Abstract: A cryostat assembly (1) for a superconducting magnet assembly, with a helium tank (2) for liquid helium, whereby the superconducting magnet assembly (6) is located in the helium tank (2), with a nitrogen tank (3) for liquid nitrogen, whereby the nitrogen tank (3) encloses the helium tank (2), and with at least one access tube (4) in which the current lead is mounted through which current can be lead from the room-temperature warm area of the cryostat (1) into the superconducting magnet assembly (6), whereby the current lead assembly comprises at least one current lead with a normal conductor part (13) and a superconductor part (14) made of HTS material, characterized in that a terminal (12) of the at least one current lead, through which the normal conductor part (13) is electrically connected with the superconductor part (14) is thermally coupled with a wall of the nitrogen tank (3).

Abstract: A control circuit (1) for driving a gas discharge lamp, in particular a fluorescent lamp (FL), having a controllable converter (2) for converting a DC voltage to an AC voltage and having two feed lines (3, 4), which are connected on the AC-voltage side to the converter (2), and between which the gas discharge lamp can be connected, an inductor (L1), a first capacitance (C1) and a first controllable switching element (T1) being connected in series in the feed lines (3, 4). The feed lines (3, 4) are connected to one another via a second switching element (T2).

Abstract: A cryostat configuration for keeping cryogenic fluids in at least one cryocontainer, comprising an outer shell and a neck tube containing a cold head of a cryocooler, wherein the coldest cold stage of the cold head is disposed in a contact-free manner relative to the neck tube and the cryocontainer, and wherein a cryogenic fluid is located in the neck tube, is characterized in that the neck tube is disposed between the outer shell and a cryocontainer and/or the radiation shield, the neck tube is closed in a gas-tight manner at the end facing the cryocontainer and/or the radiation shield, the neck tube is coupled to the cryocontainer and/or a radiation shield disposed between the cryocontainers or a cryocontainer and the outer shell, via a connection having a good thermal conductivity, the neck tube comprising a fill-in device at an end located at ambient temperature.

Abstract: A cryostat configuration for keeping liquid helium comprises an outer jacket (1) surrounding a helium container (2) connected at at least two suspension tubes (3) to the outer jacket (1), and with a neck tube (4) whose upper warm end (5) is connected to the outer jacket (1) and whose lower cold end (6) is connected to the helium container (2) and into which a multi-stage cold head of a cryocooler (7) is installed, wherein the outer jacket (1), the helium container (2), the suspension tubes (3) and the neck tube (4) delimit an evacuated space, and the helium container (2) is surrounded by at least one radiation shield (8) which is connected in a heat-conducting fashion to the suspension tubes (3) and also to a contact surface (9) on the neck tube (4) of the helium container (2).

Abstract: A magnet system with a magnet arrangement (M), a working volume (V) and a pulse tube cooler (P) with magnetic regenerator material (r) is characterized in that a shielding (m) of magnetic material is provided which reduces the stray field of the magnet arrangement at the location of the magnetic regenerator material (r) and is characterized in that ?|{tilde over (m)}RegR|+|mMag?x|<?|mRegR|, wherein mMag is the dipole moment of the magnetic material of the shielding (m), ?? is the vibration amplitude of the magnetic material of the shielding (m), mReg is the amplitude of the dipole fluctuations of the magnetic regenerator material (r) in one cycle without magnetic shielding (m), {tilde over (m)}Reg is the amplitude of the dipole fluctuations of the magnetic regenerator material (r) in one cycle with magnetic shielding (m), and R is the average separation of the magnetic regenerator material (r) from the working volume (V).

Abstract: A cryostat configuration for keeping liquid helium comprising an outer jacket (3) surrounding a helium container (1) connected at at least two suspension tubes (2) to the outer jacket (3), wherein the helium container (1) also comprises a neck tube (5) whose upper warm end is connected to the outer jacket (3) and whose lower cold end is connected to the helium container (1) and into which a multi-stage cold head (6) of a cryocooler is installed, wherein the outer jacket (3), the helium container (1), the suspension tubes (2) and the neck tube (5) delimit an evacuated space (7), and the helium container (1) is surrounded by at least one radiation shield (4) which is connected in a heat-conducting fashion to the suspension tubes (2) and also to the neck tube (5) of the helium container (1) is characterized in that there is a direct connection (8) between the warm ends of the suspension tubes (2) and the neck tube (5) through which helium gas can flow.

Abstract: A magnet system with a magnet arrangement (M), a working volume (V) and a pulse tube cooler (P) with magnetic regenerator material (r) is characterized in that a shielding (m) of magnetic material is provided which reduces the stray field of the magnet arrangement at the location of the magnetic regenerator material (r) and is characterized in that 1 3 ? ? m ~ Reg ? R ? + ? m Mag ? ? ? ? ? x ? < 1 6 ? ? m Reg ? R ? , wherein mMag is the dipole moment of the magnetic material of the shielding (m), ?? is the vibration amplitude of the magnetic material of the shielding (m), mReg is the amplitude of the dipole fluctuations of the magnetic regenerator material (r) in one cycle without magnetic shielding (m), {tilde over (m)}Reg is the amplitude of the dipole fluctuations of the magnetic regenerator material (r) in one cycle with magnetic shielding (m), and R is the average separation of the magnetic regenerator material (r) from the working volume (V).

Abstract: The invention relates to a material for electric contacts taking silver tin-oxide as basis, consisting of silver or mainly silver-containing alloy, tin oxide and other oxides or carbides of tungsten, molybdenum, vanadium, bismuth, titanium, and/or copper.