scholarly journals The effects of rheological properties of wall materials on morphology and particle size distribution of microcapsule

2010 ◽  
Vol 28 (No. 5) ◽  
pp. 433-439 ◽  
Author(s):  
Y. Xie ◽  
A. Wang ◽  
Q. Lu ◽  
M. Hui
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Rheological Properties ◽  
Size Distribution ◽  
Spray Drying ◽  
Average Diameter ◽  
Core Material ◽  
Viscous Modulus ◽  
Wall Materials ◽  
Paste Viscosity

The effects of rheological properties of the wall materials on the morphology and particle size distribution of microcapsules prepared by spray-drying were evaluated. Gelatin-sucrose (Gel-Suc), gelatin-peach-gum-sucrose (Gel-PG-Suc), and HI-CAP 100 were used as wall materials with vitamin A as a model core material. Scanning electron microscopy (SEM) showed that microcapsules produced with Gel-Suc exhibited cracks while Gel-PG-Suc produced a smooth surface with few pores, and HI-CAP100 a rounded surface containing characteristic concavities. The volume average diameter (D<sub>4,3</sub>) showed significant variations from 73.9 &plusmn; 1.02 &micro;m and 68.7 &plusmn; 0.85 &micro;m to 29.9 &plusmn; 0.94 &micro;m (P &lt; 0.05). Rheometry indicated that the wall paste viscosity was inversely proportional to the shear rate. Viscosity ranking was Gel-Suc &gt; Gel-PG-Suc &gt; HI-CAP 100. Gel-Suc showed the highest elastic modulus (G') and viscous modulus (G'' values), followed by Gel-PG-Suc and HI-CAP 100. Gel-Suc was associated with moderate quantities of broken microcapsules while HI-CAP 100 generated numerous microcapsules with characteristic dents generated during spray-drying.

Process Factors Using Centrifugal Spray Drying to Prepare Bauxite Microspheres

2011 ◽  
Vol 399-401 ◽  
pp. 828-833
Author(s):  
Xiao Su Cheng ◽  
Meng Qi Peng ◽  
Yu Fa Zhong
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Spray Drying ◽  
Average Diameter ◽  
Optimal Operation ◽  
Solid Content ◽  
Diameter Distribution ◽  
Drying Process ◽  
Process Factors

The centrifugal spray drying process of bauxite slurry was studied to investigate the influence of slurry solid content on the particle size distribution and the sphericity of the microspheres, and so was operation technology on average diameter and the sphericity of the microspheres. The optimal operation parameters are obtained to prepare high spherical microspheres bauxite with the diameter distribution of 100 μm and whose particle size distribution is narrow: the slurry solid content is 70 wt%, the dry air temperature is 250 °C, the rotation rate of spray head is 6000 rpm and the feed flow rate is 1 L/h in the experiments.

scholarly journals RESEARCH OF THE EJECTING PROPERTIES OF A POLYFRACTION BULK MATERIAL FLOW

2018 ◽  
Vol 3 (3) ◽  
pp. 46-51
Author(s):  
Евгений Попов ◽  
Evgeniy Popov
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Material Flow ◽  
Bulk Material ◽  
Aerodynamic Resistance ◽  
Average Diameter ◽  
Resistance Coefficient ◽  
Free Falling ◽  
The Given

This work is aimed at confirming the adequacy of the probabilistic and statistical approach to determining the aerodynamic resistance coefficient of particles in a flow of the free falling polyfractional material, suggested by the author. The aerodynamic resistance coefficient of particles in a flow of falling material is defined by calculating the probability of finding particles out of air shadows of the neighboring particles. The laboratory experiment was performed on the offered experimental samples of bulk materials having different particle size distribution, but the identical average diameter of particles. The design of a laboratory experimental installation which allows determining the consumption of air, ejected by a polyfractional material flow, was described. The amount of the air, ejected with experimental samples, depends on their particle size distribution that confirms the insufficiency of describing the properties of bulk material only with the average diameter value. The given comparison of results of the analytical calculations with experimental data shows the reliability and adequacy of the calculated values.

scholarly journals Effect of particle size distribution on rheological properties of chocolate

2020 ◽  
Vol 11 (11) ◽  
pp. 9547-9559
Author(s):  
Annika Feichtinger ◽  
Elke Scholten ◽  
Guido Sala
Keyword(s):  
Surface Roughness ◽  
Particle Size ◽  
Particle Size Distribution ◽  
Rheological Properties ◽  
Size Distribution ◽  
Particle Shape ◽  
Size Ratio ◽  
Particle Size Ratio ◽  
Effect Of Particle Size

Particle size distribution and particle size ratio have an important effect on rheological properties of model chocolate samples, but also other factors like particle shape, surface roughness and hydrophilicity should be taken into account.

Adjusting rheological properties of concentrated microgel suspensions by particle size distribution

2015 ◽  
Vol 49 ◽  
pp. 183-191 ◽  
Author(s):  
Christian Hahn ◽  
Stefan Nöbel ◽  
Ramona Maisch ◽  
Wiebke Rösingh ◽  
Jochen Weiss ◽  
...  
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Rheological Properties ◽  
Size Distribution

Particle Size Distribution of SBR and NBR Latexes by UV-VIS Turbidimetry near the Rayleigh Region

1996 ◽  
Vol 69 (4) ◽  
pp. 696-712 ◽  
Author(s):  
Mario A. Llosent ◽  
Luis M. Gugliotta ◽  
Gregorio R. Meira
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Average Diameter ◽  
Styrene Butadiene Rubber ◽  
Butadiene Rubber ◽  
Data Treatment ◽  
Distribution Shape ◽  
Soft Polymer ◽  
Styrene Butadiene

Abstract This paper deals with data treatment problems that arise when turbidimetry is employed to estimate the particle size distribution (PSD) of soft polymer latexes with low diameter limits around 40 nm. Scanning electron microscopy and dynamic light scattering were used as comparison techniques. Industrial latexes of styrene-butadiene rubber (SBR) and of acrylonitrile-butadiene rubber (NBR) were investigated. The data treatment involved the use of Mie's Model to obtain an average diameter and/or the complete PSD. For estimating the complete PSD, a least squares optimization (with an imposed distribution shape) and a numerical deconvolution procedure (without assumptions on the distribution shape) were attempted. A synthetic example was solved to investigate the limits of the applied numerical methods. For the polymer refractive index functions, Cauchy's Law was used — and its adequate adjustment proved essential for good turbidimetric estimations. A reasonable agreement between the turbidity measurements and the other independent estimations was verified. For the SEM observations, the soft latexes were hardened by irradiation before observation, but negligible diameter variations were detected.

scholarly journals Dense suspensions formulations for upgrading processes in heavy and extra heavy crude oil

2011 ◽  
Vol 4 (3) ◽  
pp. 61-72
Author(s):  
Lilia Rodríguez ◽  
Geoffrey Viviescas
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Crude Oil ◽  
Rheological Properties ◽  
Size Distribution ◽  
Pilot Plant ◽  
Attractive Alternative ◽  
Heavy Crude Oil ◽  
Heavy Crude ◽  
By Products

The present work involved the formulation of solid-liquid suspensions of by-products of heavy and extra heavy crude oil process upgrades, coke and asphaltenes from Delayed coking and Deasphalting processes. This was done by controlling rheological properties and following specifications for pipeline transmission, similar to those of liquid hydrocarbons. The formulated products guarantee the possibility of moving the by products in a fluidized way, minimizing storage, handling, environmental and operational costs in transportation, and providing an attractive alternative as non conventional fuel. Regarding the formulation of suspensions, it was necessary to establish the effect of formation components such as: surfactants, stabilizers, as well as the type, amount of solids and particle size ratio on the flow properties of the resulting product. The parameters analyzed for rheological properties of pipeline transport were viscosity, particle size distribution, static and dynamic stability. Laboratory tests were performed in high precision rheometers -TA Instruments RX1500 and Haake RS600- and Mastersizer 2000 particle size analyzer. At pilot scale, we used a closed loop to verify flow parameters, including normal and critical transport scenarios: Sudden shutdowns and extended ones of up to 72 hours, with subsequent pumping re-starts. Tests performed at the lab and the pilot plant showed better rheological properties in the formulations with bimodal particle size distribution. This allowed higher loads of solid, up to 52%, and an improved mobility, reflected as lower viscosity. A non-Newtonian rheological behavior became evident, characterized by yield stress to ensure pumpability after prolonged inactivity. The pressure drops and calculation of apparent viscosity obtained in the pilot plant were compared and verified with lab results, showing reproducibility.

scholarly journals Effect of inulin and galactooligosaccharides on particle size distribution and rheological properties of prebiotic ketchup

2016 ◽  
Vol 20 (1) ◽  
pp. 157-170 ◽  
Author(s):  
Samar Mansouripour ◽  
Maryam Mizani ◽  
Sousan Rasouli ◽  
Abbas Gerami ◽  
Anousheh Sharifan
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Rheological Properties ◽  
Size Distribution
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