• Mixtures
  • In practice, it is often not practical to achieve a completely O2- or water-free conditions, especially as pyrolysis is often conducted on complex mixtures. (wikipedia.org)
  • The term "tholin" was coined by astronomer Carl Sagan and his colleague Bishun Khare to describe the difficult-to-characterize substances they obtained in his Miller-Urey-type experiments on the methane-containing gas mixtures such as those found in Titan's atmosphere. (wikipedia.org)
  • Their paper proposing the name "tholin" said: For the past decade we have been producing in our laboratory a variety of complex organic solids from mixtures of the cosmically abundant gases CH 4, C 2H 6, NH 3, H 2O, HCHO, and H 2S. (wikipedia.org)
  • molecules
  • The molecules are retained by the column and then elute (come off) from the column at different times (called the retention time), and this allows the mass spectrometer downstream to capture, ionize, accelerate, deflect, and detect the ionized molecules separately. (wikipedia.org)
  • Sometimes two different molecules can also have a similar pattern of ionized fragments in a mass spectrometer (mass spectrum). (wikipedia.org)
  • Combining the two processes reduces the possibility of error, as it is extremely unlikely that two different molecules will behave in the same way in both a gas chromatograph and a mass spectrometer. (wikipedia.org)
  • Advances are continually improving the technical performance of chromatography, allowing the separation of increasingly similar molecules. (wikipedia.org)
  • spectrometer
  • The first on-line coupling of gas chromatography to a mass spectrometer was reported in 1959. (wikipedia.org)
  • In 1964, Electronic Associates, Inc. (EAI), a leading U.S. supplier of analog computers, began development of a computer controlled quadrupole mass spectrometer under the direction of Robert E. Finnigan. (wikipedia.org)
  • The GC-MS is composed of two major building blocks: the gas chromatograph and the mass spectrometer. (wikipedia.org)
  • Plotted on the x-axis is the retention time and plotted on the y-axis a signal (for example obtained by a spectrophotometer, mass spectrometer or a variety of other detectors) corresponding to the response created by the analytes exiting the system. (wikipedia.org)
  • The mass spectrometer (MS) and the main electronics of MOMA are provided by NASA's Goddard Space Flight Center, while the gas chromatography (GC) is provided by the two French institutes LISA and LATMOS. (wikipedia.org)
  • combine
  • The original vascular structure of the wood and the pores created by escaping gases combine to produce a light and porous material. (wikipedia.org)
  • exposure
  • Most of the toxicological data on gas exposure is based on the 8-hour work period of the terrestrial worker and is therefore unsuitable for spacecraft work. (wikipedia.org)
  • liquid
  • Besides the usage of dedicated pyrolyzers, pyrolysis GC of solid and liquid samples can be performed directly inside programmable temperature vaporizer (PTV) injectors that provide quick heating (up to 60 °C/s) and high maximum temperatures of 600-650 °C. This is sufficient for many pyrolysis applications. (wikipedia.org)
  • method
  • Hi, I'm Tom Wheat, Principal Scientist at Waters, and I recently hosted a webinar entitled, "Developing, Testing and Troubleshooting Chromatography Method Transfer. (environmental-expert.com)
  • Chromatography is a physical method of separation that distributes components to separate between two phases, one stationary (stationary phase), the other (the mobile phase) moving in a definite direction. (wikipedia.org)
  • substances
  • Aspirational applications of pyrolysis would convert biomass into syngas and biochar, waste plastics back into usable oil, or waste into safely disposable substances. (wikipedia.org)
  • molecular
  • Size-exclusion chromatography (SEC) and Py-GC-MS were used to measure molecular weights and average chemical compositions, respectively. (uva.nl)
  • technique
  • New types of chromatography developed during the 1930s and 1940s made the technique useful for many separation processes. (wikipedia.org)
  • Chromatography technique developed substantially as a result of the work of Archer John Porter Martin and Richard Laurence Millington Synge during the 1940s and 1950s, for which they won the 1952 Nobel Prize in Chemistry. (wikipedia.org)
  • processes
  • Pyrolysis differs from other processes like combustion and hydrolysis in that it usually does not involve the addition of other reagents such as oxygen (O2, in combustion) or water (in hydrolysis). (wikipedia.org)
  • surface
  • Toxic gases are produced as an off-gassing from the astronauts and non-metallic materials e.g. surface coatings, adhesives, elastomers, solvents, cleaning agents, heat exchanger liquids etc. (wikipedia.org)
  • coal
  • High temperature pyrolysis is used on a industrial scale to convert coal into coke for metallurgy, especially steelmaking. (wikipedia.org)
  • primarily
  • He continued to work with chromatography in the first decade of the 20th century, primarily for the separation of plant pigments such as chlorophyll, carotenes, and xanthophylls. (wikipedia.org)
  • water
  • The term has also been applied to the decomposition of organic material in the presence of superheated water or steam (hydrous pyrolysis), for example, in the steam cracking of oil. (wikipedia.org)