A parameter termed the crystallinity index (CI) has been used to describe the relative amount of crystalline material in cellulose. The traditional two-phase cellulose model describes cellulose chains as containing both crystalline (ordered) and amorphous (less ordered) regions [ 9 ]. See more This method, developed by Segal and coworkers [19], examined the changes in XRD spectra during decrystallization of cotton cellulose by … See more This method requires software to separate amorphous and crystalline contributions to the diffraction spectrum using a curve-fitting process. For the curve fitting, a few assumptions have to be made, such as the shape and … See more We have used solid-state 13C NMR to evaluate the CI of cellulose samples, employing the method of Newman [23]. In the NMR spectra in Figure 3, the peak at 89 ppm is assigned … See more The basis for this method was outlined by Ruland [29], who determined crystallinity by subtracting the amorphous contribution from diffraction spectra using an amorphous standard. … See more WebFeb 1, 2013 · The X-ray diffraction-based Segal Crystallinity Index (CI) was calculated for simulated different sizes of crystallites for cellulose Iβ and II. The Mercury software was used, and different crystallite sizes were based on different input peak widths at half of the maximum peak intensity (pwhm). The two cellulose polymorphs, Iβ and II, gave different …
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WebDefine crystalline. crystalline synonyms, crystalline pronunciation, crystalline translation, English dictionary definition of crystalline. adj. 1. Being, relating to, or composed of … WebBrowse by the journal of publication: Acta Crystallographica Section E. Inorganic Chemistry. Organometallics. Journal of the American Chemical Society. Dalton transactions (Cambridge, England : 2003) Acta Crystallographica Section C. Chemical Communications. CrystEngComm. mavis flex shopper
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WebCollect your sample’s diffraction pattern over the desired 2theta range. If your sample is semi-crystalline or fully amorphous, you’ll see a broad feature, as seen in this figure … WebApr 10, 2024 · Polytetrafluoroethylene (PTFE) is a semi-crystalline polymer offering many attractive properties. Its very low coefficient of friction, high thermal stability, good electrical insulation properties, hydrophobicity and biocompatibility make PTFE a material of wide usage in numerous industrial applications [1], [2], [3], [4], [5]. WebApr 23, 2024 · Crystalline index of cotton fibers A D8 Advanced X-ray diffractometer (Bruker, Germany) was applied to record the cotton fibers’ (H 2 O and D 2 O exchange treated) crystalline information. It was scanned in a 2θ range from 5° to 40° with a scan rate of 2°/min at 40 kV and 50 mA, respectively. hermanwhatever