Solvent Migration and Drying Phbnoubnon of Polymeric Blends of Ethylene-Propylbnb Random Copolymbr and Isotactic Polypropylbnb in the Prbsbncb of Monocyclic Aromatic Liquids at Tbwbraturbs Bbtukbn 25-70°C.

ABSTRACT

Solvent sorption and drying performance of engineering polymeric blends of ethylene–propylene random copolymer and isotactic polypropylene in the presence of aromatic liquid: has been studied in the temperature interval 25–70°C. The drying of the polymer is studied from the desorption and redesorption experiments. The present results indicate that the rate of solvent migration and the drying phenomenon is controlled by internal mass transfer of solvent molecules within the polymer matrix. A technique is developed to study the sorption (S) –desorption (D) – resorption (RS)–redesorption (RD) i.e., S–D–RS–RD of the polymer sheets. The S–D–RS–RD experiments are a convenient measure of knowing the continuous weight loss of the polymer during long–term solvent exposure.     

Splittings, Satellites and Fine Structure in the Soft X-ray Spectroscopy of the Actinides

Perhaps the most demanding and powerful actinide spectroscopy is that using soft X-ray and VUV photons. Because of the relatively low energy and fairly small sampling depths of these photons and the corresponding electrons, it is necessary to use un-encapsulated samples with highly cleaned and well-prepared surfaces. This causes a myriad of sample containment problems for these radioactive materials. Despite these hindrances and difficulties, the soft-X-ray and ultra-violet spectroscopy of the actinides can provide an amazing level of detailed information, particularly having to do with 5f electronic structure. In this paper, the splittings, satellites and fine structure of the following actinide soft X-ray spectroscopies will be discussed: X-ray photoelectron spectroscopy; X-ray absorption spectroscopy; and inverse photoelectron spectroscopy, including Bremstrahlung isochromat spectroscopy and resonant inverse photoelectron spectroscopy.     

Promising Stability of Gold-Based Catalysts Prepared by Direct Anionic Exchange for DeNO x Applications in Lean Burn Conditions

Supported gold catalysts on γ-Al₂O₃ have been investigated in the catalytic reduction of NO _x in simulated Diesel exhaust gas conditions. Different parameters have been examined essentially the mode of gold incorporation via classical deposition–precipitation and anionic exchange methods and the nature of the pre-activation thermal treatment. The resistance to thermal ageing under reactive conditions at 500 °C was found completely different with a significant rate enhancement on anionic-exchange samples. Further comparisons also show that the nature of the pre-activation thermal treatment influences the extent of surface reconstructions during thermal ageing with a detrimental effect of reductive pre-treatment on the catalytic performances.     

Nanofiber Alumina Supported Lean NOx Trap: Improved Sulfur Tolerance and NOx Reduction

NO_x uptake and S resistance performance was studied over Pt–Ba and Pt–K lean NO_x trap (LNT) catalysts, supported on “standard” Al₂O₃ and a nanofibrous Al₂O₃. The activity study was accompanied by TEM, XRD and H₂ chemisorption characterization. The nanofibrous Al₂O₃-supported catalysts resulted in better performance. This included improved storage capacity, reduction efficiency during the regeneration phase, thermal stability and S-tolerance.     

Synthesis and Bacterial Mutagenicity of Oxidized Derivatives of-Polycyclic Aromatic Hydrocarbons

A series of oxidized derivatives of nitrophenanthrene and nitrobenz[a]anthracene were synthesized and their mutagenicities in Salmonella typhimurium TA98, TA98NR, TA98/1,8-DNP₆, TA100, and TA100NR were determined. These compounds exhibited markedly different mutagenicities. Orientation of the nitro group is an important structural feature for correlation with mutagenic potency.     

Structural and mechanical properties of Sr+2-doped bismuth manganite thick films

Bismuth strontium manganites Bi_{1 ? x} Sr _x MnO₃ (0.20 ≤ x ≤ 0.50) belonging to the orthorhombic structural family were prepared in furnace using a solid-state reaction technique. Thick films of Bi_{(1 ? x)}Sr _x MnO₃ were prepared by simple screen printing route. X-ray diffraction data suggest that the synthesized materials have an orthorhombic structure. For synthesized materials, texture coefficient (TC), dislocation density (ρ_D), density of crystallites per unit area (ψ), and mechanical properties are reported along with the influence of x on the structure and mechanical properties of BiMnO₃ thick films.     

SHS in mechanoactivated Ni-Al-W blends: Some structural aspects

SHS reaction in mechanically activated Ni-Al-W blends was explored with special emphasis of structural aspects. Dry mechanical activation combined with a wet one was found to improve the strength characteristics of SHS-produced NiAl:W composite by the mechanism of dispersion strengthening.     

Using slurries from flotational coal enrichment in the production of heat insulation on the basis of intershale clay

Heat insulation may be produced from intershale clay and slurries obtained in flotational coal enrichment, without employing traditional materials. The thermal conductivity and density of the insulation produced are 0.20 W/(m °C) and 1200 kg/m³.