scholarly journals Study on the Evaluation of Thermal Damage According to the Manufacturing Conditions of Korean Paper

2021 ◽  
Vol 37 (6) ◽  
pp. 648-658
Author(s):  
Ji Won Kim ◽  
Se Rin Park ◽  
Ki Ok Han ◽  
Seon Hwa Jeong

In this study, we aimed to analyze the chemical changes that occur in Korean paper in an accelerated deterioration environment of 105℃. We selected the Korean paper produced with different types of cooking agents (plant lye, Na2CO3) and during different manufacturing seasons (winter, summer). The degree of deterioration of the Korean paper was confirmed by measuring the brightness, yellowness, and pH level, and the degree of change in each vibrational region of cellulose as deterioration progressed through infrared (FT-IR) spectroscopy. The FT-IR analysis showed that, as deterioration progressed, the absorbance of the amorphous region in cellulose decreased, whereas the absorbance of the crystalline region slightly increased. X-Ray diffraction (XRD) analysis and Raman spectroscopy were performed to verify the changes in the crystalline and amorphous regions in cellulose indicated by the FT-IR results. Furthermore, the crystallinity index (CI) was calculated; it showed a slight increase after deterioration; therefore, CI was confirmed to follow the same trend as that observed for absorbance in the FT-IR results. In addition, as a result of Raman spectroscopic analysis, the degree of decomposition of the amorphous region in the cellulose under the manufacturing conditions was confirmed by the fluorescence measured after the deterioration.

2020 ◽  
Vol 45 (4) ◽  
Author(s):  
A. U. Barambu ◽  
D. E. A. Boryo ◽  
H. M Adamu ◽  
K. M Yahuza ◽  
A. Abdulkadir

In this research, a structural modification for a cellulose/polyester blend has been carried out using NH4OH, (NH4)2C2O4 and liquid NH3 which are environmentally friendly alternative scouring agents with NaOH as control. The scouring process was carried out on the samples with these alternative agents. Investigation into structural modification of cellulose/polyester blend fabric using NH4OH, (NH4)2C2O4 and liquid NH3 and its structural characterization with X-ray diffraction was carried. The results showed the inferences variation in the crystallinity index of scoured samples from (3.21-65.30%), the crystallite size of scoured samples (1.9-15 nm) in the crystalline region and (7-20 nm) in the amorphous region, inter-planar spacing of the scoured samples (0.340-0.350 nm) of the crystalline region and (0.350-0.340 nm) of the amorphous region and number of crystalline planes of the scoured samples is (3-11) of the cellulose/polyester blend fabric samples via X-ray diffraction studies. Among these alternative agents (NH4)2C2O4 and NH4OH showed better interaction with both amorphous and crystalline regions of the cellulose/polyester blend fabric samples without loss in crystallinity when used as scouring agents, and the possibilities of being a superior alternative with significant effect on the structures of the cellulose/polyester blend, while the other samples showed possibilities of being highly competitive with the conventional agent.


BioResources ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. 1980-1987
Author(s):  
Shujie Wang ◽  
Jin Sun ◽  
Mengjie Chen ◽  
Xianfeng Hou ◽  
Zhenzhong Gao

The Fenton reaction has been widely used in the pretreatment of lignocellulose. It offers the advantages of simple operation, fast reaction speed, and low pollution. In this study, the effects of different proportions of Fenton reagents on the enzymatic hydrolysis of poplar were compared and analyzed, and the optimal ratio of Fenton reagents was obtained. The maximum yield of enzymatic hydrolysis of glucose in Fenton pretreatment samples was 406 mg/g at H2O2 and Fe2+ concentrations of 1.0 mol/L and 0.01 mol/L, respectively, which was 2.5 times that of untreated samples. Meanwhile, the composition analysis and FT-IR analysis showed that Fenton pretreatment could degrade lignin and hemicellulose effectively. X-ray diffraction (XRD) analysis showed that Fenton pretreatment can partially destroy the amorphous region of poplar. These findings will contribute to efforts to improve the viability of the Fenton pretreatment process for converting biomass into energy.


2013 ◽  
Vol 331 ◽  
pp. 448-451
Author(s):  
De Lin Sun ◽  
Xian Chun Yu

Discarded wood was liquefied with phenol to prepare the liquefication basic woodceramics (LBW). The effects of sintering temperature on the phase changes had discussed. The Fourier transform infrared (FT-IR) analysis showed that, as sintering temperature rose, the elements of H and O were excluded gradually, as well the circle C-C structure had formed. The X-ray diffraction (XRD) analysis indicated that higher sintering temperature could improve the microcrystal structure. With the temperature increasing, (002) diffraction peak became strong and the diffraction angle 2θbecame larger, meanwhile, the stacking height of larger plane and the crystallite size increased also. In addition, the distances of interlamination drop drown, and the rank of microcrystal became more regulation and order. Butgvalues which character the degree of graphitization always were less than zero, and the integrated graphite structure had not found, suggesting the LBW was a kind of a difficult graphitization material.


2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Hao Ding ◽  
Yuebo Wang ◽  
Yu Liang ◽  
Faxiang Qin

Intercalated sericite was prepared by intercalation of cetyl trimethylammonium bromide (CTAB) into activated sericite through ion exchange with the following two steps: the activation of sericite by thermal modification, acid activation and sodium modification; the ion exchange intercalation of CTA+into activated sericite. Effects of reaction time, reaction temperature, CTAB quantity, kinds of medium, and aqueous pH on the intercalation of activated sericite were examined by X-ray diffraction (XRD) analysis, Fourier transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The results indicated that the CTA+entered sericite interlayers and anchored in the aluminosilicate interlayers through strong electrostatic attraction. The arrangement of CTA+in sericite interlayers was that alkyl chain of CTA+mainly tilted at an angle about 60° (paraffin-type bilayer) and 38° (paraffin-type monolayer) with aluminosilicate layers. The largest interlayer space was enlarged from 0.9 nm to 5.2 nm. The intercalated sericite could be used as an excellent layer silicate to prepare clay-polymer nanocomposites.


2021 ◽  
Vol 21 (4) ◽  
pp. 2212-2220
Author(s):  
T. S. Gokul Raja ◽  
S. Balamurugan ◽  
A. Reshma

In this work, several attempts were made to prepare nanoceramic zirconate (Nd2Zr2O7) powder for pigment applications. The single pyrochlore phase, Nd2Zr2O7 was successfully synthesized with the aid of flux at relatively low temperature (1000 °C) upon milling the reaction mixture made from Nd2O3 and ZrO2 in a tungsten carbide vial. Several characterizations were done on the thermal analysis (TG/DTA), X-ray diffraction (XRD), High-resolution scanning electron microscope (HRSEM), energy dispersive X-ray (EDX) analysis, Fourier-transform infrared (FT-IR) analysis, and near-infrared (NIR spectroscopy). A single-phase nanocrystalline (˜28 nm) pyrochlore structure (Fd3m) was confirmed through XRD analysis. A highly uniform particle in the size of ˜110 nm was observed for the Nd2Zr2O7 phase in the microimages. The vibrational (FT-IR) peaks at 423 cm-1 and 510 cm-1 in FTIR spectroscopic study confirmed the formation of pyrochlore structure. Higher NIR reflectivity recorded for this material in the 750–2500 nm region shows its novel application in color cool pigments for energy-saving paints reminiscent of Bi2−xYxCe2O7, Bi2Ce2−xTbxO7, and Gd2Ti2O7.


Author(s):  
Muhammad Wasim ◽  
Rameez Saeed Malik ◽  
Muhammad Usman Tufail ◽  
Ahsan Ullah Jutt ◽  
Rafiq Ahmad ◽  
...  

Hydroxyapatite was synthesized from bovine cortical bone by thermal decomposition method. The chemically cleaned bone was heated to 160 °C for 48 hour to remove moisture and any organic contents followed by decomposition in muffle furnace at 850 °C for 6 hours. The so-obtained white powder was characterized by Fourier Transform Infrared (FT-IR) spectroscopy and X-Ray Diffraction (XRD), SEM and EDX method. The FT-IR results proved the existence of hydroxyl (OH-) and phosphate (PO4-3) groups in the powder. XRD analysis was in support to the FT-IR spectrum, however, an additional phase of tri-calcium phosphate (TCP) was also observed as an impurity, SEM shows the surface morphology & EDX gives the Calcium (Ca) to Phosphorous (P) ratio. Key Words: Hydroxyapatite; Thermal Decomposition, Calcination


2020 ◽  
Vol 24 (7) ◽  
pp. 1175-1179
Author(s):  
A.U. Barambu ◽  
D.E.A. Boryo ◽  
H.M. Adamu ◽  
N.M. Lawal ◽  
A.B. Mustapha

This study investigated the effect of organic alternative scouring agents on structure of cotton/polyester blend fabric. A structural modification for a cellulose/polyester blend has been carried out using (COOH)2, CH3COOH and CH3CH2OH alternative scouring agents and NaOH was used as control. The scoured fabrics were then subjected to structural analysis using X-ray diffraction in order to expose the possible modifications on the pretreated fabrics. The samples showed possibilities of being highly competitive with the conventional agent. These inferences were drawn from the difference in the crystallinity index of scoured samples (10.10-60.03%), the crystallite size of scoured samples (6-9 nm) in the crystalline region (6-11 nm), in the amorphous region, inter-planar spacing of the scoured samples (0.340-0.350 nm) of the crystalline region and (0.360-0.390 nm) of the amorphous region of sample and number of crystalline planes of the scoured sample is (3-10) of the cellulose/polyester blend fabric samples via X-ray diffraction studies. Keywords; Cellulose, Fabric, Organic, Polyester, Scouring Agents


Author(s):  
Erdoğan Karip ◽  
Mehtap Muratoğlu

People are exposed to different kinds of diseases or various accidents in life. Hydroxyapatite (HA) has been widely employed for bone treatment applications. In this study, HA was extracted from sheep bones. Bio-composites were doped with 1, 5, and 10 wt.% of expanded perlite and 5 wt.% of ZrO2–MgO-P2O5. The bio-composites were prepared by the cold isostatic pressing method (250 MPa) and sintered at 900°C for 1 h. In order to evaluate the characteristics of the bio-composites, microhardness, density, X-ray diffraction (XRD), Fourier transform infra-red spectroscopy (FT-IR), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) analyses were carried out on them. Additionally, the specimens whose characteristics were determined were kept in synthetic body fluid (SBF), and their in vitro behavior was examined. As a result, it was observed that microhardness increased as both the weight and the grain size of the expanded perlite were increased. Calcium silicate, tri-calcium phosphate, and hydroxyapatite were observed in the XRD analysis of all samples, and the formation of apatite structures was increased by addition of ZrO2–MgO–P2O5.


Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1786
Author(s):  
Carla Queirós ◽  
Chen Sun ◽  
Ana M. G. Silva ◽  
Baltazar de Castro ◽  
Juan Cabanillas-Gonzalez ◽  
...  

The development of straightforward reproducible methods for the preparation of new photoluminescent coordination polymers (CPs) is an important goal in luminescence and chemical sensing fields. Isophthalic acid derivatives have been reported for a wide range of applications, and in addition to their relatively low cost, have encouraged its use in the preparation of novel lanthanide-based coordination polymers (LnCPs). Considering that the photoluminescent properties of these CPs are highly dependent on the existence of water molecules in the crystal structure, our research efforts are now focused on the preparation of CP with the lowest water content possible, while considering a green chemistry approach. One- and two-dimensional (1D and 2D) LnCPs were prepared from 5-aminoisophthalic acid and Sm3+/Tb3+ using hydrothermal and/or microwave-assisted synthesis. The unprecedented LnCPs were characterized by single-crystal X-ray diffraction (SCRXD), powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM), and their photoluminescence (PL) properties were studied in the solid state, at room temperature, using the CPs as powders and encapsulated in poly(methyl methacrylate (PMMA) films, envisaging the potential preparation of devices for sensing. The materials revealed interesting PL properties that depend on the dimensionality, metal ion, co-ligand used and water content.


2006 ◽  
Vol 118 ◽  
pp. 639-644
Author(s):  
Hye Sung Kim ◽  
Su Chak Ryu

Hydroxyapatite (Ca10(PO4)6(OH)2, HAp) powders is synthesized using the mixed powders of CaCO3 refined from oyster shells and phosphoric acid (H3PO4-98%, Daejung) as starting materials. The characteristic evaluation and chemical analysis of the synthesized powders is performed by X-ray diffraction (XRD), Fourier-transformed infra-red spectroscopy (FT-IR), and inductively-coupled plasma atomic emission spectroscopy (ICPAES). XRD analysis of synthetic powder by heat treatment at 1300°C for 2hrs shows only HAp peaks corresponding to stoichiometric HAp. It is confirmed by ICP-AES test that impurities such as Zn, In, Ti, Ba, Cd, Pb, and Mn, is not detected at all, but small amounts of Ti and Be is observed (0.099ppm Ti and 0.002ppm Ba). Variation of bone density is measured by giving medication of HAp powder with drinking water into human body continuously for three month. After the medication, the bone density is higher than the medication before. This means that HAp powder made from this process can be used as improver of bone density.


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