Particle number, mass, and black carbon emissions from fuel-operated auxiliary heaters in real vehicle use

Fuel-operated auxiliary heaters (AHs) are frequent solutions to heat the vehicle engines and cabins in cold areas. Particulate exhaust emissions of AHs are unregulated; therefore, their contribution to local air quality and thus human health and even the global emissions budget is unknown. Experiments for studying the AH-originated emissions were performed under Finnish winter conditions mimicking real-world use for six selected vehicles with original AHs installed, including both gasoline- and diesel-powered heaters. We present quantitative results of particle number emissions down to 1.3 nm, particle size distributions, particulate mass, and black carbon, and compare to gaseous emissions. The start-up and shutdown phases showed the highest particle peaks, while the particle concentrations were stable between these. The mean particle number, mass and BC emission factors were found to be as high as 590 × 1012 kgfuel−1, 33 mg kgfuel−1 and mg 18 kgfuel−1 for gasoline-operated heaters and 560 × 1012 kgfuel−1, 20 mg kgfuel−1 and 12 mg kgfuel−1 for diesel-operated heaters. Comparing total number of particles larger than 23 nm emitted during vehicle preheating with AH to vehicle tailpipe emissions during drive shows that a typical heating cycle emits an equal number of particles to drive dozens or even thousands of kilometers.publishedVersionPeer reviewe

Lääkärien päivystysmallien kehittämis- ja arviointitutkimus - Päivystysmallit ja työkuormitus

Tutkimushankkeen n:o 112241 loppuraportti Työsuojelurahastoll

Engine preheating under real-world subfreezing conditions provides less than expected benefits to vehicle fuel economy and emission reduction for light-duty vehicles

Six light-duty vehicles, both gasoline- and diesel-fueled, were driven a prescribed 13.8 km route in a real-world low-traffic environment under Finnish subfreezing winter conditions (−28. −10 °C). Cold starts, hot starts, and starts with different preheating strategies were used. Fuel consumption and emissions of particles and nitrogen oxides (NOx) were examined by a chasing method with a mobile laboratory. Both electric preheaters (0.3–1.2 kW) and fuel-operated auxiliary heaters (5 kW) were used in the experiments where a cold engine was preheated before starting. While most vehicles showed potential for reducing fuel consumption and emissions of particles (PM), black carbon (BC), and NOx during hot starts compared to subfreezing-cold starts, the benefits of preheating were relatively small and limited to only a few vehicles. The fuel consumption for the 13.8 km drive decreased less than 4% with one gasoline vehicle and one diesel vehicle by preheating. These two vehicles are both equipped with a fuel-operated auxiliary heater, and taking the fuel consumption of the heater during preheating into account leads to about 30% higher total fuel consumption, canceling the preheating benefit out. These two vehicles also showed the largest reductions in PM, BC, and NOx emissions achieved with preheating, e.g., the PM emission reductions being 72% (the gasoline vehicle) and 24% (the diesel vehicle). Whereas the NOx emission reduction for this gasoline vehicle was 41% when considering only the drive, it decreases to 15% when the NOx emissions from the auxiliary heater during preheating are also taken into account. High particle number (PN) emissions from all vehicles and NOx emissions from the diesel vehicles were detected. The PN emissions of particles larger than 23 nm were up to 2 orders of magnitude higher and the NOx emissions up to a factor of 21 higher than the corresponding limits in the European regulations for type-approval of new vehicles. The PN emissions did not depend on the start types; thus, no benefits to reduce them with preheating were detected. The limit-exceeding PN emissions are partially explained with the used measurement method for PN taking both nonvolatile and semivolatile particles into account, whereas the regulations take only the nonvolatile particles into account. The PM emissions were also observed to consist mostly of semivolatile material in most of the cases, organics being the main component of the semivolatile material.Peer reviewe

Kovakuoriaisten maakuntaluettelo 2015

201

HELIOS/SICRIT/mass spectrometry for analysis of aerosols in engine exhaust

Current legislations typically characterize systems of aerosols, such as from vehicle exhaust, primarily by number concentration and size distributions. While potential health threats have a dependence on the particle size, the chemical composition of particles, including the volatile and semi-volatile components adsorbed onto nonvolatile particle cores present at roadside and urban settings, is important in understanding the impact of exhaust particles on health. To date, the only tools suitable for an online in-depth chemical aerosol characterization are aerosol mass spectrometers, which are typically composed of complex and cost intensive instrumentation. We present a new analytical system, which combines a novel inexpensive infrared-radiation-based evaporation system (HELIOS) with a commercially available highly efficient atmospheric ionization source (SICRIT) connected to a rather low-price ion-trap mass spectrometer. Our inexpensive, robust and mobile aerosol characterization HELIOS/SICRIT/Mass Spectrometry system enables highly sensitive chemical analysis of particle-associated volatile substances. We validate the HELIOS/SICRIT/Mass Spectrometry system in laboratory experiments with coated particles generated under controlled conditions, and show that the system is capable of identification of combustion-generated polycyclic aromatic hydrocarbons and relative quantification of individual chemical species adsorbed on particle surfaces. We then employ our system to analyze real-world vehicle engine exhaust aerosol and show through time-resolved measurements with high time resolution (<10 s) that the chemical composition of the particles changes during different parts of an engine test cycle.acceptedVersionPeer reviewe

Antiviral Properties of Chemical Inhibitors of Cellular Anti-Apoptotic Bcl-2 Proteins

Viral diseases remain serious threats to public health because of the shortage of effective means of control. To combat the surge of viral diseases, new treatments are urgently needed. Here we show that small-molecules, which inhibit cellular anti-apoptotic Bcl-2 proteins (Bcl-2i), induced the premature death of cells infected with different RNA or DNA viruses, whereas, at the same concentrations, no toxicity was observed in mock-infected cells. Moreover, these compounds limited viral replication and spread. Surprisingly, Bcl-2i also induced the premature apoptosis of cells transfected with viral RNA or plasmid DNA but not of mock-transfected cells. These results suggest that Bcl-2i sensitizes cells containing foreign RNA or DNA to apoptosis. A comparison of the toxicity, antiviral activity, and side effects of six Bcl-2i allowed us to select A-1155463 as an antiviral lead candidate. Thus, our results pave the way for the further development of Bcl-2i for the prevention and treatment of viral diseases.Peer reviewe

A molecular-based identification resource for the arthropods of Finland

Publisher Copyright: © 2021 The Authors. Molecular Ecology Resources published by John Wiley & Sons Ltd.To associate specimens identified by molecular characters to other biological knowledge, we need reference sequences annotated by Linnaean taxonomy. In this study, we (1) report the creation of a comprehensive reference library of DNA barcodes for the arthropods of an entire country (Finland), (2) publish this library, and (3) deliver a new identification tool for insects and spiders, as based on this resource. The reference library contains mtDNA COI barcodes for 11,275 (43%) of 26,437 arthropod species known from Finland, including 10,811 (45%) of 23,956 insect species. To quantify the improvement in identification accuracy enabled by the current reference library, we ran 1000 Finnish insect and spider species through the Barcode of Life Data system (BOLD) identification engine. Of these, 91% were correctly assigned to a unique species when compared to the new reference library alone, 85% were correctly identified when compared to BOLD with the new material included, and 75% with the new material excluded. To capitalize on this resource, we used the new reference material to train a probabilistic taxonomic assignment tool, FinPROTAX, scoring high success. For the full-length barcode region, the accuracy of taxonomic assignments at the level of classes, orders, families, subfamilies, tribes, genera, and species reached 99.9%, 99.9%, 99.8%, 99.7%, 99.4%, 96.8%, and 88.5%, respectively. The FinBOL arthropod reference library and FinPROTAX are available through the Finnish Biodiversity Information Facility (www.laji.fi) at https://laji.fi/en/theme/protax. Overall, the FinBOL investment represents a massive capacity-transfer from the taxonomic community of Finland to all sectors of society.Peer reviewe

Antiviral properties of chemical inhibitors of cellular anti-apoptotic Bcl-2 proteins

Viral diseases remain serious threats to public health because of the shortage of effective means of control. To combat the surge of viral diseases, new treatments are urgently needed. Here we show that small-molecules, which inhibit cellular anti-apoptotic Bcl-2 proteins (Bcl-2i), induced the premature death of cells infected with different RNA or DNA viruses, whereas, at the same concentrations, no toxicity was observed in mock-infected cells. Moreover, these compounds limited viral replication and spread. Surprisingly, Bcl-2i also induced the premature apoptosis of cells transfected with viral RNA or plasmid DNA but not of mock-transfected cells. These results suggest that Bcl-2i sensitizes cells containing foreign RNA or DNA to apoptosis. A comparison of the toxicity, antiviral activity, and side effects of six Bcl-2i allowed us to select A-1155463 as an antiviral lead candidate. Thus, our results pave the way for the further development of Bcl-2i for the prevention and treatment of viral diseases.</p

Characterization of physical and chemical properties of particulate emissions of a modern diesel-powered tractor with PEMS-measurements

Dieselkäyttöisten ajoneuvojen päästöistä aiheutuu vuosittain merkittävä määrä kuolemia, terveysongelmia ja rahallisia tappioita. Päästölainsäädäntöä ja ajoneuvojen tyyppihyväksyntätestausta tiukennetaan jatkuvasti. Testeissä jätetään kuitenkin huomiotta alle 23 nm kiinteät hiukkaset, kaasumaisista päästöistä pakokaasun laimentuessa muodostuvat hiukkaset ja ilmakehässä tapahtuvan hapettumisen seurauksena syntyvä hiukkasmassa. Näitä todellisessa ajossa tapahtuvia muodostumisprosesseja voidaan simuloida esimerkiksi huokoisen putken laimentimella ja hapettavalla läpivirtauskammiolla. Laboratoriossa tehtävä testaus ei nykyisellään vastaa ajoneuvon todellista käyttöä. Tässä työssä tarkasteltiin huokoisen putken laimentimen toimintaa laboratoriossa tutkimalla, miten laimennusilman lämpötila, laimennussuhde ja nukleoituvan yhdisteen pitoisuus vaikuttavat sen nukleaatiohiukkasten muodostumispotentiaaliin. Laimenninta käytettiin myös PEMS-mittauksissa (Portable Emission Measurement System) ja selvitettiin, millaiset ovat tämänhetkiset päästöstandardit täyttävän traktorin päästöt todellisissa käyttötilanteissa. PEMS-mittauksissa tarkasteltiin myös laimennusparametrien vaikutusta ja verrattiin laboratoriossa testattua laimenninta ejektorilaimentimeen. Nukleaatiomoodin muodostumisen kyseisellä huokoisen putken laimentimella havaittiin olevan tarkastelluista laimennusparametreista voimakkaasti riippuvainen. PEMS-mittauksissa oli käytössä parametrit, jotka mahdollistivat nukleaatiohiukkasten syntymisen sillä ehdolla, että nukleoituvien yhdisteiden pitoisuus on riittävän suuri. Mittauksissa ei havaittu nukleaatiomoodia. Työssä tarkasteltiin erilaisissa traktorin käyttötilanteissa muodostuvia hiukkaskokojakaumia, sekä niiden muuttumista maantieajossa ja työsuoritteissa. Työssä laskettiin traktorille hiukkaslukumäärä-, massa- ja NOx-päästökertoimia ja havaittiin niiden täyttävän nykyiset päästörajoitukset tässä työssä käytetyllä laskentamenetelmällä. Vuonna 2019 voimaan tuleva hiukkaslukumäärärajoitus ylittyi

Characterization of physical and chemical properties of particulate emissions of a modern diesel-powered tractor with PEMS-measurements

Dieselkäyttöisten ajoneuvojen päästöistä aiheutuu vuosittain merkittävä määrä kuolemia, terveysongelmia ja rahallisia tappioita. Päästölainsäädäntöä ja ajoneuvojen tyyppihyväksyntätestausta tiukennetaan jatkuvasti. Testeissä jätetään kuitenkin huomiotta alle 23 nm kiinteät hiukkaset, kaasumaisista päästöistä pakokaasun laimentuessa muodostuvat hiukkaset ja ilmakehässä tapahtuvan hapettumisen seurauksena syntyvä hiukkasmassa. Näitä todellisessa ajossa tapahtuvia muodostumisprosesseja voidaan simuloida esimerkiksi huokoisen putken laimentimella ja hapettavalla läpivirtauskammiolla. Laboratoriossa tehtävä testaus ei nykyisellään vastaa ajoneuvon todellista käyttöä. Tässä työssä tarkasteltiin huokoisen putken laimentimen toimintaa laboratoriossa tutkimalla, miten laimennusilman lämpötila, laimennussuhde ja nukleoituvan yhdisteen pitoisuus vaikuttavat sen nukleaatiohiukkasten muodostumispotentiaaliin. Laimenninta käytettiin myös PEMS-mittauksissa (Portable Emission Measurement System) ja selvitettiin, millaiset ovat tämänhetkiset päästöstandardit täyttävän traktorin päästöt todellisissa käyttötilanteissa. PEMS-mittauksissa tarkasteltiin myös laimennusparametrien vaikutusta ja verrattiin laboratoriossa testattua laimenninta ejektorilaimentimeen. Nukleaatiomoodin muodostumisen kyseisellä huokoisen putken laimentimella havaittiin olevan tarkastelluista laimennusparametreista voimakkaasti riippuvainen. PEMS-mittauksissa oli käytössä parametrit, jotka mahdollistivat nukleaatiohiukkasten syntymisen sillä ehdolla, että nukleoituvien yhdisteiden pitoisuus on riittävän suuri. Mittauksissa ei havaittu nukleaatiomoodia. Työssä tarkasteltiin erilaisissa traktorin käyttötilanteissa muodostuvia hiukkaskokojakaumia, sekä niiden muuttumista maantieajossa ja työsuoritteissa. Työssä laskettiin traktorille hiukkaslukumäärä-, massa- ja NOx-päästökertoimia ja havaittiin niiden täyttävän nykyiset päästörajoitukset tässä työssä käytetyllä laskentamenetelmällä. Vuonna 2019 voimaan tuleva hiukkaslukumäärärajoitus ylittyi