在碳硫联合测定中,以燃烧碘量法测定硫时,靠目测判别终点,误差较大。我们增加一只照度计(市售处理品“53型”),当光源透过硫的吸收管时,由于不同色泽深度所引起的不同光亮强度的变化,使照度计上的光电池产生微电位差,带动了照度计的指针。每次测定时,视指针 In the determination of carbon and sulfur in the joint, the determination of sulfur combustion iodine method, by visual determination of the end point, a larger error. We add a light meter (commercially available products “53 ”), when the light source through the sulfur absorption tube, due to the different color depth caused by the different brightness intensity changes, so that the light meter on the light meter micro Potential difference, led the meter pointer. Each measurement, depending on the pointer