Formation Of Solid Particles Research Articles

Caramelized white chocolate: effects of production process on quality parameters

The impact of different temperatures (110–120 °C) and times (30–120 min) on rheological properties, aroma components, color, browning index, and sensory characteristics of the caramelized white chocolate was examined. Ostwald de Waele model best fitted to flow behavior of the chocolates. The dependency of viscosity on temperature was modeled by the Arrhenius equation. After 90 min of caramelization at 115 °C and 120 °C, the consistency coefficient significantly increased and samples demonstrated doughy structure, with no desirable sensory properties due to the formation of solid particles. The formation of furfural and linalool increased by increasing the time and temperature of caramelization which demonstrated that at 120 °C, the caramelization time should not exceed 90 min otherwise, bitterness flavors, burned and bad taste were sensed. The most desirable samples according to sensory evaluation were at temperatures below 120 °C. Ultimately, the most appropriate process conditions were determined for 110 °C (60–90 min) and 115 °C/60 min.

Rapid expansion supercritical solution (RESS) of CO2 as a green technology method for pineapple peels solid oil particle formation

Current development using the technique of Rapid Expansion Supercritical Solution (RESS) in solid oil particle formation pineapple peel contains a great deal active pharmacological which are anti-inflammatory, anti-oxidants, and anti-cancer agent. Many researchers use the conventional technique such as hydro-distillation, supercritical fluid extraction, and soxhlet extraction in order to extract the valuable component in oil formed. However, these techniques have several disadvantages such as long extraction time, high usage of solvent and produce toxic residual which can harm the environment. The RESS technique is not as time consuming as it will directly produce oil in particle formation, instead of conventional technique that need to undergo further technique such as spray drying in order to produce solid oil particle. In this study the extraction was conducted using temperature 40, 45, 50, 55, 60°C and the pressure used were 3000, 4000, 5000, 6000 and 7000 psi at a constant flowrate of 24ml/min for 50 minutes extraction time. The extracted component in solid oil particle was analyzed using Gas Chromatography Mass Spectrometry (GCMS) and show that pineapple peels is rich in volatile components such as 1-Hexene, 4-methyl, Benzene, 1,1’-(1,2 cyclobutanediyl) bis-, trans, and 1-Buten-3-one, 1-(2-carboxy-4,4-dimethylcyclobutenyl).

The Role of Solid Particles Obtained from Plant Materials in Improvement the Quality of Cosmetic Care Balms

Abstract The sensory properties of cosmetic emulsions are part of the basic properties of products such as face creams and body balms. They are extremely important parameters in the product evaluation by consumers. Cosmetics manufacturers are increasingly introducing ingredients in the form of solid particles (talc, bentonite, clay) into formulations to improve the sensory properties of products. Their addition simplifies the application of the emulsion on the skin, effects faster absorption and leaves a feeling of silky smoothness after application. During the work, we investigated solid particles of plant origin: powder from ground orange peel and oat grain. These ingredients were introduced into the formulation of the model body balms. The antioxidant and physicochemical properties of the obtained emulsions as well as the skin hydration after their application were evaluated. It has been shown that the introduction of solid plant particles increases the antioxidant properties of the emulsions and significantly improves emulsion stability and skin moisture after application.

Preparation and In Vitro Cytotoxicity Assessments of Spherical Silica-Encapsulated Liposome Particles for Highly Efficient Drug Carriers.

This work reports the formation of spherical solid silica-encapsulated liposome particles (SLPs) as functions of the concentration of silica precursor, reaction time, temperature, and volume ratios of solvent, respectively. The solid SLPs are more robust and have better drug-loading-efficiency liquid liposomes in carrier formulations. The liquid-state liposomes are hard to handle and have a lower drug-loading efficiency because they are fragile to external stimuli and have narrow hydrophobic phospholipid bilayers. The SLPs were obtained by silicification with tetraethyl orthosilicate (TEOS) in the hydrophilic region of phospholipid bilayers by a sol-gel process. These SLPs were characterized by scanning electron microscopy (SEM), focused ion beam (FIB)-SEM, confocal laser scanning microscopy (CLSM), thermogravimetric analysis (TGA), ζ-potential, X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, and UV-vis spectroscopy. The obtained SLPs were spherical with an average size of 2-3 μm. The hydrophilic region of the SLP phospholipid bilayers was confirmed using CLSM with green fluorescent fluorescein isothiocyanate (FITC) labeling and FIB-SEM. Furthermore, the drug-loading capacity and in vitro cytotoxicity assessments were performed using several drug compounds and L929 cells. The drug-loading capacity of the SLPs was >95%, and in particular, the hydrophobic drug-loading capacity was 2.3 times higher than that of general liposomes. Moreover, the result of an in vitro cytotoxicity assessment of the SLPs was good, about 99% of cell viability.

AIR QUALITY CONTROL MODEL (DUST PARTICLE) WITH SPRAY TOWER

Introduction:Air is a gas mixture that consists of several components and is spread throughout the area. Air pollution is the presence in the atmosphere in the form of solid particles, liquid droplets or gaseous components abnormally or in the presence in greater concentrations. There is an easy way to control air pollution by reducing the source of the pollution. However, control is part of air health as with the concept of water treatment. The purpose of this study was to design a device to defray the particles of spray tower dust at a low cost. Methods: This type of research used a pre experiment with the aim of testing the Spray Tower tool in reducing the levels of dust particles from the combustion process with coal briquettes, rice husks, and old tires. The pre test was coal briquettes, rice husk ash, and tires without being sprayed with water. The post test were coal, rice husks, and tires with sprayed water (with the help of 1 nozzle, 2 nozzles and 3 nozzles). The independent variable is the number of nozzles sprayed, the dependent variable includes a decrease in the level of dust particles while the disturbing variable consists of sprayed water discharge, weight of coal briquettes, rice husk ash and tires, air temperature, humidity, height of spraying tower, nozzle diameter. Result and discussion: of the study the average air temperature was 20.17oC, humidity was 82%. The water discharge for 1 nozzle is 47.76 ml / second, 2 nozzles are 83.75 ml / second and 3 nozzles are 113.76 ml / second. The initial particle content of old tires was 3,020,000 μg / m3, coal briquettes (420,000 μg / m3) and rice husk ash (110,000 μg / m3). The average content of used tire dust particles with one nozzle (1,273.33.33 μg / m3), coal briquettes with one nozzle (361,666.67 μg / m3) and rice husk with one nozzle (23,333.33 μg / m3). The average dust particle content of old tires with two nozzles (16,666.67 μg / m3), coal briquettes with two nozzles (195,000 μg / m3) and rice husks with two husks (18,333.33 μg / m3). The average content of used tire dust particles with three nozzles (13,333.33 μg / m3), coal briquettes with three nozzles (13,333.33 μg / m3) and rice husks with three husks (13,333.33 μg / m3). Conclusion:When compared with Government regulation no. 41 of 1999 is still far from the standard 230 μg / m3 (24 hours), 90 μg / m3 (1 hour). Suggestion It is necessary to conduct other similar studies with a larger sample size, varying air pollution groups, modified models and diameters, controlled gross flow rates.

Preparation of Cellulose Particles with a Hollow Structure.

In this study, we report the preparation of hollow cellulose particles via a solvent-releasing method with the ionic liquid 1-ethyl-3-methylimidazolium acetate ([Emim]Ac). A dispersion comprising [Emim]Ac droplets with dissolved cellulose and a hexane medium containing a stabilizer was poured into a large amount of acetone (precipitant), resulting in the precipitation of cellulose and the formation of solid cellulose particles with a hollow structure. We found that the formation of the hollow structure resulted from the equilibrium phase separation. Porous structures were also obtained using ethanol or t-butanol as a precipitant, where cellulose immediately precipitated (i.e., exhibited non-equilibrium phase separation). In the case where acetone was used as the precipitant, the diffusion rate of [Emim]Ac from the droplets into the precipitant was relatively low; that is, the precipitation of cellulose was delayed, which allowed the cellulose to be phase-separated into a thermodynamically stable structure (equilibrium phase separation), resulting in the formation of the hollow structure.

Modeling of the Thermal Decomposition of Methane and the Formation of Solid Carbon Particles

Mathematical models of methane decomposition during its pyrolysis, including nonstationary diffusion equations with and without taking into account the convective component of the decomposition process, have been developed and verified. Their exact analytical solutions have been obtained and further used in the study of a mathematical model of the formation of solid carbon particles arising during methane heating to the pyrolysis temperature. By studying the rate and intensity of the formation of solid carbon particles, it has been shown that particles of the smallest size are obtained at higher decomposition temperatures and for a shorter time.

Analysis of Soot Deposition Mechanisms on Nickel-Based Anodes of SOFCs in Single-Cell and Stack Environment

Solid oxide fuel cells (SOFCs) can be fueled with various gases, including carbon-containing compounds. High operating temperatures, exceeding 600 °C, and the presence of a porous, nickel-based SOFC anode, might lead to the formation of solid carbon particles from fuels such as carbon monoxide and other gases with hydrocarbon-based compounds. Carbon deposition on fuel electrode surfaces can cause irreversible damage to the cell, eventually destroying the electrode. Soot formation mechanisms are strictly related to electrochemical, kinetic, and thermodynamic conditions. In the current study, the effects of carbon deposition on the lifetime and performance of SOFCs were analyzed in-operando, both in single-cell and stack conditions. It was observed that anodic gas velocity has an impact on soot formation and deposition, thus it was also studied in depth. Single-anode-supported solid oxide fuel cells were fueled with gases delivered in such a way that the initial velocities in the anodic compartment ranged from 0.1 to 0.7 m/s. Both cell operation and post-mortem observations proved that the carbon deposition process accelerates at higher anodic gas velocity. Furthermore, single-cell results were verified in an SOFC stack operated in carbon-deposition regime by dry-coupling with a downdraft 150 kWth biomass gasifier.

On the Formation and Accumulation of Solid Carbon Particles in High-Enthalpy Flows Mimicking Re-Entry in the Titan Atmosphere

The problem relating to the formation of solid particles enabled by hypersonic re-entry in methane-containing atmospheres (such as that of Titan) has been tackled in the framework of a combined experimental–numerical approach implemented via a three-level analysis hierarchy. First experimental tests have been conducted using a wind tunnel driven by an industrial arc-heated facility operating with nitrogen as working gas (the SPES, i.e., the Small Planetary Entry Simulator). The formation of solid phases as a result of the complex chemical reactions established in such conditions has been detected and quantitatively measured with high accuracy. In a second stage of the study, insights into the related formation process have been obtained by using multispecies models relying on the NASA CEA code and the Direct Simulation Monte Carlo (DSMC) method. Through this approach the range of flow enthalpies in which carbonaceous deposits can be formed has been identified, obtaining good agreement with the experimental findings. Finally, the deposited substance has been analyzed by means of a set of complementary diagnostic techniques, i.e., SEM, spectroscopy (Raman, FTIR, UV–visible absorption and fluorescence), GC–MS and TGA. It has been found that carbon produced by the interaction of the simulated Titan atmosphere with a solid probe at very high temperatures can be separated into two chemically different fractions, which also include “tholins”.

Effect of charging solid particles on their growth process and parameters of microwave discharge in liquid n-heptane

A zero-dimensional non-stationary model of a microwave discharge in liquid n-heptane at atmospheric pressure with continuous argon injection into the plasma region is presented. The model includes equations for the kinetics of neutral and charged plasma components, equations describing the formation and growth of solid particles from the decomposition products of n-heptane, and an equation for the microwave field strength in plasma. The description of the coagulation process takes into account the electrostatic repulsion of solid particles due to their charge. The kinetics of charged particles is described taking into account their death on the surface of negatively charged solid particles formed in plasma. To determine the coefficients of the reaction rates in mechanisms of direct electron impact, the electron energy distribution function obtained by solving the Boltzmann equation is used. Calculations have shown that the plasma quasineutrality is mainly supported by the charge of solid particles, and the electron concentration is 1–2 orders of magnitude less than the total ion concentration. An increase in the averaged microwave field was noted in comparison with the case that does not take into account charging. Charging of the solid particles does not affect the composition of the main gas-phase products, but leads to the suppression of the coagulation process for large solid particles, which leads to a change in the size distribution function of the solid particles formed in the plasma.

Modeling and simulation of solid-containing droplet drying and different-structure particle formation

The formation of solid and hollow particles from solute precipitation of a liquid droplet was investigated using a simulative approach. The simulation model describes the evolution of the solute concentration, temperature gradient, and size change of the droplet and includes the vapor concentration and temperature gradient in the air surrounding the droplet. The volume of fluid (VOF) method was adopted to capture the gas–liquid–solid interface. The entire drying process was analyzed using a sodium chloride aqueous droplet as an example. The influence of ambient temperature on the final structure of the precipitate particle was studied. Two distinct particle structures were discussed. The droplet solidifies into a solid particle when the ambient temperature is low, and into a hollow shape when the ambient temperature is high. The mechanisms underlying these two particle structures were discussed.

Analysis of the main parameters of crude oil pipeline transport

The paper presents results of experimental research and simulation of the main parameters of crude oil pipeline transport. In Serbia, 70 % of the produced oil belongs to a paraffin type, of which over 25 % has a high content of paraffin. High-content paraffin oil usually has a high pour point. The paraffin content in crude oil from Vojvodina, Serbia, is in the range 7.5 to 26 %, and the oil pour temperature varies from 18 to 36?C. The imported crude oil has a flow point max. 8?C. Homogenization, i.e. mixing of domestic and imported crude oil, improves the transport properties and decreases the pour point. After homogenization, the crude oil is pre-heated, and then transported by a pipeline to the refinery for further processing. Heating induces modification of crude oil physical properties, especially flow properties so to prevent wax formation within the oil pipeline. The aim of this paper was to determine operating parameters and flow characteristics for a particular oil pipeline (428 mm inner diameter, 91,000 m length) under real operating conditions. By heating in the range of 20 - 50?C, the viscosity of crude oil was reduced, approaching the viscosity of water. The pipeline is isolated (100 mm thick isolation) and buried into in the ground (1 m depth). It is found that the heat transfer coefficient has a dominant influence on the cooling rate of the oil in the pipeline. The heat transfer coefficient is mainly determined by the isolation thickness so that it was determined as 0.60 W m-2 K-1 for + 100 mm thickness, while it was 2.20 W m-2 K-1 for the non-isolated pipeline. Heat losses through the main pipeline ranged from 36 - 110 kJ m-1 h-1 (10 - 30 W m-1). The difference between the starting and the ending temperature of crude oil ranged from 10 to 12?C. Such a decrease of ?t = 10 oC and, consequently, the increase in viscosity induced a noti-ceable increase in the pressure drop and pump power by 3 to 4 %, at the maximum flowrate of 0.194 m3 s-1 (700 m3 h-1). The cooling rate during transportation under stationary thermal and hydraulic conditions is in the range 0.52 ? 0.5 oC h-1. In the case of domestic oil (Vojvodina, Serbia) transport, the downtime should not exceed 24 h, since stopping and cooling of the oil would result in formation of solid paraffin particles followed by oil gelation.

Influence of ethanol on the combustion process and soot formation in the diesel cylinder

Ethanol is an attractive alternative fuel because it is a renewable bio-based resource and it is oxygenated, thereby providing the potential to reduce particulate emissions in compression–ignition engines. Thus, the use of ethanol in a diesel engine can simultaneously solve two important problems - the replacement of non-renewable diesel fuel and improving the environmental performance of diesel by reducing soot emissions into the atmosphere. Thus, the use of ethanol in a diesel engine can simultaneously solve two important problems - the replacement of non-renewable diesel fuel and improving the environmental performance of diesel by reducing soot emissions into the atmosphere. The presented work considers the main reasons for reducing the formation of solid particles in the diesel cylinder, taking into account the transformation of the combustion process. The article presents the results of experimental studies to reduce the soot content in the exhaust gases by direct injection of ethanol into the combustion chamber with ignition from the burning fuel jet. The implementation of this method somewhat complicates the design of the diesel engine but allows you to control the combustion process and exclude the maximum amount of diesel fuel. The characteristics of the combustion process of alternative fuels in the diesel cylinder and the main patterns of change are described. In conclusion, the main problems of the use of ethanol and promising directions of its use as a fuel for the engine with compression ignition are considered, taking into account the peculiarities of the combustion process and the formation of harmful components of exhaust gases.

Rapid Expansion Supercritical Solution (RESS) of Carbon Dioxide as a Green Technology Method for Leucaena Leucocephala Solid Oil Particle Formation

Rapid expansion supercritical solution (RESS) is a technology introduced that produces a small solid oil particle with organic solvent free particle. RESS method is a better method compared to the traditional method due to many advantages such are produce clean extraction yields, obtain free solvent traces, environmental friendly and short processing time can be used in various industries such as cosmetic and pharmaceutical. Therefore, RESS technique is applied in order to produce direct solid oil particle from Luecaena leucocephala (L.leucocephala) pods instead of oil. In this study, the operating condition that applied during the RESS process in order to obtain the highest solid oil particle from the L.leucocephala pods sample are extraction temperature of 40 ºC, 45 ºC, 50 ºC, 55 ºC and 60 ºC and extraction pressure of 3000 psi, 4000 psi, 5000 psi, 6000 psi and 7000 psi at the constant extraction time of 40 minutes. The highest yield of L.leucocephala solid oil particles that obtained is about 0.65% at 60 oC and 7000 psi. The major components that obtained from the highest yield are 2,2,3-trimethyldecane, Cyclopentanone, propanoic acid and Cyclobutane, 1,2-diphenyl- by as identified by using Gas Chromatography Mass Spectrometry (GCMS).

On the influence of nucleation and growth of S8 and Li2S in lithium-sulfur batteries

Lithium-sulfur (Li–S) batteries have the potential to outperform state-of-the-art lithium-ion batteries. One of the bottle necks is the limited power density which most conversion based systems have in common. One of the reasons is the formation of solid, insulating charge and discharge products which passivate active surfaces during operation of the cell. In depth knowledge of the formation and dissolution is needed in order to develop counter-measures overcoming the current limitations. In this article we present a continuum model of Li–S batteries including a detailed description of the formation and dissolution of solid particles based on the classical theory of nucleation and growth. By evolving a particle size distribution of the Li2S and S8 phase we are able to provide a qualitative description of the resulting particle morphology as well as their effect on active surface areas and transport processes. Results of the simulations are in agreement with experimental data published in the literature. We perform intensive parameter studies which provide guidelines for the development of surface modifications enabling a spatial control of solid discharge product precipitation resulting in improved battery performance.

Complex dynamical interplay between solid particles and flow in driven granular suspensions

Granular materials immersed in a fluid are ubiquitous in daily life, industry, and nature. They include food processing, pastes, cosmetics, paints, concretes, cements, muds, wet sands, snows, landslides, and lava flow. They are known to exhibit a rich variety of complex rheological behavior, but the role of a fluid component in such behavior has remained poorly understood due to the nonlocal and many-body nature of hydrodynamic interactions between solid particles mediated by the fluid. We address this fundamental problem by comparing the microrheological response of athermal granular suspensions with and without hydrodynamic interactions to an externally driven probe particle by numerical simulations. We find that the presence of the fluid drastically increases the drag coefficient of the probe particle by more than one order of magnitude near the jamming transition. We reveal that this is a consequence of the nontrivial long-range nature of hydrodynamic interactions, which originates from unlimited cumulative transmission of near-field hydrodynamic interactions due to the incompressibility of both fluid and solid particles. Force chain formation of solid particles is dynamically coupled with hydrodynamic flow, leading to strong spatiotemporal fluctuations of flow pattern and nonlinear rheological response. Our study reveals essential roles of hydrodynamic interactions in complex rheological behavior of dense granular suspensions under an external drive.

Time Transient Electrochemical Monitoring of Tetraalkylammonium Polybromide Solid Particle Formation: Observation of Ionic Liquid-to-Solid Transitions.

Energy storage systems (ESSs) using a Br-/Br2 redox reaction such as a Zn/Br redox flow battery (RFB) or a redox-enhanced electrochemical capacitor (Redox-EC) suffer from self-discharge reactions resulting in significant Coulombic loss. To inhibit the self-discharge, quaternary ammonium (Q+) and tetraalkylammonium (T+) bromide are added to form ionic liquid (QBr2 n+1) and solid (TBr3) polybromides during the ESS charging process. The electrochemical formation of liquid QBr2 n+1 and its electrochemical properties have been examined. The detailed mechanisms of ionic solid TBr3 formation, however, have not yet been explored. In this article, we analyzed the ionic liquid-to-solid phase transition of TBr3 particles using a time transient electrochemical method. We suggest the formation of ionic solid TBr3 particles via hydrated TBr3 droplets as an intermediate phase, which are generated by electro-oxidation of Br- in an aqueous TBr solution. We found the phase transition time of TBr3 particles is strongly dependent on the chemical structure of T+ and the concentration of TBr in an aqueous solution.

1D Modeling of the Microwave Discharge in Liquid n-Heptane Including Production of Carbonaceous Particles

Microwave plasma in the liquid is initiated inside a gas bubble formed at the end of the electrode-antenna, through which microwave energy is introduced into the liquid. A 1D model a set of gas phase kinetic reactions describes the evolution processes of ionization, heat transfer and formation of gas and solid products inside the plasma bubble. The code is based on joint solution of the Boltzmann equation for free electrons of the plasma, a simplified equation for the microwave field, the heat conduction equation, the balance equation for the electron density and the balance equations for the weight fraction for all gas and solid products of n-heptane pyrolysis. The Joule heat released in the plasma is expended on the evaporation of liquid n-heptane into the bubble and the decomposition of the n-heptane molecules. The model includes both the description of gas phase processes and formation of solid carbon-containing particles. The growth mechanism for generation of solid particles describes simultaneous processes of the initial nucleation, surface growth and coagulation of soot particles. The results of calculations are compared with known experimental results.

Formation and evolution of solid particles in the early solar system: A participant’s view of Frontier Seminar 2019

Formation and evolution of solid particles in the early solar system: A participant’s view of Frontier Seminar 2019

Bonded, Grounded, and Burned to a Crisp: Electrostatic Ignition of Flammable Gases

Ignition by electrostatic discharge of clean flammable gas, such as natural gas, being released to the atmosphere during blowdown operations is unlikely. However, the presence of foreign material in the form of solid particles or liquid droplets changes the risk level significantly. The discharge of a flammable gas stream with a cloud of foreign material poses a potential electrostatic hazard, even if the piping system and associated equipment is otherwise bonded and grounded. The foreign material may be capable of accumulating sufficient electrostatic potential to ignite the flammable gas. There have been several documented incidents where ignition has occurred during a flammable gas blowdown. In some instances, gas lines were being cleaned, while in others, the blowdown was completed as a safety measure for another process. This article will focus on a case study where a stream of flammable gas was ignited during a blowdown and an obvious ignition source (other than electrostatic discharge) was not present, but foreign material was observed. © 2018 American Institute of Chemical Engineers Process Saf Prog 38: e12024, 2019