Effect of high temperature on reduction-controlling reaction rate of agricultural waste chars and coke with steelmaking slag

In the present research, mechanical and thermal properties of high-density polyethylene/wood flour were improved by incorporating nanoclay (Cloisite 30B) and antioxidant (Irganox B225) in the compound. Design of experiments was carried out to optimize composition among nine compounds and to investigate the effect of nanoclay and antioxidant (0–5 phr) and (0–0.4 phr), respectively. The results of mechanical tests showed approximately 24% increase in the tensile strength of compounds containing 2.5 and 5.0 part per hundred (phr) of the nanoclay in the composite compared with the same samples without nanoclay. The tensile modulus of composites increased 7.3% by increasing the level of nanoclay from 0 to 2.5 phr. However, a further increase in the nanoclay content led to a 4.3% decrease in tensile modulus. Evaluation of the thermal oxidation stability of samples confirmed that the thermal oxidation of composites decreased with increasing nanoclay from 0 to 5.0 phr and increased significantly with the addition of the antioxidant.

     

Laminar boundary layer on rotating sphere and spheroids in non-Newtonian fluids

Zusammenfassung Die dreidimensionalen Grenzschichtgleichungen für nicht-Newtonsche Flüssigkeiten werden in orthogonalen krummlinigen Koordinaten angegeben. In Kapitel 3 wird die von der Umdrehung einer Kugel in einer sonst ungestörten nicht-Newtonschen Flüssigkeit innerhalb der laminaren Grenzschicht erzeugte Strömung untersucht. Die Kapitel 4 und 5 behandeln in analoger Weise das verlängerte und verkürzte Sphäroid. In allen drei Fällen zeigen die Lösungen einen Zustrom an den Polen, der von einem Abfluss am Äquator ausgeglichen wird.     

Verhalten von Kieselsäure/Tonerde-Gel als Crack-Katalysator

Ohne Zusammenfassung     

Synthesis of N4-acylspermidines

N⁴-Acylspermidines have been synthesised in good yields from γ-aminobutyric acid and from spermidine.     

Synthesis and thermal properties of hybrid copolymers of syndiotactic polystyrene and polyhedral oligomeric silsesquioxane

Copolymerizations of styrene and the polyhedral oligomeric silsesquioxane (POSS)–styryl macromonomer 1‐(4‐vinylphenyl)‐3,5,7,9,11,13,15‐heptacyclopentylpentacyclo [9.5.1.1^3,9.1^5,15.1^7,13] octasiloxane have been performed with CpTiCl₃ in conjunction with methylaluminoxane. Random copolymers of syndiotactic polystyrene (sPS) and POSS have been formed and fully characterized with ¹H and ¹³C NMR, gel permeation chromatography, differential scanning calorimetry, and thermogravimetric analysis. NMR data reveal a moderately high syndiotacticity of the polystyrene backbone consistent with this use of CpTiCl₃ as a catalyst and POSS loadings as high as 24 wt % and 3.2 mol %. Thermogravimetric analysis of the sPS–POSS copolymers under both nitrogen and air shows improved thermal stability with higher degradation temperatures and char yields, demonstrating that the inclusion of the inorganic POSS nanoparticles makes the organic polymer matrix more thermally robust. The polymerization activity and thermal stability are also compared with those of reported atactic polystyrene–POSS copolymers. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 885–891, 2002; DOI 10.1002/pola.10175     

Asymmetric insertion of membrane proteins in lipid bilayers by solid-state NMR paramagnetic relaxation enhancement: a cell-penetrating Peptide example

A novel solid-state NMR technique for identifying the asymmetric insertion depths of membrane proteins in lipid bilayers is introduced. By applying Mn (2+) ions on the outer but not the inner leaflet of lipid bilayers, the sidedness of protein residues in the lipid bilayer can be determined through paramagnetic relaxation enhancement (PRE) effects. Protein-free lipid membranes with one-side Mn (2+)-bound surfaces exhibit significant residual (31)P and lipid headgroup (13)C intensities, in contrast to two-side Mn (2+)-bound membranes, where lipid headgroup signals are mostly suppressed. Applying this method to a cell-penetrating peptide, penetratin, we found that at low peptide concentrations, penetratin is distributed in both leaflets of the bilayer, in contrast to the prediction of the electroporation model, which predicts that penetratin binds to only the outer lipid leaflet at low peptide concentrations to cause an electric field that drives subsequent peptide translocation. The invalidation of the electroporation model suggests an alternative mechanism for intracellular import of penetratin, which may involve guanidinium-phosphate complexation between the peptide and the lipids.     

Determination of neptunium using high resolution sequential ICP-AES

In view to separate La(III), Pr(III) and U(VI) ions, from aqueous solutions, batch experiments are carried out for the sorption and desorption of these ions onto and from a novel functionalized resin. The sorption capacities varied from 1.06 to 47.30 mg/g and increased in the following order La(III), Pr(III) and U(VI), while yields desorption ranged from 73.0 to 94.3% and increased in the following order Pr(III), La(III) and U(VI). Considering the largest difference in sorption capacity and desorption yield of these three elements, at different operates conditions, this material can be potential candidate for the separation of U(VI), Pr(III) and La(III) ions from nuclear and other industrial wastewater.     

ZnO/PBAT nanocomposite films: Investigation on the mechanical and biological activity for food packaging

Packaging of foods in high barrier materials is essential to attain food safety. Nanocomposite technology is leading in search of the earlier said kind of packaging materials. The role of zinc oxide (ZnO) loadings on poly(butylene adipate‐co‐terephthalate) (PBAT) structure were investigated, in addition to that packaging properties such as barrier, thermal, and mechanical properties were studied. Antimicrobial films are developed based on PBAT and ZnO nanoparticles. The nanocomposites exhibits a significant increase in the mechanical and thermal stability. The resulting PBAT/ZnO nanofilms show superior antimicrobial activity against Escherichia coli and Staphylococcus aureus. Copyright © 2016 John Wiley & Sons, Ltd.     

Hydrothermal synthesis of LiMnPO<Subscript>4</Subscript>-C(sp<Superscript>2</Superscript>) hybrids,conductive channels,and enhanced dielectric permittivity: a modulated ionic conductor

A nanohybrid C-LiMnPO₄ is important to tailor its electrochemical properties useful for Li⁺-ion batteries and photo-catalysis. In this article, we report a simple in situ C-LiMnPO₄ synthesis, wherein the LiMnPO₄ grows from a supersaturated solution LiOH·H₂O, MnSO₄·H₂O, and H₃PO₄ in water at 200 °C in an autoclave in a hydrothermal reaction and bonds in situ to nascent carbon of a surface layer on a surface reaction with a long chain hydrocarbon used during the reaction. A phase pure C-LiMnPO₄ is formed in a shape of nanorods (Pnma orthorhombic crystal structure), with 100–150 nm diameters, 150–800 nm lengths, and 2–3 nm thickness of a co-bonded C-sp² surface layer. The LiMnPO₄ rigidly co-bonds to C-sp² via O^2? in the PO₄ ^3? polygons in a joint surface layer that a single molecular bonding extends well up to 600 °C, with a due mass loss on an extended heating in air. The sample contains fine pores with an average 3.0 nm diameter and a 9.0 m²/g surface area. At room temperature, it develops a huge dielectric permittivity ε _r~1.9 × 10⁵ near 1 Hz frequencies, which on raising the frequency decays progressively to a fairly steady ε _r~1.5 × 10³ at ≥1 kHz. Bare LiMnPO₄ is a low dielectric phase, ε _r < 10. A non-Debye type of dielectric relaxation is shown in the modulus plots. As frequency approaches to 10⁵ Hz, nearly three orders of larger ac conductivity, 2.5 × 10^?5 Scm^?1 at 10⁶ Hz, develop over a carbon-free LiMnPO₄ value useful for the applications.