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1.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(7): 2054-9, 2015 Jul.
Artigo em Zh | MEDLINE | ID: mdl-26717778

RESUMO

Fourier transform infrared spectrometer can be realized in high temperature flue gas multicomponent measurement at the same time, has wide application prospects in the field. And one of the important factors to determine the success of application, lies in the measuring system of infrared interference figure sampling phase error control. This paper discusses the main-reasons of the appearance of phase error in the system, through the analysis of Helium-neon laser interference signal zero uniformity, illustrates the produce phase error is the main reason of the laser signal and reference signal phase difference. At the meantime, the quantitative analysis of the phase error influence on instrument signal to noise ratio (SNR), also the Mertz phase correction method for the instrument improves the thousands of times of the original signal to noise ratio. And the related experiment, the experimental results show that the system based on the interference figure sampling method satisfy the needs of high temperature flue gas measurements.

2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(11): 3214-9, 2015 Nov.
Artigo em Zh | MEDLINE | ID: mdl-26978939

RESUMO

The four kinds of the structure characteristics of rotary type interferometer are mainly analyzed from the classical Michelson interferometer structure in the paper. The Optical path difference between the interferometer and the rotation angle is also analyzed. By setting parameters, the four kinds of rotary type optical path difference of the interferometer are simulated based on the optical path difference formula. The rotation velcocity of the four kinds of interferometers is also simulated. By simulation and contrast of the optical path difference, the relationship is intuitively reflect by figure between the optical path difference and the rotation angle. The scope of the rotation angle is discussed within 3% of the velocity errors. It is the very good reference significance to study the structure and properties of the interferometer by analyzing and simulating the optical path difference discussed in the paper.

3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(7): 1771-4, 2013 Jul.
Artigo em Zh | MEDLINE | ID: mdl-24059172

RESUMO

In the present paper, the infrared spectrum of aerosol and NH4 NO3 was analysed and compared, and the result showed that the infrared spectral features of aerosol are consistent with that of NH4 NO3. The absorption coefficient alpha and the mass absorption cross section kappa of NO3- was calculated by the transmissivity of NO3- in NH4 NO3 according to Beer-Lambert law. Then the imaginary part of the complex refractive index was calculated through alpha. The real part of the complex refractive index was derived from the K-K(Kramers-Kroning) relationship. It has important significance for further research on the scattering and absorption characteristics of the different composition of the atmospheric aerosol through analysing the results of the experiment.

4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(12): 3193-6, 2012 Dec.
Artigo em Zh | MEDLINE | ID: mdl-23427533

RESUMO

The authors measured IR transmission spectra of two different concentrations of Bacillus subtilis spores by using Fourier transform infrared spectroscopy (FTIR) technology. The mass extinction cross section k of Bacillus subtilis spores was calculated according to Lambert-Beer law and the imaginary part n(i) of the complex refractive index was also calculated through k. The real part n(r) of the complex refractive index was derived from the KK (Kramers-Kronig) relationship and the experimental results were also analyzed and discussed with the study of measurement and analysis method of the complex refractive index on Bacillus subtilis spores, it is of great significance to further research the absorption and scattering characteristics, and to broaden the measurement and remote sensing technology method of the biological aerosols.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Bacillus subtilis/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Bacillus subtilis/classificação , Bacillus subtilis/fisiologia , Esporos Bacterianos/classificação , Esporos Bacterianos/isolamento & purificação
5.
Metab Brain Dis ; 17(4): 359-66, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12602512

RESUMO

Juvenile visceral steatosis (JVS) mouse is an animal model of human primary carnitine deficiency caused by a mutation of the gene encoding carnitine transporter, and suffers from various symptoms, such as fatty liver, growth retardation, hyperammonemia, hypoglycemia, and cardiac hypertrophy. We have shown that hyperammonemia during the weaning period (15-26 days of age) is caused by suppression of urea cycle enzyme gene expression. The suppression resulted from activation of a transcription factor, AP-1. We have found that a cis-element for AP-1 binding is present in the enhancer region of the carbamoylphosphate synthetase (CPS) gene, and that the AP-1 binding site is involved in the suppression of CPS induction by dexamethasone in cultured hepatocytes and in the suppression of CPS expression in the liver of JVS mice. The blood ammonia levels in JVS mice increased during the weaning period, and then decreased to almost control levels after 30 days of age. In this paper, we report that in adult JVS mice, ammonia levels again increased after starvation for at least 24 hr and this effect was suppressed by carnitine treatment. Starvation for 48 hr did not significantly suppress CPS activity in the liver and did not cause any change in hepatic ornithine concentration. The concentration of N-acetylglutamate in the liver of starved JVS mice was not significantly different from that of JVS mice treated with carnitine. These results indicate that the hyperammonemia in carnitine-deficient adult JVS mice during starvation and the suppression by carnitine treatment differ from those found during the weaning period, and thus the cause of hyperammonemia and the mechanism of suppression remain to be solved.


Assuntos
Carnitina/deficiência , Hiperamonemia/etiologia , Inanição/complicações , Envelhecimento/sangue , Aminoácidos/metabolismo , Amônia/sangue , Animais , Animais Recém-Nascidos/sangue , Animais Recém-Nascidos/crescimento & desenvolvimento , Carbamoil-Fosfato Sintase (Amônia)/metabolismo , Carnitina/farmacologia , Glutamatos/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Mutantes , Inanição/metabolismo , Fatores de Tempo , Ureia/metabolismo
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