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1.
Huan Jing Ke Xue ; 35(3): 1009-15, 2014 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-24881390

RESUMO

The effects of biosurfactant alkyl polyglycosides (APG) on the hydrolysis and acidification of waste activited sludge including dosage of APG and hydrolysis time were investigated. It was found that APG reduced the tension of sludge hydrolysate, promoting sludge hydrolysis. The concentrations of SCOD, protein and soluble carbonhydrate reached the maximum within 12 h at the optimal dosage of 0.2 g x g(-1) TSS, rising from 4 280.2, 1 122.9 and 246.5 mg x L(-1) to 6481.1, 1 639.3 and 1205.8 mg x L(-1), respectively, and the short-chain fatty acids (SCFAs) concentration increased from 1309.9 mg x L(-1) to 2221.6 mg x L(-1) simultaneously, the percentage of individual SCFA changed as well, and the time required to reach the maximal SCFAs concentration will be prolonged with the increase of dosage. With increasing APG dosage, a-glucosidase relative enzyme activities increased from 1.5 to 2.5, while protease relative enzyme activity increased from 1.4 to 1.9 at low dosages and decreased to 1.5 at high dosages. Regardless of the biosurfactant APG, alpha-glucosidase and protease enzyme activities decreased along with the hydrolysis time. The pH showed a tendency of first decreasing and then increasing.


Assuntos
Ácidos Graxos Voláteis/química , Glicosídeos/química , Esgotos/química , Concentração de Íons de Hidrogênio , Hidrólise
2.
Zhonghua Yu Fang Yi Xue Za Zhi ; 46(6): 527-32, 2012 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-22943900

RESUMO

OBJECTIVE: To explore the correlation between single nucleotide polymorphisms (SNPs) of interleukin-28B (IL-28B) gene and the susceptibility to primary hepatocellular carcinoma (HCC). METHODS: A total of 300 histologically confirmed HCC cases (from November 2001 to April 2010) and 310 healthy controls with no history of chronic hepatitis B or hepatocellular carcinoma (2009-2010) were selected from a hospital in Guilin and a hospital in Beijing for this case-control study.139 HCC patients in the case group had complete clinical tracking data. All the subjects were Han Chinese, with no age or gender restrictions.2 ml peripheral blood samples were drawn from each subject with informed consent. SNP of rs12972991, rs4803223, rs8099917 and rs12979860 four loci in IL-28B gene were analyzed by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF). RESULTS: The frequencies of C allele at rs12972991, G allele at rs8099917 and G allele at rs4803223 were 6.7% (40/598), 7.9% (47/598) and 10.0% (59/588) respectively in case group; all higher than the corresponding frequencies in control group, separately 2.9% (18/618), 4.1% (25/616) and 3.6% (21/608). The differences were statistically significant (χ2=9.542, 7.858, 20.736, P values all<0.05). The above alleles could increase the risk of HCC, and the OR (95%CI) values were separately 1.67 (1.13-2.46), 1.49 (1.08-2.06) and 2.91 (1.79-4.72). The genotype frequencies of AC+CC at rs12972991, GT+GG at rs8099917, GA+GG at rs4803223 were 13.0% (39/299), 14.7% (44/299) and 19.0% (56/296) respectively in case group; while the frequencies were lower in control group, separately 5.8% (18/309), 8.1% (25/308) and 6.6% (20/304). The differences were statistically significant (χ2=9.319, 6.557, 20.948, P values all<0.05). These genotypes may increase the risk of HCC, and the adjusted OR (95%CI) values were 2.24 (1.31-3.83), 1.81 (1.14-2.88) and 2.90 (1.78-4.70), respectively. The stratified analysis of the clinical data indicated that the frequency of genotype GA+GG at rs4803223 was 50.0% (13/26) in patients of tumor thrombosis in portal vein (TTPV), higher than the frequency of genotype AA (21.1%, 23/109). The difference was statistically significant (χ2=8.965, P=0.003). CONCLUSION: The results suggested that IL-28B gene polymorphisms was correlated to the susceptibility to HCC in Chinese Han ethnic population. Among them, GA + GG genotype at rs4803223 could increase the risk of TTPV in HCC patients.


Assuntos
Carcinoma Hepatocelular/genética , Interleucinas/genética , Neoplasias Hepáticas/genética , Polimorfismo de Nucleotídeo Único , Alelos , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Interferons , Masculino , Pessoa de Meia-Idade
3.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 7): o1602, 2009 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-21582876

RESUMO

The title compound, C(14)H(11)NO(2)S(2), was synthesized by reaction of 2-(1,3-dithio-lan-2-yl-idene)-3-oxo-N-phenyl-butanamide with N,N'-dimethyl-formamide dimethyl acetal in N,N'-dimethyl-formamide. The mol-ecule exhibits a V-shaped conformation in the crystal, with a dihedral angle of 65.9 (2)° between the benzene and pyridine rings. In the crystal. C-H⋯O and C-H⋯S interactions are observed. Two C atoms of the dithiolane ring are disordered with occupancies in the ratio 0.541 (13)/0.459 (13).

4.
J Hazard Mater ; 155(1-2): 58-64, 2008 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-18166267

RESUMO

Synthesis of pure-form zeolite A were investigated using four concentrations of NaOH solution to dissolve Si source form fly ash, and with the addition of Al source, to prepare initial gel. Experimental results demonstrated, for two-stage method, that NaOH concentrations in initial gel played an important role in synthesis of pure-form zeolite A using fly ash as raw materials. Generally, pure-form zeolite A could be synthesized when following conditions were used: NaOH concentrations, 1.67, 5 and 6.67 M; the synthesis temperature, 100 degrees C; the corresponding crystallization time, 340, 250 and 190 min. However, a mixture phases of zeolites A and X were obtained at the condition of 3.33 M NaOH solution during various crystallization times. It was found that the higher NaOH concentration was used, the shorter crystallization time of zeolite A was required and the narrower particle size distribution of zeolite A was achieved. In addition, zeolite A submicron-crystals were first synthesized from fly ash using two-stage method in our study.


Assuntos
Carbono/química , Conservação dos Recursos Naturais/métodos , Material Particulado/química , Hidróxido de Sódio/química , Gerenciamento de Resíduos/métodos , Zeolitas/química , Cinza de Carvão , Cristalização , Resíduos Industriais , Tamanho da Partícula
5.
J Hazard Mater ; 151(2-3): 306-15, 2008 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17662522

RESUMO

Bactericide wastewater (BIW) contains isothiazolin-ones, high salinity, toxicity and non-biodegradable organic concentrations. In order to enhance biodegradable capacity, chemical coagulation and electrochemical oxidation were applied to pretreatment processes. FeSO(4).7H2O, pH 12 and 20 mmol/l were determined as optimal chemical coagulation condition; and 15 mA/cm2 of current density, 10 ml/min of flow rate and pH 7 were chosen for the most efficient electrochemical oxidation condition at combined treatment. The wastewater which consisted mainly of isothiazolin-ones and sulfide was efficiently treated by chemical coagulation and electrochemical oxidation. The optimal pretreatment processes showed 60.9% of chemical oxygen demand (COD), 99.5% of S(2-) and 96.0% of isothiazolin-ones removal efficiency. A biological treatment system using membrane bioreactor (MBR) adding powder-activated carbon (PAC) was also investigated. COD of the wastewater which was disposed using a MBR was lower than 100 mg/l.


Assuntos
Antibacterianos/análise , Eletroquímica/métodos , Oxigênio/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Reatores Biológicos , Carbono/química , Eletrólitos , Desenho de Equipamento , Concentração de Íons de Hidrogênio , Modelos Químicos , Compostos Orgânicos/análise , Oxigênio/metabolismo , Temperatura , Tiazóis/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise
6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(4): 777-80, 2007 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-17608197

RESUMO

Magnetic photocatalysts (TiO2/Fe3O4), which are liable to be separated and recovered, were prepared using Fe3O4 as the support. The surface morphology and crystal pattern were investigated by means of XRD, SEM, XPS and FTIR. The results showed that TiO2 wraps on the surface of Fe3O4. The photocatalytic activity of the catalysts was investigated by photocatalytic decolorization of (TNR). The photocatalytic activity of the catalysts is high and the separating ratio is good.

7.
Nan Fang Yi Ke Da Xue Xue Bao ; 27(4): 458-60, 2007 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-17545030

RESUMO

OBJECTIVE: To analyze the factors affecting the accuracy of Osaka formula multiparameter ultrasound-based fetal mass estimation, thereby establishing new formulas to improve the accuracy of the estimation. METHODS: A retrospective review was conducted among 519 healthy women with singleton pregnancy. Three days before the delivery (between 37 and 42 weeks' gestation), ultrasonic measurement of the fetal weight and other indices of the fetus was routinely performed. Correlation and multiple linear stepwise regression analysis were used to correct the 3 equations, which, along with Osaka University formula, were used to predict another 219 fetuses' birth weight. The coincidence rate of the predicted value and with the actual birth weight, and the absolute error and relative error were compared between the equations. RESULTS: The fetal abdominal area (AA) and abdominal circumference (AC) showed the most conspicuous influence on the estimated fetal birth weight, and fetal humerus length (HL) was more sensitive than femur length (FL) for the estimation. Three new regression equations were established, among which the equation 2 (fetal birth weight=1082.859+4.116xAAxHL) showed the best accuracy in clinical prediction. CONCLUSION: AA,AC and HL are more sensitive indices for estimation of the fetal birth weight, and the equation 2 established in this study still awaits further verification for its clinical value.


Assuntos
Antropometria/métodos , Peso Fetal , Ultrassonografia Pré-Natal/métodos , Abdome/diagnóstico por imagem , Feminino , Humanos , Úmero/diagnóstico por imagem , Gravidez , Valores de Referência , Análise de Regressão , Estudos Retrospectivos
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(5): 698-700, 2005 May.
Artigo em Chinês | MEDLINE | ID: mdl-16128066

RESUMO

This paper studied the adsorption behavior of lab-made chitosan for acid dyeing waste water and basic dyeing waste waters, based on the effects of adsorbing time, deacetylation degree of chitosan, and pH of waste water. The results showed that the adsorption of basic fuchsin and saffron by the chitosan almost reached equilibrium state in 20 min. The adsorption capacities of the chitosan for dyes was comparable with activated carbon. Moreover, its dosages were only 2/3 of the latter. The adsorption process for Acid Red presented a dynamics character of first order reaction. FTIR spectroscopy was used to analyze the adsorption mechanisms of chitosan for different kinds of dyes. It was found that a great deal of hydroxide radicals in the chitosan molecule participated in the adsorption of basic fuchsin and saffron.


Assuntos
Quitosana/química , Corantes/química , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/química , Acetilação , Adsorção , Quitosana/farmacocinética , Crocus/química , Concentração de Íons de Hidrogênio , Hidróxidos/química , Cinética , Corantes de Rosanilina/química
9.
Huan Jing Ke Xue ; 26(3): 126-9, 2005 May.
Artigo em Chinês | MEDLINE | ID: mdl-16124484

RESUMO

The preparation of nanoscale oxide/polyvinylidene fluoride (PVDF) composite hollow fiber membrane by phase transition process was introduced. The effects of nanoscale titania and alumina particles on structure and property of composite hollow fiber membrane were investigated. The separation property, microstructure and crystalline phase of composite membranes were characterized by bovine serum albumin (BSA) rejection experiment, scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FT-IR), respectively. The results show that the properties of composite membrane are improved greatly compared to the pure PVDF membranes. The BSA rejection ratios of pure PVDF, Al2O3/PVDF and TiO2/PVDF membranes were 3.27%, 67.20% and 86.67%, respectively. The pure water fluxes of Al2O3/PVDF and TiO2/PVDF membranes were 2.3 and 2.6 times higher than that of pure PVDF membranes. Moreover, the pore size and its distribution of composite membrane characterized by nitrogen isothermal absorption measurement are smaller and narrower than pure PVDF membranes.


Assuntos
Óxido de Alumínio/química , Nanotubos , Polivinil/química , Titânio/química , Membranas Artificiais , Tamanho da Partícula , Espectrofotometria , Propriedades de Superfície
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(8): 936-7, 2004 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-15766112

RESUMO

The combustion temperature of solid propellant was measured in this paper. Emission spectra of the combustion flame were collected with remote sensing FTIR at the resolution of 4 cm(-1). The combustion temperatures with the burning time were calculated from the maximum spectral line intensity and the molecular rotation-vibration spectra of HF molecule, respectively. Combustion temperatures at each time were all 1 788.8 K from the maximum spectral line intensity method. For comparison, the temperatures calculated from the molecular rotation-vibration spectra were 1 859.7, 1 848. 3, 1 804.0 and 1 782.7 K, respectively. Results show that the two methods are all dependable in measuring combustion temperature of solid propellant. But the maximum spectral line intensity method is more convenient and rapid than the other when the combustion is relatively stable.

11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 23(3): 563-5, 2003 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-12953542

RESUMO

The present paper analysed in detail the reasons for the errors found in the literature when Boltzmann plot was used for the temperature measurement of a high-density plasma produced by electrothermal capillary discharge. The reliability of experiment can reach as high as 98%-99.5% and the error is only +/- 6.5% when the spectroscopic parameters, such as transition probability A, statistical weight of upper level g, and the energy of upper level Ei, are selected correctly for the temperature measurement of a high-density plasma produced by electrothermal capillary discharge by Boltzmann plot in atomic emission spectroscopy.

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