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  • 1
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    Flow-through meter for the average power and energy of industrial laser installations (1986)
    Springer
    Details
    Publication Date: 1986-01-01
    Print ISSN: 1071-2836
    Electronic ISSN: 1573-8760
    Topics: Physics
    Published by Springer
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    PAPER CURRENT
  • 2
    Electronic Resource
    Electronic Resource
    Measurement facility for the relative radiation energy density distribution for pulse-periodic lasers (1988)
    Springer
    Measurement techniques 31 (1988), S. 966-967 
    Details
    ISSN: 1573-8906
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00864876
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    Paper (German National Licenses)
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  • 3
    Electronic Resource
    Electronic Resource
    Flow-through meter for the average power and energy of industrial laser installations (1986)
    Springer
    Journal of Russian laser research 7 (1986), S. 19-24 
    Details
    ISSN: 1573-8760
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The principle underlying the construction of a flow-through meter for average laser power and energy, its characteristic features, and the basis for choosing the principal system elements is described. The results of experimental investigations of the metrologic characteristics, the prospects of using the instrument, and possible ways of its upgrading are reported.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01120225
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  • 4
    Electronic Resource
    Electronic Resource
    Condensation polymers based on acenaphthene derivatives (1991)
    Weinheim : Wiley-Blackwell
    Acta Polymerica 42 (1991), S. 53-63 
    Details
    ISSN: 0323-7648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die Reaktionen von Acenaphthen und seinen Derivaten, die zur Synthese verschiedener Klassen von Monomeren, wie Bis(naphthalinsäureanhydriden), Bis(acenaphthochinolinen) und Bis(acenaphthylenen) mit unterschiedlichen Brükengruppen, führen, werden, betrachtel. Die synthetisierten Monomere erwiesen sich als geeignet zur Herstellung von Poly-(naphthalimiden), Poly(naphthoylenbenzimidazolen), Poly(chimoxalinen) und Poly(acenaphthylenen). Diese Polymere weisen sowohl gute thermische Eigenschaften als auch gute Verarbeitbarkeit auf.
    Notes: The reactions involving acenaphthene and its derivaties resulting in the synthesis of various classes of mononmers, namely, bis(naphthalic anhydride)s, bis(acenaphthoquinone)s, bis(acenaphthylene)s, containing various bridging groups, are considered. The synthesized monomers have been shown to be applicable for the preparation of poly-(naphthylimide)s, poly(naphthyoylenebenzimidazole)s, poly(quinoxaline)s, and poly(acenaphthylene)s combining good thermal characteristics and good processibility.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/actp.1991.010420202
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  • 5
    Electronic Resource
    Electronic Resource
    New bis(naphthalic anhydride)s with organoelement central groupings and poly(naphthaoylene benzimidazole)s on their basis (1991)
    Weinheim : Wiley-Blackwell
    Acta Polymerica 42 (1991), S. 63-66 
    Details
    ISSN: 0323-7648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Neue Bis(naphthalsäureanhydride) mit elemntorganischen Diphenylsilyl- und Carborangruppen wurden durch Wechselwirkung von Acenaphthen und Dichloranhydriden der entsprechenden dicarbonsäuren in einer Friedel-Crafts-Reaktion mit nachfolgender Oxidation des Bis(acenaphthyle) und Dehydratisierung der synthetisierten Tetracarbonsäuren erhalten. Die Reaktion der Anhydride mit Bis(o-phenyldiaminen) führte zu Poly(naphthyylenbenzimidazolen), die gute thermische Eigenschaften mit der Löslichkeit in organischen Lösungsmitteln in sich vereinigen und thermoreaktive Eigenschaften aufweisen.
    Notes: New bis(naphthalic anhydride)s with organoelement diphenylsilyl and m-carboranyl groups have been obtained by interaction of acenaphthene dichloroanhydrides of the respective dicarboxylic acids in Friedel-Crafts reaction followed by oxidation of the bis(acenaphthyl)s and anhydridization of the synthesized tetracarboxylic acids. Interaction of the anhydrides and bis(-o-phyenylenediamine)s yielded poly(naphthoylene benzimidazole)s, which combine good thermal characteristics with solubility in organic solvents and possess thermosetting properties.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/actp.1991.010420203
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  • 6
    Electronic Resource
    Electronic Resource
    New approaches to improve the thermal stability of polyquinoxalines (1988)
    Weinheim : Wiley-Blackwell
    Acta Polymerica 39 (1988), S. 455-459 
    Details
    ISSN: 0323-7648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Mit dem Ziel der Erhöhung der Wärmebeständigkeit von Polychinoxalinen wurde die Synthese von Poly(phenylchinoxalin-co-naphthoylenbenzimidazolen) durch katalytische Copolykondensation von Bis(o-phenylendiaminen) mit Bis(α-diketonen) und Bis(naphthalinsäureanhydriden) sowie einer Reihe von Phenylchinoxalin-Verbindungen mit Acenaphthylen-Gruppen durchgeführt. Durch Einwirkung höherer Temperaturen wurden daraus vernetzte, thermisch stabile Strukturen erhalten. Der Einfluß des Verhältnisses der Phenylchinoxalin-zu den Napthoylbenzimidazolringen auf die Eigenschaften der Copolymere wurde untersucht.
    Notes: In order to improve the thermal stability of poyquinoxalines, the synthesis of poly(phenylquinoxaline-co-naphthoy-lenebenzimidazoles) through catalytic copolycondensation of bis(o-phenylene diamines) with bis(α-diketones) and bis(naphthalic anhydrides) and of a number of phenylquinoxaline compounds with acenaphthylene groups capable of thermal hardening to give cross-linked thermally stable structures has been developed. The influence of the ratio of phenylquinoxaline and naphthoylene benzimidazole cycles on the fundamental properties of the copolymers has been studied.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/actp.1988.010390817
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  • 7
    Electronic Resource
    Electronic Resource
    Novel bis(napthalic anhydrides) and polyheteroarylenes on their basis (1988)
    Weinheim : Wiley-Blackwell
    Acta Polymerica 39 (1988), S. 460-464 
    Details
    ISSN: 0323-7648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Eine Reihe neuer Bis(naphthalincarbonsäureanhydride) wurden durch Umsatz von Acenaphthen mit Dichloranhydriden von Dicarbonsäuren unter den Bedingungen einer Friedel-Crafts-Reaktion mit Chloral bzw. Bromal und nachfolgender Oxidation der Bis(acenaphthyle) und Anhydridisierung der Tetracarbonsäuren synthetisiert. Aus diesen Anhydriden und Bis(o-phenylendiaminen) erhaltene Poly(naphthoylen-benzoimidazole) vereinen gute thermische Eigenschaften mit Löslichkeit in organischen Lösungsmitteln.
    Notes: A series of novel bis(naphthalic anhydrides) has been prepared through acenapthene interaction with the dichloroanhydrides of dicarboxylic acids under the conditions of the Friedel-Crafts reaction or with chloral and bromal followed by oxidation of bis-acenaphthyls and anhydrization of the tetracarboxylic acids synthesized. Poly(naphthoylene benzoimidazoles) combining advantageous thermal properties and solubility in organic solvents have been obtained through interaction between the synthesized anhydrides and bis(o-phenylene diamines).
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/actp.1988.010390818
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  • 8
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    Assessment of the efficiency of passive thermal protection system of rock massif (2021)
    Details
    Publication Date: 2021-10-21
    Description: The problem of ensuring the stability of rock mass is of particular importance in the conditions of thermal interaction of mine workings with permafrost rocks. The paper presents the results of studying the effectiveness of passive thermal protection system of permafrost massif. Based on a numerical modeling by use of ANSYS FLUENT software complex, studies of thermal interaction of a large-span chamber working and permafrost massif have been performed. On the example of a hypothetical three-dimensional model of mine working with different variations in the material composition of the protective structure (lining) of working and the use of convective heat transfer in the technological channel (air gap), it has been performed the calculated study of the features of the temperature regime of the lining structural elements. There has been carried the estimation of the predicted depth of thawing of rock depending on the design and material composition of the lining and the duration of the thermal impact on the rock massif. The influence of the thermal resistance of the mine working protective structure on the depth and dynamics of thawing rock massif has been studied, the structure determines the conditions of preservation of its cryogenic state and requirements for mining systems of regulation of the thermal regime. The temperature gradients formed in the structural elements of the lining, which can contribute to the occurrence of thermal stresses that have a negative impact on the stress-strain state of the protective structure of the mine working have been founded. On the example of the accepted model representations of the technological channel (temperature of the entering air, width of the channel) the weak influence of heat exchange due to free convection on the intensity of thermal interaction of the working and rock massif has been shown. To reduce the thermal impact on the protective structure of the mine working and the permafrost massif it is necessary to increase the intensity of heat exchange in the technological channel by decreasing the temperature of the air entering the channel, or using the forced convection based on the organization of a special ventilation system.
    Description: Проблема обеспечения устойчивости массива горных пород приобретает особое значение в условиях теплового взаимодействия горных выработок с многолетнемерзлыми горными породами. В статье представлены результаты изучения эффективности пассивной системы тепловой защиты породного массива криолитозоны. На основе численного моделирования с использованием программного комплекса ANSYS FLUENT выполнены исследования теплового взаимодействия большепролетной камерной выработки с массивом многолетнемерзлых горных пород. На примере гипотетической трехмерной модели горной выработки с различными вариациями материального состава защитной конструкции (обделки) выработки и использованием конвективного теплообмена в технологическом канале (воздушном зазоре) проведены расчетные исследования особенностей температурного режима конструктивных элементов обделки. Выполнена оценка прогнозируемой глубины оттаивания горной породы в зависимости от конструктивного исполнения и материального состава обделки и продолжительности теплового воздействия на породный массив. Изучено влияние термического сопротивления защитной конструкции горной выработки на глубину и динамику оттаивания породного массива, которая определяет условия сохранения его криогенного состояния и требования к горнотехническим системам регулирования теплового режима. Установлены температурные градиенты, формирующиеся в конструктивных элементах обделки, которые могут способствовать возникновению термических напряжений, оказывающих негативное влияние на напряженно-деформированное состояние защитной конструкции выработки. На примере принятых модельных представлений технологического канала (температура поступающего воздуха, ширина канала) показано слабое влияние теплообмена за счет свободной конвекции на интенсивность теплового взаимодействия горной выработки и породного массива. Для снижения теплового воздействия на защитную конструкцию горной выработки и массива многолетнемерзлых пород необходимо повышение интенсивности теплообмена в технологическом канале за счет понижения температуры воздуха, поступающего в канал, или использования вынужденной конвекции на основе организации специальной системы вентиляции.
    Description: Published
    Description: Refereed
    Keywords: Mathematical modeling ; Software complex ; Permafrost rocks ; Rock massif ; Chamber mine working ; Математическое моделирование ; Теплообмен ; Многолетнемерзлые горные породы ; Породный массив ; Камерная горная выработка ; ASFA_2015::M::Mining ; ASFA_2015::H::Heat transfer
    Repository Name: AquaDocs
    Type: Journal Contribution
    Format: pp.72-79
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