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

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RESUMEN: El objetivo fue evaluar las caracter ísticas de túbulos dentinarios expuestos por acción de diferentes protocolos de grabado en distintas zonas dentinarias. Se midió densidad tubular y diámetro. Se estudiaron 60 primeros premolares humanos sanos sometidos a tratamiento de endodoncia. Se realizaron cortes de las raíces a 5mm del l ímite amelocementario y en sentido longitudinal bucolingual, obteniendo mitades iguales (mesial y distal) que se agruparon según tratamiento acondicionador a recibir: Control, EDTA, H3PO4 15 y 45 seg., y H3PO4 15 y 45 seg. + NaOCl. S...
Source: Revista clinica de periodoncia, implantologia y rehabilitacion oral - Category: Dentistry Source Type: research
Conclusions: The effective healing of pressure ulcers is connected with laser irradiation at a wavelength of 658 nm. We believe that this effect is related to the inhibition of inflammatory processes in the wound and stimulation of angiogenesis and fibroblast proliferation at this specific radiation (based both on concentration of interleukins and TNF-α serum level and VEGF, TGFβ1, TNF-α activities in wound biopsies). Laser therapy at wavelengths of 940 and 808 nm does not significantly affect the above-mentioned repair processes, which explains its low effectiveness in the treatment of pressure ulcers. ...
Source: International Journal of Medical Sciences - Category: Biomedical Science Tags: Int J Med Sci Source Type: research
Philips Healthcare and Intel are reporting success from using computer central...Read more on AuntMinnie.comRelated Reading: Philips issues security advisory for cardiac PACS software Philips grows medical sales and profit in Q2 Philips wins FDA clearance for Ingenia Elition MRI scanner Philips to implement Dana-Farber's cancer support tool GE partners with Intel on digital imaging Gaming technology armed to reduce repeat x-rays
Source: AuntMinnie.com Headlines - Category: Radiology Source Type: news
This study aims to compare speech perception scores in quiet and noise of 6 DACI and 12 CI patients with advanced otosclerosis at 3 and 12 months after fitting. Preoperative computed tomographic scans of all patients were scored by experts using an existing otosclerosis grading system (stages 1 –3). Speech perception in quiet was significantly better for DACI compared to CI users at 3 months after fitting. At 12 months, no difference was found between DACI and CI patients. Speech perception scores in noise were significantly better in the DACI group. In summary, a DACI system seems to pr ovide an effective treatment ...
Source: Audiology and Neurotology - Category: Audiology Source Type: research
Facebook, under criticism for its business practices, seems to be branching off into other industries including medicine. Case in point is a partnership with NYU School of Medicine’s Department of Radiology to develop artificial intelligence (A...
Source: Medgadget - Category: Medical Devices Authors: Tags: Informatics Radiology Source Type: blogs
Publication date: December 2018Source: LWT, Volume 98Author(s): Yousof Farrag, Sara Malmir, Belén Montero, Maite Rico, Saddys Rodríguez-Llamazares, Luis Barral, Rebeca BouzaAbstractThis paper describes the preparation of thermoplastic starch edible films (TPS) loaded with donut-shaped starch microparticles from two different botanical origins. The microparticles were produced by a simple thermal aqueous-alcoholic treatment. The average size was 14.01 ± 2.65 μm and 28.61 ± 6.84 μm for the microparticles from corn and pea starch, respectively. The double helical A-type and C-type...
Source: LWT Food Science and Technology - Category: Food Science Source Type: research
CONCLUSION: Basic knowledge of these PET tracers, specifically their strengths, weaknesses, and indications for use, is essential to urologists and other physicians caring for patients with prostate cancer. PMID: 30125515 [PubMed - in process]
Source: Canadian Journal of Urology - Category: Urology & Nephrology Tags: Can J Urol Source Type: research
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Source: AuntMinnie.com Headlines - Category: Radiology Source Type: news
Publication date: Available online 21 August 2018Source: Journal of the Taiwan Institute of Chemical EngineersAuthor(s): Quoc-Thai Pham, Zong-Han Yao, Ya-Ting Chang, Fu_Ming Wang, Chorng-Shyan ChernAbstractLCST phase transition kinetics of aqueous poly(N-isopropylacrylamide) (PNIPAM) solutions was studied by using non-isothermal differential scanning calorimeter (DSC) and isothermal dynamic light scattering (DLS) techniques. The DSC data obtained from 5 and 10 wt% PNIPAM solutions were used in isoconversional kinetics analysis. The resultant large activation energy (Eα) and pre-exponential factor indicated that ...
Source: Journal of the Taiwan Institute of Chemical Engineers - Category: Chemistry Source Type: research
Publication date: 15 December 2018Source: Chemical Engineering Journal, Volume 354Author(s): Ying Zhu, Xiang Zhou, Jianbing Xu, Xiaoxia Ma, Yinghua Ye, Guangcheng Yang, Kaili ZhangAbstractHybrid explosive-nanothermite energetic composite is synthesized on silicon substrate by embedding hexanitrohexaazaisowurtzitane (CL20) with CuO/Al core/shell nanothermite arrays. The CL20 is in situ integrated with CuO/Al through a facile dissolution-recrystallization process utilizing the core/shell array structure. The hybrid energetic composite is characterized by field-emission scanning electron microscope, X-ray diffraction, and Fou...
Source: Chemical Engineering Journal - Category: Chemistry Source Type: research
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