The Fourier transform spectrometer(FTS)is a core instrument for solar observation with high spectral resolution,especially in the infrared.The Infrared System for the Accurate Measurement of Solar Magnetic Field(AIMS)...The Fourier transform spectrometer(FTS)is a core instrument for solar observation with high spectral resolution,especially in the infrared.The Infrared System for the Accurate Measurement of Solar Magnetic Field(AIMS),working at 10-13μm,will use an FTS to observe the solar spectrum.The Bruker IFS-125 HR,which meets the spectral resolution requirement of AIMS but simply equips with a point source detector,is employed to carry out preliminary experiment for AIMS.A sun-light feeding experimental system is further developed.Several experiments are taken with them during 2018 and 2019 to observe the solar spectrum in the visible and near infrared wavelength,respectively.We also proposed an inversion method to retrieve the solar spectrum from the observed interferogram and compared it with the standard solar spectrum atlas.Although there is a wavelength limitation due to the present sun-light feeding system,the results in the wavelength band from 0.45-1.0μm and 1.0-2.2μm show a good consistency with the solar spectrum atlas,indicating the validity of our observing configuration,the data analysis method and the potential to work in longer wavelength.The work provided valuable experience for the AIMS not only for the operation of an FTS but also for the development of its scientific data processing software.展开更多
The miniaturization of spectrometer opens a new application area with real-time and on-site measurements.The Fourier transform spectrometer(FTS)is much attractive considering its particular advantages among the approa...The miniaturization of spectrometer opens a new application area with real-time and on-site measurements.The Fourier transform spectrometer(FTS)is much attractive considering its particular advantages among the approaches.This paper reviews the current status of micro FTS in worldwide and describes its developments;In addition,analyzed are the key problems in designing and fabricating FTS to be settled during the miniaturization.Finally,a novel model of micro FTS with no moving parts is proposed and analyzed,which may provide new concepts for the design of spectrometers.展开更多
Optical frequency combbased Fourier transform spectroscopy has the features of broad spectral bandwidth,high sensitivity,andmultiplexed trace gas detection,which has valuable application potential in the fields of pre...Optical frequency combbased Fourier transform spectroscopy has the features of broad spectral bandwidth,high sensitivity,andmultiplexed trace gas detection,which has valuable application potential in the fields of precision spectroscopy and trace gas detection.Here,we report the development of a mid-infrared Fourier transform spectrometer based on an optical frequency comb combined with a Herriott-type multipass cell.Using this instrument,the broadband absorption spectra of several important molecules,including methane,acetylene,water molecules and nitrous oxide,are measured by near real-time data acquisition in the 2800-3500 cm^(-1)spectral region.The achieved minimum detectable absorption of the instrument is 4.4×10^(-8)cm^(-1)·Hz^(-1/2)per spectral element.Broadband spectra of H_(2)0 are fited using the Voigt profile multispectral fitting technique and the consistency of the concentration inversion is 1%.Our system also enables precise spectroscopic measurements,and it allows the determination of the spectral line positions and upper state constants of N_(2)O in the(0002)-(1000)band,with results in good agreement with those reported by Toth[Appl.Opt.30,5289(1991)].展开更多
Bio-oil is a new liquid fuel produced by fast pyrolysis,which is a promising technology to convert bio-mass into liquid. Pyrolytic lignin extracted from bio-oil,a fine powder,contributes to the instability of bio-oil....Bio-oil is a new liquid fuel produced by fast pyrolysis,which is a promising technology to convert bio-mass into liquid. Pyrolytic lignin extracted from bio-oil,a fine powder,contributes to the instability of bio-oil. The paper presents the structural features of three kinds of pyrolytic lignin extracted from bio-oil with different methods(WIF,HMM,and LMM) . The pyrolytic lignin samples are characterized by Fourier transform infrared spectrometer(FTIR) and X-ray photoelectron spectroscopy(XPS) . FTIR data indicate that the three pyrolytic lignin samples have similar functional groups,while the absorption intensity is different,and show characteristic vibra-tions of typical lignocellulosic material groups O H(3340-3380 cm-1) ,C H(2912-2929 cm-1) and C O(1652-1725 cm-1) . Comparison in the region(3340-3380 cm-1) indicates that WIF has more O H stretch groups than HMM and LMM. The carbon spectra are fitted to four peaks:C1,C C or C H,BE 283.5 eV;C2,C OR or C OH,BE 284.5-285.8 eV;C3,C O or HO C OR,BE 286.10-287.10 eV;C4,O C O,BE 287.5-287.7 eV. The absence of C1,C C or C H indicates the dominant polymerization structure of aro-matic carbon in pyrolytic lignin samples. For HMM and WIF,C2a and C2b can not be separated,so there is no free hydroxyl group in the samples. The oxygen peaks are also fitted to four peaks:O1,OH,BE = 530.3 eV;O2,RC O,BE 531.45-531.72 eV;O3,O C O,BE = 532.73-533.74 eV;O4,H2O,BE 535 eV. The absence of O1 and O4 indicates that little hydroxyl groups and adsorbed water are present in the samples.展开更多
Photooxidation reaction of toluene in smog chamber systems was initiated by the UV radiation of tolucne/CH5ONO/NOx mixtures. The products of the photooxidation reaction of toluene and its subsequent reactions were ana...Photooxidation reaction of toluene in smog chamber systems was initiated by the UV radiation of tolucne/CH5ONO/NOx mixtures. The products of the photooxidation reaction of toluene and its subsequent reactions were analyzed directly utilizing Fourier transform infrared spectrometer （FTIR）. Detailed assignments to FTIR spectrum of gas-phase products were given. The information of some important functional groups in the products, such as, carbonyl groups （C-O）, hydroxyl groups （-OH）, carboxylic acid （- COOH）, C-C bonding, N O bonding and C-H bonding （C H）, was got from this analysis. These results were compared to those analyzed by aerosol time of flight mass spectrometer （ATOFMS）. It was found that there are some differcnccs between FTIR analysis of gas-phase products and that of particle-phase, for example, the products with carbonyl groups, which were connected to unsaturated chemical bonds, was relatively higher in the gas phase, while kctoncs, aldehydes, carboxylic acid and organonitrates were the dominant functional groups in the aerosol-phase reaction products. The possible reaction pathways of some important products in the gas phase were also discussed.展开更多
Cosmic-microwave-background(CMB)B-mode measurements may reveal primordial gravitational waves from the earliest phases of the Big Bang.As the first CMB experiment in the northern hemisphere,the Ali CMB polarization te...Cosmic-microwave-background(CMB)B-mode measurements may reveal primordial gravitational waves from the earliest phases of the Big Bang.As the first CMB experiment in the northern hemisphere,the Ali CMB polarization telescope(Ali CPT)will carry out measurements of this kind at Ali(Nagri)in Tibet.It is therefore of particular importance to understand the terahertz atmospheric transmission at this site.Here we report on the measurement results for three consecutive seasons with a Fourier transform spectrometer(FTS)spanning a wide frequency range from 0.75 to 14 THz.The zenith median precipitable-watervapor(PWV)is found to be as low as 1 mm at the Ali CPT site,which appears as good as those CMB B-mode measurement sites in the southern hemisphere such as Chile's Atacama Desert.展开更多
In order to correctly use the column-averaged atmospheric COdry-air mole fraction(XCO) data in the COflux studies, XCOmeasurements retrieved from the Orbiting Carbon Observatory-2(OCO-2) in 2015 were compared with tho...In order to correctly use the column-averaged atmospheric COdry-air mole fraction(XCO) data in the COflux studies, XCOmeasurements retrieved from the Orbiting Carbon Observatory-2(OCO-2) in 2015 were compared with those obtained from the global ground-based high-resolution Fourier Transform Spectrometer(FTS) participating in the Total Carbon Column Observing Network(TCCON). The XCOretrieved from three observing modes adopted by OCO-2, i.e., nadir, target, and glint, were separately validated by the FTS measurements at up to eight TCCON stations located in different areas. These comparisons show that OCO-2 glint mode yields the best qualitative estimations of COconcentration among the three operational approaches. The overall results regarding the glint mode show no obvious systematic biases. These facts may indicate that the glint concept is appropriate for not only oceans but also land regions. Negative systematic biases in nadir and target modes have been found at most TCCON sites. The standard deviations of XCOretrieved from target and nadir modes within the observation period are similar, and larger than those from glint mode. We also used the FTS site in Beijing, China, to assess the OCO-2 XCOin 2016. This site is located in a typical urban area, which has been absent in previous studies. Overall, OCO-2 XCOagrees well with that from FTS at this site. Such a study will benefit the validation of the newly launched TanSat products in China.展开更多
A zwitterionic nanofiber film was constructed through combining zwitterionic polymer with anodic aluminum oxide template for anti-adhering typical marine corrosive microorganisms,i.e.Pseudomonas aeruginosa,Desulfovibr...A zwitterionic nanofiber film was constructed through combining zwitterionic polymer with anodic aluminum oxide template for anti-adhering typical marine corrosive microorganisms,i.e.Pseudomonas aeruginosa,Desulfovibrio vulgaris and Chaetoceros muelleri.Results showed that the fabricated zwitterionic polymers film has fibrous nanostructure with uniform distribution and super hydrophilia.This film has wide anti-adhering properties,and it can effectively reduce the attachment of these three microorganisms by more than 99%.Moreover,the adhesion of extracellular polymeric substances secreted from these three microorganisms are also inhibited,which is one reason for the fabricated nanofiber film with antiadhesion characteristic of microorganisms.This research provides valuable information for solving the problem of microbial adhesion on metal surfaces in the marine environment.展开更多
Objective： To determine the pyrolysis characteristics of calcined and processed calamine, qualitatively and quantitatively compare the contents of related elements, morphology and functional groups of the pyrolysis p...Objective： To determine the pyrolysis characteristics of calcined and processed calamine, qualitatively and quantitatively compare the contents of related elements, morphology and functional groups of the pyrolysis products dried at different heating temperatures and explore the critical temperature and the optimal drying temperature for the process of calamine with Huanglian Decoction（HLD, 黄连汤） and San Huang Decoction（SHD, 三黄汤）. Methods： Pyrolysis products were prepared by programmable and constantly heating the calcined and processed calamine to or at different heating temperatures. Thermogravimetry（TG） was used to test their pyrolysis characteristics. Fourier transform infrared spectroscopy and scanning electron microscopeenergy dispersive spectrometer were used to determine their morphology, functional groups and element contents. Page model was used to investigate the constant drying kinetics of processed calamine. Results： The adding of HLD or SHD to calcined calamine（CC） can slow its weight loss in drying pyrolysis process. The temperature ranges where HLD and SHD can affect its weight loss were 65–150 ℃ and 74–180 ℃, respectively. The drying temperature was optimized as 90 ℃. The drying kinetic for the processed calamine fits Page model shows good linearity. Conclusions： The critical temperature and the optimal drying temperature where HLD and SHD can affect the weight loss rate in the process of calamine were explored using the theories and methods of both biophysical chemistry and processing of Chinese materia medica. This work provides a good example for the study of the process of other Chinese medicines using modern analytical techniques.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.11873062,11427901,11673038,11803002,11973056,11973061,12003051 and 12073040)supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant Nos.XDA15320102 and XDA15052200)。
文摘The Fourier transform spectrometer(FTS)is a core instrument for solar observation with high spectral resolution,especially in the infrared.The Infrared System for the Accurate Measurement of Solar Magnetic Field(AIMS),working at 10-13μm,will use an FTS to observe the solar spectrum.The Bruker IFS-125 HR,which meets the spectral resolution requirement of AIMS but simply equips with a point source detector,is employed to carry out preliminary experiment for AIMS.A sun-light feeding experimental system is further developed.Several experiments are taken with them during 2018 and 2019 to observe the solar spectrum in the visible and near infrared wavelength,respectively.We also proposed an inversion method to retrieve the solar spectrum from the observed interferogram and compared it with the standard solar spectrum atlas.Although there is a wavelength limitation due to the present sun-light feeding system,the results in the wavelength band from 0.45-1.0μm and 1.0-2.2μm show a good consistency with the solar spectrum atlas,indicating the validity of our observing configuration,the data analysis method and the potential to work in longer wavelength.The work provided valuable experience for the AIMS not only for the operation of an FTS but also for the development of its scientific data processing software.
基金National Natural Science Fundation of China(60578036)
文摘The miniaturization of spectrometer opens a new application area with real-time and on-site measurements.The Fourier transform spectrometer(FTS)is much attractive considering its particular advantages among the approaches.This paper reviews the current status of micro FTS in worldwide and describes its developments;In addition,analyzed are the key problems in designing and fabricating FTS to be settled during the miniaturization.Finally,a novel model of micro FTS with no moving parts is proposed and analyzed,which may provide new concepts for the design of spectrometers.
基金supported by the National Natural Science Foundation China(No.42022051,No.U21A2028)Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.Y202089)the HFIPS Director's Fund(No.YZJJ202101,No.BJPY2023A02).
文摘Optical frequency combbased Fourier transform spectroscopy has the features of broad spectral bandwidth,high sensitivity,andmultiplexed trace gas detection,which has valuable application potential in the fields of precision spectroscopy and trace gas detection.Here,we report the development of a mid-infrared Fourier transform spectrometer based on an optical frequency comb combined with a Herriott-type multipass cell.Using this instrument,the broadband absorption spectra of several important molecules,including methane,acetylene,water molecules and nitrous oxide,are measured by near real-time data acquisition in the 2800-3500 cm^(-1)spectral region.The achieved minimum detectable absorption of the instrument is 4.4×10^(-8)cm^(-1)·Hz^(-1/2)per spectral element.Broadband spectra of H_(2)0 are fited using the Voigt profile multispectral fitting technique and the consistency of the concentration inversion is 1%.Our system also enables precise spectroscopic measurements,and it allows the determination of the spectral line positions and upper state constants of N_(2)O in the(0002)-(1000)band,with results in good agreement with those reported by Toth[Appl.Opt.30,5289(1991)].
基金Supported by State Key Development Program for Basic Research of China(2007CB210208)National Science and Technology Major Project of China(2008ZX07101)China Scholarship Council(CSC),Natural Science and Engineering Research Council of Canada(NSERC),BIOCAP,and Canadian Funding for Innovations(CFI)
文摘Bio-oil is a new liquid fuel produced by fast pyrolysis,which is a promising technology to convert bio-mass into liquid. Pyrolytic lignin extracted from bio-oil,a fine powder,contributes to the instability of bio-oil. The paper presents the structural features of three kinds of pyrolytic lignin extracted from bio-oil with different methods(WIF,HMM,and LMM) . The pyrolytic lignin samples are characterized by Fourier transform infrared spectrometer(FTIR) and X-ray photoelectron spectroscopy(XPS) . FTIR data indicate that the three pyrolytic lignin samples have similar functional groups,while the absorption intensity is different,and show characteristic vibra-tions of typical lignocellulosic material groups O H(3340-3380 cm-1) ,C H(2912-2929 cm-1) and C O(1652-1725 cm-1) . Comparison in the region(3340-3380 cm-1) indicates that WIF has more O H stretch groups than HMM and LMM. The carbon spectra are fitted to four peaks:C1,C C or C H,BE 283.5 eV;C2,C OR or C OH,BE 284.5-285.8 eV;C3,C O or HO C OR,BE 286.10-287.10 eV;C4,O C O,BE 287.5-287.7 eV. The absence of C1,C C or C H indicates the dominant polymerization structure of aro-matic carbon in pyrolytic lignin samples. For HMM and WIF,C2a and C2b can not be separated,so there is no free hydroxyl group in the samples. The oxygen peaks are also fitted to four peaks:O1,OH,BE = 530.3 eV;O2,RC O,BE 531.45-531.72 eV;O3,O C O,BE = 532.73-533.74 eV;O4,H2O,BE 535 eV. The absence of O1 and O4 indicates that little hydroxyl groups and adsorbed water are present in the samples.
基金The National Natural Science Foundation of China (No. 20477043), the Knowledge Innovation Foundation of Chinese Academy ofSciences (No. KJCX2-SW-H08) and the National Synchrotron Graduation Innovation Foundation of Ministry of Education of China (Hefei)
文摘Photooxidation reaction of toluene in smog chamber systems was initiated by the UV radiation of tolucne/CH5ONO/NOx mixtures. The products of the photooxidation reaction of toluene and its subsequent reactions were analyzed directly utilizing Fourier transform infrared spectrometer （FTIR）. Detailed assignments to FTIR spectrum of gas-phase products were given. The information of some important functional groups in the products, such as, carbonyl groups （C-O）, hydroxyl groups （-OH）, carboxylic acid （- COOH）, C-C bonding, N O bonding and C-H bonding （C H）, was got from this analysis. These results were compared to those analyzed by aerosol time of flight mass spectrometer （ATOFMS）. It was found that there are some differcnccs between FTIR analysis of gas-phase products and that of particle-phase, for example, the products with carbonyl groups, which were connected to unsaturated chemical bonds, was relatively higher in the gas phase, while kctoncs, aldehydes, carboxylic acid and organonitrates were the dominant functional groups in the aerosol-phase reaction products. The possible reaction pathways of some important products in the gas phase were also discussed.
基金supported by the National Natural Science Foundation of China(Grant Nos.12020101002,and 11925304)Chinese Academy of Sciences(CAS)(Grant No.GJJSTD20210002)+1 种基金National Key R&D Program of China(Grant No.2017YFA0304003)CAS Key Lab for Radio Astronomy。
文摘Cosmic-microwave-background(CMB)B-mode measurements may reveal primordial gravitational waves from the earliest phases of the Big Bang.As the first CMB experiment in the northern hemisphere,the Ali CMB polarization telescope(Ali CPT)will carry out measurements of this kind at Ali(Nagri)in Tibet.It is therefore of particular importance to understand the terahertz atmospheric transmission at this site.Here we report on the measurement results for three consecutive seasons with a Fourier transform spectrometer(FTS)spanning a wide frequency range from 0.75 to 14 THz.The zenith median precipitable-watervapor(PWV)is found to be as low as 1 mm at the Ali CPT site,which appears as good as those CMB B-mode measurement sites in the southern hemisphere such as Chile's Atacama Desert.
基金Supported by the TanSat Project(2011AA12A104)under a contract with the National Science and Technology Support Program of China
文摘In order to correctly use the column-averaged atmospheric COdry-air mole fraction(XCO) data in the COflux studies, XCOmeasurements retrieved from the Orbiting Carbon Observatory-2(OCO-2) in 2015 were compared with those obtained from the global ground-based high-resolution Fourier Transform Spectrometer(FTS) participating in the Total Carbon Column Observing Network(TCCON). The XCOretrieved from three observing modes adopted by OCO-2, i.e., nadir, target, and glint, were separately validated by the FTS measurements at up to eight TCCON stations located in different areas. These comparisons show that OCO-2 glint mode yields the best qualitative estimations of COconcentration among the three operational approaches. The overall results regarding the glint mode show no obvious systematic biases. These facts may indicate that the glint concept is appropriate for not only oceans but also land regions. Negative systematic biases in nadir and target modes have been found at most TCCON sites. The standard deviations of XCOretrieved from target and nadir modes within the observation period are similar, and larger than those from glint mode. We also used the FTS site in Beijing, China, to assess the OCO-2 XCOin 2016. This site is located in a typical urban area, which has been absent in previous studies. Overall, OCO-2 XCOagrees well with that from FTS at this site. Such a study will benefit the validation of the newly launched TanSat products in China.
基金financially supported by the National Natural Science Foundation of China(No.41906039)the Key Research and Development Program of Shandong Province(No.2019JZZY010333)the Shandong University Future Plan for Young Scholars and Fundamental Research Funds of Shandong University。
文摘A zwitterionic nanofiber film was constructed through combining zwitterionic polymer with anodic aluminum oxide template for anti-adhering typical marine corrosive microorganisms,i.e.Pseudomonas aeruginosa,Desulfovibrio vulgaris and Chaetoceros muelleri.Results showed that the fabricated zwitterionic polymers film has fibrous nanostructure with uniform distribution and super hydrophilia.This film has wide anti-adhering properties,and it can effectively reduce the attachment of these three microorganisms by more than 99%.Moreover,the adhesion of extracellular polymeric substances secreted from these three microorganisms are also inhibited,which is one reason for the fabricated nanofiber film with antiadhesion characteristic of microorganisms.This research provides valuable information for solving the problem of microbial adhesion on metal surfaces in the marine environment.
基金Supported by the the Key Technology Research for TCM Modernization of Shanxi Province"Zhendong"Special Project(No.2014ZD0302)
文摘Objective： To determine the pyrolysis characteristics of calcined and processed calamine, qualitatively and quantitatively compare the contents of related elements, morphology and functional groups of the pyrolysis products dried at different heating temperatures and explore the critical temperature and the optimal drying temperature for the process of calamine with Huanglian Decoction（HLD, 黄连汤） and San Huang Decoction（SHD, 三黄汤）. Methods： Pyrolysis products were prepared by programmable and constantly heating the calcined and processed calamine to or at different heating temperatures. Thermogravimetry（TG） was used to test their pyrolysis characteristics. Fourier transform infrared spectroscopy and scanning electron microscopeenergy dispersive spectrometer were used to determine their morphology, functional groups and element contents. Page model was used to investigate the constant drying kinetics of processed calamine. Results： The adding of HLD or SHD to calcined calamine（CC） can slow its weight loss in drying pyrolysis process. The temperature ranges where HLD and SHD can affect its weight loss were 65–150 ℃ and 74–180 ℃, respectively. The drying temperature was optimized as 90 ℃. The drying kinetic for the processed calamine fits Page model shows good linearity. Conclusions： The critical temperature and the optimal drying temperature where HLD and SHD can affect the weight loss rate in the process of calamine were explored using the theories and methods of both biophysical chemistry and processing of Chinese materia medica. This work provides a good example for the study of the process of other Chinese medicines using modern analytical techniques.
