The use of the structure crystallinity index as a criterion for evaluating the concentration potential of quartz raw materials

Old manuscripts are among the most important elements of the cultural and historical heritage of ancient knowledge. Unfortunately, many of them suffer from degradation, mostly those written with iron gall inks. In the present work, a study using non-destructive techniques was designed with the aim of analyzing the elemental composition and structural characteristics of iron gall inks, reproduced in laboratory, paper and their interaction when the ink is deposited on paper, inducing the paper degradation. Proton induced X-ray emission, X-ray diffraction and Fourier-transform infrared spectroscopy provided the elemental and structural information, and photography under infrared (IR) and ultraviolet (UV) light allowed the differentiation between manufactured inks. Results show that the first step of inked paper deterioration is due to acid-hydrolysis of the cellulose and the presence of reactive Fe(II) species by reducing the crystallinity index of the paper, which is affected depending on the ink recipe and the starting raw materials. These results will be useful to future studies on ancient documents written with iron gall inks, which suffer deterioration due to ink corrosion, and to differentiate between the different paper degradation mechanisms.

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Formaldehyde-Free Wood Composite Fabricated Using Oil Palm Starch Modified with Glutardialdehyde as the Binder

International Journal of Chemical Engineering ◽

10.1155/2019/5357890 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Mohd Hazim Mohamad Amini ◽

Rokiah Hashim ◽

Nurul Syuhada Sulaiman

Keyword(s):

Oil Palm ◽

Raw Materials ◽

Starch Content ◽

Crystallinity Index ◽

Maximum Modulus ◽

Modulus Of Rupture ◽

Density Level ◽

Wood Composite ◽

Wood Composites ◽

Oil Palm Trunk

Oil palm trunk is a kind of biomass rich in starch content. Oil palm trunk waste was available throughout the year in Malaysia and Indonesia due to continuous felling of nonproductive, over 25-year-old trees. Even though some manufacturers were using it in plywood and veneer production, they are hard to handle which later becomes less favorable raw materials due to a high moisture content where combination with a high starch content quickly attracts fungus and wood-decaying agents. The objective of this work was to evaluate properties of experimental wood composite panels, manufactured using oil palm-extracted starch modified with glutardialdehyde (OPSMG) as a binder. Different analyses were employed to characterize the properties of the samples besides evaluation of bending, internal bonding strength, and dimensional stability of the panels. Characterization on the functional group using the FT-IR analysis showed presence of aldehyde groups and ketone stretching vibrations at 1736.05 cm−1 and 1596.25 cm−1, which proves the presence of glutardialdehyde besides formation of bonding between the OPSMG and the woody materials. The XRD analysis showed the starch modification had lowered the crystallinity index which in turn increased the strength of the manufactured wood composites. The OPSMG wood composites were also found to have lower thermal stability, as evaluated using the TGA analysis. It was recorded that the maximum modulus of rupture for OPSMG wood composites was achieved at the 0.80 g/cm3 density level with an average value of 15.446 N/mm2 which showed 38.00% increment in strength between those two types of wood composites. Thickness swelling after immersion in water can still be improved by incorporating the moisture-repellent material later. After analyzing the results, it was concluded that modified oil palm starch has the potential to be used as an environment friendly binder for wood composite making.

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PREPARATION OF NANOCELLULOSE FROM NON-WOOD PLANT RAW MATERIALS

chemistry of plant raw material ◽

10.14258/jcprm.2019035105 ◽

2019 ◽

pp. 15-21

Author(s):

Kseniya Sergeyevna Momziakova ◽

Timur Rustamovich Deberdeev ◽

Maksim Sergeyevich Vershinin ◽

Vladimir Viktorovich Leksin ◽

Aleksandr Aleksandrovich Momziakov ◽

...

Keyword(s):

Structural Modification ◽

Raw Materials ◽

Crystallinity Index ◽

Subsequent Treatment ◽

Degree Of Polymerization ◽

Degree Of Crystallinity ◽

X Ray ◽

Plant Raw Materials ◽

Transmission Electron ◽

Effective Use

The purpose of this work was to study the possibility of obtaining nanocellulose (NC) by ultrasonic (US) processing in the medium of liquid nitrogen (LN) powdered cellulose. To achieve this goal, it was necessary to determine the effect of the time of ultrasonic treatment in the medium of LN on the dispersed composition, crystallinity index and degree of polymerization (DP) of cellulose samples. Studies were performed using a powder X-ray diffractometer, a laser particle analyzer, and a scanning and transmission electron microscope. DP of cellulose was determined by the viscosity of its solution in cadoxene by the standard method. It has been found that cryogenic grinding of flax cellulose samples does not lead to significant changes in its structural modification and degree of crystallinity, which indicates the high resistance of this material to such effects. However, ultrasonic exposure in the medium of LN with the subsequent treatment with 25%, 45%, 65% H2SO4 allows to obtain cellulose nanospheres with a diameter of 48 to 437 nm and a yield of up to 40%. Unlike other types of nanoparticles (nanofibrillary, nanocrystalline cellulose), cellulose nanospheres have a larger surface area, which opens up the possibility of their effective use for the modification of composite materials.

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Effect of Ionic Liquids/water Pre-Treatment of Luffa ﬁbres on the Structural Properties

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.610-613.3587 ◽

2012 ◽

Vol 610-613 ◽

pp. 3587-3590

Author(s):

Li Wei ◽

Xiao Qing Shi ◽

Ying Wang ◽

Ying Chong Ma ◽

Ji Xiang Zhao ◽

...

Keyword(s):

Ionic Liquids ◽

Interfacial Adhesion ◽

Raw Materials ◽

Crystallinity Index ◽

Xrd Analysis ◽

Raw Material ◽

Water Mixture ◽

X Ray Diffraction ◽

X Ray ◽

Pre Treatment

Recently, the use of lignocellulosic ﬁbres to reinforcing composite has received an increased attention. However, lack of good interfacial adhesion makes important the treatment of raw materials. In this study, the raw material Luffa ﬁbres were treated by ionic liquids/water mixture and this treatment proved to be useful by elimination of gummy and waxy substances. The effect of the treatments on the structure of ﬁbres was showed using SEM and XRD (X-Ray Diffraction) analysis. The SEM results revealed that the treatment resulted in a removal of lignin, pectin and hemicellulose substances, and change the characteristics of the surface topography. The XRD analysis shows the increase of crystallinity index.

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Microstructural characterization of laser-melted/roller-quenched dicalcium silicate

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104972 ◽

1988 ◽

Vol 46 ◽

pp. 582-583

Author(s):

C. J. Chan ◽

K. R. Venkatachari ◽

W. M. Kriven ◽

J. F. Young

Keyword(s):

Particle Size ◽

Raw Materials ◽

Shape Change ◽

Microstructural Characterization ◽

Particle Size Effect ◽

Dicalcium Silicate ◽

Laser Melting ◽

Uniform Size ◽

Cell Shape Change ◽

Wide Range

Dicalcium silicate (Ca2SiO4) is a major component of Portland cement. It has also been investigated as a potential transformation toughener alternative to zirconia. It has five polymorphs: α, α'H, α'L, β and γ. Of interest is the β-to-γ transformation on cooling at about 490°C. This transformation, accompanied by a 12% volume increase and a 4.6° unit cell shape change, is analogous to the tetragonal-to-monoclinic transformation in zirconia. Due to the processing methods used, previous studies into the particle size effect were limited by a wide range of particle size distribution. In an attempt to obtain a more uniform size, a fast quench rate involving a laser-melting/roller-quenching technique was investigated.The laser-melting/roller-quenching experiment used precompacted bars of stoichiometric γ-Ca2SiO4 powder, which were synthesized from AR grade CaCO3 and SiO2xH2O. The raw materials were mixed by conventional ceramic processing techniques, and sintered at 1450°C. The dusted γ-Ca2SiO4 powder was uniaxially pressed into 0.4 cm x 0.4 cm x 4 cm bars under 34 MPa and cold isostatically pressed under 172 MPa. The γ-Ca2SiO4 bars were melted by a 10 KW-CO2 laser.

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Crystallization of barium hexaferrite

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100122216 ◽

1992 ◽

Vol 50 (1) ◽

pp. 362-363

Author(s):

Chung-kook Lee ◽

Yolande Berta ◽

Robert F. Speyer

Keyword(s):

Size Distribution ◽

Raw Materials ◽

Barium Hexaferrite ◽

Recording Media ◽

Magnetic Recording Media ◽

Promising Candidate ◽

Crystallization Method ◽

Temperature Heat ◽

High Density Magnetic Recording ◽

Temperature Heat Treatment

Barium hexaferrite (BaFe12O19) is a promising candidate for high density magnetic recording media due to its superior magnetic properties. For particulate recording media, nano-sized single crystalline powders with a narrow size distribution are a primary application requirement. The glass-crystallization method is preferred because of the controllability of crystallization kinetics, hence, particle size and size distribution. A disadvantage of this method is the need to melt raw materials at high temperatures with non-reactive crucibles, e.g. platinum. However, in this work, we have shown that crystal growth of barium hexaferrite occurred during low temperature heat treatment of raw batches.

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