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1.
J Colloid Interface Sci ; 579: 119-127, 2020 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-32574729

RESUMO

Antibiotics as newly emerging organic pollutants are arousing more and more serious environmental issues. Meantime, metal-organic frameworks (MOFs) are considered as promising adsorbents to remove antibiotics. To overcome the limitations of large-scale applications for MOFs in the powder form, herein, we proposed a strategy of in-situ growth ZIF-67 onto polyaniline (PANI) modified regenerated cellulose aerogel (RCA). First, RCA was obtained by chemical cross-linking and physical cross-linking method. Then, PANI played the role of metal chelated layers, which were coated on RCA by in-situ polymerization. Finally, ZIF-67 nanocrystals were in-situ growth on the surface of the PANI coated regenerated cellulose aerogel to synthesise the composite adsorbent ZIF-67/PANI/RCA. The loading mass ratios of ZIF-67 on RCA and PANI/RCA were 25.39% and 42.38%, respectively, which indicates that PANI as interface layers can effectively promote the in-situ growth of ZIF-67 compared with pure RCA. The obtained composite adsorbent (ZIF-67/PANI/RCA) was applied for the adsorption of tetracycline (TC) with high adsorption capacity (409.55 mg·g-1) and good recycling ability. After six cycles of adsorption-desorption, the removal efficiency toward TC was still over 94%. This strategy may provide an effective and versatile pathway to increase MOF loading mass on aerogel and sequentially branch out their applications in pollutant treatment fields.

2.
J Colloid Interface Sci ; 561: 211-219, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31816466

RESUMO

Composites of MOFs and aerogels (MOFACs), as a new class of nanostructured materials, attract increasing attention due to their favorable adsorption properties. Herein, UiO-66-NH2-CS aerogel monolith (UNCAM) was synthesized by covalent crosslinking with hierarchical structure, exhibiting effective and stable adsorption of Pb(II) ions. The aerogel monolith containing 50% MOF particles possesses a ultra-low density of 15.8 mg·cm-3, which is mainly attributed to the highly porous structure. Meantime, UNCAM can be described more suitable by the pseudo-second-order model and shows a higher mass transfer rate. The highest Pb(II) adsorption capacity of aerogel monolith is up to 102.03 mg·g-1 (1.612 × 106 mg·m-3), which is comparable to literature reports. The adsorption of Pb(II) by UNCAM is an endothermic and spontaneous process and consistent with the Langmuir model, indicating that the adsorption process belongs to monolayer adsorption and chemisorption. Furthermore, the adsorption mechanisms of coordination interaction between N and Pb (II) were confirmed, and the O also played a synergistic role in adsorption on a certain degree. Lastly, The UNCAM retained 90.12% adsorption ability after three cycles. This strategy may provide an effective and versatile pathway to convert the bulk MOF particles into a shapeable form and sequentially branch out their applications in pollutant treatment fields.

3.
Ying Yong Sheng Tai Xue Bao ; 23(1): 1-8, 2012 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-22489472

RESUMO

A pot experiment was conducted to study the effects of Eucalyptus grandis leaf litter during its early stage decomposition on the growth and the photosynthesis of Cichorium intybus. Each pot contained 12 kg soil mixed with different amounts of E. grandis leaf litter (30 g x pot(-1), A1; 60 g x pot(-1), A2; 90 g x pot(-1), A3; and 0 g x pot(-1), CK), and sowed with C. intybus. The growth indicators and the photosynthetic characteristics of C. intybus were measured after the third leaf of C. intybus seedlings fully expanded in treatment A3. At the early stage of leaf litter decomposition, the C. intybus biomass accumulation, leaf area growth, and synthesis of photosynthetic pigments were inhibited significantly, and the inhibition effect was getting stronger with the increasing amount of the leaf litter addition. The intercellular CO2 concentration of C. intybus was increased by litter addition, while the net photosynthetic rate, stomatal conductance, and transpiration rate were significantly lower than those of the control. With the increase of leaf litter addition, all the parameters of C. intybus light response and CO2 response except CO2 compensation point showed an obvious downward trend, and there existed significant differences between the treatments of litter additions and the control. It was suggested that during the decomposition of E. grandis leaf litter, its allelopathic substances released gradually and acted on receptor plants, inhibited the synthesis of photosynthetic pigments and the photosynthesis of the receptors, decreased the receptors environmental adaptation ability, and accordingly, inhibited the growth of C. intybus.


Assuntos
Chicória/crescimento & desenvolvimento , Eucalyptus/química , Feromônios/farmacologia , Fotossíntese/efeitos dos fármacos , Folhas de Planta/metabolismo , Chicória/fisiologia , Feromônios/metabolismo , Fotossíntese/fisiologia , Plântula/crescimento & desenvolvimento
4.
J Genet Genomics ; 38(4): 149-56, 2011 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-21530898

RESUMO

Osteogenesis imperfecta (OI, also known as brittle bone disease) is caused mostly by mutations in two type I collagen genes, COL1A1 and COL1A2 encoding the pro-α1 (I) and pro-α2 (I) chains of type I collagen, respectively. Two Chinese families with autosomal dominant OI were identified and characterized. Linkage analysis revealed linkage of both families to COL1A2 on chromosome 7q21.3-q22.1. Mutational analysis was carried out using direct DNA sequence analysis. Two novel missense mutations, c.3350A>G and c.3305G>C, were identified in exon 49 of COL1A2 in the two families, respectively. The c.3305G>C mutation resulted in substitution of a glycine residue (G) by an alanine residue (A) at codon 1102 (p.G1102A), which was found to be mutated into serine (S), argine (R), aspartic acid (D), or valine (V) in other families. The c.3350A>G variant may be a de novo mutation resulting in p.Y1117C. Both mutations co-segregated with OI in respective families, and were not found in 100 normal controls. The G1102 and Y1117 residues were evolutionarily highly conserved from zebrafish to humans. Mutational analysis did not identify any mutation in the COX-2 gene (a modifier gene of OI). This study identifies two novel mutations p.G1102A and p.Y1117C that cause OI, significantly expands the spectrum of COL1A2 mutations causing OI, and has a significant implication in prenatal diagnosis of OI.


Assuntos
Colágeno/genética , Mutação/genética , Osteogênese Imperfeita/genética , Alelos , Sequência de Aminoácidos , Grupo com Ancestrais do Continente Asiático/genética , Criança , Colágeno/química , Colágeno Tipo I , Feminino , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Osteogênese Imperfeita/diagnóstico por imagem , Linhagem , Gravidez , Diagnóstico Pré-Natal , Radiografia , Adulto Jovem
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(5): 1323-6, 2009 May.
Artigo em Chinês | MEDLINE | ID: mdl-19650481

RESUMO

Neodymium-doped gadolinium gallium garnet (Nd:GGG)crystal is the best operation material of solid-state heat-capacity laser. In the present paper, Nd:GGG single crystal was grown by Czochralski (Cz) method. Fluorescence spectra and absorption spectra were measured. At the same time, the spectral parameters of Nd:GGG laser crystal were calculated by Judd-Ofelt theory, including absorption and emission cross-section, intensity parameters, radiative transition probability, fluorescence branch ratio and fluorescent lifetime. According to the measurement and calculation of absorption spectra, it is illustrated that the main absorption peak of Nd: GGG crystal was at near 808 nm, the absorption cross section of the main peak at 808 nm sigma abs, was equal to 4. 35 x 10(-20) cm2. The FWHM of absorption line-width was equal to 8 nm, and the absorption intensity became stronger with the increase in Nd3+ ions concentration. According to the measurement and calculation of fluorescence spectra, the fluorescence emission peak was at near 1062 nm, which corresponds to 4F(3/2) - 4(I(11/2) emission band of Nd3+ ions. The radiative transition probabilityof the main emission peak at 1062 nm A(jj') was equal to 1 832.01 s(-1). The fluorescence branch ratio betajj was equal to 45.07%. The fluorescence lifetime r was equal to 250 micros. The stimulated emission cross section sigma(lamda) was equal to 21.58 x 10(-20) cm2. The laser operationof 4F(3/2) - 4I(11/2) transition can be realized due to the larger fluorescence branch ratio and stimulated emission cross section

6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(2): 335-8, 2008 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-18479017

RESUMO

Yb(x) : KY(1-x)W (x = 0.05)and KYbW crystals were grown by TSSG method. Both of the structure and spectral properties were compared. The condition for the crystal growth is: the rotation rate 10-15 r x min(-1), the pulling speed 1-2 d(-1), the growing period 10-15 d, cooling growing speed 0.05-0.1 degrees C x h(-1), and the cooling speed 20 degrees C x h(-1). X-ray powder diffraction analysis was performed for the crystal powder. They belong to beta-KYW structure with low thermal phase. The cell parameters of the two crystals were calculated, and they are respectively a1 = 1.063 nm, b1 = 1.034 nm, c1 = 0.755 nm, beta1 = 130.75 degrees, Z1 = 4 and a2 = 1.061 nm, b2 = 1.029 nm, c2 = 0.749 nm, beta2 = 130.65 degrees and Z2 = 4. The infrared spectrum and Raman spectrum of crystal were measured. The sample of Yb(x) : KY(1-x) W (x = 0.05) had stronger infrared absorption peaks at 925, 891, 840, 777 and 749 cm(-1), which were caused by stretching vibration. The sample of KYW had stronger infrared absorption peaks at 484 and 437 cm(-1) caused by bending vibration. The vibration modes were analysed and vibrational frequencies of vibratory activity was assigned. The two crystals had strong Raman activity. The vibration of WOOW and WOW exists from 200 to 1000 cm(-1).

7.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 17(10): 626-9, 2005 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-16259927

RESUMO

OBJECTIVE: To study the changes in serum contents of beta-endorphin (beta-EP), endothelins (ET), nitric oxide (NO) and tumor necrosis factor (TNF) after acute tetramethylene-disulfo-tetramine (TDT) poisoning and therapeutic effect of a new treatment regime. METHODS: (1) Forty-eight patients with tetramethylene-disulfo-tetramine poisoning (experiment group) were enrolled in this study. The serum levels of beta-EP, ET, NO and TNF were measured upon hospitalization and 1, 3, 5, 7, 9, 11, 13, 15, 17 and 19 days after poisoning, respectively, and compared with those of 30 healthy individuals (control group B). (2) They were treated with the improved regime and compared with patients treated with the conventional regime designated as control group A. RESULTS: (1) In 48 patients treated with improved regime, 45 were cured and 3 died. (2) The serum levels of beta-EP, ET, NO and TNF from 45 patients who were cured were significantly higher at hospitalization compared with those of healthy individuals, with the peak values appeared on day 1 after poisoning in the mild, moderate and severe groups. Beta-EP levels returned to normal range on days 9, 13 and 17 after poisoning respectively in the mild, moderate and severe groups. ET levels returned to normal range on days 7, 13 and 15 after poisoning respectively in the mild, moderate and severe groups. NO levels returned to normal range on days 7, 11 and 11 after poisoning respectively in the mild, moderate and severe groups. TNF levels returned to normal range on days 9, 11 and 17 after poisoning respectively in the mild, moderate and severe groups. (3) The serum levels of beta-EP, ET, NO and TNF in 3 non-survivors were very high at hospitalization and continued to increase in the course of treatment. (4) The cumulative doses of diazepam and Phenobarbital, and the eclampsia time were significantly less in the experiment group than those of control group A. CONCLUSION: (1) The serum levels of beta-EP, ET, NO and TNF are correlated with the severity of tetramethylene-disulfo-tetramine poisoning and general conditions of the patients. (2) When the serum levels of beta-EP, ET, NO and TNF decrease gradually in the course of treatment, prognosis is better. On the contrary, the prognosis is poor when their levels increase gradually. (3) Measures to decrease levels of beta-EP, ET, NO and TNF result in a better prognosis of patients with tetramethylene-disulfo-tetramine poisoning. (4) The improved regime can be considered a better therapeutic strategy in tetramethylene-disulfo-tetramine poisoning.


Assuntos
Hidrocarbonetos Aromáticos com Pontes/envenenamento , Endotelinas/sangue , Óxido Nítrico/sangue , Envenenamento/tratamento farmacológico , Fator de Necrose Tumoral alfa/sangue , beta-Endorfina/sangue , Doença Aguda , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Envenenamento/sangue
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