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  • 1985-1989  (80)
  • Polymer and Materials Science  (50)
  • Chemical Engineering  (15)
  • Life and Medical Sciences  (12)
  • Maximum oxygen uptake  (3)
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Material
Years
Year
Keywords
  • 1
    Electronic Resource
    Electronic Resource
    The effects of previous severe exercise upon the respiratory $$\dot V_{CO_2 } /\dot V_{O_2 }$$ exchange ratio as a predictor of maximum oxygen uptake (1988)
    Springer
    European journal of applied physiology 57 (1988), S. 720-725 
    Details
    ISSN: 1439-6327
    Keywords: Respiratory $$\dot V_{CO_2 } /\dot V_{O_2 }$$ exchange ratio ; Maximum oxygen uptake ; Maximum exercise ; Prediction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The present study examined the effect of previous severe exercise upon (i) respiratory exchange during maximal exercise, and (ii) the respiratory $$\dot V_{CO_2 } /\dot V_{O_2 }$$ exchange ratio (R) as a predictor of maximum oxygen uptake ( $$\dot V_{O_{2\max } }$$ )- Thirteen healthy males performed a progressive treadmill test to $$\dot V_{O_{2\max } }$$ : at rest (T1); after a 1 h run on the level treadmill at a speed corresponding 82.4±7.3% of their $$\dot V_{O_{2\max } }$$ (T2); after 1 h recovery (T3); and after 24 h recovery (T4). Respiratory gases were continuously monitored. No changes in average work $$\dot V_{O_2 }$$ , $$\dot V_{O_{2\max } }$$ or maximum heart rate were found between trials. Average work $$\dot V_{CO_2 }$$ was lower in T2 (2.055±0.093 l·min−1,p〈0.001), T3 (2.080±0.087 l·min−1,p〈0.001) and T4 (2.337±0.154 l·min−1, NS) compared with T1 (2.360±0.147 l·min−1). This resulted in lower average R values in T2 (0.81±0.02,P〈0.001), T3 (0.83±0.02,P〈0.001) and T4 (0.94±0.02, NS) in relation to T1 (0.95±0.02). Analysis of the % $$\dot V_{O_{2\max } }$$ /R relationship over the final 5 min of each test showed a shift to the left during T2 (p〈0.001), T3 (p〈0.001) and T4 (NS) compared with T1. As a result predictions of $$\dot V_{O_{2\max } }$$ based on R ( $$\dot V_{O_{2\max } }$$ R) were similar to recorded $$\dot V_{O_{2\max } }$$ in T1 (+0.6%) and T4 (+2.2%). But higher in T2 (+8.7%,p〈0.001) and T3 (+6.9%,p〈0.001). The present results show that previous severe exercise can significantly affect respiratory exchange at rest and during maximum incremental exercise, and by doing so can significantly influence predictions of $$\dot V_{O_{2\max } }$$ based on R.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01075994
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  • 2
    Electronic Resource
    Electronic Resource
    The respiratory $$\dot V_{CO_2 } /\dot V_{O_2 }$$ exchange ratio during maximum exercise and its use as a predictor of maximum oxygen uptake (1988)
    Springer
    European journal of applied physiology 57 (1988), S. 714-719 
    Details
    ISSN: 1439-6327
    Keywords: Respiratory $$\dot V_{CO_2 } /\dot V_{O_2 }$$ exchange ratio ; Incremental exercise ; Treadmill ; Maximum oxygen uptake ; Prediction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The purpose of this study was to define carefully the dynamic relationship between oxygen uptake (as% $$\dot V_{O_{2\max } }$$ ) and the respiratory $$\dot V_{CO_2 } /\dot V_{O_2 }$$ exchange ratio (R) during maximum progressive treadmill exercise in trained and untrained men, and to determine if this relationship could be used to predict $$\dot V_{{\text{O}}_{{\text{2max}}} } $$ . Respiratory gases were continuously monitored and the % $$\dot V_{{\text{O}}_{{\text{2max}}} } $$ /R time profile calculated at 15 sec intervals over the final 5 min of each test. Young sedentary men (controls,n = 122) and over −60y sedentary men (n = 30) shared the same % $$\dot V_{{\text{O}}_{{\text{2max}}} } $$ /R relationship but the latter group had lower R values at $$\dot V_{{\text{O}}_{{\text{2max}}} } $$ (1.06±0.03 vs 1.08±0.03,P〈0.01) than controls. Endurance trained men (n = 45) had a lower % $$\dot V_{{\text{O}}_{{\text{2max}}} } $$ /R relationship and higher R at $$\dot V_{O_{2\max } }$$ (1.11±0.02,P〈 0.001), team athletes (n = 98) had a lower% $$\dot V_{O_{2\max } }$$ /R relationship but lower R at $$\dot V_{O_{2\max } }$$ (1.06±0.03,P〈0.001) and the weight trained (n = 19) had a higher% $$\dot V_{O_{2\max } }$$ /R relationship and lower R at $$\dot V_{O_{2\max } }$$ (1.01±0.02,P〈 0.001) all compared to controls. From the % $$\dot V_{O_{2\max } }$$ /R time profile, the following formulae were devised for the estimation of $$\dot V_{O_{2\max } }$$ ( $$\dot V_{O_{2\max } }$$ R): Young Sedentary, $$\dot V_{O_{2\max } }$$ R = $$\dot V_{O_2 }$$ R (3.000 −1.874 R); Over −60y Sedentary, $$\dot V_{O_{2\max } }$$ R = $$\dot V_{O_2 }$$ R (3.457-2.345 R); Endurance Trained, $$\dot V_{O_{2\max } }$$ = $$\dot V_{O_2 }$$ R (1.980–0.912 R); Team Athletes, $$\dot V_{O_{2\max } }$$ R = $$\dot V_{O_2 }$$ R (2.805−1.726 R); Weight Trained, $$\dot V_{O_{2\max } }$$ R = $$\dot V_{O_2 }$$ R (4.236−3.191 R). Comparison of recorded $$\dot V_{O_{2\max } }$$ and the estimated $$\dot V_{O_{2\max } }$$ R values showed no significant differences in any of the groups examined (r = 0.89–0.90,p〈 0.001). These results suggest the R response to maximum incremental exercise may be influenced by different types of physical training, and that specific formulae derived from the % $$\dot V_{O_{2\max } }$$ /R relationship can provide a precise estimate of $$\dot V_{O_{2\max } }$$ for individuals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01075993
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  • 3
    Electronic Resource
    Electronic Resource
    The effects of dietary manipulation upon the respiratory exchange ratio as a predictor of maximum oxygen uptake during fixed term maximal incremental exercise in man (1989)
    Springer
    European journal of applied physiology 58 (1989), S. 722-727 
    Details
    ISSN: 1439-6327
    Keywords: Respiratory exchange ratio ; Maximum oxygen uptake ; Dietary manipulation ; Maximal incremental exercise
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary This study examined the effects of dietary manipulation upon the respiratory exchange ratio ( $$R = \dot V_{{\text{CO}}_{\text{2}} } /\dot V_{{\text{O}}_{\text{2}} } $$ ) as a predictor of maximum oxygen uptake ( $$\dot V_{{\text{O}}_{{\text{2}} {\text{max}}} } $$ ). Seven healthy males performed fixed term maximal incremental treadmill exercise after an overnight fast on three separate occasions. The first test took place after the subjects had consumed their normal mixed diet (45±5% carbohydrate (CHO)) for a period of three days. This test protocol was then repeated after three days of a low CHO diet (3±2% CHO), and again after three days of a high CHO diet (61±5% CHO). Respiratory gases were continuously monitored during each test using an online system. No significant changes in mean exercise oxygen uptake ( $$\dot V_{{\text{O}}_{\text{2}} } $$ ), $$\dot V_{{\text{O}}_{{\text{2}} {\text{max}}} } $$ or maximum functional heart rate (FHRmax) were found between tests. Mean exercise carbon dioxide output ( $$\dot V_{{\text{CO}}_{\text{2}} } $$ ) and R were significantly lower than normal after the low CHO diet (bothp〈0.001) and significantly higher than normal after the high CHO diet (bothp〈0.05). Moreover, compared with the normal CHO diet, the R-time relationship during exercise was at all times significantly (p〈0.001) shifted to the right after the low CHO diet, and shifted to the left, being significantly so (p〈0.05) over the final 5 min of exercise, after the high CHO diet. As a result, predictions of $$\dot V_{{\text{O}}_{{\text{2}} {\text{max}}} } $$ based on the R-time relationship were similar to recorded $$\dot V_{{\text{O}}_{{\text{2}} {\text{max}}} } $$ after the normal CHO dietary condition (-1.5±1.9%), but higher after the low CHO diet (+14.8±3.9%,p〈0.001) and lower after the high CHO diet (−7.0±4.5%,p〈0.01). These results indicate that dietary manipulation can significantly affect respiratory gas exchanges during fixed term maximal incremental exercise, and by doing so can significantly influence predictions of $$\dot V_{{\text{O}}_{{\text{2}} {\text{max}}} } $$ based on R.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00637383
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    Paper (German National Licenses)
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  • 4
    Electronic Resource
    Electronic Resource
    Heat transfer effects on the processing-structure relationships of polyetheretherketone (PEEK) based composites (1988)
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 583-591 
    Details
    ISSN: 0032-3888
    Keywords: Chemistry ; Chemical Engineering
    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: An analytical methodology was developed capable of describing interrelations between thermal processing and polymer structure for thermoplastic based composite laminates. Specifically, this modeling methodology was used to describe experimental results generated with a specially designed match die quench mold by processing both neat PEEK polymer and carbon fiber reinforced laminate samples at different cooling rates. The developed model accurately predicted temperature profiles for PEEK laminates of different thicknesses, under normal as well as extreme quenching conditions of 114°C/s. surface cooling rates that are possible to generate with the quench mold. In general, the modeling methodology is capable of predicting a part's thermal profile during processing in terms of the composite's microscopic intrinsic properties (fiber and matrix), composition, and lamina orientation. Furthermore, by coupling to the thermal profile description, a previously developed crystallization kinetics model for PEEK polymer and its carbon reinforced composite, a quantitative description of structural development during processing was obtained. Thus, with this analytical methodology, a skin-core crystallinity profile, where the crystallinity varies with part-thickness as a result of uneven cooling experienced during processing, was predicted both for the neat PEEK polymer and its carbon reinforced laminate forms. Finally, the developed methodology clearly established the interplay of both microscopic heat transfer and kinetics of crystallization/solidification of the matrix that must be accounted for in predicting the final structure of a carbon fiber reinforced laminate that will, in turn, govern microscopic and macroscopic performance.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pen.760280907
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    Paper (German National Licenses)
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  • 5
    Electronic Resource
    Electronic Resource
    Fluid sorption characterization of PEEK matrices and composites (1988)
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 634-639 
    Details
    ISSN: 0032-3888
    Keywords: Chemistry ; Chemical Engineering
    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: Neat poly(ether-ether-ketone) (PEEK) and carbon fiber reinforced PEEK (APC-2) specimens were prepared using a variety of cooling rates to achieve a range of crystallinities. Amorphous specimens were exposed to a variety of fluids to determine the penetrant types which are able to strongly influence the material. This allowed the estimation of the solubility parameter and hydrogen bonding index for PEEK to be 9.5 and 3.1, respectively. Methylene chloride was used to investigate the kinetics of penetrant sorption. The data demonstrated Case II behavior, with the initial crystallinity having a pronounced effect on both the kinetic and equilibrium data. Accordingly, a model was proposed capable of describing the sorption level and penetration depth as a function of time given the sample crystallinity and sorption temperature. With Case II behavior there was no difference in the sorption kinetics of neat and fiber reinforced PEEK. Finally, the dynamic mechanical properties measured during sorption were found to be dependent on the sorption process.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pen.760280912
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  • 6
    Electronic Resource
    Electronic Resource
    Investigation on the microstructure of poly(cyclohexyl α-chloroacrylate)s using 500 MHz 1H and 25 MHz 13C NMR (1986)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 187 (1986), S. 375-381 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The tacticity of poly(cyclohexyl α-chloroacrylate) (PCCA) was studied by 500 MHz 1H and 25 MHz 13C NMR spectroscopy. The influence of the polymer configuration was observed at three different carbon resonances: The backbone methylene carbon, the carbonyl carbon and the quaternary carbon. Tetrad tacticities of PCCA measured from the resonance of the backbone methylene carbon were in good agreement with tetrad values obtained by 1H NMR. The polymer obtained was syndiotactic rich and obeyed Bernoullian statistics in its tacticity distribution.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1986.021870217
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  • 7
    Electronic Resource
    Electronic Resource
    Properties of polyacetylene obtained with (η-Cp)2Ti(PMe3)2 (1989)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 190 (1989), S. 1309-1317 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Acetylene was polymerized by (η-Cp)2Ti(PMe3)2 at room temperature to give predominantly trans-polyacetylene. All properties are within the ranges reported for polyacetylene produced with Ti(OBu)4/AlEt3 as catalyst.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1989.021900611
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  • 8
    Electronic Resource
    Electronic Resource
    Transport and related properties of paint films. II. Dynamic mechanical properties and humidity effects (1985)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 30 (1985), S. 111-133 
    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: A systematic four-stage investigation of eight unpigmented coating formulations, including three vinyl, two polyurethanes, and three epoxy systems was done to provide baseline structural information upon which an improved understanding and an optimization of protective coatings can be founded. First, the results from dynamic mechanical measurements are provided and discussed for the base polymer component in each coating system. Second, the effects of humidity on the dynamic mechanical properties of these base polymers were determined at room temperature. The extent of property degradation was monitored by calculating the Tg depression with increased humidity, assuming a temperature-humidity superposition. The extent of degradation, as monitored by the Tg, was found to correlate directly with the level of hydrogen bonding in these coatings. Third, the influence of typical coating additives (a TCP plasticizer and a rosin hardener) on the properties of two of the vinyl coating systems was investigated. In the final stage, the synergistic effects of absorbed moisture and these additives on the coatings properties were investigated at room temperature. Increases in the concentration of these additives was found to magnify the degradation effect of increased humidity. This magnified degradation has been assigned to increased water absorption with increases in the concentration of either of these additives.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1985.070300109
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  • 9
    Electronic Resource
    Electronic Resource
    Dielectric studies of the cure of epoxy matrix systems (1986)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 31 (1986), S. 1155-1167 
    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: Dielectric spectroscopy was used to monitor the curing process of two epoxy resin systems. The basic system (system I) consisted of DGEBA (a difunctional epoxy) and a polyamide in a 50-phr mixture. In addition, a comparative analysis was performed on a high-performance resin system (system II) used primarily in unidirectional composite applications. This system contained TGDDM (a tetrafunctional epoxy) and DDS (a tetrafunctional amine) in a 25-phr mixture. The dielectric data were obtained using a simple yet functional sample cell electrode designed and constructed in the laboratory. For system I, isothermal dielectric data were used to determine apparent activation energies for the temperature range from 22 to 70°C. The data showed that the activation energy was a function of temperature and increased as the temperature of the cure increased. This indicated that the reaction mechanism was also a function of temperature. For system II, data were collected between 140 and 190°C and an overall activation energy for that temperature range was determined. The overall activation energies for both systems, calculated using dielectric spectroscopy, compared favorably to those obtained using differential scanning calorimetry. Also, using a wider frequency range (240 Hz to 2 MHz), Argand diagrams were constructed and modeled with the Cole-Cole empirical equation for systems with a distribution of relaxation times. This justified the calculation of average relaxation times, which could then be related to the bulk physical properties of the polymer, such as viscosity. Modified Argand diagrams, where ε″ is plotted against ε′ at one frequency as a function of time, were also constructed, which aided in the understanding of the curing processes for these thermosetting systems.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1986.070310501
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  • 10
    Electronic Resource
    Electronic Resource
    Structure-property relationships in thermoplastic elastomers. IV. Dynamic mechanical relaxations in polydioxolane, polybutyltrioxocane, and poly(propylene oxide) polyurethanes (1988)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 36 (1988), S. 1387-1400 
    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: Dynamic mechanical measurements had been made on polyurethanes of a range of hard segment content (HSC) obtained from α,ω-dihydroxy derivatives of polydioxolane, polybutyltrioxocane, and poly(propylene oxide) of 2000-12,000 MW coupled with MDI and TDI with hydroxyethyl phthalamide chain extenders. N-methylated chain extender was used to investigate the effect of hydrogen bonding. A broad γ transition was observed between -100 and -115°C attributable to the local motion of methylene sequences with a distribution of relaxations. The β-transition between -55 and -72°C is influenced by the degree of hydration; the α-transition occurs at nearly the same temperatures for all the TPEs, independent of HSC and thermal history. The magnitude of the loss tangent peak is nearly proportional to the soft segment content; the peak corresponds to the glass transition. An α-transition at higher temperature is sensitive to the structure of soft segment, HSC, and thermal history. It is probably associated with the melting of some weakly ordered regions in the soft domain. The hard domain counterpart was observed at the next higher temperature as the ∊-relaxation. The final large loss of storage modulus occurs at temperatures much below the melting transition.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1988.070360610
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