Spectrochim Acta A Mol Biomol Spectrosc
October 2024
In this study, we have investigated the structural stability of terephthalamide (TPA) crystal at pressure from ambient to 15 GPa in the diamond anvil cell at room temperature by Raman spectroscopy. Assignment for the Raman vibration modes of TPA crystal at ambient conditions has been performed based on the density functional theory (DFT) calculations. Pressure-induced structural transition was monitored using in-situ Raman spectroscopy.
View Article and Find Full Text PDFIsobutyramide (IBA) has attracted considerable attention due to its expansive prospects for practical applications in the synthesis of drugs, dyes and other organic compounds. Herein we perform the high-pressure studies of IBA crystal by Raman spectral measurements at room temperature from ambient pressure to 30 GPa by using diamond anvil cells (DACs) to gain comprehensive insights into its structure and stability. Raman vibrational modes of IBA crystal at ambient pressure are resolved based on the experimental results and the first-principles theoretical calculations.
View Article and Find Full Text PDFLithium perchlorate (LiClO), as one of the new high-energy oxidizers, is chosen for high pressure Raman research to gain a better understanding of the structure and stability, which is very important for the performance of an explosive. Raman spectra of LiClO crystal have been measured from ambient to 25.07 GPa with diamond anvil cells (DACs) at room temperature to investigate the structural stability of this system.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
January 2023
Raman spectroscopy and stimulated Raman scattering (SRS) were used to investigate the hydrogen bonding (HB) network in 1,2-propanediol (1,2-PD)-water binary solutions. Abnormal changes in hydrogen bonds (HBs) were detected when V (volume fraction of the1,2-PD) was 0.4.
View Article and Find Full Text PDFAqueous zinc-ion batteries (ZIBs) are considered as one of the ideal devices for large-scale energy storage because of their safety, low cost, and nontoxicity. Unfortunately, the choice of cathode materials for ZIBs is still limited. Herein, a novel oxygen vacancy-rich nitrogen-doped MnCO (MnCO@N) microsphere is reported as a cathode material for rechargeable ZIBs, which displays a relatively high reversible capacity of 171.
View Article and Find Full Text PDFWe investigate the orbital angular momentum of vortex light in a six-level atomic system with a closed loop. We find that a vortex light field via four-wave mixing (FWM) is sensitive to the relative phase of the driving fields due to forming a closed loop configuration. Thus, it could periodically tune the phase and intensity of the vortex FWM field by adjusting the relative phase of the driving fields.
View Article and Find Full Text PDFMacromol Rapid Commun
March 2022
Plasticization is a critical challenge in membrane-based gas separation. Here a novel fluoropolymer, poly(trifluoro styrene) (PTFS), is reported for hydrogen separation from hydrocarbons. The polymer structure is first characterized by different techniques such as nuclear magnetic resonance (NMR) and positron annihilation lifetime spectroscopy (PALS).
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
February 2021
We report the low-temperature studies of liquid CHCN by Raman spectral measurements at ambient pressure with decreasing the temperature from 20 to -196 °C. Detailed internal modes especially the lattice modes analysis revealed that the structural phase transitions of acetonitrile from liquid to solid phase β and solid phase β to solid phase α were occurring at -50 and -60 °C, respectively. Further, the Fermi resonance parameters between the fundamental ν and combination (ν + ν) of CHCN at different temperatures were calculated based on the Bertran's equations.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
January 2020
The Raman spectra of acetonitrile-LiClO mixture solution have been measured in the temperature range 20 to -196 °C at ambient pressure. Detailed Raman spectroscopy analysis revealed that, in acetonitrile-LiClO mixture solution, the liquid CHCN transformed into solid phase β at approximately -50 °C, and then into solid phase α at approximately -60 °C. Besides, the Fermi resonance parameters of CHCN and CHCN---Li complex at different temperatures were calculated by using the Bertran's equations, respectively.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
January 2019
Raman spectra of the solution of LiClO in acetonitrile (CHCN) at different concentrations have been measured. With increasing the concentration of Li, it was noted that several vibrational modes of CHCN had significant changes in Raman shifts and some new Raman peaks emerged due to the CHCN⋯Li complex formation. In addition, Fermi resonance phenomenon between the ν and (ν + ν) Raman bands of CHCN⋯Li complex was observed.
View Article and Find Full Text PDFFocal adhesion kinase (FAK) has long been considered to be a key regulator of growth factor receptor- and integrin-mediated signals, with pivotal roles in tumor cells through its kinase activity and scaffolding function. Increased FAK expression and activity has been observed in tumors of various origins and is often associated with a poor prognosis. However, there have been no studies on the aberrant expression of FAK in thymic epithelial tumors to date.
View Article and Find Full Text PDFTungsten ditelluride (WTe ) is a semimetal with orthorhombic T phase that possesses some unique properties such as Weyl semimetal states, pressure-induced superconductivity, and giant magnetoresistance. Here, the high-pressure properties of WTe single crystals are investigated by Raman microspectroscopy and ab initio calculations. WTe shows strong plane-parallel/plane-vertical vibrational anisotropy, stemming from its intrinsic Raman tensor.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
February 2017
Guang Pu Xue Yu Guang Pu Fen Xi
March 2015
Fermi resonance is a phenomenon of molecular vibrational coupling and energy transfer occurred between different groups of a single molecule or neighboring molecules. Many properties of Fermi resonance under different external fields, the investigation method of Raman spectroscopy as well as the application of Fermi resonance, etc need to be developed and extended further. In this article the research results and development about Fermi resonance obtained by Raman spectral technique were introduced systematically according to our work and the results by other researchers.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
February 2015
The ν1-ν18a Fermi resonance (FR) of phenol were investigated by pressure-dependent Raman spectroscopy from atmospheric up to P=15.2GPa and temperature-dependent Raman spectroscopy from 40 down to T=-180°C, respectively. In the case of pressure, we found the Fermi coupling coefficient W, which were calculated based on the FR theory, exposed a value turnover between 1.
View Article and Find Full Text PDFBackground: Nonalcoholic steatohepatitis (NASH), the advanced stage of nonalcoholic fatty liver disease that is characterized by both steatosis and severe injury in liver, still lacks efficient treatment. The traditional Chinese formula Salvia-Nelumbinis naturalis (SNN) is effectively applied to improve the symptoms of nonalcoholic simple fatty liver (NAFL) patients. Previous studies have confirmed that SNN could reduce the liver lipid deposition and serum transaminases of NAFL experimental models.
View Article and Find Full Text PDFRaman spectra of ice VII and X were investigated using strong plasma shockwave generated by laser-induced breakdown (LIB) in liquid water. Simultaneously, the occurrence of the hydrogen emission lines of 656 nm (Hα), 486 nm (Hβ), 434 nm (Hγ) and 410 nm (Hδ) was observed. At 5 × 10(12) W/cm(2) optical power density, the O-H symmetric stretching, translational and librational modes of ice VII and a single peak at 785 cm(-1) appeared in the spectra.
View Article and Find Full Text PDFLingguizhugan decoction (LGZG), a classic traditional Chinese medicine (TCM) formula, has been used to treat obesity and hyperlipidemia in recent years, but the related mechanisms underlying the regulation of lipid metabolism by LGZG are not clear yet. Here, we reported the effectiveness and possible mechanisms of LGZG on rats with fatty liver disease induced by high-fat diet (HFD). Our results demonstrated that LGZG significantly attenuated HFD-induced fatty liver disease, as measured by body weight, liver index, epididymal fat pad-body weight ratio (EFP/BW), liver injury, and hepatic triglycerides (TG) probably through increasing serum thyroid hormone levels, improving beta-oxidation (via modulation of TR β 1 and CPT1A expression), metabolism and transport (through modulation of SREBP-1c, ACSL and ApoB100 expression) of fatty acid.
View Article and Find Full Text PDFStimulated Raman scattering (SRS) of sulfur-II (S-II) phase was investigated by laser decomposition of liquid carbon disulfide. As a matter of fact, above a threshold of the laser intensity, it is suggested that a strong shock wave is generated in the liquid carbon disulfide, which is decomposed owing to the induced high dynamic pressure and temperature. One bending mode E frequency at 289 cm(-1) and one symmetric stretching mode A1 frequency at 490 cm(-1) of S-II phase were observed.
View Article and Find Full Text PDFZhong Xi Yi Jie He Xue Bao
October 2012
Objective: To explore the pathogenesis of nonalcoholic fatty liver (NAFL) in traditional Chinese medicine (TCM) by comparing the therapeutic efficacy of methods for fortifying the spleen and replenishing qi, warming yang and fortifying the spleen and warming yang to move water.
Methods: Male Wistar rats were randomly divided into normal, model, Sijunzi Tang (SJZ), Lizhong Tang (LZ), Linggui Zhugan Tang (LGZG) and Shenzhuo Tang (SZ) groups. Rats in the normal group were fed with ordinary diet, while the rats in the other groups were fed with high fat diet including 88% ordinary food, 10% lard oil and 2% cholesterol.
Spectrochim Acta A Mol Biomol Spectrosc
October 2012
We have measured the Raman spectra of liquid CS(2) at different volume concentrations in CHCl(3) and CH(2)Cl(2) solutions. With decreasing the volume concentration of CS(2), a noticeable growth in the 2ν(2) band frequency was observed, while the ν(1) band location remained practically unchanged. This asymmetric wavenumber shift phenomenon of the Fermi doublet ν(1) and 2ν(2) of CS(2) has been ascribed to weak, non-conventional hydrogen bonds formed between the CS(2) and the solvent molecules.
View Article and Find Full Text PDFObjective: To test whether nonalcoholic hepatic steatosis sensitizes carbon tetrachloride (CCl4)-induced liver injury, and to assess the therapeutic effect of Chinese medicine extracts of Dangfei Liganning capsules and their potential underlying mechanisms.
Methods: Male Wistar rats were fed a high-fat diet to induce nonalcoholic fatty liver disease (NAFLD) or a normal diet (N). Eight weeks later, a nonlethal dose of CCl4 was applied intraperitoneally.
Objective: To study the mechanism of liver injury induced by carbon tetrachloride (CCl(4)) in rats with non-alcoholic fatty liver disease (NAFLD), and the therapeutic effects of the extract mixture of Dangyao (Swertia pseudochinensis Hara) and Shuifeiji (Silybum marianum Gaertn) on NAFLD rats with liver injury.
Methods: Male Wistar rats were randomized into normal control group, CCl(4) group, high-fat diet group, high-fat diet plus CCl(4) injection group (model group), diammonium glycyrrhizinate group and extract mixture group. Except the normal control and CCl(4) groups, rats were fed with high-fat diet (88% normal chow, 10% lard and 2% cholesterol) to induce NAFLD.
Spectrochim Acta A Mol Biomol Spectrosc
April 2012
The effect of the Fermi resonance (FR) on the Raman scattering cross sections (RSCSs) of the Fermi doublet ν1, 2ν2 of liquid CS2 in C6H6 using the method of changing the volume concentration of the solution is investigated. We have calculated the RSCSs of the Fermi doublet ν1, 2ν2 using Onsager's theory with the 992 cm(-1) Raman line of C6H6 as the internal standard. The result shows that the RSCS of the ν1 line decreases with decreasing the volume concentration of CS2, while that of the 2ν2 line unexpectedly increases.
View Article and Find Full Text PDFObjective: To study the effects of Jiangzhi Granule (JZG), a compound traditional Chinese herbal medicine, in regulating liver X receptor α (LXRα) and sterol regulatory element-binding protein-1c (SREBP-1c) expressions in a rat model of non-alcoholic fatty liver disease (NAFLD).
Methods: Forty specific pathogen-free Wistar male rats were randomly divided into normal group, untreated group, pioglitazone (PIO) group and JZG group. All rats were fed with high-fat diet (88% normal chow plus 10% lard plus 2% cholesterol) for 4 weeks except for the normal group.