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1.
Acta Radiol ; 64(8): 2446-2454, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37551019

RESUMO

BACKGROUND: The optimal treatment for some symptomatic, benign osteopathy lesions is yet to be identified. PURPOSE: To investigate the clinical efficiency of cementoplasty in managing symptomatic, benign osteopathy. MATERIAL AND METHODS: Between June 2006 and January 2020, we retrospectively enrolled 31 patients (10 men, 21 women; mean age = 46.5 ± 16.6 years; age range = 20-85 years), accounting for 34 treatment sites, who underwent percutaneous osteoplasty (14 treatment sites) and percutaneous vertebroplasty (20 treatment sites) with digital subtraction angiography (DSA) or DSA combined with computed tomography (CT). All the participants experienced different degrees of clinical symptoms with benign osteopathy lesions. The technical success of the procedure and occurrence of complications were recorded. Follow-up examinations were conducted to assess the treatment outcome using the MacNab criteria. RESULTS: All the participants had a diagnosis of benign osteopathy lesions before or after the cementoplasty. Surgery was successfully completed in all patients. Cement distributions were diffuse and homogeneous, with the complication of cement leakage occurring in 17.6% (6 of 34) of the lesions. The leakage occurred in the intervertebral disc (n = 1), the intra-articular space (n = 1), and the surrounding soft tissue (n = 4). Analysis of the treatment outcome using the MacNab criteria revealed that all patients showed improvement in their clinical symptoms to some extent and in the quality of life. CONCLUSION: Cementoplasty is an effective treatment for symptomatic, benign osteopathy, with the advantage of favorable clinical outcomes, and low complication rate.


Assuntos
Doenças Ósseas , Cementoplastia , Masculino , Humanos , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Estudos Retrospectivos , Qualidade de Vida , Cementoplastia/métodos , Cimentos Ósseos/uso terapêutico , Resultado do Tratamento
2.
Neural Regen Res ; 14(1): 107-113, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30531084

RESUMO

Many clinical studies have addressed the treatment of acute cerebral hemorrhage using acupuncture. However, few studies have examined the relationship between time of acupuncture and curative effect on cerebral hemorrhage. By observing the effect of acupuncture on changes in histopathology, ultrastructure, and neuroethology in a cerebral hemorrhage model of rats, we have directly examined the time-effect relationship of acupuncture. The rat model of cerebral hemorrhage was produced by slowly injecting autologous blood to the right caudate nucleus. The experimental groups were: 3-, 9-, 24-, and 48-hour model groups; and 3-, 9-, 24-, and 48-hour acupuncture groups. The sham-operation group was used for comparison. Acupuncture was performed at the Neiguan (PC6) and Renzhong (DU26) acupoints, twice a day, 6 hours apart, for 5 consecutive days. Brain tissue changes were observed by light microscopy and transmission electron microscopy. Neuroethology was assessed using Bederson and Longa scores. Our results show that compared with the sham-operation and model groups, Bederson and Longa scores were lower in each acupuncture group, with visibly improved histopathology and brain tissue ultrastructure. Further, the results were better in the 3- and 9-hour acupuncture groups than the 24- and 48-hour acupuncture groups. Our findings show that acupuncture treatment can relieve pathological and ultrastructural deterioration and neurological impairment caused by the acute phase of cerebral hemorrhage, and may protect brain tissue during this period. In addition, earlier acupuncture intervention following cerebral hemorrhage (by 3 or 9 hours) is associated with a better treatment outcome.

3.
Oncol Res ; 24(5): 371-380, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27712594

RESUMO

MicroRNA-21 (miRNA-21), a kind of short, noncoding RNAs, functioned as a tumor marker and was upregulated in renal cell carcinoma (RCC). However, the underlying mechanisms of miRNA-21 in RCC were uncertain. Therefore, the effects and mechanisms of miRNA-21 on the proliferation, differentiation, and apoptosis of cultured human RCC cells were further investigated in this study. After slicing miRNA-21 in RCC cells, the viability, mRNA expression of C/EBPα and PPARγ, caspase 3 activity, and protein expression of mTOR, STAT3, and pSTAT3 were determined. It was found that knockdown of miRNA-21 downregulated the optical density (OD) value of cells, inhibited mRNA expression of PPARγ and C/EBPα, and enhanced activity of caspase 3. Furthermore, protein expression of pSTAT3 was also decreased in the absence of miRNA-21. Notably, miRNA-21-changed proliferation, differentiation, and apoptosis of human RCC cells were partially regulated following the block of the mTOR-STAT3 signaling pathway by the mTOR inhibitor (XL388). It was indicated that miRNA-21 promoted proliferation and differentiation and decreased apoptosis of human RCC cells through the activation of the mTOR-STAT3 signaling pathway.


Assuntos
MicroRNAs/metabolismo , Fator de Transcrição STAT3/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Apoptose/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Diferenciação Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , MicroRNAs/biossíntese , MicroRNAs/genética , Fator de Transcrição STAT3/genética , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Transfecção
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(1): 6-10, 2016 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-27228730

RESUMO

All-trans-ß-carotene has important functions of light collection and light protection, and it is also an important electrooptical material. The Raman spectra of polyenes are a result of the modulation effect of the π electron energy gap on the vibration of CC bonds, which associate with the external field. So it has higher theoretical significance and practical value to study the molecular structure and properties change under the external field. Ultraviolet-visible absorption spectra and resonant Raman spectra of all-trans-ß-carotene in cyclohexanol were measured from 341 to 275 K. The liquid-solid phase transition of the sample appears at 295 K. The characteristic energy describes the conformational change of all-trans-ß-carotene molecule. After the solution phase transition, the characteristic energy ε of all-trans-ß-carotene molecule becomes bigger. And when temperature decreasing, the rate of change of the Huang-Rhys, the wavelength of UV absorption peak, electron-phonon Parameter, RSCSs of the CC bond increase. the Huang-Rhys in solid phase is an order of magnitude higher then liquid phase. The characteristic energy of liquid is 0.206 7 eV. The characteristic energy of liquid is 0.559 6 eV. The increasing of the characteristic energy ε makes the rate of increasing of the effectively conjugated length becomes bigger. The decreasing of the π electric energy gap quickens. The function of moderation from electron energy gap to all-trans-ß-carotene molecule enhances. Electron-phonon Parameter increases. RSCSs of the CC bond substantially increases.


Assuntos
Transição de Fase , beta Caroteno/química , Luz , Polienos/química
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(11): 3455-60, 2016 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-30198241

RESUMO

The Visible absorption and Raman spectra of ß-carotene were measured in dimethyl sulfoxide in temperature ranging from 81 to 25 ℃ and in carbon disulfide in pressure range from 0.04 to 0.60 GPa, respectively. The results indicated that the visible absorption and Raman spectra are both red-shifted, Raman scattering cross section increase with the temperature decreasing. And with the pressure increasing, the visible absorption spectra are red-shifted, but the frequency shift towards higher frequencies in the Raman spectra, the Raman scattering cross section decrease unexpectedly. The latter can't be explained by the model of "effective conjugation length" and "coherent weakly damped electron-lattice vibrations". In this paper, we combined electron-vibration coupling rule with theoretical calculations and found that the electron-phonon coupling constant had a certain changing trend with the temperature and pressure variation, which Indicate that the interaction between π-electron and CC bond vibration was essential for this experiment result. Thus, the turning effect of energy gap of the π on CC vibration mode is responsible for such phenomenon.

6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(3): 635-9, 2015 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-26117870

RESUMO

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. Especially, the results of the behaviors of intramolecular and intermolecular Fermi resonance of some molecules under some external fields such as molecular field, pressure field and temperature field, etc were investigated and demonstrated in detail according to the Raman spectra obtained by high pressure DAC technique, temperature variation technique as well as the methods we planed originally in our group such as solution concentration variation method and LCOF resonance Raman spectroscopic technique, and some novel properties of Fermi resonance were found firstly. Concretely, (1) Under molecular field. a. The Raman spectra of C5H5 N in CH3 OH and H2O indicates that solvent effect can influence Fermi resonance distinctly; b. The phenomena of the asymmetric movement of the Fermi resonance doublets as well as the fundamental involved is tuned by the Fermi resonance which had not been found by other methods were found firstly by our variation solution concentration method; c. The Fermi resonance properties can be influenced distinctly by the molecular group reorganization induced by the hydrogen bond and anti-hydrogen bond in solution; d. Fermi resonance can occurred between C7 H8 and m-C8H10, and the Fermi resonance properties behave quite differently with the solution concentration; (2) Under pressure field. a. The spectral lines shift towards high wavenumber with increasing pressure, and frequency difference Δ varies with pressure, which induced the change of W; b. The W of νi + ν4 ν3 of CCl4 in C6H6 decreased more quickly in solution than in pure liquid with increasing pressure and the Fermi resonance disappeared ahead of that in pure liquid, which indicates that the phenomenon of Fermi resonance induced by pressure effect can reveal the mechanism of some solvent effects. (3) Under temperature field. a. The Fermi resonance properties of different molecules behave quite differently with temperature. For an instance, the one of CO2 can be influenced distinctly by temperature, while the one of CS2 behaves no change with temperature. This article offers systematic theoretical and experimental support to the investigation of identification and assignment of molecular spectral line, the confirmation of molecular conformation and conformers, the effect of hydrogen bond on molecular structure and properties, etc.

7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(7): 1904-7, 2015 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-26717749

RESUMO

Beta-carotene is an important kind of polyene biomolecules, which has significant applications on researching optoelectronic and functional materials. In-situ high pressure Raman spectra of beta-carotene are measured in CS2 solution and water respectively at pressure range from 0-0.60 GPa. Then we compared both of them the Raman shift and CC bond of the full width at half maximum (FWHM) of the Raman spectra. It is therefore concluded that both of the samples' Raman shift moved to the high wave number and the full width at half maximum increased depending of the pressure. The experiment phenomena were interpreted by the theory of "coherent weakly damped electronic-lattice vibration model" and "effective conjugation length model". The mechanism is that the beta-carotene is compressed and has the lower structure order, shorte the effective conjugation length, decreased Raman active, weaker the coherent weakly damping CC bond vibration in high pressure. Because of the CC bond length become short, so the Raman spectra are found to blueshift. The CC bond of the full width at half maximum (FWHM) of the Raman spectra increased is attributed to the increase of difference in C--C and C==C bond lengths. Moreover, due to dissolving in non-polar CS2 solvent, the beta-carotene encounters the interaction of the surrounding solvent molecules. So the dispersion force interaction between solute and solvent is more sensitive to pressure. Then it makes that the slop of Raman shift and the full width at half maximum in the CS2 solution are faster than dissolved in water with increasing pressure. This paper provides an application value for research on molecular structure change under the external field and the presence form of polyenes biomolecules in the solvent.


Assuntos
Análise Espectral Raman , beta Caroteno/análise , Estrutura Molecular , Pressão , Soluções , Solventes , Água
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(5): 1275-8, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-25095421

RESUMO

The present paper summarizes the characteristics of resonance Raman spectra of the linear polymer molecule, and its relations with the molecular structure, including: electronic spectra(ultraviolet-visible absorption spectrum), Raman spectra characteristics and its relations with external field; Modulation relation between the electron energy gap and CC atom vibration; Several experimental results were obtained: The UV-visible absorption spectra are red-shifted with decreasing temperature, increasing solvent density and reducing solution concentration, and because the linear polymer molecule has high structured order, decreasing pi electron energy gap; extended pi electronic delocalization, large effective conjugation length, large intensity of the Raman activity, Ramrnan spectrum are red-shifted, with large scattering cross section. "Am plitude modes" are the ideal theory models to study the linear polymer molecule.

9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(5): 1302-5, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-25095427

RESUMO

The present paper cited that R Tubino and other people introduced a kind of electron-phonon coupling constants with dimension, which can establish the relation with the Huang-Rhys factor and calculate the electron-phonon coupling constants of every C-C bond vibration mode. There are many reports about the visible absorption and Raman spectra of all-trans-beta-carotene with pressure. But the study about the Raman scattering cross section and the Huang-Rhys factor with pressure have not been reported now. Visible absorption and Raman spectra of all-trans-beta-carotene were measured in carbon disulfide in the pressure range from 0. 04 to 0. 60 GPa. The results indicated that the visible absorption spectra of beta-carotene in nonpolar solvent carbon disulfide are red-shifted with pressure increasing, but the frequency shifts towards higher frequencies in the Raman spectra, the Raman scattering cross section decreases, Huang-Rhys factor increases, and the electron-phonon coupling constants of CC bond vibration modes increase. The mechanism is that all-trans-beta-carotene caused by compression and a decrease in the structurally ordered properties of the molecules leads to narrow energy gap of the pi, shortens effective conjugation length, hinders delocalization of pi-electron, decreases the Raman scattering cross section, and increases the Huang-Rhys factor and the electron-phonon coupling constants.


Assuntos
Fônons , beta Caroteno , Dissulfeto de Carbono , Elétrons , Pressão , Solventes , Análise Espectral Raman , Vibração
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(9): 2425-8, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24369645

RESUMO

In the present paper, DMSO/H2O mixture with the ratio of volume 1:1 was measured in the cooling process by Raman spectroscopy, and the Raman assignments was made to the DMSO molecular and water molecular. The results showed that the behavior between intra-molecular hydrogen bonds and inter-molecular hydrogen bonds of DMSO and water leads to the change in the Raman spectra of the S==O stretching vibration of DMSO and the O--H stretching vibration of water. Further analysis showed that the hydrogen bond between DMSO and water was enhanced in the course of temperature decreasing process (27 to -30 degrees C), and the intramolecular hydrogen bonds between water and water replaced the intermolecular hydrogen bonds of DMSO and water in the course of temperature decreasing process (-30 to -60 degrees C). The research provides experimental basis for hydrogen bonding theory in aqueous solution.

11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(9): 2429-32, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24369646

RESUMO

In the present paper, studies on in-situ Raman spectra at high pressure up to 12.85 Gpa were performed on beta-carotene using a diamond anvil cell (DAC), and the effects of pressure on the characteristic peaks and pi-electron delocalization of beta-carotene were discussed. The results showed that Raman frequencies of the main characteristic peaks of beta-carotene shifted to high wavenumber with the increase in pressure. The relation between pressure and the three main characteristic peaks of beta-carotene was given as follows: nu1, (C==C) = 4. 74P + 1511.4, w (C-C) = 2.55P + 157.6 and nu3 (CH3) = 2.25P + 1011.3. Under the pressure of 5.38 GPa, Raman spectrum of nu1 + nu2 sum frequency of beta-carotene was subjected to cleavage. Fuethermore, the degree of relectron decolization was reduced with the increase in pressure, leading to C==C double bond more compressible than C-C bond on the main chain of beta-carotene.


Assuntos
Análise Espectral Raman , beta Caroteno/química , Elétrons , Estrutura Molecular , Pressão
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(9): 2311-4, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24371847

RESUMO

A visible absorption and Raman spectra of all-trans-beta-beta-carotene was measured in cyclohexanol solution in the temperature range from 68 degrees C to 26 degrees C. The results indicated that the visible absorption spectra are red-shifted, Raman scattering cross section increases, Huang-Ryes factor and electron-phonon coupling constants of CC bond vibration modes decreases with the temperature decreasing. The changes are interpreted using the theory of "coherent weakly damped electronic-lattice vibration model" and "effective conjugation length model". The red shift of the absorption spectra and intensity of the Raman active are attributed to the thermal conformational change-induced increase in the effective conjugation length in all-trans-beta-carotene chains. All-trans-beta-carotene has strong coherent weakly damped CC bonds vibrational properties, which lead to large Raman scattering cross section in the solvent of low temperature. The electron-phonon coupling constants with dimension are used, which can easily establish relation with the Huang-Rhys factor and calculate the electron-phonon coupling constants of CC bond vibration modes. Effective conjugation length, the pi-electron delocalization range and the Raman scattering cross section are described by the electron-phonon coupling constants.


Assuntos
Análise Espectral Raman , Temperatura , beta Caroteno/análise , Elétrons , Solventes , Vibração
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(8): 2031-4, 2013 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-24159839

RESUMO

Stimulated Raman scattering was studied in water and heavy water using pulse laser at the wavelength of 532nm, not only obtaining the stimulated Raman of O-H and O-D stretching vibration, but also obtaining the stimulated Raman lattice vibration. When the laser energy was 130 mJ, the low frequency Stokes and anti-Stokes 313 cm(-1) line of water could be observed; When the laser energy was 160 mJ, the low frequnecy Stokes and anti-Stokes 280 cm(-1) line of heavy water could be observed. The results were explained by physics mechanism of laser induced plasma.

14.
Exp Clin Transplant ; 11(6): 482-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23745955

RESUMO

OBJECTIVES: We sought to develop a B-cell in vitro culture system and test B cells isolated from sensitized kidney recipients and healthy controls, and assess the effectiveness of proteasome inhibitors and mycophenolic acid on antibody secretion and cell apoptosis. MATERIALS AND METHODS: CD19(+) B cells and CD19(+)CD27(+) memory B-cell subsets were detected from peripheral blood mononuclear cells obtained from 6 MICA-sensitized kidney recipients and 6 healthy controls. Peripheral blood B cells were isolated and cultured with CpG2006, PMA, MICA antigen, B-cell activating factor, CD40 ligand (CD40L), human recombinant IL-2 (rhuIL-2), rhuIL-10, rhuIL-4, and rhuIL-21. After culturing for 7 days, we tested several variables of B-cell activity including differentiation, apoptosis, and IgM production. We also assessed the effects of 2 immunosuppressive drugs (mycophenolic acid and bortezomib) on antibody secretion and cellular apoptosis. RESULTS: Kidney recipients had a lower ratio of CD19+ B cells in peripheral blood mononuclear cells than did healthy controls. However, the percentage of CD19(+)CD27(+) B cells was higher in kidney recipients than in healthy controls. In the cell stimulation culture system, the ratio of CD19(+) B cells, CD19(+)CD27(+) B cells, and CD19(+)CD138(+) B cells increased after culturing for 7 days compared with unstimulated controls. In addition, the percentage of apoptotic B cells decreased, and antibody production increased in sensitized transplant patients and healthy controls. Treatment with bortezomib or mycophenolic acid induced B-cell apoptosis and inhibited secretion of antibodies. CONCLUSIONS: This study describes establishment of a B-cell in vitro culture system, showing that B cells may be stimulated to secrete antibodies. The study also provides an assay for studying B cells in vitro. This study provides information suggesting that bortezomib and mycophenolic acid can inhibit B-cell antibody secretion.


Assuntos
Linfócitos B/efeitos dos fármacos , Ácidos Borônicos/farmacologia , Antígenos de Histocompatibilidade Classe I/imunologia , Transplante de Rim , Ácido Micofenólico/farmacologia , Pirazinas/farmacologia , Idoso , Antígenos CD19/metabolismo , Apoptose/efeitos dos fármacos , Linfócitos B/imunologia , Linfócitos B/patologia , Bortezomib , Estudos de Casos e Controles , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Antígenos de Histocompatibilidade Classe I/sangue , Humanos , Imunoglobulina M/sangue , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Inibidores de Proteassoma/farmacologia
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(5): 1259-61, 2012 May.
Artigo em Chinês | MEDLINE | ID: mdl-22827067

RESUMO

Raman spectra of ice VII phase were obtained at room temperature when the pressure was from 2.5 to 23 GPa. The experimental results indicate that the oxygen atoms distance do-o of ice decreased with pressure increasing,which results in that hydrogen bond is shortened, O--H bond is lengthened,force constant is reduced, and Raman spectra are red shifted. The orientation order of proton (hydrogen atom) is first increased and then decreased with varying the pressure, which leads to the Raman intensity increasing and then decreasing, and Raman linewidth is decreased and then increased, and the linewidth is the least when the pressure is 13 GPa.

16.
Artigo em Inglês | MEDLINE | ID: mdl-22257719

RESUMO

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. With decreasing the volume concentration of CS2, two main effects of the solvent effect (SE) and the FR in binary solution that can make the ν1, 2ν2 RSCSs change: the SE, as calculated, reduces both the ν1 and 2ν2 RSCSs; the FR plays a significant role in reducing the ν1 RSCS and enhancing the 2ν2 RSCS. In comparison with our previous investigation [J. Raman Spectrosc. 41 (2010) 776-779], it was found that the stronger the FR is, the more the RSCS of the ν1 decreases and the 2ν2 increases. Thus, we proposed that the result can be best explained by taking into account the effect of the FR on the RSCSs of the Fermi doublet. In addition, this paper also gives an explanation to the experimental results deviating from the theoretical results of the scattering coefficients of CS2 in solvent C6H6 as mentioned in Fini's paper.


Assuntos
Benzeno/química , Dissulfeto de Carbono/química , Análise Espectral Raman/métodos , Solventes
17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(5): 1270-3, 2011 May.
Artigo em Chinês | MEDLINE | ID: mdl-21800580

RESUMO

The values of Raman scattering coefficients of some molecules in which Fermi resonance occurs vary with solution concentration variation. We measured the Raman spectra of some solvents such as CCl4, CS2, C6H6, etc by changing the concentration of the solutions ranging from 10% to 100% in volume. As a result, the authors obtained the general law of Fermi resonance. We found some weak Fermi resonance phenomena as well that the two bands of Raman spectrum shift asymmetrically and that the fundamental of overtone is tuned by Fermi resonance and moves towards the same direction with the overtone simultaneously, which is same as the results Bier K. D. obtained by means of high-pressure technique. By means of this method, the authors demonstrated the conclusion that only the fundamental in combinations which has the same symmetry as the fundamental involved in Fermi resonance directly can its intensity variation influence the Fermi resonance. In this article, the authors present a new method to study Fermi resonance. This method is valuable in the identification and the assignment of spectral lines of solutions, the determination of molecular configuration of enzyme, the discrimination of isomer, as well as the influences on the molecular structures and properties caused by hydrogen bond.

18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(8): 2141-5, 2010 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-20939325

RESUMO

The Raman spectra of binary solution (CCl4 and C6 H6) and pure liquid were measured up to pressures of 11 GPa. The results show that pressure effect on binary solution is different from that on pure liquid: When mixing two liquids, owing to the changes in the density of the solution, intermolecular distance decreases and interaction energy increases, the frequency shift (blue shift) of spectral bands increases, and the frequency shift of binary liquid is faster than pure liquid frequency shift. Phase transitions (spectral bands splitting) change earlier and natural frequency difference delta0 increases with increasing pressure, while the Fermi resonance bands nu1 + nu6 and nu8 of benzene and nu1 + nu4 and nu3 of CCl4 disappear as the pressure decreases gradually, the spectral bands with different compressibility have different speed, whereas CCl4 has smaller density, longer bond, smaller force constant and larger compressibility and is easy to compress, C6H6 has larger density, smaller bond, larger force constant, smaller compressibility and is hard to compress. The frequency shift of CCl4 is faster than benzene. In this paper we provide good reference on Raman bands assignment and certification under high pressure, and also provide methods and ideas for study of the different environment of high pressure effect, intermolecular interaction and solvent effect.

19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(3): 688-91, 2010 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-20496688

RESUMO

The Raman scattering coefficients of the fundamental v1 (992 cm(-1)) of C6 H6 and the fundamental v1 (656 cm(-1) ) of CS2 changed dramatically with relative concentration of the binary solution of CS2 and C6 H6. The Raman spectra of the binary solution with different relative concentrations were measured. The results show that both the v1 fundamentals intensities changed dramatically with the relative concentration of the solution and the fundamental v1 of C6 H6 has little effect on the Fermi resonance v1 +v6-v8. On the contrary, the change in the v1 fundamental intensity of the CS2 changed which has more effect not only on the Fermi resonance v1 - 2v2 but also on the v2 fundamental. In this report, the experimental results were analyzed based on the J. F. Bertran theory and group theory.

20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(1): 6-8, 2010 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-20302068

RESUMO

Raman spectra of liquid carbon disulfide (CS) and carbon tetrachloride (CCl4) were measured. And the spectral intensity was analyzed using the J. F. Bertran theory and the group theory. The rule about Fermi resonance was obtained from the Raman spectra of carbon disulfide (CS) and carbon tetrachloride (CCL4): (1) The energy can transfer between a fundamental and an overtone frequency about Fermi resonance; the two spectra have the same intensity. The spectral intensity of the two spectra was equal (R=1) about Fermi resonance, when the difference between fundamental of Fermi resonance and overtone of Fermi resonance was very small. (2) The intensity of overtone is stronger than that of fundamental's. (3) The spectrum of Fermi resonance was observed, but the fundamental frequency was not. This article has very good reference value for the assignments in the molecular structure and the research of contents.

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