potassium-argon analysis by stqwise dissolution provides a way to measure in detail the distribution of argon isotopes and potassium in rock salt. the method can be used for salt that contains only trace amounts of potassium, because the potassium and argon in detrital silicates within the salt are not released during the dissolution. water may be used as the solvent when relatively large amoun...

For the first time we apply a new method based on the mathematical derivation of some known isotherm from the Burr function which describes many birth-death (sorption-desorption) phenomena in ecology and economy. Therefore, in this study the experimental isotherm data of biosorption of Pb(II) onto algae was modeled to Langmuir, Hill-Sips, Brouers-Sotolongo, BrouersGaspard, and Redlich-Peterson ...

Parameters from single-component isotherm models were used in multicomponent isotherm models to predict the aqueous phase sorption of trichloroethylene (TCE) in the presence of tetrachloroethylene (PCE) in four zeolites, Tenax, and three natural solids. The Langmuir, the Polanyi-Dubinin, and the Freundlich or the Langmuir-Freundlich isotherm models were used to simulate single-component sorptio...

A new method for the measurement of argon isotope composition in a continuous flow of helium for potassium/argon geochronology is described. Extraction of argon from geological samples in multiple-sample holders was carried out in a chamber by heating with a continuous Nd-YAG laser. The extracted and pre-concentrated argon is passed through a chromatographic capillary column in a flow of helium...

Emission spectra of constituent gas species from glow discharge plasmas using argon-helium, krypton-helium, argon-krypton, and krypton-argon gas mixtures were analyzed to elucidate collisional energy transfer between these gas species occurring in the plasma. In the argon-helium mixed gas plasma, the enhancement or quenching of particular Ar II lines was observed when helium was added to an arg...

Numerical calculations are reported which simulate atmospheric-pressure radiofrequency induction plasmas consisting of either pure argon or mixtures of argon with hydrogen, nitrogen, or oxygen. These calculations are compared to observations of laboratoo, plasmas generated with the same geometrr and run conditions. The major features of the laboratory plasmas are predicted well by the calculati...

background: endoscopic therapies can decrease the morbidity of patients with high risk peptic ulcer. the aim of this study was to evaluate the beneficial effects of oral omeprazole therapy in patients with bleeding peptic ulcer who received combined endoscopic treatment (epinephrine injection and argon plasma coagulation). materials and methods: eighty six patients with bleeding from gastric, d...

In vitro studies have well established the neuroprotective action of the noble gas argon. However, only limited data from in vivo models are available, and particularly whether postexcitotoxic or postischemic argon can provide neuroprotection in vivo still remains to be demonstrated. Here, we investigated the possible neuroprotective effect of postexcitotoxic-postischemic argon both ex vivo in ...

Introduction: The idea of stable deposits of volatiles in cold permanently shaded regions (PSRs), first advanced by [1], has been revived since observations by Lunar Prospector suggested large amounts of hydrogen in the polar caps. Previous studies have mainly focused on hydrogen (and water) [2] but other important volatiles such as argon could also be trapped. Temperatures in the coldest regio...

During the last half of the twentieth century, the argon-argon method of dating geologic rocks and formations became very popular. This method replaced K/Ar as the method of choice for many types of rocks. This paper explores the fundamental mathematics of the argon-argon dating method and evaluates the impact of the assumed date of the “standard sample” on the calculated argon-argon date. A me...