Fortisan, cellulose triacetate, and NOroxidized cellulose were pyrolyzed in a vacuum in the temperature range 1800 to 465 0 C. Cotton cellulose and cellulose t ri acetate were also pyrolyzed in nitrogen at atmospheric pressure. The tar yields were in the decreasing order from: Cotton, Fortisan, cellulose triacetate, and oxidized cellulose. The other volatiles consisted mainly of acetic acid, ca...

particularly eMcient. The cellulose productiyities of 412 isolates were estimated by cultuTing in two different media under both shaken and static conditions. No correlation between the amounts of cellulose accumulated in shaken and static cultures was observed. Higher cellulose accumlllation was obtained in the shaken cultures using a corn steep liquorlfructose-based medium than a conyentional...

Bacterial cellulose, an exopolysaccharide produced by some bacteria, has unique structural and mechanical properties and is highly pure as compared to plant cellulose. This article presents a critical review of the available information on the bacterial cellulose with special emphasis on its fermentative production and applications. Information on the biosynthetic pathway of bacterial cellulose...

Gluconacetobacter hansenii, a Gram-negative bacterium, produces and secrets highly crystalline cellulose into growth medium, and has long been used as a model system for studying cellulose synthesis in higher plants. Cellulose synthesis involves the formation of β-1,4 glucan chains via the polymerization of glucose units by a multi-enzyme cellulose synthase complex (CSC). These glucan chains as...

Plant cellulose has a hierarchical structure with hemicelluloses and lignin in cell walls, forming natural composites at the nanometer/micrometer levels. The smallest elements next to cellulose molecules are cellulose microfibrils ~3 nm and several microns in width and length, respectively (Fig. 1). Each cellulose microfibril consists of 30-40 fully extended cellulose chains, and forms crystall...

Microtubules determine the orientation of newly formed cellulose microfibrils in expanding cells. There are many hypotheses regarding how the information is transduced across the plasma membrane from microtubules to cellulose microfibrils. However, the molecular mechanisms underlying the co-alignment between microtubules and cellulose microfibrils were not revealed until the recent discovery of...

In order to evaluate the reliability of using repulped cellulose in transformers, the aging process was applied on standard and repulped cellulose in a laboratory accelerated model by increasing of temperature to 150 ° C and their behavior was monitored by measuring the amount of 2-furfural released in oil by HPLC (High Performance Liquid Chromatography) in the consecutive aging periods and...

Present paper examines the effect of acid type and hydrolysis conditions on morphology, size, yield and crystallinity of produced cellulose nanocrystal (CNC). Cellulose obtained from waste office paper was hydrolyzed under the same conditions by Maleic acid (MA) and Sulfuric Acid (SA) in separate treatments.  Also this cellulose was hydrolyzed under different timing and temperature by MA and SA...

Phase inversion cellulose acetate propionate membranes showed low permeability to hydrogen peroxide aqueous solutions. Their permeability was increased by alkaline hydrolysis of the ester linking units. However, the permeability remained lower than that of an unsubstituted cellulose membrane. The inclusion of hydroxypropyl cellulose in the membrane formulation, followed by an alkaline hydrolysi...

The large availability of cellulose in nature and the low cost of cellulose derivatives make the cellulosebased hydrogels particularly attractive. New hydrogels were obtained by chemical cross-linking of different cellulose allomorphs (cellulose I, cellulose II and cellulose III) and xanthan with epichlorohydrin. The preparation conditions of the transparent cellulose hydrogels were established...