资源类型

期刊论文 107

年份

2023 6

2022 14

2021 3

2020 9

2019 10

2018 13

2017 7

2016 6

2015 5

2014 3

2013 2

2012 1

2011 4

2010 4

2009 3

2008 5

2007 5

2002 1

2001 2

2000 1

展开 ︾

关键词

地球物理 2

BFT 1

VO2薄膜 1

X射线自由电子激光 1

“1123”生态环保排放限值 1

一氧化碳氧化 1

三峡工程 1

三态组织 1

中试平台 1

仅1吸收 1

傅立叶红外光谱 1

傅里叶变换红外成像 1

催化剂活化 1

光加热 1

光学透明 1

冲刷 1

分子荧光光谱 1

创客 1

剪切波 1

展开 ︾

检索范围:

排序: 展示方式:

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    

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    

Near-infrared benzodiazoles as small molecule environmentally-sensitive fluorophores

《化学科学与工程前沿(英文)》 2022年 第16卷 第1期   页码 128-135 doi: 10.1007/s11705-021-2080-8

摘要: The development of fluorophores emitting in the near-infrared spectral window has gained increased attention given their suitable features for biological imaging. In this work, we have optimised a general and straightforward synthetic approach to prepare a small library of near-infrared-emitting C-bridged nitrobenzodiazoles using commercial precursors. C-bridged benzodiazoles have low molecular weight and neutral character as important features that are not common in most near-infrared dyes. We have investigated their fluorescence response in the presence of a wide array of 60 different biomolecules and identified compound 3i as a potential chemosensor to discriminate between Fe2+ and Fe3+ ions in aqueous media.

关键词: fluorescence     probes     iron     screening     library    

Real time monitoring of bioreactor mAb IgG3 cell culture process dynamics via Fourier transform infraredspectroscopy: Implications for enabling cell culture process analytical technology?

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    

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    

Establishing two-stage interaction between fly ash and NaOH by X-ray and infrared analyses

Bhagwanjee JHA,Nevin KOSHY,Devendra Narain SINGH

《环境科学与工程前沿(英文)》 2015年 第9卷 第2期   页码 216-221 doi: 10.1007/s11783-014-0630-8

摘要: The interaction of the fly ash and NaOH, in an open reflux hydrothermal system at 100°C, has been explored by several researchers and formation of fly ash zeolites has been confirmed based on the X-ray diffraction analysis of the residues. However, this method does not reveal much about the characteristic transitions (viz. elemental, electro-negativity and cation exchange capacity) of the residues. In this situation, resorting to Fourier transform-infrared radiation (FT-IR) spectroscopy on the residues obtained from two-stage hydrothermal treatment process, described in this manuscript, appears to be a novel idea to establish transitions in chemical bonds (viz., -Si-OH-Al-, OH-Na, OH-Al-), crystallinity and cation exchange capacity of these residues. Based on extensive studies, it has been demonstrated that FT-IR spectroscopy is extremely useful for 1) detection of chemical bonds in the residues, 2) evaluation of zeolites in the residues and 3) also establishing the superiority of the two-stage interaction of the fly ash with NaOH for synthesizing better fly ash zeolites (viz., Na-P1 and Hydroxysodalte) as compared to those obtained from the conventional single-stage treatment of the fly ash.

关键词: hydrothermal treatment     alkali activation     fly ash zeolites     X-ray diffraction (XRD) and Fourier transform-infrared radiation (FT-IR) spectroscopy    

Near-infrared fluorescent probe for fast track of cyclooxygenase-2 in Golgi apparatus in cancer cells

Bhaskar Gurram, Miao Li, Jiangli Fan, Jingyun Wang, Xiaojun Peng

《化学科学与工程前沿(英文)》 2020年 第14卷 第1期   页码 41-52 doi: 10.1007/s11705-019-1796-1

摘要: Cyclooxygenase-2 (COX-2) has been used as an excellent traceable biomarker, and exists maximally in Golgi apparatus (Cancer cells). Celecoxib (CCB) is a selective inhibitor for COX-2, and has been used as one of non-steroidal anti-inflammatory drug. Herein we report the conjugation of nile blue (NB) with CCB via a six-carbon linkage to form a fluorescence probe NB-C6-CCB for the detection of COX-2. NB-C6-CCB displays strong fluorescence with the emission peak centered at near-infrared wavelength (700 nm) in tumor cells or tumor tissues with high expression of COX-2. Importantly, NB-C6-CCB can discriminate cancer cells (MCF-7) fluorescence intensity from normal ones (COS-7) in the co-culture medium under confocal microscope. Subcellular localization of the NB-C6-CCB preferentially points to the Golgi apparatus and increases the fluorescent intensity. The competitive analysis (with CCB) and Native-PAGE analysis confirmed that NB-C6-CCB shows selective binding affinity towards COX-2 enzyme. Competitive analysis with CCB (flow cytometry assay) revealed the fluorescence intensity fluctuation due to pretreatment of CCB with different concentrations, indicating that the NB-C6-CCB is a precise or sensitive probe for the COX-2. Tumor tissue (depth: 500 µm), organs and mice imaging tests show excellent near-infrared visualization, specific localization and identification of tumors.

关键词: cyclooxygenase-2     nile blue     CCB     Golgi apparatus     NIR imaging    

Application of spectral technology in flame measurement

Jiaxun LIU, Xiaoshu CAI, Zenghao ZHU, Huinan YANG

《能源前沿(英文)》 2014年 第8卷 第1期   页码 138-143 doi: 10.1007/s11708-013-0283-5

摘要: Spectral technology has become an important detection method due to its advantages such as non-intrusive measurement and on-line analysis. In this paper, two applications of spectral technology in thermal detection were proposed. First, a novel spectroscopic method based on Planck’s law for measurement of emissivity was introduced. The emissivity, obtained by comparing the radiation intensity of the blackbody which had the same temperature as the flame with the detected intensity of the flames, could be used for on-line measurements and had a relatively higher upper temperature limit. Then, a spectroscopic method for composition detection of blended fuels was proposed based on the emissivity measured. By comparing the spectra of blended fuels and single fuels, the ratio of single fuels of the blended fuel could be calculated. The measurement system proposed in this paper, which consists of a spectrometer and a computer, is very compact.

关键词: spectrum     emissivity measurement     component of fuel     near-infrared spectrometer    

Predicting the elemental compositions of solid waste using ATR-FTIR and machine learning

《环境科学与工程前沿(英文)》 2023年 第17卷 第10期 doi: 10.1007/s11783-023-1721-1

摘要:

● A method based on ATR-FTIR and ML was developed to predict CHNS contents in waste.

关键词: Elemental composition     Infrared spectroscopy     Machine learning     Moisture interference     Solid waste     Spectral noise    

A combined experimental and theoretical study of micronized coal reburning

Hai ZHANG, Jiaxun LIU, Jun SHEN, Xiumin JIANG

《能源前沿(英文)》 2013年 第7卷 第1期   页码 119-126 doi: 10.1007/s11708-012-0226-6

摘要: Micronized coal reburning (MCR) can not only reduce carbon in fly ash but also reduce NO emissions as compared to the conventional coal reburning. However, it has two major kinetic barriers in minimizing NO emission. The first is the conversion of NO into hydrogen cyanide (HCN) by conjunction with various hydrocarbon fragments. The second is the oxidation of HCN by association with oxygen-containing groups. To elucidate the advantages of MCR, a combination of Diffuse Reflection Fourier Transform Infrared (FTIR) experimental studies with Density Functional Theory (DFT) theoretical calculations is conducted in terms of the second kinetic barrier. FTIR studies based on Chinese Tiefa coal show that there are five hydroxide groups such as OH-π, OH-N, OH-OR , self-associated OH and free OH. The hydroxide groups increase as the mean particle size decreases expect for free OH. DFT calculations at the B3LYP/6-31 G(d) level indicate that HCN can be oxidized by hydroxide groups in three paths, HCN+OH→HOCN+H (path 1), HCN+OH→HNCO+H (path 2), and HCN+OH→CN+H O (path 3). The rate limiting steps for path 1, path 2 and path 3 are IM2→P1+H (170.66 kJ/mol activated energy), IM1→IM3 (231.04 kJ/mol activated energy), and R1+OH→P3+H O (97.14 kJ/mol activated energy), respectively. The present study of MCR will provide insight into its lower NO emission and guidance for further studies.

关键词: hydroxyl radicals     Fourier transform infrared spectroscopy (FTIR)     density functional theory (DFT)     homogeneous reaction mechanism     NOx    

Understanding the behavior of recycled aggregate concrete by using thermogravimetric analysis

Subhasis PRADHAN, Shailendra KUMAR, Sudhirkumar V. BARAI

《结构与土木工程前沿(英文)》 2020年 第14卷 第6期   页码 1561-1572 doi: 10.1007/s11709-020-0640-5

摘要: The physio-chemical changes in concrete mixes due to different coarse aggregate (natural coarse aggregate and recycled coarse aggregate (RCA)) and mix design methods (conventional method and Particle Packing Method (PPM)) are studied using thermogravimetric analysis of the hydrated cement paste. A method is proposed to estimate the degree of hydration ( ) from chemically bound water ( ). The PPM mix designed concrete mixes exhibit lower . Recycled aggregate concrete (RAC) mixes exhibit higher and after 7 d of curing, contrary to that after 28 and 90 d. The chemically bound water at infinite time ( ) of RAC mixes are lower than the respective conventional concrete mixes. The lower , Ca(OH) bound water, free Ca(OH) content and FT-IR analysis substantiate the use of pozzolanic cement in the parent concrete of RCA. The compressive strength of concrete and cannot be correlated for concrete mixes with different aggregate type and mix design method as the present study confirms that the degree of hydration is not the only parameter which governs the macro-mechanical properties of concrete. In this regard, further study on the influence of interfacial transition zone, voids content and aggregate quality on macro-mechanical properties of concrete is needed.

关键词: recycled aggregate concrete     Particle Packing Method     thermogravimetric analysis     chemically bound water     degree of hydration     Fourier transform infrared spectroscopy    

Pyrolysis behaviors of oil sludge based on TG/FTIR and PY-GC/MS

Wei SONG, Jianguo LIU, Yongfeng NIE,

《环境科学与工程前沿(英文)》 2010年 第4卷 第1期   页码 59-64 doi: 10.1007/s11783-009-0152-y

摘要: Pyrolysis is an alternative technology for oil sludge treatment. Thermogravimetric Analysis-Fourier Transform Infrared Spectroscopy and Pyrolysis-Gas Chromatography/Mass Spectrometry were employed to investigate the pyrolysis process and products of oil sludge. The pyrolysis process was divided into five stages: drying and gas desorption, oil volatilization, main pyrolysis, semi-coke charring, and mineral decomposition. The main reaction temperatures ranged from 497.6 K to 753.2 K. The products were mainly composed of pairs of alkane and alkene (carbon number ranges from 1 to 27). The mechanisms consisted of random chain scission followed by end chain scission at high temperatures with volatilization occurring during the whole process. This study is useful not only for the proper design of a pyrolysis system, but also for improving the utilization of liquid oil products.

关键词: oil sludge     pyrolysis     Thermogravimetric Analysis-Fourier Transform Infrared Spectroscopy (TG-FTIR)     Pyrolysis-Gas Chromatography/Mass Spectrometry (PY-GC/MS)    

Laboratory investigation of emulsified asphalt binder modified with wood-derived nano-cellulose and nano paper-cellulose

Yunge WEI; Jiayu WANG; Ruoyu LI; Ling XU; Feipeng XIAO

《结构与土木工程前沿(英文)》 2022年 第16卷 第11期   页码 1474-1485 doi: 10.1007/s11709-022-0869-2

摘要: Emulsified asphalt is the primary material for preventive maintenance and cold-mix paving, but its low cohesive strength and poor mechanical properties limit its wide application, even with polymer modification. In this study, Styrene-Butadiene Rubber (SBR) emulsified asphalt was modified with nano-cellulose materials, namely nano paper-cellulose (NPC) and wood-derived nano-cellulose (WDC), to improve its properties. A novel preparation method of nano-cellulose solution was developed, including blending, ultrasonic stirring, and centrifugal treatment. Four types of nano-cellulose solution (0.5% NPC, 0.5%, 1.0%, and 1.5% WDC by weight of water) were selected. The microscopy analysis indicated that 0.5% WDC emulsion had a smaller particle size than 1.5% WDC emulsion. The rheology test indicated that WDC modified residue improved rutting resistance with the increased solution dosage due to the cross-linking effect, but its creep-and-recovery performance was worse than that of SBR emulsion residue. The NPC modified binder had a higher rutting factor than WDC modified binder at the same dosage after short-term aging. In addition, 1.0% WDC could be regarded as the optimal dosage in terms of fatigue and low-temperature performance. Furthermore, Fourier Transform Infrared Spectroscopy (FTIR) results showed that 0.5% NPC modified residue performed better in long-term aging resistance compared with 0.5%WDC modified asphalt.

关键词: nano-cellulose     emulsified asphalt binder     dispersion     rheological properties     Fourier transform infrared spectroscopy    

新型高黏度改性沥青的研发和应用

杨林江

《中国工程科学》 2008年 第10卷 第12期   页码 92-96

摘要:

针对杭州湾大桥桥面铺装对高黏度改性沥青的技术要求,研发了一种新型高黏度改性沥青[1]。通过分析基质沥青、SBS、化学助剂的红外光谱,在研究沥青改性过程中微观结构变化规律的基础上,提出了采用SBS加化学接枝反应剂(增黏剂)TW-1和增容剂TW-2的沥青改性配伍设计,使改性沥青在提高低温延度、弹性恢复能力的同时,大幅度提升了60 ℃动力黏度,而施工和易性不受影响,产品在杭州湾大桥工程中得到了成功的应用。

关键词: 杭州湾大桥     高黏度改性沥青     配伍机理     红外光谱分析     路用性能     施工性能    

碱处理对桉木纤维挤压结合机理的影响

彭万喜,林芝,李年存

《中国工程科学》 2014年 第16卷 第4期   页码 64-68

摘要:

采用桉木纤维为原料,探讨碱处理对板材挤压结合机理的影响。结果表明:碱处理对木质素、半纤维素都有不同程度的降解作用;在热压制板过程中,经过降解作用的木材成分经适当的热压工艺能够发生聚合反应从而粘合成板;强碱(NaOH)对桉木纤维的影响大于弱碱溶液(Na2CO3),且处理时间为10 h 较适宜;碱处理过程产生的活性羟基,热压后可以缔合形成氢键,增加了纤维之间的结合力,有利于桉木纤维自身粘合成板。

关键词: 桉木纤维     碱处理     傅立叶红外光谱     扫描电子显微镜(SEM)    

标题 作者 时间 类型 操作

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

Xiao XU, Lijuan XIE, Yibin YING

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

Near-infrared benzodiazoles as small molecule environmentally-sensitive fluorophores

期刊论文

Real time monitoring of bioreactor mAb IgG3 cell culture process dynamics via Fourier transform infraredspectroscopy: Implications for enabling cell culture process analytical technology?

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

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

Establishing two-stage interaction between fly ash and NaOH by X-ray and infrared analyses

Bhagwanjee JHA,Nevin KOSHY,Devendra Narain SINGH

期刊论文

Near-infrared fluorescent probe for fast track of cyclooxygenase-2 in Golgi apparatus in cancer cells

Bhaskar Gurram, Miao Li, Jiangli Fan, Jingyun Wang, Xiaojun Peng

期刊论文

Application of spectral technology in flame measurement

Jiaxun LIU, Xiaoshu CAI, Zenghao ZHU, Huinan YANG

期刊论文

Predicting the elemental compositions of solid waste using ATR-FTIR and machine learning

期刊论文

A combined experimental and theoretical study of micronized coal reburning

Hai ZHANG, Jiaxun LIU, Jun SHEN, Xiumin JIANG

期刊论文

Understanding the behavior of recycled aggregate concrete by using thermogravimetric analysis

Subhasis PRADHAN, Shailendra KUMAR, Sudhirkumar V. BARAI

期刊论文

Pyrolysis behaviors of oil sludge based on TG/FTIR and PY-GC/MS

Wei SONG, Jianguo LIU, Yongfeng NIE,

期刊论文

Laboratory investigation of emulsified asphalt binder modified with wood-derived nano-cellulose and nano paper-cellulose

Yunge WEI; Jiayu WANG; Ruoyu LI; Ling XU; Feipeng XIAO

期刊论文

新型高黏度改性沥青的研发和应用

杨林江

期刊论文

碱处理对桉木纤维挤压结合机理的影响

彭万喜,林芝,李年存

期刊论文