412results about "Tube vacuum systems" patented technology

A method and apparatus for focusing ions for delivery to an ion detection device using an aerodynamic ion focusing system that uses a high-velocity converging gas flow at an entrance aperture to focus an ion plume by reducing spreading and increasing desolvation of ions, and wherein a voltage is applied to at least a portion of the aerodynamic ion focusing system to assist in the focusing and delivery of ions to the ion detection device.

The invention relates to ions guided by gas flows in mass spectrometers, particularly in RF multipole systems, and to RF quadrupole mass filters and their operation with gas flows in tandem mass spectrometers. The invention provides a tandem mass spectrometer in which the RF quadrupole mass filter is operated at vacuum pressures in the medium vacuum pressure regime, utilizing a gas flow to drive the ions are through the mass filter. Vacuum pressures between 0.5 to 10 pascal are maintained in the mass filter. The mass filter may be enclosed by a narrow enclosure to guide the gas flow. The quadrupole mass filter may be followed by an RF multipole system, operated at the same vacuum pressure, serving as fragmentation cell to fragment the selected parent ions. The fragmentation cell may be enclosed by the same enclosure which already encloses the mass filter, so the ions may be driven by the same gas flow at the same vacuum pressure, greatly simplifying the required vacuum pumping system in tandem mass spectrometers. There are many other applications utilizing gas flows including supersonic gas jets in mass spectrometry.

A mass spectrometer includes an ion source and at least one vacuum stage, a means for delivering ions from the ion source to the vacuum stage, a collision cell, a detector, at least two multipole ion guide segments, and independent RF frequency and DC voltage sources applied to the multipole ion guide segments, the RF frequency and DC voltage sources being controlled independently of each other.

An ion transfer arrangement for transporting ions between higher and lower pressure regions of a mass spectrometer includes an electrode assembly (120) with a first plurality of ring electrodes (205) arranged in alternating relation with a second plurality of ring electrodes (210). The first plurality of ring electrodes (205) are narrower than the second plurality of ring electrodes (210) in a longitudinal direction, but the first plurality of ring electrodes have a relatively high magnitude voltage of a first polarity applied to them whereas the second plurality of ring electrodes (210) have a relatively lower magnitude voltage applied to them, of opposing polarity to that applied to the first set of ring electrodes (205). In this manner, ions passing through the ion transfer arrangement experience spatially alternating asymmetric electric fields that tend to focus ions away from the inner surface of the channel wall and towards the channel plane or axis of symmetry.

The present invention is for an improved ionization source chamber and ion beam delivery system which includes a vacuum chamber and flange arrangement, for mounting the means for transferring sample ions from the port to a mass analyzer and for mounting the ion production means, respectively. The flange containing the ion production means may be attached to the vacuum chamber via a hinge such that the flange can open as a door to provide easy access to the ion transfer electrodes in the vacuum chamber. Further, a variety of different ion production means may be mounted on the flange of the ionization source chamber of the present invention. As a result, any ion production means may be used with the present invention by substituting a flange which includes the desired ion production means.

The present invention is directed to a method and device to desorb an analyte using heat to allow desorption of the analyte molecules, where the desorbed analyte molecules are ionized with ambient temperature ionizing species. In various embodiments of the invention a current is passed through a mesh upon which the analyte molecules are present. The current heats the mesh and results in desorption of the analyte molecules which then interact with gas phase metastable neutral molecules or atoms to form analyte ions characteristic of the analyte molecules.

A miniature mass spectrometer that may be coupled to an atmospheric pressure ionisation source is described. Ions pass through a small orifice from a region at atmospheric pressure or low vacuum, and undergo efficient collisional cooling as they transit a very short, differentially pumped ion guide. A narrow beam of low energy ions is passed through a small aperture and into a separate chamber containing the mass analyser.

Methods for fragmenting ions in an ion trap are described. These methods involve a) selecting parent ions for fragmentation; b) retaining the parent ions within the ion trap for a retention time interval, the ion trap having an operating pressure of less than about 1×10-4 Torr; c) providing a RF trapping voltage to the ion trap to provide a Mathieu stability parameter q at an excitement level during an excitement time interval within the retention time interval; d) providing a resonant excitation voltage to the ion trap during the excitement time interval to excite and fragment the parent ions; e) providing a non-steady-state pressure increase of at least 10% of the operating pressure within the ion trap by delivering a neutral gas into the ion trap for at least a portion of the retention time interval to raise the pressure in the ion trap to a varying first elevated-pressure in the range between about 6×10-5 Torr to about 5×10-4 Torr for a first elevated-pressure duration; and f within the retention time interval and after the excitement time interval, terminating the resonant excitation voltage and changing the RF trapping voltage applied to the ion trap to reduce the Mathieu stability parameter q to a hold level less than the excitement level to retain fragments of the parent ions within the ion trap. The excitation time interval and the first elevated-pressure duration substantially overlap in time.

The present invention is directed to a method and device to desorb an analyte using heat to allow desorption of the analyte molecules, where the desorbed analyte molecules are ionized with ambient temperature ionizing species. In various embodiments of the invention a current is passed through a mesh upon which the analyte molecules are present. The current heats the mesh and results in desorption of the analyte molecules which then interact with gas phase metastable neutral molecules or atoms to form analyte ions characteristic of the analyte molecules.

A mass spectrometer system and a method of operating same are provided. The system comprises a) an ion conduit for receiving ions; b) a boundary member defining a curtain gas chamber containing the ion conduit; c) a curtain gas supply for providing a curtain gas directed by the boundary member to an inlet of the ion conduit to provide a gas flow into the ion conduit, and a curtain gas outflow out of a curtain gas chamber inlet; d) a mass spectrometer at least partially sealed to, and in fluid communication with, the ion conduit for receiving the ions from the ion conduit; a vacuum chamber surrounding the mass spectrometer operable to draw the gas flow including the ions through the ion conduit and into the vacuum chamber; and, e) a gas outlet for drawing a gas outflow from the gas flow located between the ion conduit and the mass spectrometer to increase the gas flow rate through the ion conduit.

A mass spectrometer is provided that is configurable for operation in both a Kinetic Energy Discrimination (KED) mode and a dynamic reaction cell (DRC) mode. To operate in the KED mode, a collision cell can be filled with a quantity of the inert gas, and an energy barrier can be formed between the collision cell and a downstream mass analyzer. To operate instead in the DRC mode, the collision cell can be filled with a quantity of gas that is reactive with the interferer ions.

The present invention relates to an apparatus and method for focusing, separating, and detecting gas-phase ions using the principles of electrohydrodynamic quadrupole fields at high pressures, at or near atmospheric pressure. Ions are entrained in a concentric flow of gas and travel through a high-transmission element into a RF / DC quadrupole, exiting out of the RF / DC quadrupole, and then impacting on an ion detector, such as a faraday plate; or through an aperture or capillary tube with subsequent identification by a mass spectrometer. Ions with stable trajectories pass through the RF / DC quadrupole while ions with unstable trajectories drift off-axis collide with the rods and are lost. Alternatively, detection of ions with unstable trajectories can be accomplished by allowing the ions to pass through the rods and be detected by an off-axis detector. Embodiments of this invention are devices and methods for focusing, separating, and detecting gas-phase ions at or near atmospheric pressure, when coupled to mass spectrometers.

An ion source is disclosed comprising a nebuliser 1 and a target 10. The nebuliser 1 is arranged and adapted to emit, in use, a stream of analyte droplets which are caused to impact upon the target 10 and to ionise analyte to form a plurality of analyte ions.

An ion funnel screen ions from a gas stream flowing into a differential pump stage of a mass spectrometer, transfers them to a subsequent differential pump stage. The ion funnel uses apertured diaphragms between which gas escapes easily. Holders for the apertured diaphragms are also provided that offer little resistance to the escaping gas while, at the same time, serving to feed the RF and DC voltages.

A mass spectrometer system includes a sample injection device defining a sample injection aperture. The system also includes an ion trap defining an ion outlet aperture. The ion trap is coupled to the sample injection device. The system further includes a detector positioned downstream of the ion outlet aperture. The system also includes an ion source coupled to the ion trap. The ion source is configured to ionize a sample injected into the ion trap and generate a plurality of ionized molecules within the ion trap. The ion trap is configured to maintain the plurality of ionized molecules therein while a plurality of neutral molecules migrate out of the ion trap until a predetermined pressure is attained in the ion trap.

A method of interfacing atmospheric pressure ion sources, including electrospray and desorption electrospray ionization sources, to mass spectrometers, for example miniature mass spectrometers, in which the ionized sample is discontinuously introduced into the mass spectrometer. Discontinuous introduction improves the match between the pumping capacity of the instrument and the volume of atmospheric pressure gas that contains the ionized sample. The reduced duty cycle of sample introduction is offset by operation of the mass spectrometer under higher performance conditions and by ion accumulation at atmospheric pressure.

The invention provides for a scanning electron or ion beam instrument capable of transferring the beam from a high vacuum chamber (8) into a high pressure chamber (5) via aperture (1) and aperture (2). The beam is deflected and scanned by coils (3) generally positioned between apertures (1) and (2). The amplitude of deflection of the beam over a specimen placed inside chamber (5) is substantially larger than the diameter of aperture (1). Leaking gas through aperture (1) is removed via port (7) by appropriate pumping apparatus. The size of aperture (1) is such that the pressure in chamber (6) combined with the supersonic jet and shock waves naturally forming therein do not result in catastrophic electron beam loss in chamber (6). The addition of appropriate detection means result in an instrument characterised by superior performance over prior art by way of better field of view at low magnification, better vacuum system and improved detection and imaging capabilities.

The systems and methods described herein include, among other things, systems capable of being deployed for long periods of time in oceanic, subsurface and atmospheric environments. The systems typically include mass spectrometers to measure low molecular weight gases dissolved in the water and volatile chemicals in air and water, and can move through the ocean, subsurface and atmospheric environment to take samples over a large geographic area. Additionally, these mass spectrometer devices are small and require little power and thereby facilitate the development of sample collection devices that can be placed at a remote location and operated for a substantial period of time from an on-board power supply such as a battery or a fuel cell. Such small and lightweight mass spectrometer devices when combined with low power AUVs (Autonomous Underwater Vehicles) and other manned and un-manned vehicles, can take samples over substantial distances and for a substantial period of time.

A mass spectrometer includes a plurality of guide stages for guiding ions between an ion source and an ion detector along a guide axis. Each of the guide stages is contained within one of a plurality of adjacent chambers. Pressure in each of the plurality of chambers is reduced downstream along the guide axis to guide ions along the axis. Each guide stage may further include a plurality of guide rods for producing a containment filed for containing ions about the guide axis, as they are guided to the detector.

A mass spectrometer of reduced size and weight is provided which is capable to conduct highly accurate mass spectroscopy. The mass spectrometer includes an ion source adapted to ionize gas flowing in from outside in order to ionize a measurement sample and a mass spectroscopy section for separating the ionized measurement sample. The ion source has its interior reduced in pressure by differential pumping from the mass spectroscopy section and ionizes the gas when the interior pressure rises as it inhales the gas, and the mass spectroscopy section separates the ionized measurement sample when its interior pressure falls after inhale of the gas. The mass spectrometer may further include a restriction device for suppressing a flow rate of the gas the ion source inhales and an open / close device for opening and closing a flow of the gas the ion source inhales.

A charged particle beam apparatus in which an electrostatic lens is used as a main focusing element to obtain a subminiature high-sensitivity high-resolution SEM, a drift tube for an electron beam is located inside a column between an electron source and a sample, and a detector for secondary electrons is located inside the drift tube. This solves the problem associated with the provision of a secondary electron detector, which heretofore has been a bottleneck in making a subminiature high-resolution SEM column.

A system for analyzing ions comprises: an ion source; a FAIMS cell comprising: (a) a gas inlet; (b) an outer electrode having a generally concave inner surface and comprising: (i) an ion inlet operable to receive the ions from the ion source and a carrier gas from the gas inlet; and (ii) an ion outlet; and (c) an inner electrode having a conduit therethrough and having a generally convex outer surface that is disposed in a spaced-apart and facing arrangement relative to the inner surface of the outer electrode for defining an ion separation region therebetween; and a mass analyzer for mass analyzing ions transmitted by the FAIMS cell through the ion outlet, wherein the inner electrode is moveable between a first position and a second position, the first position facilitating movement of the ions through the ion separation region, the second position facilitating movement of the ions through the conduit.

A mass spectrometer is provided that is configurable for operation in both a Kinetic Energy Discrimination (KED) mode and a dynamic reaction cell (DRC) mode. To operate in the KED mode, a collision cell can be filled with a quantity of the inert gas, and an energy barrier can be formed between the collision cell and a downstream mass analyzer. To operate instead in the mode, the collision cell can be filled with a quantity of gas that is reactive with the interferer ions.

The systems and methods described herein include, among other things, systems capable of being deployed for long periods of time in oceanic, subsurface and atmospheric environments. The systems typically include mass spectrometers to measure low molecular weight gases dissolved in the water and volatile chemicals in air and water, and can move through the ocean, subsurface and atmospheric environment to take samples over a large geographic area. Additionally, these mass spectrometer devices are small and require little power and thereby facilitate the development of sample collection devices that can be placed at a remote location and operated for a substantial period of time from an on-board power supply such as a battery or a fuel cell. Such small and lightweight mass spectrometer devices when combined with low power AUVs (Autonomous Underwater Vehicles) and other manned and un-manned vehicles, can take samples over substantial distances and for a substantial period of time.

A sealing surface, in particular for a vacuum chamber of a mass spectrometer and an associated manufacturing process, has non-circular shapes and can be produced with low effort. The sealing surface has circumferential cracks, being produced by erosion or jet machining or indentation-forming. A method manufactures such a sealing surface, a component has such a sealing surface, a vacuum chamber is made of components with such sealing surfaces and a mass spectrometer has such a vacuum chamber. In the prior art annular sealing surfaces are produced by turning. Milling permits a non-annular embodiment but is disadvantageous in case of sealing.

An ion source and method for providing ionized particles to a molecular / atomic analyser, such as a mass spectrometer, are disclosed. The ion source includes a vessel defining a channel; a gas inlet extending from the gas source into the channel, for introducing a gas flow into the channel; a sample inlet extending into the channel for introducing sample within the channel; and an ionizer to ionize the sample in the channel. The vessel is sufficiently sealed to allow the channel to be pressurized, at a pressure in excess of 100 Torr. At least one gas source maintains the pressure of the channel at a pressure in excess of 100 Torr and the pressure exterior to the channel at a pressure in excess of 0.1 Torr and provides a gas flow that sweeps across the ionizer to guide and entrain ions from the ionizer to the outlet.