Shima Ramezani; Mohammad Talaeipoor; Misam Aliabadi; Asghar Tabeai; Behzad Bazyar
Abstract
Samples were prepared from the native poplar species (Populus alba) grown in Mehnan, a region in Bojnourd at the ages 5 and 25 and the anatomical, biometrical and chemical characteristics of the samples sections in three directions (cross section, radial and tangential) of the tree were measured. ...
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Samples were prepared from the native poplar species (Populus alba) grown in Mehnan, a region in Bojnourd at the ages 5 and 25 and the anatomical, biometrical and chemical characteristics of the samples sections in three directions (cross section, radial and tangential) of the tree were measured. Dioxan and Klason lignin were measured. Structural similarities in vascular cavities or impacted vessels in the form of binary, tripple or tetraploidy groups in juvenile and mature wood was observed primarily in radial direction. Fiber length and cell wall thickness variation in the juvenile and mature wood was significantly different and as the age of the tree increases, such difference is more significant. This point need to be considered by cellulose industries. As the age of the tree increase and the wood matures, significant change in vessel size in samples from 5 or 25 years old trees was not detected. The result showed that the older wood contains lower content of extractive and lignin and higher content of cellulose
Physics and anatomy
Meisam Aliabadi; Eiman Akbarpoor; Ahmadreza Saraeyan; Jalil Roshnasan
Abstract
This research was performed to investigate fiber biometrical properties (length, diameter and fiber thickness) of hornbeam species from Astara in Iran. Initially, disks were prepared with three trees of hornbeam species and then fiber isolation was carried out using Franklin method. Length, diameter ...
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This research was performed to investigate fiber biometrical properties (length, diameter and fiber thickness) of hornbeam species from Astara in Iran. Initially, disks were prepared with three trees of hornbeam species and then fiber isolation was carried out using Franklin method. Length, diameter and wall thickness of fiber provided were determined by laboratory microscope using eye scaled lens. The measurement of fiber dimensions was made at the pith region and at the distances of 2,6,12 and 15 centimeters and four geographical sides. The results indicated that length, diameter and wall thickness of fiber increased significantly with enhance of distance from pith. The highest fiber length, diameter and wall thickness obtained were 1.509 mm, 23.93 µm and 3.897 µm, respectively. The consequences attained from changing of fiber dimensions at various distances from pith to bark indicated that fiber dimensions change decreased by increase in distance from pith up to 15 cm and the highest change of fiber was observed at distance of 2-6 cm from pith. The results of measuring the fiber dimensions at various geographical sides didn't indicate any significant deference between the values of fiber length, diameter and wall thickness at 1% level of probability. The combined effects of distance from pith and different geographical sides also did not show any significant deference on fiber dimensions.
Meisam Aliabadi; Eiman Akbaepoor; Ahmad reza Saraeian
Abstract
In this study, the effect of organic complex "sulvy-x" on the optical properties of hornbeam CMP pulp bleached with hydrogen peroxide was investigated. Sulvy-x was used in two sequences silicate-free and silicate containing in hydrogen peroxide bleaching. The brightness of papers increased to 60.52 and ...
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In this study, the effect of organic complex "sulvy-x" on the optical properties of hornbeam CMP pulp bleached with hydrogen peroxide was investigated. Sulvy-x was used in two sequences silicate-free and silicate containing in hydrogen peroxide bleaching. The brightness of papers increased to 60.52 and the yellowness decreased to 22.6 with increasing silicate charges up to 1% . However, at higher levels than 1% , the brightness decreased and the yellowness increased. Without dosage of sodium silicate but using 0.5% of sulvy-x, maximum brightness of 59.3% and minimum yellowness of 23.4 % ISO was achieved. In silicate-containing bleaching, combination of 0.5% sulvy-x and 0.7% sodium silicate resulted the highest brightness (60.28 % ISO) and the lowest yellowness (23 % ISO). Optimum charge of sodium hydroxide and hydrogen peroxide were determined as 2.5% and 5%.The best time for bleaching of hornbeam CMP pulp was 90 minutes in either sequences. With regard to results obtained, utilization of the organic complex of sulvy-x could be a suitable substitution for sodium silicate which produces the pulp with higher brightness and lower yellowness in conventional peroxide bleaching.
