ROY PETER MOELLER
Pilots at Warwick Ave, San Leandro, CA
License number
California A1314397
Category
Airmen
Type
Authorized Aircraft Instructor
Address
Address
586 Warwick Ave, San Leandro, CA 94577
Professional information
Stabilized Electron Multiplier Anode
US Patent:
8637811, Jan 28, 2014
Filed:
Jul 15, 2011
Appl. No.:
13/184022
Inventors:
Urs Steiner - Branford CT, US
Roy P Moeller - San Leandro CA, US
David Deford - Pleasanton CA, US
Roy P Moeller - San Leandro CA, US
David Deford - Pleasanton CA, US
Assignee:
Bruker Daltonics, Inc. - Billerica MA
International Classification:
B01D 59/44
US Classification:
250283, 313103 R
Abstract:
Methods and systems to compensate for distortions created by dynamic voltage applied to an electron multiplier used in mass spectrometry. An electron multiplier has a cathode end accepting ion flow, an opposite emitter end and an interior surface. The electron multiplier produces an electron output from ions colliding with the interior surface. A variable power supply has a voltage output coupled to the cathode end and the emitter end of the electron multiplier. The voltage output changes dynamically to adjust the electron output from the electron multiplier. An anode is located in proximity to the electron multiplier. An electrometer is coupled to the anode in proximity to the electron multiplier to measure the current generated by the electron output. A low pass filter circuit is coupled to the emitter end to the ground of the electrometer to attenuate emitter voltage changes. A bias circuit is coupled to the emitter end to stabilize emitter to anode voltage difference.
Atmospheric Pressure Ion Source With Exhaust System
US Patent:
2014006, Mar 6, 2014
Filed:
Sep 3, 2012
Appl. No.:
13/602249
Inventors:
Zicheng YANG - Alameda CA, US
Roy P. MOELLER - San Leandro CA, US
Stephen ZANON - Campbell CA, US
Roy P. MOELLER - San Leandro CA, US
Stephen ZANON - Campbell CA, US
Assignee:
BRUKER DALTONICS, INC. - Billerica MA
International Classification:
H01J 27/02, H01J 27/24
US Classification:
250424, 250423 R, 250423 P
Abstract:
An atmospheric pressure ion source, employing the principle of electrospray ionization, chemical ionization, or photo-ionization, comprises a spray probe for spraying a liquid into an ionization chamber and has an exhaust port through which residual spray mist and waste gas, such as evaporated solvent, are extracted. The ion source further comprises an exhaust system comprising a conduit which is connected to the exhaust port. The conduit has a transition from a first cross-section to a second cross section at a point downstream of the exhaust port wherein the second cross section is reduced in relation to the first cross section. Gas is injected via a gas injector into the conduit in a region of the transition to create a low pressure region that removes unwanted material from the chamber.
Method For Controlling Space Charge-Driven Ion Instabilities In Electron Impact Ion Sources
US Patent:
7291845, Nov 6, 2007
Filed:
Apr 26, 2005
Appl. No.:
11/114481
Inventors:
Roy Moeller - San Leandro CA, US
Felician Muntean - Danville CA, US
Urs Steiner - Sunnyvale CA, US
Felician Muntean - Danville CA, US
Urs Steiner - Sunnyvale CA, US
Assignee:
Varian, Inc. - Palo Alto CA
International Classification:
H01J 27/00
US Classification:
250427, 250423 R
Abstract:
In a method for inhibiting space charge-related effects in an ion source, an electron beam is directed into a chamber to produce ions from sample material in the chamber. A voltage pulse is applied to the chamber to perturb an electron space charge present in the chamber. The ion source may be an electron impact ionization (EI) apparatus. The ion source may operated in conjunction with a mass spectrometry system.
Lens Free Collision Cell With Improved Efficiency
US Patent:
8481929, Jul 9, 2013
Filed:
Feb 28, 2012
Appl. No.:
13/406767
Inventors:
Urs Steiner - Branford CT, US
Felician Muntean - Danville CA, US
Roy P Moeller - San Leandro CA, US
Thinh M Ha - San Jose CA, US
Felician Muntean - Danville CA, US
Roy P Moeller - San Leandro CA, US
Thinh M Ha - San Jose CA, US
Assignee:
Bruker Daltonics, Inc. - Billerica MA
International Classification:
H01J 49/06, G01N 27/00, H01J 49/00, G01N 27/62
US Classification:
250292, 250281, 250282, 250284, 250286, 250288, 250290, 250291, 250294
Abstract:
An ion collision cell is fabricated by four semi-circular profile elements, all of which are attach to the same reference plate. Consequently, all four elements remain aligned to the same reference plate. The four elements form a semi-circular channel with a semi-circular quad electrodes. The quad electrodes receive electrical potential to form the field required to focus and maintain the ions at the center of the channel. semi-circular insulators are provided on all sides of the channel so as to seal the channel over its length from the interior of the mass spectrometer.
System And Method To Eliminate Radio Frequency Coupling Between Components In Mass Spectrometers
US Patent:
8314385, Nov 20, 2012
Filed:
Apr 19, 2011
Appl. No.:
13/089980
Inventors:
Roy Moeller - San Leandro CA, US
Assignee:
Bruker Daltonics, Inc. - Billerica MA
International Classification:
H01J 49/42, H01J 49/40, H01J 49/26
US Classification:
250293, 250290
Abstract:
A radio frequency component for use in a mass spectrometer is described. The radio frequency component includes a plurality of electrodes. The plurality of electrodes is configured around a central axis to create an ion channel within the plurality of electrodes. In addition, each of the plurality of electrodes is paired with an opposing electrode across the central axis. And, at least one electrode pair has an electrode extension on each electrode. The electrode extension is configured to overlap at least a portion of a proximate electrode of a second radio frequency component.
Multipole Assembly And Method For Its Fabrication
US Patent:
8492713, Jul 23, 2013
Filed:
Feb 28, 2012
Appl. No.:
13/406651
Inventors:
Urs Steiner - Branford CT, US
Roy P Moeller - San Leandro CA, US
Stephen Zanon - Campbell CA, US
Roy P Moeller - San Leandro CA, US
Stephen Zanon - Campbell CA, US
Assignee:
Bruker Daltonics, Inc. - Billerica MA
International Classification:
H01J 49/42, H01J 49/34, H01J 49/06
US Classification:
250290, 250281, 250282, 250288, 250291, 250396 R, 156 60, 156153, 156250, 156305, 156 736
Abstract:
A multipole rod assembly, such as used as mass analyzer, is fabricated using rods adhesively attached to shoes, which are then attached to isolation rings. A fixture is used in conjunction with precision-made spacers to precisely assemble the ion mass analyzer. The rods and shoes can be made of metal, while the isolation rings are preferably made of insulator, such as ceramic. The shoes and isolation rings need not be made to high precision, as the spacer ensures high accuracy in alignment and symmetry of the rods. Consequently, the rods are the only precision machined parts in the ion mass analyzer assembly.
Curved Heated Ion Transfer Optics
US Patent:
2013001, Jan 17, 2013
Filed:
Feb 10, 2012
Appl. No.:
13/370513
Inventors:
Stephen ZANON - Campbell CA, US
Roy P. MOELLER - San Leandro CA, US
Urs STEINER - Branford CT, US
Felician MUNTEAN - Danville CA, US
Roy P. MOELLER - San Leandro CA, US
Urs STEINER - Branford CT, US
Felician MUNTEAN - Danville CA, US
Assignee:
Bruker Daltonics, Inc. - Billerica MA
International Classification:
H01J 49/26, H01R 43/00
US Classification:
250288, 29825
Abstract:
An ion optics assembly is formed by four quarter-circular profile elements, all of which are attach to the same reference plate. Consequently, all four elements remain aligned to the same reference plate. The four elements form a quarter-circular channel with quarter-circular quad electrodes. The quad electrodes receive electrical potential to form the field required to focus and maintain the ions at the center of the channel. Quarter-circular insulators are provided on all sides of the channel so as to seal the channel over its length from the interior of the mass spectrometer. A heater is provided at the entrance to the ion transfer optics, to prevent accumulation of ions on the poles. A thermal break is provided in the quad, so as to enable maintaining the front of the quad heated and the rest of the quad cooler.
Assembly For An Electrospray Ion Source
US Patent:
2014001, Jan 16, 2014
Filed:
Jul 16, 2012
Appl. No.:
13/550061
Inventors:
Roy P. MOELLER - San Leandro CA, US
Rohan THAKUR - Mountain View CA, US
Felician MUNTEAN - Danville CA, US
Maurizio A. SPLENDORE - Walnut Creek CA, US
Stephen ZANON - Campbell CA, US
Rohan THAKUR - Mountain View CA, US
Felician MUNTEAN - Danville CA, US
Maurizio A. SPLENDORE - Walnut Creek CA, US
Stephen ZANON - Campbell CA, US
Assignee:
BRUKER DALTONICS, INC. - Billerica MA
International Classification:
F23D 11/32
US Classification:
239690
Abstract:
An assembly for use in an electrospray ion source includes a capillary for guiding a flow of liquid generally containing analyte(s) of interest, which is to be electrosprayed into an ionization chamber, a first tube at least partially encasing the capillary such that a first conduit for guiding a first heatable gas is created proximate the capillary and a hollow member that has an internal evacuated space and is located at the outer circumference of the capillary such that heat transfer from the first heatable gas flowing proximate the capillary to the liquid in the capillary is impeded. The assembly provides a simple and lean/compact way of preventing excessive heat transfer to the liquid in the capillary of an electrospray ion source.