Methane Pyrolysis for CO2-Free H2 Production: A Green Process to Overcome Renewable Energies Unsteadiness

The Carbon2Chem® project aims to convert exhaust gases from the steel industry into chemicals such as methanol to reduce CO₂ emissions. Here, H₂ is required for the conversion of CO₂ into methanol. Although much effort is put to produce H₂ from renewables, the use of fossil fuels, especially natural gas, seems to be fundamental in the short term. For this reason, the development of clean technologies for the processing of natural gas with a low environmental impact has become a topic of utmost importance. In this context, methane pyrolysis has received special attention to produce CO₂-free H₂.     

TiO2 and ZrO2 supported Ru catalysts for CO mitigation following the water-gas shift reaction

CO oxidation and methanation over Ru-TiO₂ and Ru-ZrO₂ catalysts were investigated for CO removal for applications in proton exchange membrane fuel cells. The catalysts were synthesised by the deposition precipitation method at a pH of 7–7.5 for better interactions between the support and the active Ru metal. Various characterization experiments such as TPR, XPS, FTIR-CO, CO chemisorption and HRTEM were conducted to better understand the physio-chemical properties of Ru on the supports. Both catalysts showed excellent activity for the total oxidation of CO, however, with the addition of H₂, the catalysts activity to CO oxidation decreased significantly. Higher temperatures for the preferential oxidation reaction indicated that the Ru catalysts not only oxidize CO, but hydrogenate it as well. Furthermore, H₂ oxidation was favoured over the catalysts. Hydrogenation of CO over these catalysts gave high CO conversion and selectivity towards CH₄. Both the catalysts showed similar activity across the temperature range screened and gave maximum CO conversions of 99.9% from 240 °C onwards, with 99.9% selectivity towards CH₄. The catalysts also showed good stability in the reaction and the similarities in the catalytic activity of these were attributed to the well-dispersed Ru metal over the supports. The Ru catalysts effectively reduced CO concentrations in the reformate gas to less than 10 ppm, as is required for practical applications.     

Energy for water utilization in China and policy implications for integrated planning

Abstract

Significant energy resources are needed for traditional and nontraditional water utilization in China. Yet the interlinkages between water and energy have not received adequate attention in the country. To address this gap, this article disaggregates and quantifies the magnitude and direction of energy and water flows in China at the national level through Sankey diagrams. Spatial distributions of energy use by different components of the water supply were further mapped at the provincial level to discern regional differences. The results of this study show that the total energy consumption by water abstraction, treatment and distribution, as well as waste treatment and reuse, amounts to 193.5 TWh of electricity, or about 4% of the total national electricity usage. The outcome of this study offers important policy implications for integrated water and energy planning and management and will contribute to achieving the goal of low-energy water utilization in the future.     

Feinstzerkleinerung von CFK-Abfällen und Charakterisierung der Zerkleinerungsprodukte

The comminution of carbon fiber reinforced plastics (CFRP) is a central process step for almost all recycling processes. Size reduction creates a specific surface that serves as a measure in particular of the size reduction success of fines. The article shows the comminution from 1 m edge length in the feed material down to a target product size of less than 100 µm by means of three-stage comminution. The challenges of granulometric characterization of the comminution products and the associated evaluation of the comminution success are specifically addressed.     

Temperature distribution of the straight bar,fixed into a heated plane surface

The authors present the first stage of their theoretical and experimental investigations focused on the fire protection of the steel structures using intumescent paint. In this initial stage, their results concerning the temperature distribution law (the theoretical law is validated by effective meticulously conducted measurements) are described. Their original testing bench destined to perform high‐accuracy monitoring of the temperature distribution along straight bars, having a given α_g angular positioning with respect to the vertical direction is also described. By involving this testing bench in meticulously conducted experiments, the authors obtained both the effective temperature distribution along the bars and also validated the theoretical (exponential) thermal distribution law. By searching experiments, they also validate the m = const. hypothesis with respect to the massive cross‐sectional bars. Among their further goals, one can mention the searching experimental analysis on the validity of the m = const. hypothesis for the tubular cross‐sectional bars, followed by a combined experimental and numerical analysis of the 2‐D and 3‐D (unprotected and protected with intumescent paint layer) structures, as well as the paint layer's thickness optimisation, too.     

Instruction Set Extensions for MPEG-4 Video

This paper describes instruction set extensions for the acceleration of MPEG-4 algorithms on programmable (RISC-) CPUs. MPEG-4 standardizes audio and video compression schemes for a variety of bit rates and scenarios. As MPEG-4 targets a much broader range of different applications than previously defined hybrid video coding standards like H.263 or MPEG-2, it employs a much higher number of different algorithms and coding modes. Therefore, MPEG-4 implementations will require a more software-oriented approach to be efficient. However, the total computational load for an optimized implementation of an MPEG-4 video codec is expected to exceed the performance levels of today's multimedia signal processors, making further hardware acceleration a necessity. For that purpose, we propose a number of instruction set extensions that add function-specific blocks to the data path of a CPU. These dedicated modules are highly adapted to the most computation-intensive processing schemes of MPEG-4, such as DCT, motion compensation, padding, shape coding, or bitstream parsing. The increased functionality of basic instructions results in a significant speed-up over standard RISC instruction sets, thus making MPEG-4 implementations feasible on programmable processor platforms. Possible target architectures include VLIW multimedia processors, MIMD-style multiprocessors, or coprocessor architectures     

Flavonoid concentrations in the inner leaves of head lettuce genotypes

Typical HPLC profiles of phenolics from head lettuce (butter lettuce) genotypes showed quercetin (Qu) compounds Qu 3-O-glucuronide, Qu 3-O-(6-malonylglucoside), an acidic luteolin (Lu) glycoside, chlorogenic acid and chicoric acid as the main compounds in outer and - except the Lu conjugate - inner leaves.The outer leaves of some genotypes additionally contained cyanidin 3-O-(6-malonylglucoside). The generally marginal flavonoid concentrations of the cores of lettuce heads increased between 10-fold and 20-fold during the illumination of opened inner leaves. This indicated the competence of inner leaves of lettuce heads to perform the light-dependent flavonoid biosynthesis. After hydrolysis of flavonoid extracts from 15 head lettuce varieties, Qu concentrations were detected between 19.4 and 152.1 µg/g dry plant material (DW) in inner leaves and from 417.3 to 2482.7 µg/g DW in outer leaves. While the Qu concentrations of the inner leaves of most genotypes, including the commercial varieties, amounted to about 3% of those found in outer leaves, these proportions were 15% and 19% in two genotypes. Two other varieties showed relatively high Qu values of cores in connection with maximum flavonoid levels of outer leaves. It is indicated that such genotypes may be useful in increasing the flavonoid concentrations in the inner leaves of commercial head lettuce varieties by conventional breeding methods.     

Blackberry leaf extract: a multifunctional anti-aging active

Matrix metalloproteinases (MMPs) play a major role in wrinkle formation. Their expression increases with aging and is further enhanced by UV irradiation. Blackberry ( Rubus fruticosus ) leaf extract has been shown to suppress MMP-1, -2 and -9 in cell-free assays. We have now further explored the activity of this extract. The effect on MMP-1 expression at the protein and the mRNA level was investigated using non-irradiated and UVA-irradiated human dermal fibroblasts. The extract showed a dose-dependent reduction of the MMP-1 protein level of both irradiated and non-irradiated cells with an almost complete inhibition at a dosage of 0.1%. MMP-1 mRNA expression of UVA-irradiated cells was decreased after pre-incubation as well as after post-incubation with the extract. Best results were obtained with combined pre- and post-treatment (0.1% extract led to 59% reduction in comparison with the respective control). Moreover, we found that blackberry leaf extract inhibits IL-1α, a cytokine known to induce MMP expression. At a dosage of 0.2% the inhibition was 40% compared with that of the stimulated control. The extract also exhibited a potent radical scavenging activity comparable to that of α-tocopherol as was shown by the ABTS assay. Taken together, these biological activities make blackberry leaf extract a highly efficient multifunctional anti-aging active.     

Some comments on specification tests in nonparametric absolutely regular processes

In this note, several aspects of a recently proposed specification test in nonparametric models driven by an absolutely regular process are discussed. In particular, we give a more detailed asymptotic analysis of tests based on kernel methods under fixed alternatives using a central limit theorem for U-statistics with n-dependent nondegenerate kernel. As a by-product, it is demonstrated that several results regarding the asymptotic distribution or goodness-of-fit tests are incorrectly stated in the literature. Our result also indicates that results on the asymptotic equivalence of nonparametric autoregression and nonparametric regression cannot be used for the asymptotic analysis of goodness-of-fit tests under fixed alternatives.