Abstract: This application provides a data transmission method and a communication apparatus. The method includes: A first device receives a trigger frame, where the trigger frame indicates a resource unit RU allocated to the first device; and the first device sends first data to a second device, where the first data occupies a discrete subcarrier in the RU. Based on the method provided by this application, a transmit power of a subcarrier can be increased, and transmission performance can be ensured.

Abstract: Disclosed are a GM type cryogenic refrigerator rotary valve and a preparation method therefor. The GM type cryogenic refrigerator rotary valve comprises an aluminum alloy rotating valve and an alumina ceramic membrane. A valve body of the aluminum alloy rotating valve is provided with a first surface for arranging a working boss and a second surface opposite to the first surface; and a high-pressure hole and a low-pressure groove are both provided in the working boss, and a vent hole is provided in the first surface; the high-pressure hole and the vent hole both penetrate the valve body, and an air chamber is formed on the second surface. The alumina ceramic membrane is plated on surface of the aluminum alloy rotating valve. The preparation method comprises: plating an alumina ceramic membrane on surface of an aluminum alloy rotating valve by means of a micro-arc oxidation process.

Abstract: Embodiments of the present disclosure provide a fastener for a server cabinet and the server cabinet. The fastener for the server cabinet includes an upper limit member, a fastening spring, a lower limit member, and a fastening pin rod. The present disclosure relates to the field of server cabinet technology. The fastener for the server cabinet provided in the present disclosure is small in volume, compact and reliable in structure, stable in fastening, and suitable for fastening connection in narrow space. The fastener may easily achieve fastening or unfastening operation by rotating 90° without restriction of a rotation direction, which is fast in installation and convenient for disassembly and assembly.

Abstract: A tunnel automatic monitoring and measuring equipment and method based on fixed-point tour measurement are provided. The equipment includes a monitoring trolley that can move freely in the longitudinal direction of the tunnel, multiple automatic tracking and identification devices are set on the monitoring trolley, the automatic tracking and identification device is connected to the background processing system telecommunication; a monitoring points with reflective markings are arranged on the surface of the tunnel support structure, under the cooperation of the monitoring trolley and the automatic tracking and identification device, the reflective markings set on the tunnel support structure can be automatically measured at the fixed point to obtain the coordinate information of the relevant monitoring points; then, the deformation data of the support structure required in the construction process are extracted by coordinate information calculation.

Abstract: A screening kit for paroxysmal supraventricular tachycardia contains a reagent for detecting a human CACNA1B gene c. 1700A>G mutation site at base No. 1700 in a coding region of CACNA1B gene from A to G.

Abstract: A screening kit for paroxysmal supraventricular tachycardia contains a reagent for detecting a human CACNA1B gene c. 1700A>G mutation site at base No. 1700 in a coding region of CACNA1B gene from A to G.