Aerosol and Air Quality Research最新文献

{"title":"Laboratory and Field Evaluations of the GeoAir2 Air Quality Monitor for Use in Indoor Environments.","authors":"Dillon Streuber,&nbsp;Yoo Min Park,&nbsp;Sinan Sousan","doi":"10.4209/aaqr.220119","DOIUrl":"https://doi.org/10.4209/aaqr.220119","url":null,"abstract":"<p><p>Low-cost aerosol sensors open routes to exposure assessment and air monitoring in various indoor and outdoor environments. This study evaluated the accuracy of GeoAir2--a recently developed low-cost particulate matter (PM) monitor--using two types of aerosols (salt and dust), and the effect of changes in relative humidity on its measurements in laboratory settings. For the accuracy experiments, 32 units of GeoAir2 were used, and for the humidity experiments, 3 units of GeoAir2 were used, alongside the OPC-N3 low-cost sensor and MiniWRAS reference instrument. The normal distribution of slopes between the salt and dust aerosols was compared for the accuracy experiments. In addition, the performance of GeoAir2 in indoor environments was evaluated compared to the pDR-1500 reference instrument by collocating GeoAir2 and pDR-1500 at three different homes for five days. For salt and dust aerosols smaller than 2.5 μm (PM_2.5), both GeoAir2 (r = 0.96-0.99) and OPC-N3 (r = 0.98-0.99) were highly correlated with the MiniWRAS reference instrument. However, GeoAir2 was less influenced by changes in humidity than OPC-N3. While GeoAir2 reported an increase in mass concentrations ranging from 100% to 137% for low and high concentrations, an increase between 181% and 425% was observed for OPC-N3. The normal distribution of the slopes for the salt aerosols was narrower than dust aerosol, which shows closer slope similarities for salt aerosols. This study also found that GeoAir2 was highly correlated with the pDR-1500 reference instrument in indoor environments (r = 0.80-0.99). These results demonstrate potential for GeoAir2 for indoor air monitoring and exposure assessments.</p>","PeriodicalId":7402,"journal":{"name":"Aerosol and Air Quality Research","volume":"22 8","pages":""},"PeriodicalIF":4.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9979595/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9450114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Three Years of High Time-resolution Air Pollution Monitoring in the Complex Multi-source Harbor of New York and New Jersey.","authors":"Gayle Hagler,&nbsp;Dan Birkett,&nbsp;Ronald C Henry,&nbsp;Richard E Peltier","doi":"10.4209/aaqr.2020.02.0069","DOIUrl":"https://doi.org/10.4209/aaqr.2020.02.0069","url":null,"abstract":"<p><p>In densely developed port areas with numerous emissions sources, relating measured air quality changes to emissions is challenging given the geographic density of sources without unique pollutant composition signatures. To better understand air quality during increasing emission controls at the Port of New York and New Jersey (\"Port\"), an air monitoring station was sited to minimize collinearity of sources along ordinal directions. The study area includes an international airport, interstate highway, port terminals and shipping lanes, and industrial sources, as well as typical urban emissions of a megacity. Because air flow travel time from sources to the monitor were usually much less than one hour, minute-by-minute, high-precision data were collected for three years (2013-2015) for sulfur dioxide (SO₂), carbon monoxide (CO), oxides of nitrogen (NO, NO₂), black carbon (BC), fine particulate matter (PM_2.5), and meteorology (wind speed, wind direction, temperature, humidity). From summer 2014 to spring 2015, hourly metals data were also collected. A high degree of temporal variability was observed for pollutants associated with direct emissions, with highest hourly average coefficient of variation observed for NO (2.65), SO₂ (1.45) and BC (1.21). Nonparametric trajectory analysis (NTA) was utilized to separate the source areas influencing the monitoring data and observe how they changed over time, with over 1.6 million trajectories computed in total. Comparing the last 5 quarters of the study to the first 5 quarters, concentrations at the monitoring site associated with three port-related geographic areas decreased by 34-41%, 11-17%, and 28-41% for SO₂, NO_x, and BC, respectively. Over the same period, indicators of shipping and cargo activity at the port remained relatively constant; therefore, a shift in emission factors is likely the cause of the change. This study demonstrates the value of high-time resolution, accurate monitoring data along with careful siting to understand source area influences.</p>","PeriodicalId":7402,"journal":{"name":"Aerosol and Air Quality Research","volume":"20 ","pages":""},"PeriodicalIF":4.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7903559/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25405624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the Morphology and Composition of Particulate Matter in an Urban Environment.","authors":"Bahadar Zeb, Khan Alam, Armin Sorooshian, Thomas Blaschke, Ifthikhar Ahmad, Imran Shahid","doi":"10.4209/aaqr.2017.09.0340","DOIUrl":"10.4209/aaqr.2017.09.0340","url":null,"abstract":"<p><p>Particulate matter (PM) plays a vital role in altering air quality, human health, and climate change. There are sparse data relevant to PM characteristics in urban environments of the Middle East, including Peshawar city in Pakistan. This work reports on the morphology and composition of PM in two size fractions (PM_2.5 and PM₁₀) during November 2016 in Peshawar. The 24 hous mass concentration of PM_2.5 varied from 72 μg m^-3 to 500 μg m^-3 with an average value of 286 μg m^-3. The 24 hours PM₁₀ concentration varied from 300 μg m^-3 to 1440 μg m^-3 with an average of 638 μg m^-3. The morphology, size, and elemental composition of PM were measured using Fourier Transform Infra Red (FT-IR) Spectroscopy and Scanning Electron Microscopy (SEM) with Energy Dispersive X-ray (EDX) Spectroscopy. The size of the analyzed particles by EDX ranged from 916 nm to 22 μm. Particles were classified into the following groups based on their elemental composition and morphology: silica (12%), aluminosilicates (23%), calcium rich (3%), chloride (2%), Fe/Ti oxides (3%), carbonaceous (49%), sulfate (5%), biogenic (3%). The major identified sources of PM are vehicular emissions, biomass burning, soil and re-suspended road dust, biological emissions, and construction activities in and around the vicinity of the sampling site.</p>","PeriodicalId":7402,"journal":{"name":"Aerosol and Air Quality Research","volume":"18 6","pages":"1431-1447"},"PeriodicalIF":4.0,"publicationDate":"2018-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6192059/pdf/nihms960049.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"36604931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of PM_2.5 Exposure in Hazy and Non-Hazy Days in Nanjing, China.","authors":"Ting Zhang,&nbsp;Steven N Chillrud,&nbsp;Junfeng Ji,&nbsp;Yang Chen,&nbsp;Masha Pitiranggon,&nbsp;Wenqing Li,&nbsp;Zhenyang Liu,&nbsp;Beizhan Yan","doi":"10.4209/aaqr.2016.07.0301","DOIUrl":"10.4209/aaqr.2016.07.0301","url":null,"abstract":"<p><p>Fine particulate matter (PM_2.5), levels of which are about 6 times the 2014 WHO air quality guidelines for 190 cities in China, has been found to be associated with various adverse health outcomes. In this study, personal PM_2.5 exposures were monitored along a fixed routine that included 19 types of non-residential micro-environments (MEs) on 4 hazy days (ambient PM_2.5 292 ± 70 μg m^-3) and 2 non-hazy days (55 ± 16 μg m^-3) in Nanjing, China using miniaturized real-time portable particulate sensors that also collect integrated filters of PM_2.5 (MicroPEMs, Research Triangle Institute (RTI), NC). Gravimetric correction is necessary for nephelometer devices in calculating real-time PM levels. During both hazy and non-hazy days, personal PM_2.5 levels were generally higher in MEs with noticeable PM_2.5 sources than MEs serving as receptor sites, higher in open MEs than indoor MEs, and higher in densely populated MEs than MEs with few people. Personal PM_2.5 levels measured during hazy and non-hazy days were 242 ± 91 μg m^-3 and 103 ± 147 μg m^-3, respectively. The ratio of personal exposure to ambient PM_2.5 levels (<i>r_p/a</i> ) was less than 1.0 and less variable on hazy days (0.85 ± 0.31); while it was larger than 1.0 and more variable on non-hazy days (1.71 ± 1.93), confirming the importance of local sources other than ambient during non-hazy days. Air handling methods (e.g., ventilation/filtration) impacted personal exposures in enclosed locations on both types of days. Street food vendors with cooking emissions were MEs with the highest personal PM_2.5 levels while subway cars in Nanjing were relatively clean due to good air filtration on both hazy and non-hazy days. In summary, on hazy days, personal exposure was mainly affected by the regional ambient levels, while on non-hazy days, local sources together with ambient levels determined personal exposure levels.</p>","PeriodicalId":7402,"journal":{"name":"Aerosol and Air Quality Research","volume":"17 9","pages":"2235-2246"},"PeriodicalIF":4.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6301043/pdf/nihms979284.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"36811624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of PM_2.5 surface concentration simulated by Version 1 of the NASA's MERRA Aerosol Reanalysis over Israel and Taiwan.","authors":"Simon Provençal, Virginie Buchard, Arlindo M da Silva, Richard Leduc, Nathalie Barrette, Emily Elhacham, Sheng-Hsiang Wang","doi":"10.4209/aaqr.2016.04.0145","DOIUrl":"10.4209/aaqr.2016.04.0145","url":null,"abstract":"<p><p>Version 1 of the NASA MERRA Aerosol Reanalysis (MERRAero) assimilates bias-corrected aerosol optical depth (AOD) data from MODIS-Terra and MODIS-Aqua, and simulates particulate matter (PM) concentration data to reproduce a consistent database of AOD and PM concentration around the world from 2002 to the end of 2015. The purpose of this paper is to evaluate MERRAero's simulation of fine PM concentration against surface measurements in two regions of the world with relatively high levels of PM concentration but with profoundly different PM composition, those of Israel and Taiwan. Being surrounded by major deserts, Israel's PM load is characterized by a significant contribution of mineral dust, and secondary contributions of sea salt particles, given its proximity to the Mediterranean Sea, and sulfate particles originating from Israel's own urban activities and transported from Europe. Taiwan's PM load is composed primarily of anthropogenic particles (sulfate, nitrate and carbonaceous particles) locally produced or transported from China, with an additional contribution of springtime transport of mineral dust originating from Chinese and Mongolian deserts. The evaluation in Israel produced favorable results with MERRAero slightly overestimating measurements by 6% on average and reproducing an excellent year-to-year and seasonal fluctuation. The evaluation in Taiwan was less favorable with MERRAero underestimating measurements by 42% on average. Two likely reasons explain this discrepancy: emissions of anthropogenic PM and their precursors are largely uncertain in China, and MERRAero doesn't include nitrate particles in its simulation, a pollutant of predominately anthropogenic sources. MERRAero nevertheless simulates well the concentration of fine PM during the summer, when Taiwan is least affected by the advection of pollution from China.</p>","PeriodicalId":7402,"journal":{"name":"Aerosol and Air Quality Research","volume":"17 1","pages":"253-261"},"PeriodicalIF":4.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5901751/pdf/nihms954315.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"36022717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatial Variation of Ground Level Ozone Concentrations and its Health Impacts in an Urban Area in India.","authors":"Amit Kumar Gorai,&nbsp;Paul B Tchounwou,&nbsp;Gargi Mitra","doi":"10.4209/aaqr.2016.08.0374","DOIUrl":"https://doi.org/10.4209/aaqr.2016.08.0374","url":null,"abstract":"<p><p>The present study was designed to analyze the spatial distributions of ground-level ozone (GLO) concentrations in Ranchi (Jharkhand, India) using geostatistical approaches. From September 2014 to August 2015, monthly GLO concentrations were monitored in 40-identified locations distributed in the region of study. In every month, the monitoring was done at three different time periods of the day; 5.30 AM to 7.30 AM, 11.30 AM to 1.30 PM, and 5.30 PM to 8 PM). The time duration was assigned based on the temporal variations of GLO concentrations. The descriptive statistics indicate that the spatial mean ozone concentrations ranged from 23.45 μg m^-3 to 53.91 μg m^-3 in morning hours, from 82.50 μg m^-3 to 126.66 μg m^-3 in the day time and from 40.04 μg m^-3 to 71.25 μg m^-3 in the evening hours. The higher level of spatial variance observed in the months of December (standard deviation: 24.21), July (standard deviation: 29.59) and November (standard deviation: 19.60) for the morning, noon, and evening time, respectively. The effects of meteorological factors (wind speed and wind direction) on the ozone concentrations were also analysed. The study confirmed that wind speed is not the dominant factor for influencing the GLO concentrations. The study also analysed the ozone air quality index (OZAQI) for assessing the health impacts in the study area. The result suggests that most of the area had the moderate category of OZAQI (101-200) and that leads to breathing discomfort for people with lung and heart disease.</p>","PeriodicalId":7402,"journal":{"name":"Aerosol and Air Quality Research","volume":"17 4","pages":"951-964"},"PeriodicalIF":4.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4209/aaqr.2016.08.0374","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"35511008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurement of Soluble and Total Hexavalent Chromium in the Ambient Airborne Particles in New Jersey.","authors":"Lihui Huang,&nbsp;Chang Ho Yu,&nbsp;Philip K Hopke,&nbsp;Paul J Lioy,&nbsp;Brian T Buckley,&nbsp;Jin Young Shin,&nbsp;Zhihua Tina Fan","doi":"10.4209/aaqr.2013.10.0312","DOIUrl":"https://doi.org/10.4209/aaqr.2013.10.0312","url":null,"abstract":"<p><p>Hexavalent chromium (Cr(VI)) in ambient airborne particulate matter (PM) is a known pulmonary carcinogen and may have both soluble and insoluble forms. The sum of the two forms is defined as total Cr(VI). Currently, there were no methods suitable for large-scale monitoring of total Cr(VI) in ambient PM. This study developed a method to measure total Cr(VI) in ambient PM. This method includes PM collection using a Teflon filter, microwave extraction with 3% Na₂CO₃-2% NaOH at 95°C for 60 minutes, and Cr(VI) analysis by 1,5-diphenylcarbazide colorimetry at 540 nm. The recoveries of total Cr(VI) were 119.5 ± 10.4% and 106.3 ± 16.7% for the Cr(VI)-certified reference materials, SQC 012 and SRM 2700, respectively. Total Cr(VI) in the reference urban PM (NIST 1648a) was 26.0 ± 3.1 mg/kg (%CV = 11.9%) determined by this method. The method detection limit was 0.33 ng/m³. This method and the one previously developed to measure ambient Cr(VI), which is soluble in pH ~9.0 aqueous solution, were applied to measure Cr(VI) in ambient PM₁₀ collected from three urban areas and one suburban area in New Jersey. The total Cr(VI) concentrations were 1.05-1.41 ng/m³ in the winter and 0.99-1.56 ng/m³ in the summer. The soluble Cr(VI) concentrations were 0.03-0.19 ng/m³ in the winter and 0.12-0.37 ng/m³ in the summer. The summer mean ratios of soluble to total Cr(VI) were 14.3-43.7%, significantly higher than 4.2-14.4% in the winter. The winter concentrations of soluble and total Cr(VI) in the suburban area were significantly lower than in the three urban areas. The results suggested that formation of Cr(VI) via atmospheric chemistry may contribute to the higher soluble Cr(VI) concentrations in the summer.</p>","PeriodicalId":7402,"journal":{"name":"Aerosol and Air Quality Research","volume":"14 7","pages":"1939-1949"},"PeriodicalIF":4.0,"publicationDate":"2014-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4480920/pdf/nihms653790.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"33428381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Validation of MicroAeth® as a Black Carbon Monitor for Fixed-Site Measurement and Optimization for Personal Exposure Characterization.","authors":"Jing Cai,&nbsp;Beizhan Yan,&nbsp;James Ross,&nbsp;Danian Zhang,&nbsp;Patrick L Kinney,&nbsp;Matthew S Perzanowski,&nbsp;KyungHwa Jung,&nbsp;Rachel Miller,&nbsp;Steven N Chillrud","doi":"10.4209/aaqr.2013.03.0088","DOIUrl":"https://doi.org/10.4209/aaqr.2013.03.0088","url":null,"abstract":"<p><p>This paper reports on validation experiments with the recently developed microAeth®, a pocket-sized device which is able to obtain real-time and personal measurements of black carbon (BC) aerosol. High reproducibility was observed when comparing the results from six new individual units during fixed-site monitoring out of a window (relative standard deviation [RSD] = 8% ± 5%, N = 1442). The results obtained from the microAeth devices agreed with those obtained from a full size rack mounted Aethalometer, based on both the 1-minute data (R = 0.92, slope = 1.01 ± 0.01, N = 1380) and 24-h average data. The 24-h average of real time data obtained from the microAeths was comparable to the BC concentration obtained from 24-h integrated PM_2.5 filter deposits, as determined by multi-wavelength optical absorption (R = 0.98, slope = 0.92 ± 0.07, N = 12). Rapid environmental changes in relative humidity (RH) and temperature (T) can result in false positive and negative peaks in the real time BC concentrations, though averages > 1-2-hour are only minimally affected. An inlet with a diffusion drier based on Nafion® tubing was developed in order to use BC data with a high time resolution. The data shows that the diffusion drier greatly reduce the impacts from rapid changes in RH and T when the monitoring system is worn in close proximity to the body (e.g., in the vest pocket).</p>","PeriodicalId":7402,"journal":{"name":"Aerosol and Air Quality Research","volume":"14 1","pages":"1-9"},"PeriodicalIF":4.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4209/aaqr.2013.03.0088","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"32832824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correction factor for continuous monitoring of wood smoke fine particulate matter.","authors":"Marcy L McNamara,&nbsp;Curtis W Noonan,&nbsp;Tony J Ward","doi":"10.4209/aaqr.2010.08.0072","DOIUrl":"https://doi.org/10.4209/aaqr.2010.08.0072","url":null,"abstract":"<p><p>The US Environmental Protection Agency (EPA) has designated a handful of instruments as Federal Reference or Federal Equivalency Methods (FRM and FEM, respectively) for the monitoring of fine particulate matter (PM_2.5). More commonly used for indoor exposure assessment studies are optical scanning devices such as the DustTrak (TSI) due to the their portability and affordability. It is recommended by the manufacturer of these instruments that a \"correction factor\" be applied when assessing source-specific conditions. In this study, DustTraks were collocated with multiple samplers in various environments in an effort to establish an indoor, wood smoke-source specific correction factor. The DustTrak was found to report PM_2.5 levels on average 1.6 times higher than a filter based method in two indoor sampling programs. The DustTrak also reported indoor PM_2.5 concentrations 1.7 times higher than a FRM sampler during a regional forest fire event. These real-world scenarios give a correction factor within a reasonable range of the results of a controlled laboratory experiment in which DustTraks reported PM_2.5 approximately 2 times higher than a FEM. Our indoor wood smoke-specific correction factor of 1.65 will allow for DustTraks to be confidently used in quantifying PM_2.5 exposures within indoor environments predominantly impacted by wood smoke.</p>","PeriodicalId":7402,"journal":{"name":"Aerosol and Air Quality Research","volume":"11 3","pages":"315-322"},"PeriodicalIF":4.0,"publicationDate":"2011-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4214921/pdf/nihms344195.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"32788541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}