Log in to search using one of your social media accounts:

 

Effect of oxygen and hydrogen on microstructure of pyrolytic carbon deposited from thermal decomposition of methane and ethanol

Publication date: Available online 7 February 2018 Source:Journal of Solid State Chemistry Author(s): Biyun Ren, Shouyang Zhang, LiQun He, Shengyue Gu Chemical vapor infiltration (CVI) is the most extensive industrial preparation of carbon/carbon (C/C) composites. Precursor affects the CVI process considerably. In the present study, using carbon fiber bundles as preforms, methane and ethanol as precursors, the C/C composites were densified by decomposition of various gases in CVI. The thickness and texture of deposited pyrolytic carbon (PyC) were characterized by polarized light microscopy (PLM). The microstructure of PyC was analyzed by Raman spectroscopy. The morphologies of PyC were characterized by scanning electron microscopy (SEM). The composition of PyC was detected by X-ray photoelectron spectroscopy (XPS). Adding hydrogen in methane precursor resulted in a sharp decrease in the deposition rate and texture of PyC. Mixture of methane and ethanol as the precursor improved the deposition rate and texture remarkably. Besides, O element in ethanol was not remained as a constitution of PyC, and it was removed before the formation of PyC. Graphical abstract
Source: Journal of Solid State Chemistry - Category: Chemistry Source Type: research

Related Links:

The Daily Mail's resident GP answers your queries on everything and anything. This week,he deals with the effects of airport scanners, allergies chronic pain.
Source: the Mail online | Health - Category: Consumer Health News Source Type: news
In this work, it is proposed a new strategy to improve the dispersion of inorganic fillers in polymeric matrices by producing surface carbon nanostructures. Clay/carbon nanofibers particles were prepared and used as fillers to improve the mechanical and thermal properties of ultra-high molecular weight polyethylene (UHMWPE). Thermogravimetry (TG), differential scanning calorimetry (DSC), elemental analyses, Raman, X-ray diffraction (XRD) and scanning electron microscopy (SEM) showed that chemical vapor deposition (CVD) with ethanol at different temperatures, i.e. 700, 800 and 900 °C with and without Fe catalyst, can be...
Source: Journal of the Brazilian Chemical Society - Category: Chemistry Source Type: research
An imprinted amino-functionalized silica gel material was prepared by surface molecular imprinting technique combined with a sol-gel process on the supporter of activated silica gel and used as a solid-phase extraction for the extraction and determination of methyldopa (MTD). Non-imprinted silica adsorbent was synthesized without the addition of MTD using the same process. MTD-imprinted and non-imprinted silica adsorbents were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and the static adsorption experiments. The prepared MTD-imprinted silica sorbent demonstrated high ...
Source: Journal of the Brazilian Chemical Society - Category: Chemistry Source Type: research
This paper proposes a method for chicken tissues preparation using tetramethylammonium hydroxide (TMAH) for Pb determination by graphite furnace atomic absorption spectrometry employing multivariate approaches. Combining Raman spectroscopy with scanning electron microscopy coupled to energy-dispersive X-ray spectroscopy to monitor the solubilization process it was possible to show that TMAH acts in the solubilization of proteins, amino acids and lipids. Besides, this investigation showed that the small residual masses of samples have organic and inorganic compounds. Accuracy tests indicated that such residues have not inte...
Source: Journal of the Brazilian Chemical Society - Category: Chemistry Source Type: research
In this work, thermal properties and kinetics of Al-nanoparticles/ α -MnO2 nanorods thermite were reported. The α -MnO2 nanorods were synthesized using a hydrothermal method and were characterized by X-ray powder diffraction (XRD) and X-ray photoelectron spectra (XPS), then combined with Al nanoparticles based on the ultrasonic mixing method to prepare the nanostructure thermite. Besides, both pure components and mixture were characterized by field emission scanning electron microscopy (FE-SEM) to observe their morphologies and structures. Subsequently, the thermal properties of Al/ α -MnO2 nanostructure ...
Source: Journal of the Brazilian Chemical Society - Category: Chemistry Source Type: research
Chem. Commun., 2018, Accepted Manuscript DOI: 10.1039/C7CC09957F, CommunicationSharel E, Minkyung Kang, Paul Wilson, Lingcong Meng, David Perry, Andrew Basile, P. R. Unwin A strong relationship between surface structure and the redox activity of Li2O2 is visualized directly with scanning electrochemical cell microscopy, employing a dual-barrel nanopipette containing a unique gel polymer electrolyte.... The content of this RSS Feed (c) The Royal Society of Chemistry
Source: RSC - Chem. Commun. latest articles - Category: Chemistry Authors: Source Type: research
OBJECTIVES: To reconstruct a vehicle-bicycle-cyclist crash accident and analyse the injuries using 3D laser scanning technology, multi-rigid-body dynamics and optimized genetic algorithm, and to provide biomechanical basis for the forensic identification o...
Source: SafetyLit - Category: International Medicine & Public Health Tags: Engineering, Physics, Structural Soundness and Failure Source Type: news
Condition:   Healthy Interventions:   Drug: JNJ-55308942;   Drug: [18F]-JNJ-64413739 Sponsor:   Janssen-Cilag International NV Not yet recruiting
Source: ClinicalTrials.gov - Category: Research Source Type: clinical trials
DiscussionDr David Shulkin, a holdover appointee of President Obama who was nominated to be Secretary of Veterans Affairs by President Trump, was alleged by the VA Inspector General to have committed various ethical violations involving a trip to Europe the Secretary took with his wife.  This appeared to be just the latest in a string of travel-related scandals by top officials of the Trump administration.When this was first reported, I was inclined to see Dr Shulkin as an entitled, and conflicted  former health care executive who ran afoul of the government's strict ethical standards.  (Dr Shulkin'sofficial...
Source: Health Care Renewal - Category: Health Management Tags: Donald Trump ill-informed management mission-hostile management political ideology politics Veterans Affairs Source Type: blogs
Conclusions. We present our results in a question and answer fashion in order to make reading more interesting. RESULTS: PA should be searched in all high-risk populations. The gold standard for diagnosis PA is the plasma aldosterone/plasma renin ratio (ARR). If this test is positive, then we proceed with one of the four confirmatory tests. If positive, then we proceed with a localizing technique like adrenal vein sampling (AVS) and CT scan. If the lesion is unilateral, after proper preoperative preparation, we proceed, in adrenalectomy. If the lesion is bilateral or the patient refuses or is not fit for surgery, we tr...
Source: Endocrine Regulations - Category: Endocrinology Tags: Endocr Regul Source Type: research
More News: Chemistry | PET Scan | Study