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
  • 1
    Electronic Resource
    Electronic Resource
    Effects of mat moisture content and press closing speed on the formation of density profile and properties of particleboard (1998)
    Springer
    Journal of wood science 44 (1998), S. 287-295 
    Details
    ISSN: 1611-4663
    Keywords: Particleboard ; Mat moisture content ; Press closing speed ; Density profile ; Board properties
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Isocyanate resin-bonded 0.5 and 0.7 g/cm3 lauan (Shorea sp.) particleboards were produced from mats with uniform and distributed moisture content (MC) distributions, using three hot press closing speeds. The effects of these processing variables on the formation of density profile in particleboard and board properties were analyzed statistically. A definition of the density profile was introduced, and the correlations among the various defining factors were established. The results are summarized as follows. (1) The peak density (PD) of particleboard could be increased, with a slight reduction in the core density (CD), using mats with different MC distributions. (2) In a conventional density profile, CD and PD are highly dependent on the board mean density (MD); and the gradient factor (GF), peak distance from the faces (Pdi), and peak base (Pb) are significantly correlated to each other, at the 99% significance level. (3) Greater press closing speed reduces Pdi and Pb, with an increase in GF. (4) Greater press closing speed could increase the PD in board of low MD, with minimal effect on CD. (5) The modulus of elasticity (MOE) of particleboards from mats with high MC near the faces were consistently higher than those from mats with uniform MC, irrespective of the press closing speed, whereas their modulus of rupture (MOR) became indifferent at higher MD under slow and fast closing speeds. (6) Sanding does not improve the MOR and MOE of particleboard significantly.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00581309
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Formation of the density profile and its effects on the properties of fiberboard (2000)
    Springer
    Journal of wood science 46 (2000), S. 202-209 
    Details
    ISSN: 1611-4663
    Keywords: Fiberboard ; Density profile ; Hot pressing method ; Mat moisture content
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Two main types of fiberboards were produced using lauan (Shorea spp.) fibers with an isocyanate resin as the binder; fiberboard with a flat, homogeneous (homoprofile), and typical U-shaped (conventional) density profile along the board thickness. The processing parameters included manipulation of mat moisture content distribution, press closing speed, and hot pressing method. The results are summarized as follows: (1) A larger variation was observed in the peak density (PD) and core density (CD) of fiberboards at 0.5g/cm3 mean density (MD) level than in those at 0.7 g/cm3. Generally, PD showed a greater variation than CD, irrespective of MD level. (2) Boards produced using two-step hot pressing recorded substantially higher PD with reduced CD. (3) Multiple regression analysis showed that CD and PD could be calculated based on the other profile defining factors, and a rough estimation for peak distance and gradient factor was possible. (4) Based on static bending, conventional fiberboard had a higher modulus of rupture (MOR) than the homo-profile board but a similar modulus of elasticity (MOE). (5) At 0.5 g/cm3 the MOR and dynamic MOE of fiberboard increased by up to 67% and 62%, respectively, when the PD increased from 0.5 to 1.07 g/cm3. Similarly, an increase of PD from 0.7 to 1.1 g/cm3 resulted in corresponding increases of 55% and 34% in the MOR and dynamic MOE of 0.7 g/cm3 boards. (6) The internal bond strength and screw withdrawal resistance were almost entirely dependent on the CD and MD, respectively. (7) Homo-profile fiberboards registered higher thickness swelling and water absorption than conventional fiberboards throughout the dry/wet conditioning cycle.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00776450
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Solution conformation study of substance P methyl ester and [Nle10]-neurokinin A (4-10) by nmr spectroscopy (1993)
    New York : Wiley-Blackwell
    Biopolymers 33 (1993), S. 1901-1908 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: High-resolution proton spectra at 500 MHz of two tachykinin peptides, substance P methyl ester (SPOMe) and [Nle10]-neurokinin A (4-10), have been obtained in dimethylsulfoxide (DMSO), and for SPOMe, also in 2, 2, 2-trifluoroethanol (TFE)/water mixtures. Complete chemical shift assignments for these peptides were made based on two-dimensional (2D) nmr techniques, correlated spectroscopy and total COSY. J coupling measurement and nuclear Overhauser effect spectroscopy (NOESY) were then used to determine the conformation of these peptides in the various solvents. Based on the J coupling, NOE correlations, and temperature coefficients of the NH resonances, it is concluded that these two peptides exist in DMSO at room temperature as a mixture of conformers that are primarily extended. For SPOMe in TFE/water with high TFE content, however, helical structures are found to be present, and they become quite clear at temperatures between 270 and 280 K. The variation of the 13C chemical shifts of the Cα (the secondary shift) with TFE contents corroborates this conclusion. The NOE and Cα shifts show that the main helical region for SPOMe lies between 4P and 9G. The C-terminus segment L—M—NH2 is found to be quite flexible, which appears to be quite common for neurokinin-1 selective peptides. © 1993 John Wiley & Sons, Inc.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.360331215
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Solution conformation of a cyclic neurokinin antagonist: A nmr and molecular dynamics study (1994)
    New York : Wiley-Blackwell
    Biopolymers 34 (1994), S. 1165-1173 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The solution structure of a hexapeptide, cyclo(Gln-Trp-Phe-Gly-Leu-Met), which is a selective NK-2 antagonist, has been studied by a combination of two-dimensional nmr and molecular dynamics (MD) techniques. The simulation based on nmr and MD data resulted in the convergence to a family of structures. Free molecular dynamics for 50 ps in the presence of DMSO solvent molecules shows that the structure is energetically stable. One intramolecular hydrogen bond between the amide proton of Gin and the carbonyl oxygen of Gly was revealed. This result is consistent with the results from the measurement of the temperature coefficient of the amide protons. The extent of intermolecular hydrogen bonding between the amide protons of the peptide and DMSO was also revealed by the free MD simulation. The resulting structure of the cyclic peptide contains a variation type I′ β-turn in the Gly-Leu-Met-Gln segment. Comparison of the structure of this peptide with that of other NK-2 antagonist cyclic hexapeptides was made, and the activity of cyclic antagonists appears to be inversely related to the conformational rigidity of the cyclic peptides. © 1994 John Wiley & Sons, Inc.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.360340906
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    The infinite velocity method: A new method for SIMS quantification (1994)
    Chichester [u.a.] : Wiley-Blackwell
    Surface and Interface Analysis 21 (1994), S. 747-757 
    Details
    ISSN: 0142-2421
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: Twelve elements spanning a mass range of 197 atomic mass units from five standard reference materials and three implant materials were analysed to ascertain the validity of a new method, termed the infinite velocity method, for quantifying the negative monatomic secondary ion emissions resulting from Cs-bombarded surfaces. This method extracts quantitative data by extrapolating secondary ion yield versus kinetic energy data to the infinite velocity limit. Extrapolation to infinite velocity is done because matrix effects are theoretically predicted to be removed at this limit. Plotting the extrapolated data against known concentrations for the homogeneous standard reference materials yielded linear standardization curves for all elements analysed, indicating that the matrix effect is indeed removed, i.e. sensitivity factors were not required. Likewise, the resulting concentration profiles of the implant materials analysed agreed well with concentration profiles calculated via the integration method. Thus, samples can be quantified by this procedure without the requirement for matrix-matched calibration materials. Theoretical implications and the assumptions used in the calculations are also discussed.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/sia.740211103
    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...