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Poly(ethylene terephthalate) (PET) materials with different molecular weights were isothermally crystallized from melt by systematically varying the temperature and duration of the treatment performed in the differential scanning calorimeter (DSC). Multiple endotherm peaks were observed on the subsequent heating thermograms that were separated from each other on the basis of their melting temperature versus crystallization temperature and melting temperature versus crystallinity function. By this new approach five sub-peak sets were identified and then comprehensively characterised. Wide-Angle X-Ray Diffraction (WAXD) analyses revealed that the identified sub-peak sets do not differ in crystalline forms. By analysing the crystallinity and the melting temperature of the sub-peak sets as a function of crystallization time, crystallization temperature and intrinsic viscosity, it was concluded that below the crystallization temperature of 460 K the sub-peak sets that were formed during primary or secondary crystallization transform partially or completely to a third sub-peak set during the heating run of the measurement, while above this temperature, the sub-peak set formed during primary crystallization gradually transforms to a more stable structure, with higher melting temperature. These formations and transformations are described with mathematically defined parameters as well. [ABSTRACT FROM AUTHOR]

• This article focuses on simultaneous mechanical activation and CO 2 capture and storage on Linz-Donawitz steel slag. • The primary objective of the experiments was to observe the role H 2 O in the reactions. • The experiment showed that 3 times as much CO 2 can be sequestered in wet conditions than in dry conditions. • Compared to similar research, mechanical activation can greatly reduce the time required for carbonate reactions. Mineral carbonation, a process of carbon-dioxide (CO 2) captured from the atmosphere or flue gases, is a way to sequestrate CO 2 safely and permanently. In this technology, CO 2 is chemically reacted with calcium, magnesium, sodium, and iron-containing materials. The procedure is analogous to natural weathering processes, to form thermodynamically stable and environmentally harmless carbonate minerals. Our research was focused on simultaneous mechanical activation and CO 2 capture and storage (CCS) on Linz-Donawitz steel slag dominantly composed of Ca-silicate and oxide phases. The experiments were carried out in a planetary ball mill under 5 bar CO 2 pressure in dry and wet (deionized H 2 O) conditions. The primary objective of the experiments was to observe the role of H 2 O in the reactions. The presence of H 2 O in the system leads to a finer particle size distribution but, at the same time, reduces the number of active sites·H 2 O also acts as a carbonate reaction promoter, it is expected to initialize silicate (Windt et al. 2010) surface protonation and enhancing Ca leaching. The latter of the two processes was predominant so that in wet condition (0,246 kgCO 2 /kg), almost three times as much calcite is produced as in dry condition (0,083 kgCO 2 /kg). The combination of nano milling and wet media carbonation is a promising process to reduce energy requirement through increasing the reaction rate and promotes the use of Ca-silicate wastes otherwise underperforming in CCS. [ABSTRACT FROM AUTHOR]

Maghemite particles were synthesized by using a combined combustion method and sonochemical step. Maghemite was used as carrier to prepare supported Pt and Pd catalysts after deposition via a sonochemical step. The catalysts were immediately ready to be used (metals were catalytically active) for the 2,4-dinitrotoluene hydrogenation to produce 2,4-toluenediamine. The most active catalysts were the Pd/maghemite and bimetallic Pd-Pt/maghemite. The catalysts were easily separable after reaction due to their magnetic properties. [Display omitted] • Application of maghemite catalyst supports. • Simplified, efficient and fast sonochemical catalyst preparation method. • Magnetic separable palladium catalysts. • High catalytic activity in hydrogenation of dinitrotoluene. [ABSTRACT FROM AUTHOR]

• Nano-Ag particles are reduced by new, efficient and reproducible chemical processing. • 3 wt% Ag nanoparticles were reduced on the surface on Ti powders. • Porous sintered samples with 80% density has been created. • The Ti powder with Ag coating and sintered samples demonstrated strong antibacterial ability. • The mechanical and antibacterial properties of the sintered samples are investigated. In this work, silver (Ag) was reduced in nano-size on the surface on titanium (Ti) powder by chemical reduction method, which is a new, efficient and reproducible method. The amount of the Ag nanoparticles was at least 1.9 at. % in the Ti-Ag implant material and the typical size of these nanoparticles was under 50 nm. Owing to the powder metallurgy methods porous structure can be created and the relative density of the cold-pressed and sintered samples was 81 ± 1%. The mechanical properties were as follows: HV 0.01 (363 ± 78), ultimate compressive true stress (470 ± 4 MPa) and Yield strength (277 ± 12 MPa). After the sintering process, TiAg and Ti 2 Ag phases were formed owing to the diffusion. The antibacterial features of Ag coated Ti powder, the sintered Ti-Ag alloy and its etched form were investigated. The strong antibacterial property was observed in the case of Ag coated Ti powder. It also turned out that E. coli bacteria in close contact of these Ti-Ag alloy surfaces cannot survive and the observed antibacterial properties may not be associated with the release of water soluble component from the alloy. Due to this local antibacterial feature of Ti-Ag alloys, they can be a good candidate for antibacterial implant material with potential biocompatibility. [ABSTRACT FROM AUTHOR]