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1.
Molecules ; 28(24)2023 Dec 17.
Article in English | MEDLINE | ID: mdl-38138629

ABSTRACT

Hydrogen, ammonia, and methanol are typical carbon-neutral fuels. Combustion characteristics and pollutant formation problems can be significantly improved by their blending. In this paper, reactive molecular dynamics were used to investigate the pollutant formation characteristics of hydrogen/ammonia/methanol blended fuel combustion and to analyze the mechanisms of CO, CO2, and NOX formation at different temperatures and blending ratios. It was found that heating can significantly increase blending and combustion efficiency, leading to more active oxidizing groups and thus inhibiting N2 production. Blended combustion pollutant formation was affected by coupling effects. NH3 depressed the rate of CO production when CH4O was greater than 30%, but the amount of CO and CO2 was mainly determined by CH4O. This is because CH4O provides more OH, H, and carbon atoms for CO and CO2 to collide efficiently. CH4O facilitates the combustion of NH3 by simplifying the reaction pathway, making it easier to form NOX.

2.
J Oral Pathol Med ; 52(2): 136-144, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36207791

ABSTRACT

BACKGROUND: Oncostatin M receptor is an interleukin 6 receptor with great influence on inflammation and cancer progression. However, the function of oncostatin M receptor in oral squamous cell carcinoma remains unknown. METHODS: Oncostatin M receptor expression was explored with TIMER and TCGA databases. The mRNA and protein expressions of oncostatin M receptor were detected in oral tissues. The association between oncostatin M receptor expression and clinicopathological characteristics was analyzed, and the prognostic value of oncostatin M receptor was determined. Immune statues of oncostatin M receptor were analyzed by TIMER and TISIDB. The underlying mechanisms of oncostatin M receptor in oral squamous cell carcinoma was also explored preliminarily. RESULTS: Oncostatin M receptor was dysregulated in many cancers. Both mRNA and protein levels of oncostatin M receptor in oral squamous cell carcinoma tissues were significantly higher than that in normal oral tissues. Oncostatin M receptor expression was connected to differentiation, lymph node metastasis, tumor node metastasis (TNM) stage, perineural invasion and vascular invasion. Oncostatin M receptor expression was an independent prognostic factor associated with overall survivals. Oncostatin M receptor expression was significantly related to CD8+ T cell and interleukin 6 receptor. High oncostatin M receptor expression was associated with focal adhesion, extracellular matrix (ECM) receptor interaction, and JAK/STAT signaling pathway. CONCLUSION: Oncostatin M receptor was overexpressed in oral squamous cell carcinoma and related to overall survival. Oncostatin M receptor expression has potential to become an effective prognostic biomarker for oral squamous cell carcinoma patients.


Subject(s)
Carcinoma, Squamous Cell , Head and Neck Neoplasms , Mouth Neoplasms , Humans , Squamous Cell Carcinoma of Head and Neck , Carcinoma, Squamous Cell/pathology , Receptors, Oncostatin M/metabolism , Signal Transduction , Prognosis , RNA, Messenger
3.
J Environ Sci (China) ; 125: 319-331, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36375917

ABSTRACT

Oxidation-absorption technology is a key step for NOx removal from low-temperature gas. Under the condition of low O3 concentration (O3/NO molar ratio = 0.6), F-TiO2 (F-TiO2), which is cheap and environmentally friendly, has been prepared as ozonation catalysts for NO oxidation. Catalytic activity tests performed at 120°C showed that the NO oxidation efficiency of F-TiO2 samples was higher than that of TiO2 (about 43.7%), and the NO oxidation efficiency of F-TiO2-0.15 was the highest, which was 65.3%. Combined with physicochemical characteristics of catalysts and the analysis of active species, it was found that there was a synergistic effect between F sites and oxygen vacancies on F-TiO2, which could accelerate the transformation of monomolecular O3 into multi-molecule singlet oxygen (1O2), thus promoting the selective oxidation of NO to NO2. The oxidation reaction of NO on F-TiO2-0.15 follows the Eley-Rideal mechanism, that is, gaseous NO reacts with adsorbed O3 and finally form NO2.


Subject(s)
Nitrogen Dioxide , Oxygen , Catalysis , Oxidation-Reduction , Oxygen/chemistry , Titanium/chemistry , Ozone/chemistry , Nitric Oxide/chemistry
4.
Molecules ; 29(1)2023 Dec 28.
Article in English | MEDLINE | ID: mdl-38202760

ABSTRACT

This paper investigates the effect of equivalence ratio on pollutant formation characteristics of CH4O/H2/NH3 ternary fuel combustion and analyzes the pollutant formation mechanisms of CO, CO2, and NOX at the molecular level. It was found that lowering the equivalence ratio accelerates the decomposition of CH4O, H2, and NH3 in general. The fastest rate of consumption of each fuel was found at φ = 0.33, while the rates of CH4O and NH3 decomposition were similar for the φ = 0.66 and φ = 0.4. CO shows an inverted U-shaped trend with time, and peaks at φ = 0.5. The rate and amount of CO2 formation are inversely proportional to the equivalence ratio. The effect of equivalence ratio on CO2 is obvious when φ > 0.5. NO2 is the main component of NOX. When φ < 0.66, NOX shows a continuous increasing trend, while when φ ≥ 0.66, NOX shows an increasing and then stabilizing trend. Reaction path analysis showed that intermediates such as CH3 and CH4 were added to the CH4O to CH2O conversion stage as the equivalence ratio decreased with φ ≥ 0.5. New pathways, CH4O→CH3→CH2O and CH4O→CH3→CH4→CH2O, were added. At φ ≤ 0.5, new intermediates CHO2 and CH2O2 were added to the CH2O to CO2 conversion stage, and new pathways are added: CH2O→CO→CHO2→CO2, CH2O→CO→CO2, CH2O→CHO→CO→CHO2→CO2, and CH2O→CH2O2→CO2. The reduction in the number of radical reactions required for the conversion of NH3 to NO from five to two directly contributes to the large amount of NOX formation. Equivalent ratios from 1 to 0.33 corresponded to 12%, 21.4%, 34%, 46.95%, and 48.86% of NO2 remaining, respectively. This is due to the fact that as the equivalence ratio decreases, more O2 collides to form OH and some of the O2 is directly involved in the reaction forming NO2.

5.
Front Sociol ; 7: 843101, 2022.
Article in English | MEDLINE | ID: mdl-35399193

ABSTRACT

Mental health problems currently affect a quarter of the world's population. Recent research in western societies has started to examine the relationship between entrepreneurship and mental health problems such as Attention Deficit Hyperactivity Disorder (ADHD) and dyslexia. However, little has been done to categorize entrepreneurs into different types and investigate how their levels of mental health and well-being correspond to these types. This study divided entrepreneurs into established and nascent categories and examined this topic in Singapore. By distributing two sets of surveys, a total of 834 responses were collected, with 346 responses from established entrepreneurs and 488 responses from nascent ones. The results showed that the nascent entrepreneurs' levels of well-being were found to be much lower than those of the established entrepreneurs. Furthermore, entrepreneurs with ADHD or dyslexia symptoms generally had a much lower level of life satisfaction, compared with those without. However, the self-care behaviours observed in this sample differed somewhat from observations made in western societies, which might be explained by the different cultures and habits in Singaporean society. The findings not only highlight the need for relevant organizations to support nascent entrepreneurs but serve to remind veteran entrepreneurs to practice more healthy self-care behaviours.

6.
J Hazard Mater ; 412: 125258, 2021 06 15.
Article in English | MEDLINE | ID: mdl-33548788

ABSTRACT

Phosphomolybdic acid catalyst (PMoA/TiO2) is a promising catalyst for selective catalytic reduction of NOx with NH3 (NH3-SCR) due to its strong acidity and excellent redox property. This work presents the NH3-SCR reaction mechanism by In-situ diffuse reflectance Infrared Fourier Transform Spectroscopy (In-situ DRIFTs) and density functional theory (DFT). In-situ DRIFTs results indicated that the NH3-SCR performance over PMoA/TiO2 followed both Eley-Rideal (E-R) and Langmuir-Hinshelwood (L-H) mechanisms. The reaction pathway, intermediate, transition state and energy barrier over PMoA to complete NH3-SCR reaction were calculated by DFT. The results showed that the catalytic cycle includes foundational reaction (NH3 + NO reaction) and regenerative reaction (NH3 + NO2 reaction). NH2, NH2NO, HNNOH and HO2NNH species were the key intermediates. In the foundational reactions, NO2 played an important role in the removal of remaining H atoms. The NH3 dissociation on Lewis acid site, the internal hydrogen transfer on Brønsted acid site and the formation of HO2NNH species were the rate-controlling steps. The catalytic cycle of NH3-SCR over PMoA consists of standard SCR and fast SCR.

7.
ACS Omega ; 5(36): 23247-23256, 2020 Sep 15.
Article in English | MEDLINE | ID: mdl-32954175

ABSTRACT

Density functional theory is adopted to thoroughly analyze the influence mechanism of Fe on the formation of NH3 and HCN. The structure of Fe adsorbed on the surface of seven-membered zigzag coal containing pyridine nitrogen is selected as the Fe-containing coal model. The effect of Fe on the nitrogen distribution during Zhundong coal pyrolysis is further studied by thermogravimetry-mass spectrometry. The theoretical calculations show that Fe increases the Mulliken charge density on the N5 surface, which increases the rate-determining step energy barrier value of NH3 generated from coal pyrolysis and inhibits the NH3 formation. On the other hand, Fe significantly enhances the bonding energy between σ N5-C6 and π N5-C6, increases the activation energy required for N stripping from the pyridine ring (about 69.14 kJ/mol higher than that without Fe), and inhibits HCN formation. The experimental results show that Fe catalyzes the precipitation peaks of NH3 and CH3CN about 20 K ahead of time and has no obvious catalytic effect on HCN and HNCO. In terms of the nitrogen distribution, Fe significantly promotes the CH3CN formation and shows a significant inhibitory effect on NH3, HCN, and HNCO. Kinetic results show that Fe reduces the precipitation rates of NH3 and HCN, and the inhibitory effect on HCN is more significant.

8.
J Colloid Interface Sci ; 562: 429-443, 2020 Mar 07.
Article in English | MEDLINE | ID: mdl-31791698

ABSTRACT

A new ternary composite BiOIO3/MoS2/C500 was prepared via sol-gel and hydrothermal method. The energy bands, surface structures and optical properties of the as-prepared samples were characterized by XRD, SEM, TEM, UV-vis DRS, BET, XPS, PL, ESR and electrochemical measurement. The density functional theory (DFT) was adopted to explore the capability as well. It is discovered that BiOIO3/MoS2/C500 possesses excellent Z-scheme heterostructure for separating photogenerated electron-hole pairs mainly provided by BiOIO3/MoS2, and large specific surface area as charge carriers transfer channel mainly provided by C500, which can accelerate charges to transfer to the surface reaction area for photocatalytic oxidation. Then, the ternary catalyst was utilized to remove gas-phase Hg0 including its oxidation product, and possessed the highest removal efficiency of 78.32%, which is much higher than that of its pure component. Meanwhile, the photocatalytic activity of ternary catalyst are of high stability, and the product after the reaction is HgO and can be adsorbed on BiOIO3/MoS2/C500, which is detected by high resolution XPS. The loading manner provides a new vision for both photocatalysis and adsorption.

9.
J Cancer ; 10(19): 4473-4480, 2019.
Article in English | MEDLINE | ID: mdl-31528211

ABSTRACT

Background: The aim of this study was to confirm the role of nuclear pore membrane protein 121(POM121) in oral squamous cell carcinoma and to explore the underlying mechanism. Methods: POM121mRNA and protein expressions were evaluated in OSCC tissues and normal oral tissues by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry. The relationship between POM121 expression and clinical characteristics was analyzed. Bioinformatics analysis was performed to explore the possible mechanisms how POM121 affected OSCC. Results: We confirmed that POM121 mRNA expression in OSCC tissues was significantly higher than that in non-tumorous tissues, as was POM121 protein expression. POM121 expression was associated with distant metastasis and TNM stage. Multivariate analysis confirmed POM121 expression as an independent prognostic factor for OSCC patients. OSCC patients with high POM121 expression had a worse overall survival (OS) compared with patients with low POM121 expression. Bioinformatics analysis indicated POM121 may regulate OSCC through hedgehog and /or p53 signaling pathway. Conclusion: Targeting of POM121 expression levels could provide new diagnostic and therapeutic strategies for OSCC patients.

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