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1.
It has come to our attention that this article, “Rheology, Morphology, and Estimation of the Interfacial Tension of Binary Blends Based on Low‐Density Polyethylene/Poly(trimethylene terephthalate) and High‐Density Polyethylene/Poly(trimethylene terephthalate)” by A. A. Shokri and S. E. Zamani was previously published under the title, “Rheology, Morphology and Estimation of Interfacial Tension of LDPE/EVA and HDPE/EVA Blends” by H. A. Khonakdar, S. H. Jafari, A. Yavari, A. Asadinezhad, U. Wagenknecht, in Polymer Bulletin 54, 75–84 (2005), . We have retracted the article, and offer our apologies to the authors of the original paper.  相似文献   
2.
In present paper, an atmospheric-pressure low-temperature plasma treatment of pyrolysis fuel oil (PFO) was investigated in dielectric barrier discharge plasma torch reactor. The effect of the applied voltage and the volume of feedstock, as the main parameters, on the cracking of PFO were studied. By increasing the applied voltage from 10 to 16 kV, the production rate of hydrocarbons containing methane, ethylene, acetylene, propane, propylene, and C4 rise 18 times. In this case, the production rate of hydrogen increases by approximately 14 times and reaches 7.27 × 10?3 mol/min for 16 kV. In the feedstock volume investigation, based on limitation of reactor volume, the production rate of hydrocarbons decreased from 0.44 × 10?3 to 0.15 × 10?3 mol/min by increasing volume of feedstock from 1 to 5 cc.  相似文献   
3.
In this work, the use of Fe3O4/geraphene oxide nanocomposite as an efficient catalyst for the synthesis of 5-sulfanyltetrazole derivatives of indoles, pyrroles, and 5-alkyl sulfanyltetrazoles is described. These compounds are readily obtained by the reaction of the starting heterocycles indoles, N-aryl pyrroles, alkyl thiocyanates, and trimethylsilyl azide in good to excellent yields. Moreover, Fe3O4/GO nanocomposite could be easily separated from the reaction mixtures by an external permanent magnet and reused at least six times continuously without significant reduction in the product yield and its catalytic activity.  相似文献   
4.
Polymer light-emitting devices were fabricated utilizing plasma polymerized thin films as emissive layers. These conjugated polymer films were prepared by RF plasma enhanced chemical vapor deposition using naphthalene as monomer. The effect of different applied powers on the chemical structure and optical properties of the conjugated polymers was investigated. Fourier transform infrared (FTIR) and Raman spectroscopies confirmed that a conjugated polymer film with a 3-D cross-linked network was developed. By increasing the power, products tended to form as highly cross-linked polymer films. The fabricated devices showed broadband Electroluminescence (EL) emission peaks with center at 535–550 nm. Photoluminescence (PL) spectra of plasma polymers showed different excimeric emissions, resulted from crosslinked architecture. As the plasma power increased, the optical properties showed two different domains; up to 200 W, EL, PL and UV–Vis spectra red-shifted and broadened significantly. At higher powers, a reverse behavior was observed. Also, the relation between the film structure and plasma species was investigated using optical emission spectroscopy.  相似文献   
5.
Russian Journal of Applied Chemistry - Linear alkylbenzene (LAB) is a cost-effective and biodegradable intermediate in the production of detergents and surfactants. Recently, due to the spread of...  相似文献   
6.
The synthesis and characterization of two new aluminate(Ⅲ) complexes with general formula K[AlCl3X] are reported. These compounds derived from aluminate trichloride and related salts. Potassium trichlorothiocyanoaluminate, PCTA, and potassium trichlorocyanatoalu-minate, PCCA, are two new ionic aluminate complexes. They can be easily synthesized in a nearly quantitative yield by using the direct reaction of AlCl3 and KX. The complexes were characterized by physico-chemical and spectroscopic methods. Theoretical calculations have been used for the extraction of structural and spectroscopic data of these new synthesized complexes. The antibacterial activities of such compounds were studied against the Staphylococcus aureus, Escherichia coli, Staphylococcus Epidermidis, Estreptococo B and Shigella.  相似文献   
7.
This paper presents a methodology for modeling slug initiation and growth in horizontal ducts. Transient two-fluid equations are solved numerically using a class of high-resolution shock capturing methods. The advantage of this method is that slug formation and growth in a stratified regime can be calculated directly from the solutions to the flow field differential equations. In addition, by using high-resolution shock capturing methods that do not contain numerical diffusion, the discontinuity generated by slugging in the flow field can be modeled with good accuracy. The two-fluid model is shown to be well-posed mathematically only under certain conditions. Under these circumstances, the two-fluid model is capable of correctly predicting and modeling the flow physics. When ill-posed, an unbounded instability occurs in the flow field solution, and the instability amplitude increases exponentially with decreasing mesh sizes. This work shows that there are three zones associated with slug formation. In addition, long wavelength slugs are shown to initiate from short wavelength waves. These short waves are generated at the interface of the two phases by the Kelvin-Helmholtz hydrodynamic instability. The results obtained through numerical modeling show good agreement with experimental results.  相似文献   
8.
Considering a piezo-plasma-like layer with finite thickness and hexagonal symmetry whose main symmetry axis is parallel to the z axis and approximating it by an isotropic medium, we study the coupling of the elastic wave with plasma properties of the medium with and without spatial dispersion and collisions. In this case we investigate the coupled surface quasi elasto-electromagnetic wave propagating on the interface of piezoelectric layer with vacuum. Furthermore, the coupling of elasticity and ion-acoustic waves is investigated.  相似文献   
9.
In this study, different types of graphene were synthesized to investigate hydrogen adsorption capacity at different pressures (0–34 bar) at room temperature (298 K). Graphene and nanoporous graphene were prepared by Chemical Vapor Deposition (CVD) method, using methane as a carbon source at a temperature of 900 °C over copper plates and nickel oxide nanocatalyst. The nickel oxide nanocatalyst was prepared by sol–gel method, whereas graphene oxide was prepared through modified Hummer's method. The products were characterized by X‐ray diffraction, field emission‐scanning electron microscopy, energy dispersive spectroscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller and Raman spectroscopy. The adsorption of hydrogen was done by volumetric method. High adsorption capacity was achieved in nanoporous graphene because of its high pore volume (2.11 cm3/g) and large specific surface area (850 m2/g). Hydrogen adsorption values for nanoporous graphene, graphene and graphene oxide were determined as 2.56, 1.70 and 0.74 wt%, respectively. In addition, the hydrogen adsorption of graphene nanostructures fitted nicely to the selected two‐parameter and three‐parameter adsorption isotherm models. The adsorption isotherm model coefficients have been found for a 0–34 bar pressure range. The parameter values for all adsorbents showed proper conformity to the model and experimental data. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
10.
It is shown that in magnetically quantized plasmas, static Debye screening is changed. Furthermore, it is shown that under special circumstances, two electrons in such media may attract each other. Article presented at the International Conference on the Frontiers of Plasma Physics and Technology, 9–14 December 2002, Bangalore, India.  相似文献   
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