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  • 1983  (44,934)
  • 1960  (16,664)
  • 101
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    Bulletin of mathematical biology 45 (1983), S. 21-31 
    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Kinetic equations for the action of a reagent on a population which is increasing by Gompertzian growth are solved by a combination of analytical and numerical methods for both dilute distributions and cellular aggregates. For the aggregates an empirical function controlling extent of diffusion is used with external reagent concentration held constant, and the effective diminution of reagent activity caused by aggregation is related to the extent of penetration by diffusion. Diffusion from the centre is considered. Solutions with time-dependent reagent concentration are obtained for a distribution, and the effect of successive inputs of reagent studied.
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  • 102
    ISSN: 1522-9602
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    Topics: Biology , Mathematics
    Notes: Abstract Bilayer lipid membranes consist of an inner hydrocarbon tail region with the hydrophilic polar heads on either side. The order-disorder transition in the hydrocarbon tail reigon, from liquid crystalline (fluid) to gel state, is characterised in terms of a Landau-de Gennes description, in which the effect of an external electric field is incorporated through its description, in which the effect of an external electric field is incorporated through its interaction with the surface charges on the bilayer (placed as it is in an ionic medium) or with the polar heads. Biological implications of such a phase transition, for excitable membranes, resides in a model wherein ion channels (taken to be composed of protein bundles) are postulated to be surrounded by lipid molecules in the fluid phase when the membrane is in its resting state, while surface charges and/or the polar heads of the lipid molecules responding to an electric stimulus, if of adequate magnitude, induces a transition in the hydrocarbon tail region of the (boundary) lipid surrounding the ion channels from the liquid crystalline (fluid) to the crystalline (gel) phase which, in turn, through coupling with the relevant modes of the protein bundles, results in the opening of the ion channels, provinding thereby a mechanism for the desired response.
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  • 103
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    Bulletin of mathematical biology 45 (1983), S. 117-138 
    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Concepts of the uniqueness of the amino acid sequences of proteins were defined in a prior report (Saroff, H. A. and F. A. Kutyna. 1981. “The Uniqueness of Protein Sequences: A Monte Carlo Analysis.”Bull. math. Biol. 43, 619–639), which presented a detailed discussion ofi-uniqueness, i.e. the tendency of small peptides to be repeated within an amino acid sequence of a protein. We now report on the quantitative analysis ofo-uniqueness, which evaluates the tendency of small peptides to be repeated amongst different proteins, usually of a single species. A detailed analysis of theo-uniqueness of several proteins is presented to illustrate the method and the range of values encountered. Uniqueness data on sequences of human proteins in a data bank of sequences containing about 32,500 amino acids are made available in the form of a microfiche. Analysis of biologically active subsequences such as the angiotensins and the enkephalins suggest a tendency of the subsequences contributing to the property ofo-uniqueness to cluster in portions of the parent protein sequence which are biologically active. This property may provide a general method for predicting biologically active areas of proteins. Current data may already be adequate to permit useful predictions, and the rapidly accumulating and interrelated new data on nucleic acid and protein sequences will further enhance the power ofo-uniqueness analysis.
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  • 104
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    Bulletin of mathematical biology 45 (1983), S. 143-149 
    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract In this note we examine Eigen's nonlinear rate equations for the relation of coupled biomacromolecules. We obtain an exact solution to the equations for constant overall population densities and constant rate parameters. We conclude that there is only one stationary solution where all molecular species coexist when they are coupled by mutation.
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  • 105
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    Bulletin of mathematical biology 45 (1983), S. 229-237 
    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Previously developed light absorption models have treated the effective quantity of light-absorbing material within the experimental environment as a constant, i.e. a parameter. These models are, however, probabilistic in nature and are properly applied and interpreted only in a statistical sense. Thus, it is clearly logical to regard the effective quantity of light-absorbing material to be a random variable. In this paper an asymptotic distribution is derived for this random quantity, and it is shown how this distribution may be incorporated into present models. These results may be applied to light absorption by plant and crop canopies as well as to liquid or solid media. Furthermore, previous models are based upon the assumption that light is parallel, or effectively so, as for solar light. Such models may be inadequate for an artificial (laboratory) environment which utilizes point source light. Present models for estimating light interception and radiation intensity are modified so as to accommodate a proximate point source of light. Numerical examples are included to illustrate the theory.
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  • 106
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    Bulletin of mathematical biology 45 (1983), S. 239-257 
    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract This paper presents an exact analysis of a mutually coupled relay oscillator based on a method orignated by Tsypkin. Limit-cycle frequencies and phases can be determined exactly using this method, unlike other approximate methods based on describing functions and harmonic balance techniques. A new method of exact determination of limit-cycle stability is also shown to give excellent agreement with simulation studies. Different types of intercoupling are shown to give different stability conditions, and these are discussed in relation to gastrointestinal (GI) smooth muscle modelling. GI tract electrical activity has previously been modelled using bidirectionally coupled nonlinear oscillators, and the results of the present analysis of relay oscillators is compared with other studies using van der Pol dynamics.
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  • 107
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    Bulletin of mathematical biology 45 (1983), S. 269-285 
    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract Information about the way of branching of dendritic arborizations may be obtained by comparing the frequency distributions of observed branching patterns with theoretical distributions based on well-defined growth models. Two models usually get much attention in geomorphological and (neuro)biological studies, viz. terminal growth and segmental growth. Formulae to construct the exact probability distributions for both growth models are presented. It is shown that ranking and lumping of the individual branching patterns enable the analysis of very large arborizations with relatively few data. The application of the Kolmogorov goodness-of-fit test for discrete distributions to the analysis is discussed.
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  • 108
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    Bulletin of mathematical biology 45 (1983), S. 295-309 
    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract An autonomous system of two differential equations with an asymptotically stable steady state is considered. It is shown that there exists a class of time delays which preserves the stability of such a steady state. The charactristic return time (or decay rate) for the solutions to approach the steady state is estimated using the variational system for the perturbations.
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  • 109
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    Circuits, systems and signal processing 2 (1983), S. 77-87 
    ISSN: 1531-5878
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: Abstract In this paper we generalize recent theorems concerning the existence (and algorithms for obtaining) a power-series-type expansion for a nonlinear system's outputs in terms of its inputs. The results given here are directly applicable to a much larger class of systems.
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  • 110
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    Circuits, systems and signal processing 2 (1983), S. 119-128 
    ISSN: 1531-5878
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: Abstract Explicit conditions required to be satisfied by the numerator and denominator polynomial coefficients of a magnitude-squared rational response function, ¦S21(jωi, jω2) ¦2, so that it might approximate an ideal low-pass characteristic along any straight line in the plane through (0,0) in a maximally flat manner, are obtained. The condition for attenuation along all radial directions through (0,0) is expressed in terms of the positivity of a form in two variables. The technique is easily extended to the multidimensional case and can be used to design filters other than those of the low-pass type. The theory could be used to design lumped-distributed and variable-parameter filters.
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  • 111
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    Circuits, systems and signal processing 2 (1983), S. 179-192 
    ISSN: 1531-5878
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: Abstract Results are given concerning the existence and other properties of Volterralike input-output expansions for discrete-time systems whose inputs and outputs are defined on the time set {0,1,2,}. The results, which establish the existence of (and show how to obtain) a locally convergent input-output expansion for a very large class of systems, are along the lines of those reported recently by this writer for continuous-time systems. With regard to one of the theorems given here, new ground is broken in that the theorem directly addresses the case where the nonlinear part of the system need not be assumed to be memoryless. Systems of the kind considered arise, for example, in the area of communication channel modeling for digital data transmission.
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  • 112
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    Circuits, systems and signal processing 2 (1983), S. 259-268 
    ISSN: 1531-5878
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: Abstract Using fixed-point arguments, existence and uniqueness results are obtained for the joint resistance of infinite positive operator networks with noncommuting operators in the branches. Explicit representations for the joint resistance are given using the geometric mean of positive operators.
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  • 113
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    Circuits, systems and signal processing 2 (1983), S. 277-284 
    ISSN: 1531-5878
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: Abstract Convenient matrix formulas for calculating the sensitivities of multiplier coefficients of the impulse and step responses of arbitrary digital network configurations, as given by their flow graphs, are presented.
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  • 114
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    Circuits, systems and signal processing 2 (1983), S. 327-339 
    ISSN: 1531-5878
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: Abstract This paper presents new results for predictive compression of signal samples, based upon spectral observation. The formulation emphasizes the inherent presence of a deterministic signal model and will accommodate time-varying models and time- and signal-dependent error bounds. Transmission of predictive error residuals instead of the samples themselves is shown to be identical in structure to linear predictive coding; although additionally applicable where available stochastic signal models may be inadequate. Sample deletion, when prediction error is within a chosen bound, offers a real time compression method of particular importance to measurement and control applications.
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  • 115
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    Circuits, systems and signal processing 2 (1983), S. 445-467 
    ISSN: 1531-5878
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: Abstract This paper considers certain useful approximations which can be obtained by doubly terminated two-variable cascade-separable networks. Since such networks can be transformed into 2-D wave digital filters, these approximations provide useful magnitude responses in the 2-D digital domain, also. Two approximation methods are discussed, and these can produce near quadrantal symmetry.
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  • 116
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    European journal of wildlife research 29 (1983), S. 48-54 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary A full translation of Y Naw Helwriaeth is presented for the first time in German, and the contents, sources and significance of this old Welsh hunting code are discussed in detail. Y Naw Helwriaeth is a unique conflation of old Welsh, Anglo-Norman and Middle English sources, which was compiled in the mid sixteenth century byGruffudd Hiraethog.
    Abstract: Résumé Une traduction complète et fidèle en allemand du »Y Naw Helwriaeth« est présentée pour la première fois et le contenu, les sources et la signification de cet ancien code de chasse du Pays de Galles font l'objet d'une discussion approfondie. »Y Naw Helwriaeth« constitue une compilation unique d'éléments provenant de sources galloises anciennes, anglo-normandes et moyen-anglaises rassemblés au 17ème siècle parGruffudd Hiraethog.
    Notes: Zusammenfassung Eine vollständige und getreue Übersetzung von Y Naw Helwriaeth wird zum ersten Mal auf Deutsch vorgestellt, und der Inhalt, die Quellen und die Bedeutung dieses alten walisischen Jagdkodexes werden eingehend diskutiert. Y Naw Helwriaeth sind eine einzigartige Kompilation aus alten walisischen, anglo-normannischen und mittelenglischen Quellen, die mitten im 16. Jahrhundert vonGruffudd Hiraethog zusammengestellt wurde.
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  • 117
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    European journal of wildlife research 29 (1983), S. 62-62 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
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  • 118
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    European journal of wildlife research 29 (1983), S. 95-110 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary Rye, barley, potatoes, turnips and maize were cut back with scissors, by one-third and two-third to simulate browsing by game; in each case all plants in a plot were cut back by 30 % and 60 % respectively. In addition, the pulling-out of the plants by game was simulated, at rates of 80 %, 40 % and 20 %. Generally, in all cultivated plants, there were significant reductions of yield, almost exclusively in those plots in which 80 % of the plants had been removed. An influence on the ability of the plants to recover is exercised by the weather of the year and the timing of the damage. Analyses of the structure of the cereal crops showed that the influence on the stand density of the crop is greater than on the number of the heads per are or on the weight of 1000 heads.
    Abstract: Résumé Pour les besoins d'une simulation, du seigle, de l'orge, des plants de pommes de terre, des betteraves et du maïs furent recoupés aux 1/3 et aux 2/3 à raison de 30, 60 et 100 % des plantes d'une parcelle. En outre, on simula l'arrachage de plantes par le gibier à raison de 20, 40 et 80 %. Des pertes significatives furent généralement enregistrées parmi toutes les cultures dans les seules parcelles où 80 % des plantes avaient été écartées. La faculté de régénération des plantes est influencée par les conditions climatiques ayant prévalu au cours de l'année ainsi que par l'époque à laquelle les dégâts se sont situés. Des analyses de la récolte des céréales montrent que l'influence sur la densité des brinsest plus importante que sur le nombre de grains par are et par poids de mille grains.
    Notes: Zusammenfassung Roggen, Gerste, Kartoffeln, Rüben und Mais wurden zur Simulation des Wildverbisses mit Scheren um 1/3 und 2/3 zurückgeschnitten; jeweils alle Pflanzen, 60 % und 30 % der Pflanzen einer Parzelle. Zusätzlich wurde das Herausziehen der Pflanzen durch Wild simuliert, und zwar in den Stufen 80 %, 40 % und 20 %. Durchgehend in allen Kulturpflanzen zeigten sich signifikante Ertragsverluste fast ausschließlich in den Parzellen, in denen 80 % der Pflanzen entfernt worden waren. Einen Einfluß auf die Regenerationsfähigkeit der Pflanzen haben die Jahreswitterung und der Zeitpunkt des Schadens. Ertragsstrukturanalysen in Getreide zeigten, daß der Einfluß auf die Bestandesdichte größer ist als auf Kornzahl je Ähre und Tausendkorngewicht.
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    European journal of wildlife research 29 (1983), S. 120-122 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary A report is given on the occurrence of feral farm minks escaped from farms in Schleswig-Holstein. 230 captures, killings and sightings have been recorded since 1950. It is uncertain if there are already existing self-sustaining populations.
    Abstract: Résumé Des visons échappés d'élevages s'observent en parcours libre dans le Schleswig-Holstein depuis 1950. 230 captures, tirs ou observations ont été enregistrés jusqu'a présent. Il n'est pas établi clairement s'il existe pour autant des populations stables et autonomes.
    Notes: Zusammenfassung Entwichene Farmnerze kommen in Schleswig-Holstein seit 1950 im Freiland vor. 230 Fänge, Erlegungen und Beobachtungen wurden bisher registriert. Es ist unklar, ob bereits stabile, sich selbst erhaltende Populationen bestehen.
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  • 120
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    European journal of wildlife research 29 (1983), S. 111-119 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary Court hunting in the Dukedom of Westfalia in the time of the Electors of the House of Wittelsbach (1583–1761) required a large number of dogs talented and well-trained in many respects. Insofar as these were controlled by the staff of the Westfalian hunting office, the Electoral Oberkellner office in Arnsberg covered the maintenance of the pack. The costs amounted to around 3000 Reichstaler per year. In the course of the development of full state sovereignty, “dog-service” was introduced, involving around 90 farms, each of which either had to take and care for one of the Elector's dogs without payment or otherwise had to pay “dog-money” of 1 Reichstaler a year. Apart from farmers, the executioners and the bailiffs and several monasteries were also obliged to do “dog-service”, which in general was fulfilled by cash payments. The executioners paid 64 Reichstaler and the monasteries 252 Reichstaler a year. A particular form of “dog-service” was the dog-loan. Farmers and burghers were arbitrarily forced under threat of penalties to lend their dogs, insofar as they were suitable, to the hunts organized by the Elector or by the hunting office, without payment. Sporadic opposition to the “dog-service” had no success. It was only lifted, with all the other hunting burdens by a law, the Prussian Diocharge Act (Ablösungsgesetz) in 1850.
    Abstract: Résumé La chasse courtoise dans le Duché de Westphalie à l'époque des princes-électeurs de la Maison des Wittelsbach (1583–1761) exigeait un grand nombre de chiens aux dispositions variées et dressés de façon polyvalente. Dans la mesure où la conduite en était assurée par le personnel de chasse de Westphalie, l'entretien de ces chiens était pris en charge par l'intendance du prince-électeur d'Arnsberg. Les frais s'élevaient à quelque 3000 «Reichstaler» par an. Lors de l'instauration de la pleine souveraineté, 90 fermes furent tenues d'héberger chacune un chien seigneurial à titre gratuit ou sinon de s'acquitter d'une redevance annuelle d'1 «Reichstaler». En dehors des fermiers, le bourreau et son valet de même qu'une série de couvents étaient appelés à assurer une pension aux chiens, laquelle était le plus souvent monnayée: les bourreaux payaient 64 «Reichstaler», les couvents 252 «Reichtstaler» par an. Une servitude cynégétique particulière était constituée par le prêt de chiens. Fermiers et bourgeois étaient arbitrairement contraints sous la menace de sanctions, de mettre leurs chiens, à titre gratuit et pour autant qu'ils conviennent à cet usage, à la disposition de chasses organisées par le prince-électeur ou par ses services. Les protestations qui s'élevèrent de-ci de-là contre cette servitude restèrent sans effet. Ce n'est que lors de la promulgation de la loi prussienne de remplacement de 1850 que cette servitude ainsi que toutes les autres charges liées à la chasse furent abolies.
    Notes: Zusammenfassung Die höfische Jagd im Herzogtum Westfalen in der Zeit der Kurfürsten aus dem Hause Wittelsbach (1583–1761) erforderte eine große Zahl vielseitig veranlagter und ausgebildeter Hunde. Soweit diese durch das Personal des westfälischen Jagdamtes geführt wurden, bestritt die kurfürstliche Oberkellnerei in Arnsberg ihren Unterhalt. Die Kosten beliefen sich auf etwa 3000 Rtlr (Reichstaler) im Jahr. Im Zuge der Ausbildung der vollen Landeshoheit wurde die Hundelege eingeführt, von der etwa 90 Bauernhöfe betroffen waren, die entweder je einen kurfürstlichen Herrenhund unentgeltlich aufzunehmen und zu versorgen oder statt dessen ein Hundegeld von 1 Rtlr im Jahr zu zahlen hatten. Außer Bauern waren auch die Scharfrichter und Büttel sowie eine Reihe von Klöstern zum Hundedienst verpflichtet, der freilich im allgemeinen durch Geldzahlungen abgelöst wurde. Die Scharfrichter zahlten 64 Rtlr, die Klöster 252 Rtlr im Jahr. Eine besondere Form des Hundedienstes war die Hundeleihe. Bauern und Bürger wurden willkürlich unter Androhung von Strafen gezwungen, ihre Hunde, sofern sie dazu geeignet waren, zu den vom Kurfürsten oder vom Jagdamt abgehaltenen Jagden unentgeltlich herzuleihen. Vereinzelt sich regender Widerstand gegen den Hundedienst führte zu keinem Erfolg. Er wurde erst zusammen mit allen übrigen Jagdlasten durch das preußische Ablösungsgesetz von 1850 aufgehoben.
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    European journal of wildlife research 29 (1983), S. 130-130 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
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    European journal of wildlife research 29 (1983), S. 131-136 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
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    European journal of wildlife research 29 (1983), S. 137-142 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary The report deals with experiments on the beginning of reproductive capability of individually marked male and female fallow deer juveniles during the period 1979 to 1982. The animals lived as a juvenile group without any adults being present. The study revealed under the conditions of the experiment: 1.) male and female yearlings are as a general rule capable of reproduction at the age of 17 to 20 months; 2.) female yearlings who do not come into heat are weak individuals who are last in the line of priority, which is not pronounced in fallow deer; 3.) the reproduction activity takes place in the juvenile group without any obvious species-typical rutting behaviour; 4.) in 1 1/2 #x2013;2 1/2 year-old females, the reproductive period begins at the end of the 2nd third of November and lasts, as far as is known to date, until the end of the 2nd third of February. In a fallow deer group without adults there is no sharply limited rutting period: the reproductive period lasts at least 3 months; 5.) the late births to be seen again and again lie with the young females; 6.) 2–2 1/4 year-old females calving late require 2 further reproductive cycles until the calving time evens out at June; 7.) contrary to red deer, late calving fallow deer mothers can rear their calves successfully.
    Abstract: Résumé Sont présentées des recherches sur les débuts de l'activité de reproduction chez de jeunes daims mâles et femelles, marqués individuellement, au cours de la période 1979–1982. Les jeunes animaux vivaient entre eux en l'absence de sujets adultes. Dans les conditions de l'étude, les affirmations suivantes peuvent être avancées: 1. les yearlings mâles et femelles sont en état de se reproduire à partir de l'âge de 17 à 20 mois; 2. lorsque des yearlings femelles ne présentent pas d'oestrus, il s'agit de sujets faibles qui, dans la hiérarchie sociale — par ailleurs peu marquée chez le Daim-, occupent la dernière place; 3. l'activité génésique se déroule chez le groupe de juvéniles sans qu'apparaissent des comportements spécifiques du rut; 4. chez les femelles d'1 an 1/2 et de 2 ans 1/2, la période de reproduction débute à la fin de la 2ème décade de novembre et se poursuit, à notre connaissance, jusqu'à la fin de la 2ème décade de février; dans un groupe de daims sans sujets adultes il ne se présente pas de période de rut bien délimitée et la période de reproduction se prolonge pendant au moins 3 mois; 5. les mises bas tardives observées régulièrement chez le Daim sont à mettre au compte des femelles sub-adultes; 6. les femelles de 2 ans à 2 ans 1/4 aux mises bas tardives nécessitent 2 autres cycles de reproduction afin d'amener la période de mise bas à s'articuler autour du début juin; 7. contrairement au Cerf, les femelles du Daim dont la mise bas a été tardive sont à même d'élever leurs jeunes avec succès.
    Notes: Zusammenfassung Dargestellt werden Untersuchungen zum Beginn der Fortpflanzungsfähigkeit von individuell gekennzeichnetem jungem männlichem und weiblichem Damwild im Zeitraum von 1979 bis 1982. Die Tiere lebten als Jugendgruppe ohne Anwesenheit adulter Artgenossen. Die Studie ergab unter den Bedingungen des Versuches: 1.) weibliche und männliche Jährlinge sind im Alter von 17 bis 20 Monaten in der Regel fortpflanzungsfähig; 2.) wenn Jährlingsweibchen nicht in den Östrus kommen, handelt es sich um schwache Individuen, die in der beim Damwild an sich schwach ausgeprägten Rangordnung an letzter Stelle stehen; 3.) die Fortpflanzungsaktivität verläuft in der Jugendgruppe ohne deutlich erkennbare arttypische Brunftverhaltensweisen; 4.) bei 1 1/2- und 2 1/2 jährigen weiblichen Stücken beginnt die Fortpflanzungszeit am Ende des 2. Novemberdrittels und dauert, soweit bis jetzt bekannt, bis zum Ende des 2. Februardrittels. In einer Damwildgruppe ohne adulte Individuen gibt es keine zeitlich eng begrenzte Brunftperiode, die Fortpflanzungszeit dauert mindestens 3 Monate; 5.) die beim Damwild immer wieder beobachtbaren Spätgeburten gehen à conto der jungen weiblichen Stücke; 6.) spät setzende 2- bis 2 1/4 jährige Weibchen brauchen 2 weitere Fortpflanzungszyklen, bis die Setzzeit sich auf Juni eingependelt hat; 7.) im Gegensatz zu Rotwild können spätgebärende Damwildmütter ihre Kälber erfolgreich aufziehen.
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  • 124
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary This paper deals with the occurrence of five species of the genus Anser on Helgoland in the years 1962 to 1982. The actual status of each species is determined and observations from former years are added. In general, observations of geese on Helgoland have been increasing during recent years. Taking together all observations of the species, Geese are more common in autumn than in spring. Most observations date from October. The numbers of Bean Geese(Anser fabalis) on passage have been increasing since 1970, the yearly totals fluctuating considerably. Migration time lasts from the end of September to mid March. The numbers of resting individuals have been increasing likewise. The Pink-footed Goose(Anser brachyrhynchus) has not been recorded every year. Increasing numbers of single individuals can be seen resting on Helgoland. The White-fronted Goose(Anser albifrons) is a scarce species on Helgoland, nevertheless appearing in increasing numbers both on passage and as a resting species. The Grey-lag Goose(Anser anser) is the most common species of the genus Anser. Since 1972 the species has been increasing considerably, nowadays being recorded annually on passage. Grey-lag Geese can be observed every month. A peak of migration occurs in September/October and February/March. In general, the flight distance of resting Grey-lag Geese is decreasing. The Snow-Goose(Anser caerulescens) has been recorded only once on Helgoland.
    Abstract: Résumé Cette contribution est consacrée à la dispersion de 5 espèces d'Anséridés sur l'île d'Helgoland de 1962 à 1982. En complément du statut d'une espèce d'oie on fait état des observations recueillies au cours d'années antérieures. Dans l'ensemble, les observations d'oies sur Helgoland ont augmenté au cours des dernières années. Les totaux révèlent cependant des observations plus massives lors de la migration d'automne, c'est-à-dire en octobre. L'oie des moissons(Anser fabalis) présente une fréquence d'observation croissante depuis 1970 tout en manifestant de fortes variations numériques. Cette oie est observée de fin septembre jusqu'à mi-mars. Le stationnement de cette espèce sur Helgoland est également en augmentation depuis les dernières années. L'oie à bec court(Anser brachyrhynchus) n'est pas observée chaque année. Des individus isolés sont cependant observés de plus en plus fréquemment sur Helgoland. L'oie rieuse(Anser albifrons) s'observe rarement sur Helgoland. Toutefois, tant le passage migratoire que le stationnement de l'espèce montre une tendance à l'accroissement au cours des dernières années. L'oie cendrée(Anser anser) est l'espèce la plus fréquemment observée. Depuis 1972, l'accroissement de l'espèce est net et son passage migratoire s'observe tout au long de l'année avec une pointe en septembre-octobre et en février-mars. D'une façon générale, la distance de fuite des oies qui stationnent sur Helgoland diminue. L'oie des neiges(Anser caerulescens) n'a pu être observée qu'une seule fois sur l'île.
    Notes: Zusammenfassung In dieser Arbeit wird das Vorkommen von fünf Anser-Arten auf Helgoland von 1962–1982 beschrieben. Ergänzend zur Festlegung des Status einer Gänseart werden Beobachtungen früherer Jahre erwähnt. Allgemein haben die Gänsebeobachtungen auf Helgoland in den letzten Jahren zugenommen. In der Gesamtsumme aller Gänsebeobachtungen tritt der Herbstzug deutlicher in Erscheinung als der Frühjahrszug. Die meisten Gänsebeobachtungen fallen in den Oktober. Die Saatgans wird seit 1970 zunehmend beobachtet, schwankt aber stark in ihrem Vorkommen. Saatgänse werden von Ende September bis Mitte März auf Helgoland festgestellt. Das Rastvorkommen der Saatgans auf Helgoland steigt ebenfalls in den letzten Jahren. Die Kurzschnabelgans wird nicht alljährlich beobachtet. Einzeltiere werden zunehmend rastend auf Helgoland angetroffen. Die Bläßgans ist auf Helgoland selten. Sowohl das Zug- als auch das Rastvorkommen zeigt in den letzten Jahren allerdings eine zunehmende Tendenz. Die Graugans ist die am häufigsten beobachtete Anser-Art. Ab 1972 nimmt die Art deutlich zu. Die Graugans ist heute alljährlicher Durchzügler. Ihr Vorkommen verteilt sich über das ganze Jahr. Ein Zugmaximum liegt im September/Oktober und Februar/März.
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    European journal of wildlife research 29 (1983), S. 197-213 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
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    European journal of wildlife research 29 (1983), S. 244-247 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary On individually marked fallow dear stags (Dama dama L.), the activity of the alkaline phosphatase (AP) in the serum was examined from throwing of the spikes over 2½ years with 3 another cycles. It was thereby demonstrated that 1) the activity of the AP shows an obvious course over the periods of the year, 2) the peaks of activity over the periods of the year are clearly correlated with the 3 phases of antler formation, and 3) the level of maximum activity is related to the throwing weight of the antlers.
    Abstract: Résumé L'activité dans le sérum de la phosphatase alcaline (AP) depuis le rejet des dagues et tout au long des 2,5 années qui y ont fait suite (recouvrant 3 cycles de développement des bois) a été étudiée sur des daims (Dama dama L.) marqués individuellement. Il apparaît que (1) l'activité de l'AP présente un déroulement circannien caractérisé, (2) que les maxima annuels d'activité sont en corrélation avec les trois périodes de refait des bois et (3) que l'amplitude des variations est liée aux poids des mues.
    Notes: Zusammenfassung An individuell gekennzeichneten Damhirschen (Dama dama L.) wurde die Aktivität der Alkalischen Phosphatase (AP) im Serum vom Abwerfen der Spieße an über 2,5 Jahre hinweg mit 3 Geweihzyklen untersucht. Dabei zeigte sich, daß 1. die Aktivität der AP einen ausgeprägten jahresperiodischen Verlauf aufweist, 2. die jahresperiodischen Gipfel ihrer Aktivität deutlich mit den 3 Geweihbildungsphasen korrelieren und 3. die Höhe der Aktivitätsmaxima in Beziehung steht zum Abwurfgewicht der Geweihe.
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    European journal of wildlife research 29 (1983), S. 235-243 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary This report from the Forest Office Brilon, formerly Forest Office Bredelar, in the Sauerland, describes experiments on the effect of intense side-shoot gnawing in spruce on the growth of the spruce. The study covered the period 1968 to 1976. Six experiments were set up. In fenced enclosures of in each case roughly 450 m2 (fig. 1), measurements were made annually of the height of up to 16 plants. By way of comparison, up to 32 plants with intense gnawing of side shoots were measured (fig. 2). The results of the height measurements are shown in tables 1 to 6. The extent of the side-shoot gnawing in each case recorded. In all cases there was for at least 1 and for up to 8 years a significant difference between the length of growth on the plants inside the fence and outside the fence. It must therefore be drawn from this that intense gnawing of side-shoots, as was present in the research plot', leads to a reduction of growth. No answer can be given to the question of whether the reduction in growth balances out in later years. The superior growth on the shoots outside the fence for the experiments shown in tables 1 and 2 indicates that such a balancing is possible. The burdens which emerged during the experiment as a result of side-shoot gnawing are an indication of the fact that the roe-deer population was too high, i.e. that it was not supportable.
    Abstract: Résumé Il est rendu compte de recherches exécutées dans l'ancien cantonnement forestier de Brilon, dans le Sauerland (Rhénanie-Westphalie), sur les effets d'un abroutissement intense des pousses latérales sur la croissance en hauteur de l'Epicéa. Les observations se déroulèrent entre 1968 et 1976. Six dispositifs ont été installés. Dans une clôture mesurant chaque fois quelque 450 m2 de superficie (Fig. 1) la longueur des pousses terminales a été mesurée sur pas moins de 16 plants et, à titre comparatif, des mesures furent effectuées sur 32 plants qui subissaient des abroutissements prononcés des pousses latérales. Le résultat de ces mesures est présenté dans les Tableaux 1 à 6. L'intensité de l'abroutissement des pousses latérales est mentionnée à chaque reprise. Dans tous les dispositifs apparaît une différence significative — pendant une à huit années au moins — entre la hauteur des pousses terminales des plants situés sous et hors-clôture. Il en résulte qu'un abroutissement des pousses latérales, tel qu'il a été provoqué dans le cadre de ces essais, entraîne une diminution de la croissance en hauteur. La question de savoir si ce retard de croissance est récupéré par la suite reste ouverte. L'accroissement supérieur des pousses terminales à l'extérieur de la clôture pour les essais renseignés dans les Tableaux 1 et 2 semble indiquer qu'un tel rattrapage est possible. Les charges qui se sont manifestées au cours des essais par suite de l'abroutissement latéral constituent un indice comme quoi la densité de population de chevreuils était excessive et donc intolérable.
    Notes: Zusammenfassung Aus dem ehemaligen Forstamt Bredelar, heute Forstamt Brilon, im Sauerland in Nordrhein-Westfalen werden Versuche zur Auswirkung eines starken Seitentriebverbisses an Fichte auf das Höhenwachstum der Fichte dargestellt. Die Beobachtungen erstreckten sich über den Zeitraum von 1968 bis 1976. Sechs Versuche wurden angelegt. In einem Gatter von jeweils rund 450 m2 Größe (Abb. 1) erfolgten jährlich Messungen der Höhentriebe an bis zu 16 Pflanzen, zum Vergleich wurden bis zu 32 Pflanzen, die starken Seitentriebverbiß aufwiesen, vermessen (Abb. 2). Das Ergebnis der Höhentriebmessungen ist in den Tabellen 1 bis 6 dargestellt. Der Umfang des Seitentriebverbisses wird jeweils vermerkt. In allen Fällen trat für mindestens 1 und bis zu 8 Jahre ein signifikanter Unterschied der Länge der Höhentriebe für die Pflanzen im Gatter und außerhalb des Gatters auf. Gefolgert werden muß, daß starker Seitentriebverbiß, wie er bei der Versuchsanlage vorhanden war, zu einer Minderung des Höhenwachstums führt. Nicht beantwortet werden kann die Frage, ob die aufgetretene Verminderung des Höhenwachstums in späteren Jahren ausgeglichen wird. Das überlegene Wachstum der Höhentriebe außerhalb des Gatters für die in den Tabellen 1 und 2 nachgewiesenen Versuche spricht dafür, daß ein derartiger Ausgleich möglich ist. Die während des Versuches eingetretenen Belastungen durch Seitentriebverbiß sind ein Weiser dafür, daß der Rehwildbestand überhöht, d. h. auch nicht tragbar war.
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    ISSN: 1436-2449
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Summary A variety of primary and tertiary amino-telechelic polyisobutylenes have been synthesized quantitatively by various routes from alcohol-telechelic polyisobutylene. Thus the syntheses of α,ω-di(amino)-, α,ω-di-(N,N′-dimethylamino)-, and α,ω-di(N-phthalimido)polyisobutylenes have been achieved from α,ω-di(hydroxy)polyisobutylene with and without chain enlargement. Three different methods were used: an improved Gabriel synthesis, the reaction of ditosylester of α,ω-di(hydroxy)polyisobutylene with the potassium salt of unsubstituted and disubstituted ethanolamine, and the reduction of α,ω-di(cyanoethanol)polyisobutylene with LiAlH4 at room temperature. Analysis and characterization were done by gel permeation chromatography, IR and 1H-NMR spectroscopy.
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    Polymer bulletin 9 (1983), S. 5-10 
    ISSN: 1436-2449
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Summary A water soluble polyacrylic acid has been obtained by polymerization of acrylic acid initiated with silica-supported poly-γ-mercaptopropylsiloxane in the presence of water and carbon tetrachloride. A super absorbent sodium polyacrylate (water absorbing capacity 300 g/g) has been prepared by copolymerization of acrylic acid with a small amount of p-divinylbenzene with the same initiator in a mixture of aqueous sodium hydroxide solution, carbon tetrachloride, n-hexane and Tween 80.
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    Polymer bulletin 9 (1983), S. 33-39 
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    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Summary Electric conductance and transport numbers of polyions were measured in aqueous polystyrenesulfonate solutions having different counterions, at concentrations from 2×10−3 to ∼ 10−1 basemol dm−3. From experimental data the extent of atmospheric binding of small ions to polyions was derived. The resulting fraction of free counterions was found to agree within ±5% with the coefficient of self diffusion calculated according to the theory of Jackson, Lifson, and Coriell. The molar conductance and the effective charge of the polyion were applied for the calculation of the hydrodynamic friction coefficient related to a monomer unit of the polyion.
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    ISSN: 1436-2449
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    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Summary The thermoactivated relaxation processes resulting in untrapping of the carriers and in recombination luminescence are described by means of the sum of independent elementary relaxators. In order to describe an elementary relaxator distribution function following characteristics were obtained by the fractional glow technique: i) the mean activation energy, ii) the mean frequency factor, iii) the recombination intensity, iv) activation energy spectrum, v) and frequency factor spectrum for butadiene-styrene copolymer. Using the Boltzmann equation unusually large values of frequency factor and activation energy were obtained, giving evidence that molecular motions γ, α exist in some temperature regions and therefore, that another desciption would be necessary.
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    Polymer bulletin 9 (1983), S. 47-51 
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    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Summary A simple model for the concentration dependence of the electrical conductivity of the polymer electrolyte: poly(ethyleneoxide) — LiCF3SO3 is presented. It is assumed that the crystals with stoichiometry: 4 polymer oxygens to 1 lithiumion are insulating and the surrounding conducting solution is saturated in the 4∶1 crystals. Correcting the space available for conduction with a volume correction factor accounts qualitatively for the concentration dependence of the conductivity.
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    ISSN: 1436-2449
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    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Summary The fluorescence spectra of thin films of poly(N-vinylcarbazole), PVCA, were measured at temperatures between 103 K and 535 K by constant excitation light intensity. Below 300 K, the corrected spectra were divided into bands belonging to different emitting species of PVCA. Temperature changes of the intensity of fluorescence of the two main excitation energy traps in PVCA are discussed using the simplified kinetic model of Johnson. Local anomalies on the curves of intensity of excimer fluorescence versus temperature measured at constant wavelength reflex the γ- and δ- relaxation regions in PVCA.
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    Polymer bulletin 9 (1983), S. 60-66 
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    Notes: Summary The photoconductivity and thermostimulated currents were measured on amorphous and spherulitic layers of oligo(ethyleneoxy) 2,5-di(anilino)terephthalate. The crystalline domains in the amorphous phase form new traps, c. 0,6 eV deep.
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    Notes: Summary Reverse phase HPLC methods are elaborated for the characterisation of polyursthane elastomers. The quantitation of urethane groups after aminolysis, as well as the determination of basic hard segments and qualitative hard segments size distribution after hydrolysis in dimethylsulfoxid (DMSO) are described. The methods are ilustrated with diphenylmethane-p,p′-bis(4-octanoiloxybutylcarbamate) (U1) as model compound and three different polyurethane formulations.
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    Polymer bulletin 9 (1983), S. 67-74 
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    Notes: Summary Another representation of the chemical shift of the acceptor structural units' protons in the NMR spectra is proposed in order to make possible direct comparison between intramolecular complexation in intramolecular charge transfer complexes obtained by copolymerization. The influence of synthesis conditions and comonomer type on the intramolecular complexation is discussed.
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    Polymer bulletin 9 (1983), S. 85-89 
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    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Summary Shish-kebabs are observed by scanning electron microscopy on fracture surfaces of a low molecular weight, high-density polyethylene treated by hot pxylene. The shish-kebabs observed originate from the fibrils of the fracture surface. It is suggested that the larger fibrils are partially dissolved and that the partially dissolved molecules recrystallize on cooling forming the lamellar-like structures of the shish-kebabs. The less developed fibrils of the fracture surface dissolve completely.
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    Polymer bulletin 9 (1983), S. 75-80 
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    Notes: Summary The addition of 1 wt.% Al-stearate to the spinning-solution of ultra-high molecular weight polyethylene in paraffin-oil allows takeup speeds of the extrudate of 270 m/min. These as-spun filaments could still be hot-drawn, resulting in a tensile strength of 2.8 GPa. The overall draw ratio's encountered after spinning and hot-drawing are of the order of 1500 suggesting a resemblance between these flow phenomena and superplasticity.
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  • 139
    ISSN: 1436-2449
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    Notes: Summary Fractography by scanning electron microscopy (SEM) of samples of a low molecular weight, high-density polyethylene from the melt isothermally crystallized at 125°C, together with SEM on these samples treated with p-xylene (including fracture surfaces), polarized light microscopy, differential scanning calorimetry and gel permeation chromatography have provided evidence that fracture preferentially develops along a weakest link path defined by regions of segregated low molecular weight material. The segregated material is to a considerable extent accumulated in the spherulite boundaries.
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  • 140
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    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Summary In order to ascertain the role of mercaptan groups during grafting, the graft copolymerization of methyl methacrylate (MMA) onto reduced Indian Chokla Wool fibers in an aqueous medium was investigated using potassium peroxydiphosphate (PP) as initiator. The percentage of grafting was determined as a function of concentration of initiator PP, monomer MMA and sulfuric acid, time, temperature and the presence of solvents. The molecular weight of the grafted polymer decreased as the extent of grafting increased. A kinetic scheme was developed based upon the dependence of the rate of grafting upon the reactant concentrations.
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    Polymer bulletin 9 (1983), S. 98-105 
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    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Summary An activation analysis of relaxational β-transition in polymers, oligomers and simple molecular glasses has been made with the aid of DSC and the internal friction (IF) on the specimens under static load. On the basis of the results obtained, literature data and the correlations found, a conclusion has been drawn that β-transition in the linear polymers is defined by the rotation of the chain portion commensurable with Kuhn's segment as well as the intermolecular potential barriers.
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    Notes: Abstract The chemical modification of poly(vinyl chloroformate) and of its copolymers with compounds containing labile hydrogen atoms like amines, phenols, alcohols and 2-oxazolidone as well as with potassium cyanide and potassium fluoride has been investigated. Phase transfer catalysis conditions lead to soluble modified polymers with good substitution yields.
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    Polymer bulletin 9 (1983), S. 121-124 
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    Notes: Summary The efficiency of polyolefine melt stabilizer 2, 2′-thiobis-(4,6-di-tert.butylphenol) (I) as a hydroperoxide decomposing antioxidant was studied under model conditions.tert.Butylhydroperoxide was used to simulate the reaction with polypropylene hydroperoxide. The reaction was performed at 85°C in chlorobenzene solution. Decomposition of tert.butylhydroperoxide by I and formation of the sulphoxide II and the sulphone III from sulphide I were followed quantitatively. Formation of small amounts of effective peroxidolytic species from II or III, responsible for acceleration of hydroperoxide decomposition was considered.
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    Polymer bulletin 9 (1983), S. 125-131 
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    Notes: Summary The present paper describes two types of polymers with “hanging” β ketophosphonates groups. The first type was obtained by reacting carbanions of keto-phosphonates with chloromethylated polystyrene; the second one by reacting the same polymer with the tetramethylammonium salt of various β keto-phosphonates.
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  • 145
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    Notes: Summary The synthesis and characterization of linear telechelic polyisobutylenes having propargyl ether, propargyl ester and propiolic ester end groups are described. The syntheses were accomplished by reacting α, ω-di (hydroxy)-polyisobutylene with propargyl bromide or phthalic anhydride followed by propargylic alcohol or monopropargylic ester of phthalic acid chloride, or propiolic acid in the presence of different catalysts at room temperature (see Scheme 2). According to IR and 1H-NMR analyses quantitative conversions were obtained.
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    Polymer bulletin 9 (1983), S. 577-581 
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    Notes: Summary The copolymerization mechanism and the complexation properties of the copolymers of 9-anthrylmethylmethacrylate with acryloyl- β-hydroxyethyl-3.5-dinitrobenzoate and acryloyl-6-hydroxyhexyl-3.5-dinitrobenzoate are presented. The degree of complexation was found to increase by decreasing the difference between the side chain lengths and by increasing the flexibility of the main chain. The strength of complexation was estimated by considering the dependence of the chemical shifts of the aromatic protons on copolymer composition.
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    Polymer bulletin 9 (1983), S. 582-587 
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    Notes: Summary 13C-NMR studies of thermally treated polyphenylacetylenes (PPA) prepared with MoCl5 and WCl6 catalysts provide evidence for intramolecular cyclization and chain scission of both cis and trans polymers. The microstructures of thermally treated cis and trans PPA are different from the microstructure of trans PPA obtained by thermal isomerization during propagation.
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  • 148
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    Polymer bulletin 9 (1983), S. 588-592 
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    Notes: Summary Alternating copolymerizations of six-membered cyclic phosphonites as MN with lipoic acid as ME are described. The phosphonites employed were salicylyl phenyl phosphonite (SPO) and 2-phenyl-1,3,2-dioxaphosphorinane (trimethylene phenylphosphonite, TPO). The copolymerization took place without catalyst at 0°C or room temperature. The reaction of SPO with lipoic acid gave alternating copolymer 1, which was formed directly from a genetic zwitterion 4. On the other hand, the reaction of TPO with lipoic acid gave alternating copolymer 2, which was produced after a proton transfer as well as an O-S scrambling giving rise to units 2A and 2B, respectively. Both copolymers 1 and 2 have a lipoic acid component in the main chain.
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    Polymer bulletin 9 (1983), S. 593-597 
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    Notes: Summary Dilatometric measurements of n-Tetracosane from 330 K up to 420 K are reported. These experiments show evidence for a small kink in the specific volume — temperature curve. The correct statistical interpretation of the measured data yield a discret transition temperature above the melting point at about 378 K in close agreement with the results from other experimental methods.
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  • 150
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    Polymer bulletin 9 (1983), S. 186-189 
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    Notes: Summary Coexisting isotropic and anisotropic solutions of poly(n-octyl isocyanate)s (POIC) were prepared from parent polymers of increasing width of molecular weight distribution. In qualitative agreement with theoretical predictions, analysis of the coexisting phases indicates the efficiency of partitioning into said phases to increase with increased width of the distribution in the parent polymer.
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  • 152
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    Notes: Summary Acrylic acid (AA) forms a 1∶1 hydrogen-bonded complex with the repeating unit of poly(4-vinylpyridine) (P4VP) in dilute solution of methanol. The rate enhancement of the polymerization of AA in the presence of P4VP in methanol coincided with the viscosity change of the same system.
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  • 153
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    Notes: Summary Acidic copolymers of the poly(β-hydroxy-acid) type containing β-malic acid (hydrophilic) and β-malic acid benzyl ester (hydrophobic) repeating units in various proportions are prepared by two differentes routes : — catalytic hydrogenolysis of the benzyl ester bonds of homopoly(β-malic acid benzyl ester) and — chemical coupling of benzyl alcohol to poly(β-malic acid). In attempts to account for the route-dependence of the physico-chemical properties of resulting copolymers, GPC in aqueous medium and measurements of the solubility of Yellow OB, a lipophilic dye, in aqueous solutions have been carried out. The results are discussed in regard to the sequence distributions of hydrophilic and hydrophobic repeating units.
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  • 154
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    Notes: Abstract The effect of the molecular weight and the molecular weight distribution on the rheological properties of aqueous poly(ethylene oxide) (PEO) solutions has been investigated with four PEO samples differing in their Mw, Mw/Mn and purity. The main result of this study is that the steady shear viscosity as well as the complex dynamic viscosity of the samples with broad molecular weight distribution greatly differed from the viscosities of the samples having a narrow molecular weight distribution. Furthermore, the samples with broad molecular weight distribution showed a distinct molecular weight dependent non-Newtonian behavior at increasing shear rates and frequencies. This behavior was not observed for the sample with a narrow molecular weight distribution. Both effects are mainly attributed to the influence of the high molecular weight fraction in the PEO samples of broad molecular weight distribution. The often reported degradation of PEO solutions was not observed within the time scale of our experiment.
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    Polymer bulletin 9 (1983), S. 208-215 
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    Notes: Summary Glass transition temperature of polystyrene has been studied by D.S.C.. Glass transition, well known for macromolecules, has been observed up to the monomer. Measurements of the change in heat capacity ΔCp at Tg were carried out and a relationship between $$\frac{{\Delta Cp}}{T}$$ and $$\overline {Dp}$$ has been found. The results have been interpreted as a modification of interaction occuring at $$\overline {Dp}$$ ≃25.
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    Polymer bulletin 9 (1983), S. 216-222 
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    Polymer bulletin 9 (1983), S. 223-227 
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    Notes: Summary 14 systems of the stereospecific anionic butadiene/isoprene copolymerization were reinvestigated using the Kelen-Tüdős (KT) treatment of data. It was found that the classical binary copolymerization model holds for these systems, too; the level of error is relatively moderate and the reproducibility is better than in case of cationic copolymerizations.
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  • 158
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    Notes: Summary Copolymerizations of 1,1-diphenylethylene(DPE) with m- or p-divinylbenzene(DVB) were carried out in THF and toluene using alkyllithiums as initiators, and the monomer reactivity ratios were determined. The copolymers prepared in the presence of excess DPE over DVB had a highly alternating character and was harder to form a crosslinked polymer as compared with the homopolymer of DVB. The copolymer was treated with sec-C4H9Li in THF, and the resulting polyanion was reacted with several methacrylates to form the graft copolymers withpolymethacrylate branches.
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    Polymer bulletin 9 (1983), S. 236-240 
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    Notes: Abstract Blends of head to head polyisobutylene and amorphous head to tail polyisobutylene were prepared by casting films of the polymer mixtures from o-dichlorobenzene. The glass transition behavior of the polymer blends was studied by DSC analysis. Two glass transition temperatures were observed over almost the entire composition range which indicates that the two structurally similar head to tail and head to head polyisobutylenes are not miscible even in the molecular weight range of 3000 to 5000.
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    Polymer bulletin 9 (1983), S. 241-244 
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    Notes: Summary The tacticity of polymethacrylamide was studied by 1H and 13C NMR spectroscopy. It was found that the fractions of tactic triads could be determined from the resonances of α methyl and quaternary carbons and those of tactic pentad from the carbonyl carbon resonance. The polymer obtained with radical initiator was syndiotactic and the tacticity is consistent with the Bernoullian statistics.
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    Polymer bulletin 9 (1983), S. 245-251 
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    Notes: Summary The thermal behavior of a series of n-alkanes has been studied by means of a Mettler TA 2000 B heat flow differential scanning calorimeter. Between 450–480 K all n alkanes studied show an exothermic effect bound only to the first run and with hermetically sealed crucibles. The exothermic effect decreases with the mass of sample. If the crucible is sealed in an argon filled glove box, no effect occurs. On the contrary, if the experiment is carried out under oxygen a large exothermic effect is observed. We have concluded that the effect observed with sealed sample pans is not a phase transition but a slight oxydation of n alkanes.
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    Polymer bulletin 9 (1983), S. 254-254 
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    Notes: Summary An investigation is presented of the swelling, thermal and morphological characteristics of copolymers of methyl methacrylate and 1,3-bis-(methacryloxymethyl)-1,1,3,3-tetramethyl disiloxane. These materials were prepared by copolymerization/ crosslinking of the two monomers by gamma irradiation. Studies were performed on copolymers with mole fraction of the silicon-containing monomer ranging from 0.09 to 0.42.
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    Polymer bulletin 9 (1983), S. 260-267 
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    Notes: Summary The well-established data which gives a complex composition dependence for the relaxation of ethylene copolymers has been reexamined. Emphasis is placed on the β-transition. In the reanalysis of the data two new experimentally determined concepts are introduced. These are that this transition is definitely found in the homopolymer linear polyethylene, and that it is a reflection of segmental motions which take place within the interfacial region. With these principles it is possible to separate the β-transition from the glass temperature and thus explain the very unique composition relations.
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    Polymer bulletin 9 (1983), S. 268-275 
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    Notes: Abstract The use of 1-chlorodicyclopentadiene (DCp-Cl) as a minifer for the polymerization of isobutylene leading to asymmetric telechelic polymers having dicyclopentadienyl head groups and t-chloro tail groups, has been investigated. BCl3 is ineffective, however, diethylaluminum chloride was found to be a suitable coinitiator for the polymerization. According to kinetic investigations chain transfer to monomer is absent and DCp-Cl is an efficient minifer. Polymer characterization indicated a DCp functionality close to 1.0. The t-chloro functionality was 0.27, probably due to side reactions of the t-chloro group with the strong Lewis acids formed during the polymerization.
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    Polymer bulletin 9 (1983), S. 276-283 
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    Notes: Summary L-Lactic acid O-carboxyanhydride (L-Lac-OCA) was prepared by phosgenation of L-lactic acid lithium salt. Its polymerization was conducted using a variety of initiators, and the resulting poly(L-lactides) were characterized by 1H-and 13C-NMR spectra, by vapor pressure osmometry (VPO) and by optical rotation. Number average molecular weights 〉 3 000 were never obtained. Also polymerizations of D,L-Lac-OCA did not give higher Mn's. The formation of isotactic triads was favored under all conditions. Furthermore, copolymerizations of L-Lac-OCA and various α-amino acid N-carboxyanhydrides (NCAs) only yielded low molecular weight poly(depsipeptides). The polymerization mechanism is discussed.
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    Polymer bulletin 9 (1983), S. 284-291 
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    Notes: Summary 50.3 MHz 13C NMR cross-polymerization/magic angle spinning spectra of the raw silk of the mulberry silk moth (bombyx mori) and of crystalline silk fibroin were compared with those of synthetic copolypeptides of alanine and glycine. In crude silk, but not in crystalline fibroin , tyrosine, valine,aspartic acid and glutamic acid were detected in addition to alanine, glycine and serine. Furthermore, crude silk obviously contains ca. 10 % of an α-helix fraction which mainly consists of Ala-units. A small α-helix fraction (ca. 5 %) was also detected in the raw silk of the tussah silk moth (antheraea mylitta).
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    Notes: Summary The compositions of copolymers of butadiene (B) and isoprene (I), produced by anionic copolymerization with sec-butyl lithium initiator in hexane at 20–40°C gave a good fit at low conversions to the terminal model for copolymerization. Non-linear, “best estimates” of the reactivity ratios rB and rI were 2.82 and 0.42, 1.72 and 0.36, 2.18 and 0.35 at 20, 30 and 40°C. The rates of copolymerization at conversions up to 98% of total monomer gave a smooth relationship with the instantaneous feed composition, calculated using the terminal model, at each temperature and independent of the initial feed composition. These results are in accord with the terminal model being applicable to this anionic copolymerization from low to hiqh conversions.
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    Polymer bulletin 9 (1983), S. 299-304 
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    Notes: Summary The SiO2-supported TiCl4 catalyst was prepared by allowing SiO2 to react with TiCl4 in n-heptane. Then MgCl2 was supported onto this catalyst by treating a mixture of this catalyst and MgCl2·(THF)2 with AlEt2Cl in n-heptane. The SiO2-supported MgCl2/TiCl2 catalyst thus prepared showed a very high activity for the copolymerization of ethylene and propylene and gave a moderately random copolymer. A plausible model for the active species was proposed from the analytical results of the catalytic system.
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    Polymer bulletin 9 (1983), S. 313-320 
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    Notes: Summary Closed loop diagrams were obtained with ternary systems containing two interacting copolymers (styrene-4-vinylpyridine / styrene-methacrylic acid or methyl methacrylate-4-vinylpyridine / methyl methacrylate-methacrylic acid) and a solvent (dioxane or chloroform). Viscosimetric interaction parameters were determined in both solvents. Higher interactions in chloroform than in dioxane were evidenced from greater positive Δ b23. A single glass transition temperature obtained with the pair of copolymers of styrene-methacrylic acid / butyl methacrylate-4-vinylpyridine confirmed the compatibility of these copolymers in the solid state.
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    Notes: Summary Quasielastic light scattering measurements and pulsed field gradient NMR measurements have been made on poly(ethylene oxide) fractions in semi-dilute solutions. Similar measurements have been made on polystyrene in chloroform and toluene. Through suitable choice of sampling times, the QELS experiments allowed analysis of the “fast” and “slow” modes of relaxation in terms of the corresponding diffusion coefficients and their relative amplitudes. Comparison of the slow mode with self-diffusion shows that the former is between one and two orders of magnitude slower than self-diffusion which contrasts with a number of recent reports. Furthermore, the proportion of fast to slow modes is highly sensitive to temperature and concentration. It is concluded that the slow mode must involve a concerted pseudogel motion sensitive to polymer-polymer friction.
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    Polymer bulletin 9 (1983), S. 328-335 
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    Notes: Summary Optically active head-to-tail dimer and trimer of(S)-1,2-propanediol have been prepared by a step-wise synthetic procedure employing a strict chemical and stereochemical control, and by catalytic oligomerization of (R)-propylene oxide under anionic polymerization conditions .
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    Polymer bulletin 9 (1983), S. 321-327 
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    Notes: Summary The products from a 1,2,2,6,6-pentamethyl-piperidine have been identified both in photo-oxidizing polypropylene film and in model liquid phase photo-oxidations. In both cases, the tertiary amine is found to undergo attack by oxygen centered radicals at the N-methyl group and to generate the corresponding 2,2,6,6-tetramethylpiperidine in high yields. The latter can then take part in the cascade of protective reactions previously identified for secondary hindered amines.
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    Polymer bulletin 9 (1983), S. 336-343 
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    Notes: Summary A new series of chiral, structurally ordered polyesters containing mesogenic units and optically active spacers in the main chain has been prepared. A thermotropic liquid crystal polymorphism was found to occur and quite unusual twisted smectic and/or cholesteric mesophases are believed to exist.
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    Polymer bulletin 9 (1983), S. 344-347 
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    Notes: Summary We agree with Claudy and Létoffé that oxidation of hydrocarbons can occur in closed DSC pans because of entrapped O2. We do not find oxidation in open pans under flowing N2 unless dissolved O2 is present in the polymer. We report a Tu 〉 Tm in trans polyisoprene by DSC (open pan) and by dynamic mechanical loss. Our work supports the existence of the Tu transition of Krüger and coworkers.
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    Polymer bulletin 9 (1983), S. 349-354 
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    Notes: Summary The group VIB metal carbonyls were found to promote the polycondensation of benzyl halides when induced by heat. Their catalytic activity decreases in the order: Mo ≫ W 〉 Cr. Phosphine ligands attached to the metal poison the catalytic activity of the system. Species such as (CO)3M(PhCH 2 + )Cl− are considered to be active in promoting polymerization. The final polybenzyls have a branched, polycondensed structure of moderate molecular weight.
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    Polymer bulletin 9 (1983), S. 355-360 
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    Notes: Summary The radical cyclopolymerization of N,N′-dimethyl-N,N′-dimethacrylurea (DMDMU) was investigated. The resulting polymer was completely soluble in benzene, and was found to compose of a seven-membered cyclized unit by means of IR and NMR spectra. This observation indicated that this cyclopolymerization was performed with alternating inter-and intra-molecular head-to-head (h-h) propagations, i.e. h-h cyclopolymerization mechanism to give a h-h cyclopolymer. When the cyclopolymer was heated, it was found to convert to a h-h cyclopolymer of N-methyl-N,N-dimethacrylamide(MDMA). The hydrolysis of the cyclopolymers of DMDMU and MDMA to h-h polymethacrylic derivatives was not succeeded.
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    Polymer bulletin 9 (1983), S. 382-389 
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    Notes: Summary Rheo-optical FTIR spectroscopy has emerged as an extremely valuable tool to study deformation phenomena in polymeric solids. With the aid of a specially designed stretching apparatus short-time spectroscopic and mechanical data can be obtained simultaneously during the deformation and relaxation of polymers. Polyurethanes are particularly suited to such investigations because they contain functional groups with characteristic IR absorptions which can be assigned to specific domain locations of the polymer. Apart from a general introduction to the principle of the technique and its application to polyurethanes the data obtained with a series of three model polyester urethanes of different hard and soft segment content at ambient temperature are discussed in terms of the segmental orientation induced during uniaxial elongation and recovery.
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    Polymer bulletin 9 (1983), S. 361-368 
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    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Summary Composite curves of the viscoelastic functions may be obtained not only by the usual shift of isotherme data along the frequency axis, but also by a shift of the respective isochrones along the reciprocal temperature axis. This shift along the 1 / T axis is equivalent to that of the isochrones of dynamic viscosity, along the slope of zero shear apparent activation energy of flow. It is demonstrated that both types of shift are related to this zero shear activation energy of flow, so that an unique shift mechanism is effective in both cases. Isochrone based mastercurves are favourable for studies on polymer blends particularly, because the problematical choice of the reference temperatures of the components is circumvented.
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    Notes: Summary The effects of polyethyleneglycol (PEG) on the radical polymerizations of methyl methacrylate initiated with the aqueous solutions of such macromolecular electrolytes as sodium polyphenolate and sodium polycarboxylate were studied. PEG was found to promote the polymerizations initiated by such sodium salt-type's macromolecular electrolytes.
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    Polymer bulletin 9 (1983), S. 417-422 
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    Notes: Summary The copolymers obtained by the spontaneous reaction between 2-methyl-oxazoline (MN) and succinic anhydride (ME) are analyzed. The copolymerization takes place at 45 °C in CH3CN without added initiator. The composition of the copolymer was determined by 1H-NMR and 13C-NMR. The scheme of the copolymerization was presented. The genetic zwitterion is not the only species responsible for the propagation as it is deduced from the composition of the copolymers obtained, although its participation in the propagation is important.
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    Polymer bulletin 9 (1983), S. 410-416 
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    Notes: Summary Stress relaxation phenomena in polyamide 6 are presented in this paper. Tests were carried out on the tensile testing machine Fu 10 000e, using oar-shaped samples. Dependence of uniaxial stress changes in time, temperature or initial load was observed and measured. Analytical and mechanical models of stress relaxation in polyamide 6 were developed and are presented here.
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    Polymer bulletin 9 (1983), S. 423-428 
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    Notes: Summary Vinylchloride can be polymerized in THF by t-butylmagnesiumchloride as an initiator. Polymers obtained are free of carbon double bonds. Leading t-butyl as well as terminating -CH2-CH2Cl have been identified as end groups by C-13 nmr spectroscopy. According to the monomer/initiator ratio oligomers as well as high polymers have been prepared.
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    Meteorology and atmospheric physics 32 (1983), S. 53-57 
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    Description / Table of Contents: Zusammenfassung Etliche jüngst erhaltene, empirische Resultate und theoretische Untersuchungen der Abschätzung der thermischen Strahlung der Atmosphäre aus wolkenlosem Himmel werden diskutiert. Es wird gezeigt, daß des strahlungsmäßige Verhalten des Wasserdampfes bei Lufttemperaturen über dem Gefrierpunkt so gut als möglich und nötig parameterisiert worden ist, doch bei Temperaturen unterhalb des Gefrierpunktes sind noch Verbesserungen möglich. Zusätzlich wird gezeigt, daß Vorschriften zur genauen Berechnung der atmosphärischen Thermalstrahlung in der Lage sein müssen, die Effekte der zeitlichen und räumlichen Variabilität der Staubverteilung in Betracht zu ziehen.
    Notes: Summary Several recent empirical findings and theoretical developments related to the estimation of clear-sky atmospheric thermal radiation are discussed. It is demonstrated that the radiative behavior of water vapor at air temperatures above freezing has been parameterized as well as can or need be done, but that there may be room for some improvement at air temperatures below freezing. It is additionally shown that any procedure designed to accurately calculate atmospheric thermal radiation must be able to handle effects of airborne dust variability of both a temporal and spatial nature.
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    Meteorology and atmospheric physics 32 (1983), S. 1-22 
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    Description / Table of Contents: Zusammenfassung Die interannuale Veränderlichkeit in der Ausdehnung des antarktischen Meereseises wird während der winterlichen Zuwachsperiode (Juni bis September) für die fünf Jahre 1973–77 untersucht. Statistische Korrelationen zwischen den synoptischen atmosphärischen Zirkulationsverhältnissen, gegeben durch die Frequenz der von Satelliten beobachteten außertropischen Tiefdruckgebiete, und der breitenmäßigen. Ausdehnung des Meereseises werden auf hemisphärischer und regionaler Basis für jeden Winter ausgewertet. Markante Unterschiede in der winterlichen Zyklonentätigkeit begleiten die jährlichen Unterschiede im Wachstum und in der Ausdehnung des Eises, gemessen im zonalen Mittel, und sind besonders in den extremen Eiswintern 1973 und 1977 evident. Ein Zusammenhang zwischen der Ausdehnung des Meereseisgebietes während des Winters und der Frequenz von Zyklogenese ist besonders für die geographischen Breiten unmittelbar nördlich der Eisgrenze angedeutet. Drei Schlüsselgebiete starker interannualer Veränderlichkeit in den Eisbedingungen werden identifiziert und statistisch auf Rückwirkungen zwischen Eis und Zyklonen hin untersucht. Korrelationen zwischen der geographischen Breite des Eisrandes und der Zyklonenfrequenz zeigen die geringste interannuale Veränderlichkeit im ostantarktischen Sektor. Durch diese Gegebenheit wird die Rolle des semi-permaneten Tiefdruckzentrums im Wintereisregime dieser Region betont. Andererseits variiert die Korrelation zwischen Eis und Zyklonentätigkeit von Jahr zu Jahr bedeutend in der Weddellsee, wo die meeresbedingten Advektionsverhältnisse von zusätzlicher Bedeutung sind. Einzeluntersuchungen aus dem Zeitraum der fünf Winter dienen als Unterstützung der für jeden Sektor gewonnenen, statistischen Resultate.
    Notes: Summary Interannual variations in the extent of Antarctic sea ice are investigated for the winter growth season (June through September) for the five years 1973–77. Statistical correlations between the synoptic-scale atmospheric circulation, given by the frequencies of satellite-observed extratropical depressions, and the latitudinal extent of the ice are evaluated on hemispheric and regional scales for each winter. Marked differences in winter cyclone activity accompany the year-to-year variations in ice growth and extent on a zonally-averaged basis, and are particularly evident for the extreme ice winters of 1973 and 1977. A link between the expansion of the sea ice zone during winter and the frequencies of new cyclonic developments (cyclogenesis) is evident for latitudes immediately north of the ice-ocean boundary. Three key regions of high interannual variability in ice conditions are identified and examined statistically for ice-cyclone interactions. Correlations between ice-edge latitude and cyclone frequencies show least variation between years in the East Antarctic sector, emphasizing the role of the semi-permanent low pressure center in the winter ice regime of this region. Conversely, ice-cyclone correlations vary markedly from year-to-year in the Weddell Sea, where ocean-related ice advection patterns are of additional significance. Case studies from the five-winter period are used to support the statistical results obtained for each sector.
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    Meteorology and atmospheric physics 32 (1983), S. 99-107 
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    Description / Table of Contents: Zusammenfassung Die Ergebnisse der Untersuchung zeigen, daß in Jodhpur die Feuchtigkeit in kahlem sandigen Boden größer ist als in einem Boden unter einer Vegetationsdecke. Das mittlere Temperaturmaximum war in 5 cm Tiefe im allgemeinen um 1 bis 2°C höher als im Boden unter einer Vegetationsdecke, ausgenommen im Juh, wo eine beträchtliche Temperatur-abnahme im kahlen Boden eintrat. Die Tagestemperatur in 5 cm Tiefe war im Sommer höher als in tieferen Schichten, was zu einem abwärtsgerichteten Wärmefluß führte. Im Winter waren die Temperaturen in tieferen Schichten höher, was einen aufwärtsgerichteten Fluß von Wärme und Wasserdampf bewirkte. Es wurde eine große Veränderlichkeit des Wärmeflusses mit im allgemeinen positivem Fluß im Sommer und negativem Fluß im Winter beobachtet.
    Notes: Summary The results of the studies conducted during 1977–78 show higher moisture regime of a bare sandy soil of Jodhpur than the soil with vegetative cover. Mean maximum temperature of a bare soil at 5 cm depth, in general, was 1 to 2°C higher than the soil with vegetative cover except during July when there was considerable fall in temperature of a bare soil. Daytime soil temperatures at 5 cm depth during summer were higher than the lower depths leading thereby to downward movement of heat. In winter, however, the temperatures of lower layers were higher facilitating the upward flow of heat and the vapour flux. A high variability in heat fluxes with generally positive daytime heat fluxes in summer and negative in winter were observed.
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    Meteorology and atmospheric physics 32 (1983), S. 23-34 
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    Description / Table of Contents: Zusammenfassung Sorgfältig ausgewählte AMTEX-Daten wurden zur Berechnung von ähnlichkeitsfunktionen für die Parametrisierung des Oberflächen-Stress und des Wärmetransportes in der konvektiven atmosphärischen Grundschicht verwendet. Die ähnlichkeitsfunktionen für den Stress, die aus den über die Schicht gemittelten mittleren Windkomponenten bestimmt wurden, stimmen für den baroklinen Fall nicht mit ihren aus numerischen Modellen für den barotropen Fall bestimmten Gegenstücken überein, im Widerspruch zu dem, was wir von der Hypothese von Arya und Wyngaard [ 10] erwarten. Vielleicht waren die verwendeten Rawinsonden-Daten für die Verifikation dieser Hypothese nicht gut genug. Es wurde jedoch gefunden, daß die konvektive PBL-Höhe in übereinstimmung mit der Hypothese von Kazanski und Monin [6] mit dem Stabilitätsparameter gut korreliert ist.
    Notes: Summary Carefully selected AMTEX data were used to compute the similarity functions for the parameterization of the surface stress and heat flux for the convective atmospheric boundary layer. The similarity functions for the stress determined from the layer-averaged mean wind components for the baroclinic case don't agree with their counterparts predicted by numerical models for the barotropic case, contrary to what we expect from the hypothesis of Arya and Wyngaard [10]. Perhaps the rawinsonde data used in this study were not good enough for the verification of this hypothesis. However, the non-dimensionalized convective PBL height is found to be well correlated with the stability parameter in accordance with the Kazanski-Monin hypothesis [6].
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    Meteorology and atmospheric physics 32 (1983), S. 55-69 
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    Description / Table of Contents: Zusammenfassung Eine lineare, barokline Stabilitätsanalyse wird auf das vertikale, zonale Windprofil der Grundströmung vor der Bildung einer Depression während der MONEX-79-Phase in der Bucht von Bengalen angewendet, wobei ein quasi-geostrophisches, mehrschichtiges, numerisches Modell verwendet wird. Die aus der Zuwachsrate des Spektrums abgeleitete, bevorzugte Wellenlänge beträgt 1400 km für eine Kanalbreite von 1500 km und eine e-fache Vergrößerungszeit von 5.2 Tagen. Die vertikale Wellenstruktur wurde berechnet und mit der beobachteten Struktur der Depression verglichen. Beide besitzen mehrere gemeinsame Grundzüge. Die vertikale Struktur der bevorzugten Welle, aus einem modifizierten Windprofil abgeleitet, in dem die Windscherung unterhalb des Westwindmaximums entfernt wurde, zeigt bessere Übereinstimmung mit der Depressionsstruktur, als die aus dem vollen Windprofil erhaltene Struktur. Der Effekt der vertikalen Veränderlichkeit der statischen Stabilität in den unteren Schichten auf das Wachstum der kurzen, instabilen Wellen wird untersucht. Es zeigt sich, daß eine Abnahme der statischen Stabilität in den unteren Schichten zu einer Zunahme der Wachstumsrate und einer Abnahme der bevorzugten Wellenlänge führt.
    Notes: Summary A linear baroclinic stability analysis is performed for the basic vertical zonal wind profile prior to the formation of the depression during Bay of Bengal phase of MONEX-79 by utilizing a quasi- geostrophic, multilayer, numerical model. The preferred wavelength obtained from the growth rate spectrum is 1400 km for the channel width 1500 km, with an e-folding time 5.2 days. The wave structure in the vertical is computed and compared with the observed structure of the depression. Many common features are noticed between them. Further, the vertical structure of the preferred wave obtained from the modified wind profile, removing wind shear below the westerly maximum level, shows closer agreement to the depression structure than that obtained from the full profile. The effect of vertical variation of static stability in the lower layers on the growth of short unstable waves is studied. It is found that a decrease in static stability in the lower layers resulted in the increase in growth rate and decrease in the preferred wavelength.
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    Meteorology and atmospheric physics 32 (1983), S. 97-101 
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    Description / Table of Contents: Zusammenfassung In der Arbeit wird der Hintergrund des äquivalent barotropen Modells, wie es von Mahanti [6, 7, 8] eingeführt worden ist, im Detail besprochen.
    Notes: Summary The physical background of the equivalent barotropec model, introduced by Mahanti [6, 7, 8], has been discussed in details in the present study.
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    Meteorology and atmospheric physics 32 (1983), S. 161-185 
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    Description / Table of Contents: Zusammenfassung Bei der Modellierung mesoskaliger Küstenklimaeffete sind wegen des Übergangs Land-Meer, repräsentiert durch die Rauhigkeitslangez 0 =z 0 (x, y) und die WärmekapazitätC 0 =C 0 (x,y), und des verstärkten Einflusses der Feuchte ausgeprägte Inhomogenitaten zu berücksichtigen, welche die meteorologischen Verhältnisse signifikant mitgestalten. Mit Hilfe eines dreidimensionalen numerischen Modells werden in der vorliegenden Arbeit die Auswirkungen solcher horizontaler Inhomogenitaten auf Struktur und Variation der Grenzschicht in der Küstenregion studiert, Bowie die Entstehung von Advektionsnebel unter dem Einfluss unterschiedlicher geostrophischer Winde untersucht. Die Modifizierung der Windstärke und Windrichtung in ihrer Abhängigkeit von der Rauhigkeitslange und der unterschiedlichen thermischen Schichtung Bowie zwei Beispiele von Advektionsnebelbildung bei unterschiedlichem geostrophischem Wind werden als Ergebnisse vorgestellt.
    Notes: Summary When modelling mesoscale effects in the coastal climate we have to account for the significant influence of humidity and for the land-sea contrast which is represented by the roughness lengthz 0 =z 0(x, y) and the heat capacityC 0 =C 0 (x, y). This brings about strong horizontal inhomogenities which affect the meteorological situation significantly. The effects of these inhomogenities on the structure and variation of the boundary layer in the coastal region are studied by use of a three-dimensional numerical model; the formation process of advective fog in connection with different geostrophic winds is also investigated. As main results we present 1) the modifications of wind velocity and wind direction as a function of the roughness distribution and different thermal stratifications and 2) two simulations of advective fog formation assuming different geostrophic wind values in each example.
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    Meteorology and atmospheric physics 32 (1983), S. 201-218 
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    Description / Table of Contents: Zusammenfassung Statistische auf Andauer und Klimatologie begründete Modelle werden zur Vorhersage der Bahnen tropischer Zyklonen von der Nordwestküste Australiens her angewendet. Ein auf die Zeit 1980–81 bezogener Vergleich zeigt, daß eine Anpassung erster Ordnung nach kleinsten Quadraten von acht primären Vorhersagegrössen eine hohe Stufe statistischer Signifikanz hat und vergleichbare mittlere Fehler bei Vorhersagen auf Grund von Regressionsgleichungen höherer Ordnung gibt.
    Notes: Summary Statistical models based on persistence and climatology are used to forecast tropical cyclone tracks off the northwest coast of Australia. A comparison based on the 1980–81 season shows that a first order least squares fit of the eight primary predictors has a higher level of statistical significance and comparable mean forecast errors to predictions based on higher order regression equations.
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    Meteorology and atmospheric physics 32 (1983), S. 297-308 
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    Description / Table of Contents: Zusammenfassung Die asymptotische Form des Diffusionstensors in einer Scherungsströmung (im besonderen in einer Ekman-Strömung) wird auf eine zweidimensionale vertikal gemittelte Diffusionsgleichung mit einem Schwächungsterm erster Ordnung angewendet. Einige klassische Lösungen für punktförmige Quellen werden besprochen und auf ein Modell einer Scherungsströmung angewendet. Lösungen für nichtkonstante Quellen werden diskutiert, wobei der Effekt des Abschneidens des Diffusionsprozesses im hochfrequenten Bereich dargelegt wird. Eine einfache Anwendung auf experimentelle Daten in mesoskalem Abstand wird auch gezeigt.
    Notes: Summary The asymptotic form of the diffusivity tensor in shear flow (in particular Ekman flow) is applied to a two-dimensional, vertically averaged diffusion equation with a decay term of the first order. Some classical solutions for point sources are reviewed and applied to the shear flow model; solutions for non-constant sources are discussed, putting into evidence the cut-off effect of the diffusive process in the high frequency range. A simple application to experimental data on mesoscale distance is also shown.
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    Meteorology and atmospheric physics 32 (1983), S. 301-307 
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    Description / Table of Contents: Zusammenfassung Die vorliegende Arbeit gibt die Bedingung der Instabilität von Wellen mit unbegrenzter seitlicher Ausdehnung an. Es wird auch gezeigt, daß die obere atmosphärische kurze Welle der zonalen Wellenzahl 8 und die niedrige atmosphärische Zyklonenwelle beim Fehlen diabatischer Erwärmung instabil werden und zusammenbrechen.
    Notes: Summary The present paper gives a condition of instability of waves of infinite lateral extent. Also, it is shown that the upper atmospheric short wave of zonal wave number 8 and lower atmospheric cyclone scale wave become unstable and break down in the absence of diabatic heating.
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    Meteorology and atmospheric physics 32 (1983), S. 281-288 
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    Description / Table of Contents: Zusammenfassung Die täglichen Höhenwindbeobachtungsdaten, die von Schiffsbeobachtungen im MONEX-79 erhalten wurden, sind einer 2-D Filterung unterworfen worden, deren Reaktion hinsichtlich der Wellenzahl so ist, daß Wellen mit Wellenlängen kleiner als 760 km ausgefiltert wurden. Diese gefilterten Windkomponenten wurden „Wirbeln” zugeordnet. Die kinetische Energie dieser „Wirbel” in 3 Phasen des Monsuns, nämlich vor dem Beginn des Monsuns (Mai), zum Monsuneinsatz (Juni) und im vollentwickelten Monsun (Juli), wird untersucht. Es wurde festgestellt, dass der Beitrag dieser „Wirbel” zur kinetischen Energie des Gesamtwindes von einem Minimum von 15,5% in der Vormonsunzeit bis 40% in der Phase des voll entwickelten Monsuns variiert. Der Energieaustausch zwischen den „Wirbeln” und den grosskaligen Windkomponenten zeigt an, daß während der Phase des entwickelten Monsuns die untere Troposphäre bis 700 mb eine baroklin instabile Grundströmung zu haben scheint, während in den anderen Phasen die Grundströmung im allgemeinen barotrop instabil ist.
    Notes: Summary The daily upper-air wind data, obtained from the MONEX-79 ship observing platforms, are subjected to a 2-D filter, whose wavenumber response is such as to filter out waves having wavelengths less than 760 km. The filtered wind components are referred to as “eddies”. The kinetic energies of these eddies during the three phases of the monsoon, viz. (a) pre-onset (May), (b) onset (June), (c) established (July) are studied. It is found that the contribution to the kinetic energies of the total wind, by the eddies, vary from a minimum of about 15.5% during the pre-onset phase to a maximum of 40% during the established phase. The energy exchanges between the eddy and large-scale wind components, indicate that during the established phase the lower troposphere, upto 700 mb, appears to have a baroclinically unstable basic flow, while during the other phases, the basic flow is, in general, barotropically unstable.
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    Meteorology and atmospheric physics 32 (1983), S. 310-310 
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    Meteorology and atmospheric physics 32 (1983), S. 339-352 
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    Description / Table of Contents: Zusammenfassung Ein zeitabhängiges, auf den Grundgleichungen basierendes, numerisches Modell wurde verwendet, um die Hypothese zu prüfen, daß solare Veränderlichkeit eine Änderung in den Grundvariablen der oberen Atmosphäre und somit in der planetaren Langwellenstruktur der unteren Atmosphäre hervorrufen kann. Dieser Mechanismus wurde zur Erklärung einer offensichtlichen, atmosphärischen Reaktion auf solare Schwankungen herangezogen. Im Modell wird diese Veränderlichkeit durch eine diabatische Wärmequelle hervorgerufen, welche als eine einfache Repräsentation der Jouleschen Dissipationserwärmung angenommen wird. Die Langwellenstruktur der unteren Atmosphäre zeigte sich als unbeeinflußbar durch sonneninduzierte Vorgänge in der oberen Atmosphäre. Tatsächlich auftretende Veränderungen sind auf eine Distanz von 25 bis 40 km unterhalb des Niveaus maximaler Erwärmung beschränkt und sind von nur kurzer Lebensdauer.
    Notes: Summary A time-dependent, primitive-equation numerical model is used to test the hypothesis that solar variations induce changes in the distributions of basic state variables at high levels in the atmosphere, and thus induce changes in planetary-scale wave structure at lower atmospheric levels. This mechanism was proposed to explain apparent atmospheric responses to solar activity. The changes are brought about in the model by a diabatic heat source, which is taken to be a simple representation of Joule dissipative heating. Lower atmospheric wave structure is found to be insensitive to solar-induced changes in the upper atmosphere. Such changes as do occur are limited to within 25 to 40 km below the level of maximum heating, and are also quite short-lived.
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    Meteorology and atmospheric physics 32 (1983), S. 389-397 
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    Description / Table of Contents: Zusammenfassung Wir betrachten die Dynamik langer Wellen mit begrenzter Amplitude in einer quasigeostrophischen Atmosphäre. Es wird gezeigt, daß sie den von Charney und Drazin formulierten Theoremen für vertikale Reflexion und Verbindung mit der zonalen Strömung genügen. Es wird ferner gezeigt, daß der typische Effekt des kritischen Niveaus auch für solche Wellen gilt.
    Notes: Summary We consider the dynamics of finite amplitude long waves in a quasi-geostrophic atmosphere. It is shown that they satisfy the well known theorems, formulated by Charney and Drazin, for vertical reflection and coupling with zonal flow. It is further shown that the typical critical level effect holds for such waves as well.
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    Meteorology and atmospheric physics 32 (1983), S. 405-406 
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    Meteorology and atmospheric physics 32 (1983), S. 337-360 
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    Source: Springer Online Journal Archives 1860-2000
    Topics: Geography , Physics
    Description / Table of Contents: Zusammenfassung Die bodennahen nordhemisphärischen Temperaturvariationen 1881–1980 und einige in Frage kommende externe Einflußparameter werden statistisch untersucht. Die statistischen Maßzahlen und Tests jährlicher und jahreszeitlicher Daten zeigen, daß es sinnvoll ist, den tiefpaßgefilterten langfristigen Trend (T 〉 30 Jahre) vom verbleibenden hochpaßgefilterten Anteil zu trennen, wobei dieser weitgehend die Charakteristika einer stationären und vielleicht auch stochastischen Zeitreihe erfüllt. Der langfristige Trend muß jedoch als die nicht-stationäre Komponente angesehen werden, die vermutlich von externen Einflußmechanismen des Klimasystems gesteuert wird. Die spektral-statistischen Untersuchungen stützen dieses Konzept, weisen jedoch auch, wie die nicht-spektralen Untersuchungen, auf jahreszeitliche Besonderheiten hin. 84–91% des langfristigen (aber nur 38–65% des jährlichen) Anteils der Varianz lassen sich durch vulkanisch-solare Parameter sowie den beobachteten anthropogenen CO2-Anstieg erklären, wobei die Erfassung des solaren Einflusses sehr problematisch ist. Multiple lineare Korrelations- und Regressionsanalysen führen zu Abschätzungen der Signal-Amplituden und des Signal-Rausch-Verhältnisses. Neben dem vulkanischen und solaren Signal ist das CO2-Signal in den Jahresdaten, weniger signifikant in den Sommerdaten, auffindbar.
    Notes: Summary This is a statistical study on the northern hemisphere temperature variations near surface, 1881–1980, and some possible external forcing parameters. The statistical measures and tests of yearly and seasonal data indicate that it is reasonable to separate the low-pass filtered long-term trend (T 〉 30 years) from the remaining high-pass filtered quantity, where the latter fulfills closely the characteristics of a stationary may be stochastic time series. The long-term trend, however, has to be seen as the non-stationary component presumably driven by external forcing mechanisms of the climatic system. The spectral statistics maintain this concept; but there are, as in case of the non-spectral statistics, distinct seasonal peculiarities. 84–91% of the long-term (but only 38–65% of the yearly data's) variance can be explained by volcanic/solar parameters and the observed anthropogenic CO2 increase, where the solar influence, however, is very problematical to realize. A multiple linear correlation and regression analysis leads to assessments of the signal magnitudes and the signal to noise ratios. Besides the volcanic and solar signal, the CO2 signal is detectable in yearly and — less significant — in summer data.
    Type of Medium: Electronic Resource
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