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1.
ACS Appl Mater Interfaces ; 15(12): 15279-15289, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36921119

RESUMO

Here, the successful transformation of graphitic carbon with a high degree of graphitization and a nanoflake structure from pyrolytic tire carbon black was demonstrated. First, amorphous carbon black with a porous structure was obtained after pyrolysis and simple preacid treatments. Subsequently, the carbon black was converted into a highly graphitic structure at a relatively low temperature (850 °C) through a facile electrochemical route using molten salt, which is ecofriendly and has high potential for large-scale graphitization compared to conventional incineration techniques. Moreover, we further improved the crystallinity and uniformity of the product simultaneously by directly mixing the metal oxide catalyst Fe2O3 with a carbon precursor. The mechanism of this metal-catalyzed electrochemical graphitization has been discussed in detail. To confirm their potential in practical applications, the as-prepared graphitized nanoflakes were used as conductive additives for silicon anodes in lithium-ion batteries, which showed a performance comparable to those utilizing commercial Super-P additives, exhibiting an initial Coulombic efficiency of approximately 79.7% and a high capacity retention of approximately 45.8% after 100 cycles with a reversible capacity of 1220 mAh g-1 at a current rate of 400 mA g-1. Hence, successfully recovered waste-tire-derived carbon black utilizing a low-temperature Fe2O3-catalyzed electrochemical process opens a pathway in low-temperature graphitization toward a sustainable value-added application in the field of energy storage.

2.
J Microbiol Immunol Infect ; 55(4): 708-715, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35718718

RESUMO

BACKGROUND: Treatment for lower respiratory tract infection caused by multidrug-resistant organisms (MDRO) are often limited. This study explored the activity of different metal nanoparticles against several respiratory pathogens including MDROs. METHODS: Clinical isolates of carbapenem-resistant Acinetobacter baumannii (CRAB), carbapenem-resistant Klebsiella pneumoniae (CRKP), Pseudomonas aeruginosa, Haemophilus influenzae, methicillin-resistant Staphylococcus aureus (MRSA), and Streptococcus pneumoniae were tested for in vitro susceptibilities to various antibiotics and nanoparticles. Minimum inhibitory concentrations (MICs) of silver-nanoparticle (Ag-NP), selenium-nanoparticle (Se-NP), and three composites solutions ND50, NK99, and TPNT1 (contained 5 ppm Ag-NP, 60 ppm ZnO-nanoparticle, and different concentrations of gold-nanoparticle or ClO2) were determined by broth microdilution method. RESULTS: Fifty isolates of each bacterial species listed above were tested. Ag-NP showed lower MICs to all species than Se-NP. The MIC50s of Ag-NP for CRAB, CRKP, P. aeruginosa, and H. influenzae were <3.125 ppm, 25 ppm, <3.125 ppm, and <3.125 ppm, respectively, while those for S. pneumoniae and MRSA were >50 ppm and 50 ppm. Among CRAB, CRKP and P. aeruginosa, the MIC50s of ND50, NK99, and TPNT1 for CRAB were the lowest (1/8 dilution, 1/8 dilution, and 1/8 dilution, respectively), and those for CRKP (>1/2 dilution, 1/2 dilution, and 1/2 dilution, respectively) were the highest. Both MRSA and S. pneumoniae showed high MIC50s to ND50, NK99, and TPNT1. CONCLUSIONS: Metal nanoparticles had good in vitro activity against Gram-negative bacteria. They might be suitable to be prepared as environmental disinfectants or inhaled agents to inhibit the growth of MDR Gram-negative colonizers in the lower respiratory tracts of patients with chronic lung diseases.


Assuntos
Nanopartículas Metálicas , Staphylococcus aureus Resistente à Meticilina , Infecções Respiratórias , Antibacterianos , Bactérias , Carbapenêmicos , Farmacorresistência Bacteriana Múltipla , Haemophilus influenzae , Humanos , Klebsiella pneumoniae , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa , Streptococcus pneumoniae
3.
ACS Nano ; 15(7): 12324-12333, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34269062

RESUMO

Although high-entropy alloys have been intensively studied in the past decade, there are still many requirements for manufacturing processes and application directions to be proposed and developed, but most techniques are focused on high-entropy bulk materials and surface coatings. We fabricated high-entropy ceramic (HEC) nanomaterials using simple pulsed laser irradiation scanning on mixed salt solutions (PLMS method) under low-vacuum conditions. This method, allowing simple operation, rapid manufacturing, and low cost, is capable of using various metal salts as precursors and is also suitable for both flat and complicated 3D substrates. In this work, we engineered this PLMS method to fabricate high-entropy ceramic oxides containing four to seven elements. To address the catalytic performance of these HEC nanomaterials, we focused on CoCrFeNiAl high-entropy oxides applied to the oxygen-evolution reaction (OER), which is considered a sluggish process in water. We performed systematic material characterization to solve the complicated structure of the CoCrFeNiAl HEC as a spinel structure, AB2O4 (A, B = Co, Cr, Fe, Ni, or Al). Atoms in A and B sites in the spinel structure can be replaced with other elements; either divalent or trivalent metals can occupy the spinel lattice using this PLMS process. We applied this PLMS method to manufacture electrocatalytic CoCrFeNiAl HEC electrodes for the OER reaction, which displayed state-of-the-art activity and stability.

4.
Int Urol Nephrol ; 45(5): 1327-37, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23355027

RESUMO

PURPOSE: Diabetic nephropathy and proteinuria are important risk factors for both end-stage renal disease and cardiovascular events. The present study aimed to identify the factors associated with nephrotic-range proteinuria in patients with advanced diabetic nephropathy. METHODS: This cross-sectional study enrolled 386 diabetic patients with chronic kidney disease (CKD) stages 3-5, from our outpatient Department of Nephrology. Urinary protein-to-creatinine ratio was recorded. Additionally, other laboratory parameters, body mass index, blood pressure, comorbidities, and medications were also reviewed. RESULTS: The mean age of the patients was 65.1 ± 11.6 years. Among patients with CKD stage 3 and 4, the odds ratio (OR) for nephrotic-range proteinuria in relation with systolic blood pressure significantly increased starting from 121 mmHg (OR 7.04 and 11.79 for systolic blood pressure of 121-140 and ≥141 mmHg, respectively, in comparison with systolic blood pressure below 121 mmHg). In addition, serum phosphorus ≥4.7 mg/dl was associated with significantly higher risk (OR 15.45) for severe proteinuria, compared with a phosphorus level ≤2.6 mg/dl. Finally, hypertriglyceridemia ≥241 mg/dl was also associated with higher OR for severe proteinuria, compared with a triglyceride level ≤200 mg/dl. Similar associations were found in patients with CKD stage 5. CONCLUSIONS: Higher systolic blood pressure, serum phosphorus, and triglyceride levels are associated with nephrotic-range proteinuria in patients with diabetic nephropathy and CKD stage 3-5. Further studies should clarify whether a reduction in serum phosphorus would lead to a decrease in proteinuria in these patients.


Assuntos
Nefropatias Diabéticas/sangue , Nefropatias Diabéticas/urina , Proteinúria/urina , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/urina , Idoso , Pressão Sanguínea , Índice de Massa Corporal , Creatinina/urina , Estudos Transversais , Nefropatias Diabéticas/fisiopatologia , Feminino , Humanos , Hipertrigliceridemia/sangue , Falência Renal Crônica/sangue , Falência Renal Crônica/fisiopatologia , Falência Renal Crônica/urina , Masculino , Pessoa de Meia-Idade , Fósforo/sangue , Proteinúria/sangue , Insuficiência Renal Crônica/fisiopatologia
5.
Nanoscale Res Lett ; 6(1): 38, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27502660

RESUMO

Flexible dye-sensitized solar cells are fabricated using vertically aligned ZnO nanowire arrays that are transferred onto ITO-coated poly(ethylene terephthalate) substrates using a simple peel-off process. The solar cells demonstrate an energy conversion efficiency of 0.44% with good bending tolerance. This technique paves a new route for building large-scale cost-effective flexible photovoltaic and optoelectronic devices.

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