Cellulose content

Fiber Cellulose content (wt%) Spiral angle (%) Cross-sectional area A X 10-2 ( 2) Cell length L (mm) L/D ratio (-)... 

At first glance, the HRC scheme appears simple the polymer is activated, dissolved, and then submitted to derivatization. hi a few cases, polymer activation and dissolution is achieved in a single step. This simplicity, however, is deceptive as can be deduced from the following experimental observations In many cases, provided that the ratio of derivatizing agent/AGU employed is stoichiometric, the targeted DS is not achieved the reaction conditions required (especially reaction temperature and time) depend on the structural characteristics of cellulose, especially its DP, purity (in terms of a-cellulose content), and Ic. Therefore, it is relevant to discuss the above-mentioned steps separately in order to understand their relative importance to ester formation, as well as the reasons for dependence of reaction conditions on cellulose structural features. 

The determination of the sugar composition was performed with and without prehydrolysis to determine the cellulose content. Cellulose was present in soy meal and in WUS, the content was respectively 17.2 and 17.9 mol%. Both soy meal and WUS contained mainly galactose, glucose (cellulose), arabinose and uronic acids and their sugar compositions were very similar. This indicates that no sugar residues were specifically removed during the isolation procedure. 

Pulp type is also important and, in general, unbleached pulps are easier to size than bleached pulps. Pulps with a high cellulose content are extremely difficult to size and require as much as 10 times the amount of reacted AKD to produce similar levels of sizing to those of Kraft pulps. This effect is not easily understood and cannot be explained in terms of surface area. The presence of fillers also increases the amount of size required, and sizing efficiency has... 

Fignre 6.20 shows the plots for yields of hydrogen from snpercritical water extraction of shell samples versns cellulose content at different temperatures. The yields of hydrogen from supercritical water extraction increase with increasing cel-Ixflose contents of the shell samples (Demirbas, 2004). 

Fig. 6.20 Plots for yields of hydrogen from supercritical water extraction of shell samples versus cellulose content at different temperatures...

Figures 1 and 2 show positive correlation, although of varying degrees of goodness of fit, between the specific activities of endo ucanase, exoglucanase, and -glucosidase activities with the cellulose composition and degradation in digester feed, respectively. These data indicate a direct relationship between the cellulose content in the feed and cellulase enzyme complex production by the digester consortia. In this system, as in many others studied, cellulose is an effective inducer of cellulase secretion (67,68),...

The effects of feedstock cellulose content on cellulase enzyme activities in the digester system were examined in multiple laboratory-scale CSTR digesters operated under similar conditions with identical levels of feedstock organic loading (g VS/reactor d) but different levels of cellulose (Solka Floe). In general, all celli se enzyme... 

Figure 1. Comparison of the effects of feedstock cellulose content on specific ceUulase enzyme activities in sludge from 4 CSTR reactors operated under similar conditions. Although the cellulose content of the feedstock was varied, the total volatile solids content for all reactors was equivalent.

The fact that EMC reduction as a function of acetyl content is the same for many different llgnocelluloslc materials Indicates that reducing moisture sorption and, therefore, achieving cell wall stability are controlled by a common factor. The lignin, hemlcellulose, and cellulose contents of all the materials plotted in Figure 2 are different (Table II). Earlier results showed that the bonded acetate was mainly in the lignin and hemicelluloses (33) and that Isolated wood cellulose does not react with uncatalyzed acetic anhydride ( 4) ... 

It has little, if any, adverse effect on the lung, and there are no reports of organic disease or toxic effect. The health effects attributed to wood, cotton, flax, jute, and hemp are not attributable to their cellulose content but rather to the presence of other substances. 

L.) was also found, and was readily distinguishable by a brittleness of the culm which appeared only after maturity of the plant. This mutant had a lower cellulose content, and this difference was assumed to be related to the brittleness of the culm (24). Significant differences were also found in the extractability of the lignin fractions and associated phenolic acids (25-26), suggesting that lignin formation was also affected. 

Dissolution profiles from tablets containing 60% theophylline and 25% microcrystallme cellulose showed a smaller difference in the release rate of theophylline from heated and non-heated tablets (Fig. 3). Nevertheless, both of these tablets demonstrated a matrix-controlled release. These results suggest that the level of excipient in the tablet exerted a significant effect on the dissolution release properties of thermally and non-thermally treated tablets. As the microcrystalline cellulose content increased, the difference in release rates between heated and non-heated tablets became more pronounced. 

New International Dictionary, Merriam Co, Springfield, Mass(195I), 73 Alperox C. Trade name for tech lauroyl peroxide manufd by the Lucidol Division of Wallace Tieraan, Inc, Buffalo, NY Alpha-Cellulose is that portion of cellulosic materialfpulp, paper, etc) which,after treatment with 17,5% NaOH(mercerized strength) at 20° and diln to 7.3% NaOH,can be separated by filtration. The residue of alpha-cellulose is a good index of the undegraded cellulose content of the material. The alkali treatment removes degraded(oxidized or hydrolyzed) cellulose and short chain material. Some pentosans and hexosans may... 

Cross and Bevan [59] suggested defining the pure cellulose content of a commercial cellulose in terms of its behaviour in the presence of a 17-18% aqueous sodium hydroxide solution. That part of commercial cellulose which is insoluble in this solution bears the name of a-cellulose and is the true cellulose, ft- and y-cellulose remain dissolved in the caustic soda solution. The difference between... 

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