Abstract: The invention provides methods and devices to pulse ions from an RF ion storage into the flight tube of a time-of-flight mass spectrometer. The pusher cell comprises essentially two parallel plates, both plates completely slotted into two electrically insulated halves. The four half plates can be supplied with RF voltages to form a two-dimensional quadrupole field in the center between the slits, or with DC voltages to form a homogeneous acceleration field to eject ions. The RF quadrupole field is not ideal, but sufficiently good to store ions, to damp the ions by an additional collision gas, and to form a fine thread of ions in the axis of the quadrupole field. The DC acceleration field is extremely homogeneous; slight distortions near the slits can be corrected by external electrodes. The ideal acceleration field results in a high mass resolution and the device does not show any mass discrimination.

Abstract: The invention relates to the operation of trapping ion mobility spectrometers based on pushing ions by a gas flow against a counter-acting electric DC field barrier, preferably in combination with a mass analyzer as ion detector. The invention provides an additional RF ion trap upstream of the trapping ion mobility spectrometer, wherein the RF ion trap is operated as an accumulation unit in parallel with the trapping ion mobility spectrometer such that a first group of ions can be analyzed in the trapping ion mobility spectrometer while a second group of ions from an ion source are simultaneously collected in accumulation unit.

Abstract: In one aspect of the present invention, a method of fabricating a composite membrane includes: forming a first polymer solution from a first polymer and a second polymer solution from a second polymer, respectively, where the first polymer includes a charged polymer and the second polymer includes an uncharged polymer; electrospinning, separately and simultaneously, the first and second polymer solutions to form a dual fiber mat with first polymer fibers and second polymer fibers; and processing the dual fiber mat by softening and flowing one of the first or second polymer fibers to fill in the void space between the other of the first and second polymer fibers so as to form the composite membrane. In some embodiments, the composite membrane may be a proton exchange membrane (PEM) or an anion exchange membrane (AEM).

Abstract: The invention provides a trapping ion mobility analyzer and methods for operating the ion mobility analyzer. The trapping ion mobility analyzer comprises an RF field for radially confining ions along an axis, a region with an axial electric DC field and a gas flow along the axis counteracting the electric DC field in the region, wherein the region either comprises a rising edge with an increasing axial electric DC field or a falling edge with a decreasing axial electric DC field and wherein the slope of the electric field strength along the axis is not constant at a substantial portion of the edge.

Abstract: A cross-flow ion mobility spectrometer consists of two parallel plates defining a volume between them. Analyte ions flow along an axis from an entrance end to an exit end through the volume. An RF confining field tends to guide ions along the axis. An analytical gas flow is established orthogonal to the axis. A DC electrostatic analytical field is oriented in opposition to the analytical gas flow such that the “drag force” on ions of the selected mobility due to the analytical gas flow is balanced by the force on the ions due to the electrostatic analytical field. The selected ions are thereby able to follow a stable path to the exit end of the cross-flow mobility analyzer. However, the force on ions of other than the selected mobility is unbalanced and these ions are deflected and lost.

Abstract: Ions with a predetermined range of ion mobilities are produced by filtering input ions with at least two consecutive ion mobility high pass and/or low pass filters. Each ion mobility filter is formed by entraining ions in a moving gas and applying a DC electric field to the ions which causes the ions to move in a direction opposite to the gas flow. An ion mobility high pass filter is formed when the DC electric field drives the ions against the flow of gas, whereas an ion mobility low pass filter is formed when a the gas flow drives entrained ions against an DC electric field barrier.

Abstract: An improved trap-TOF mass spectrometer has a set of electrodes arranged to produce both a quadrupolar RF confining field and a substantially homogeneous dipole field. In operation, ions are first confined by the RF field and then, at a selected time, the RF confining field is discontinued and the dipole field is used to accelerate the ions so as to initiate a TOF MS analysis. The apparatus of the present invention may be used alone or in conjunction with other analyzers to produce mass spectra from analyte ions.

Abstract: The invention provides methods and devices to pulse ions from an RF ion storage into the flight tube of a time-of-flight mass spectrometer. The pusher cell comprises essentially two parallel plates, both plates completely slotted into two electrically insulated halves. The four half plates can be supplied with RF voltages to form a two-dimensional quadrupole field in the center between the slits, or with DC voltages to form a homogeneous acceleration field to eject ions. The RF quadrupole field is not ideal, but sufficiently good to store ions, to damp the ions by an additional collision gas, and to form a fine thread of ions in the axis of the quadrupole field. The DC acceleration field is extremely homogeneous; slight distortions near the slits can be corrected by external electrodes. The ideal acceleration field results in a high mass resolution and the device does not show any mass discrimination.

Abstract: A method of providing changes in healthcare policy information is provided, including: providing a first database, the first database containing a plurality of records, each record containing a copy of a website and tags associated with the website, the website pertaining to healthcare policy information; retrieving current versions of tags associated with the websites on the Internet; for each website, determining if the tags associated with the website have changed by comparing the current version of the tags to the copy of the tags in the first database; if the tags have changed, updating the copy of the website associated with the tags in the first database; determining the changes in the website, and providing access to reports generated to reflect changes in the website.

Abstract: An abridged multipole structure for the transport and selection of ions along a central axis in a vacuum system is constructed from a plurality of rectilinear electrode structures, each having a substantially planar face with a first dimension and a second dimension perpendicular to the first dimension. When a voltage is applied across the second dimension, an electrical potential is produced at the planar face whose amplitude is a linear function of position along the second dimension. Two electrode structures can be arranged parallel to each other with the first dimension extending along the central axis or more electrodes structures can be arranged to form multipole structures with various polygonal cross sections. Additional embodiments can act as linear ion traps or Paul ion traps.

Abstract: An abridged multipole structure for the transport and selection of ions along a central axis in a vacuum system is constructed from a plurality of rectilinear electrode structures, each having a substantially planar face with a first dimension and a second dimension perpendicular to the first dimension. When a voltage is applied across the second dimension, an electrical potential is produced at the planar face whose amplitude is a linear function of position along the second dimension. Two electrode structures can be arranged parallel to each other with the first dimension extending along the central axis or more electrodes structures can be arranged to form multipole structures with various polygonal cross sections.

Abstract: Ions with a predetermined range of ion mobilities are produced by filtering input ions with at least two consecutive ion mobility high pass and/or low pass filters. Each ion mobility filter is formed by entraining ions in a moving gas and applying a DC electric field to the ions which causes the ions to move in a direction opposite to the gas flow. An ion mobility high pass filter is formed when the DC electric field drives the ions against the flow of gas, whereas an ion mobility low pass filter is formed when a the gas flow drives entrained ions against an DC electric field barrier.

Abstract: An improved trap-TOF mass spectrometer has a set of electrodes arranged to produce both a quadrupolar RF confining field and a substantially homogeneous dipole field. In operation, ions are first confined by the RF field and then, at a selected time, the RF confining field is discontinued and the dipole field is used to accelerate the ions so as to initiate a TOF MS analysis. The apparatus of the present invention may be used alone or in conjunction with other analyzers to produce mass spectra from analyte ions.

Abstract: Ions with a predetermined ion mobility range are produced by filtering ions entrained in a stream of moving gas with two ion mobility low pass filters located consecutively in the gas stream. Each filter is formed by applying a DC electric field to the gas stream which causes the ions to move in a direction opposite to the gas flow. Ions are collected between the two filters and transferred to a detector or analyzing device. In one embodiment, the maximum field strength of the electric field barrier in the first ion mobility low pass filter is continued as a plateau of essentially constant field strength up to the electric field barrier in the second ion mobility low pass filter, which has a maximum field strength higher that the maximum field strength of the electric field barrier in the first ion mobility low pass filter.

Abstract: Ions with a predetermined range of ion mobilities are produced by filtering input ions with at least two consecutive ion mobility high pass and/or low pass filters. Each ion mobility filter is formed by entraining ions in a moving gas and applying a DC electric field to the ions which causes the ions to move in a direction opposite to the gas flow. An ion mobility high pass filter is formed when the DC electric field drives the ions against the flow of gas, whereas an ion mobility low pass filter is formed when a the gas flow drives entrained ions against an DC electric field barrier.

Abstract: An abridged multipole structure for the transport and selection of ions along a central axis in a vacuum system is constructed from a plurality of rectilinear electrode structures, each having a substantially planar face with a first dimension and a second dimension perpendicular to the first dimension. When a voltage is applied across the second dimension, an electrical potential is produced at the planar face whose amplitude is a linear function of position along the second dimension. Two electrode structures can be arranged parallel to each other with the first dimension extending along the central axis or more electrodes structures can be arranged to form multipole structures with various polygonal cross sections. Additional embodiments can act as linear ion traps or Paul ion traps.

Abstract: A cross-flow ion mobility spectrometer consists of two parallel plates defining a volume between them. Analyte ions flow along an axis from an entrance end to an exit end through the volume. An RF confining field tends to guide ions along the axis. An analytical gas flow is established orthogonal to the axis. A DC electrostatic analytical field is oriented in opposition to the analytical gas flow such that the “drag force” on ions of the selected mobility due to the analytical gas flow is balanced by the force on the ions due to the electrostatic analytical field. The selected ions are thereby able to follow a stable path to the exit end of the cross-flow mobility analyzer. However, the force on ions of other than the selected mobility is unbalanced and these ions are deflected and lost.

Abstract: In one aspect of the present invention, a method of fabricating a composite membrane includes: forming a first polymer solution from a first polymer and a second polymer solution from a second polymer, respectively, where the first polymer includes a charged polymer and the second polymer includes an uncharged polymer; electrospinning, separately and simultaneously, the first and second polymer solutions to form a dual fiber mat with first polymer fibers and second polymer fibers; and processing the dual fiber mat by softening and flowing one of the first or second polymer fibers to fill in the void space between the other of the first and second polymer fibers so as to form the composite membrane. In some embodiments, the composite membrane may be a proton exchange membrane (PEM) or an anion exchange membrane (AEM).

Abstract: A method of providing changes in healthcare policy information is provided, including: maintaining a first database, the first database containing records including copies of websites, the websites pertaining to policy information; a first server scanning current versions of the websites on the Internet and identifying which of the websites have been changed to a second server; and updating the records in the first database; a second server generating a report of the changes made to each of the identified websites; and the second server providing access to a user to generate reports relating to the websites.

Abstract: A cross-flow ion mobility spectrometer consists of two parallel plates defining a volume between them. Analyte ions flow along an axis from an entrance end to an exit end through the volume. An RF confining field tends to guide ions along the axis. An analytical gas flow is established orthogonal to the axis. A DC electrostatic analytical field is oriented in opposition to the analytical gas flow such that the “drag force” on ions of the selected mobility due to the analytical gas flow is balanced by the force on the ions due to the electrostatic analytical field. The selected ions are thereby able to follow a stable path to the exit end of the cross-flow mobility analyzer. However, the force on ions of other than the selected mobility is unbalanced and these ions are deflected and lost.