Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Más filtros













Intervalo de año de publicación
1.
Environ Res ; 197: 111040, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33771510

RESUMEN

The ceramic membrane has been widely used in the wastewater treatment based on the chemical resistance and superior separation performance. A robust and defect-free thin-film nanocomposite (TFN) nanofiltration (NF) membrane on the macroporous hollow fiber ceramic (HFC) substrate was novelly developed for heavy metals removal. Before interfacial polymerization (IP), the aqueous solution of graphene oxide (GO) grafted with ethylenediamine (EDA) was deposited on the HFC substrate by vacuum filtration. Then, a thin polyamide (PA) film was fabricated by EDA and 1,3,5-trimesoyl chloride (TMC), followed by heat treatment. The effects of GO content and EDA concentration on the performance of the NF membrane have been systematically investigated. The results showed that when the GO content was 0.015 mg·mL-1 and the EDA concentration was 0.75 wt.%, the as-prepared eGO3/PA-HFC membrane had a rejection rate of 94.12% for MgCl2 and a pure water flux of 18.03 L·m-2·h-1. Additionally, the removal ability of eGO3/PA-HFC membranes for heavy metal ions was satisfactory (93.33%, 92.73%, 90.45% and 88.35% for Zn2+, Cu2+, Ni2+ and Pb2+, respectively). The study explored further that it was efficient and stable for heavy metal ions removal during 30 h in the simulated tap water and mining wastewater, which indicated that the eGO/PA-HFC membrane has great application potential in wastewater treatment.


Asunto(s)
Grafito , Metales Pesados , Nanocompuestos , Cerámica
2.
RSC Adv ; 8(30): 16902-16909, 2018 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-35540524

RESUMEN

Here we reported a coordinating etching and precipitating method to synthesize a complex binary metal oxides hollow cubic structure. A novel NiCoO2/rGO composite with a structure of NiCoO2 nanocages anchored on layers of reduced graphene oxide (rGO) were synthesized via a simple template-assisted method and the electrochemical performance was investigated by cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy tests as a faradaic electrode for supercapacitors at a graphene weight ratio of 1 wt% (1%). When used as electrode materials for electrochemical capacitors, the NiCoO2/rGO composites achieved a specific capacity of 1375 F g-1 at the current density of 1 A g-1 and maintained 742 F g-1 at 10 A g-1. After 3000 cycles, the supercapacitor based on these nanocage structures shows long-term cycling performance with a high capacity of 778 F g-1 at a current density of 1 A g-1. These outstanding electrochemical performances are primarily attributed to the special morphological structure and the combination of mixed transition metal oxides and rGO, which not only maintains a high electrical conductivity for the overall electrode but also prevents the aggregation and volume expansion of electrochemical materials during the cycling processes.

3.
RSC Adv ; 8(51): 29455-29463, 2018 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-35548001

RESUMEN

Nanofiltration (NF) membranes with simultaneous high rejection of divalent cations and anions and high water permeation were designed and fabricated via interfacial polymerization (IP) on three-channel capillary ultrafiltration (UF) membranes. MWCNTs-COOH were modified with poly(amidoamine) (PAMAM) and the as-synthesized MWCNTs-PAMAM were embedded into the inner polyamide skin-layer of the NF membranes by incorporating them into a piperazine (PIP) aqueous solution, followed by IP with trimesoyl chloride (TMC). The rigid MWCNTs and the dendrimer PAMAM molecules endow the as-fabricated NF membranes with high porosity and good hydrophilicity. Additionally, the -NH2 groups of PAMAM introduce some positive sites into the polyamide layer. The as-prepared NF membranes with incorporated MWCNTs-PAMAM exhibit a pure water flux of 48.7 L m-2 h-1 and 92.6% and 88.5% rejection for Na2SO4 and MgCl2, respectively, at 4 bar. Moreover, the NF membranes display high rejection for sulfates and metal cations, including heavy metal ions. The practicability of the membranes for mine-wastewater treatment was tested, and the membranes showed above 80% rejection of heavy metals and solution flux of about 30 L m-2 h-1. In addition, their separation performance and stability were satisfactory during the long-term run. The high rejection of the membranes for metal cations is ascribed to the positive sites offered by MWCNTs-PAMAM and the narrow membrane pores since both electrostatic repulsion and size exclusion play a role during membrane filtration. The good separation performance of the membranes for multivalent anions and heavy metal cations illustrates their potential for applications in heavy metal wastewater treatment.

4.
Acta Pharmacol Sin ; 36(9): 1137-44, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26256403

RESUMEN

AIM: Ca(2+)-release-activated Ca(2+) (CRAC) channel, a subfamily of store-operated channels, is formed by calcium release-activated calcium modulator 1 (ORAI1), and gated by stromal interaction molecule 1 (STIM1). CRAC channel may be a novel target for the treatment of immune disorders and allergy. The aim of this study was to identify novel small molecule CRAC channel inhibitors. METHODS: HEK293 cells stably co-expressing both ORAI1 and STIM1 were used for high-throughput screening. A hit, 1-phenyl-3-(1-phenylethyl)urea, was identified that inhibited CRAC channels by targeting ORAI1. Five series of its derivatives were designed and synthesized, and their primary structure-activity relationships (SARs) were analyzed. All derivatives were assessed for their effects on Ca(2+) influx through CRAC channels on HEK293 cells, cytotoxicity in Jurkat cells, and IL-2 production in Jurkat cells expressing ORAI1-SS-eGFP. RESULTS: A total of 19 hits were discovered in libraries containing 32 000 compounds using the high-throughput screening. 1-Phenyl-3-(1-phenylethyl)urea inhibited Ca(2+) influx with IC50 of 3.25±0.17 µmol/L. SAR study on its derivatives showed that the alkyl substituent on the α-position of the left-side benzylic amine (R1) was essential for Ca(2+) influx inhibition and that the S-configuration was better than the R-configuration. The derivatives in which the right-side R3 was substituted by an electron-donating group showed more potent inhibitory activity than those that were substituted by electron-withdrawing groups. Furthermore, the free N-H of urea was not necessary to maintain the high potency of Ca(2+) influx inhibition. The N,N'-disubstituted or N'-substituted derivatives showed relatively low cytotoxicity but maintained the ability to inhibit IL-2 production. Among them, compound 5b showed an improved inhibition of IL-2 production and low cytotoxicity. CONCLUSION: 1-Phenyl-3-(1-phenylethyl)urea is a novel CRAC channel inhibitor that specifically targets ORAI1. This study provides a new chemical scaffold for design and development of CRAC channel inhibitors with improved Ca(2+) influx inhibition, immune inhibition and low cytotoxicity.


Asunto(s)
Bloqueadores de los Canales de Calcio/química , Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio/metabolismo , Urea/análogos & derivados , Urea/farmacología , Calcio/metabolismo , Diseño de Fármacos , Células HEK293 , Humanos , Células Jurkat , Proteínas de la Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Proteína ORAI1 , Molécula de Interacción Estromal 1 , Relación Estructura-Actividad
5.
Huan Jing Ke Xue ; 35(4): 1516-22, 2014 Apr.
Artículo en Chino | MEDLINE | ID: mdl-24946612

RESUMEN

Due to the importance as a famous scenic area in China and its special geographical position, heavy metal pollution in soils in Xihu Scenic Area has attracted great concerns. Typical heavy metals in surface soils (0- 20 cm) in Xihu Scenic Area was investigated using the grid sampling method and statistical analysis and Aregis approaches. It was suggested that there were anthropogenic accumulations of Cu, Zn and Pb in soils, and they were the main heavy metal pollutants in Xihu Scenic Area. The contents of Cu, Zn, Pb in soils are in the ranges of 4.6-197 mg x kg(-1), 11.1-885 mg x kg(-1) and 11.7-346 mg x kg(-1), respectively. The area with the highest 25% of Cu, Pb and Zn content located in the north-east part of the scenic area, which had lower ratios of green land, dense traffic roads and was characterized with high urbanization. Results of multiple comparison among different land uses and spatial cluster and outlier analysis revealed that those three main heavy metal pollutants Cu, Pb and Zn in Xihu Scenic Area were from traffic emissions. The purpose of this study was to provide basic data and theoretical bases for the ecological risk assessment of heavy metals in urban soils and environmental management of urban soils.


Asunto(s)
Monitoreo del Ambiente , Metales Pesados/análisis , Contaminantes del Suelo/análisis , China , Geografía , Suelo/química , Análisis Espacial , Urbanización
6.
Huan Jing Ke Xue ; 34(5): 1822-7, 2013 May.
Artículo en Chino | MEDLINE | ID: mdl-23914534

RESUMEN

The fouling behavior of UF membranes by secondary effluent of municipal wastewater was investigated using both original PVDF membranes and PVA, PVP and PMMA modified PVDF membranes. The results showed that the structure parameters of UF membranes were optimized by blending; PVP and PVA could effectively improve the hydrophilicity and permeate flux of the membranes. The hydrophilicity and structure properties of UF membrane had stronger effect on the anti-fouling properties. Pore plugging resistance was the main reason for the unrecoverable fouling. For UF membranes with stronger hydrophilicity, there was some flux reduction in the initial filtration, which was attributed to the formation of concentration polarization layer. However, this layer can be easily removed and the irreversible fouling index (r(ir)) was 0, thus guaranteeing the membrane a better anti-fouling property. The dense membrane surface could prevent low-molecular-weight pollutants from entering the internal pores of the membrane. For UF membrane with fully developed macropores in the cross-section and loose spongy layer structure, pollutants deposition to membrane internal pores, which would cause membrane pore plugging, could be effectively inhibited. In contrast, for membranes with porous surface and not fully developed macropores in the cross-section, pore plugging was more prone to occur. As a result, flux declined seriously and was difficult to be recovered by physical cleaning, which gave rise to the irreversible fouling.


Asunto(s)
Incrustaciones Biológicas , Filtración/instrumentación , Aguas del Alcantarillado , Eliminación de Residuos Líquidos/instrumentación , Biopelículas , Ciudades , Filtración/métodos , Polivinilos/química , Eliminación de Residuos Líquidos/métodos
7.
Beijing Da Xue Xue Bao Yi Xue Ban ; 42(6): 727-33, 2010 Dec 18.
Artículo en Chino | MEDLINE | ID: mdl-21170106

RESUMEN

OBJECTIVE: To investigate the efficacy and safety of alprostadil cream in management of female sexual arouse disorder (FSAD), and its appropriate dose for clinical prescription. METHODS: The volunteers were assigned randomly to four groups which received alprostadil cream in different dosage (500 µg, 700 µg and 900 µg) or placebo cream, respectively. The cream was applied to the clitoris and G-spot before coitus. The efficacy was assessed by comparing the satisfactory rate of sexual arousal, the score of female sexual function index (FSFI) and female sex disorder scale (FSDS) and the general appraised question (GAQ) before and after the treatment. The safety was evaluated by the adverse effects that appeared including symptoms, physical and biochemical examination. RESULTS: Totally, 400 women enrolled in this study with 374 assigned to the group for efficacy evaluation and 387 cases to the group for safety analysis. No significant difference was found among the four groups in the demographic characters and sexual baseline. The increase of satisfactory percentage of sexual arousal in the four groups (placebo, 500 µg, 700 µg and 900 µg) was 22.63%, 36.67%, 34.01%, and 44.29%, respectively (P<0.05), and the increase was statistically higher in the 900 µg group than in the placebo group (P<0.0167). The elevated FSFI score above the baseline in the treatment groups (900 µg 22.89, 700 µg 21.69, and 500 µg 20.71) were higher than that in the placebo group (14.68, P<0.05), while the reduced FSDS score below the baseline (900 µg 25.97, 700 µg 21.98, and 500 µg 20.27) were higher than that of the placebo (17.60, P<0.05). No significant difference was found in the four groups in GAQ (P=0.054). The main common adverse effect was topical stimulation. No adverse effect was reported in physical and biochemical examination, electrocardiogram (ECG) or Thinprep cytologic test (TCT). CONCLUSION: Alprostadil cream can treat female sexual arousal disorder effectively with the maximum effect at the dose of 900 µg and without significant adverse effect except for mild topical stimulation.


Asunto(s)
Alprostadil/administración & dosificación , Disfunciones Sexuales Psicológicas/tratamiento farmacológico , Vulva/efectos de los fármacos , Administración Cutánea , Alprostadil/efectos adversos , Método Doble Ciego , Femenino , Humanos , Satisfacción del Paciente , Resultado del Tratamiento , Cremas, Espumas y Geles Vaginales
8.
Huan Jing Ke Xue ; 31(5): 1333-8, 2010 May.
Artículo en Chino | MEDLINE | ID: mdl-20623873

RESUMEN

The present study was conducted to assess the effects of effluent from a wastewater treatment plant (WWTP) on goldfish in early life stage. Fertilized eggs of the goldfish were exposed to a serial of graded concentrations of the effluent for 30 d. The hatching and survival rates of goldfish were decreased and the freaky rate was elevated with increased effluent concentrations. Additionally, the growth of fry was inhibited, and both body length and body weight were significantly decreased at > or =20% of effluent (p < 0.05). vitellogenin (Vtg) in fry was induced by all exposure concentrations. However, concentration dependence was not apparent. The highest Vtg induction was observed at the exposure of 20% effluent, whereas the induction effects of Vtg were decreased at > 20% of effluent. After a period of culture in clean water, both body length and body weight of fish were significantly increased, and Vtg levels were significantly decreased (p < 0.05). The result demonstrates that the exposure of WWTP effluents in early life stage can cause a risk of fish feminization. Goldfish seem to be suitable in assessing environmental impact of endocrine-disrupting chemicals due to their sensitivity in early life stage.


Asunto(s)
Disruptores Endocrinos/toxicidad , Monitoreo del Ambiente/métodos , Carpa Dorada/crecimiento & desarrollo , Contaminantes Químicos del Agua/toxicidad , Cigoto/efectos de los fármacos , Animales , Eliminación de Residuos Líquidos/métodos
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(2): 259-62, 2006 Feb.
Artículo en Chino | MEDLINE | ID: mdl-16826901

RESUMEN

Four hundred ninety seven rapeseed samples, which feature multi-year, multi-loci and highly variant characteristics, were collected as a raw set. The NIR spectra were pretreated by scatter correction and mathematics treatments, and calibration models of fat acid composition of intact rapeseed were developed by using the algorithm method of modified partial least square (MPLS). Meanwhile, three types of sample cups with different capacity were used to screen the suitable calibration model for rapeseed quality breeding. The results showed that the calibration model of 8-gram-sample was the best, and the calibration determination coefficient was in the range of 0.74-0.98. The calibration effects of 3-gram-sample, which were similar to those of 0.6-gram-sample, were good with high determination coefficient (RSQ1, 1-VR) and low error (SEC, SECV). Therefore, the calibration set with multi-year and multi-loci samples can improve the accuracy and repeatability of NIRS models. The fat acids NIRS models of intact rapeseed developed could be introduced into breeding lines' selection, mutant screening and germplasm evaluation.


Asunto(s)
Brassica rapa/química , Ácidos Grasos/análisis , Espectroscopía Infrarroja Corta/métodos , Espectroscopía Infrarroja Corta/normas , Calibración , Modelos Estadísticos
10.
Genet. mol. biol ; 29(3): 533-538, 2006. graf
Artículo en Inglés | LILACS | ID: lil-450294

RESUMEN

Analysis of genetic main effects and genotype x environment (GE) interaction effects on the oil content of oilseed rape (Brassica napus L.) was conducted by using a genetic model for the quantitative traits of seeds in diploid plants. The experiments were carried out over two years with 8 parents and a diallel mating design, which produced F1 and F2 generations. We found that the oil content of rape was simultaneously controlled by embryo genetic effect, cytoplasmic effects and maternal genetic effect as well as GE interaction effects, with the cytoplasmic and maternal effects playing the main role. The results indicate that selection of maternal plants for high oil content would be more efficient than selection based on single seeds. Since the GE interaction effects accounted for 73.69 percent of the total genetic effects and were more important than the genetic main effects it seems that selection might be influenced by environmental conditions. The estimate of narrow-sense heritability for oil content was 73.52 percent with the interaction heritability being larger than the general heritability, indicating that the early generations can be used for selection for high oil content. The prediction of genetic effects suggested that the parent cultivars Youcai 601 and Gaoyou 605 were better than the other cultivars for increasing oil content during the breeding of B. napus. The implications for the quantitative trait loci mapping of seed traits interfered by these three genetic systems is also discussed.


Asunto(s)
Brassica napus/genética , Herencia , Exposición a Riesgos Ambientales , Sitios de Carácter Cuantitativo , Selección Genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA