The Effect of Different Methods to Pretreat Reed Pulp on the Crystallinity of Microcrystalline Cellulose

2014 ◽  
Vol 1056 ◽  
pp. 12-15 ◽  
Author(s):  
Wen Long Zhang ◽  
Wen Long Zhao ◽  
Ya Jie Dai
Keyword(s):  
Crystallite Size ◽  
Microcrystalline Cellulose ◽  
Average Crystallite Size ◽  
Comprehensive Analysis ◽  
Raw Material ◽  
Type I ◽  
X Ray Diffraction ◽  
X Ray ◽  
Dimethyl Acetamide ◽  
Crystal Type

Reed Pulp was Raw Material that Pretreated by Four Methods {ultrasonic, Microwave, N, N-Dimethyl Acetamide (DMAc) and Tetrahydrofuran (THF)}. Reed Microcrystalline Cellulose (MCC) was Prepared by the Dilute Hydrochloric Acid Hydrolysis from Pretreated Reed Pulp. the Influences of Pretreatment Methods on Crystalline Type, Crystallinity and Crystallite Size of MCC were Investigated by X-Ray Diffraction (XRD). the Results Showed that the Crystallinity of MCC with Four Pretreatment Methods was 68.45%, 62.28%, 63.21% and 69.56%, Respectively. the Average Crystallite Size of MCC Prepared by Hydrolysis after Pretreated by Dmac was the Largest. whereas, the Crystal Type of MCC was Not Changed, it was still the Cellulose Type I. Comprehensive Analysis Indicated that the Effects of MCC Prepared by Hydrolysis after Pretreated by Ultrasonic were the Best.

Effect of reaction temperature on the average crystallite size of SexTe1−x alloys

1986 ◽  
Vol 1 (2) ◽  
pp. 234-236 ◽  
Author(s):  
Santokh S. Badesha ◽  
George T. Fekete ◽  
Ihor Tarnawskyj
Keyword(s):  
Crystallite Size ◽  
Small Particle ◽  
Chemical Method ◽  
Average Crystallite Size ◽  
Organic Media ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electrophotographic Properties ◽  
Dark Decay ◽  
Chalcogenide Materials

Electrophotographic properties of chalcogenide materials are readily influenced by altering their composition and/or structure. Dark decay and cycle down of photoreceptors utilizing small particle generators are both directly proportional to average crystallite size (ACS). This paper describes a novel chemical method to control the ACS of Se, Te, and Sex Te1−x alloys. These chalcogenide materials are prepared as powders by the reduction or coreduction of SeIV and/or TeIV intermediates with hydrazine, in organic media. To control the ACS of precipitated chalcogens the reaction is carried out at the desired temperature. X-ray diffraction measurements are used to determine the ACS, homogeneity, and phase of these precipitated powders.

X-ray diffraction Warren–Averbach mullite analysis in whiteware porcelains: influence of kaolin raw material

Clay Minerals ◽  
2018 ◽  
Vol 53 (3) ◽  
pp. 471-485 ◽  
Author(s):  
Angel Sanz ◽  
Joaquín Bastida ◽  
Angel Caballero ◽  
Marek Kojdecki
Keyword(s):  
Crystallite Size ◽  
Firing Temperature ◽  
Microstructural Analysis ◽  
Stoichiometric Composition ◽  
Raw Material ◽  
Size Distributions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Different Temperatures ◽  
Crystallite Sizes

ABSTRACTCompositional and microstructural analysis of mullites in porcelain whitewares obtained by the firing of two blends of identical triaxial composition using a kaolin B consisting of ‘higher-crystallinity’ kaolinite or a finer halloysitic kaolin M of lower crystal order was performed. No significant changes in the average Al2O3 contents (near the stoichiometric composition 3:2) of the mullites were observed. Fast and slow firing at the same temperature using B or M kaolin yielded different mullite contents. The Warren–Averbach method showed increase of the D110 mullite crystallite size and crystallite size distributions with small shifts to greater values with increasing firing temperature for the same type of firing (slow or fast) using the same kaolin, as well as significant differences between fast and slow firing of the same blend at different temperatures for each kaolin. The higher maximum frequency distribution of crystallite size observed at the same firing temperature using blends with M kaolin suggests a clearer crystallite growth of mullite in this blend. The agreement between thickening perpendicular to prism faces and mean crystallite sizes <D110> of mullite were not always observed because the direction perpendicular to 110 planes is not preferred for growth.

Corroboration of Structural Properties of Dy2O3-TiO2 Nanocomposites through X-Ray Diffraction and Raman Spectroscopy

2017 ◽  
Vol 17 ◽  
pp. 127-130
Author(s):  
J. Dhanalakshmi ◽  
D. Pathinettam Padiyan
Keyword(s):  
Raman Spectroscopy ◽  
Crystallite Size ◽  
Structural Properties ◽  
Oxygen Vacancies ◽  
Raman Band ◽  
Anatase Phase ◽  
Average Crystallite Size ◽  
X Ray Diffraction ◽  
X Ray ◽  
Weight Percentage

Dy2O3-TiO2 nanocomposites with different weight percentage (0, 2, 4, 8 & 10)Dy were synthesized bysol-gel method and named as 0DT, 2DT, 4DT, 6DT, 8DT and 10DT. The structural properties of these nanocomposites are characterized by X-ray diffraction (XRD) and Raman spectroscopy. XRD results show that Dy2O3-TiO2 nanocomposites have anatase phase with tetragonal structure. The average crystallite size of the Dy2O3-TiO2 nanocomposites lies between 10 to 18 nm.Coupling of Dy with TiO2 shifts the Raman band to higher wavenumber side indicating the creation of oxygen vacancies in the TiO2 lattice.

X-ray structure and microstructure determination of the mixed sesquioxides (Eu1−xYbx)2O3prepared by a sol–gel process

2003 ◽  
Vol 36 (6) ◽  
pp. 1411-1416 ◽  
Author(s):  
Z. K. Heiba ◽  
Y. Akin ◽  
W. Sigmund ◽  
Y. S. Hascicek
Keyword(s):  
Crystallite Size ◽  
Rietveld Method ◽  
Sol Gel ◽  
Average Crystallite Size ◽  
X Ray Diffraction ◽  
X Ray ◽  
Profile Fitting ◽  
Cationic Distribution ◽  
Sol Gel Process ◽  
Multiple Orders

Polycrystalline samples of (Eu1−xYbx)2O3(x= 0.0, 0.1, 0.2, 0.5, 0.8, 0.9 and 1.0) were synthesized by a sol–gel process. X-ray diffraction data were collected and the crystal structures were refined by the Rietveld method. All samples are found to have the same crystal system and formed solid solutions over the whole range ofx. The lattice parameters are found to vary linearly with the compositionx. The cationic distribution over the two non-equivalent sites 8band 24dof the space group Ia{\bar 3} is found to be random in the range 0.0 <x≤ 0.5 and preferential in the range 0.5 <x≤ 1.0. Replacing Eu3+and Yb3+by each other introduces slight changes in the atomic coordinates. Crystallite size and microstrain analysis are performed on single and multiple orders for each sample using profile fitting and the Warren–Averbach method. The obtained values of microstrain are correlated with the distribution of the rare earth (RE) ions over the two cationic sites of the structure. The average crystallite size ranges from 35 to 96 nm and the mean-square strain from 0.052 to 0.225 × 10−2.

scholarly journals Formation of NanoscaleMg(x)Fe(1-x)O  (x=0.1,0.2,0.4)Structure by Solution Combustion: Effect of Fuel to Oxidizer Ratio

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Mohsen Ahmadipour ◽  
K. Venkateswara Rao ◽  
V. Rajendar
Keyword(s):  
Particle Size ◽  
Electron Microscope ◽  
Crystallite Size ◽  
Average Crystallite Size ◽  
Combustion Method ◽  
X Ray Diffraction ◽  
Solution Combustion ◽  
X Ray ◽  
Particle Size And Morphology ◽  
Size And Morphology

Mg(x)Fe(1-x)O(magnesiowustite) nanopowder samples synthesized by solution-combustion method and fuel to oxidizer ratio (Ψ=1,1.25) are used as a control parameter to investigate how particle size and morphology vary withΨ. The method is inexpensive and efficient for synthesis of oxide nanoparticles. The average crystallite size ofMg(x)Fe(1-x)Onanoparticles was estimated from the full-width-half maximum of the X-ray diffraction peaks of powders using Debye-Scherrer’s formula; the average crystallite size varies from 16 nm to 51 nm. From X-ray diffraction analysis, it was observed thatMg(x)Fe(1-x)Onanoparticles have cubic structure. The particle size measured by particle size analyzer ranges from 37.7 nm to 73 nm which is in the order of XRD results. Thermal analysis was done by thermal gravimetric-differential thermal analyzer. The particle size and morphology of the synthesized powder were examined by transmission electron microscope and scanning electron microscope. The crystal size and particle size were compared with some of the most recently published research works by XRD and TEM. FTIR conforms formation of theMg(x)Fe(1-x)O.

scholarly journals Determination of the crystallite size and crystal structure of magnesium powder by x-ray diffraction

2020 ◽  
Vol 20 (3) ◽  
pp. 61-65
Author(s):  
ISMAIL ISMAIL ◽  
RESI MULIANI ◽  
ZULFALINA ZULFALINA ◽  
SITI HAJAR SHEIKH MD FADZULLAH
Keyword(s):  
Crystal Structure ◽  
Crystallite Size ◽  
Rietveld Method ◽  
Average Crystallite Size ◽  
Powder Sample ◽  
X Ray Diffraction ◽  
Magnesium Powder ◽  
X Ray ◽  
Lattice Constants ◽  
Packed Structure

Magnesium powder has become an important material in the development of science and technology such as alloy and hydrogen storage. In this work, the chemical composition, crystallite size, and crystal structure of the magnesium powder sample have been studied by using x-ray fluorescent and x-ray diffraction. The x-ray diffraction data of the magnesium powder sample was analyzed by using the Rietveld method to obtain the crystal structure. Our results show that the purity of our magnesium powder sample is 93.1%. Our sample has good crystallinity with the average crystallite size of 31 nm. The crystal structure is found to be a hexagonal closed-packed structure with the lattice constants of 3.2100 Å (a and b-axis) and 5.2107 Å (c-axis). Our result revealed that the lattice constant in the c-axis of magnesium powder is influenced by impurity. This finding suggests that the impurity can affect the crystal structure of a material in general.

scholarly journals Analysis of Crystallinity and Physical Properties of the Bio-solar Gemstone

2020 ◽  
Vol 8 (3) ◽  
pp. 151-160
Author(s):  
Ismail Ismail ◽  
Akmal NIzar ◽  
Murzal . ◽  
Zulkarnain Jalil
Keyword(s):  
Specific Gravity ◽  
Physical Properties ◽  
Crystallite Size ◽  
Average Crystallite Size ◽  
Crystalline Material ◽  
X Ray Diffraction ◽  
X Ray

Abstract – Bio-solar is one of the natural gemstones found in the province of Aceh in Indonesia. A recent study suggested that this gemstone could be considered as a vesuvianite type of gemstone. Nevertheless, detail information of this bio-solar gemstone is still unknown. We do not know whether the bio-solar gemstone is crystalline or amorphous. The specific gravity and the hardness of this gemstone are also still unknown. This information is essential to determine the quality of a gem. To answer those questions, we have used x-ray diffraction to study the bio-solar gemstone from the province of Aceh in Indonesia. The physical properties (specific gravity and hardness) of this gemstone have also been measured. We found that the bio-solar gemstone is composed by CaO, SiO2, MgO, Al2O3, Fe2O3, and TiO2 phases. Our results revealed that the bio-solar gem is a crystalline material, not amorphous. The average crystallite size of this gemstone is found to be 353 Å (35 nm). Moreover, the specific gravity of bio-solar gemstone is found to be 3.09 – 3.34. Its hardness is 3 to 4 mohs. Thus, the bio-solar is a good quality gemstone. Our finding confirmed that the bio-solar could be classified as a vesuvianite gemstone.

Structure Analysis of Nanocrystalline MgO Aerogel Prepared by Sol-Gel Method

2007 ◽  
Vol 130 ◽  
pp. 203-206 ◽  
Author(s):  
Grzegorz Dercz ◽  
Lucjan Pająk ◽  
Krystian Prusik ◽  
Roman Pielaszek ◽  
Janusz J. Malinowski ◽  
...  
Keyword(s):  
Crystallite Size ◽  
Magnesium Oxide ◽  
Sol Gel ◽  
Average Crystallite Size ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Gel Technique ◽  
Microscopy Images ◽  
Nanocrystalline Mgo

Wet gel obtained by sol-gel technique was dried in supercritical CO2 to prepare hydrated form of magnesium oxide. Calcination at 723 K under vacuum yielded nanocrystalline MgO aerogel. Structure studies were performed by X-ray diffraction, scanning and transmission electron microcopies. Electron microscopy images reveal rough, unfolded and ramified structure of solid skeleton. Specific surface area SBET was equal to 238 m2/g. X-ray pattern reveals the broadened diffraction lines of periclase, the only crystalline form of magnesium oxide. The gamma crystallite size distribution was determined using FW 5 4 / 5 1 M method proposed by R. Pielaszek. The obtained values of <R> and σ (measure of polydispersity) of particle size parameters are equal to 6.5 nm and 1.8 nm, respectively, whereas the average crystallite size estimated by Williamson-Hall procedure was equal to 6.0 nm. The obtained at Rietveld refinement Rwp, and S fitting parameters equal to 6.62% and 1.77, respectively, seem to be satisfactory due to the nanosize of MgO crystallites and because of the presence of amorphous phase.

scholarly journals Investigation of the nanocrytalline SnO2 Synthesized by Homogeneous Precipitation

2015 ◽  
Vol 12 (11) ◽  
pp. 3977-3988
Author(s):  
Mahmoud. N. Abdel-Salam ◽  
M. A. Abdel-Rahim ◽  
A. Gaber ◽  
A. Y. Abdel-Latief
Keyword(s):  
Crystallite Size ◽  
Surface Area ◽  
Tin Dioxide ◽  
Sno2 Nanoparticles ◽  
Average Crystallite Size ◽  
Nanocrystalline Powder ◽  
X Ray Diffraction ◽  
X Ray ◽  
Calcination Temperatures ◽  
Transmission Electron

Nanocrystalline tin dioxide synthesized by the homogeneous pre cipitation method using the reaction of tin tetrachloride pentahydrate and urea solutions has been investigated. The nanocrystalline powder has been traced at different calcination temperatures (300ºC-1050ºC), and then characterized by using   Thermogravemetric analysis, differential thermal analysis and x-ray diffraction. The microstructure of the obtained nanoparticles has been examined by scanning and transmission electron microscopy. The average crystallite size, determined by x-ray diffraction, was found to be in the range of 3 –30 nm. The analysis exhibited a tetragonal phase.  Optical properties were investigated by a UV–vis absorption spectrophotometer. The calculated optical band gap lies between 4.47–3.71 eV as a result of increasing the calcination temperatures and crystallite size. Surface area and porosity of SnO2 nanoparticles are measured. Specific surface area which is related to pore volume and decreases from 155 m2/g at 100ºC to 3.3 m2/g at 1050ºC. 

Crystallinity and Morphological of Cellulose Extraction from Elaeis guineensis Jacquin Frond

2015 ◽  
Vol 819 ◽  
pp. 251-255
Author(s):  
M. Muhammad Safwan ◽  
Hui Lin Ong ◽  
Hazizan Md Akil
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Field Emission ◽  
Microcrystalline Cellulose ◽  
Elaeis Guineensis ◽  
Raw Material ◽  
X Ray Diffraction ◽  
X Ray ◽  
Bleaching Treatment ◽  
Scanning Electron

The work described in this paper is the extraction of microcrystalline cellulose from Elaeis Guineensis Jacquin Frond using alkaline and bleaching treatment. Microcrystalline cellulose extracted has been characterized by X-Ray Diffraction (XRD) and Field Emission Scanning Electron Microscopy (FESEM). Morphological investigation of fibers was performed using field emission scanning electron microscopy (FESEM) where rod like fiber can be observed. Crystallinity of cellulose extracted was found higher than raw material.

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