Rima Baalbaki
A5055362390- Atmospheric chemistry and aerosols
- Air Quality and Health Impacts
- Atmospheric aerosols and clouds
- Atmospheric Ozone and Climate
- Air Quality Monitoring and Forecasting
- Atmospheric and Environmental Gas Dynamics
- Vehicle emissions and performance
- Species Distribution and Climate Change
- Smoking Behavior and Cessation
- Indoor Air Quality and Microbial Exposure
- Geochemistry and Geologic Mapping
- Radioactivity and Radon Measurements
- Marine and environmental studies
- Climate change and permafrost
- Solar and Space Plasma Dynamics
- Soil Carbon and Nitrogen Dynamics
- Climate variability and models
- Phosphorus and nutrient management
- Smart Agriculture and AI
- Ethics in Clinical Research
- scientometrics and bibliometrics research
- Impact of Light on Environment and Health
- Dark Matter and Cosmic Phenomena
- Particle Dynamics in Fluid Flows
- Industrial Gas Emission Control
University of Helsinki
2018-2024
American University of Beirut
2013-2019
Virginia Commonwealth University
2014-2016
Associated Research (United States)
2016
Journal Article Effects of User Puff Topography, Device Voltage, and Liquid Nicotine Concentration on Electronic Cigarette Yield: Measurements Model Predictions Get access Soha Talih, PhD, PhD 1Department Mechanical Engineering, American University Beirut, Lebanon;2Department Psychology, Center for the Study Tobacco Products, Virginia Commonwealth University, Richmond, VA Search other works by this author on: Oxford Academic PubMed Google Scholar Zainab Balhas, ME, ME Thomas Eissenberg,...
A list of authors and their affiliations appears at the end paper New-particle formation is a major contributor to urban smog1,2, but how it occurs in cities often puzzling3. If growth rates particles are similar those found cleaner environments (1-10 nanometres per hour), then existing understanding suggests that new should be rapidly scavenged by high concentration pre-existing particles. Here we show, through experiments performed under atmospheric conditions CLOUD chamber CERN, below...
Faster than expected Iodine species are one of only a handful atmospheric vapors known to make new aerosol particles, which play central role in controlling the radiative forcing climate. He et al. report experimental evidence from CERN Cosmics Leaving Outdoor Droplets, or CLOUD, chamber demonstrating that iodic acid and iodous rapidly form particles can compete with sulfuric pristine regions. Science , this issue p. 589
Available in hundreds of device designs and thousands flavors, electronic cigarette (ECIG) may have differing toxicant emission characteristics. This study assesses nicotine carbonyl yields the most popular brands U.S. market. These products included disposable, prefilled cartridge, tank-based ECIGs. Twenty-seven ECIG 10 were procured their power outputs measured. The e-liquids characterized for pH, concentration, propylene glycol/vegetable glycerin (PG/VG) ratio, water content. Aerosols...
Atmospheric gas-to-particle conversion is a crucial or even dominant contributor to haze formation in Chinese megacities terms of aerosol number, surface area and mass. Based on our comprehensive observations Beijing during 15 January 2018-31 March 2019, we are able show that 80-90% the mass (PM2.5) was formed via atmospheric reactions days over 65% number concentration particles resulted from new particle (NPF). Furthermore, faster when subsequent growth newly enhanced. Our findings suggest...
Abstract Intense and frequent new particle formation (NPF) events have been observed in polluted urban environments, yet the dominant mechanisms are still under debate. To understand key species governing processes of NPF we conducted comprehensive measurements downtown Beijing during January–March, 2018. We performed detailed analyses on sulfuric acid cluster composition budget, as well chemical physical properties oxidized organic molecules (OOMs). Our results demonstrate that fast...
The mechanistic pathway by which high relative humidity (RH) affects gas–particle partitioning remains poorly understood, although many studies report increased secondary organic aerosol (SOA) yields at RH. Here, we use real-time, molecular measurements of both the gas and particle phase to provide a understanding effect RH on biogenic oxidized molecules (from α-pinene isoprene) low temperatures (243 263 K) CLOUD chamber CERN. We observe increases in SOA mass 45 85% with increasing from...
Abstract. Highly oxygenated organic molecules (HOMs) contribute substantially to the formation and growth of atmospheric aerosol particles, which affect air quality, human health Earth's climate. HOMs are formed by rapid, gas-phase autoxidation volatile compounds (VOCs) such as α-pinene, most abundant monoterpene in atmosphere. Due their abundance low volatility, can play an important role new-particle (NPF) early aerosols, even without any further assistance other low-volatility sulfuric...
Abstract. In the present-day atmosphere, sulfuric acid is most important vapour for aerosol particle formation and initial growth. However, growth rates of nanoparticles (<10 nm) from remain poorly measured. Therefore, effect stabilizing bases, contribution ions impact attractive forces on molecular collisions are under debate. Here, we present precise rate measurements uncharged particles 1.8 to 10 nm, performed atmospheric conditions in CERN (European Organization Nuclear Research)...
As with other tobacco aerosols, nicotine delivery from e-cigarettes (ECIG) depends on the total and its partitioning between free-base (Nic) protonated (NicH(+)) forms. Previous studies of ECIG emissions have generally reported "nicotine yield" without attention to whether methods employed resulted in quantification or only one forms, making results difficult compare across evaluate against blood exposure. This study reports a convenient solvent extraction method for determining liquids...
Abstract. Nucleation of atmospheric vapours produces more than half global cloud condensation nuclei and so has an important influence on climate. Recent studies show that monoterpene (C10H16) oxidation yields highly oxygenated products can nucleate with or without sulfuric acid. Monoterpenes are emitted mainly by trees, frequently together isoprene (C5H8), which the highest emission all organic vapours. Previous have shown suppresses new-particle formation from monoterpenes, but cause this...
Abstract. Gaseous sulfuric acid (H2SO4) is known as one of the key precursors for atmospheric new particle formation (NPF) processes, but its measurement remains challenging. Therefore, a proxy method that able to derive gaseous concentrations from parameters can be measured relatively easily and accurately highly desirable chemistry community. Although such methods are available clean environments, works well in polluted atmosphere, found Chinese megacities, yet developed. In this study,...
Abstract. Sulfuric acid has been shown to be a key driver for new particle formation and subsequent growth in various environments, mainly due its low volatility. However, direct measurements of gas-phase sulfuric are oftentimes not available, the current proxies cannot predict, example, nighttime concentrations or result significant discrepancies with measured values. Here, we define sources sinks different environments derive physical proxy utilized locations during periods when it is...
We use a real-time temperature-programmed desorption chemical-ionization mass spectrometer (FIGAERO–CIMS) to measure particle-phase composition and volatility of nucleated particles, studying pure α-pinene oxidation over wide temperature range (−50 °C +25 °C) in the CLOUD chamber at CERN. Highly oxygenated organic molecules are much more abundant particles formed higher temperatures, shifting compounds toward O/C lower intrinsic (300 K) volatility. find that biogenic nucleation growth...
Abstract. New particle formation (NPF) is a significant source of atmospheric particles, affecting climate and air quality. Understanding the mechanisms involved in urban aerosols important to develop effective mitigation strategies. However, NPF rates reported polluted boundary layer span more than 4 orders magnitude, reasons behind this variability are subject intense scientific debate. Multiple vapours have been postulated participate NPF, including sulfuric acid, ammonia, amines...
Abstract New particle formation in the upper free troposphere is a major global source of cloud condensation nuclei (CCN) 1–4 . However, precursor vapours that drive process are not well understood. With experiments performed under tropospheric conditions CERN CLOUD chamber, we show nitric acid, sulfuric acid and ammonia form particles synergistically, at rates orders magnitude faster than those from any two three components. The importance this mechanism depends on availability ammonia,...
Dimethyl sulfide (DMS) influences climate via cloud condensation nuclei (CCN) formation resulting from its oxidation products (mainly methanesulfonic acid, MSA, and sulfuric H2SO4). Despite their importance, accurate prediction of MSA H2SO4 DMS remains challenging. With comprehensive experiments carried out in the Cosmics Leaving Outdoor Droplets (CLOUD) chamber at CERN, we show that decreasing temperature +25 to −10 °C enhances gas-phase production by an order magnitude OH-initiated...
Biogenic vapors form new particles in the atmosphere, affecting global climate. The contributions of monoterpenes and isoprene to particle formation (NPF) have been extensively studied. However, sesquiterpenes received little attention despite a potentially important role due their high molecular weight. Via chamber experiments performed under atmospheric conditions, we report biogenic NPF resulting from oxidation pure mixtures β-caryophyllene, α-pinene, isoprene, which produces oxygenated...
The main nucleating vapor in the atmosphere is thought to be sulfuric acid (H2SO4), stabilized by ammonia (NH3). However, marine and polar regions, NH3 generally low, H2SO4 frequently found together with iodine oxoacids [HIOx, i.e., iodic (HIO3) iodous (HIO2)]. In experiments performed CERN CLOUD (Cosmics Leaving OUtdoor Droplets) chamber, we investigated interplay of HIOx during atmospheric particle nucleation. We that greatly enhances H2SO4(-NH3) nucleation through two different...
Abstract. To quantify the contribution of new particle formation (NPF) to ultrafine number and cloud condensation nuclei (CCN) budgets, one has understand mechanisms that govern NPF in different environments its temporal extent. Here, we study Cyprus, an Eastern Mediterranean country located at crossroads three continents affected by diverse air masses originating from continental, maritime, desert-dust source areas. We performed 1-year continuous measurements aerosol particles down ∼ 1 nm...
Abstract Iodine is a reactive trace element in atmospheric chemistry that destroys ozone and nucleates particles. emissions have tripled since 1950 are projected to keep increasing with rising O 3 surface concentrations. Although iodic acid (HIO ) widespread forms particles more efficiently than sulfuric acid, its gas-phase formation mechanism remains unresolved. Here, CLOUD simulation chamber experiments generate iodine radicals at atmospherically relevant rates, we show iodooxy hypoiodite,...
<h3>Significance</h3> The wide availability of sweet flavours has been hypothesised as a factor in the popularity electronic cigarette (ECIG), especially among youth. Saccharides, which are commonly used to impart flavour ECIG liquids, thermally degrade produce toxic compounds, like aldehydes and furans. This study investigates formation furanic compounds aerosols when liquid solutions varying sweetener concentrations vaped under different power puff duration. <h3>Methods</h3> Liquids...