scholarly journals Formulation of Bicelles Based on Lecithin-Nonionic Surfactant Mixtures

Materials ◽  
2020 ◽  
Vol 13 (14) ◽  
pp. 3066
Author(s):  
Kenji Aramaki ◽  
Keita Adachi ◽  
Miho Maeda ◽  
Jitendra Mata ◽  
Junko Kamimoto-Kuroki ◽  
...  
Keyword(s):  
Particle Size ◽  
Nonionic Surfactant ◽  
Size Distribution ◽  
Soybean Lecithin ◽  
Low Cost ◽  
Surfactant Mixtures ◽  
Temperature Dependent ◽  
Size Change ◽  
Structure Transition ◽  
Biological Studies

Bicelles have been intensively studied for use as drug delivery carriers and in biological studies, but their preparation with low-cost materials and via a simple process would allow their use for other purposes as well. Herein, bicelles were prepared through a semi-spontaneous method using a mixture of hydrogenated soybean lecithin (SL) and a nonionic surfactant, polyoxyethylene cholesteryl ether (ChEO10), and then we investigated the effect of composition and temperature on the structure of bicelles, which is important to design tailored systems. As the fraction of ChEO10 (XC) was increased, a bimodal particle size distribution with a small particle size of several tens of nanometers and a large particle size of several hundred nanometers was obtained, and only small particles were observed when XC ≥ 0.6, suggesting the formation of significant structure transition (liposomes to bicelles). The small-angle neutron scattering (SANS) spectrum for these particles fitted a core-shell bicelle model, providing further evidence of bicelle formation. A transition from a monomodal to a bimodal size distribution occurred as the temperature was increased, with this transition taking place at lower temperatures when higher SL-ChEO10 concentrations were used. SANS showed that this temperature-dependent size change was reversible, suggesting the SL-ChEO10 bicelles were stable against temperature, hence making them suitable for several applications.

Characterization of the emission behavior of pulse-jet cleaned filters using a low-cost particulate matter sensor/Charakterisierung der Emission von druckstoßgereinigten Oberflächenfiltern mit einem Low-Cost-Feinstaubsensor

Gefahrstoffe ◽  
2019 ◽  
Vol 79 (11-12) ◽  
pp. 443-450
Author(s):  
P. Bächler ◽  
J. Meyer ◽  
A. Dittler
Keyword(s):  
Particle Size ◽  
Particulate Matter ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Low Cost ◽  
Particle Emission ◽  
Filter Medium ◽  
Emission Measurement ◽  
Pm2.5 Concentration ◽  
Pulse Jet

The reduction of fine dust emissions with pulse-jet cleaned filters plays an important role in industrial gas cleaning to meet emission standards and protect the environment. The dust emission of technical facilities is typically measured “end of pipe”, so that no information about the local emission contribution of individual filter elements exists. Cheap and compact low-cost sensors for the detection of particulate matter (PM) concentrations, which have been prominently applied for immission monitoring in recent years have the potential for emission measurement of filters to improve process monitoring. This publication discusses the suitability of a low-cost PM-sensor, the model SPS30 from the manufacturer Sensirion, in terms of the potential for particle emission measurement of surface filters in a filter test rig based on DIN ISO 11057. A Promo® 2000 in combination with a Welas® 2100 sensor serves as the optical reference device for the evaluation of the detected PM2.5 concentration and particle size distribution of the emission measured by the low-cost sensor. The Sensirion sensor shows qualitatively similar results of the detected PM2.5 emission as the low-cost sensor SDS011 from the manufacturer Nova Fitness, which was investigated by Schwarz et al. in a former study. The typical emission peak after jet-pulse cleaning of the filter, due to the penetration of particles through the filter medium, is detected during Δp-controlled operation. The particle size distribution calculated from the size resolved number concentrations of the low-cost sensor yields a distinct distribution for three different employed filter media and qualitatively fits the size distribution detected by the Palas® reference. The emission of these three different types of filter media can be distinguished clearly by the measured PM2.5 concentration and the emitted mass per cycle and filter area, demonstrating the potential for PM emission monitoring by the low-cost PM-sensor. During the period of Δt-controlled filter aging, a decreasing emission, caused by an increasing amount of stored particles in the filter medium, is detected. Due to the reduced particle emission after filter aging, the specified maximum concentration of the low-cost sensor is not exceeded so that coincidence is unlikely to affect the measurement results of the sensor for all but the very first stage of filter life.

A Simplified Model for the Flow Inside Cascade Impactor

2013 ◽  
Author(s):  
Seyyed Mahdi Nemati Mehr ◽  
Salman Sohrabi ◽  
Pedram Falsafi ◽  
Paniz Gorji
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Low Cost ◽  
Mass Difference ◽  
Cascade Impactor ◽  
Computational Method ◽  
Simplified Model ◽  
Unit Value ◽  
Cascade Impactors

In this paper we developed a new mathematical model for the flow inside cascade impactors and via this simplified model, we determined the particle size distribution by a fast and low cost computational method. Using cascade impactors for determining the particle size distribution, one can use comprehensive CFD methods to fully simulate the particle traces. Although the results from those CFD analyses can be very accurate, usually that is not a time and cost efficient routine. In contrast, we showed that by using our proposed calculation we can estimate the particle size distribution very fast and yet with the slight error — comparing to the results from CFD method. Cascade impactors are being used to measure the range of substances moving through an opening and determine the particle size of distributed substances. Air flow containing aerosol entering in each stage, after colliding vertically with a plate will deviate 90 degrees from its original direction. Larger (massive) particles cannot follow the flow because of their larger linear momentum. Hence, they will deviate from the flow and deposit on the plate instead. The mass difference before and after the experiment represents the deposited mass in each stage. By integrating multiple uniquely designed stages into one impactor, we can determine size of particles in the flow. Typical cascade impactors consist of up to ten stages in which different size of aerosols are being separated. This paper presents a simple model for the flow in one single stage of a cascade impactor. Flow inside cascade impactor is approximated by stagnation point potential flow with the stream function of Psi = Axy, and particles are tracked by velocity verlet algorithm. Absorbed particles are associated with unit value; otherwise they are associated with zero. It is assumed that particles in entrance have random size distribution and location. Drag, Saffman and Brownian forces are taken into account in this model for different particle sizes. The results are discussed in detail and compared with data driven from different approaches in the literature.

scholarly journals Developing a Relative Humidity Correction for Low-Cost Sensors Measuring Ambient Particulate Matter

Sensors ◽  
2018 ◽  
Vol 18 (9) ◽  
pp. 2790 ◽  
Author(s):  
Andrea Di Antonio ◽  
Olalekan Popoola ◽  
Bin Ouyang ◽  
John Saffell ◽  
Roderic Jones
Keyword(s):  
Particle Size ◽  
Particulate Matter ◽  
Relative Humidity ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Low Cost ◽  
Monitoring Networks ◽  
Ambient Particulate Matter ◽  
Correction Algorithm ◽  
Ambient Conditions

There is increasing concern about the health impacts of ambient Particulate Matter (PM) exposure. Traditional monitoring networks, because of their sparseness, cannot provide sufficient spatial-temporal measurements characteristic of ambient PM. Recent studies have shown portable low-cost devices (e.g., optical particle counters, OPCs) can help address this issue; however, their application under ambient conditions can be affected by high relative humidity (RH) conditions. Here, we show how, by exploiting the measured particle size distribution information rather than PM as has been suggested elsewhere, a correction can be derived which not only significantly improves sensor performance but which also retains fundamental information on particle composition. A particle size distribution–based correction algorithm, founded on κ -Köhler theory, was developed to account for the influence of RH on sensor measurements. The application of the correction algorithm, which assumed physically reasonable κ values, resulted in a significant improvement, with the overestimation of PM measurements reduced from a factor of ~5 before correction to 1.05 after correction. We conclude that a correction based on particle size distribution, rather than PM mass, is required to properly account for RH effects and enable low cost optical PM sensors to provide reliable ambient PM measurements.

The Effects of Surfactants on the Granularity of the HA Powder Synthesized by Mechanochemistry

2009 ◽  
Vol 610-613 ◽  
pp. 1323-1326
Author(s):  
Tao Yu ◽  
Jian Dong Ye ◽  
Ying Jun Wang
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Fine Particles ◽  
Low Cost ◽  
Sodium Hexametaphosphate ◽  
X Ray Diffraction ◽  
Laser Scattering ◽  
X Ray ◽  
Batch Sizes

The hydroxyapatite (HA) was synthesized by wet mechanochemical method；the effects of surfactant, such as triethanolamine, polyethylene glycol (200000), sodium hexametaphosphate, polyvinylpyrrolidone (K30), on the particle size distribution of as-prepared HA powder were studied. Results were characterized by means of X-ray diffraction (XRD), Scanning electron microscopy (SEM), Laser Scattering Particle Size Distribution Analyzer. The results show that the addition of surfactants eliminated the agglomeration of the powder and the uniform, fine particles (D10=0.1149μm, D50=0.12551μm, D90=0.1481μm) were obtained with the Triethanolamine (6 wt %) and Sodium hexametaphosphate (4 wt %) respectively. Our work demonstrates applicability of the mechanosynthesis for reproducible and low-cost synthesis of uniform, fine HCA powder in large batch-sizes.

scholarly journals A Simple and Low Cost Technique for Determining the Granulometry of Upflow Anaerobic Sludge Blanket Reactor Sludge

1999 ◽  
Vol 40 (8) ◽  
pp. 1-8 ◽  
Author(s):  
A. Laguna ◽  
A. Ouattara ◽  
R. O. Gonzalez ◽  
O. Baron ◽  
G. Famá ◽  
...  
Keyword(s):  
Particle Size ◽  
Size Distribution ◽  
Tap Water ◽  
Low Cost ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Solid Loss ◽  
Size Profile ◽  
Anaerobic Sludge Blanket

Four techniques (microscope sizing, calculation from settling velocities, image and laser analysis) are available nowadays for determining the particle size distribution of upflow anaerobic sludge blanket (UASB) reactor sludge. These techniques present however the disadvantage of being either tedious, imprecise or expensive and hardly applicable in full scale treatment plants. There was then the need for a simple and low cost technique. In this study, a granulometry procedure based on manual humid sieving was evaluated. It was shown that no solid loss occured during the screening and that the particle size profiles were reproducible when performed with sludge samples of 5, 10, 25 and 150 ml, but not 1 ml. Only the results between 10 and 25 ml were however fully identical. It was shown also that the sieving could be performed on sludge samples stored for as long as 50 days at refrigerator temperature and that tap water could be use for the wash and backwash operations without any impact on the particle size profile. The granulometry obtained by image analysis was not comparable to that given by sieving. Nevertheless, no evidence of granule erosion could be found. In any case, the technique allowed us to follow the evolution of sludge granulometry perfectly over time. As a consequence, the manual humid sieving appears to be an adequate technique for determining the granule size distribution of UASB sludges.

Particle size spectrometer using inertial classification and electrical measurement techniques for real-time monitoring of particle size distribution

Lab on a Chip ◽  
2018 ◽  
Vol 18 (17) ◽  
pp. 2642-2652 ◽  
Author(s):  
Hong-Beom Kwon ◽  
Hong-Lae Kim ◽  
Ui-Seon Hong ◽  
Seong-Jae Yoo ◽  
Kyongtae Kim ◽  
...  
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Real Time ◽  
Low Cost ◽  
Measurement Techniques ◽  
Electrical Measurement ◽  
Real Time Monitoring

We present a low-cost and compact particle size spectrometer that can accurately monitor particle size distribution.

scholarly journals Direct Visualisation, Sizing and Counting of Virus and Phage Particles in Liquids

2009 ◽  
Vol 17 (1) ◽  
pp. 34-37
Author(s):  
Bob Carr ◽  
Duncan Griffiths
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Low Cost ◽  
Correlation Spectroscopy ◽  
Particle Analysis ◽  
Distribution Data ◽  
Attractive Alternative ◽  
Nano Particle ◽  
Analysis System

A laser-based, single nano-particle tracking analysis system was described in the March issue of Microscopy Today. The LM series of analyzers from NanoSight allows nanoscale particles such as viruses to be directly and individually visualised in liquids in real time, from which high-resolution particle size distribution profiles can be obtained, figure 1. The technique is fast, robust, accurate, and low cost representing an attractive alternative or complement to expensive and more complex methods of nano-particle analysis such as dynamic light scattering (photon correlation spectroscopy) or electron microscopy.By simultaneously and directly measuring the diffusion coefficient of each and every particle, the dedicated Nanoparticle Tracking Analysis (NTA) software suite allows the user to automatically count and size the viruses in a sample. Results are displayed as graphs of size against count of individual particles (or size versus relative brightness), thus overcoming the limitations inherent in other particle analysis systems that generate only mean particle size distribution data with resolution.

scholarly journals A Low Cost Synthesis and Characterization of CuO Nanoparticles for Photovoltaic Applications

2019 ◽  
Vol 60 (1) ◽  
pp. 17-23
Author(s):  
A. A. Yankson ◽  
A. Kuditcher ◽  
G. Gebreyesus ◽  
M. N. Y. H. Egblewogbe ◽  
J. K. A. Amuzu ◽  
...  
Keyword(s):  
Particle Size ◽  
Size Distribution ◽  
Cupric Oxide ◽  
Low Cost ◽  
Cuo Nanoparticles ◽  
Oxide Nanoparticles ◽  
X Ray Diffraction ◽  
X Ray ◽  
Photovoltaic Applications ◽  
Cupric Oxide Nanoparticles

A simple low cost chemical route has been used to synthesize cupric oxide nanoparticles. The synthesized CuO nanoparticles were characterized using XRD, TEM and UV-absorption. X-ray diffraction analysis showed the synthesized nanoparticles to be a pure cupric oxide. EDAX analysis showed the presence of copper and Oxygen in the as prepared CuO nano particles, with the AAS indicating that Cu2+ represented 53.5% of the sample. The particle size and particle size distribution of the cupric oxide nanoparticles were obtained by transmission electron microscopy (TEM) whereas the crystallite size and crystallite size distribution were obtained by X-ray diffraction. The particle size was found to be between 20 nm and 60 nm. The particle size distribution obtained from cumulative percentage frequency plots features a log-normal function. Absorbance measurements and analysis showed that the material has an absorbance peak at 314 nm and energy bandgap of 1.48 eV, making it a good candidate for photovoltaic applications.

Temperature Effect on the Stability of CuO Nanofluids Based on Measured Particle Distribution

2005 ◽  
Vol 295-296 ◽  
pp. 51-56 ◽  
Author(s):  
Ho Chang ◽  
Chih Hung Lo ◽  
Tsing Tshih Tsung ◽  
Y.Y. Cho ◽  
D.C. Tien ◽  
...  
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Copper Oxide ◽  
Temperature Effect ◽  
Size Distribution ◽  
Nanoparticle Synthesis ◽  
Experimental Result ◽  
Size Change ◽  
Normal Fluid ◽  
Environment Temperature

This study aims to investigate the temperature effect on particle size of copper oxide nanofluid produced under optimal parameters of the Arc Spray Nanoparticle Synthesis System (ASNSS) developed in this research. The purpose is to understand the aggregation feature of copper oxide nanofluid in a higher-than-room-temperature environment and to analyze its size change and the motion behavior of suspended nanoparticles. This study employs an ambient temperature controller to maintain the environment temperature within the scope of normal fluid work temperature to obtain data on the change in suspended particles of copper oxide nanofluid under varying temperatures and through change of time. Experimental result shows that the particle size distribution of copper oxide nanofluid changes when the temperature rises due to the slight absorption and aggregation phenomena between particles, and that the change in environmental temperature can accelerate the aggregation of copper oxide nanofluid, which can affect its stability in application. However, the change in particle size distribution will gradually stabilize for a longer duration of constant temperature.

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