scholarly journals Identification of decadal trends and associated causes for organic and elemental carbon in PM2.5 at Canadian urban sites

2022 ◽  
Vol 159 ◽  
pp. 107031
Author(s):  
Huanbo Wang ◽  
Leiming Zhang ◽  
Xiaohong Yao ◽  
Irene Cheng ◽  
Ewa Dabek-Zlotorzynska
Keyword(s):  
Elemental Carbon ◽  
Urban Sites

Organic and elemental carbon associated to PM10 and PM2.5 at urban sites of northern Greece

2013 ◽  
Vol 21 (3) ◽  
pp. 1769-1785 ◽  
Author(s):  
Constantini Samara ◽  
Dimitra Voutsa ◽  
Athanasios Kouras ◽  
Kostas Eleftheriadis ◽  
Thomas Maggos ◽  
...  
Keyword(s):  
Elemental Carbon ◽  
Northern Greece ◽  
Pm10 And Pm2.5 ◽  
Urban Sites

Elemental carbon deposition to Svalbard snow from Norwegian settlements and long-range transport

Tellus B ◽  
2011 ◽  
Vol 63 (3) ◽  
Author(s):  
Borgar Aamaas ◽  
Carl Egede Bøggild ◽  
Frode Stordal ◽  
Terje Berntsen ◽  
Kim Holmén ◽  
...  
Keyword(s):  
Long Range ◽  
Elemental Carbon ◽  
Carbon Deposition ◽  
Long Range Transport ◽  
Range Transport

EXPRESS: Laser-Induced Breakdown Spectroscopy (LIBS) Combined with Temporal Plasma Analysis of C2 Molecular Emission for Carbon Analysis in Coal

2021 ◽  
pp. 000370282110123
Author(s):  
Hemalaxmi Rajavelu ◽  
Nilesh J Vasa ◽  
Satyanarayanan Seshadri
Keyword(s):  
Elemental Carbon ◽  
Partial Least Square ◽  
Laser Induced Breakdown Spectroscopy ◽  
Nanosecond Laser ◽  
Calibration Model ◽  
Breakdown Spectroscopy ◽  
Persistence Time ◽  
Relative Standard ◽  
Laser Induced Breakdown ◽  
Spectral Intensities

A benchtop Laser-Induced Breakdown Spectroscopy (LIBS) is demonstrated to determine the elemental carbon content present in raw coal used for combustion in power plants. The spectral intensities of molecular CN and C2 emission are measured together with the atomic carbon (C) and other inorganic elements (Si, Fe, Mg, Al, Ca, Na, and K) in the LIBS spectrum of coal. The emission persistence time of C2 molecule emission is measured from the coal plasma generated by a nanosecond laser ablation with a wavelength of 266 nm in the Ar atmosphere. The emission persistence time of molecular C2 emission along with the spectral intensities of major ash elements (Fe, Si, Al, and Ca) and carbon emissions (atomic C, molecular CN, and C2) shows a better relationship with the carbon wt% of different coal samples. The calibration model to measure elemental carbon (wt%) is developed by combining the spectral characteristics (Spectral intensity) and the temporal characteristics (Emission persistence time of C2 molecule emission). The temporal characteristic studies combined with the spectroscopic data in the PLSR (Partial Least Square Regression) model has resulted in an improvement in the root mean square error of validation (RMSEV), and the relative standard deviation (RSD) is reduced from 10.86% to 4.12% and from 11.32% to 6.04%, respectively.

scholarly journals EPID-07. ACCESS TO GLIOBLASTOMA CLINICAL TRIALS FOR RURAL PATIENTS IN THE UNITED STATES FROM 2010–2020

2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii79-ii79
Author(s):  
Kathryn Nevel ◽  
Samuel Capouch ◽  
Lisa Arnold ◽  
Katherine Peters ◽  
Nimish Mohile ◽  
...  
Keyword(s):  
United States ◽  
Clinical Trials ◽  
Rural Communities ◽  
The United States ◽  
Interventional Treatment ◽  
Phase Ii Trials ◽  
Treatment Trials ◽  
Rural Sites ◽  
Rural Patients ◽  
Urban Sites

Abstract BACKGROUND Patients in rural communities have less access to optimal cancer care and clinical trials. For GBM, access to experimental therapies, and consideration of a clinical trial is embedded in national guidelines. Still, the availability of clinical trials to rural communities, representing 20% of the US population, has not been described. METHODS We queried ClinicalTrials.gov for glioblastoma interventional treatment trials opened between 1/2010 and 1/2020 in the United States. We created a Structured Query Language database and leveraged Google application programming interfaces (API) Places to find name and street addresses for the sites, and Google’s Geocode API to determine the county location. Counties were classified by US Department of Agriculture Rural-Urban Continuum Codes (RUCC 1–3 = urban and RUCC 4–9 = rural). We used z-ratios for rural-urban statistical comparisons. RESULTS We identified 406 interventional treatment trials for GBM at 1491 unique sites. 8.7% of unique sites were in rural settings. Rural sites opened an average of 1.7 trials/site and urban sites 2.8 trials/site from 1/2010–1/2020. Rural sites offered more phase II trials (63% vs 57%, p= 0.03) and fewer phase I trials (22% vs 28%, p= 0.01) than urban sites. Rural locations were more likely to offer federally-sponsored trials (p< 0.002). There were no investigator-initiated or single-institution trials offered at rural locations, and only 1% of industry trials were offered rurally. DISCUSSION Clinical trials for GBM were rarely open in rural areas, and were more dependent on federal funding. Clinical trials are likely difficult to access for rural patients, and this has important implications for the generalizability of research as well as how we engage the field of neuro-oncology and patient advocacy groups in improving patient access to trials. Increasing the number of clinical trials in rural locations may enable more rural patients to access and enroll in GBM studies.

Identification of Potential Freight Parking Locations in Urban Areas

2021 ◽  
pp. 036119812110130
Author(s):  
Glenn Vorhes ◽  
Ernest Perry ◽  
Soyoung Ahn
Keyword(s):  
United States ◽  
Information System ◽  
Satellite Imagery ◽  
Urban Areas ◽  
The United States ◽  
Truck Drivers ◽  
Short List ◽  
Automated Processes ◽  
Parking Facilities ◽  
Urban Sites

Truck parking is a crucial element of the United States’ transportation system as it provides truckers with safe places to rest and stage for deliveries. Demand for truck parking spaces exceeds supply and shortages are especially common in and around urban areas. Freight operations are negatively affected as truck drivers are unable to park in logistically ideal locations. Drivers may resort to unsafe practices such as parking on ramps or in abandoned lots. This report seeks to examine the potential parking availability of vacant urban parcels by establishing a methodology to identify parcels and examining whether the identified parcels are suitable for truck parking. Previous research has demonstrated that affordable, accessible parcels are available to accommodate truck parking. When used in conjunction with other policies, adaptation of urban sites could help reduce the severity of truck parking shortages. Geographic information system parcel and roadway data were obtained for one urban area in each of the 10 Mid America Association of Transportation Officials region states. Area and proximity filters were applied followed by spectral analysis of satellite imagery to identify candidate parcels for truck parking facilities within urban areas. The automated processes created a ranked short list of potential parcels from which those best suited for truck parking could be efficiently identified for inspection by satellite imagery. This process resulted in a manageable number of parcels to be evaluated further by local knowledge metrics such as availability and cost, existing infrastructure and municipal connections, and safety.

scholarly journals Spatiotemporal distribution of light-absorbing carbon and its relationship to other atmospheric pollutants in Stockholm

2011 ◽  
Vol 11 (22) ◽  
pp. 11553-11567 ◽  
Author(s):  
P. Krecl ◽  
A. C. Targino ◽  
C. Johansson
Keyword(s):  
Exhaust Emissions ◽  
Atmospheric Pollutants ◽  
Spatiotemporal Variability ◽  
Rural Site ◽  
Strong Increase ◽  
Population Exposure ◽  
Emission Sources ◽  
Vehicle Exhaust ◽  
Urban Background ◽  
Urban Sites

Abstract. Carbon-containing particles have deleterious effects on both Earth's climate and human health. In Europe, the main sources of light-absorbing carbon (LAC) emissions are the transport (67%) and residential (25%) sectors. Information on the spatiotemporal variability of LAC particles in urban areas is relevant for air quality management and to better diagnose the population exposure to these particles. This study reports on results of an intensive field campaign conducted at four sites (two kerbside stations, one urban background site and a rural station) in Stockholm, Sweden, during the spring 2006. Light-absorbing carbon mass (MLAC) concentrations were measured with custom-built Particle Soot Absorption Photometers (PSAP). The spatiotemporal variability of MLAC concentrations was explored by examining correlation coefficients (R), coefficients of divergence (COD), and diurnal patterns at all sites. Simultaneous measurements of NOx, PM10, PM2.5, and meteorological variables were also carried out at the same locations to help characterize the LAC emission sources. Hourly mean (± standard deviation) MLAC concentrations ranged from 0.36±0.50 at the rural site to 5.39±3.60 μg m−3 at the street canyon site. Concentrations of LAC between urban sites were poorly correlated even for daily averages (R<0.70), combined with highly heterogeneously distributed concentrations (COD>0.30) even at spatial scales of few kilometers. This high variability is connected to the distribution of emission sources and processes contributing to the LAC fraction at these sites. At urban sites, MLAC tracked NOx levels and traffic density well and mean MLAC/PM2.5 ratios were larger (26–38%) than at the background sites (4–10%). The results suggest that vehicle exhaust emissions are the main responsible for the high MLAC concentrations found at the urban locations whereas long-range transport (LRT) episodes of combustion-derived particles can generate a strong increase of levels at background sites. To decrease pollution levels at kerbside and urban background locations in Stockholm, we recommend abatement strategies that target reductions of vehicle exhaust emissions, which are the main contributors to MLAC and NOx concentrations.

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