The Effects of the Blending Condition on the Morphology, Crystallinity, and Thermal Stability of Cellulose Microfibers Obtained from Bagasse

In this study, cellulose microfibers were isolated from bagasse fibers in three stages. Initially, the fibers were treated with 5 wt.% NaOH solution followed by bleaching with 5 wt.% H2O2 in an alkali condition (pH 11) to remove hemicelluloses and lignin. Whole cellulosic fibers were obtained by mechanically separating the fibers using a modified kitchen blender to produce cellulose microfibers. Morphological (Scanning Electron Microscopy (SEM)) and structural analysis of the treated fiber was performed using Fourier Transformed Infrared (FTIR) spectroscopy and X-ray Diffraction (XRD). Morphological characterization identified that the diameter of the fibers varied between 20 nm to 20 µm and the FTIR analysis demonstrated that the treatments resulted in the gradual removal of lignin and hemicelluloses from the fiber. Furthermore, the XRD studies revealed that the combination of the chemical and mechanical treatment is an effective way to increase purity of cellulose (removal of amorphous lignin and hemicellulose) and break down the microfiber into shorter crystalline parts with higher crystallinity (77.25%) than raw bagasse (40.54%). Accordingly, changing the agitation time revealed that the cellulose crystallite size in the sample varied slightly with agitation time by using a blender (3.35 nm). Finally, the higher crystallinity and crystallite size improved the thermal stability of the cellulose microfiber confirming their suitability in the manufacturing biomaterial composites.

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The Hydro-Thermal Stability of Hornblende Syenite in NaOH Solution

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.633.230 ◽

2014 ◽

Vol 633 ◽

pp. 230-233

Author(s):

Cheng Zeng ◽

Jing Yang ◽

Hong Wen Ma ◽

Chang Jiang Liu

Keyword(s):

Thermal Stability ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Crystal Morphology ◽

X Ray Diffraction ◽

Solid Samples ◽

X Ray ◽

Naoh Solution ◽

Thermal Stability Of ◽

Scanning Electron

The microcline powder, which collected from the hornblende syenite from Anhui, China, was treated by NaOH solution at 250 °C for 2-6h. The solid samples were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The XRD shows that the main solid sample is hydroxycancrinite. The images observed by SEM indicate that the crystal morphology of the hydroxycancrinite can be presented as hexagonal cylindrical when it reacted with 4.17M NaOH at 250 °C for 6h.

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Effect of Acid/Fiber Ratio on Physical Properties of Cellulose Nanofibers Extracted from Cassava Pulp

Materials Science Forum ◽

10.4028/www.scientific.net/msf.890.103 ◽

2017 ◽

Vol 890 ◽

pp. 103-107

Author(s):

Thanh Chi Nguyen ◽

Ruksakulpiwat Chaiwat ◽

Yupaporn Ruksakulpiwat

Keyword(s):

Thermal Stability ◽

Physical Properties ◽

Acid Hydrolysis ◽

Cellulose Nanofibers ◽

X Ray Diffraction ◽

Cassava Pulp ◽

Transmission Electron ◽

Naoh Solution ◽

Bleaching Treatment ◽

Thermal Stability Of

Cellulose nanofibers (CeNF) were extracted successfully from cassava pulp (CP) by submitting to alkali, bleaching and acid hydrolysis treatments. The raw CP was mercerized with NaOH solution and then followed by bleaching treatment using a solution made up of equal parts (v:v) of acetate buffer and aqueous chlorite. In order to obtain cellulose nanofibers, the acid hydrolysis treatment of bleached fibers was performed using a mixture of HCl/H2SO4 (1:2 v/v). In this acid treatment reaction, the effects of acid/fiber ratio (ml/g) on physical properties of obtained cellulose nanofibers were investigated. Nanofibers were morphologically characterized by transmission electron microscopy (TEM) revealing the nanofibers with diameter in the range of 12-24 nm and immeasurable length were obtained. An increase in crystallinity of fibers after treatments was revealed by X-ray diffraction (XRD). Due to the introduction of sulfate groups at the outer surfaces of fibers during the hydrolysis, thermal stability of nanofibers, characterized by thermogravimetric analysis (TGA), was lower than that of raw CP. The acid/fiber ratio of 150ml/2g was found to be a proper ratio for thermal stability of obtained nanofibers. The crystallinity of nanofibers increased with the increase of acid/fiber ratio.

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Strontium Hydroxyapatite Synthesis, Characterization and Cell Cytotoxicity

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.160-162.117 ◽

2010 ◽

Vol 160-162 ◽

pp. 117-122 ◽

Cited By ~ 2

Author(s):

Zhi Hong Li ◽

Ji Min Wu ◽

Shu Jie Huang ◽

J. Guan ◽

Xi Zheng Zhang

Keyword(s):

Thermal Stability ◽

Hydrothermal Method ◽

Bone Repair ◽

X Ray Diffraction ◽

X Ray ◽

Strontium Hydroxyapatite ◽

Transmission Electron ◽

20 Nm ◽

Thermal Stability Of ◽

Phase Chemical

Strontium hydroxyapatite powders was prepared by the hydrothermal method using Sr(NO3)2 and (NH4)2HPO4 as reagents. Fourier transform infrared spectroscopy, X-ray diffraction, Transmission electron microscope, Energy dispersive X-ray, and Thermogravimetric-differential thermal analysis were employed to investigate the crystalline phase, chemical composition, morphology, and thermal stability of the Strontium hydroxyapatite. And the cytotoxicity of Strontium hydroxyapatite was analyzed through MTT assay. Results showed that Strontium hydroxyapatite prepared by hydrothermal Method has excellent crystal structure, good dispersion, high purity, and rod-like morphology with dimensions 200-500 nm in length and 20 nm in diameter. Meanwhile, the apatite has poor thermal stability. However, the apatite is cytocompatible and may have better biocompatibility, which can serve as strontium source incorporation into calcium phosphate cement and for bone repair.

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Formation and Thermal Stability of Nd0.32Y0.68Si1.7 Layers Formed by Channeled Ion Beam Synthesis

MRS Proceedings ◽

10.1557/proc-514-191 ◽

1998 ◽

Vol 514 ◽

Cited By ~ 1

Author(s):

M. F. Wu ◽

A. Vantomne ◽

S. Hogg ◽

H. Pattyn ◽

G. Langouche ◽

...

Keyword(s):

Thermal Stability ◽

Ion Beam ◽

Hexagonal Structure ◽

Orthorhombic Structure ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Good Crystalline Quality ◽

Ion Beam Synthesis ◽

Thermal Stability Of

ABSTRACTThe Nd-disilicide, which exists only in a tetragonal or an orthorhombic structure, cannot be grown epitaxially on a Si(111) substrate. However, by adding Y and using channeled ion beam synthesis, hexagonal Nd0.32Y0.68Si1.7 epilayers with lattice constant of aepi = 0.3915 nm and cepi = 0.4152 nm and with good crystalline quality (χmin of Nd and Y is 3.5% and 4.3 % respectively) are formed in a Si(111) substrate. This shows that the addition of Y to the Nd-Si system forces the latter into a hexagonal structure. The epilayer is stable up to 950 °C; annealing at 1000 °C results in partial transformation into other phases. The formation, the structure and the thermal stability of this ternary silicide have been studied using Rutherford backscattering/channeling, x-ray diffraction and transmission electron microscopy.

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Effects of Current on Arc Fabrication of Cu Nanoparticles

Journal of Nanomaterials ◽

10.1155/2010/403197 ◽

2010 ◽

Vol 2010 ◽

pp. 1-5 ◽

Cited By ~ 12

Author(s):

M. Z. Kassaee ◽

F. Buazar ◽

E. Motamedi

Keyword(s):

Thermal Stability ◽

Distilled Water ◽

Face Centered Cubic ◽

Cu Nanoparticles ◽

Dta Analysis ◽

Face Centered ◽

Average Size ◽

20 Nm ◽

Thermal Stability Of ◽

Sem Analyses

Arc-fabricated copper nanoparticles (Cu Nps) size, morphology and the crystalline structure, as well as the yields of Nps appear sensitive to the applied currents (50–160 A) in distilled water. The results indicate that the sizes of Cu Nps are directly proportional to the currents employed. At 50 A, TEM, XRD, and SEM analyses show fabrication of relatively purest, the most dispersed, face-centered cubic (fcc) brown Cu Nps with rather smallest average size of 20 nm. At the same current, the TGA-DTA analysis reveals neither weight loss nor gain, indicating thermal stability of the fabricated Cu Nps.

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Study of Thermal Behaviour of EPDM/SBR Blends and Carbon Nanocoatings Deposited by Sputtering

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.875.116 ◽

2021 ◽

Vol 875 ◽

pp. 116-120

Author(s):

Muhammad Alamgir ◽

Faizan Ali Ghauri ◽

Waheed Qamar Khan ◽

Sajawal Rasheed ◽

Muhammad Sarfraz Nawaz ◽

...

Keyword(s):

Thermal Stability ◽

Weight Loss ◽

Thermogravimetric Analysis ◽

Thermal Behavior ◽

Thermal Behaviour ◽

X Ray Diffraction ◽

X Ray ◽

Thermal Stability Of

In this study, the effect of SBR concentration (10 Phr, 20 Phr & 30 Phr ) on the thermal behavior of EPDM/SBR blends was studied. Thermogravimetric analysis (TGA) was used to check weight loss of samples as function of temperature by heating upto 600°C. X-ray diffraction (XRD) was performed to determine quality and % crystallinity of the elastomer blends. It was seen that % crystallinity improved with an increase in the content of SBR in EPDM/SBR blends. TGA revealed that the thermal stability of EPDM/SBR blends has improved by 17% than neat EPDM. Carbon nano-coatings produced by sputtering have no beneficial influence on thermal behaviour of elastomers.

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Syntheses, Crystal Structures and Thermal Stability of Co(II) and Zn(II) Complexes with Ethyl Carbazate

Zeitschrift für Naturforschung B ◽

10.1515/znb-2005-0505 ◽

2005 ◽

Vol 60 (5) ◽

pp. 505-510 ◽

Cited By ~ 12

Author(s):

Tong-Lai Zhang ◽

Jiang-Chuang Song ◽

Jian-Guo Zhang ◽

Gui-Xia Ma ◽

Kai-Bei Yu

Keyword(s):

Thermal Stability ◽

Aqueous Solutions ◽

Diffraction Analysis ◽

Single Crystals ◽

Slow Evaporation ◽

X Ray Diffraction ◽

Element Analysis ◽

Thermal Stabilities ◽

X Ray ◽

Thermal Stability Of

Cobalt(II) and zinc(II) complexes of ethyl carbazate (ECZ), [Co(ECZ)3](NO3)2 and [Zn(ECZ)3] (NO3)2, were synthesized. Single crystals of these two compounds were grown from aqueous solutions using a slow evaporation method. Their structures have been determined by X-ray diffraction analysis. Both of them are monoclinic with space group P21/n. The complexes are further characterized by element analysis and IR measurements. Their thermal stabilities are studied by using TG-DTG, DSC techniques. When heated to 350 °C, only metal oxide was left for both complexes.

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Polystyrene/Montmorillonite Nanocomposites: Study of the Morphology and Effects of Sonication Time on Thermal Stability

Journal of Nanomaterials ◽

10.1155/2013/650725 ◽

2013 ◽

Vol 2013 ◽

pp. 1-12 ◽

Cited By ~ 20

Author(s):

Mashael Alshabanat ◽

Amal Al-Arrash ◽

Waffa Mekhamer

Keyword(s):

Electron Microscopy ◽

Thermal Stability ◽

Solution Method ◽

Sonication Time ◽

X Ray Diffraction ◽

Transmission Electron ◽

Polystyrene Matrix ◽

Before And After ◽

Silicate Layers ◽

Thermal Stability Of

Polymer nanocomposites of polystyrene matrix containing 10% wt of organo-montmorillonite (organo-MMT) were prepared using the solution method with sonication times of 0.5, 1, 1.5, and 2 hours. Cetyltrimethylammonium bromide (CTAB) is used to modify the montmorillonite clay after saturating its surface with Na+ions. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to characterize the montmorillonite before and after modification by CTAB. The prepared nanocomposites were characterized using the same analysis methods. These results confirm the intercalation of PS in the interlamellar spaces of organo-MMT with a very small quantity of exfoliation of the silicate layers within the PS matrix of all samples at all studied times of sonication. The thermal stability of the nanocomposites was measured using thermogravimetric analysis (TGA). The results show clear improvement, and the effects of sonication time are noted.

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Immobilization of hemoglobin on stable mesoporous multilamellar silica vesicles and their activity and stability

Journal of Materials Research ◽

10.1557/jmr.2005.0360 ◽

2005 ◽

Vol 20 (10) ◽

pp. 2682-2690 ◽

Cited By ~ 15

Author(s):

Yufang Zhu ◽

Weihua Shen ◽

Xiaoping Dong ◽

Jianlin Shi

Keyword(s):

Thermal Stability ◽

Pore Size ◽

X Ray Diffraction ◽

X Ray ◽

Practical Applications ◽

Silica Material ◽

Transmission Electron ◽

Mesoporous Support ◽

Adsorption Desorption ◽

Thermal Stability Of

A stable mesoporous multilamellar silica vesicle (MSV) was developed with a gallery pore size of about 14.0 nm. A simulative enzyme, hemoglobin (Hb), was immobilized on this newly developed MSV and a conventional mesoporous silica material SBA-15. The structures and the immobilization of Hb on the mesoporous supports were characterized with x-ray diffraction, transmission electron microscopy, N2 adsorption-desorption isotherms, Fourier transform infrared, ultraviolet-visible spectroscopy, and so forth. MSV is a promising support for immobilizing Hb due to its large pore size and high Hb immobilization capacity (up to 522 mg/g) compared to SBA-15 (236 mg/g). Less than 5% Hb was leached from Hb/MSV at pH 6.0. The activity study indicated that the immobilized Hb retained most peroxidase activity compared to free Hb. Thermal stability of the immobilized Hb was improved by the proctetive environment of MSV and SBA-15. Such an Hb-mesoporous support with high Hb immobilization capacity, high activity, and enhanced thermal stability will be attractive for practical applications.

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