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Sulfur particles with a conductive polymer coating of poly(3,4-ethylene dioxythiophene) "PEDOT" were prepared by dielectric barrier discharge (DBD) plasma technology under atmospheric conditions (low temperature, ambient pressure). We report a solvent-free, low-cost, low-energy-consumption, safe, and low-risk process to make the material development and production compatible for sustainable technologies. Different coating protocols were developed to produce PEDOT-coated sulfur powders with electrical conductivity in the range of 10-8-10-5 S/cm. The raw sulfur powder (used as the reference) and (low-, optimum-, high-) PEDOT-coated sulfur powders were used to assemble lithium-sulfur (Li-S) cells with a high sulfur loading of ∼4.5 mg/cm2. Long-term galvanostatic cycling at C/10 for 100 cycles showed that the capacity fade was mitigated by ∼30% for the cells containing the optimum-PEDOT-coated sulfur in comparison to the reference Li-S cells with raw sulfur. Rate capability, cyclic voltammetry, and electrochemical impedance analyzes confirmed the improved behavior of the PEDOT-coated sulfur as an active material for lithium-sulfur batteries. The Li-S cells containing optimum-PEDOT-coated sulfur showed the highest reproducibility of their electrochemical properties. A wide variety of bulk and surface characterization methods including conductivity analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and NMR spectroscopy were used to explain the chemical features and the superior behavior of Li-S cells using the optimum-PEDOT-coated sulfur material. Moreover, postmortem [SEM and Brunauer-Emmett-Teller (BET)] analyzes of uncoated and coated samples allowed us to exclude any significant effect at the electrode scale even after 70 cycles.

In this paper we develop a model for the analysis of the impacts of a reform of car taxation in Flanders, one of the three regions in Belgium. We present an empirically based model that can be used to simulate the impacts of a car tax reform on new car purchases in Flanders. In the first part of the paper we estimate a demand model for new cars on the basis of detailed information at market level for cars sold. Next, we use the estimation results to simulate the effects of a reform in car taxation.

During the last 15 years, the official assessment maps in Flanders have improved from a map consisting of only measured data points to a high resolution assessment which covers the complete area and takes into account several types of sources and street canyons. In order to improve this level of detail, multiple steps were taken. First of all, a land use regression model was introduced at an hourly scale at 4 × 4 km2 resolution. Secondly, a Gaussian model was added for both point and line sources, correcting for emission double counting. Finally, a street canyon model was added to the chain, leading to improved resolution in these street canyons. In this work, we will discuss the problems encountered in these years such as how to account for double counting of emissions, how to correct the locations of the simplified road network and how to determine when street canyon calculations must be performed and how we solved them.

Reductive hydrolysis of cellulose to hexitols is a promising technology to valorize cellulose streams. Several catalytic systems have been reported to successfully process commercially available purified cellulose powders according to this technology. Ruthenium-loaded USY zeolites in the presence of minute amounts of HCl previously showed very high hexitol yields. This contribution first investigates into more detail the impact of several cellulose accessibility-related properties like cellulose crystallinity, particle size and degree of polymerization on the conversion rate and hexitol selectivity. Therefore, a series of commercial cellulose samples and several mechano- and chemotreated ones were processed with the Ru/H-USY–HCl catalytic system under standard hot liquid water conditions. The results reveal that the polymerization degree has a large impact on both the conversion rate and selectivity, but its impact fades for DPs lower than 200. From then on, the dominant parameters are the particle size and crystallinity. A second part addresses the influence of cellulose purity. Therefore, organosolv pulps of three lignocellulosic substrates (wheat straw, spruce and birch wood), optionally followed by a bleaching procedure, were processed under the same catalytic circumstances. Here factors like residual lignin content and acid buffer capacity appeared crucial, pointing to the necessity of a dedicated delignification and purification procedure step in order to form the most reactive cellulose feedstock for hexitol production. Complete removal of non-glucosic components is not required since processing of ethanol organosolv birch cellulose and bleached ethanol organosolv wheat straw cellulose, both containing about 6 wt% of lignin and minor contents of ashes and proteins, showed a similar hexitol yield, viz. 34–39%, to that derived from pure microcrystalline cellulose.

In this research work, three different polymers LiPAA, PVDF, and PEO were used as polymeric binders for the sulfur electrodes in Li–S cells. All electrodes had a high sulfur, loading ~4.0 mg per cm2. The coin-cells were characterized by EIS and tested by constant current cycling and cyclic voltammetry using a standard electrolytic solution of LiTFSI in an ether mixture with LiNO3 as additive. The cycled sulfur electrodes were characterized by post-mortem SEM and N2 -sorption and compared to the pristine states. LiPAA-based cells showed the highest reproducibility of the electrochemical performances, the most limited specific capacity fading (at least twice smaller), and the better rate capability compared to PVDF- and PEO-based cells. The electrochemical data agreed with the post-mortem analyses of the different electrodes. The pristine electrodes showed similar morphologies and porosities independent of the polymeric binder used. Dramatic changes were observed for the PEO- and PVDF-based sulfur electrodes, in which a new dense morphology appeared after two and thirty cycles, respectively. Both PEO- and PVDF-based cycled electrodes were prone to delaminate from the current collector. In comparison, the morphology of the LiPAA-based sulfur electrodes remained mostly unchanged even after thirty cycles and no delamination behavior could be observed.

Protein adsorption on inorganic surfaces involves a complex mechanism which could be controlled by surface functionalization methods. A dry surface functionalization method for powders could be beneficial as compared to wet-chemical methods, since aspects like suspension preparation and subsequent drying can be avoided. This paper focuses on atmospheric pressure plasma technology for surface activation of hydroxyapatite powder as a carrier in oral administration applications, aiming at increasing the loading capacity of proteins. Hydroxyapatite powder is treated in N2 and N2H2 atmospheric plasma processes within a static and a dynamic reactor. The influence of plasma activation on the protein adsorption isotherms, powder characteristics: particle morphology, specific surface area, and particle size distribution; have been discussed. The nature and amount of functional groups are studied by zeta potential measurements, thermogravimetric analysis, and titration analysis. Atmospheric plasma treatment increases the protein loading up to 37% when hydroxyapatite powder is treated in pure N2 plasma whereas that of powder activated using N2H2 plasma increased by 13%. The increased protein loading can be attributed to the creation of nitrogen and oxygen containing moieties which cause an increased hydrophilicity after plasma treatment.

Advances in the synthesis of porous microspheres and in their functionalization are increasing the interest in applications of alumina. This paper deals with coatings plasma deposited from 3-aminopropyltriethoxysilane by means of dielectric barrier discharges on alumina porous microspheres, shaped by a vibrational droplet coagulation technique. Aims of the work are the functionalization of the particles with active amino groups, as well as the evaluation of their surface coverage and of the penetration of the coatings into their pores. A multi-diagnostic approach was used for the chemical/morphological characterization of the particles. It was found that 5 min exposure to plasma discharges promotes the deposition of homogeneous coatings onto the microspheres and within their pores, down to 1 μm.

This paper quantifies the effect of a number of input parameters on the emission levels of road transport emissions calculated by means of a bottom-up methodology. The input parameters considered cover small diesel cars, calculation of additional fuel consumption due to the use of mobile air conditioning in passenger cars and light commercial vehicles, fine-tuning of trip lengths and definition of road types for Belgium in 2010. The effect is significant for CO2, and even more pronounced for other pollutants such as NOx, PM2.5, and VOCs.