New data on the velocity of 10 MHz compressional waves in dulute solutions of potassium in liquid ammonia are presented. These data are not consistent with the existence of the reported volume expansion minimum. Compa...
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New data on the velocity of 10 MHz compressional waves in dulute solutions of potassium in liquid ammonia are presented. These data are not consistent with the existence of the reported volume expansion minimum. Comparison of this data with earlier data on more concentrated solutions shows that the concentration dependence of the sound velocity is quite similar to that exhibited by both the density and viscosity and is consistent with a model of the solutions proposed by Cohen and Thompson.
Literary Modernism and the Occult Tradition. Edited by Leon Surette and Demetres P. Tryphonopoulos. Orono, Maine: The National Poetry Foundation, 1996. Pp. 217 + xviii. $35.00 (cloth); $20.00 (paper).
Literary Modernism and the Occult Tradition. Edited by Leon Surette and Demetres P. Tryphonopoulos. Orono, Maine: The National Poetry Foundation, 1996. Pp. 217 + xviii. $35.00 (cloth); $20.00 (paper).
Thermal expansion coefficients (alpha), glass-transition (T-g) and Littleton (T-L) temperatures, hardness and density of the RE-Si-Mg-O-N glasses (RE = Se, Y, La, Nd, Sm, Gd, Yb, and Lu) were investigated to separate ...
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Thermal expansion coefficients (alpha), glass-transition (T-g) and Littleton (T-L) temperatures, hardness and density of the RE-Si-Mg-O-N glasses (RE = Se, Y, La, Nd, Sm, Gd, Yb, and Lu) were investigated to separate the effects of rare-earth elements and nitrogen on the properties of bulk glasses. These properties depend approximately linearly on nitrogen content, density of the glass and ionic radius of the corresponding lanthanide. Lanthanides modify hardness of the studied oxynitride glasses with 20-24 eq.% N by 11.4-14.4%, alpha by similar to13%, T-g by 31-35 degreesC, and T-L by 33-43 degreesC. Deviations from linearity found in Nd-, Sm- and Yb-doped glasses were possibly due to valence change. Non-lanthanide dopants, Sc and Y, often do not fit the dependence but result in comparable properties. The effects of nitrogen and rare-earth dopants are independent and additive. (C) 2003 Elsevier Ltd. All rights reserved.
In this paper, the contribution of visual and acoustic preference to multi-sensory landscape evaluation was quantitatively compared. The real landscapes were treated as dual-sensory ambiance and separated into visual ...
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In this paper, the contribution of visual and acoustic preference to multi-sensory landscape evaluation was quantitatively compared. The real landscapes were treated as dual-sensory ambiance and separated into visual landscape and soundscape. Both were evaluated by 63 respondents in laboratory conditions. The analysis of the relationship between respondent's visual and acoustic preference as well as their respective contribution to landscape preference showed that (1) some common attributes are universally identified in assessing visual, aural and audio-visual preference, such as naturalness or degree of human disturbance;(2) with acoustic and visual preferences as variables, a multi-variate linear regression model can satisfactorily predict landscape preference (R-2 = 0.740), while the coefficients of determination for a unitary linear regression model were 0.345 and 0.720 for visual and acoustic preference as predicting factors, respectively;(3) acoustic preference played a much more important role in landscape evaluation than visual preference in this study (the former is about 4.5 times of the latter), which strongly suggests a rethinking of the role of soundscape in environment perception research and landscape planning practice. (C) 2014 Acoustical Society of America.
This study was conducted in Melka Wakena catchment;south eastern Ethiopia to assess land use/cover change (LULCC) and topographic elevation effect on selected soil quality/fertility parameters. 144 soil samples collec...
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This study was conducted in Melka Wakena catchment;south eastern Ethiopia to assess land use/cover change (LULCC) and topographic elevation effect on selected soil quality/fertility parameters. 144 soil samples collected from 0 - 30 cm depth under three land cover types across three elevation gradients were analysed for selected soil quality/fertility parameters. Data were statistically analyzed using analysis of variance (ANOVA) and mean comparisons were made using Least Significant Difference (LSD). The soil properties examined generally showed significant variations with respect to land-use/land cover changes and elevation. Soil particles, soil organic carbon, total N, pH, available phosphorus, potassium and calcium content significantly decreased as forestland is converted into cropland/grassland. Heaviest soil deterioration was recorded in soils under cropland and followed by grassland soils. The conversion of natural forest to different land uses without proper soil conservation and management practices resulted in the overall decline of soil fertility quality. Thus, integrated land resource management approach is indispensable for sustaining agricultural productivity and the environmental health of the Melka Waken a catchment.
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