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1.
Huan Jing Ke Xue ; 44(5): 2635-2645, 2023 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-37177937

RESUMO

Peracetic acid (PAA), as a new oxidant, has attracted increasing attention in the treatment of refractory organic pollution in sewage. In this study, the nano core-shell Co@NC catalyst was prepared via etching and used to activate PAA to degrade sulfamethoxazole (SMX) in sewage. The results indicated that the degradation rate of SMX reached 98%, and its reaction rate constant was 0.80 min-1 under optimal conditions (catalyst dosage=0.02 g·L-1, PAA concentration=0.12 mmol·L-1, pH=7, SMX concentration=10 µmol·L-1). With the increase in PAA concentration and core-shell Co@NC dosage, the degradation efficiency of SMX increased. The study found that the core-shell Co@NC/PAA system had the best degradation effect on SMX under near-neutral conditions (pH 6.0-8.0), and both acidic and alkaline environments were not conducive to SMX degradation. HCO3- and humic acid showed significant inhibition on the degradation of SMX, whereas Cl- showed weak inhibition. In addition, through a free radical quenching experiment and electron paramagnetic resonance (EPR) detection, acetoxy radical (CH3CO2CO3·) were the main active species for the degradation of organic pollutants in the system. Transformation products (TPs) of SMX were analyzed by U-HPLC-Q-Exactive Orbitrap HRMS, and a possible degradation path of SMX was proposed. At the same time, the catalyst recycling experiment showed that the nano core-shell Co@NC catalyst had good stability and reusability.

2.
Immunity ; 56(5): 926-943.e7, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-36948192

RESUMO

NOD-like receptors (NLRs) are pattern recognition receptors for diverse innate immune responses. Self-oligomerization after engagement with a ligand is a generally accepted model for the activation of each NLR. We report here that a catalyzer was required for NLR self-oligomerization. PELO, a well-known surveillance factor in translational quality control and/or ribosome rescue, interacted with all cytosolic NLRs and activated their ATPase activity. In the case of flagellin-initiated NLRC4 inflammasome activation, flagellin-bound NAIP5 recruited the first NLRC4 and then PELO was required for correctly assembling the rest of NLRC4s into the NLRC4 complex, one by one, by activating the NLRC4 ATPase activity. Stoichiometric and functional data revealed that PELO was not a structural constituent of the NLRC4 inflammasome but a powerful catalyzer for its assembly. The catalytic role of PELO in the activation of cytosolic NLRs provides insight into NLR activation and provides a direction for future studies of NLR family members.


Assuntos
Proteínas Reguladoras de Apoptose , Inflamassomos , Adenosina Trifosfatases/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas de Ligação ao Cálcio/química , Proteínas de Ligação ao Cálcio/metabolismo , Flagelina/metabolismo , Inflamassomos/metabolismo , Proteína Inibidora de Apoptose Neuronal/química , Proteína Inibidora de Apoptose Neuronal/metabolismo , Proteínas NLR/metabolismo
3.
Environ Technol ; : 1-15, 2022 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-36399153

RESUMO

With the wide application of polymer flooding technology in oil fields, wastewater containing PAM (polyacrylamide) is produced. Its high viscosity makes it difficult to degrade. In this paper, the low-temperature plasma produced by DBD (Dielectric Barrier Discharge) was studied to reduce the viscosity of wastewater containing PAM under the synergistic action of AC (Activated carbon)/Mn + TiO2 catalyst. The effects of different amount of AC/Mn + TiO2 catalyst, discharge voltage and initial concentration of solution on viscosity reduction were studied. The change of functional groups in wastewater containing PAM was detected by FTIR (Fourier transform infrared absorption spectrometer), and the mechanism of catalytic viscosity reduction was analysed. The AC/Mn + TiO2 catalysts were analysed by XPS (X-ray photoelectron spectroscopy), XRD (X-Ray Diffraction) and ESEM (Field emission electron microscopy). With the increase of discharge voltage, the effect of catalytic viscosity reduction is enhanced. After 10 min of discharge, the effect of catalytic viscosity reduction is significantly enhanced. The catalytic viscosity reduction is best when discharge voltage is 18 KV and discharge time is 30 min. The viscosity reduction of polyacrylamide solution by low-temperature plasma AC/Mn + TiO2 is significant. When the amount of AC/Mn + TiO2 catalyst added is 544 mg, the viscosity of polymer containing solution can be reduced from 1758 mPa·s to 11.9 mPa·s, and the shear rate can be changed from 0 1/sec to 30 1/sec after the discharge for 30 min. The functional groups in solution did not change significantly and the element composition of AC/Mn + TiO2 catalyst did not change before and after catalytic discharge.

4.
ACS Appl Mater Interfaces ; 12(28): 31079-31089, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32571008

RESUMO

Free radical polymerization is a mature method and can be used for preparing multifunctional hydrogels by simply changing the commercial monomers, but the harsh and time-consuming initiation conditions restrict its injectable ability, which further limits its application in the biomedical field. Though some catalysts can be used to accelerate the polymerization, their application is restrained by the biotoxicity. Hence, finding a biocompatible catalyzer for in situ free radical polymerization of hydrogels has a great prospect in biomedical application but is still challenging. In this study, we discovered that silver ions could catalyze free radical polymerization under ambient by transforming hydrone into hydroxyl radicals in the presence of ammonium persulfate, and the in situ-formed hydrogels prepared by this way showed great histocompatibility, hemocompatibility, cytocompatibility, and immunocompatibility. Benefitting from its convenience and biocompatibility, the in situ polymerization of polyacrylamide-based hydrogels for tissue adhesion, wound dressing, and conductive materials on the skin could be realized by simply blending diverse ingredients. Furthermore, this discovery may be a step toward the in situ-polymerized hydrogels for biomedical applications.


Assuntos
Resinas Acrílicas/química , Materiais Biocompatíveis/química , Hidrogéis/química , Prata/química , Radicais Livres/química , Polimerização
5.
Environ Sci Pollut Res Int ; 27(5): 5572-5583, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31853846

RESUMO

This study focused on enhanced electrokinetic remediation of Cr(VI) in real contaminated soil. The citric acid (CA) as the electrolyte and Fe(II) released from zero-valent iron (ZVI) under anoxic conditions functioned as the main reducer. They were used for overcoming the high insoluble Cr(VI) fraction in real contaminated soil and high Cr(VI) residue in acidic soil near the anode simultaneously. The synergism of CA and ZVI is that CA helps the release of Cr(VI) to react with the generated Fe(II) and alleviates the hindrance of Fe and Cr co-precipitates in electromigration of Cr; meanwhile, the end product Fe(III) from ZVI catalyzed the Cr(VI) reduction by CA. The removal of Cr(III) and Cr(VI) was significantly improved in real contaminated soil. The optimum result (82.86%) was obtained at a voltage gradient of 2.5 V/cm after 12-day remediation with a 10 g ZVI dose when the catholyte and anolyte were 0.2 mol/L and 0.1 mol/L CA, respectively. This configuration has a significant improvement in overcoming the current obstacles for Cr(VI) electrokinetic remediation from real contaminated soil and prospects for large-scale practical applications.


Assuntos
Cromo/química , Recuperação e Remediação Ambiental/métodos , Poluentes do Solo , Ácido Cítrico/química , Ferro/química , Solo
6.
Rev. ciênc. méd., (Campinas) ; 25(1): 41-47, jan.-abr. 2016. tab, ilus
Artigo em Português | LILACS | ID: biblio-833190

RESUMO

Objetivo Avaliar se o fotopolimerizador de uso odontológico (luz emissora de diodo) aplicado por 20 segundos sobre o cimento de ionômero de vidro convencional pode acelerar a presa química deste material. Métodos Os cimentos ionoméricos utilizados foram o Vidrion R (SS White, Rio de Janeiro) e o Ketac Molar (3M, Espe, Alemanha). Foram confeccionados quarenta corpos de prova divididos em quatro grupos (n=10): G1: Vidrion R sem fonte de luz; G2: Vidrion R ativadas por luz durante 20 segundos; G3: Ketac Molar sem fonte de luz; G4: amostras de Ketac Molar ativadas por luz durante 20 segundos. A espatulação do ionômero foi em quarenta segundos desde o início do processo até a perda do brilho. A fonte de luz foi o aparelho Optilight Max (Gnatus, São Paulo) com potência de luz de 1200mW/cm² e comprimento de onda de 450nm. Os resultados foram analisados no Programa Biostat (Analyst Soft, Walnut, Califórnia, Estados Unidos) versão 4.0, realizada a análise descritiva e o teste de Kruskal Wallis (Student-Newman-Keuls). Resultados A utilizaçãoda luz nos cimentos ionoméricos convencionais Vidrion R e Ketac Molar acarretou redução significativa no tempo gasto para a presa química destes materiais (p<0.01). Não houve diferença entre o tempo gasto para presa química com ou sem a utilização da fonte de luz, quando comparados os cimentos ionoméricos Vidrion e Ketac (p>0.05). Conclusão Autilização da fonte de luz emissora de diodo está indicada para acelerar a presa química inicial dos cimentos ionoméricos convencionais reduzindo o tempo operatório e favorecendo o tratamento em odontopediatria.


Objective To assess whether a dental light curing unit (light emission diode) used for 20 seconds on conventional glass-ionomer cement can accelerate chemical setting of the material. Methods The glass-ionomer cements used were Vidrion R (SS White, Rio de Janeiro, Brazil) and Ketac Molar (3M, Espe, Germany). Forty test specimens were fabricated and divided into 4 groups (n=10): G1: R Vidrion samples without using the light source; G2: Vidrion R samples light activated for 20 seconds; G3: Ketac Molar samples without using the light source; G4: Ketac Molar samples light activated for 20 seconds. In all groups the ionomer was spatulated for 40 seconds. The time elapsed from the beginning of the spatulation to the loss of gloss was recorded in seconds. The light source device was the Optilight Max (Gnatus, São Paulo, Brazil) with light output of 1200mW/cm² and a wavelength of 450nm. The software Biostat version 4.0 (Analyst Soft, Walnut, California) analyzed the results. Descriptive analysis was performed, and the Kruskal Wallis test was used (Student-Newman-Keuls). Results The use of light on conventional glass ionomer cements Vidrion R and Ketac Molar significantly reduced the time required for the chemical setting of these materials (p<0.01). The chemical setting time of the glass-ionomer cements Vidrion and Ketak did not differ with or without the light source (p>0.05). Conclusion The use of a light emission diode is indicated to accelerate the initial chemical setting of conventional glass-ionomer cements, reducing the operative time and improving treatment in pediatric dentistry


Assuntos
Catalisador , Luzes de Cura Dentária , Cimentos de Ionômeros de Vidro
7.
Int Surg ; 100(2): 304-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25692434

RESUMO

Our aim was to assess demographic and clinical characteristics of patients treated at our units who attempted suicide by self-incineration, and to compare the results of burns with or without catalyzer use. Twenty patients who attempted suicide by self-incineration were examined in terms of clinical and demographic characteristics. Average age of the study population was 35 years (range 13-85 years). Average percentage of total body surface area burn was 53% (9%-100%). Six (30%) patients used gasoline and 5 (25%) used paint thinner in order to catalyze burning. Of these 11 patients who used a catalyzer, 5 (45.4%) had inhalation injury and 7 (63.6%) died. Among 9 patients who did not use any catalyzer, 1 (11.1%) had inhalation injury and 4 (44.4%) died. In general, inhalation injury was diagnosed in 6 patients (30%) while 11 (55%) patients died. A high morbidity and mortality rate was found in patients who used a catalyzer.


Assuntos
Queimaduras/epidemiologia , Tentativa de Suicídio/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Demografia , Depressão/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Turquia/epidemiologia , Adulto Jovem
8.
Artigo em Coreano | WPRIM (Pacífico Ocidental) | ID: wpr-24814

RESUMO

Bone materials diggd up from the Haemi nameless martyrdom holy place burial sites were severely broken into fragments of various size, clay matrix filled the bone marrow cavities, grass roots were spreaded into the periosteum and the fragments were very soft enough to be flaken. To make permanent specimens, bony fragments impregnated within unsaturated polyester resin with catalyzer MEKP, promotor 8% cobalt octoate, and UV absorber. Permanent specimens were so very transparent that all the macroscopic structures can be observed, and they were hard enough not to be broken or cracked. This method of preserving bony fragments is considered to be used in archaeologic preservation and in making teaching materials of various human organs or tissues.


Assuntos
Humanos , Medula Óssea , Sepultamento , Cobalto , Métodos , Periósteo , Poaceae , Poliésteres , Materiais de Ensino
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