Abstract: The invention relates to a miniaturized gas chromatography module, comprising: a gas injector unit having a gas injector sample inlet and outlet, the gas injector inlet being connectable with a source of a substance to be analyzed, a separation column having a separation column inlet and outlet, the separation column inlet being in fluid communication with the gas injector sample outlet, a thermal conductivity sensor having a sensor inlet and outlet, the sensor inlet being in fluid communication with the separation column outlet. The invention addresses the problem to broaden the field of application of such gas chromatography module. This is achieved by providing a pre-stage injector having a pre-stage injector sample inlet and outlet, the pre-stage injector sample inlet being connectable with the source of the substance to be analyzed, a pre-stage module having a module inlet and outlet, the module inlet being in fluid communication with the pre-stage injector sample.

Abstract: The invention relates to a miniaturized gas chromatography module, comprising: a gas injector unit having a gas injector sample inlet and outlet, the gas injector inlet being connectable with a source of a substance to be analysed, a separation column having a separation column inlet and outlet, the separation column inlet being in fluid communication with the gas injector sample outlet, a thermal conductivity sensor having a sensor inlet and outlet, the sensor inlet being in fluid communication with the separation column outlet. The invention addresses the problem to broaden the field of application of such gas chromatography module.

Abstract: A ball-game racket, particularly a tennis racket, including a hollow, outdly closed racket body that forms a racket handle and a racket frame including a racket head, the racket frame being provided with stringing formed of intersecting string lengths on the racket head and defining a stringing plane, at least part of the string lengths having on the inside of the frame, at least in an axial direction perpendicular to the stringing plane, a mobility greater than the corresponding mobility of the outer side of the racket frame.

Abstract: A tennis racket includes a handle portion, a frame portion which has strings mounted therein and a throat portion which connects the handle portion and the frame portion. An insert is installed in the throat portion and connected to the same. The insert is adapted to have secured thereto at least some of the strings. The insert may undergo elastic yielding in direction substantially normal to the general plane of the frame portion in response to the impact of a ball onto the strings and consequent transmission of the impact stress from the strings to the insert.