scholarly journals Decoupling of ground level pressures observed in Italian volcanoes: are they driven by space weather geo-effectiveness?

2014 ◽  
Vol 57 (3) ◽  
Author(s):  
Paolo Madonia ◽  
Paolo Romano ◽  
Salvatore Inguaggiato
Keyword(s):  
Space Weather ◽  
Atmospheric Pressure ◽  
Pressure Field ◽  
Ground Level ◽  
Total Solar Irradiance ◽  
Weather Parameters ◽  
Sun Activity ◽  
Fft Analysis ◽  
Sunspot Groups

<p>Investigations on correlation drops between near-ground atmospheric pressures measured at sea level and at higher altitudes on Italian volcanoes have been carried out. We looked for perturbations of the atmospheric pressure field driven by volcanic activity, but not excluding possible external triggers for the observed anomalies. Decorrelations between atmospheric pressures measured at Stromboli Island in stations located at different altitudes (years 2002-10) have been analysed and compared with data from other volcanic (Vesuvius) and non volcanic (Mt. Soro) orographic structures. We investigated as their possible triggers volcanic, meteorological and space weather parameters, with particular attention to Total Solar Irradiance (TSI), Kp index and Forbush decreases. Pressure decorrelations seems to be driven by astronomic cycles, with maxima in summer and minima in winter. A further contribution was found, seemingly assignable to TSI anomalies, with correlation minima occurring 12 hours after these but only during phases of high Sun activity. Moreover, during the same phases a main periodicity of about 27 days in pressure decorrelations was revealed by FFT analysis. This period is the same of the Sun Carrington rotation, expressing the periodic reappearance of sunspot groups on Sun’s surface. The strong similarity between recurrences of sunspot number and atmospheric pressure anomalies further supports the role of the former as a possible trigger for the latter.</p>

scholarly journals Ozone concentration in ground-level air layer in north-western Poland - The role of meteorological elements

2009 ◽  
Vol 41 (1) ◽  
pp. 19-39
Author(s):  
Robert Kalbarczyk ◽  
Eliza Kalbarczyk
Keyword(s):  
Ozone Concentration ◽  
Atmospheric Pressure ◽  
Ground Level ◽  
Total Solar Radiation ◽  
Air Humidity ◽  
Relative Air Humidity ◽  
Meteorological Elements ◽  
North Western ◽  
Ground Level Air

Ozone concentration in ground-level air layer in north-western Poland - The role of meteorological elements The research aimed at recognising time structure and variability of tropospheric ozone as a function of daytime and nocturnal meteorological conditions, particularly in the spring season (March-May), as well as finding a weather cluster at which the highest O3 concentration occurs. Ozone concentrations recorded every hour during the two years and data on five other meteorological elements: total solar radiation, air temperature, relative air humidity, atmospheric pressure, wind direction and speed provided the input data for the analysis. The data were collected at Widuchowa weather station, north-western Poland, near the Polish-German border. The highest ozone concentration was observed at daytime day, under conditions of eastern wind, low relative air humidity (about 35%), high values of total solar radiation (about 209 W·m-2), air temperature (17.0°C), atmospheric pressure (1016 hPa) and high wind speed (2.7 m·s-1). It is concluded that the magnitude of tropospheric ozone concentration recorded at Widuchowa is influenced by gaseous pollutants originating not only from the territory of Poland but also from Germany.

Microstructure and reactivity of small metal particles: The role of Ce additives

1992 ◽  
Vol 50 (1) ◽  
pp. 318-319
Author(s):  
L.D. Schmidt ◽  
K. R. Krause ◽  
J. M. Schwartz ◽  
X. Chu
Keyword(s):  
Atmospheric Pressure ◽  
Noble Metals ◽  
Mixed Oxides ◽  
Catalytic Properties ◽  
Chemical Shifts ◽  
Catalytic Converter ◽  
Structural Evolution ◽  
Single Particles ◽  
Small Metal Particles

The evolution of microstructures of 10- to 100-Å diameter particles of Rh and Pt on SiO2 and Al2O3 following treatment in reducing, oxidizing, and reacting conditions have been characterized by TEM. We are able to transfer particles repeatedly between microscope and a reactor furnace so that the structural evolution of single particles can be examined following treatments in gases at atmospheric pressure. We are especially interested in the role of Ce additives on noble metals such as Pt and Rh. These systems are crucial in the automotive catalytic converter, and rare earths can significantly modify catalytic properties in many reactions. In particular, we are concerned with the oxidation state of Ce and its role in formation of mixed oxides with metals or with the support. For this we employ EELS in TEM, a technique uniquely suited to detect chemical shifts with ∼30Å resolution.

scholarly journals A 3D study on the amplification of regional haze and particle growth by local emissions

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Wei Du ◽  
Lubna Dada ◽  
Jian Zhao ◽  
Xueshun Chen ◽  
Kaspar R. Daellenbach ◽  
...  
Keyword(s):  
Atmospheric Stability ◽  
Ground Level ◽  
Particle Growth ◽  
Chemical Compositions ◽  
Size Distributions ◽  
Aerosol Composition ◽  
Regional Haze ◽  
Haze Formation ◽  
Beijing China

AbstractThe role of new particle formation (NPF) events and their contribution to haze formation through subsequent growth in polluted megacities is still controversial. To improve the understanding of the sources, meteorological conditions, and chemistry behind air pollution, we performed simultaneous measurements of aerosol composition and particle number size distributions at ground level and at 260 m in central Beijing, China, during a total of 4 months in 2015–2017. Our measurements show a pronounced decoupling of gas-to-particle conversion between the two heights, leading to different haze processes in terms of particle size distributions and chemical compositions. The development of haze was initiated by the growth of freshly formed particles at both heights, whereas the more severe haze at ground level was connected directly to local primary particles and gaseous precursors leading to higher particle growth rates. The particle growth creates a feedback loop, in which a further development of haze increases the atmospheric stability, which in turn strengthens the persisting apparent decoupling between the two heights and increases the severity of haze at ground level. Moreover, we complemented our field observations with model analyses, which suggest that the growth of NPF-originated particles accounted up to ∼60% of the accumulation mode particles in the Beijing–Tianjin–Hebei area during haze conditions. The results suggest that a reduction in anthropogenic gaseous precursors, suppressing particle growth, is a critical step for alleviating haze although the number concentration of freshly formed particles (3–40 nm) via NPF does not reduce after emission controls.

scholarly journals Effects of Ambient Pressure on the Instability of a Liquid Boiling Explosively at the Superheat Limit

1986 ◽  
Vol 108 (2) ◽  
pp. 418-424 ◽  
Author(s):  
D. Frost ◽  
B. Sturtevant
Keyword(s):  
Atmospheric Pressure ◽  
Bubble Growth ◽  
Absolute Stability ◽  
Pressure Field ◽  
Ambient Pressure ◽  
Small Temperature ◽  
Instability Theory ◽  
Two Stages ◽  
Single Droplets ◽  
Superheat Limit

The effect of ambient pressure on the intrinsic instability of rapid vaporization in single droplets boiling explosively at the limit of superheat has been studied experimentally and theoretically. The instability that distorts the evaporating interface and substantially enhances the mass flux at atmospheric pressure is suppressed at high pressure. The radiated pressure field is two orders of magnitude smaller from stabilized bubbles than from unstable. At intermediate pressures bubble growth occurs in two stages, first stable, then unstable. The Landau–Darrieus instability theory predicts absolute stability at atmospheric pressure for a spherical bubble, whereas the theory for planar interfaces yields results in general agreement with observation. The sensitivity of the instability to temperature suggests that small temperature nonuniformities may be responsible for quantitative departures of the behavior from predictions.

scholarly journals The role of ammonia in sulfuric acid ion induced nucleation

2008 ◽  
Vol 8 (11) ◽  
pp. 2859-2867 ◽  
Author(s):  
I. K. Ortega ◽  
T. Kurtén ◽  
H. Vehkamäki ◽  
M. Kulmala
Keyword(s):  
Sulfuric Acid ◽  
Quantum Chemical ◽  
Local Minimum ◽  
Good Accuracy ◽  
Energy Surface ◽  
Ground Level ◽  
Computational Effort ◽  
Free Energy Surface ◽  
Large Clusters

Abstract. We have developed a new multi-step strategy for quantum chemical calculations on atmospherically relevant cluster structures that makes calculation for large clusters affordable with a good accuracy-to-computational effort ratio. We have applied this strategy to evaluate the relevance of ternary ion induced nucleation; we have also performed calculations for neutral ternary nucleation for comparison. The results for neutral ternary nucleation agree with previous results, and confirm the important role of ammonia in enhancing the growth of sulfuric acid clusters. On the other hand, we have found that ammonia does not enhance the growth of ionic sulfuric acid clusters. The results also confirm that ion-induced nucleation is a barrierless process at high altitudes, but at ground level there exists a barrier due to the presence of a local minimum on the free energy surface.

IOT Based Self Vehicle Pollution Checking, Engine Temperature and Fuel Levels with Prediction Alerts

2021 ◽  
Vol 9 (VII) ◽  
pp. 212-220
Author(s):  
G. Naveen Kumar
Keyword(s):  
Internet Of Things ◽  
Atmospheric Pressure ◽  
Geographical Area ◽  
The Internet ◽  
Information Mining ◽  
Simple Idea ◽  
Remote Sensors ◽  
Pollution Detection ◽  
Weather Parameters ◽  
Vehicle Pollution

Pollution detection and ordinary tracking is extraordinarily good-sized errand in this point in time of in our present international. To make a higher and greater steady circumstance for individual, creatures, and plants. We ought to display screen and manage the infection via the Internet of factors innovation. This research proposes air infection and checking version which distinguishes infection in air primarily based totally on statistics mining calculation. The sensor System is used to apprehend the sensor regards from one of a kind fueloline sensors. The microcontroller is applied to trade the features from ADC to server. Information mining is applied to compute the pollution from numerous regions. ID3 set of rules is used to figuring the bottom of the traits on probability. Bluetooth module is applied to interface the controller with the purchaser and the purchaser related to the server via internet administrations. Remote sensors are applied to envision the extent of risky gases gives major all-round that, at last, offers a lower in infection. This framework now no longer simply computes the poisons gift major all-round yet, in addition, we are able to parent to preserve a strategic distance from destiny infection in and might ship the notification message to the particular dirtied location. Here we recall essentially the concoction Industry near Delhi and the metro city groups.These studies paper in particular centered at the evidence of pollutants tracking and locate on precise region or geographical area for an IOT bodily devices that collects statistics with admire to bodily parameters, making use of a complicated microcontroller stage, from one of a kind varieties of sensors, via various techniques of correspondence and after that transfers the statistics to the an internet. The displayed device has been supposed for far flung checking of weather numerous environments. These article facilities across the approach of moving received statistics at the internet with the intention that the device may be applied to remotely display screen weather parameters and in the end take a look at environmental extrade designs like temperature, humidity, Atmospheric Pressure. The paper additionally discusses the simple idea of Internet of Things and its capacity programs, specially for climate tracking.

scholarly journals Influence of the ambient humidity on the concentration of natural deposition-mode ice-nucleating particles

2016 ◽  
Vol 16 (2) ◽  
pp. 927-932 ◽  
Author(s):  
M. L. López ◽  
E. E. Ávila
Keyword(s):  
Relative Humidity ◽  
Linear Trend ◽  
Ground Level ◽  
Ambient Air ◽  
Air Masses ◽  
Ambient Relative Humidity ◽  
Thermodynamic Conditions ◽  
Rainy Days ◽  
Deposition Mode

Abstract. This study reports measurements of deposition-mode ice-nucleating particle (INP) concentrations at ground level during the period July–December 2014 in Córdoba, Argentina. Ambient air was sampled into a cloud chamber where the INP concentration was measured at a temperature of −25 °C and a 15 % supersaturation over ice. Measurements were performed on days with different thermodynamic conditions, including rainy days. The effect of the relative humidity at ground level (RHamb) on the INP concentration was analyzed. The number of INPs activated varied from 1 L−1 at RHamb of 25 % to 30 L−1 at RHamb of 90 %. In general, a linear trend between the INP concentration and the RHamb was found, suggesting that this variability must be related to the effectiveness of the aerosols acting as INPs. From the backward trajectories analysis, it was found that the link between INP concentration and RHamb is independent of the origin of the air masses. The role of biological INPs and nucleation occurring in pores and cavities was discussed as a possible mechanism to explain the increase of the INP concentration during high ambient relative humidity events. This work provides valuable measurements of deposition-mode INP concentrations from the Southern Hemisphere where INP data are sparse so far.

scholarly journals The influence of argon gas flow in the killing of staphylococcus epidermidis bacteria

2018 ◽  
Vol 16 (36) ◽  
pp. 134-139
Author(s):  
Ahmed Mahmoud Shihab
Keyword(s):  
Staphylococcus Epidermidis ◽  
Atmospheric Pressure ◽  
Gas Flow ◽  
Biotechnological Applications ◽  
Plasma System ◽  
Argon Gas ◽  
Killing Rate ◽  
Normal Atmospheric Pressure ◽  
Non Thermal Plasma

In this research, non-thermal plasma system of argon gas is designed to work at normal atmospheric pressure and suitable for work in medical and biotechnological applications. This technique is applied in the treatment of the Staphylococcus epidermidis bacteria and show the role of the flow rate of Argon gas on the killing rate of bacteria, and it obtained a 100 % killing rate during the time of 5 minutes at the flow Argon gas of 5 liters/ min.

Sign in / Sign up

Export Citation Format

Share Document