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  • 1970-1974  (30)
  • 1930-1934
  • Chemistry  (27)
  • paleontology  (2)
  • Bar Press Extinction  (1)
  • 1
    Electronic Resource
    Electronic Resource
    Hippocampal injections of magnesium pemoline and the extinction of a bar press response in rats (1972)
    Springer
    Psychopharmacology 27 (1972), S. 157-162 
    Details
    ISSN: 1432-2072
    Keywords: Hippocampus ; Magnesium Pemoline ; Memory ; Bar Press Extinction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Stainless steel cannulae were implanted in the medial hippocampus of 24 rats. The subjects were then trained to press a bar for milk reinforcement. After a fixed amount of training the animals were divided into four groups. A control group received injections of Holman's ringer (via the cannulae) while each of three experimental groups received a different dose of magnesium pemoline. The animals then performed an additional number of bar presses. Twenty-four hours later the time and number of bar presses to an extinction criterion were measured. The low and medium drug-dose group exhibited increased resistance to extinction. The results were discussed with regard to the effect magnesium pemoline has on performance variables and RNA synthesis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00439374
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  • 2
    Electronic Resource
    Electronic Resource
    Ontogeny of a Miocene pelecypod (1973)
    Springer
    Mathematical geology 5 (1973), S. 73-90 
    Details
    ISSN: 1573-8868
    Keywords: allometric equations ; correlation and regression ; principal-components analysis ; statistics ; allometric growth ; ontogeny ; paleontology ; relative growth
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Mathematics
    Notes: Abstract Relative growth of the Miocene pelecypod Glycymeris parilis (Conrad) was examined using allometric equations and principal components. Different parts of the shell showed contrasting growth strategies that were dictated by functional morphology and basic shell geometry. Despite the divergent developmental strategies, 93 percent of the correlation matrix variance is accounted for by overall size increase. The remaining variance mainly represents growth of the teeth, which differed considerably from other variables.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02114088
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    Paper (German National Licenses)
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  • 3
    Electronic Resource
    Electronic Resource
    The statistical zap versus the shotgun approach (1974)
    Springer
    Mathematical geology 6 (1974), S. 311-332 
    Details
    ISSN: 1573-8868
    Keywords: canonical correlation ; cluster analysis ; correlation ; discriminant analysis ; factor analysis ; multivariate analysis ; numerical taxonomy ; principal coordinates ; regression analysis ; statistics ; allometry ; eurypterids ; integration and coordination ; ontogeny ; paleontology ; relative growth
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Mathematics
    Notes: Abstract Multivariate analysis is used in the search for one or more types of structure. The statistical zap applies a single method to determine one preselected type of structure. Several zaps suffice to ascertain several types of structure. The statistical shotgun represents an alternative approach. Here, a series of methods is applied to the data with the intent of ascertaining all possible types of structure that may exist. If strong structure is present, an appropriate zap will probably reveal it, and a variety of techniques will determine the same general structure. If only the main structure is required, the zap is adequate. In this situation, the shotgun will display a basic consistency which is at least reassuring. However, zaps may fail to detect a more subtle secondary structure of geological interest which will be displayed by the shotgun. For weakly structured data, a zap will only determine one type of structure but the shotgun reveals all. Study of the ontogeny of Parastylonurus myops(Clarke), a Lower Silurian eurypterid from New York (USA) shows the virtues of the statistical shotgun.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02082354
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  • 4
    Electronic Resource
    Electronic Resource
    Poly(vinyl alcohol) hydrogels. Formation by electron beam irradiation of aqueous solutions and subsequent crystallization (1973)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 17 (1973), S. 3779-3794 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Aqueous solutions of poly(vinyl alcohol) were submitted to varying doses of electron beam irradiation. By modification of the classical Flory-Huggins equations appropriate to the initial state of solution of the polymer, the molecular weight between crosslinks, Mc, was calculated as a function of radiation dose, initial polymer concentration, and temperature. Following crosslinking in the solution state, crystallization was induced by dehydrating the network at temperatures above 90°C. Following dehydration, the polymer network was reequilibrated with water and its tensile properties compared with identically prepared hydrogels not subjected to crystallization by dehydration. Greatly enhanced values of ultimate tensile strength and resistance to tear result from the treatment producing crystallization, compared with those of the crosslinked but not previously dehydrated gels.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1973.070171219
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  • 5
    Electronic Resource
    Electronic Resource
    Kinetics studies in a continuous steady state hollow fiber membrane enzyme reactor (1974)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 16 (1974), S. 1113-1122 
    Details
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Porous hollow cellulose fibers have been used to separate a nonflowing enzyme solution of alkaline phosphatase from a continuous flow of substrate. The porosity of the hollow fiber membrane allows the substrate and product to diffuse freely through the membrane while restricting the permeation of the enzyme. The resulting “immobilized” enzyme system has been shown to behave as a continuous reactor - converting p-nitrophenylphosphate to p-nitrophenol. By varying the concentrations, flow rate, etc., either diffusion or enzyme kinetics can be studied. The continual influx of product and removal of substrate at steady state allows the study of kinetics of relatively short half-life enzymes and unstable systems.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260160811
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  • 6
    Electronic Resource
    Electronic Resource
    Kinetics of protein release from yeast sonicated in batch and flow systems at 20 kHz (1972)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 14 (1972), S. 33-42 
    Details
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The release constant, k, of brewers yeast sonicated at powers up to 200 W at 20 kHz has been shown to be independent of cell concentration up to values of 60 g made up to 100 ml. It is inversely proportional to the volume of the treatment vessel in the range 75 to 450 ml, and almost proportional to the input acoustic power from 60 to 195 acoustic watts. A flow system is described and a relationship linking protein release, flow rate, and the protein release constant, determined from batch experiments, is derived. Good agreement between the theoretical prediction of protein release and experimental results with the flow system was obtained.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260140105
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  • 7
    Electronic Resource
    Electronic Resource
    Optimization of the release of undegraded material extracted from cells by ultrasound (1974)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 16 (1974), S. 659-673 
    Details
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The time course of release of intact labile material from cells by cavitating ultrasound is examined. Curves are presented which show the yield of intact subcellular components obtainable from cells as a function of sonication time for various values of the ratio of inactivation rate to release rate. The general cases where inactivation of released product is concentration dependent (chemical) and concentration independent (mechanical) are considered.For a flow system the time of attainment of equilibrium concentration of active product is analyzed as a function of flow rate, release rate, inactivation rate, and volume of chamber. Curves of optimal yields to be expected for batch and flow systems are presented. It is shown that sonochemical inactivation can be made negligible by sonication of high cell concentration suspensions.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260160508
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  • 8
    Electronic Resource
    Electronic Resource
    Birefringent flow visualization of transitional flow phenomena in an isosceles triangular duct (1970)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 16 (1970), S. 483-489 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A flow visualization study was made with an optically birefringent solution of milling yellow dye in water flowing through a transparent duct of isoceles triangular cross section. The present data confirm a number of theoretical predictions concerning transitional phenomena in triangular ducts. One of the most interesting of these phenomena is the existence of a region of simultaneous laminar and turbulent flow in the duct. The present results, which agree with the theory, indicate an order of laminar and turbulent flow which is inverse to previous observations made with smoke filament tracings.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690160328
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  • 9
    Electronic Resource
    Electronic Resource
    The effect of Lewis number on the stability of a catalytic reaction (1970)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 16 (1970), S. 620-625 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: An extensive numerical study was carried out to determine the effect of Lewis number on the stability of a chemical reaction occurring inside a porous catalyst pellet. It is found that when the Lewis number is different from 1, the coupling between the concentration and temperature causes several pathological effects during the transient periods. One of the most interesting phenomenon is the occurrence of a unique unstable steady state with a periodic appearance of a very hot spot.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690160419
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  • 10
    Electronic Resource
    Electronic Resource
    An experimental evaluation of Kalman filtering (1973)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 19 (1973), S. 901-909 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The effectiveness of the stationary form of the discrete Kalman filter for state estimation in noisy process systems was demonstrated by simulated and experimental tests on a pilot plant evaporator. The filter was incorporated into a multivariable, computer control system and resulted in good control despite process and/or measurement noise levels of 10%. The results were significantly better than those obtained when the Kalman filter was omitted or replaced by conventional exponential filters. In this application the standard Kalman filter was reasonably insensitive to incorrect estimates of initial conditions or noise statistics and to errors in model parameters. The filter estimates were sensitive to unmeasured process disturbances. However this sensitivity could be reduced by treating the noise covariance matrices R and Q as design parameters rather than noise statistics and selecting values which result in increased weighting of the process measurements relative to the calculated model states.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690190503
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