Jinhan Mo

Tsinghua University | TH · Department of Building Science

Airborne particulate matters (PM) pose serious health threats to the population, and efficient filtration is needed for indoor and vehicular environments. However, there is an intrinsic conflict between filtration efficiency, air resistance, and service life. In this study, a two‐stage electrostatically assisted air (EAA) filtration device is desig...

Organic films were widely found on indoor impermeable surfaces exposed to gaseous organic compounds, but few studies have addressed the film growth details on different indoor substrates. In this study, we observed the topography evolution of phthalic acid ester (PAE) organic films on three impermeable substrates: polished glass (G-P), mirror-polis...

The generation of harmful by-products during photocatalytic oxidation (PCO) of volatile organic compounds (VOCs) is a bottleneck problem for the application of PCO technology in indoor environment. Toluene is a typical VOC found in indoor air. In this work, the by-products at ppb level were studied during PCO decomposition of toluene in a plate-typ...

It was found that there were unwanted by-products in the photocatalytic oxidation (PCO) of indoor ppb-level toluene, a typical volatile organic compound (VOC) in indoor air. However, up to now the control mechanism of the generation of the products has not been clear. In this study we address the problem: a titania-coated glass-plate reactor was ap...

Considering that people spend more than 80% of their time indoors, ambient particulate matter (PM) in the built environment could pose severe environmental health risks to public health. PM sampling, a technique for the enrichment of PM in the air, is essential for ambient PM composition analysis to understand its environmental and health effect. T...

In-situ thermally restorable adsorption films exhibited brilliant performance for indoor volatile organic compounds (VOCs) purification with negligible wind resistance and considerable lifetime. However, the morphology of adsorption films should be restructured for better adsorption kinetics. This study structured adsorption films with submillimete...

Indoor air quality is closely related to human health, and increasing studies have highlighted that poor indoor air quality presents a threat to occupants’ health in office and school buildings. This paper aims to analyze the exposure levels and health effects of indoor air pollutants in office and school buildings in the Yangtze River Delta, China...

Conventional adsorbents and catalysts shaped by granulation or extrusion have high pressure drop and poor flexibility for chemical, energy, and environmental processes. Direct ink writing (DIW), a kind of 3D printing, has evolved into a crucial technique for manufacturing scalable configurations of adsorbents and catalysts with satisfactory program...

Ambient particulate matter (PM) has been identified as the fourth‐ranking risk factor for mortality globally, and efficient ventilation filtration technologies are urgently needed. In most previous trials, however, high filtration efficiency was achieved either at a low face air velocity or at a large pressure drop cost. Here, nine coarse filters w...

The burden of disease attributed to the indoor exposure to sulfur dioxide (SO2), nitrogen dioxide (NO2), ozone (O3), and carbon monoxide (CO) is not clear, and the quantitative concentration–response relationship is a prerequisite. This is a systematic review to summarize the quantitative concentration–response relationships by screening and analyz...

PAEs usually adsorb on indoor surfaces to form organic films, which could be more hazardous after enriching VOCs. Two typical PAEs, DnBP and DEHP, in the film phase, were chosen to explore the enrichment capacity of gaseous toluene, hexanol, and benzyl alcohol in this study. Exposed to gaseous VOCs less than 250 ppb, film-phase DnBP and DEHP could...

Every year, ambient particulate matter (PM) causes more than one million deaths worldwide. Considering that people spend more than 80% of their time indoors, there is an urgent need for efficient air purification in the built environment. Electrostatic forces have been armed with fibrous filters to promote filtration efficiency and avoid large pres...

Indoor radon exposure is thought to be associated with adverse health effect as lung cancer. Lung cancer incidences in China have been the highest worldwide during the past two decades. It is important to quantitively address indoor radon exposure and its health effect, especially in countries like China. In this paper, we have conducted a meta‐ana...

Building Integrated Heat Pipes (BIHP), specifically a novel passive solar house integrated with gravity heat pipes, realizes envelopes with variable thermal properties and makes effective and efficient use of solar energy to reach zero-carbon heating, and can greatly improve the indoor thermal environment in winter. In this paper, an efficient meth...

Exposure to formaldehyde causes a variety of adverse health outcomes, while the distributions of indoor formaldehyde in different building types are still not clear in China. In this study, based on the systematic review of previously published data and Monte Carlo simulation, we assessed geographical and temporal distributions of indoor formaldehy...

The last two decades have witnessed rapid urbanization and economic growth accompanied by severe indoor air pollution of volatile organic compounds (VOCs) in China. However, indoor VOC pollution across China has not been well characterized and documented. This study is a systematic review of field measurements of eight target VOCs (benzene, toluene...

Ambient particulate matter (PM) poses severe environmental health risks to the public globally, and efficient filtration technologies are urgently needed for air ventilation. In this contribution, to overcome the efficiency-resistance trade-off for fibrous filtration, we introduced an electrostatic polydopamine-interface-mediated (e-PIM) filter uti...

The diffusive uptake rate is essential for using passive samplers to measure indoor volatile organic compounds (VOCs). The traditional theoretical model of passive samplers requires available regression formulas of uptake rates and physicochemical properties of adsorbents to predict the uptake rate. However, it is difficult to obtain the uptake rat...

Traditional lightweight building envelopes with constant thermal properties are of small heat capacity and large thermal resistance. Lightweight building envelopes with variable thermal conductivity and variable equivalent specific heat capacity can promote passive solar heat gain for clean heating and improve the indoor thermal environment in wint...

Integrating metal-organic frameworks (MOFs) into electrospun nanofiber filters has become an effective method for improving particle filtration efficiency. This study hypothesized that there is an optimal amount of MOFs that can be integrated into electrospun nanofiber filters to achieve the maximum particle removal efficiency while minimizing the...

Obtaining effective and reliable uptake rates is crucial for applying diffusive samplers in monitoring indoor gaseous pollutants. Diffusive uptake rates are mainly reported for the workplace and environmental monitoring in a short-term exposure (such as 8h) at high concentrations or long-term exposure (such as 7d, 14d) at lower concentrations. Ther...

Exposure to volatile organic compounds (VOCs) indoors is thought to be associated with several adverse health effects. However, we still lack concentration–response (C‐R) relationships between VOC levels in civil buildings and various health outcomes. For this paper, we conducted a systematic review and meta‐analysis of observational studies to sum...

China's profoundly rapid modernization in the past two decades has resulted in dramatic changes in indoor environmental exposures. Among these changes, exposure to phthalates has attracted increasing attention. We aimed to characterize indoor phthalate exposure and to estimate the disease burden attributable to indoor phthalate pollution from 2000...

Indoor air cleaning has been proved to be an efficient way to reduce indoor harmful VOCs. Many advanced technologies have been studied for the quick and economical removal of VOCs from indoor air. This chapter introduced photocatalytic oxidation (PCO) and room-temperature thermal catalytic oxidation (TCO). The principle of PCO was introduced, and t...

Particulate matter (PM) poses a severe health threat to the public, and fibrous filtration is a powerful method for efficient PM removal. Arming the fibers with electrostatic effect is a gold rush to promote PM-fiber interaction, thus reaching high PM removal efficiency, decreasing airflow resistance, and achieving multifunctional applications simu...

Electrostatic assisted air (EAA) coarse filters combine the benefits of electrostatic precipitators and fibrous filters, achieving high filtration efficiency for submicron particulate matters (PM), low pressure drop, and large dust-holding capacity. For application in heating, ventilation, and air conditioning (HVAC) systems, PM removal technology...

Better utilization of renewable energy is necessary to replace fossil fuels to reach low-carbon. Passive solar houses (PSHs) can be much helpful for enhancing indoor thermal comfort by solar energy instead of fossil energy. However, for the existing PSHs, solar energy absorbed by the exterior walls is used inefficiently since the exterior walls pla...

In-situ thermally regenerated flexible adsorption films are superior for long-term purification of indoor low-concentration volatile organic compounds (VOCs). To further improve the adsorption kinetics of the films, the surface morphology of adsorption films was suggested in hierarchical channel structure. However, such structure is far from practi...

Air filters are crucial components of a building ventilation system that contribute to improving indoor air quality, but they are typically associated with relatively high pressure drops. The purpose of the study is to evaluate the effect of additives on ultrathin electrospun filters, the pressure drop, and the particle removal efficiency of unifor...

The molecular mechanisms underlying the associations between air pollution exposure and adverse cardiopulmonary effects remain to be better understood. Altered amino acid metabolism may plays an important role in the development of cardiopulmonary diseases and may be perturbed by air pollution exposure. To test this hypothesized molecular mechanism...

After decades of development, the indoor environment in China has changed. A systematic review was conducted from peer-reviewed scientific papers with field test data of indoor radon in China from 2000 to 2020 for three types of buildings. The mean concentrations of indoor radon for dwellings, school buildings, and office buildings are 54.6, 56.1,...

Nitrated polycyclic aromatic hydrocarbons (nitro-PAHs) have been widely studied for their mutagenic and carcinogenic effects. This study aims to investigate whether exposure to nitro-PAHs is associated with biomarkers of carbohydrate metabolism, an underlying risk factor for metabolic disorder. Early morning urine and blood samples were longitudina...

Air Filtration In article number 2102051, Jinhan Mo, Guiyin Xu, Ju Li, and co-workers develop a two-stage electrostatically assisted air (EAA) filtration device with stage-I plasma charging and stage-II polydopamine coated polyethylene terephthalate (PET) coarse filters. By controlling the surface microstructure of the filters, the authors report a...

Background The COVID-19 pandemic has severely disrupted supply chains for many types of Personal Protective Equipment (PPE), particularly surgical N95 filtering facepiece respirators (FFRs; “masks”). As a consequence, an Emergency Use Authorization (EUA) from the FDA has allowed use of industrial N95 respirators and importation of N95-type masks ma...

Personal protective equipment (PPE) is crucially important to the safety of both patients and medical personnel, particularly in the event of an infectious pandemic. As the incidence of Coronavirus Disease 2019 (COVID-19) increases exponentially in the United States and many parts of the world, healthcare provider demand for these necessities is cu...

Air filtration is of vital importance for creating healthy breathing indoor air. Particle filters can cause relatively high air resistance and large energy consumption in building ventilation systems. Electrostatically assisted metal foam (EAMF) filters have been developed to provide relatively high efficiency with low air resistance. This study re...

In-situ thermally regenerated adsorption is superior for the long-term purification of indoor VOCs. In this study, a concrete mathematical model has been built to predict adsorption behaviors in various practical situations. Parametric analyses, including the influences of adsorption kinetic parameters, face velocity, and geometric parameters, were...

Indoor ammonia (NH3) pollution has been paid more and more attention in view of its health risk. However, few studies have investigated the exposure level in the non‐occupational environment in China. This study systematically reviewed the indoor ammonia exposure level in different regions, the equivalent exposure concentration of different populat...

Ventilation systems are the primary way of eliminating airborne pathogenic particles in an operating room (OR). However, such systems can be complex due to factors such as different surgical instruments, diverse room sizes, various staff counts, types of clothing used, different surgical types and duration, medications, and patient conditions. OR v...

Fine particulate matter (PM2.5) pollution is of national concern in China. Indoor PM2.5 concentrations may contribute significantly to human exposure because people spend most of their time indoors. In this study, we systematically reviewed the level of indoor PM2.5 concentrations in residences, offices, and schools in China. We looked for correspo...

Concerns on nitrated polycyclic aromatic hydro- carbons (nitro-PAHs) in the environment have mainly arisen from their mutagenic and carcinogenic effects. The objective of this study is to investigate whether nitro-PAH exposures are associated with biomarkers of cardiovascular pathophysiology. In a panel study design, urines and blood samples were c...

Given a large fraction of people’s exposure to urban PM2.5 occur indoors, reducing indoor PM2.5 levels may offer a more feasible and immediate way to save substantial lives and economic losses attributable to PM2.5 exposure. We aimed to estimate the premature mortality and economic loss reductions associated with achieving the newly established Chi...

The COVID-19 pandemic has led to widespread shortages of personal protective equipment (PPE) for healthcare workers, including of N95 masks (filtering facepiece respirators; FFRs). These masks are intended for single use but their sterilization and subsequent reuse has the potential to substantially mitigate shortages. Here we investigate PPE steri...

The ongoing COVID-19 epidemic has spread worldwide since December 2019. Effective use of engineering controls can prevent its spread and thereby reduce its impact. As airborne transmission is an important mode of infectious respiratory disease transmission, mathematical models of airborne infection are needed to develop effective engineering contro...

A variety of air filtration technologies are commercially available for reducing particles and gaseous contaminants that may enter buildings from outside. According to the World Health Organization (WHO), there is an increasing range of adverse health effects linked to air pollution, at even-lower concentration of pollutants. This article presents...

Many people spend most of their time in an indoor environment. A positive relationship exists between indoor environmental quality and the health, wellbeing, and productivity of occupants in buildings. The indoor environment is affected by pollutants, such as gases and particles. Pollutants can be removed from the indoor environment in various ways...

Background: Ozone (O3) exposure has been associated with biomarkers of platelet activation and oxidative stress. The metabolism of arachidonic acid (AA) plays an important role in platelet activation and oxidative stress. However, AA metabolic pathways have not been examined in relation to O3 and other air pollutants. Methods: Early morning urin...

Adsorption has been used widely to remove indoor volatile organic compounds (VOCs). However, the large diffusion resistance inside traditional granular adsorbents renders a low VOC adsorption rate. This study proposes a modified method to achieve the rapid diffusion into the adsorbent during the initial adsorption period. A thin and flexible adsorp...

Microbes in buildings have attracted extensive attention from both theresearch community and the general public due to their close relationship with human health. However, there still lacks comprehensive information on the indoor exposure level of microbes in China. This study systematically reviews exposure levels, the community structures, and th...

Negative ion air purifiers (NIAPs), as a less costly alternative to the HEPA filtration, have been increasingly deployed in China and potentially elsewhere. While reducing indoor concentrations of fine particulate matter (PM2.5), NIAPs generate massive amounts of negative ions that may be of health concern. We performed week‐long interventions with...

Background/aim Melatonin is a free radical scavenger and an anti-inflammatory biomolecule. Air pollution exposure has been associated with increased inflammatory responses. We hypothesize that endogenous melatonin plays a role in inflammatory responses to air pollution exposure. Methods We tested this hypothesis in a cohort of 53 healthy adults (2...

Background: During the current COVID-19 pandemic, supply chains for Personal Protective Equipment (PPE) have been severely disrupted and many products, particularly surgical N95 filtering facepiece respirators (FFRs; "masks") are in short supply. As a consequence, an Emergency Use Authorization (EUA) from the FDA has allowed importation of N95-type...

In air filtration for creating healthy indoor air, there is an intrinsic conflict between high filtration efficiency and low wind pressure drop. In this study, we overcame this conflict by developing new dielectric hetero-caking (HC) filters, in which high relative dielectric constant (εr) materials were heterogeneously loaded on the traditional po...

Objective: The COVID-19 pandemic has led to widespread shortages of personal protective equipment (PPE) for healthcare workers, including filtering facepiece respirators (FFRs) such as N95 masks. These masks are normally intended for single use, but their sterilization and subsequent reuse could substantially mitigate a world-wide shortage. Desig...

Importance Fine particles (particulate matter 2.5 μm [PM2.5]), a ubiquitous air pollutant, can deposit in the small airways that play a vital role in asthma. It appears to be unknown whether the use of a PM2.5 filtration device can improve small airway physiology and respiratory inflammation in children with asthma. Objective To discover what path...

The influx of ambient particulate matter (PM) to the indoor environment has threatened human health due to its adverse impacts on respiratory, cardiovascular, and neurological systems. Consequently, PM removal devices with high efficiency and low cost like electrostatic precipitator (ESP) are essential for a healthy and sustainable indoor environme...

Exposure to air pollutants has been associated with respiratory and cardiovascular mortality, but the underlying molecular mechanisms remain inadequately understood. We aimed to examine molecular-level inflammatory and oxidative stress responses to personal air pollutant exposure. Fifty-three healthy adults aged 22–52 were measured three times for...

Influenza transmission occurs through the air, but the relative importance of small droplets, or aerosols, in influenza transmission especially within healthcare facilities remains uncertain. Detections of influenza virus in aerosols in cough and exhaled breath from infected patients, and from the air in outpatient or inpatient healthcare facilitie...

Phthalates are widely used as additives to consumer products. Many diseases have been shown to be related to the uptake of phthalates. To achieve equilibrium constant phthalate generation for mass transfer and exposure experiments, the present study developed a porous media based method using Teflon generators connected to the media with stainless...

High concentration particulate matter (PM) has been a serious environmental problem in China and other developing countries. Electrostatic-based purification technology is a method to remove airborne particles, and can reduce the energy consumption of ventilation fans in buildings because of its low pressure drop. In this study, we developed a new...

Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) and malondialdehyde (MDA) are commonly used biomarkers of oxidative stress. However, their associations with air pollutant exposure have not been consistent across studies. We hypothesize that the inconsistency is partly due to confounding of circulating melatonin. We analyzed urinary 6-sulfatoxymelatoni...

Electrostatically assisted air (EAA) coarse filter can improve the particle filtration performance of low efficiency filters without increasing their pressure drop. In this study, we investigated the long-term single pass filtration efficiency for 0.3 ~ 10 μm ambient particles, pressure drop, PM2.5 collecting amount, and energy consumption of an EA...

Exposure to fine particulate matter (PM 2.5 ) has been associated with lung inflammation and airway hyperresponsiveness (AHR). Transient receptor potential (TRP) vanilloid 1 (TRPV1) and ankyrin 1 (TRPA1) both may play important roles in lung inflammation and AHR. We investigated whether PM 2.5 -induced lung inflammation and AHR could be prevented b...

Semiquinone free radicals (SFRs) exist significantly in ambient particulate matters and threaten human health due to their genotoxicity and stability compared to other radicals. Efficient quantitative detection methods for SFRs on particles are in great need. In this study, we proposed a quantitative detection method for semiquinone free radicals o...

Efficient particle removal technology with minimal pressure drop is urgently needed for both air purification and energy conservation. Compact electrostatically assisted air (cEAA) coarse filters can significantly enhance the filtration efficiency of low-efficiency filters without increasing the pressure drop, thus greatly reducing the energy consu...

This study estimates adult mortalities attributed to PM2.5 across urban China in 2015 and the corresponding mortalities that might be avoided by meeting the yearly-averaged indoor PM2.5 threshold in the newly established Assessment Standard for Healthy Building (ASHB) and seven other potential thresholds. We use outdoor PM2.5 concentrations from ~1...

Formaldehyde is one of the most common indoor air pollutants in Chinese residences. This study introduces a novel laminated plate with adjustable surface temperature to remove gaseous formaldehyde. The plate is fabricated with activated carbon, polyimide and copper foil via thermal compression. The plate can be regenerated in‐situ by applying a dir...

From October 2010 to April 2012, we conducted a cross‐sectional study of associations between household environments and childhood health among preschool children in eight Chinese cities. Here we analyze associations of early household renovation with preterm birth (PTB), low birth weight (LBW), term low birth weight (Term‐LBW), and small for gesta...