scholarly journals Production of L-Leucine Nanoparticles under Various Conditions Using an Aerosol Flow Reactor Method

2008 ◽  
Vol 2008 ◽  
pp. 1-9 ◽  
Author(s):  
Anna Lähde ◽  
Janne Raula ◽  
Esko I. Kauppinen
Keyword(s):  
Vapour Deposition ◽  
Flow Reactor ◽  
Geometric Mean ◽  
Particle Morphology ◽  
Particle Method ◽  
Vapour Phase ◽  
Spherical Particles ◽  
Subsequent Growth ◽  
Aerosol Flow ◽  
Size Distribution Of Particles

We have studied the formation of L-leucine nanoparticles under various conditions using an aerosol flow reactor method. Temperatures and L-leucine concentrations for the experiments were selected to vary the saturation conditions for L-leucine in the reactor. In the two extreme cases, L-leucine is either in (i) the condensed phase (110°C) or completely in (ii) the vapour phase (200°C) for all concentrations; (iii) at the intermediate temperature (150°C), the extent of evaporation of L-leucine depends notably on the concentration, and thus partial evaporation and production of residual particles are expected. The size distribution of particles and the particle morphology varied according to formation mechanism with the geometric mean diameter of the particles between 30 nm and 210 nm. Hollow, spherical particles were obtained with the droplet-to-particle method without vaporisation of L-leucine; whereas leafy-looking particles were produced by homogeneous nucleation of supersaturated L-leucine vapour and subsequent growth by heterogeneous vapour deposition.

Characterization of Particles Synthesized by Aerosol Processes for Various Pb:Si Molar Feed Ratios

1995 ◽  
Vol 400 ◽  
Author(s):  
Timothy M. Owens ◽  
Pratim Biswas
Keyword(s):  
Flow Reactor ◽  
Particle Morphology ◽  
High Specific Surface Area ◽  
Spherical Particles ◽  
Maximum Temperature ◽  
Lead Silicate ◽  
Lead Compounds ◽  
Large Agglomerate ◽  
Primary Particles

AbstractA detailed characterization was performed of the particles produced under various Pb:Si molar feed ratios in a flow reactor at a maximum temperature of 1000 °C. The silica particles formed in the high temperature region coagulated and only partially coalesced to form large agglomerate structures of high specific surface area. For a lead only feed, the resulting particles were hydrocerussite with small but detectable amounts of massicot. As the silica precursor was inlet in excess amounts (Pb:Si ≤ 1:12), the crystalline lead compounds disappeared and amorphous lead-silica complexes predominated. The particle morphology also changed from cylindrical, polygonal and spherical shapes to large agglomerate structures composed of several size modes of primary particles. At Pb:Si molar feed ratios of 1:12 and 1:29, the particles making up the chain-like agglomerate structure were primarily spherical with larger lead silicate spherical particles (≈ 0.5 μm) attached to the agglomerate. The lead was found to be distributed throughout the large agglomerate structures.

High-Throughput Synthesis of Lignin Particles (∼30 nm to ∼2 μm) via Aerosol Flow Reactor: Size Fractionation and Utilization in Pickering Emulsions

2016 ◽  
Vol 8 (35) ◽  
pp. 23302-23310 ◽  
Author(s):  
Mariko Ago ◽  
Siqi Huan ◽  
Maryam Borghei ◽  
Janne Raula ◽  
Esko I. Kauppinen ◽  
...  
Keyword(s):  
High Throughput ◽  
Flow Reactor ◽  
Pickering Emulsions ◽  
Size Fractionation ◽  
Aerosol Flow

Aerosol Flow Reactor Method for the Synthesis of Multicomponent Drug Nano- and Microparticles

2007 ◽  
pp. 111-128
Author(s):  
Janne Raula ◽  
Hannele Eerikäinen ◽  
Anna Lähde ◽  
Esko I. Kauppinen
Keyword(s):  
Flow Reactor ◽  
Aerosol Flow

scholarly journals Use of Electrosprayed Agave Fructans as Nanoencapsulating Hydrocolloids for Bioactives

Nanomaterials ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 868 ◽  
Author(s):  
Jorge Ramos-Hernández ◽  
Juan Ragazzo-Sánchez ◽  
Montserrat Calderón-Santoyo ◽  
Rosa Ortiz-Basurto ◽  
Cristina Prieto ◽  
...  
Keyword(s):  
Uv Light ◽  
Particle Morphology ◽  
Bioactive Compound ◽  
Processing Parameters ◽  
Degree Of Polymerization ◽  
Spherical Particles ◽  
Sem Images ◽  
High Degree ◽  
Thermal Stability Of ◽  
Β Carotene

High degree of polymerization Agave fructans (HDPAF) are presented as a novel encapsulating material. Electrospraying coating (EC) was selected as the encapsulation technique and β-carotene as the model bioactive compound. For direct electrospraying, two encapsulation methodologies (solution and emulsion) were proposed to find the formulation which provided a suitable particle morphology and an adequate concentration of β-carotene encapsulated in the particles to provide a protective effect of β-carotene by the nanocapsules. Scanning electron microscopy (SEM) images showed spherical particles with sizes ranging from 440 nm to 880 nm depending on the concentration of HDPAF and processing parameters. FTIR analysis confirmed the interaction and encapsulation of β-carotene with HDPAF. The thermal stability of β-carotene encapsulated in HDPAF was evidenced by thermogravimetric analysis (TGA). The study showed that β-carotene encapsulated in HDPAF by the EC method remained stable for up to 50 h of exposure to ultraviolet (UV) light. Therefore, HDPAF is a viable option to formulate nanocapsules as a new encapsulating material. In addition, EC allowed for increases in the ratio of β-carotene:polymer, as well as its photostability.

Modeling the formation of boron carbide particles in an aerosol flow reactor

AIChE Journal ◽  
1992 ◽  
Vol 38 (11) ◽  
pp. 1685-1692 ◽  
Author(s):  
Yun Xiong ◽  
Sotiris E. Pratsinis ◽  
Alan W. Weimer
Keyword(s):  
Boron Carbide ◽  
Flow Reactor ◽  
Aerosol Flow ◽  
Carbide Particles

An investigation of a fluidized bed solids feeder for an aerosol flow reactor

2010 ◽  
Vol 199 (1) ◽  
pp. 70-76 ◽  
Author(s):  
Todd M. Francis ◽  
Peter B. Kreider ◽  
Paul R. Lichty ◽  
Alan W. Weimer
Keyword(s):  
Fluidized Bed ◽  
Flow Reactor ◽  
Aerosol Flow

One-step vapour phase growth of two-dimensional formamidinium-based perovskite and its hot carrier dynamics

2020 ◽  
Vol 22 (37) ◽  
pp. 21512-21519
Author(s):  
Ufuk Erkılıç ◽  
Hyun Goo Ji ◽  
Eiji Nishibori ◽  
Hiroki Ago
Keyword(s):  
Vapour Deposition ◽  
Vapour Phase ◽  
Carrier Dynamics ◽  
Two Dimensional ◽  
Deposition Method ◽  
Phase Growth ◽  
Hot Carrier ◽  
One Step

Square-shaped layered FA2PbI4 perovskite crystals were prepared using a one-step vapour deposition method, and the hot carrier dynamics of these crystals was studied.

Vapor phase synthesis of Al-doped titania powders

1994 ◽  
Vol 9 (5) ◽  
pp. 1241-1249 ◽  
Author(s):  
Kamal M. Akhtar ◽  
Sotiris E. Pratsinis ◽  
Sebastian V.R. Mastrangelo
Keyword(s):  
Vapor Phase ◽  
Flow Reactor ◽  
Particle Surface ◽  
Particle Morphology ◽  
High Concentration ◽  
Phase Synthesis ◽  
Transmission Electron ◽  
Significant Enrichment ◽  
Vapor Phase Synthesis ◽  
Doped Titania

The role of aluminum as dopant in gas phase synthesis of titania powders was experimentally investigated in an aerosol flow reactor between 1300 and 1700 K. Titania was produced by vapor phase oxidation of titanium tetrachloride in the presence of dopant aluminum trichloride vapor. The presence of aluminum altered the particle morphology from polyhedral to irregular crystals. Energy dispersive analysis and transmission electron microscopy indicated that the powders were mixtures of crystalline titania and amorphous alumina. Analysis by XPS indicated significant enrichment of aluminum on the particle surface. Some aluminum titanate (up to 17% by volume) was formed at 1700 K when a high concentration of AlCl3 was used (AlCl3/TiCl4 ≥ 0.07). Measurements of lattice parameters by x-ray diffraction indicated that aluminum formed a solid solution in titania. While titania synthesized in the absence of aluminum was about 90% anatase, the introduction of aluminum resulted in pure rutile at AlCl3/TiCl4 = 0.07. The effects of aluminum on titania phase composition and morphology are explained by the creation of oxygen vacancies in the titania crystallites and by the enhancement of the sintring rate of titania grains.

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