Smoothness of paper surface is an important property from its printability. A number of techniques are available for characterizing the topographical features of the paper surface. These techniques have led to the development of smoothness testers of various types such as airleak testers, optical contact testers, surface profilers, and a number of ink and liquid application apparatus to assess ...

Thirteen fatty acids were identified from the pulps of four Tunisian Ziziphus jujuba ecotypes (Sfax, Choutrana, Mahres and Mahdia), using capillary gaseous chromatography method. These oils presented 8.31% to 12.35% of dry weights. Compared to the other ecotypes, Mahres and Choutrana were the richest of the oleic acid. The palmitic acid was the most important compound of the Sfax ecotype. Unsat...

Common metrics for evaluating the efficiency of oxygen delignification include the kappa number and Klason lignin content. As a change in xylan content often leads to a change in HexA content, the kappa number must be corrected for the HexA contribution before evaluating the degree of oxygen delignification when trying to understand the process in detail. Questions could also be raised about th...

Films of microfibrillated celluloses (MFCs) from pulps of different yields, containing varying amounts of extractives, lignin, and hemicelluloses, were produced by combining refining and high-pressure homogenization techniques. MFC films were produced using a casting-evaporation technique and the physical and mechanical properties (including density, roughness, fold endurance and tensile proper...

In this research, hornbeam chips were cooked under chemimechanical pulp (CMP) conditions, and the pulps were prepared at a yield level of 85%. The CMP pulps were separately bleached with hydrogen peroxide and sodium dithionite with and without treatment with DTPA. Then 60 gr/m 2 handsheets were made. The goal was to determine whether complementary bleaching with sodium dithionite improves optic...

The chemical composition of lipids from bast fibers of flax (Linum usitatissimum), which are commonly used for high-quality paper pulp production, was thoroughly studied by gas chromatography-mass spectrometry. The main compounds identified were waxes, series of long chain n-fatty alcohols, n-aldehydes, n-fatty acids, and n-alkanes. Free and esterified sterols and triterpenols, steroid hydrocar...

The reliable and accurate determination of oxidized functionalities in cellulosic substrates still represents a largely unsolved problem in cellulose chemistry. Aldehyde and keto structures are “hot spots” along the cellulose chain, where further chain cleavage might occur. Carbonyls are also relevant for processes such as yellowing or aging. Conventional approaches (copper number, oxime or cya...

Pulp capping is a procedure that comprises adequate protection of the pulp tissue exposed to the oral environment, aiming at the preservation of its vitality and functions. This study evaluated the response of the dental pulps of dog teeth to capping with mineral trioxide aggregate (MTA) or calcium hydroxide P.A. For that purpose, 37 teeth were divided into two groups, according to the capping ...

Cellulose acetate fibers are commonly made by a dry-spinning process, in which cellulose acetate is firstly dissolved in acetone and then the cellulose acetate acetone solution is extruded through spinneret orifices that have extremely small diameters. Any insoluble substances in acetone solutions could cause disruptions in fiber extrusion, and are not tolerated. In this work, acetone-insoluble...