Abstract:
The present invention relates to an anion generating and electron capture dissociation apparatus using cold electrons, which uses an MCP electron multiplier plate for generating an electron beam for ionization within an ion trap of a Fourier transform ion cyclotron resonance mass spectroscope, injects ultraviolet photons emitted from an ultraviolet diode across the entire surface of the MCP electron multiplier plate, uses an electron focusing lens to focus and inject an electron beam into the trap, and generates an ECD reaction by coupling electrons to molecules having multiple positive charges using a low energy electron beam emitting apparatus for the negative ionization of neutral molecules in the ion trap. The anion generating and electron capturing and analyzing apparatus of the present invention, which uses cold electrons and is configured of a cold electron generating module which generates a large number of cold electrons from ultraviolet photons emitted into a mass spectroscope in a high vacuum state, comprises a plurality of ultraviolet diodes emitting ultraviolet photons in the mass spectroscope, an MCP electron multiplier plate inducing and amplifying an initial electron emission of ultraviolet photons from the ultraviolet diodes, and generating a high capacity electron beam from a back plate, an electron focusing lens for focusing the electron beam amplified through the MCP electron multiplier plate, and a grid for adjusting the energy and current of electrons.
Abstract:
The present invention relates to an ultraviolet diode and an atomic mass analysis ionization source collecting device using an MCP. In the manufacturing of a portable atomic mass analyzer, an object of the present invention is to use an MCP electron multiplier plate, whereby ultraviolet photons emitted from an ultraviolet diode are irradiated on a front surface plate of the MCP electron multiplier plate to induce primary electrons, an amplified electron beam is collected from the electrons, and an electron beam is generated at a low temperature and low power and having a discharge time that is accurately controlled. The atomic mass analysis ionization source collecting device using an ultraviolet diode and an MCP according to the present invention comprises: an ultraviolet diode emitting ultraviolet rays by means of supplied power; an MCP electron multiplier plate inducing and amplifying primary electron discharge from ultraviolet photons from the ultraviolet diode, and collecting a large amount of electron beams from an MCP reverse surface plate; an electron condenser lens condensing the electron beam amplified through the MCP electron multiplier plate; an ion trap atomic mass separator ionizing gas sample molecules by means of an electron beam injected through the electron condenser lens; and an ion detector performing detection of ions separated from the ion trap atomic mass separator, by means of an atomic mass spectrum.
Abstract:
A cathode configuration for emission of electrons has a reaction zone connected to an entrance opening for the supply of neutral particles. The opening communicates with the cathode configuration for the ionization of the neutral particles and an ion extraction system communicates with the reaction zone. Ions from the extraction system are sent to a detection system and a mechanism for the evacuation of the mass spectrometer arrangement. The cathode configuration includes a field emission cathode with an emitter surface, wherein at a short distance from this emitter surface, an extraction grid is disposed for the extraction of electrons, which grid substantially covers the emitter surface. The emitter surface encompasses herein at least partially a hollow volume such that a tubular structure is formed.
Abstract:
In an analytical spectrometer in which accelerated electrons are used to ionize analytes, a non-radioactive electron source uses a gas discharge to generate the electrons. The gas discharge is located in a substantially hermetic source chamber and the free electrons in the plasma of the gas discharge are accelerated in an electric acceleration region towards a partition wall which separates the source chamber from a reaction chamber. The partition wall is permeable to the accelerated electrons but impermeable to gas in the source chamber so that the electrons penetrate the partition wall into the reaction chamber and generate primary ions that chemically ionize the analytes.
Abstract:
An improved quadrupole mass spectrometer is described. The improvement lies in the substitution of the conventional hot filament electron source with a cold cathode field emitter array which in turn allows operating a small QMS at much high internal pressures then are currently achievable. By eliminating of the hot filament such problems as thermally nullcrackingnull delicate analyte molecules, outgassing a nullhotnull filament, high power requirements, filament contamination by outgas species, and spurious em fields are avoid all together. In addition, the ability of produce FEAs using well-known and well developed photolithographic techniques, permits building a QMS having multiple redundancies of the ionization source at very low additional cost.
Abstract:
An electron multiplier with a source for spontaneously generating electrons is used as an electron source for an ionization source in a mass spectrometer or the like. The electron multiplier can be a microchannel plate, in which case it produces a wide electron beam. The microchannel plate can be acid-leached to provide a surface for spontaneous generation of electrons, or the first strike surface can be coated with an alkali-containing material. The electron source can be tuned by providing an electrode for rejecting electrons having too high an energy and a grid for rejecting electrons having too low an energy.
Abstract:
A mass spectrometer 20 includes an electron multiplier 30 for producing an electron avalanche 58 directed toward an ionization region 38. A sample 40 enters the ionization region 38 through a sample inlet 68. In the ionization region 38 the electron avalanche 58 collides with the sample 40 and produces ions 60. A start detector 56 detects the electron avalanche 58 and provides a start signal. The ions 60 exit the ionization region 38 and enter a flight region 26. The ions 60 flow through the flight region 26 and interact with a stop detector 42. The stop detector 42 generates a stop signal in response to being activated. A low pressure enclosure 22 encloses at least the electron multiplier 30 and the ionization region 38. The start and stop signals are supplied to an analysis system for determining the mass of the sample using time-of-flight mass spectrometry.
Abstract:
A quadrupole is filled with ions and the ions are cooled by applying a pressure and gas flow within the quadrupole. Ions are trapped in the quadrupole by applying a DC voltage and an RF voltage to quadrupole rods of the quadrupole, one or more DC voltages to a plurality of auxiliary electrodes of the quadrupole, and a DC voltage and an RF voltage to an exit lens at the end of the quadrupole. The ions are coherently oscillated after the filling and cooling by applying a coherent excitation between at least two rods of the quadrupole rods. The coherently oscillating ions are axially ejected through the exit lens and to a destructive detector for detection by changing one or more voltages of the one or more DC voltages of the plurality of auxiliary electrodes and changing the DC voltage of the exit lens.
Abstract:
본 발명은 냉전자를 이용한 음이온 발생과 전자포획 분해장치에 관한 것으로, 푸리에변환 이온싸이클로트론공명 질량분석기의 이온트랩 내에서 이온화를 위한 전자빔 발생을 하기 위하여 MCP전자증배판을 사용하되, 자외선다이오드에서 방출하는 자외선 광자를 MCP 전자증배판 전면에 주사하여 증폭된 전자빔을 획득하고, 전자집속렌즈를 이용하여 트랩내로 전자빔을 집속하여 주입하고, 이온트랩 내에서 중성분자의 음이온화를 목적으로 하는 저에너지 전자빔 방출 장치와 다중양전하를 띈 분자에 전자를 결합시켜 ECD 반응 생성하게 한다. 본 발명은 고진공 상태의 질량분석기 내부에 조사된 자외선광자로부터 많은 수의 냉전자를 발생하는 냉전자발생모듈로 구성된 냉전자를 이용한 음이온 발생과 전자포획 분해장치에 있어서, 질량분석기 내에 자외선 광자를 방출하는 다수의 자외선다이오드; 자외선다이오드로부터 자외선 광자들의 초기 전자방출을 유도 및 증폭하여 후면판에서 대량의 전자빔을 발생시키는 MCP 전자증배판; MCP 전자증배판을 통해 증폭된 전자빔을 집적하는 전자집적렌즈; 전자의 에너지와 전류를 조정하는 그리드;를 포함하여 이루어진다.
Abstract:
Mass analysers and methods of ion detection for a mass analyser are provided. An electrostatic field generator provides an electrostatic field causing ion packets to oscillate along a direction. A pulse transient signal is detected over a time duration that is significantly shorter than a period of the ion oscillation or using pulse detection electrodes having a width that is significantly smaller than a span of ion harmonic motion. A harmonic transient signal is also detected. Ion intensity with respect to mass-to-charge ratio is then identified based on the pulse transient signal and the harmonic transient signal.