ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

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
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-202-101
    In: Research report / Cold Regions Research and Engineering Laboratory, 101
    Description / Table of Contents: Partial Summary: This paper is a pilot study of interrelations between structural features readily observed in horizontal thin sections of sea ice under low magnification. The core studied was 31.4 cm in length and was collected from Elson Lagoon at Point Barrow, Alaska on 26 October 1960.
    Type of Medium: Series available for loan
    Pages: iv, 11 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory 101
    Language: English
    Note: CONTENTS Preface Summary Introduction Petrographic characteristics Intercrystalline features Intracrystalline features References
    Location: AWI Reading room
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-202-117
    In: Research report / Cold Regions Research and Engineering Laboratory, 117
    Description / Table of Contents: Summary: An experiment was designed to investigate operator-variance in the determination of the plastic limit of cohesive soils, independent of sample preparation and hydration time. A standard sample was prepared by dry-mixing commercial clay, "Grundite", with a pure silt. After the sample was hydrated for 3 weeks, five random samples were taken and five replicates performed on each sample. Analysis of variance (AOV) shows that there is no reason to doubt that the sample is homogeneous at the 0.05 level of significance. Random samples were then distributed to five zones of operators, where a zone is defined as a group of operators with similar backgrounds and engineering interests. Two operators from each group performed five replicates. The AOV model used in the analysis is mixed with the upper level fixed and the two lower levels random. The estimated "within" and "between" operator variances are 0. 45 and 4. 18 respectively. The estimated "between zones" contribution to the total sum of squares is negative. No correlation was found between an operator's internal variance and his deviation from the grand mean. On the basis of this experiment, no reason-exists to doubt that an "untrained" operator can obtain results comparable to those of professional operators. The major factor contributing to the total sample variance is the inconsistency between the individual operators who, although able to duplicate their own determinations, do not call the same end point. To minimize between operator variance, a readily prepared standard sample is suggested with which any operator can calibrate his plastic limit determinations against the expected national average.
    Type of Medium: Series available for loan
    Pages: iv, 8 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory 117
    Language: English
    Note: CONTENTS Preface Summary ­Introduction Sample preparation Sample homogeneity Distribution of samples Analysis Conclusions and suggested standardization References
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Series available for loan
    Series available for loan
    Hanover, NH : U.S. Army Cold Regions Research and Engineering Laboratory
    Associated volumes
    Call number: ZSP-202-80
    In: Research report / Cold Regions Research and Engineering Laboratory, 80
    Description / Table of Contents: From the Introduction: During the last few years, there has been an increased interest in developing a rational explanation for the rather considerable variation in such bulk properties of sea ice as its strength, density, thermal conductivity, latent heat of melting, and coefficient of thermal expansion. Of these properties, sea-ice strength has received by far the most attention for practical reasons.
    Type of Medium: Series available for loan
    Pages: iv, 30, A6, B10, C2, D5 Seiten , Illustrationen
    Series Statement: Research report / Cold Regions Research and Engineering Laboratory 80
    Language: English
    Note: CONTENTS Preface Summary Introduction Experimentation Method of growing salt ice Strength test procedures Bulk properties of salt ice Phase relations Density and air content Strength results Strength of fresh-water ice Strength of NaCl ice as a function of brine volume Strength of NaCl· 2H2O ice as a function of the relative volume of solid salt Effect of thermal history on salt-ice strength Phase hysteresis Geometric hysteresis Effect of short-term cooling on the strength of fresh-water and NaCl·2H2O ice Effect of the volume of inclosed air on the strength of salt ice Conclusions NaCl ice Sea ice References Appendix A: Volume of brine and NaCl· 2H2O in NaCl ice as a function of salinity and temperature Appendix B: Ring test results Normal test sequences Appendix C: Ring test results Hysteresis test sequences Appendix .b: Ring test results Thermal history test sequences
    Location: AWI Archive
    Branch Library: AWI Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 1960-11-01
    Print ISSN: 0022-1376
    Electronic ISSN: 1537-5269
    Topics: Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 1962-01-01
    Description: To resolve some of the factors causing strength variation in natural sea ice, fresh water and five different NaCl–H2O solutions were frozen in a tank designed to simulate the one-dimensional cooling of natural bodies of water. The resulting ice was structurally similar to lake and sea ice. The salinity of the salt ice varied from 1‰ to 22‰. Tables of brine volumes and densities were computed for these salinities in the temperature range 0° to −35° C. The ring-tensile strength σ of fresh-water ice was found to be essentially temperature independent from −10° to −30°C., with an average value of 29.6±8.5 kg./cm.2at −10° C. The strength of salt ice at temperatures above the eutectic point (–21.2° C.) significantly decreases with brine volumev;. The σ–axis intercept of this line is comparable to the a values determined for fresh ice indicating that there is little, if any, difference in stress concentration between sea and lake ice as a result of the presence of brine pockets. The strength of ice containing NaCl.2H2O is slightly less than the strength of freshwater ice and is independent of the volume of solid salt and the ice temperature. No evidence was found for the existence of either phase or geometric hysteresis in NaCl ice. The strength of ice at sub-eutectic temperatures, however, is decreased appreciably if the ice has been subjected to temperatures above the eutectic point; this is the result of the redistribution of brine during the warm-temperature period. Short-term cooling produces an appreciable (20 per cent) decrease in strength, in fresh-water and NaCl.2H2O ice. The present results are compared with tests on natural sea ice and it is suggested that the strength of freshwater ice is a limit which is approached but not exceeded by cold sea ice and that the reinforcement of brine pockets by Na2SO4.10H2O is either lacking or much less than previously assumed.
    Print ISSN: 0022-1430
    Electronic ISSN: 1727-5652
    Topics: Geography , Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 1962-01-01
    Description: To resolve some of the factors causing strength variation in natural sea ice, fresh water and five different NaCl–H2O solutions were frozen in a tank designed to simulate the one-dimensional cooling of natural bodies of water. The resulting ice was structurally similar to lake and sea ice. The salinity of the salt ice varied from 1‰ to 22‰. Tables of brine volumes and densities were computed for these salinities in the temperature range 0° to −35° C. The ring-tensile strength σ of fresh-water ice was found to be essentially temperature independent from −10° to −30°C., with an average value of 29.6±8.5 kg./cm.2 at −10° C. The strength of salt ice at temperatures above the eutectic point (–21.2° C.) significantly decreases with brine volume v;. The σ–axis intercept of this line is comparable to the a values determined for fresh ice indicating that there is little, if any, difference in stress concentration between sea and lake ice as a result of the presence of brine pockets. The strength of ice containing NaCl.2H2O is slightly less than the strength of freshwater ice and is independent of the volume of solid salt and the ice temperature. No evidence was found for the existence of either phase or geometric hysteresis in NaCl ice. The strength of ice at sub-eutectic temperatures, however, is decreased appreciably if the ice has been subjected to temperatures above the eutectic point; this is the result of the redistribution of brine during the warm-temperature period. Short-term cooling produces an appreciable (20 per cent) decrease in strength, in fresh-water and NaCl.2H2O ice. The present results are compared with tests on natural sea ice and it is suggested that the strength of freshwater ice is a limit which is approached but not exceeded by cold sea ice and that the reinforcement of brine pockets by Na2SO4.10H2O is either lacking or much less than previously assumed.
    Print ISSN: 0022-1430
    Electronic ISSN: 1727-5652
    Topics: Geography , Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...