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  • Wissenschaftspark Albert Einstein  (490)
  • SB Neuruppin
  • TH Brandenburg
  • IGB Berlin
  • Cold Regions Research and Engineering Laboratory 〈Hanover, NH〉  (490)
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  • Wissenschaftspark Albert Einstein  (490)
  • SB Neuruppin
  • TH Brandenburg
  • IGB Berlin
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Schlagwörter
  • 1
    UID:
    kobvindex_GFZ122907
    Umfang: vii, 66 Seiten , Illustrationen
    Serie: Research report / Cold Regions Research and Engineering Laboratory 346
    Inhalt: CONTENTS: Abstract. - Preface. - USA CRREL project and personnel involvement. - Part I. Introduction. - Background. - Literature review. - Part II. CRREL investigations from 1970 - 1974. - Initial literature survey (1970). - Oil detection kit development. - Survey of Cape Simpson, Alaska, natural crude oil seepages (1970). - Haines-Fairbanks military pipeline investigations (1971-1973). - Barrow investigations (1970-1974). - Fairbanks and Fox investigations. - Germination studies. - Physiological studies. - Dispersant studies. - Microbiological investigations. - Field investigations of accidental petroleum losses. - Part III. Recent related literature. - Part IV. Conclusions and recommendations. - USA CRREL reports, publications and presentations on Alaska oil spill research. - Literature cited.
    Inhalt: Knowledge concerning the biological effects of oil pollution on arctic and subarctic terrestrial ecosystems is limited. USA CRREL research personnel conducted investigations from 1970 through 1974 to expand information in this field. Objectives were to: 1) define the ecosystems most sensitive to the presence of crude oil or its refined products, 2) quantify and understand the injury response, and 3) establish time frames for manifestation of damage and natural restorative processes in arctic and subarctic regions. This was accomplished through: 1) surveys of natural oil seepages and past accidential spills in the Arctic and Subarctic, 2) initiation of controlled oil spills and 3) detailed laboratory investigations. Results demonstrated that terrestrial oil spills will to some degree be detrimental to both arctic and subarctic plant communities. Degree and longevity of damage will be influenced primarily by the magnitude of the spill, season of occurrence and existing soil moisture content. Rapid recovery of plant communities subjected to spills will occur only if root systems remain relatively unaffected. Damage will be more extensive and long-term when root systems are saturated with oil. Effects of damage will be manifested gradually over several seasons being influenced by winter stresses. Variation does exist in plant species susceptibility. Carex aquatilis, a predominant sedge of the arctic, is markedly resistant to crude oil damage. In the taiga Picea mariana is very susceptible. Plant recovery can be enhanced through the application of fertilizer. Fertilization, in addition to its direct effect on plant nutrition, will stimulate microbial decomposition of crude oil.
    Anmerkung: MAB0014.001: ZSP-202-346
    In: Research report / Cold Regions Research and Engineering Laboratory, 346
    Sprache: Englisch
    Schlagwort(e): Forschungsbericht
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  • 2
    UID:
    kobvindex_GFZ122903
    Umfang: v, 28 Seiten , Illustrationen
    Serie: Research report / Cold Regions Research and Engineering Laboratory 349
    Inhalt: CONTENTS: Abstract. - Preface. - Introduction. - Test locations. - Post Pond. - Mascoma Lake. - Winter freeze-up. - Ice cover properties. - Stratigraphy. - Microstructure. - Porosity. - Impurity content. - Flexural strength. - Test sites. - Beam test procedure. - Beam dimensions. - Beam temperatures. - Beam strengths. - Results. - Post Pond, Site PB, 12 February 1974. - Post Pond, Site PC, 21 February 1974. - Mascoma Lake, Site MD, 25 February 1974. - Mascoma Lake, Site MD, 26 February 1974. - Mascoma Lake, Site MD, 1 March 1974. - Post Pond, Site PA, 4 March 1974. - Post Pond, Site PA, 7 March 1974. - Post Pond, Site PA, 8 March 1974. - Post Pond, Site PB, 12 March 1974. - Post Pond, Midway between Sites PB and PC, 15 March 1974. - Post Pond, Midway between Sites PA and PB, 26 March 1974. - Post Pond, Midway between Sites PA and PB, 29 March 1974. - Post Pond, Midway between Sites PA and PB, 3 April 1974. - Conclusions. - Literature cited.
    Inhalt: In-place cantilever beam tests on Post Pond and Mascoma Lake ice yielded a maximum flexural strength of 7.1 kg/cm^2. The minimum strength, unrelated to failure along pre-existing cracks in the ice, was 2.9 kg/cm^2. The majority of tests were performed in the push-down mode after it was discovered that beams tested in the pull-up mode, which places the bottom surface in tension, frequently broke prematurely along cracks in the bottom of the ice. Premature failures of this kind usually occurred at stresses of 2-3 kg/cm^2. Data further demonstrate that the intrinsic strength of lake ice decreases significantly as the surface air temperature goes to 0°C. Ice that has just become isothermal, but has not yet begun to candle, has a strength of about 4 kg/cm^2; ice that has been subjected to prolonged periods of above-freezing air temperatures generally fails at about 3 kg/cm^2. Tests also show that cold unrecrystallized snow-ice is as strong as the underlying lake ice. Tests of the effect of crystalline structure indicate that ice composed of crystals with their c-axes horizontal is measurably stronger than ice in which the crystals are oriented with their c-axes vertical.
    Anmerkung: MAB0014.001: ZSP-202-349
    In: Research report / Cold Regions Research and Engineering Laboratory, 349
    Sprache: Englisch
    Schlagwort(e): Forschungsbericht
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  • 3
    UID:
    kobvindex_GFZ20210210102425
    Umfang: v, 20 Seiten , Illustrationen
    Serie: CRREL Report 81-16
    Inhalt: An air-transportable shelter designed and built at CRREL for use in cold regions underwent testing in Hanover, New Hampshire, and Ft. Greely, Alaska. The shelter demonstrated some of its capabilities for mobility by being towed for more than 60 miles behind various vehicles and by being transported on a C-130 cargo airplane, a CH-47 helicopter, and a trailer truck. The shelter proved to be very easy for a crew of two to four to set up in all weather conditions including -40 F cold. However, the gasoline-powered generator, which was a source for space heat as well as electricity, functioned very poorly. Overall, the prototype successfully demonstrated qualities of self-reliance, ease of operation and thermal efficiency.
    Anmerkung: CONTENTS Abstract Preface Metric conversion factors Summary Introduction Description of shelter Test procedures and results Mobility Ease of erecting and striking Therinal efficiency and performance Heat output Electrical system Habitation Safety features Water system Shelter reliability Structure Performance of other shelters Conclusions Future studies Literature cited
    In: CRREL Report, 81-16
    Sprache: Englisch
    Schlagwort(e): Forschungsbericht
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  • 4
    UID:
    kobvindex_GFZ20190703153737
    Umfang: iv, 26 Seiten , Illustrationen
    Serie: CRREL Report 85-17
    Inhalt: This report presents the results of tests of the ice friction coefficient carried out during the May 1984 expedition of the F.S. Polarstern off the coast of Labrador. The test surfaces were Inerta-160-coated steel plates and bare steel plates, hand roughened and sandblasted. The main findings of the studies were: 1) columnar and granularpea ice showed no significant differences in friction coefficient; 2) for columnar ice was independent of ice crystal orientation with respect to test surface; 3) was Independent of normal pressure applied on ice sample; 4) initially decreased with increasing relative velocity between the Ice sample and the test surface and reached a steady value at higher speeds; 5) Uk increased with increasing surface roughness; 6) a wetting surface exhibited a higher friction coefficient than a non-wetting surface of the same or even higher roughness average.
    Anmerkung: CONTENTS Abstract Preface Introduction Test procedure Test apparatus Test surfaces Ice samples Test program Results and discussion Effect of wear of ice sample Effect of normal pressure Effect of velocity, crystal orientation and surface conditions Results summary Comparison with laboratory study Recommendations on test apparatus Literature cited Appendix A : Test results
    In: CRREL Report, 85-17
    Sprache: Englisch
    Schlagwort(e): Forschungsbericht
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  • 5
    UID:
    kobvindex_GFZ20190724150404
    Umfang: v, 30 Seiten , Illustrationen
    Serie: CRREL Report 88-2
    Inhalt: While many materials undergo phase change at a fixed temperature, soil systems exhibit a definite zone of phase change. The variation of unfrozen water with temperature causes a soil system to freeze of thaw over a finite temperature range. Exact and approximate solutions are given for conduction phase change of plane layers of soil with unfrozen water contents that vary linearly and quadratically with temperature. The temperature and phase change depths were found to vary significantly from those predicted for the constant-temperature or Neumann problem. The thermal conductivity and specific heat of the soil within the mushy zone varied as a function of unfrozen water content. It was found that the effect of specific heat is negligible, while the effect of variable thermal conductivity can be accounted for by a proper choice of thermal properties used in the constant-thermal-property solution.
    Anmerkung: CONTENTS Abstract Nomenclature Preface Introduction Basic equations Two-zone problems Linear unfrozen water function Quadratic unfrozen water function Three-zone problems Linear unfrozen water function Quadratic unfrozen water function Conclusions Literature cited Appendix A: Derivation of the mushy zone equation Appendix B: Solution of the two-zone problem with a linear t and variable thermal properties
    In: CRREL Report, 88-2
    Sprache: Englisch
    Schlagwort(e): Forschungsbericht
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  • 6
    UID:
    kobvindex_GFZ20190703154646
    Umfang: iv, 40 Seiten , Illustrationen
    Serie: CRREL Report 85-18
    Inhalt: Concern over the environmental fate of explosives has brought about the development of sensitive analytical methods for measuring them in groundwater. In turn this concern has been extended to validating the sampling procedures for groundwater. This report addresses the potential effects of residual drilling muds on the analysis for explosive contaminants (TNT, DNT, RDX, and HMX) in monitoring wells. The approach was to determine sorption isotherms for each contaminant. Sorption appeared to be independent of solids concentration. Linear isotherms were obtained for RDX and HMX over a range of analytic concentrations; therefore, a single constant can be used to estimate the amount sorbed when the solution concentration is known. Isotherms for TNT and DNT were not linear, however. Scatchard analysis suggested that the isotherms for these analytes could be resolved into two predominant components: a linear component above a certain sorbed quantity and a Langmuir-type component below this quantity. The experimental data were fitted by regression analysis using the appropriate model. The equations developed can be used to predict the sorbed fraction (analytical bias) for any combination of solids and analyte concentration. The amounts of bentonite found in some existing wells do not appear to be sufficient to cause significant bias in analyses for these explosive contaminants.
    Anmerkung: CONTENTS Abstract Preface Introduction Materials and methods Bentonite and water samples Sorbate solutions Sorption isotherms HPLC analysis Analyte standards Water solubilities Octanol-water partition coefficients Sorption isotherms Freundlich Langmuir BET Scatchard Gibbs Linear Polynomial Results and discussion TNT DNT RDX and HMX Effect of drilling muds on analysis SEM and EDXA analysis of bentonite wells Other studies Summary Literature cited Appendix A : Results for TNT Appendix B: Results for DNT Appendix C: Results for RDX Appendix D : Results for HMX Appendix E: Characteristics of Quik-Gel, Aqua-Gel and well water
    In: CRREL Report, 85-18
    Sprache: Englisch
    Schlagwort(e): Forschungsbericht
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  • 7
    UID:
    kobvindex_GFZ20201202132526
    Umfang: iv, 12, [2] Seiten , Illustrationen
    Serie: Research report / Cold Regions Research and Engineering Laboratory 59
    Inhalt: Summary: The deflection expression of an infinite plate subjected to a concentrated force is used with the "method of images" to obtain solutions for 6 plates with simply supported edges. The semi-infinite plate, the wedge-shaped plate, and its special case, the rectangular corner plate, are solved in closed form; and the infinite strip, the semi-infinite strip, and the rectangular plate are solved as rapidly convergent series. Behavior under a concentrated force is studied in more detail for the semi-infinite plate and the rectangular corner plate. Relationships for obtaining bending moments, shear forces and reaction distributions as well as derivatives of the kei-function with respect to ? and ? are given in the appendices.
    Anmerkung: CONTENTS Preface Introduction and statement of the problem Solution of the boundary value problems for simply supported boundaries Semi-infinite plate Wedge-shaped plate Rectangular corner plate Infinite strip Semi-infinite strip Rectangular plate Remarks on the problem of arbitrary load distribution References Appendix A Appendix B
    In: Research report / Cold Regions Research and Engineering Laboratory, 59
    Sprache: Englisch
    Schlagwort(e): Forschungsbericht
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  • 8
    UID:
    kobvindex_GFZ20190723115656
    Umfang: iii, 21 Seiten , Illustrationen
    Serie: CRREL Report 88-1
    Inhalt: The Cornish-Windsor bridge is the longest covered bridge in the United States and has significant historical value. At a large peak flow, dynamic ice breakup of the Connecticut River can threaten the bridge and cause flood damage in the town of Windsor, Vermont. Throughout the 1985-86 winter we regularly monitored ice conditions, including a midwinter dynamic ice breakup on 27 January. We conducted controlled release tests over the operating range of the turbines at Wilder Dam upstream during both open water and ice cover conditions. These data and observations were analyzed in light of more than 60 years of temperature and discharge records. Our analysis indicates that river regulation presents alternatives for ice management that would minimize the probability of bridge damage and flooding during breakup. The flow can be regulated early in the winter to promote the growth of a stable ice cover, minimizing the total ice production in the reach. In the weeks prior to breakup, sustained releases and above-freezing air temperatures cause melting, weakening and gradual breakup of the ice, greatly reducing the flooding potential. Also, it is possible to produce a controlled ice breakup prior to an imminent natural event at lower stage and discharge. All of these ice control alternatives have associated power production costs.
    Anmerkung: CONTENTS Abstract Preface Introduction Background Analysis of historical data Field observations Controlled release tests January 1986 ice breakup Connecticut River ice control Minimizing ice production Hydrothermal melting Controlled ice breakup Conclusions Literature cited Appendix A: Detailed ice breakup chronology
    In: CRREL Report, 88-1
    Sprache: Englisch
    Schlagwort(e): Forschungsbericht
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  • 9
    Buch
    Buch
    Wilmette, Ill. : Snow Ice and Permafrost Research Establishment, Corps of Engineers, U.S. Army
    Dazugehörige Titel
    UID:
    kobvindex_GFZ20201110144344
    Umfang: iv, 20, [2] Seiten , Illustrationen , 27 cm
    Serie: Research report / Cold Regions Research and Engineering Laboratory 19
    Inhalt: Abstract: Measurements were made of global and net radiation between 6 July and 7 August 1955 at a site on the Greenland Ice Cap located near 78°N latitude and at an elevation of 6800 ft. Snow-surface temperatures during this period were below 0°C and mean cloudiness was 0.7. Total incident global radiation measured during the 33-day period amounted to 20,628 ?? of which only 3059 ??, or about 15%, were absorbed by the snow cover. Most of the absorbed global radiation was re-emitted as long-wave radiation, so the net gain during the observation period amounted to not more than 7.6 ??/day. Diffuse sky radiation amounted to only 19% of all incoming global radiation measured at the ice-cap research site. In the temperate zone, diffuse sky radiation amounts to 30% or more of the incoming radiation. The small amount of diffuse sky radiation indicates low atmospheric turbidity in this polar climatic zone. Incident global radiation was reduced by 6% in the presence of a 0.5 cloud cover. Under full overcast conditions the snow surface received 65% of the global radiation measured on clear days. In the temperate zone as little as 30% of global radiation reaches the earth under full cloud cover. The large amount of global radiation received in the Arctic under full cloud cover is the primary cause of one form of arctic white-out. Accompanying the small decrease in global radiation caused by cloudiness is a large decrease in effective outgoing long-wave radiation, with an increase in the net radiation balance. This condition contributes to a greater potential ablation of the snow and ice cover during cloudy seasons. The long-wave radiation balance at this site on the ice cap was always negative during the period covered by this study. Errors associated with the measurement of solar radiation at the low sun angles which prevailed at the research site were found to be about -3%. No correction was applied to the basic data, however, since there were insufficient data to establish the consistency of this error over the period of observation. During periods of blowing and drifting snow, 6% more global radiation was measured at 1.25 m above the snow surface than at 5.7 m elevation. The increase may be due to multiple reflection within the layer of blowing snow. The atmospheric transmission coefficient at the ice-cap site was found to be 0.968. This high value was associated with the low atmospheric turbidity. The heat balance of the snow cover as computed from the radiation measurements and a temperature profile in the snow was found to be 7.6 ??/day at the ice-cap site. This is a negligible heat gain when compared with the 400 ??/day gain by a spring snow pack in the Sierra Nevada of California. For the entire season when the sun is above the horizon, the estimated net gain by the ice cap is 1000 ??, no more than a 2-1/2-day heat supply used in melting the snow of the High Sierra. Some measurements made with a silicon solar battery similar to those developed by the Bell Telephone Laboratories indicate that it may have a significantly higher efficiency on the ice cap than in the more temperate zone. Verification of this apparent increase in efficiency and the causes for it require further study of the performance of the p-n junction cells in the Arctic.
    Anmerkung: CONTENTS I. Introduction II. Instrumentation Recording of data III. Results Global radiation Albedo of snow Diffuse sky radiation Effect of clouds on radiation Atmospheric and terrestrial radiation Effect of low sun angle on measured radiation Global radiation gradient Atmospheric transmission coefficient Heat balance of snow cover Applied use of solar energy References. Appendix
    In: Research report / Cold Regions Research and Engineering Laboratory, 19
    Sprache: Englisch
    Schlagwort(e): Forschungsbericht
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  • 10
    UID:
    kobvindex_GFZ20190723114646
    Umfang: v, 50 Seiten , Illustrationen
    Serie: CRREL Report 87-21
    Inhalt: The author measured time series of longitudinal (u) and vertical (w) velocity and temperature (t) and humidity (q) fluctuations with fast-responding sensors in the near-neutrally stable surface layer over a snow-covered field. These series yielded individual spectra and u-w, w-t, w-q and t-q cospectra, phase spectra and coherence spectra for nondimensional frequencies (fz/U) from roughly 0.001 to 10. With the exception of the u-w cospectra, all the spectra and cospectra displayed the expected dependence on frequency in an inertial or inertial-convective subrange. All, however, contained significantly more energy at low frequency than the Kansas neutral-stability spectra and cospectra. This excess low-frequency energy and the erratic behavior of the u-w cospectra imply that forested hills bordering the site on two sides were producing disturbances in the flow field at scales roughly equal to the height of the hills, 100 m. The phase and coherence spectra suggest that internal gravity waves were also frequently present, since the atmospheric boundary layer generally had slightly stable stratification. Consequently, at this complex site, turbulence alone determines the spectra and cospectra at high frequency; at low frequency the spectra and cospectra reflect a combination of topographically generated turbulence and internal waves. From the measured temperature and humidity spectra and the t-q cospectra, the author computed refractive index spectra for light of 0.55-micrometer and millimeter wavelengths. The refractive index spectra had shapes like the other scalar spectra: excess energy at low frequency and an inertial-convective subrange at high frequency.
    Anmerkung: CONTENTS Abstract Preface Introduction Measurements Spectra u and w velocity spectra Temperature and humidity spectra Inertial-dissipation estimates Cospectra u-w cospectra w-t and w-q cospectra t-q cospectra Refractive index spectra Conclusions Literature cited
    In: CRREL Report, 87-21
    Sprache: Englisch
    Schlagwort(e): Forschungsbericht
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