Establishment of ambient air by graphite furnace atomic method for the determination of trace tin absorption method. Mixed cellulose microporous membrane collecting ambient air samples with nitric acid - hydrofluoric acid microwave digestion with 5% -10% lanthanum nitrate mixture of tartaric acid as matrix modifier, graphite furnace atomic absorption spectrometry measurement. When the sample size is 4800 L, constant volume when the volume of 50 mL, the detection limit was 0.024μg / m3, the sample recovery was 96.0% and 106.0%, the relative standard deviation of the measurement results is 2.74% ~ 5.81% (n = 7). The method of sample preparation procedure is simple, with less acid, can be used for the determination of trace tin in ambient air.

Ultra-thin display technology has become a major trend of the market. In this paper, cleaning after etching technology of the intermittent display of semi-finished chemical thinning. In the photoresist and border protection glue, adjusting the concentration of hydrofluoric acid, adding a certain amount of nitric acid, concentrated sulfuric acid and hydrochloric acid, and add the ultrasound-assisted conditions, the etching rate has improved significantly. By alternating the cleaning process effectively reduce the surface roughness, and reducing the surface precipitated white deposit. Panel thickness from 0.8mm thinned to 0.3mm, the surface roughness of the substrate 11.32nm, thickness uniformity of 4.76%. Design intermittent thinning process can be applied to existing monitor the production process for the production of ultra-thin and ultra-thin organic light-emitting LCD provides a viable option display.