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Yield enhancement of matrix precursor in short carbon fiber reinforced randomly oriented carbon/carbon composite
Thakur Sudesh Kumar Raunija, Sharad Chandra Sharma, Anil Verma 한국탄소학회 Carbon Letters 9 Pages
한국탄소학회 Carbon Letters 2016, Vol.19 7 57-65 (9 pages)
real system was studied. The fourier transform infrared spectrometry (FTIR), thermogravimetric analysis (TGA), yield, yield rate, and yield impact were used to check the effect of stabilization and pressure on the yield of the matrix precursor and the end properties of the composite thereafter. The results showed that the yield increased with stabilization duration up to 20 h whereas it decreased for stabilization duration beyond 20 h. Further results showed that the stabilized matrix precursor... -
Study on urea precursor effect on the electroactivities of nitrogen-doped graphene nanosheets electrodes for lithium cells
Ki-Yong Kim, Yongju Jung, Seok Kim 한국탄소학회 Carbon Letters 7 Pages
한국탄소학회 Carbon Letters 2016, Vol.19 5 40-46 (7 pages)
find the optimum urea content, we tested three different ratios of urea to graphene oxide. The morphology of the composites was examined by field emission scanning electron microscope. Functional groups and bonding characterization were measured by X-ray photoelectron spectroscopy. Electrochemical properties were characterized by cyclic voltammetry in an organic electrolyte solution. Compared with thermally reduced graphene/sulfur (S) composite, nitrogen-doped graphene/S composites showed higher... -
Carbon rich fly ash and their nanostructures
Numan Salah, Sami S. Habib, Zishan H. Khan, Ahmed Alshahrie, Adnan Memic, Attieh A. Al-ghamdi 한국탄소학회 Carbon Letters 9 Pages
한국탄소학회 Carbon Letters 2016, Vol.19 3 23-31 (9 pages)
Carbon rich fly ash was recently reported to have compositions that are ideal for use as a precursor and catalyst for carbon nanotube growth. This fly ash powder is mostly composed of pure carbon, predominantly present as sp2. In this work, the effect of sonication time on the morphology and structural properties of carbon rich fly ash particles is reported. The obtained results show that ultrasound treatment is an effective tool for producing ultrafine particles/fragments with higher porosity,... -
Adsorption of lisinopril and chlorpheniramine from aqueous solution on dehydrated and activated carbons
El-Said I. El-Shafey, Haider A. J. Al-Lawati, Wafa S. H. Al-Saidi 한국탄소학회 Carbon Letters 11 Pages
한국탄소학회 Carbon Letters 2016, Vol.19 2 12-22 (11 pages)
Date palm leaflets were used as a precursor to prepare dehydrated carbon (DC) via phosphoric acid treatment at 150°C. DC, acidified with H3PO4, was converted to activated carbon (AC) at 500°C under a nitrogen atmosphere. DC shows very low surface area (6.1 m2/g) while AC possesses very high surface area (829 m2/g). The removal of lisinopril (LIS) and chlorpheniramine (CP) from an aqueous solution was tested at different pH, contact time, concentration, and temperature on both carbons. The... -
Cu²? ion reduction in wastewater over RDF-derived char
Hyung Won Lee, Rae-su Park, Sung Hoon Park, Sang-Chul Jung, Jong-Ki Jeon, Sang Chai Kim, Jin Do Chung, Won Geun Choi, Young-Kwon Park 한국탄소학회 Carbon Letters 7 Pages
한국탄소학회 Carbon Letters 2016, Vol.18 8 49-55 (7 pages)
Emission Spectrometer (ICP-AES), and Fourier transform infrared spectroscopy were used to characterize the char. The optimum pH for copper removal was shown to be 5.5, and the steam-treated char displayed the best copper removal capability. Ion exchange between copper ions and alkali/alkaline metal cations was the most important mechanism of copper removal by RDF char, followed by adsorption on functional groups existing on the char surface. The copper adsorption behavior was represented well by... -
Manufacturing and characteristics of PAN-based composite carbon fibers containing cellulose particles
Jee-Woo Yang, Da Young Jin, Ji Eun Lee, Seung Goo Lee, Won Ho Park 한국탄소학회 Carbon Letters 8 Pages
한국탄소학회 Carbon Letters 2015, Vol.16 No.3 7 203-210 (8 pages)
This study fabricated low thermal conductive polyacrylonitrile (PAN)-based carbon fibers containing cellulose particles while maintaining their mechanical properties. The high thermal conductivity of carbon fibers limits their application as a high temperature insulator in various systems such as an insulator for propulsion parts in aerospace or missile systems. By controlling process parameters such as the heat treatment temperature of the cellulose particles and the amount of cellulose added,... -
Activated carbons prepared from mixtures of coal tar pitch and petroleum pitch and their electrochemical performance as electrode materials for electric double-layer capacitor
Eunji Lee, Soon Hyung Kwon, Poo Reum Choi, Ji Chul Jung, Myung-Soo Kim 한국탄소학회 Carbon Letters 8 Pages
한국탄소학회 Carbon Letters 2015, Vol.16 No.2 2 78-85 (8 pages)
Activated carbons (ACs) were prepared by activation of coal tar pitch (CTP) in the range of 700°C-1000°C for 1-4 h using potassium hydroxide (KOH) powder as the activation agent. The optimal activation conditions were determined to be a CTP/KOH ratio of 1:4, activation temperature of 900°C, and activation time of 3 h. The obtained ACs showed increased pore size distribution in the range of 1 to 2 nm and the highest specific capacitance of 122 F/g in a two-electrode system with an organic... -
Modification of isotropic coal-tar pitch by acid treatments for carbon fiber melt-spinning
Mi Jung Yoo, Hyo Jun Ko, Yun-Soo Lim and Myung-Soo Kim 한국탄소학회 Carbon Letters 8 Pages
한국탄소학회 Carbon Letters 2014, Vol.15 No.4 3 247-254 (8 pages)
In this work, thermal treatment accompanied with different acid treatments was applied to a commercial coal tar pitch (CTP) to obtain a spinnable precursor pitch for carbon fiber. In the case of thermal treatment only, a relatively high reaction temperature of between 380°C and 400°C was required to obtain a softening point (SP) range of 220°C-260°C and many meso-phase particles were created during the application of high reaction temperature. When nitric acid or sulfuric acid treatment was... -
Effect of chemically reduced graphene oxide on epoxy nanocomposites for flexural behaviors
Seul-Yi Lee, Mi-Hwa Chong, Mira Park, Hak-Yong Kim, Soo-Jin Park 한국탄소학회 Carbon Letters 4 Pages
한국탄소학회 Carbon Letters 2014, Vol.15 No.1 9 67-70 (4 pages)
RGO loading amounts on the mechanical properties of the epoxy nanocomposites. It was found that the presence of RGO improved both flexural strength and modulus of the epoxy nanocomposites till the RGO loading reached 0.4 wt%, and then decreased. The optimum loading achieved about 24.5 and 25.7% improvements, respectively, compared to the neat-epoxy composites. The observed mechanical reinforcement might be an enhancement of mechanical interlocking between the epoxy matrix and RGO due to the uniq... -
Preparation and characterization of microporous NaOH activated carbons from hydrofluoric acid leached rice husk and its application for lead(II) adsorption
A. F. Hassan, A. M. Youssef 한국탄소학회 Carbon Letters 10 Pages
한국탄소학회 Carbon Letters 2014, Vol.15 No.1 8 57-66 (10 pages)
Three activated carbons (ACs) were prepared using NaOH (N) as an activating agent. Hydrofluoric acid pre-leached rice husk was used as a precursor. After leaching, the precursor was washed with distilled water, dried, crushed, and then sieved; a size fraction of 0.3-0.5 mm was selected for carbonization in the absence of air at 600°C. The carbonization product (LC) was mixed with NaOH at ratios of 1:2, 1:3, and 1:4 (wt of LC: wt of NaOH) and the produced ACs after activation at 800°C were...
