Forschungszentrum Julich Gmbh

Forschungszentrum Juelich Gmbh

Stephan Appelt

Martin Süfke

Ulrich Sieling

Nadim Joni Shah

Horst Halling

Friedrich-Wolfgang Hasing

Bernd Alexander Liebisch

Timur Unlu

Giovanni D'Orsaneo

Karl Zilles

Friedrich Wolfgang Häsing

Holger Kuhn

Daniel Gembris

Richard Patzak

Holger Kühn

Wolfgang Häsing

Nadim Jone Shah

Martin SÜFKE

The invention concerns a maser having an electromagnetic resonant circuit comprising a pick-up coil, a capacitance and a filter coil, an active medium of organic or maser-capable molecules in the pick-up coil as well as a population inversion device for generating a population inversion in the active medium.

CW maser with electromagnetic resonant circuit

The problem addressed by the invention is that of providing a coil having advantageous properties for an oscillating circuit, in particular for a measuring device for electromagnetic signals. This problem is solved in that the coil comprises an electric conductor, the ends of which form the two terminals of the coil. Wound sections of the electric conductor are twisted together, that is to say wound helically around one another. The electric conductor is in principle surrounded by insulation, for example made of plastic or varnish. As a result of the twisting, increases in spacing between adjacent conductor sections within the windings are achieved. This results in an improved quality of the coil.

High-quality coil

The invention relates to a measuring apparatus for detecting weak electromagnetic signals from a sample at low frequencies, specifically in the frequency range of 1 kHz-10 MHz, in particular, and to a measuring method. The problem addressed by the invention is that of providing an apparatus which can be used to detect weak electromagnetic signals from a sample, in particular in the frequency range of 1 kHz-40 MHz, with a good signal-to-noise ratio. For the solution, the measuring apparatus comprises an electromagnetic resonant circuit having a pick-up coil of low quality, a preferably tunable capacitance and a filter coil; the filter coil and the capacitance have a high quality of at least 100, advantageously at least 200, particularly preferably at least 500. Alternatively or additionally, the quality of the resonant circuit is at least 100, advantageously at least 200, particularly preferably at least 500. The quality of the filter coil and the quality of the capacitance exceed the quality of the pick-up coil, specifically at least by twice the amount. The measurement signal is then available at the two ends of the filter coil with a good signal-to-noise ratio.

Measuring apparatus for weak electromagnetic signals from a sample at low frequencies, in addition to a method

The invention concerns a method for hyperpolarizing lithium atoms in a mixture by optically pumping, in a sampling cell, atoms of a first type or alkali metal and by spin exchange between the optically pumped electron of the alkali metal and the lithium atom electron. The lithium atoms are preferably oxidized into Liions and accumulated. The nuclear spin polarization of the Liions can be transmitted to a nuclear spin of an anion. The invention also concerns a method for producing substances with nuclear spin polarization in general. In accordance with said method, lithium atoms are optically pumped from atoms of a first type of alkali metal in a sampling cell and hyperpolarized by spin exchange between the optical pumped electron of the alkali metal and the lithium atom electron, the lithium atoms being then oxidized into Liions. Then, the nuclear spin polarization of the Liions is transmitted to another nucleus of an anion. Thus it is possible to obtain hyperpolarized nuclei such as, for example,C,P orSi in solid or liquid phase, in large amounts and at high polarizing levels.

Hyperpolarization of lithium and other nuclei

The present invention relates to an imaging method and device for nuclear magnetic resonance. On the one hand, the method provides an image coding by means of an additional field which has, for each point of a two-dimensional grating surface within the sample, a different field strength value that occurs only once, as is the case, e.g., in fields based on fractal, surface-filling and space-filling curves. On the other hand, the read-out of the resonance behavior of a sample along a space-filling and/or surface-filling curve can be provided. In the first variant, a magnetic resonance (MR) image with a single high-frequency excitation without a time-varying gradient can be recorded, which in turn advantageously prevents the sound generation associated therewith. In the second variant, the sounds generated during read-out are advantageously shifted to another frequency range in which the human hearing is less sensitive. Furthermore, the device is relieved and the technical requirements with regard to it are reduced. In addition, it can be executed with known and existing devices.

Imaging method based on fractal surface-filling or space-filling curves

The invention relates to a method and a device for examining molecules by means of NMR spectroscopy. It is the object of the invention to be able to characterize a sample with a high resolution and comprehensively. The object is solved by a method and an associated device for examining a sample by means of nuclear magnetic spectroscopy by measuring heteronuclear and homonuclear J-couplings in a small magnetic field and by using the measured heteronuclear and homonuclear J-couplings for characterizing the sample.

Method for molecule examination by NMR spectroscopy

An apparatus for hyperpolarizing atomic nuclei through optical pumping has a cylindrical optical pumping cell having an inlet and an outlet spaced therefrom. A supply of a mixture of optically pumpable species and hyperpolarizable nuclei is connected to the inlet of the cell. A nozzle at an inlet of the optical pumping cell forms and injects a jet flow of the mixture into the optical pumping cell. It is then drawn out through the outlet such that the mixture touches the inner walls of the optical pumping cell only adjacent the outlet.

Method for the hyperpolarisation of atomic nuclei and device for implementing the method

The invention relates to a sample cell with a glass body comprising a gas inlet and a gas outlet and at least one orifice, a plane glass window is fused into the orifice, the shape and size of the window corresponds to the shape and size of the orifice, the orifice is limited by a rim, the rim is wider than the thickness of the window, the rim of the window is fused with the rim of the orifice. The invention further relates to a method of producing the sample cell. The window is inserted into the orifice. The rim of the orifice is heated several times from the exterior in such a way that the glass melts and a fused joint is formed between the window and the rim of the orifice. The sample cell produced by the method has a particularly rigid joint between the window and the glass body. Therefore, this glass cell is able to withstand pressures above 10 bar and allows the passage of light without lens effects owing to its plane-parallel windows. The sample cell is used in a polarizer for inert gas.

Test cell for a noble gas polarizer

The invention relates to a polarizer for noble gases comprising a glass sample cell and a pressure chanter in which the sample cell is located. High pressure and accompanying broadband or narrow-band lasers can be similarly provided in an optimal manner. To this end, the polarizer is operated at pressures of 30 bar and higher.

High pressure polarizer for hyperpolarizing the nuclear spin of noble gases

The invention concerns a device for the determination of the absolute polarisation of alkali metal atoms. The device can inter alia be used for the diagnosis of alkali metal polarisation in a polariser for inert gases. The device includes a detection laser, which together with a &lgr;/4 plate creates circularly polarised light. A sensor for the measurement of the light absorbed by the sample of the polariser is provided. A Helmholtz coil pair serves for the creation of a static magnetic field B . An oscillating magnetic field is created with an RF coil. A gradient coil serves for the creation of a linear magnetic field gradient. Various optical components are present. An electronic processor effects the determination of the absolute polarisation of the alkali metal atoms. All the said components with the exception of the Helmholtz coils are firmly mounted onto a platform which can be moved parallel to the direction of the B field. Means for controlling the temperature of the laser for the detection of the polarisation of the alkali metal atoms are provided. The means for controlling the temperature of the laser for the detection of the polarisation of the alkali metal atoms include a temperature sensor, with which the temperature of the laser is measured, a heating/cooling device, with which the laser is heated or cooled, and also a control device, which controls the heating/cooling device depending on the measured temperature of the laser, so that the temperature of the laser is held constant. Compared to the state of the art, faster and better measurement results can thus be achieved.

Growing community of inventors

Aachen-Soers, Germany

Stephan Appelt