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Slender reed straws in nature can withstand heavy weight of reed spikes and lateral wind force, and thus show good mechanical properties, especially compression resistance and shear resistance. In the paper, the quasistatic and dynamic mechanical properties of reed straws were studied. Three influencing factors of the straws were set according to the nodes (node-containing, node-free), location section (location 1, 2, 3, 4, 5), and moisture content (low, medium, high). The tensile strength of node-free reed straws with low moisture content ranged from 55.40 to 68.14 MPa at different locations. The axial compressive strength of node-containing straws was higher than that of node-free straws, and the influence of moisture content on the axial compressive strength was more obvious. The radial compressive strength of node-containing straws is 13.00 times higher than that of node-free straws in the corresponding part. The bending strength of straws gradually increases from the top to the root, and it is further enhanced with higher moisture content. The axial impact peak load of nodecontaining straws is up to 1.27 times that of node-free straws, and the axial impact peak load of straws with high moisture content is 1.40 times higher than that of straws with low moisture content in the corresponding part. The radial impact strength of reed straws gradually increases from the top to the root. In terms of bending impact strength, the impact toughness of reed straws ranges from 0.030 to 0.14 J·cm2, and the specific energy absorption ranges from 1.09 to 4.35 J/kg. Because of the excellent mechanical properties, reed straws provide important material performance data for the engineering field and inspire the design of new engineering materials or structures by improving strength and reducing weight. [ABSTRACT FROM AUTHOR]

The present study aimed to evaluate an available process for production of ferulic acid (FA) and p-coumaric acid (pCA) that could be potentially used as functional agents in food processing. The hydrothermal pretreatment combined with enzymatic hydrolysis (HP-CEH) was explored for efficient production of phenolic acids from reed straws. The results indicated that HP-CEH significantly increased production of phenolic acids. The recovery yield of ferulic acid and p-coumaric acid was respectively found to be 0.69 and 0.81 mig/g dry reed straw when performed by HP-CEH for 16 h. The degradation of hemicellulose, lignocellulose and lignin, and disruption of cell walls or cellulose fibers contributed to phenolic acids production from reed straws. Moreover, the scavenging activity of hydroxyl radical and DPPH radical of the phenolic acids extracted by HP-CEH was respectively obtained to be 77.32% and 86.77%. [ABSTRACT FROM AUTHOR]

To explore the effects of absorbed dose and particle size on enzymatic hydrolysis and fermentation of reed straws (Phragmites australias), the straws were irradiated with γ-ray irradiation at different doses (0-500 kGy) and then passed through different aperture sieves after mechanical grinding. The effects of absorbed doses and sieving aperture size on particle size distribution, comminution energy, main component content, enzymatic hydrolysis conversion rate, and ethanol conversion rate of cellulose were examined, and the optimal respective sieving aperture for reed straws with different absorbed doses were determined. The results showed that with decreasing sieve aperture size, reed straw quality decreased significantly and was negatively correlated with the absorbed dose; the comminution energy of reed straws decreased with increasing absorbed doses. With respect to consistent quality of sieved reed straws, the comminution energy increased significantly with decreasing sieving particle size. In reed straws with the same absorbed dose, the enzymatic hydrolysis conversion rate and ethanol conversion rate of cellulose increased with decreasing sieving aperture size. Compared with reed straws with particle size r ˂ 0.850 mm, the cellulose enzymatic hydrolysis conversion rates in reed straws with particle size r ˂ 0.180 mm increased by 129.20%, 85.98%, and 106.63% at absorbed doses of 0 kGy, 206 kGy, and 404 kGy, respectively, and cellulose ethanol conversion increased by 136.04%, 21.75%, and 4.39%, respectively. By compre- hensively comparing the increased ratios of comminution energy, cellulose enzymatic hydrolysis conversion rate, and cellulose ethanol conversion rate, the optimal sieving aperture of non-irradiated (0 kGy) reed straws was deter-mined to be 0.850 mm, and that of reed straws irradiated with 206 kGy or 404 kGy was determined to be 0.425 mm.

The research presented in this paper proposes structures of timber frame exterior walls using reed straws as insulation materials. Having thicknesses of 175 mm and designed for exterior building walls, the proposed structures are composed of 12-mm-thick oriented strand board, 150-mm-thick insulation material with and without air layers, a vapour barrier foil and 12.5-mm-thick gypsum board for the interior face of the wall. The insulation materials used as reference for the proposed structures are polystyrene and rock wool. Reed straws used as insulation material for the tested wall structures formed insulation layers of 150 mm thickness in five configurations: 150-mm loose-fill reed straws without air layer and other four variants with loose-fill reed straws and 100-, 50-, 20- and 10-mm-thick air layers, respectively. The air layer was placed at the contact with gypsum board for all configurations. The reference structures (rock wool and polystyrene as insulation materials) followed three of the configurations set-up, namely 150-mm-thick insulation material (rock wool or polystyrene) only and insulation materials with air layers thicknesses of 100 and 50 mm, respectively. The eleven tested structures were subjected to thermal conductivity coefficient (λ) measurements. The tests were performed on HFM436 Lambda equipment. The structures were tested for an entire cycle of temperatures varying between − 10 and 30 °C and thus simulating summer and winter climate conditions. The thermal conductivity coefficient of the exterior walls filled with loose reed straws as insulation material was recorded between mean values of 0.076 and 0.077 W m−1 K−1, except the structure with an air layer of 100 mm, for which a value of 0.120 W m−1 K−1 was registered. [ABSTRACT FROM AUTHOR]