Patent classifications
G01N27/68
Dielectric barrier discharge ionization detector
A dielectric barrier discharge ionization detector includes: a discharging section for generating plasma from argon-containing gas by electric discharge, including a dielectric tube on the outer wall of which a high-voltage electrode connected to AC power source as well as upstream-side and downstream-side ground electrodes and are circumferentially formed; and a charge-collecting section for ionizing sample-gas components by the plasma and detecting ion current formed by ionized components. The dielectric tube is made of a material whose resistivity is 1.010.sup.13 cm or lower. Furthermore, the detector satisfies at least one of the following conditions: the upstream-side ground electrode is longer than a ground electrode length which allows creeping discharge between the high-voltage electrode and a tube-line tip member; or the downstream-side ground electrode is longer than a ground electrode length which allows creeping discharge between the high-voltage electrode and the charge-collecting section.
Dielectric barrier discharge ionization detector
A dielectric barrier discharge ionization detector includes: a discharging section for generating plasma from argon-containing gas by electric discharge, including a dielectric tube on the outer wall of which a high-voltage electrode connected to AC power source as well as upstream-side and downstream-side ground electrodes and are circumferentially formed; and a charge-collecting section for ionizing sample-gas components by the plasma and detecting ion current formed by ionized components. The dielectric tube is made of a material whose resistivity is 1.010.sup.13 cm or lower. Furthermore, the detector satisfies at least one of the following conditions: the upstream-side ground electrode is longer than a ground electrode length which allows creeping discharge between the high-voltage electrode and a tube-line tip member; or the downstream-side ground electrode is longer than a ground electrode length which allows creeping discharge between the high-voltage electrode and the charge-collecting section.
Miniaturized pulsed discharge ionization detector, non-radioactive ionization sources, and methods thereof
The present application relates to pulsed discharge ionization detectors (PDIDs) and non-radioactive ionization sources, including miniaturized forms thereof. In some examples, the PDID includes annular electrodes, where each electrode is disposed between annular insulators. Also provided herein are methods of making and using such PDIDs, such as for detecting one or more volatile organic compounds, as well as non-radioactive ionization sources.
Dielectric barrier discharge ionization detector and method for tuning the same
To widen the dynamic range of a dielectric barrier ionization detector (BID), an insertion length of a sample injection tube 16 into a second gas passage 11 is set so that a sample-gas ejection port 16a is located on the downstream side of a dilution gas from the upper edge of a collector electrode 14 at which a DC electric field concentrates. By this setting, although the detection sensitivity is lower than in the case where the sample-gas ejection port 16a is placed to maximize the detection sensitivity, the decrease in the detection sensitivity to high-concentration samples is reduced since absorption of light by the sample gas is alleviated. Consequently, the sample-concentration range with a linearly-changing sensitivity becomes wider than that of conventional BIDs. Although the detection sensitivity becomes lower than that of conventional BIDs, a detection sensitivity adequately higher than that of FIDs can be ensured.
Dielectric barrier discharge ionization detector and method for tuning the same
To widen the dynamic range of a dielectric barrier ionization detector (BID), an insertion length of a sample injection tube 16 into a second gas passage 11 is set so that a sample-gas ejection port 16a is located on the downstream side of a dilution gas from the upper edge of a collector electrode 14 at which a DC electric field concentrates. By this setting, although the detection sensitivity is lower than in the case where the sample-gas ejection port 16a is placed to maximize the detection sensitivity, the decrease in the detection sensitivity to high-concentration samples is reduced since absorption of light by the sample gas is alleviated. Consequently, the sample-concentration range with a linearly-changing sensitivity becomes wider than that of conventional BIDs. Although the detection sensitivity becomes lower than that of conventional BIDs, a detection sensitivity adequately higher than that of FIDs can be ensured.
Analyzing Moisture Sensitive/Reactive Gases
Systems and methods for use in introducing samples to an analytical instrument. In particular, systems and methods to process moisture sensitive/reactive gases and then analyze by an analytical device/instrument using also a liquid calibrant sample. Suitable analytical devices include, for example, an inductively coupled plasma-mass spectrometer or inductively coupled plasma-optical emission spectrometer.
Analyzing Moisture Sensitive/Reactive Gases
Systems and methods for use in introducing samples to an analytical instrument. In particular, systems and methods to process moisture sensitive/reactive gases and then analyze by an analytical device/instrument using also a liquid calibrant sample. Suitable analytical devices include, for example, an inductively coupled plasma-mass spectrometer or inductively coupled plasma-optical emission spectrometer.
ION MOBILITY SPECTROMETER
A first shutter gate is disposed at an entrance of a drift region, and a second shutter gate is disposed on the downstream side in an ion-drifting direction. In a high-resolution measurement mode, a controller (9) controls voltage generators to open the second shutter gate to collect ions into a pulsed form at the first shutter gate. In this mode, the controller controls the voltage generators to open the first shutter gate to collect ions into a pulsed form at the second shutter gate. In a zoom-in measurement mode where ions within a specified range of ion mobility are measured with high resolving power, the controller controls the voltage generators to open the first shutter gate for a short period of time, and then to open the second shutter gate for a short period of time after a lapse of a predetermined time period.
ION MOBILITY SPECTROMETER
A first shutter gate is disposed at an entrance of a drift region, and a second shutter gate is disposed on the downstream side in an ion-drifting direction. In a high-resolution measurement mode, a controller (9) controls voltage generators to open the second shutter gate to collect ions into a pulsed form at the first shutter gate. In this mode, the controller controls the voltage generators to open the first shutter gate to collect ions into a pulsed form at the second shutter gate. In a zoom-in measurement mode where ions within a specified range of ion mobility are measured with high resolving power, the controller controls the voltage generators to open the first shutter gate for a short period of time, and then to open the second shutter gate for a short period of time after a lapse of a predetermined time period.
Nano discharges in liquids
The present invention is direct to a nano-probe corona tool and uses thereof. A nano-probe corona tool is disclosed having a tip with a diameter in the nano-scale, typically around 100 nm. The nano-probe corona tool is constructed of electrically conductive material. On the other end of the tool, a pulsed voltage source outputs a pulsed voltage to generate a pulsed electrical potential at the tip. The pulsed electrical potential at the tip causes a plasma discharge corona to occur. Uses of the corona discharge include, but are not limited to, optical emission spectroscopy, in the enhancement of deposition of coatings and nanoscale welding, e.g., nanotube or nanowires to a contact pad and welding two nanowires together, and in nanoscale surgery. For example, a nano-probe comprising CNTs may be inserted into cell membranes. The resulting corona discharge may be used to destroy tumors within the cell.