Hand-Held NIR Spectrometry: Part I: An Instrument Based upon Gap-Second Derivative Theory
Hand-Held NIR Spectrometry: Part I: An Instrument Based upon Gap-Second Derivative Theory
复制标题
手持式近红外光谱仪：第一部分：基于间隙二阶导数理论的仪器
DOI：
10.1366/0003702011951489
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发表时间：
2001
影响因子：
3.5
通讯作者：
D. L. Stanfield
中科院分区：
文献类型：
--
作者：
S. Morimoto;W. Mcclure;D. L. Stanfield
基于间隙二阶导数 (GSD) 理论设计、构建并测试了手持式近红外 (NIR) 测量仪（称为 Gmeter）。该设计采用窄带干涉滤光片来隔离 GSD 计算所需的三个波长。设计中包含微处理器，以方便独立和个人计算机 (PC) 操作。 Gmeter 安装在一个盒子中，用于在实验室内进行测量。 Gmeter 的性能与 FOSS NIRSystems 6500 型分光光度计的性能进行了比较，用于测量大豆蛋白/糖混合物中的蛋白质以及测量羊茅草组织中的氮。在两台仪器上开发了两种校准：(1) 单项 GSD 方程和 (2) 三项 (log 1/R) 多元线性回归 (MLR) 方程。 6500 型分光光度计上的二阶导数校准实验为选择 Gmeter 中的三个滤光片奠定了基础。 6500 型数据表明，GSD 校准 [变异系数 (CV) = 5.14%] 的性能优于三项 MLR 方程 (CV = 8.0%)。此外，使用单项 GSD 方程测量混合物中的蛋白质时，Gmeter 的表现几乎与 6500 型 (CV = 5.14%) 一样好 (CV = 6.30%)。这项研究中一个令人兴奋的额外事实是，为测定蛋白质/糖混合物中的蛋白质而选择的相同三个过滤器的测量结果可用于测定干草组织中的氮（CV = 17.2%）。
A hand-held near-infrared (NIR) meter (called the Gmeter), based upon gap-second derivative (GSD) theory, was designed, constructed, and performance-tested. The design incorporated narrow-band interference filters for isolating the three wavelengths required by the GSD calculations. A microprocessor was included in the design to facilitate both stand-alone and personal computer (PC) operation. The Gmeter was mounted in a caddy for making measurements within the laboratory. Performance of the Gmeter was compared with the performance of a FOSS NIRSystems Model 6500 spectrophotometer for measuring protein in soy-protein/sugar mixtures and for measuring nitrogen in fescue grass tissue. Two calibrations were developed on both instruments: (1) single-term GSD equations and (2) three-term (log 1/R) multiple linear regression (MLR) equations. Second-derivative calibration experiments on the Model 6500 spectrophotometer formulated the basis for selecting the three filters in the Gmeter. Model 6500 data indicated that the GSD calibration [coefficient of variation (CV) = 5.14%] performed better than a three-term MLR equation (CV = 8.0%). In addition, the Gmeter performed almost as well (CV = 6.30%) as the Model 6500 (CV = 5.14%) for measuring protein in the mixtures using single-term GSD equations. An exciting extra in this study was the fact that measurements from the same three filters selected for determining protein in protein/sugar mixtures could be used for determining nitrogen (CV = 17.2%) in dry-grass tissue.