Influence of Tree Species, Harvesting Method and Storage on Energy Demand and Wood Chip Quality When Chipping Poplar, Willow and Black Locust

The cultivation of fast-growing wood (e.g., poplar, willow or black locust) in short rotation coppices and agroforestry systems presents an opportunity for producing biomass sustainably in the agricultural sector. Cost-efficient agricultural wood production requires the availability of high-performance machinery and methods with which high-quality wood chips can be produced at low cost. It is known from harvesting short rotation coppices in practice that both the wood chip quality and the performance of the harvesting machinery depend on a variety of factors (e.g., harvesting method, weather conditions, tree species). That is why this study examines in detail the influence of the tree species (different varieties of poplar, willow, black locust) and the wood condition (fresh, stored or dried, frozen) on the specific energy demand for comminution in a stationary drum chipper and on the particle size distribution of the wood chips produced. For all the tree species examined, the chipping of dried as well as frozen stems was connected with a significant increase in the specific energy demand for comminution. An increase of 31% has been measured if poplar stems are chipped in frozen conditions (max. 6.31 kWh t−1). Drying led to an increase of 59% for dried willow stems (max. 6.67 kWh t−1). Drying and frost had also an influence on the size and quality of the wood chips, but no globally significant connection could be established for the examined tree varieties.

Influence of contact-friction interaction at cutting on processing quality

By mathematical modeling it is determined, that when turning in the zone of secondary plastic deformations of the cut layer at increase of the friction coefficient, the length of the chip contact with the front surface of the cutting wedge increases. In this case, significant residual stresses are formed in the surface layer. Keywords cutting, metal, cutting wedge, friction coefficient, chip, quality, stress, residual stresses [email protected]

Label-free on chip quality assessment of cellular blood products using real-time deformability cytometry

Real-time deformability cytometry is a unique tool for quality assessment of therapeutic blood cells utilizing their mechanical properties.

Effect of potassium sources on potato tuber yield and chip quality

ABSTRACT Many potato producers for fry industry changed from the use of potassium chloride to potassium sulfate, as there is a concept that the use of this source improves tuber quality. The aim of this work was to evaluate the effect of these two potassium sources on yield, specific gravity and chip color of potato chipping cultivars. The experiment was carried out on a Dystrophic Red Latosol, in Canoinhas, Brazil, in spring season 2016. Treatments consisted of two potato cultivars, BRSIPR Bel and Atlantic, and two sources of potassium, chloride and sulfate, applied in the furrow at the planting time, in rates based on soil analysis. Experimental design was a randomized complete block in a split-plot arrangement with four replications. Main plots were cultivars and subplots potassium sources. 100 days after planting each sub-plot was evaluated for yield, specific gravity and chip color. There was no significant effect of potassium source on yield components, specific gravity and chip color of BRSIPR Bel and Atlantic.