scholarly journals Activation of sub-3 nm organic particles in the particle size magnifier using humid and dry conditions

2022 ◽  
pp. 105945
Author(s):  
B. Rörup ◽  
W. Scholz ◽  
L. Dada ◽  
M. Leiminger ◽  
R. Baalbaki ◽  
...  
Keyword(s):  
Particle Size ◽  
Dry Conditions ◽  
Organic Particles

MECHANICAL PROPERTIES OF POLYMER COMPOSITES BASED ON BIOPARTICLES (JATROPHA CURCAS L.)

2015 ◽  
Vol 76 (3) ◽  
Author(s):  
Petr VALÁŠEK
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Polymer Composites ◽  
Renewable Resources ◽  
Jatropha Curcas ◽  
Epoxy Resins ◽  
Polymer Materials ◽  
Jatropha Curcas L ◽  
Composite Systems ◽  
Organic Particles

Composites are materials which synergically combine properties of each phase – matrix and filler. Polymer materials can be used as matrix while inorganic and organic particles can be used as fillers. Composite systems based on renewable resources can be designed as an interesting material for engineering. This paper describes on the tribological and other mechanical properties of biocomposites based on polymer resins and microparticles - seed cakes, which were obtained from seeds of the plant Jatropha Curcas L. during pressing. The particle size obtained was 573 µm.The results confirmed that the epoxy and polyurethane resins were capable of forming which corresponds to the interaction with the organic particles prepared from the seeds of Jatropha Curcas L. The presence of particles however, changed the mechanical properties of the resins. In the case of epoxy resins and polyurethane (Sika Force 7723), the hardness according to Shore D identically decreased with a maximum of 1.9. Abrasion resistance decreased due to the presence of particles of 0.0393 cm3 for Glue Epox Rapid, 0.0449 cm3 for Epoxy 1200/324 and 0.0567 cm3 for Sika Force 7723.

scholarly journals Comparing SOA volatility distributions derived from isothermal SOA particle evaporation data and FIGAERO-CIMS measurements

2019 ◽  
Author(s):  
Olli-Pekka Tikkanen ◽  
Angela Buchholz ◽  
Arttu Ylisirniö ◽  
Siegfried Schobesberger ◽  
Annele Virtanen ◽  
...  
Keyword(s):  
Particle Size ◽  
Organic Compounds ◽  
Thermal Desorption ◽  
Process Modelling ◽  
Reasonable Assumption ◽  
Ionization Mass ◽  
Oxidation Condition ◽  
Size Change ◽  
Dry Conditions ◽  
Modelling Techniques

Abstract. The volatility distribution of the organic compounds present in SOA at different conditions is a key quantity that has to be captured in order to describe SOA dynamics accurately. The development of the filter inlet for gases and aerosols (FIGAERO) and its coupling to chemical ionization mass spectrometer (CIMS) has enabled near simultaneous sampling of gas and particle phases of secondary organic aerosol (SOA) through thermal desorption of the particles. The thermal desorption data has recently been shown to be interpretable as a volatility distribution with the use of positive matrix factorization (PMF) method. Similarly, volatility distribution can be inferred from isothermal particle evaporation experiments, when the particle size change measurements are analyzed with process modelling techniques. In this study we compare the volatility distributions that are retrieved from FIGAERO-CIMS and particle size change measurements during isothermal particle evaporation with process modelling techniques. We compare the volatility distributions at two different relative humidity (RH) and two oxidation condition. At high RH conditions, where particles are in a liquid state, we show that the volatility distributions derived the two ways are comparable within reasonable assumption of uncertainty in the effective saturation mass concentrations that are derived from FIGAERO-CIMS data. At dry conditions we demonstrate the volatility distributions are comparable in one oxidation condition and in the other oxidation condition the volatility distribution derived from the PMF analysis shows considerably more high volatility matter than the volatility distribution inferred from particle size change measurements. We also show that the Vogel-Tammann-Fulcher equation together with a recent glass transition temperature parametrization for organic compounds and PMF derived volatility distribution estimate are consistent with the observed isothermal evaporation under dry conditions within the reported uncertainties. We conclude that the FIGAERO-CIMS measurements analyzed with the PMF method are a promising method for inferring organic compounds' volatility distribution, but care has to be taken when the PMF factors are interpreted. Future process modelling studies about SOA dynamics and properties could benefit from simultaneous FIGAERO-CIMS measurements.

scholarly journals A discrete interaction numerical model for coagulation and fragmentation of marine detritic particulate matter (Coagfrag v.1)

2021 ◽  
Vol 14 (7) ◽  
pp. 4535-4554
Author(s):  
Gwenaëlle Gremion ◽  
Louis-Philippe Nadeau ◽  
Christiane Dufresne ◽  
Irene R. Schloss ◽  
Philippe Archambault ◽  
...  
Keyword(s):  
Particle Size ◽  
General Circulation ◽  
Size Range ◽  
Circulation Model ◽  
Mass Conservation ◽  
Ocean General Circulation Model ◽  
Global Constraints ◽  
Size Spectrum ◽  
Particle Sizes ◽  
Organic Particles

Abstract. A simplified model, representing the dynamics of marine organic particles in a given size range experiencing coagulation and fragmentation reactions, is developed. The framework is based on a discrete size spectrum on which reactions act to exchange properties between different particle sizes. The reactions are prescribed according to triplet interactions. Coagulation combines two particle sizes to yield a third one, while fragmentation breaks a given particle size into two (i.e. the inverse of the coagulation reaction). The complete set of reactions is given by all the permutations of two particle sizes associated with a third one. Since, by design, some reactions yield particle sizes that are outside the resolved size range of the spectrum, a closure is developed to take into account this unresolved range and satisfy global constraints such as mass conservation. In order to minimize the number of tracers required to apply this model to an ocean general circulation model, focus is placed on the robustness of the model to the particle size resolution. Thus, numerical experiments were designed to study the dependence of the results on (i) the number of particle size bins used to discretize a given size range (i.e. the resolution) and (ii) the type of discretization (i.e. linear vs. nonlinear). The results demonstrate that in a linearly size-discretized configuration, the model is independent of the resolution. However, important biases are observed in a nonlinear discretization. A first attempt to mitigate the effect of nonlinearity of the size spectrum is then presented and shows significant improvement in reducing the observed biases.

scholarly journals Comparing secondary organic aerosol (SOA) volatility distributions derived from isothermal SOA particle evaporation data and FIGAERO–CIMS measurements

2020 ◽  
Vol 20 (17) ◽  
pp. 10441-10458 ◽  
Author(s):  
Olli-Pekka Tikkanen ◽  
Angela Buchholz ◽  
Arttu Ylisirniö ◽  
Siegfried Schobesberger ◽  
Annele Virtanen ◽  
...  
Keyword(s):  
Particle Size ◽  
Organic Compounds ◽  
Thermal Desorption ◽  
Process Modeling ◽  
Secondary Organic Aerosol ◽  
Organic Aerosol ◽  
Oxidation Condition ◽  
Size Change ◽  
Modeling Techniques ◽  
Dry Conditions

Abstract. The volatility distribution of the organic compounds present in secondary organic aerosol (SOA) at different conditions is a key quantity that has to be captured in order to describe SOA dynamics accurately. The development of the Filter Inlet for Gases and AEROsols (FIGAERO) and its coupling to a chemical ionization mass spectrometer (CIMS; collectively FIGAERO–CIMS) has enabled near-simultaneous sampling of the gas and particle phases of SOA through thermal desorption of the particles. The thermal desorption data have been recently shown to be interpretable as a volatility distribution with the use of the positive matrix factorization (PMF) method. Similarly, volatility distributions can be inferred from isothermal particle evaporation experiments when the particle size change measurements are analyzed with process-modeling techniques. In this study, we compare the volatility distributions that are retrieved from FIGAERO–CIMS and particle size change measurements during isothermal particle evaporation with process-modeling techniques. We compare the volatility distributions at two different relative humidities (RHs) and two oxidation conditions. In high-RH conditions, where particles are in a liquid state, we show that the volatility distributions derived via the two ways are similar within a reasonable assumption of uncertainty in the effective saturation mass concentrations that are derived from FIGAERO–CIMS data. In dry conditions, we demonstrate that the volatility distributions are comparable in one oxidation condition, and in the other oxidation condition, the volatility distribution derived from the PMF analysis shows considerably more high-volatility matter than the volatility distribution inferred from particle size change measurements. We also show that the Vogel–Tammann–Fulcher equation together with a recent glass transition temperature parametrization for organic compounds and PMF-derived volatility distribution estimates are consistent with the observed isothermal evaporation under dry conditions within the reported uncertainties. We conclude that the FIGAERO–CIMS measurements analyzed with the PMF method are a promising method for inferring the volatility distribution of organic compounds, but care has to be taken when the PMF factors are analyzed. Future process-modeling studies about SOA dynamics and properties could benefit from simultaneous FIGAERO–CIMS measurements.

FATE OF SILTS AND CLAY FROM RIVER AND ITS CONTRIBUTION TO TRANSPARENCY

2017 ◽  
Author(s):  
Tetsuji Okuda ◽  
Tetsuji Okuda ◽  
Satoshi Sekitou ◽  
Satoshi Sekitou ◽  
Akira Umehara ◽  
...  
Keyword(s):  
Particle Size ◽  
Silica Particle ◽  
Laboratory Experiments ◽  
Linear Regression Analysis ◽  
Light Attenuation ◽  
Euphotic Zone ◽  
Multiple Linear Regression Analysis ◽  
Inorganic Particle ◽  
Osaka Bay ◽  
Organic Particles

Phytoplankton plays a key role as primary producer, forming the base of marine food webs. Knowledge in relation to permeability of light in water is important for the understanding of phytoplankton growth in the euphotic zone. In this study, we conducted laboratory experiments in relation to light attenuation using inorganic particle (silica particle) and field investigations in Osaka Bay. There was a positive correlation between the concentrations of the silica particle and integral values of the absorbance at photosynthetic active radiation (PAR: wavelength 400-700 nm) in the laboratory experiments. The highest integral value of the absorbance at PAR was observed for the particle size of 1.0 μm. In Osaka Bay, high contribution of the inorganic particle to light attenuation was observed compared to the organic particles. Multiple linear regression analysis using the particle size and the amount of total suspended solids (TSS: consisting of three component fractions; organic/inorganic tripton and phytoplanktons) showed that the particle size was an essential factor controlling the light attenuation in the coastal sea.

scholarly journals Influence of the Feed Moisture, Rotor Speed, and Blades Gap on the Performances of a Biomass Pulverization Technology

2014 ◽  
Vol 2014 ◽  
pp. 1-5
Author(s):  
Siyi Luo ◽  
Yangmin Zhou ◽  
Chuijie Yi ◽  
Yin Luo ◽  
Jie Fu
Keyword(s):  
Particle Size ◽  
Energy Consumption ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Specific Energy ◽  
Rotor Speed ◽  
Operational Parameters ◽  
Product Particle ◽  
Dry Conditions ◽  
Feed Moisture

Recently, a novel biomass pulverization technology was proposed by our group. In this paper, further detailed studies of this technology were carried out. The effects of feed moisture and crusher operational parameters (rotor speed and blades gap) on product particle size distribution and energy consumption were investigated. The results showed that higher rotor speed and smaller blades gap could improve the hit probability between blades and materials and enhance the impacting and grinding effects to generate finer products, however, resulting in the increase of energy consumption. Under dry conditions finer particles were much more easily achieved, and there was a tendency for the specific energy to increase with increasing feed moisture. Therefore, it is necessary for the raw biomass material to be dried before pulverization.

Effect on Drying Conditions on Amorphous Calcium Phosphate

2014 ◽  
Vol 631 ◽  
pp. 99-103 ◽  
Author(s):  
Agnese Brangule ◽  
Kārlis Gross
Keyword(s):  
Particle Size ◽  
Calcium Phosphate ◽  
Amorphous Calcium Phosphate ◽  
Intermediate Phase ◽  
Calcium Phosphates ◽  
Ftir Spectra ◽  
The Body ◽  
Drying Methods ◽  
Dry Conditions ◽  
Drying Conditions

Amorphous calcium phosphate (ACP) plays an important role in the body and can be used as an intermediate phase for forming calcium phosphates. All ACPs are thermodynamically unstable compounds, unless stored in dry conditions or at low temperature (-18oC), and spontaneously undergo transformation to crystalline calcium phosphates (CaP). This work will investigate the influence of drying on the stability of ACP. ACPs powders were prepared by wet synthesis; mixing solution made of Ca (NO3)2∙4H2O and 30% ammonia with (NH4)2HPO4 and (NH4)2CO3 solution at room temperature. The suspension was stirred, filtered and washed several times with deionized water containing ammonia. ACP samples were dried at different conditions and with different drying agents (DA). XRD and FTIR spectra showed poorly crystallinity powders after drying. Some FTIR spectra indicated residual organic compounds from drying. The Rietveld’s method and Schrrer’s relationship estimated the particle size (0.5 – 20 nm) of ACP. Thermogravimetry (TG) revealed that the moisture (7% – 25%) is released upon drying, and the drying agents have no significant effect on. The drying methods are ordered to show which the most effective for removing moisture. By changing the drying conditions, it is a possible to obtain poorly crystalline ACPs with different particle size and moisture content.

scholarly journals Enhanced survival of spray-dried microencapsulated Lactobacillus casei in the presence of mix-prebiotic

2015 ◽  
Vol 18 (2) ◽  
pp. 65-74
Author(s):  
Dong My Lieu ◽  
Hoai Van Bui ◽  
Huong Thuy Nguyen
Keyword(s):  
Particle Size ◽  
Whey Protein ◽  
Lactobacillus Casei ◽  
Viable Cell ◽  
Gastric Fluid ◽  
Wall Material ◽  
Simulated Gastric Fluid ◽  
Spray Dry ◽  
Cell Counts ◽  
Dry Conditions

In this study, the effect of Galactooligosaccharide (GOS) (0% và 2% w/v) on microencapsulated L.casei in whey protein 10% (w/v) and maltodextrin 5% (w/v) by spray dry method were investigated. The physical characterization included analysis of morphology, particle size. The viable cell counts of the microcapsule were determined during storage for 50 days at 10oC and in simulated gastric fluid (SGF) and intestinal fluid (SIF). All microcapsules with (WMG sample) or without GOS (WM sample) in this study showed similar morphology and particle size, between 3 to 11µm. There no differences between WMG and WM sample in cell viability were observed. For spray dry conditions tested in this work the cell viable yield with WM sample about 86.14% whereas for WMG sample about 86.78%. The viability of the microcapsules in WMG and WM were reduced about 0.44 and 0.63 log(CFU/g), respectively and remained > 6 log(CFU/g) after 2 hour in SGF or 4 hour in SIF incubating. Microcapsules made by spray dry method with whey protein 10% (w/v) and maltodextrin 5% (w/v) as encapsulating which enhancing L.casei survival, maltodextrin’s role not only as a wall material in microencapsulation but also as a prebiotic potential, eventually leading to added GOS was not necessary.

scholarly journals A discrete interaction numerical model for coagulation and fragmentation of marine detritic particulate matter

2021 ◽  
Author(s):  
Gwenaëlle Gremion ◽  
Louis-Philippe Nadeau ◽  
Christiane Dufresne ◽  
Irene R. Schloss ◽  
Philippe Archambault ◽  
...  
Keyword(s):  
Particle Size ◽  
General Circulation ◽  
Size Range ◽  
Circulation Model ◽  
Mass Conservation ◽  
Ocean General Circulation Model ◽  
Global Constraints ◽  
Size Spectrum ◽  
Particle Sizes ◽  
Organic Particles

Abstract. A simplified model, representing the dynamics of marine organic particles in a given size range experiencing coagulation and fragmentation reactions is developed. The framework is based on a discrete size spectrum on which reactions act to exchange properties between different particle sizes. The reactions are prescribed according to triplets interactions. Coagulation combines two particle sizes to yield a third one, while fragmentation breaks a given particle size into two (i.e. the inverse of the coagulation reaction). The complete set of reactions is given by all the permutations of two particle sizes associated with a third one. Since, by design, some reactions yield particle sizes that are outside the resolved size range of the spectrum, a closure is developed to take into account this unresolved range and satisfy global constraints such as mass conservation. In order to minimize the number of tracers required to apply this model to an Ocean General Circulation Model focus is placed on the robustness of the model to the particle size resolution. Thus, numerical experiments were designed to study the dependence of the results on i) the number of particle size bins used to discretize a given size range (i.e. the resolution) and ii) the type of discretization (i.e. linear vs nonlinear). The results demonstrate that in a linearly size discretized configuration, the model is independent of the resolution. However, important biases are observed in a nonlinear discretization. A first attempt to mitigate the effect of nonlinearity of the size spectrum is then presented and shows significant improvement in reducing the observed biases.

scholarly journals The effect of particle shape on discharge and clogging

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ahmed Hafez ◽  
Qi Liu ◽  
Thomas Finkbeiner ◽  
Raed A. Alouhali ◽  
Timothy E. Moellendick ◽  
...  
Keyword(s):  
Particle Size ◽  
Energy Resource ◽  
Size Ratio ◽  
Spherical Particles ◽  
Particle Interactions ◽  
Face To Face ◽  
Particle Size Ratio ◽  
Dry Conditions ◽  
Large Orifice ◽  
Flow Variables

AbstractGranular flow is common across different fields from energy resource recovery and mineral processing to grain transport and traffic flow. Migrating particles may jam and form arches that span constrictions and hinder particle flow. Most studies have investigated the migration and clogging of spherical particles, however, natural particles are rarely spherical, but exhibit eccentricity, angularity and roughness. New experiments explore the discharge of cubes, 2D crosses, 3D crosses and spheres under dry conditions and during particle-laden fluid flow. Variables include orifice-to-particle size ratio and solidity. Cubes and 3D crosses are the most prone to clogging because of their ability to interlock or the development of face-to-face contacts that can resist torque and enhance bridging. Spheres arriving to the orifice must be correctly positioned to create stable bridges, while flat 2D crosses orient their longest axes in the direction of flowlines across the orifice and favor flow. Intermittent clogging causes kinetic retardation in particle-laden flow even in the absence of inertial effects; the gradual increase in the local particle solidity above the constriction enhances particle interactions and the probability of clogging. The discharge volume before clogging is a Poisson process for small orifice-to-particle size ratio; however, the clogging probability becomes history-dependent for non-spherical particles at large orifice-to-particle size ratio and high solidities, i.e., when particle–particle interactions and interlocking gain significance.

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