A5011713899- Atmospheric chemistry and aerosols
- Air Quality and Health Impacts
- Atmospheric Ozone and Climate
- Air Quality Monitoring and Forecasting
- Vehicle emissions and performance
- Advanced Chemical Physics Studies
- Spectroscopy and Laser Applications
- Catalytic Processes in Materials Science
- Semiconductor Quantum Structures and Devices
- Indoor Air Quality and Microbial Exposure
- Fluorine in Organic Chemistry
- Atmospheric aerosols and clouds
- Toxic Organic Pollutants Impact
- Chemical Synthesis and Analysis
- Mass Spectrometry Techniques and Applications
- Advancements in Semiconductor Devices and Circuit Design
- Anesthesia and Sedative Agents
- Odor and Emission Control Technologies
- Catalysis and Oxidation Reactions
- Carbohydrate Chemistry and Synthesis
- Neuroscience of respiration and sleep
- Spectroscopy and Quantum Chemical Studies
- GaN-based semiconductor devices and materials
- X-ray Diffraction in Crystallography
- Veterinary Pharmacology and Anesthesia
National Institute for Environmental Studies
2015-2025
University of Toyama
2019-2024
Hamamatsu University School of Medicine
2023
Prince Charles Hospital
2021-2022
The University of Queensland
2021-2022
Iwate University
2001-2021
Kyoto University
2012-2019
Teikyo University
2017-2018
University of Yamanashi
2016-2018
Takeda (Japan)
2018
Poor air quality is globally the largest environmental health risk. Epidemiological studies have uncovered clear relationships of gaseous pollutants and particulate matter (PM) with adverse outcomes, including mortality by cardiovascular respiratory diseases. Studies impacts aerosols are highly multidisciplinary a broad range scales in space time. We assess recent advances future challenges regarding aerosol effects on from molecular to global through epidemiological studies, field...
The photooxidation of toluene is a potential source secondary organic aerosol (SOA) in urban air, but only small portion the compounds present SOA have been identified. In this study, we analyzed chemical compositions produced by photoirradiation toluene/NOx/air system laboratory chamber experiments combination liquid chromatography-mass spectrometry, hybrid high-performance and iodometry-spectrophotometry. dependence composition on initial NOx concentration was examined at NO concentrations...
It has recently been suggested that some organic aerosols can absorb solar radiation, especially at the shorter visible and UV wavelengths. Although quantitative characterization of optical properties secondary (SOAs) is required in order to confirm effect SOAs on atmospheric radiation balance, light absorption not yet thoroughly investigated. In this study, we conducted laboratory experiments measure generated during photooxidation toluene presence NO x ozonolysis α ‐pinene. Extinction...
Abstract. Recently, secondary organic aerosols (SOAs) generated from anthropogenic volatile compounds have been proposed as a possible source of light-absorbing compounds, "brown carbon," in the urban atmosphere. However, atmospheric importance these SOAs remains unclear due to limited information about their optical properties. In this study, complex refractive index (RI, m = n-ki values at 405, 532, and 781 nm during photooxidation toluene (toluene-SOAs) under variety initial nitrogen...
Abstract. Oxygenated organic aerosol (OOA) observed in remote areas is believed to comprise aged secondary (SOA); however, the reaction processes relevant SOA chemical aging have hitherto been unclear. We recently measured mass spectra of formed from photooxidation aromatic hydrocarbons using an Aerodyne spectrometer (AMS) and reported that slowed with increasing number alkyl groups precursor molecule. In this study, we selected benzene 1,3,5-trimethylbenzene (TMB) as precursors analyze...
Water-soluble organic nitrogen (WSON) affects the formation, chemical transformations, hygroscopicity, and acidity of aerosols as well biogeochemical cycles nitrogen. However, large uncertainties exist in origins formation processes WSON. Submicrometer aerosol particles were collected at a suburban forest site Tokyo summer 2015 to investigate relative impacts anthropogenic biogenic sources on WSON formations their linkages with liquid water (ALW). The concentrations (ave. 225 ± 100 ngN m–3)...
Abstract. SOA formation from benzene, toluene, m-xylene, and their corresponding phenolic compounds were investigated using the UCR/CE-CERT Environmental Chamber to evaluate importance of as intermediate species in aromatic formation. yield measurements coupled gas-phase indicate that approximately 20% m-xylene could be ascribed route under low NOx conditions. The densities tend initially high 1.8 g cm−3 eventually reach range 1.3–1.4 cm−3. final density was found independent elemental ratio...
Isoprene is globally the most ubiquitous nonmethane hydrocarbon. The biogenic emission found in abundance and has a propensity for SOA formation diverse climates. It important to characterize isoprene with varying reaction temperature. In this work, effect of temperature on formation, physical properties, chemical nature probed. Three experimental systems are probed effects from isoprene, NO + H2O2 photo-oxidation, only dark ozonolysis. These experiments show that readily forms unseeded...
Anthocyanins, sugars, and organic acids contribute to the appearance, health benefits, taste of strawberries. However, their spatial distribution in ripe fruit has been fully unrevealed. Therefore, we performed matrix-assisted laser desorption/ionization, MALDI-IMS, analysis investigate The detection sensitivity was improved by using TM-Sprayer for matrix application. In receptacle, pelargonidins were distributed skin, cortical, pith tissues, whereas cyanidins delphinidins slightly localized...
Because emission rates of particulate matter (PM) from stationary combustion sources have been measured without dilution or cooling in Japan, condensable PM has not included Japanese inventories. In this study, we modified an inventory to include based on the recent surveys using a method. As result, organic aerosol (OA) increased by factor 7 over Japan. Stationary industrial and energy sectors became largest contributors OA emissions Japan revised estimates (filterable-plus-condensable PM),...
Abstract. Secondary organic aerosols (SOAs) affect human health and climate change prediction; however, the factors (e.g., temperature, acidity of pre-existing particles, oxidants) influencing their formation are not sufficiently resolved. Using a compact chamber, temperature dependence SOA yields chemical components in from α-pinene ozonolysis were systematically investigated under 278, 288, 298 K temperatures using neutral ((NH4)2SO4) acidic (H2SO4+((NH4)2SO4)) seed aerosols. with m/z less...
This paper reports the long term observation of particle-associated polycyclic aromatic hydrocarbons (PAHs) at Cape Hedo Atmosphere and Aerosol Monitoring Station, a remote site in Western Pacific Ocean, from 2008 to 2015. is first long-term study that evaluated contribution long-range transport PAHs East Asia. No obvious trend (P > 0.05) was found particular season over years. However, there are seasonal variations PAH concentrations with higher spring winter. The attributed air masses area...
To estimate the sources of polycyclic aromatic hydrocarbons (PAHs) and their contributions to total PAH emissions, more than 40 PAHs organic tracers in PM2.5 collected 3 cities Japan were measured a positive matrix factorization (PMF) model analysis was performed. During warm season, high concentrations detected Nagoya, which is located port area. Total classified into five sources: biomass combustion, semivolatile PAHs, ship industrial major, road traffic plastic minor. Analysis emissions...
Blue-flowered gentian (Gentiana triflora) is known to accumulate gentiodelphin, a unique polyacylated delphinidin-type anthocyanin, in the petals. Almost all of structural genes involved gentiodelphin biosynthesis have been isolated, but an important gene encoding UDP-glucose:anthocyanin 5-O-glucosyltransferase (5GT) remained be identified. In this study, attempt was made isolate and characterize 5GT, which responsible for glucosylation anthocyanidin 3-glucoside. A PCR-based cloning strategy...
Recent field and laboratory studies suggest that forest aerosol particles contain more highly functionalized organic molecules than pinonic acid, a traditional molecular maker of secondary (SOA) particles. To investigate the reaction mechanisms during aging biogenic SOAs, gases formed from ozonolysis β- α-pinene were exposed to OH radicals in chamber. The particle samples collected before after exposure for analysis by liquid chromatography-negative electrospray ionization time-of-flight...
Abstract We report the first measurements of complex refractive index (RI) at 375, 405, 532, and 781 nm for secondary organic aerosol (SOA) generated from isoprene/NO x photooxidation. At all wavelengths studied, slightly greater real components RI were observed SOA in absence SO 2 compared with those its presence. Considering chemical properties, differences oxidation state and/or ratio particle density to molecular weight compounds are considered be main factors determining components. The...