ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
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
  • Engineering  (3,321)
  • Chemical Engineering  (3,294)
  • 1990-1994  (6,615)
  • 1
    facet.materialart.
    Unknown
    M.D.-Ph.D. degrees (1993)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 1993-12-17
    Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Gottheil, D L -- Waldrop, T G -- New York, N.Y. -- Science. 1993 Dec 17;262(5141):1801-2.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/8266063" target="_blank"〉PubMed〈/a〉
    Keywords: *Education, Graduate ; *Education, Medical ; Engineering ; Humanities ; Humans ; Research ; Science ; Social Sciences
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 2
    Electronic Resource
    Electronic Resource
    Introducing engineering into American secondary education (1993)
    Springer
    Journal of science education and technology 2 (1993), S. 397-406 
    Details
    ISSN: 1573-1839
    Keywords: Engineering ; technological literacy ; hands-on experiments ; active learning ; content instruction ; videotaping
    Source: Springer Online Journal Archives 1860-2000
    Topics: Natural Sciences in General , Technology
    Notes: Abstract Media reports indicate the decline of the technological literacy of American youth, especially that students in other countries are better prepared in science and mathematics. Our active-learning program, which consists of numerous hands-on experiments, introduces engineering applications into science and math programs, that will demonstrate to students the usefulness of the theory that they currently do not see as useful. The program, when fully developed, will make optimum use of technology, especially computers and videotapes. The hands-on experiments allow students to discover fundamental principles through data analysis and then use the principles to synthesize a solution to a technological problem. This discovery-based education will help school systems better meet performance standards such as those in the Maryland School Performance Plan. The experimental approach to science education is especially important in a technology-oriented economy where children use the new technologies without understanding the principles on which they are based.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00694528
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Polymer blend containing a thermotropic polyester with long flexible spacer in the main chain (1990)
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 30 (1990), S. 22-29 
    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: Polymer blends of nylon 66 and thermotropic polyester with long flexible spacers in the main chains were prepared by melt mixing. The samples were made as single filaments by passing the polymer blend through a small and round die of a capillary rheometer. Mechanical properties of blends showed that the modulus and strength of nylon 66 could be improved without reduction of extensibility. The morphology of fractured surfaces was observed by a scanning electron microscope (SEM). It showed that the microfibrillar structure of a thermotropic polyester was formed by extensional flow while the spherical and ellipsoidal particles in the nylon 66 (matrix polymer) were produced by shear flow. The polyester particles were occasionally covered with adhering matrix polymer because of good adhesion between these two polymers. They were highly elongated by tensile stress without loss of elongational characteristics of blends. This fact was explained by very good adhesion between the two phases.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pen.760300105
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Gelation in thermosets formed by chain addition polymerization (1990)
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 30 (1990), S. 83-89 
    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: The physical behavior of the diglycidyl ether of bisphenol A, cured with different concentrations of 2-ethyl-4-methylimidazole, was examined with dynamic mechanical and dielectric analyses, differential scanning calorimetry, and solvent extraction studies, ‘The network formation process was shown to depend strongly on the imidazole concentration’. At high imidazole concentrations, the gel point was characterized by a decrease in sol fraction, the crossover of the dynamic moduli and a rapid increase in viscosity. At low imidazole concentrations, the viscosity remained low until the sol fraction approached zero. For this system, the gel point, which occurred prior to the dynamic moduli crossover, was characterized by comparing the thermal properties of the network with the viscosity and dielectric behavior of the resin system during cure.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pen.760300204
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Calculated stresses in dual coated optical fibers (1990)
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 30 (1990), S. 108-117 
    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: We examine several practically important problems, related to the mechanical behavior of dual coated optical fibers: low temperature microbending, evaluation of spring constant due to coating layers, strength of the end portions of fibers clamped in terminal fixtures, and prediction of stresses caused by the misalignment of the openings in the frame and in the terminal fixture. The developed formulas are simple, easy-to-use, and clearly indicate the role of the major factors affecting the mechanical behavior of the fibers. The obtained results can be of help in physical design of dual coated fibers and optical interconnections.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pen.760300207
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Energy absorption characteristics of polymeric foams used as cushioning materials (1990)
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 30 (1990), S. 129-133 
    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: The “Efficiency of Energy Absorption” (or “Efficiency”) and “Ideality” parameters were evaluated for several plastic foams and were found to be very useful in choosing an appropriate cushion for the protection of a specific product. The maxima in these parameters were found to be in the same range of stresses, when derived from dynamic measurements or from predicted stress-strain curves based on previously proposed “Reference” and “Modified Boltzman Superposition” Models. For the rate independent foams the maxima in these parameters do not change with strain rate and can therefore be derived from slow, constant rate (“static”) experiments. For rate dependent foams however, the maxima from “static” measurements were found to be in a lower range of stresses than those derived from dynamic ones. As a result, slow rate compressive measurements do not predict well the behavior of the foams during impact and the use of the “Reference” and “Modified Boltzman Superposition” Models is required for good predictions. It was found that the suffer PS and PE foams attain maximum Efficiency and Ideality at higher stresses than the more flexible PUR foams.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pen.760300210
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Crystallization kinetics of poly(ethylene terephthalate). Part I: Kinetic equation with variable growth rate (1991)
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 31 (1991), S. 110-115 
    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: A new crystallization kinetic equation has been derived considering the decrease in growth rate. The average linear growth rate of spherulite was assumed to be proportional to the m-th order of the uncrystallized fraction of the crystallizing material. A modified Avrami equation, 1 - Vc = exp[-Kf(t)n], was used where f(t) is the integral of the growth function, (1 - Vc)m. The validity of the equation was tested by analyzing the isothermal crystallization kinetic data of poly(ethylene terephthalate) from the melt using differential scanning calorimetry.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pen.760310209
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    The coupled relaxation model for toner melt rheology (1991)
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 31 (1991), S. 99-103 
    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: Process changes aimed at improving printer engine performance must take into consideration not only the process variables (such as nip temperature and pressure and process time to), but also the melt rheological variables (such as the characteristic time scale of the toner Tc). The melt rheology relevant to the electrophotographic toner fusing process is discussed. One criterion for toner quality can be conveniently measured through the Deborah number De, which is the ratio of Tc to to. Modification of the melt rheology by matrix polymer composition and carbon black size and concentration has previously been explored. Here, the melt rheology of toners with a range of gel content was studied using a step shear test. The coupled relaxation model was employed to fit the stress relaxation data. The viscoelastic properties were calculated from the melt data with this model. These properties were then used to estimate the strain deformation of the toner as it passes through the nip with arbitrary residence time and nip pressure as a function of gel content. This method can be used to match the toner melt properties with the processing conditions.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pen.760310207
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Masthead (1991)
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 31 (1991) 
    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
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pen.760310301
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    A unified simulation of the filling and postfilling stages in injection molding. Part II: Experimental verification (1991)
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 31 (1991), S. 125-139 
    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: The unified numerical simulation of the filling/postfilling stages of the injection-molding process described in Part I is compared in the present paper with experimental results obtained with instrumented test molds. Flush-mounted pressure traces in the delivery system as well as in the cavity are favorably compared with corresponding predictions for both an amorphous and a semicrystalline polymer. It is demonstrated that the present unified formulation is well suited to handle complicated molds where compressibility effects can become important even during the filling stage, as portions of the cavity fill and undergo a packing behavior even when other regions of the cavity are still only partially filled.
    Additional Material: 19 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pen.760310211
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...