Abstract: A cutting plotter includes a cutting plotter shell, a placement plate disposed outside the cutting plotter shell, an upper transmission assembly and a lower transmission assembly disposed at two ends of the cutting plotter shell, and a belt assembly disposed in the cutting plotter. The lower transmission assembly and the upper transmission assembly correspond to each other to assist paper in entering the cutting plotter. A slide rod is disposed in the cutting plotter shell and located at the top of the upper transmission assembly, and a cutting tool assembly is disposed on the slide rod. The belt assembly includes a driving motor. A belt body is steered through a steering belt wheel of the belt assembly, and the distance between parallel parts of the belt body is decreased through two small-radius tensioning belt wheels, such that the chain installation space is reduced and the cutting plotter is compact.

Abstract: Provided is a Raman spectroscopy method for simultaneously measuring a temperature and a thermal stress of a two-dimensional film material in situ. The method includes: providing the two-dimensional film material including a suspended part and a supported part and measuring Raman signals of the suspended part and the supported part; establishing equations of a Raman shift with temperature and a Raman shift with thermal stress for each of the suspended part and the supported part, and solving simultaneous equations to obtain coefficients with temperature and thermal stress; and scanning a characteristic Raman spectrum field of the two-dimensional film material and obtaining a temperature distribution and a thermal stress distribution of the two-dimensional film material according to the characteristic Raman spectrum field in combination of the coefficients of the Raman shift with temperature and the Raman shift with thermal stress.

Abstract: Provided is a Raman spectroscopy method for simultaneously measuring a temperature and a thermal stress of a two-dimensional film material in situ. The method includes: providing the two-dimensional film material including a suspended part and a supported part and measuring Raman signals of the suspended part and the supported part; establishing equations of a Raman shift with temperature and a Raman shift with thermal stress for each of the suspended part and the supported part, and solving simultaneous equations to obtain coefficients with temperature and thermal stress; and scanning a characteristic Raman spectrum field of the two-dimensional film material and obtaining a temperature distribution and a thermal stress distribution of the two-dimensional film material according to the characteristic Raman spectrum field in combination of the coefficients of the Raman shift with temperature and the Raman shift with thermal stress.

Abstract: An oil return method for multi-split air conditioner in heating comprises steps of: S1, adjusting operation frequency f0 of a compressor (11) to a first preset oil return frequency f1, and simultaneously, adjusting open degree S0 of each indoor throttling element (22) to a preset oil return open degree; S2, measuring operation parameters of the air conditioner; S3, judging whether the air conditioner operates abnormally, jumping to Step S4 if so, or jumping to Step S5 if not; S4, exiting from oil return process, adjusting the operation frequency f0 of the compressor (11) to a second preset oil return frequency f2, judging whether the air conditioner operates abnormally, existing from the oil return process if so, or jumping to Step S5 if not; S5, ending the oil return process when oil return time reaches the oil return time t2.

Abstract: An oil return method for multi-split air conditioner in heating comprises steps of: S1, adjusting operation frequency f0 of a compressor (11) to a first preset oil return frequency f1, and simultaneously, adjusting open degree S0 of each indoor throttling element (22) to a preset oil return open degree; S2, measuring operation parameters of the air conditioner; S3, judging whether the air conditioner operates abnormally, jumping to Step S4 if so, or jumping to Step S5 if not; S4, exiting from oil return process, adjusting the operation frequency f0 of the compressor (11) to a second preset oil return frequency f2, judging whether the air conditioner operates abnormally, existing from the oil return process if so, or jumping to Step S5 if not; S5, ending the oil return process when oil return time reaches the oil return time t2.