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An inversely designed integrated spectrometer with reconfigurable performance and ultra-low power consumption
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作者 Ang Li Yifan Wu +3 位作者 Chang Wang Feixia Bao Zongyin Yang Shilong Pan 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第8期43-54,共12页
Despite the pressing demand for integrated spectrometers,a solution that deliver high-performance while being practically operated is still missing.Furthermore,current integrated spectrometers lack reconfigurability i... Despite the pressing demand for integrated spectrometers,a solution that deliver high-performance while being practically operated is still missing.Furthermore,current integrated spectrometers lack reconfigurability in their performance,which is highly desirable for dynamic working scenarios.This study presents a viable solution by demonstrating a userfriendly,reconfigurable spectrometer on silicon.At the core of this innovative spectrometer is a programmable photonic circuit capable of exhibiting diverse spectral responses,which can be significantly adjusted using on-chip phase shifters.The distinguishing feature of our spectrometer lies in its inverse design approach,facilitating effortless control and efficient manipulation of the programmable circuit.By eliminating the need for intricate configuration,our design reduces power consumption and mitigates control complexity.Additionally,our reconfigurable spectrometer offers two distinct operating conditions.In the Ultra-High-Performance mode,it is activated by multiple phase-shifters and achieves exceptional spectral resolution in the picometer scale while maintaining broad bandwidth.On the other hand,the Ease-of-Use mode further simplifies the control logic and reduces power consumption by actuating a single-phase shifter.Although this mode provides a slightly degraded spectral resolution of approximately 0.3 nm,it prioritizes ease of use and is wellsuited for applications where ultra-fine spectral reconstruction is not a primary requirement. 展开更多
关键词 silicon photonics integrated spectrometers computational spectrometers
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Optimized online filter stack spectrometer for ultrashort X-ray pulses
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作者 Jia-Xing Wen Ge Ma +17 位作者 Ming-Hai Yu Yu-Chi Wu Yong-Hong Yan Shao-Yi Wang Huai-Zhong Gao Lu-Shan Wang Yu-Gang Zhou Qiang Li Yue Yang Fang Tan Xiao-Hui Zhang Jie Zhang Wen-Bo Mo Jing-Qin Su Wei-Min Zhou Yu-Qiu Gu Ming Zeng Zong-Qing Zhao 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第5期85-98,共14页
Currently,with the advent of high-repetition-rate laser-plasma experiments,the demand for online diagnosis for the X-ray spectrum is increasing because the laser-plasma-generated X-ray spectrum is very important for c... Currently,with the advent of high-repetition-rate laser-plasma experiments,the demand for online diagnosis for the X-ray spectrum is increasing because the laser-plasma-generated X-ray spectrum is very important for characterizing electron dynamics and applications.In this study,scintillators and silicon PIN(P-type–intrinsic-N-type semiconductor)diodes were used to construct a wideband online filter stack spectrometer.The X-ray sensor and filter arrangement was optimized using a genetic algorithm to minimize the condition number of the response matrix.Consequently,the unfolding error was significantly reduced based on numerical experiments.The detector responses were quantitatively calibrated by irradiating the scintillator and PIN diode with various nuclides and comparing the measuredγ-ray peaks.A prototype 15-channel spectrometer was developed by integrating an X-ray detector with front-and back-end electronics.The prototype spectrometer could record X-ray pulse signals at a repetition rate of 1 kHz.Furthermore,an optimized spectrometer was employed to record the real-time spectra of laser-driven bremsstrahlung sources.This optimized spectrometer offers a compact solution for spectrum diagnostics of ultrashort X-ray pulses,exhibiting improved accuracy in terms of spectrum measurements and repetition rates,and could be widely used in next-generation high-repetition-rate high-power laser facilities. 展开更多
关键词 Filter stack spectrometer Laser plasma diagnostics X-ray diagnostics Scintillator PIN diode
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Design and implementation of the monochromator shielding for the cold neutron spectrometers XINGZHI and BOYA
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作者 汪晋辰 刘娟娟 +6 位作者 徐大业 Florian Grünauer 郝丽杰 刘蕴韬 张红霞 程鹏 鲍威 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期96-102,共7页
An innovative monochromator shielding is designed and implemented for the cold neutron spectrometers XINGZHI and BOYA operated by Renmin University of China at China Advanced Research Reactor.Via Monte Carlo simulatio... An innovative monochromator shielding is designed and implemented for the cold neutron spectrometers XINGZHI and BOYA operated by Renmin University of China at China Advanced Research Reactor.Via Monte Carlo simulations and careful mechanical designs,a shielding configuration has been successfully developed to satisfy safety requirements of below 3μSv/h dose rate at its exterior,meanwhile fulfilling space,floor load and nonmagnetic requirements.Composite materials are utilized to form the sandwich-type shielding walls:the inner layer of boron carbide rubber,the middle layer of steel-encased lead and the outer layer of borated polyethylene.Special-shaped liftable shielding blocks are incorporated to facilitate a continuous adjustment of the neutron energy while preventing radiation leakage.Our work has demonstrated that by utilizing composite shielding materials,along with the sandwich structure and liftable shielding blocks,a compact and lightweight shielding solution can be achieved.This enables the realization of advanced neutron scattering instruments that provide expanded space of measurement,larger energy and momentum coverage,and higher flux on the sample.This shielding represents the first of its kind in neutron scattering instruments in China.Following its successful operation,it has been subsequently employed by other neutron instruments across the country. 展开更多
关键词 neutron scattering cold neutron spectrometer monochromator shielding sandwich shielding structure
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A seven-crystal spectrometer for high-energy resolution X-ray spectroscopy at Shanghai Synchrotron Radiation Facility
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作者 Bing-Bao Mei Liang-Xin Wang +6 位作者 Song-Qi Gu Xiao-Zhi Su Shuo Zhang Yao Wei Jing-Yuan Ma Zheng Jiang Fei Song 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第9期82-91,共10页
A Johann-type X-ray spectrometer was successfully developed at the hard X-ray branch(in-vacuum undulator with a 24-mm periodic length)of the energy material beamline(E-line)at the Shanghai Synchrotron Radiation Facili... A Johann-type X-ray spectrometer was successfully developed at the hard X-ray branch(in-vacuum undulator with a 24-mm periodic length)of the energy material beamline(E-line)at the Shanghai Synchrotron Radiation Facility(SSRF).This spectrometer was utilized to implement X-ray emission spectroscopy(XES),high-energy resolution fluorescence-detected X-ray absorption spectroscopy(HERFD-XAS),and resonant inelastic X-ray scattering.Seven spherically bent crystals were positioned on the respective vertical 500-mm-diameter Rowland circles,adopting an area detector to increase the solid angle to 1.75%of 4πsr,facilitating the study of low-concentrate systems under complex reaction conditions.Operated under the atmosphere pressure,the spectrometer covers the energy region from 3.5 to 18 keV,with the Bragg angle ranging from 73°to 86°during vertical scanning.It offers a promised energy resolution of sub-eV(XES)and super-eV(HERFD-XAS).Generally,these comprehensive core-level spectroscopy methods based on hard X-rays at the E-line with an extremely high photon flux can meet the crucial requirements of a green energy strategy.Moreover,they provide substantial support for scientific advances in fundamental research. 展开更多
关键词 X-ray emission spectroscopy High-energy-resolution X-ray spectrometer Johann geometry Energy materials SSRF
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Mid-infrared Optical Frequency Comb-based Fourier Transform Spectrometer for Broadband Molecular Spectroscopy
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作者 Feihu Cheng Weixiong Zhao +5 位作者 Bo Fang Nana Yang Shuangshuang Li Weijun Zhang Lunhua Deng Weidong Chen 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第4期471-480,I0093,共11页
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
关键词 Mid-infrared optical frequency comb Multi-pass cell Fourier transform infrared spectrometer
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Artificial neural network-based method for discriminating Compton scattering events in high-purity germaniumγ-ray spectrometer
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作者 Chun-Di Fan Guo-Qiang Zeng +5 位作者 Hao-Wen Deng Lei Yan Jian Yang Chuan-Hao Hu Song Qing Yang Hou 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期64-84,共21页
To detect radioactive substances with low activity levels,an anticoincidence detector and a high-purity germanium(HPGe)detector are typically used simultaneously to suppress Compton scattering background,thereby resul... To detect radioactive substances with low activity levels,an anticoincidence detector and a high-purity germanium(HPGe)detector are typically used simultaneously to suppress Compton scattering background,thereby resulting in an extremely low detection limit and improving the measurement accuracy.However,the complex and expensive hardware required does not facilitate the application or promotion of this method.Thus,a method is proposed in this study to discriminate the digital waveform of pulse signals output using an HPGe detector,whereby Compton scattering background is suppressed and a low minimum detectable activity(MDA)is achieved without using an expensive and complex anticoincidence detector and device.The electric-field-strength and energy-deposition distributions of the detector are simulated to determine the relationship between pulse shape and energy-deposition location,as well as the characteristics of energy-deposition distributions for fulland partial-energy deposition events.This relationship is used to develop a pulse-shape-discrimination algorithm based on an artificial neural network for pulse-feature identification.To accurately determine the relationship between the deposited energy of gamma(γ)rays in the detector and the deposition location,we extract four shape parameters from the pulse signals output by the detector.Machine learning is used to input the four shape parameters into the detector.Subsequently,the pulse signals are identified and classified to discriminate between partial-and full-energy deposition events.Some partial-energy deposition events are removed to suppress Compton scattering.The proposed method effectively decreases the MDA of an HPGeγ-energy dispersive spectrometer.Test results show that the Compton suppression factors for energy spectra obtained from measurements on ^(152)Eu,^(137)Cs,and ^(60)Co radioactive sources are 1.13(344 keV),1.11(662 keV),and 1.08(1332 keV),respectively,and that the corresponding MDAs are 1.4%,5.3%,and 21.6%lower,respectively. 展开更多
关键词 High-purity germaniumγ-ray spectrometer Pulse-shape discrimination Compton scattering Artificial neural network Minimum detectable activity
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An empirical method for joint inversion of wave and wind parameters based on SAR and wave spectrometer data
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作者 Yong Wan Xiaona Zhang +2 位作者 Shuyan Lang Ennan Ma Yongshou Dai 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第5期133-144,共12页
Synthetic aperture radar(SAR)and wave spectrometers,crucial in microwave remote sensing,play an essential role in monitoring sea surface wind and wave conditions.However,they face inherent limitations in observing sea... Synthetic aperture radar(SAR)and wave spectrometers,crucial in microwave remote sensing,play an essential role in monitoring sea surface wind and wave conditions.However,they face inherent limitations in observing sea surface phenomena.SAR systems,for instance,are hindered by an azimuth cut-off phenomenon in sea surface wind field observation.Wave spectrometers,while unaffected by the azimuth cutoff phenomenon,struggle with low azimuth resolution,impacting the capture of detailed wave and wind field data.This study utilizes SAR and surface wave investigation and monitoring(SWIM)data to initially extract key feature parameters,which are then prioritized using the extreme gradient boosting(XGBoost)algorithm.The research further addresses feature collinearity through a combined analysis of feature importance and correlation,leading to the development of an inversion model for wave and wind parameters based on XGBoost.A comparative analysis of this model with ERA5 reanalysis and buoy data for of significant wave height,mean wave period,wind direction,and wind speed reveals root mean square errors of 0.212 m,0.525 s,27.446°,and 1.092 m/s,compared to 0.314 m,0.888 s,27.698°,and 1.315 m/s from buoy data,respectively.These results demonstrate the model’s effective retrieval of wave and wind parameters.Finally,the model,incorporating altimeter and scatterometer data,is evaluated against SAR/SWIM single and dual payload inversion methods across different wind speeds.This comparison highlights the model’s superior inversion accuracy over other methods. 展开更多
关键词 synthetic aperture radar(SAR) wave spectrometer extreme gradient boosting(XGBoost) joint inversion method wave and wind parameters
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Separation and characterization of petroleum asphaltene fractions by ESI FT-ICR MS and UV-vis spectrometer 被引量:6
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作者 WANG ShanShan YANG Chuang +2 位作者 XU ChunMing ZHAO SuoQi SHI Quan 《Science China Chemistry》 SCIE EI CAS 2013年第7期856-862,共7页
Using heptane, toluene, and tetrahydrofuran (THF) as eluant, asphaltenes were fractionated into five fractions based on their polarity and solubility. The molecular composition of polar heteroatom species in both as... Using heptane, toluene, and tetrahydrofuran (THF) as eluant, asphaltenes were fractionated into five fractions based on their polarity and solubility. The molecular composition of polar heteroatom species in both asphaltene and its fractions were ana- lyzed by negative-ion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS). The application of UV-vis spectrometer in characterizing asphaltene composition and measuring asphaltene concentration was discussed. About 11.9 wt% asphaltene components adsorbed permanently on silica gel in the extrography column after exces- sive elution with various solvents. In negative FT-ICR MS, the mass spectra show that acidic and neutral nitrogen-containing compounds such as N1 and NIS1 mainly existe in the first three less polar fractions, while oxygen-containing compounds such as 02, O2S, O2S2, 03, and 04 show high relative abundance in more polar fractions. These results suggest oxygen-containing compounds have stronger adsorption ability with silica gel. It was observed that the double bond equivalence (DBE) distribu- tion of N1 class species in the fractions shifted to higher values while the carbon number shifted to smaller numbers as polarity of fractions increased. This indicates that acidic and neutral Nl compounds with longer carbon chain and less aromaticity have less polarity compared with those with shorter carbon chain and stronger aromaticity. UV-vis absorbance indicats that fractions containing the most aromatic and most polar asphaltene have better absorbance at long wavelength, while the fractions that consist of least aromatic and least polar asphatlenes show high absorbance at short wavelength. 展开更多
关键词 ASPHALTENE FT-ICR MS uv-vis heavy oil
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Accuracy analysis of iron content of galvanized coating using an X-ray fluorescence spectrometer with an L-spectrum
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作者 WANG Jingjing CHEN Yanfei 《Baosteel Technical Research》 CAS 2023年第4期35-40,共6页
The accuracy(repeatability and reproducibility) of the iron content analysis of galvanized coating using an X-ray fluorescence spectrometer with an L-spectrum is not better than that of flame atomic absorption spectro... The accuracy(repeatability and reproducibility) of the iron content analysis of galvanized coating using an X-ray fluorescence spectrometer with an L-spectrum is not better than that of flame atomic absorption spectrometry, sometimes it exceeds the quality control limit.Influences, such as current, voltage, equipment(internal circulating water, 10%CH4+90%Ar, and vacuum) checking, instrument monitoring, sample cleaning, and oper-ators, were investigated by means of 6-sigma and lean operations to improve accuracy. 展开更多
关键词 X-ray fluorescence spectrometer Lspectrum galvanized coating iron content
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Design and calibration of an elliptical crystal spectrometer for the diagnosis of proton-induced x-ray emission(PIXE)
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作者 方言律 李东彧 +9 位作者 程浩 高原 申泽清 杨童 李昱泽 夏亚东 晏炀 颜莎 林晨 颜学庆 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期220-225,共6页
Laser-driven proton-induced x-ray emission(laser-PIXE) is a nuclear analysis method based on the compact laser ion accelerator. Due to the transient process of ion acceleration, the laser-PIXE signals are usually spur... Laser-driven proton-induced x-ray emission(laser-PIXE) is a nuclear analysis method based on the compact laser ion accelerator. Due to the transient process of ion acceleration, the laser-PIXE signals are usually spurted within nanoseconds and accompanied by strong electromagnetic pulses(EMP), so traditional multi-channel detectors are no longer applicable.In this work, we designed a reflective elliptical crystal spectrometer for the diagnosis of laser-PIXE. The device can detect the energy range of 1 keV–11 ke V with a high resolution. A calibration experiment was completed on the electrostatic accelerator of Peking University using samples of Al, Ti, Cu, and ceramic artifacts. The detection efficiency of the elliptical crystal spectrometer was obtained in the order of 10-9. 展开更多
关键词 elliptical crystal spectrometer proton-induced x-ray emission applications of laser ion accelera-tion
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Evaluation of Uncertainty in Determination of Ethyl Maltol in Vegetable Oil by Ultra-high Performance Liquid Chromatograph-Mass Spectrometer(UPLC-MS)
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作者 Lei ZHANG 《Agricultural Biotechnology》 CAS 2023年第3期113-115,共3页
[Objectives]This study was conducted to establish an uncertainty evaluation method for the determination of ethyl maltol by ultra-high performance liquid chromatograph-mass spectrometer(UPLC-MS).[Methods]A mathematica... [Objectives]This study was conducted to establish an uncertainty evaluation method for the determination of ethyl maltol by ultra-high performance liquid chromatograph-mass spectrometer(UPLC-MS).[Methods]A mathematical model of uncertainty was established by analyzing the method for determining ethyl maltol using UPLC-MS.The sources of uncertainty were analyzed,and the components of uncertainty were calculated to evaluate the expanded uncertainty of the method.[Results]When the content of ethyl maltol in edible vegetable oil was 1657μg/kg,the expanded uncertainty was 22.4μg/kg(K=2,P=95%).[Conclusions]The uncertainty in this evaluation model mainly came from standard solution preparation,sample weighing,dilution of sample to constant volume,standard curve fitting,and repeated measurement. 展开更多
关键词 Ultra-high performance liquid chromatograph-mass spectrometer DETERMINATION Ethyl maltol Uncertainty
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羽流UV-VIS辐射在液体火箭发动机故障诊断中的应用技术研究 被引量:12
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作者 赵永学 张育林 +1 位作者 李麦亮 周进 《宇航学报》 EI CAS CSCD 北大核心 2002年第1期34-39,共6页
为发展基于羽流 UV - VIS辐射光谱的液体火箭发动机故障诊断技术 ,以光谱采集系统为测量手段 ,对三组元模型发动机排气羽流及用以模拟煤油 -氧发动机燃烧的气氧 -煤油火焰的近紫外与可见光谱辐射进行了实验研究 ,利用辐射传递模型对实... 为发展基于羽流 UV - VIS辐射光谱的液体火箭发动机故障诊断技术 ,以光谱采集系统为测量手段 ,对三组元模型发动机排气羽流及用以模拟煤油 -氧发动机燃烧的气氧 -煤油火焰的近紫外与可见光谱辐射进行了实验研究 ,利用辐射传递模型对实验结果进行了理论计算 ,利用演化算法对实验结果进行了反算。 展开更多
关键词 液体火箭发动机 故障诊断 羽流 辐射光谱检测 uv-vis
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樟脑磺酸掺杂聚苯胺在不同有机溶剂中的UV-Vis光谱 被引量:5
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作者 於黄中 黄河 +2 位作者 熊予莹 刘少琼 任兵 《光谱实验室》 CAS CSCD 2002年第3期290-292,共3页
由于不同的有机溶剂与樟脑磺酸掺杂的聚苯胺 (PANI.HCSA)有不同的作用 ,故 PANI.HCSA在不同的有机溶剂中有不同的紫外 -可见光谱。本文研究了 PANI.HCSA在有机溶剂间甲酚 (m- cresol)、二甲基亚砜 (DMSO)、N,N-二甲酰胺 (DMF)、N-甲基 -... 由于不同的有机溶剂与樟脑磺酸掺杂的聚苯胺 (PANI.HCSA)有不同的作用 ,故 PANI.HCSA在不同的有机溶剂中有不同的紫外 -可见光谱。本文研究了 PANI.HCSA在有机溶剂间甲酚 (m- cresol)、二甲基亚砜 (DMSO)、N,N-二甲酰胺 (DMF)、N-甲基 - 2 -吡咯烷酮 (NMP)中的 UV- Vis光谱的不同及其变化 。 展开更多
关键词 樟脑磺酸 掺杂 聚苯胺 有机溶剂 uv-vis光谱 导电聚合物
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四氮杂芳氧基取代酞菁金属配合物的UV-Vis吸收光谱研究 被引量:3
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作者 薛金萍 洪湖铭 +4 位作者 叶廷秀 范长安 孙纲春 陈耐生 黄金陵 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2006年第11期2050-2052,共3页
测定了6个系列18种四氮杂芳氧基取代酞菁金属配合物(R4PCM,R=4-吡啶氧基、8-喹啉氧基、2-甲基-8喹啉氧基;取代位置分别为:α位及β位;M=Ni(Ⅱ),Cu(Ⅱ),Zn(Ⅱ))的UV-Vis吸收光谱。探讨了中心金属、取代基种类及取代位置、... 测定了6个系列18种四氮杂芳氧基取代酞菁金属配合物(R4PCM,R=4-吡啶氧基、8-喹啉氧基、2-甲基-8喹啉氧基;取代位置分别为:α位及β位;M=Ni(Ⅱ),Cu(Ⅱ),Zn(Ⅱ))的UV-Vis吸收光谱。探讨了中心金属、取代基种类及取代位置、溶剂对酞菁金属配合物UV-Vis吸收光谱中Q带最大吸收波长(λmax)的影响,实验结果表明:标题配合物的Q带λmax在680nm左右;与相同中心金属无取代酞菁金属配合物(669~671nm)比较,标题配合物的Q带λmax都发生了不同程度的红移;当取代基在α位时其种类对标题配合物Q带λmax的影响较在β位时显著,且相同取代基及中心金属的α位取代配合物的Q带λmax较β位取代配合物的红移更为明显;中心金属、溶剂对标题配合物的Q带λmax影响不明显。 展开更多
关键词 氮杂芳氧基 取代酞菁金属配合物 uv-vis吸收光谱
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HPLC法和UV-VIS法测定灵芝孢子粉中灵芝三萜及灵芝多糖的含量 被引量:14
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作者 王筱婧 林焕冰 +1 位作者 徐江 叶亚林 《当代医学》 2009年第31期128-130,共3页
目的建立测定灵芝孢子粉中的两个有效成分灵芝三萜及灵芝多糖含量的方法,为进一步开发和应用灵芝孢子粉提供依据。方法以灵芝酸C2为标准品,通过HPLC法对灵芝孢子粉中灵芝酸C2的含量进行测定。色谱条件为:检测波长254nm;流动相为甲醇:水... 目的建立测定灵芝孢子粉中的两个有效成分灵芝三萜及灵芝多糖含量的方法,为进一步开发和应用灵芝孢子粉提供依据。方法以灵芝酸C2为标准品,通过HPLC法对灵芝孢子粉中灵芝酸C2的含量进行测定。色谱条件为:检测波长254nm;流动相为甲醇:水=55∶45,各加1%冰醋酸;柱温40℃;流速0.7mL/min。以葡萄糖为标准品,采用硫酸-蒽酮比色法,通过UV-VIS法对灵芝孢子粉中灵芝多糖的含量进行测定。结果HPLC法测得三批灵芝孢子粉中灵芝酸C2含量约为0.129‰,0.108‰和0.094‰,灵芝酸C2在7.35~147μg/mL范围内,浓度与峰面积呈良好的线性关系,r=0.9999,回收率为95.9%,95.6%和96.4%。UV-VIS法测得三批灵芝孢子粉中灵芝多糖的含量约为1.152%,1.129%和1.007%,葡萄糖在14.9~119.1μg/mL的范围内,浓度和吸光度呈线性关系,r=0.9991,回收率为95.0%,95.1%和95.2%。结论方法简便、准确,可用于灵芝孢子粉中灵芝三萜和灵芝多糖的含量测定。 展开更多
关键词 灵芝孢子粉 灵芝三萜 灵芝酸C2 灵芝多糖 HPLC uv-vis
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Separation of Ions from Volatile Organic Compounds Using High-Field Asymmetric Waveform Ion Mobility Spectrometry-Mass Spectrometer 被引量:2
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作者 李华 王晓浩 +2 位作者 唐飞 杨吉 丁力 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第2期125-132,I0001,共9页
A combination of high-field asymmetric waveform ion mobility spectrometry (FAIMS) with mass spectrometer (MS) was analyzed. FAIMS separates ions from the volatile organic compounds in the gas-phase as an ion-filte... A combination of high-field asymmetric waveform ion mobility spectrometry (FAIMS) with mass spectrometer (MS) was analyzed. FAIMS separates ions from the volatile organic compounds in the gas-phase as an ion-filter for MS. The sample ions were created at ambient pressure by ion source, which was equipped with a 10.6 eV UV discharge lamp (A=116.5 nm). The drift tube of FAIMS is composed of two parallel planar electrodes and the dimension is 10 mm×8 mm×0.5 mm. FAIMS was investigated when driven by the high-filed rectangular asymmetric waveform with the peak-to-peak voltage of 1.36 kV at the frequency of 1 MHz and the duty cycle of 30%. The acetone, the butanone, and their mixture were adopted to characterize the FAIMS-MS. The mass spectra obtained from MS illustrate that there are ion-molecular reactions between the ions and the sample neutral molecular. And the proton transfer behavior in the mixture of the acetone and the butanone is also observed. With the compensation voltage tuned from -30 V to 10 V with a step size of 0.1 V, the ion pre-separation before MS is realized. 展开更多
关键词 High-field asymmetric waveform ion mobility spectrometry Mass spectrometer Ion-filter Ion-molecular reaction Proton transfer
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ATR-FTIR和UV-Vis结合数据融合策略鉴别滇黄精产地 被引量:8
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作者 张娇 王元忠 +1 位作者 杨维泽 张金渝 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2021年第5期1410-1416,共7页
黄精药材品质优劣与基原植物产地环境因子密切相关,建立简单、快速且能够准确鉴别药材产地的方法对保证其质量可控及用药安全具有重要的理论意义和应用前景。研究中以云南、四川和广西9个产地的133份滇黄精Polygonatum kingianum coll.e... 黄精药材品质优劣与基原植物产地环境因子密切相关,建立简单、快速且能够准确鉴别药材产地的方法对保证其质量可控及用药安全具有重要的理论意义和应用前景。研究中以云南、四川和广西9个产地的133份滇黄精Polygonatum kingianum coll.et Hemsl根茎为试验材料,采集衰减全反射-傅里叶变换红外光谱(ATR-FTIR)和紫外-可见光光谱(UV-Vis)数据预处理后分别建立单一光谱随机森林(Random forest,RF)模型;将ATR-FTIR与UV-Vis数据直接串联完成低级融合,提取两种光谱的主成分数(PCs)和潜在变量(LVs)以实现中级(中级融合PCs和中级融合LVs)和高级数据融合(高级融合PCs和高级融合LVs),基于不同数据融合策略分别建立RF模型;比较不同模型的正确率(ACC)、灵敏度(SEN)和特异性(SPE),筛选产地鉴别最佳模型。结果显示,不同产地滇黄精ATR-FTIR和UV-Vis峰型相似,吸光度略有差异,ATR-FTIR显示14个共有峰,与糖类、甾体皂苷、黄酮类和生物碱类物质有关,其UV-Vis共有峰主要位于272及327 nm处,与黄酮类物质有关;ATR-FTIR、UV-Vis和低级融合的RF模型,训练集和预测集ACC分别为(76.34%,95.00%),(80.65%,95.00%)和(83.87%,100.00%),但SEN和SPE值较低,故不宜采用;中级融合PCs和中级融合LVs的RF模型的SEN和SPE分别为大于0.91和0.98,训练集ACC分别为91.40%和97.85%,预测集ACC均为97.50%;高级融合PCs和高级融合LVs的RF训练集ACC分别为77.42%和97.85%,预测集ACC均为95.00%,高级融合PCs的RF模型鉴别效果较差,高级融合LVs的RF模型存在过拟合现象;模型鉴别能力为中级融合LVs>中级融合PCs>低级融合>UV-Vis>ATR-FTIR>高级融合PCs;提取LVs对产地鉴别的方法优于PCs;中级融合LVs建立的RF模型鉴别ACC最高,SEN和SPE大于0.98,模型性能最佳。该方法可为黄精药用资源的科学评价提供理论依据和技术支撑。 展开更多
关键词 滇黄精 产地鉴别 数据融合 数据衰减全反射-傅里叶变换红外光谱 紫外-可见吸收光谱(uv-vis)
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稀土纳米金对银染效果的影响及其UV-Vis吸收光谱(英文) 被引量:1
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作者 刘小珍 冯军亮 +3 位作者 刘小舟 陈捷 朱婉婉 桂秀敏 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2015年第12期3560-3564,共5页
制备了La,Ce,Nd,Sm,Eu,Gd,Dy微粒和纳米金,分别用La,Ce,Nd,Sm,Eu,Gd,Dy微粒替代部分的纳米金,研究了La-Au,Ce-Au,Nd-Au,Sm-Au,Eu-Au,Gd-Au,Dy-Au微粒分别对银染效果的影响及其紫外可见(UV-Vis)吸收光谱。与纳米金相比,La-Au,Ce-Au,Nd-... 制备了La,Ce,Nd,Sm,Eu,Gd,Dy微粒和纳米金,分别用La,Ce,Nd,Sm,Eu,Gd,Dy微粒替代部分的纳米金,研究了La-Au,Ce-Au,Nd-Au,Sm-Au,Eu-Au,Gd-Au,Dy-Au微粒分别对银染效果的影响及其紫外可见(UV-Vis)吸收光谱。与纳米金相比,La-Au,Ce-Au,Nd-Au,Sm-Au,Eu-Au,Gd-Au,Dy-Au微粒可延长银染后的斑点持续的时间,其中Nd-Au微粒的效果最好,斑点持续的时间为30min,是纳米金的2.7倍;可大幅度加深斑点的颜色,其中Nd-Au,Sm-Au微粒的效果最好,用Nd微粒替代部分的纳米金,纳米金用量降低了80%,但还能提高银染法的灵敏度。在200~800nm范围,La,Ce,Nd,Sm,Eu,Gd,Dy微粒和纳米金溶液的UV-Vis吸收光谱只有一个吸收峰,λmax分别为275,277,276,276,278,277,278和521nm;La-Au,Ce-Au,Nd-Au,Sm-Au,Eu-Au,Gd-Au,Dy-Au微粒混合液的UV-Vis吸收光谱有两个吸收峰,λmax(RE)和λmax(Au)分别为276和522nm,276和522nm,276和523nm,276和523nm,276和522nm,276和522nm,276和523nm,纳米金和La微粒的吸收峰的波长发生了红移,Ce,Eu,Gd,Dy微粒的吸收峰的波长发生了蓝移,Nd,Sm微粒的吸收峰的波长不变,纳米金与稀土微粒可能有相互作用。 展开更多
关键词 纳米金 稀土 银染 uv-vis吸收光谱
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钛硅沸石 UV-Vis 谱的研究 被引量:8
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作者 李钢 郭新闻 +1 位作者 王祥生 周卓华 《大连理工大学学报》 CAS CSCD 北大核心 1998年第3期359-367,共9页
研究了以TPABr为模板剂合成的TS-1的UV-Vis谱,考察了配料方式、模板剂用量、络合剂、酸处理等对270~280nm峰强度的影响.研究发现:晶化条件对此峰强度影响不大,模板剂用量有一定影响;采用络合剂和酸处理可... 研究了以TPABr为模板剂合成的TS-1的UV-Vis谱,考察了配料方式、模板剂用量、络合剂、酸处理等对270~280nm峰强度的影响.研究发现:晶化条件对此峰强度影响不大,模板剂用量有一定影响;采用络合剂和酸处理可显著降低此峰强度. 展开更多
关键词 沸石 TS-1 uv-vis 分子筛 模板剂
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UV-vis/H_2O_2/草酸铁络合物法光解焦化含酚废水的研究 被引量:11
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作者 张乃东 林秀 +1 位作者 郑威 王宙 《黑龙江大学自然科学学报》 CAS 2002年第1期103-105,共3页
研究了用UV-vis/H2O2/草酸铁络合物法处理含酚废水时诸因素对COD去除效果的影响。通过正交试验确定最佳工艺条件:初始pH=3.7,H2O2、FeSO4、K2C2O4加入量为35mmo1/1、20mmo1/1、... 研究了用UV-vis/H2O2/草酸铁络合物法处理含酚废水时诸因素对COD去除效果的影响。通过正交试验确定最佳工艺条件:初始pH=3.7,H2O2、FeSO4、K2C2O4加入量为35mmo1/1、20mmo1/1、50mmo1/1,反应的持续时间 60min,此条件下再经絮凝处理,废水COD由650mg/1降至32mg/1左右,去除率达95%;挥发酚由15mg/1降至0.5mg/1以下,去除率近97%。本法的处理效果和能耗均好于 UV/Fenton法。 展开更多
关键词 FENTON试剂 过氧化氢 光降解 uv-vis/H2O2/草酸铁络合物 焦化含酚废水 废水处理 光化学氧化
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