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1.
RSC Adv ; 14(7): 4362-4368, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38304568

RESUMO

Excessive carbon-dioxide emissions drive global climate change and environmental challenges. Integrating renewable biomass fuels with coal in power units is crucial for achieving low-carbon emission reductions. Coal blending with bio-heavy oil enhances the combustion calorific value of the fuel, improves combustion characteristics, and decreases pollutant emissions. This study found that bio-heavy oil with low sulfur (0.073%), low nitrogen (0.18%), low ash, and high oxygen (11.005%) content exhibits excellent fuel performance, which can be attributed to the abundant oxygen-containing functional groups (such as C[double bond, length as m-dash]O) in the alcohols, aldehydes, and ketones present in bio-heavy oil. Additionally, the residual moisture in coal-blended bio-heavy oil reduces the fuel's calorific value. The calorific value increases with a higher proportion of blended bio-heavy oil (28.1, 28.9, 32.1, 34.7, 40.6 MJ kg-1). Experiments on combustion flame shooting reveal that the combustion time of bio-heavy oils is significantly shorter than that of coal. As the proportion of blended bio-heavy oil increases, the flame height increases. Coal blending with bio-heavy oil involves three stages: water evaporation, volatile-matter decomposition, fixed-carbon combustion and mineral decomposition. This advances the combustion process and improves coal's ignition performance. Furthermore, the amount of gaseous pollutants (sulfur dioxide and nitrogen dioxide) in coal mixed with bio-heavy oil is relatively low, which is in alignment with the green environmental protection guidelines. The blending of coal with biomass fuel holds significant practical and strategic importance for developing high-efficiency, low-carbon, coal power units.

2.
Nanoscale ; 15(38): 15619-15625, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37712856

RESUMO

Perovskite-based photocatalysts have received significant attention for converting CO2 into fuels, such as CO, CH4 or long alkyl chains. However, the use of these catalysts is plagued by several limitations, such as poor stability, lead toxicity, and inadequate conversion efficiency due to the rapid recombination of carriers. Herein, a g-C3N4@Cs2AgBiBr6 (CABB) type II heterojunction photocatalyst has been prepared by growing lead-free CABB nanocrystals (10-14 nm) on the graphite-like carbon nitride (g-C3N4) nanosheet using the in situ crystallization method. The resulting nanocomposite, g-C3N4@CABB, demonstrated an efficient charge transfer pathway via a typical type II heterojunction. With formation rates of 10.30 µmol g-1 h-1 for CO and 0.88 µmol g-1 h-1 for CH4 under visible light irradiation, the nanocomposite exhibited enhanced photocatalytic efficiency in CO2 reduction compared to CABB and g-C3N4. The improved photocatalytic performance of the g-C3N4@CABB nanocomposite was attributed to the fabricated type II heterojunction, which boosted the interfacial charge transfer from g-C3N4 to CABB. This work will inspire the design of heterojunction-based photocatalysts and increase the fundamental understanding of perovskite-based catalysts in the CO2 photoreduction process.

3.
J Vis Exp ; (198)2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-37607103

RESUMO

Pericytes are crucial mural cells situated within cerebral microcirculation, pivotal in actively modulating cerebral blood flow via contractility adjustments. Conventionally, their contractility is gauged by observing morphological shifts and nearby capillary diameter changes under specific circumstances. Yet, post-tissue fixation, evaluating vitality and ensuing pericyte contractility of imaged brain pericytes becomes compromised. Similarly, genetically labeling brain pericytes falls short in distinguishing between viable and non-viable pericytes, particularly in neurologic conditions like subarachnoid hemorrhage (SAH), where our preliminary investigation validates brain pericyte demise. A reliable protocol has been devised to surmount these constraints, enabling simultaneous fluorescent tagging of both functional and non-functional brain pericytes in brain sections. This labeling method allows high-resolution confocal microscope visualization, concurrently marking the brain slice microvasculature. This innovative protocol offers a means to appraise brain pericyte contractility, its impact on capillary diameter, and pericyte structure. Investigating brain pericyte contractility within the SAH context yields insightful comprehension of its effects on cerebral microcirculation.


Assuntos
Hemorragia Subaracnóidea , Humanos , Pericitos , Encéfalo , Diagnóstico por Imagem , Circulação Cerebrovascular
4.
Entropy (Basel) ; 25(4)2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37190383

RESUMO

A hybrid scheme integrating the current waste heat recovery system (WHRS) for a silicon arc furnace with plasma gasification for medical waste is proposed. Combustible syngas converted from medical waste is used to drive the gas turbine for power generation, and waste heat is recovered from the raw syngas and exhaust gas from the gas turbine for auxiliary heating of steam and feed water in the WHRS. Meanwhile, the plasma gasifier can also achieve a harmless disposal of the hazardous fine silica particles generated in polysilicon production. The performance of the proposed design is investigated by energy, exergy, and economic analysis. The results indicate that after the integration, medical waste gave rise to 4.17 MW net power at an efficiency of up to 33.99%. Meanwhile, 4320 t of the silica powder can be disposed conveniently by the plasma gasifier every year, as well as 23,040 t of medical waste. The proposed design of upgrading the current WHRS to the hybrid system requires an initial investment of 18,843.65 K$ and has a short dynamic payback period of 3.94 years. Therefore, the hybrid scheme is feasible and promising for commercial application.

5.
Anal Chem ; 93(4): 1939-1943, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33427439

RESUMO

5-Hydroxymethylcytosine (5hmC) is a modified base present at low levels in various mammalian cells, and it plays essential roles in gene expression, DNA demethylation, and genomic reprogramming. Herein, we develop a label-free and template-free chemiluminescent biosensor for sensitive detection of 5hmC in genomic DNAs based on 5hmC-specific glucosylation, periodate (IO4+) oxidation, biotinylation, and terminal deoxynucleotidyl transferase (TdT)-assisted isothermal amplification strategy, which we term hmC-GLIB-IAS. This hmC-GLIB-IAS exhibits distinct advantages of bisulfite-free, improved sensitivity, and genome-wide analysis of 5hmC at constant reaction temperature without the involvement of either specially labeled nucleic acid probes or specific templates for signal amplification. This method can sensitively detect 5hmC with a detection limit of 2.07 × 10-13 M, and it can detect 5hmC in the whole genome DNA with a detection limit of 3.92 × 10-5 ng/µL. Moreover, this method can distinguish 5hmC from 5-methylcytosine (5mC) and cytosine (C) and even discriminate 0.1% 5hmC in the mixture of 5hmC-DNA and 5mC-DNA. Importantly, this hmC-GLIB-IAS strategy enables genome-wide analysis without the involvement of either isotope-labeled substrates or specific antibodies, providing a powerful platform to detect 5hmC in real genomic DNA with high reproducibility and accuracy.


Assuntos
5-Metilcitosina/análogos & derivados , Técnicas Biossensoriais/métodos , DNA/química , Medições Luminescentes/métodos , 5-Metilcitosina/química , Linhagem Celular Tumoral , Humanos
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