Corrections for wind tunnel experimental results are crucial when accounting for tun-nel wall interference.This study introduces a new method,the non-uniform wall pres-sure signature method(NUWPSM),which is designed t...Corrections for wind tunnel experimental results are crucial when accounting for tun-nel wall interference.This study introduces a new method,the non-uniform wall pres-sure signature method(NUWPSM),which is designed to address tunnel wall interfer-ence in airfoil.The improved wall pressure signature method(WPSM),an enhanced version of the WPSM,is developed to address the velocity disparities and systematic errors in pressure measurements between with and without model conditions.Fur-thermore,the NUWPSM considers the non-uniformity of the flow induced by the lim-ited far-field effect in wind tunnel experiments.Utilizing experimental data from three different scaled models of the WA210 airfoil,the efficacy of both the Improved WPSM and NUWPSM is verified.Results indicate that the Improved WPSM exhibits superior capabilities in simulating the distribution of axial induced velocity along the wall com-pared to the traditional WPSM.Additionally,both the Improved WPSM and NUWPSM demonstrate comparable abilities in correcting tunnel wall interference,achiev-ing precise corrections within an angle of attack range of-180°to+180°.Notably,the NUWPSM effectively captures the velocity non-uniformity induced by the limited far-field effect,thereby extending its applicability to a broader range of scenarios.Furthermore,the NUWPSM showcases enhanced robustness by eliminating human intervention in the singularity quantity and distribution.展开更多
A Kalman filter was developed for correction of wing interference in ICP-AES.Modeling wing interference theoretically instead of experimentally, the filter can compensate the shift in wavelength position in scans, and...A Kalman filter was developed for correction of wing interference in ICP-AES.Modeling wing interference theoretically instead of experimentally, the filter can compensate the shift in wavelength position in scans, and therefore reduce the effect of the interference on detection limit.展开更多
In the determination of trace yttrium (Y) in an ytterbium (Yb) matrix byinductively coupled plasma atomic emission spectrometry (ICP-AES), the most prominent line ofyttrium, Y 371.030 nm line, suffers from strong inte...In the determination of trace yttrium (Y) in an ytterbium (Yb) matrix byinductively coupled plasma atomic emission spectrometry (ICP-AES), the most prominent line ofyttrium, Y 371.030 nm line, suffers from strong interference due to an emission line of ytterbium.In mis work, a method based on wavelet transform was proposed for the spectral interferencecorrection. Haar wavelet was selected as the mother wavelet. The discrete detail after the thirddecomposition, D3, was chosen for quantitative analysis based on the consideration of bothseparation degree and peak height. The linear correlation coefficient between the height of the leftpositive peak in D3 and the concentration of Y was calculated to be 0.9926. Six synthetic sampleswere analyzed, and the recovery for yttrium varied from 96.3 percent to 110.0 percent. The amountsof yttrium in three ytterbium metal samples were determined by the proposed approach with an averagerelative standard deviation (RSD) of 2.5 percent, and the detection limit for yttrium was 0.016percent. This novel correction technique is fast and convenient, since neither complicated modelassumption nor time-consuming iteration is required. Furthermore, it is not affected by thewavelength drift inherent in monochromators that will severely reduce the accuracy of resultsobtained by some chemometric methods.展开更多
Inductively coupled plasma mass spectrometry （ICP-MS） is the most commonly used technique to deter- mine the abundances of trace elements in a wide range of geological materials. However, incomplete sample digestion...Inductively coupled plasma mass spectrometry （ICP-MS） is the most commonly used technique to deter- mine the abundances of trace elements in a wide range of geological materials. However, incomplete sample digestion, isobaric interferences and instrumental drift remain obvious problems that must be overcome in order to obtain precise and accurate results, For this reason, we have done many experi- ments and developed a set of simple, cost-effective and practical methods widely applicable for precise and rapid determination of trace element abundances in geological materials using ICP-MS. Commonly used high-pressure digestion technique is indeed effective in decomposing refractory phases, but this inevitably produces fluoride complexes that create new problems. We demonstrate that the fluoride complexes formed during high-pressure digestion can be readily re-dissolved using high-pressure vessel at 190 ℃ for only 2 h for 50 mg sample. In the case of isobaric interferences, although oxide （e.g., MO^＋/M^＋） and hydroxide （e.g., MO^＋/M^＋） productivity is variable between runs, the （MO^＋/M^＋）/（CeO^＋/Ce^＋） and （MOH^＋/M^＋）/（CeO^＋/Ce^＋） ratios remain constant, making isobaric interference correction for all other elements of interest straightforward, for which we provide an easy-to-use off-line procedure. We also show that mass-time-intensity drift curve is smooth as recognized previously, for which the correction can be readily done by analyzing a quality-control （QC） solution and using off-line Excel VBA procedure without internal standards. With these methods, we can produce data in reasonable agreement with rec- ommended values of international rock reference standards with a relative error of 〈8% and precision generally better than 5%. Importantly, compared to the widely used analytical practice, we can effectively save 〉60% of time （e.g., 〈24 h vs. 〉60 h）.展开更多
基金This work was sponsored by the National Natural Science Foundation of China(No.12302303)the China Postdoctoral Science Foundation(No.2023M732777)+1 种基金the foundation of National Key Laboratory of Aircraft Configuration Design(No.ZYTS-202403)the foundation of National Key Laboratory of Science and Technology on Aerodynamic Design and Research(No.2023-JCJQ-LB-070).
文摘Corrections for wind tunnel experimental results are crucial when accounting for tun-nel wall interference.This study introduces a new method,the non-uniform wall pres-sure signature method(NUWPSM),which is designed to address tunnel wall interfer-ence in airfoil.The improved wall pressure signature method(WPSM),an enhanced version of the WPSM,is developed to address the velocity disparities and systematic errors in pressure measurements between with and without model conditions.Fur-thermore,the NUWPSM considers the non-uniformity of the flow induced by the lim-ited far-field effect in wind tunnel experiments.Utilizing experimental data from three different scaled models of the WA210 airfoil,the efficacy of both the Improved WPSM and NUWPSM is verified.Results indicate that the Improved WPSM exhibits superior capabilities in simulating the distribution of axial induced velocity along the wall com-pared to the traditional WPSM.Additionally,both the Improved WPSM and NUWPSM demonstrate comparable abilities in correcting tunnel wall interference,achiev-ing precise corrections within an angle of attack range of-180°to+180°.Notably,the NUWPSM effectively captures the velocity non-uniformity induced by the limited far-field effect,thereby extending its applicability to a broader range of scenarios.Furthermore,the NUWPSM showcases enhanced robustness by eliminating human intervention in the singularity quantity and distribution.
文摘A Kalman filter was developed for correction of wing interference in ICP-AES.Modeling wing interference theoretically instead of experimentally, the filter can compensate the shift in wavelength position in scans, and therefore reduce the effect of the interference on detection limit.
文摘In the determination of trace yttrium (Y) in an ytterbium (Yb) matrix byinductively coupled plasma atomic emission spectrometry (ICP-AES), the most prominent line ofyttrium, Y 371.030 nm line, suffers from strong interference due to an emission line of ytterbium.In mis work, a method based on wavelet transform was proposed for the spectral interferencecorrection. Haar wavelet was selected as the mother wavelet. The discrete detail after the thirddecomposition, D3, was chosen for quantitative analysis based on the consideration of bothseparation degree and peak height. The linear correlation coefficient between the height of the leftpositive peak in D3 and the concentration of Y was calculated to be 0.9926. Six synthetic sampleswere analyzed, and the recovery for yttrium varied from 96.3 percent to 110.0 percent. The amountsof yttrium in three ytterbium metal samples were determined by the proposed approach with an averagerelative standard deviation (RSD) of 2.5 percent, and the detection limit for yttrium was 0.016percent. This novel correction technique is fast and convenient, since neither complicated modelassumption nor time-consuming iteration is required. Furthermore, it is not affected by thewavelength drift inherent in monochromators that will severely reduce the accuracy of resultsobtained by some chemometric methods.
基金supported by National Natural Science Foundation of China(41130314 and 41630968)Chinese Academy of Sciences Innovation Grant(Y42217101L)+1 种基金Qingdao National Laboratory for Marine Science and Technology(2015ASKJ03)Marine Geological Process and Environment(U1606401)
文摘Inductively coupled plasma mass spectrometry （ICP-MS） is the most commonly used technique to deter- mine the abundances of trace elements in a wide range of geological materials. However, incomplete sample digestion, isobaric interferences and instrumental drift remain obvious problems that must be overcome in order to obtain precise and accurate results, For this reason, we have done many experi- ments and developed a set of simple, cost-effective and practical methods widely applicable for precise and rapid determination of trace element abundances in geological materials using ICP-MS. Commonly used high-pressure digestion technique is indeed effective in decomposing refractory phases, but this inevitably produces fluoride complexes that create new problems. We demonstrate that the fluoride complexes formed during high-pressure digestion can be readily re-dissolved using high-pressure vessel at 190 ℃ for only 2 h for 50 mg sample. In the case of isobaric interferences, although oxide （e.g., MO^＋/M^＋） and hydroxide （e.g., MO^＋/M^＋） productivity is variable between runs, the （MO^＋/M^＋）/（CeO^＋/Ce^＋） and （MOH^＋/M^＋）/（CeO^＋/Ce^＋） ratios remain constant, making isobaric interference correction for all other elements of interest straightforward, for which we provide an easy-to-use off-line procedure. We also show that mass-time-intensity drift curve is smooth as recognized previously, for which the correction can be readily done by analyzing a quality-control （QC） solution and using off-line Excel VBA procedure without internal standards. With these methods, we can produce data in reasonable agreement with rec- ommended values of international rock reference standards with a relative error of 〈8% and precision generally better than 5%. Importantly, compared to the widely used analytical practice, we can effectively save 〉60% of time （e.g., 〈24 h vs. 〉60 h）.
