Library

X
You have 0 saved results.
Mark results and click the "Add To Watchlist" link in order to add them to this list.
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
    Role of Surface Effects in the Inelastic Background of X-ray Photoelectron Spectroscopy (1996)
    Chichester [u.a.] : Wiley-Blackwell
    Surface and Interface Analysis 24 (1996), S. 490-496 
    Details
    ISSN: 0142-2421
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Physics
    Notes: We have derived a new deconvolution formula to obtain the original no-loss XPS spectra, the so-called source function, by taking surface effects into account. With this formula the primary XPS spectra of Au 4d and Au 4f are carried out from the experimental data. The primary excitation spectra are compared to the results derived by Tougaard’s method in which surface effects were neglected. The present result is markedly different from Tougaard’s result, which consists of a tail extending ∽50 eV below the peak. The result reveals that the influence of surface effects on the background removal of the spectra is considerably significant for the energy range ∽50 eV below the peak energy. It is also found that the large tail in Tougaard’s results can be essentially removed when surface effects are considered.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
  • 2
    Electronic Resource
    Electronic Resource
    Characterization of azo-containing polydimethylsiloxanes and their copolymers with methyl methacrylate (1996)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 2613-2620 
    Details
    ISSN: 0887-624X
    Keywords: polydimethylsiloxane ; poly(methyl methacrylate) ; block copolymer ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Azo group-containing polydimethylsiloxanes (PDMS-ACP), macroazoinitiators, were prepared by polycondensation reaction of 4,4′-azobis-4-cyanopentanoyl chloride (ACPC) with hydroxybutyl-terminated polydimethylsiloxane (PDMS) of varying molecular weights. The activation energy (Ea), activation enthalpy (ΔH
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
  • 3
    Electronic Resource
    Electronic Resource
    Siderophore-Mediated microbial iron(III) uptake: An exercise in chiral recognition (1993)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 5 (1993), S. 359-365 
    Details
    ISSN: 0899-0042
    Keywords: synthetic siderophore analogs ; hydroxamates ; ferrichrome ; ferrioxamine ; coprogen ; Pseudomonas putida ; membrane receptors ; transport proteins ; growth promotion ; growth inhibition ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Molecular recognition by microbial receptors for siderophores [natural iron(III) carriers] is examined with synthetic iron(III) carriers as structural probes. The iron(III) carriers have been designed to reproduce the two essential features of the natural siderophores: the capability to form octahedral iron(III) binding cavities and to fit specific membrane receptors. Specifically, analogs of tripodal ferrichrome and linear ferrioxamines have been prepared and examined. The ferrichrome analogs rely on C3-symmetric binders that are assembled from triscarboxylates as anchors, amino acids as bridges, and terminal hydroxamate groups as binding sites. The ferrioxamine analogs are based on linear assemblies of three identical monomers, each derived from a chiral amino acid. The deliberate use of animo acid residues as variable building blocks enables us to systematically modify the molecules' envelopes and the preferred absolute configuration of the iron(III) complexes until optimal performance is reached. Examination of the synthetic analogs in Pseudomonas putida demonstrates that the domains around the iron(III) center and their chiral sense dictate the extent of recognition by the membrane receptors. It is also shown that the synthetic siderophore analogs may be designed to either exert a broader, or a more narrow range of microbial activity than the natural siderophores. The implications of these findings are discussed in relation to the possible design of species-specific antimicrobial agents. © 1993 Wiley-Liss, Inc.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/chir.530050516
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Role of surfactant in composite latex particle morphology (1992)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 45 (1992), S. 487-499 
    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: Composite particles were prepared by seeded emulsion polymerization at 70°C using K2S2O8 as initiator and two different nonionic surfactants. Monodisperse polystyrene latex particles were used as seed and methyl methacrylate was used as second-stage monomer. When the surfactant, polyethylene oxide-propylene oxide (Pluronic F-108), was used, the final particle morphology showed that the PMMA (core) was partially covered by polystyrene. However, when nonyphenol polyethylene oxide (Igepal Co-990) was used as surfactant, one observed a reversed type of encapsulation (i.e., PS core is partially engulfed by PMMA). The interfacial tensions of the polymer phase against water containing the appropriate surfactant were measured by the drop-volume method and used in a mathematical model based on thermodynamic analysis to predict the equilibrium particle morphology. The observed particle morphologies were found to differ from the predicted morphologies at low conversion of the second-stage monomer but agreed with it at higher conversion.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1992.070450313
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Characterization of carboxylated poly(butyl acrylate) latices produced by a semibatch process (1996)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 62 (1996), S. 585-594 
    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: Several carboxylated poly(butyl acrylate) latices prepared by a semibatch emulsion poly-merization process were characterized in this study. A significant amount of polyelectrolyte was found in the latex product containing 10% AA, designated as AA10. On the other hand, latices containing 0.1% AA (AA0.1), 0.1% MAA (MAAC.1), and 10% MAA (MAA10) showed very low levels of polyelectrolyte in water. Based on the critical flocculation concentration data, it can be concluded that incorporation of 10% AA or 10% MAA into the emulsion polymers can greatly improve the chemical stability of the latex products, especially at higher pH. The data of the pH and conductometric titration experiments show that the MAA unit can be distributed more uniformly in the latex particles in comparision with the AA unit. This result is further confirmed by determination of the Tg's of the emulsion polymers by means of thermally stimulated current (TSC). © 1996 John Wiley & Sons, Inc.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
  • 6
    Electronic Resource
    Electronic Resource
    The effect of hexane treatment on the permeation of silicone-coated polyethersulfone membranesIssued as NRCC No. 31483. (1990)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 41 (1990), S. 2169-2176 
    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: The polyethersulfone membranes were cast from casting solutions including poly(vinyl pyrrolidone) additive. The membranes were further dried, silicone-coated, and used for the permeation study with hydrogen and nitrogen gases. It has been found that solvent hexane which was included in the silicone rubber solution for surface coating increased the pore size on the membranes surface when poly(vinyl pyrrolidone) was present in the membrane. The above effect counteracted the pore size decrease by silicone coating, and, as a result, an H2/N2 permeability ratio of only 8.9 was achieved as compared with 28, which was obtained when the base polyethersulfone membrane was prepared from a casting solution without poly(vinyl pyrrolidone) additive.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1990.070410921
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    The influence of molecular weight on the large deformation behavior of SBS triblock copolymer elastomers (1977)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 21 (1977), S. 629-643 
    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: Engineering stress-strain properties were determined for two polystyrene-polybutadiene-polystyrene (SBS) triblock copolymer elastomers, one consisting of blocks of molecular weight 7000/43000/7000 and the other, 16000/85000/17000. In addition, various blends of these two materials were prepared in order to vary the number-average molecular weight of the blocks in a systematic way while maintaining polystyrene content in the range of 25-28 wt %. Samples were solvent cast from benzene or benzene/heptane mixtures and annealed before testing. Ring specimens were extended to rupture at varying strain rates on an Instron tensile tester. Results indicate that number-average molecular weight has a marked influence on stress-strain behavior over the range of molecular weights and testing conditions employed. The observed behavior is consistent with a systematic increase in the proportion of a mixed interfacial region between the pure polystyrene and polybutadiene domain as molecular weight decreases. The interfacial region contributes to mechanical hystersis, rate sensitivity, and toughness in the SBS materials. Scanning electron photomicrographs of fracture surfaces also showed systematic changes with molecular weight.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1977.070210305
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Nylon 4/PVA blend membrane for dialysis (1991)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 43 (1991), S. 1795-1804 
    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: To improve the hydrophilicity and enhance the transport flux of nylon 4 membrane for dialysis, this study attempts to utilize blending nylon 4 with poly(vinyl alcohol) (PVA). The instability of PVA in water can be obtained more easily than by other methods, such as chemical, γ-ray irradiated crosslinking, or high-temperature treatment used by previous researchers. The effects of maturation time of the casting solution, nylon 4/PVA ratios, and casting solvent compositions on esterification of PVA, salt permeability, water content, partition coefficient, diffusivity, and mechanical strength of membrances are studied. The membrane, prepared by casting solution of nylon 4/PVA = 9/1 wt % formic acid with 24-h maturation time, possesses permeabilities of NaCl and urea, 33.14 and 19.67 × 10-5 cm2/min, respectively.
    Additional Material: 14 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1991.070431003
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Concentration dependence of surface diffusion and zeolitic diffusion (1991)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 37 (1991), S. 1579-1582 
    Details
    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
    URL: http://dx.doi.org/10.1002/aic.690371015
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Diffusion of oxygen, nitrogen and their mixtures in carbon molecular sieve (1994)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 40 (1994), S. 577-585 
    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: Diffusivities of oxygen, nitrogen and their mixtures in carbon molecular sieve are measured under conditions used for kinetic separation of air by adsorption (elevated pressures). In binary diffusion, codiffusion enhances fluxes for both components, whereas counterdiffusion has the opposite effects; for both cases, the effects are significantly more pronounced for the fast diffusing component. The multicomponent diffusion theory developed earlier in this laboratory for surface diffusion is reformulated for diffusion in molecular sieves. Multicomponent diffusivities can be predicted from the following pure-component information: concentration-dependent diffusivities and diffusional activation energies. Predicted binary diffusion results agree fairly with the experimental data for oxygen and nitrogen in carbon molecular sieve.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690400402
    Library Location Call Number Volume/Issue/Year 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...