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
    Electron microscopy, neutron diffraction, and physical properties of bismuth strontium copper oxide (Bi4Sr8Cu5O19+y) (1991)
    s.l. : American Chemical Society
    Chemistry of materials 3 (1991), S. 844-852 
    Details
    ISSN: 1520-5002
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/cm00017a020
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Ingestion rate, assimilation efficiency and energy balance in Mytilus chilensis in relation to body size and different algal concentrations (1982)
    Springer
    Marine biology 67 (1982), S. 255-266 
    Details
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Basing on a quantification of filtration, ingestion, assimilation, biodeposition, excretion and respiration rate, energy budgets were established in Mytilus chilensis Hupé in relation to body size and three different food concentrations of the unicellular green alga Dunaliella marina. The present quantifications revealed that in M. chilensis the ingestion rate only increases slightly with an increase in food concentration which, however, is counterbalanced by a significant decrease in assimilation efficiency in such a way that assimilation rate finally is nearly constant and independent of the food concentrations tested. The quantifications of these results are given by the a-values of the general allometric growth equation P=aWb relating the energy disposable for growth and reproduction (P; cal d-1 to body size (W; dry-tissue wt, g). The best energy budget was obtained at the lowest food concentration tested (0.8 mg algal dry wt l-1; at 12°C and 30‰ S) with an a-value of 58.8, while the energy budget at the highest food concentration (2.14 mg l-1) was only slightly lower with an a-value of 49.8; the b-values were 0.49 and 0.51, respectively. The net growth efficiencies (K2) decreased with increasing body size (from 20 mg to 3 000 mg drytissue wt) from 76.7 to 47.9% at the lowest food level and from 72.6 to 44.0% at the highest food level tested. These relatively high net growth efficiencies seem to reflect optimal experimental conditions. Furthermore, by a comparison of estimated growth (calculated on the basis of the best energy budget) with growth actually quantified in culture raft mussels in the south of Chile during the highest production period of the year, it is obvious that the energy budgets established really reflect the conditions experienced by the mussels in their natural environment.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00397666
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Phase separation in materials of the systems TiO2-SiO2 and ZrO2-SiO2 prepared by the alkoxide route (1990)
    Springer
    Journal of materials science 9 (1990), S. 173-176 
    Details
    ISSN: 1573-4811
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00727707
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Influence of temperature and time on the stability of silver in silica sol-gel glasses (1997)
    Springer
    Journal of sol gel science and technology 8 (1997), S. 917-921 
    Details
    ISSN: 1573-4846
    Keywords: silver doped glasses ; silver stability ; colloidal silver ; thermochromic glasses
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The darkening of silica sol-gel glasses doped with 0.05 mol% silver was studied. Six sols were prepared from TEOS and silver nitrate. Different additives were used, to influence the chemical and physical states of silver: oxidizing or reducing agents (H2O2, As2O5), colloid stabilizer (sodium citrate) and network modifiers (Li2O, CaO). Sols were gelified at 60°C and densified at 600°C. The samples without additives and those prepared with H2O2 at room temperature even if they were protected from light. With increased temperature, the darkening became samples were heated above, 400°C, reversible bleaching took place. This darkening-bleaching is of thermal nature (“thermochromic effect”) and seems to be determined by a reversible aggregation-disaggregation of tiny silver particles. The presence of sodium citrate, as an additive delayed the darkening effect and the presence of CaO delayed it even further. Lithium oxide inhibited it totally.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02436960
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Microhardness and toughness of Na2O-B2O3-SiO2 materials prepared by the sol-gel procedure (1988)
    Springer
    Journal of materials science 7 (1988), S. 791-792 
    Details
    ISSN: 1573-4811
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00722103
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Preparation and characterization of silicate gel glasses containing Cr2O3 (1994)
    Springer
    Journal of sol gel science and technology 2 (1994), S. 895-901 
    Details
    ISSN: 1573-4846
    Keywords: color ; silica glass ; sol-gel
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The effect of thermal treatment on the structural incorporation of Cr2O3 in xCr2O3·(100 − x)SiO2 and 5R n O·xCr2O3·(95 − x)SiO2 (where x=0.01−1 mol.% and R=Li, Na and Ca) gel glasses was studied by optical absorption spectrophotometry, DTA-TG, XRD and electron microscopy. Samples heat treated at 60°C have green color due to the presence of Cr3+ in octahedral coordination. The optical transmission, and color (yellow, orange or ambar), of the samples heat treated between 200 and 700°C prove that Cr3+ (octahedrally coordinated) and Cr6+ (tetrahedrally coordinated) are both present. Segregation of Cr2O3 take place at temperatures above 800°C. In reducing conditions the gel glasses were green due to the presence of a high content of Cr3+ ions. Samples containing Li or Na show crystalline phases at temperatures below 850°C.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00486372
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Coloration mechanism in silicate gels and gel-glasses containing iron (1996)
    Springer
    Journal of sol gel science and technology 6 (1996), S. 169-177 
    Details
    ISSN: 1573-4846
    Keywords: iron oxide ; colloidal particles ; color mechanism ; spectrophotometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The present investigation was carried out in order to study the incorporation of iron oxide in several samples with a general composition xFeO-(100-x)SiO2 (x between 0.1 and 9.5) and 5RnO-xFeO-(95-x)SiO2 (R=Li, Na or Ca) prepared by the sol-gel method. Samples were gelated and dried at 60°C and thermally treated between 200 and 1000°C in oxidizing and reducing atmospheres. The color change and structural evolution were studied by VIS and NIR spectrophotometry, TEM and X-ray diffraction. When the temperature increases, the color changes from yellow to brown-reddishness, going through a bright ruby-red, at the same time the absorption edge shifts to higher wavelengths and at elevated temperatures to smaller wavelengths newly. A part of iron oxide is incorporated into the glass network and the remaining as colloidal particles, producing a double mechanism of coloration by optical absorption and dispersion. In the samples heat-treated in oxidizing conditions all iron is present in the ferric state. When the heat-treatment is carried out in reducing conditions the presence of iron (II) was detected at temperatures of nearly 1000°C.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00425974
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Fermentation ofd-xylose,d-glucose andl-arabinose mixture byPichia stipitis Y 7124: sugar tolerance (1988)
    Springer
    Applied microbiology and biotechnology 29 (1988), S. 155-161 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Summary The effect of substrate concentration (S 0) on the fermentation parameters of a sugar mixture byPichia stipitis Y 7124 was investigated under anaerobic and microaerobic conditions. Under microaerobiosisP. stipitis maintained high ethanol yield and productivity when initial substrate concentration did not exceed 150 g/l; ethanol yield of about 0.40 g/g and volumetric productivity up to 0.39 g/l per hour were obtained. Optimal specific ethanol productivity (0.2 g/g per hour) was observed withS 0=110 g/l. Under anaerobic conditionsP. stipitis exhibited the highest fermentative performances atS 0=20 g/l; it produced ethanol with a yield of 0.42 g/g, with a specific rate of 1.1 g/g per day. When the initial substrate level increased, specific ethanol productivity declined gradually and ethanol yield was dependent on the degree of utilization of each sugar in the mixture.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01982895
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Fermentation ofd-xylose,d-glucose andl-arabinose mixture byPichia stipitis Y 7124: sugar tolerance (1988)
    Springer
    Applied microbiology and biotechnology 29 (1988), S. 155-161 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Summary The effect of substrate concentration (S 0) on the fermentation parameters of a sugar mixture byPichia stipitis Y 7124 was investigated under anaerobic and microaerobic conditions. Under microaerobiosisP. stipitis maintained high ethanol yield and productivity when initial substrate concentration did not exceed 150 g/l; ethanol yield of about 0.40 g/g and volumetric productivity up to 0.39 g/l per hour were obtained. Optimal specific ethanol productivity (0.2 g/g per hour) was observed withS 0=110 g/l. Under anaerobic conditionsP. stipitis exhibited the highest fermentative performances atS 0=20 g/l; it produced ethanol with a yield of 0.42 g/g, with a specific rate of 1.1 g/g per day. When the initial substrate level increased, specific ethanol productivity declined gradually and ethanol yield was dependent on the degree of utilization of each sugar in the mixture.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00939300
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Comparative study of ethanol production by an immobilized yeast in a tubular reactor and in a multistage reactor (1982)
    Springer
    Applied microbiology and biotechnology 15 (1982), S. 1-8 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Summary The productivity of continuous ethanol fermentation has been increased using fixed bed reactors where a high density of yeast cells was maintained on a packing of wood chips. Two different systems have been used: 1. A tubular reactor which produced alcohol solutions containing up to 13.5% (V/V) ethanol. High CO2 retention and a poor mass transfer between bulk medium and immobilized biomass prevented production rates higher than 2.2 g/l·h. 2. A multistage reactor where a better utilisation of the reactor volume led to improved performances. Solutions containing 132 g/l of ethanol (16.5% V/V) were produced with a productivity increased up to 4.8 g/l·h. A better distribution of the active biomass and a lower gradient of alcohol concentration between support and bulk medium are possible reasons for this improvement.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01875392
    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...