The Experts below are selected from a list of 17739 Experts worldwide ranked by ideXlab platform
S. C. Sharma - One of the best experts on this subject based on the ideXlab platform.
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wear characteristics of sub zero chilled cast iron
Wear, 1996Co-Authors: K H W Seah, Joel Hemanth, S. C. SharmaAbstract:This paper presents the results obtained and the deductions made from a series of wear tests involving sub-zero chilled (using liquid nitrogen) cast iron containing 1.5% Cu, and Chromium Contents ranging from 0.0% to 0.2%. By using copper chills of different thicknesses, the effect of wear resistance of varying the chill rate was also examined. The wear tests were carried out using a modified pin-on-disk method. It was found that wear resistance is highly dependent on the Chromium Content of the material, as well as the rate of chill. Moreover, wear resistance also increases monotonically with hardness and tensile strength.
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corrosion behaviour of sub zero chilled cast iron
Materials & Design, 1994Co-Authors: K H W Seah, Joel Hemanth, S. C. SharmaAbstract:Abstract This paper describes the results obtained and the deductions made from a series of corrosion experiments involving sub-zero chilled (using liquid nitrogen) cast iron containing 1.5% Cu and of Chromium Contents ranging from 0.0% to 0.2%. By using copper chills of different thicknesses the effect on corrosion of varying the chill rate was also examined. The corrosion tests employed were the weight-loss method according to ASTM G 67–80 standards. The microstructures of the corrosion products were also examined. Corrosion resistance was found to increase significantly with increase in Chromium Content. Nevertheless, even with high Chromium Content, some pitting was detected in the initial stages of most of the tests. Generally, corrosion attack was found to be most severe during the initial stage of each test but it invariably decreased to a very low value in the later stages, probably due to the formation of an adherent protective layer on the metal surface.
Fei Liu - One of the best experts on this subject based on the ideXlab platform.
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High-accuracy and fast determination of Chromium Content in rice leaves based on collinear dual-pulse laser-induced breakdown spectroscopy and chemometric methods.
Food chemistry, 2019Co-Authors: Peng Jiyu, Fei Zhou, Jiandong Jiang, Zhangfeng Zhao, Fei LiuAbstract:Dual-pulse laser-induced breakdown spectroscopy (DPLIBS) and chemometric methods were used to predict Chromium Content in rice leaves, along with the purpose for increasing the detection sensitivity and accuracy. The influence of important parameters in DPLIBS were investigated and optimized. Then, partial least square (PLS) was used to establish Chromium Content prediction models, and the value of regression coefficient based on PLS was applied to determine feature variables. In addition, multivariate and univariate analysis were used to verify the modeling performance of selected feature variables. The results indicated that support vector machine model based on feature variables achieved the best performance, with correlation coefficient of 0.9946, root mean square error of 4.85 mg/kg and residual predictive deviation of 9.70 in prediction set. The proposed method provides a high-accuracy and fast approach for Chromium Content prediction in rice leaves, which could potentially be used for toxic and nutrient elements detection in food.
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comparative study of the detection of Chromium Content in rice leaves by 532 nm and 1064 nm laser induced breakdown spectroscopy
Sensors, 2018Co-Authors: Jiyu Peng, Fei Liu, Tingting Shen, Wenwen Kong, Wei Wang, Xiaodan LiuAbstract:Fast detection of toxic metals in crops is important for monitoring pollution and ensuring food safety. In this study, laser-induced breakdown spectroscopy (LIBS) was used to detect the Chromium Content in rice leaves. We investigated the influence of laser wavelength (532 nm and 1064 nm excitation), along with the variations of delay time, pulse energy, and lens-to-sample distance (LTSD), on the signal (sensitivity and stability) and plasma features (temperature and electron density). With the optimized experimental parameters, univariate analysis was used for quantifying the Chromium Content, and several preprocessing methods (including background normalization, area normalization, multiplicative scatter correction (MSC) transformation and standardized normal variate (SNV) transformation were used to further improve the analytical performance. The results indicated that 532 nm excitation showed better sensitivity than 1064 nm excitation, with a detection limit around two times lower. However, the prediction accuracy for both excitation wavelengths was similar. The best result, with a correlation coefficient of 0.9849, root-mean-square error of 3.89 mg/kg and detection limit of 2.72 mg/kg, was obtained using the SNV transformed signal (Cr I 425.43 nm) induced by 532 nm excitation. The results indicate the inspiring capability of LIBS for toxic metals detection in plant materials.
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moisture influence reducing method for heavy metals detection in plant materials using laser induced breakdown spectroscopy a case study for Chromium Content detection in rice leaves
Analytical Chemistry, 2017Co-Authors: Jiyu Peng, Fei Liu, Tingting Shen, Wenwen Kong, Xiaodan Liu, Yun ZhaoAbstract:Fast detection of heavy metals in plant materials is crucial for environmental remediation and ensuring food safety. However, most plant materials contain high moisture Content, the influence of which cannot be simply ignored. Hence, we proposed moisture influence reducing method for fast detection of heavy metals using laser-induced breakdown spectroscopy (LIBS). First, we investigated the effect of moisture Content on signal intensity, stability, and plasma parameters (temperature and electron density) and determined the main influential factors (experimental parameters F and the change of analyte concentration) on the variations of signal. For Chromium Content detection, the rice leaves were performed with a quick drying procedure, and two strategies were further used to reduce the effect of moisture Content and shot-to-shot fluctuation. An exponential model based on the intensity of background was used to correct the actual element concentration in analyte. Also, the ratio of signal-to-background for ...
K H W Seah - One of the best experts on this subject based on the ideXlab platform.
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wear characteristics of sub zero chilled cast iron
Wear, 1996Co-Authors: K H W Seah, Joel Hemanth, S. C. SharmaAbstract:This paper presents the results obtained and the deductions made from a series of wear tests involving sub-zero chilled (using liquid nitrogen) cast iron containing 1.5% Cu, and Chromium Contents ranging from 0.0% to 0.2%. By using copper chills of different thicknesses, the effect of wear resistance of varying the chill rate was also examined. The wear tests were carried out using a modified pin-on-disk method. It was found that wear resistance is highly dependent on the Chromium Content of the material, as well as the rate of chill. Moreover, wear resistance also increases monotonically with hardness and tensile strength.
-
corrosion behaviour of sub zero chilled cast iron
Materials & Design, 1994Co-Authors: K H W Seah, Joel Hemanth, S. C. SharmaAbstract:Abstract This paper describes the results obtained and the deductions made from a series of corrosion experiments involving sub-zero chilled (using liquid nitrogen) cast iron containing 1.5% Cu and of Chromium Contents ranging from 0.0% to 0.2%. By using copper chills of different thicknesses the effect on corrosion of varying the chill rate was also examined. The corrosion tests employed were the weight-loss method according to ASTM G 67–80 standards. The microstructures of the corrosion products were also examined. Corrosion resistance was found to increase significantly with increase in Chromium Content. Nevertheless, even with high Chromium Content, some pitting was detected in the initial stages of most of the tests. Generally, corrosion attack was found to be most severe during the initial stage of each test but it invariably decreased to a very low value in the later stages, probably due to the formation of an adherent protective layer on the metal surface.
Michael Krumpelt - One of the best experts on this subject based on the ideXlab platform.
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corrosion behavior and interfacial resistivity of bipolar plate materials under molten carbonate fuel cell cathode conditions
Journal of The Electrochemical Society, 2000Co-Authors: Annett C Schoeler, Michael Lanagan, Ira Bloom, Thomas D. Kaun, Michael KrumpeltAbstract:A material is needed for bipolar plate materials in molten carbonate fuel cells (MCFCs) that combines the low oxide resistivity of 316L stainless steel (SS) with the low corrosion rate of the type 310 SS. We tested a group of materials that included Nitronic 50 SS and a newly developed high-temperature nickel-rich alloy, having Chromium Contents ranging from 16 to 31 wt %. Our results indicate that Chromium Content is the primary determinant of oxide scale composition and resistivity. In the MCFC cathode compartment, all tested alloys formed a duplex structure with an inner Cr-rich layer and an outer Fe-rich one. The composition of the inner Cr-rich layer was determined by the Chromium Content of the base alloy and has a controlling effect on scale resistivity. Oxide scale resistivity was measured for three electrolyte compositions: Li/K, Li/Na, and newly developed (Li, Na, Ca, Ba) carbonates. Changes in the physical/mechanical properties (spallation/cracking) in the oxide scale of 316L SS provided an understanding of its resistivity fluctuations over time.
Xiaodan Liu - One of the best experts on this subject based on the ideXlab platform.
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comparative study of the detection of Chromium Content in rice leaves by 532 nm and 1064 nm laser induced breakdown spectroscopy
Sensors, 2018Co-Authors: Jiyu Peng, Fei Liu, Tingting Shen, Wenwen Kong, Wei Wang, Xiaodan LiuAbstract:Fast detection of toxic metals in crops is important for monitoring pollution and ensuring food safety. In this study, laser-induced breakdown spectroscopy (LIBS) was used to detect the Chromium Content in rice leaves. We investigated the influence of laser wavelength (532 nm and 1064 nm excitation), along with the variations of delay time, pulse energy, and lens-to-sample distance (LTSD), on the signal (sensitivity and stability) and plasma features (temperature and electron density). With the optimized experimental parameters, univariate analysis was used for quantifying the Chromium Content, and several preprocessing methods (including background normalization, area normalization, multiplicative scatter correction (MSC) transformation and standardized normal variate (SNV) transformation were used to further improve the analytical performance. The results indicated that 532 nm excitation showed better sensitivity than 1064 nm excitation, with a detection limit around two times lower. However, the prediction accuracy for both excitation wavelengths was similar. The best result, with a correlation coefficient of 0.9849, root-mean-square error of 3.89 mg/kg and detection limit of 2.72 mg/kg, was obtained using the SNV transformed signal (Cr I 425.43 nm) induced by 532 nm excitation. The results indicate the inspiring capability of LIBS for toxic metals detection in plant materials.
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moisture influence reducing method for heavy metals detection in plant materials using laser induced breakdown spectroscopy a case study for Chromium Content detection in rice leaves
Analytical Chemistry, 2017Co-Authors: Jiyu Peng, Fei Liu, Tingting Shen, Wenwen Kong, Xiaodan Liu, Yun ZhaoAbstract:Fast detection of heavy metals in plant materials is crucial for environmental remediation and ensuring food safety. However, most plant materials contain high moisture Content, the influence of which cannot be simply ignored. Hence, we proposed moisture influence reducing method for fast detection of heavy metals using laser-induced breakdown spectroscopy (LIBS). First, we investigated the effect of moisture Content on signal intensity, stability, and plasma parameters (temperature and electron density) and determined the main influential factors (experimental parameters F and the change of analyte concentration) on the variations of signal. For Chromium Content detection, the rice leaves were performed with a quick drying procedure, and two strategies were further used to reduce the effect of moisture Content and shot-to-shot fluctuation. An exponential model based on the intensity of background was used to correct the actual element concentration in analyte. Also, the ratio of signal-to-background for ...