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  • 1
    Electronic Resource
    Electronic Resource
    An Alternative to Automatic Titration (1977)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 60 (1977), S. 3012-3014 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Automatic titrators are designed to do exactly what a lab-technician used to do. Much more sophisticated automation of volumetry is possible. Omegaphoresis [3] in buffer-free [2] sample solutions automatically creates a stationary multiple component titration curve or zoned pattern with normalized concentrations of each separated species. An automatic measurement of each zone length yields their quantity. Simultaneous automatic detection of all the zones in a 10-20 component solution in less than 2 minutes, with a precision of ±2%, a required amount of the order of less than one nanomol and a resolution of ±pK 〈 0.01 replaces acid-base, complexometric, and certain types of redox-titrimetry. An option of the method allows identification of the components as well.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19770600852
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  • 2
    Electronic Resource
    Electronic Resource
    On Metal-Atom Clusters IV. Photoionization thresholds and multiphoton ionization spectra of alkali-metal moleculesPapers I to III of this series, see [1-3].In memory of Professor Heinrich Labhart (1978)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 61 (1978), S. 453-487 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The investigation of electronic and structural parameters of metal molecules as a function of size may be decisive for understanding and control of heterogeneous catalysis with finely divided metals. Metal-atom clusters can be prepared by several methods, most of which yield a molecular mixture only. Expansion of an atomic vapour into vacuum through a supersonic nozzle creates a complex cluster-spectrum which has been investigated by photoionization using a mass-spectrometer as selective detector. Broad band single photoionization (PI.) yields the abundances and ionization thresholds for Nax(x≤16), Kx(x≤12) and NaxKy(x+y≤6). Rough indications about other deactivation channels of excited alkali-molecules are obtained from an analysis of the photoionization efficiency (PIE.) curves. Two-photon PIE. curves with narrow-band (laser) light sources give an accurate photoionization threshold value and detailed information on ionization processes. Two-photon ionization spectra via a real intermediate state reached by laser excitation are equivalent to normal absorption spectra, if the exciteation step is controlled by the true transition probabilities. By investigation of the power dependence of the ion current of Na2+ as a function of the wavelength of the tunable cw dye laser (excitation) and of the ionizing Ar+- or Kr+-laser, conditions under which true spectra are obtained have been clarified, in good agreement with a photon-kinetic model of the processes involved. Vibronic and rovibronic spectra of several transitions in Na2 and K2 have been measured. Similarly a spectrum of Na3 has been determined mass-selectively. The scope of the new method for an absorption spectroscopy in molecular beams is discussed.
    Additional Material: 27 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19780610141
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  • 3
    Electronic Resource
    Electronic Resource
    Verweilzeitmessung von Flüssigkeits- und Gasphase in großen Blasensäulen mit radioaktiven IndikatorenVortrag auf der internen Arbeitssitzung des GVC-Fachunterausschusses „Anwendung von Radioisotopen in der Verfahrenstechnik“ am 2./3. März 1978 in Frankfurt/M.-Höchst. (1978)
    Weinheim : Wiley-Blackwell
    Chemie Ingenieur Technik - CIT 50 (1978), S. 967-967 
    Details
    ISSN: 0009-286X
    Keywords: Blasensäule ; Radioindikator ; Verweilzeitmessung ; Verweilzeitverteilung ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cite.330501219
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  • 4
    Electronic Resource
    Electronic Resource
    Verweilzeitverhalten der flüssigen Phase in Blasensäulen größerer DurchmesserAuszugsweise vorgetragen von V. Schumacher auf dem 5. Int. Symp. on Chem. Reaction Engineering 1978 in Houston/Texas, USA. (1978)
    Weinheim : Wiley-Blackwell
    Chemie Ingenieur Technik - CIT 50 (1978), S. 811-811 
    Details
    ISSN: 0009-286X
    Keywords: Blasensäle ; Füllkörperreaktionstrum ; Gas-holdup ; Verweilzeitverteilung ; Momentenmethode ; Bodenstein-Zahl ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cite.330501022
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  • 5
    Electronic Resource
    Electronic Resource
    Studien zum Vorgang der Wasserstoffübertragung, 39. Langlebige Hydrierkatalysatoren durch kovalente Verknüpfung von Phosphin-Rhodium-Komplexen an Aerosil 200 (1976)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1976 (1976), S. 633-640 
    Details
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Studies on the Occurrence of Hydrogen Transfer, 39.  -  Long-Lived Hydrogenation Catalyst by Covalent Fixation of Phosphine-Rhodium-Complexes on the Surface of Aerosil 200The covalent binding of hitherto homogeneous phosphine-rhodium catalysts to “Amino-aerosil” is described. The dependence of the rate of catalysed hydrogenation upon the distance between the reaction centre and the silica support, and also upon temperature, solvent, and olefin structure, is discussed.
    Notes: Homogene Phosphin-Rhodium-Katalysatoren werden durch kovalente Bindung an ‘Aminoaerosil’ heterogenisiert. Die Abhängigkeit der Hydriergeschwindigkeit von der Entfernung der aktiven Zentren zur Oberfläche, von der Temperatur, vom Lösungsmittel und von der Struktur der eingesetzten Olefine wird untersucht.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.197619760407
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  • 6
    Electronic Resource
    Electronic Resource
    The kinetics and the mechanism of the thermal decomposition of bis-pentafluorosulfurtrioxide (SF5OOOSF5) (1979)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 11 (1979), S. 613-619 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermal decomposition of SF5O3SF5 has been investigated between 5 and 25°C. In the presence of sufficient high pressures of O2 the only products formed are SF5O2SF5 and O2: \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm SF}_5 {\rm O}_3 {\rm SF}_5 { } \to { SF}_{5} {O}_{2} {SF}_{5} { + (}{\raise0.5ex\hbox{$\scriptstyle {1}$} \kern-0.1em/\kern-0.15em\lower0.25ex\hbox{$\scriptstyle {2}$}}{) O}_{2} {, }\Delta n{ = }{\raise0.5ex\hbox{$\scriptstyle {1}$} \kern-0.1em/\kern-0.15em \lower0.25ex\hbox{$\scriptstyle 2$}} $$\end{document} The reaction is homogeneous. Its rate is strictly first order with respect to the trioxide pressure and independent of the total pressure of the reaction products and of oxygen above a certain limiting pressure: \documentclass{article}\pagestyle{empty}\begin{document}$$ - \frac{{{\rm d}[{\rm SF}_5 {\rm O}_3 {\rm SF}_5 ]}}{{{\rm dt}}}{ = + }\frac{{{\rm d}[{\rm SF}_5 {\rm O}_2 {\rm SF}_5 ]}}{{{\rm dt}}}{ = 2}\frac{{{dp}}}{{{\rm dt}}}{ = k[SF}_{5} {O}_{3} {SF}_{5} {]} $$\end{document} The experimental results can be explained with the following mechanism: In the presence of O2 〉 100 Torr the concentration of SF5 is insignificantly small. Therefore reactions (5) and (6) do not have to be considered any more, and steps (2) and (2′) will be of no importance. From reactions (1)-(4) it follows: \documentclass{article}\pagestyle{empty}\begin{document}$$ - \frac{{d[{\rm SF}_{\rm 5} {\rm O}_{\rm 3} {\rm SF}_{\rm 5} ]}}{{dt}} = + \frac{{d[{\rm SF}_{\rm 5} {\rm O}_{\rm 2} {\rm SF}_{\rm 5} ]}}{{dt}} = k_1 \frac{{[{\rm SF}_{\rm 5} {\rm O}_{\rm 3} {\rm SF}_{\rm 5} ]}}{{1 + k'_1 (1/2k_3 k_4 )^{1/2} }}k({\rm sec}^{{\rm - 1}}) = k_1 /\left[ {1 + k'_1 \left({\frac{1}{{2k_3 k_4 }}} \right)^{1/2} } \right] = 10^{16.06 \pm 0.37} {\rm exp( - 26,000} \pm {\rm 500}\,{\rm cal)/1}{\rm .987 }T $$\end{document}The numerical value of the factor [1 + (k′12/2k3k4)1/2] is small. It can be estimated that E3 ≃ 2 ± 1 kcal; therefore, E - E1 ≤ 1 kcal, and D (SF5O—O2SF5) = (26 - 1) ± 1.0 kcal.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550110608
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  • 7
    Electronic Resource
    Electronic Resource
    Kinetics of the thermal decomposition of bis-pentafluorine sulfur peroxide in the presence of carbon monoxide (1978)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 10 (1978), S. 111-116 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermal decomposition of F5SOOSF5, P, in the presence of CO has been investigated between 130.1° and 161.9°C at total pressures between 50 and 600 torr. The reaction is homogeneous, and the only final products formed are CO2 and S2F10. The rate of reaction is proportional to the pressure of P. The partial pressures of CO and O2 and the total pressure have no influence on the course of reaction: \documentclass{article}\pagestyle{empty}\begin{document}$$ - \frac{{d\left[P \right]}}{{dt}} = k\left[P \right] $$\end{document}The results are explained by the following mechanism:
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550100109
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  • 8
    Electronic Resource
    Electronic Resource
    Studies by the electron cyclotron resonance (ECR) technique. XII. Interactions of thermal-energy electrons with the molecules CHF3, CHClF2, and CHCl2F (1978)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 10 (1978), S. 1215-1223 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Using the ECR technique the electron scavenging properties of the halomethanes CHF3, CHClF2, and CHCl2F were investigated. A brief discussion is given on the evaluation of experimental data for inefficient polar scavengers. Absolute attachment rate constants were obtained from the decrease of the cyclotron resonance signal upon addition of the above scavengers. For the molecules CHF3 and CHCl2F the activation energies for the capture processes are given. Possible capture mechanisms are discussed.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550101204
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  • 9
    Electronic Resource
    Electronic Resource
    Kinetics of the thermal decomposition of bis-pentafluorosulfur trioxide(SF5O3SF5) in the presence of carbon monoxide (1979)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 11 (1979), S. 1089-1096 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermal decomposition of SF5O3SF5 in the presence of CO has been investigated between -9.8°C and + 9.9°C. Besides traces of S2F10, equimolecular amounts of SF5O2SF5 and CO2 are formed. \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm SF}_{\rm 5} {\rm O}_{\rm 3} {\rm SF}_{\rm 5} {\rm + CO } \to {\rm SF}_{\rm 5} {\rm O}_{\rm 2} {\rm SF}_{\rm 5} {\rm + CO}_{\rm 2}{\rm,}\Delta _n {\rm = 0} $$\end{document} The reaction is homogeneous. Its rate is proportional to the pressure of the trioxide and in dependent of the total pressure, the pressure of inert gases and of carbon monoxide: \documentclass{article}\pagestyle{empty}\begin{document}$$ - {\rm }\frac{{d[{\rm SF}_5 {\rm O}_{\rm 3} {\rm SF}_5 ]}}{{dt}}{\rm = +}\frac{{d[{\rm SF}_5{\rm O}_{\rm 2} {\rm SF}_5 }}{{dt}} = {\rm}k[{\rm SF}_5 {\rm O}_{\rm 3}{\rm SF}_5 ] $$\end{document} where k = k1∞ = 1016.32±0.40 exp(-25,300 ± 500 cal)/RT sec-1. Consequently, \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm D}_{{\rm SF}_{\rm 5} {\rm O - O}_{\rm 2} {\rm SF}_{\rm 5}} {\rm =}25.3{\rm}\pm {\rm 0}{\rm .5 kcal} $$\end{document} In the presence of oxygen a sensitized CO2 formation is observed. A mechanism is given which explains the experimental results.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550111007
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