Fig. 1From: Verifying the feasibility of using Hand-Held X-ray fluorescence spectrometer to analyze Linqing brick: evaluation of the influencing factors and assessing reliabilityRelationships between measurement time and RSD on precision for Fe, Ca, K, Al, Si, Ba, Zr, Mn, Mg, Ti, and Cl. The brick used was measured 5 times at 1 point for each measurement time. The RSD shown are calculated from these 5 replicates. Raw data shown in Additional file 1: Table S9Back to article page