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Fourier transform infrared spectroscopy analysis of the active components in serum of rats treated with Zuogui Pill 被引量:1
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作者 Yingli Wang Kaixia Xu +1 位作者 Yani Li Qianjin Feng 《Journal of Traditional Chinese Medical Sciences》 2015年第4期264-269,共6页
Objective:To investigate the active components Zuogui Pill,a typical recipe for nourishing kidney essence in the traditional Chinese medicine.Methods:Adult male Sprague Dawley rats were treated with the traditional Ch... Objective:To investigate the active components Zuogui Pill,a typical recipe for nourishing kidney essence in the traditional Chinese medicine.Methods:Adult male Sprague Dawley rats were treated with the traditional Chinese herbal medicine Zuogui Pill and the active components found in the serum of the animals were analyzed by Fourier transform infrared(FTIR)spectroscopy.FTIR spectra of serum samples of treated and untreated rats were analyzed and the A2960/A2931 and A1540/A1080 ratios were calculated.Results:A2960/A2931 ratios of the serum samples collected following the administration of Zuogui Pill were significantly higher than those of the normal serum samples.FTIR data were then fitted using a Gaussian equation for wave numbers in the range of 1140e1000 cm1.ARNA/ADNA ratios in the serum of rats treated with Zuogui Pill were higher than those found in normal rat serum.Conclusion:FTIR spectroscopy could be used as an analytical tool to detect the activecomponents in serum of animals treated with Zuogui Pill. 展开更多
关键词 Zuogui Pill fourier transform infrared spectroscopy SERUM FITTING
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Identification of Plant-Pathogenic Fungi Using Fourier Transform Infrared Spectroscopy Combined with Chemometric Analyses
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作者 CHAI A-li WANG Yi-kai +3 位作者 ZHU Fa-di SHI Yan-xia XIE Xue-wen LI Bao-ju 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2016年第11期3764-3771,共8页
Identification of plant-pathogenic fungi is time-consuming due to cultivation and microscopic examination and can be influenced by the interpretation of the micro-morphological characters observed.The present investig... Identification of plant-pathogenic fungi is time-consuming due to cultivation and microscopic examination and can be influenced by the interpretation of the micro-morphological characters observed.The present investigation aimed to create a simple but sophisticated method for the identification of plant-pathogenic fungi by Fourier transform infrared(FTIR)spectroscopy.In this study,FTIR-attenuated total reflectance(ATR)spectroscopy was used in combination with chemometric analysis for identification of important pathogenic fungi of horticultural plants.Mixtures of mycelia and spores from 27fungal strains belonging to nine different families were collected from liquid PD or solid PDA media cultures and subjected to FTIR-ATR spectroscopy measurements.The FTIR-ATR spectra ranging from 4 000to 400cm-1 were obtained.To classify the FTIRATR spectra,cluster analysis was compared with canonical vitiate analysis(CVA)in the spectral regions of3 050~2 800and 1 800~900cm-1.Results showed that the identification accuracies achieved 97.53%and99.18%for the cluster analysis and CVA analysis,respectively,demonstrating the high potential of this technique for fungal strain identification. 展开更多
关键词 fourier transform infrared spectroscopy(FTIR) Plant-pathogenic fungi IDENTIFICATION Cluster analysis Canonical vitiate analysis
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GP Algorithm-Based Fourier Transform Infrared Spectrum Trend Term Removal Model
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作者 Bo Yan Shuaihui Li Hao Chen 《Journal of Beijing Institute of Technology》 EI CAS 2023年第1期41-51,共11页
Trend term removal is a key step in Fourier transform infrared spectroscopy(FTIR)data pre-processing.The most commonly used least squares(LS)method,although satisfying the real-time requirement,has many problems such ... Trend term removal is a key step in Fourier transform infrared spectroscopy(FTIR)data pre-processing.The most commonly used least squares(LS)method,although satisfying the real-time requirement,has many problems such as highly correlated initial values of the expression parameters,the need to pre-estimate the trend term shape,and poor fitting accuracy at low signal-to-noise ratios.In order to achieve real-time and robust trend term removal,a new trend term removal method using genetic programming(GP)in symbolic regression is constructed in this paper,and the FTIR simulation interference results and experimental measurement data for common volatile organic compounds(VOCs)gases are analyzed.The results show that the genetic programming algorithm can both reduce the initial value requirement and greatly improve the trend term accuracy by 20%-30% in three evaluation indicators,which is suitable for gas FTIR detection in complex scenarios. 展开更多
关键词 fourier transform infrared spectroscopy(FTIR) genetic programming(GP) trend term removal
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Quantification of TOC and TN in reservoir sediments using Fourier transform infrared spectroscopy 被引量:1
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作者 Lin Mei Yihong Yue +2 位作者 Yong Qin Xueping Chen Fushun Wang 《Soil Ecology Letters》 CAS 2022年第4期399-408,共10页
This study aims to quantitatively assess the total organic carbon(TOC)and total nitrogen(TN)content of reservoir sediments in southwest China using Fourier transform infrared spectroscopy(FTIRS).FTIRS measurements wer... This study aims to quantitatively assess the total organic carbon(TOC)and total nitrogen(TN)content of reservoir sediments in southwest China using Fourier transform infrared spectroscopy(FTIRS).FTIRS measurements were performed on 187 sediment samples from four reservoirs to develop calibration models that relate FTIR spectral information with conventional property concentrations using partial least squares regression(PLSR).Robust calibration models were established for TOC and TN content.The external validation of these models yielded a significant correlation between FTIR-inferred and conventionally measured concentrations of R^(2)=0.88 for TOC,R^(2)=0.90 for TN.This method can be performed with a small sample size and is non-destructive throughout the simple measurement process.The TOC and TN content in the sediment can be determined with high effectiveness without being overly expensive,making it an advantageous method when measuring a large number of samples. 展开更多
关键词 fourier transform infrared spectroscopy CHEMOMETRICS Total organic carbon Total nitrogen Reservoir sediment
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Infrared Spectroscopy-Based Chemometric Analysis for Lard Differentiation in Meat Samples
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作者 Muhammad Aadil Siddiqui M.H.Md Khir +3 位作者 Zaka Ullah Muath Al Hasan Abdul Saboor Saeed Ahmed Magsi 《Computers, Materials & Continua》 SCIE EI 2023年第5期2859-2871,共13页
One of the most pressing concerns for the consumer market is the detection of adulteration in meat products due to their preciousness.The rapid and accurate identification mechanism for lard adulteration in meat produ... One of the most pressing concerns for the consumer market is the detection of adulteration in meat products due to their preciousness.The rapid and accurate identification mechanism for lard adulteration in meat products is highly necessary,for developing a mechanism trusted by consumers and that can be used to make a definitive diagnosis.Fourier Transform Infrared Spectroscopy(FTIR)is used in this work to identify lard adulteration in cow,lamb,and chicken samples.A simplified extraction method was implied to obtain the lipids from pure and adulterated meat.Adulterated samples were obtained by mixing lard with chicken,lamb,and beef with different concentrations(10%–50%v/v).Principal component analysis(PCA)and partial least square(PLS)were used to develop a calibration model at 800–3500 cm^(−1).Three-dimension PCA was successfully used by dividing the spectrum in three regions to classify lard meat adulteration in chicken,lamb,and beef samples.The corresponding FTIR peaks for the lard have been observed at 1159.6,1743.4,2853.1,and 2922.5 cm−1,which differentiate chicken,lamb,and beef samples.The wavenumbers offer the highest determination coefficient R2 value of 0.846 and lowest root mean square error of calibration(RMSEC)and root mean square error prediction(RMSEP)with an accuracy of 84.6%.Even the tiniest fat adulteration up to 10%can be reliably discovered using this methodology. 展开更多
关键词 fourier transform infrared spectroscopy LARD HALAL PCA PLS RMSEC RMSEP
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Fourier transform infrared spectral features of plant biomass components during cotton organ development and their biological implications
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作者 HE Zhongqi LIU Yongliang +2 位作者 KIM Hee Jin TEWOLDE Haile ZHANG Hailin 《Journal of Cotton Research》 2022年第2期130-142,共13页
Background:The majority of attenuated total reflection Fourier transform infrared(ATR FT-IR)investigations of cotton are focused on the fiber tissue for biological mechanisms and understanding of fiber development and... Background:The majority of attenuated total reflection Fourier transform infrared(ATR FT-IR)investigations of cotton are focused on the fiber tissue for biological mechanisms and understanding of fiber development and maturity,but rarely on other cotton biomass comp on ents.This work examined in detail the ATR FT-IR spectral features of various cott on tissues/organs at reproductive and maturation stages,an a lyzed and discussed their biological implications.Results:The ATR FT-IR spectra of these tissues/organs were an a lyzed and compared with the focus on the lower wavenumber fingerprinting range.Six outstanding FT-IR bands at 1730,1620,1525,1235,1050 and 895 cm^(-1) represented the major C=O stretching,protein Amide I,Amide II,the O-H/N-H deformation,the total C-O-C stretching and the β-glycosidic linkage in celluloses,respectively,and impacted differently between these organs with the two growth stages.Furthermore,the band intensity at 1620,1525,1235,and 1050 cm^(-1) were exclusively and significantly correlated to the levels of protein(Amide I bond),protein(Amide II bond),cellulose,and hemicellulose,respectively,whereas the band at 1730 cm^(-1) was negatively correlated with ash content.Conclusions:The resulting observations indicated the capability of ATR FT-IR spectroscopy for monitoring changes,transportation,and accumulation of the major chemical components in these tissues over the cotton growth period.In other words,this spectral technology could be an effective tool for physiological,biochemical,and morphological research related to cotton biology and development. 展开更多
关键词 COTTON fourier transform infrared spectroscopy FIBER CELLULOSE PROTEIN Plant tissue
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Determination of creatinine level in patient blood samples by Fourier NIR spectroscopy and multivariate analysis in comparison with biochemical assay
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作者 Zvi Hai Barnea(Burbea) David Abookasis 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2019年第6期46-55,共10页
In this paper,in vivo spectra from 23 patients'blood samples with various Creatinine(Cr)concentration levels ranging from 0.96 to 12.5 mg/dL were measured using Fourier transform near-infrared spectrometer(FT-NIRS... In this paper,in vivo spectra from 23 patients'blood samples with various Creatinine(Cr)concentration levels ranging from 0.96 to 12.5 mg/dL were measured using Fourier transform near-infrared spectrometer(FT-NIRS)and spectrum quantitative analysis method.Since Cr undergoes passive filtration,it serves as a key biomarker of kidneys function via the estimation of glomerular filtration rate.Thus,increased blood Cr concentration reflects impaired renal func-tion.After spectra pre processing and outlier exclusion,a spectral model was developed based on partial least squares regression(PLSR)method,wherein Cr concentrations correlated with filtered NIR spectra across several peaks,where Cr is know n to absorb NIR light.Several statistical metrics were applied to estimate the model efficiency during data analysis.Comparison of spectra-derived concentrations to reference Cr measurements by the current gold-standard Jaffe's method held in hospital lab revealed a Cr prediction accuracy of 1.64 mg/dL with good corre-lation of R=0.9.Bland-Altman plots were used to compare between our calculations and ref-erence lab values and reveal minimal bias between the two.The finding presented the potential of FT-NIRS coupled with PLSR technique for Cr determination. 展开更多
关键词 CREATININE fourier transform near infrared spectroscopy blood samples chemo metrics statistical analysis
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Thermal,infrared spectroscopy and molecular modeling characterization of bone:An insight in the apatite-collagen type I interaction
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作者 Alejandro Heredia Maria Colin-Garcia +5 位作者 Miguel A.Pena-Rico Jose Grácio Flavio F.Contreras-Torres Andrés Rodríguez-Galván Lauro Bucio Vladimir A.Basiuk 《Advances in Biological Chemistry》 2013年第2期215-223,共9页
An insight into the interaction of collagen type I with apatite in bone tissue was performed by using differential scanning calorimetry, Fourier transform infrared spectroscopy, and molecular modeling. Scanning electr... An insight into the interaction of collagen type I with apatite in bone tissue was performed by using differential scanning calorimetry, Fourier transform infrared spectroscopy, and molecular modeling. Scanning electron microscopy shows that bone organic content incinerate gradually through the different temperatures studied. We suggest that the amide regions of the type I collagen molecule (mainly C=O groups of the peptide bonds) will be important in the control of the interactions with the apatite from bone. The amide I infrared bands of the collagen type I change when interacting to apatite, what might confirm our assumption. Bone tissue results in a loss of thermal stability compared to the collagen studied apart, as a consequence of the degradation and further combustion of the collagen in contact with the apatite microcrystals in bone. The thermal behavior of bone is very distinctive. Its main typical combustion temperature is at 360°C with a shoulder at 550°C compared to the thermal behavior of collagen, with the mean combustion peak at ca. 500°C. Our studies with molecular mechanics (MM+ force field) showed different interaction energies of the collagen-like molecule and different models of the apatite crystal planes. We used models of the apatite (100) and (001) planes;additional two planes (001) were explored with phosphate-rich and calcium-rich faces;an energetic preference was found in the latter case. We preliminary conclude that the peptide bond of collagen type I is modified when the molecule interacts with the apatite, producing a decrease in the main peak from ca. 500°C in collagen, up to 350°C in bone. The combustion might be related to collagen type I, as the ΔH energies present only small variations between mineralized and non-mineralized samples. The data obtained here give a molecular perspective into the structural properties of bone and the change in collagen properties caused by the interaction with the apatite. Our study can be useful to understand the biological synthesis of minerals as well as the organic-inorganic interaction and the synthesis of apatite implant materials. 展开更多
关键词 Bone Collagen Type I APATITE Differential Scanning Calorimetry(DSC) Molecular Modeling fourier transform infrared(FTIR)spectroscopy
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Cluster Analysis for IR and NIR Spectroscopy: Current Practices to Future Perspectives
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作者 Simon Crase Benjamin Hall Suresh N.Thennadil 《Computers, Materials & Continua》 SCIE EI 2021年第11期1945-1965,共21页
Supervised machine learning techniques have become well established in the study of spectroscopy data.However,the unsupervised learning technique of cluster analysis hasn’t reached the same level maturity in chemomet... Supervised machine learning techniques have become well established in the study of spectroscopy data.However,the unsupervised learning technique of cluster analysis hasn’t reached the same level maturity in chemometric analysis.This paper surveys recent studies which apply cluster analysis to NIR and IR spectroscopy data.In addition,we summarize the current practices in cluster analysis of spectroscopy and contrast these with cluster analysis literature from the machine learning and pattern recognition domain.This includes practices in data pre-processing,feature extraction,clustering distance metrics,clustering algorithms and validation techniques.Special consideration is given to the specific characteristics of IR and NIR spectroscopy data which typically includes high dimensionality and relatively low sample size.The findings highlighted a lack of quantitative analysis and evaluation in current practices for cluster analysis of IR and NIR spectroscopy data.With this in mind,we propose an analysis model or workflow with techniques specifically suited for cluster analysis of IR and NIR spectroscopy data along with a pragmatic application strategy. 展开更多
关键词 CHEMOMETRICS cluster analysis fourier transform infrared spectroscopy machine learning near infrared spectroscopy unsupervised learning
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Development of Active Films with Collagen Fiber and Polyvinyl Alcohol Mixture and Incorporation of Oregano and Rosemary Essential Oils in Their Matrix
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作者 Suslin Raatz Thiel Mari Silvia Rodrigues De Oliveira +5 位作者 Vinícius Badia Stephanie Reis Ribeiro Roger Wagner Tatiana Emanuelli Rosa Cristina Prestes Renius Mello 《Food and Nutrition Sciences》 2023年第7期601-625,共25页
The aim was to develop films with a new mixture of collagen fiber plus polyvinyl alcohol added of oregano or rosemary essential oils at different levels (0%, 2%, 4% and 6%), as well as to assess the antimicrobial acti... The aim was to develop films with a new mixture of collagen fiber plus polyvinyl alcohol added of oregano or rosemary essential oils at different levels (0%, 2%, 4% and 6%), as well as to assess the antimicrobial activity, physical, optical, microstructure and molecular properties in the films. An interaction between the ingredients was observed at the molecular level by FTIR. The amide II and amide III bands, which are important to verify collagen conformation, showed intense peaks in the films. The formation of a network through collagen fibers was produced, acting as a reinforcement in matrix. The films with essential oil had an expressive antimicrobial activity by the steam contact method (micro-atmosphere), mainly for Escherichia coli and Staphylococcus aureus. The mixture of collagen fiber plus polyvinyl alcohol added of essential oils is a promising matrix for application in food as active packaging. 展开更多
关键词 Antimicrobial Activity Biodegradable Packaging Bioactive Volatile Compounds fourier transformed infrared spectroscopy Scanning Electron Microscopy Sustainable Packaging
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Percutaneous penetration enhancement effect of essential oil of mint (Mentha haplocalyx Briq.) on Chinese herbal components with different lipophilicity 被引量:4
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作者 Jingyan Wang Yi Lan +4 位作者 Hui Li Yewen Zhang Qing Zhang Yanfeng Cao Qing Wu 《Journal of Traditional Chinese Medical Sciences》 2014年第2期109-119,共11页
Objective:To investigate the percutaneous penetration effect of essential oil of mint from Mentha haplocalyx Briq.on the complex active components in Chinese herbal external preparations,and assess its toxicity on the... Objective:To investigate the percutaneous penetration effect of essential oil of mint from Mentha haplocalyx Briq.on the complex active components in Chinese herbal external preparations,and assess its toxicity on the skin cells.Methods:The cytotoxicity of mint oil on HaCaT keratinocytes and CCC-ESF-1 fibroblasts was measured using an MTT assay.Five model drugs with a wide range of lipophilicity,namely osthole,tetramethylpyrazine,ferulic acid,puerarin,and geniposide,were tested using in vitro permeation studies to investigate the percutaneous penetration enhancement effect of mint oil.Secondary structure alterations of skin stratum corneum(SC)were measured using Fourier transform infrared spectroscopy(FTIR).Saturation solubilities and SC/vehicle partition coefficients of the five model drugs with and without mint oil were also determined to understand the potential mechanisms of the essential oil.Results:Half maximal inhibitory concentration(IC50)values of mint oil were significantly higher in HaCaT and CCC-ESF-1 cell lines than values in the well-established and standard penetration enhancer Azone.Conclusions:Mint oil at proper concentration could effectively facilitate percutaneous penetration of both lipophilic and hydrophilic drugs,and exhibit higher efficiency for moderate hydrophilic drugs.Mechanisms of penetration enhancement by mint oil could be explained with saturation solubility,SC/vehicle partition coefficient and the secondary structure change of SC. 展开更多
关键词 MINT Essential oil Penetration enhancer Transdermal delivery fourier transform infrared spectroscopy
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Terahertz Generation Using Implanted InGaAs Photomixers and Multi-wavelength Quantum Dot Lasers 被引量:1
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作者 Y.Hou J.R.Liu +6 位作者 M.Buchanan A.J.Spring Thorpe P.J.Poole H.C.Liu Ke Wu Sjoerd Roorda X.P.Zhang 《Nano-Micro Letters》 SCIE EI CAS 2012年第1期10-13,共4页
We report on a study of terahertz(THz) generation using implanted In Ga As photomixers and multi-wavelength quantum dot lasers. We carry out In Ga As materials growth, optical characterization, device design and fabri... We report on a study of terahertz(THz) generation using implanted In Ga As photomixers and multi-wavelength quantum dot lasers. We carry out In Ga As materials growth, optical characterization, device design and fabrication, and photomixing experiments. This approach is capable of generating a comb of electromagnetic radiation from microwave to terahertz. For shortening photomixer carrier lifetime, we employ proton implantation into an epitaxial layer of lattice matched In Ga As grown on InP. Under a 1.55 μm multimode In GaAs/In GaAsP quantum dot laser excitation, a frequency comb with a constant frequency spacing of 50 GHz generated on the photomixer is measured, which corresponds to the beats of the laser longitudinal modes. The measurement is performed with a Fourier transform infrared spectrometer. This approach affords a convenient method to achieve a broadband multi-peak coherent THz source. 展开更多
关键词 Proton implanted In Ga As Trahertz Photomixer Multi-wavelength quantum dot laser fourier transform infrared spectroscopy
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Immunomodulating Activities of Polysaccharides from ZhuQin Formula and Atractylodes in Hypoimmune Mice 被引量:1
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作者 Min PANG Yichen LUO +3 位作者 Yongfeng HAO Xin YUE Zhaorong ZHU Juan LIU 《Medicinal Plant》 CAS 2018年第1期67-71,共5页
[Objectives] To investigate the infrared identification of ZhuQin Formula and Atractylodes polysaccharides and its effect on immune function in immunocompromised mice. [Methods] In this experiment,the structure of pol... [Objectives] To investigate the infrared identification of ZhuQin Formula and Atractylodes polysaccharides and its effect on immune function in immunocompromised mice. [Methods] In this experiment,the structure of polysaccharides was analyzed by Fourier transform infrared spectroscopy. The experiment was divided into the polysaccharide groups of high,medium and low dose of ZhuQin,the extraction group of ZhuQin,the polysaccharide group of Atractylodes,the positive drug group,the blank group and the model group. The model of immunosuppressed mice was established by intraperitoneal injection of cyclophosphamide. The carbon clearance index,immune organ index,serum hemolysin,spleen T and B lymphocyte transformation rate were determined. [Results]The results show that the polysaccharides have obvious absorption peaks of polysaccharides; Formula extracts and polysaccharides can enhance the immune function of immunosuppressive mice at a certain dose level,and the effect of formula polysaccharide is better than that of extract and single traditional Chinese medicine polysaccharides. [Conclusions] The results suggest that the polysaccharides of ZhuQin Formula and Atractylodes may be acidic polysaccharides containing pyran ring and furan ring. ZhuQin Formula polysaccharide may play an immunomodulatory role mainly by improving the specific immunity of the organism. 展开更多
关键词 ZhuQin Formula polysaccharide Atractylodes polysaccharide fourier transform infrared spectroscopy Immune function
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Characterization of polyhydroxyalkanoates synthesized in activated sludge using three carbon sources
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作者 张艳萍 《Journal of Beijing Institute of Technology》 EI CAS 2016年第3期429-434,共6页
Polyhydroxyalkanoates(PHAs)were synthesized in activated sludge using three types of carbon sources(sodium acetate,sodium propionate and sodium butyrate),and their characterization were studied.It was shown that the c... Polyhydroxyalkanoates(PHAs)were synthesized in activated sludge using three types of carbon sources(sodium acetate,sodium propionate and sodium butyrate),and their characterization were studied.It was shown that the content of PHA synthesized by microorganisms in activated sludge were different.The biggest synthetic amount up to 36.7% of VSS was obtained when sodium acetate was used as carbon source.The polymer yield was lower when using sodium propionate as the carbon source than when using others,with25.1% of VSS,while resulted in an increase of hydroxyvalerate(HV)units produced.The structure and thermal properties of extracted biopolymers were analyzed by scanning electron microscope(SEM),Fourier transform infrared spectroscopy(FTIR)and themogravimetry(TG). 展开更多
关键词 polyhydroxyalkanoates(PHAs) bio-polymer scanning electron microscope(SEM) fourier transform infrared spectroscopy(FTIR) activated sludge
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Analysis of Chemical Modification Mechanism and Rheological Properties of Polyphosphoric Acid Modified Asphalt
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作者 王岚 PEI Ke 李超 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2022年第5期876-884,共9页
In order to study the chemical modification mechanism and rheological properties of polyphosphoric acid (PPA)-modified asphalt,asphalt modified with different PPA contents were characterized by four-component test,ato... In order to study the chemical modification mechanism and rheological properties of polyphosphoric acid (PPA)-modified asphalt,asphalt modified with different PPA contents were characterized by four-component test,atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR).In the test,changes in asphalt chemical composition and colloidal structure were analyzed for different PPA contents,and infrared spectra were fitted with a Gaussian function.The reaction mechanism of PPA and matrix asphalt was also discussed.Based on dynamic shear rheometer (DSR) test and bending beam rheometer (BBR) test,rheological index G~*/sinδ and S/m were used to evaluate the modification effect of PPA on asphalt.The results show that,with an increase in PPA content,both large and small honeycomb structures increased in the three-dimensional topography seen in the atomic force microscope (AFM).In a certain space range,some of the micelles in the asphalt are connected each other to form interlocking skeleton structures,and locally form dense spatial network structures.The added PPA does not chemically react with the functional groups in the functional-group area of the infrared spectra (3 100-2 750 cm^(-1),1 800-1 330 cm^(-1)),and the structure is very stable.However,there is an obvious new absorption peak below 1 330 cm^(-1) in the fingerprint area,that is,the chemical reaction between PPA and the matrix asphalt generates a new compound,inorganic phosphate.Infrared spectra of PPA-modified asphalt with different contents were fitted by a Gaussian function,which makes up for the limitation that the absorption intensity information of each superimposed functional group cannot be obtained directly from the original infrared spectra.Results of this qualitative analysis were further verified by quantitative analysis.The addition of PPA can effectively improve the high and low-temperature performance of asphalt,and the lower the temperature is in the negative temperature zone,the more obvious the improvement is.When PPA content is more than 1%,the improvement of asphalt low-temperature performance is not obvious. 展开更多
关键词 polyphosphoric acid-modified asphalt dynamic shear rheometer(DSR)test fourier transform infrared spectroscopy(FTIR) chemical properties
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Efficacy and mechanism of methyl salicylate in the enhancement of skin delivery of herbal medicines
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作者 Jingyan Wang Xinyu Zhao +6 位作者 Jiajia Chen Xin Li Doudou Hao Tingting Li Kai Mei Yi Lan Qing Wu 《Journal of Traditional Chinese Medical Sciences》 2021年第4期336-342,共7页
Objective: To elucidate the molecular mechanism(s) by which methyl salicylate enhances the skin delivery of herbal ingredients with diverse lipophilicity.Methods: The toxicity of methyl salicylate on skin cell lines w... Objective: To elucidate the molecular mechanism(s) by which methyl salicylate enhances the skin delivery of herbal ingredients with diverse lipophilicity.Methods: The toxicity of methyl salicylate on skin cell lines was evaluated using the MTT assay. The Franz diffusion cell method was used to measure the permeability enhancing activities of methyl salicylate for five herbal ingredients with a range of lipophilicities. The interaction between methyl salicylate and the stratum corneum(SC) was observed by using an infrared spectroscopy technique. Moreover, the solubilities and SC-vehicle partition coefficient were determined to monitor the impact of methyl salicylate on the drug thermodynamic activities and partition into the SC layer, respectively.Results: Compared with azone(1-dodecylazacycloheptan-2-one), methyl salicylate showed lower toxicity to skin cells in terms of the IC50 values. The in vitro skin permeation studies showed that methyl salicylate could greatly improve the cumulative amounts or steady state flux of the selected model drugs with the exception of osthole, which indicated that methyl salicylate was prone to promote the skin delivery of hydrophilic drugs. The Fourier transform infrared spectroscopy studies revealed that methyl salicylate mainly interacted with SC lipids, leading to the disruption of the orderly arrangement of the SC.In addition, methyl salicylate had no obvious effect on the drug thermodynamic activity and partition into the SC.Conclusion: Methyl salicylate could effectively promote the skin delivery of relatively hydrophilic ingredients in externally used traditional Chinese medicines(TCM) without obvious cytotoxicity. 展开更多
关键词 Methyl salicylate Transdermal delivery Penetration enhancer Stratum corneum fourier transform infrared spectroscopy
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Long-term changes in mandibular bone microchemical quality after radiation therapy and underlying systemic malignancy:A pilot study
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作者 A.Palander H.Dekker +7 位作者 M.Hyvärinen L.Rieppo I.Lyijynen E.A.J.M.Schulten C.M.Ten Bruggenkate A.Koistinen A.Kullaa M.J.Turunen 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2021年第6期90-101,共12页
Radiation therapy(RT)is a treatment option for head and neck cancer(HNC),but 2%of RT patients may experience damage to the jawbone,resulting in osteoradionecrosis(ORN).The ORN can manifest years after RT exposure.Chan... Radiation therapy(RT)is a treatment option for head and neck cancer(HNC),but 2%of RT patients may experience damage to the jawbone,resulting in osteoradionecrosis(ORN).The ORN can manifest years after RT exposure.Changes in the local microchemical bone quality prior to the clinical manifestation of ORN could play a key role in ORN pathogenesis.Chemical bone quality can be analyzed using Fourier transform infrared spectroscopy(FTIR),that is applied to examine the effects of cancer,chemotherapy,and RT on the quality of human man-dibular bone.Cortical mandibular bone samples were harvested from dental implant beds of 23 individuals,i.e.,patients with surgically and radiotherapeutically treated HNC(RT-HNC,n=7),surgically and radiochemotherapeutically treated HNC(CH-RT-HNC,n=3),only surgically treated HNC(SRG-HNC,n=4),and healthy controls(n=9).Infrared spectra were acquired from two representative regions of interest in cortical mandibular bone.Spectral parameters,i.e.,mineral-to-matrix ratio(MM),carbonate-to-matrix ratio(CM),carbonate-to-phosphate ratio(CP),collagen maturity(cross-linking),crystallinity,acid phosphate substitu-tion(APS),and advanced glycation end products(AGEs),were analyzed for each sample.Amide I region of the CH-RT-HNC group differed from the control group in cluster analysis(p=0.02).Apart from a minor variation trend in collagen maturity(p=0.07),there were no other signif-icant differences between the groups.Thus,the effect of radiochemotherapy on mandibular bone composition should be further investigated.In future trials,this study design is potential when the effects of the cancer burden and different HNC treatment modalities on jawbone composition are studied,in order to reveal ORN pathogenesis. 展开更多
关键词 Mandibular bone radiation therapy fourier transform infrared spectroscopy
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Theoretical and Experimental Studies on the Isomeric Vibrations of (3,4-difluoro) Phenylhydroquinone
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作者 朱安峰 杨胜林 +2 位作者 彭为亚 李光 江建明 《Journal of Donghua University(English Edition)》 EI CAS 2011年第6期563-570,共8页
The (3,4-difluoro) Phenylhydroquinone (PHQ) have been successfully synthesized through the reaction of 3,4-difluoroaniline and 1,4-benzoquinone,and characterized by Fourier transform infrared spectroscopy(FTIR) and Ra... The (3,4-difluoro) Phenylhydroquinone (PHQ) have been successfully synthesized through the reaction of 3,4-difluoroaniline and 1,4-benzoquinone,and characterized by Fourier transform infrared spectroscopy(FTIR) and Raman spectroscopy.The ground-state geometries of the three PHQ isomers were distinguished using density functional theory(DFT) at the B3LYP/6-311G+(d,p) level without symmetry constraints.The results show that the predicted FTIR and Raman spectra are highly consistent with experimental spectra. 展开更多
关键词 (3 4-difluoro) Phenylhydroquinone (PHQ) fourier transform infrared spectroscopy (FTIR) RAMAN density functional theory (DFT)
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Preparation of Carboxymethyl Cellulose Fibers
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作者 刘树勇 闻林刚 +3 位作者 王志亮 沈端 李皆富 杨曙光 《Journal of Donghua University(English Edition)》 EI CAS 2016年第3期366-369,共4页
Carboxymethyl cellulose(CMC) fibers were produced by extruding the CMC solution into the metal salt coagulation bath and collected with a winding machine.It was found that copper chloride,ferric chloride,cerium chlori... Carboxymethyl cellulose(CMC) fibers were produced by extruding the CMC solution into the metal salt coagulation bath and collected with a winding machine.It was found that copper chloride,ferric chloride,cerium chloride,lanthanum chloride and aluminum nitrate solution could be used as coagulation bath to prepare CMC fibers,whereas the metal salt solutions,such as nickel chloride,zinc chloride,calcium chloride and magnesium chloride,could not.The fiber formation is due to the coordination between the carboxylates of CMC and metal ion.Fourier transform infrared spectroscopy(FTIR) was applied to studying the coordination mode of CMC and metal ion.The metal salt concentration,pH value and temperature of the coagulation bath affect the tenacity and elongation of the fiber.CMC fibers show good water uptake ability and can adsorb water more than 200% of its own weight.The mechanical behaviors of CMC fiber show dependence on environment humidity. 展开更多
关键词 FIBER carboxymethyl cellulose(CMC) fourier transform infrared spectroscopy(FT-IR) COORDINATION
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In situ Raman,FTIR,and XRD spectroscopic studies in fuel cells and rechargeable batteries 被引量:2
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作者 Fan Gao Xiang-Dong Tian +3 位作者 Jia-Sheng Lin Jin-Chao Dong Xiu-Mei Lin Jian-Feng Li 《Nano Research》 SCIE EI CSCD 2023年第4期4855-4866,共12页
As state-of-the-art electrochemical energy conversion and storage(EECS)techniques,fuel cells and rechargeable batteries have achieved great success in the past decades.However,modern societies’ever-growing demand in ... As state-of-the-art electrochemical energy conversion and storage(EECS)techniques,fuel cells and rechargeable batteries have achieved great success in the past decades.However,modern societies’ever-growing demand in energy calls for EECS devices with high efficiency and enhanced performance,which mainly rely on the rational design of catalysts,electrode materials,and electrode/electrolyte interfaces in EESC,based on in-deep and comprehensive mechanistic understanding of the relevant electrochemical redox reactions.Such an understanding can be realized by monitoring the dynamic redox reaction processes under realistic operation conditions using in situ techniques,such as in situ Raman,Fourier transform infrared(FTIR),and X-ray diffraction(XRD)spectroscopy.These techniques can provide characteristic spectroscopic information of molecules and/or crystals,which are sensitive to structure/phase changes resulted from different electrochemical working conditions,hence allowing for intermediates identification and mechanisms understanding.This review described and summarized recent progress in the in situ studies of fuel cells and rechargeable batteries via Raman,FTIR,and XRD spectroscopy.The applications of these in situ techniques on typical electrocatalytic electrooxidation reaction and oxygen reduction reaction(ORR)in fuel cells,on representative high capacity and/or resource abundance cathodes and anodes,and on the solid electrolyte interface(SEI)in rechargeable batteries are discussed.We discuss how these techniques promote the development of novel EECS systems and highlight their critical importance in future EECS research. 展开更多
关键词 in situ spectroscopy RAMAN fourier transform infrared spectroscopy(FTIR) X-ray diffraction(XRD) fuel cells rechargeable batteries
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