scholarly journals Characterization of cellulose and sugarcane (Saccharum spp.) straw from five cultivars grown in the humid tropic of Mexico

Author(s):  
Liliana Yanet López-Velázquez ◽  
Sergio Salgado-García ◽  
Samuel Cordova-Sánchez ◽  
Cintya Valerio-Cardenas ◽  
Gloria Ivette Bolio-Lopez ◽  
...  

Objective: The aim of this study was to determine the cellulose content and characteristics of sugarcane straw from the cultivars MEX 69-290, MEX 68-P-23, CO-997, SP 70-1284 and CP 72-2086. Design/methodology/approach: A completely random experimental design with six replicates was conducted; the study factor was the sugarcane straw from the five evaluated cultivars. For cellulose extraction, the sodium hydroxide (soda) method was used on dried sugarcane straw of 2 mm. The crystallinity and crystal size were determined with x-ray diffraction (XRD); the fiber length had achieved a measurement with a DMRE optical microscope.   Results: Among the results, it can be noted that the cultivars MEX 69-290 and SP 70-1284, which presented less cellulose content (8.4 g and 8.5 g) and lower yields (42.1% and 42.6%), while the cultivar CO-997, presented higher cellulose content and yield which ranged from 9.8 g to 49.8%. The crystallinity of cellulose was higher in the sugarcane straw from the cultivars SP 70-1284 and MEX 68-P23. The crystal size of cellulose was 2.3 nm. The length of cellulose fibers was small (<945.7 µm). Study limitations/implications: The collection of samples in the field, as well as selected materials for digestion. Findings/conclusions: The sugarcane straw is a potential source of cellulose for the paper industry.  

2013 ◽  
Vol 834-836 ◽  
pp. 309-314
Author(s):  
Zi Fan Xiao ◽  
Jin Shu Cheng ◽  
Jun Xie

A glass-ceramic belonging to the CaO-Al2O3-SiO2(CAS) system with different composition of spodumene and doping the Li2O with amount between 0~2.5 % (mass fraction) were prepared by onestage heat treatment, under sintering and crystallization temperature at 1120 °C for two hours. In this paper, differential thermal analysis, X-ray diffraction, scanning electron microscopy, energy dispersive spectrometry and bending strength test were employed to investigate the microstructure and properties of all samples. β-wollastonite crystals were identified as the major crystalline phases, and increasing Li2O was found to be benefit for the crystallization and tiny crystalline phases remelting, resulting in the content of major crystalline phases increased first and then decreased with increasing the expense of spodumene. Meanwhile, the crystal size can be positively related with the content of Li2O. The preferable admixed dosage of spodumene can be obtained, besides the strength of glass-ceramics can be more than 90 MPa.


2014 ◽  
Vol 660 ◽  
pp. 942-946
Author(s):  
Mohamad Firdaus Abdul Wahid ◽  
C.M. Mardziah ◽  
Koay Mei Hyie ◽  
N.R. Nik Roselina

Hydroxyapatite was prepared by using precipitation method. The substitution of zinc ions in hydroxyapatite structure was studied by several characterization techniques. Several concentration of zinc ions were substituted into hydroxyapatite. Characterization technique such as X-ray diffraction method was used to study the phase changes and the lattice parameters with the addition of zinc. Field emission scanning electron microscopy was used to examine the influence of zinc on the crystal size and the morphology of the as-synthesized powders. Based on X-ray diffraction result, the addition of zinc affects the lattice parameters and phase. The result showed that zinc ions were substituted in the structure. As zinc substitution increased, the lattice parameters a and c decreased. The crystal shape of hydroxyapatite without zinc ions was regular shapes while hydroxyapatite with zinc ions was irregular and also tends to agglomerates with single particle was calculated about 28 - 34 nm .


2016 ◽  
Vol 720 ◽  
pp. 290-295
Author(s):  
Veni Takarini ◽  
Alfend Rudyawan ◽  
Andri Hardiansyah ◽  
Rifki Septawendar ◽  
Niki Prastomo ◽  
...  

This study prepared Magnesium-Partially Stabilized Zirconia (Mg-PSZ) filler synthesis and direct foaming technique using egg whites, and impregnated by PMMA. The results were evaluated systematically by X-ray diffraction (XRD), Scanning Electron Microscope (SEM), and Transmission Electron Microscope (TEM). XRD results denote that the powder sample of MgPSZ was successfully formed with various crystal size of tetragonal and monoclinic phase. SEM and TEM observations revealed that nanoparticles MgPSZ were in spherical and long rounded shapes. Furthermore, SEM observation revealed that the direct foaming method were also successful in the formation of porous structures which favourable for impregnation process by PMMA. The use of egg whites as a polymer precursor in both methods demonstrates that porous specimens contained nanosized, predominantly tetragonal, Mg-PSZ powders were successfully synthesized. This shall yield an interesting prospect towards cheap, reliable, and biocompatible product to resemble the modulus elasticity of dentin.


2017 ◽  
Vol 3 (1) ◽  
pp. 20-26
Author(s):  
Atik Setyani ◽  
Emas Agus Prastyo Wibowo

Nanotubes received great attention because it has a high surface area. In this study, TiO2 nanotubes fabricated via hydrothermal method from  synthesis of TiO2 nanoparticles via sol-gel method. Catalysts that have been synthesized later in the characterization by X-Ray Diffraction (XRD) to obtain the crystal size and crystallinity. Crystal size of TiO2 nanoparticles at a temperature of 450C is 13.78 nm. Then characterized by Transmission Electron Microscopy (TEM) to look at the formation of nanotubes. Characterization of TiO2 nanotubes with TEM shows that the structure of the tubes had already been formed TNTs although the growth has not been perfect. It can be seen from the structure TNTs who tend to be short and yet so irregular.DOI: http://dx.doi.org/10.15408/jkv.v0i0.5036  


Author(s):  
Yasmine Mahmoud ◽  
Zitouni Safidine ◽  
Naima Belhaneche-Bensemra

In this study, microcrystalline cellulose (MCC) was isolated from walnut and apricot shells (WS and AS) as agricultural wastes in order to use it as reinforcement in polymer composites. The microcrystalline cellulose was extracted by alkaline treatment and bleached by peroxide as an environmentally friendly treatment, called walnut cellulose (WC) and apricot cellulose (AC). The chemical composition of the samples was set according to the Technical Association of Pulp and Paper Industry (TAPP). After treatments, the alpha-cellulose content increased by about 23 % for the two used cellulose sources. The structural and morphological properties of the samples were investigated by Fourier transform infrared spectroscopy in the attenuated total reflectance mode (ATR-FTIR), optical microscopy (OM), X-ray diffraction and scanning electron microscopy (SEM). The crystallinity index values evaluated for WC and AC via X-ray diffraction were respectively 86.4 and 80.3 %. The alkaline soluble fractions of walnut (ASW) and apricot (ASA) shells were recovered and characterized by OM and ATR-FTIR spectroscopy. Furthermore, their chemical composition was analyzed. The characterization and the properties of the WC and AC were similar to those of commercial MCC and MCC prepared in literature from wood and some agricultural wastes.


Author(s):  
N. Yuvaraj ◽  

Aluminum-based surface composites were fabricated by the TIG arc process. B4C micro and nanoparticles were filled separately on the grooves of the Aluminum substrate and modified the surfaces with different TIG arc speeds. The modified composite surface was characterized by optical microscope, Scanning Electron microscope, and X-ray diffraction. The microhardness and wear properties of the composite surface were evaluated. The results of this study revealed that the newly formed nanocomposite surface enhances the hardness and wear characteristics. The wear worn-out surfaces of the composite surface were analyzed through SEM studies in order to understand the wear mechanisms


2021 ◽  
Vol 922 (1) ◽  
pp. 012072
Author(s):  
Ratna ◽  
S Aprilia ◽  
N Arahman ◽  
A A Munawar

Abstract The study aimed to characterize cellulose nanocrystalline (NCCs) from banana peduncles using acid hydrolysis. The NCCs isolation process was done by hydrolysis using H2SO4 with concentrations of 1M, 2M, and 3M at a microwave power of 100 Watts within 1 hour of hydrolysis. The product of NCCs was characterized in term of yield, chemical composition (by FTIR), and its crystallinity. The result showed that the highest yield of 88.33% was obtained in acid hydrolysis at the concentration of 1M H2SO4. The results of the FTIR test showed that non-cellulose content had been removed and demonstrated that the molecular structure of cellulose does not change even when treated at different acid concentrations. X-Ray Diffraction analysis showed that crystallinity decreased by increasing the sulfamic acid concentration. The thermogravimetric analysis confirmed the heat resistance analysis and showed that the NCCs is gradually decomposed at a temperature range of 268.3–415.25 ¼C. The colour of cellulose nanocrystalline powder darkens as the sulfuric acid concentration increases.


2019 ◽  
Vol 280 ◽  
pp. 04003
Author(s):  
Agus Mirwan ◽  
Meilana Dharma Putra ◽  
Riani Ayu Lestari

The existence of peat clay is scattered in many parts of the world with the huge amount. The high compound of minerals in the peat clay can be potentially used as adsorbent and catalyst. This research aims to study the composition of peat clay and functional group of the compound in the peat clay. The characterization of x-ray fluorescence (XRF), fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), and scanning electron microscope-energy dispersive x-ray (SEM- EDX) were assigned to compare the sample before and after calcination process at 700 oC 120 min. FTIR analysis showed the presence of quartz, kaolinite, hematite, illite in peat clay. The results of XRF analysis showed that chemical composition of peat clay was dominantly in the form of silica oxide (18%), aluminum oxide (7%), and iron oxide (15%). The amount of compounds was observed to increase to be 32%, 18% and 11%, respectively after calcinations. XRD analysis confirmed the presence of this mineral in the peat clay. SEM analysis showed flake structure of peat clay with EDX which indicated composition of the dominant element namely the presence of Al, Si, and Fe before and after calcination. This high amount of minerals in peat clay led to potential source to be utilized as adsorbent for removing the pollutant or as and catalyst for chemical process.


2010 ◽  
Vol 129-131 ◽  
pp. 1201-1205 ◽  
Author(s):  
Hai Li Yang ◽  
Ai Min Gao ◽  
Yu Zhu Zhang ◽  
Yun Gang Li ◽  
Guo Zhang Tang ◽  
...  

Fe3Si layer was prepared by pulse eletrodeposition of Si on the surface of non-oriented steel in molten salts. With an orthogonal test the optimal process parameters were determined: the formulation of salts was NaCl:KCl:NaF:SiO2=1:1:3:0.3(mole ratio), current density of 60 mA/ cm2, duty cycle of 30%, pulse period of 1000 s and a deposition time of 50 min, respectively. The compositional depth profile, the structure, the surface morphology and cross sectional micrograph of the layer were studied by glow discharge spectrometry (GDS), X ray diffraction (XRD), scanning electron microscopy (SEM) and optical microscope (OM). The results showed that Si in the layer existed in the form of the gradient distribution. The phase structure of the layer was composed of the single-phase Fe3Si. The layer composed of equiaxed grains. The surface appeared smooth and dense, and with uniform thickness.


2011 ◽  
Vol 117-119 ◽  
pp. 1433-1436 ◽  
Author(s):  
Feng Hong Li ◽  
Yong Sun ◽  
San Xi Li ◽  
Shao Jun Ma

A series of acylated chitosan oligosaccharides (LCSOs) were synthesized by reacting chitosan oligosaccharide (CSO) with lauroyl chloride in methane sulfonic acid. The chemical structures of LCSOs were characterized by Fourier transform infrared. Differential scanning calorimetry (DSC) showed that LCSOs had two phase transitions during heating. Thermoplastic chitosan oligosaccharide (LCSO-4) has distinct melting temperature (Tm) at 64 °C and 110°C. X-ray diffraction (XRD) analyses indicated that the crystal structure of CSO was changed through acylation and had created new crystal domains of lauroyl side chains. New strong diffraction peaks were observed around 2θ values of 20.0°, 21.5° and 26.3° for thermoplastic acylated chitosan oligosaccharide (LCSO-4). The melting and crystallization properties of thermoplastic acylated chitosan oligosaccharide were observed by polarized optical microscope (POM).


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