PhD / Electrostatics of aerosols for inhalation is a relatively new research area. Charge properties of these particles are largely unknown but electrostatic forces have been proposed to potentially influence lung deposition. Investigation on the relationship between formulation and aerosol charging is required to understand the fundamental mechanisms. A modified electrical low pressure impactor was employed to measure the particles generated from metered dose inhalers and dry powder inhalers. This equipment provides detailed size and charge information of the aerosols. The particles were sized by impaction onto thirteen stages. The net charges in twelve of the size fractions were detected and recorded by sensitive electrometers. The drug deposits were quantified by chemical assay. The aerosol charge profiles of commercial metered dose inhalers were product-dependent, which was due to differences in the drug, formulation, and valve stem material. The calculated number of elementary charges per drug particle of size ≤ 6.06 μm ranged from zero to several ten thousands. The high charge levels on particles may have a potential effect on the deposition of the aerosol particles in the lung when inhaled. New plastic spacers marketed for use with metered dose inhalers were found to possess high surface charges on the internal walls, which was successfully removed by detergent-coating. Detergent-coated spacer had higher drug output than the new ones due to the reduced electrostatic particle deposition inside the spacer. Particles delivered from spacers carried lower inherent charges than those directly from metered dose inhalers. Those with higher charges might be susceptible to electrostatic forces inside the spacers and were thus retained. The electrostatic low pressure impactor was further modified to disperse two commercial Tubuhaler® products at 60 L/min. The DPIs showed drug-specific responses to particle charging at different RHs. The difference in hygroscopicity of the drugs may play a major role. A dual mechanistic charging model was proposed to explain the charging behaviours. The charge levels on drug particles delivered from these inhalers were sufficiently high to potentially affect deposition in the airways when inhaled. Drug-free metered dose inhalers containing HFA-134a and 227 produced highly variable charge profiles but on average the puffs were negatively charged, which was thought to be due to the electronegative fluorine atoms in the HFA molecules. The charges of both HFAs shifted towards neutrality or positive polarity with increasing water content. The spiked water might have increased the electrical conductivity and/or decreased the electronegativity of the bulk propellant solution. The number of elementary charges per droplet decreased with decreasing droplet size. This trend was probably due to the redistribution of charges amongst small droplets following electrostatic fission of a bigger droplet when the Raleigh limit was reached.

This thesis seeks to simulate the impact on the human foot on the car bumper. The opening section deals with requirements as to the current passive safety features aiming to mitigate the consequences of such impact. The thesis also describes the construction of a human foot impactor, its certification via both static and dynamic tests, a simulation of the cash test and its evaluation. The designed model as well as the simulation procedure have been led according to the current Euro NCAP specifications.

The focus of this master’s thesis is the issue of fine dust particles suspended in the air and their measurement. The thesis explains the basic characteristics of fine particles and the rules, which they follow. The section then examines the health risks of inhaled particles. Next is explained the influence of particles in the air on the environment, the historical development of the air pollution in the Czech Republic and the most important pollutants. After that is described the legislation, which frames the limits for pollutants suspended in the air. In the practical part is described the methods for calculation the geometry of cascade impactor, the design of three-stage impactor and finally the comparison with professional impactor. The designed impactor was then constructed and tested with wood burning stove as a source of particles.

The thesis describes the complex of basic testing procedures conducted by Euro NCAP company with a view to the examination of pedestrian protection in accordance with EEVC WG 17 and topical instruments used at passenger vehicles for pedestrian protection. It includes a detailed procedure of the creation of an adult head impactor including its certification and the formation of its impact on the bonnet of the vehicle. It is specialized in the studies how material properties influence the size of HIC criterion.

This thesis deals with the subject of crash tests Euro NCAP, concretely child-head impact test to the car bonnet. Object of thesis is make homogeneous car bonnet, where will remove stiffness places and also the bonnet global stiffness won´t be worst. The bonnet must carry out limits for pedestrian protection.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第20375号 / 工博第4312号 / 新制||工||1668(附属図書館) / 京都大学大学院工学研究科電気工学専攻 / (主査)教授 山川 宏, 教授 引原 隆士, 准教授 海老原 祐輔 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

<p> A virtual impactor type dust flow concentrator was developed and an experimental investigation was performed to characterize the hydraulic and particulate matter (PM) separation performance of the device. In particular, the pressure drop characteristics, the ratio of the flow through the two branches, and the PM concentration in the minor and main branch of the flow concentrator were evaluated using experiments on a diesel exhaust rig and an air rig. Tests were performed to examine the effect of the inlet flow Reynolds number, the inlet tube lip position relative to the concentration probe, and the flow distribution between the minor and main branches. Numerical simulations were also performed for a simplified concentrator geometry to examine the flow streamlines and pressure drop. The results showed that the ratio of the concentration in the minor and main flow branches changed as the flow rate in these branches changed, reaching a maximum at a minor flow ratio that depended on the lip position. It was observed the difference of the particulate matter concentration in the minor and main branch was greater for higher inlet Reynolds number. For example, the concentration ratio increased 50% as the Reynolds number increased from 2,200 to 25,700. A similar result was observed when the inlet tube lip was moved further into the concentration body. The pressure losses seem to be mainly caused by the changes in flow directions and the change in the cross sectional areas.</p> / Thesis / Master of Applied Science (MASc)

Ballistic shields are used by defense teams in dangerous situations as protection against threats such as gunfire. When a ballistic shield is struck, the shield material will deform to absorb the kinetic energy of the incoming projectile. The rapid back-face deformation of the shield can contact the arm, which can impart a large force over an extremely short duration. This work modified an Anthropomorphic Test Device (ATD) to be used for the characterization of behind ballistic shield blunt impact loading profiles. The modified ATD was instrumented to measure impacts at the hand, wrist, forearm, and elbow to compare the force transfer at different locations of impact. A custom jig was designed to support the ATD behind a ballistic shield, provide a high degree of adjustability, and be subjected to impact testing. Two ballistic shield models, both with the same protection rating, were tested and showed to have statistically different responses to the same impact conditions, indicating further need for shield safety evaluation. To apply these loading profiles to future injury criteria development tests, a pneumatic impacting apparatus was re-designed that will allow the high energy impact profiles to be re-created in the McMaster Injury Biomechanics lab. Understanding the ballistic impact conditions, as well as the response of different ballistic shield models provided insight into the possible methods available to reduce upper extremity injury risk. This work has provided essential data for informing a future standard for shield safety evaluation. / Thesis / Master of Applied Science (MASc) / When a ballistic shield is impacted by a bullet it deforms to absorb the incoming energy. The high-speed deformation of the shield material can impact the arm leading to fracture and possible life-threatening risks if the shield is dropped due to this injury. At the time of this work, there were no standards that limited the amount of allowable back-face deflection or tools available that could measure the force transferred to the arm in this scenario. The purpose of this work was to develop a measurement device that could measure the force transferred to the arm from the behind shield impact. An existing crash test dummy arm was modified to provide measurement capabilities for this loading scenario. Ballistic shield testing was conducted where two different ballistic shield models were impacted to observe how the impact force changed with shield design, as well as the distance the device was placed behind the shield. A pneumatic impacting apparatus was then re-designed in the McMaster Injury Biomechanics lab that will allow the ballistic impact conditions to be re-created for evaluating the injury tolerance of the arm. The results of this work will be used to inform the future development of a ballistic shield evaluation standard.

This investigation examines the effects of load, speed, exhaust gas recirculation (EGR) level and hydrogen addition level on the exhaust gas emissions, particulate matter size distribution and chemical composition. The experiments were performed on a 2.0 litre, 4 cylinder, direct injection engine. EGR levels were then varied from 0% to 40%. Hydrogen induction was varied between 0 and 10% vol. of the inlet charge. In the case of using hydrogen and EGR, the hydrogen replaced air. The load was varied from 0 to 5.4 bar BMEP at two engine speeds, 1500 rpm and 2500 rpm. For this investigation the carbon monoxide (CO), total unburnt hydrocarbons (THC), nitrogen oxides (NOX) and the filter smoke number (FSN) were all measured. The in-cylinder pressure was also captured to allow the heat release rate to be calculated and, therefore, the combustion to be analysed. A gravimetric analysis of the particulate matter size distribution was conducted using a nano-MOUDI. Finally, a GC-MS was used to determine the chemical composition of the THC emissions. The experimental data showed that although CO, FSN and THC increase with EGR, NOX emissions decrease. Inversely, CO, FSN and THC emissions decrease with hydrogen, but NOX increases. When hydrogen was introduced the peak cylinder pressure was increased, as was the maximum rate of in-cylinder pressure rise. The position of the peak cylinder pressure was delayed as hydrogen addition increased. This together with the obtained heat release patterns shows an increase in ignition delay, and a higher proportion of premixed combustion. The experimental work showed that the particulate matter size distribution was not dramatically altered by the addition of EGR, but the main peak was slightly shifted towards the nucleation mode with the addition of hydrogen. Hydrogen addition does not appear to have a large effect on the chemical composition of the THC, but does dramatically decrease the emissions.

Aerosol electrostatics is an important property of pharmaceutical aerosols. The electrostatic properties of pMDI aerosols have been shown to be a function of both formulation and packaging components. The modified ELPI enables measurement of aerosol charge as a function of particle size, and the simultaneous determination of the mass distribution using chemical analysis. However, in order to fully assess the cause and effects of aerosol electrostatics in terms of its biological and regulatory implications, it is necessary to understand the basic charging mechanisms inside the pMDI formulation. Electrical resistivity and zeta potential measurements confirmed the presence of charged species within HFA based solutions and suspensions although the nature of these species remains unknown. These measurements were influenced by the cosolvent concentration and to a lesser extent by the presence of soluble drug and surfactant. The mean electrical resistivity of a 7% ethanol / 93% HFA 134a blend (0.83 ± 0.02 MΩ.cm) was significantly lower than that reported for HFA 134a (180 MΩ.cm). Albuterol sulfate demonstrated a positive zeta potential (75.9 ± 26.2 mV) in HFA 134a. Pilot molecular modeling studies, in conjunction with the analysis of particle interactions using HINT, provided an improved understanding of the possible interactions within albuterol sulfate HFA suspension pMDIs. The predominantly negative (-7597 ± 2063) HINT score signified unfavorable interactions between albuterol sulfate and HFA 134a molecules. Systematic investigations of the electrical properties of HFA solution and suspension pMDIs using the modified ELPI demonstrated that the electrical properties were a function of the formulation type (solution/suspension), formulation components and particle size. Experimental BDP solution pMDIs produced predominantly electropositive aerosols (net charge: 160 ± 30 pC) while albuterol sulfate pMDIs produced bipolar charged aerosol clouds (net charge: -162 ± 277 pC). Finally, the modified ELPI was recalibrated using commercially available polydisperse pMDIs as calibration aerosols with a reference Andersen cascade impactor. The mean cut-off diameters for stages 4-12 obtained following recalibration of the modified ELPI were 0.44, 0.56, 0.70, 1.01, 1.40, 2.12, 3.03, 4.75, 6.37 μm, respectively in comparison to those reported by the manufacturer (0.16, 0.27, 0.39, 0.62, 0.96, 1.62, 2.42, 4.05, 6.67 μm, respectively).