Microwave detection of interstellar formaldehyde.
Interstellar formaldehyde detection in absorption against galactic and extragalactic radio sources, discussing chemical evolution
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Interstellar formaldehyde detection in absorption against galactic and extragalactic radio sources, discussing chemical evolution
Molecular collision pumping mechanism for anomalous microwave absorption by formaldehyde rotational transition in Galaxy dust cloud
One man formaldehyde synthesis system
Microwave absorption by rotational transition of interstellar formaldehyde in direction of Sgr B2, Sgr A and W51
Polymer structure and cross-link density effects on thermal analysis of phenol-formaldehyde polymers pyrolysis products
Rotational transition of interstellar formaldehyde in absorption in direction of galactic and extragalactic objects
Formose sugars production from formaldehyde, discussing economic conversion by catalytic reactions
Formaldehyde rotational transition hyperfine components measured by molecular beam maser
Formaldehyde absorption coefficients measured photoelectrically in vacuum UV range
Amino acids synthesis by formaldehyde-ammonia heating and hydrolysis, simulating reactants in weakly reducing atmosphere at volcanic temperatures
Adsorbed formaldehyde levels from vaporized paraformaldehyde on various surfaces as function of relative humidity and chemical concentration
Formaldehyde line emission observed from trapezium H II region of Orion nebula, attributing to 140 GHz rotational transition
Formaldehyde vapor photodecomposition modes by end product analysis, utilizing mixed isotope, radical scavenger, inert gas pressurization and lamp intensity attenuation
Formaldehyde absorption and emission lines in Orion IR nebula, indicating pumping suppression by neutral particle collisions
Formaldehyde transitions in ground and excited states at 6 cm, attaining line widths and hyperfine structure at 1-3 kHz
Investigation of the quantum mechanics of the collisional pumping process which Townes and Cheung (1969) propose as the cause of 'anomalous' formaldehyde absorption in diffuse dark nebulae discussed by Palmer et al. (1969). Quantum effects are taken into account in an attempt to determine whether such nebulae are likely to provide the physical conditions required for the collisional pumping process.
Beam-maser spectrometric measurements to an accuracy of about 100 Hz have been conducted of the 2(11)-2(12) transition for the isotopic species of greatest astronomical interest - i.e., H2CO, H2(13)CO, and H2C(18)O. The samples used were not isotopically enriched, monomeric formaldehyde vapors. For these species, all the coupling constants required to calculate the hyperfine structure of any rotational transition have been determined.
Device makes use of microwave spectral absorption in low-Q resonant Stark cell, and indications are that ultimate sensitivity of instrument is within 100 parts per billion of formaldehyde. Microwave source is very small and requires only six-volt dc bias for operation. Coarse tuning is accomplished mechanically and fine tuning by adjusting dc-bias voltage.