Abstract: A signal transmission cable is provided with a conductor, an insulator covering around the conductor, a shield layer covering around the insulator, a sheath covering around the shield layer, and a plating base layer is provided between the insulator and the shield layer to cover around the insulator. The shield layer has a plating layer provided to cover the plating base layer to be in contact with an outer peripheral surface of the plating base layer. A surface roughness of an outer peripheral surface of the plating layer is less than a surface roughness of an inner peripheral surface of the plating layer.

Abstract: The present invention provides a novel partial-pressure mass spectrometer calibration device, which is mainly composed of a fine adjustment valve, a piston pressure gauge, a sample preparation chamber, a plurality of high-purity gas cylinders, a capacitive film vacuum gauge, a first-stage sample inlet chamber, a second-stage sample inlet chamber, sampling chambers, a small hole, a calibration chamber, a separation gauge and air pumping systems, wherein the sample preparation chamber is connected with the piston pressure gauge and the capacitive film vacuum gauge; the sample preparation chamber is also connected with the plurality of high-purity gas cylinders which are connected in parallel via the fine adjustment valve; a plurality of sampling chambers with different volumes are connected in parallel between the sample preparation chamber and the first-stage sample inlet chamber; a plurality of sampling chambers with different volumes are connected in parallel between the first-stage sample inlet chamber and