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121.
Anthraquinone and 1-aminoanthraquinone derivatives have been examined as thermal stabilizers or co-stabilizers for rigid PVC in air, at 180 °C. Their high stabilizing efficiency is detected by their high induction period values (Ts) when compared with some of the common reference stabilizers used industrially such as dibasic lead carbonate, calcium-zinc soap and octyl tin mercaptide. Blending these organic stabilizers with some of the reference stabilizers in different ratios had synergistic effect on both the induction period and the dehydrochlorination rate.A probable mechanism for the stabilizing mode of these derivatives has been proposed. The stabilizing efficiency is attributed partially to the stabilizers' ability to intervene in the radical chain degradation process of PVC and to the replacement of the labile chlorine atoms on PVC chains by a relatively more stable moiety of the organic stabilizer. 相似文献
122.
Fatama M. Abdel-Gawad Yousry M. Issa Mohamed E. M. Hassouna Emad M. Hussien 《Mikrochimica acta》2003,141(1-2):7-13
We describe new ion-selective electrodes for piribedil (PD) based on Bi(III)-iodide or Hg(II)-iodide piribedil ion associate
complexes in a poly(vinyl chloride) (PVC) membrane with dibutylphthalate (DBP) and dioctylphthalate (DOP) as plasticizing
solvent mediator. The electrodes (PD-[BiI4]/DBP, PD-[BiI4]/DOP, PD-[HgI4]/DBP and PD-[HgI4]/DOP) show nearly Nernstian response over the concentration range 2 × 10−5–10−2 M of the drug. The working pH ranges were 3.1–6.0, 3.5–6.0, 3.0–6.0 and 3.5–6.4, and the isothermal coefficients of the cells
were 0.00113, 0.00146, 0.00059 and 0.00120 V/°C for PD-[BiI4]/DBP, PD-[BiI4]/DOP, PD-[HgI4]/DBP and PD-[HgI4]/DOP, respectively. The selectivity coefficients for numerous compounds are given. The electrodes have been used for the
direct determination of PD in pure form and in tablets or in biological fluids by the standard addition and potentiometric
titration methods.
Received May 30, 2001; accepted June 24, 2002 相似文献
123.
Aron J. Huckaba Inés Garcia-Benito Hiroyuki Kanda Naoyuki Shibayama Emad Oveisi Sachin Kinge Mohammad K. Nazeeruddin 《Helvetica chimica acta》2020,103(5):e2000044
Perovskite solar cells have garnered and held international research interest, due to ever-climbing power conversion efficiency values, now >25 %. Some high efficiency configurations utilize a compact TiO2 layer underneath a mesoporous TiO2 layer, both of which require high temperature annealing steps that could hinder perovskite commercialization. To address the high thermal budget, we chose to use inkjet-printing to combine the two layers into a single TiO2 film, which incorporates both nanoparticle and molecular precursor as well as organic fullerene additives. We printed the ink on fluorine-doped tin oxide, and after annealing at various temperatures, we found that 400 °C was the optimum annealing temperature for the inkjet-printed electron transport layers, which is significantly lower than the 500 °C required to anneal typical mesoporous TiO2 films. 相似文献
124.
Emad A. Az‐Zo'bi 《Mathematical Methods in the Applied Sciences》2019,42(18):6216-6226
The simple equation method and modified simple equation method are employed to seek exact traveling wave solutions to the (1 + 1)‐dimensional van der Waals gas system in the viscosity‐capillarity regularization form. Under the help of Mathematica, new classes of kink solutions are derived. Numerical simulations with special choices of the free parameters are displayed by three‐ and two‐dimensional plots. The two methods demonstrate simplicity, reliability, and efficiency. 相似文献
125.
The theory of classical types of curves in normed planes is not strongly developed. In particular, the knowledge on existing concepts of curvatures of planar curves is widespread and not systematized in the literature. Giving a comprehensive overview on geometric properties of and relations between all introduced curvature concepts, we try to fill this gap. To complete and clarify the whole picture, we show which known concepts are equivalent, and add also a new type of curvature. Certainly, this yields a basis for further research and also for possible extensions of the whole existing framework. In addition, we derive various new results referring in full broadness to the variety of known curvature types in normed planes. These new results involve characterizations of curves of constant curvature, new characterizations of Radon planes and the Euclidean subcase, and analogues to classical statements like the four vertex theorem and the fundamental theorem on planar curves. We also introduce a new curvature type, for which we verify corresponding properties. As applications of the little theory developed in our expository paper, we study the curvature behavior of curves of constant width and obtain also new results on notions like evolutes, involutes, and parallel curves. 相似文献
126.
127.
Samaneh Saber-Samandari Saeed Saber-Samandari Mustafa Gazi Fevzi Ç. Cebeci Emad Talasaz 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(11):1133-1141
Nano-hydroxyapatite/cellulose-graft-polyacrylamide biocomposite hydrogels of different molar ratios were prepared to examine their potential application as a carrier for colon targeted drug delivery in vitro. The particle size of the synthesized nano-hydroxyapatite was found to be 122 nm. The swelling behavior of the composite hydrogels was observed in acidic and basic aqueous solution that simulated lower small intestine, colon and stomach fluids. The hydrogel could be applied in drug-delivery systems and acetylsalicylic acid was used as a model compound to test such a possibility. Finally, the synthesized biocomposite hydrogels with the 96.97% maximum encapsulation and 85.67% release efficiency in the basic medium were found to be a suitable candidate to carry and release of colon-targeted drugs. 相似文献
128.
Ali Abdulabbas Abdullah Emad A. Jaffar Al-Mulla Isam Hussain T. Al-Karkhi Saadon Abdulla Aowda 《Research on Chemical Intermediates》2013,39(6):2817-2823
The electrochemical behavior of complexes of fatty amides, synthesized from vegetable oil, with Cu(II) has been investigated. In this study, a platinum electrode was used in presence of DMSO as a medium. Reduction of Cu(II)/fatty amides complex was found with quasi-reversible reaction. The peak potential of voltammetric behavior of fatty amides is about ?0.77 V at a scan rate v = 0.1 V s?1 versus Ag|Ag+ electrode. This study shows that Cu(II)-fatty amides complex is poorly adsorbed on the electrode surface. Additionally, the copper complex form of fatty amides has a more stable structure than pure fatty amides to form the electrochemical reduction of the complex. 相似文献
129.
Emad A. Jaffar Al-Mulla Nor Azowa Bt Ibrahim Isam Hussain T. Al-Karkhi Kamyar Shameli Mohammed Zidan Mansor Bin Ahmad Wan Md. Zin Wan Yunus 《Research on Chemical Intermediates》2013,39(5):2133-2139
Fatty methylydrazides (FMHs) have been successfully synthesized from palm oil. Glycerol was produced as a by-product. The synthesis was carried out by reflux palm oil with methylhydrazine in hexane. FMHs have been characterized using elemental analysis, Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance technique. The results showed that a 6:1 molar ratio of palm oil to methylhydrazine, a round 78 % maximum conversion of palm oil into FMHs and a 10 h reaction time are the optimum reaction conditions. 相似文献
130.
Muhammed Mizher Radhi Emad A. Jaffar Al-Mulla Wisam H. Hoiwdy 《Research on Chemical Intermediates》2013,39(7):3173-3179
Frying oils were studied by Fourier-transform infrared (FT-IR) spectroscopy, in the range 4,000–200 cm?1, at different temperatures, in the liquid and solid states. The infrared spectrum at 15 °C was similar to that at 200 °C. The band at 730 cm?1 which was assigned to the rocking mode of (–CH2) disappeared at higher temperature because of the rotational isomerism which occurred in the oil structure. The activation energy (E a) of the disappearing (–CH2) band, calculated by use of the chemical dynamic method using the Arrhenius equation, is 8.45 kJ mol?1. The enthalpy difference (ΔH) between the two rotational isomer bands of the conformational structures of the oil at 730 and 1,790 cm?1, at different high temperatures, was also calculated, by use of the Van’t Hoff equation; the value obtained was ?10.85 kJ mol?1. 相似文献