Abstract: An explosive detection system in which vapor leaking from luggage is sampled by a sampling probe, negative corona discharge is used to ionize the vapor, and a mass spectrometer is used to detect the ionized vapor, thereby judging whether an explosive is present or not.

Abstract: A mass spectrometer including a sprayer for spraying a sample solution, a needle electrode for ionizing the sample contained in the sample solution, an aperture for introducing the ions of the sample into a lower pressure region having a pressure lower than the pressure of a region in which the needle electrode is disposed, and a mass spectrometric apparatus for analyzing the ions introduced from the aperture. A direction of a spray caused by the sprayer is almost perpendicular to or at an angle with respect to a center axis of the aperture, and a tip of the needle is disposed facing to an electrode having the aperture.

Abstract: A mass spectrometer including a sprayer for spraying a sample solution, a needle electrode for ionizing the sample contained in the sample solution, an aperture for introducing the ions of the sample into a lower pressure region having a pressure lower than the pressure of a region in which the needle electrode is disposed, and a mass spectrometric apparatus for analyzing the ions introduced from the aperture. A direction of a spray caused by the sprayer is almost perpendicular to a center axis of the aperture and a tip of the needle is disposed facing to an electrode having the aperture.

Abstract: A mass spectrometer comprising an ionization means For ionizing sample compounds to be analyzed mass spectro-scopically in an atmospheric pressure, a sample solution supply means for supplying a solution containing the sample compounds to the ionization means, means for feeding the ions formed by the ionization means through an aperture disposed in an electrode into a vacuum region and a ion trap type mass spectroscopic means for mass spectroscopically analyzing ions entered through the aperture into the vacuum region, in which an ion decelerating electric field forming means is disposed between the electrode disposed with the aperture and an electrode disposed with an ion entrance opening for entering the ions into the ion trap type mass spectroscopic means for forming an electric field for decelerating the ions, and the ions injected to the ion trap mass spectroscopic means is lowered.

Abstract: A method for performing a mass calibration under an application of a desired ion peak position of mass spectrum attained by a mass scanning of ions of substance having a known value of m/z and the known value of m/z is added with a step for ejecting an amount of unnecessary ions not contributing to the aforesaid mass calibration accumulated in the aforesaid ion trap type mass analysis region prior to the aforesaid mass scanning operation. An accumulation of a large amount of unnecessary ions in the ion trap type mass analysis region is restricted, a disturbance of electric field in the ion trap mass analysis region generated under an influence of a spatial charge caused by accumulation of the unnecessary ions can be prevented and the aforesaid mass calibration can be performed in an easy and accurate manner.

Abstract: A mass spectrometer includes a sample supplier which supplies a sample solution, the sample solution including a solvent, ions, and a solute, the solute being a sample to be analyzed, an ion converter, disposed after the sample supplier, which converts the ions in the sample solution into gaseous ions, an ion source, disposed after the ion converter, which ionizes the sample in the sample solution, thereby producing sample ions, a mass analyzer which analyzes masses of the sample ions produced by the ion source, and an ion blocking electrode which prevents the gaseous ions produced by the ion converter from reaching the ion source, thereby preventing the mass analyzer from analyzing masses of the gaseous ions produced by the ion converter.

Abstract: A mass spectrometer comprising an ionization means for ionizing sample compounds to be analyzed mass spectro-scopically in an atmospheric pressure, a sample solution supply means for supplying a solution containing the sample compounds to the ionization means, means for feeding the ions formed by the ionization means through an aperture disposed in an electrode into a vacuum region, and an ion trap type mass spectroscopic means for mass spectroscopically analyzing ions entered through the aperture into the vacuum region, in which an ion decelerating electric field forming means is disposed between the electrode disposed with the aperture and an electrode disposed with an ion entrance opening for entering the ions into the ion trap type mass spectroscopic means for forming an electric field for decelerating the ions, and the ions injected to the ion trap mass spectroscopic means is lowered.

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: A mass spectrometer includes a sample passage through which a sample solution flows towards a tip of the sample passage, a gas passage which produces a gas flow along the sample passage towards an orifice of the gas passage, a gas supplier which supplies a gas to the gas passage so that the gas flow has a velocity effective for spraying the sample solution near the tip of the sample passage, and an analyzer which analyzes a mass of gaseous ions formed from the sample solution sprayed by the gas flow. The gas flow has a characteristic value F/S between 350 meters/second (m/s) and 700 m/s, where F is a flow rate of the gas at standard conditions (20.degree. C., 1 atmosphere), and S is a difference between a cross section of the orifice and a cross section of the sample passage at the orifice. An exposed length of the sample passage between an external opening of the orifice and the tip of the sample passage may be between -0.25 mm and 1.2 mm.

Abstract: A mass spectrometric apparatus includes a device for supplying a sample solution to an outlet, the sample solution including a solvent and a solute, a first ionization device for receiving the sample solution from the outlet and electrospraying the received sample solution, thereby ionizing at least a portion of the received sample solution, a second ionization device for receiving at least a portion of the electrosprayed sample solution produced by the first ionization device and ionizing at least a portion of the received electrospayed sample solution, thereby producing ions, and a mass spectrometric device for receiving at least some of the ions produced by the second ionization device and analyzing masses of the received ions.

Abstract: A mass spectrometer comprising a passage through which a sample solution flows, the passage including a capillary having an open tip, the sample solution flowing through the capillary out of the open tip of the capillary, a gas passage which forms a gas flow around the open tip of the capillary, the gas flow spraying the sample solution flowing out of the open tip of the capillary, a first electrode which contacts the sample solution flowing in the passage and applies an electric potential to the sample solution flowing in the passage, a second electrode disposed around the capillary near the open tip of the capillary, the second electrode being downstream from the first electrode with respect to a direction in which the sample solution flows in the passage, there being no gap extending downstream from the open tip of the capillary to the second electrode in a direction in which the sample solution flows out of the open tip of the capillary, the second electrode being electrically isolated from the sample sol

Abstract: A mass spectrometer in which, in order to reduce noise due to other particles (large charge droplets, neutral particles, photons, or the like), the orbit of ions and the orbit of other particles are separated from each other in the inside of a mass analysis region so as to make it possible to prevent the other particles from reaching an ion detection region without using any deflector.

Abstract: In an analytical apparatus, an ion trap mass spectrometer and a detector for detecting ions separated in the mass spectrometer are installed in different chambers. Ions generated from an ion source and passing through two differential pumping chambers into a third chamber containing the detector are deflected from their initial trajectory into the mass spectrometer in a fourth chamber for separation. In a first embodiment, the separated ions are returned along the same path into the detector in the third chamber. According to a second embodiment, the detector is located along the path of ion travel beyond the mass spectrometer, and the separated ions pass through a second orifice in the mass spectrometer and into the detector in the third chamber.

Abstract: A mass spectrometer comprising an ionization means for ionizing sample compounds to be analyzed mass spectro-scopically in an atmospheric pressure, a sample solution supply means for supplying a solution containing the sample compounds to the ionization means, means for feeding the ions formed by the ionization means through an aperture disposed in an electrode into a vacuum region, and anion trap type mass spectroscopic means for mass spectroscopically analyzing ions entered through the aperture into the vacuum region, in which an ion decelerating electric field forming means is disposed between the electrode disposed with the aperture and an electrode disposed with an ion entrance opening for entering the ions into the ion trap type mass spectroscopic means for forming an electric field for decelerating the ions, and the ions injected to the ion trap mass spectroscopic means is lowered.

Abstract: A method in which cutting of small droplets, neutral particles or photons through to a slit provided between a differential pumping portion and a mass analysis portion is combined with slight deflection of ions just before introduction of the ions into the mass analysis portion so that noises are greatly reduced without reduction of signals to thereby improve the signal-to-noise ratio which is an index of detecting sensitivity or lower limit.

Abstract: In a mass spectrometer using a sonic spray ion source, a technique of controlling the density of droplets in a nebulized sample solution which is passed into a mass spectrometer at high vacuum to an appropriate value to thereby reduce analysis noises is disclosed. A sample solution in a sample solution injection unit 1 is introduced into a capillary 2 disposed in an ion source 6. A gas is introduced from a gas supply unit 4 by way of a gas pipe 5 into the ion source 6 and is caused to flow along the outer circumferential surface at the top end of the capillary 2 and is jetted out from the orifice 3 as a gas flow into atmospheric air. The sample solution jetted from the top end of the capillary 2 is ionized by the gas flow in the atmospheric air.

Abstract: A semi-micro liquid chromatograph/mass spectrometer apparatus has an ion source. The space from the end portion of a flow passage of a liquid chromatograph shell to a vaporization portion is closed so as to prevent the inflow of a gas from outside the ion source into the space. Further, the nebulization and vaporization portions are joined together and heated by a common heater. Dilution of a sample to be analyzed is prevented, and high sensitivity detection becomes possible in a low velocity liquid chromatograph/mass spectrometer.

Abstract: An automatic-transmission control for outputting a switch signal of a shift position is produced as follows. A first terminal unit includes small-power fixed contacts coupled with small-power contacts of a connector through a coupling portion, is formed. A second terminal unit, which includes large-power fixed contacts coupled with large-power contacts of a connector through a coupling portion, is formed. A positioning resin block is formed to at least one of the first and second terminal units. The first and second terminal units are laminated through the positioning block. A switch body and a connector are molded upon inserting the laminated first and second terminal units in a molding die. The switch body and the connector are separated by cutting the coupling portion.

Abstract: A mass spectrometer employing an ion source includes a capillary for spraying therethrough liquid into the atmospheres and an orifice through which a portion in the vicinity of a tip of the capillary is inserted, the orifice being designed in such a way that gases are caused to flow up to the tip of the capillary along a peripheral wall face of the capillary. The flow rate of gas in the vicinity of the tip of the capillary is about the sonic velocity, and a voltage is applied across the liquid flowing through the capillary and the orifice or an electrode arranged in the vicinity of the tip of the capillary.

Abstract: A mass spectrometer comprising a capillary electrophoresis region for separating a solution containing molecules of sample by capillary electrophoresis in a capillary, a nebulization region for nebulizing the solution containing molecules of the sample under an atmospheric pressure from the end of the capillary and forming liquid droplets of the solution containing the molecules of the sample, a vaporization region for vaporizing the liquid droplets under an atmospheric pressure to form gaseous molecules of the sample, a chemical ionization region for forming ions relevant to the molecules of the sample under the atmospheric pressure or the reduced pressure by a chemical reaction between the ions attributable to the gaseous molecules present in the atmosphere and the gaseous molecules of the sample, and a vacuum region having a sample aperture for introducing the ions formed by the chemical ionization means and incorporating a mass analysis region for mass analysis of ions introduced from the sample aperture.