Mean Particle Diameters. Part IV: Empirical Selection of the Proper Type of Mean Particle Diameter Describing a Product or Material Property

2004 ◽  
Vol 21 (3) ◽  
pp. 179-196 ◽  
Author(s):  
Maarten Alderliesten
Keyword(s):  
Material Property ◽  
Particle Diameter ◽  
Mean Particle Diameter ◽  
Selection Of

Preparation and Evaluation of Chitosan Loaded Naproxen Nanoparticles by Emulsion Interfacial Reaction Method

2019 ◽  
Vol 9 (2) ◽  
pp. 89-96
Author(s):  
Abbaraju Krishna Sailaja ◽  
Juveria Banu
Keyword(s):  
Drug Release ◽  
Interfacial Reaction ◽  
Polymer Concentration ◽  
Chitosan Nanoparticles ◽  
Particle Diameter ◽  
Entrapment Efficiency ◽  
Reaction Method ◽  
Release Data ◽  
Mean Particle Diameter

Aim: The aim of this investigation was to develop and characterize naproxen loaded chitosan nanoparticles by emulsion interfacial reaction method. Methodology: For emulsion interfacial reaction method chitosan was used as a polymer. In this method, eight formulations were prepared by varying drug to polymer concentration. Discussion: Out of eight formulations prepared using emulsion interfacial reaction method EI8 formulation was found to be the best formulation. The drug content was observed as 94.4%, entrapment efficiency and loading capacity were found to be 87.5% and 75%, respectively. The mean particle diameter was measured as 324.6nm and the Zeta potential value was found to be -42.4mv. In vitro drug release data showed 97.2% of drug release rate sustained up to 12hrs. Conclusion: The results clearly reveal that EI8 formulation having the highest amount of drug was considered as the best formulation because of its small mean particle diameter, good entrapment efficiency, and stability.

scholarly journals Effects of Turbine Design on Particulate Erosion of Turbine Airfoils

1991 ◽  
Author(s):  
J. H. Wagner ◽  
B. V. Johnson ◽  
D. W. Geiling
Keyword(s):  
Gas Turbines ◽  
Combustion Process ◽  
Particle Diameter ◽  
Surface Erosion ◽  
Erosion Rates ◽  
Trajectory Calculations ◽  
Design Characteristics ◽  
Turbine Airfoils ◽  
Turbine Design ◽  
Selection Of

An analytic study was conducted to determine the effects of turbine design, airfoil shape and material on particulate erosion of turbine airfoils in coal-fueled, direct-fired gas turbines used for electric power generation. First-stage, mean-line airfoil sections were designed for 80 MW output turbines with 3 and 4 stages. Two-dimensional particle trajectory calculations and erosion rate analyses were performed for a range of particle diameters and densities and for ductile and ceramic airfoil materials. Results indicate that the surface erosion rates can vary by a factor of 5 and that erosion on rotating blades is not well correlated with particle diameter. The results quantify the cause/effect turbine design relationships expected and assist in the selection of turbine design characteristics for use downstream of a coal-fueled combustion process.

scholarly journals Preparation and Component Optimization of Resin-Based Permeable Brick

Materials ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 2701
Author(s):  
Xiaofu Wang ◽  
Xiong Zhang
Keyword(s):  
Particle Diameter ◽  
Characteristic Parameter ◽  
Dynamic Mechanical Properties ◽  
Mechanical Analysis ◽  
Fine Aggregate ◽  
Test Results ◽  
Dynamic Mechanical ◽  
Aggregate Distribution ◽  
Particle Group ◽  
Selection Of

The present study aims to prepare resin-based permeable bricks with micron-sized pores using fine aggregate with a particle diameter of 0.08–0.6 mm and bisphenol-A epoxy resin, a polymer binder. The properties of the binder, the characteristic parameters of the aggregate, and the micro pore structure of the brick were studied in order to break through the limitations of traditional porous permeable materials. The dynamic mechanical properties of resin were analyzed by dynamic mechanical analysis (DMA). The frequency parameter of particle size of 10 kinds of aggregate from different regions were obtained by digital image processing, and the characteristic parameter (aggregate distribution coefficient α) was obtained by modified Gaussian distribution. The microstructure of porous brick was analyzed by scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDS). The test results show: (1) the glass transition temperature (Tg) of the resin is 61 °C; (2) the parameters of aggregate particle group will affect the performance of porous permeable materials; (3) the minimum effective pore diameter of the permeable brick is 30 μm, the maximum permeable rate is 6.22 × 10 − 2   cm / s and the compressive strength is 41.08 MPa. The conclusions of this study will provide an important reference for permeable materials in the micron-scale pore range and the selection of binder and aggregate materials.

Prediction of the deflagration index for organic dusts as a function of the mean particle diameter

2017 ◽  
Vol 50 ◽  
pp. 67-74 ◽  
Author(s):  
Anna Fumagalli ◽  
Marco Derudi ◽  
Renato Rota ◽  
Jef Snoeys ◽  
Sabrina Copelli
Keyword(s):  
Particle Diameter ◽  
Deflagration Index ◽  
The Mean ◽  
Mean Particle Diameter

Influence of nucleating agent type on the morphology of extruded polyetherimide foam for printed circuit boards*

2019 ◽  
Vol 56 (3) ◽  
pp. 317-341 ◽  
Author(s):  
Clemens Keilholz ◽  
Daniel Raps ◽  
Thomas Köppl ◽  
Volker Altstädt
Keyword(s):  
Surface Tension ◽  
Printed Circuit Boards ◽  
Particle Diameter ◽  
Nucleating Agent ◽  
Nucleating Agents ◽  
Circuit Boards ◽  
Printed Circuit ◽  
Foam Morphology ◽  
The Mean ◽  
Mean Particle Diameter

This work focuses on the development of foamed high temperature thermoplastic substrates for printed circuit boards. For this application it is necessary to achieve mean cell diameters smaller than 30 µm in order to be able to realize vias and high packaging densities (miniaturization). Different additives as nucleating agents, namely macro- and micro-crystalline talc, silica, calcium carbonate, and wollastonite, were melt-compounded with polyetherimide using a twin-screw extruder. Foamed samples are prepared by foam extrusion using a slit die and CO2 as physical blowing agent. The aim of this study is to analyze the influence of the mean particle size and the particle surface tension on the mean cell diameters. Therefore, the shape of the additives, the foam morphology, and the elongational viscosity were considered. The additives with a suitable particle size and surface tension exhibit a positive influence on the foam morphology, resulting in smaller cell diameters (<30 µm), a narrower cell size distribution and a foam density lower than 900 kg/m3. If the mean particle diameter of the nucleating agents is lower than 0.6 µm in this study, no nucleation effect could be observed. This is related to the fact that no heterogeneous nucleation occurs, if the particle diameter is too small. If the mean particle diameter of the used additives is larger than 1.5 µm, which could be demonstrated in this study in case of polyetherimide, then the additive acts as nucleating agent and heterogeneous nucleation occurs. Furthermore, it was observed that the mean cell diameter was affected by the different surface tensions of the studied nucleating agents.

scholarly journals Vertically-resolved particle size distribution within and above the mixing layer over the Milan metropolitan area

2010 ◽  
Vol 10 (8) ◽  
pp. 3915-3932 ◽  
Author(s):  
L. Ferrero ◽  
M. G. Perrone ◽  
S. Petraccone ◽  
G. Sangiorgi ◽  
B. S. Ferrini ◽  
...  
Keyword(s):  
Size Distribution ◽  
Fine Particles ◽  
Potential Temperature ◽  
Mixing Layer ◽  
Particle Diameter ◽  
Coarse Particle ◽  
Growth Speed ◽  
Average Increase ◽  
Mixing Height ◽  
Mean Particle Diameter

Abstract. Vertical aerosol profiles were directly measured over the city of Milan during three years (2005–2008) of field campaigns. An optical particle counter, a portable meteorological station and a miniaturized cascade impactor were deployed on a tethered balloon. More than 300 vertical profiles were measured, both in winter and summer, mainly in conditions of clear, dry skies. The mixing height was determined from the observed vertical aerosol concentration gradient, and from potential temperature and relative humidity profiles. Results show that inter-consistent mixing heights can be retrieved highlighting good correlations between particle dispersion in the atmosphere and meteorological parameters. Mixing height growth speed was calculated for both winter and summer showing the low potential atmospheric dispersion in winter. Aerosol number size distribution and chemical composition profiles allowed us to investigate particle behaviour along height. Aerosol measurements showed changes in size distribution according to mixing height. Coarse particle profiles (dp>1.6 μm) were distributed differently than the fine ones (dp<1.6 μm) were, at different heights of the mixing layer. The sedimentation process influenced the coarse particle profiles, and led to a reduction in mean particle diameter for those particles observed by comparing data above the mixing height with ground data (−14.9±0.6% in winter and −10.7±1.0% in summer). Conversely, the mean particle diameter of fine particles increased above the mixing height under stable atmospheric conditions; the average increase, observed by comparing data above the mixing height with ground data, was +2.1±0.1% in winter and +3.9±0.3% in summer. A hierarchical statistical model was created to describe the changes in the size distribution of fine particles along height. The proposed model can be used to estimate the typical vertical profile characterising launches within pre-specified groups starting from: aerosol size and meteorological conditions measured at ground-level, and a mixing height estimation. The average increase of fine particle diameter, estimated on the basis of the model, was +1.9±0.5% in winter and +6.1±1.2% in summer, in keeping with experimental findings.

The Entrapment of Vitamin E in Nanostructured Lipid Carriers of Rambutan Seed Fat for Cosmeceutical Uses

2016 ◽  
Vol 675-676 ◽  
pp. 77-80 ◽  
Author(s):  
Kwansiri Uraiwan ◽  
Chutimon Satirapipathkul
Keyword(s):  
Vitamin E ◽  
Solid Lipid Nanoparticles ◽  
Particle Diameter ◽  
Lipid Nanoparticles ◽  
Nanostructured Lipid Carriers ◽  
Chemical Effect ◽  
Tween 20 ◽  
Solvent Ratio ◽  
Nephelium Lappaceum ◽  
Mean Particle Diameter

The aim of the present work was to extract the seed fat of Rambutan (Nephelium lappaceum L.) for developing nanostructured lipid carriers. Effect of material: solvent ratio and material size time on fat content were investigated. Nanostructured lipid carriers were prepared by melt-emulsification technique. Stearic acid (SA) and the rambutan seed fat (RF) was used as solid and liquid lipid, respectively. Surfactant was Tween 20 as well as Vitamin E was entrapment chemical. Effect of surfactant concentration on formation and stability of solid lipid nanoparticles (SLN) was investigated. At higher surfactant concentrations, NLC had smaller particle size and better stability of nanoparticles. At the optimal concentration of Tween 20 (5% w/w), NLC had a mean particle diameter of 139.43 ± 1.15 nm and a polydispersity index of 0.165 ± 0.017. Zeta potential was above 30 mV.

Sign in / Sign up

Export Citation Format

Share Document