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bio- refinery-based bark processing. Keywords: biorefinery; flavanyl units; hardwood bark; inter- flavanoid bonds; linear diarylheptanoids; oregonin; tannins; proantocyanidins; sorbents. Introduction Currently only 6=109 t of the 170=109 t of biomass pro- duced annually by photosynthesis are utilised and only 3% of this is in the non-food application (Kamm and Kamm 2004). However, increased R&D activities are directed toward a sustainable economy based on renewable sources such as plant biomass (Cherubini 2010). In this context, tree barks have a high potential to

:water extracts are higher in A. subcordata (16.9%) and the EtOH:water (8:2, v/v) extract was higher in P. fraxinifolia and P. persica. Water extract was highest in P. persica . Alnus subcordata and G. caspica had the highest and the lowest total extractives yields (21.8% vs. 13.8%), respectively. In comparison with other solvents, the acetone:water (9:1, v/v) resulted in the highest total yields. These data are in the range of hardwood bark extractives contents described in the literature ( Makino et al. 2009 ). Table 1: Chemical composition of the bark extractives

. Assoc. 77—90. Zur Struktur des Lignins der Rinde von Laub- und Nadelhölzern*) Von Arne Andersson, Magnus Erickson, Hans Fridh und Gerhard E. Miksche Institutionen for organisk kemi, Chalmers Tekniska Högskola och Göteborgs Universitet, Fack, 8-402 20 Göteborg 5, Schweden Schlüsselwörter (Sachgebiete) Nadelhölzer Laubhölzer Rinde Lignin Oxydativer Abbau Aromatische Carbonsäuren Phenolsäuren Ligninbildung Picea abies ^ Taxus baccata Betula verrucosa Fraxinus excelsior Vitis vinifera Keywords Softwoods Hardwoods Bark Lignin Oxidative degradation Aryl carboxylic acids

, Fack, 8-402 20 Göteborg 5, Schweden Schlüsselwörter (Sachgebiete) Nadelhölzer Laubhölzer Rinde Lignin Oxydativer Abbau Aromatische Carbonsäuren Phenolsäuren Ligninbildung Picea abies ^ Taxus baccata Betula verrucosa Fraxinus excelsior Vitis vinifera Keywords Softwoods Hardwoods Bark Lignin Oxidative degradation Aryl carboxylic acids Phenolic acids Formation of lignin Zur Struktur des Lignins der Rinde von Laub- und Nadelhölzern Zusammenfassung Die Sulfatlignine des Holzes und der Rinde (Borke und Bast) zweier Nadelhölzer (Picea abies [L.] Karst, und Taxus baccata L

reduced gradually with the increased content of bark. Earlier, researchers also reported high kappa number i. e. 64.6 for eucalyptus bark and 28.3 for mixed hardwood bark as compared to 15.5 for eucalyptus chips and 16.9 for mixed hardwood chips using similar pulping conditions applying 18.8 % effective alkali (Santos and Hart 2016 ). Effect of different proportion of bark on unscreened and screened pulp yield, kappa number and brightness of pulp while using similar AA during pulping are shown in Figure 1 . Figure 1 Effect of different proportions of bark on pulp

Hardwoods (bark) 32–45 b 40–50 b <20 b 5–10 3 Softwoods (wood) 66–72 25–30 b 0.2–0.6 b 2–9 3 Softwoods (bark) 30–48 40–55 b <20 b 2–25 3 a (1) Bertaud and Holmbom (2004 ), (2) Björk and Rasmuson (1995 ), (3) Harkin et al. (1971 ). b Based on extractive-free material. The present study was undertaken to provide sorption isotherm, its hysteresis, and the moisture diffusivity of bark of beech and spruce in comparison of these properties with those of wood. The expectation is that the collected data will contribute to a more efficient utilization of barks in various

. (1991) A review of assessing the accuracy of clas- sifications of remotely sensed data. Rem. Sens. Environ. 37: 35–46. Dong, P.L. (2002) Lacunarity analysis of spaceborn radar image texture for rock unit discrimination. PhD thesis, Department of Geology, University of New Brunswick, Canada. Einspahr, D.W., Harder, M. (1975) Hardwood bark properties important to the manufacture of fiber products. IPC Techn. Pap. Ser. 11:11–28. Ghosh, M.N., Sharma, D. (1963) Power of Tukey’s test for non- additivity. J. Roy. Statist. Soc. 25B:213–219. Haralick, R.M., Shanmugam, K

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, acidic compost, ground hardwood bark, old Christmas-trees, pine bark, or pine needles may help acidify soil over a longer period. Once es- tablished, plants that produce acidic litter can permanently acidify soils at least locally. Urban soils, especially fi ll soil containing demolition debris, generally contains a lot of concrete, which is alkaline. The wear of sidewalks, streets, curbs, and other concrete structures falls out as concrete dust that fi nds its way even into native soils. It is necessary, therefore, to give thought to the use of acidifying soil

same components; (2) the macromolecular compounds existing in the vegetable bio- mass incorporate biosynthesis energy, and their conversion to useful products seems to be consid- ered; (3) the complex and total processing technology may be modulated depending on the chemical composition of the vegetable source, as well as on the utilization of the obtained chem- ical compounds. The possibilities of complex processing of soft- and hardwood bark, agricul- tural wastes, and some energetic cultures of Helianthus tuberosus and Asclepias syriaca are exemplified. In order

decreased in the younger xylem and in the phloem. The primary xylem yielded only vanillin. Investigations of bark lignins from several softwoods (Picea abies, Taxus baccata) and hardwoods (Betula verrucosa, Fraxinus excelsior, Vitis vinifera) showed that the softwood bark lignins are typical G-lignins with increased amounts of Η-units as compared to the corresponding wood lignins. The hardwood bark lignins are GS- lignins with higher proportions of G-units than the wood lignins (Anderson et al. 1973) (-» 9.2.4.). A very important aspect of lignin heterogeneity was

in Wood