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EN
Finding a thermal insulation material that is naturally available, cheap, and effective for minimising energy losses is a challenge for geotechnical engineers in Jordan. Previous research suggests the use of mineral wool, polyurethane, or air layers as an insulation material but so far, the basalt has not been used as an insulation material in Jordan. The objective of this study was to measure and compare the thermal conductivity (K), bulk density (ρB ), porosity (ɛ) and chemical composition of the basalt from Hashemiah area and Hulial mountain in Jordan in order to evaluate the rock as a thermal insulation material. A total of fourteen samples, seven for each zone, were evaluated. The thermal conductivity was measured using transient plane source technique (TPS) at ambient temperature. Porosity and density were measured by the standards of the American Society of Testing Materials (ASTM). The chemical composition of the samples was analysed by X-Ray diffraction to include the effect of aluminium oxide on thermal conductivity analysis. Experimental values covered the range of ɛ between 0.008–8.7%; ρB between 2.54–2.93 g/cm3 and K between 1.62–2.98 W/mK. The experimental K values were compared with allometric fit and theoretical prediction models. In general, thermal conductivity tends to decrease with porosity in basalt samples. This study found increasing conductivity values with ɛ when ferromagnesian-aluminium oxide concentration reached levels above 38% and porosity less than 4% indicating that high percentages of these oxides decrease the insulating effect of the air in the empty spaces of the basalt at reduced porosity levels. Low values of conductivity and percentage of ferromagnesianaluminium oxides characterise the Jordanian basalt in the Hashemiah area and makes it better for insulation than the Hulial mountain basalt. The experimental values presented in this work are important for predicting the optimum insulation thickness and predicting energy losses in construction buildings where basaltic rocks are used.
EN
Fortunella margarita is an excellent source of acids, sugars and phenolic compounds, the cultivation of which has become popular in Jordan in the last few years. The aim was to observe the quality of the kumquat fruits cultivated in Irbid and the Ghor Valley. Physical properties such as size, density, sphericity, porosity and color were measured. Total titrable acidity (TTA), total soluble solids (TSS), Ascorbic Acid (AA), pH and phenolic compounds were evaluated in the pulp-rind extract. Total phenols (TPC), flavonoids and carotenoids were measured by spectrophotometry at 765, 430 and 470–664 nm, respectively. High porosity (67%), fruit size (37.4 mm) and juice yield (25.5%) were achieved in the Ghor kumquat crop. The high levels of TPC (2039.2 mg GAE/100 g), AA (0.361 mg/ml) and carotenoids (1.15 mg/100 g) registered in this same crop, attribute it better functional and medicinal properties. Moreover, the Ghor cultivation presented better taste, associated with high values of pH (3.47), TSS (5%) and low levels of TTA (1.55%). The high concentration of total carotenoids recorded in the Ghor’s kumquat was associated with the intense and bright orange color of its rind, related with high values of the color coordinates + a, + b and L of the CIELab system. The great porosity of its rind, makes the kumquat a suitable fruit for impregnating with salt or sugar solutions as well as developing new kumquat products with better flavor and nutritional value. The ranges found in the properties of kumquat crops, are attributed to the different temperatures of Ghor and Irbid.
EN
Punica granatum L. study is interesting for the functional properties associated to its Phenolic compounds and high volumes of production of this fruit in Jordan. The pomegranate type "pale arils" from Abu Ziyad valley were evaluated during different stages between 20 to 140 days after full bloom, with techniques of chelation, colorimetry and spectrophotometry. The results show that the increasing of sphericity (0.79 to 0.91), size diameter (65.58 to 90.41 mm), juice yield (46.03 to 55.67%), arils mass (31.70 to 61.23%), TSS total soluble solids (11.01 to 16.80), pH (2.7 to 3.6) and anthocyanins (7.43 to 12.41 Cyannidine 3 glucoside/100 g) were associated with the decreasing of thickness of the rind (4.9 to 2.77 mm), TTA Titrable total acidity (3.5 to 1.1%), TPC Total phenolics (389.61 to 251.52 mg Gallic acid/100 g), flavonoids (0.73 to 0.40 mg Catechine/g), tannins (8940.11 to 3324.79 ppm), AA Antioxidant Activity (63.41 to 48.84%) and Ascorbic acid content (28.91 to 9.48 mg/100 g); presenting significant differences p≥0,5. The paleness of rind and arils is positively related to the anthocyanin content expressed by "a" and "C" color coordinates. The actual investigation demonstrates that high values TSS-pH, low content of tannins and TTA could be successfully indicators of maturity stages rather than the concentration of anthocyanins.
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