Cladophora cellulose

Finally, the spectrum of the Cladophora cellulose which survived the strong acid hydrolysis closely resembled the cotton hydrocellulose spectrum except that the resolution was much better in the former spectrum. A contrast in resolution is consistent with a difference in the average lateral dimensions for the crystallites this difference is corroborated by electron microscopy. The close similarity of multiplet relative intensities in these two samples, in spite of their different crystallite surface-to-volume ratios verifies that surface resoncinces cire not determining the apparent multiplet intensities, particularly, for the 88-92 ppm region of the C l resonance. 

Figure 10. CP-MAS spectra of Cladophora cellulose as a function of the indicated delay times in a experiment. Total intensities are also given.

Figure 10 indicates that (a) If tvrc) allomorphs coexist in the Cladophora cellulose, the T behavior of both allomorphs is the same, (b) If the reduction of intensity in the T ... 

Finally, an attempt is made to Isolate the true and Ig spectra, based on the original and hydrolyzed samples of Cladophora cellulose. Whereas the spectrum is nearly identical to that originally proposed (1-3), the Ig spectrum is ambiguous and two possible spectra are proposed. 

Mihranyan, A., Nyholm, L., and Bennett, G. (2008). A novel high specific surface area conducting paper material composed of polypyrrole and Cladophora cellulose. I. Phvs. Chem. B. 112(39), 12249-12255. 

Razaq, A., Mihranyan, A., Welch, K., Nyholm, L., Strpmme, M. Influence of the type of oxidant on anion exchange properties of fibrous Cladophora cellulose/polypyrrole composites. J. Phys. Chem. B 113, 426—433 (2009)... 

The work conducted by Gustafsson et al. [19] evaluated the particle properties and solid-state characteristics of two different brands of microcrystalline cellulose (Avicel PH101 and a brand obtained from the alga Cladophora sp.) and related the compaction behavior to the properties of the tablets. The difference in fibril dimension and, thereby, the fibril surface area of the two celluloses were shown to be the primary factor in determining their properties and behavior. 

Figure 7 Alternative candidates for the spectra of l and 1 derived from linear combinations of the spectra of l

Mechanical beating of an algal cellulose from Cladophora glomerata was carried out for 5 hr in a Waring blender at 1% and 3% solids consistency. Beating was judged more efficient in the latter case based on a greater retention of water. 

Spectra of Several Native Celluloses. In Figure 3 the CP-MAS spectra of several higher plant celluloses are compared and are also contrasted to the spectrum of algal cellulose from Cladophora glomerata (bottom spectrum). In Figure 4, the spectra of two samples of bacterial cellulose from two different sources of Acetobacter xylinum, several algal celluloses, and the Cladophora, beaten at 1% solids consistency, are shown. 

Figure 6 shows spectra of five preparations of algal celluloses obtained from Cladophora spectrum A is from the original purified cellulose, spectrum B is that of the same cellulose beaten in a Waring Blender for 5 h while dispersed in water at 1 solids consistency, spectrum C is like B except that the beating was carried out at 3 solids consistency, spectrum D is that of the beaten cellulose in spectrum B following acid hydrolysis in 4N HCl for 44 h at 100 C (22 mass recovery), and... 

The first attempt to establish the crystal and molecular structure of CTA I was made by Stipanovic and Sarko, who suggested the occurrence of parallel-arranged cellulosic chains within an orthorhombic unit-cell. Later, the structural analysis of the diffraction pattern from an acetylated material derived from the green alga Cladophora sp. established it as a one-chain unit cell crystallizing in the P2i space group (fl = 5.94 A, = 11.43 A, c = 10.46 A, y = 95.4°, density = 1.375). 

Several types of algae like red, green, and yellow are known to produce cellulose in their cell waU. Some of the most commonly used algae species are Micrasterias denticulata, valonia, cladophora, boergesenia, etc. The difference in the biosynthesis process happens in different species cellulose microfibrils obtained may also differ from each other. Out of these different species, green algae are the most preferred species for cellulose extraction (Moon et al. 2011). 

Figure 1. CP/MAS C-NMR spectra recorded at 7.05 T on cellulose / isolated from different sources and one hr aft pulp. From bottom to top the sources are Valonia, Cladophora, Halocynthia, and cotton linters. The top spectrum is bleached birch krcft pulp that contains hemicelluloses. (Reproduced with permission from reference 16. Copyright 1999).

The main sources of cellulose are issued to i) primitive organisms like bacteria ( Acetobacter xylinum), algae (ex Valonia, Cladophora, Microdictyon) ii) plants (ex wood, cotton, flax, ramie, jute, parenchyma of sugar beet pulp...) and iii) envelop of sea animals belonging to the Ascidians family (ex tunicate). 

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