Langjährige Be7 -Bodenluftmessungen lassen Änderung des atmosphärischen Austauschverhaltens während der letzten Jahrzehnte vermuten

1996 ◽  
Vol 51 (10-11) ◽  
pp. 1139-1143 ◽  
Author(s):  
S. Hartwig
Keyword(s):  
Exchange Process ◽  
Ground Level ◽  
Eddy Diffusivity ◽  
Source Distribution ◽  
Air Concentration ◽  
Minimum Concentration ◽  
Exchange Processes ◽  
Yearly Maximum ◽  
Heat Source Distribution ◽  
Ground Level Air

Abstract An analysis covering three decades (1964-1994) of monthly Be7 ground-level-air concentration measurements at Braunschweig shows a systematic trend of the data. This trend is related to the yearly maximum/minimum concentration ratio. The observation may be due to a continuous mitigation of exchange processes between stratosphere and troposphere. This finding is commensurate with the hypothesis that, due to the growing concentration of anthropogenic infrared active gases, the heat source distribution in the stratosphere and consequently the eddy diffusivity and exchange process between stratosphere and troposphere are altered. This results in a shorter irradiation period of stratospheric air portions by cosmic rays and consequently can lower the concentration of isotopes of stratospheric origin in ground level air.

scholarly journals Further Evidence of Changing Stability of the Atmosphere

Radiocarbon ◽  
1995 ◽  
Vol 37 (3) ◽  
pp. 961-962 ◽  
Author(s):  
Sylvius Hartwig
Keyword(s):  
Seasonal Pattern ◽  
Ground Level ◽  
Ozone Layer ◽  
Heat Sources ◽  
Exchange Processes ◽  
Long Term Measurement ◽  
Ground Level Air

In a recent paper (Hartwig, ms.) I have shown that it is possible to understand and discuss the changing Austausch (i.e., exchange of air parcels between different atmospheric layers) between the stratosphere and troposphere by means of long-term measurement of series of spallation products. It is well known (Friend 1961; Müh et al. 1966; Hartwig et al. 1969) that there is a seasonal pattern in the 7Be concentration of ground-level air with a maximum during May–June. This maximum is caused by enhanced exchange processes between the atmospheric compartments of the stratosphere and troposphere during this interval. Generally, those exchange processes are a consequence of stability and dynamics of the atmospheric compartments, which themselves result from, among other factors, the distribution of the heat sources in those compartments, namely the ground and the ozone layer.

Strontium-90, strontium-89, plutonium-239, and plutonium-238 concentrations in ground-level air, 1964-1969

1970 ◽  
Vol 4 (7) ◽  
pp. 598-602 ◽  
Author(s):  
Bernard Shleien ◽  
Joseph A. Cochran ◽  
Paul J. Magno
Keyword(s):  
Ground Level ◽  
Strontium 90 ◽  
Ground Level Air

scholarly journals Assessing Heavy Industrial Heat Source Distribution in China Using Real-Time VIIRS Active Fire/Hotspot Data

2018 ◽  
Vol 10 (12) ◽  
pp. 4419 ◽  
Author(s):  
Caihong Ma ◽  
Jin Yang ◽  
Fu Chen ◽  
Yan Ma ◽  
Jianbo Liu ◽  
...  
Keyword(s):  
Economic Development ◽  
Heat Source ◽  
Infrared Imaging ◽  
Mainland China ◽  
Processing System ◽  
Source Distribution ◽  
Heavy Industry ◽  
Rapid Urbanization ◽  
Active Fire ◽  
Heat Source Distribution

Rapid urbanization and economic development have led to the development of heavy industry and structural re-equalization in mainland China. This has resulted in scattered and disorderly layouts becoming prominent in the region. Furthermore, economic development has exacerbated pressures on regional resources and the environment and has threatened sustainable and coordinated development in the region. The NASA Land Science Investigator Processing System (Land-SIPS) Visible Infrared Imaging Radiometer (VIIRS) 375-m active fire product (VNP14IMG) was selected from the Fire Information for Resource Management System (FIRMS) to study the spatiotemporal patterns of heavy industry development. Furthermore, we employed an improved adaptive K-means algorithm to realize the spatial segmentation of long-order VNP14IMG and constructed heat source objects. Lastly, we used a threshold recognition model to identify heavy industry objects from normal heat source objects. Results suggest that the method is an accurate and effective way to monitor heat sources generated from heavy industry. Moreover, some conclusions about heavy industrial heat source distribution in mainland China at different scales were obtained. Those can be beneficial for policy-makers and heavy industry regulation.

Sulfate and chloride transport in Caco-2 cells: differential regulation by thyroxine and the possible role of DRAgene

2001 ◽  
Vol 280 (4) ◽  
pp. G603-G613 ◽  
Author(s):  
W. A. Alrefai ◽  
S. Tyagi ◽  
F. Mansour ◽  
S. Saksena ◽  
I. Syed ◽  
...  
Keyword(s):  
Cell Line ◽  
Hormonal Regulation ◽  
Competitive Inhibition ◽  
Chloride Transport ◽  
Exchange Process ◽  
Rnase Protection Assay ◽  
Maximum Velocity ◽  
Rnase Protection ◽  
Exchange Processes ◽  
Exchange Activity

The current studies were undertaken to establish an in vitro cellular model to study the transport of SO[Formula: see text] and Cl− and hormonal regulation and to define the possible function of the downregulated in adenoma ( DRA) gene. Utilizing a postconfluent Caco-2 cell line, we studied the OH− gradient-driven35SO[Formula: see text] and 36Cl−uptake. Our findings consistent with the presence of an apical carrier-mediated 35SO[Formula: see text]/OH−exchange process in Caco-2 cells include: 1) demonstration of saturation kinetics [Michaelis-Menten constant ( K m) of 0.2 ± 0.08 mM for SO[Formula: see text] and maximum velocity of 1.1 ± 0.2 pmol · mg protein−1 · 2 min−1]; 2) sensitivity to inhibition by DIDS ( K i = 0.9 ± 0.3 μM); and 3) competitive inhibition by oxalate and Cl−but not by nitrate and short chain fatty acids, with a higher K i (5.95 ± 1 mM) for Cl−compared with oxalate ( K i = 0.2 ± 0.03 mM). Our results also suggested that the SO[Formula: see text]/OH− and Cl−/OH− exchange processes in Caco-2 cells are distinct based on the following: 1) the SO[Formula: see text]/OH− exchange was highly sensitive to inhibition by DIDS compared with Cl−/OH−exchange activity ( K i for DIDS of 0.3 ± 0.1 mM); 2) Cl− competitively inhibited the SO[Formula: see text]/OH− exchange activity with a high K i compared with the K mfor SO[Formula: see text], indicating a lower affinity for Cl−; 3) DIDS competitively inhibited the Cl−/OH− exchange process, whereas it inhibited the SO[Formula: see text]/OH− exchange activity in a mixed-type manner; and 4) utilizing the RNase protection assay, our results showed that 24-h incubation with 100 nM of thyroxine significantly decreased the relative abundance of DRA mRNA along with the SO[Formula: see text]/OH− exchange activity but without any change in Cl−/OH− exchange process. In summary, these studies demonstrated the feasibility of utilizing Caco-2 cell line as a model to study the apical SO[Formula: see text]/OH− and Cl−/OH− exchange processes in the human intestine and indicated that the two transporters are distinct and that DRA may be predominantly a SO[Formula: see text]transporter with a capacity to transport Cl− as well.

Comparison of Beryllium-7 and Cæsium-137 Radioactivity in Ground-Level Air

Nature ◽  
1961 ◽  
Vol 191 (4787) ◽  
pp. 454-456 ◽  
Author(s):  
P. F. GUSTAFSON ◽  
M. A. KERRIGAN ◽  
S. S. BRAR
Keyword(s):  
Ground Level ◽  
Ground Level Air

Radionuclides in deposition in the Ignalina NPP region in 2005

Open Physics ◽  
2006 ◽  
Vol 4 (4) ◽  
Author(s):  
Rimvydas Jasiulionis ◽  
Andrej Rožkov
Keyword(s):  
Nuclear Power ◽  
Particle Deposition ◽  
Activity Concentration ◽  
Ground Level ◽  
137Cs Activity ◽  
Hysplit Model ◽  
Solubility In Water ◽  
137Cs Activity Concentration ◽  
Chernobyl Npp ◽  
Ground Level Air

AbstractResults of radionuclide activity concentration measurements in deposition and ground-level air conducted at the station of the Institute of Physics situated 3.5 km from the Ignalina Nuclear Power Plant (Ignalina NPP) in 2005 are analyzed. Atmospheric depositional fluxes of 7Be, 60Co and 137Cs are estimated. Radionuclide particle deposition rates are calculated. The Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model of the global dispersion and deposition is used to explain variations in the 137Cs activity concentration in the ground-level air in the Ignalina NPP region in 2005. An increase in the 137Cs activity concentration of up to 17.4 µBq m−3 on 30 October-5 November is studied. Modelling results show that the Chernobyl NPP Unit 4 Sarcophagus and the radiocaesium resuspension from the Chernobyl NPP accident polluted regions are sources of 137Cs to the environment of the Ignalina NPP. Results on solubility in water of aerosols — carriers of 137Cs — are discussed.

scholarly journals Uncertainties in assessing the environmental impact of amine emissions from a CO<sub>2</sub> capture plant

2014 ◽  
Vol 14 (16) ◽  
pp. 8533-8557 ◽  
Author(s):  
M. Karl ◽  
N. Castell ◽  
D. Simpson ◽  
S. Solberg ◽  
J. Starrfelt ◽  
...  
Keyword(s):  
Drinking Water ◽  
Environmental Impact ◽  
Lake Water ◽  
Ground Level ◽  
Model Framework ◽  
Study Region ◽  
Fugacity Model ◽  
Modelling Framework ◽  
Degradation Rates ◽  
Ground Level Air

Abstract. In this study, a new model framework that couples the atmospheric chemistry transport model system Weather Research and Forecasting–European Monitoring and Evaluation Programme (WRF-EMEP) and the multimedia fugacity level III model was used to assess the environmental impact of in-air amine emissions from post-combustion carbon dioxide capture. The modelling framework was applied to a typical carbon capture plant artificially placed at Mongstad, on the west coast of Norway. The study region is characterized by high precipitation amounts, relatively few sunshine hours, predominantly westerly winds from the North Atlantic and complex topography. Mongstad can be considered as moderately polluted due to refinery activities. WRF-EMEP enables a detailed treatment of amine chemistry in addition to atmospheric transport and deposition. Deposition fluxes of WRF-EMEP simulations were used as input to the fugacity model in order to derive concentrations of nitramines and nitrosamine in lake water. Predicted concentrations of nitramines and nitrosamines in ground-level air and drinking water were found to be highly sensitive to the description of amine chemistry, especially of the night-time chemistry with the nitrate (NO3) radical. Sensitivity analysis of the fugacity model indicates that catchment characteristics and chemical degradation rates in soil and water are among the important factors controlling the fate of these compounds in lake water. The study shows that realistic emission of commonly used amines result in levels of the sum of nitrosamines and nitramines in ground-level air (0.6–10 pg m−3) and drinking water (0.04–0.25 ng L−1) below the current safety guideline for human health that is enforced by the Norwegian Environment Agency. The modelling framework developed in this study can be used to evaluate possible environmental impacts of emissions of amines from post-combustion capture in other regions of the world.

Assessment of Ultrasonic Welds Using Pulsed Infrared Thermography

2019 ◽  
Vol 2 (1) ◽  
Author(s):  
Megan E. McGovern ◽  
Teresa J. Rinker ◽  
Ryan C. Sekol
Keyword(s):  
Automotive Industry ◽  
Source Distribution ◽  
Quality Inspection ◽  
Battery Cell ◽  
Pulsed Thermography ◽  
Electric Vehicle Battery ◽  
Temporal And Spatial ◽  
Heat Source Distribution ◽  
Metal Welding ◽  
Pulsed Infrared Thermography

Ultrasonic metal welding is used in the automotive industry for a wide variety of joining applications, including batteries and automotive wire harnessing. During electric vehicle battery pack assembly, the battery cell tab and busbar are ultrasonically welded. Quality inspection of these welds is important to ensure durable packs. A method for inspection of ultrasonic welds is proposed using pulsed infrared (IR) thermography in conjunction with electrical resistance measurements to assess the structural and electrical weld integrity. The heat source distribution (HSD) was calculated to obtain thermal images with high temporal and spatial resolution. All defective welds were readily identifiable using three postprocess analyses: pixel counting, gradient image, and knurl pattern assessment. A positive relationship between pixel count and mechanical strength was observed. The results demonstrate the potential of pulsed thermography for inline inspection to assess weld integrity.

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