Abstract: A powder replenisher includes a powder replenishment container to be replenished with powder. A pressure adjuster increases and decreases operating pressure applied to a variable capacity portion. A powder measuring instrument measures an amount of the powder that replenishes the powder replenishment container. A controller performs a precise replenishing mode in which, after the controller determines that the powder replenishment container is replenished with the powder in a predetermined amount, while the controller controls the powder measuring instrument to measure the amount of the powder inside the powder replenishment container, the controller controls the pressure adjuster to replenish the powder replenishment container with the powder in a target amount.

Abstract: An “ion trap-TOF/MS” capable of calibrating the observed mass for each of an ion trap and a TOF. In the ion trap-TOF/MS, sample ions having known mass numbers and ionized by an ion source are trapped within an ion trap. Auxiliary AC voltages having a frequency component ? are applied to the end cap electrodes of the ion trap to expel unwanted ions out of the ion trap. A measurement process is carried out by applying DC voltages to the ring electrode and the end cap electrodes to expel an ion remaining within the ion trap, and measuring the mass number of the expelled ion by the time-of-flight mass spectrometer. The measurement process is repeated while changing the frequency component ?, and the ion signal intensity measured by the time-of-flight mass spectrometer is compared with a previously stored threshold, thereby making calibration of the frequency component ? for the ion having the known mass number. Thus, the calibrating of the observed mass can be realized for each of the ion trap and the TOF.

Abstract: In a mass spectrometer utilizing an atmospheric pressure ion source, the amount of un-vaporized droplets that reach a mass spectrometric section is reduced. A mass spectrometer comprises: an ionization section for ionizing a sample at substantially atmospheric pressure; a first and a second intermediate pressure section in which the pressure is maintained lower than the pressure in said ionization section; a high vacuum section in which the pressure is maintained lower than the pressure in said intermediate pressure section and in which a mass spectrometric means for subjecting ions to mass spectrometry is disposed; a first pore electrode disposed between said ionization section and said first intermediate pressure section; an intermediate pore electrode disposed between said first intermediate pressure section and said second intermediate pressure section; and a second pore electrode disposed between said second intermediate pressure section and said high vacuum section.

Abstract: An “ion trap-TOF/MS” capable of calibrating the observed mass for each of an ion trap and a TOF. In the ion trap-TOF/MS, sample ions having known mass numbers and ionized by an ion source are trapped within an ion trap. Auxiliary AC voltages having a frequency component ? are applied to the end cap electrodes of the ion trap to expel unwanted ions out of the ion trap. A measurement process is carried out by applying DC voltages to the ring electrode and the end cap electrodes to expel an ion remaining within the ion trap, and measuring the mass number of the expelled ion by the time-of-flight mass spectrometer. The measurement process is repeated while changing the frequency component ?, and the ion signal intensity measured by the time-of-flight mass spectrometer is compared with a previously stored threshold, thereby making calibration of the frequency component ? for the ion having the known mass number. Thus, the calibrating of the observed mass can be realized for each of the ion trap and the TOF.

Abstract: An ion-trap mass analyzing apparatus having means for generating ion-capture electric fields asymmetrical with respect to a reference plane containing a central point of a ring electrode and perpendicular to a central axis of the ring electrode in the inside of an ion trap to resonantly amplify ions rapidly to emit the ions from the ion trap in a short time to thereby permit high-sensitive high-accurate mass analysis stably regardless of the structural stability of ions as a subject of analysis.

Abstract: In a mass spectrometer utilizing an atmospheric pressure ion source, the amount of un-vaporized droplets that reach a mass spectrometric section is reduced. A mass spectrometer comprises: an ionization section for ionizing a sample at substantially atmospheric pressure; a first and a second intermediate pressure section in which the pressure is maintained lower than the pressure in said ionization section; a high vacuum section in which the pressure is maintained lower than the pressure in said intermediate pressure section and in which a mass spectrometric means for subjecting ions to mass spectrometry is disposed; a first pore electrode disposed between said ionization section and said first intermediate pressure section; an intermediate pore electrode disposed between said first intermediate pressure section and said second intermediate pressure section; and a second pore electrode disposed between said second intermediate pressure section and said high vacuum section.

Abstract: An ion-trap mass analyzing apparatus having means for generating ion-capture electric fields asymmetrical with respect to a reference plane containing a central point of a ring electrode and perpendicular to a central axis of the ring electrode in the inside of an ion trap to resonantly amplify ions rapidly to emit the ions from the ion trap in a short time to thereby permit high-sensitive high-accurate mass analysis stably regardless of the structural stability of ions as a subject of analysis.

Abstract: An ion-trap mass analyzing apparatus having means for generating ion-capture electric fields asymmetrical with respect to a reference plane containing a central point of a ring electrode and perpendicular to a central axis of the ring electrode in the inside of an ion trap to resonantly amplify ions rapidly to emit the ions from the ion trap in a short time to thereby permit high-sensitive high-accurate mass analysis stably regardless of the structural stability of ions as a subject of analysis.

Abstract: An ion-trap mass analyzing apparatus having means for generating ion-capture electric fields asymmetrical with respect to a reference plane containing a central point of a ring electrode and perpendicular to a central axis of the ring electrode in the inside of an ion trap to resonantly amplify ions rapidly to emit the ions from the ion trap in a short time to thereby permit high-sensitive high-accurate mass analysis stably regardless of the structural stability of ions as a subject of analysis.

Abstract: Disclosed is an ion trap mass spectrometer improved to obtain a high sensitivity without the lowering of resolution. By fitting a mesh electrode to an aperture (an ion sampling aperture or an ion extracting aperture) made in endcap electrodes constituting an ion trap mass analysis region, a radio frequency electric field in the mass analysis region is not disturbed even if the diameter of the aperture is set to a large value to heighten ion transmission efficiency. By fitting a shield electrode for preventing collision of ions with an insulated ring constituting an outer wall of the mass analysis region, charging up of the insulated ring is prevented to improve stability of detection signals. Furthermore, by arranging a shield member for shielding stray charged particles detouring through the circumference of the mass analysis region to approach an ion detector, generation of noises based on these stray charged particles is prevented.

Abstract: 2,2-Dimethoxy-2-phenylacetophenone is prepared by reacting benzil with dimethyl sulfate and alkali metal methylate in a nonpolar organic solvent (e.g. xylene, cyclohexane) in the presence of one or more of catalysts selected from the group consisting of polyethylene glycol, a polyethylene glycol dialkyl ether and a crown ether. The reaction can be carried out more preferably in the presence of diglyme or triglyme or a mixture of diglyme or triglyme and polyethylene glycol.