For the calorimetric determination of the primary energy of extensive air showers, measured by fluorescence telescopes, a precise knowledge of the conversion factor (fluorescence yield) between the deposited energy in the atmosphere and the number of emitted fluorescence photons is essential. The fluorescence yield depends on the pressure and the temperature of the air as well as on the water v...

to analysis the mechanisms of blocking high effects on heavy precipitations in northwest of iran, we selected a short period of heavy precipitation (25-28 october 2008). in this case, weather maps such as mean of sea level pressure, 850-hpa and 500-hpa geopotential height levels were assessed and analyzed for the whole period. the position and movement of the atmospheric systems such as cyclone...

Abstract A spectral analysis of Great Plains 850-hPa meridional winds (V850) from ECMWF’s coupled climate reanalysis 1901–2010 (CERA-20C) reveals that their warm season (April–September) interannual variability peaks in May with 2–6-yr periodicity, suggestive an underlying teleconnection influence on low-level jets (LLJs). Using objective, dynamical jet classification framework based 500-hPa wa...

Abstract A novel method that quantitatively evaluates the development processes of extratropical cyclones is devised and applied to explosive over Northwest Pacific in cold season (October–April). By inverting potential vorticity (PV) tendency equation, contribution dynamic thermodynamic at different levels cyclone quantified. In terms geostrophic 850 hPa, which utilized quantify development, l...

The high temperature oxidation behaviour of Nimonic-115 industrial alloy has been investigated in presence of  NaNO3, Na2CO3 and Na2O2 at 850oC in flowing air. The oxidation kinetics and effect of salt deposition for the period of 48 h were studied. The scale morphologies were determined on the basis of X-ray diffraction anal...

Heatwaves are an extreme meteorological event in which affected populations may also be exposed to deteriorated air quality conditions due the increase pollutant concentrations, such as PM10 (particulate matter < 10 µg/m3). In order identify heatwaves (1973–2019) region of Faro (Algarve) during hot season (April–September), Excess Heat Factor (EHF) index was applied. The Mann–Kendall test re...

Abstract A k- means clustering method is applied to daily ERA5 500-hPa heights, sea level pressure, and 850-hPa winds, 1979–2008, identify characteristic weather types (WTs) for September–November the northeast United States. The resulting WTs are analyzed in terms of structure, frequency occurrence, typical progressions, precipitation temperature characteristics, relation teleconnections. used...

Mechanosynthesis of La1-xSrxMnO3 (x = 0, 0.25, 0.5, 0.75 and 1) was carried out at room temperature from stoichiometric mixtures of La2O3, Mn2O3 and SrO, obtaining monophasic powders with the perovskite structure. Physical properties of these materials and their chemical compatibility with the electrolyte yttria stabilized zirconia (YSZ), which depend strongly on the La/Sr ratio, were evaluated...

The most striking feature of the general circulation of April 1954 was the extremely strong poleward temperature gradient which prevailed dong the northern border of the United States, as indicated by the zonal orientation and crowding of isotherms in this area on the monthly mean charts for sea level (Chart I-A) and upper levels from 850 to 300 mb. (Charts XII-XV). The anomalies of temperature...

Calcium hydroxyapatite (HA) whiskers and crystals were produced by the route of molten salt synthesis. The effects on whisker morphology of chosen flux, flux-to-HA ratio, synthesis temperature, and reaction time were investigated. The thermal stabilities of the produced whiskers were tested at 1300°C in an air atmosphere. A tentative X-ray diffraction pattern was proposed for the HA whiskers. M...