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  • 1
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: trans-4,4,10-Trimethyl-9-decalone ( = trans-5,5,8a-trimethyl-octahydronaphthalen-1(2H)-one; 1), when treated with trifluoroperacetic acid, gave the unexpected hydroxyspirolactone 7-hydroxy-7,11,11-trimethyl-1-oxaspiro[5.5]undecan-2-one (6), in which the two new O-atoms were introduced in a 1,2-trans relationship. The structure of this compound was conclusively proven by X-ray crystallography. The process involves the intermediacy of 7-membered lactone 2, the expected Baeyer-Villiger product, which could also be successfully prepared under controlled conditions at 0° in a buffered medium containing Na2HPO4.
    Additional Material: 1 Ill.
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Materialwissenschaft und Werkstofftechnik 26 (1995), S. 147-147 
    ISSN: 0933-5137
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim [u.a.] : Wiley-Blackwell
    Materials and Corrosion/Werkstoffe und Korrosion 10 (1959), S. 281-304 
    ISSN: 0947-5117
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Fluates as binding media in the production of chemically resistant and capillary-tight cement and concrete1According to a new theoretical conception of the author, a clearer picture of the processes of hydration and hydraulic hardening in mortar was obtained as a result of obtaining an attack-resisting binder of the cement lime by means of a planned chemical transformation with fluates, and also through the clarification of their reaction mechanism; and this indicates new ways of determining the factors which influence chemical attack on concrete. By these means it was proved that the conventional view of these processes is not correct and must be critically re-examined.2Fluates contained in the mixing water cause a change in the mortar-like properties of the cement and improve working quality, strength capillary density and resistance to attack. Fluates are thus suitable ingredients for the production of resistant, dense cement-mortar and concrete; they influence its useful life and applications range.3Results of laboratory experiments are confirmed by manifold practical experience over long periods of observation. In view of this agreement of results the new knowledge is of fundamental practical and theoretical importance in the solution of the problem of attack on cement.
    Notes: 1Nach einer neuen zementtheoretischen Anschauung des Verfassers wurde durch die aggressionsbeständige Bindung des Kalkhydrats des Zements mittels einer gezielten chemischen Umsetzung durch Fluate und die Aufklärung ihres Reaktionsmechanismus eine vertiefte Vorstellung über die Vorgänge der Hydratation und der hydraulischen Erhärtung im Mörtelbett gewonnen und damit neue Wege zur Feststellung der die Betonaggression bestimmenden Einflußfaktoren aufgezeigt. Es konnte dadurch nachgewiesen werden, daß die bisherigen Anschauungen Über diese Vorgänge nicht zutreffen und einer kritischen Überprüfung unterzogen werden müssen.2Fluate im Anmachewasser bewirken eine Veränderung der mörteltechnischen Eigenschaften des Zements und verbessern dadurch Verarbeitbarkeit, Festigkeit, Kapillardichte und Aggressionsbeständigkeit. Demnach sind Fluate Zementwirkstoffe zur Herstellung von aggressivbeständigem, kapillardichtem Zementmörtel und Beton, wodurch deren Gebrauchsdauer und Anwendbarkeit entscheidend beeinflußt wird.2Laboratoriumsmäßige Untersuchungsergebnisse werden durch vielseitige praktische Erfahrungen nach langen Beobachtungszeiten bestätigt. Im Hinblick auf diese Übereinstimmung sind die neuen Erkenntnisse für die Lösung des Problems der Betonaggression theoretisch und praktisch von grundlegender Bedeutung.
    Additional Material: 18 Ill.
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  • 4
    ISSN: 0947-5117
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: On the Importance of the Hydrate of Lime in Cement Mortar an Concrete against Aggression and of its Resistant Setting by Chemical Reactions during Hydration1The evaluation and interpretation of analytic and physical long term experiments with concretes made of Portland and blast furnace cements which were stored in aggressive agents, shows that the results agree to the theory of cements of the author. On this basis the hydration and cementation processes in the mortar beds as well as the causes and the mechanism of the corrosion of concrete are discerned. As the results of several testing methods and of different evaluation principles are agreeing, theoretically, the experimental results are of general and principle importance.2By means of a chemical reation a resistant setting of the hydrate of lime in the liquid phase during hydration was made possible. The so caused inhibition of the primary aggression allowed to increase the resistance of concretes of standard cements to a level never achieved before.
    Notes: 1Durch die Auswertung und Deutung von Langzeitversuchen, analytischen und physikalischen Untersuchungsergebnissen mit Beton aus Portlandzement und Hochofenzement bei Lagerung in aggressiven Medien ist es gelungen, einc neue zementtheoretische Anschauung des Verfassers zu bestätigen und davon ausgehend zur Klärung der Hydratations- und Erhärtungsvorgänge im Mörtelbett sowohl als auch der Ursachen und des Verlaufs der Betonaggression beizutragen. Die Untersuchungsergebnisse sind im Himblick auf ihre Übereinstimmung nach verschiedenen Prüfmethoden und den verschiedensten Auswertungsunterlagen nach Herstellungsart und Durchführungszeit theoretisch von allgemeingültiger und grundsätzlicher Bedeutung.2Durch die aggressionsbeständige Bindung des Kalkhydrats des Zements in der flüssigen Phase durch eine gezielte chemische Umsetzung während der Hydratation und die dadurch verursachte Hemmung bzw. Stillegung der Primäraggression wurde es möglich, Beton aus Normenzementen auf einfache Weise eine Aggressionsbeständigkeit zu geben, wie sie bisher noch nicht erreicht werden konnte.
    Additional Material: 12 Ill.
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim [u.a.] : Wiley-Blackwell
    Materials and Corrosion/Werkstoffe und Korrosion 10 (1959), S. 739-760 
    ISSN: 0947-5117
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: On the causes and progress of aggression due to the attack of corrosive waters on cement mortar and concrete(First Communication)This First Communication presents a comparative synopsis of present knowledge and experience of the causes and progress of aggression, with special regard to recent developments, during the attack of corrosive waters on cement mortar and concrete, in as much as these are relevant to the causal relationship between cause and effect and to the processes during concrete corrosion in the mortar bed. This communication also deals with the different measures to enhance the corrosion resistence in concrete practice, and the influence of these measures on the concrete properties.
    Notes: In der 1. Mitteilung werden die bisherigen Erkenntnisse und Erfahrungen über die Ursachen und den Verlauf der Aggression unter besonderer Berücksichtigung neuerer Entwicklungen bei Einwirkung angreifender Wässer auf Zementmörtel und Beton, soweit diese im Hinblick auf den kausalen Zusammenhang zwischen Ursache und Wirkung und die Vorgänge bei der Betonaggression im Mörtelbett wesentlich sind, vergleichend zusammengefaßt und die verschiedenen Maßnahmen zur Erhöhung der Aggressionsbeständigkeit in der Betonpraxis und deren Einfluß auf die Betoneigenschaften behandelt.
    Additional Material: 8 Ill.
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  • 6
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 68 (1956), S. 414-414 
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Chemie in unserer Zeit 29 (1995), S. VIII 
    ISSN: 0009-2851
    Keywords: Chemistry ; Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 30 (1995), S. 324-332 
    ISSN: 1076-5174
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Early in the development of electrohydrodynamic mass spectrometry (EH-MS), it was realized that ion source performance improved when the sample liquid was supplied discontinuously to the capillary emitter. Based on this realization, an ion source was designed that operates without an external sample supply system. Its essential part is a metal capillary that serves both as the liquid reservoir and the field anode and is mounted exchangeably on a pushrod. As the liquid flow is field induced, the flow rates are extremely low, in the range of 0.2 nl min-1. Thus, in spite of high analyte concentrations needed, sample consumption is only a few picomoles per mass scan. Moreover, the emission of larger droplets is avoided, which contributes to the stability of the ion signal. As the capillary emitter is mounted on a standard emitter carrier known from field desorption (FD) MS, the new ion source is compatible with conventional FD ion sources. EH mass spectra of analytes could be obtained from substances whose solubility in glycerol was〉0.5 mol l-1. The substances investigated with the new ion source include sugars, amino acids, peptides and an antibiotic. The general characteristics of the mass spectra are essentially the same as those known from other EH ion sources. Besides abundant solvent cluster ions, only cationated or protonated molecules of the analytes could be detected, frequently with one or more solvent molecules attached to the ions. Fragment ions were not observed.
    Additional Material: 9 Ill.
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  • 10
    ISSN: 1076-5174
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Collision with neutral molecules is shown to provide a convenient method of adding internal energy to ions in a field-free drift region of the mass spectrometer. The effects on this process of ion accelerating potential, target gas pressure and identity, and precursor ion internal energy and mass have been investigated to optimize experimental conditions. Such collisions cause ion decompositions whose activation energies cover a broad range; for a particular ion such decompositions can be viewed as its “collisional activation (CA) spectrum.” CA spectra, which can be obtained for each ion in the normal mass spectrum, and which appear to follow the predictions of the quasi equilibrium theory, show many more of the possible unimolecular ion decomposition reactions for an ion than do unimolecular metastables, and thus provide valuable information for ion reaction mechanisms and molecular structure determination. Collisional activation can sometimes yield ion energies which are relatively inaccessible by electron impact. The precursor ion internal energy has a negligible effect on the ion's CA spectrum except for product ions formed through the processes of lowest activation energy. Thus, CA spectra should also be valuable for the characterization of ion structures.
    Additional Material: 14 Ill.
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