ABSTRACT
Trace impurities of Al, Ca, Co, Fe, K, Mg, Mn, Na, Ni in silicon nitride powder were determined by slurry introduction into a solution-cathode glow discharge-atomic emission spectrometer (SCGD-AES).The effect of particle size on the stability of suspension was investigated.A 6-port valve was selected to link sampling system and SCGD-AES, by which the suspension could be introduced into the SCGD-AES to get instantaneous spectrum signal.The calibration curves for quantitative analysis could be established using aqueous standards and the pH of suspension was not required to be adjusted accurately.The applied voltage, solution flow rate, and integral time of PMT were set to 1080 V, 1.2 mL/min and 800 ms, respectively.In this work, slurry sampling was combined with SCGD-AES by a 6 port 2-pos valve.Powder Si3N4 was tested by this way and the limits of detection for all nine elements were 0.2-53.0 mg/kg.The RSDs were 1.1%-5.0%.The detection result of trace impurities in standard reference material ERM-ED101 agreed with that obtained from inductively coupled plasma atomic emission spectrometry.This method was proved to be accurate, reliable and valuable.
ABSTRACT
Laser ablation inductively coupled plasma mass spectrometry ( LA_ICP_MS ) was applied for the determination of doping element chromium( Cr) content and distribution in Cr∶ZnSe crystals. Several different Cr∶ZnSe crystals were prepared by diffusion method as reference material to solve the problem of accurate quantization. The homogeneity of Cr in these samples was characterized by LA_ICP_MS and the concentrations achieved by inductively coupled plasma atomic emission spectrometry ( ICP_AES ) . With signal pot and line scan sampling, the present method provided effective position and content distribution information of Cr in ZnSe crystals, achieved the in situ analysis. The correlation coefficient of Cr in calibration curve was 0. 9992 and the detection limit was 0. 08 mg/kg. It could provide effective means for the distribution statistics of doping element in different growth condition crystals.
ABSTRACT
TheLutetium-YttriumOrthosilicate(LYSO)isakindofscintillatingcrystalmaterialwiththebest comprehensive properties. In this work, the trace elements Ca, Fe, K, Li, Mg and Na in LYSO were determined by solution-cathode glow discharge-atomic emission spectrometry ( SCGS-AES ) . The optimal conditions included 0. 1 mol/L HNO3 sample solutions and operation at a voltage at 1080 V with a flow rate of 2. 0 mL/min. The LYSO matrix concentration tolerance of the SCGD source was determined to be 10 g/L. Sample solutions dissolving from several LYSO samples with HF, HNO3 and HClO4 were examined by SCGD-AES. For LYSO samples, the values obtained by SCGD-AES agree well with those obtained by axial inductively coupled plasma-atomic emission spectroscopy ( ICP-AES ) and inductively coupled plasma-mass spectroscopy (ICP-MS). The emissions of Lu and Y were not observed, so that the determination of trace elements in LYSO matrices could be conducted with little interference. The detection limits of Ca, Fe, K, Li, Mg and Na in LYSO were 1. 0, 3. 0, 0. 02, 0. 01, 0. 02 and 1. 0 mg/kg, respectively.