scholarly journals Stationary characteristics in bipolar diffusion charging of aerosols: Improving the performance of electrical mobility size spectrometers

2018 ◽  
Vol 52 (8) ◽  
pp. 809-813 ◽  
Author(s):  
Xiaotong Chen ◽  
Peter H. McMurry ◽  
Jingkun Jiang
2021 ◽  
Vol 7 (2) ◽  
pp. 44
Author(s):  
Francesca Picca ◽  
Angela Di Pietro ◽  
Mario Commodo ◽  
Patrizia Minutolo ◽  
Andrea D’Anna

In this study, flame-formed carbon nanoparticles of different nanostructures have been produced by changing the flame temperature. Raman spectroscopy has been used for the characterization of the carbon nanoparticles, while the particle size has been obtained by online measurements made by electrical mobility analysis. The results show that, in agreement with recent literature data, a large variety of carbon nanoparticles, with a different degree of graphitization, can be produced by changing the flame temperature. This methodology allows for the synthesis of very small carbon nanoparticles with a size of about 3-4 nm and with different graphitic orders. Under the perspective of the material synthesis process, the variable-temperature flame-synthesis of carbon nanoparticles appears as an attractive procedure for a cost-effective and easily scalable production of highly tunable carbon nanoparticles.


2020 ◽  
Vol 102 (24) ◽  
Author(s):  
Maurizio Monti ◽  
K. D. G. Imalka Jayawardena ◽  
Edward Butler-Caddle ◽  
Rajapakshe M. I. Bandara ◽  
Jack M. Woolley ◽  
...  

2019 ◽  
Vol 127 ◽  
pp. 102-115 ◽  
Author(s):  
Runlong Cai ◽  
Jingkun Jiang ◽  
Sander Mirme ◽  
Juha Kangasluoma
Keyword(s):  

1987 ◽  
Vol 18 (4) ◽  
pp. 409-417 ◽  
Author(s):  
Deyuan Wu ◽  
Andrew R. McFarland ◽  
Robert A. Fjeld

Author(s):  
Steven L. Alderman ◽  
Chen Song ◽  
Serban C. Moldoveanu ◽  
Stephen K. Cole

AbstractThe relatively volatile nature of the particulate matter fraction of e-cigarette aerosols presents an experimental challenge with regard to particle size distribution measure-ments. This is particularly true for instruments requiring a high degree of aerosol dilution. This was illustrated in a previous study, where average particle diameters in the 10-50 nm range were determined by a high-dilution, electrical mobility method. Total particulate matter (TPM) masses calculated based on those diameters were orders of magnitude smaller than gravimetrically determined TPM. This discrepancy was believed to result from almost complete particle evaporation at the dilution levels of the electrical mobility analysis. The same study described a spectral transmission measurement of e-cigarette particle size in an undiluted state, and reported particles from 210-380 nm count median diameter. Observed particle number concentrations were in the 10Described here is a study in which e-cigarette aerosols were collected on Cambridge filters with adsorbent traps placed downstream in an effort to capture any material passing through the filter. Amounts of glycerin, propylene glycol, nicotine, and water were quantified on the filter and downstream trap. Glycerin, propylene glycol, and nicotine were effciently captured (> 98%) by the upstream Cambridge filter, and a correlation was observed between filtration efficiency and the partial vapor pressure of each component. The present analysis was largely inconclusive with regard to filter efficiency and particle-vapor partitioning of water. [Beitr. Tabakforsch. Int. 26 (2014) 183-190]


1994 ◽  
Vol 339 ◽  
Author(s):  
T. J. Kistenmacher ◽  
S. A. Ecelberger ◽  
W. A. Bryden

ABSTRACTIntroduction of a buffer layer to facilitate heteroepitaxy in thin films of the Group IIIA nitrides has had a tremendous impact on growth morphology and electrical transport. While AIN- and self-seeded growth of GaN has captured the majority of attention, the use of AIN-buffered substrates for InN thin films has also had considerable success. Herein, the properties of InN thin films grown by reactive magnetron sputtering on AIN-buffered (00.1) sapphire and (111) silicon are presented and, in particular, the evolution of the structural and electrical transport properties as a function of buffer layer sputter time (corresponding to thicknesses from ∼50Å to ∼0.64 μm) described. Pertinent results include: (a) for the InN overlayer, structural coherence and homogeneous strain normal to the (00.1) growth plane are highly dependent on the thickness of the AIN-buffer layer; (b) the homogeneous strain in the AIN-buffer layer is virtually nonexistent from a thickness of 200Å (where a significant X-ray intensity for (00.2)AIN is observed); and (c) the n-type electrical mobility for films on AIN-nucleated (00.1) sapphire is independent of AIN-buffer layer thickness, owing to divergent variations in carrier concentration and film resistivity. These effects are in the main interpreted as arising from a competition between the lattice mismatch of the InN overlayer with the substrate and with the AIN-buffer layer.


2021 ◽  
Vol 12 (3) ◽  
pp. 194-201
Author(s):  
V. L. Solomakho ◽  
A. A. Bagdun

The quality of nanomaterials and nanotechnologies is largely determined by the stability of the applied technologies, which, to a large extent, depend on the constancy of particle sizes. In this regard, metrological problems arise that are associated both with measuring the dimensions of the microstructure of aerosols, suspensions and powders, and with ensuring the uniformity of measurements when transferring a unit of a physical quantity from a standard to working measuring instruments. The purpose of this work was to determine and calculate the error in transferring the size of a unit of length when measuring the diameter of nanoparticles.An analyzer of differential electric mobility of particles was determined as a reference measuring instrument for which the calculation was made. It allows the separation of aerosol particles based on the dependence of their electrical mobility on the particle size. In combination with a condensation particle counter, it allows you to scan an aerosol and build a particle size distribution function. This measurement method is the most accurate in the field of measuring the diameters of particles in aerosols, therefore, the error in the transmission of particle size must be set as for a standard.The paper describes the physical principles of measurement by this method and presents an equation for determining the diameter of nanoparticles. Based on this equation, the sources of non-excluded systematic error were identified. Also, an experimental method was used to determine the random component of the measurement error of nanoparticles and to calculate the error in transferring the size of a unit of length when measuring the diameter of nanoparticles.The obtained results will be used for metrological support of standard samples of particle size, ensuring traceability of measurements of aerosol particle counters and for aerosol research.


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