Water flow in carbon nanotubes: the role of tube chirality

2019 ◽  
Vol 21 (12) ◽  
pp. 6566-6573 ◽  
Author(s):  
Alan Sam ◽  
Vishnu Prasad K. ◽  
Sarith P. Sathian

Flow rate of water in CNTs of different types.

Author(s):  
J. A. Thomas ◽  
A. J. H. McGaughey

Pressure-driven water flow through carbon nanotubes (CNTs) with diameters ranging from 1.66 nm to 4.99 nm is examined using molecular dynamics simulation. The flow rate enhancement, defined as the ratio of the observed flow rate to that predicted from the no-slip Hagen-Poiseuille relation, is calculated for each CNT. The enhancement decreases with increasing CNT diameter and ranges from 433 to 47. By calculating the variation of water viscosity and slip length as a function of CNT diameter, it is found that the results can be fully explained in the context of continuum fluid mechanics. The enhancements are lower than previously reported experimental results, which range from 560 to 100000, suggesting a miscalculation of the available flow area and/or the presence of an uncontrolled external driving force (such as an electric field) in the experiments.


Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2118
Author(s):  
Pierantonio De Luca ◽  
Carlo Siciliano ◽  
Anastasia Macario ◽  
Jànos B. Nagy

Four different types of multi-walled carbon nanotubes (MWCNTs) were used and compared for the treatment of benzoic acid contaminated water. The types of nanotubes used were: (1) non-purified (CNTsUP), as made; (2) purified (CNTsP), not containing the catalyst; (3) oxidized (CNTsOX), characterized by the presence of groups such as, –COOH; (4) calcined (CNTs900), with elimination of interactions between nanotubes. In addition, activated carbon was also used to allow for later comparison. The adsorption tests were conducted on an aqueous solution of benzoic acid at concentration of 20 mg/L, as a model of carboxylated aromatic compounds. After the adsorption tests, the residual benzoic acid concentrations were measured by UV-visible spectrometry, while the carbon nanotubes were characterized by TG and DTA thermal analyses and electron microscopy (SEM). The results show that the type of nanotubes thermally treated at 900 °C has the best performances in terms of adsorption rate and amounts of collected acid, even if compared with the performance of activated carbons.


2014 ◽  
Vol 105 (24) ◽  
pp. 243108 ◽  
Author(s):  
Filippo S. Boi ◽  
Serena Maugeri ◽  
Jian Guo ◽  
Mu Lan ◽  
Shanling Wang ◽  
...  

2016 ◽  
Vol 86 (3-4) ◽  
pp. 127-151 ◽  
Author(s):  
Zeshan Ali ◽  
Zhenbin Wang ◽  
Rai Muhammad Amir ◽  
Shoaib Younas ◽  
Asif Wali ◽  
...  

While the use of vinegar to fi ght against infections and other crucial conditions dates back to Hippocrates, recent research has found that vinegar consumption has a positive effect on biomarkers for diabetes, cancer, and heart diseases. Different types of vinegar have been used in the world during different time periods. Vinegar is produced by a fermentation process. Foods with a high content of carbohydrates are a good source of vinegar. Review of the results of different studies performed on vinegar components reveals that the daily use of these components has a healthy impact on the physiological and chemical structure of the human body. During the era of Hippocrates, people used vinegar as a medicine to treat wounds, which means that vinegar is one of the ancient foods used as folk medicine. The purpose of the current review paper is to provide a detailed summary of the outcome of previous studies emphasizing the role of vinegar in treatment of different diseases both in acute and chronic conditions, its in vivo mechanism and the active role of different bacteria.


1984 ◽  
Vol 52 (02) ◽  
pp. 172-175 ◽  
Author(s):  
P R Kelsey ◽  
K J Stevenson ◽  
L Poller

SummaryLiposomes of pure phospholipids were used in a modified APTT test system and the role of phosphatidyl serine (PS) in determining the sensitivity of the test system to the presence of lupus anticoagulants was assessed. Six consecutive patients with lupus anticoagulants and seven haemophiliacs with anticoagulants directed at specific coagulation factors, were studied. Increasing the concentration of phospholipid in the test system markedly reduced the sensitivity to lupus anticoagulants but had marginal effect on the specific factor inhibitors. The same effect was achieved when the content of PS alone was increased in a vehicle liposome of constant composition.The results suggest that the lupus anticoagulants can best be detected by a screening method using an APTT test with a reagent of low PS content. The use of a reagent rich in PS will largely abolish the lupus anticoagulant’s effect on the APTT. An approach using the two different types of reagent may facilitate differentiation of lupus inhibitors from other types of anticoagulant.


2020 ◽  
pp. 97-110
Author(s):  
E. N. Mikhailova ◽  
V. A. Telegina

The article is devoted to the study of evaluative tools used in modern French media in order to form the media image of a representative of the political elite. The techniques used in the creation of a memorial media portrait of Jacques Chirac (1932—2019), President of France from 1995 to 2007 are considered. The research material was the most prestigious French print media of various political orientations, published in late September — early October 2019 in connection with the death of the ex-President of the French Republic. The relevance of the research topic is dictated by the close attention of modern linguistics to axiological phenomena, differently presented in different types of discursive practices. The novelty of the study is due to the appeal to the analysis of the complex of evaluation tools used in the French print media when characterizing the former leader of the state during the nation’s farewell period. The estimated potential of the title of the article and its influence on the formation of the estimated vector of the entire text of the publication are shown. A systematic analysis of the assessment expression means, reflected in the memorial media portrait of the politician, is given. The factors that influenced the peculiarities of their use in this type of media portrait are revealed.


2020 ◽  
Author(s):  
Hua Jin ◽  
Lina Jia ◽  
Xiaojuan Yin ◽  
Shilin Wei ◽  
Guiping Xu

Misinformation often continues to influence people’s cognition even after corrected (the ‘continued influence effect of misinformation’, the CIEM). This study investigated the role of information relevance in the CIEM by questionnaire survey and experimental study. The results showed that information with higher relevance to the individuals had a larger CIEM, indicating a role of information relevance in the CIEM. Personal involvement might explain the effects of information relevance on the CIEM. This study provides insightful clues for reducing the CIEM in different types of misinformation and misinformation with varying relevance.


2009 ◽  
Vol 9 (4) ◽  
pp. 469-475
Author(s):  
T. Turtiainen

Radon is one of the contaminants that sometimes impair the water quality of wells, especially those drilled in bedrock. Domestic radon removal units based on aeration have been commercially available for more than ten years. In order to determine how effectively these units remove radon a new test protocol applying frequent sampling while letting 100 litres of water flow, was developed. This way, removal efficiencies can be more accurately calculated and possible malfunctions detected. Seven models of domestic aerators designed for removing radon from household water were tested. The aerators were based on diffused bubble aeration, spray aeration or jet aeration. The average removal efficiencies for 100 litres with a medium flow rate were 86–100% except for a unit that circulated the aerated water back to the well that had removal efficiency of 80% at the maximum. By conducting a questionnaire study usual problems related to the aeration units were localized and recommendations on maintenance and installation are given accordingly.


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