Hitachi, Ltd.

Masataka Koga

Yukio Okamoto

Konosuke Oishi

Takehiko Kitamori

Toyoharu Okumoto

Makoto Yasuda

Tsuyoshi Nishitarumizu

Kazumichi Imai

Tetsuya Matsui

Seiichi Murayama

Hiromi Yamashita

Masaharu Sakagami

Masatoshi Kitagawa

Kenji Yokose

Satoshi Shimura

Hideaki Koizumi

Masamichi Tsukada

Tsutomu Komoda

Tsuguo Sawada

Yoji Arai

Kazuo Yasuda

Takashi Iino

Kounosuke Oishi

Yu-Ming Hsueh

Shinji Mayama

Takahashi Iino

Katuo Kawachi

Jiaqi Wu

A particle counting apparatus for counting a total particle counting value contained in a liquid sample comprising, a flow cell in which the liquid sample flows, a light source for irradiating a light beam to the sample liquid in the flow cell, a detector for detecting pulse-wise signal scattered from the particles by the irradiating of the light beam, and a computer for obtaining the total particle counting value contained in the liquid sample as a counting value measured when the top end of the liquid sample is irradiated with the light beam and the plural particles in the top end does not overlapped in the light beam, multiplied by a coefficient.

Particle counting apparatus for a total counting of particles contained

A plasma mass spectrometer generates an aerosol of a sample, by dissolving the sample in a liquid solvent, and spraying the liquid into a spray chamber via a nebulizer. The solvent condenses in the spray chamber and an aerosol of the sample then passes through a supply tube to a plasma torch. Microwave power from an output on the plasma torch converts the aerosol to a plasma, and the plasma passes to an analyzer. If microwave radiation reached the spray chamber, it would cause heating of the solvent which may evaporate it so that the solvent would be present in the plasma. Therefore, there is a wall between the spray chamber and the plasma torch and microwave output which blocks such microwave radiation.

Plasma mass spectrometer

In the analysis of a specimen gas for at least one impurity, the specimen is fed to a microwave-induced plasma and the plasma is analyzed for the impurity. The plasma is formed by gases fed to it via an inner tube and an outer tube around said inner tube. The specimen is fed in undiluted form via the inner tube and a second gas which may be a standard gas is fed via the outer tube. The specimen gas and the second gas have compositions which are the same as to at least 75% by volume, e.g. are both air. A variety of analysis processes is made available.

Method and apparatus for analysis of gases using plasma

The present invention is applied to an analyzer according to which a sample to be analyzed is moved through a capillary tube in liquid chromatography or capillary-zone electrophoretic method. The capillary tube has a separation zone and a detection zone. The capillary tube in the detection zone has a section in which it can vibrate and both ends of this section are fixed. Analytes of the sample introduced into the analyzer are separated from each other in the separation zone. When each of the separated analytes is led to the area irradiated with beam in the detection zone, the capillary tube in the detection zone vibrates. This vibration phenomenon is brought about by tension fluctuation of the capillary tube caused by intermittent irradiation of the detection zone with an excitation beam and absorption of the excitation beam by the analyte. Concentration of analytes in the sample can be measured by detecting amplitude of the vibration.

Analytical method and apparatus using capillary tube

A standard containing the same elements as a sample is prepared. Concentrations of the elements of the standard are known previously. When signal intensities of an element of the standard solution and the sample exceed an upper limit of a pulse counter of an element analyzing apparatus, a transmitting rate of a passage, through which ionized elements of the standard and the sample pass, is controlled to be less than the ordinal transmitting rate of the passage in synchronism to the passing time of the elements. The concentrations of the elements of the sample is calculated based on output signals of the pulse counter concerning the elements of the standard and the sample and known concentration of the standard.

High sensitive element analyzing method and apparatus of the same

The power density of a pulsed laser beam for irradiating a sample is adjusted to break down the sample into the form of a plasma. After the momentary breakdown of the sample into the form of a plasma, ions are generated having a high charge. Then, after a certain time elapses, the ions having a high charge recombine with the electrons in the plasma to provide monovalent or low valent ions. These low valent ions are taken out of the plasma and introduced to a mass spectrometric apparatus.

Method and apparatus for mass spectrometric analysis

A mass spectrometer using a plasma ion source for analyzing an ultra-trace element includes a plasma generation system for generating a plasma including the composition of a sample, an ion beam formation system for extracting ions in the form of a beam from the plasma generating the ions, a mass spectrometry system for performing mass spectrometry of the ion beamn, and an ion detection system for detecting the ions subjected to the mass spectrometry, in which a lens system made up of a cylindrical first electrode, a cylindrical second electrode with a photon stopper disposed on the central axis thereof, and a cylindrical third electrode is further provided between the ion beam formation system and the mass spectrometry system. By the provision of the lens system, the ions generated in the plasma are transported more efficiently to the side of the mass spectrometry system and by the provision of the photon stopper in the above described position, it is achieved, with a simpler structure, to prevent photons from entering the ion detection system.

Mass spectrometer using plasma ion source

A method of and an apparatus for analyzing a granular material contained in a sample of a medium such as water produced by an ultra-pure water producing apparatus includes the steps of adding energy to granular materials contained in a sample which is mixed with the medium, wherein the energy is set to be lower than the breakdown threshold of the medium and to be higher than the breakdown threshold of the granular materials, detecting ions which are generated with the breakdown of the granular materials by using a pair of positive and negative electrodes; and analyzing characteristics of the granular materials based on the ions.

Method of and apparatus for analyzing granular materials

A microwave induced plasma source includes a coaxial waveguide made up of a cylindrical outer conductor and an inner conductor which has the form of a helical coil, a discharge tube inserted into the helical coil in the axial direction thereof, and having an inner tube for introducing a sample and an outer tube for introducing a plasma gas so that a double tube structure is formed, a discharge-tube cooling device for causing a cooling gas to flow along the outer periphery of the discharge tube in directions parallel to the axis thereof, and a microwave power source for supplying microwave power to the coaxial waveguide. When the microwave induced plasma source is used as the light source of a spectrometer or the ion source of a mass spectrometer, a trace element can be readily determined qualitatively or quantitatively.

Microwave induced plasma source

A plasma source mass spectrometer in which ions in a plasma generated in a high pressure (.ltoreq.1 atm) region are introduced into a low pressure (.ltoreq.10.sup.-5 Torr) region to analysis the ion mass includes a moderate pressure (.gtoreq.10.sup.-3 Torr) region which is provided between the high pressure region and the low pressure region. The plasma generated in the high pressure region is diffused to the moderate pressure region in order to produce a diffused plasma. Ions are extracted from the diffused plasma by an ion extraction electrode having an ion extraction opening. In the vicinity of the ion extraction opening a convex-shaped toward the diffused plasma whereby ion sheath is formed, whereby the ions can be extracted toward the low pressure region with a high efficiency.

Plasma source mass spectrometer

In atomic absorption spectrophotometers such as Zeeman atomic absorption spectrophotometer, the present invention is characterized in that the correction timing of background absorption in sample light is made to coincide with that of reference light so as to improve the accuracy of the output signals of the spectrophotometer. To accomplish this object, the present invention constitutes a calculation processing unit for storing and calculating signals by means for separating one signal consisting of sample signals and reference signals applied thereto from amplification means for amplifiying photoelectrically converted signals into sample and reference signals, and storing them, means for calculating respectively the mean values of two time adjacent signals of one of the sample and reference signals to prepare a signal of the mean values, and means for calculating the difference of the logarithmic converted values of the signals of the other of the sample and reference signals and those of the signals of the signal of the mean values at the same points of time, and obtaining correction signals of background absorption.

Atomic absorption spectrophotometer

A plasma trace element spectrometer comprises a microwave generator for generating microwave power, a microwave feeder for guiding and transforming the generated microwave power into microwave power of TE.sub.01 mode and supplying the microwave power of TE.sub.01 mode, a plasma producer having, at one end, an introduction port for a carrier gas and a sample and at the other end an opening and being cooperative with the supplied microwave power of TE.sub.01 mode to produce plasma of the carrier gas and sample introduced through the introduction port, and a spectrometer for analyzing constituent elements of the sample by measuring the produced plasma by way of the opening.

Trace element spectrometry with plasma source

There is provided an atomic absorption spectrophotometer wherein a magnetic field having a suitable value is applied to a light source radiating the emission spectral light of the atom to be analyzed in the advance direction of the radiated light in order to cause the Zeeman effect so that the wavenumber of a component which is included in the spectra shifted in wavenumber and which is varied to have a smaller wavenumber may coincide with or approach the wavenumber whereat the absorption spectrum is maximized, thereby the sensitivity of the atomic absorption being raised, the linear region of the working curve being improved, and the emission spectral light being stabilized.

A double polarized light beam spectrophotometer of a light-source modulation type. A modulated light beam emitted by a light source is conducted through specimen atom vapor generated by a graphite atomizer. Wavelength of light undergone atom absorption is selected and spatially separated into a pair of linearly polarized light beams perpendicular to each other. The pair of the linearly polarized light beams separated are alternately passed through a chopper and received by a photoelectric conversion device to be converted into electric signals which are utilized for determining atomic absorption of the specimen. The phase of modulation of light radiated from the light source is synchronized with phase of a current supplied to the graphite atomizer for heating thereof and the switching timing of the chopper.

Double polarized light beam spectrophotometer of light source modulation

A spectral source comprises a lamp containing an anode and a cathode in an inert gas. The anode and cathode are different in shape and connected to a high-frequency power source to produce a high-frequency discharge between the anode and cathode to cause both sputtering of the cathode and excitation of a radiation having the spectrum according to the material sputtered from the cathode. The application of solely high-frequency power prevents adherence of the sputtered material to the interior walls of the lamp bulb thereby allowing a reduction of the dimensions of the lamp bulb, prolongating the life time of the lamp and increasing the stability and intensity of the radiation. A magnetic field may be applied to the radiation for Zeeman modulation. Due to the relatively small dimensions of the lamp bulb, relatively small and inexpensive magnets may be used.

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Katsuta, Japan

Masataka Koga