Soil Mixer for a Wide Range of Water Contents

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Konnerup-Madsen, J. (2001). A review of the composition and evolution of hydrocarbon gases during solidification of the Ilímaussaq alkaline complex, South Greenland. Geology of Greenland Survey Bulletin, 190, 159-166. https://doi.org/10.34194/ggub.v190.5187 _______________ Fluid inclusions in minerals from agpaitic nepheline syenites and hydrothermal veins in the Ilímaussaq complex and in similar agpaitic complexes on the Kola Peninsula, Russia, are dominated by hydrocarbon gases (predominantly methane) and hydrogen. Such volatile compositions differ considerably from those of most other igneous rocks and their formation and entrapment in minerals reflects low oxygen fugacities and a wide range of crystallisation temperatures extending to a low-temperature solidus. Their composition reflects initial low carbon contents and high water contents of the magma resulting in the exsolution of a waterrich CO2–H2O dominated vapour phase. Fractionation of chlorides into the vapour phase results in high salinities and the subsequent development of a heterogeneous vapour phase with a highly saline aqueous-rich fraction and a methane-dominated fraction, with preferential entrapment of the latter, possibly due to different wetting characteristics. The light stable isotope compositions support an abiogenic origin for the hydrocarbons in agpaitic nepheline syenite complexes.

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Compressibility behaviour of remoulded, fine-grained soils and correlation with index properties

Canadian Geotechnical Journal ◽

10.1139/t99-128 ◽

2000 ◽

Vol 37 (3) ◽

pp. 712-722 ◽

Cited By ~ 93

Author(s):

A Sridharan ◽

H B Nagaraj

Keyword(s):

Liquid Limit ◽

Plasticity Index ◽

Engineering Properties ◽

Test Results ◽

Index Properties ◽

Initial Water ◽

Fine Grained ◽

Wide Range ◽

The Relationship ◽

Water Contents

Correlating engineering properties with index properties has assumed greater significance in the recent past in the field of geotechnical engineering. Although attempts have been made in the past to correlate compressibility with various index properties individually, all the properties affecting compressibility behaviour have not been considered together in any single study to examine which index property of the soil correlates best with compressibility behaviour, especially within a set of test results. In the present study, 10 soils covering a sufficiently wide range of liquid limit, plastic limit, and shrinkage limit were selected and conventional consolidation tests were carried out starting with their initial water contents almost equal to their respective liquid limits. The compressibility behaviour is vastly different for pairs of soils having nearly the same liquid limit, but different plasticity characteristics. The relationship between void ratio and consolidation pressure is more closely related to the shrinkage index (shrinkage index = liquid limit - shrinkage limit) than to the plasticity index. Wide variations are seen with the liquid limit. For the soils investigated, the compression index relates better with the shrinkage index than with the plasticity index or liquid limit.Key words: Atterberg limits, classification, clays, compressibility, laboratory tests.

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The undrained strength of some thawed permafrost soils

Canadian Geotechnical Journal ◽

10.1139/t79-044 ◽

1979 ◽

Vol 16 (2) ◽

pp. 420-427

Author(s):

John F. Nixon ◽

Alan J. Hanna

Keyword(s):

Undrained Shear Strength ◽

Soil Types ◽

Density Range ◽

Mackenzie Delta ◽

Sample Depth ◽

Wide Range ◽

Permafrost Soils ◽

Undrained Strength ◽

Water Contents ◽

Undrained Shear

A large number of undrained shear strengths have been measured for thawed, undrained permafrost samples obtained from the Niglintgak Peninsula area of the Mackenzie Delta, N.W.T. The samples are mostly deltaic silts, with a few clay tills, and cover a wide range of depths, water contents, and frozen density. The undrained shear strengths of the thawed samples have been correlated with water content, frozen density, and sample depth. For these soil types, the strength is shown to decrease to zero at frozen densities of less than about 1670 kg/m3 and at water contents greater than about 35–42%. In the Niglintgak area, the undrained shear strength of the thawed samples below a depth of 10 m becomes relatively constant in the range of 23–43 kPa. This corresponds to a frozen density range of 1780–1870 kg/m3, and previous experience with soils of this nature indicates that the corresponding thaw settlement at these depths would be less than 10%.

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Effects of water content and temperature on the surface conductivity of bentonite clay

Soil Research ◽

10.1071/sr11228 ◽

2012 ◽

Vol 50 (1) ◽

pp. 44 ◽

Cited By ~ 2

Author(s):

M. A. Mojid ◽

H. Cho

Keyword(s):

Water Content ◽

Bentonite Clay ◽

Ionic Mobility ◽

Surface Conductivity ◽

Temperature Correction ◽

Hydration Layer ◽

Temperature Range ◽

Wide Range ◽

Hydration Layers ◽

Water Contents

This study explored the effects of water content and temperature on the mobility of exchangeable cations (termed the surface ionic mobility and hereafter ionic mobility) in the hydration layers of bentonite clay. The ionic mobility directly governs the surface conductivity of the clay. The investigation was done by measuring the bulk electrical conductivity (EC) of four sand–bentonite mixtures of different proportions for a wide range of water contents under constant temperature, and three bentonite samples at different water contents over 5–90°C. The ionic mobility was determined from the surface conductivity at the mean ionic strength of the hydration layers. The ionic mobility in the sand–bentonite samples increased with an increase in hydration layer thickness. For a given thickness of the hydration layer, the greater the bentonite content of a sample, the smaller was the ionic mobility. The ionic mobility in the bentonite samples at different water contents also increased, at reduced rates, with a rise in temperature. Consequently, the surface conductivity of the samples increased non-uniformly, at two different rates, with an increase in temperature. The increasing rate of this conductivity depended on temperature; over the low temperature range which depended on the water content, the rate was 0.013 dS/m.K, and over higher temperature range, the rate decreased to 0.008 dS/m.K. The commonly used temperature correction factor, 0.019 dS/m.K, for EC therefore did not hold true for the bentonite samples.

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WATER TOLERANCE OF MIXTURES OF GASOLINE WITH ETHYL ALCOHOL, ISOPROPYL ALCOHOL AND BENZENE

Canadian Journal of Research ◽

10.1139/cjr34-108 ◽

1934 ◽

Vol 11 (4) ◽

pp. 505-519

Author(s):

Colin H. Bayley ◽

Clarence Yardley Hopkins

Keyword(s):

Water Content ◽

Ethyl Alcohol ◽

Isopropyl Alcohol ◽

The Other ◽

Solution Temperature ◽

Critical Solution Temperature ◽

Water Tolerance ◽

Wide Range ◽

Critical Water Content ◽

Water Contents

The relation between water content and critical solution temperature of mixtures of gasoline with ethanol and isopropanol and with ethanol and benzene has been determined. Curves are presented which show the critical water contents of a wide range of mixtures at any temperature between + 20° and − 50 °C. Three gasolines were used, two being straight-run and one a cracked gasoline. The mixtures contained 60 to 90% of gasoline with varying proportions of the other two components. Isopropanol has been found to bring about a marked increase in the critical water content of gasoline-ethanol mixtures to which it is added. Benzene is shown to be of little value for this purpose within the range of mixtures studied.

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ANALYSIS OF EMPIRICAL COMPRESSION INDEX EQUATIONS USING THE WATER CONTENT

Proceedings of International Structural Engineering and Construction ◽

10.14455/isec.res.2017.62 ◽

2017 ◽

Vol 4 (1) ◽

Author(s):

Amir W. Al-Khafaji ◽

Krishnanand Y. Maillacheruvu ◽

Melissa Hoerber

Keyword(s):

Water Content ◽

Empirical Models ◽

Soil Types ◽

Data Sets ◽

Regression Equations ◽

Compression Index ◽

Empirical Formulas ◽

Wide Range ◽

Compression Data ◽

Water Contents

This paper proposes a new method to evaluate the reliability of published empirical formulas in terms of accuracy and applicability to different soil types. Different empirical models are proposed to properly approximate the compression index for a wide range of water contents and soil types. They were developed using a unique technique and a substantial number of published regression equations and compression data. Familiar empirical equations were examined for their reliability in predicting the compression index of clay for any water content. A comparison was made between available and newly-proposed empirical formulas using combined regression data sets compiled independently by several authors. The newly proposed empirical compression index equations are applicable to a wide range of clay soils, and in validating other published relationships. The degree of scatter and variations in the computed compression index values are minimized for any water content.

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Multifractal evaluation of simulated precipitation intensities from the COSMO NWP model

10.5194/acp-2017-73 ◽

2017 ◽

Author(s):

Daniel Wolfensberger ◽

Auguste Gires ◽

Ioulia Tchiguirinskaia ◽

Daniel Schertzer ◽

Alexis Berne

Keyword(s):

Multifractal Analysis ◽

Dominant Role ◽

Weather Prediction ◽

Time Variability ◽

Scale Invariant ◽

Simulated Precipitation ◽

Wide Range ◽

Spatio Temporal ◽

The Impact ◽

Water Contents

Abstract. The framework of universal multifractals allows to characterize the spatio-temporal variability of fields over a wide range of scales with only a limited number of scale-invariant parameters. In this work, we perform a multifractal analysis of simulated fields of water contents in liquid, solid and gas phase from the COSMO numerical weather prediction model during three different events (one cold front associated with heavy snowfall, one stationary front with stratiform rain and one summer convection event) over Switzerland. The multifractal parameters of precipitation intensities at the ground are also compared with those obtained from the Swiss radar composite. The results of the analysis show that the COSMO simulations exhibit spatial scaling breaks that are not present in the radar data, indicating that the model is not able to simulate the observed variability at all scales. The impact of the topography on these conclusions was assessed by comparing a very steep area to a mostly flat area. It was observed that the topography does not seem to play a dominant role in the multifractal characterization of the COSMO water contents. Additionally, a spatio-temporal multifractal analysis of the COSMO simulations and the radar composite was performed and compared with a simplified scaling model of space-time variability.

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An Examination of the Drought and Frost Tolerance of Banksia marginata (Proteaceae) as an Explanation of Its Current Widespread Occurrence in Tasmania

Australian Journal of Botany ◽

10.1071/bt9960265 ◽

1996 ◽

Vol 44 (3) ◽

pp. 265 ◽

Cited By ~ 4

Author(s):

J Blake ◽

RS Hill

Keyword(s):

Drought Tolerance ◽

Sea Level ◽

Frost Tolerance ◽

Population Variation ◽

Physiological Plasticity ◽

Widespread Occurrence ◽

Wide Range ◽

Cell Elasticity ◽

Insight Into ◽

Water Contents

Populations of Banksia marginata Cavanilles from sea level to 1040 m above sea level near Hobart were examined for frost and drought tolerance to determine the extent of the inter-population variation and physiological plasticity of this species. This study was designed to give some insight into the reasons behind the successful occupation of a wide range of habitats by B. marginata in Tasmania today. All populations were highly frost tolerant, irrespective of season, with the peak tolerance usually occurring in summer, suggesting a link to some other physiological aspect such as drought tolerance. Water relations results were complex and highly variable among the populations. For the highest altitude population at least it is probable that cell elasticity and high apoplastic water contents, rather than osmotic adjustment, assist in frost and drought tolerance. It is likely that the physiological plasticity and apparent genetic diversity exhibited by these populations assisted the survival of B. marginata in pockets of refugia throughout Tasmania during past climatic upheavals during glacial and interglacial cycles.

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Experimental temperature–X(H2O)–viscosity relationship for leucogranites and comparison with synthetic silicic liquids

Earth and Environmental Science Transactions of the Royal Society of Edinburgh ◽

10.1017/s0263593300000924 ◽

2004 ◽

Vol 95 (1-2) ◽

pp. 59-71 ◽

Cited By ~ 23

Author(s):

Alan Whittington ◽

Pascal Richet ◽

Harald Behrens ◽

François Holtz ◽

Bruno Scaillet

Keyword(s):

Configurational Entropy ◽

Liquid Composition ◽

Viscosity Data ◽

Entropy Theory ◽

Melt Structure ◽

Naturally Occurring ◽

Wide Range ◽

Compositional Variations ◽

Water Contents ◽

Magma Viscosity

ABSTRACTViscosities of liquid albite (NaAlSi3O8) and a Himalayan leucogranite were measured near the glass transition at a pressure of one atmosphere for water contents of 0, 2·8 and 3·4 wt.%. Measured viscosities range from 1013·8 Pa. s at 935 K to 109·0 Pa. s at 1119 K for anhydrous granite, and from 1010·2 Pa. s at 760 K to 1012·9 Pa. s at 658 K for granite containing 3·4 wt.% H2O. The leucogranite is the first naturally occurring liquid composition to be investigated over the wide range of T-X(H2O) conditions which may be encountered in both plutonic and volcanic settings. At typical magmatic temperatures of 750°C, the viscosity of the leucogranite is 1011·0 Pa. s for the anhydrous liquid, dropping to 106·5 Pa. s for a water content of 3 wt.% H2O. For the same temperature, the viscosity of liquid NaAlSi3O8 is reduced from 1012·2 to 106·3 Pa. s by the addition of 1·9 wt.% H2O. Combined with published high-temperature viscosity data, these results confirm that water reduces the viscosity of NaAlSi3O8 liquids to a much greater degree than that of natural leucogranitic liquids. Furthermore, the viscosity of NaAlSi3O8 liquid becomes substantially nonArrhenian at water contents as low as 1 wt.% H2O, while that of the leucogranite appears to remain close to Arrhenian to at least 3 wt.% H2O, and viscosity–temperature relationships for hydrous leucogranites must be nearly Arrhenian over a wide range of temperature and viscosity. Therefore, the viscosity of hydrous NaAlSi3O8 liquid does not provide a good model for natural granitic or rhyolitic liquids, especially at lower temperatures and water contents.Qualitatively, the differences can be explained in terms of configurational entropy theory because the addition of water should lead to higher entropies of mixing in simple model compositions than in complex natural compositions. This hypothesis also explains why the water reduces magma viscosity to a larger degree at low temperatures, and is consistent with published viscosity data for hydrous liquid compositions ranging from NaAlSi3O8 and synthetic haplogranites to natural samples. Therefore, predictive models of magma viscosity need to account for compositional variations in more detail than via simple approximations of the degree of polymerisation of the melt structure.

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Seed mass variation potentially masks a single critical water content in recalcitrant seeds

Seed Science Research ◽

10.1079/ssr2004168 ◽

2004 ◽

Vol 14 (2) ◽

pp. 185-195 ◽

Cited By ~ 21

Author(s):

Matthew I. Daws ◽

Christiane S. Gaméné ◽

Sheila M. Glidewell ◽

Hugh W. Pritchard

Keyword(s):

Water Content ◽

Seed Mass ◽

Tropical Tree ◽

Recalcitrant Seeds ◽

Seed Population ◽

Wide Range ◽

Critical Water Content ◽

Whole Seed ◽

Water Contents ◽

Seed Water Content

For recalcitrant seeds, mortality curves of germination versus water content typically imply a wide range of desiccation sensitivities within a seed population. However, seed to seed differences in water content, during desiccation, may confound our interpretation of these mortality plots. Here, we illustrate this problem for two batches ofVitellaria paradoxa(Sapotaceae) seeds collected in 1996 and 2002. Whole seeds were desiccated to various target water contents (TWCs) using silica gel. During desiccation, smaller seeds in the population dried most rapidly. Consequently, there was a significant linear relationship between whole-seed water content and seed mass during the drying process. In addition, following desiccation to low TWCs, only the largest seeds in the population retained viability. Taken together, this suggests that the larger seeds survived, not as a consequence of great relative desiccation tolerance, but as a result of taking longer to desiccate. Subsequently, the critical water content (CWC) for viability loss was calculated, based on the assumptions that in the seed population whole-seed water content during desiccation was normally distributed and the smallest, and hence driest, seeds were killed first. Using this approach, the driest seeds in the population that were killed, at each TWC, were always below a single CWC (c. 20% and 26% in 1996 and 2002, respectively). In subsequent experiments the effect of seed size variation on the response to desiccation was confirmed by conducting desiccation screens on seeds sorted into two discrete size classes, i.e. the seed-lot heterogeneity in mass was reduced. Using this approach, the mortality curves had a steeper slope. Furthermore, data for 24 tropical tree species from the Database of Tropical Tree Seed Research (DABATTS) revealed that seed lots with less variability in mass had steeper mortality curves. Thus, taken together, the data suggest that, at least for whole seeds, the wide range of desiccation sensitivities typically inferred is an artefact of seed to seed variation in mass, and hence water contents, during drying.

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