Preparation of Starch Nanoparticles via High-Energy Ball Milling

2016 ◽  
Vol 40 ◽  
pp. 174-179 ◽  
Author(s):  
Hua Lin ◽  
Li Zhao Qin ◽  
He Hong ◽  
Qing Li

Nano-sized starch particles were prepared from potato starch via high-energy ball milling, which is a purely physical method. Scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and viscometer were used to analyze the morphology and characteristics of the as-prepared nanoparticles. Spherical particles with an average size of approximately 120 nm were obtained after grinding the samples for 90 min, and the particles were free from any contamination. The particle surface was rough with a plush-like feature, and the adsorption ability was six times higher than that of native starch. Thus, the nano-sized starch particles can be used as a good embedding medium in biomedical and chemical materials.

2013 ◽  
Vol 755 ◽  
pp. 47-52 ◽  
Author(s):  
J.R. Romero-Romero ◽  
J. Luis López-Miranda ◽  
R. Esparza ◽  
M.A. Espinosa-Medina ◽  
G. Rosas

In this study, FeAl2 and Fe2Al5 intermetallic alloys were prepared by conventional casting technique. In order to study their structural stability the alloys were subjected to high-energy ball milling process for 1, 2.5, 5 and 10 h. The structural and chemical characterizations were conducted by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and differential scanning calorimetry. After 10 h of milling, the experimental results indicated a phase transformation from FeAl2-triclinic phase to Fe2Al5-ortorrombic structure. This phase transformation is characterized by a change from low to high symmetry systems.


Metals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1908
Author(s):  
Tomasz Goryczka ◽  
Piotr Salwa

A high-energy ball milling technique was used for production of the equiatomic NiTi alloy. The grinding batch was prepared in two quantities of 10 and 20 g. The alloy was produced using various grinding times. Scanning electron microscopy, X-ray diffraction, hardness measurement and differential scanning calorimetry were used for materials characterization at various milling stages. The produced alloy was studied by means of microstructure, chemical and phase composition, average grain and crystallite size, crystal lattice parameters and microstrains. Increasing the batch mass to 20 g and extending the grinding time to 140 h caused the increase in the average size of the agglomerates to 700 µm while the average crystallites size was reduced to a few nanometers. Microstrains were also reduced following elongation of milling time. Moreover, when the grinding time is extended, the amount of the monoclinic phase increases at the expense of the body-centered cubic one—precursors of crystalline, the B2 parent phase and the B19′ martensite. Crystallization takes place as a multistage process, however, at temperatures below 600 °C. After crystallization, the reversible martensitic transformation occurred with the highest enthalpy value—4 or 5 J/g after 120 and 140 h milling, respectively.


2013 ◽  
Vol 745-746 ◽  
pp. 281-285
Author(s):  
Y.B. Yuan ◽  
Rui Xiao Zheng ◽  
Su Jing Ge ◽  
Han Yang ◽  
Chao Li Ma

Al86Ni7Y4.5Co1La1.5 (at.%) alloy powder was produced by argon gas atomization process. After high-energy ball milling, the powder was consolidated and extruded by using vacuum hot press sintering under different process conditions, sintering temperature, extrusion pressure, sintering time, etc.. The microstructure and morphology of the powder and consolidated bulk alloy were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The phase transformation of the powder was investigated by differential scanning calorimetry (DSC). Mechanical properties of the consolidated bulk alloy were examined. The results showed that as the milling time increase, the volume fraction of amorphous materials and the hardness and yield strength of the bulk alloy were obvious improved.


2006 ◽  
Vol 510-511 ◽  
pp. 698-701
Author(s):  
Pyuck Pa Choi ◽  
Young Soon Kwon ◽  
Ji Soon Kim ◽  
Dae Hwan Kwon

Mechanically induced crystallization of an amorphous Fe90Zr10 alloy was studied by means of X-ray diffraction (XRD) and differential scanning calorimetry (DSC). Under high-energy ball-milling in an AGO-2 mill, melt-spun Fe90Zr10 ribbons undergo crystallization into BCC α- Fe(Zr). Zr atoms are found to be solved in the Fe(Zr) grains up to a maximum supersaturation of about 3.5 at.% Zr, where it can be presumed that the remaining Zr atoms are segregated in the grainboundaries. The decomposition degree of the amorphous phase increases with increasing milling time and intensity. It is proposed that the observed crystallization is deformation-induced and rather not attribute to local temperature rises during ball-collisions.


1994 ◽  
Vol 9 (1) ◽  
pp. 53-60 ◽  
Author(s):  
D.L. Zhang ◽  
T.B. Massalski

Solid state reactions induced by high energy ball milling between Pd and Si have been studied. X-ray diffractometry and differential scanning calorimetry have been used to characterize the resulting phases. During milling, Pd and Si react by diffusion to form different phases depending on the Si content in the starting mixture. With a low Si content of 19 at. %, an amorphous phase forms of the same composition. On continued milling, this amorphous phase partially crystallizes into Pd9Si2 and Pd2Si compounds. With the Si content equal to or higher than 33 at. %, no amorphous phases were observed. Instead, the Pd2Si phase is produced. For powder composition corresponding to the stoichiometric compound Pd2Si (33 at. % Si), the Pd2Si forms and remains stable during further milling. With Si content equal to or higher than 50 at. %, the initially produced Pd2Si is destabilized by a reaction with the remaining Si to form PdSi, which is a metastable phase at the temperature of ball milling. It is very unlikely that an amorphous phase of a composition equal to or higher than 33 at. % Si could be produced by ball milling in the Pd-Si system. This is because the Pd2Si phase forms very easily through the reaction between Pd and Si, and this reaction competes effectively with glass formation.


2003 ◽  
Vol 775 ◽  
Author(s):  
J. Eric Hampsey ◽  
Claudio L. De Castro ◽  
Byron F. McCaughey ◽  
Donghai Wang ◽  
Brian S. Mitchell ◽  
...  

AbstractHighly ordered mesoporous silica particles with sizes in the micron to sub-micron range are of great interest due to their applications as catalysts and filler materials. Currently, mesoporous silica particles are synthesized using large amounts of solvent, which is impractical for large scale-up in industry. This paper reports on a high-energy ball milling process that has been employed to create micron to sub-micron sized mesoporous silica particles starting from a silica xerogel prepared by a surfactant self-assembly sol-gel process. We have studied the effect of parameters such as milling media (e.g., zirconia, stainless steel, and steel centered nylon balls), milling time, the presence of surfactants during milling, particle size, and pore structure. Results from transmission electron microscopy (TEM), scanning electron microscopy (SEM), Xray diffraction (XRD), and nitrogen adsorption demonstrate the feasibility of producing large quantities of mesostructured particles by a simple milling process.


2013 ◽  
Vol 22 ◽  
pp. 140-147
Author(s):  
SHEELA DEVI ◽  
A. K. JHA

Nanocrystalline BaTi 0.095 W 0.05 O 3 has been synthesized by mechanical activation process using high-energy ball milling. The powders milled for (10 hours, 20 hours, 30 hours respectively) were characterized by X-ray diffraction (XRD) and Scanning electron microscopy (SEM). Transmission electron microscopy images showed that in W- substituted barium titanate nanoparticles are formed in the range of 20–50 nm. Crystallite size decreases with increasing milling time in the samples. Detailed Dielectric and ferroelectric properties with different milling times are discussed in detail. Diffusivity of the samples increases with milling time. Piezoelectric properties increase with increase in milling time in the samples.


Metals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 370
Author(s):  
Ashutosh Sharma ◽  
Min Chul Oh ◽  
Myoung Jin Chae ◽  
Hyungtak Seo ◽  
Byungmin Ahn

In this work, we have investigated the role of high-energy ball milling (HEBM) on the evolution of microstructure, thermal, and wetting properties of an Sn-0.7Cu alloy. We ball-milled the constituent Sn and Cu powders in eutectic composition for 45 h. The microstructural studies were carried out using optical and scanning electron microscopy. The melting behavior of the powder was examined using differential scanning calorimetry (DSC). We observed a considerable depression in the melting point of the Sn-0.7Cu alloy (≈7 °C) as compared to standard cast Sn-0.7Cu alloys. The resultant crystallite size and lattice strain of the ball-milled Sn-0.7Cu alloy were 76 nm and 1.87%, respectively. The solderability of the Sn-0.7Cu alloy was also improved with the milling time, due to the basic processes occurring during the HEBM.


2015 ◽  
Vol 1766 ◽  
pp. 181-186
Author(s):  
G. Rosas ◽  
J. Chihuaque ◽  
E. Bedolla ◽  
R. Esparza ◽  
R. Pérez

ABSTRACTIn this investigation, the chemical and microstructural characteristics of nanostructured AlFe intermetallic produced by high-energy ball milling have been explored. High purity elemental powders were used as the starting material. The ball milling was carried out at room temperature using a SPEX-8000 mixer/mill. The structure, morphology and compositions of the powders were obtained using X-ray diffraction patterns (XRD), scanning and transmission electron microscopy (STEM). High resolution electron microscopy observations have been used in the nanostructured materials characterization. The structural configurations have been explored through comparisons between experimental HREM images and theoretically simulated images obtained with the multislice method of the dynamical theory of electron diffraction.


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