Argon-hydrogen

In a vacuum, uncoated molybdenum metal has an unlimited life at high temperatures. This is also tme under the vacuum-like conditions of outer space. Pure hydrogen, argon, and hehum atmospheres are completely inert to molybdenum at all temperatures, whereas water vapor, sulfur dioxide, and nitrous and nitric oxides have an oxidizing action at elevated temperatures. Molybdenum is relatively inert to carbon dioxide, ammonia, and nitrogen atmospheres up to about 1100°C a superficial nitride film may be formed at higher temperatures in the latter two gases. Hydrocarbons and carbon monoxide may carburize molybdenum at temperatures above 1100°C. 

This powerful drying agent is suitable for use with hydrogen, argon, helium, nitrogen, hydrocarbons, chlorinated hydrocarbons, esters and higher alcohols. 

Figure 6.7 Stripping voltammetry of saturated CO adlayers on Pt(l 11) cooled in a hydrogen-argon atmosphere (dashed line), leading to a well-defined smooth surface, and on Pt(lll) cooled in air (full line), leading to a less well-defined defect-rich surface sweep rate 50 mV/s.

Colorless gas with a repulsive, sickly sweet odor detectable at 1.8-3.5 ppm. Industrially, it can be found diluted with a variety of gases including hydrogen, argon, nitrogen, or helium. 

Common GC mobile phases (see Table 13.2) are hydrogen, argon, helium, nitrogen, and air. Helium and nitrogen are the most commonly used. Because gas chromatographic detectors are extremely sensitive and it is desirable to keep the noise level as low as possible, it is always advisable to use very high-purity gas as the mobile phase. 

The reducibility of the catalyst systems was further examined using temperature programmed reduction with a 3X hydrogen/argon gas mixture. The TPR curves shown in Figure 7 illustrate the NnP oxide catalyst is not readily reduced at reaction temperatures. In contrast, the FeNo oxide catalyst begins to reduce at 250 0, and the rate of reduction is fast at temperatures of methanol ammoxidation activity (425 -475°C). The poor lability of lattice oxygen for the HnP oxide catalyst provides additional evidence for a non-redox process. 

Jacquemin, J. et al.. Solubility of carbon dioxide, ethane, methane, oxygen, nitrogen, hydrogen, argon, and carbon monoxide in l-butyl-3-methylimidazolium tetrafluoroborate between temperatures 283 K and 343 K and at pressures close to atmospheric, /. Chem. Thermodyn., 38, 490, 2006. 

Fig. 3.18. Comparison of the D2-Ar ( ) and H2-Ar (x) rotational spectra at 165 K, and 142 and 150 amagat argon density for deuterium-argon and hydrogen-argon mixtures, repectively, and a hydrogen concentration of 2 to 10% after [109],...

Fig. 3.48. Enhancement of the absorption in the fundamental band in a hydrogen-argon mixture at low and high densities at 152 K the profiles are normalized to give Si(l) the same peak intensity. The argon density was 8 ama-gat (solid line) and 820 amagat (dashed line), respectively. The density splitting of the (overlap-induced) Q branch and the density narrowing of the S lines are apparent. A new (quadrupole-induced) Q line appears inthe wide absorption dip (between Qp and Qr) observed at high density. Reproduced with permission from the National Research Council of Canada from [137].

Fig. 3.51. Logarithmic plot of the normalized induced dipole moment correlation function, C(t), for hydrogen-argon mixtures at 165 K. Measurements at 90 amagat ( ) 450 amagat ( ) and 650 amagat (o). The broken lines at small times represents the portion of C(t) affected by the smoothing of the wings of the spectral profiles. Reproduced with permission by the National Research Council of Canada from [109].

Table 6.3. Various computed zeroth and first moments M , with and without lowest-order Wigner-Kirkwood quantum corrections, for a hydrogen-argon mixture at 195 K. Units are 10-34 J amagat-N for the zeroth moment, and 10-21 W amagat N for the first moments, with N = 2 and 3 for binary and ternary moments, respectively. An asterisk means that Wigner-Kirkwood corrections were not made for the entries of that line. The superscripts 12 and 122 stand for H2-Ar and H2-Ar-Ar, respectively [296].

Fig. 6.4.9. Brittleness of 0.6% MgO modified corundum sintered at 2073 K in environment hydrogen (/), argon (2), air (3), ammonia (4), nitrogen (5) and oxygen (6). (After Pavlushkin, 1961)...

The initiations achieved in the early work of Henderson (Ref 1) and Poole (Refs 2 3) with nitrogen iodide by a - particles, Kallmann and Schankler (Ref 9) with TNT, MF, NC, picrates and azides by intense beams of hydrogen, argon and mercury ions and also by electrons, and Muraour (Ref 10) with Ag acetylide by high speed electrons, brought forth the possible solution that the expins were caused by activation of a few neighboring molecules... 

Spectral line charts (hydrogen, argon, and neon) Demo 1.1 Stoppers 2.5 Styrofoam balls 1.1, 4.1 Sucrose 4.1... 

To demonstrate the viability of the synthesis and characterization approach in the present workflow, two binary Pt-Fe alloy libraries were designed, synthesized and characterized by XRD (Figs. 11.4 to 11.6) [19]. One library (Fig. 11.5) was characterized as synthesized, while the other (Fig. 11.6) was annealed at 400 °C for 12 h in a hydrogen/argon atmosphere. Pt-Fe is a well-known binary alloy system, exhibiting both substitutional solid solution compositional ranges and intermetal-lic compounds. 

Hansen, S.H., Larsen, E.H., Pritzi, G. and Cornett, C. (1992) Separation of seven arsenic compounds by high performance liquid chromatography with on-line detection by hydrogen-argon flame atomic absorption spectrometry and inductively coupled plasma mass spectrometry./. Anal. At. Spectrom., 1, 629-634. 

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