Abstract: An automatic and rapid detection method of a gradation for an asphalt mixture and an automatic device are provided. The method includes: asphalt mixture introduction; asphalt mixture dehydration, including: heating the asphalt mixture and dehydrating to a target dehydration rate; asphalt combustion, including: burning the asphalt mixture by using a combustion method to form smoke to be removed, thereby obtaining aggregates, and obtaining an asphalt content; aggregate screening, including: grading through screening the aggregates according to different particle sizes by using a vibration screening device, and then weighing the aggregates, thereby obtaining weights of the aggregates; and obtaining the gradation, including: calculating the gradation for the asphalt mixture according to the weights of the aggregates with the different particle sizes and the asphalt content.

Abstract: The application provides a method for controlling nitrogen in steelmaking by spraying hydrogen containing plasma, including: using a mixture of hydrogen rich gas and argon gas to generate hydrogen plasma for denitrification of molten steel during at least one of arc furnace smelting, ladle refining, VOD refining, and RH refining. The method for controlling nitrogen in steelmaking by spraying hydrogen containing plasma provided in the application can effectively remove nitrogen from the molten steel by spraying a mixture of argon gas and hydrogen rich gas into the molten steel through a hollow electrode and plasma torch, reducing electrode consumption and electricity consumption per ton steel, and also reducing arc radiation heat loss, improving heating rate, thereby shortening smelting time and reducing production costs.

Abstract: A wafer cleaning apparatus provided by the present invention comprises a rotary shaft, a chuck arranged on the top of the rotary shaft for retaining the wafer, a fixed shaft coaxially passed through the rotary shaft, and an upper end cover and a lower end cover that block the top and bottom of the fixed shaft respectively. Wherein, the fixed shaft is a hollow shaft with at least one circle of exhaust holes provided on the wall of the fixed shaft. The lower end cover is arranged with a gas inlet port, through which a protective gas is provided to the interior of the fixed shaft. The protective gas forms a positive pressure in the annular space between the fixed shaft and the rotary shaft through the at least one circle of exhaust holes. The present invention provides positive pressure protective gas to the spacing between the fixed shaft and the rotary shaft by opening exhaust holes on the wall of the fixed shaft.

Abstract: The application provides a method for controlling nitrogen in steelmaking by spraying hydrogen containing plasma, including: using a mixture of hydrogen rich gas and argon gas to generate hydrogen plasma for denitrification of molten steel during at least one of arc furnace smelting, ladle refining, VOD refining, and RH refining. The method for controlling nitrogen in steelmaking by spraying hydrogen containing plasma provided in the application can effectively remove nitrogen from the molten steel by spraying a mixture of argon gas and hydrogen rich gas into the molten steel through a hollow electrode and plasma torch, reducing electrode consumption and electricity consumption per ton steel, and also reducing arc radiation heat loss, improving heating rate, thereby shortening smelting time and reducing production costs.

Abstract: A client server load testing system provides a software and hardware infrastructure facilitating the use of an engine that generates a plurality of virtual clients or virtual users. These virtual users are provided with scenarios representing an online user session with the server under test by the action of a message building agent that populates the scenario with test data.