Measuring In-Plane Micro-Motion of Micro-Structure Using Optical Flow

Optical flow method is one of the most important methods of analyzing motion images. Optical flow field is used to analyze characteristics of motion objects. According to motion features of micro-electronic mechani-cal system (MEMS) micro-structure, the optical algorithm based on label field and neighborhood optimization is presented to analyze the in-plane micro-motion of micro-structure. Firstly, high speed motion states for each fre-quency segment of micro-structure in cyclic motion are frozen based on stroboscopic principle. Thus a series of dynamic images of micro-structure are obtained. Secondly, the presented optical algorithm is used to analyze the image sequences, and can obtain reliable and precise optical field and reduce computing time. As micro-resonator of testing object, the phase-amplitude curve of micro-structure is derived. Experimental results indicate that the meas-urement precision of the presented algorithm is high, and measurement repeatability reaches 40 nm under the same experiment condition.

TENCEL -A High-Performance Sustainable Cellulose Fiber for the Construction Industry/Composites

Fibers are used in various areas for improving the performance of different materials, commonly used are synthetic fibers and glass fibers. More and more sustainable alternatives are required to reduce energy consumption and the carbon footprint. Traditional natural fibers （like hemp or flax） very often do not fulfill requirements for construction purposes like resistance to elevated temperature or lacking purity. Also mechanical properties of natural fibers are influenced by factors like harvesting, kink bands, climate and growth conditions. Lenzing AG has put a lot of efforts into developing a sustainable fiber overcoming the above mentioned issues. The raw material for TENCEL is wood, which is transformed into a fiber of pure cellulose in an economy friendly process as been proven by a life cycle assessment. The properties of a composite material are highly dependent on parameters like mechanical fiber properties, fiber diameter, quality of fiber dispersion and fiber matrix adhesion. Keeping these properties constant throughout the whole composite part is the factor to success. The diameter as well as the mechanical properties of TENCEL fibers is kept within a very narrow range thanks to the unique manufacturing process. It was shown that the fiber dispersion of TENCEL as well as the fiber matrix adhesion is better than for natural fibers.

Implementation of a Forest Biomass-Based Biofuel Industry： A Canadian Experience

The forest biomass is an abundant renewable resource from which biofuels can be derived. In the Kraft process, the cellulose is extracted from the wood to form the paper pulp while the other organic components, primarily hemicelluloses and lignin, are burnt to produce steam. It is possible to divert part of the hemicelluloses or lignin to produce fuels on site, a mode of operation referred to as the integrated forest biorefinery. Hemicelluloses can be hydrolysed into sugars which in turn are converted into ethanol or butanol, while lignin can be extracted from a residual process stream, the black liquor, by acid precipitation, de-ionized, dried and directly used as a fuel or further processed into value added chemicals. Biorefinery processes have been proposed and analysed by simulation on Aspen Plus. Intensive integration of thermal energy, water and material systems is of paramount importance to the sustainability of the global site; the increased energy load on the utility systems could cause rising dependency of the global site on fossil fuels. To avoid this consequence, a new original energy efficiency analysis and enhancement methodology has been developed and validated on actual Canadian Kraft mills before being applied to the integrated biorefinery and, has produced remarkable results far superior to the current engineering practice. This has led to the concept of the GIFBR （green integrated forest biorefinery）, i.e., an industrial site with zero fossil fuel consumption and reduced GHG （greenhouse gases） emissions vs. the Kraft process and biorefinery plant alone. The GIFBR incorporates a woody biomass gasifier producing syngas as a fuel for the integrated biorefinery and for steam production or sale. It can also include a CHP （combined heat and power） unit driven by steam made available by liberated production capacity from the installed power plant.