Beating of hemp bast fibres: an examination of a hydro-mechanical treatment on chemical, structural, and nanomechanical property evolutions

In this study, a gradually increased hydro-mechanical treatments duration were applied to native hemp bast fibres with a traditional pulp and paper beating device (laboratory Valley beater). There is often a trade-off between the treatment applied to the fibres and the effect on their integrity. The multimodal analysis provided an understanding of the beating impact on the fibres at multiple scales and the experimental design made it possible to distinguish the effects of hydro- and hydro-mechanical treatment. Porosity analyses showed that beating treatment doubled the macroporosity and possibly reduced nanoporosity between the cellulose microfibrils. The beating irregularly extracted the amorphous components known to be preferentially located in the middle lamellae and the primary cell walls rather than in the secondary walls, the overall increasing the crystallinity of cellulose from 49.3 % to 59.1 %, but a non-significant change in the indentation moduli of the cell wall was observed. In addition, beating treatments with two distinct mechanical severities showed a disorganization of the cellulose conformation, which significant dropped the indention moduli by 11.2 GPa and 8.4 GPa for 10 and 20 minutes of Valley beater hydro-mechanical treatment, respectively, compared to hydro-treated hemp fibres (16.6 GPa). Pearson’s correlation coefficients between physicochemical features and the final indentation moduli were calculated. Strong positive correlations were highlighted between the cellulose crystallinity and rhamnose, galactose and mannose as non-cellulosic polysaccharide components of the cell wall

Infants reduce their movements when their partner sings

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Transmission x-ray diffraction of undisturbed soil microfabrics obtained by microdrilling in thin sections

Clay mineralogical studies by X-ray diffraction performed on extracted <2-μm fractions do not always represent all clay mineral constituents present in the soil. In this work, transmission X-ray diffraction (TXRD) was applied to undisturbed microsamples of optically homogeneous mineral soil fabrics and features. These microsamples were isolated by microdrilling their periphery in soil thin sections, then removing them, and transferring them to glass capillaries for TXRD analysis. The usefulness of this technique for supplying in situ mineralogical information on identification, structure, and natural orientation of soil constituents was tested on mineral microfabrics and features of primary and secondary phyllosilicates. The study demonstrated that TXRD allowed detailed, representative interpretations of undisturbed mineral features and fabrics. In particular, this technique allowed us (1) to compare mineralogical compositions at selected microlocalities, (2) to study natural preferred orientations, and (3) to detect small amounts of minor mineral interstratification phases. In addition, complementary information on crystallography and crystal chemistry may be obtained by performing analytical transmission electron microscopy on the same microsample. | Clay mineralogical studies by X-ray diffraction performed on extracted <2-μm fractions do not always represent all clay mineral constituents present in the soil. In this work, transmission X-ray diffraction (TXRD) was applied to undisturbed microsamples of optically homogeneous mineral soil fabrics and features. These microsamples were isolated by microdrilling their periphery in soil thin sections, then removing them, and transferring them to glass capillaries for TXRD analysis. The usefulness of this technique for supplying in situ mineralogical information on identification, structure, and natural orientation of soil constituents was tested on mineral microfabrics and features of primary and secondary phyllosilicates. The study demonstrated that TXRD allowed detailed, representative interpretations of undisturbed mineral features and fabrics. In particular, this technique allowed us (1) to compared mineralogical compositions at selected microlocalities, (2) to study natural preferred orientations, and (3) to detect small amounts of minor mineral interstratification phases. In addition, complementary information on crystallography and crystal chemistry may be obtained by performing analytical transmission electron microscopy on the same microsample

Transmission x-ray diffraction of undisturbed soil microfabrics obtained by microdrilling in thin sections

Clay mineralogical studies by X-ray diffraction performed on extracted <2-μm fractions do not always represent all clay mineral constituents present in the soil. In this work, transmission X-ray diffraction (TXRD) was applied to undisturbed microsamples of optically homogeneous mineral soil fabrics and features. These microsamples were isolated by microdrilling their periphery in soil thin sections, then removing them, and transferring them to glass capillaries for TXRD analysis. The usefulness of this technique for supplying in situ mineralogical information on identification, structure, and natural orientation of soil constituents was tested on mineral microfabrics and features of primary and secondary phyllosilicates. The study demonstrated that TXRD allowed detailed, representative interpretations of undisturbed mineral features and fabrics. In particular, this technique allowed us (1) to compare mineralogical compositions at selected microlocalities, (2) to study natural preferred orientations, and (3) to detect small amounts of minor mineral interstratification phases. In addition, complementary information on crystallography and crystal chemistry may be obtained by performing analytical transmission electron microscopy on the same microsample. | Clay mineralogical studies by X-ray diffraction performed on extracted <2-μm fractions do not always represent all clay mineral constituents present in the soil. In this work, transmission X-ray diffraction (TXRD) was applied to undisturbed microsamples of optically homogeneous mineral soil fabrics and features. These microsamples were isolated by microdrilling their periphery in soil thin sections, then removing them, and transferring them to glass capillaries for TXRD analysis. The usefulness of this technique for supplying in situ mineralogical information on identification, structure, and natural orientation of soil constituents was tested on mineral microfabrics and features of primary and secondary phyllosilicates. The study demonstrated that TXRD allowed detailed, representative interpretations of undisturbed mineral features and fabrics. In particular, this technique allowed us (1) to compared mineralogical compositions at selected microlocalities, (2) to study natural preferred orientations, and (3) to detect small amounts of minor mineral interstratification phases. In addition, complementary information on crystallography and crystal chemistry may be obtained by performing analytical transmission electron microscopy on the same microsample