Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 2020-2024
  • 1980-1984  (28)
  • 1910-1914
  • Chemistry  (26)
  • Chemical Engineering  (5)
  • stressful life events  (2)
  • 1
    ISSN: 1573-3521
    Keywords: stressful life events ; daily hassles ; daily uplifts ; psychological symptoms ; emotion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Psychology
    Notes: Abstract The standard life events methodology for the prediction of psychological symptoms was compared with one focusing on relatively minor events, namely, the hassles and uplifts of everyday life. Hassles and Uplifts Scales were constructed and administered once a month for 10 consecutive months to a community sample of middle-aged adults. It was found that the Hassles Scale was a better predictor of concurrent and subsequent psychological symptoms than were the life events scores, and that the scale shared most of the variance in symptoms accounted for by life events. When the effects of life events scores were removed, hassles and symptoms remained significantly correlated. Uplifts were positively related to symptoms for women but not for men. Hassles and uplifts were also shown to be related, although only modestly so, to positive and negative affect, thus providing discriminate validation for hassles and uplifts in comparison to measures of emotion. It was concluded that the assessment of daily hassles and uplifts may be a better approach to the prediction of adaptational outcomes than the usual life events approach.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Journal of behavioral medicine 4 (1981), S. 381-406 
    ISSN: 1573-3521
    Keywords: social support ; stressful life events ; psychological symptoms ; morale ; health status
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Psychology
    Notes: Abstract Social support research has been hampered by a lack of clarity both in the definitions of social support and in the conceptualization of its effects on health outcomes. The present study compared social network size and three types of perceived social support—tangible, emotional, and informational —in relation to stressful life events, psychological symptoms and morale, and physical health status in a sample of 100 persons 45–64 years old. Social network size was empirically separable from, though correlated with, perceived social support and had a weaker overall relationship to outcomes than did support. Low tangible support and emotional support, in addition to certain life events, were independently related to depression and negative morale; informational support was associated with positive morale. Neither social support nor stressful life events were associated with physical health. It was concluded that social support research would benefit from attention to the multidimensionality of support and greater specificity in hypotheses about the relationship between types of support and adaptational outcomes.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Poly(propylene) has been oxidized at temperatures between 240 and 289°C. The products were GC separated and on-line identified by an interfaced GC peak identification system. The major products are CO2, H2O, acetaldehyde, acetone, butanal, formaldehyde, methanol and other ketones and aldehydes. Most of the products can be accounted for by well-known reactions of alkoxyl and peroxyl radicals; the major products are derived from the secondary alkoxy and peroxy species. Oxygen starvation is manifested in diffusion limited products of olefins and dienes, and the increase of CO2 and H2O formation in pure oxygen atmosphere. The first order rate constant at 240°C is 2,4·10-3 S-1 with an overall activation energy of ca. 16 kcal·mol-1 (67 kJ·mol-1). If one assumes the oxidative pyrolysis to share the same reaction pathways as autoxidation at lower temperatures, then the observed rate constants and activation energy may be calculated from kinetic parameters measured earlier for autoxidation of poly(propylene) from 71 to 140°C. Good agreement was obtained implying a similarity of oxidative degradation of the polymers spanning a large temperature range.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 27 (1982), S. 3067-3077 
    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 perturbation chromatography apparatus has been designed and constructed for determining the vapor-liquid equilibrium between a two-component (solvent/helium) vapor phase and a two-component (polymer/solvent) liquid phase. The apparatus performed very well, giving reproducible and reliable results that agree with independent, previously reported studies. All tests of the equipment indicated that it was successful in meeting the conditions of low column pressure drop, small perturbations, and slow flow rate that are required for perturbation chromatography. Binary polymer/solvent data were obtained for polybutadiene (PBD)/benzene or polybutadiene/cyclohexane systems at solvent partial pressures to 40 kPa and for n-hexane at infinite dilution, all at the three temperatures of 333.15, 355.00, and 373.15 K. The experimental data for each system can be represented within experimental error by the Flory-Huggins polymer solution theory using a single binary interaction parameter that is independent of temperature and concentration.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 24 (1982), S. 1225-1231 
    ISSN: 0006-3592
    Keywords: Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 26 (1980), S. 678-680 
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 26 (1980), S. 935-943 
    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 detailed mathematical model of a single catalyst pellet has been developed to describe its behavior under transient conditions encountered during the warmup period of automobile exhaust catalytic converters. In contrast to the converter models previously reported in the literature, this model is capable of describing the time-dependent behavior of a composite catalyst pellet, and thus provides a convenient means of examining the effects of poison penetration and various noble metal impregnation strategies in the activity-time (rather than activity-temperature) domain.Extensive calculations were carried out to investigate the effects of various catalyst design parameters and converter operating conditions on the lightoff behavior of a spherical, platinum-alumina catalyst pellet. Due to the complex kinetics of the CO and hydrocarbon oxidation reactions, catalyst lightoff was found to exhibit interesting behavior with respect to variations of the system's design parameters and operating conditions. Graphs are presented to illustrate the parameteric sensitivity of these effects.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Biopolymers 21 (1982), S. 499-512 
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The B-to-A conformational transition of calf thymus DNA fibers was followed employing Raman spectroscopy. The transition was induced by soaking DNA fibers in water/ethanol mixtures increasing from 60 to 85% ethanol (v/v). Intensity changes of 17 Raman vibrational bands were quantified in the region from 400 to 860 cm-1. Two bands at 500 and 784 cm-1 were employed as internal standards. These bands do not appear to change in intensity with ethanol concentration. Large intensity changes relative to these two bands are observed between 70 and 74% ethanol for backbone vibrations at 708, 808, and 835 cm-1, and base vibrations at 682, 730, and 750 cm-1. These results indicate that a highly cooperative conformational change takes place between different portions of DNA in the B-to-A transition. Relative intensity changes preceding the onset of the major transition are observed in only two bands; at 835 cm-1, assigned to a ribose-phosphate vibration, and at 750 cm-1, assigned to thymine. The implications of these pretransition changes are discussed.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 24 (1984), S. 328-344 
    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: A quantitative model which described the microscopic and macroscopic refractive index properties of uniaxially oriented crystalline polymers has been extended in relation to molecular bond polarizabilities in this work. Application of this extended modeling methodology in analyzing measured refractive index data for a series of unoriented and oriented samples of linear polyethylene provided Δco = 0.0585 and Δao = 0.194 as the most probable crystalline and noncrystalline intrinsic birefringences for samples exhibiting spherulitic morphology. With these intrinsic birefringences, noncrystalline orientation functions were determined from the optical measurements coupled to the model and the results compared to values obtained from infrared measurements. This comparison of noncrystalline orientation functions, as well as from low density polyethylene reported by other investigators, provided experimental justification for our modeling methodology to examine the possibility of changing intrinsic birefringences for polyethylene as a function of orientation and morphology. The results of this examination demonstrated that values for Δco = 0.0585 and Δao = 0.12 should be used for both low and high density polyethylene samples oriented above the spherulitic to fibrillar transition region.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    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: The monomer 2-butenyl acrylate was reacted with starch by exposure to either 60Co irradiation or ceric ion initiation. Monomer conversion in the presence of starch is greater than in the absence of starch, indicating that a starch initiating mechanism takes place for 60Co irradiated samples. Acetone extraction indicates little or no soluble homopolymer in the grafts. Portions of the samples soluble in dimethyl sulfoxide (DMSO) appear to be low-level 2-butenyl acrylate-grafted starch by infrared analysis. DMSO-insoluble portions (usually more than 50% of each sample) are somewhat more soluble in 1N NaOH at room temperature. This indicates that the 2-butenyl acrylate acts as an easily hydrolyzed crosslink for starch in samples containing as low as 5 wt % grafted poly(2-butenyl acrylate).
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...