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The development of biofuels has been considered as an important countermeasure to abate anthropogenic CO2 emissions, suppress deteriorated atmospheric greenhouse effect, and mitigate global warming. To produce biofuels from biomass, thermochemical conversion processes are considered as the most efficient routes wherein torrefaction has the lowest global warming potential. Combustion is the easiest way to consume biomass, which can be burned alone or co-fired with coal to generate heat and power. However, solid biomass fuels are not commonly applied in the industry due to their characteristics of hygroscopic nature and high moisture content, low bulk density and calorific value, poor grindability, low compositional homogeneity, and lower resistance against biological degradation. In recently developing biomass conversion technologies, torrefaction has attracted much attention since it can effectively upgrade solid biomass and produce coal-like fuel. Torrefaction is categorized into dry and wet torrefaction; the former can further be split into non-oxidative and oxidative torrefaction. Despite numerous methods developed, non-oxidative torrefaction, normally termed torrefaction, has a higher potential for practical applications and commercialization when compared to other methods. To provide a comprehensive review of the progress in biomass torrefaction technologies, this study aims to perform an in-depth literature survey of torrefaction principles, processes, systems, and to identify a current trend in practical torrefaction development and environmental performance. Moreover, the encountered challenges and perspectives from torrefaction development are underlined. This state-of-the-art review is conducive to the production and applications of biochar for resource utilization and environmental sustainability. To date, several kinds of reactors have been developed, while there is still no obviously preferred one as they simultaneously have pros and cons. Integrating t

We review the recent progress achieved by our international collaboration on novel imaging techniques based on high-brightness and highly coherent synchrotron sources. After outlining the background, we will discuss the technical progress of recent years. Then, we will exemplify the applications with a number of cases in materials science and life sciences, in particular neurobiology. New results on metal electrodeposition will be used to practically illustrate the impact of the techniques in this important technological area and in general its potential for materials research. Finally, we will briefly comment on the foreseeable technical improvements and on their positive consequences.

We review the recent progress achieved by our international collaboration on novel imaging techniques based on high-brightness and highly coherent synchrotron sources. After outlining the background, we will discuss the technical progress of recent years. Then, we will exemplify the applications with a number of cases in materials science and life sciences, in particular neurobiology. New results on metal electrodeposition will be used to practically illustrate the impact of the techniques in this important technological area and in general its potential for materials research. Finally, we will briefly comment on the foreseeable technical improvements and on their positive consequences.

Magnetic anisotropy, magnetization reversal and the magnetooptic Kerr effect in CoxMnyGez have been studied over a range of compositions between 0 and 50 at.% of Ge and between 1 and 3 in the Co to Mn atomic ratio, including the Heusler alloy Co2MnGe. A strong quadratic magnetooptic Kerr effect has been observed within a narrow region of composition centered around the Co to Mn atomic ratio of 2, which has been used to probe and quantify the magnetic anisotropy and magnetization reversal of the system. The anisotropy is sixfold with a weak uniaxial component, and it exhibits sensitive dependence on composition, especially on the atomic ratio between Co and Mn. The magnetization reversal process is consistent with the single-domain Stoner-Wohlfarth model., QC 20110415

With the broad acceptance of the ATM technology, development of the related host-interface has been actively carried out. We have built an ATM/TAXI network interface card for the ISA-bus based Personal Computer (PC) host. Two FPGAs that support the TAXI interface and the ATM/AAL5 functions are implemented for such a high speed communication interface. Based on this prototype, we measure individual communication protocol stack throughputs and compare them with those of the Ethernet network. We then derive a design guideline for improving the system throughput of an ATM PC host.