We established the passive-visible spectroscopy diagnostics(P-VSD)and active-VSD(A-VSD)spectral splitting models for the HL-2A tokamak.Spectral splitting due to the influence of electromagnetic fields on the spectra i...We established the passive-visible spectroscopy diagnostics(P-VSD)and active-VSD(A-VSD)spectral splitting models for the HL-2A tokamak.Spectral splitting due to the influence of electromagnetic fields on the spectra in VSD is studied.Zeeman splitting induced by the magnetic field(B)is used to distinguish reflected light overlap in the divertor for P-VSD.Stark splitting caused by the Lorentz electric field(E_(Lorentz))from the neutral beam injection particle’s interaction with the magnetic field(V_(beam)×B)is used to measure the safety factor q profile for A-VSD.We give a comparison and error analysis by fitting the experimental spectra with the simulation results.The distinguishing of edge(scrape-off layer and divertor)hydrogen/deuterium spectral lines and the q profile derived from the spectra provides a reference for HL-2M VSD.展开更多
Simultaneous observations for the total column densities of NO2,O3 and H2O were carried on using the portable Spectrometer (438-450 nm and 400-450 nm) and the visible Spectrometer (544.4-628 nm) during premonsoon thun...Simultaneous observations for the total column densities of NO2,O3 and H2O were carried on using the portable Spectrometer (438-450 nm and 400-450 nm) and the visible Spectrometer (544.4-628 nm) during premonsoon thunderstorms and embedded hail storm activity at Pune (18°32'N & 73°51'E),India.These observations confirm the fact that there is an increase in O3 and NO2 column densities during thunderstorms.The increase in O3 was observed following onset of thunderstorm,while the increase in NO2 was observed only after the thunder flashes occur.This implies that the production mechanisms for O3 and NO2 in thunderstorm are different.The observed column density of NO,value (1 to 3×1017molecules cm-2) during thunderstorm activity is 10 to 30 times higher than the value (1×10th molecules cm-2) of a normal day total column density.The spectrometric observations and observations of thunder flashes by electric field meter showed that 6.4×1025molecules/flash of NO2 are produced.The increased to-oil column density of ozone during thunderstorm period is 1.2 times higher than normal (clear) day ozone concentration.The multiple scattering in the clouds is estimated from H2O and O2 absorption bands in the visible spectral region Considering this effect the calculated amount of ozone added in the global atmosphere due to thunderstorm activity is 0.26 to 0 52 DU,and the annual production of ozone due to thunderstorm activity is of the order of 4.02×10 molecules/year The annual NO2 production may be of the order of 2.02×1035molecules/year.展开更多
This study investigated the development of a novel approach to surface characterization of drug poly- morphism and the extension of the capabilities of this method to perform 'real time' in situ measure- ments. This...This study investigated the development of a novel approach to surface characterization of drug poly- morphism and the extension of the capabilities of this method to perform 'real time' in situ measure- ments. This was achieved using diffuse reflectance visible (DRV) spectroscopy and dye deposition, using the pH sensitive dye, thymol blue (TB). Two polymorphs, SFN-β and SFN-γ, of the drug substance sulfanilamide (SFN) were examined. The interaction of adsorbed dye with polymorphs showed different behavior, and thus reported different DRV spectra. Consideration of the acid/base properties of the morphological forms of the drug molecule provided a rationalization of the mechanism of differential coloration by indicator dyes. The kinetics of the polymorphic transformation of SFN polymorphs was monitored using treatment with TB dye and DRV spectroscopy. The thermally-induced transformation fitted a first-order solid-state kinetic model (R2=0.992), giving a rate constant of 2.43 × 10^- 2 s 1.展开更多
Using visible and near-infrared (Vis-NIR) spectroscopy combined with partial least squares (PLS) regression, the rapid reagent-free analysis model for chromium (Cr) content in tideland reclamation soil in the Pearl Ri...Using visible and near-infrared (Vis-NIR) spectroscopy combined with partial least squares (PLS) regression, the rapid reagent-free analysis model for chromium (Cr) content in tideland reclamation soil in the Pearl River Delta, China was established. Based on Savitzky-Golay (SG) smoothing and PLS regression, a multi-parameters optimization platform (SG-PLS) covering 264 modes was constructed to select the appropriately spectral preprocessing mode. The optimal SG-PLS model was determined according to the prediction effect. The selected optimal parameters <em>d, p, m</em> and LV were 2, 6, 23 and 8, respectively. Using the validation samples that were not involved in modeling, the root mean square error (SEP<sub>V</sub>), relative root mean square error (R-SEP<sub>V</sub>) and correlation coefficients (R<sub>P, V</sub>) of prediction were 11.66 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup>, 10.7% and 0.722, respectively. The results indicated that the feasibility of using Vis-NIR spectroscopy combined with SG-PLS method to analyze soil Cr content. The constructed multi-parameters optimization platform with SG-PLS is expected to be applied to a wider field of analysis. The rapid detection method has important application values to large-scale agricultural production.展开更多
The identification of soy sauce adulteration can avoid fraud, and protect the rights and interests of producers and consumers. Based on two measurement models (1 mm, 10 mm), the visible and near-infrared (Vis-NIR) spe...The identification of soy sauce adulteration can avoid fraud, and protect the rights and interests of producers and consumers. Based on two measurement models (1 mm, 10 mm), the visible and near-infrared (Vis-NIR) spectroscopy combined with standard normal variate-partial least squares-discriminant analysis (SNV-PLS-DA) was used to establish the discriminant analysis models for adulterated and brewed soy sauces. Chubang soy sauce was selected as an identification brand (negative, 70). The adulteration samples (positive, 72) were prepared by mixing Chubang soy sauce and blended soy sauce with different adulteration rates. Among them, the “blended soy sauce” sample was concocted of salt water (NaCl), monosodium glutamate (C<sub>5</sub>H<sub>10</sub>NNaO<sub>5</sub>) and caramel color (C<sub>6</sub>H<sub>8</sub>O<sub>3</sub>). The rigorous calibration-prediction-validation sample design was adopted. For the case of 1 mm, five waveband models (visible, short-NIR, long-NIR, whole NIR and whole scanning regions) were established respectively;in the case of 10 mm, three waveband models (visible, short-NIR and visible-short-NIR regions) for unsaturated absorption were also established respectively. In independent validation, the models of all wavebands in the cases of 1 mm and 10 mm have achieved good discrimination effects. For the case of 1 mm, the visible model achieved the optimal validation effect, the validation recognition-accuracy rate (RAR<sub>V</sub>) was 99.6%;while in the case of 10 mm, both the visible and visible-short-NIR models achieved the optimal validation effect (RAR<sub>V</sub> = 100%). The detection method does not require reagents and is fast and simple, which is easy to promote the application. The results can provide valuable reference for designing small dedicated spectrometers with different measurement modals and different spectral regions.展开更多
The research work was carried out for establishing a new Ultra Violet (UV)— Visible spectroscopy and Reverse phase-Ultra Fast Liquid Chromatography (RP-UFLC) method for the analysis and quantification of a biosimilar...The research work was carried out for establishing a new Ultra Violet (UV)— Visible spectroscopy and Reverse phase-Ultra Fast Liquid Chromatography (RP-UFLC) method for the analysis and quantification of a biosimilar drug, Filgrastim. Filgrastim or recombinant methionyl granulocyte colony stimulating factor (rGCSF) is a glycoprotein. It has a biological action essential for proliferation and differentiation of hematopoetic and progenitor cells. The UV and RP-UFLC work was carried on a Shimadzu UV1800 Spectrophotometer and Shimadzu Prominence LC-20AD UFLC systems, respectively. The <i>λ</i><sub>max</sub> of filgrastim was found to be 215 nm. The correlation coefficient by UV spectroscopy was found to be 0.9994 for the concentration range of 1 to 3 μg/ml in double distilled water. The Reverse phase UFLC was done by using Phenomenex C4 (25 cm × 0.46 cm internal diameter) 15 μ, 300 A° analytical column. The optimized mobile phase for binary elution was Acetonitrile and double distilled water (80:20) with a flow rate of 1 ml/min. The retention time of drug was at 3.2 min. It was observed that the response of the detector was linear in the range of 5 - 15 μg/ml with correlation coefficient value of 0.999. After developing the methods, it was assured for the intended use by validation of the analytical parameters like linearity, accuracy, precision, limit of detection, limit of quantitation, ruggedness and robustness. The results of all the parameters for both the methods were found to be within the acceptance criteria as per the International Council for Harmonisation (ICH) guidelines.展开更多
Visible spectroscopic and electrochemical methods were used to study the interactions between DNA and fuchsin basic(FB). FB has an irreversible electro-oxidation peak in 5 mmol/L Tris-HCl buffer solution at pH = 7.4...Visible spectroscopic and electrochemical methods were used to study the interactions between DNA and fuchsin basic(FB). FB has an irreversible electro-oxidation peak in 5 mmol/L Tris-HCl buffer solution at pH = 7.4 on a glassy carbon electrode(GCE). After adding certain concentration of dsDNA, the oxidation peak current of FB decreases, but the peak potential hardly changes. The visible absorption spectroscopic study shows that the binding mode of FB to dsDNA is intercalative binding and electrostatic binding when the ratio of the concentration of dsDNA to FB is smaller than 0. 2, and anew substance, which produces a new absorption peak, is obtained via a covalent binding between dsDNA and FB apart from intercalative binding and electrostatic binding when the ratio of the concentration of dsDNA to FB is larger than 0. 2. The visible absorption spectra varies no longer when the ratio of the concentration of dsDNA'to FB is larger than 1.5. A mean binding ratio of dsDNA to FB was determined to be 1.4: 1, suggesting that two complexes FB-dsDNA and FB-2dsDNA be formed. The interaction between FB and ssDNA was only electrostatic binding. The more powerful interaction of FB with dsDNA than with ssDNA may be applied for the recognition of dsDNA and ssDNA, and in DNA biosensor as hybridization indicator.展开更多
Two nondestructive methods based on visible and near-infrared(VIS-NIR)spectroscopy and X-ray image have been used for the evaluation of watermelon quality.The prediction perform-ance based on partial least squares(PLS...Two nondestructive methods based on visible and near-infrared(VIS-NIR)spectroscopy and X-ray image have been used for the evaluation of watermelon quality.The prediction perform-ance based on partial least squares(PLS)by diffuse transmittance measurement(500-1010 nm)was evaluated for_chemical quality attributes SSC(Rc=0.903;RMSEC=0.572%Brix;Rp=0.862;RMSEP=0.717%Brix;RPD=1.83),lycopene(Rc=0.845;RMSEC=0.266 mg/100 gFW;Rp=0.751;RMSEP=0.439 mg/100 gFW;RPD=1.13)and moisture(Rc=0.917;RMSEC=0.280%;Rp=0.937;RMSEP=0.276%;RPD=2.79).The X-ray calibration linearequations developed by extracting the appropriate gray threshold were sufficiently precise forvolume(R?=0.986)and weight(R?=0.993).In order to optimize prediction model of water-melon quality in growth period,multivariate multi-block technique factor analysis enabled in-tegration of these traits:chemical information is related to physical infomation.Applyingprinciple component analysis to extract common factors and varimax with Kaiser normalizationto improve explanatory,the comprehensive indicator based on variances was established satis.factorily with Rc=0.94,RMSEC=0.244,Rp=0.93,RMSEP=0.344 and RPD=2.00.Acomparison of these models indicates that the comprehensive indicator determined only by portable VIS-NIR spectrometer appears as a suitable method for appraising watermelon qualitynondestructively on the plant at diferent ripen stages.This method contributes to infer the picking date of watermelon with higher accuracy and bigger economic benefits than that byexperience.展开更多
Aim: The aim of the study is to test visible resonance Raman (VRR) spectroscopy for rapid skin cancer diagnosis,and evaluate its effectiveness as a new optical biopsy method to distinguish basal cell carcinoma (BCC) f...Aim: The aim of the study is to test visible resonance Raman (VRR) spectroscopy for rapid skin cancer diagnosis,and evaluate its effectiveness as a new optical biopsy method to distinguish basal cell carcinoma (BCC) from normal skin tissues.Methods: The VRR spectroscopic technique was undertaken using 532 nm excitation. Normal and BCC human skin tissue samples were measured in seconds. The molecular fingerprints of various native biomolecules as biomarkers were analyzed. A principal component analysis - support vector machine (PCA-SVM) statistical analysis method based on the molecular fingerprints was developed for differentiating BCC from normal skin tissues.Results: VRR provides a rapid method and enhanced Raman signals from biomolecules with resonant and nearresonant absorption bands as compared with using a near-infrared excitation light source. The VRR technique revealed chemical composition changes of native biomarkers such as tryptophan, carotenoids, lipids and proteins.The VRR spectra from BCC samples showed a strong enhancement in proteins including collagen type I combined with amide I and amino acids, and a decrease in carotenoids and lipids. The PCA-SVM statistical analysis based on the molecular fingerprints of the biomarkers yielded a 93.0% diagnostic sensitivity, 100% specificity, and 94.5%accuracy compared with histopathology reports.Conclusion: VRR can enhance molecular vibrational modes of various native biomarkers to allow for very fast display of Raman modes in seconds. It may be used as a label-free molecular pathology method for diagnosis of skin cancer and other diseases and be used for combined treatment with Mohs surgery for BCC.展开更多
Reflectance spectroscopy is rapid,inexpensive,and non-destructive and can provide important information about the mineralogy of rocks and sediments.We measured the reflectance spectroscopy of Miocene red clay deposits...Reflectance spectroscopy is rapid,inexpensive,and non-destructive and can provide important information about the mineralogy of rocks and sediments.We measured the reflectance spectroscopy of Miocene red clay deposits on the northeastern margin of the Tibetan Plateau,with the aim of developing a rapid methodology for detecting paleoclimatic changes.We obtained visible/near-infrared(VNIR)and short-wave infrared(SWIR)spectroscopy data from the red clay in the Jianzha Basin,and analyzed their relationship with independent paleoclimatic records,including mineral contents and environmental magnetic parameters.The results show that the VNIR parameters,including D500,D900,R500,and R900(where D and R represent the depth and reflectance of the absorption peaks around 500 and 900 nm,respectively)are temperature-sensitive and correlated with the magnetic susceptibility,frequency-dependent magnetic susceptibility,and the marine δ^(18)O record.The results of frequency-domain analysis of the VNIR parameters show that they reflect climate change on orbital timescales.SWIR parameters,such as AS1400,D1400/D1900 and D1900(where AS represents the asymmetry of the absorption peaks around1400 nm),are correlated with the illite and montmorillonite content,and they are sensitive to the weathering intensity.The spectral parameters of the eolian red clay in the Jianzha Basin reflect regional climatic changes caused by the uplift of the Tibetan Plateau at~8.5 Ma and global climatic cooling at~7.2 Ma,and thus they are applicable as both regional and global paleoenvironmental indicators.展开更多
In this paper a quick method was developed to determine separate furfural and HMF concentrations simultaneously in ethanol-water hydrolysate of reed based on UV spectroscopy.Acid soluble lignin and other interfering s...In this paper a quick method was developed to determine separate furfural and HMF concentrations simultaneously in ethanol-water hydrolysate of reed based on UV spectroscopy.Acid soluble lignin and other interfering substances were first removed by distillation as residue.The distillate was then used for the determination of furfural and HMF by measuring the maximum absorption wavelength and the absorbance at the wavelength.Results showed that the maximum absorption wavelength of the characteristic peak correlated well with the composition of furfural and HMF mixture in an ethanol-water solution,and the absorbance at the maximum absorption wavelength also had an excellent linear relationship with the sum concentration of furfural and HMF in the solution.The separate concentrations of furfural and HMF in a mixture solution could be determined by applying these correlations.展开更多
The occurrence of a mesoscopic scale in granular materials leads to a sharp increase in the number of interaction processes at both intra-and inter-scale levels.The mesoscopic scale is the main source of the complex m...The occurrence of a mesoscopic scale in granular materials leads to a sharp increase in the number of interaction processes at both intra-and inter-scale levels.The mesoscopic scale is the main source of the complex macroscopic properties of granular materials.The quantification of mesoscopic disordered movements is often referred to as granular temperature.In this paper,we first introduce the physical meaning of the original granular temperature of a kinetic nature,Tk,and then briefly summarize the advances made over the past few decades.Our research group has focused on Tk measurement using speckle visibility spectroscopy.The principle of this technique and the instruments developed in our research group are briefly introduced.Our work shows great promise in the measurement of kinetic granular temperature.Finally,a summary of granular temperature and some recent developments in speckle visibility spectroscopy measurements are presented.展开更多
Gafchromic external beam therapy 3(EBT3)film has widely been used in medical field applications.Principally,the EBT3 film’s color gradually changes from light green to darker color under incremental exposures by ioni...Gafchromic external beam therapy 3(EBT3)film has widely been used in medical field applications.Principally,the EBT3 film’s color gradually changes from light green to darker color under incremental exposures by ionizing or even non-ionizing ultraviolet(UV)radiation.Peak absorbance of the EBT3 film can be used to predict absorbed doses by the film.However,until today,related researches still rely on spectrometers for color analysis of EBT3 films.Hence,this paper presents a comparative analysis between results produced by the spectrometer and a much simpler light-emitting diode-photodiode based system in profiling the color changes of EBT3 films after exposure by solar UV radiation.This work has been conducted on a set of 50 EBT3 samples with incremental solar UV exposure(doses).The wavelength in the red region has the best sensitivity in profiling the color changes of EBT3 films for low solar UV exposure measurement.This study foresees the ability of blue wavelength to profile films with a large range of solar UV exposure.The LED(light emitting diode)-based optical system has produced comparable measurement accuracies to the spectrometer and thus,with a potential for replacing the need for a multipurpose spectroscopy system for simple measurement of light attenuation.展开更多
A self-organized thin film of a cyanine dye is fabricated by the spin-coating technique and is characterized by ultraviolet-visible spectroscopy, infrared (IR) spectroscopy, small-angle X-ray diffraction, eUipsomete...A self-organized thin film of a cyanine dye is fabricated by the spin-coating technique and is characterized by ultraviolet-visible spectroscopy, infrared (IR) spectroscopy, small-angle X-ray diffraction, eUipsometer, and atomic force microscopy (AFM). The nonlinear optical properties of the thin films are investigated by degenerate four wave mixing (DFWM) technique. The cyanine dye thin film sample exhibits high optical nonlinearities (χ^(3) = 2.55 × 10^-12 esu), and the mechanism is analyzed by the exciton coupling theory.展开更多
Based on the analysis technology of visible/near infrared diffuse reflectance spectroscopy a portable and nondestructive detector was designed to test comprehensive quality of red globe grape bunches in the growth per...Based on the analysis technology of visible/near infrared diffuse reflectance spectroscopy a portable and nondestructive detector was designed to test comprehensive quality of red globe grape bunches in the growth period.The detector included spectrum acquisition probe,spectrometer,lithium battery,halogen lamp light source,advanced RISC machines(ARM)board and peripheral circuit.Based on microsoft foundation classes(MFC)development tool,the real-time analysis and processing software of the detector was written by C++language.The optimal partial least squares regression(PLSR)detection model of multi-quality parameters was implanted into the hardware device.This paper selected the red globe grapes bunches in the growth period as the research samples,collected the visible/near infrared diffuse reflectance spectrum information,and then used the established PLSR model to detect the soluble solid content(SSC),total acid(TA)and pH of the samples to generate comprehensive quality parameter.So as to realize the nondestructive detecting of comprehensive quality of red globe grapes bunches in the growth period.In conclusion,the detector could realize real-time and non-destructive detecting of red globe grapes bunches in growth period aiming at the comprehensive quality.展开更多
Swarm intelligence algorithms own superior performance in solving high-dimensional and multi-objective optimization problems.The application of the swarm intelligence algorithms to visible and near-infrared(VIS-NIR)sp...Swarm intelligence algorithms own superior performance in solving high-dimensional and multi-objective optimization problems.The application of the swarm intelligence algorithms to visible and near-infrared(VIS-NIR)spectral analysis of soil moisture can contribute to the optimization of the soil moisture prediction model and the development of the real-time soil moisture sensor.In this study,a high-resolution spectrometer was used to obtain spectral data of different levels of soil moisture which were manually configured.Isolation Forest algorithm(iForest)was used to eliminate outliers from the data.Based on the root mean square error of prediction RMSEP of Back Propagation Neural Network(BPNN)model results,a series of new swarm intelligence algorithms,including Manta Ray Foraging Optimization(MRFO),Slime Mould Algorithm(SMA),etc.,were used to select the characteristic wavelengths of soil moisture.The analysis results showed that MRFO owned the best performance if only from the predictive capability perspective and SMA had a better performance when considering the proportion of the selecting wavelengths and the results of the model prediction.By comparing and analyzing the modeling results of traditional intelligence algorithms Genetic Algorithm(GA)and Particle Swarm Optimization(PSO),it was found that the new swarm intelligence had a better performance in selecting the characteristic wavelengths of soil moisture.Integrating the results of all intelligence algorithms used,soil moisture sensitive wavelengths were selected as 490 nm,513 nm,543 nm,900 nm and 926 nm,which provide the basis for the design of real-time soil moisture sensor based on VIS-NIR.展开更多
基金the National Key Research and Development Program of China(No.2019YFE03020004)National Natural Science Foundation of China(No.12175228).
文摘We established the passive-visible spectroscopy diagnostics(P-VSD)and active-VSD(A-VSD)spectral splitting models for the HL-2A tokamak.Spectral splitting due to the influence of electromagnetic fields on the spectra in VSD is studied.Zeeman splitting induced by the magnetic field(B)is used to distinguish reflected light overlap in the divertor for P-VSD.Stark splitting caused by the Lorentz electric field(E_(Lorentz))from the neutral beam injection particle’s interaction with the magnetic field(V_(beam)×B)is used to measure the safety factor q profile for A-VSD.We give a comparison and error analysis by fitting the experimental spectra with the simulation results.The distinguishing of edge(scrape-off layer and divertor)hydrogen/deuterium spectral lines and the q profile derived from the spectra provides a reference for HL-2M VSD.
文摘Simultaneous observations for the total column densities of NO2,O3 and H2O were carried on using the portable Spectrometer (438-450 nm and 400-450 nm) and the visible Spectrometer (544.4-628 nm) during premonsoon thunderstorms and embedded hail storm activity at Pune (18°32'N & 73°51'E),India.These observations confirm the fact that there is an increase in O3 and NO2 column densities during thunderstorms.The increase in O3 was observed following onset of thunderstorm,while the increase in NO2 was observed only after the thunder flashes occur.This implies that the production mechanisms for O3 and NO2 in thunderstorm are different.The observed column density of NO,value (1 to 3×1017molecules cm-2) during thunderstorm activity is 10 to 30 times higher than the value (1×10th molecules cm-2) of a normal day total column density.The spectrometric observations and observations of thunder flashes by electric field meter showed that 6.4×1025molecules/flash of NO2 are produced.The increased to-oil column density of ozone during thunderstorm period is 1.2 times higher than normal (clear) day ozone concentration.The multiple scattering in the clouds is estimated from H2O and O2 absorption bands in the visible spectral region Considering this effect the calculated amount of ozone added in the global atmosphere due to thunderstorm activity is 0.26 to 0 52 DU,and the annual production of ozone due to thunderstorm activity is of the order of 4.02×10 molecules/year The annual NO2 production may be of the order of 2.02×1035molecules/year.
文摘This study investigated the development of a novel approach to surface characterization of drug poly- morphism and the extension of the capabilities of this method to perform 'real time' in situ measure- ments. This was achieved using diffuse reflectance visible (DRV) spectroscopy and dye deposition, using the pH sensitive dye, thymol blue (TB). Two polymorphs, SFN-β and SFN-γ, of the drug substance sulfanilamide (SFN) were examined. The interaction of adsorbed dye with polymorphs showed different behavior, and thus reported different DRV spectra. Consideration of the acid/base properties of the morphological forms of the drug molecule provided a rationalization of the mechanism of differential coloration by indicator dyes. The kinetics of the polymorphic transformation of SFN polymorphs was monitored using treatment with TB dye and DRV spectroscopy. The thermally-induced transformation fitted a first-order solid-state kinetic model (R2=0.992), giving a rate constant of 2.43 × 10^- 2 s 1.
文摘Using visible and near-infrared (Vis-NIR) spectroscopy combined with partial least squares (PLS) regression, the rapid reagent-free analysis model for chromium (Cr) content in tideland reclamation soil in the Pearl River Delta, China was established. Based on Savitzky-Golay (SG) smoothing and PLS regression, a multi-parameters optimization platform (SG-PLS) covering 264 modes was constructed to select the appropriately spectral preprocessing mode. The optimal SG-PLS model was determined according to the prediction effect. The selected optimal parameters <em>d, p, m</em> and LV were 2, 6, 23 and 8, respectively. Using the validation samples that were not involved in modeling, the root mean square error (SEP<sub>V</sub>), relative root mean square error (R-SEP<sub>V</sub>) and correlation coefficients (R<sub>P, V</sub>) of prediction were 11.66 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup>, 10.7% and 0.722, respectively. The results indicated that the feasibility of using Vis-NIR spectroscopy combined with SG-PLS method to analyze soil Cr content. The constructed multi-parameters optimization platform with SG-PLS is expected to be applied to a wider field of analysis. The rapid detection method has important application values to large-scale agricultural production.
文摘The identification of soy sauce adulteration can avoid fraud, and protect the rights and interests of producers and consumers. Based on two measurement models (1 mm, 10 mm), the visible and near-infrared (Vis-NIR) spectroscopy combined with standard normal variate-partial least squares-discriminant analysis (SNV-PLS-DA) was used to establish the discriminant analysis models for adulterated and brewed soy sauces. Chubang soy sauce was selected as an identification brand (negative, 70). The adulteration samples (positive, 72) were prepared by mixing Chubang soy sauce and blended soy sauce with different adulteration rates. Among them, the “blended soy sauce” sample was concocted of salt water (NaCl), monosodium glutamate (C<sub>5</sub>H<sub>10</sub>NNaO<sub>5</sub>) and caramel color (C<sub>6</sub>H<sub>8</sub>O<sub>3</sub>). The rigorous calibration-prediction-validation sample design was adopted. For the case of 1 mm, five waveband models (visible, short-NIR, long-NIR, whole NIR and whole scanning regions) were established respectively;in the case of 10 mm, three waveband models (visible, short-NIR and visible-short-NIR regions) for unsaturated absorption were also established respectively. In independent validation, the models of all wavebands in the cases of 1 mm and 10 mm have achieved good discrimination effects. For the case of 1 mm, the visible model achieved the optimal validation effect, the validation recognition-accuracy rate (RAR<sub>V</sub>) was 99.6%;while in the case of 10 mm, both the visible and visible-short-NIR models achieved the optimal validation effect (RAR<sub>V</sub> = 100%). The detection method does not require reagents and is fast and simple, which is easy to promote the application. The results can provide valuable reference for designing small dedicated spectrometers with different measurement modals and different spectral regions.
文摘The research work was carried out for establishing a new Ultra Violet (UV)— Visible spectroscopy and Reverse phase-Ultra Fast Liquid Chromatography (RP-UFLC) method for the analysis and quantification of a biosimilar drug, Filgrastim. Filgrastim or recombinant methionyl granulocyte colony stimulating factor (rGCSF) is a glycoprotein. It has a biological action essential for proliferation and differentiation of hematopoetic and progenitor cells. The UV and RP-UFLC work was carried on a Shimadzu UV1800 Spectrophotometer and Shimadzu Prominence LC-20AD UFLC systems, respectively. The <i>λ</i><sub>max</sub> of filgrastim was found to be 215 nm. The correlation coefficient by UV spectroscopy was found to be 0.9994 for the concentration range of 1 to 3 μg/ml in double distilled water. The Reverse phase UFLC was done by using Phenomenex C4 (25 cm × 0.46 cm internal diameter) 15 μ, 300 A° analytical column. The optimized mobile phase for binary elution was Acetonitrile and double distilled water (80:20) with a flow rate of 1 ml/min. The retention time of drug was at 3.2 min. It was observed that the response of the detector was linear in the range of 5 - 15 μg/ml with correlation coefficient value of 0.999. After developing the methods, it was assured for the intended use by validation of the analytical parameters like linearity, accuracy, precision, limit of detection, limit of quantitation, ruggedness and robustness. The results of all the parameters for both the methods were found to be within the acceptance criteria as per the International Council for Harmonisation (ICH) guidelines.
文摘Visible spectroscopic and electrochemical methods were used to study the interactions between DNA and fuchsin basic(FB). FB has an irreversible electro-oxidation peak in 5 mmol/L Tris-HCl buffer solution at pH = 7.4 on a glassy carbon electrode(GCE). After adding certain concentration of dsDNA, the oxidation peak current of FB decreases, but the peak potential hardly changes. The visible absorption spectroscopic study shows that the binding mode of FB to dsDNA is intercalative binding and electrostatic binding when the ratio of the concentration of dsDNA to FB is smaller than 0. 2, and anew substance, which produces a new absorption peak, is obtained via a covalent binding between dsDNA and FB apart from intercalative binding and electrostatic binding when the ratio of the concentration of dsDNA to FB is larger than 0. 2. The visible absorption spectra varies no longer when the ratio of the concentration of dsDNA'to FB is larger than 1.5. A mean binding ratio of dsDNA to FB was determined to be 1.4: 1, suggesting that two complexes FB-dsDNA and FB-2dsDNA be formed. The interaction between FB and ssDNA was only electrostatic binding. The more powerful interaction of FB with dsDNA than with ssDNA may be applied for the recognition of dsDNA and ssDNA, and in DNA biosensor as hybridization indicator.
基金supported by the national nat uralscience foundation(NSFC)(NO.31071555)to provide financial support and the earmarked fund for Modern Agro-industry Technology Research System(NO.CARS-26-22)to measure referencevalues using traditional methods.
文摘Two nondestructive methods based on visible and near-infrared(VIS-NIR)spectroscopy and X-ray image have been used for the evaluation of watermelon quality.The prediction perform-ance based on partial least squares(PLS)by diffuse transmittance measurement(500-1010 nm)was evaluated for_chemical quality attributes SSC(Rc=0.903;RMSEC=0.572%Brix;Rp=0.862;RMSEP=0.717%Brix;RPD=1.83),lycopene(Rc=0.845;RMSEC=0.266 mg/100 gFW;Rp=0.751;RMSEP=0.439 mg/100 gFW;RPD=1.13)and moisture(Rc=0.917;RMSEC=0.280%;Rp=0.937;RMSEP=0.276%;RPD=2.79).The X-ray calibration linearequations developed by extracting the appropriate gray threshold were sufficiently precise forvolume(R?=0.986)and weight(R?=0.993).In order to optimize prediction model of water-melon quality in growth period,multivariate multi-block technique factor analysis enabled in-tegration of these traits:chemical information is related to physical infomation.Applyingprinciple component analysis to extract common factors and varimax with Kaiser normalizationto improve explanatory,the comprehensive indicator based on variances was established satis.factorily with Rc=0.94,RMSEC=0.244,Rp=0.93,RMSEP=0.344 and RPD=2.00.Acomparison of these models indicates that the comprehensive indicator determined only by portable VIS-NIR spectrometer appears as a suitable method for appraising watermelon qualitynondestructively on the plant at diferent ripen stages.This method contributes to infer the picking date of watermelon with higher accuracy and bigger economic benefits than that byexperience.
基金This preliminary work was supported in part by a seed grant from Sinai hospital of Detroit medical staff foundation
文摘Aim: The aim of the study is to test visible resonance Raman (VRR) spectroscopy for rapid skin cancer diagnosis,and evaluate its effectiveness as a new optical biopsy method to distinguish basal cell carcinoma (BCC) from normal skin tissues.Methods: The VRR spectroscopic technique was undertaken using 532 nm excitation. Normal and BCC human skin tissue samples were measured in seconds. The molecular fingerprints of various native biomolecules as biomarkers were analyzed. A principal component analysis - support vector machine (PCA-SVM) statistical analysis method based on the molecular fingerprints was developed for differentiating BCC from normal skin tissues.Results: VRR provides a rapid method and enhanced Raman signals from biomolecules with resonant and nearresonant absorption bands as compared with using a near-infrared excitation light source. The VRR technique revealed chemical composition changes of native biomarkers such as tryptophan, carotenoids, lipids and proteins.The VRR spectra from BCC samples showed a strong enhancement in proteins including collagen type I combined with amide I and amino acids, and a decrease in carotenoids and lipids. The PCA-SVM statistical analysis based on the molecular fingerprints of the biomarkers yielded a 93.0% diagnostic sensitivity, 100% specificity, and 94.5%accuracy compared with histopathology reports.Conclusion: VRR can enhance molecular vibrational modes of various native biomarkers to allow for very fast display of Raman modes in seconds. It may be used as a label-free molecular pathology method for diagnosis of skin cancer and other diseases and be used for combined treatment with Mohs surgery for BCC.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research(STEP)Program(Grant Nos.2019QZKK0704&2019QZKK0101)the National Natural Science Foundation of China(Grant Nos.42272221&41772167)+1 种基金the State Key Laboratory of Loess and Quaternary Geology(Grant No.SKLLQG1905)the Central University Research Foundation,Chang’an University(Grant Nos.300102272901)。
文摘Reflectance spectroscopy is rapid,inexpensive,and non-destructive and can provide important information about the mineralogy of rocks and sediments.We measured the reflectance spectroscopy of Miocene red clay deposits on the northeastern margin of the Tibetan Plateau,with the aim of developing a rapid methodology for detecting paleoclimatic changes.We obtained visible/near-infrared(VNIR)and short-wave infrared(SWIR)spectroscopy data from the red clay in the Jianzha Basin,and analyzed their relationship with independent paleoclimatic records,including mineral contents and environmental magnetic parameters.The results show that the VNIR parameters,including D500,D900,R500,and R900(where D and R represent the depth and reflectance of the absorption peaks around 500 and 900 nm,respectively)are temperature-sensitive and correlated with the magnetic susceptibility,frequency-dependent magnetic susceptibility,and the marine δ^(18)O record.The results of frequency-domain analysis of the VNIR parameters show that they reflect climate change on orbital timescales.SWIR parameters,such as AS1400,D1400/D1900 and D1900(where AS represents the asymmetry of the absorption peaks around1400 nm),are correlated with the illite and montmorillonite content,and they are sensitive to the weathering intensity.The spectral parameters of the eolian red clay in the Jianzha Basin reflect regional climatic changes caused by the uplift of the Tibetan Plateau at~8.5 Ma and global climatic cooling at~7.2 Ma,and thus they are applicable as both regional and global paleoenvironmental indicators.
基金National Natural Science Foundation of China for financial support for this research (Grant#:31270634).
文摘In this paper a quick method was developed to determine separate furfural and HMF concentrations simultaneously in ethanol-water hydrolysate of reed based on UV spectroscopy.Acid soluble lignin and other interfering substances were first removed by distillation as residue.The distillate was then used for the determination of furfural and HMF by measuring the maximum absorption wavelength and the absorbance at the wavelength.Results showed that the maximum absorption wavelength of the characteristic peak correlated well with the composition of furfural and HMF mixture in an ethanol-water solution,and the absorbance at the maximum absorption wavelength also had an excellent linear relationship with the sum concentration of furfural and HMF in the solution.The separate concentrations of furfural and HMF in a mixture solution could be determined by applying these correlations.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.11572201,11572178,and 91634202)the Innovation Program of Shanghai Municipal Education Commission(Grant No.15ZZ072).
文摘The occurrence of a mesoscopic scale in granular materials leads to a sharp increase in the number of interaction processes at both intra-and inter-scale levels.The mesoscopic scale is the main source of the complex macroscopic properties of granular materials.The quantification of mesoscopic disordered movements is often referred to as granular temperature.In this paper,we first introduce the physical meaning of the original granular temperature of a kinetic nature,Tk,and then briefly summarize the advances made over the past few decades.Our research group has focused on Tk measurement using speckle visibility spectroscopy.The principle of this technique and the instruments developed in our research group are briefly introduced.Our work shows great promise in the measurement of kinetic granular temperature.Finally,a summary of granular temperature and some recent developments in speckle visibility spectroscopy measurements are presented.
基金This work was financially supported by the Ministry of Higher Education Malaysia-Fundamental Research Grant Scheme(Grant No.203/PFIZIK/6711491).
文摘Gafchromic external beam therapy 3(EBT3)film has widely been used in medical field applications.Principally,the EBT3 film’s color gradually changes from light green to darker color under incremental exposures by ionizing or even non-ionizing ultraviolet(UV)radiation.Peak absorbance of the EBT3 film can be used to predict absorbed doses by the film.However,until today,related researches still rely on spectrometers for color analysis of EBT3 films.Hence,this paper presents a comparative analysis between results produced by the spectrometer and a much simpler light-emitting diode-photodiode based system in profiling the color changes of EBT3 films after exposure by solar UV radiation.This work has been conducted on a set of 50 EBT3 samples with incremental solar UV exposure(doses).The wavelength in the red region has the best sensitivity in profiling the color changes of EBT3 films for low solar UV exposure measurement.This study foresees the ability of blue wavelength to profile films with a large range of solar UV exposure.The LED(light emitting diode)-based optical system has produced comparable measurement accuracies to the spectrometer and thus,with a potential for replacing the need for a multipurpose spectroscopy system for simple measurement of light attenuation.
基金This work was supported by the National Natural Science Foundation of China(No.10574046)the National Key Project for Basic Research of China(No.2006CB806006 and 2006CB921105)+4 种基金the Program for Changjiang Scholars and Innovative Research Team in University(PCSIRT)the Program for New Century Excellent Talents in University(NCET-04-0420)the Doctoral Program of High Education(No.20050269011)the Phosphor Program sponsored by Shanghai Science Technology Committee(No. 06QH14003)the Twilight Project sponsored by Shanghai Education Committee(No.03SG23).
文摘A self-organized thin film of a cyanine dye is fabricated by the spin-coating technique and is characterized by ultraviolet-visible spectroscopy, infrared (IR) spectroscopy, small-angle X-ray diffraction, eUipsometer, and atomic force microscopy (AFM). The nonlinear optical properties of the thin films are investigated by degenerate four wave mixing (DFWM) technique. The cyanine dye thin film sample exhibits high optical nonlinearities (χ^(3) = 2.55 × 10^-12 esu), and the mechanism is analyzed by the exciton coupling theory.
基金This study was funded by National Natural Science Foundation of China(32072302)Hubei Provincial(China)Natural Science Foundation(2012FKB02910)Hubei Research and Development Program(2011BHB016)。
文摘Based on the analysis technology of visible/near infrared diffuse reflectance spectroscopy a portable and nondestructive detector was designed to test comprehensive quality of red globe grape bunches in the growth period.The detector included spectrum acquisition probe,spectrometer,lithium battery,halogen lamp light source,advanced RISC machines(ARM)board and peripheral circuit.Based on microsoft foundation classes(MFC)development tool,the real-time analysis and processing software of the detector was written by C++language.The optimal partial least squares regression(PLSR)detection model of multi-quality parameters was implanted into the hardware device.This paper selected the red globe grapes bunches in the growth period as the research samples,collected the visible/near infrared diffuse reflectance spectrum information,and then used the established PLSR model to detect the soluble solid content(SSC),total acid(TA)and pH of the samples to generate comprehensive quality parameter.So as to realize the nondestructive detecting of comprehensive quality of red globe grapes bunches in the growth period.In conclusion,the detector could realize real-time and non-destructive detecting of red globe grapes bunches in growth period aiming at the comprehensive quality.
基金supported by the National Natural Science Foundation of China(NSFC,22002123 and U1862111)Sichuan Science and Technology Program(2020YFH0118,2021JDGD0029 and 2021YFH0055)+6 种基金the Open Fund of State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation(PLN201802)the Independent Research Fund Denmark-Nature Sciences(DFF-FNU,DFF-7014-00302)the Independent Research Fund Denmark-Sapere Aude starting grant(7026-00037A)the Research Fund for International Young Scientists from NSFC(21950410515)Swedish Research Council VR Starting Grant(2017-05337)the financial support from China Scholarship Council(201806320345,201908440313,201706170017,and 201806460021)Support from Swedish Energy Agency。
基金supported by the National Natural Science Foundation of China(Grant No.32071915)China Agriculture Research System of MOF and MARA-Food Legumes(CARS-08).
文摘Swarm intelligence algorithms own superior performance in solving high-dimensional and multi-objective optimization problems.The application of the swarm intelligence algorithms to visible and near-infrared(VIS-NIR)spectral analysis of soil moisture can contribute to the optimization of the soil moisture prediction model and the development of the real-time soil moisture sensor.In this study,a high-resolution spectrometer was used to obtain spectral data of different levels of soil moisture which were manually configured.Isolation Forest algorithm(iForest)was used to eliminate outliers from the data.Based on the root mean square error of prediction RMSEP of Back Propagation Neural Network(BPNN)model results,a series of new swarm intelligence algorithms,including Manta Ray Foraging Optimization(MRFO),Slime Mould Algorithm(SMA),etc.,were used to select the characteristic wavelengths of soil moisture.The analysis results showed that MRFO owned the best performance if only from the predictive capability perspective and SMA had a better performance when considering the proportion of the selecting wavelengths and the results of the model prediction.By comparing and analyzing the modeling results of traditional intelligence algorithms Genetic Algorithm(GA)and Particle Swarm Optimization(PSO),it was found that the new swarm intelligence had a better performance in selecting the characteristic wavelengths of soil moisture.Integrating the results of all intelligence algorithms used,soil moisture sensitive wavelengths were selected as 490 nm,513 nm,543 nm,900 nm and 926 nm,which provide the basis for the design of real-time soil moisture sensor based on VIS-NIR.