The near infrared （NIR） spectroscopy technique has been applied in many fields because of its advantages of simple preparation, fast response, and non-destructiveness. We investigated the potential of NIR spectrosco...The near infrared （NIR） spectroscopy technique has been applied in many fields because of its advantages of simple preparation, fast response, and non-destructiveness. We investigated the potential of NIR spectroscopy in diffuse reflectance mode for determining the soluble solid content （SSC） and acidity （pH） of intact loquats. Two cultivars of loquats （Dahongpao and Jiajiaozhong） harvested from two orchards （Tangxi and Chun＇an, Zhejiang, China） were used for the measurement of NIR spectra between 800 and 2500 nm. A total of 400 loquats （100 samples of each cultivar from each orchard） were used in this study. Relationships between NIR spectra and SSC and acidity of loquats were evaluated using partial least square （PLS） method. Spectra preprocessing options included the first and second derivatives, multiple scatter correction （MSC）, and the standard normal variate （SNV）. Three separate spectral windows identified as full NIR （800-2500 nm）, short NIR （800-1100 rim）, and long NIR （1100-2500 nm） were studied in factorial combination with the preprocessing options. The models gave relatively good predictions of the SSC of loquats, with root mean square error of prediction （RMSEP） values of 1.21, 1.00, 0.965, and 1.16 °Brix for Tangxi-Dahongpao, Tangxi-Jiajiaozhong, Chun＇an-Dahongpao, and Chun＇an-Jiajiaozhong, respectively. The acidity prediction was not satisfactory, with the RMSEP of 0.382, 0.194, 0.388, and 0.361 for the above four loquats, respectively. The results indicate that NIR diffuse reflectance spectroscopy can be used to predict the SSC and acidity of loquat fruit.展开更多
The formation of secondary Ln（III） solid phases （e.g., Nd2（CO3）3 and Sm2（CO3）3） was studied as a function of the humic acid concentration in 0.1 mol/L NaClO4 aqueous solution in the neutral pH range （5–6.5）...The formation of secondary Ln（III） solid phases （e.g., Nd2（CO3）3 and Sm2（CO3）3） was studied as a function of the humic acid concentration in 0.1 mol/L NaClO4 aqueous solution in the neutral pH range （5–6.5）. The solid phases under investigation were prepared by alkaline precipitation under 100% CO2 atmosphere and characterized by attenuated total reflectance Fourier transform infrared spectroscopy （ATR-FTIR）, X-ray diffraction （XRD）, time-resolved laser fluorescence spectroscopy （TRLFS）, diffuse reflectance ultraviolet-visible （DR-UV-Vis）, Raman spectroscopy, and solubility measurements. The spectroscopic data obtained indicated that Nd2（CO3）3 and Sm2（CO3）3 were stable and remained the solubility limiting solid phases even in the presence of increased humic acid concentration （0.5 g/L） in solution. Upon base addition in the Ln（III）-HA system, decomplexation of the previously formed Ln（III）-humate complexes and precipitation of two distinct phases occurred, the inorganic （Ln2（CO3）3） and the organic phase （HA）, which was adsorbed on the particle surface of the former. Nevertheless, humic acid affected the particle size of the solid phases. Increasing humic acid concentration resulted in decreasing crystallite size of the Nd2（CO3）3 and increasing crystallite size of the Sm2（CO3）3 solid phase, and affected inversely the solubility of the solid phases. However, this impact on the solid phase properties was expected to be of minor relevance regarding the chemical behavior and migration of trivalent lanthanides and actinides in the geosphere.展开更多
基金Project supported by the National Natural Science Foundation of China(No.30825027)the National Key Technology R&D Program of China(No.2006BAD11A12)
文摘The near infrared （NIR） spectroscopy technique has been applied in many fields because of its advantages of simple preparation, fast response, and non-destructiveness. We investigated the potential of NIR spectroscopy in diffuse reflectance mode for determining the soluble solid content （SSC） and acidity （pH） of intact loquats. Two cultivars of loquats （Dahongpao and Jiajiaozhong） harvested from two orchards （Tangxi and Chun＇an, Zhejiang, China） were used for the measurement of NIR spectra between 800 and 2500 nm. A total of 400 loquats （100 samples of each cultivar from each orchard） were used in this study. Relationships between NIR spectra and SSC and acidity of loquats were evaluated using partial least square （PLS） method. Spectra preprocessing options included the first and second derivatives, multiple scatter correction （MSC）, and the standard normal variate （SNV）. Three separate spectral windows identified as full NIR （800-2500 nm）, short NIR （800-1100 rim）, and long NIR （1100-2500 nm） were studied in factorial combination with the preprocessing options. The models gave relatively good predictions of the SSC of loquats, with root mean square error of prediction （RMSEP） values of 1.21, 1.00, 0.965, and 1.16 °Brix for Tangxi-Dahongpao, Tangxi-Jiajiaozhong, Chun＇an-Dahongpao, and Chun＇an-Jiajiaozhong, respectively. The acidity prediction was not satisfactory, with the RMSEP of 0.382, 0.194, 0.388, and 0.361 for the above four loquats, respectively. The results indicate that NIR diffuse reflectance spectroscopy can be used to predict the SSC and acidity of loquat fruit.
基金Project supported by the Cyprus Research Promotion Foundation (ΠΕΝΕΚ/ΕΝΙΣΧ/0308/05 and ΠΡΟΣΒΑΣΗ/ΕΡΥΕΞ/0308/02)
文摘The formation of secondary Ln（III） solid phases （e.g., Nd2（CO3）3 and Sm2（CO3）3） was studied as a function of the humic acid concentration in 0.1 mol/L NaClO4 aqueous solution in the neutral pH range （5–6.5）. The solid phases under investigation were prepared by alkaline precipitation under 100% CO2 atmosphere and characterized by attenuated total reflectance Fourier transform infrared spectroscopy （ATR-FTIR）, X-ray diffraction （XRD）, time-resolved laser fluorescence spectroscopy （TRLFS）, diffuse reflectance ultraviolet-visible （DR-UV-Vis）, Raman spectroscopy, and solubility measurements. The spectroscopic data obtained indicated that Nd2（CO3）3 and Sm2（CO3）3 were stable and remained the solubility limiting solid phases even in the presence of increased humic acid concentration （0.5 g/L） in solution. Upon base addition in the Ln（III）-HA system, decomplexation of the previously formed Ln（III）-humate complexes and precipitation of two distinct phases occurred, the inorganic （Ln2（CO3）3） and the organic phase （HA）, which was adsorbed on the particle surface of the former. Nevertheless, humic acid affected the particle size of the solid phases. Increasing humic acid concentration resulted in decreasing crystallite size of the Nd2（CO3）3 and increasing crystallite size of the Sm2（CO3）3 solid phase, and affected inversely the solubility of the solid phases. However, this impact on the solid phase properties was expected to be of minor relevance regarding the chemical behavior and migration of trivalent lanthanides and actinides in the geosphere.
