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1. Phenol-formaldehyde resins with suitable bonding strength synthesized from “less-reactive” hardwood lignin fractions

Author:
Lourençon, Tainise V.; Alakurtti, Sami; Virtanen, Tommi; Jääskeläinen, Anna-Stiina; Liitiä, Tiina; Hughes, Mark; Magalhães, Washington L.E.; Muniz, Graciela I.B.; Tamminen, Tarja
Source:
Holzforschung 2020 v.74 no.2 pp. 175-183
ISSN:
1437-434X
Subject:
hardwood; hardwood lignin,   etc   ; chemical reactions; formaldehyde; grasses; phenol; phenolic resins; resins; softwood;     Show all 9 Subjects
Abstract:
... The substitution of phenol by lignin in phenol-formaldehyde (PF) resins is one of the most promising end uses of lignin valorization. Lignin from grasses and softwood has been the focus of the studies in this field as they present a higher number of theoretical reactive sites for resin synthesis. Herein we examined the composition and chemical reactivity of “less-reactive” hardwood lignin fraction ...
DOI:
10.1515/hf-2018-0203

2. Early seral pathways of vegetation change following repeated short-interval, high-severity wildfire in a low-elevation, mixed conifer – hardwood forest landscape of the Klamath Mountains, California

Author:
McCord, Millen; Reilly, Matthew J.; Butz, Ramona J.; Jules, Erik S.
Source:
Canadian journal of forest research 2020 v.50 no.1 pp. 13-23
ISSN:
1208-6037
Subject:
hardwood; hardwood forests,   etc   ; altitude; conifers; forbs; graminoids; landscapes; mountains; shrubs; vegetation structure; wildfires; California;     Show all 12 Subjects
Abstract:
... We compared early seral development between stands subject to single and repeated high-severity wildfire in low-elevation, mixed conifer – hardwood forests in the Klamath Mountains, California, USA. We used a before–after, control–impact (BACI) approach to assess changes in the density of conifer regeneration and the cover of multiple components of vegetation structure (conifers, hardwoods, shrubs ...
DOI:
10.1139/cjfr-2019-0161

3. Reduced chemical kinetics for microscale pyrolysis of softwood and hardwood

Author:
Richter, Franz; Rein, Guillermo
Source:
Bioresource technology 2020 v.301 pp. 122619
ISSN:
0960-8524
Subject:
hardwood,   etc   ; models; prediction; pyrolysis; reaction kinetics; softwood; uncertainty;     Show all 7 Subjects
Abstract:
... This work studies the chemical kinetics of wood pyrolysis by comparing nine reduced reaction schemes against 22 microscale experiments of softwood and hardwood from the literature. The complexity of reaction schemes ranged from 1 to 12 reactions, with 2 to 7 species. Using multi-objective optimization for isothermal and non-isothermal conditions, the kinetic parameters for each reaction scheme wer ...
DOI:
10.1016/j.biortech.2019.122619

4. Evolved gas analysis-mass spectrometry and isoconversional methods for the estimation of component-specific kinetic data in wood pyrolysis

Author:
Nardella, Federica; Mattonai, Marco; Ribechini, Erika
Source:
Journal of analytical and applied pyrolysis 2020 v.145 pp. 104725
ISSN:
0165-2370
Subject:
hardwood,   etc   ; activation energy; mass spectrometry; polysaccharides; pyrolysis; softwood;     Show all 6 Subjects
Abstract:
... The pyrolysis reactions of hardwood and softwood were investigated using evolved gas analysis and mass spectrometry (EGA-MS) and by treating the experimental data with isoconversional methods to obtain kinetic information. Mass spectrometric detection allowed the identification of the pyrolysis products to be performed and component-specific thermograms were obtained by the extraction of appropria ...
DOI:
10.1016/j.jaap.2019.104725

5. Enzymatic treatment improves fast pyrolysis product selectivity of softwood and hardwood lignin

Author:
Wang, Lei; Ni, Haoxiang; Zhang, Jialong; Shi, Qipeng; Zhang, Ran; Yu, Hongbo; Li, Mengjie
Source:
The Science of the total environment 2020 v.717 pp. 137241
ISSN:
0048-9697
Subject:
hardwood; hardwood lignin,   etc   ; Ginkgo; Populus; biochar; biomass; biorefining; enzymatic treatment; lignocellulose; pretreatment; pyrolysis; softwood; surface area; temperature; white-rot fungi;     Show all 15 Subjects
Abstract:
... Fast pyrolysis of lignin is still struggling in efficiency and scalable utilization. The low product selectivity thereby represents one of the most challenging issues. White-rot fungi have been widely used in bio-pretreatment of lignocellulosic biomass, where ligninolytic enzymes have been evidenced to modify lignin structures and enhance bio-refining efficiency. We thus treated lignin from both s ...
DOI:
10.1016/j.scitotenv.2020.137241

6. Predicting oak regeneration success at the stem exclusion stage of stand development in upland hardwood forests

Author:
Graboski, Lake E.; Steiner, Kim C.; McDill, Marc E.; Finley, James C.
Source:
Forest ecology and management 2020 v.465 pp. 118093
ISSN:
0378-1127
Subject:
hardwood; hardwood forests,   etc   ; Acer rubrum; Betula lenta; Quercus; environmental impact; highlands; models; prediction; probability; seedlings; stand development; trees; Eastern United States;     Show all 14 Subjects
Abstract:
... Oaks (Quercus spp.) are becoming less abundant in most of the Central Hardwood Region of the eastern United States, and this is creating shifts in forest composition that will likely have important economic and ecological consequences. In large measure, these changes originate with deficiencies in the oak regeneration cohort preceding stand-replacement disturbances such as timber harvest. To susta ...
DOI:
10.1016/j.foreco.2020.118093

7. Hardwood-softwood composition influences early-instar larval dispersal mortality during a spruce budworm outbreak

Author:
Zhang, Bo; MacLean, David A.; Johns, Rob C.; Eveleigh, Eldon S.; Edwards, Sara
Source:
Forest ecology and management 2020 v.463 pp. 118035
ISSN:
0378-1127
Subject:
hardwood; hardwood forests,   etc   ; Abies balsamea; Choristoneura fumiferana; broadleaved trees; defoliation; forest stands; habitat fragmentation; larvae; mixed stands; mortality; natural enemies; parasitism; seedlings; softwood; traps;     Show all 16 Subjects
Abstract:
... Spruce budworm (Choristoneura fumiferana Clem.) defoliation of balsam fir (Abies balsamea (L.) Mill.) has been shown to be less severe in stands with higher hardwood (broadleaved trees) content during both building and declining phases of budworm outbreaks. Reduced defoliation associated with forest composition could be explained by habitat fragmentation and/or natural enemy hypotheses, which posi ...
DOI:
10.1016/j.foreco.2020.118035

8. A welfare analysis of China's tariffs on U.S. hardwood products

Author:
Zhang, Xufang; Haviarova, Eva; Zhou, Mo
Source:
Forest policy and economics 2020 v.113 pp. 102085
ISSN:
1389-9341
Subject:
hardwood,   etc   ; consumer surplus; exports; forest industries; imports; lumber; models; stakeholders; tariffs; China; United States;     Show all 11 Subjects
Abstract:
... China has been the top importer of U.S. log and lumber since 2010. With the ongoing trade disputes between the U.S. and its trading partners, especially with China, it is of great interest to assess the potential impacts of different trade interventions on U.S. forest sector. In this study, we focus on hypothetical uniform tariffs by China on U.S. hardwood products in four scenarios: tariffs impos ...
DOI:
10.1016/j.forpol.2019.102085

9. Analysis of pyrolysis reactor for hardwood (Acacia) chips

Author:
Dhaundiyal, Alok; Toth, Laszlo; Bacskai, Istvan; Atsu, Divine
Source:
Renewable energy 2020 v.147 pp. 1979-1989
ISSN:
0960-1481
Subject:
hardwood,   etc   ; Acacia; biomass; energy; heat transfer; producer gas; pyrolysis; renewable energy sources; temperature;     Show all 9 Subjects
Abstract:
... This work investigates the designing aspect of a pyrolysis reactor. The reactor is operated within a temperature interval of 292 K–637 K. The pressure of the generated gas varies from 4 Pa to 26.8 Pa during the whole pyrolysis process. The assessment of reactor is based upon the gas dynamic of generated gas, and the effect of heat transfer on the energy generation. The dimension of reactor used fo ...
DOI:
10.1016/j.renene.2019.09.095

10. The effect of the carboxylation degree on cellulose nanofibers and waterborne polyurethane/cellulose nanofiber nanocomposites properties

Author:
Larraza, Izaskun; Vadillo, Julen; Santamaria-Echart, Arantzazu; Tejado, Alvaro; Azpeitia, Maider; Vesga, Eneritz; Orue, Ander; Saralegi, Ainara; Arbelaiz, Aitor; Eceiza, Arantxa
Source:
Polymer degradation and stability 2020 v.173 pp. 109084
ISSN:
0141-3910
Subject:
hardwood,   etc   ; carboxylation; cellulose; cellulose nanofibers; crystal structure; hydrophilicity; kraft pulp; mechanical properties; nanocomposites; polyurethanes; thermal stability;     Show all 11 Subjects
Abstract:
... There has been an exponential rise in the interest for waterborne polyurethanes (WBPU), due to the easy customizability of their properties and their ecofriendly nature. Moreover, their aqueous state facilitates the incorporation of hydrophilic reinforcements. Cellulose nanofibers (CNFs) have shown great potential, thanks to their renewability, large natural availability, low cost and great specif ...
DOI:
10.1016/j.polymdegradstab.2020.109084

11. Influence of forest harvest severity and time since perturbation on conservation of North American birds

Author:
Twedt, Daniel J.
Source:
Forest ecology and management 2020 v.458 pp. 117742
ISSN:
0378-1127
Subject:
hardwood forests,   etc   ; birds; coniferous forests; conservation status; forest stands; wildlife management; North America;     Show all 7 Subjects
Abstract:
... I calculated avian conservation scores, based on published quantitative assessment of bird presence (typically relative abundance) and regional Partners in Flight conservation concern score of each species. I related these avian conservation scores to severity of forest perturbation (i.e., % retention) and number of years since perturbation for forest stands within North America. I characterized a ...
DOI:
10.1016/j.foreco.2019.117742

12. Kinetic investigation of dilute acid hydrolysis of hardwood pulp for microcrystalline cellulose production

Author:
Yavorov, Nikolay; Valchev, Ivo; Radeva, Greta; Todorova, Desislava
Source:
Carbohydrate research 2020 v.488 pp. 107910
ISSN:
0008-6215
Subject:
hardwood,   etc   ; acid hydrolysis; activation energy; cellulose; equations; furfural; glucose; kinetics; kraft pulp; polymerization; sulfuric acid; xylose;     Show all 12 Subjects
Abstract:
... This work presents a kinetic investigation of dilute sulfuric acid hydrolysis of bleached hardwood kraft pulp. The temperature-time dependence shows fast xylose extraction during the initial period of the process, while the glucose content increases slowly and permanently over the period. A conversion of xylose into furfural and furfural-derived chromophores is observed. It is established that onl ...
DOI:
10.1016/j.carres.2020.107910

13. Fractionation by Sequential Antisolvent Precipitation of Grass, Softwood, and Hardwood Lignins Isolated Using Low-Cost Ionic Liquids and Water

Author:
Chambon, Clementine L.; Fitriyanti, Vivi; Verdía, Pedro; Yang, Shirley Min; Hérou, Servann; Titirici, Maria-Magdalena; Brandt-Talbot, Agnieszka; Fennell, Paul S.; Hallett, Jason P.
Source:
ACS sustainable chemistry & engineering 2020 v.8 no.9 pp. 3751-3761
ISSN:
2168-0485
Subject:
hardwood; hardwood lignin,   etc   ; Miscanthus; differential scanning calorimetry; fractionation; gel chromatography; grasses; hydrogen; ionic liquids; isolation techniques; molecular weight; nuclear magnetic resonance spectroscopy; quantum mechanics; softwood; sulfates; thermal stability; thermogravimetry;     Show all 17 Subjects
Abstract:
... In this study, fractionation by sequential antisolvent precipitation was applied to ionoSolv lignins for the first time. Pretreatment with the aqueous low-cost protic ionic liquid N,N-dimethylbutylammonium hydrogen sulfate ([DMBA][HSO₄], 80 wt % in water) was applied to Miscanthus (herbaceous), willow (hardwood), and pine (softwood) to extract lignin. Then, lignin was sequentially precipitated by ...
DOI:
10.1021/acssuschemeng.9b06939

14. Persistent anthropogenic legacies structure depth dependence of regenerating rooting systems and their functions

Author:
Hauser, Emma; Richter, Daniel D.; Markewitz, Daniel; Brecheisen, Zachary; Billings, Sharon A.
Source:
Biogeochemistry 2020 v.147 no.3 pp. 259-275
ISSN:
0168-2563
Subject:
hardwood; hardwood forests,   etc   ; Anthropocene epoch; aboveground biomass; carbon; carbon sinks; ecosystems; extracellular enzymes; exudation; fine roots; forest regeneration; forest soils; land use; nutrients; root systems; rooting; soil carbon; soil nutrients; trees; weathering;     Show all 20 Subjects
Abstract:
... Biotically-mediated weathering helps to shape Earth’s surface. For example, plants expend carbon (C) to mobilize nutrients in forms whose relative abundances vary with depth. It thus is likely that trees’ nutrient acquisition strategies—their investment in rooting systems and exudates—may function differently following disturbance-induced changes in depth of rooting zones and soil nutrient stocks. ...
DOI:
10.1007/s10533-020-00641-2

15. Properties of common tropical hardwoods for fretboard of string instruments

Author:
Liu, Meihong; Peng, Limin; Lyu, Shaoyi; Lyu, Jianxiong
Source:
Journal of wood science 2020 v.66 no.1 pp. 14
ISSN:
1435-0211
Subject:
hardwood,   etc   ; Acacia melanoxylon; aesthetics; bending strength; cell walls; color; colorimetry; dimensional stability; hardness; modulus of rupture; texture; trees; water uptake;     Show all 13 Subjects
Abstract:
... Fretboards of string instruments are usually made of rare woods that commonly have a high density, strength, and hardness; further, they are wear resistant, uniform in texture, and feature an elegant color. To reduce the consumption of scarce timber resources, especially of endangered tropical hardwood species, suitable replacement materials should be identified. The substitute can be either commo ...
DOI:
10.1186/s10086-020-01862-7

16. Fuel dynamics and its implication to fire behavior in loblolly pine-dominated stands after southern pine beetle outbreak

Author:
Xie, Hongtao; Fawcett, Jennifer E.; Wang, G. Geoff
Source:
Forest ecology and management 2020 v.466 pp. 118130
ISSN:
0378-1127
Subject:
hardwood,   etc   ; Dendroctonus frontalis; Pinus; fire behavior; forests; fuel bed; fuel loading; fuels; stand structure; wildfires; Georgia; South Carolina;     Show all 12 Subjects
Abstract:
... Southern pine beetle (SPB) (Dendroctonus frontalis Zimm) outbreaks and wildfire occurrence in recent decades has triggered growing concerns regarding their possible interactions. However, few studies have quantified the fuel characteristics of SPB-killed stands, especially the dynamics of the resulting fuel complex. More importantly, how changes in the fuel complex will affect fire behavior remain ...
DOI:
10.1016/j.foreco.2020.118130

17. Environmental issues of pulp bleaching and prospects of peracetic acid pulp bleaching: A review

Author:
Sharma, Nirmal; Bhardwaj, Nishi K.; Singh, Ram Bhushan Prashad
Source:
Journal of cleaner production 2020 v.256 pp. 120338
ISSN:
0959-6526
Subject:
hardwood,   etc   ; bleaching; bleaching agents; chlorine; environmental law; markets; paper; peracetic acid; pulp; pulp and paper industry; toxic substances;     Show all 11 Subjects
Abstract:
... To meet the demand of pulp and paper as well as the environmental legislation the pulp production with eco-friendly approach is desired. This paper presented the state of affairs of Indian and world pulp and paper industry. It also reviewed the discharge of toxic substances from pulp bleaching process and the alternatives for reduction of these toxic substances from pulp bleaching process. The pul ...
DOI:
10.1016/j.jclepro.2020.120338

18. Elucidating nano and meso-structures of lignin carbon composites: A comprehensive study of feedstock and temperature dependence

Author:
García-Negrón, Valerie; Kizzire, Dayton G.; Rios, Orlando; Keffer, David J.; Harper, David P.
Source:
Carbon 2020 v.161 pp. 856-869
ISSN:
0008-6223
Subject:
hardwood,   etc   ; Panicum virgatum; X-radiation; bio-feedstocks; carbon; crystallites; energy; environmental factors; furnaces; grasses; humidity; lignin; softwood; statistical analysis; temperature;     Show all 15 Subjects
Abstract:
... The production of carbon materials from renewable biofeedstocks is rapidly expanding with commercial applications in the areas of advanced materials, energy storage, and biochemicals. Present-day challenges exist in understanding how the distribution of monomeric units in lignin feedstocks impacts the structure and properties of carbon composites as a function of processing. This research investig ...
DOI:
10.1016/j.carbon.2020.02.010

19. Evaluation of charcoal ash nanoparticles pollutant removal capacity from acid mine drainage rich in iron and sulfate

Author:
Kefeni, Kebede Keterew; Mamba, Bhekie Brilliance
Source:
Journal of cleaner production 2020 v.251 pp. 119720
ISSN:
0959-6526
Subject:
hardwood,   etc   ; acid mine drainage; adsorption; carbonates; charcoal; crushing; iron; limestone; minerals; nanoparticles; neutralization; oxides; pollutants; pollution; purchasing; remediation; sulfates; toxicity;     Show all 18 Subjects
Abstract:
... Acid mine drainage is globally recognized as one of the environmental pollutants, due to its highly toxic metals and sulfate concentration. In this study, the effect of metal and sulfate removal capacity of Namibian hardwood charcoal ash from acid mine drainage was investigated. The experimental results have shown that charcoal ash has dual pollutant removal capacity via adsorption and precipitati ...
DOI:
10.1016/j.jclepro.2019.119720

20. Characteristics of ash formation in the process of combustion of pelletised leather tannery waste and hardwood pellets

Author:
Kluska, Jacek; Turzyński, Tomasz; Ochnio, Mateusz; Kardaś, Dariusz
Source:
Renewable energy 2020 v.149 pp. 1246-1253
ISSN:
0960-1481
Subject:
hardwood,   etc   ; ash content; combustion; fuel bed; fuels; heat; leather; pellets; renewable energy sources; tannery waste; temperature; thermal degradation; thermogravimetry;     Show all 13 Subjects
Abstract:
... This paper presents a characterisation of the combustion of mixtures of pelletised leather tannery waste (LTW) and hardwood pellets (HP) on a grate. The experimental investigation was carried out in a laboratory-scale combustion reactor with the use of thermogravimetric analysis (TGA). Proximate and ultimate analysis showed that leather tannery waste may constitute a promising fuel, with a relativ ...
DOI:
10.1016/j.renene.2019.10.122