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傅立叶红外光谱 1

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Formation of coke in thermal cracking of jet fuel under supercritical conditions

ZHU Yuhong, YU Caixiang, LI Zimu, MI Zhentao, ZHANG Xiangwen

《化学科学与工程前沿（英文）》 2008年 第2卷 第1期   页码 17-21 doi: 10.1007/s11705-008-0024-1

摘要： Continuous-flow reactor experiments were carried out to study coke formation from thermal cracking of home-made jet fuel RP-3 under supercritical conditions. The mechanism and precursor of coke forming were analyzed. The starting cracking temperature of RP-3 fuel was determined to be 471.8°C by differential scanning calorimetry (DSC). Temperature-programmed oxidation and scanning electron microscopy (SEM) characterizations of the stressed tubes showed that there are three different coke species including chemisorbed carbon, amorphous carbon and filamentous coke in the solid deposits. More than 90% of coke deposits are carried away by the supercritical fluid, which has strong capabilities of extraction for coke deposits and their precursors. There were 17.1 wt-% of iron and 11.1 wt-% of chromium found on the coke surface detected by energy dispersive spectroscopy (EDS) which suggests carburetion on alloy. RP-3 fuel and its cracking liquids were analyzed by GC-MS,which showed that the content of alkyl benzene and alkyl naphthalene increased evidently in cracking liquids.

关键词： dispersive spectroscopy     different     extraction     calorimetry     filamentous    

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Factors influencing near infrared spectroscopy analysis of agro-products: a review

Xiao XU, Lijuan XIE, Yibin YING

《农业科学与工程前沿（英文）》 2019年 第6卷 第2期   页码 105-115 doi: 10.15302/J-FASE-2019255

摘要：

The near infrared (NIR) spectroscopy technique has wide applications in agriculture with the advantages of being nondestructive, sensitive, safe and rapid. However, there are still more than 40 error sources influencing the robustness and accuracy of its calibration and operation. Environmental, sample and instrument factors that influence the analysis are discussed in this review, including temperature, humidity and other factors that introduce uncertainty. Error sources from livestock products, fruit and vegetables, which are the most common objects in the field of NIR analysis, are also emphasized in the second part. In addition, studies utilizing different instruments, spectral pretreatments, variable selection methods, wavelength ranges, detection modes and calibration methods are tabulated to illustrate the complications they introduce and how they influence NIR analysis. It is suggested that large scale of data with abundant varieties can be used to build a more robust calibration model, in order to improve the robustness and accuracy of the NIR analytical model, and overcome problems caused by confining analysis to too many uniform samples.

关键词： agro-product     error source     influence factor     near infrared spectroscopy    

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Review: Tip-based vibrational spectroscopy for nanoscale analysis of emerging energy materials

Amun JARZEMBSKI, Cedric SHASKEY, Keunhan PARK

《能源前沿（英文）》 2018年 第12卷 第1期   页码 43-71 doi: 10.1007/s11708-018-0524-8

摘要： Vibrational spectroscopy is one of the key instrumentations that provide non-invasive investigation of structural and chemical composition for both organic and inorganic materials. However, diffraction of light fundamentally limits the spatial resolution of far-field vibrational spectroscopy to roughly half the wavelength. In this article, we thoroughly review the integration of atomic force microscopy (AFM) with vibrational spectroscopy to enable the nanoscale characterization of emerging energy materials, which has not been possible with far-field optical techniques. The discussed methods utilize the AFM tip as a nanoscopic tool to extract spatially resolved electronic or molecular vibrational resonance spectra of a sample illuminated by a visible or infrared (IR) light source. The absorption of light by electrons or individual functional groups within molecules leads to changes in the sample’s thermal response, optical scattering, and atomic force interactions, all of which can be readily probed by an AFM tip. For example, photothermal induced resonance (PTIR) spectroscopy methods measure a sample’s local thermal expansion or temperature rise. Therefore, they use the AFM tip as a thermal detector to directly relate absorbed IR light to the thermal response of a sample. Optical scattering methods based on scanning near-field optical microscopy (SNOM) correlate the spectrum of scattered near-field light with molecular vibrational modes. More recently, photo-induced force microscopy (PiFM) has been developed to measure the change of the optical force gradient due to the light absorption by molecular vibrational resonances using AFM’s superb sensitivity in detecting tip-sample force interactions. Such recent efforts successfully breech the diffraction limit of light to provide nanoscale spatial resolution of vibrational spectroscopy, which will become a critical technique for characterizing novel energy materials.

关键词： vibrational spectroscopy     atomic force microscopy     photo-thermal induced resonance     scanning near-field optical microscopy     tip-enhanced Raman spectroscopy     photo-induced force microscopy     molecular resonances     surface phonon polaritons     energy materials    

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Terahertz time-domain spectroscopy of high-pressure flames

Jason BASSI, Mark STRINGER, Bob MILES, Yang ZHANG

《能源前沿（英文）》 2009年 第3卷 第2期   页码 123-133 doi: 10.1007/s11708-009-0033-x

摘要： Laser spectroscopy in the visible and near infrared is widely used as a diagnostic tool for combustion devices, but this approach is difficult at high pressures within a sooty flame itself. High soot concentrations render flames opaque to visible light, but they remain transparent to far-infrared or terahertz (THz) radiation. The first far-infrared absorption spectra, to the best of our knowledge, of sooty, non-premixed, ethylene high-pressure flames covering the region of 0.2-2.5 THz is presented. A specially designed high-pressure burner which is optically accessible to THz radiation has been built allowing flame transmission measurements up to pressures of 1.6 MPa. Calculations of the theoretical combustion species absorption spectra in the 0.2-3 THz range have shown that almost all the observable features arise from H O. A few OH (1.84 and 2.51 THz), CH (2.58 THz), and NH (1.77 and 2.95 THz) absorption lines are also observable in principle. A large number of H O absorption lines are observed in the ground vibrational in a laminar non-premixed, sooty flame (ethylene) at pressures up to 1.6 MPa.

关键词： terahertz time-domain spectroscopy     high-pressure flames     H2O absorption lines    

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Modeling of oil near-infrared spectroscopy based on similarity and transfer learning algorithm

Yifei Wang, Kai Wang, Zhao Zhou, Wenli Du

《化学科学与工程前沿（英文）》 2019年 第13卷 第3期   页码 599-607 doi: 10.1007/s11705-019-1807-2

摘要： Near-infrared spectroscopy mainly reflects the frequency-doubled and total-frequency absorption information of hydrogen-containing groups (O‒H, C‒H, N‒H, S‒H) in organic molecules for near-infrared lights with different wavelengths, so it is applicable to testing of most raw materials and products in the field of petrochemicals. However, the modeling process needs to collect a large number of laboratory analysis data. There are many oil sources in China, and oil properties change frequently. Modeling of each raw material is not only unfeasible but also will affect its engineering application efficiency. In order to achieve rapid modeling of near-infrared spectroscopy and based on historical data of different crude oils under different detection conditions, this paper discusses about the feasibility of the application of transfer learning algorithm and makes it possible that transfer learning can assist in rapid modeling using certain historical data under similar distributions under a small quantity of new data. In consideration of the requirement of transfer learning for certain similarity of different datasets, a transfer learning method based on local similarity feature selection is proposed. The simulation verification of spectral data of 13 crude oils measured by three different probe detection methods is performed. The effectiveness and application scope of the transfer modeling method under different similarity conditions are analyzed.

关键词： near-infrared spectroscopy     transfer learning     similarity     modeling    

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采用白光X射线源和模拟阵列能量色散阵列探测器的高通量粉末衍射技术 Article

汪晓平, 董伟伟, 张鹏, 唐浩琪, 张澜庭, 杨铁莹, 刘鹏, 汪洪, 项晓东

《工程（英文）》 2022年 第10卷 第3期   页码 81-88 doi: 10.1016/j.eng.2021.05.023

摘要：

在上海同步辐射光源（SSRF）的弯铁光束线上，利用由空间扫描硅漂移探测器（SDD）模拟获得的能量色散阵列探测器，对CeO2样品进行高通量白光X射线粉末衍射（pXRD）实验。考虑到与实验硬件和衍射角相关的多种因素，对数据进行了详细分析和校正。校正后的衍射图谱表明，由能量色散X 射线衍射（EDXRD）获得的不同衍射峰之间的相对强度与来自角度分辨X射线衍射（ARXRD）的相对强度一致，说明EDXRD结果可用于分析未知样品的晶体结构。实验同时采集了X射线荧光（XRF）信号。来自所有像素的XRF计数可直接在能量坐标下叠加，而衍射信号则需在d 空间下叠加，从而大大改善了阵列探测器的峰值强度和信噪比（S/N）。与ARXRD相比，白光X射线衍射信号强度是单色光衍射信号强度的104倍左右。q 空间中衍射峰的半峰全宽（FWHM）取决于探测器的能量分辨率、探测器接收角范围和衍射角大小。如果实验参数选择得当，在当前能量色散探测器的能量分辨率下，EDXRD有可能实现与ARXRD相同甚至更小的半峰全宽。

关键词： 高通量实验     白光X射线衍射     能量色散阵列探测器     能量色散X射线衍射     角分辨X射线衍射    

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Time of flight improved thermally grown oxide thickness measurement with terahertz spectroscopy

《机械工程前沿（英文）》 2022年 第17卷 第4期 doi: 10.1007/s11465-022-0705-3

摘要： As a nondestructive testing technique, terahertz time-domain spectroscopy technology is commonly used to measure the thickness of ceramic coat in thermal barrier coatings (TBCs). However, the invisibility of ceramic/thermally grown oxide (TGO) reflective wave leads to the measurement failure of natural growth TGO whose thickness is below 10 μm in TBCs. To detect and monitor TGO in the emergence stage, a time of flight (TOF) improved TGO thickness measurement method is proposed. A simulative investigation on propagation characteristics of terahertz shows the linear relationship between TGO thickness and phase shift of feature wave. The accurate TOF increment could be acquired from wavelet soft threshold and cross-correlation function with negative effect reduction of environmental noise and system oscillation. Thus, the TGO thickness could be obtained efficiently from the TOF increment of the monitor area with different heating times. The averaged error of 1.61 μm in experimental results demonstrates the highly accurate and robust measurement of the proposed method, making it attractive for condition monitoring and life prediction of TBCs.

关键词： thermal barrier coatings     thermally grown oxide     terahertz spectroscopy     time of flight    

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Cystine-assisted accumulation of gold nanoparticles on ZnO to construct a sensitive surface-enhanced Raman spectroscopy

《化学科学与工程前沿（英文）》 2023年 第17卷 第1期   页码 15-23 doi: 10.1007/s11705-022-2177-8

摘要： Recently, various semiconductor/metal composites have been developed to fabricate surface-enhanced Raman spectroscopy substrates. However, low metal loading on semiconductors is still a challenge. In this study, cystine was introduced to increase the accumulation of gold nanoparticles on zinc oxide, owing to the biomineralization property of cystine. Morphological analysis revealed that the obtained ZnO/Au/cystine composite not only had a higher metal loading but also formed a porous structure, which is beneficial for Raman performance. Compared with ZnO/Au, the ZnO/Au/cystine substrate displayed a 40-fold enhancement in the Raman signal and a lower limit of detection (10–11 mol·L−1) in the detection of rhodamine 6G. Moreover, the substrate has favorable homogeneity and stability. Finally, ZnO/Au/cystine displayed excellent performance toward crystal violet and methylene blue in a test based on river water samples. This study provided a promising method to fabricate sensitive semiconductor/noble metal-based surface-enhanced Raman spectroscopy substrates for Raman detection.

关键词： biomineralization     cystine     semiconductor/metal composite     SERS detection     Raman detection    

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configuration on interface resistances in reverse electrodialysis by in situ electrochemical impedance spectroscopy

《环境科学与工程前沿（英文）》 2022年 第16卷 第4期 doi: 10.1007/s11783-021-1480-9

摘要：

• RED performance and stack resistance were studied by EIS and LSV.

关键词： Reverse electrodialysis     Electrochemical impedance spectroscopy     Concentration polarization     Spacer shadow effect    

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Preparation of Ni/SiO catalyst in ionic liquids for hydrogenation

FAN Qingming, LIU Yingxin, ZHENG Yifan, YAN Wei

《化学科学与工程前沿（英文）》 2008年 第2卷 第1期   页码 63-68 doi: 10.1007/s11705-008-0013-4

摘要： A series of silica supported nickel catalysts were prepared from nickel nitrate and tetraethyl orthosilicate by the sol-gel method with the imidazolium type ionic liquids as solvents. The catalysts were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Their catalytic performances for the selective hydrogenation of cinnamaldehyde to hydrocinnamaldehyde were investigated. The results show that the Ni/SiO catalyst prepared with 1-(2-hydroxyethyl)-3-methyl-imidazole tetrafluoroborate ionic liquid as solvent exhibits the highest catalytic activity for the reaction. Under the optimal conditions of catalyst dosage (based on the mass of cinnamaldehyde used) 10%, reaction pressure 2 MPa, temperature 373 K and reaction time 2 h, the conversion of cinnamaldehyde and the selectivity to hydrocinnamaldehyde can reach 97.6% and 98.8%, respectively.

关键词： dispersive     conversion     catalytic     2-hydroxyethyl     catalytic activity    

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Product lifecycle-oriented virtual assembly technology

LIU Jian-hua, NING Ru-xin, YAO Jun, WAN Bi-le

《机械工程前沿（英文）》 2006年 第1卷 第4期   页码 388-395 doi: 10.1007/s11465-006-0045-8

摘要： VA (virtual assembly) provides a more efficient, intuitive and convenient method for assembly process modeling, simulation and analysis. Previous researches about VA are almost isolated and dispersive, and have not established the understanding and definition of VA from a macroscopical and integrated view. Based on the analysis of the connotations of VA, a PLO-VATA (product lifecycle-oriented virtual assembly technology architecture) is proposed, in this architecture, VA is decomposed into four basic elements: principles and methodology of DFA (design for assembly), assembly analysis and evaluation, virtual assembly model and virtual assembly toolkits. Immersion, concurrence, integration and collaboration are the four main characteristics of VA being put forward. The key techniques of VA including virtual assembly model, virtual assembly analysis and evaluation, and virtual assembly process planning are discussed. Finally, a prototype system is built to validate the feasibility of the proposed method.

关键词： integrated     concurrence     feasibility     dispersive     assembly technology    

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Evidence from sorption kinetics, sequential extraction and extended X-ray absorption fine-structure spectroscopy

《环境科学与工程前沿（英文）》 2022年 第16卷 第9期 doi: 10.1007/s11783-022-1547-2

摘要：

• DPAA sorption followed pseudo-secondary and intra-particle diffusion models.

关键词： Diphenylarsinic acid (DPAA)     Sorption     Magnetite     Siderite     Sequential extraction     EXAFS    

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Studies on catalytic reduction of nitrate in groundwater

GENG Bing, ZHU Yanfang, JIN Zhaohui, LI Tielong, KANG Haiyan, WANG Shuaima

《环境科学与工程前沿（英文）》 2007年 第1卷 第3期   页码 357-361 doi: 10.1007/s11783-007-0061-x

摘要： Catalytic reduction of nitrate in groundwater by sodium formate over the catalyst was investigated. Pd-Cu/-AlO catalyst was prepared by impregnation and characterized by brunauer-emmett-teller (BET), inductive coupled plasma (ICP), X-ray diffraction (XRD), transmission electron microscopy (TEM) and energy dispersive X-ray (EDX). It was found that total nitrogen was effectively removed from the nitrate solution (100 mg/L) and the removal efficiency was 87%. The catalytic activity was affected by pH, catalyst amount used, concentration of sodium formate, and initial concentration of nitrate. As sodium formate was used as reductant, precise control in the initial pH was needed. Excessively high or low initial pH (7.0 or 3.0) reduced catalytic activity. At initial pH of 4.5, catalytic activity was enhanced by reducing the amount of catalyst, while concentrations of sodium formate increased with a considerable decrease in N selectivity. In which case, catalytic reduction followed the first order kinetics.

关键词： dispersive     electron microscopy     considerable decrease     Catalytic reduction     brunauer-emmett-teller    

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time monitoring of bioreactor mAb IgG3 cell culture process dynamics via Fourier transform infrared spectroscopy

Huiquan Wu, Erik Read, Maury White, Brittany Chavez, Kurt Brorson, Cyrus Agarabi, Mansoor Khan

《化学科学与工程前沿（英文）》 2015年 第9卷 第3期   页码 386-406 doi: 10.1007/s11705-015-1533-3

摘要： Compared to small molecule process analytical technology (PAT) applications, biotechnology product PAT applications have certain unique challenges and opportunities. Understanding process dynamics of bioreactor cell culture process is essential to establish an appropriate process control strategy for biotechnology product PAT applications. Inline spectroscopic techniques for real time monitoring of bioreactor cell culture process have the distinct potential to develop PAT approaches in manufacturing biotechnology drug products. However, the use of inline Fourier transform infrared (FTIR) spectroscopic techniques for bioreactor cell culture process monitoring has not been reported. In this work, real time inline FTIR Spectroscopy was applied to a lab scale bioreactor mAb IgG3 cell culture fluid biomolecular dynamic model. The technical feasibility of using FTIR Spectroscopy for real time tracking and monitoring four key cell culture metabolites (including glucose, glutamine, lactate, and ammonia) and protein yield at increasing levels of complexity (simple binary system, fully formulated media, actual bioreactor cell culture process) was evaluated via a stepwise approach. The FTIR fingerprints of the key metabolites were identified. The multivariate partial least squares (PLS) calibration models were established to correlate the process FTIR spectra with the concentrations of key metabolites and protein yield of in-process samples, either individually for each metabolite and protein or globally for all four metabolites simultaneously. Applying the 2 derivative pre-processing algorithm to the FTIR spectra helps to reduce the number of PLS latent variables needed significantly and thus simplify the interpretation of the PLS models. The validated PLS models show promise in predicting the concentration profiles of glucose, glutamine, lactate, and ammonia and protein yield over the course of the bioreactor cell culture process. Therefore, this work demonstrated the technical feasibility of real time monitoring of the bioreactor cell culture process via FTIR spectroscopy. Its implications for enabling cell culture PAT were discussed.

关键词： process analytical technology (PAT)     Fourier-transform infrared (FTIR) spectroscopy     partial least squares (PLS) regression     mouse IgG3     bioreactor cell culture process     real time process monitoring    

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Molecular diffusion in ternary poly(vinyl alcohol) solutions

《化学科学与工程前沿（英文）》 2022年 第16卷 第6期   页码 1003-1016 doi: 10.1007/s11705-021-2121-3

摘要： The diffusion kinetics of a molecular probe—rhodamine B—in ternary aqueous solutions containing poly(vinyl alcohol), glycerol, and surfactants was investigated using fluorescence correlation spectroscopy and dynamic light scattering. We show that the diffusion characteristics of rhodamine B in such complex systems is determined by a synergistic effect of molecular crowding and intermolecular interactions between chemical species. The presence of glycerol has no noticeable impact on rhodamine B diffusion at low concentration, but significantly slows down the diffusion of rhodamine B above 3.9% (w/v) due to a dominating steric inhibition effect. Furthermore, introducing surfactants (cationic/nonionic/anionic) to the system results in a decreased diffusion coefficient of the molecular probe. In solutions containing nonionic surfactant, this can be explained by an increased crowding effect. For ternary poly(vinyl alcohol) solutions containing cationic or anionic surfactant, surfactant–polymer and surfactant–rhodamine B interactions alongside the crowding effect of the molecules slow down the overall diffusivity of rhodamine B. The results advance our insight of molecular migration in a broad range of industrial complex formulations that incorporate multiple compounds, and highlight the importance of selecting the appropriate additives and surfactants in formulated products.

关键词： fluorescence correlation spectroscopy     poly(vinyl alcohol)     anomalous diffusion     crowding effects     dynamic light scattering     binding effects     rhodamine B    

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标题 作者 时间 类型 操作

Formation of coke in thermal cracking of jet fuel under supercritical conditions

ZHU Yuhong, YU Caixiang, LI Zimu, MI Zhentao, ZHANG Xiangwen

期刊论文

Factors influencing near infrared spectroscopy analysis of agro-products: a review

Xiao XU, Lijuan XIE, Yibin YING

期刊论文

Review: Tip-based vibrational spectroscopy for nanoscale analysis of emerging energy materials

Amun JARZEMBSKI, Cedric SHASKEY, Keunhan PARK

期刊论文

Terahertz time-domain spectroscopy of high-pressure flames

Jason BASSI, Mark STRINGER, Bob MILES, Yang ZHANG

期刊论文

Modeling of oil near-infrared spectroscopy based on similarity and transfer learning algorithm

Yifei Wang, Kai Wang, Zhao Zhou, Wenli Du

期刊论文

采用白光X射线源和模拟阵列能量色散阵列探测器的高通量粉末衍射技术

汪晓平, 董伟伟, 张鹏, 唐浩琪, 张澜庭, 杨铁莹, 刘鹏, 汪洪, 项晓东

期刊论文

Time of flight improved thermally grown oxide thickness measurement with terahertz spectroscopy

期刊论文

Cystine-assisted accumulation of gold nanoparticles on ZnO to construct a sensitive surface-enhanced Raman spectroscopy

期刊论文

configuration on interface resistances in reverse electrodialysis by in situ electrochemical impedance spectroscopy

期刊论文

Preparation of Ni/SiO catalyst in ionic liquids for hydrogenation

FAN Qingming, LIU Yingxin, ZHENG Yifan, YAN Wei

期刊论文

Product lifecycle-oriented virtual assembly technology

LIU Jian-hua, NING Ru-xin, YAO Jun, WAN Bi-le

期刊论文

Evidence from sorption kinetics, sequential extraction and extended X-ray absorption fine-structure spectroscopy

期刊论文

Studies on catalytic reduction of nitrate in groundwater

GENG Bing, ZHU Yanfang, JIN Zhaohui, LI Tielong, KANG Haiyan, WANG Shuaima

期刊论文

time monitoring of bioreactor mAb IgG3 cell culture process dynamics via Fourier transform infrared spectroscopy

Huiquan Wu, Erik Read, Maury White, Brittany Chavez, Kurt Brorson, Cyrus Agarabi, Mansoor Khan

期刊论文

Molecular diffusion in ternary poly(vinyl alcohol) solutions

期刊论文