Developmental Studies of Potential Chemically Pumped Electronic Transition Lasers: Combustion of Alkaline Earths in Nitrous Oxide-Carbon Monoxide and Reactions of Metastable Alkaline Earth Atoms.

1978 ◽  
Author(s):  
David J. Benard ◽  
Warren D. Slafer ◽  
Paul H. Lee
Keyword(s):  
Carbon Monoxide ◽  
Nitrous Oxide ◽  
Electronic Transition ◽  
Alkaline Earth ◽  
Developmental Studies ◽  
Alkaline Earths ◽  
Electronic Transition Lasers

Dichlorosilylene: Rate constant for reaction with carbon monoxide and nitrous oxide

1989 ◽  
Vol 11 (3) ◽  
pp. 235-244 ◽  
Author(s):  
V. Sandhu ◽  
O. P. Strausz ◽  
T. N. Bell
Keyword(s):  
Carbon Monoxide ◽  
Nitrous Oxide ◽  
Rate Constant

Weathering mineral facies in altered granites: The importance of local small-scale equilibria

1979 ◽  
Vol 43 (326) ◽  
pp. 261-268 ◽  
Author(s):  
A. Meunier ◽  
B. Velde
Keyword(s):  
Chemical Composition ◽  
Alkaline Earth ◽  
Clay Mineralogy ◽  
Small Scale ◽  
Chemical Potentials ◽  
Silica Activity ◽  
Section Size ◽  
Alkaline Earths ◽  
Last Stage ◽  
Rock Alteration

SummaryClassical clay mineralogy determinations and electron microprobe analyses of weathering minerals developed in altered two-mica granites indicate that the chemical forces that produce new minerals are often constrained to small volumes, frequently on the scale of a mineral grain or contact between two grains in the granite.Chemical potentials such as pH, alkali and alkaline earth and silica activity in the altering aqueous solutions provoke a destabilization of pre-existing minerals, which recrystallize locally to give a new multimineral product. The chemical composition of the new phases is largely governed by the relative concentrations of the elements present in the former minerals.Three mineral facies were observed in the weathered granites: initially a sericite-beidellitic type, then a beidellite-kaolinitic type, and finally a last stage kaolinite-oxide facies assemblage. The position of each facies is not restricted to a given depth in the profile but the relative proportions of each facies found in a thin-section size sample change towards the kaolinite-oxide facies.The global rock chemistry reflects the type facies predominant in each sample. The first two facies are roughly silica conservative while the kaolinite-oxide facies loses silica as well as alkali and alkaline earths.Geochemical and clay mineral studies of rock alteration should consider problems of mineral genesis at very localized sites.

GLASS STABILITY EFFECT OF IRON OXIDE ADDED TO ALKALINE EARTH BORATE GLASSES

2007 ◽  
Vol 21 (05) ◽  
pp. 731-736
Author(s):  
V. SIMON ◽  
P. RIEDL ◽  
E. TATARU
Keyword(s):  
Iron Oxide ◽  
Short Range ◽  
Alkaline Earth ◽  
Structural Changes ◽  
Opposite Effect ◽  
Glass Stability ◽  
Intermediate Range Order ◽  
Alkaline Earths ◽  
Stability Effect

Glass stability and the structural role of iron oxide in x Fe 2 O 3(100-x)[ B 2 O 3– MO ] systems ( M=Ca , Sr or Ba , 0≤x≤30 mol%) were estimated from differential thermal analysis. The results suggest structural changes characteristic for the transition from short range to intermediate range order as the cationic field strength of the alkaline earths increases. In contrast, the iron addition has an opposite effect and determines a higher glass stability of these systems.

Two-component gas sensing with MIR dual comb spectroscopy

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Leonard Nitzsche ◽  
Jens Goldschmidt ◽  
Armin Lambrecht ◽  
Jürgen Wöllenstein
Keyword(s):  
Carbon Monoxide ◽  
Nitrous Oxide ◽  
Gas Sensing ◽  
Integration Time ◽  
Relative Precision ◽  
Acquisition Rate ◽  
Mid Infrared ◽  
Two Component ◽  
Absorption Features

Abstract A dual comb spectrometer is used as gas sensor for the parallel detection of nitrous oxide (N2O) and carbon monoxide (CO). These gases have overlapping absorption features in the mid-infrared (MIR) at a wavelength of 4.6 µm. With a spectra acquisition rate of 10 Hz, concentrations of 50 ppm N2O and 30 ppm CO are monitored with a relative precision of 6 × 10 − 3 6\times {10^{-3}} and 3 × 10 − 3 3\times {10^{-3}} respectively. The limit of detections are 91 ppb for N2O and 50 ppb for CO for an integration time of 25 s. The system exhibits a linear sensitivity from 2 ppm to 100 ppm with coefficients of determination of 0.99998 for N2O and 0.99996 for CO.

scholarly journals The alkaline earth halide spectra and their origin

1928 ◽  
Vol 118 (779) ◽  
pp. 120-137 ◽  
Keyword(s):  
Calcium Chloride ◽  
Alkali Metals ◽  
Alkaline Earth ◽  
Careful Study ◽  
Background Spectrum ◽  
Continuous Background ◽  
Alkaline Earths ◽  
The Subject ◽  
Band Spectra ◽  
Halogen Salts

It has been known since the early days of spectroscopy that there is a group of band spectra associated with the halogen salts of the alkaline earths. Probably the first distinction between the oxide and chloride bands of these elements was made by Lecoq de Boisbaudran when he observed relative intensity fluctuations between two band systems on introducing hydrochloric acid vapour into a flame charged with calcium chloride. The system intensified by the acid vapour he attributed to the chloride. The other halides were also found to yield characteristic spectra. Since their discovery they have been the subject of only one publication of any real note. Olmsted made a careful study of these spectra as they are found under flame excitation, and his catalogue of bands contains the only reliable data concerning these spectra which is available. An exception must be made of the fluoride spectra, which have been closely studied by Dufour, Datta, and others. The origin of the present investigation of these bands was the discovery that it is possible to observe them, very conveniently, in absorption against a continuous background spectrum. In the course of attempts to find band spectra of the alkaline earth metals (corresponding to those of the alkali metals) a pair of bands at about λ 6200 was observed in the absorption spectrum of a column of calcium vapour at temperatures of 900°C. and upwards. On measurement, these bands, which are reproduced in Plate 2, figs. 1, 2 and 5, were found to coincide with two prominent calcium chloride bands. Ordinary commercial calcium had been used for the experiments, and on analysis approximately 0·05 per cent, of chloride was found in it. It seemed evident that the development of the bands was due to this impurity in the metal, and the matter was clinched by adding a trace of bromide to the metal before heating, when the calcium bromide bands in the red also appeared prominently in absorption.

scholarly journals Soft interactions with hard Lewis acids: generation of mono- and dicationic alkaline-earth metal arene-complexes by direct oxidation

2020 ◽  
Vol 11 (8) ◽  
pp. 2068-2076 ◽  
Author(s):  
Marcel Schorpp ◽  
Ingo Krossing
Keyword(s):  
Lewis Acids ◽  
Alkaline Earth ◽  
Earth Metal ◽  
Alkaline Earth Metal ◽  
Arene Complexes ◽  
Direct Oxidation ◽  
Alkaline Earths ◽  
Soft Interactions

The alkaline earths like it hard and soft! By employing a radical cationic ligand-forming oxidising agent we gained access to unprecedented mono and dicationic arene complexes of calcium, strontium and barium.

Sign in / Sign up

Export Citation Format

Share Document