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1.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(7): 1762-6, 2011 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-21942019

RESUMO

All-reflection Fourier transform imaging spectrometer (ARFTIS) is a novel imaging spectrometer. The specialty is not only high spectrum resolution, but also wide band and non-chromatism. It is good for remote sensing field of wide band imaging. Single spectrum calibration, average calibration and weighted average calibration are three common calibration methods. However, they all are limited. Because they cannot meet the demand on both convenience and high precision. In the present paper, the authors propose a novel model for spectrum calibration. It can work in high precision with single spectrum calibration. At the same time, the method is steady, and the average error is less than 5% with multi-bands calibration. It provides a convenient way for the non-professional calibration situation and outer simply calibration work.

2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(11): 3149-53, 2011 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-22242537

RESUMO

During the spectral imaging course of interference imaging spectrometers, satellite platform's instability will bring serious impact on the imaging quality. Based on studying the degradation mechanism, a differential dynamic imaging simulation method is proposed here to simulate the process of spectral imaging degradation. And in this method, the mean ratio of doping is put forward, which combines the satellite motion parameters with the impacts on spectral imaging. And the quantitative relationship between them is deduced in detail With environmental resources satellite as an example, the degraded result is simulated, showing that the vibration affects the spectral imaging not only in the spatial resolution but also in spectrum, with the region of rich species having more serious influence. And through the simulation and analysis, the satellite attitudes' stability is requested accurately, below which the impacts of satellite vibration on spectral imaging should be significant and it's necessary to adopt corresponding compensation measures.

3.
J Chem Phys ; 127(17): 175102, 2007 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-17994852

RESUMO

The nature of interactions of furan with various hydrides (Y) (Y=HF,HCl,H2O,H2S,NH3,PH3) is investigated using ab initio calculations. The contribution of attractive (electrostatic, inductive, and dispersive) and repulsive (exchange) components to the interactions energy is analyzed. HF, H2O, and NH3 favor sigma o-type H bonding, while HCl, H2S, and PH3 favor pi-type H bonding. Interaction energy decomposition reveals that sigma o-type complexes interactions are predominantly electrostatic in nature, while the dispersion and electrostatic interactions dominate the pi-type complexes.

4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(5): 850-3, 2007 May.
Artigo em Chinês | MEDLINE | ID: mdl-17655087

RESUMO

The new complex Tb0.5 Eu0.5 (TTA)3Dipy was synthesized. By doping polymer PVK with Tb0.5 Eu0.5 (TTA)3Dipy, the EL device was fabricated with the structure of ITO/PVK: Tb0.5 Eu0.5 (TTA)3Dipy/PBD/Al using PVK: Tb0.5 Eu0.5 (TTA)3Dipy as the emitting layer. Compared with the blend PVK: Eu(TTA)3, the Tb3+ acts as an energy transfer bridge, which enhances the energy transfer efficiency between PVK and Tb0.5 Eu0.5 (TTA)3Dipy. As a result, the emission of Eu3+ is enhanced with the quenching of the emission of PVK. The process of energy transfer was studied.


Assuntos
Compostos Organometálicos/análise , Espectrometria de Fluorescência/métodos , Transferência de Energia , Európio , Estrutura Molecular , Térbio
5.
J Chem Phys ; 126(14): 144301, 2007 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-17444706

RESUMO

Using ab initio calculations, the authors' predicted for the first time that the halogen-bonded complex FBrdelta+...delta+BrF and hydrogen-bonded complex FBrdelta+...delta+HF formed by the interactions between two positively charged atoms of different polar molecules can be stable in gas phase. It shows that halogen bond or hydrogen bond not only exists between oppositely charged atoms but also between like-charged atoms. That the attraction arising from the special halogen bond or hydrogen bond can exceed the electrostatic repulsion between two contact positively charged atoms stabilizes the complex. Of course, from the point of view of physics they can consider the interactions in FBrdelta+...delta+BrF and FBrdelta+...delta+HF as mainly the sum of the long range molecular interactions, namely, electrostatic, induction, and dispersion with some short-range repulsion. They found that the intermolecular electron correlation contribution representing dispersion interaction plays a crucial role in the stabilities of seemingly repulsive complexes FBrdelta+...delta+BrF and FBrdelta+...delta+HF.


Assuntos
Halogênios/química , Modelos Químicos , Modelos Moleculares , Sítios de Ligação , Simulação por Computador , Transferência de Energia , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Eletricidade Estática
6.
J Chem Phys ; 126(13): 134301, 2007 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-17430026

RESUMO

Equilibrium geometries, interaction energies, atomic charge, and charge transfer for the intermolecular interactions between furan and dihalogen molecules XY(X; Y=F,Cl,Br) were studied at the MP2aug-cc-pVDZ level. Three types of geometry are observed in these interactions: the pi-type geometry (I), in which the XY lies above the furan ring and almost perpendicularly to the C4-C5 bond of furan; the sigma-type geometry (II), where the X atom is pointed toward the nonbonding electron pair (n pair) of oxygen atom in furan; and the chi-type geometry (III), describing a blueshift hydrogen bond formed between the hydrogen atom of furan and dihalogen molecules XY. The calculated interaction energies show that the pi-type structures are more stable than the corresponding sigma-type and chi-type structures. To study the nature of the intermolecular interactions, an energy decomposition analysis was carried out and the results indicate that both the pi-type and sigma-type interactions are dominantly inductive energy in nature, while dispersion energy governs the chi-type interactions.

7.
J Colloid Interface Sci ; 307(1): 94-100, 2007 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17188288

RESUMO

A novel cetyltrimethyl ammonium silver bromide (CTASB) complex has been prepared simply through the reaction of silver nitrate with cetyltrimethyl ammonium bromide (CTAB) in aqueous solution at room temperature by controlling the concentration of CTAB and the molar ratio of CTAB to silver nitrate in the reaction solution, in which halogen in CTAB is used as surfactant counterion. The structure and thermal behavior of cetyltrimethyl ammonium silver bromide have been investigated by using X-ray diffraction (XRD), infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), UV/vis spectroscopy, thermal analysis (TG-DTA), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The results show that the complex possesses a metastable layered structure. Upon heating the CTASB aqueous dispersion to above 80 degrees C, the structure change of the complex took place and CTAB-capped nanosized silver bromide particles further formed.

8.
J Chem Phys ; 125(17): 174716, 2006 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-17100470

RESUMO

Noise-assistant transduction was investigated in coupled polymer chains where one subsystem was exposed to environment noise. It was found that coupling could transfer oscillation from one subsystem disturbed by noise to the other not disturbed by noise and play a role of a noise filtering for the other. Then, a sort of coupling-induced synchronization was investigated as a function of noise intensity and coupling strength. In particular, we calculated the minimum coupling strength to reach synchronization and pointed out that noise dominated at small coupling strength, otherwise, coupling dominated.

9.
J Environ Sci (China) ; 17(2): 350-2, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16295920

RESUMO

A series of TiO2-MoO3 nano-composite photocatalysts were prepared by supercritical fluid dry method (SCFD) and an impregnation technique with TiCl4 and (NH4)6Mo7O24.4H2O as the starting materials. The catalysts were characterized by the means of XRD, TEM and UV-Vis. Methyl orange was used as model compound for the evaluation of their catalytic activities. The results indicated that the photo-catalyst prepared by SCFD had the advantages of small size (12.84 nm), narrow distribution and good dispersivity. The presence of small amount of Mo in composite catalyst gives rise to the red shift of its absorbance wavelength, decrease of its energy gap and increase of the utility of visible light. Furthermore, higher surface acidity of the photo-catalyst was obtained as the result of the addition of MoO3. Compared with pure TiO2, the catalytic activity of the TiO2-MoO3 nano-composite photo-catalyst was improved significantly. As the doping concentration of the composite catalysts was controlled at 0.6% (molar percentage), 100% degradation of methyl orange was achieved with in 1.2 h irradiation time.


Assuntos
Poluição Ambiental/prevenção & controle , Molibdênio/química , Nanoestruturas/química , Nanotecnologia/métodos , Titânio/química , Compostos Azo/química , Catálise , Cinética , Microscopia Eletrônica de Transmissão , Nanoestruturas/ultraestrutura , Nanotecnologia/instrumentação , Fotólise , Espectrofotometria Ultravioleta
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