Publications by authors named "Naiping Gao"

Nicotine is a dependence-producing component in electronic cigarettes. The nicotine release characteristics of electronic cigarettes are closely connected with human exposure and respiratory health. In this paper, a theoretical model was established to study the effects of the compositions of e-liquids and the heating powers of device on the emission and gas/particle partitioning characteristics of nicotine in aerosols at equilibrium.

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Light-induced heat transfer process of plasmonic nanofluids is critical for many applications, but the energy conversion pathway still remains controversial. In this work, we develop a calculation model based on the combination of the electromagnetic theory and molecular dynamics (MD) simulation to investigate the impact of the localized surface plasmon resonance (LSPR) on the heat transfer between nanoparticles and the surrounding medium in gold and silver nanofluids. It is found that the LSPR-induced enhanced electric field (EEF) can obviously reduce the interfacial thermal resistance to promote the heat transfer process, especially in silver nanofluids.

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A mathematical model based on heat and mass transfer processes in the porous wick of electronic cigarettes was established to describe the atomization of e-liquids according to max liquid temperature, vaporization rate and thermal efficiency in a single puff. Dominant capillary-evaporation effects were defined in the model to account for the effects of electrical power, e-liquid composition and porosity of the wick material on atomization and energy transmission processes. Liquid temperature, vaporization rate, and thermal efficiency were predicted using the mathematical model in 64 groups, varying with electrical power, e-liquid composition and wick porosity.

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The aerosols generated from electronic cigarettes have a significant impact on the human respiratory system. Understanding the vaporization characteristics and aerosol optical properties of electronic cigarettes is important for assessing human exposure to aerosols. An experimental platform was designed and built to simulate the atomization process of electronic cigarette and detect the laser transmissivity of aerosols.

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The solar radiation can heat the building outer surface, and then cause the upward natural convection flows adjacent to the wall. This phenomenon is especially obvious on a windless sunny day. The near wall thermal plume can drive gaseous pollutants released from lower floors to upper floors.

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The pollutant behavior in and around a naturally ventilated building requires to be investigated quantitatively as the growing concern on air quality within the built environment. The objective of the present study is to further investigate the wind induced inter-flat pollutant transmission and cross contamination routes in typical buildings in Shanghai. In this paper, a set of experiments was carried out in a boundary layer wind tunnel using a 1:30 reduced scale model that represented the typical configuration of rectangular multi-storey residential buildings.

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The inter-flat dispersion of hazardous air pollutants in residential built environment has become a growing concern, especially in crowed urban areas. The purpose of present study is to investigate the wind induced air pollutant transmission and cross contamination routes in typical buildings. In this paper, a series of experiments was carried out in a boundary layer wind tunnel using a 1:30 scaled model that represented the typical configuration of rectangular multi-storey residential buildings in Shanghai.

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The inter-flat airborne cross-transmission driven by single-sided natural ventilation has been identified recently in high-rise residential buildings, where most people live now in densely populated areas, and is one of the most complex and least understood transport routes. Given potential risks of infection during the outbreak of severe infectious diseases, the need for a full understanding of its mechanism and protective measures within the field of epidemiology and engineering becomes pressing. This review paper considers progress achieved in existing studies of the concerned issue regarding different research priorities.

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Existed evidences show that airborne transmission of human respiratory droplets may be related with the spread of some infectious disease, such as severe acute respiratory syndrome (SARS) and H1N1 pandemic. Non-pharmaceutical approaches, including ventilation system and personal protection, are believed to have certain positive effects on the reduction of co-occupant's inhalation. This work then aims to numerically study the performances of mouth covering on co-occupant's exposure under mixing ventilation (MV), under-floor air distribution (UFAD) and displacement ventilation (DV) system, using drift-flux model.

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Article Synopsis
  • The study looked at how tiny droplets from people could spread in an office when two workers used a special ventilation device called a round movable panel (RMP).
  • Three different methods of air circulation were tested to see which worked best to keep the air clean.
  • It was found that the special device could help reduce the spread of small particles in the air, but sometimes it could also make things worse depending on how much airflow it created.
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It is known that the person-to-person spreading of certain infectious diseases is related with the transmission of human exhaled air in the indoor environments, and this is suspected to be the case with the severe acute respiratory syndrome (SARS) outbreak. This paper presents the numerical analysis of the human respiration process and the transport of exhaled air by breathing, sneezing, and coughing and their potential impact on the adjacent person in a modeled room with displacement ventilation. In order to account for the influence of the thermal plume around the human body, a three-dimensional computational thermal manikin (CTM) with an accurate description of body geometry was applied.

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