摘要:
The use of surfactants that do not themselves act as dopants and are isoelectronic with either the group III or group V host atoms during OMVPE growth significantly reduces the incorporation of background impurities such as carbon, oxygen, sulfur and/or silicon. For example, the use of the surfactants Sb or Bi significantly reduces the incorporation of background impurities such as carbon, oxygen, sulfur and/or silicon during the OMVPE growth of III/V semiconductor materials, for example GaAs, GaInP, and GaP layers. As a result, an effective method for controlling the incorporation of impurity atoms is adding a minute amount of surfactant during OMVPE growth.
摘要:
The invention relates to a tube coupling (TC2) for connecting an object (22) to one end of a tube (20) in a UHV tight manner, withstanding pressures up to several hundred bars and accommodating temperature differences from heating or cooling, said tube coupling (TC2) comprising said tube (20) and a tube fitting (10), wherein said tube fitting (10) comprises a basically cylindrical body (11) with a first central bore for receiving said tube (20), such that said tube (20) is axially supported by a radially extending shoulder (18) at the inner end of said first central bore, and wherein said tube (20) is pressed with its end face against said radially extending shoulder (18) by means of a gripping arrangement (13, 14, 15). The vacuum capability is achieved with simple components by providing a gasket (21) between said end face of said tube (20) and said radially extending shoulder (18) at the inner end of said first central bore (16).
摘要:
A brake includes a brake shoe moveable between an engaged position and a disengaged position and defining an axis of rotation of an associated brake drum. The brake includes an actuation shaft rotatable about a shaft axis and an actuation device for transferring rotational movement of the actuation shaft into movement of the brake shoe from the disengaged position to the engaged position. The axis of rotation is non-parallel to the shaft axis.
摘要:
A method for obtaining information about an unknown neutron source or an unknown material interacting with a known neutron source comprises the steps of: (a) providing a radiation detector capable of delivering a neutron energy information allowing the production of response histogram(s) as a function of neutron energy, (b) measuring with said radiation detector neutrons being emitted from said unknown neutron source or from said unknown material, (c) deriving from said measured neutrons a neutron energy spectrum, especially in form of a histogram, (d) normalizing said energy spectrum or histogram relative to a parameter or set of parameters derived from the measurement of a different variable, (e) comparing said normalized energy spectrum or histogram with known energy spectra or histograms, and (f) drawing conclusions on the basis of said comparison about the nature of the unknown neutron source or unknown material.
摘要:
A method for obtaining information about an unknown neutron source or an unknown material interacting with a known neutron source comprises the steps of: (a) providing a radiation detector capable of delivering a neutron energy information allowing the production of response histogram(s) as a function of neutron energy, (b) measuring with said radiation detector neutrons being emitted from said unknown neutron source or from said unknown material, (c) deriving from said measured neutrons a neutron energy spectrum, especially in form of a histogram, (d) normalizing said energy spectrum or histogram relative to a parameter or set of parameters derived from the measurement of a different variable, (e) comparing said normalized energy spectrum or histogram with known energy spectra or histograms, and (f) drawing conclusions on the basis of said comparison about the nature of the unknown neutron source or unknown material.
摘要:
A brake includes a brake shoe moveable between an engaged position and a disengaged position and defining an axis of rotation of an associated brake drum. The brake includes an actuation shaft rotatable about a shaft axis and an actuation device for transferring rotational movement of the actuation shaft into movement of the brake shoe from the disengaged position to the engaged position. The axis of rotation is non-parallel to the shaft axis.