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In this study, the effect of recycling the non-condensable gases (NCG) in the catalytic pyrolysis of hybrid poplar using FCC catalyst was investigated. A 50mm bench scale fluidized bed reactor at 475°C with a weight hourly space velocity (WHSV) of 2h(-1) and a gas recycling capability was used for the studies. Model fluidizing gas mixtures of CO/N(2), CO(2)/N(2), CO/CO(2)/N(2) and H(2)/N(2) were used to determine their independent effects. Recycling of the NCG in the process was found to potentially increase the liquid yield and decrease char/coke yield. The model fluidizing gases increased the liquid yield and the CO(2)/N(2) fluidizing gas had the lowest char/coke yield. The (13)C-NMR analysis showed that recycling of NCG increases the aromatic fractions and decreases the methoxy, carboxylic and sugar fractions. Recycling of NCG increased the higher heating value and the pH of the bio-oil as well as decreased the viscosity and density.

Patient-specific ridge filters provide a passive means to modulate proton energy to obtain a conformal dose. Here we describe a new framework for optimization of filter design and spot maps to meet the unique demands of ultrahigh-dose-rate (FLASH) radiation therapy. We demonstrate an integrated physical optimization Intensity-modulated proton therapy (IMPT) (IPO-IMPT) approach for optimization of dose, dose-averaged dose rate (DADR), and dose-averaged linear energy transfer (LETd).We developed an inverse planning software to design patient-specific ridge filters that spread the Bragg peak from a fixed-energy, 250-MeV beam to a proximal beam-specific planning target volume. The software defines patient-specific ridge filter pin shapes and uses a Monte Carlo calculation engine, based on Geant4, to provide dose and LET influence matrices. Plan optimization, using matRAD, accommodates the IPO-IMPT objective function considering dose, dose rate, and LET simultaneously with minimum monitor unit constraints. The framework enables design of both regularly spaced and sparse-optimized ridge filters, from which some pins are omitted to allow faster delivery and selective LET optimization. To demonstrate the framework, we designed ridge filters for 3 example patients with lung cancer and optimized the plans using IPO-IMPT.The IPO-IMPT framework selectively spared the organs at risk by reducing LET and increasing dose rate, relative to IMPT planning. Sparse-optimized ridge filters were superior to regularly spaced ridge filters in dose rate. Depending on which parameter is prioritized, volume distributions and histograms for dose, DADR, and LETd, using evaluation structures specific to heart, lung, and esophagus, show high levels of FLASH dose-rate coverage and/or reduced LETd, while maintaining dose coverage within the beam specific planning target volume.This proof-of-concept study demonstrates the feasibility of using an IPO-IMPT framework to accomplish proton FLASH stereotactic body proton therapy, accounting for dose, DADR, and LETd simultaneously.

Abstract Global irradiance spectra vary with location, different viewing angles and times of day, depending on the fraction of direct and diffuse irradiance. Owing to big differences in spectral responses, PV module technologies might therefore show a differing behaviour with varying orientation and tilt angles. The purpose of this work is to verify the thesis, that thin film modules are – due to their spectral response – more suitable for horizontal orientation than crystalline. Diffuse irradiation (except from circumsolar radiation) can be captured best by a horizontal surface and consists to a greater fraction of short wavelengths than direct irradiation. At the same time thin film modules primarily absorb photons of short wavelengths and could therefore be better suited for horizontal application. Based on the semi-empirical spectral model Sedes2 and quantum efficiency data, a model has been developed to analyse differences in optimum orientation of several PV module technologies. In a first step, hourly global irradiance spectra are generated from a 1 year dataset of hourly climate data derived from long-term averages by the Meteonorm database for two sites in different climes. Based on this, average photocurrent densities are computed for each technology and for a matrix of different orientation and tilt angles using quantum efficiency data. Normalised to their maximum, the photocurrent densities are compared between the technologies. The results we obtained show, that for each site the maximum relative photocurrent densities are located at about the same orientation for all technologies, i.e. the optimum orientation is the same. At horizontal orientation, thin film modules show a slightly higher value of normalised average photocurrent densities than monocrystalline modules. Yet, for a whole year this advantage lies below 1% for both sites.

Abstract Over the last decades, electricity markets across OECD countries have been subjected to profound structural changes with far-reaching implications on the economy and the environment. This paper investigates the effect of restructuring – changes in entry regulations, the degree of vertical integration and ownership structure – on GHG emissions. The findings show that competition policies – particularly reducing the degree of vertical integration and increasing privatization – correlate negatively with emission intensity. However, the environmental effect of reducing market entry barriers is generally insignificant. Integration of competition and stringent environmental policies are required to reduce GHG emissions and improve environmental quality.

Although the integrated energy and environmental planning processes of cities and territories with more than 50,000 inhabitants differ, previous studies suggest that long-term, model-based energy planning processes have a common scheme that can also be used as a framework for reviewing the methods and the tools that are used in the integrated energy planning of these cities and territories. This paper first presents a generic integrated energy planning procedure in which the planning activities are divided into four main phases. Second, the methods and the tools that are used for these diverse planning tasks are mapped to the suggested generic planning procedure tasks. Finally, the combined use of these methods and tools in the scope of integrated energy planning are briefly discussed from a mapping point of view.

The non-Antarctic Notothenioidei families, Bovichtidae, Pseudaphritidae and Eleginopsidae, diverged early from the main notothenioid lineage. They are important in clarifying the early evolutionary processes that triggered notothenioid evolution in the Antarctic. The early-diverged group represents 8% of all notothenioid species and never established themselves on the Antarctic shelf. Most attention has been paid to the Antarctic notothenioids and their limited physiological tolerance to climate change and increased temperatures. In this review, we discuss key life history traits that are characteristic of the non-Antarctic early-diverged notothenioid taxa as well as the genetic resources and population differentiation information available for this group. We emphasise the population fitness and dynamics of these species and indicate how resource management and conservation of the group can be strengthened through an integrative approach. Both Antarctic waters and the non-Antarctic regions face rapid temperature rises combined with strong anthropogenic exploitation. While it is expected that early-diverged notothenioid species may have physiological advantages over high Antarctic species, it is difficult to predict how climate changes might alter the geographic range, behaviour, phenology and ultimately genetic variability of these species. It is possible, however, that their high degree of endemism and dependence on local environmental specificities to complete their life cycles might enhance their vulnerability.

Abstract A new energy-transfer pair is presented consisting of fluorescamine as the donor and fluorescein as the acceptor. The system has been investigated with binding of histone H5 to nucleosomal particles. Histone H5 has been labeled as its free N-terminus with fluorescamine while fluorescein is bound via a disulfide bridge to the cysteine of the core histone H3. The properties of this system are described. The distance between the chromophores is estimated and found to be consistent with the known nucleosome geometry.

The requirements for rechargeable batteries place high demands on the electrodes. Efficient storage means accommodating both ions and electrons, not only in substantial amounts, but also with substantial velocities. The materials’ space could be largely extended by decoupling the roles of ions and electrons such that transport and accommodation of ions take place in one phase of a composite, and transport and accommodation of electrons in the other phase. Here we discuss this synergistic concept being equally applicable for positive and negative electrodes along with examples from the literature for Li-based and Ag-based cells. Not only does the concept have the potential to mitigate the trade-off between power density and energy density, it also enables a generalized view of bulk and interfacial storage as necessary for nanocrystals. It furthermore allows for testable predictions of heterogeneous storage in passivation layers, dependence of transfer resistance on the state of charge, or heterogeneous storage of hydrogen at appropriate contacts. We also present an outlook on constructing artificial mixed-conductor electrodes that have the potential to achieve both high energy density and high power density. Electrochemical storage is typically accompanied by simultaneous accommodation of ions and electrons. Here the authors discuss a concept of decoupling electron and ion storage and present their perspectives of constructing artificial mixed conductor electrodes to enhance storage ability.