Obtaining and investigation of a finely dispersed fraction of granulated blast-furnace slags for use as components of clinker-free binders

2021 ◽  
pp. 56-63
Author(s):  
B. B. Khaidarov ◽  
D. S. Suvorov ◽  
D. V. Lysov ◽  
A. K. Abramov ◽  
G. G. Luchnikova ◽  
...  
Keyword(s):  
Particle Size ◽  
Blast Furnace ◽  
Physicochemical Characteristics ◽  
Air Classification ◽  
Granulated Slag ◽  
Comprehensive Study

A method for obtaining a finely dispersed fraction of ground blast-furnace granulated slag has been developed. The resulting material with the introduction of an alkaline additive can be offered as an alternative to foreign analogous fine-dispersed mineral binders, an example of which can be microcement. A comprehensive study of granular slags of two metallurgical plants was carried out, the physicochemical characteristics of materials were determined. The possibility of obtaining a fraction of ground granular slag with a particle size of no more than 16 microns using vortex electromagnetic homogenization and subsequent air classification is shown.

scholarly journals Encapsulation of Berberis vulgaris Anthocyanins into Nanoliposome Composed of Rapeseed Lecithin: A Comprehensive Study on Physicochemical Characteristics and Biocompatibility

Foods ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 492
Author(s):  
Mina Homayoonfal ◽  
Seyed Mohammad Mousavi ◽  
Hossein Kiani ◽  
Gholamreza Askari ◽  
Stephane Desobry ◽  
...  
Keyword(s):  
Particle Size ◽  
Zeta Potential ◽  
Hydrophobic Interactions ◽  
Hydrocarbon Chain ◽  
Physicochemical Characteristics ◽  
Narrow Particle Size Distribution ◽  
In Vitro Biocompatibility ◽  
Comprehensive Study ◽  
Rapeseed Lecithin

In the present study, nanoliposomes composed of rapeseed lecithin were used for the encapsulation of anthocyanin compounds (AC). The nanoliposomes were prepared using hydration and ultrasound combined method, and the effect of AC concentration (4.5, 6.75, 9% w/w) on the characteristics of nanoliposomes including particle size, polydispersity index (PDI), zeta potential, and the encapsulation efficiency (EE) of nanoliposomes with and without AC were studied. The results suggested the fabricated nanoliposomes had a size range of 141–196 nm, negative zeta potential and narrow particle size distribution. Further, the samples containing 9% extract had the maximum EE (43%). The results showed elevation of AC concentration resulted in increased particle size, PDI, EE, and surface charge of nanoparticles. The presence of AC extract led to diminished membrane fluidity through the hydrophobic interactions with the hydrocarbon chain of fatty acids. TEM images suggested that the nanoliposomes were nearly spherical and the AC caused their improved sphericity. Further, in vitro biocompatibility tests for human mesenchymal (MSC) and fibroblast (FBL) cells indicated nanoparticles were not toxic. Specifically, the best formulations with the maximum compatibility and bioavailability for MSC and FBL cells were AC-loaded nanoliposomes with concentrations of 0.5 mL/mg and 10.3 mL/µg and, respectively.

scholarly journals Translating the fabrication of protein-loaded poly(lactic-co-glycolic acid) nanoparticles from bench to scale-independent production using microfluidics

2020 ◽  
Vol 10 (3) ◽  
pp. 582-593 ◽  
Author(s):  
Carla B. Roces ◽  
Dennis Christensen ◽  
Yvonne Perrie
Keyword(s):  
Particle Size ◽  
Glycolic Acid ◽  
Polymeric Nanoparticles ◽  
Physicochemical Characteristics ◽  
European Medicines Agency ◽  
Protein Encapsulation ◽  
Human Use ◽  
Rate Ratios ◽  
The Impact ◽  
Process Controls

AbstractIn the formulation of nanoparticles, poly(lactic-co-glycolic acid) (PLGA) is commonly employed due to its Food and Drug Administration and European Medicines Agency approval for human use, its ability to encapsulate a variety of moieties, its biocompatibility and biodegradability and its ability to offer a range of controlled release profiles. Common methods for the production of PLGA particles often adopt harsh solvents, surfactants/stabilisers and in general are multi-step and time-consuming processes. This limits the translation of these drug delivery systems from bench to bedside. To address this, we have applied microfluidic processes to develop a scale-independent platform for the manufacture, purification and monitoring of nanoparticles. Thereby, the influence of various microfluidic parameters on the physicochemical characteristics of the empty and the protein-loaded PLGA particles was evaluated in combination with the copolymer employed (PLGA 85:15, 75:25 or 50:50) and the type of protein loaded. Using this rapid production process, emulsifying/stabilising agents (such as polyvinyl alcohol) are not required. We also incorporate in-line purification systems and at-line particle size monitoring. Our results demonstrate the microfluidic control parameters that can be adopted to control particle size and the impact of PLGA copolymer type on the characteristics of the produced particles. With these nanoparticles, protein encapsulation efficiency varies from 8 to 50% and is controlled by the copolymer of choice and the production parameters employed; higher flow rates, combined with medium flow rate ratios (3:1), should be adopted to promote higher protein loading (% wt/wt). In conclusion, herein, we outline the process controls for the fabrication of PLGA polymeric nanoparticles incorporating proteins in a rapid and scalable manufacturing process.

scholarly journals Changes in suspension properties of structural modified montmorillonites

Cerâmica ◽  
2001 ◽  
Vol 47 (301) ◽  
pp. 4-8 ◽  
Author(s):  
C. Volzone ◽  
L. B. Garrido
Keyword(s):  
Particle Size ◽  
Structural Disorder ◽  
Physicochemical Characteristics ◽  
Exchange Capacity ◽  
X Ray Diffraction ◽  
Flow Properties ◽  
Flow Curves ◽  
Structural Modifications ◽  
Fine Particle Size ◽  
Cationic Exchange

Rheological changes were found in smectite (Wyoming- and Cheto-type montmorillonites) suspensions after structural modifications. The effect of the particle size and Na+ exchange on the flow curves of 6% wt/wt suspensions of smectites with and without Na2CO3 were examined. Mineralogical, structural and physicochemical characteristics were studied by X-ray diffraction (XRD), infrared spectroscopy (IR), cationic exchange capacity (CEC), Mg2+, Al3+ determinations, particle size distribution and swelling index (SI). Grinding in an oscillating mill modified the particle sizes. The montmorillonite grain size and the structural disorder increased after larger grinding times. The grinding treatment modified the apparent viscosity and the yield stress of the montmorillonite suspensions. The homoionic Na Cheto-type montmorillonite with fine particle size (obtained by grinding) increased the flow properties. Nevertheless, rheological properties were lower than those of suspensions of the Wyoming-type montmorillonite. Montmorillonite-types reacted differently with Na2CO3 additions and this behavior may be related to their structural composition. The Na2CO3 activation improved the flow properties of the original Wyoming-type montmorillonite and after 30 s grinding.

Blast furnace granulated slag in the production of building ceramics

1990 ◽  
Vol 47 (6) ◽  
pp. 228-230 ◽  
Author(s):  
V. A. Osipov ◽  
Z. G. Timofeeva ◽  
M. N. Kurbatskii ◽  
P. V. Mironova ◽  
F. F. Ocheretnyuk
Keyword(s):  
Blast Furnace ◽  
Granulated Slag

scholarly journals Fabrication of nanoemulsion system containing chloramphenicol and palm kernel oil esters for parenteral treatment of meningitis

2019 ◽  
Vol 10 (SPL1) ◽  
Author(s):  
Siti Hajar Musa ◽  
Ahmad Fuad Shamsuddin ◽  
Emilia Abd Malek ◽  
Hamidon Basri ◽  
Mahiran Basri ◽  
...  
Keyword(s):  
Particle Size ◽  
Palm Kernel ◽  
Physicochemical Characteristics ◽  
Intravenous Route ◽  
Particle Sizes ◽  
Streptococcus Pneumonia ◽  
Current Medication ◽  
The Family ◽  
Toxicity Analysis ◽  
The Brain

Meningitis is a disease caused by a bacterial infection in the brain. Streptococcus pneumonia is the most common causative agent for meningitis disease. Chloramphenicol used to be a drug used for the treatment of meningitis. Current medication in treating meningitis is using the family of cephalosporin drugs. However, due to the drug-resistant problem, this family of a drug is no longer efficient towards the meningitis bacteria. Thus, the use of chloramphenicol has caught back the attention in treating meningitis disease. Chloramphenicol is claimed to be toxic towards human cells since the higher dosage is needed per injection for every treatment. This is corresponding to the poor delivery method of this hydrophobic drug. Nanoemulsion is believed to be the best option in transporting chloramphenicol to the brain by the intravenous route. A good combination of oil mixed with a surfactant mixture led to the formation of formulation with small particle sizes with low PDI values. Optimization of nanoemulsion's composition using Response Surface Methodology (RSM) suggested that the best amount of oil, lecithin, and glycerol were 4%, 2.5%, and 2.25%, respectively. The optimized formulation was then modified due to the instability and insufficient osmolality value of the formulation. The physicochemical characteristics (particle size, PDI, zeta potential, osmolality, viscosity, and pH) of the formulation successfully fulfilled the requirement for parenteral application. Toxicity analysis showed that chloramphenicol encapsulated nanoemulsion system was much safer compared to the standard chloramphenicol. Storage of the chloramphenicol-loaded nanoemulsion at 4°C showed good stability for 3 months with no significant changes on the particle size.  

scholarly journals Physicochemical Characterization of a Dental Eggshell Powder Abrasive Material

2017 ◽  
Vol 15 (4) ◽  
pp. e341-e346 ◽  
Author(s):  
Stanley C. Onwubu ◽  
Anisa Vahed ◽  
Shalini Singh ◽  
Krishnan M. Kanny
Keyword(s):  
Surface Roughness ◽  
Particle Size ◽  
Ftir Spectroscopy ◽  
Physicochemical Characterization ◽  
Xrd Analysis ◽  
Physicochemical Characteristics ◽  
Threshold Limit Value ◽  
Abrasive Material ◽  
Limit Value ◽  
Transmission Electron

Background This study aimed to determine the physicochemical characteristics of an eggshell-based dental abrasive material. Methods The eggshell powder abrasive material (EPAM) was synthesized by ball milling eggshell powder and surfactants. Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM) and a laser diffraction particle size analyzer (PSA) were used to characterize EPAM. In addition, the abrasive characteristics of EPAM were evaluated by comparison using poly(methyl methacrylate) (PMMA) resins. Surface roughness (Ra) was measured using a profilometer. Results The FTIR spectroscopy and XRD analysis confirmed that the carbonate product was primarily calcite (97.3%) with traces of graphite 2H (1.3%) and thenardite (1.4%). The TEM imagery revealed irregular particles in EPAM. The PSA analysis of the particle size distribution showed EPAM to be a superfine powder (0.3 μm to 50 nm). In addition, the 50-nm EPAM (Ra = 0.04 μm) measured the lowest Ra value when compared with pumice (Ra = 0.08 μm). Conclusions The salient features of this study indicate that EPAM can naturally replace calcite, which is generally mined and used as a dental abrasive material. In addition, and regarding the abrasive characteristics of EPAM in reducing the surface roughness of PMMA resin specimens, this study conclusively showed that EPAM effectively reduces the surface roughness below the threshold limit value of 0.2 μm. Potentially, EPAM could reduce waste disposal problems while enabling an economic benefit from using eggshell waste material.

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