present and future role of analytical chemistry as part of the chemistry curricula at European universities is presented in this article. The present status of analytical chemistry curricula is described, based on a recent investigation of the Working Party on Analytical Chemistry (WPAC) of the Federation of European Chemical Societies (FECS) at 229 European universities. The evaluation of the questionnaires has been done for all institutions together, as well as for the 119 institutions with a separate chair or department of analytical chemistry and the 110 institutions without such a separate chair. The distribution of teaching hours between the classical and modern fields is generally significantly better and more flexible to new developments (like chemometrics, environmental and material sciences) at institutions with an own chair of analytical chemistry. This survey is also a key to earlier reviews on education in analytical chemistry stimulated and published by WPAC-members.  相似文献   

6.
Abstract

Thin-layer chromatographic separation of metal ions has become immensely popular in analytical chemistry in view of its speed, selectivity and applicability at tracer level. Quinoline-2-aldehyde thiosemicarbazone1,2 was found to form yellow coloured chelates with metal ions such as copper, nickel, zinc, mercury, iron and lead at pH 7.5 and extract into chloroform. This, however reduces the sensitivity of the reagent as a chromogenic agent but the chromatographic run of the chelates on a thin layer of silica gel coated on glass plate increases the specificity and selectivity of the reagent. In this article we propose a method for separation of copper and mercury chelates from binary mixtures containing chelates of zinc, lead, iron and nickel. The method is applicable for analysis of synthetic mixtures and standard samples.  相似文献   

7.
从研究分析化学的历史发展入手,以大量历史事实为根据,指出分析化学曾经历过两次重大变革。第一次变革(19世纪末至20世纪初)使分析化学从分析化学家的技艺发展为科学;第二次变革(20世纪70年代迄今)则使分析化学进入了分析化学家重新当家作主的、欣欣向荣的“第二个春天”。  相似文献   

8.
《Analytical letters》2012,45(9):581-587
Abstract

Until now there has been no attempt to write the complete history of analytical chemistry in Romania. Nevertheless, we consider it important that our young chemists learn about the history of analytical chemistry in our country, because you can never step forward if you disregard the past. Furthermore, scientists in other countries might find the history and current status of analytical chemistry in Romania of interest.  相似文献   

9.
The NMR technique is among the most powerful analytical methods for molecular structural elucidation, process monitoring, and mechanistic investigations; however, the direct analysis of complex real-world samples is often hampered by crowded NMR spectra that are difficult to interpret. The combination of fluorine chemistry and supramolecular interactions leads to a unique detection method named recognition-enabled chromatographic (REC) 19F NMR, where interactions between analytes and 19F-labeled probes are transduced into chromatogram-like 19F NMR signals of discrete chemical shifts. In this account, we summarize our endeavor to develop novel 19F-labeled probes tailored for separation-free multicomponent analysis. The strategies to achieve chiral discrimination, sensitivity enhancement, and automated analyte identification will be covered. The account will also provide a detailed discussion of the underlying principles for the design of molecular probes for REC 19F NMR where appropriate.  相似文献   

10.
    
Summary To fulfil the requirements set by analytical chemistry to a symbolic iconic language, the SSSAC-system (Symbolic Synoptic System for Analytical Chemistry) has to be adapted drastically. The most urgent adaptions are: that the system should be selfcorrective by redundancy; that it should convey more information than in its momentary form; that writing or drawing the language should become much easier by simplifying the symbols; that translation into a computer language should be possible and that retrieval must be possible. A system based upon (formalized) plain language seems more adaptable to analytical chemistry.Paper by H. Malissa and V. Simeonov, Fresenius Z. Anal. Chem. 289, 257–263 (1978)  相似文献   

11.
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.
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.
  相似文献   

12.
The method used at LGC for analysis of “total” 19-norandrosterone (19-norandrosterone glucuronide plus “free” 19-norandrosterone) in urine for the Comité Consultatif pour la Quantité de Matière Pilot Study (CCQM-P68) is described. The analytical method used was a modified version of the method developed at the National Measurement Institute of Australia, which used a hydrolysis and derivatisation procedure first described by the German Sports University. This method is routinely used by World Anti-Doping Agency-accredited laboratories for sports drug testing. The main modifications made to the method were the use of 19-norandrosterone glucuronide as a calibration standard and 19-norandrosterone glucuronide-d4 as an isotopically labelled internal standard, and the use of a bench-top quadrupole gas chromatograph–mass spectrometer. The results produced by LGC (2.14 ± 0.15 ng g−1 expanded uncertainty, coverage factor k = 2) were in excellent agreement with those from other participating national metrology institutes and thus further validates the exact-matching isotope-dilution mass spectrometric procedures used at LGC for a wide range of reference measurement applications, including measurement of ng g−1 levels of steroids in a biological matrix.  相似文献   

13.
《Analytical letters》2012,45(7):1203-1229
ABSTRACT

The paper presents the main achievements of analytical chemistry in Poland on the basis of papers published mainly in the last decade. The selection is somewhat arbitrary but should show the most important directions of research. The citations generally refer to papers published in regular journals. The following topics were discussed: general aspects, chemical methods and reagents, spectrophotometry, speciation studies, atomic spectrometry, electrochemical methods, chemo- and biosensors, chromatography and related techniques.

Short reviews on the history and present status of analytical chemistry have been published elsewhere1, 2 and this review is intended to present the more detailed overview of the recent fields of interest, based on some selected publications from the nineties. Such selection is obviously to some extent arbitrary and this is mainly based on information sent by colleagues from various centres. It seemed, however, necessary to indicate where appropriate, the roots and earlier achievements.  相似文献   

14.
Undergraduate organic chemistry special laboratory projects based upon the synthesis of phencyclone, 1 (a potent Diels-Alder diene), and the preparation of a series of highly hindered Diels-Alder adducts of the phencyclone, were described earlier. Details of the synthesis of an analogue of 1 are presented here as an extension of these projects. The analogue, 3,6-dibromophencyclone, 2, and adducts from a wide range of dienophiles, can be prepared by undergraduate organic chemistry students. These adducts (from 1 or 2) are eminently suitable for student characterization by NMR to examine aspects of hindered rotation, magnetic anisotropy, and dynamic NMR spectroscopy, using modern one- and two-dimensional multinuclear methods with a medium-field instrument (7 T), to observe 1H, 13C, and 19F. Use of 2 effectively doubles the range of potential target compounds for students. The Diels-Alder adducts (and their precursors) have been studied by molecular modeling methods. This present paper describes the reaction of 2 with 4, the dienophile N-(4-dimethylamino-3,5-dinitrophenyl)maleimide (Tuppys maleimide), to form the adduct 5. Compound 5 has been well-characterized by 1D and 2D 1H and 13C NMR, and is illustrative of the wide range of adducts that can be made from 2 by students. The structure of 5, as determined by geometry optimization at the semiempirical (AM-1) level, is included here.  相似文献   

15.
Abstract

Nitrogen-containing heterocyclic compounds play an important role in several biological processes. Furthermore, their biological activity seems often to depend upon interaction with a metal ion. Interest in the study of hydrazones and their metal complexes has been growing because of their physiological activity, coordination capability and application in analytical chemistry.1,2 Many hydrazones and their metallic derivatives show very interesting biological activity, e.g., as antitumour or anticonvulsant agents, and behave as cytotoxic compounds toward tumour cells.3 During the past few years, in addition to platinum compounds, coordination compounds of palladium(II) and (IV) seem to be promising in cancer chemotherapy.4 Due to the biological activity of heterocyclic hydrazones and in continuing our systematic investigations of the platinum group metals with hydrazones and generally with heterocyclic nitrogen donor ligands,5–10 we report here the crystal structure of dibromo(phenyl-2-pyridyldimethylhydrazone) palladium(II).  相似文献   

16.
Abstract

A new hexaniobate complex with chromium(III) was prepared and characterised by analytical and spectroscopic techniques. The compound is a violet, non-crystalline solid, formulated as [Cr2(μ-OH)(H3Nb6O19)(en)3(H2O)]. It was synthesised in aqueous solution by reaction of [Cr(en)3]3+, en = ethylenediammine, with the hexaniobate anion [Nb6O19]8-, at pH 8. Thermal decomposition yielded a mixture of CrNbO4 and Nb2O5. The synthesis of this compound shows that the hexaniobate anion may form complexes at lower pH values than previously reported.  相似文献   

17.
Abstract

The relationship between ring strain and the reactivity of alicyclic compounds has been of fundamental importance in the development of modern organic chemistry. Because of their biological interest, the reactivity and stereochemistry of cyclic phosphorus compounds have been extensively studied.1,2 In recent years the reactivity of cyclic sulfur compounds has also begun to attract considerable interest. In 1966 it was pointed out that the common feature of sulfur-containing heterocycles is that nucleophilic attack at sulfur, be it di-, tri-, or tetra-coordinated, is always faster than the corresponding open-chain analogues.3 The present review attempts to discuss some fo the factors which affect the reactivity of cyclic sulfur compounds towards nucleophilic attack and to draw attention to some of the recently observed exceptions to this generalization.  相似文献   

18.
Abstract

1,1-Bis(diphenylphosphino)ethene, 1a, was originally prepared by Colquhoun and McFarlane1 by the reaction of lithium diphenylphosphide and vinylidene chloride. Subsequently, Schmidbaur et al.,2 reported further novel chemistry of 1a and its derivatives such as 1b and 1c.  相似文献   

19.
《Ambix》2013,60(3):279-298
Abstract

This article centres on a particularly intense debate within British analytical chemistry in the late nineteenth century, between local public analysts and the government chemists of the Inland Revenue Service. The two groups differed in both practical methodologies and in the interpretation of analytical findings. The most striking debates in this period were related to milk analysis, highlighted especially in Victorian courtrooms. It was in protracted court cases, such as the well known Manchester Milk Case in 1883, that analytical chemistry was performed between local public analysts and the government chemists, who were often both used as expert witnesses. Victorian courtrooms were thus important sites in the context of the uneven professionalisation of chemistry. I use this tension to highlight what Christopher Hamlin has called the defining feature of Victorian public health, namely conflicts of professional jurisdiction, which adds nuance to histories of the struggle of professionalisation and public credibility in analytical chemistry.  相似文献   

20.
We measured serum 25 hydroxyvitamin D [25(OH)D] levels of ambulatory adults in tropical Australia to determine whether it is appropriate to continue promoting sun‐safety in this population. In August 2006 (winter), self‐administered questionnaires were completed by 145 Meals‐on‐Wheels volunteers (49.3% male; mean age 57.8 ± 14.7 years; 76.6% response) from Townsville, Queensland (Latitude 19oS). Serum 25(OH)D was analyzed using two common assays. Mean levels were 68.3 (SD ± 18.7; range 26–142) by DiaSorin Radioimmunoassay and 83.0 (SD ± 30.8; range 30–184) by DiaSorin Liaison® one. No participants were 25(OH)D deficient (<25 nmol L−1). Nine participants (6.2%) had 25(OH)D levels between 25 and 50 nmol L−1 (insufficient), by both methods (seven with a BMI ≥ 25). Twenty‐eight participants (19.3%) had one result in the insufficient range and the other in the adequate range. Thus, almost all of these free‐living adults in tropical Australia had adequate vitamin D levels at the end of winter. There was poor agreement between the two 25(OH)D assays. These results suggest it is appropriate to continue promoting sun‐safe messages to the ambulatory Caucasian adult population of North Queensland, which has an extremely high incidence of skin cancer. The lack of agreement between the two assays is a concern. Few doctors are aware of this measurement issue.  相似文献   

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