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1.	Abbadessa, Anna, et al. (författare) Characterization of Two Novel Bio-based Materials from Pulping Process Side Streams : Ecohelix and CleanFlow Black Lignin 2018 Ingår i: BioResources. - : NORTH CAROLINA STATE UNIV DEPT WOOD & PAPER SCI. - 1930-2126. ; 13:4, s. 7606-7627 Tidskriftsartikel (refereegranskat)abstract The characteristics of two novel types of technical lignin, namely Ecohelix (EH) and CleanFlow black lignin (CFBL), isolated from two different pulping process side streams, were analyzed. EH and CFBL were analyzed in terms of general composition, chemical functionalities, molar mass distribution, and thermal stability. For comparison, two relevant types of commercially available lignosulfonate and kraft lignin were used. The results showed that EH contains a large amount of sulfonated lignin, together with carbohydrates and ash. As such, it can be considered a lignin-carbohydrate hybrid molecule. CFBL was found to contain 91.5% Klason lignin and the lowest amount of carbohydrates (0.3%). EH showed the highest content of aliphatic OH groups (5.44 mmol/g) and CFBL a high content of phenols (4.73 mmol/g). EH had a molecular weight of 31.4 kDa and a sufficient thermal stability. CFBL had the lowest molecular weight (M-w = 2.0 kDa) and thermal stability of all kraft lignins analyzed in this study. These properties highlighted that EH is a suitable building block for material development and that CFBL is a promising material for the production of biofuel and biochemicals.
2.	Adamopoulos, Stergios, et al. (författare) Manufacturing and properties of gypsum-based products with recovered wood and rubber materials 2015 Ingår i: BioResources. - : BioResources. - 1930-2126. ; 10:3, s. 5573-5585 Tidskriftsartikel (refereegranskat)abstract The experimental production of gypsum-based products (cylindrical samples, solid bricks) using different fractions of wood chips and rubber particles was studied. Recovered rubber and wood materials were mixed with gypsum and water in various proportions to fabricate gypsum-wood and gypsum-rubber cylindrical samples and standard solid bricks with six holes using appropriate molds. It was shown that to manufacture gypsum-wood and gypsum-rubber products with good mechanical strength, coarse fractions of wood and rubber should be used, but the proportion of wood or rubber should not exceed 25%. No thermal conductivity differences were found between the wood-and rubber-type of gypsum products, and particle size and material proportion had no effect. Samples with fine wood and rubber particles present at a lower proportion (25%) exhibited similar sound absorption behavior. The solid bricks had slightly higher strength when loaded at the large surface of their lateral upper side than when loaded at the small surface. The bricks provided better thermal insulation than both the extruded and pressed house bricks but lower than that of insulating bricks. The emission of volatile organic compounds out of the bricks was at an acceptable level according to regulations for construction products.
3.	Ah Shenga, Pedro, et al. (författare) 3D Phase-shift Laser Scanning of Log Shape 2014 Ingår i: BioResources. - : BioResources. - 1930-2126. ; 9:4, s. 7593-7605 Tidskriftsartikel (refereegranskat)abstract In this paper, a portable scanner to determine the 3D shape of logs was evaluated and compared with the measurement result of a computer tomography scanner. Focus was on the accuracy of the shape geometry representation. The objective is to find a feasible method to use for future data collection in Mozambique in order to build up a database of logs of tropical species for sawing simulations. The method chosen here was a 3D phase-shift laser scanner. Two logs, a birch log with bark and a Scots pine log without bark, were scanned, resulting in 450 cross sectional “images” of the pine log and 300 of the birch log. The areas of each point cloud cross section were calculated and compared to that of the corresponding computer tomography cross section. The average area difference between the two methods was 2.23% and 3.73%, with standard deviations of 1.54 and 0.91, for the Scots pine and birch logs, respectively. The differences in results between the two logs are discussed and had mainly to do with presence of bark and mantle surface evenness. Results show that the shape measurements derived from these methods were well correlated, which indicates the applicability of a 3D phase-shift laser scanning technology for gathering log data.
4.	Ah Shenga, Pedro, et al. (författare) Simulation of Tropical Hardwood Processing – Sawing Methods, Log Positioning, and Outer Shape 2015 Ingår i: BioResources. - : BioResources. - 1930-2126. ; 10:4, s. 7640-7652 Tidskriftsartikel (refereegranskat)abstract To increase understanding of breakdown strategies for Mozambican timber, simulations were carried out using different sawing patterns that can be alternatives to the low degree of refinement performed for export today. For the simulations, 3D models of 10 Jambirre and 5 Umbila logs were used. The log shape was described as a point cloud and was acquired by 3D-laser scanning of real logs. Three sawing patterns (cant-sawing, through-and-through sawing, and square-sawing) were studied in combination with the log positioning variables skew and rotation. The results showed that both positioning and choice of sawing pattern had a great influence on the volume yield. The results also showed that the log grade had an impact on the sawing pattern that should be used for a high volume yield. The volume yield could be increased by 3 percentage points by choosing alternative sawing patterns for fairly straight logs and by 6 percentage points for crooked logs, compared to the worst choice of sawing pattern.
5.	Ah Shenga, Pedro, et al. (författare) The Effect of Log Position Accuracy on the Volume Yield in Sawmilling of Tropical Hardwood 2016 Ingår i: BioResources. - : BioResources. - 1930-2126. ; 11:4, s. 9560-9571 Tidskriftsartikel (refereegranskat)abstract This study investigated the effect of the positioning of the log before sawing on the volume yield of sawn timber from tropical hardwood species. Three positioning parameters were studied, the offset, skew, and rotation, combined with two sawing patterns of cant-sawing and through-and-through sawing. A database consisting of two tropical hardwood species with very different outer shapes, jambirre (Millettia stuhllmannii Taub.) and umbila (Pterocarpus angolensis DC.), was used to simulate the sawing process. The result of the simulation revealed that, according to the combined effect of offset, skew, and rotation positioning, the positioning of the log before sawing is extremely important to achieve a high volume yield of sawn timber. The positioning parameter that has the highest effect on the volume yield is the rotation, and the variation in the volume yield associated with a deviation in the positioning can reduce the volume yield of sawn timber by between 7.7% and 12.5%.
6.	Akinbomi, Julius, et al. (författare) Development and dissemination strategies for accelerating biogas production in Nigeria 2014 Ingår i: BioResources. - : NC State University. - 1930-2126. ; 9:3, s. 5707-5737 Tidskriftsartikel (refereegranskat)abstract Following the worsening energy crisis of unreliable electricity and unaffordable petroleum products coupled with the increase number of poverty-stricken people in Nigeria, the populace is desperately in need of cheap alternative energy supplies that will replace or complement the existing energy sources. Previous efforts by the government in tackling the challenge by citizenship sensitization of the need for introduction of biofuel into the country’s energy mix have not yielded the expected results because of a lack of sustained government effort. In light of the shortcomings, this study assesses the current potential of available biomass feedstock for biogas production in Nigeria, and further proposes appropriate biogas plants, depending on feedstock type and quantity, for the six geopolitical zones in Nigeria. Besides, the study proposes government-driven biogas development systems that could be effectively used to harness, using biogas technology, the estimated 270 TWh of potential electrical energy from 181 million tonnes of available biomass, in the advancement of electricity generation and consequent improvement of welfare in Nigeria.
7.	Almlöf, Heléne, 1968-, et al. (författare) Carboxymethyl cellulose produced at different mercerization conditions and characterized by NIR FT Raman spectroscopy and chemometric methods 2013 Ingår i: BioResources. - 1930-2126. ; 8:2, s. 1918-1932 Tidskriftsartikel (refereegranskat)
8.	Amiandamhen, Stephen, 1983-, et al. (författare) Bioenergy production and utilization in different sectors in Sweden: A state of the art review 2020 Ingår i: BioResources. - : University of North Carolina Press. - 1930-2126. ; 15:4, s. 9834-9857 Forskningsöversikt (refereegranskat)abstract In the continual desire to reduce the environmental footprints of human activities, research efforts to provide cleaner energy is increasingly becoming vital. The effect of climate change on present and future existence, sustainable processes, and utilizations of renewable resources have been active topics within international discourse. In order to reduce the greenhouse gases emissions from traditional materials and processes, there has been a shift to more environmental friendly alternatives. The conversion of biomass to bioenergy, including biofuels has been considered to contribute to the future of climate change mitigation, although there are concerns about carbon balance from forest utilization. Bioenergy accounts for more than one-third of all energy used in Sweden and biomass has provided about 60% of the fuel for district heating. Apart from heat and electricity supply, the transport sector, with about 30% of global energy use, has a significant role in a sustainable bioenergy system. This review presents the state of the art in the Swedish bioenergy sector based on literature and Swedish Energy Agency’s current statistics. The review also discusses the overall bioenergy production and utilization in different sectors in Sweden. The current potential, challenges, and environmental considerations of bioenergy production are also discussed.
9.	Ander, Paul, et al. (författare) ASPECTS ON BLEACHING AND TEMPO-MEDIATED OXIDATION OF WHEAT STRAW PULP FRACTIONS 2012 Ingår i: Bioresources. - 1930-2126. ; 7, s. 3051-3063 Tidskriftsartikel (refereegranskat)abstract This study outlines research concerning wheat straw fines, including their impact on pulp bleachability, their modification by chemical means, and their use as a dry strength enhancer in a paper application. Results show that primary fines constituting about 23% of the whole wheat straw pulp had a large negative impact on pulp bleachability. The differences in response to bleaching were due to the different properties of the fines, i.e. higher kappa number, higher metal ion content, lower brightness, and lower viscosity compared to that of fibers. It was also shown that the fines fraction is more difficult to oxidize and does not reach as high fiber charge levels as that of the other fractions. However, at a dosage of >= 3 mmol hypochlorite/g it was possible to prepare nanofibers from wheat straw fines that showed a good strength-enhancing effect in a paper product. The fact that removal of fines from wheat straw pulps by fractionation improves bleachability and also drainage properties at the same time, while simultaneously the fines can be modified and used as a strength enhancer, is very interesting when evaluating the potential of this type of annual plant as a source for production of different paper products.
10.	Arino Marine, Ruth, 1980, et al. (författare) Thermal and viscoelastic properties of cellulosic gels with different ionic liquids and coagulation agents 2013 Ingår i: BioResources. - 1930-2126 .- 1930-2126. ; 8:2, s. 2209-2221 Tidskriftsartikel (refereegranskat)abstract Thermal and viscoelastic properties of three-component gels consisting of microcrystalline cellulose, ionic liquid, and coagulation agent were studied. The amount and type of components was varied to obtain different gel properties. The absorption of coagulation agent (13 to 35 %wt of water or ethanol) was found to depend on the types of ionic liquid and cellulose. Surface hydrophobization of cellulose prior to preparation of the gel remarkably resulted in the gels containing the most coagulation agent (35%wt). Rheological studies indicated a linear viscoelastic behavior in storage modulus but not in loss modulus, which is a behavior that, according to our knowledge, has not been seen before for gels. Increasing the cellulose concentration from 1:20 to 1:10 increased the stiffness of the gels. The highest critical stress value (1050 Pa) was obtained for a gel containing 1-butyl-3-methylimidazolium chloride and water. Finally, it was confirmed by dynamic-mechanical experiments that the gels had a cross-linked structure.
11.	Arshadi, Mehrdad (författare) Food Waste and Byproduct Valorization through Bio-processing: Opportunities and Challenges 2014 Ingår i: Bioresources. - : BioResources. - 1930-2126. ; 9, s. 5774-5777 Annan publikation (refereegranskat)abstract The bioeconomy era will rely on efficient fractionation of renewable resources via integrated biorefineries. The food supply chain waste, despite its inherent variability, could evolve into an important industrial feedstock on account of its availability, versatility, and sustainability, for the production of bio-based products. Waste streams generated from all stages of the life cycle of food products could be refined into different fractions, which will be either purified to high-value molecules or converted via green chemical and/or biotechnological routes for the production of bio-based products. A working group of the EUBis COST Action TD1203 is taking steps to gather a critical mass of knowledge and expertise to create innovation and technological breakthroughs.
12.	Asadollahzadeh, Mohammadtaghi, et al. (författare) Production of Fungal Biomass Protein by Filamentous Fungi Cultivation on Liquid Waste Streams from Pulping Process 2018 Ingår i: BioResources. - 1930-2126. ; 13:3, s. 5013-5031 Tidskriftsartikel (refereegranskat)abstract The aim of this study was to convert the spent liquors obtained from acidic sulfite and neutral sulfite semi-chemical (NSSC) pulping processes into protein-rich fungal biomass. Three filamentous fungi, Aspergillus oryzae, Mucor indicus, and Rhizopus oryzae, were cultivated on the diluted spent liquors in an airlift bioreactor with airflow of 0.85 vvm at 35 degrees C and pH 5.5. Maximum values of 10.17 g, 6.14 g, and 5.47 g of biomass per liter of spent liquor were achieved in the cultivation of A. oryzae, M. indicus, and R. oryzae on the spent sulfite liquor (SSL) diluted to 60%, respectively, while A. oryzae cultivation on the spent NSSC liquor (SNL) diluted to 50% resulted in the production of 3.27 g biomass per liter SNL. The fungal biomasses contained 407 g to 477 g of protein, 31 g to 114 g of fat, 56 g to 89 g of ash, and 297 g to 384 g of alkali-insoluble material (AIM) per kg of dry biomass. The amino acids, fatty acids, and mineral elements composition of the fungal biomasses corresponded to the composition of commercial protein sources especially soybean meal. Among the fungi examined, A. oryzae showed better performance to produce protein-rich fungal biomass during cultivation in the spent liquors.
13.	Asadollahzadeh, M., et al. (författare) Production of fungal biomass protein by filamentous fungi cultivation on liquid waste streams from pulping process 2019 Ingår i: BioResources. - : North Carolina State University. - 1930-2126. ; 13:3, s. 5013-5031 Tidskriftsartikel (refereegranskat)abstract The aim of this study was to convert the spent liquors obtained from acidic sulfite and neutral sulfite semi-chemical (NSSC) pulping processes into protein-rich fungal biomass. Three filamentous fungi, Aspergillus oryzae, Mucor indicus, and Rhizopus oryzae, were cultivated on the diluted spent liquors in an airlift bioreactor with airflow of 0.85 vvm at 35°C and pH 5.5. Maximum values of 10.17 g, 6.14 g, and 5.47 g of biomass per liter of spent liquor were achieved in the cultivation of A. oryzae, M. indicus, and R. oryzae on the spent sulfite liquor (SSL) diluted to 60%, respectively, while A. oryzae cultivation on the spent NSSC liquor (SNL) diluted to 50% resulted in the production of 3.27 g biomass per liter SNL. The fungal biomasses contained 407 g to 477 g of protein, 31 g to 114 g of fat, 56 g to 89 g of ash, and 297 g to 384 g of alkali-insoluble material (AIM) per kg of dry biomass. The amino acids, fatty acids, and mineral elements composition of the fungal biomasses corresponded to the composition of commercial protein sources especially soybean meal. Among the fungi examined, A. oryzae showed better performance to produce protein-rich fungal biomass during cultivation in the spent liquors.
14.	Aski, Abolfazl Lotfi, et al. (författare) Effect of Steam Explosion on the Structural Modification of Rice Straw for Enhanced Biodegradation and Biogas Production 2019 Ingår i: BioResources. - 1930-2126. ; 14:1, s. 464-485 Tidskriftsartikel (refereegranskat)abstract The goal of this study was to develop an operational steam explosion pretreatment for effective modification of rice straw chemical structure in order to improve its biodegradability and methane yield. The parameters of pressure (5 bar to 15 bar), moisture (0% to 70%), and time (1 min to 15 min) were studied in steam explosion pretreatment. The steam explosion efficiency was investigated according to the changes in crystallinity structure and chemical composition on rice straw, as well as the methane yield from straw. Steam explosion changed the structure linkages between the lignin and carbohydrate, which was indicated by a reduction in the peak intensities in the bonds from 1648 cm(-1) to 1516 cm(-1). After pretreatment, the crystallinity index of the rice straw in the 10 bar-10 min cycle with no moisture and 15 bar-10 min cycle with 70% moisture increased from 22.9% to 28.3% and 28.6%, respectively. Steam explosion efficiently decreased the lignin. The highest reduction in the amount of lignin was observed with the 10 bar-10 min cycle, which reached from 18.6% to 13.0%. The methane yield increased with the cycles 10 bar-10 min and 15 bar-15 min with 35% moisture, and 15 bar-10 min with 70% moisture by 113%, 104%, and 147% compared to that of the untreated straw, respectively. Moreover, the highest biodegradation percent of the rice straw was obtained in these cycles.
15.	Aslanzadeh, Solmaz, et al. (författare) Pretreatment of straw fraction of manure for improved biogas production 2011 Ingår i: BioResources. - 1930-2126. ; 6:4, s. 5193-5205 Tidskriftsartikel (refereegranskat)abstract Pretreatment of straw separated from cattle and horse manure using N-methylmorpholine oxide (NMMO) was investigated. The pretreatment conditions were for 5 h and 15 h at 120 °C, and the effects were evaluated by batch digestion assays. Untreated cattle and horse manure, both mixed with straw, resulted in 0.250 and 0.279 Nm3 CH4/kgVS (volatile solids), respectively. Pretreatment with NMMO improved both the methane yield and the degradation rate of these substrates, and the effects were further amplified with more pretreatment time. Pretreatment for 15 h resulted in an increase of methane yield by 53% and 51% for cattle and horse manure, respectively. The specific rate constant, k0, was increased from 0.041 to 0.072 (d-1) for the cattle and from 0.071 to 0.086 (d-1) for the horse manure. Analysis of the pretreated straw shows that the structural lignin content decreased by approximately 10% for both samples and the carbohydrate content increased by 13% for the straw separated from the cattle and by 9% for that separated from the horse manure. The crystallinity of straw samples analyzed by FTIR show a decrease with increased time of NMMO pretreatment.
16.	Aslanzadeh, Solmaz, et al. (författare) Pretreatment of straw fraction of manure for improved biogas production 2011 Ingår i: BioResources. - 1930-2126. ; 6:4, s. 5193-5205 Tidskriftsartikel (refereegranskat)
17.	Axelsson, Ann (författare) How Planer Settings Affect Timber Properties 2014 Ingår i: BioResources. - : BioResources. - 1930-2126. ; 9:4, s. 6432-6439 Tidskriftsartikel (refereegranskat)abstract There are different reasons for planing timber. One is to adjust the cross-sectional dimensions of thickness and width. Another is to adjust the timber's outer shape, usually in order to reduce warp resulting from drying and having the forms of cup, twist, bow, and crook. The end-result depends on the properties of the timber before planing and on the planer design and settings. In the present work it was found that increasing or decreasing the forces exerted on the timber by a four-sided planer does not affect the cutting depth or the twist reduction. The pressure settings do not affect the rectangularity or the amount of unplaned areas on the surfaces either. The possibility to impact the result with this type of planer, apart from the cutting depth and planed dimensions, is slim to none.
18.	Azhar, Shoaib, et al. (författare) Extraction of polymers from enzyme-treated softwood 2011 Ingår i: BioResources. - 1930-2126. ; 6:4, s. 4606-4614 Tidskriftsartikel (refereegranskat)abstract In a biorefinery context it is an advantage to fractionate and extract different wood components in a relatively pure form. However, one major obstacle for efficient extraction of wood polymers (lignin, polysaccharides etc.) is the covalent lignin-polysaccharide networks present in lignified cell walls. Enzymatic catalysis might be a useful tool for a controlled degradation of these networks, thereby enhancing the extraction of high molecular weight polymers. In this work, a methanol-alkali mixture was used to extract two different wood samples treated with endoxylanase and gammanase, respectively. Wood chips were pretreated with alkali prior to enzymatic treatment to enhance the cell-wall accessibility to enzymes. Extractions were also carried out on non-enzyme-treated samples to evaluate the enzymatic effects. Results showed that the enzymatic treatment increased the extraction yield, with gammanase as the more efficient of the two enzymes. Furthermore, polymers extracted from xylanase-treated wood had a higher degree of polymerization than the reference.
19.	Balducci, Francesco, et al. (författare) A formaldehyde-free adhesive for particleboards based on soy flour, magnesium oxide, and a plant-derived enzymatic hydrolysate 2020 Ingår i: BioResources. - : North Carolina State University. - 1930-2126. ; 15:2, s. 3087-3102 Tidskriftsartikel (refereegranskat)abstract An adhesive for particleboards based on natural materials was prepared. Soy flour (38.9 wt%), magnesium oxide (MgO) (2.8 wt%), and a hydrolysate from an agricultural crop (13.9 wt%) were mixed with water and ground in a ball mill at 44% solids. The solubility and interaction of the soy flour proteins and the proteins contained in the plant hydrolysate were triggered by the strong basic environment created by MgO in the presence of water. The natural adhesive appeared to be thermally stable at temperatures from 130 °C to 240 °C, with unchanged mass and no major signals in the thermal analysis curves. These results, together with a viscosity of 510 Pa·s at 25 °C, suggested a good operability of the adhesive. Three-layered particleboards were manufactured with weight combinations of natural adhesive and polyamidoamine-epichlorohydrin (PAE) of 0%:100%, 33%:67%, 50%:50%, 67%:33%, and 100%:0%. The natural adhesive showed inferior internal bond strength and poor water resistance compared with urea-formaldehyde-bonded boards. Addition of the PAE significantly improved the internal bond and swelling, and for all the combinations these properties were comparable or, in most cases, better than in the urea-formaldehyde controls. All boards were formaldehyde-free, while the natural adhesive itself released no dangerous volatile substances
20.	Bátori, Veronika, 1980-, et al. (författare) Synthesis and characterization of maleic anhydride-grafted orange waste for potential use in biocomposites 2018 Ingår i: BioResources. - : BioResources. - 1930-2126. ; 13:3, s. 4986-4997 Tidskriftsartikel (refereegranskat)abstract The purpose of the study was to develop a less hydrophilic, and therefore more useful, material from orange waste produced in large quantities by the food industry. A new derivative of industrial orange waste was synthesized via esterification with maleic anhydride. The reaction was confirmed via Fourier transform infrared spectroscopy (FTIR), and the degree of substitution of the hydroxyl groups was 0.39 ± 0.01, as determined by a back-titration method. A major change in physical structure was confirmed by scanning electron microscopy (SEM). The flake-like structure of orange waste changed to a sponge-like structure after the reaction, which involved an increased volume and a reduced density by approximately 40%. The sponge-like structure was represented as an agglomeration of particles with a low specific surface area of 2.18 m2/g and a mean pore diameter of 10.7 nm. Interestingly, the grafted orange waste seemed to become more hydrophobic, which was confirmed by a contact angle test; however, the material absorbed more water vapor. Thermogravimetric analysis (TGA) confirmed a thermally more uniform, though, less heat-resistant material. This work suggests a possible way of utilizing orange waste via synthesizing a renewable material with possible applications as a filler in biocomposites.
21.	Berg, Sven, et al. (författare) In-plane Shear Modulus of Cross-laminated Timber by Diagonal Compression Test 2019 Ingår i: BioResources. - : NC State University. - 1930-2126. ; 14:3, s. 5559-5572 Tidskriftsartikel (refereegranskat)abstract Cross-laminated timber (CLT) is an engineered wood material that is used in the construction industry, e.g., for floors, walls, and beams. In cases where CLT-elements are used as shear walls, the in-plane-stiffness is an important property. For non-edge glued CLT, in-plane shear stiffness is lower than for edge-glued CLT. To evaluate the non-edge glued CLT panel’s in-plane shear modulus, the diagonal compression test and finite element (FE) simulation was used. FE-models with both isotropic and orthotropic material models were used to calculate the shear stiffness. The FE models using pure shear loads were used as a reference to determine the correct value of the shear modulus. To verify the FE simulations, diagonal compression tests were conducted on 30 CLT samples. A calibration formula was derived using the least square method for calculation of shear modulus. The formula gave accurate results. The results showed that FE simulations can reproduce the same shear stiffness as tests of non-edge glued 3-layer and 5-layer CLT panels.
22.	Bi, Ran, 1985-, et al. (författare) A Method for Studying Effects on Lignin-Polysaccharide Networks during Biological Degradation and Technical Processes of Wood 2016 Ingår i: BioResources. - : NORTH CAROLINA STATE UNIV. - 1930-2126. ; 11:1, s. 1307-1318 Tidskriftsartikel (refereegranskat)abstract Woody tissues consist primarily of a mixture of cellulose, hemicelluloses, and lignin. Covalent bonds between lignin and polysaccharides likely play a central role in determining the mechanical and physical properties of wood. Intact and defined lignin-polysaccharide networks have not been isolated in large quantities because of the recalcitrance of lignin, which demands harsh chemical treatments that alter its structure. This report presents a method for preparing large quantities of lignin-polysaccharide networks similar to those naturally present in wood based on the enzymatic oxidation of hemicellulose from Norway spruce. Fungal enzymes produced from various carbon sources were used to depolymerize these networks. The method was used for simulating "enzyme mining" - a concept in biorefineries, giving a possible explanation for its mechanisms.
23.	Biological pretreatment of lignocelluloses with white-rot fungi and its applications : A review 2011 Ingår i: BioResources. - 1930-2126. ; 6:4, s. 5224-5259 Tidskriftsartikel (refereegranskat)
24.	Björngrim, Niclas, et al. (författare) Factory Mounted and Retrofit Passive Resistance Sensors Adapted to Monitor Moisture Content in Timber Bridges 2017 Ingår i: BioResources. - : North Carolina State University. - 1930-2126. ; 12:4, s. 7218-7227 Tidskriftsartikel (refereegranskat)abstract The biggest threats to the longevity of a timber bridge are rot and decay. Wood protection by design, inspections, and monitoring of the bridge for elevated moisture content will ensure that the full service life of the structure can be achieved. Today's sensors for moisture content measurements are limited in their functionality and range. This paper presents a sensor that can be both factory installed and retrofitted, which can measure the moisture content through the cross-section of the member in a timber bridge. The sensor has been mounted on Sundbron bridge during manufacturing and retrofitted on Gislaved bridge. The ensuing measurements helped to adjust a design flaw on Gislaved bridge. Monitoring of Sundbron showed that the bridge deck dried up after the bridge had been exposed to sleet and snow during the on-site assembly of the stress laminated bridge deck
25.	Björngrim, Niclas, et al. (författare) Moisture Content Monitoring of a Timber footbridge 2016 Ingår i: BioResources. - : BioResources. - 1930-2126. ; 11:2, s. 3904-3913 Tidskriftsartikel (refereegranskat)abstract Construction of modern timber bridges has greatly increased during the last 20 years in Sweden. Wood as a construction material has several advantageous properties, e.g., it is renewable, sustainable, and aesthetically pleasing, but it is also susceptible to deterioration. To protect wood from deterioration and ensure the service life, the wood is either treated or somehow covered. This work evaluates a technology to monitor the moisture content in wood constructions. Monitoring the moisture content is important both to verify the constructive protection and for finding areas with elevated levels of moisture which might lead to a microbiological attack of the wood. In this work, a timber bridge was studied. The structure was equipped with six wireless sensors that measured the moisture content of the wood and the relative humidity every hour. Data for 744 days of the bridge are presented in this paper. Results show that the technology used to monitor the bridge generally works; however, there were issues due to communication problems and malfunction of sensors. This technology is promising for monitoring the state of wood constructions, but a more reliable sensor technology is warranted continuous remote monitoring of wood bridges over long periods of time.
26.	Björngrim, Niclas, et al. (författare) Multivariate Screening of the Weather Effect on Timber Bridge Movements 2016 Ingår i: BioResources. - : BioResources. - 1930-2126. ; 11:4, s. 8890-8899 Tidskriftsartikel (refereegranskat)abstract Monitoring displacements and weather impact of complex structures such as a large cable stayed footbridge generates large amount of data. In order to extract, visualize and classify health-monitoring data to get a better comprehension multivariate statistical analysis is a powerful tool. This paper is a screening to evaluate if principal component analysis is useful on health monitoring data. Principal component analysis (PCA) and projections to latent structures by means of partial least squares (PLS) modeling were used to achieve a better understanding of the complex interaction between bridge dynamics and weather effects. The results show that principal component analysis (PCA) give good overview of the collected data, and PLS modeling show that winds from east and west best explain bridge movements.
27.	Björngrim, Niclas, et al. (författare) Resistance measurements to find high moisture content inclusions adapted for large timber bridge cross-sections 2017 Ingår i: BioResources. - : North Carolina State University. - 1930-2126. ; 12:2, s. 3570-3582 Tidskriftsartikel (refereegranskat)abstract One challenge of monitoring and inspecting timber bridges is the difficulty of measuring the moisture content anywhere other than close to the surface. Damage or design mistakes leading to water penetration might not be detected in time, leading to costly repairs. By placing electrodes between the glulam beams, the moisture content through the bridge deck can be measured. Due to the logarithmic decrease of the resistance in wood as a function of electrode length, the model must be calibrated for measurement depth. Two models were created: one for electrode lengths of 50 mm and one for electrode lengths up to 1355 mm. The model for short electrodes differed by no more than 1 percentage points compared with the oven dry specimens. The model for long electrodes differed up to 2 percentage points for lengths up to 905 mm, and over that it could differ up to 4 percentage points.
28.	Blomqvist, Lars, 1962-, et al. (författare) Distortion in laminated veneer products exposed to relative-humidity variations : Experimental studies and finite-element modelling 2019 Ingår i: BioResources. - Raleigh, NC : North Carolina State Univ Dept Wood & Paper Sci. - 1930-2126. ; 14:2, s. 3768-3779 Tidskriftsartikel (refereegranskat)abstract A shortcoming of the laminated bending process is that the product may become distorted after moulding. This study focused on the influence of fibre orientation deviation for individual veneers on the distortion of a moulded shell. The distortion of 90 cross-laminated shells of the same geometrical shape, consisting of seven peeled birch veneers, were studied under relative humidity variation. All the veneers were straight-grained in the longitudinal-tangential plane, but to simulate a deviation in fibre orientation, some of the individual veneers were oriented at an angle of 7° relative to the main orientation of the other veneers in the laminate. A finite element model (FEM) was applied to study the possibility of predicting the results of a practical experiment. The study confirms the well-known fact that deviation in fibre orientation influences shape stability. The results also show how the placement of the abnormal veneer influences the degree of distortion. From this basic knowledge, some improvements in the industrial production were suggested. However, the FE model significantly underestimated the results, according to the empirical experiment, and it did not show full coherence. The survey shows the complexity of modelling the behaviour of laminated veneer products under changing climate conditions and that there is a great need to improve the material and process data to achieve accurate simulations. Examples of such parameters that may lead to distortion are density, annual ring orientation in the cross section of the veneer, the orientation of the loose and tight sides of the veneer, and parameters related to the design of the moulding tool.
29.	Bobadilha, Gabrielly S., et al. (författare) Effect of exterior wood coatings on the durability of cross-laminated timber against mold and decay fungi 2020 Ingår i: BioResources. - USA : North Carolina State University. - 1930-2126. ; 15:4, s. 8420-8433 Tidskriftsartikel (refereegranskat)abstract Cross-laminated timber (CLT) is increasingly used in building construction worldwide. Durability of CLT against fungal attack has yet to be fully explored. Water intrusion in mass timber can yield dimensional changes and microbial growth. This study evaluated the performance of CLT coated with various water- and solvent-based stains commercially available in the United States. Twelve coatings were tested for moisture excluding effectiveness, water repellency effectiveness, volumetric swelling, and anti-swelling efficiency. Only five coatings repelled water, limiting dimensional changes. A modified version of AWPA E10-16 (2016) was performed to evaluate decay of the coated CLT samples. Weight losses were recorded after 18 weeks' exposure to the brown-rot decay fungus Gloeophyllum trabeum. In accelerated mold testing, coated CLT samples were grown in chambers containing spores of Aspergillus sp., Rhizopus sp., and Penicillium sp. for 29 d and assessed visually for mold growth. In both tests, coating C (transparent, water-based, alkyd/acrylic resin) performed the best among the tested coatings. Mold growth was completely prevented, and weight loss caused by G. trabeum was approximately 1.33%. Although coating C prevented decay for 18 weeks, coatings are not intended to protect against decay fungi. However, they may offer short-term protection during transport, storage, and construction.
30.	Boudreau, Jonna, et al. (författare) Influence of Various Pulp Properties on the Adhesion Between Tissue Paper and Yankee Cylinder Surface 2014 Ingår i: BioResources. - North Carolina : North Carolina State University. - 1930-2126. ; 9:2, s. 2107-2114 Forskningsöversikt (refereegranskat)abstract The strength of the adhesion between the paper and the drying Yankee cylinder is of great importance with respect to the final properties of a tissue paper product. Therefore, the effects of a few potentially important pulp properties have been evaluated in laboratory experiments. Four highly different kraft pulps were used, and the adhesion strength was measured by means of the force required when scraping off a paper from a metal surface with a specifically designed knife mounted on a moving cart. The adhesion strength was observed to increase with increasing grammage and increasing degree of beating of the pulp. It was also found that pulpscontainingmore fines, or with higher hemicellulose content, gave rise to higher adhesion strength.
31.	Brännström, Mattias, et al. (författare) Predicting the strength of sawn wood by tracheid laser scattering 2008 Ingår i: BioResources. - 1930-2126. ; 3:2, s. 437-451 Tidskriftsartikel (refereegranskat)abstract An industrial laser light scattering scanner, designed to detect the spiral grain angle of logs by the light scattering along the grain, was used on two large samples of Norway spruce (Picea abies (var. Karst)) in various sawn dimensions (approximately 750 pieces). Additional measurements were made by other techniques, such as X-ray scanning, resonance frequency measurement, and various manual measurements. The strength properties of the boards were measured by destructive testing in four-point bending according to European standard. Multivariate methods (PLS) were used to model the relationship between the bending strength of the board (MOR) and the measurements. Based only on the output from the simple tracheid scattering equipment, a model for MOR achieved an R² exceeding 0.3. Combinations with average density or outer shape parameters from log scanning resulted in R² 0.4 and 0.3 respectively, although these parameters alone only accounted for R² 0.2. The results can be used to increase the understanding of strength in wood and in an improved industrial strength-grading process.
32.	Brännström, Mattias, et al. (författare) Predicting the strength of sawn wood by tracheid laser scattering 2008 Ingår i: BioResources. - 1930-2126. ; 3:2, s. 437-451 Tidskriftsartikel (refereegranskat)
33.	Brännström, Mattias (författare) The impact of a strength grading process on sawmill profitability and product quality 2009 Ingår i: BioResources. - 1930-2126. ; 4:4, s. 1430-1454 Tidskriftsartikel (refereegranskat)abstract A strength grading process, starting with log grading, was studied with respect to grading yield, impact on quality, and economic efficiency when visual grades according to Nordic grading rules were used for alternate product comparison. Pine (Pinus sylvestris) and spruce (Picea abies) logs and boards were graded with several varieties of commercial grading and strength-grading equipment. The boards were destructively tested, and the European grade-determining properties strength, stiffness, and density were measured. Models for these were made by partial least squares and validated. A method for the derivation of settings for multiple indicating properties, which increased yield in some cases, was proposed and evaluated. Grading to grade combinations of C40, C30, and C18 was done. The impact of visual override based on deformations was also studied. A simplified economic and sensitivity analysis was done. The outcome was that log grading can be used for strength grading with good economic and quality results. Strength pregrading on logs improves sawmill economy, depending on the species and market situation. Drying quality greatly influences the yield through visual override grading on deformations. Market prices of high grades (>C30) must improve in order to stimulate supply, as it is more economical to produce lower grades.
34.	Brännvall, Elisabet (författare) The limits of delignification in kraft cooking 2017 Ingår i: BioResources. - 1930-2126. ; 12:1, s. 2081-2107 Tidskriftsartikel (refereegranskat)abstract The perspective of the article is to explore kraft cooking at the limits of delignification, i.e. what degree of delignification is needed to obtain fibre liberation and what is the maximum degree of delignification possible in the kraft pulping stage. The reasons for the quite narrow boundaries for sufficient and maximum delignification are explained, and the differences between the behaviour of hardwood and softwood kraft pulping are clarified.
35.	Buck, Dietrich, et al. (författare) Bending Properties of Cross Laminated Timber (CLT) with a 45° Alternating Layer Configuration 2016 Ingår i: BioResources. - : BioResources. - 1930-2126. ; 11:2, s. 4633-4644 Tidskriftsartikel (refereegranskat)abstract Bending tests were conducted with cross laminated timber (CLT) panels made using an alternating layer arrangement. Boards of Norway spruce were used to manufacture five-layer panels on an industrial CLT production line. In total, 20 samples were tested, consisting of two CLT configurations with 10 samples of each type: transverse layers at 45° and the conventional 90° arrangement. Sample dimensions were 95 mm × 590 mm × 2000 mm. The CLT panels were tested by four point bending in the main load-carrying direction in a flatwise panel layup. The results indicated that bending strength increased by 35% for elements assembled with 45° layers in comparison with 90° layers. Improved mechanical load bearing panel properties could lead to a larger span length with less material.
36.	Buck, Dietrich, 1990-, et al. (författare) Comparison of Different Assembling Techniques Regarding Cost, Durability, and Ecology - A Survey of Multi-layer Wooden Panel Assembly Load-Bearing Construction Elements 2015 Ingår i: BioResources. - : BioResources. - 1930-2126. ; 10:4, s. 8378-8396 Tidskriftsartikel (refereegranskat)abstract Wood is a pure, sustainable, renewable material. The increasing use of wood for construction can improve its sustainability. There are various techniques to assemble multi-layer wooden panels into prefabricated, load-bearing construction elements. However, comparative market and economy studies are still scarce. In this study, the following assembling techniques were compared: laminating, nailing, stapling, screwing, stress laminating, doweling, dovetailing, and wood welding. The production costs, durability, and ecological considerations were presented. This study was based on reviews of published works and information gathered from 27 leading wood product manufacturing companies in six European countries. The study shows that the various techniques of assembling multi-layer wooden construction panel elements are very different. Cross laminated timber (CLT) exhibited the best results in terms of cost and durability. With regard to ecological concerns, dovetailing is the best. Taking into account both durability and ecological considerations, wooden screw-doweling is the best. These alternatives give manufacturers some freedom of choice regarding the visibility of surfaces and the efficient use of lower-quality timber. CLT is the most cost-effective, is not patented, and is a well-established option on the market today.
37.	Buck, Dietrich, 1990-, et al. (författare) Production and In-Plane Compression Mechanics of Alternatively Angled Layered Cross-Laminated Timber 2018 Ingår i: BioResources. - : University of North Carolina Press. - 1930-2126. ; 13:2, s. 4029-4045 Tidskriftsartikel (refereegranskat)abstract Increasing awareness of sustainable building materials has led to interest in enhancing the structural performance of engineered wood products. This paper reports mechanical properties of cross-laminated timber (CLT) panels constructed with layers angled in an alternative configuration on a modified industrial CLT production line. Timber lamellae were adhesively bonded together in a single-step press procedure to form CLT panels. Transverse layers were laid at an angle of 45°, instead of the conventional 90° angle with respect to the longitudinal layers’ 0° angle. Tests were carried out on 20 five-layered CLT panels divided into two matched groups with either a 45° or a 90° configuration; an in-plane uniaxial compressive loading was applied in the principal orientation of the panels. These tests showed that the 45°-configured panels had a 30% higher compression stiffness and a 15% higher compression strength than the 90° configuration. The results also revealed that the 45°-configured CLT can be industrially produced without using more material than is required for conventional CLT 90° panels. In addition, the design possibility that the 45°-configured CLT can carry a given load while using less material also suggests that it is possible to use CLT in a wider range of structural applications.
38.	Bylin, Susanne, 1982, et al. (författare) Lignin Structure and Aggregation Behavior in a Two-Component Ionic Liquid Solvent System 2014 Ingår i: BioResources. - : BioResources. - 1930-2126 .- 1930-2126. ; 9:4, s. 6002-6018 Tidskriftsartikel (refereegranskat)abstract Ionic liquids are of potential interest in the processing of lignocellulosic biomass. In this study, the ionic liquid co-solvent system of 1-methylimidazole (MIM) and 1-ethyl-3-methyl-imidazolium acetate (EMIMAc) was used to solvate LignoBoost lignin fractionated from black liquor obtained from a kraft paper mill. Lignin ethanol-precipitated (LEP) and ethanol-soluble (LES) fractions were characterized via gel permeation chromatography (GPC) and 13C- and 31P-nuclear magnetic resonance spectroscopy (NMR) to determine structural characteristics and their relationship to polymer solubility in the system. Polymer integrity and solubility were optimal at ~20% lignin loading (w/w). Results showed that LEPs were generally of higher apparent molecular weight (Mw) and enriched with condensed/aliphatic ether linkages and aliphatic hydroxyls. The LESs had a lower apparent Mw and were enriched with carboxylic and phenolic groups. This newly gained knowledge on lignin fractionation and aggregation in the present solvent system provides future opportunities for tuning fractionation/extraction to suit a specific biomass-derived product, e.g., carbon fibers
39.	Bylin, Susanne, 1982, et al. (författare) Solvation behavior of cellulose and xylan in the MIM/EMIMAc ionic liquid solvent system – parameters for small scale solvation 2014 Ingår i: BioResources. - : BioResources. - 1930-2126 .- 1930-2126. ; 9:1, s. 1038-1054 Tidskriftsartikel (refereegranskat)abstract Ionic liquid treatment has been reported by several researchers as a possible step in the process of fractionating lignocellulosic biomass within the biorefinery concept. However, understanding how solvation can be achieved and how the feedstock biopolymers are affected is needed prior to a viable implementation. An effective two component solvent system for the wood components cellulose and xylan has been developed. Furthermore, the solvation of these components in the system consisting of the ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate (EMIMAc) in a novel combination with the co-solvent 1-methylimidazole (MIM) is investigated. Focused beam reflectance measurement (FBRM) particle characterization in combination with microscopic analysis and molecular weight determinations (xylan) shows that cellulose and xylan can be most efficiently solvated using only 3 to 4% IL (n/n anhydro-glucose units and n/n anhydro-xylose units) and 9% IL, respectively, while still avoiding any significant polymer degradation. A model for a two-step process of cellulose solvation in the present system is proposed.
40.	Bäckström, Marie, et al. (författare) The influence of refining heterogeneity on paper properties 2019 Ingår i: BioResources. - : North Carolina State University. - 1930-2126. ; 14:3, s. 6577-6590 Tidskriftsartikel (refereegranskat)abstract This paper studies the impact of refining heterogeneity on paper property development and pressability. Three trials were performed in different refining equipment. The results showed that the strength development was due mostly to the water retention value (WRV) and the fiber straightness. Curly fibers require more energy to reach a given strength property. A heterogeneous refining, which in this case was performed by mixing less refined and highly refined pulps in different proportions, increased the energy requirement to reach a given tensile index or tensile stiffness index. The pressability of the pulps was not affected by the refining heterogeneity. At a given WRV, the pulp had the same solids content after dynamic pressing independent of the degree of heterogeneity.
41.	Bäckström, Marie, et al. (författare) The influence of the counter-ions to the charged groups on the refinability of never- dried bleached pulps 2010 Ingår i: BioResources. - 1930-2126. ; 5:4, s. 2751-2764 Tidskriftsartikel (refereegranskat)abstract Refining of bleached hardwood pulps and bleached softwood pulps having different counter-ions to the charged groups within the fibres was studied. The results show that an energy reduction of 50% for the hardwood pulps and 20% for the softwood pulp can be achieved if the fibres are converted into the Na+-form prior to refining. The results also show that the amount of charged groups in the fibres is important for the refinability, which explains why the refining efficiency is much lower for bleached softwood fibres, which have a much smaller amount of charged groups than the bleached hardwood pulp.
42.	Börjesson, Mikaela, 1987, et al. (författare) Arabinoxylan and Nanocellulose from a Kilogram-scale Extraction of Barley Husk 2019 Ingår i: BioResources. - : BioResources. - 1930-2126 .- 1930-2126. ; 13:3, s. 6201-6220 Tidskriftsartikel (refereegranskat)abstract Processes of extracting hemicellulose from annual plants usually neglect the cellulose fraction. This study explored the possibility of obtaining both a hemicellulose and a cellulose fraction of sufficient quality for further use, with barley husks used as the raw material. An alkaline extraction was used to isolate the biopolymers by a process in which sodium dithionite replaced the traditional sodium borohydride as the reducing agent. The cellulose fraction was successfully transformed into nanocellulose by sulfuric acid hydrolysis, and the obtained hemicellulose (i.e., arabinoxylan) displayed carbohydrate composition characteristics similar to those previously reported in the literature for processes of extracting hemicellulose from barley husks. Using this methodology, both the cellulose and hemicellulose can be isolated in high quantities of dry material and used for transformation into new bio-based materials.
43.	Börjesson, Mikaela, 1987, et al. (författare) UV radiation of cellulose fibers and acrylic acid modified cellulose fibers for improved stiffness in paper 2015 Ingår i: BioResources. - : BioResources. - 1930-2126 .- 1930-2126. ; 10:2, s. 3056-3069 Tidskriftsartikel (refereegranskat)abstract In this study, the strength and stiffness was measured on paper sheets with and without acryl ester functionalization grafted with UV-reactive molecules. Three different monomers with one, two, and three UV-reactive groups, respectively, were reacted with the unsaturated ester. The tri-functional monomer had the most influence on the strength properties of the three monomers and was added in concentrations of 5 to 20 wt% of paper (0.03-0.11 mol eq./AGU). The strength and stiffness properties were measured with tensile tests. An increase in elongation, tensile index, and Young's modulus was seen after irradiation. However, the paper sheets esterified with acrylic acid prior to radiation showed no improvement in stiffness compared to a non-treated paper. As a result, the esterification with acrylic acid to enhance the grafting effect did not have the ability to compensate for the loss in strength caused by the esterification treatment.
44.	Cai, Lili, et al. (författare) Optimization of aluminum/silicon compounds on fire resistance of old corrugated container fiber foam material 2016 Ingår i: BioResources. - : BioResources. - 1930-2126. ; 11:3, s. 6505-6517 Tidskriftsartikel (refereegranskat)abstract Old corrugated container fiber foam material (OCCM) was prepared using a liquid frothing approach. The effect of the content of Al/Si compounds, the molar ratio of Al3+/SiO2, and different addition form on the limited oxygen index (LOI) and residue percentage of OCCM was optimized using an orthogonal design. The fire resistance of OCCM was best when the content of Al/Si compounds was 900 mL, the molar ratio of Al3+/SiO2 was 1:1, and the aluminum sulfate solution was added first, followed by the separately added sodium silicate solution. Under these conditions, the LOI and residue percentage of OCCM reached 32.3 and 53.51%, respectively. Thermogravimetric analysis indicated that Al/Si compounds promoted char formation and reduced the heat release of the optimized OCCMs during depolymerisation. Compared with the control group, the residue percentage of optimized OCCM was increased from 12.49% to 37.98%. Fourier transform infrared spectroscopy identified the functional groups of Al/Si compounds in the optimized OCCMs, confirming that pyrolysis of the optimized OCCMs was affected by Al/Si compounds.
45.	Cai, Lili, et al. (författare) Ultra-Low Density Fibreboard with Improved Fire Retardance and Thermal Stability using a Novel Fire- Resistant Adhesive 2016 Ingår i: BioResources. - : BioResources. - 1930-2126. ; 11:2, s. 5215-5229 Tidskriftsartikel (refereegranskat)abstract A novel fire-resistant adhesive made from polyvinyl alcohol, urea, phosphoric acid, and starch was demonstrated for use as a binder and fire retardant to produce ultra-low density fibreboard (ULDF) with clear environmental benefits. The results from Fourier transform infrared spectroscopy showed the presence of chemical bonding between fire- resistant adhesives and ULDFs. The limiting oxygen index (LOI), combustion behaviour, and thermal stability were characterized using a LOI text, cone calorimeter, and thermal analyzer, respectively. The results demonstrated that the LOI value of the fire-retardant ULDF can reach up to 34.2 with 300 mL of fire-resistant adhesive. It was established that the additive noticeably reduced the peak of heat release rate, total heat release, and total smoke release of ULDF. Their morphologies after combustion were elucidated using a scanning electron microscope, and a char layer in the condensed phase was observed. Thermal analysis showed that the thermal stability of ULDF improved dramatically and the residual weight increased 4-fold, to 48.32%. Therefore, such ULDFs will be tremendously attractive as renewable, sustainable, and bio-based insulating materials.
46.	Chandolias, Konstantinos, 1985-, et al. (författare) Effects of Heavy Metals and pH on the Conversion of Biomass to Hydrogen via Syngas Fermentation 2018 Ingår i: BioResources. - : BioResources. - 1930-2126. ; 13:2, s. 4455-4469 Tidskriftsartikel (refereegranskat)abstract The effects of three heavy metals on hydrogen production via syngas fermentation were investigated within a metal concentration range of 0 to 1.5 mg Cu/L, 0 to 9 mg Zn/L, 0 to 42 mg Mn/L, in media with initial pH of 5, 6, and 7, at 55 degrees C. The results showed that at lower metal concentration, pH 6 was optimum while at higher metal concentrations, pH 5 stimulated the process. More specifically, the highest hydrogen production activity recorded was 155% +/- 12% at a metal concentration of 0.04 mg Cu/L, 0.25 mg Zn/L, and 1.06 mg Mn/L and an initial medium pH of 6. At higher metal concentration (0.625 mg Cu/L, 3.75 mg Zn/L, and 17.5 mg Mn/L), only pH 5 was stimulating for the cells. The results showed that the addition of heavy metals, contained in gasification-derived ash, can improve the production rate and yield of fermentative hydrogen. This could lead to lower costs in gasification process and fermentative hydrogen production and less demand for syngas cleaning before syngas fermentation.
47.	Chen, Tingjie, et al. (författare) Effect of Refining on Physical Properties and Paper Strength of Pinus massoniana and China Fir Cellulose Fibers 2016 Ingår i: BioResources. - : BioResources. - 1930-2126. ; 11:3, s. 7839-7848 Tidskriftsartikel (refereegranskat)abstract To obtain a suitable refining process for Pinus massoniana cellulose fibers (PMCF) and China fir cellulose fibers (CFCF), the effects of the beating gap and the pulp consistency on the physical properties and the morphology of the two cellulose fibers were investigated. The results showed that the physical properties of the PMCF and the CFCF were well affected by the beating gap and the pulp consistency. The CFCF showed a smaller weight-average length and width than that of the PMCF. The CFCF exhibited smaller weight-average length, width, and kink index than the PMCF. It is easy to get the high beating degree, indicating it is more easily to be refined. Additionally, the tensile index and burst index of PMCFP and CFCFP increased with increasing beating degree, while the tear index decreased. Compared to the CFCF, the paper made from PMCF had superior strength properties. Consequently, the PMCF was suitable for refining with a high pulp consistency and a medium beating gap, whereas the CFCF had a medium pulp consistency and a big beating gap.
48.	Chen, Tingjie, et al. (författare) Evaluating the Effectiveness of Complex Fire-Retardants on the Fire Properties of Ultra-low Density Fiberboard (ULDF) 2016 Ingår i: BioResources. - : BioResources. - 1930-2126. ; 11:1, s. 1796-1807 Tidskriftsartikel (refereegranskat)abstract The preparation conditions of complex fire-retardant (FR) agents containing boron compounds (BF, X1), nitrogen-phosphorus compounds (NPF, X2), silicon compounds (SF, X3), and halogen compounds (HF, X4) for ultra-low density fiberboard (ULDF) were optimized using a response surface methodology. The effects and interactions of X1, X2, X3, and X4 on the fire properties of ULDF were investigated. An optimum char yield of 61.4% was obtained when the complex fire-retardant agents contained 33.9% boron, 27.2% nitrogen-phosphorus, 15.0% silicon, and 28.6% halogen. Compared with control fiberboard (CF), the heat release rate (HRR) profiles of all fiberboards with FRs were reduced. The peak HRR reduction in BF and NPF was more pronounced than for SF and HF at this stage. And the mixed fiberboard (MF) had the lowest pkHRR of 75.02 kW m−2. In total heat release (THR) profiles, all fiberboards with FRs were lower than the CF. Unlike the HRR profiles, HF had the lowest THR profile of 15.33 MJ/m−2. Additionally, Si compounds showed greater effectiveness in preventing ULDF mass loss than BF, NPF, and HF. MF showed the highest residual mass (40.94%). Furthermore, the synergistic effect between four FR agents showed more significant results in ULDFs.
49.	Chen, Tingjie, et al. (författare) Improving the Mechanical Properties of Ultra-Low Density Plant Fiber Composite (ULD_PFC) by Refining Treatment 2016 Ingår i: BioResources. - : BioResources. - 1930-2126. ; 11:4, s. 8558-8569 Tidskriftsartikel (refereegranskat)abstract To improve the mechanical properties of ultra-low density plant fiber composite (ULD_PFC), a suitable beating process to improve the fibrillation of cellulose fibers and maintain their length was investigated. The physical properties of cellulose fibers and papers, surface chemical bonds, and internal bond strength (IB) of ULD_PFCs were analyzed. The results showed that the beating degrees, degree of fibrillation, and fiber fines increased with the decreasing of beating gap, except for the fiber weight-average length, width, kink index, and curl index. The tensile index and burst index of paper showed an increasing trend with an increase in beating degree, while the tear index showed a decreasing trend. FTIR results showed that intermolecular and intramolecular hydrogen bonds in ULDF were broken. A suitable beating gap of 30 μm with a beating degree of 35 °SR was obtained. The corresponding IB was 50.9 kPa, which represented an increase of 73.1% over fibers with a beating degree of 13 °SR.
50.	Chen, Tingjie, et al. (författare) Optimizing Refining Conditions of Pinus massoniana Cellulose Fibers for Improving the Mechanical Properties of Ultra-Low Density Plant Fiber Composite (ULD_UFC) 2017 Ingår i: BioResources. - : North Carolina State University. - 1930-2126. ; 12:1, s. 8-18 Tidskriftsartikel (refereegranskat)abstract Response surface methodology was used to optimize the refining conditions of Pinus massoniana cellulose fiber and to improve the mechanical properties of ultra-low density plant fiber composite (ULD_PFC). The effects and interactions of the pulp consistency (X1), the number of passes (X2), and the beating gap (X3) on the internal bond strength of ULD_PFC were investigated. The results showed that the optimum internal bond strength (91.72 ± 2.28 kPa) was obtained under the conditions of 8.0% pulp consistency, two passes through the refiner, and a 30.0 μm beating gap. Analysis of the physical properties of the fibers and handsheets showed that the fibrillation of fibers with optimum refining conditions was improved. Also, the tear index of the optimal specimen was 13.9% and 24.5% higher than specimen-1 with a lowest beating degree of 24 oSR and specimen-6 with a highest beating degree of 73 oSR, respectively. Consequently, the optimal refining conditions of the fibers are valid for preparing ULD_PFCs.

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