scholarly journals Composition of Organic Carbon-Based Compounds in the Stem Wood of Quercus mongolica Seedlings Grown Under Elevated CO2 and/or O3 Concentrations

2021 ◽  
Vol 4 ◽  
Author(s):  
Shin Ugawa ◽  
Shoji Hashimoto ◽  
Koh Hashida ◽  
Hiroyuki Tobita ◽  
Mitsutoshi Kitao
Keyword(s):  
Ambient Air ◽  
Extractive Content ◽  
Air Concentration ◽  
Woody Tissue ◽  
Quercus Mongolica ◽  
Stem Wood ◽  
Organic Constituents ◽  
Free Air ◽  
Air Control ◽  
Concentration Condition

In this study, we examined the composition of organic constituents of stem woody tissue together with tree growth in Quercus mongolica var. grosseserrata Blume seedlings raised under controlled CO2 and/or O3 concentrations in a Free-Air Concentration Enrichment system. After exposure to ambient air (control), elevated CO2 concentration (550 μmol mol–1 CO2), elevated O3 concentration (double that of the control), and a combination of elevated CO2 and O3 concentrations during a growing season, we measured the diameter and length of stem, and biomass of sampled seedlings and quantified the lignin, extractive, and holocellulose contents of the woody tissue of current-year stems. We confirmed that the growth of seedlings was enhanced under an elevated CO2 concentration condition. In line with this, the extractive content was lower in woody tissue formed under an elevated CO2 concentration than that formed under ambient air, whereas holocellulose content showed an inverse pattern. Elevated O3 concentration itself did not change the organic constituents of the woody tissue, but it reduced the influence of an elevated CO2 concentration. We thus assume that Q. mongolica formed woody tissue with a low extractive content under the high CO2 concentration condition, although this response was possibly mitigated by an elevated O3 concentration. Extractives contains antimicrobial components such as tannins, flavonoids, quinones, and terpenoids. The decrease in extractives within the widely distributed Q. mongolica in East Asia may have a non-negligible impact on C cycling in the future earth with high atmospheric CO2 concentration.

Characteristics of Photosynthesis in Wheat Cultivars with Different Sensitivities to Ozone Under O3-Free Air Concentration Enrichment Conditions

2009 ◽  
Vol 35 (8) ◽  
pp. 1500-1507
Author(s):  
Ji-Ling CAO ◽  
Liang WANG ◽  
Qing ZENG ◽  
Jing LIANG ◽  
Hao-Ye TANG ◽  
...  
Keyword(s):  
Wheat Cultivars ◽  
Air Concentration ◽  
Free Air

Optical Patternation of Gas Turbine Fuel Sprays During Simulated Engine Operating Conditions

2009 ◽  
Author(s):  
S. R. D. Guy ◽  
W. D. E. Allan ◽  
Marc LaViolette ◽  
P. R. Underhill
Keyword(s):  
Gas Turbine ◽  
Ambient Air ◽  
Operating Conditions ◽  
Test Apparatus ◽  
Test Rig ◽  
Transport Aircraft ◽  
Test Conditions ◽  
Free Air ◽  
Primary Zone ◽  
Future Experimentation

Fuel atomizer condition can have a significant impact on gas turbine hot section component life. In order to investigate the depth of this influence, an experimental test apparatus was constructed, which allowed for optical access to the primary zone of a Rolls-Royce/Allison T56–A–15 turboprop combustion chamber. Test conditions were matched to simulate altitude cruise conditions of a C–130H Hercules military transport aircraft. T56 fuel nozzles of various conditions were tested in free air and then in the test rig using optical patternation techniques. Results indicated that spray characteristics observed in quiescent ambient air persisted under the representative engine operating conditions both burning and non-burning. The optical patternation tests also revealed the influence of combustion liner airflow patterns on the spray within the region of the primary zone that was observed. Conclusions were drawn such as the persistence of spray features observed in open air testing when nozzles were tested at engine representative conditions and recommendations were made for future experimentation.

scholarly journals Health Risk Associated with Near-Road Ambient Air Concentration of Particulate Matter in Mukono Municipal Council, Uganda

2021 ◽  
Vol 9 (1) ◽  
pp. 127-137
Author(s):  
Edward Kibikyo Mukooza
Keyword(s):  
Air Pollution ◽  
Health Risk ◽  
Ambient Air ◽  
Air Concentration ◽  
Middle Income ◽  
Middle Income Countries ◽  
Premature Deaths ◽  
Increased Risk ◽  
The Mean ◽  
Pm2.5 Concentration

More than 98% of urban centres exceeding 100,000 people in Low and Middle-Income Countries (LMICs), do not meet the WHO air quality limits. Data on air pollution from LMICs is scarce. We measured the mean concentrations of near-road PM2.5 in the period of Aug.-Dec. 2020, described the Mukono Municipality’s near-road populations’ exposure to PM2.5, and assessed the associated health risk. PurpleAir PA-II laser particle counters, measured near-road ambient air PM2.5 concentration in Mukono Municipality during the period of 09/1/20 to 12/04/20. Excel Toolpak was used for data analysis and the health risk assessed with the WHO AirQ+ tool. The mean ambient near–road PM2.5 in Mukono Municipality were 30.97, 33.84 and 47.74 ug/m3for background, near-unpaved and near-paved roads, respectively. Mukono Municipality’s population was exposed to ambient PM2.5 concentrations higher than the WHO annual limit of 10 ug/m3. This level of air pollution is associated with preventable annual premature deaths of up to 133.11 per 100,000 population. Vehicles were assumed to be the predominant source of near-road ambient air PM2.5 pollution. The Municipality’s population was exposed to near-road ambient air PM2.5 exceeding the WHO annual limit by as much as *4.7 for the paved roads, *3.3 for the unpaved roads and *3 for the background. This leads to increased risk of preventable premature deaths in the Municipality.Mukono Municipality could monitor PM2.5; guide developers to placebuildings more than 100 meters away from roadsides and should promotepolicies for newer vehicles on Ugandan roads.

scholarly journals Using Hexanal Vapor to Inhibit Activity of Penicillium expansum in Inoculated Whole Apple Fruit

HortScience ◽  
1997 ◽  
Vol 32 (3) ◽  
pp. 536F-537
Author(s):  
Lihua Fan ◽  
Jun Song ◽  
Randolph Beaudry
Keyword(s):  
Decay Rate ◽  
Fungal Growth ◽  
Apple Fruit ◽  
Penicillium Expansum ◽  
Aroma Volatiles ◽  
Free Air ◽  
Air Control ◽  
And Control ◽  
Cessation Of Treatment ◽  
Treated Apple

Hexanal vapor is a natural, metabolizable fungicide that inhibits fungal activity and enhances the aroma biosynthesis in sliced apple fruit. Whole apple fruit were inoculated at two points per fruit with Penicillium expansum at a concentration of 0.5 × 105 spore/ml and treated with hexanal vapors. Inoculated fruit were exposed to hexanal for 48 hr and kept for another 72 hr in hexanal-free air at 22°C. Treatments included 8.2–12.3 μmol·L–1 (200–300 ppm), 14.5-18.6 μmol·L–1 (350–450 ppm), and 24.8-28.9 μmol·L–1 (600–700 ppm), each with an air control. At a concentration of 200–300 ppm hexanal, there was no fungal growth during treatment, but lesion development was evident on 100% of the treated fruit following cessation of treatment. After 72 hr holding in air, lesion diameter was significantly smaller for treated fruit. When inoculated apple fruit were exposed to 350–450 ppm and 600–700 ppm hexanal vapors, the decay rate was 44.7% and 23.9%, respectively, while the decay rate of inoculated control apple fruit was 100% and 98%, respectively, after 72 hr holding in air. The development of aroma volatiles was investigated for both treated and untreated whole apple fruit. Hexanal was actively converted to aroma volatiles by `Golden Delicious' fruit and there was no detectable hexanal emanations. The amount of hexylacetate, hexylbutanoate, hexylhexanoate, hexylpropionate, butylhexanoate, and hexyl-2-methybutanoate were about 2- to 4-fold higher in treated apple fruit than in untreated apple fruit. `Mutsu' apple fruit were treated with 350–450 ppm hexanal for 48 hr and processed into apple sauce within 4 hr. An informal sensory evaluation for processed `Mutsu' apple revealed no apparent flavor difference between treated and control fruit sauce.

scholarly journals Determination of the best interpolation method in estimating the concen-tration of environmental air pollutants in Tehran city in 2015

2019 ◽  
Author(s):  
Akbar Eslami ◽  
Seyed Mehdi Ghasemi
Keyword(s):  
Interpolation Method ◽  
Ambient Air ◽  
Air Concentration ◽  
Pearson Coefficient ◽  
Distance Weighted ◽  
Kolmogorov Smirnov ◽  
Environmental Air ◽  
Inverse Distance ◽  
Better Than

Introduction: Air pollution is one of the important issues in developing coun-tries, due to increased population and industrialization. In this research, the spatial distribution of ambient air concentration such as CO, NO2, SO2, PM2.5, PM10, O3 and Air quality Index (AQI) in Tehran city in 2015 were evaluated using different deterministic ( inverse distance weighted, local polynomial, global polynomial, radial basis functions) and geostatistical (Kriging, Cokrig-ing) methods.   Materials and methods: Root Mean Square Error (RMSE) and Mean Error (ME) using cross-evaluation methods were used to control the accuracy of the interpolation. To find the secondary variables in the cokriging method, the Pearson coefficient of each pollutant was calculated with another pollutant.   Results: The Kolmogorov-Smirnov test showed that all data followed normal distribution. Also the results indicated that in most cases, geostatistical meth-ods were the best methods to estimate ambient air concentration. Finally, after selecting the best interpolation method, the zoning map of the pollutant was drawn with ArcGIS.   Conclusion: The results of 71 methods showed that in most cases, the geosta-tistical method is better than the deterministic method

scholarly journals BEBAN EMISI AKTIVITAS LTO PESAWAT UDARA DI BANDAR UDARA INTERNASIONAL I GUSTI NGURAH RAI BALI

2015 ◽  
Vol 9 (1) ◽  
pp. 72 ◽  
Author(s):  
Yohanis Umbu Kaleka ◽  
I Wayan Budiarsa Suyasa ◽  
M.S. Mahendra
Keyword(s):  
Ambient Air ◽  
Quality Standard ◽  
Activity Level ◽  
The Other ◽  
Air Concentration ◽  
Gas Emission ◽  
International Airport ◽  
Statistical Analysis Method ◽  
Emission Activity ◽  
Co Emission

I Gusti Ngurah Rai Bali International Airport is the second highest airport in activity level in Indonesia. Flight activity in this airport increases every year, with an increase of 20% from 2011 until the end of 2012. The research aimed to identify how much the LTO (Landing-Take-Off) emission activity in I Gusti Ngurah Rai Bali International Airport. The purpose of this research was to identify how much the emission is and the effect of LTO activities towards the ambient air condition of CO and NOx around the airport. Three measurement points and three days recent flight were applied to understand the emission spreading characteristic in every LTO phases. The three phases of LTO which are consisted of take-off phase, taxi in phase and landing phase, were the main focus of this research. The three recent flights were on Monday 5 of May, on Wednesday 7 of May and on Saturday 10 of May in 2014. Regression bifilar linear statistical analysis method was employed to identify the effect and how big the CO and NOx emission contribution towards the ambient air quality. The results of this research showed that the emission of aircraft activity in LTO phases was effected by the ambient air concentration of CO and NOx. It was proved with the result from F test simultaneous with significant level average 0,033 < 0,005 and with r value that exists between 0,77 – 0,97 with mean contribution was 79,1%. Take-off phase was the phase that produced the biggest NOx gas emission compared to the other phases. When the aircraft did the take-off phase, the thrust was used reached 100%, the purpose was to produce the big energy. The combustion that happened in take-off phase in aircraft machine classified in perfect combustion, also this thing effected the phase to produce the smallest CO gas emission compared with the other phases. Taxi in phase was a phase that produced the biggest CO emission between the two other phases, it was happened because the thrust needed just 7% only so the combustion in aircraft machine classified in imperfect combustion and it was effected the CO emission was increasingly while the landing phase was the phase that produced the smallest CO and NOx gas emission compared to the other phases. Measurement results of the CO and NOx concentration in every point in three days recent flight was still under the quality standard that has been settled appropriate in Government Act number 41 year 1999..

scholarly journals The Structure of Thermals in Cumulus from Airborne Dual-Doppler Radar Observations

2006 ◽  
Vol 63 (5) ◽  
pp. 1432-1450 ◽  
Author(s):  
Rick Damiani ◽  
Gabor Vali ◽  
Samuel Haimov
Keyword(s):  
Doppler Radar ◽  
Ambient Air ◽  
Velocity Fields ◽  
Vertical Shear ◽  
Vortex Rings ◽  
Interface Instability ◽  
Cloud Radar ◽  
Free Air ◽  
Ring Core

Abstract A newly developed technique for airborne dual-Doppler observations with the Wyoming Cloud Radar is used to characterize the velocity fields in vertical planes across cumulus turrets. The clouds sampled were continental in nature, with high bases (near 0°C) and with depths of 2–3 km. Clear evidence was found that the clouds evolved through sequences of bubbles, or thermals, with well-defined toroidal circulations, or vortex rings. The ring core and tube diameters were about 200–600 m, leading to turret sizes of 1–2 km in the horizontal. The largest updraft speeds were observed in the ring centers, but regions of turbulent, ascending air extended behind the thermals to distances comparable with the toroid sizes. Vertical shear of ambient winds, when present, led to a tilting of the updrafts and toroids. Patterns in the reflectivity and velocity fields indicated regions of major intrusions into the thermals, accompanied by entrainment of ambient air, or recycling of larger hydrometeors, depending on their location. In addition, at the upper cloud/environment interface, instability nodes contributed to further entrapment of cloud-free air. The observations presented in this paper constitute clear demonstrations and quantitative characterization of vortical circulations in growing cumulus turrets; they should provide a more reliable basis for the assessment of simulations and of model parameterizations.

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