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91.
A solar heated experimental drying kiln was installed in Madrid (INIA-Forest Industries Department) to study the efficiency of solar drying of sawn lumber in Spain, as compared with normal air drying. The kiln has been designed as a low cost semi-greenhouse type, but was equipped with a semi-automated control of the drying schedules. The performance of the solar kiln has been studied during ten test runs over a period of two years particularly with respect to drying rate, initial and final wood MC, reliability and efficiency. The results have proven that the solar kiln is capable of drying (economically) from an initial moisture content of 70 to 80%, to a final MC of 8 to 10% up to 3.5 times faster than air drying. With respect to checks, splits and internal stresses, the final wood quality is mostly better, not only compared to normal air drying but also to conventional kiln drying. 相似文献
92.
Andrés H. Fernández-Barrera Daniel Castro-Fresno Jorge Rodríguez-Hernández Miguel A. Calzada-Pérez 《Canadian Metallurgical Quarterly》2008,134(5):659-665
This paper presents the Cantabrian portable infiltrometer (CP infiltrometer), a specially designed device based on rainfall simulation for the assessment of the infiltration capacity of all types of urban pavements. Several pervious and impervious surfaces were tested with the LCS permeameter, an existing infiltration test based on the use of a column of water, and the CP Infiltrometer, simulating rain intensities with return periods of 10, 50, and 500 years and 5?min duration. The discussion of the results indicates that the CP infiltrometer could be used successfully to identify different levels of infiltration capacity and to assess the correct performance of pervious surfaces on which design, construction, and maintenance decisions are based. 相似文献
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95.
Erythrocytes express the same glucose transporter (GLUT-1) as is present in the blood-brain barrier. With the aim of testing the viability of using this transport system to deliver glucosyl drug derivatives to the brain, the uptake of several dopamine-glucose conjugates and a few structurally related analogues by erythrocytes was studied with HPLC and (1)H MAS NMR spectroscopy. The results showed that slight structural changes determine the uptake of glycoconjugates by red blood cells. However, experiments in the presence of glucose transport inhibitors showed that none of the conjugates that efficiently crossed the cell membrane were transported by GLUT-1. 相似文献
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97.
D. García-López I. Gobernado-Mitre J. F. Fernández J. C. Merino J. M. Pastor 《Polymer Bulletin》2009,62(6):791-800
Nanocomposites based on polyamide 6 have been directly prepared by melt compounding, using modified low cost bentonites by
three selected quaternary ammonium cations, in particular quaternized octadecylamine (ODA), dimethyl benzyl hydrogenated tallow
quaternary ammonium (B2MTH) and dimethyl hydrogenated ditallow quaternary ammonium (2M2TH). Thermal stability of organic modifiers
and organoclays has been studied by TGA and results allow evaluating the degree of modifier incorporation into clay galleries.
The influence of the organic modifier on the morphology and properties of the obtained nanocomposites has been studied by
X-ray diffraction and TEM analysis. Depending on the degree of bentonite modification, different mechanisms were reported
to explain the improved mechanical properties of the resulting nanocomposites. 相似文献
98.
Louis de Grange Enrique Fernández Joaquín de Cea Magdalena Irrazábal 《Networks and Spatial Economics》2010,10(4):551-578
A methodology is proposed for estimating a combined transportation model that accommodates spatial aggregation. It employs maximum likelihood estimation using a joint probability function that includes destination and mode choice simultaneously. The main contribution of the paper is the incorporation of a spatial aggregation strategy to validate the method when the survey data are insufficient. By aggregating small zones into larger districts, estimation of the trip distribution parameters can be achieved with limited data, while mode choice continues to be estimated using disaggregated data. Our results demonstrate that including trip distribution in the travel decision induces variations in the utility function parameter estimators obtained for the different travel modes when only mode choice is estimated. The methodology thus corrects omission bias. 相似文献
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100.
Álvaro Fernández‐Cuesta José M. Fernández‐Martínez Rafel Socias i Company Leonardo Velasco 《European Journal of Lipid Science and Technology》2013,115(2):211-216
Almond kernels show large variability for oil content and fatty acid profile. The objective of this research was to evaluate the potential of near infrared (NIR) reflectance spectroscopy (NIRS) for the analysis of these traits in almond flour. Ground kernels of 181 accessions collected in 2009 were used for developing calibration equations for oil content and concentrations of individual fatty acids. Calibration equations were developed using second derivative transformation and modified partial least squares regression. They were validated with samples from 179 accessions collected in 2010. The accuracy of calibration equations was measured through the coefficient of determination (r2) in external validation and the ratio of the SD in the validation set to the standard error of prediction (RPD). Both r2 and RPD were high for oil content (r2 = 0.99; RPD = 9.24) and concentrations of oleic (r2 = 0.97; RPD = 5.37) and linoleic acids (r2 = 0.98; RPD = 7.35), revealing that calibration equations for these traits are highly accurate. Conversely, the accuracy of the calibration equations for palmitic (r2 = 0.54; RPD = 1.41) and stearic acids (r2 = 0.52; RPD = 1.44) was too low for allowing their application in practice. NIRS discrimination of oil content and concentrations of oleic and linoleic acids was mainly based on the spectral region from 2240 to 2380 nm. Practical applications : NIRS is a high‐throughput analytical technique that allows fast measurement of several traits in a single analysis without using chemical reagents. We evaluated the feasibility of analyzing oil content and concentrations of palmitic, stearic, oleic, and linoleic acids in almond flour using fruits collected during 2 years from a world germplasm collection. The fruits collected in 2009 were used for NIRS calibration, whereas the fruits collected in 2010 were used for validation. NIRS equations were highly accurate for measuring oil content and concentrations of oleic and linoleic acids, which are important traits defining the quality of almond flour for specific uses in the food industry. These results have applications both in the research laboratory and the food industry, where NIRS is becoming a widely used technique for quality control. 相似文献