Penetration of charged particles through metallic tubes

Chang, Kuang-Nan; Chen, Yu-Kang; Huang, Sheng-Hsiu; Chen, Chun-Wan; Lai, Chane-Yu; Chen, Chih-Chieh

doi:10.1016/j.jaerosci.2012.01.006

Cited by 16 publications

(12 citation statements)

References 12 publications

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“…6), differs markedly from the linear loss rate retrieved for the sulfuric acid neutral monomer (1.7 × 10 −3 s −1 , Almeida et al, 2013). This difference between the loss rates might be partially explained by the image charge effect of the ions with the chamber walls, even though this remains a controversial topic (McMurry and Rader, 1985;Mayya and Sapra, 2002;Vauge, 2002;Chang et al, 2012). Losses might be due to some non-ideal behavior, e.g., retention of surface charge, of some insulator in the clearing field cage region or in proximity to the mixing fans.…”

Section: Resultsmentioning

confidence: 84%

Experimental investigation of ion–ion recombination under atmospheric conditions

et al. 2015

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Abstract. We present the results of laboratory measurements of the ion-ion recombination coefficient at different temperatures, relative humidities and concentrations of ozone and sulfur dioxide. The experiments were carried out using the Cosmics Leaving OUtdoor Droplets (CLOUD) chamber at CERN, the walls of which are made of conductive material, making it possible to measure small ions. We produced ions in the chamber using a 3.5 GeV c −1 beam of positively charged pions (π + ) generated by the CERN Proton Synchrotron (PS). When the PS was switched off, galactic cosmic rays were the only ionization source in the chamber. The range of the ion production rate varied from 2 to 100 cm −3 s −1 , covering the typical range of ionization throughout the troposphere. The temperature ranged from −55 to 20 • C, the relative humidity (RH) from 0 to 70 %, the SO 2 concentration from 0 to 40 ppb, and the ozone concentration from 200 to 700 ppb. The best agreement of the retrieved ion-ion recombination coefficient with the commonly used literature value of 1.6 × 10 −6 cm 3 s −1 was found at a temperature of 5 • C and a RH of 40 % (1.5 ± 0.6) Published by Copernicus Publications on behalf of the European Geosciences Union. A. Franchin et al.: Experimental investigation× 10 −6 cm 3 s −1 . At 20 • C and 40% RH, the retrieved ion-ion recombination coefficient was instead (2.3 ± 0.7) × 10 −6 cm 3 s −1 . We observed no dependency of the ion-ion recombination coefficient on ozone concentration and a weak variation with sulfur dioxide concentration. However, we observed a more than fourfold increase in the ion-ion recombination coefficient with decreasing temperature. We compared our results with three different models and found an overall agreement for temperatures above 0 • C, but a disagreement at lower temperatures. We observed a strong increase in the recombination coefficient for decreasing relative humidities, which has not been reported previously.

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Section: Resultsmentioning

confidence: 84%

Experimental investigation of ion–ion recombination under atmospheric conditions

et al. 2015

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“…DPI performance could be improved by taking advantage of electrostatic charges present on the particles. Several theoretical and experimental studies concluded that particles with higher levels of electrostatic charge have a higher probability to deposit on the airway surfaces due to higher attractive forces (Chang et al, 2012;Cohen et al, 1998Cohen et al, , 1995Fleming et al, 1996).…”

Section: Influence Of Electrostatic Charge On Aerosol Lung Depositionmentioning

confidence: 99%

“…Particle deposition by image charge is only important in the alveolar airways for low-density particles (Koolpiruck et al, 2004). The use of electrostatic principles to improve the efficiency of pulmonary drug delivery has been discussed elsewhere (Chang et al, 2012;Koolpiruck et al, 2004;Wong et al, 2013).…”

Section: Influence Of Electrostatic Charge On Aerosol Lung Depositionmentioning

confidence: 99%

A review of factors affecting electrostatic charging of pharmaceuticals and adhesive mixtures for inhalation

Kaialy

2016

International Journal of Pharmaceutics

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Pharmaceutical powders are typically insulators consisting of relatively small particles and thus they usually exhibit significant electrostatic charging behaviours. In the inhalation field, the measurement of electrostatic charge is an imperative stage during pharmaceutical formulation development. The electrostatic charge is affected by the interplay of many factors. This article reviews the factors affecting the electrostatic charging of pharmaceutical powders with a focus on dry powder inhalations. The influences of particle resistivity, size distribution, shape distribution, surface roughness, polymorphic form and hygroscopicity, as well as the effects of moisture uptake, environmental conditions, pharmaceutical processing (i.e., milling, sieving, spray drying and blending), and storage on the electrostatic charge behaviours of pharmaceuticals, with focus on inhalation powders, were reviewed. The influence of electrostatic charge on the performance of dry powder inhaler formulations in terms of drug content homogeneity, the passage of drug through the inhaler device, drug-carrier adhesion/detachment, and drug deposition on the respiratory airways were discussed. The understanding gained is crucial to improving the safety, quality, and efficiency of the pharmaceutical inhalation products.

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“…The particle beam is produced at the CERN Proton Synchrotron. The CLOUD chamber can be exposed to a 3.5 GeV c −1 positively charged pion (π + ) beam produced by a secondary target of aluminum or copper (Duplissy et al, 2010). The intensity of the particle beam can be varied to cover the full range of ionization in the troposphere, from an ion production rate of about 2 cm −3 s −1 , equivalent to boundary layer levels, to 80 cm −3 s −1 , equivalent to the levels in the free troposphere (Kazil and Lovejoy, 2004;Zhang et al, 2011).…”

Section: The Particle Beammentioning

confidence: 99%

Experimental investigation of ion-ion recombination at atmospheric conditions

Franchin¹,

Ehrhart²,

Leppä³

et al. 2015

Preprint

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Abstract. We present the results of laboratory measurements of the ion-ion recombination coefficient at different temperatures, relative humidities and concentrations of ozone and sulfur dioxide. The experiments were carried out using the Cosmics Leaving OUtdoor Droplets (CLOUD) chamber at CERN, the walls of which are made of conductive material, making it possible to measure small ions. We produced ions in the chamber using a 3.5 GeV c−1 beam of positively-charged pions (π+) from the CERN Proton Synchrotron (PS) and with galactic cosmic rays, when the PS was switched off. The range of the ion production rate varied from 2 to 100 cm−3s−1, covering the typical range of ionization throughout the troposphere. The temperature ranged from −55 to 20 °C, the relative humidity from 0 to 70%, the SO2 concentration from 0 to 40 ppb, and the ozone concentration from 200 to 700 ppb. At 20 °C and 40% RH, the retrieved ion-ion recombination coefficient was (2.3 ± 0.7) × 10−6cm3s−1. We observed no dependency of the ion-ion recombination coefficient on ozone concentration and a weak variation with sulfur dioxide concentration. However, we found a strong dependency of the ion-ion recombination coefficient on temperature. We compared our results with three different models and found an overall agreement for temperatures above 0 °C, but a disagreement at lower temperatures. We observed a strong dependency of the recombination coefficient on relative humidity, which has not been reported previously.

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Penetration of charged particles through metallic tubes

Cited by 16 publications

References 12 publications

Experimental investigation of ion–ion recombination under atmospheric conditions

Experimental investigation of ion–ion recombination under atmospheric conditions

A review of factors affecting electrostatic charging of pharmaceuticals and adhesive mixtures for inhalation

Experimental investigation of ion-ion recombination at atmospheric conditions

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