Mai, Carsten

[["dc.bibliographiccitation.firstpage","343"],["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","WOOD RESEARCH"],["dc.bibliographiccitation.lastpage","350"],["dc.bibliographiccitation.volume","58"],["dc.contributor.author","Kielmann, Bodo Caspar"],["dc.contributor.author","Militz, Holger"],["dc.contributor.author","Mai, Carsten"],["dc.contributor.author","Adamopoulos, Stergios"],["dc.date.accessioned","2018-11-07T09:29:35Z"],["dc.date.available","2018-11-07T09:29:35Z"],["dc.date.issued","2013"],["dc.description.abstract","Ash, beech and maple wood was modified with aqueous solutions of methylated N-methylol melamine (NMM) and a metal-complex dye (BS) consisting of 10, 20, and 30 % NMM and 5 % BS. Static bending strength and stiffness, impact bending strength and hardness were examined to evaluate the suitability of modified wood for structural uses. The combined NMM-BS modification resulted in significant higher dynamic (MOEdyn) and static (MOE) moduli of elasticity for all species. Beech and maple exhibited enhanced static bending strength (MOR), while that of ash was unchanged. The higher stiffness and strength of NMM-BS modified wood is attributed to its higher wood density and lower EMC and to the stiff character of NMM resin incorporated in the wood matrix. Impact bending strength decreased substantially after modification as a result of reduced pliability of treated wood. Brinell hardness significantly increased with the weight percent gain (WPG) due to modification, and, unlike the other properties, it was positively correlated with the WPG."],["dc.description.sponsorship","AIF through the ZIM cooperation program [KF 2454601GZ9]"],["dc.identifier.isi","000325835300002"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/31074"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Slovak Forest Products Research Inst"],["dc.relation.issn","1336-4561"],["dc.title","STRENGTH CHANGES IN ASH, BEECH AND MAPLE WOOD MODIFIED WITH A N-METHYLOL MELAMINE COMPOUND AND A METAL-COMPLEX DYE"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","BioResources"],["dc.bibliographiccitation.volume","13"],["dc.contributor.author","Hosseinpourpia, Reza"],["dc.contributor.author","Adamopoulos, Stergios"],["dc.contributor.author","Mai, Carsten"],["dc.date.accessioned","2020-12-10T18:42:43Z"],["dc.date.available","2020-12-10T18:42:43Z"],["dc.date.issued","2017"],["dc.identifier.doi","10.15376/biores.13.1.331-345"],["dc.identifier.eissn","1930-2126"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/78054"],["dc.notes.intern","DOI Import GROB-354"],["dc.title","Effects of Acid Pre-Treatments on the Swelling and Vapor Sorption of Thermally Modified Scots Pine (Pinus sylvestris L.) Wood"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","123"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Wood Science and Technology"],["dc.bibliographiccitation.lastpage","136"],["dc.bibliographiccitation.volume","48"],["dc.contributor.author","Kielmann, Bodo Caspar"],["dc.contributor.author","Adamopoulos, Stergios"],["dc.contributor.author","Militz, Holger"],["dc.contributor.author","Koch, Gerald"],["dc.contributor.author","Mai, Carsten"],["dc.date.accessioned","2018-11-07T09:46:44Z"],["dc.date.available","2018-11-07T09:46:44Z"],["dc.date.issued","2014"],["dc.description.abstract","This study evaluated the combined modification and staining of ash, beech and maple wood with a low molecular weight N-methylol melamine compound (NMM) and a metal-complex dye. Wood samples were treated with aqueous solutions of 10, 20 and 30 wt% NMM and 5 wt% of the dye. The treatment caused the fixation of the water-soluble dye by the NMM resin. Vacuum pressure impregnation of unsealed wood blocks did not result in different solution uptake and weight percent gain after curing among the three species, but sealing of the surfaces of the wood blocks to allow penetration only into one direction revealed easiest penetrability of beech followed by maple and ash. UV micro-spectrophotometry and light microscopy indicated that NMM was partly deposited in the cell wall and partly in the lumens. Penetration of the metal-complex dye was shown by means of X-ray micro-analysis (SEM-EDX). The study shows that a combined resin modification and staining of the three wood species tested is possible and that NMM causes fixation of the water-soluble dye."],["dc.identifier.doi","10.1007/s00226-013-0595-y"],["dc.identifier.isi","000330626100012"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/34949"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","1432-5225"],["dc.relation.issn","0043-7719"],["dc.title","Modification of three hardwoods with an N-methylol melamine compound and a metal-complex dye"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","110"],["dc.bibliographiccitation.journal","International Biodeterioration & Biodegradation"],["dc.bibliographiccitation.lastpage","114"],["dc.bibliographiccitation.volume","89"],["dc.contributor.author","Kielmann, Bodo Caspar"],["dc.contributor.author","Adamopoulos, Stergios"],["dc.contributor.author","Militz, Holger"],["dc.contributor.author","Mai, Carsten"],["dc.date.accessioned","2018-11-07T09:42:07Z"],["dc.date.available","2018-11-07T09:42:07Z"],["dc.date.issued","2014"],["dc.description.abstract","This study evaluated the decay resistance of ash (Fraxinus excelsior L), beech (Fagus sylvatica L), and maple (Acer platanoides L) wood impregnated by a full cell process with N-methylol melamine (NMM) and combined NMM-metal complex dye (NMM-BS) in aqueous solutions. Basidiomycete decay testing involved incubation with Coniophora puteana (brown rot) and Trametes versicolor (white rot) according to a modified EN 113 (1996) standard, while for the soft rot fungal resistance was evaluated following the standard ENv 807 (2001). NMM and NMM-BS modifications at a WPG range of 7-11% provided decay protection against brown rot resulting in a mass loss less than the required limit (3%). The NMM and NMM-BS modified wood showed increased resistance to white rot decay; however, a higher WPG is needed to prohibit attack from this hardwood specific fungus. The metal-complex dye alone revealed biocidal effects against basidiomycetes. An increased WPG in NMM or NMM-BS had a positive impact against soft rot decay and the lowest mass losses after 32 weeks of exposure were obtained with NMM modification at about 18-21% WPG. NMM modification at this WPG range, however, was not sufficient to protect the wood from soft rot decay. The wood of beech and maple showed slightly higher resistance to all decay types than ash, probably due to the poorer degree of modification of the latter. (C) 2014 Elsevier Ltd. All rights reserved."],["dc.description.sponsorship","AIF through the ZIM cooperation program [KF 2454601GZ9]"],["dc.identifier.doi","10.1016/j.ibiod.2014.01.011"],["dc.identifier.isi","000333782100016"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/33883"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Elsevier Sci Ltd"],["dc.relation.issn","1879-0208"],["dc.relation.issn","0964-8305"],["dc.title","Decay resistance of ash, beech and maple wood modified with N-methylol melamine and a metal complex dye"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","161"],["dc.bibliographiccitation.journal","Polymer Degradation and Stability"],["dc.bibliographiccitation.lastpage","168"],["dc.bibliographiccitation.volume","138"],["dc.contributor.author","Hosseinpourpia, Reza"],["dc.contributor.author","Adamopoulos, Stergios"],["dc.contributor.author","Holstein, Nonna"],["dc.contributor.author","Mai, Carsten"],["dc.date.accessioned","2018-11-07T10:25:28Z"],["dc.date.available","2018-11-07T10:25:28Z"],["dc.date.issued","2017"],["dc.description.abstract","This study investigates the effect of proton acid pre-treatment and subsequent thermal modification at relatively low temperatures (up to 180 degrees C) on wood with respect to dimensional stability and water vapour sorption properties. The effects are compared to those of solely thermally-modified wood at higher temperatures (up to 250 degrees C). Scots pine sapwood (P. sylvestris L) was impregnated with a proton acid or demineralised water, and subsequently, thermally modified to various mass losses (ML). Acid pretreatment and thermal modification improved the dimensional stability and reduced the equilibrium moisture content (EMC) until certain ML. Excess surface work (ESW) obtained from vapour sorption studies indicated that, at comparable ML, the acid pre-treatment reduced the available sorption sites as compared to sole thermal treatment. Samples pre-treated with acid also showed stronger decreasing courses of EMC- and ESW-ratios than sole thermally modified ones. This was attributed to degradation of amorphous wood polymers and a stiffer matrix due to cross-linking of the cell wall polymers as a consequence of acid pre-treatment. Electron spin resonance (ESR) analysis indicated that acid pretreatment did not enhance the concentration of phenoxy radicals, whereas thermally modified wood showed a considerably higher concentration of phenoxy radicals, suggesting that high radical density cannot be used as an indicator for high matrix stiffness. (C) 2017 Elsevier Ltd. All rights reserved."],["dc.identifier.doi","10.1016/j.polymdegradstab.2017.03.009"],["dc.identifier.isi","000400222500018"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/42863"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","PUB_WoS_Import"],["dc.publisher","Elsevier Sci Ltd"],["dc.relation.issn","1873-2321"],["dc.relation.issn","0141-3910"],["dc.title","Dynamic vapour sorption and water-related properties of thermally modified Scots pine (Pinus sylvestris L.) wood pre-treated with proton acid"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","41290"],["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","Journal of Applied Polymer Science"],["dc.bibliographiccitation.volume","132"],["dc.contributor.author","Hosseinpourpia, Reza"],["dc.contributor.author","Adamopoulos, Stergios"],["dc.contributor.author","Mai, Carsten"],["dc.date.accessioned","2018-11-07T10:02:10Z"],["dc.date.available","2018-11-07T10:02:10Z"],["dc.date.issued","2015"],["dc.description.abstract","The main objective of this study was to assess the effect of two amino resins, N-methylol melamine (NMM) and 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU), on the intrafiber and interfiber strengths and water absorption of two types of waste paper categories, office paper (OP), and old corrugated containers (OCCs). The tensile strength of individual fibers measured at zero span was reduced by increases in the resin concentrations. The dry tensile strengths of the recovered handsheets measured at a finite span were enhanced with increases in the weight percentage gain of the resins. The increasing of the resin concentration also significantly improved the intrabonding of the OP and OCCs in moist measuring conditions. The water absorption of the handsheets considerably decreased at the higher concentration of the thermosetting resins, especially with NMM. The results are promising for the use of NMM- and DMDHEU-treated recovered fibers as an alternative fiber resource for the production of laminated paper and also for the use of DMDHEU as a new N-methylol compound for laminated paper. (c) 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41290."],["dc.identifier.doi","10.1002/app.41290"],["dc.identifier.isi","000344006100011"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/38174"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Wiley-blackwell"],["dc.relation.issn","1097-4628"],["dc.relation.issn","0021-8995"],["dc.title","Tensile Strength of Handsheets from Recovered Fibers Treated with N-Methylol Melamine and 1,3-Dimethylol-4,5-dihydroxyethyleneurea"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","897"],["dc.bibliographiccitation.issue","6"],["dc.bibliographiccitation.journal","European Journal of Wood and Wood Products"],["dc.bibliographiccitation.lastpage","901"],["dc.bibliographiccitation.volume","70"],["dc.contributor.author","Adamopoulos, Stergios"],["dc.contributor.author","Bastani, Alireza"],["dc.contributor.author","Gascon-Garrido, Patricia"],["dc.contributor.author","Militz, Holger"],["dc.contributor.author","Mai, Carsten"],["dc.date.accessioned","2018-11-07T09:04:15Z"],["dc.date.available","2018-11-07T09:04:15Z"],["dc.date.issued","2012"],["dc.description.abstract","Untreated (controls) and phenol-formaldehyde (PF)-modified beech wood (10 and 25 % solid content) were glued with phenol resorcinol formaldehyde (PRF) and polyvinyl acetate (PVAc). Shear strength of PRF-bonded specimens was higher than that of PVAc-bonded ones under dry and wet conditions irrespective of the pre-treatment. Under dry conditions, only PVAc-bonded specimens exhibited reduction in shear strength due to PF-modification with 25 % PF concentration as compared to the controls. PF treated wood provided inferior bonding under wet conditions with the exception of 25 % PF concentration specimens glued with PRF adhesive. Modification with PF resulted in a decrease of adhesive penetration into the porous network of interconnected cells, especially at 25 % PF concentration."],["dc.identifier.doi","10.1007/s00107-012-0620-0"],["dc.identifier.isi","000309868500017"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/8785"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/25075"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","0018-3768"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Adhesive bonding of beech wood modified with a phenol formaldehyde compound"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.subtype","letter_note"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","165"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Wood Science and Technology"],["dc.bibliographiccitation.lastpage","178"],["dc.bibliographiccitation.volume","50"],["dc.contributor.author","Hosseinpourpia, Reza"],["dc.contributor.author","Adamopoulos, Stergios"],["dc.contributor.author","Mai, Carsten"],["dc.date.accessioned","2018-11-07T10:21:31Z"],["dc.date.available","2018-11-07T10:21:31Z"],["dc.date.issued","2016"],["dc.description.abstract","Micro-veneers of wood and holocellulose (HC) were modified with the thermosetting resins phenol formaldehyde and melamine formaldehyde. The dynamic water vapour sorption of the modified and untreated veneers was studied in a dynamic vapour sorption apparatus to assess the effects of resin modification. The adsorption of wood and HC as well as the desorption of wood was little affected by the modification in the low relative humidity (RH) range but decreased in the RH range above 60-70 %. The desorption isotherm of HC, however, was increased in the RH range of 15-80 % due to modification. Resin modification gradually decreased the EMC ratio of wood and HC and also influenced the moisture increment, equilibrium time and sorption rate in RH range above 50-60 % RH for wood and above 70-80 % RH for HC. HC exhibited a clearly lower hysteresis than wood. Modification of wood slightly reduced hysteresis compared to untreated wood, but modification of HC clearly increased hysteresis about to the same extent as that of wood. This indicates that the stiffening effect of lignin and thermosetting resins reduces the flexibility of the HC matrix, which results in increased hysteresis."],["dc.description.sponsorship","German Academic Exchange Service (DAAD)"],["dc.identifier.doi","10.1007/s00226-015-0765-1"],["dc.identifier.isi","000367922200011"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/42107"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","1432-5225"],["dc.relation.issn","0043-7719"],["dc.title","Dynamic vapour sorption of wood and holocellulose modified with thermosetting resins"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","749"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","Wood Science and Technology"],["dc.bibliographiccitation.lastpage","767"],["dc.bibliographiccitation.volume","46"],["dc.contributor.author","Xiao, Zefang"],["dc.contributor.author","Xie, Yanjun"],["dc.contributor.author","Adamopoulos, Stergios"],["dc.contributor.author","Mai, Carsten"],["dc.date.accessioned","2018-11-07T09:08:56Z"],["dc.date.available","2018-11-07T09:08:56Z"],["dc.date.issued","2012"],["dc.description.abstract","Scots pine sapwood was treated with glutaraldehyde (GA) in aqueous solution using magnesium chloride as a catalyst in order to evaluate the durability towards weathering. Infrared spectroscopy suggested that GA treatment increased the photo-stability of lignin during artificial weathering of micro-veneers in a QUV over 168 h; photo-protection increased with increasing GA concentration. In comparison with the unmodified controls, GA-modified pine micro-veneer strips exhibited a lower tensile strength loss measured in a zero-span mode in the course of weathering. During 18 months of outdoor exposure, GA-modified pine wood boards exhibited a lower moisture content and water uptake than the unmodified ones. GA treatment also clearly restricted the penetration of blue stain fungi into deeper layers of wood. On the macroscopic scale, the surface of the GA-modified boards was significantly smoother due to less erosion, cracking and minor peeling of tracheids. Scanning electron microscopy further revealed that individual tracheids were detached from the cell compound and then washed away from the unmodified wood surface, whereas tracheids on surfaces of GA-modified wood remained in the tissue compound but displayed many axial and transversal cracks."],["dc.identifier.doi","10.1007/s00226-011-0441-z"],["dc.identifier.isi","000305135000013"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/8084"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/26144"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","0043-7719"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Effects of chemical modification with glutaraldehyde on the weathering performance of Scots pine sapwood"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","959"],["dc.bibliographiccitation.issue","8"],["dc.bibliographiccitation.journal","Holzforschung"],["dc.bibliographiccitation.lastpage","966"],["dc.bibliographiccitation.volume","69"],["dc.contributor.author","Adamopoulos, Stergios"],["dc.contributor.author","Hosseinpourpia, Reza"],["dc.contributor.author","Mai, Carsten"],["dc.date.accessioned","2018-11-07T09:51:08Z"],["dc.date.available","2018-11-07T09:51:08Z"],["dc.date.issued","2015"],["dc.description.abstract","This study was conducted to explain the tensile strength loss of wood due to the modification with 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU) and glutaraldehyde (GA). Modified and control wood blocks were macerated to deliberate fibres, and handsheets were produced thereof. The nitrogen content of the fibres indicated that maceration removed the major proportions of DMDHEU. The stability of GA in wood during maceration was not assessed. Tensile strength determined at zero span (z-strength) and finite span (f-strength) was equal for the handsheets from DMDHEU-modified fibres and the control handsheets. The microscopic appearance of the tested finite-span paper strips from DMDHEU-modified fibres mainly indicated interfibre failure and did not differ from the fibre fracture mode of the control handsheets. In contrast, the z-strength of the handsheets from GA-modified fibres was lower than that of controls and decreased with increasing content of GA in the initial modified wood. The f-strength behaviour of the handsheets from GA-modified fibres was the opposite: it was higher than that of controls and increased with increasing GA content. The microscopic appearance of the rapture zones of the finite-span testing mainly indicated intrafibre failure for the GA-modified fibres. It was concluded that cross-linking is likely to be the major reason for tensile strength loss of GA- and DMDHEU-modified wood. In terms of DMDHEU-modified wood, the incrustation of the cell wall by the resin and the reduction in pliability could play an additional role."],["dc.identifier.doi","10.1515/hf-2014-0216"],["dc.identifier.isi","000361831200005"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/35851"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Walter De Gruyter Gmbh"],["dc.relation.issn","1437-434X"],["dc.relation.issn","0018-3830"],["dc.title","Tensile strength of handsheets prepared with macerated fibres from solid wood modified with cross-linking agents"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]