ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    ISSN: 1432-1130
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Six interlaboratory studies were organised by the Standard, Measurement and Testing Programme of the European Commission on the determination of arsenic species (arsenobetaine, arsenocholine, monomethylarsonic acid, dimethylarsinic acid, As(III) and As(V)) in marine matrices and soil. A step-by-step approach was used and a meeting was held at the end of each study to help the participants to discover errors and to improve their analytical methods. The successive steps investigated the calibration procedures on various solutions, the separation and derivatisation techniques on solutions and extracts and the extraction on mussel and fish tissues. All materials used for the study were monitored for their stability. Verified calibration solutions and compounds were distributed to the participants in each exercise in order to trace calibration problems. The agreement between the results improved regularly and at the end of the six campaigns allowed the certification of a reference material of tuna-fish tissue (BCR-CRM 627) for its total arsenic, arsenobetaine and dimethylarsinic acid contents.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1432-1130
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Interlaboratory studies have been organised by the Standards, Measurement and Testing Programme in order to certify the content of some chemical forms of arsenic in fish and mussel tissue, soil and sediment. Among the six compounds of interest (arsenite, arsenate, dimethylarsinic and monomethylarsonic acids, arsenobetaine and arsenocholine) only four are commercially available. Arsenobetaine and arsenocholine of well defined purity had therefore to be prepared by the pilot laboratories in charge of the management of the project. The present work deals with the synthesis and characterisation of these two compounds and the certification of the content of arsenobetaine in a standard solution (BCR-CRM 626).
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1432-1130
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Tuna fishes were collected in the Straits of Messina (Italy), were dissected and dorsal muscles minced, freeze-dried, ground and sieved. The obtained powder was stabilised by γ-irradiation and filled into brown glass bottles. The homogeneity and stability at +20 °C and +40 °C were verified with regards to the total arsenic, dimethylarsinic acid and arsenobetaine contents. Ten laboratories participated in the certification study. All participants had demonstrated beforehand their ability to produce accurate results for the As speciation in fish tissue. The certified values are: total arsenic (4.8 ± 0.3) mg/kg, arsenobetaine (52 ± 3) μmol/kg, dimethylarsinic acid (2.0 ± 0.3) μmol/kg. The material is available from the BCR since early 1998.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Fresenius' Zeitschrift für analytische Chemie 331 (1988), S. 58-60 
    ISSN: 1618-2650
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The energy dispersive X-ray fluorescence spectrometer (EDXRF) developped together with the Siemens Company (FRG) allows to perform rapid multi-elemental analysis of biological fluids without pretreatment of the samples. The performance of this technique and its features are reported in two different fields: blood analysis and pulmonary investigations. Blood and plasma analysis were performed for more than 2500 patients and a statistical treatment of the data lead to the normal concentrations of trace elements Se, Rb, Cu, Zn, Fe, Ca, Br, K. Toxic elements such as Hg or Pb and also drugs like Au and Pt compounds can be detected even after a long period after treatment. To illustrate the performance of the spectrometer we report the influence of Cis-Pt treatment on the trace element concentrations in plasma of patients with anemia. The EDXRF spectrometry was also used to investigate the inorganic composition of the broncho-alveolar lavage fluids. After determination of the normal concentration range, it was possible to characterize some typical pulmonary diseases due to occupational exposure. Some examples of detected pneumoconiosis and for some patients the presence in the alveoli of elements due to special medication (Amiodarone, Aurothiopropanol-sulfonate) are mentioned. Other fields are being investigated such as: follow-up of Mn dependent enzymes in neuronal and glial cells in culture; origin of lead in dental tissues or composition of lyophilized food powders. They will be briefly discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Fresenius' Zeitschrift für analytische Chemie 354 (1996), S. 550-556 
    ISSN: 1618-2650
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract An analytical procedure for total arsenic and arsenic species quantification in marine organisms has been developed. Fresh materials are freeze-dried and reduced to powders before analysis. Arsenic is determined either by energy dispersive X-ray fluorescence (EDXRF) directly or by inductively coupled plasma optical emission spectrometry (ICP/OES) after microwave digestion. Arsenic speciation is performed on the extracted sample using liquid chromatography coupled to ICP/OES for arsenobetaine and arsenocholine determination and to the hydride generation-quartz furnace atomic absorption spectrometric technique for arsenite, arsenate, monomethylarsonic and dimethylarsinic acids quantification. Special precautions are taken to avoid losses or contaminations as well as to prevent analytical errors during the quantification stage. Other methods are applied and the corresponding results compared for each step of the procedure. The method is finally validated by means of intercomparison studies within the Measurements and Testing Programme of the European Community (formely BCR).
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Arsenic compounds ; Polymeric styrene divinylbenzene phase ; Ion-pairing
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The resolving power of an ion-pair reversed-phase liquid chromatography method, on a polymeric stationary phase (PRP-1) with an alkaline aqueous mobile phase (pH=9) containing tetrabutylammonium cation as ion-pairing agent, is compared with a traditional ion-pairing system using an octadecyl-modified silica column and a neutral aqueous mobile phase (pH=7.3). This chromatographic system (PRP-1 column) provides a rapid means for the determination of two of the most important arsenic species, arsenobetaine and arsenite. Addition of methanol (5%) to the aqueous mobile phase allows the differentation of arsenobetaine from the system peak when using UV detection.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 424 (1976), S. 59-67 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reaktionen von Acetylbromid mit Lewis-Säuren. I. Raman-Untersuchung der Systeme MCl4—CH3COBr (M = Ti, Sn)Die Systeme MCl4—CH3COBr (M = Ti, Sn) wurden durch ihre Raman-, infrarot- und kernmagnetische Resonanzspektren untersucht. Die zwei letzteren Methoden zeigen, daß weder der acetylion, CH3CO+, noch der TiClxBry komplex vorhanden sind. Die Zuordnung der Ramanspektren erfolgt auf Grund der Annahme, daß Halogenaustausch zwischen MCl4 und CH3COBr zu MBr4 und CH3COCl, und zu gemischten Derivaten der Typus MClxBr4-x führt. Veränderungen der Redoxzustände werden hierbei nicht beobachtet.
    Notes: In order to study the systems MCl4—CH3COBr (M = Ti, Sn), the Raman, infrared and PMR spectra of a number of solutions MX4 + R CH3COY in CCl4 ({X, Y} = {Cl, Cl}, {Br, Br}, {Cl, Br}) have been recorded. The PMR and i.r. studies show the absence of both CH3CO+ ion and the oxo-donor species. The Raman spectra are consistent with an halogen exchange between MCl4 and CH3COBr, leading to MBr4 and CH3COCl, and all the mixed halides MClxBr4-x. No redox reaction was observed.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1618-2650
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Capillary zone electrophoresis has been used for the separation of arsenite, arsenate, monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) and phenylarsonic acid. The separation was achieved using a fused silica capillary filled with a phosphate buffer. The on-column U.V. detector was operated at 190 nm. The influence of voltage and injected volume, reproducibility of calibration and recovery from a drinking water sample were studied. Using the calibration plot method and phenylarsonic acid as internal standard the mean recoveries for arsenate, MMA and DMA were 104%, 97% and 97% respectively.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1618-2650
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Capillary zone electrophoresis (CZE) has been used for the separation of bromide, bromate, iodide, iodate, nitrite, nitrate and selenite anions. The separation was achieved using a fused silica capillary (72 cm long x 50 μm i.d.) filled with an acidic phosphate buffer (pH=3, 25 mmol/l), and with on-column UV detection at 200 nm. The influence of different experimental parameters such as pH, ionic strength and voltage, was studied. The nitrate concentration of a Rhine water sample was then determined under selected conditions and the results were compared to those obtained by high performance ion chromatography (HPIC).
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 372 (1970), S. 113-118 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The electronic absorption spectra of the ions PS43-, AsS43- and SbS43- have been measured in aqueous solution. The transitions are assigned and discussed, using a simple MO diagram.
    Notes: Es wurden die Elektronenspektren von PS43-, AsS43- und SbS43- in wäßriger Lösung gemessen. Alle Ionen weisen unterhalb von 54 kK lediglich eine starke Bande auf. Die Banden werden an Hand eines stark vereinfachten MO-Schemas zugeordnet. Es läßt sich zeigen, daß bei den oben erwähnten Ionen praktisch keine π-Bindungen vorliegen.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...