PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2020
·Vol. 22
·期 32
·17791-17797
·
IF 3.43
Ligang Chen,Guanhua Ren,Liyuan Liu,Pan Guo,Endong Wang,Zhongjie Zhu,Jinrong Yang,Jianxiong Shen,Zongchang Zhang,Lu Zhou,Jianbing Zhang,Bin Yang,Weili Zhang,Yi Gao,Hongwei Zhao,Jiaguang Han
The cooling-induced formation of a hydrate in aqueous NaCl solutions was probed using terahertz time-domain spectroscopy (THz-TDS). It was found that the NaCl hydrate formation is accompanied by the emergence of four new absorption peaks at 1.60, 2.43, 3.34 and 3.78 THz. Combining X-ray diffraction measurements with solid-state based density functional theory (DFT) calculations, we assign the observed terahertz absorption peaks to the vibrational modes of the formed NaCl·2H2O hydrate during cooling. This work shows that THz-TDS based analysis has great potential in studying ionic hydrates and the newly revealed collective vibrational modes could be sensitive indicators to achieve quantitative analysis in phase transitions and lattice dynamics.
研究领域:
物理化学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2025
·
IF 4.7
Ting Zhang,Zhenqi Zhu,Yujing Bian,Xun Zhang,Lvzhu Cheng,Hao Qin,Bin Yang
Tryptophan, as an essential amino acid, can only be obtained through diet, and its production and processing are accompanied by different degrees of oxidation leading to poor absorption. Therefore, it is important to pay attention to the degree of oxidation of tryptophan promptly. Conventional tests can assess tryptophan oxidation levels by monitoring the amount of tryptophan, but most require complex pre-processing and time-consuming testing procedures. Based on this, we propose a rapid method to estimate the degree of tryptophan oxidation using terahertz spectroscopy. We confirmed the relationship between the terahertz characteristic absorption peaks of tryptophan and its content combined with X-ray diffraction and infrared spectroscopy. It was further found that the tryptophan content could be effectively determined based on the characteristic peak area. The findings of this study offer a novel and practical technique for quickly determining the level of tryptophan oxidation in food or dietary supplements.
研究领域:
食品科学
·
生物化学
·
光谱学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER TESTING
·
2017
·
IF 2.464
Jianxi Huang,Haijun Yang,Min Chen,Te Ji,Zhengchi Hou,Minghong Wu
Systematic study of FTIR spectra was carried out on the PES/PVP blends and PES-g-PVP copolymers . In the blends, no shift of carbonyl group absorbance was observed. In the copolymers, there was an occurrence of blue-shift that increases with the grafting degree, which can be used as a compelling evidence of PVP being grafted onto PES . This phenomenon was interpreted from the stereo-hindrance effect. Besides, as the intensity of carbonyl group absorbance increased proportionally with the degree of grafting obtained by elementary analysis, FTIR, a simple and easy tool, became feasible for the quantitative determination of PVP content in the graft copolymers . Calibration curves with high correlation coefficient were established from which the quantitative relationship between the intensity of carbonyl group absorbance normalized by a chosen internal reference and the grafting degree can be obtained.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Building Engineering
·
2023
·
IF 6.4
Xuelei Jiang,Ying Xu,Enen Li,Tianwu Wang,Wenyu Xie
Corrosion of steel materials (such as rebars and steel plates) usually occurs under coating materials . It is, with the existing non-destructive testing (NDT) technologies, difficult to accurately determine the corrosion of steel materials. The terahertz (THz) electromagnetic waves can penetrate the non-polar materials, and theoretically experience an absorption resonance with some corrosion products crystals ( i.e. , iron oxides). The THz spectroscopy has, therefore, a great application potential to characteristically identify the corrosion of steel materials. In the present study, the optical parameters and, especially, the positions of the characteristic absorption peaks of the corrosion products were systematically investigated and identified using the THz system. The experimental results showed that the refractive index of the different corrosion product samples was in the range of 2.7–3.4 in the effective frequency range of 0 THz - 1.2 THz, and the content of Fe 3 O 4 had a large influence on the optical parameters in the corrosion product mixtures. To measure the characteristic absorption peaks of the corrosion products, the effective frequency range was extended to 0 THz - 10 THz by an assembled broadband THz system. Within this range, the positions of the characteristic absorption peaks were identified as 3.4 THz, 4.2 THz, 4.85 THz, and 5.8 THz for Fe 2 O 3 , and as 3.6 THz, 4.05 THz, 5 THz, and 5.45 THz for α-FeOOH. For Fe 2 O 3 and α-FeOOH, the intensities of the absorption peaks at 4.85 THz and 3.6 THz, respectively, showed a linear relationship with the mass content. Furthermore, the THz spectroscopy could accurately identify Fe 2 O 3 and α-FeOOH in the corrosion product mixtures by comparing with the results from IR spectroscopy and Raman spectroscopy. This means that the occurrence of steel corrosion could be detected according to the characteristic absorption peaks of Fe 2 O 3 and α-FeOOH. The experimental results provide a basis for the application of THz spectroscopy in the NDT of the corrosion of steel materials.
研究领域:
材料科学
·
无损检测
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2015
·Vol. 7
·期 29
·12706-12712
·
IF 7.394
Shuai Ye,Jun Song,Yuliang Tian,Linchun Chen,Dong Wang,Hanben Niu,Junle Qu
The ability to control the local surface plasmonic resonance (LSPR) absorption peaks of silver nanoparticles will greatly broaden the scope of their practical application. Conventional methods tune the LSPR peaks by modifying the shape or size of the silver nanoparticles. Here, we present a novel method to tune the LSPR band by controlling the particle corner sharpness. A modified photochemical method was used to prepare silver nanoparticles. It was found that the nanoparticles irradiated using light-emitting diodes (LEDs) with a wavelength of 455 nm were decahedral, although the reaction temperature was different. However, the in-plane dipole LSPR peak of the as-prepared silver nanodecahedra exhibited an evident red shift from 460 nm to 500 nm during the synthesis process, and the wavelength of the LSPR peak increased linearly as the reaction time increased. A numerical simulation conducted to investigate the mechanism behind the shift revealed that the red shift of the LSPR peak was mainly induced by the evolution of the corner sharpness of the silver nanodecahedra. These results demonstrated the effectiveness of the method in precisely tuning the LSPR peak by controlling the reaction time. By turning off the irradiation light, the photochemical process could be immediately terminated, and the LSPR peak of the silver nanoparticles remained constant. Compared with conventional methods, the present tuning precision can reach 1 nm.
研究领域:
纳米材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Science China-Materials
·
2022
·Vol. 65
·期 6
·1687-1695
·
IF 8.64
Zong Jianpeng,Ren Quan,Tian Xiaoli,Xiang Ting,Feng Yuhua,Chen Hongyu
Surface ligands play critical roles in nano-synthesis and thus it is of great importance in expanding the scope of suitable ligands. In this work, we explore phenynyl ligands in modulating the Au-Au interface when growing Au domains on Au seeds. A patchy growth mode is observed where the emerging islands are flat-laying with holes and branches. This growth mode is distinctively different from the conventional facet-controlled growth using weak ligands, and the non-wetting island growth using strong ligands. Through manipulating the molecular structure and the packing of the phenynyl ligands on the Au seeds, the overgrown Au domains are continuously tuned, from patches to islands, extending the plasmon absorption peak into the near-infrared spectral range. We believe that the new ligand with intermediate affinity and the unusual growth mode would expand the control in both synthesis and application.
研究领域:
纳米材料科学
·
化学合成
·
光学性质研究
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Xincheng Cai,Junjing Duan,Zhangyi Huang,Zhenyu Zhang,Shengquan Yu,Xiaoqiang Li,Jianqi Qi,Tiecheng Lu
Y 2 O 3 -MgO composites are promising for mid-infrared windows and domes in harsh environments. However, the insufficient transmittance range (the transmittance >30 % only in ∼2–7 μm) and strong absorption peak (the transmittance <32 % at 7.0 μm) of Y 2 O 3 -MgO composites severely limit their application range because of agglomerations and carbon contamination from organics in the raw materials, currently. In this study, utilizing carbon-free raw materials and high molecular motions, the reduction of carbon contamination and agglomerations within the as-synthesized nanopowers was achieved via the modified co-precipitation synthesis. A highly mid-infrared transparent (the maximum transmittance of 79 % at 6.0 μm) Y 2 O 3 -MgO composite with wide transmittance range (the transmittance >30 % in 2.2–9.7 μm) and weak absorption peaks (the transmittance ≈68.57 % at 7.0 μm) was fabricated by the hot-pressing sintering method using the as-obtained nanopowders in the absence of exogenous dopants. And the modified co-precipitation synthesis is a method with great potential for the development of mid-infrared transparent Y 2 O 3 -MgO composites with wide transmittance range and weak absorption peaks.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
SENSORS
·
2021
·Vol. 21
·期 24
·8292
·
IF 3.576
Kaixuan Li,Ding Li,Yan Zhang
Applications of terahertz time-domain spectroscopy (THz-TDS) in the fields of chemistry and biomedicine have recently received increased attention. Specifically, THz-TDS is particularly effective for the identification of alkaloid molecules, because it can distinguish the vibration types of base molecules in the THz band and provide a direct characteristic spectrum for the configuration and conformation of biomolecules. However, when THz-TDS technology is used to identify alkaloid molecules, most of them are concentrated in the 0.1–3.0 THz band, limiting the amount of information that can be obtained. In this work, a wide-spectrum THz-TDS system was independently built to explore the absorption spectra of uracil and its 5-substituents in the range of 1.3–6.0 THz. We found that, in the THz band, uracil and its 5-substituents have similar absorption peaks near 4.9 and 3.3 THz, while the 5-substituents have an additional absorption peak in the range of 1.5–2.5 THz. This absorption peak is red-shifted as the relative atomic mass of the 5-substituted atoms increases. Gaussian software was adopted to calculate the absorption spectra of the samples. The simulation conclusions were in good agreement with the experimental results, revealing that the vibration of the base molecule at low frequencies can be attributed to the inter-molecular vibration. This work demonstrates that THz-TDS technology can be used to accurately identify biomolecules with similar molecular structures, reflecting the importance of molecular structure in biological activity.Keywords:terahertz time domain spectroscopy;absorption peaks;5-substituents of uracil;vibration;broad spectrum;molecular structures
研究领域:
化学
·
生物医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2018
·
IF 5.667
Mengxin Zhao,Haili Yu,Yi He
We present a dynamic multichannel colorimetric sensor array for highly effective discrimination of ten explosives, including 2,4-dinitrotoluene, picric acid, hexahydro-1,3,5-trinitro-1,3,5-triazine, 3-nitro-1,2,4-triazol-5-one, hexanitrohexaazaisowurtzitane, 2,6-diamino-3,5-dinitropyrazine-1-oxide, 1,1-diamino-2,2-dinitroethene, 4-nitrophenol, nitroguanidine, and 2,4-dinitrophenol. This sensor array is based on the fact that the reduction of indigo carmine by dithiothreitol generates semi-leucoindigo carmine and leucoindigo carmine at the different reaction time, resulting in abundantly available absorption peaks at 456 nm, 504 nm, 552 nm, 612 nm, 754 nm, and 906 nm as the sensing elements. Because of the presence of the supramolecular interactions and chemical reactions between explosives and indigo carmine, the distinct absorbance responses to each explosive are created as an analytical fingerprint to discriminate and identify ten explosives. The present colorimetric sensor array can efficiently discriminate individual explosive at a concentration of 1.5 μM and binary explosive mixtures. Additionally, this sensor array has the capability to identify individual explosive in real water samples.
研究领域:
分析化学
·
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2016
·
IF 1.78
Tianyang Wang,Haiya Sun,Ting Lu,Krithanthi C. Weerasinghe,Dongzhi Liu,Wenping Hu,Xueqin Zhou,Lichang Wang,Wei Li,Lizeng Liu
It is proved that introducing the ethyl substituted group to 1-amino will enhance the intramolecular charge transfer ( ICT ) process of 1-N substituted anthraquinone derivatives. Bathochromic shift of the absorption maxima and diminished absorption intensity are observed with the increase of the electron donation abilities of the N-ethyl groups. Moreover, the intramolecular and intermolecular hydrogen bonds further intensify the ICT properties through introducing the end amino group. This work exhibits more effective acceptors than anthraquinone in novel multichromophore materials for organic solar cells and other optoelectronic devices.
研究领域:
有机化学
·
材料科学
·
光电子学
✓ 已验证
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2025
·
IF 6.2
Xincheng Cai,Junjing Duan,Zhangyi Huang,Lexing Liang,Zhenyu Zhang,Mao Deng,Jianqi Qi,Tiecheng Lu
Y 2 O 3 MgO composites have emerged as promising mid-infrared (MIR) materials owing to their exceptional broadband transmittance and remarkable thermal stability at elevated temperatures. Nevertheless, the presence of uncontrollable absorption bands within the 4–7 μm spectral range, compromises their optical performance in advanced MIR systems. To address this limitation, we systematically investigated annealing as a strategic approach for modulating defect chemistry in oxide composites. In this paper, the absorption peaks of Y 2 O 3 MgO composites were controlled by varying the annealing conditions. As the annealing temperature increases from 600 °C to 1100 °C, the absorption peaks of Y 2 O 3 MgO composites gradually shift from ∼4.9 μm to ∼6.8 μm, with a transition temperature ∼900°C. This behavior is attributed to the oxidation of metal-organic coordination (MOC) to CO 3 2- in high-temperature air. Ultimately, Y 2 O 3 MgO composites featuring controllable absorption peaks were obtained, demonstrating a transmittance of ∼81 % at 7 μm - the highest value ever reported for this composite system, which broadens the potential application space, particularly in fields requiring mid-infrared transparency such as gas detection, materials characterization, and biomedical imaging. This study not only elucidates specific strategies for enhancing the performance and microstructure of Y 2 O 3 MgO composites but also furnishes reliable methodologies and datasets to support the annealing processes of other material systems.
研究领域:
材料科学
·
光学材料
·
陶瓷
·
红外技术
·
固态化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2025
·
IF 11.3
Shuang Su,Zhiyang Zhang,Jiadong Chen,Yan Chen,Xin Cao,Shuoyang Yan,Ranran Yu,Jie Shao,Xiaokun Wang,Jaebum Choo,Lingxin Chen
On-site detection of hydrogen sulfide (H 2 S), a toxic byproduct of microbial decomposition, is essential for environmental surveys, sewage tracing, and occupational safety. While existing gold nanorods (Au NRs)-based colorimetric methods offer portability and sensitivity, their practicality is hindered by the instability of enzymes and colloidal nanoparticles. Herein, we present an enzyme-free, portable H 2 S detection device using Au NRs powder, ensuring highly sensitive and reliable colorimetric detection while enhancing long-term applicability. The sensing strategy involves two steps: H 2 S microextraction and colorimetric assay. First, H 2 S is accumulated into a NaOH aqueous drop from a complex sample matrix via headspace single-drop microextraction (HS-SDME) using sulfamic acid. In the colorimetric assay, dissolved H 2 S reduces KIO 3 to I 2 in glycine-HCl buffer (pH 2.6), which etches Au NRs in the presence of Br - and CTA + , causing a blue shift in the plasmon band with a distinct color change. This method achieves a visual detection limit of 0.05 µM, approximately 10 times lower than the Methylene Blue method. The use of HS-SDME ensures excellent selectivity against co-existing ions (≥10-fold) and small organic molecules (100-fold). Validation with real samples yielded recoveries of 92.40 %-109.51 %, demonstrating reliability in environmental monitoring and river pollution tracing. To simplify detection, we developed a liquid-free test kit containing an H 2 S microextraction tube (sulfamic acid powder), a colorimetric assay tube (Au NRs powder and solid buffer), and a portable heating device. This enzyme-free sensor ensures long-term stability and practicality, advancing Au NRs-based sensors for environmental monitoring.
研究领域:
环境科学
·
分析化学
·
纳米技术
·
传感技术
·
水污染监测
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）