WordNet

succeed in representing or expressing something intangible; "capture the essence of Spring"; "capture an idea"
a process whereby a star or planet holds an object in its gravitational field
any process in which an atomic or nuclear system acquires an additional particle
the act of forcibly dispossessing an owner of property (同)gaining control, seizure
the act of taking of a person by force (同)seizure
the removal of an opponents piece from the chess board
capture as if by hunting, snaring, or trapping; "I caught a rabbit in the trap today" (同)catch
attract; cause to be enamored; "She captured all the mens hearts" (同)enamour, trance, catch, becharm, enamor, captivate, beguile, charm, fascinate, bewitch, entrance, enchant
bring about the capture of an elementary particle or celestial body and causing it enter a new orbit; "This nucleus has captured the slow-moving neutrons"; "The star captured a comet"
discover or determine the existence, presence, or fact of; "She detected high levels of lead in her drinking water"; "We found traces of lead in the paint" (同)observe, find, discover, notice
rectifier that extracts modulation from a radio carrier wave (同)demodulator
any device that receives a signal or stimulus (as heat or pressure or light or motion etc.) and responds to it in a distinctive manner (同)sensor, sensing element
electronic equipment that detects the presence of radio signals or radioactivity
an elementary particle with negative charge (同)negatron

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〈動物・犯人・敵兵など〉'を'『捕える』,つかまえる / 〈物〉'を'手に入れる / 〈注意・関心など〉'を'ひきつける / 〈U〉(…を)『つかまえること』,(…の)捕獲,逗捕《+『of』+『名』》 / 〈C〉捕虜;捕獲した物(動物)
〈物事の存在〉‘を'『感知する』,気付く,認める / 〈人〉‘の'『正体を見破る』 / 〈電波〉‘を'検波する,復調する
発見者,探知者 / 探知器,検出器 / 検波器
『電子』,エレクトロン

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2013/06/08 16:49:32」(JST)

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Schematic of an electron capture detector for a gas chromatograph with a ⁶³Ni source.

An electron capture detector (ECD) is a device for detecting atoms and molecules in a gas through the attachment of electrons via electron capture ionization. The device was invented in 1957 by Dr. James E. Lovelock^[1]^[2] and is used in gas chromatography to detect trace amounts of chemical compounds in a sample.^[3]^[4]

Gas chromatograph detector [edit]

The electron capture detector is used for detecting electron-absorbing components (high electronegativity) such as halogenal compounds in the output stream of a gas chromatograph. The ECD uses a radioactive beta particle (electron) emitter in conjunction with a so-called makeup gas flowing through the detector chamber. The electron emitter typically consists of a metal foil holding 10 millicuries (370 MBq) of the radionuclide 63Ni. Usually, nitrogen is used as makeup gas, because it exhibits a low excitation energy, so it is easy to remove an electron from a nitrogen molecule. The electrons emitted from the electron emitter collide with the molecules of the makeup gas, resulting in many more free electrons. The electrons are accelerated towards a positively charged anode, generating a current. There is therefore always a background signal present in the chromatogram. As the sample is carried into the detector by the carrier gas, electron absorbing analyte molecules capture electrons and thereby reduce the current between the collector anode and a cathode. The analyte concentration is thus proportional to the degree of electron capture. ECD detectors are particularly sensitive to halogens, organometallic compounds, nitriles, or nitro compounds.

Sensitivity [edit]

Depending on the analyte, an ECD can be 10-1000 times more sensitive than a flame ionization detector (FID), and one million times more sensitive than a thermal conductivity detector (TCD). An ECD has a limited dynamic range and finds its greatest application in analysis of halogenated compounds.^[5] The detection limit for electron capture detectors is 5 femtograms per second (fg/s), and the detector commonly exhibits a 10,000-fold linear range. This made it possible to detect halogenated compounds such as pesticides and CFCs, even at levels of only one part per trillion (ppt), thus revolutionizing our understanding of the atmosphere and pollutants.

References [edit]

^ J. E. Lovelock (1958). "A sensitive detector for gas chromatography". Journal of Chromatography A 1 (1): 35–46. doi:10.1016/S0021-9673(00)93398-3.
^ J.E. Lovelock (1974). "The electron capture detector". Journal of Chromatography A 99 (1): 3–12. doi:10.1016/S0021-9673(00)90840-9.
^ M. Krejči and M. Dressler (1970). "Selective detectors in gas chromatography". Chromatographic Reviews 13 (1): 1–59. doi:10.1016/0009-5907(70)80005-9.
^ E. D. Pellizzari (1974). "Electron capture detection in gas chromatography". Journal of Chromatography A 98 (2): 323–361. doi:10.1016/S0021-9673(00)92077-6.
^ Various. "Advisory Opinion". Innovative Technology: Gas Chromatography Field Analysis. NEWMOA Technology Review Committee. Retrieved 2011-04-21.

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The use of copper(II) isonicotinate-based micro-solid-phase extraction for the analysis of polybrominated diphenyl ethers in soils.

Zhou YY, Zhang CY, Yan ZG, Li KJ, Wang L, Xie YB, Li FS, Liu Z, Yang J.SourceState Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China. Electronic address: zhouyy@craes.org.cn.
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Development and validation of an analytical method to determine fipronil and its degradation products in soil samples.

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PMID 22893178

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安武大輔,芦塚由紀,堀就英 [他]
福岡医学雑誌 102(4), 145-152, 2011-04-25
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NAID 40018966702

Effect of Light Intensity on the Photodegradation of PCB 153 in Aqueous Solution using UV and UV/H2O2

MACAWILE Maria Cristina,CENTENO Carmela,ABELLA Leonila,GALLARDO Susan,SUZUKI Masaaki
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… The decrease of the samples pH was a result of inorganic chlorides and acidic metabolites formation as measured using High Performance Liquid Chromatography (HPLC) - Conductivity Detector. … Likewise, the PCB concentration of irradiated samples was measured using Gas Chromatography equipped with Electron Capture Detector (GC-ECD). …
NAID 130000677434