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Benchmarking calculations of excitation energies and transition properties with spectroscopic accuracy of highly charged ions used for the fusion plasma and astrophysical plasma
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作者 张春雨 王凯 +5 位作者 司然 李金晴 宋昌仙 吴思捷 严碧霜 陈重阳 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期179-193,共15页
Atomic radiative data such as excitation energies, transition wavelengths, radiative rates, and level lifetimes with high precision are the essential parameters for the abundance analysis, simulation, and diagnostics ... Atomic radiative data such as excitation energies, transition wavelengths, radiative rates, and level lifetimes with high precision are the essential parameters for the abundance analysis, simulation, and diagnostics in fusion and astrophysical plasmas. In this work, we mainly focus on reviewing our two projects performed in the past decade. One is about the ions with Z■30 that are generally of astrophysical interest, and the other one is about the highly charged krypton(Z = 36)and tungsten(Z = 74) ions that are relevant in research of magnetic confinement fusion. Two different and independent methods, namely, multiconfiguration Dirac–Hartree–Fock(MCDHF) and the relativistic many-body perturbation theory(RMBPT) are usually used in our studies. As a complement/extension to our previous works for highly charged tungsten ions with open M-shell and open N-shell, we also mainly focus on presenting and discussing our complete RMBPT and MCDHF calculations for the excitation energies, wavelengths, electric dipole(E1), magnetic dipole(M1), electric quadrupole(E2), and magnetic quadrupole(M2) transition properties, and level lifetimes for the lowest 148 levels belonging to the 3l3configurations in Al-like W61+. We also summarize the uncertainties of our systematical theoretical calculations, by cross-checking/validating our datasets from our RMBPT and MCDHF calculations, and by detailed comparisons with available accurate observations and other theoretical calculations. The data are openly available in Science Data Bank at https://doi.org/10.57760/sciencedb.10569. 展开更多
关键词 energy levels transition rates highly charged ions relativistic many-body perturbation theory(RMBPT) multi-configuration Dirac-Hartree-Fock(MCDHF) benchmarking calculations exci-tation energies spectroscopic accuracy
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Spectroscopic Measurements of Physiological Elements in Microdialysis Samples from Rat Brain,Flowering Plum Fruit and Pea 被引量:8
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作者 Hut Min MA Zhi Hua WANG +2 位作者 Yi ZENG Hut Wan HAN Guo Quan LIU(Institute of Chemistry,Chinese Academy of Sciences,Beijing 100080) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第3期243-246,共4页
IntroductionMicrodialysisisanimportantbioanalyticalsamplingtechnique,whichinvolvestheimplantationofasmallprobeofsemipermeablemembraneintothesubjecttobestudiedl.Themethodisminimallyinvasiveandverysuitableforstudyingpar... IntroductionMicrodialysisisanimportantbioanalyticalsamplingtechnique,whichinvolvestheimplantationofasmallprobeofsemipermeablemembraneintothesubjecttobestudiedl.Themethodisminimallyinvasiveandverysuitableforstudyingparameterssuchasphysiologicalelement... 展开更多
关键词 MICRODIALYSIS spectroscopic methods PHYSIOLOGICAL element analysis Calcium Magnesium copper
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Valence Bond Study of Dissociation Behavior and Spectroscopic Constants for the Ground States of LiF and NaF 被引量:3
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作者 CAO Ze xing ** , WU Wei and ZHANG Qian er (Department of Chemistry, State Key Laboratory for Physical Chemistry of the Surface Science, and Institute of Physical Chemistry, Xiamen University, Xiamen, 361005) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1998年第3期75-81,共7页
IntroductionThealkalihalidediatomicmoleculesprovideatypicalcurvecrosingproblem[1].Theoutstandingnonadiabatic... IntroductionThealkalihalidediatomicmoleculesprovideatypicalcurvecrosingproblem[1].Theoutstandingnonadiabaticbehaviorofthechem... 展开更多
关键词 VBSCF spectroscopic constant Curve CROSSING
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Raman Spectroscopic Study of Silicon Nanopowders 被引量:3
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作者 S.M.Scholz J.Dutta and H.Hofmann(Lab. de Technologie des Poudres, Departement de Materiaux, Ecole Polytechnique Federale de Lausanne,1015 Lausanne, Switzerland)H.Hofmeister (Max-Planck-Institut fur Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1997年第4期327-332,共6页
Vibrational properties of silicon nanopowders are discussed with reference to Raman spectroscopic measurements. The powders were produced in a low pressure rf plasma from the cluster induced agglomeration of positive ... Vibrational properties of silicon nanopowders are discussed with reference to Raman spectroscopic measurements. The powders were produced in a low pressure rf plasma from the cluster induced agglomeration of positive ions formed during the dissociation of silane. Influence of thermal treatment and the crystallization phenomena of the powder were studied. Raman spectroscopic measurements reveal size quantization effects for the particles as well as the existence of partially ordered regions in the apparently amorphous primary particles. The crystalline and amorphous volume fraction in the material were calculated from the relative spectraI intensities. The results obtained in these experiments are consistent with the observations from recent high resolution transmission electron microscopy studies of these 展开更多
关键词 HRTEM CM NM Raman spectroscopic Study of Silicon Nanopowders
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Interaction of repaglinide with bovine serum albumin:Spectroscopic and molecular docking approaches 被引量:2
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作者 Suma K.Pawar Seetharamappa Jaldappagari 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2019年第4期274-283,共10页
Repaglinide (RPG) regulates the amount of glucose by stimulating the pancreas to release insulin in the blood. In view of its biological importance, we have examined the interaction between RPG and a model protein, bo... Repaglinide (RPG) regulates the amount of glucose by stimulating the pancreas to release insulin in the blood. In view of its biological importance, we have examined the interaction between RPG and a model protein, bovine serum albumin (BSA) employing various spectroscopic, electrochemical and molecular docking methods. Fluorescence spectra of BSA were recorded in the presence and absence of RPG in phosphate buffer of pH 7.4. Fluorescence intensity of BSA was decreased upon the addition of increased concentrations of RPG, indicating the interaction between RPG and BSA. Stern-Volmer quenching analysis results revealed that RPG quenched the intensity of BSA through dynamic quenching mechanism. This was further confirmed from the time-resolved fluorescence measurements. The binding constant as calculated from the spectroscopic and voltammetric results was observed to be in the order of 104M-1 at 298 K, suggesting the moderate binding affinity between RPG and BSA. Competitive experimental results revealed that the primary binding site for RPG on BSA was site II. Absorption and circular dichroism studies indicated the changes in the secondary structure of BSA upon its interaction with RPG. Molecular simulation studies pointed out that RPG was bound to BSA in the hydrophobic pocket of site II. 展开更多
关键词 BSA-RPG INTERACTION spectroscopic investigation Molecular DOCKING
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An integrated spectroscopic strategy to trace the geographical origins of emblic medicines: Application for the quality assessment of natural medicines 被引量:2
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作者 Luming Qi Furong Zhong +3 位作者 Yang Chen Shengnan Mao Zhuyun Yan Yuntong Ma 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2020年第4期356-364,共9页
Emblic medicine is a popular natural source in the world due to its outstanding healthcare and therapeutic functions.Our preliminary results indicated that the quality of emblic medicines might have an apparent region... Emblic medicine is a popular natural source in the world due to its outstanding healthcare and therapeutic functions.Our preliminary results indicated that the quality of emblic medicines might have an apparent regional variation.A rapid and effective geographical traceability system has not been designed yet.To trace the geographical origins so that their quality can be controlled,an integrated spectroscopic strategy including spectral pretreatment,outlier diagnosis,feature selection,data fusion,and machine learning algorithm was proposed.A featured data matrix(245220)was successfully generated,and a carefully adjusted RF machine learning algorithm was utilized to develop the geographical traceability model.The results demonstrate that the proposed strategy is effective and can be generalized.Sensitivity(SEN),specificity(SPE)and accuracy(ACC)of 97.65%,99.85%and 97.63%for the calibrated set,as well as 100.00%predictive efficiency,were obtained using this spectroscopic analysis strategy.Our study has created an integrated analysis process for multiple spectral data,which can achieve a rapid,nondestructive and green quality detection for emblic medicines originating from seventeen geographical origins. 展开更多
关键词 Emblic medicine Quality assessment Geographical traceability spectroscopic analysis process
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Fourier Transform Infrared Spectroscopic Characterization of Kaolinite from Assam and Meghalaya, Northeastern India 被引量:13
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作者 Bhaskar J. Saikia Gopalakrishnarao Parthasarathy 《Journal of Modern Physics》 2010年第4期206-210,共5页
This study demonstrates the Fourier transform infrared (FTIR) spectroscopic characterization of natural kaolinite from north-eastern India. The compositional and structural studies were carried out at room temperature... This study demonstrates the Fourier transform infrared (FTIR) spectroscopic characterization of natural kaolinite from north-eastern India. The compositional and structural studies were carried out at room temperature by using X-ray fluorescence (XRF), electron microprobe (EPMA) analyses and Fourier transform infrared (FTIR) spectroscopic techniques. The main peaks in the infrared spectra reflected Al-OH, Al-O and Si-O functional groups in the high frequency stretching and low frequency bending modes. Few peaks of infrared spectra inferred to the interference peaks for quartz as associated minerals. The present study demonstrates usefulness of the spectroscopic techniques in determining quality and crystalline nature of kaolinite from the Assam and Meghalaya, northeastern India. 展开更多
关键词 KAOLINITE spectroscopic Characterization FTIR
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In-depth investigation on physicochemical and thermal properties of magnesium(Ⅱ) gluconate using spectroscopic and thermoanalytical techniques 被引量:1
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作者 Mahendra Kumar Trivedi Neena Dixit +2 位作者 Parthasarathi Panda Kalyan Kumar Sethi Snehasis Jana 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2017年第5期332-337,共6页
Magnesium gluconate is a classical organometallic pharmaceutical compound used for the prevention and treatment of hypomagnesemia as a source of magnesium ion. The present research described the in-depth study on soli... Magnesium gluconate is a classical organometallic pharmaceutical compound used for the prevention and treatment of hypomagnesemia as a source of magnesium ion. The present research described the in-depth study on solid state properties viz. physicochemical and thermal properties of magnesium gluconate using sophisticated analytical techniques like Powder X-ray diffraction(PXRD), particle size analysis(PSA),Fourier transform infrared(FT-IR) spectrometry, ultraviolet–visible(UV–Vis) spectroscopy, thermogravimetric analysis(TGA)/differential thermogravimetric analysis(DTG), and differential scanning calorimetry(DSC).Magnesium gluconate was found to be crystalline in nature along with the crystallite size ranging from 14.10 to47.35 nm. The particle size distribution was at d(0.1)=6.552 μm, d(0.5)=38.299 μm, d(0.9)=173.712 μm and D(4,3)=67.122 μm along with the specific surface area of 0.372 m^2/g. The wavelength for the maximum absorbance was at 198.0 nm. Magnesium gluconate exhibited 88.51% weight loss with three stages of thermal degradation process up to 895.18 °C from room temperature. The TGA/DTG thermograms of the analyte indicated that magnesium gluconate was thermally stable up to around 165 °C. Consequently, the melting temperature of magnesium gluconate was found to be 169.90 °C along with the enthalpy of fusion of 308.7 J/g.Thus, the authors conclude that the achieved results from this study are very useful in pharmaceutical and nutraceutical industries for the identification, characterization and qualitative analysis of magnesium gluconate for preformulation studies and also for developing magnesium gluconate based novel formulation. 展开更多
关键词 MAGNESIUM GLUCONATE Solid state properties Particle size ANALYSIS Thermal ANALYSIS spectroscopic ANALYSIS
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Fourier Transform Infrared Spectroscopic Studies in Flotation 被引量:1
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作者 龚文琪 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2001年第1期63-69,共7页
Fourier transform infrared (FTIR) spectroscopy has been extensively employed In flotation research. The work done by the author and co-workers has been reported. A comparison has been made among the different FTIR spe... Fourier transform infrared (FTIR) spectroscopy has been extensively employed In flotation research. The work done by the author and co-workers has been reported. A comparison has been made among the different FTIR specfroscopic techniques, e.g. , transmission FTIR spectroscopy, diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy, and attenuated total reflectance (ATR) FTIR spectroscopy. FTIR spectroscopy has been used to study the mechanism of interaction between the collector and the surfaces of different minerals, the mechanism of action of the depressant in improving the selectivity of flotation, and the mechanism of adsorption of the polymeric modifying reagent on mineral surfaces. The interaction between particles in mineral suspension has also been studied by FTIR spectroscopy. 展开更多
关键词 FLOTATION INFRARED spectroscopic STUDY FOURIER TRANSFORM
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Raman and Infrared Spectroscopic Investigation of Some Hydrous LnTPPTS Complexes(Ln=La,Sm) 被引量:1
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作者 Tian Bingshou,Yao Junzhi,Chen Yuanyin Department of Chemistry,Wuhan University,Wuhan 430072,China 《Wuhan University Journal of Natural Sciences》 CAS 1997年第2期75-78,共4页
RamanandInfraredSpectroscopicInvestigationofSomeHydrousLnTPPTSComplexes(Ln=La,Sm)ChenZhenhua,ChenXinlan,Tian... RamanandInfraredSpectroscopicInvestigationofSomeHydrousLnTPPTSComplexes(Ln=La,Sm)ChenZhenhua,ChenXinlan,TianBingshou,HeJiping... 展开更多
关键词 ferrocenylselenoethers complex spectroscopic property STEREODYNAMICS
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Spectroscopic and macroscopic studies of the adsorption of arsenate and phosphate on polynuclear aluminum organomineral precipitates 被引量:1
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作者 Liu, Jing Zhao, Fenghua 《Chinese Journal Of Geochemistry》 EI CAS 2011年第2期264-269,共6页
Aluminum organic coprecipitates play important roles in the transport of oxyanions in soil environment.A new polynuclear aluminum organomineral precipitate(Al13-oxalate precipitate) was prepared to investigate the ads... Aluminum organic coprecipitates play important roles in the transport of oxyanions in soil environment.A new polynuclear aluminum organomineral precipitate(Al13-oxalate precipitate) was prepared to investigate the adsorption behavior of arsenate and phosphate on noncrystalline aluminum precipitates.Important thermodynamic parameters for adsorption reaction were evaluated using macroscopic adsorption data and equations.The result showed that,the adsorption reaction basically is a diffusion process.FTIR spectroscopic studies have provided evidence for the formation of two different types of complexes in substrate,protonated bidentate and deprotonated bidentate complexes at pH 4 and pH≥6,respectively.The classic competitive adsorption and XPS studies both indicated that phosphate has stronger chemical interaction with substrate than arsenate.The findings of XPS studies revealed that the precipitate substrate can act as Lewis acid when adsorbing oxyanions. 展开更多
关键词 organomineral precipitate competitive adsorption spectroscopic study
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Equidistant combination wavelength screening and step-by-step phase-out method for the near-infrared spectroscopic analysis of serum urea nitrogen 被引量:1
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作者 Yihui Yang Fenfen Lei +3 位作者 Jing Zhang Lijun Yao Jiemei Chen Tao Pan 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2019年第6期85-96,共12页
We applied near-infrared(NIR)spectroscopy with chemometrics for the rapid and reagent-fee analysis of serum urea nitrogen(SUN).The modeling is based on the average effect of multiple sample partitions to achieve param... We applied near-infrared(NIR)spectroscopy with chemometrics for the rapid and reagent-fee analysis of serum urea nitrogen(SUN).The modeling is based on the average effect of multiple sample partitions to achieve parameter selection with stability.A multiparameter optimization platform with Norris derivative filter-partial least squares(Norris-PLS)was developed to select the most suitable mode(d=2,s=33,g=15).Using equidistant combination PLS(EC-PLS)with four parameters(initial wavelength I,number of wavelengths N,number of wavelength gaps G and latent variables LV),we performed wavelength screening after eliminating high-absorption wavebands.The optimal EC-PLS parameters were I=1228 nm,N=26,G=16 and LV=12.The root-mean square error(SEP),correlation coefficient(R_(p))for prediction and ratio of performance-to-deviation(RPD)for validation were 1.03 mmol L^(-1),0.992 and 7.6,respectively.We proposed the wavelength step-by-step phase-out PLS(WSP-PLS)to remove redun-dant wavelengths in the top 100 EC-PLS models with improved prediction performance.The combination of 19 wavelengths was identifed as the optimal model for SUN.The SEP,Rp and RPD in validation were 1.01 mmol L^(-1),0.992 and 7.7,respectively.The prediction effect and wavelength complexity were better than those of EC-PIS.Our results showed that NIR spectroscopy combined with the EC-PLS and WSP-PLS methods enabled the high-precision analysis ofSUN.WSP-PLS is a secondary optimization method that can further optimize any wavelength moc odel obtained through other continuous or discrete strategies to establish a simple and better model. 展开更多
关键词 Serum urea nitrogen near infrared spectroscopic analysis Norris derivative filter equidistant combination wavelength screening wavelength step-by-step phase-out
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A star-based method for precise wavelength calibration of the Chinese Space Station Telescope(CSST) slitless spectroscopic survey 被引量:1
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作者 Hai-Bo Yuan Ding-Shan Deng Yang Sun 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第3期235-242,共8页
The Chinese Space Station Telescope(CSST)spectroscopic survey aims to deliver high-quality low-resolution(R>200)slitless spectra for hundreds of millions of targets down to a limiting magnitude of about 21 mag,dist... The Chinese Space Station Telescope(CSST)spectroscopic survey aims to deliver high-quality low-resolution(R>200)slitless spectra for hundreds of millions of targets down to a limiting magnitude of about 21 mag,distributed within a large survey area(17500 deg2)and covering a wide wavelength range(255-1000 nm by three bands GU,GV,and GI).As slitless spectroscopy precludes the usage of wavelength calibration lamps,wavelength calibration is one of the most challenging issues in the reduction of slitless spectra,yet it plays a key role in measuring precise radial velocities of stars and redshifts of galaxies.In this work,we propose a star-based method that can monitor and correct for possible errors in the CSST wavelength calibration using normal scientific observations,taking advantage of the facts that(ⅰ)there are about ten million stars with reliable radial velocities now available thanks to spectroscopic surveys like LAMOST,(ⅱ)the large field of view of CSST enables efficient observations of such stars in a short period of time,and(ⅲ)radial velocities of such stars can be reliably measured using only a narrow segment of CSST spectra.We demonstrate that it is possible to achieve a wavelength calibration precision of a few km s^(-1) for the GU band,and about 10 to 20 kms^(-1) for the GV and GI bands,with only a few hundred velocity standard stars.Implementations of the method to other surveys are also discussed. 展开更多
关键词 methods:data analysis methods:statistical techniques:spectroscopic techniques:radial velocities stars:fundamental parameters stars:kinematics and dynamics
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Scanning Tunneling Microscopic and Scanning Tunneling Spectroscopic Studies of Nanocrystalline CdSe Thin Film 被引量:1
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作者 Yuan LIN Rui Feng LIN +2 位作者 Xiao Wen Zhou Jing Bo Zhang Xu Rui Xiao(Institute of Photographic Chemistry, The Chinese Academy of Sciences, Bejing,100101) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第9期831-832,共2页
Nanocrystalline CdSe thin film prepared by chemical solution deposition was imaged in air with a scaninng tunneling microscope(STM). Scanning tunneling current spectroscopy(STS) was taken at a fixed tip - Sample separ... Nanocrystalline CdSe thin film prepared by chemical solution deposition was imaged in air with a scaninng tunneling microscope(STM). Scanning tunneling current spectroscopy(STS) was taken at a fixed tip - Sample separation. Tunneling currnt(i) - voltage(v) curve and differential conductance spectrum show an n-type schottky rectifying behaviour and yteld a direct measure of band gap energy. An increase of bandgap energy (1.8 - 2.1eV) was measured indicating energy quantization of this particular thin film. 展开更多
关键词 Thin CDSE Scanning Tunneling Microscopic and Scanning Tunneling spectroscopic Studies of Nanocrystalline CdSe Thin Film
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Structures, Lipophilicity, Dipole Moments, Acidity and Spectroscopic Properties of Non-Steroidal Anti-Inflammatory Drugs Diclofenac, Bromfenac and Amfenac: A Theoretical Study 被引量:1
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作者 Assoma Amon Benjamine Bede Affoué Lucie +1 位作者 Yapo Kicho Denis Bamba El Hadji Sawaliho 《Computational Chemistry》 2019年第4期95-105,共11页
This work is a contribution of theoretical chemistry to the classification of some non-steroidal anti-inflammatory drugs (NSAIDs). Indeed, research on the efficacy of NSAIDs has shown that no NSAID is recognized as th... This work is a contribution of theoretical chemistry to the classification of some non-steroidal anti-inflammatory drugs (NSAIDs). Indeed, research on the efficacy of NSAIDs has shown that no NSAID is recognized as the most efficient anti-inflammatory drug. We have made a theoretical study of diclofenac, bromfenac and amfenac, in order to compare their efficacy from some physicochemical properties. To do this, we used the DFT and TD-DTF methods at the B3LYP/6-311+G(d, p) level theory. The lipophilicity study shows that diclofenac and bromfenac are very lipophilic. Acidity study shows that diclofenac is more acid than bromfenac and amfenac. The results from molecular orbital and the TD-DFT calculations reveal that for the three NSAIDs, the lowest energy transition is due to the excitation from HOMO to LUMO. The absorption energy corresponding to H→L transition is comparable with the energy gap value. Our findings have shown that bromfenac is more reactive than amfenac, which is more reactive than diclofenac. 展开更多
关键词 DICLOFENAC Bromfenac Amfenac DFT spectroscopic Properties
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Closed/Open-Cell Photoacoustic Imaging for Spectroscopic Measurements 被引量:1
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作者 Tsutomu Hoshimiya 《Journal of Applied Mathematics and Physics》 2016年第8期1470-1474,共6页
Photoacoustic imaging using a closed photoacoustic cell and an open photoacoustic cell with gas- microphone detection scheme was described. R/G/B LED light sources were used for the closed photoacoustic (PA) cell conf... Photoacoustic imaging using a closed photoacoustic cell and an open photoacoustic cell with gas- microphone detection scheme was described. R/G/B LED light sources were used for the closed photoacoustic (PA) cell configuration. The colored specimen enclosed in a PA cell was imaged with R/G/B color light sources, and an image restored from the inverted PA images was compared with the original image. For open cell configuration, an open PA cell using a spheroidal acoustic resonator was applied to measure the amount of large-sized colored specimens. A calibration curve for a food red dye was obtained that apparently showed the ability of the present scheme to measure as a spectroscopic measurement tool. 展开更多
关键词 PHOTOACOUSTIC IMAGING spectroscopic Calibration Curve Color Restoration
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Preparation and Spectroscopic of Vanadyl(Ⅱ) Vitamin D3 Amino Acid Mixed Complexes as Insulin Mimetic Drug
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作者 Enas Aljuhani Amnah M.A.Alsuhaibani +3 位作者 A.M.El-Di damony N.Hassan Sameh Abo Taleb Moamen S.Refat 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2019年第7期2316-2324,共9页
A new six intraperitoneal injection insulin-mimetic vanadyl(Ⅱ) compounds [(VD3^-1)(VO^+2)(AAn^-1)](where(n=1~6);AA1=isoleucine, AA2=threonine, AA3=proline, AA4=phenylalanine, AA5=lysine and AA6=glutamine) were synthe... A new six intraperitoneal injection insulin-mimetic vanadyl(Ⅱ) compounds [(VD3^-1)(VO^+2)(AAn^-1)](where(n=1~6);AA1=isoleucine, AA2=threonine, AA3=proline, AA4=phenylalanine, AA5=lysine and AA6=glutamine) were synthesized by the chemical reactions between vitamin D3(VD3), VOSO4 and amino acids(AAn) with equal molar ratio 1∶1∶1 in neutralized media. The structures of these complexes were elucidated by spectroscopic methods like, infrared and solid reflectance spectroscopes. Magnetic moments and electronic spectra reveal square pyramid geometrical structure of the complexes. The infrared spectra assignments of these complexes revealed that the chelation towards vanadyl(Ⅳ) ions existed via deprotonation of the hydroxyl group of VD3 drug ligand and so amino acids act as bidentate ligand via N-amino and O-carboxylate groups. The anti-diabetic efficiency of these complexes were evaluated against streptozotocin induced diabetic male albino rats. 展开更多
关键词 INSULIN alternative Diabetes DRUG VO^2+ ion Vitamin D3 Amino acid spectroscopic
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Spectroscopic Characterization of Mo-Co-S and Mo-Fe-S Complexes-derived Catalysts for Desulfurization and Denitrification
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作者 LIN Guo-dong, LIU Yu-da, YANG Yi-quan and ZHANG Hong-bin(Department of Chemistry and Institute, of Physical Chemistry,Xiamen University, Xiamen, 361005) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1992年第3期188-195,共8页
The characteristic studies, by means of LR, UV-Vis and XPS spectroscopies, of the preparation process of Mo-Co-S and Mo-Fe-S catalysts for HDS and HDN, derived from (NH4)2MoS4-CoCl2 and (NH4)2MoS4-FeCl2 complexes supp... The characteristic studies, by means of LR, UV-Vis and XPS spectroscopies, of the preparation process of Mo-Co-S and Mo-Fe-S catalysts for HDS and HDN, derived from (NH4)2MoS4-CoCl2 and (NH4)2MoS4-FeCl2 complexes supported on γ-Al2O3, respectively, indicate that the catalytically essential moiety on the surface of the catalysts is dominantly some sulfido-bimetallic species with such a structural unit (M’ =Co or Fe), and both Co and Fe, served as promoters, can donate electrons to Mo probably via bridging-S. The nature of active-sites and the mechanism of promotion are discussed according to the results. 展开更多
关键词 Mo-Co-S and Mo-Fe-S CATALYSTS DESULFURIZATION and DENITRIFICATION spectroscopic characterization
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SPECTROSCOPIC STUDIES OF SEVERAL MESO-SUBSTITUTED ZINC TETRABENZOPORPHYRINS
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作者 Ling Zhi HU Duo Yuan WANG Institute of Photographic Chemistry,Academia Sinica,Beijing 100101Zhong Xing JIANG Zhang Ping CHEN Xuan Jie WU Department of Chemistry,Wuhan University,Wuhan 430072 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第8期645-648,共4页
The electronic spectroscopic properties of severalmeso-substituted zinc tetrabenzoporphyrins(ZnTBP,ZnTMTBP,ZnTPTBP,ZnTTTBP and ZnTNTBP)have been investigated intoluene.The lifetimes determined showed that the fluoresc... The electronic spectroscopic properties of severalmeso-substituted zinc tetrabenzoporphyrins(ZnTBP,ZnTMTBP,ZnTPTBP,ZnTTTBP and ZnTNTBP)have been investigated intoluene.The lifetimes determined showed that the fluorescenceof these compounds decay with good double exponentials. 展开更多
关键词 spectroscopic SUBSTITUTED decay TOLUENE SINGLET BENZENE RADIATIVE minutes oscillator normalized
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SPECTROSCOPIC PROPERTIES OF THE PHYCOBILINS AND THEIR DERIVATIVES
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作者 Ling Jiang CHENG Li Jin JIANG Institute of Photographic Chemistry,Chinese Academy of Sciences,Beijing 100101 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第7期589-592,共4页
The UV-VIS spectroscopic studies of phycoerythrobilin dimethyl ester,phycocyanobilin dimethyl ester and their derivatives indicate that shortening of theconjugative systems induces hypsochromic shifts in wavelength an... The UV-VIS spectroscopic studies of phycoerythrobilin dimethyl ester,phycocyanobilin dimethyl ester and their derivatives indicate that shortening of theconjugative systems induces hypsochromic shifts in wavelength and increases in molarextinction coefficients in visible part;both zinc ion coordination and acetic acidtreatment induce bathochromic effects for the phycobilins and their derivatives. 展开更多
关键词 SHORTENING spectroscopic VISIBLE acetic ANALOGUES Bishop Biophys regardless Physiol SORPTION
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