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761.
It is well known that blowing agents (BAs) and polyol are essential components in polyurethane (PU) composition. Utilizing renewable sources in the material's formulation might reduce its environmental hazards while extending its possible engineering applications. In this study, the samples have been synthesized by using palm kernel oil-based polyol (PKOP). Water and sodium hydrogen carbonate (SHB) have been used as BAs. Scanning electron microscopy (SEM) has shown that adding the mix of BAs is causing the cells' average size to increase up to 227% and have reduced the lamellae width by up to 2% in comparison with the reference sample. The water tests have illustrated that combining two parts per hundred polyol by weight (php) water and 25 php SHB to the sample has increased its water capacity up to 617%. However, the samples are only able to retain 6% of the absorbed water at the 7th day. It has been also found that porosity has affected the water uptake and all the samples are following Fick's diffusion law, and diffusion is correlated to the square root of time. Multivariable power least squares method (MPLSM) and moving least squares method (MLSM) have been applied to find the relation between tear resistance value and BAs ratio. It is found that both methods have a dominant variable compared to the other variables, but MLSM provided optimizable equation with better R2. 相似文献
762.
Hydrothermal liquefaction (HTL) is the direct conversion of wet biomass into bio-oil at high temperature (200–400°C) and high pressure (10–25 MPa). In this work, we investigated HTL with 4.5 g of Chlorella and 45 ml of water/ethanol (1:1 vol. ratio) in a 100 ml reactor. Bio-oils produced are characterized via elemental analysis, thermogravimetric analysis, and gas chromatography–mass spectrometry (GC–MS). HTL of Chlorella was investigated at 240 and 250°C for 0 and 15 min under an air or H2 atmosphere and with and without 5% zeolite Y. Temperature increased the bio-oil yield from 38.75% at 240°C to 43.04% at 250°C for 15 min reaction time. Longer reaction time increased the bio-oil yield at 250°C from 39.14% for 0 min to 43.04% for 15 min. The H2 atmosphere had a significant effect for HTL at 240°C. Zeolite Y increased the bio-oil yield significantly from 32.03% to 43.06% at 250°C for 0 min. The carbon content of bio-oil increased with the temperature while the oxygen content decreased. The boiling point distribution of bio-oils in the range of 110–300°C varies with temperature, and atmosphere. At 240°C for 15 min, the 110–300°C range increased from 31.19% in air (240-15-air) to 39.25% in H2 (240-15-H2). The H2 atmosphere increased the content of hydrocarbons, alcohols, and esters from 69.61% in air (240-0-air) to 82.83% in H2 (240-0-H2). Overall, temperature, reaction time, atmosphere, and catalyst all significantly influenced the yield and/or quality of bio-oils from HTL of Chlorella. 相似文献
763.
Joraid Ahmad A. Okasha Rawda M. Al-Maghrabi Mahdi A. Afifi Tarek H. Agatemor Christian Abd-El-Aziz Alaa S. 《Journal of Inorganic and Organometallic Polymers and Materials》2022,32(7):2653-2663
Journal of Inorganic and Organometallic Polymers and Materials - The objective of this work is to obtain the thermodynamic parameters (the changes in enthalpy, Gibbs free energy, and entropy) of... 相似文献
764.
Shaaban Saad Ferjani Hela Yousef Tarek Abdel-Motaal Marwa 《Journal of Inorganic and Organometallic Polymers and Materials》2022,32(5):1878-1890
Journal of Inorganic and Organometallic Polymers and Materials - A novel organoselenium compound named 4-((4-bromobenzyl)selanyl)aniline, C13H12BrNSe, (A), was synthesized via reduction of... 相似文献
765.
Paul Omdarshan Rajan Chithraja Samajdar Dip Prakash Hidouri Tarek Nasr Samia 《SILICON》2022,14(16):10475-10483
Silicon - A highly sensitive, accurate, fast and power efficient biosensor is the need of the hour. Undoubtedly, dielectrically modulated (DM) tunnel FET (TFET) assures better sensitivity as... 相似文献
766.
767.
Monir Minhaj Uddin Aziz Azrina Abd Karim Kaykobad Md. Rezaul Khatun Fatema Tarek Mostafa Yousuf Abu N. Vo Dai-Viet 《Topics in Catalysis》2023,66(1-4):64-74
Topics in Catalysis - The purpose of this research is to evaluate the intent of empty fruit bunches of palm oil (EFBpalm oil) to catalytic gasification of wood produced charcoal (Woodcharcoal) in... 相似文献
768.
Silicon - Renewable energy has become an auspicious alternative to fossil fuel resources due to its sustainability and renewability. In this respect, Photovoltaics (PV) technology is one of the... 相似文献