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131.
Md. Abdul Gafur Md. Forhad Mina Md. Abu Hashan Bhuiyan Tsutomu Asano 《Polymer Degradation and Stability》2010,95(9):1818-1825
Talc-loaded isotactic polypropylene (iPP) composites with various contents of talc were fabricated by compression molding, following slow- and fast-cooling processes, to obtain slow-cooled samples (SCS) and fast-cooled samples (FCS), respectively. Lamellar thickness of the α-crystal of iPP in the SCS is observed to be larger than that in the FCS by X-ray diffraction study. Rolled fast-cooled samples (RFCS) were also prepared at 25 °C in order to examine the crystal growth of iPP. An epitaxial growth mechanism of the α-crystal of iPP from the talc crystal is proposed. Surface of talc-loaded FCS appears with a smaller particle size than that of talc-loaded SCS and RFCS as observed by a scanning electron microscope. Young’s modulus and tangent modulus of FCS are found lower than those of SCS with the addition of talc up to 20 wt% and higher above this concentration, except microhardness which is higher in SCS at all contents of talc. From thermal studies, talc-loaded SCS and FCS are found to show higher melting temperature than the neat samples. Effect of cooling and rolling on the structures and properties of the fabricated composites are elaborately discussed. 相似文献
132.
Pingli Liu Liang Huang Yuelie Lu Mina Dilmeghani Jean Baum Tingjian Xiang Jeff Adams Andrew Tasker Rob Larsen Margaret M. Faul 《Tetrahedron letters》2007,48(13):2307-2310
Synthesis of five and six membered heterocycles, indolines, 2,3-dihydrobenzofurans, chromans, isochromans, 1,2,3,4-tetrahydroquinolines, and 1,2,3,4-tetrahydroisoquinolines, in 70-99% yield by a ligand-free palladium catalyzed reductive Heck cyclization of phenyl bromides and chlorides, under mild conditions, is reported. Water was found to be essential for these reactions. 相似文献
133.
134.
In this work, we report a new catalytic oxidative desulfurization (CODS) system based on (TBA)PWFe/PVA/CTS nanohybrid film as a highly active catalyst. The nanohybrid material was successfully fabricated by the composition of tetra (n‐butyl) ammonium salt of Fe‐substituted phosphotungstate, ((n‐C4H9)4N)4[PW11Fe(H2O)O39] abbreviated as (TBA)PWFe, polyvinyl alcohol (PVA), and chitosan (CTS). The composite was characterized using various analytical techniques including FT‐IR, UV–vis, XRD, and SEM. The results revealed the hydrogen‐bonding interaction between inorganic (TBA)PWFe clusters and organic polymers. The catalytic activity of (TBA)PWFe/PVA/CTS was evaluated in the CODS of real gas oil. Also, the solutions of heterocyclic thiophenic compounds (HTCs) in n‐heptane were tasted as simulated fuels. It was found that the removal efficiency of HTCs in the presence of (TBA)PWFe/PVA/CTS catalyst reached as high as 95% at 60 °C after 2 h. The significant catalytic performance of the nanohybrid film might be attributed to its amphiphilicity and multifunctional active sites, which enhances adsorption and oxidation of sulfur compounds. Moreover, the (TBA)PWFe/PVA/CTS composite can be easily recovered and reused by simple filtration, making it a suitable catalyst for cleaner processing. 相似文献
135.
Mina F. Shehata Melanie A. Short Matthew A. Sanders Jennifer L. Roizen 《Tetrahedron》2019,75(24):3186-3194
A general approach to prepare unsymmetrical sulfamides is described. This method relies on the activation of sulfamic acid salts with triphenylphosphine ditriflate, and subsequent trapping by a nucleophilic amine. This strategy improves access to N-octadecyl-N′-propylsulfamide, a feeding suppressant. 相似文献
136.
Muhammad Muzammal Hussain Dr. Muhammad K. Majeed Prof. Haitao Ma Prof. Yunpeng Wang Dr. Adil Saleem Mina Lotfi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(2):e202103220
Organic resin cross-linking ZIF-67/SiO2 superhydrophobic (SHPB) multilayer coating was successfully fabricated on metal substrate. The perfluoro-octyl-triethoxy silane (POTS) modified ZIF-67 and SiO2 coating was applied on primary coated polytetrafluoroethylene (PTFE) and epoxy resin (EP) via spray coating method. Here, we present that the robust superhydrophobicity can be realized by structuring surfaces at two different length scales, with a nanostructure design to provide water repellence and a microstructure design to provide durability. The as-fabricated multilayer coating displayed superior water-repellence (CA=167.4°), chemical robustness (pH=1–14) and mechanical durability undergoing 120th linear abrasion or 35th rotatory abrasion cycle. By applying different acidic and basic corrosive media and various weathering conditions, it can still maintain superior-hydrophobicity. To get a better insight of interaction between inhibitor molecules and metal surface, density functional theory (DFT) calculations were performed, showing lower energy gap and increased binding energy of ZPS/SiO2/PTFE/EP (ZPS=ZIF-67+POTS) multilayer coating compared to the ZIF-67/SiO2/PTFE/EP, thereby supporting the experimental findings. Additionally, such coatings may be useful for applications such as anti-corrosion, self-cleaning, and anti-icing multi-functionalities. 相似文献
137.
Zohreh Mehri Lighvan Hossein Ali Khonakdar Abolfazl Heydari Mina Rafiee Maryam Dehdashti Jahromi Ali Derakhshani Amir Abbas Momtazi-Borojeni 《应用有机金属化学》2020,34(10):e5839
The organometallic palladium complex with nitrogen-containing heterocycles is a potent antitumor agent. Coordination of phosphorus ligands to organometallic complexes increases their hydrophilicity, promotes ligand−DNA interactions and damage level to cancer cells, and blocks division in target cells. In this study, a phosphaadamantane palladium complex ([Pd{(C,N)- (C12H8NH2)} (PTA) Cl], PTA = 1,3,5-Triaza-7-phosphaadamantane) ( 2 ) was synthesized via the reaction of biologically active PTA with binuclear palladacycles [Pd2{(C,N)-(C12H8NH2)}2(μ-Cl)2] ( 1 ). In vitro studies of the complex with DNA (calf-thymus) explored by UV–Vis, emission titration, circular dichroism and helix melting methods showed that the complex interacts with DNA via an intercalative mechanism. Furthermore, competitive binding studies using warfarin, digoxin and ibuprofen site markers containing definite binding sites revealed the binding of the complex to site I on bovine serum albumin. The in vitro release mechanism of the palladium complex exhibited a biphasic pattern characterized by an initial burst release followed by a slower sustained release. Ultimately, in vitro evaluation of cytotoxicity and cell death showed that the complexes were able to decrease the viability of human cancer cell lines (MCF-7 and Jurkat) in a dose-dependent manner, but lower decreases were observed in the viability of normal fibroblast cells ASF-4 at the dosages evaluated. Finally, the order of in vitro anticancer activities was found to be consistent with the DNA-binding affinities. 相似文献
138.
139.
Fayez M. Mina 《International Journal of Mathematical Education in Science & Technology》2013,44(5):525-529
In this paper the author attempts to build up an outline for a geometry syllabus in primary education. 相似文献
140.
Alfonso Zoleo Daria Confortin Nicola Dal Mina Marina Brustolon 《Applied magnetic resonance》2010,39(3):215-223
Samples from covers and endleaves of sixteenth to eighteenth century books in good conservation state from the Biblioteca
Nazionale Marciana in Venice have been investigated by means of electron paramagnetic resonance (EPR) spectroscopy and optical
microscopy to characterize the embedded paramagnetic species and to test differences and similarities of the materials in
the two types of book components. We detected the Mn(II), Fe(III), and Cu(II) paramagnetic ions, and analyzed their EPR signals
by comparing them with previous results in literature of EPR studies on paper. Interestingly, the Mn(II) EPR spectrum profile
appears as a fingerprint for samples coming from the same book, either from cover or endleaf, and it looks different for samples
extracted from different books. We discuss the role of EPR as a spectroscopic tool for characterizing the interaction of the
ions with the paper components and as possible agents of degradation. 相似文献