scholarly journals FTIR Measurements of Greenhouse Gases over Thessaloniki, Greece in the Framework of COCCON and Comparison with S5P/TROPOMI Observations

2021 ◽  
Vol 13 (17) ◽  
pp. 3395
Author(s):  
Marios Mermigkas ◽  
Chrysanthi Topaloglou ◽  
Dimitrios Balis ◽  
Maria Elissavet Koukouli ◽  
Frank Hase ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Fossil Fuels ◽  
Late Summer ◽  
Mean Value ◽  
Anthropogenic Sources ◽  
Mean Values ◽  
Local Sources ◽  
Summer Minimum ◽  
The Impact ◽  
First Time

In this work, column-averaged dry-air mole fractions of carbon dioxide (XCO2), methane (XCH4) and carbon monoxide (XCO) are presented for the first time at a mid-latitude urban station, Thessaloniki, Greece, using the Bruker EM27/SUN ground-based low-resolution Fourier Transform spectrometer operated according to the requirements of the Collaborative Carbon Column Observing Network (COCCON). Two years of measurements are presented and examined for seasonal variability. The observed XCO2 levels show the expected seasonal cycle (spring maximum, late summer minimum) with a peak-to-peak amplitude of 12 ppm, with maximum values reported for winter 2021 exceeding 416 ppm. The XCH4 values are shown to increase in the second half of the year, with autumn showing the highest mean value of 1.878 ± 0.01 ppm. The XCO levels, following anthropogenic sources, show high winter and low summer values, exhibiting a rise again in August and September with a maximum value of 114 ± 3 ppb and a minimum in summer 2020 of 76 ± 3 ppb. Additionally, methane and carbon monoxide products obtained from the TROPOspheric Monitoring Instrument (TROPOMI), Sentinel-5P space borne sensor, are compared with the ground-based measurements. We report a good agreement between products. The relative mean bias for methane and carbon monoxide are −0.073 ± 0.647% and 3.064 ± 5.566%, respectively. Furthermore, a 15-day running average is subtracted from the original daily mean values to provide ΔXCO2, ΔXCO and ΔXCH4 residuals, so as to identify local sources at a synoptic scale. ΔXCO and ΔXCO2 show the best correlation in the winter (R2 = 0.898, slope = 0.007) season due to anthropogenic emissions in this period of the year (combustion of fossil fuels or industrial activities), while in summer no correlation is found. ΔXCO and ΔXCH4 variations are similar through both years of measurements and have a very good correlation in all seasons including winter (R2 = 0.804, slope = 1.209). The investigation of the X-gases comparison is of primary importance in order to identify local sources and quantify the impact of these trace gases to the deregulation of earth-climate system balance.

Comparison of Emission Levels of Motor Cars, Motorcycles, and Tricycles Using Petrol Engines in Southwestern Nigeria

2021 ◽  
Vol 900 ◽  
pp. 183-187
Author(s):  
Odunlami Olayemi Abosede ◽  
Akeredolu Funso Alaba
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Carbon Dioxide Emissions ◽  
Mean Value ◽  
Southwestern Nigeria ◽  
Mean Values ◽  
Mobile Sources ◽  
Southwest Nigeria ◽  
The Mean ◽  
European Standards

The emissions of carbon monoxide, carbon dioxide, and hydrocarbon from four stroke-powered motorcars and two stroke-powered motorcycles and tricycles in Southwest Nigeria were examined using an automotive 4-gas analyer. Results show that tricycles produced more hydrocarbon and carbon monoxide emissions than motorcycles, while motorcycles emitted more of these pollutants than the gasoline fueled motor cars. (The gasoline fueled motorcars produced lowest hydrocarbon and carbon monoxide while the tricycles produced the highest hydrocarbon and carbon monoxide emissions). On the contrary, motor cars had the highest mean value of carbon dioxide followed by the motorcycles, while tricycles had the least. This could be attributed to the presence of the catalytic converters in some of the motor cars oxidizing carbon monoxide to carbon dioxide. The mean values of hydrocarbon, carbon monoxide and carbon dioxide emissions from motorcars are 630ppm, 10200ppm and 59900ppm. This is much higher than the NESREA (National Environmental standards and Regulations Enforcement Agency) standards as well as Euro II and Euro III (European standards) for vehicular emission. The mean values for hydrocarbon, carbon monoxide and carbon dioxide emissions from motorcycles and tricycles are (2150ppm, 21530ppm and 31200ppm) and (2820ppm, 24880ppm and 38710ppm) respectively. These results do not comply with Nigeria and European emission standards for hydrocarbon, and carbon monoxide. Tricycles and motorcycles account for higher concentrations of hydrocarbon and carbon monoxide pollutants from mobile sources, while they emit carbon dioxide minimally.

​Impact of Extreme Hot Environmental Temperature Period on Marker Enzymes of Carbohydrate Metabolism in Non-descript Sheep from Arid Tracts of Rajasthan

2021 ◽  
Author(s):  
Anandita Srivastava ◽  
Nalini Kataria
Keyword(s):  
Carbohydrate Metabolism ◽  
Environmental Temperature ◽  
Age Groups ◽  
Extreme Temperature ◽  
Mean Value ◽  
Marker Enzymes ◽  
Mean Values ◽  
The Mean ◽  
The Impact ◽  
Enzymes Of Carbohydrate Metabolism

Background: The present investigation was envisaged to find out the impact of extreme hot environmental temperature period (ETP) on marker enzymes of carbohydrate metabolism in male and female non-descript sheep of various age groups i.e. 4 to 13 months from arid tracts of Rajasthan. Glucose-6-phosphate dehydrogenase (G-6-PDH) and malate dehydrogenase (MDH) marker enzymes of carbohydrate metabolism were considered for study. Methods: During the period October 2016-June 2017 blood samples were collected to harvest sera for spectrophotometric method from 240 healthy animals selected from private slaughter house during moderate and extreme hot environmental temperature periods (ETPs). The mean values of markers attained during moderate ETP were reckoned as the control. It was 10.00 ± 0.10 UL-1 and 42.00±1.00 respectively. Conclusion: The mean value of MDH was significantly (p≤0.05) higher while G-6-PDH significantly (p≤0.05) lowers during extreme hot temperature in comparison to moderate period. Therefore, it could be concluded that variations in enzyme markers were associated with changes in environmental temperatures. Probably ETP were able to produce a profound effect on carbohydrate metabolism in sheep. Therfore it can be suggested that during the period of extreme temperature balanced ration must be provided to the animal along with proper management to decrease the severity of temperature impact.

scholarly journals Impact of Two Remineralizing Agents on White Spot Lesions

2020 ◽  
Author(s):  
Ebaa Ibrahim Alagha
Keyword(s):  
Mean Value ◽  
White Spot ◽  
Control Group ◽  
Main Concern ◽  
White Spot Lesions ◽  
Mean Values ◽  
Restorative Treatment ◽  
Significant Difference ◽  
Group B ◽  
The Impact

Abstract Aim of the study: This study evaluated the impact of two remineralizing agents containing casein phosphopeptideamorphous calcium phosphate (CPPACP), and Tricalcium phosphate (TCP) on white spot lesions. Materials and Methods: A total of ninety freshly extracted upper premolars were divided in three equal groups (30 each). Group A: Control group. Group B: Varnish containing CPP–ACP. Group C: Varnish containing TCP. The teeth were subjected to Diagnodent test after inducing white spot lesions to assess any surface changes present on the teeth. The readings were repeated post demineralization and post-remineralization. Results: Statistically significant difference was present in the mean values between the tested groups. CPP-ACP group recorded higher mean value at demineralization when compared to TCP group. Statistically significant difference (p < 0.0001) was present between the baseline and the demineralization values. CPP-ACP group presented higher remineralization results when compared to TCP group. T-test proved a significant difference between the tested groups. Conclusion: CPP-ACP containing varnish had higher remineralizing effect when compared to TCP containing varnish. Clinical Significance: Recently, the focus of restorative dentistry has been directed toward a conservative approach. Prevention and non-restorative treatment of initial enamel caries is the main concern. Remineralization procedures are the most preferred way of regeneration of lost tooth structure.

scholarly journals Colonization Patterns, Phenology and Seasonal Abundance of the Nearctic Leafhopper Erasmoneura vulnerata (Fitch), a New Pest in European Vineyards

Insects ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 731
Author(s):  
Carlo Duso ◽  
Giulia Zanettin ◽  
Pamela Gherardo ◽  
Giulia Pasqualotto ◽  
Damiano Raniero ◽  
...  
Keyword(s):  
Late Summer ◽  
Seasonal Abundance ◽  
Growing Seasons ◽  
Rural Buildings ◽  
North Eastern ◽  
Colonization Patterns ◽  
A Minor ◽  
The Impact ◽  
First Time ◽  
Leaf Symptoms

The Nearctic leafhopper Erasmoneura vulnerata (Fitch), detected in Europe for the first time (north-eastern Italy) in 2004, has remained a minor pest of grapevine for more than 10 years. The first outbreaks of E. vulnerata were reported in 2016 in commercial vineyards located in north-eastern Italy. High population densities and severe leaf symptoms (i.e., leaf discoloration and fall) were observed in late summer despite the application of insecticides. Investigations were carried out from 2017 to 2019 in 10 vineyards located in Veneto region (Vicenza and Verona provinces) to shed light on the seasonal abundance of E. vulnerata on different Vitis vinifera cultivars. Pest phenology was studied in six vineyards where the impact of insecticides was minimal. Erasmoneura vulnerata completed three generations in each of the growing seasons. Vineyard colonization by overwintered adults showed a clear edge effect, suggesting the influence of overwintering sites (e.g., rural buildings and hedgerows) in vineyard margins. The impact of natural enemies on pest populations appeared to be limited and mostly related to egg parasitoids. Organic vineyards were more heavily infested by E. vulnerata compared to conventional vineyards, likely due to the minimal efficacy of natural insecticides typically used in the former farms.

scholarly journals CO2 Hydrogenation to Methanol over Ce and Zr Containing UiO-66 and Cu/UiO-66

Catalysts ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 39 ◽  
Author(s):  
Michalina Stawowy ◽  
Radosław Ciesielski ◽  
Tomasz Maniecki ◽  
Krzysztof Matus ◽  
Rafał Łużny ◽  
...  
Keyword(s):  
Active Sites ◽  
Fossil Fuels ◽  
Co2 Hydrogenation ◽  
Structure Stability ◽  
New Class ◽  
Developed Surface ◽  
Metal Organic ◽  
Direct Hydrogenation ◽  
The Impact ◽  
First Time

Direct hydrogenation of CO2 to methanol is an interesting method to recycle CO2 emitted e.g., during combustion of fossil fuels. However, it is a challenging process because both the selectivity to methanol and its production are low. The metal-organic frameworks are relatively new class of materials with a potential to be used as catalysts or catalysts supports, also in the reaction of MeOH production. Among many interesting structures, the UiO-66 draws significant attention owing to its chemical and thermal stability, developed surface area, and the possibility of tuning its properties e.g., by exchanging the zirconium in the nodes to other metal cations. In this work we discuss—for the first time—the performance of Cu supported on UiO-66(Ce/Zr) in CO2 hydrogenation to MeOH. We show the impact of the composition of UiO-66-based catalysts, and the character of Cu-Zr and Cu-Ce interactions on MeOH production and MeOH selectivity during test carried out for 25 h at T = 200 °C and p = 1.8 MPa. Significant increase of selectivity to MeOH was noticed after exchanging half of Zr4+ cations with Ce4+; however, no change in MeOH production occurred. It was found that the Cu-Ce coexistence in the UiO-66-based catalytic system reduced the selectivity to MeOH when compared to Cu/UiO-66(Zr), which was ascribed to lower concentration of Cu0 active sites in Cu/UiO-66(Ce/Zr), and this was caused by oxygen spill-over between Cu0 and Ce4+, and thus, the oxidation of the former. The impact of reaction conditions on the structure stability of tested catalyst was also determined.

The impact of low-flow season on source drinking water quality, Rosetta branch, Egypt

2017 ◽  
Vol 7 (3) ◽  
pp. 477-484 ◽  
Author(s):  
K. Ghodeif ◽  
R. Wahaab ◽  
S. Sorour
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Water Source ◽  
Mean Value ◽  
Low Flow ◽  
Drinking Water Source ◽  
Management Options ◽  
Mean Values ◽  
The Mean ◽  
The Impact

The present work was conducted to document the problems raised regarding low-flow in the Rosetta branch, Egypt and to develop management options to protect drinking water sources. The water quality was monitored during low-flow periods at four drinking water intakes. Results showed an increase in electric conductivity (EC), ammonium (NH4), nitrite (NO2), phosphate (PO4), and total organic carbon (TOC) during the low-flow period. EC ranges from 454 to 1,062 μS/cm and the mean value is 744. Ammonium ranges from 0.38 to 18.5 mg/L and the mean value is 5.45. NO2, PO4, and TOC have mean values of 0.73, 1.85, and 6.71 mg/L, respectively. Statistical evaluation revealed the association of NH4, EC, and PO4 that are good indicators for the load of wastewater. High ammonium often refers to a bad situation regarding oxygen while high nitrite indicates the first oxidation for wastewater through microbiological processes. The low-flow action has a serious impact on drinking water source. A high content of ammonium has delayed coagulation, enhanced algae growth, and prevented the breakpoint being reached during chlorination processes. Potential management options to deal with water scarcity and low-flow, meanwhile reducing the contaminant load in the source drinking water were proposed.

scholarly journals Long-Term eBC Measurements with the Use of MAAP in the Polluted Urban Atmosphere (Poland)

Atmosphere ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 808
Author(s):  
Natalia Zioła ◽  
Barbara Błaszczak ◽  
Krzysztof Klejnowski
Keyword(s):  
Fine Particulate Matter ◽  
Pollutant Dispersion ◽  
Urban Atmosphere ◽  
Anthropogenic Sources ◽  
Urban Background ◽  
Remedial Actions ◽  
The Impact ◽  
First Time ◽  
Absorption Photometer

In recent years, black carbon (BC) has been gaining more attention due to the diversity of anthropogenic sources and the harmful effects on human health, environment, and climate. In this paper, for the first time in Poland, the results of long-term measurements of eBC concentrations (2009–2020) at the urban background station in Zabrze (southern Poland) are presented. A Multi-Angle Absorption Photometer (MAAP) was used, which enables the measurement of eBC concentration in fine particulate matter (PM2.5). The mean concentration of eBC over the 11-year period (3.82 μg·m−3) was higher compared to the values recorded at most European urban stations. Annual averaged eBC levels showed a downward trend and clear seasonal variations, which was caused mainly by changes in the intensity of anthropogenic emissions. The impact of meteorological parameters, in particular air temperature and wind speed, which determine the intensity of emissions and the conditions of pollutant dispersion, was not without significance. The work additionally attempts to assess the possible impact of remedial actions carried out in Zabrze over the last decade. The results showed that modernization in industry and heating and maintenance of green areas potentially had the most important impact on the decline in eBC concentrations.

scholarly journals Terpenoid and carbonyl emissions from Norway spruce in Finland during the growing season

2017 ◽  
Vol 17 (5) ◽  
pp. 3357-3370 ◽  
Author(s):  
Hannele Hakola ◽  
Virpi Tarvainen ◽  
Arnaud P. Praplan ◽  
Kerneels Jaars ◽  
Marja Hemmilä ◽  
...  
Keyword(s):  
Norway Spruce ◽  
Late Summer ◽  
Mean Value ◽  
Emission Rates ◽  
Emission Data ◽  
Emission Pattern ◽  
Mean Values ◽  
Stress Effects ◽  
Ozone Reactivity

Abstract. We present spring and summer volatile organic compound (VOC) emission rate measurements from Norway spruce (Picea abies L. Karst) growing in a boreal forest in southern Finland. The measurements were conducted using in situ gas chromatograph with 1 to 2 h time resolution to reveal quantitative and qualitative short-term and seasonal variability of the emissions. The measurements cover altogether 14 weeks in years 2011, 2014 and 2015. Monoterpene (MT) and sesquiterpene (SQT) emission rates were measured all the time, but isoprene only in 2014 and 2015 and acetone and C4–C10 aldehydes only in 2015. The emission rates of all the compounds were low in spring, but MT, acetone, and C4–C10 aldehyde emission rates increased as summer proceeded, reaching maximum emission rates in July. Late summer mean values (late July and August) were 29, 17, and 33 ng g(dw)−1 h−1 for MTs, acetone, and aldehydes respectively. SQT emission rates increased during the summer and highest emissions were measured in late summer (late summer mean value 84 ng g(dw)−1 h−1) concomitant with highest linalool emissions most likely due to stress effects. The between-tree variability of emission pattern was studied by measuring seven different trees during the same afternoon using adsorbent tubes. Especially the contributions of limonene, terpinolene, and camphene were found to vary between trees, whereas proportions of α-pinene (25 ± 5 %) and β-pinene (7 ± 3 %) were more stable. Our results show that it is important to measure emissions at canopy level due to irregular emission pattern, but reliable SQT emission data can be measured only from enclosures. SQT emissions contributed more than 90 % of the ozone reactivity most of the time, and about 70 % of the OH reactivity during late summer. The contribution of aldehydes to OH reactivity was comparable to that of MT during late summer, 10–30 % most of the time.

Total Energy Expenditure and Physical Activity in Young Chinese Gymnasts

1997 ◽  
Vol 9 (3) ◽  
pp. 243-252 ◽  
Author(s):  
Peter S.W. Davies ◽  
Jian-Ying Feng ◽  
J. Anthony Crisp ◽  
Janice M.E. Day ◽  
Ann Laidlaw ◽  
...  
Keyword(s):  
Physical Activity ◽  
Energy Expenditure ◽  
Total Energy ◽  
Mean Value ◽  
Total Energy Expenditure ◽  
Activity Level ◽  
Free Living ◽  
Mean Values ◽  
Specialized School ◽  
First Time

The energy expenditure and hence energy requirements of 12 young Chinese gymnasts attending a specialized school in Beijing were assessed. Total energy expenditure was measured using the doubly labeled water technique and this, in conjunction with measures of basal metabolic rate (BMR), allows the calculation of a physical activity level (PAL). Mean PAL value for the gymnasts was 1.98, which is significantly different from published mean values found in nongymnast children of a similar age. This mean value is equivalent to very heavy levels of physical activity during the periods of training being undertaken. This is the first time that energy expenditure has been noninvasively measured in free-living young gymnasts. The data will be of use to sports scientists and nutritionists alike.

scholarly journals The influence of <sup>14</sup>CO<sub>2</sub> releases from regional nuclear facilities at the Heidelberg <sup>14</sup>CO<sub>2</sub> sampling site (1986–2014)

2018 ◽  
Author(s):  
Matthias Kuderer ◽  
Samuel Hammer ◽  
Ingeborg Levin
Keyword(s):  
Dispersion Model ◽  
Correction Term ◽  
Sampling Site ◽  
Atmospheric Dispersion ◽  
Mean Value ◽  
Anthropogenic Sources ◽  
Monitoring Site ◽  
Nuclear Facilities ◽  
Wind Fields ◽  
Mean Values

Abstract. Atmospheric Δ14CO2 measurements are a well established tool to estimate regional fossil fuel-derived CO2 fluxes. However, emissions from nuclear facilities can significantly alter the regional Δ14CO2 level. In order to accurately quantify the 14CO2 signal, a correction term for anthropogenic sources has to be determined. In this study, the HYSPLIT atmospheric dispersion model has been applied to calculate the correction term for the long-term 14CO2 monitoring site in Heidelberg. Wind fields with a spatial resolution of 2.5° × 2.5°, 1° × 1° and 0.5° × 0.5° show systematic deviations, with coarser resolved wind fields leading to higher mean values for the correction. The mean correction for the period from 1986–2014, if based on the 0.5° × 0.5° wind field, which we assume as the most accurate, is 2.3 ‰ with a standard deviation of 2.1 ‰ and maximum values up to 15.2 ‰. After ceasing operations at the most important 14CO2 source near Heidelberg in 2011, monthly nuclear correction terms decreased to less than 2 ‰, with a mean value of (0.44 ± 0.32) ‰ from 2012 to 2014.

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