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1.
Langmuir ; 39(49): 17929-17938, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38015450

RESUMO

Currently, nickel sulfides are widely employed in the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), thanks to the narrow electronegativity difference of only 0.67 eV between nickel and sulfur. Among them, NiS stands out in terms of the OER performance; however, its HER performance and stability remain somewhat inadequate. The construction of heterogeneous interfaces can efficiently improve the HER performance and regulate the electronic structure of the NiS catalyst. CeO2 has been discovered to possess exceptional electronic modulation capabilities, which may lead to the effective enhancement of both HER and OER of the NiS catalyst. As a result, a nitrogen-doped carbon-coated CeO2-NiS heterogeneous interface catalyst (NC/NiS-CeO2) is designed as a bifunctional electrocatalyst for HER and OER with high performance. The NC/NiS-CeO2 catalyst demonstrates excellent HER (47 mV at 10 mA cm-2) and OER (92 mV at 10 mA cm-2) performances in a 1 M KOH alkaline solution. Characterization analysis reveals that the coupling of the heterostructure interface, which consists of CeO2 and NiS, significantly enhances electron conduction, the synergistic effect, and the electrocatalytic activity of the electrode. This study demonstrates that the HER and OER activity can be effectively improved by constructing a rational heterogeneous interface.

2.
Langmuir ; 39(37): 13189-13196, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37674321

RESUMO

Electrocatalytic hydrogen production has been a promising high-purity hydrogen production technology, attracting a large number of researchers' research interest. Ru has a hydrogen binding capacity similar to Pt, but its price is far lower than Pt, making it a promising alternative to Pt. However, a single Se electronic structure modulation is not sufficient to enable RuSe2 to be used for practical applications on a large scale due to the lack of electrons. Therefore, choosing a suitable way to electronically modulate the Ru atoms in RuSe2 can effectively improve the activity of the catalyst. Cobalt telluride (CoTe) can significantly enhance electrocatalytic performance due to tellurium's low electronegativity and excellent metal properties. In this work, the NC layer possesses excellent electrical conductivity and CoTe acts as an electron donor to optimize the electronic structure locally and trigger electron transfer efficiently. The RuSe2-CoTe/NC electrode requires an overpotential of only 25.4 mV (10 mA cm-2), which is superior to that of RuSe2/NF (65 mV) and CoTe/NC (115 mV). Meanwhile, the Tafel slope of RuSe2-CoTe/NC (67.8 mV dec-1) was better than that of RuSe2/NF (113.6 mV dec-1) and CoTe/NC (209.5 mV dec-1), showing that the build-up of the superior heterojunction makes the RuSe2-CoTe/NC with better hydrogen evolution reaction (HER) reaction kinetics. In addition, after 30 h of long-term stability testing, no significant decrease in catalytic activity was observed, proving the good stability of the RuSe2-CoTe/NC catalyst.

3.
Dalton Trans ; 52(36): 12852-12861, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37622402

RESUMO

Efficient spatial charge separation plays a crucial role in improving the photocatalytic performance. Therefore, 1T/2H MoSe2/BiOCl (1T/2H MS/BOC) and 2H MoSe2/BiOCl (2H MS/BOC) piezo-photocatalysts are synthesized. By combining piezoelectric catalysis and photocatalysis, a highly active piezo-photocatalytic process is realized. The optimal 1T/2H MS/BOC piezo-photocatalyst displays superior diclofenac (DCF) degradation and hydrogen (H2) evolution activity under the combined action of ultrasound and light. In particular, the DCF degradation kinetic constant (k) of optimal 0.5% 1T/2H MS/BOC under the synergistic effect of ultrasound and light is 0.057 min-1, which is 8.1 and 6.3 times higher than those of BiOCl (0.007 min-1) and 0.5% 2H MS/BOC (0.009 min-1). Moreover, the H2 evolution rate of 0.5% 1T/2H MS/BOC is 122.5 µmol g-1 h-1, which is also higher than those of BiOCl (45.8 µmol g-1 h-1) and 2H MS/BOC (49.5 µmol g-1 h-1). The dramatic improvement in the DCF degradation and H2 evolution piezo-photocatalytic performance of 1T/2H MS/BOC catalysts is ascribed to the built-in polarization electric field and abundance of active sites of 1T/2H MS/BOC as well as the advantageous band structure between BiOCl and 1T/2H MoSe2. Additionally, three probable degradation pathways of DCF were put forward from the results of liquid chromatography-mass spectrometry (LCMS) and density functional theory (DFT) calculations. This study provides the design strategy of high efficiency piezo-photocatalysts in environmental purification and energy-generation fields based on phase and band structure engineering.

4.
Dalton Trans ; 52(24): 8456-8465, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37272868

RESUMO

Stable and efficient bifunctional electrocatalysts are of great significance for sustainable energy conversion and human society sustainability. However, conventional electrocatalytic materials tend to exhibit high overpotentials and unsatisfactory chemical activities. Herein, we construct novel CoNi2S4/C3N4 nanowires on a nickel foam (NF) electrode as a bifunctional electrocatalyst for alkaline water splitting by a two-step hydrothermal and thermal annealing process. The prepared CoNi2S4/C3N4 electrocatalyst exhibits superior HER (e.g. 40 mV (ηH210)) and OER (e.g. 110 mV (ηO210)) activities in a 1 M KOH electrolyte, which are much smaller than those of bare NF, Co@NF, NiCoO@NF and most reported materials. Furthermore, the stability test at 10 mA cm-2 for 20 h for the CoNi2S4/C3N4 electrocatalyst shows no obvious decay and proves the excellent stability of CoNi2S4/C3N4. In this work, the unique tentacle-like CoNi2S4/C3N4 nanowire nanostructure leads to minimized interfacial resistance and abundant channels during electrocatalysis. Moreover, comprehensive analysis results show that Ni(Co)OOH active sites, which are beneficial for excellent OER activity, partially form on the surface of CoNi2S4/C3N4 during electrocatalysis. Finally, the CoNi2S4/C3N4∥CoNi2S4/C3N4 two-electrode system is constructed and it exhibits a low-voltage water splitting capability of 1.40 V.

5.
Inorg Chem ; 62(21): 8261-8270, 2023 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-37199449

RESUMO

The piezoelectric effect triggered by mechanical energy could establish an internal electric field to effectively modulate the separation behavior of carriers. Herein, a novel CdIn2S4/Bi2WO6 (CIS/BWO) piezo-photocatalyst for removing diclofenac (DCF) from water was constructed for the first time. Encouragingly, the photocatalytic degradation activity of CIS/BWO was effectively promoted through the piezoelectric effect. Specifically, 10% CIS/BWO exhibited promising DCF degradation performance under co-excitation of light irradiation and ultrasonic vibration, with a degradation efficiency of 99.9% within 40 min, much higher than that of pure photocatalysts (72.3%) and piezocatalysts (60.3%). Meanwhile, an in-depth study of the charge carrier separation mechanism of the CIS/BWO composite under the piezo-photo synergy condition was proposed. Both the built-in electric field induced by the piezoelectric effect in BWO and the Z-scheme transfer path of the CIS/BWO heterojunction are beneficial to interfacial charge transfer. Moreover, the Z-scheme mechanism was further demonstrated by trapping experiments and the electron spin resonance (ESR) technique. Finally, the corresponding intermediates of DCF over CIS/BWO composites and possible degradation pathways were also investigated by DFT calculations and liquid chromatography-mass spectrometry.

6.
Inorg Chem ; 61(45): 17972-17984, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36322117

RESUMO

Piezocatalysis is a promising technology to address environmental pollution by converting mechanical energy into chemical energy. Herein, MoSe2 nanosheets with different 1T phase percentages (ranging from 30 to 80%) were constructed by adjusting hydrothermal temperature. Moreover, the roles of phase engineering in the piezocatalysis were thoroughly investigated by degrading rhodamine B and reducing Cr(VI) in ultrasonic vibration conditions. In particular, MoSe2 prepared at 220 °C (MoSe2-220) exhibits ultrahigh observed constant kobs and degradation rate k, which is superior to most reported catalysts to date. The experimental results indicate that the introduction of the 1T phase increases the active sites of the material, improves the conductivity, and inhibits the recombination of electrons and holes. Moreover, an internal electric field in the 2H phase induced by piezoelectric polarization is facilitated to separate electron-hole pairs, enabling the degradation and reduction to proceed. The capture experiments and EPR tests further confirm that •O2- and •OH are main reactive species, and a rational mechanism is finally put forward. This study offers a clear understanding of phase engineering in piezocatalysis and provides an efficiency strategy to construct highly efficient piezocatalysts.

7.
Chemosphere ; 287(Pt 2): 132198, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34517238

RESUMO

97% of residential buildings are installed with secondary water supply system (SWSS) in China. In order to meet the water pressure demand, the SWSS has become a key solution to store and transport drinking water. The water age of the SWSS directly determines the quality of tap water, while total chlorine is a key indicator to evaluate the quality and safety of the water supply network. This study revealed the relationship between total chlorine and water age controlled by adjusting the liquid level of the secondary water supply tank. Models governing water age and the total chlorine concentration were developed based on the variation of the liquid level and the attenuation rate of the total chlorine in the SWSS. Furthermore, the validation was performed through case studies. The developed models can gain effective insights for determining the longest water age while guaranteeing the concentration of total chlorine meets the demand of the lower standard in SWSS. The secondary chlorine dosage would be quantified and added to the pipe network. The integration of the SWSS would be guided by water age in some old communities. The taste of tap water for direct drinking water could be improved by adjusting of water age using this model. The optimization method is easy to use for identifying efficient solutions for SWSS operation.


Assuntos
Água Potável , Purificação da Água , China , Cloro/análise , Água , Abastecimento de Água
8.
Materials (Basel) ; 14(16)2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34443282

RESUMO

Toughness of the coarse-grained-heat-affected-zone (CGHAZ) strongly depends on the prior austenite grain size. The prior austenite grain size is affected not only by chemical composition, thermal cycle, and dissolution of second-phase particles, but also by the initial microstructure. The effect of base metal microstructure (ferrite/pearlite obtained by air cooling and martensite obtained by water-quenching) on Charpy impact toughness of the CGHAZ has been investigated for different heat inputs for high-heat input welding of a microalloyed steel. A welding thermal cycle with a heat input of 100 kJ/cm and 400 kJ/cm were simulated on the MMS-300 system. Despite a similar microstructure in the CGHAZ of both the base metals, the average Charpy impact energy for the air-cooled base metal was found to be higher than the water-quenched base metal. Through thermo-kinetic simulations, it was found that a higher enrichment of Mn/C at the ferrite/austenite transformation interface of the CGHAZ of water-quenched base metal resulted in stabilizing austenite at a lower A1 temperature, which resulted in a coarser austenite grain size and eventually lowering the toughness of the CGHAZ.

9.
Water Res ; 185: 116099, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32739696

RESUMO

In addition to surface water and groundwater, rainwater is used as an important drinking water source in many parts of the world, especially in areas with serious water pollution or insufficient water resources. Conventional drinking water treatment technologies can remove dissolved organic matter and therefore reduce the formation of disinfection by-products (DBPs) during subsequent disinfection using surface water or groundwater as drinking water sources. However, little information has been known about the effect of conventional water treatment processes on DBP formation when rainwater is used as drinking water source. This study evaluated CX3R-type DBP precursors removal from rainwater by conventional drinking water treatments and the corresponding decrease of CX3R-type DBP (trihalomethanes (THMs), haloaldehydes (HALs), haloacetonitriles (HANs) and haloacetamides (HAMs)) formation and toxicity during the subsequent chlor(am)ination. The result showed that both sand filtration (SF) and activated carbon filtration (GAC) were able to remove DBP precursors and GAC outperformed SF, but no DBP precursors removal was observed during coagulation-sedimentation treatment. Among all treatments, SF + GAC was the most effective for DBP precursors removal, with removal efficiencies of 64.2% DOC, 98% DON and 76.6% UV254. Correspondingly, both SF and GAC decreased the formation of THMs, HALs, HANs and HAMs, and GAC performed better than SF. The combination of SF and GAC, especially SF + GAC, greatly decreased DBP formation, with average reduction of 79.2% and 85% during chlorination and chloramination respectively. After different treatments, the comprehensive toxicity risk of CX3R-type DBPs was all reduced, among which GAC + SF exhibited superior performance. Generally, the main contribution of integrated toxicity was HANs during chlor(am)ination. The formation potential of THMs, HALs, HANs and HAMs and the corresponding integrated toxicity were greater during chlorination than that during chloramination. Therefore, the combination of GAC and chloramination was promising in mitigating the comprehensive toxicity risk of THMs, HALs, HANs and HAMs for rainwater.


Assuntos
Desinfetantes , Água Potável , Poluentes Químicos da Água , Purificação da Água , Cloro , Desinfetantes/análise , Desinfecção , Halogenação , Trialometanos , Poluentes Químicos da Água/análise
10.
Int J Legal Med ; 134(3): 981-983, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31263947

RESUMO

To investigate the genetic polymorphism of Y chromosome short tandem repeat (Y-STR) loci in Dong, Miao, Tujia, and Yao minority populations from Hunan Province, China. Fifty Y-STRs (DYS392, DYS389I/II, DYS447, DYS438, DYS527, DYS645, DYS596, DYS391, DYS456, DYS19, DYS593, DYS448, DYS627, DYS557, DYS437, DYS481, DYS533, DYS390, DYS385, DYF387S1, DYS460, DYS393, Y_GATA_H4, DYS439, DYS635, DYS444, DYS643, DYS549, DYS576, DYS570, DYS458, DYS449, DYS518, DYS531, DYS630, DYS622, DYS552, DYS510, DYS459a/b, DYS446, DYS443, DYS587, Y_GATA_A10, DYS520, DYS522) were analyzed for 2553 unrelated healthy male individuals from Hunan (643 Dong males, 666 Miao males, 633 Tujia males, 611 Yao males) using AGCU Y37 and AGCU Y SUPP STR amplification system. There were 624 different haplotypes in 643 unrelated Dong males, 662 in 666 unrelated Miao males, 627 in 633 unrelated Tujia males, and 587 in 611 unrelated Yao males. The haplotype diversities of Dong, Miao, Tujia, and Yao were determined as 0.999879, 0.999982, 0.999970, and 0.999860, respectively. Analysis of molecular variance (AMOVA) tests demonstrated that genetic distance between Miao and Tujia was the smallest (0.0003), while the genetic distance between Dong and Yao was the largest (0.0252). The 50 Y-STR loci in the four minority populations from Hunan Province revealed a highly polymorphic genetic distribution, which showed a high potential for population genetics and forensic practice.


Assuntos
Cromossomos Humanos Y , Etnicidade/genética , Loci Gênicos , Genética Populacional/métodos , Haplótipos , Repetições de Microssatélites , Polimorfismo Genético , China/etnologia , Humanos , Masculino
11.
Sci Rep ; 6: 32737, 2016 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-27599572

RESUMO

Doxorubicin (Dox, Adriamycin) has been widely used in breast cancer treatment. But its severe cardio-toxic side effects limited the clinical use. Dox treatment can induce DNA damage and other accompanying effects in cancer cells, and subsequently activates nuclear factor κB (NF-κB) pathway which has a strong pro-survival role in different types of malignancy. We hypothesize that blocking NF-κB pathway may sensitize breast cancer cells to Dox chemotherapy. TGFß-activated kinase-1 (TAK1) is a key intracellular molecule participating in genotoxic stresses-induced NF-κB activation. Targeting TAK1 as a strategy to enhance cancer treatment efficacy has been studied in several malignancies. We showed that NG25, a synthesized TAK1 inhibitor, greatly enhanced Dox treatment efficacy in a panel of breast cancer cell lines. In this pre-clinical study, we found that NG25 partially blocked Dox-induced p38 phosphorylation and IκBα degradation and enhanced Dox-induced cytotoxic effects and apoptosis in all breast cancer cell lines tested. Taken together, we provided clear evidence that NG25 sensitizes the breast cancer cells to Dox treatment in vitro. This combination may be an effective and feasible therapeutic option maximizing Dox efficacy and meanwhile minimizing Dox side effects in treating breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Doxorrubicina/farmacologia , MAP Quinase Quinase Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , MAP Quinase Quinase Quinases/antagonistas & inibidores , Células MCF-7 , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos
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