Raman spectroscopy is also used in combustion diagnostics. Being a completely non-intrusive technique, it permits the detection of the major species and temperature distribution inside combustors and in flames without any perturbation of the (mainly fluid dynamic and reactive) processes examined. 圖片參考:http://upload.wikimedia.org/wikipedia/en/8/87/Rama... Raman spectroscopy is commonly used in chemistry, since vibrational information is very specific for the chemical bonds in molecules. It therefore provides a fingerprint by which the molecule can be identified. The fingerprint region of organic molecules is in the range 500-2000 cm-1. Another way that the technique is used is to study changes in chemical bonding, e.g. when a substrate is added to an enzyme.An important advantage of Raman spectra over infrared lies in the fact that water does not cause interference; indeed, Raman spectra can be obtained form aqueous solutions. In addition, glass or quartz cells can be employed, thus avoiding the inconvenience of working with sodium chloride or other atmospherically unstable confinements. Thus aqueous solutions can be studied by Raman spectroscopy but not by IR. This advantage is particularly important for biological and inorganic systems and in studies dealing with water pollution problems. Despite these advantages, Raman spectroscopy is subject to interference by fluorescence or impurities in the sample.Rosen used Raman spectroscopy to unambiguously demonstrate that BC is composed of graphitic-like carbon. Rosen put together a simple device that measured the absorption of light by black carbon deposited on a filter with air passing through it."I deduced that the rate at which the filter became black with carbon was proportional to the amount of carbon in the air," says Hansen. This suggested that a real-time measurement device was possible.
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圖片參考:http://upload.wikimedia.org/wikipedia/en/8/87/Rama...
Raman spectroscopy is commonly used in chemistry, since vibrational information is very specific for the chemical bonds in molecules. It therefore provides a fingerprint by which the molecule can be identified. The fingerprint region of organic molecules is in the range 500-2000 cm-1. Another way that the technique is used is to study changes in chemical bonding, e.g. when a substrate is added to an enzyme.An important advantage of Raman spectra over infrared lies in the fact that water does not cause interference; indeed, Raman spectra can be obtained form aqueous solutions. In addition, glass or quartz cells can be employed, thus avoiding the inconvenience of working with sodium chloride or other atmospherically unstable confinements. Thus aqueous solutions can be studied by Raman spectroscopy but not by IR. This advantage is particularly important for biological and inorganic systems and in studies dealing with water pollution problems. Despite these advantages, Raman spectroscopy is subject to interference by fluorescence or impurities in the sample.Rosen used Raman spectroscopy to unambiguously demonstrate that BC is composed of graphitic-like carbon. Rosen put together a simple device that measured the absorption of light by black carbon deposited on a filter with air passing through it."I deduced that the rate at which the filter became black with carbon was proportional to the amount of carbon in the air," says Hansen. This suggested that a real-time measurement device was possible.