公开(公告)号：EP1002230A1

公开(公告)日：2000-05-24

申请号：EP98937671.0

申请日：1998-08-05

申请人： The Secretary of State for Defence

发明人： JONES, Christopher, David

IPC分类号： G01N27/66

CPC分类号： G01N27/66 ,  G01N33/0022 ,  G01N33/0031

摘要： A gas detection device for distinguishing at a single point, two simultaneously emitted gases and, and in particular, for measuring the individual concentration of each gas at the point, comprising two flow passages into which a sample comprising the two gases is input, gas induction means for drawing the sample into and through the flow passages and means for irradiating each of the flow passages with ultraviolet radiation of a different energy. The device may comprise two sources of ultraviolet radiation, wherein each of the sources (e.g. a krypton and an argon lamp) emits radiation into one of the flow passages. Upon irradiation of the gases (e.g. propane and propylene) within the sample the gases are ionised, one of them being ionised by radiation in one of the flow passages and the other being ionised by radiation in both of the flow passages. Each flow passage has an associated bias electrode, and a collector electrode which are arranged downstream of the irradiated flow passages. The currents at the collector electrodes give an indication of the ionised gas (or gases) in each flow passage. The invention also relates to a method of measuring, at a single point, the individual concentrations of two simultaneously emitted gases. This measurement may be used in the development of models and other tools for determining, for example, gas hazard or nuisance. The device and method have particular application in environmental pollution monitoring, atmospheric tracer gas detection and in the monitoring of gas or vapour emitting processes.

公开(公告)号：EP0595929A1

公开(公告)日：1994-05-11

申请号：EP92915935.0

申请日：1992-07-17

申请人： THE SECRETARY OF STATE FOR DEFENCE IN HER BRITANNIC MAJESTY'S GOVERMENT OF THE UNITED KINGDOM OF GREAT BRITAIN AND

发明人： JONES, Christopher, David

IPC分类号： G01N27 ,  G01N33 ,  H01J41

CPC分类号： G01N27/66 ,  G01N33/0011 ,  H01J41/02

摘要： Procédé et dispositif améliorés de détection de vapeur ou de gaz ionisable qui peuvent dans des formes d'exécution préférées échantillonner au moins 4 x 10-3 mètres cubes d'air par sec-1 et qui réagissent aux fluctuations du gaz ionisable à une vitesse inférieure ou égale à 100 Hz. On a découvert que l'utilisation du dispositif de cette invention conférait une sensibilité à la vapeur ou au gaz ionisable par les ultra-violets dépassant 500 fois celle des dispositifs de l'état antérieur de la technique et permettait de détecter un gaz traceur de propylène à des concentrations de 2 parties pour 1.000.000.000 augmentant par conséquent l'éloignement de la source de gaz avec lequel on peut utiliser le dispositif de manière fiable. Cette invention concerne également l'utilisation de ce dispositif pour détecter des fuites de composés volatiles pouvant être ionisés par les UV et pour surveiller des processus dans lesquels des vapeurs sont émises.

公开(公告)号：EP0752196A1

公开(公告)日：1997-01-08

申请号：EP95911435.0

申请日：1995-03-20

申请人： THE SECRETARY OF STATE FOR DEFENCE

发明人： JONES, Christopher, David ,  GRIFFITHS, Richard, Frederick Environmental Techn.

IPC分类号： G01N27 ,  H05B41

CPC分类号： H05B41/382 ,  G01N27/66 ,  H05B41/16 ,  H05B41/24

摘要： An ultra-violet lamp (19) has a pair of electrodes (31, 32) within the lamp, the electrodes being connected to a DC power supply (34). There is a coil (37) wound round the lamp, the coil being connected to an RF power supply (38). The DC power supply (34) and the RF power supply (38) are controlled by control means (39) adapted to activate an RF voltage in the coil (37) to initiate the supply of ultra-violet light (20) from the lamp, to activate a DC voltage between the electrodes (31, 32), and to switch off the RF voltage when the DC voltage is sufficient to maintain the supply of ultra-violet light.

公开(公告)号：EP0687359A1

公开(公告)日：1995-12-20

申请号：EP94908414.0

申请日：1994-03-03

申请人： THE SECRETARY OF STATE FOR DEFENCE IN HER BRITANNIC MAJESTY'S GOVERNMENT OF THE UNITED KINGDOM OF GREAT BRITAIN AND

发明人： GRIFFITHS, Richard, Frederick 9 Crampton Drive ,  JONES, Christopher, David

IPC分类号： G01N27

CPC分类号： G01N27/66

摘要： Gas detector includes structure (10) defining a gas flow passage (11), means (12) for passing an ultraviolet light beam (13) across the passage, and first and second electrodes (16, 17) downstream of the ultraviolet light means (12), at least one of the first and second electrodes (16, 17) being in the form of a series of electrically separate segments (16a, 17a) extending in a downstream direction, the electrodes (16, 17) being connectable to potential applying means (18) and to means (20) whereby the current passing through each segment (16a, 17a) of a segmented electrode (16, 17) can be measured.