WorldWideScience

Sample records for stabilized engineered wood

  1. Wood handbook : wood as an engineering material

    Science.gov (United States)

    Robert J. Ross; Forest Products Laboratory. USDA Forest Service.

    2010-01-01

    Summarizes information on wood as an engineering material. Presents properties of wood and wood-based products of particular concern to the architect and engineer. Includes discussion of designing with wood and wood-based products along with some pertinent uses.

  2. Effects of phosphoramides on wood dimensional stability

    Science.gov (United States)

    Hong-Lin. Lee; George C. Chen; Roger M. Rowell

    2000-01-01

    To evaluate the dimensional stability of phosphoramide-reacted wood, wood was reacted with a mixture which was derived from compounding phosphorus pentoxide and each of 12 amines including alkyl, halophenyl, and phenyl amines in N,N-dimethylformamide. Dimensional stability of such reacted wood was analyzed by antishrink efficiency (ASE) using the water-soak method....

  3. The effect of wood extractives on the thermal stability of different wood species

    Energy Technology Data Exchange (ETDEWEB)

    Shebani, A.N.; Reenen, A.J. van [Department of Chemistry and Polymer Science, University of Stellenbosch, Private Bag X1, Matieland 7602 (South Africa); Meincken, M. [Department of Forest and Wood Science, University of Stellenbosch, Private Bag X1, Matieland 7602 (South Africa)], E-mail: mmein@sun.ac.za

    2008-05-30

    This study compares the thermal stability of different wood species, which is an important factor for the production of wood-polymer composites (WPCs), and investigates the effect of extraction on thermal properties. The chemical composition of four wood species -Quercus alba, Pinus radiata, Eucalyptus grandis and Acacia cyclops - has been determined, as the species is expected to affect the thermal stability of wood. Subsequently, the hot-water (HW) extractives, ethanol/cyclohexane (E/C) extractives and both extractives were eliminated from the wood via Soxhlet extraction and the thermal stability of the wood determined with thermogravimetric analysis (TGA) under identical conditions. The results suggest that a higher cellulose and lignin content leads to better thermal stability of wood in different temperature regimes. In all cases, the removal of extractives improved the thermal stability of the wood. The effect of combined extractions was more pronounced than of an individual extraction and E/C-extraction caused less improvement in the thermal stability of wood than HW extraction. The degradation of the investigated wood extractives occurred at low rates over a broad temperature range. Pure cellulose exhibited superior thermal stability compared to wood, but differences were observed between the investigated wood species.

  4. Volatile organic compound emissions from engineered wood products

    Science.gov (United States)

    Steve Zylkowski; Charles Frihart

    2017-01-01

    Thirteen bonded engineered wood products representing those commonly used in building construction were evaluated for volatile organic chemicals using methods developed for interior bonded wood products. Although formaldehyde and acetaldehyde were emitted from all samples, they were not the dominant volatiles, which greatly depended on wood species and bonding...

  5. Wood pyrolysis oil for diesel engines

    Energy Technology Data Exchange (ETDEWEB)

    Paro, D.; Gros, S.; Hellen, G.; Jay, D.; Maekelae, T.; Rantanen, O.; Tanska, T. [Wartsila Diesel International Ltd Oy, Vaasa (Finland)

    1996-12-01

    Wood Pyrolysis oil (WPO) has been identified by the Technical Research Centre of Finland (VTT) as the most competitive biofuel product which can be produced from biomass. The fuel is produced by a fast pyrolysis technique, using wood chipping`s or sawdust. The process can be applied to other recycling products such as straw etc. The use of WPO as a Diesel power plant fuel has been studied, and a fuel specification has been developed. The fuel characteristics have been analysed. There are several fuel properties addressed in the paper which have had to be overcome. New materials have been used in the fuel injection system. The fuel injection system development has progressed from a pump-line-pipe system to a common rail system. The fuel requires a pilot fuel oil injection to initiate combustion. The targets for the fuel injection system have been 1500 bar and 30 deg C injection period with a fuel of 15 MJ/kg lower heating value and 1220 Kg/m{sup 3} density. The combustion characteristics from both a small 80 mm bore engine initially, and then later with a single cylinder test of a 320 mm bore Waertsilae engine, have been evaluated. (author)

  6. Wood durability and stability without toxicity

    Science.gov (United States)

    Roger M. Rowell; Rebecca E. Ibach; Thomas Nilsson

    2010-01-01

    Part of a sustainable future for wood products depends on extending the lifetime of wood used in adverse environments. For some products such as the daily news paper, the average life of the products is one day. For packaging, the products average life time may be as few days to a few weeks. For pallets and wooden containers, the lifetime may be several months. For...

  7. Method of stabilizing wood or lignocellulose materials

    International Nuclear Information System (INIS)

    Pesek, M.

    1973-01-01

    Wood or lignocellulose materials are impregnated with vinyl or allyl monomers and unsaturated polyester resins or with modified epoxy, alkyd or polyurethane resins in a mixture. The mixture contains chemical initiators of polymerization - organic peroxides or peroxyesters in an amount of 3 % max. Polymerization is effected by ionizing radiation. (B.S.)

  8. Wood properties from roundwood to timber engineering

    NARCIS (Netherlands)

    van de Kuilen, J.W.G.; Eberhardsteiner, J.; Winter, W.; Fadai, A.; Pöll, M.

    2016-01-01

    Measuring and assessing wood properties during the production chain is getting more and more important for an optimal use of the resource. Over the years, research has been performed with the focus on establishing important wood properties, with the final goal of an

  9. Adoption of engineered wood products in Alaska

    Science.gov (United States)

    Joseph A. Roos; Indroneil Ganguly; Allen Brackley

    2009-01-01

    Based on an in-grade testing program, the Ketchikan Wood Technology Center has registered three proprietary grademarks for Alaska species of hemlock (Tsuga heterophylla (Raf.) Sarg.), yellow-cedar (Chamaecyparis nootkatensis (D. Don) Spach), and spruce (combined Sitka spruce [Picea sitchensis (Bong.) Carr...

  10. OSB as substrate for engineered wood flooring

    Science.gov (United States)

    Costel Barbuta; Pierre Blanchet; Alain Cloutier; Vikram Yadama; Eini. Lowell

    2012-01-01

    Oriented strand board (OSB) is a commodity product subject to market fluctuation. Development of a specialty OSB could lead to a better, and more stable, market segment for OSB. It was demonstrated in a previous study (Barbuta et al. in Eur. 1. Wood Prod. 2010), that OSB may be designed to obtain a high bending modulus of elasticity in the parallel direction, close to...

  11. Engineering Biodegradable Flame Retardant Wood-Plastic Composites

    Science.gov (United States)

    Zhang, Linxi

    Wood-plastic composites (WPCs), which are produced by blending wood and polymer materials, have attracted increasing attentions in market and industry due to the low cost and excellent performance. In this research, we have successfully engineered WPC by melt blending Polylactic Acid (PLA) and Poly(butylene adipate-co-terphthalate) (PBAT) with recycled wood flour. The thermal property and flammability of the composite are significantly improved by introducing flame retardant agent resorcinol bis(biphenyl phosphate) (RDP). The mechanical and morphological properties are also investigated via multiple techniques. The results show that wood material has increased toughness and impact resistance of the PLA/PBAT polymer matrix. SEM images have confirmed that PLA and PBAT are immiscible, but the incompatibility is reduced by the addition of wood. RDP is initially dispersed in the blends evenly. It migrates to the surface of the sample after flame application, and serves as a barrier between the fire and underlying polymers and wood mixture. It is well proved in the research that RDP is an efficient flame retardant agent in the WPC system.

  12. Ongoing evaluation of sources and factors affecting emissions from engineered wood products

    Energy Technology Data Exchange (ETDEWEB)

    Turner, S.L.; Martin, C.B.; Sheldon, L.S.; Baskir, J.N.; Howard, E.M.

    1998-09-01

    The paper describes an ongoing evaluation of sources and factors affecting emissions from engineered wood products. It summarizes early results from emissions testing of engineered wood products. These tests have shown the emissions of volatile organic compounds (VOCs) from the alcohol, aldehyde/ketone, ester, aromatic and aliphatic hydrocarbon, monoterpene, sesquiterpene, indene, and alkyl ether chemical families from engineered wood samples. This information will be used to target pollution prevention approaches, such as alternate materials and production technologies for raw board and engineered wood products, for reducing VOC emissions.

  13. Ethanol production from wood hydrolysate using genetically engineered Zymomonas mobilis.

    Science.gov (United States)

    Yanase, Hideshi; Miyawaki, Hitoshi; Sakurai, Mitsugu; Kawakami, Akinori; Matsumoto, Mari; Haga, Kenji; Kojima, Motoki; Okamoto, Kenji

    2012-06-01

    An ethanologenic microorganism capable of fermenting all of the sugars released from lignocellulosic biomass through a saccharification process is essential for secondary bioethanol production. We therefore genetically engineered the ethanologenic bacterium Zymomonas mobilis such that it efficiently produced bioethanol from the hydrolysate of wood biomass containing glucose, mannose, and xylose as major sugar components. This was accomplished by introducing genes encoding mannose and xylose catabolic enzymes from Escherichia coli. Integration of E. coli manA into Z. mobilis chromosomal DNA conferred the ability to co-ferment mannose and glucose, producing 91 % of the theoretical yield of ethanol within 36 h. Then, by introducing a recombinant plasmid harboring the genes encoding E. coli xylA, xylB, tal, and tktA, we broadened the range of fermentable sugar substrates for Z. mobilis to include mannose and xylose as well as glucose. The resultant strain was able to ferment a mixture of 20 g/l glucose, 20 g/l mannose, and 20 g/l xylose as major sugar components of wood hydrolysate within 72 h, producing 89.8 % of the theoretical yield. The recombinant Z. mobilis also efficiently fermented actual acid hydrolysate prepared from cellulosic feedstock containing glucose, mannose, and xylose. Moreover, a reactor packed with the strain continuously produced ethanol from acid hydrolysate of wood biomass from coniferous trees for 10 days without accumulation of residual sugars. Ethanol productivity was at 10.27 g/l h at a dilution rate of 0.25 h(-1).

  14. Life cycle inventory of manufacturing prefinished engineered wood flooring in eastern U.S. with comparison to solid strip wood flooring

    Science.gov (United States)

    Richard D. Bergman; Scott A. Bowe

    2011-01-01

    Building products have come under increased scrutiny because of environmental impacts from their manufacture. Our study followed the life cycle inventory approach for prefinished engineered wood flooring in the eastern US and compared the results with those of solid strip wood flooring. Our study surveyed five engineered wood flooring manufacturers in the eastern US....

  15. Understanding decay resistance, dimensional stability and strength changes in heat treated and acetylated wood

    Science.gov (United States)

    Roger M. Rowell; Rebecca E. Ibach; James McSweeny; Thomas Nilsson

    2009-01-01

    Reductions in hygroscopicity, increased dimensional stability and decay resistance of heat-treated wood depend on decomposition of a large portion of the hemicelluloses in the wood cell wall. In theory, these hemicelluloses are converted to small organic molecules, water and volatile furan-type intermediates that can polymerize in the cell wall. Reductions in...

  16. Improvement of water resistance and dimensional stability of wood through titanium dioxide coating

    Science.gov (United States)

    Qingfeng Sun; Haipeng Yu; Yixing Liu; Jian Li; Yun Lu; John F. Hunt

    2010-01-01

    Moisture absorption and dimensional distortion are the major drawbacks of wood utilization as building material. In this study, poplar wood coated with a thin layer of titanium dioxide (TiO2) was prepared by the cosolvent-controlled hydrothermal method. Subsequently, its moisture absorption and dimensional stability were examined. Scanning...

  17. Exploiting sequence and stability information for directing nanobody stability engineering.

    Science.gov (United States)

    Kunz, Patrick; Flock, Tilman; Soler, Nicolas; Zaiss, Moritz; Vincke, Cécile; Sterckx, Yann; Kastelic, Damjana; Muyldermans, Serge; Hoheisel, Jörg D

    2017-09-01

    Variable domains of camelid heavy-chain antibodies, commonly named nanobodies, have high biotechnological potential. In view of their broad range of applications in research, diagnostics and therapy, engineering their stability is of particular interest. One important aspect is the improvement of thermostability, because it can have immediate effects on conformational stability, protease resistance and aggregation propensity of the protein. We analyzed the sequences and thermostabilities of 78 purified nanobody binders. From this data, potentially stabilizing amino acid variations were identified and studied experimentally. Some mutations improved the stability of nanobodies by up to 6.1°C, with an average of 2.3°C across eight modified nanobodies. The stabilizing mechanism involves an improvement of both conformational stability and aggregation behavior, explaining the variable degree of stabilization in individual molecules. In some instances, variations predicted to be stabilizing actually led to thermal destabilization of the proteins. The reasons for this contradiction between prediction and experiment were investigated. The results reveal a mutational strategy to improve the biophysical behavior of nanobody binders and indicate a species-specificity of nanobody architecture. This study illustrates the potential and limitations of engineering nanobody thermostability by merging sequence information with stability data, an aspect that is becoming increasingly important with the recent development of high-throughput biophysical methods. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  18. Engineering economic assessment of residential wood heating in NY

    Science.gov (United States)

    We provide insight into the recent resurgence in residential wood heating in New York by: (i) examining the lifetime costs of outdoor wood hydronic heaters (OWHHs) and other whole-house residential wood heat devices,(ii) comparing these lifetime costs with those of competing tech...

  19. Purdue Plane Structures Analyzer II : a computerized wood engineering system

    Science.gov (United States)

    S. K. Suddarth; R. W. Wolfe

    1984-01-01

    The Purdue Plane Structures Analyzer (PPSA) is a computer program developed specifically for the analysis of wood structures. It uses recognized analysis procedures, in conjunction with recommendations of the 1982 National Design Specification for Wood Construction, to determine stresses and deflections of wood trusses and frames. The program offers several options for...

  20. Engineering report (conceptual design) PFP solution stabilization

    International Nuclear Information System (INIS)

    Witt, J.B.

    1997-01-01

    This Engineering Report (Conceptual Design) addresses remediation of the plutonium-bearing solutions currently in inventory at the Plutonium Finishing Plant (PFP). The recommendation from the Environmental Impact Statement (EIS) is that the solutions be treated thermally and stabilized as a solid for long term storage. For solutions which are not discardable, the baseline plan is to utilize a denitration process to stabilize the solutions prior to packaging for storage

  1. Engineering report (conceptual design) PFP solution stabilization

    Energy Technology Data Exchange (ETDEWEB)

    Witt, J.B.

    1997-07-17

    This Engineering Report (Conceptual Design) addresses remediation of the plutonium-bearing solutions currently in inventory at the Plutonium Finishing Plant (PFP). The recommendation from the Environmental Impact Statement (EIS) is that the solutions be treated thermally and stabilized as a solid for long term storage. For solutions which are not discardable, the baseline plan is to utilize a denitration process to stabilize the solutions prior to packaging for storage.

  2. Wood

    DEFF Research Database (Denmark)

    Unterrainer, Walter

    2014-01-01

    come from? How is it harvested? How is it manufactured and treated ? How are the buildings detailed and protected against weather during construction to keep them dry and make them long-life ? In a period of climate change, forests are the last lungs of the planet to sequestrate CO2. Their global size......Wood – a sustainable building material ? For thousands of years and all over the planet, wood has been used as a building material and exciting architecture has been created in wood. The fantastic structural, physical and aesthetic properties of the material as well as the fact that wood...... is a renewable resource makes it predestinated for what is considered ´sustainable architecture´. But the reality is less linear and there are serious traps: In fact the lecture shows by examples that it is much easier to build very unsustainable buildings in wood than the other way round! Where does the wood...

  3. Energy Engineering Analysis Program Study, Fort Leonard Wood, Missouri. Volume 3, Appendices G and H

    National Research Council Canada - National Science Library

    1993-01-01

    ...) Energy Saving Opportunity Survey (ESOS) at Fort Leonard Wood, Missouri. This study was authorized under the contract DACA41-92-C-0098 with Corps of Engineers Kansas City District, Kansas City, Missouri...

  4. Investigation on stability and moisture absorption of superhydrophobic wood under alternating humidity and temperature conditions

    Science.gov (United States)

    Qing, Yan; Liu, Ming; Wu, Yiqiang; Jia, Shanshan; Wang, Shuang; Li, Xingong

    The application of superhydrophobic wood is majorly limited by its durability when subjected to natural conditions. Herein, the stability of two representative superhydrophobic woods (i.e., Poplar (Populus tomentosa) and Chinese fir (Cunninghamia lanceolata)), were prepared via a one-step hydrothermal process using tetrabutyltitanate (Ti(OC4H9)4, TBOT) and vinyltriethoxysilane (CH2CHSi(OC2H5)3, VTES) as a co-precursor and sequentially tested under different humidity and temperature conditions. The variables including morphology, water contact angle (WCA), color parameter, chemical components of the surface, and moisture absorption property were characterized using a scanning electron microscope (SEM), WCA measurement, a colorimeter, a Fourier transform infrared (FTIR) spectroscopy, and a moisture absorption test, respectively. It was found that initial static WCAs of superhydrophobic wood were larger than 150°. Micron-sized cracks were formed on the coatings after the alternating humidity and temperature aging cycles. This lowered the water repellency, but the WCA was still greater than 140°. There was nearly no chemical change of wood after the aging test; the color change between the same species of untreated and superhydrophobic wood was very small, only with a difference of 0.42 and 4.05 in overall color change ΔE∗ values for Chinese fir and poplar, respectively. The superhydrophobic coatings had a trivial influence on wood moisture absorption property, which only lowered 3% in poplar and 2% in Chinese fir, respectively.

  5. Wood

    Science.gov (United States)

    David W. Green; Robert H. White; Antoni TenWolde; William Simpson; Joseph Murphy; Robert J. Ross; Roland Hernandez; Stan T. Lebow

    2006-01-01

    Wood is a naturally formed organic material consisting essentially of elongated tubular elements called cells arranged in a parallel manner for the most part. These cells vary in dimensions and wall thickness with position in the tree, age, conditions of growth, and kind of tree. The walls of the cells are formed principally of chain molecules of cellulose, polymerized...

  6. Thermal stability engineering of Glomerella cingulata cutinase.

    Science.gov (United States)

    Chin, Iuan-Sheau; Abdul Murad, Abdul Munir; Mahadi, Nor Muhammad; Nathan, Sheila; Abu Bakar, Farah Diba

    2013-05-01

    Cutinase has been ascertained as a biocatalyst for biotechnological and industrial bioprocesses. The Glomerella cingulata cutinase was genetically modified to enhance its enzymatic performance to fulfill industrial requirements. Two sites were selected for mutagenesis with the aim of altering the surface electrostatics as well as removing a potentially deamidation-prone asparagine residue. The N177D cutinase variant was affirmed to be more resilient to temperature increase with a 2.7-fold increase in half-life at 50°C as compared with wild-type enzyme, while, the activity at 25°C is not compromised. Furthermore, the increase in thermal tolerance of this variant is accompanied by an increase in optimal temperature. Another variant, the L172K, however, exhibited higher enzymatic performance towards phenyl ester substrates of longer carbon chain length, yet its thermal stability is inversely affected. In order to restore the thermal stability of L172K, we constructed a L172K/N177D double variant and showed that these two mutations yield an improved variant with enhanced activity towards phenyl ester substrates and enhanced thermal stability. Taken together, our study may provide valuable information for enhancing catalytic performance and thermal stability in future engineering endeavors.

  7. Advancing sustainable forestry by using engineered wood or bio-composites

    Science.gov (United States)

    Jerrold E. Winandy

    2005-01-01

    As worldwide demand for timber and bio-fiber resources grows, sustainable resource management and industrial utilization must collaborate to develop a shared vision for both long-term sustainable management of forest and bio-resources and sustainable economic development. Engineered wood- and bio-composites offer a tool that can both achieve resource sustainability and...

  8. Slope stabilization guide for Minnesota local government engineers.

    Science.gov (United States)

    2017-06-01

    This user guide provides simple, costeffective methods for stabilizing locally maintained slopes along roadways in Minnesota. Eight slope stabilization techniques are presented that local government engineers can undertake using locally available ...

  9. Integration of a wood pellet burner and a Stirling engine to produce residential heat and power

    International Nuclear Information System (INIS)

    Cardozo, Evelyn; Erlich, Catharina; Malmquist, Anders; Alejo, Lucio

    2014-01-01

    The integration a Stirling engine with a pellet burner is a promising alternative to produce heat and power for residential use. In this context, this study is focused on the experimental evaluation of the integration of a 20 kW th wood pellet burner and a 1 kW e Stirling engine. The thermal power not absorbed by the engine is used to produce hot water. The evaluation highlights the effects of pellet type, combustion chamber length and cycling operation on the Stirling engine temperatures and thermal power absorbed. The results show that the position of the Stirling engine is highly relevant in order to utilize as much as possible of the radiative heat from the burner. Within this study, only a 5 cm distance change between the Stirling engine and the pellet burner could result in an increase of almost 100 °C in the hot side of the engine. However, at a larger distance, the temperature of the hot side is almost unchanged suggesting dominating convective heat transfer from the hot flue gas. Ash accumulation decreases the temperature of the hot side of the engine after some cycles of operation when a commercial pellet burner is integrated. The temperature ratio, which is the relation between the minimum and maximum temperatures of the engine, decreases when using Ø8 mm wood pellets in comparison to Ø6 mm pellets due to higher measured temperatures on the hot side of the engine. Therefore, the amount of heat supplied to the engine is increased for Ø8 mm wood pellets. The effectiveness of the engine regenerator is increased at higher pressures. The relation between temperature of the hot side end and thermal power absorbed by the Stirling engine is nearly linear between 500 °C and 660 °C. Higher pressure inside the Stirling engine has a positive effect on the thermal power output. Both the chemical and thermal losses increase somewhat when integrating a Stirling engine in comparison to a stand-alone boiler for only heat production. The overall efficiency

  10. Fort Leonard Wood Culvert and Flagpole: Historic American Engineering Record

    Science.gov (United States)

    2011-04-18

    design contained 20 barracks, four latrines, four mess halls, one canteen , one administration barracks, one recreation room, one theater, one...remain the same. The cantonment continues to grow as the Army Chemical and Military Police Schools were relocated to FLW in 1999-2000...Original Use: Army Engineer Training Center Present Use: US Army Engineer School (USAES), US Army Chemical School (USACS), US Army Military Police

  11. Laminated wood as an alternative to wood poles : Engineered wood structures for electric utility and telecommunications industries

    Energy Technology Data Exchange (ETDEWEB)

    Reisdorff, R. [Laminated Wood Systems Inc., Seward, NE (United States)

    2002-07-01

    In this PowerPoint presentation, the author discusses the major advantages of laminated structures, for both the electric and telecommunication industries. The advantages include economy, quick delivery, climbing and field modifications, dimensional uniformity and stability. A series of pictures was displayed which showed the manufacturing process. Laminated structures have a proven history. They were developed in Europe in 1890, and introduced to the United States in 1934. Framing members were introduced in the late 1940s, while poles were introduced in 1963, two years ahead of steel poles. Some of the electrical utility applications include: (1) distribution structures, (2) transmission structures such as single-pole, phase over phase switch structures, tangent structures, and H-Frame construction. The applications for the telecommunication industry consist of joint use structures, such as electric and telecommunication, lighting and telecommunication, overhead telephone and wireless; mono-pole applications; three-pole Bell Towers; and tree poles. Examples of each type were shown. figs.

  12. A new method of determining moisture gradient in wood

    Science.gov (United States)

    Zhiyong Cai

    2008-01-01

    Moisture gradient in wood and wood composites is one of most important factors that affects both physical stability and mechanical performance. This paper describes a method for measuring moisture gradient in lumber and engineering wood composites as it varies across material thickness. This innovative method employs a collimated radiation beam (x rays or [gamma] rays...

  13. Fatigue behavior of wood-fiber-based tri-axial engineered sandwich composite panels (ESCP)

    Science.gov (United States)

    Jinghao Li; John F. Hunt; Shaoqin Gong; Zhiyong Cai

    2015-01-01

    The static and fatigue bending behavior of wood-fiber-based tri-axial engineered sandwich composite panels (ESCP) has been investigated by four-point bending tests. Fatigue panels and weakened panels (wESCP) with an initial interface defect were manufactured for the fatigue tests. Stress σ vs. number of cycles curves (S-N) were recorded under the different stress...

  14. Photostability and moisture uptake properties of wood veneers coated with a combination of thin sol-gel films and light stabilizers

    Science.gov (United States)

    Mandla A. Tshabalala; Ryan Libert; Christian M. Schaller

    2011-01-01

    In recent years, there has been increased interest in the use of inorganic UV blocking nanoparticles for photostabilization of wood surfaces. Photostability and moisture uptake properties of wood veneers coated with a combination of hybrid inorganic-organic thin sol-gel films and organic light stabilizers was investigated. The light stabilizers were applied by brushing...

  15. Simulation of fuel demand for wood-gas in combustion engine

    Science.gov (United States)

    Botwinska, Katarzyna; Mruk, Remigiusz; Tucki, Karol; Wata, Mateusz

    2017-10-01

    In the era of the oil crisis and proceeding contamination of the natural environment, it is attempted to substitute fossil raw materials with alternative carriers. For many years, road transport has been considered as one of the main sources of the substances deteriorating air quality. Applicable European directives oblige the member states to implement biofuels and biocomponents into the general fuel market, however, such process is proceeding gradually and relatively slowly. So far, alternative fuels have been used on a large scale to substitute diesel fuel or petrol. Derivatives of vegetable raw materials, such as vegetable oils or their esters and ethanol extracted from biomass, are used to that end. It has been noticed that there is no alternative to LPG which, due to financial reasons, is more and more popular as fuel in passenger cars. In relation to solutions adopted in the past, it has been decided to analyse the option of powering a modern passenger car with wood gas - syngas. Such fuel has been practically used since the 1920's. To that end, a computer simulation created in SciLab environment was carried out. Passenger car Fiat Seicento, fitted with Fire 1.1 8V petrol engine with power of 40kW, whose parameters were used to prepare the model, was selected as the model vehicle. The simulation allows the determination of engine demand on the given fuel. Apart from the wood gas included in the title, petrol, methane and LPG were used. Additionally, the created model enables the determination of the engine power at the time of the indicated fuels supply. The results obtained in the simulation revealed considerable decrease in the engine power when the wood gas was supplied and the increased consumption of this fuel. On the basis of the analysis of the professional literature describing numerous inconveniences connected with the use of this fuel as well as the obtained results, it has been established that using the wood gas as alternative fuel is currently

  16. Multiple myeloma and engine exhausts, fresh wood, and creosote: a case-referent study

    International Nuclear Information System (INIS)

    Flodin, U.; Fredriksson, M.; Persson, B.

    1987-01-01

    The effect of potential risk factors for multiple myeloma was evaluated in a case-referent study encompassing 131 cases and 431 randomized referents, all alive. Information on exposure was obtained with questionnaires mailed to the subjects. An analysis of the material by means of the Miettinen confounder score technique resulted in a few rate ratios significantly exceeding unity--namely, occupational exposure to engine exhausts, creosote, and fresh wood. In view of other studies that suggest ionizing radiation as a risk factor, it was somewhat surprising that low-level gamma radiation from background exposure was less common among the cases than the referents

  17. Stability of quantitative trait loci for growth and wood properties across multiple pedigrees and environments in Eucalyptus globulus.

    Science.gov (United States)

    Freeman, Jules S; Potts, Brad M; Downes, Geoffrey M; Pilbeam, David; Thavamanikumar, Saravanan; Vaillancourt, René E

    2013-06-01

    · Eucalypts are one of the most planted tree genera worldwide, and there is increasing interest in marker-assisted selection for tree improvement. Implementation of marker-assisted selection requires a knowledge of the stability of quantitative trait loci (QTLs). This study aims to investigate the stability of QTLs for wood properties and growth across contrasting sites and multiple pedigrees of Eucalyptus globulus. · Saturated linkage maps were constructed using 663 genotypes from four separate families, grown at three widely separated sites, and were employed to construct a consensus map. This map was used for QTL analysis of growth, wood density and wood chemical traits, including pulp yield. · Ninety-eight QTLs were identified across families and sites: 87 for wood properties and 11 for growth. These QTLs mapped to 38 discrete regions, some of which co-located with candidate genes. Although 16% of QTLs were verified across different families, 24% of wood property QTLs and 38% of growth QTLs exhibited significant genotype-by-environment interaction. · This study provides the most detailed assessment of the effect of environment and pedigree on QTL detection in the genus. Despite markedly different environments and pedigrees, many QTLs were stable, providing promising targets for the application of marker-assisted selection. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

  18. Engineering stabilizer measurements in circuit QED: I

    Science.gov (United States)

    Chou, Kevin; Blumoff, Jacob; Reagor, M.; Axline, C.; Brierley, R.; Nigg, S.; Reinhold, P.; Heeres, R.; Wang, C.; Sliwa, K.; Narla, A.; Hatridge, M.; Jiang, L.; Devoret, M. H.; Girvin, S. M.; Schoekopf, R. J.

    Quantum error correction based on stabilizer codes has emerged as an attractive approach towards building a practical quantum information processor. One requirement for such a device is the ability to perform hardware efficient measurements on registers of qubits. We demonstrate a new protocol to realize such multi-qubit measurements. A key feature of our approach is that it enables arbitrary stabilizer measurements to be selected in software, and requires a relatively small number of buses, ancillae, and control lines. This allows for a minimally complex sample realizing a simple dispersive hamiltonian while maintaining a high degree of decoupling between our fixed-tuned qubits. We experimentally implement these measurements in 3D circuit QED using transmon qubits coupled to a common bus resonator. In this first of two talks, we introduce our 3D cQED system and describe the protocol for measuring n-qubit parities of a three qubit register. We acknowledge funding from ARO.

  19. Engineering stabilizer measurements in circuit QED: II

    Science.gov (United States)

    Blumoff, Jacob; Chou, Kevin; Reagor, M.; Axline, C.; Brierly, R.; Nigg, S.; Reinhold, P.; Heeres, R.; Wang, C.; Sliwa, K.; Narla, A.; Hatridge, M.; Jiang, L.; Devoret, M. H.; Girvin, S. M.; Schoelkopf, R. J.

    Quantum error correction based on stabilizer codes has emerged as an attractive approach towards building a practical quantum information processor. One requirement for such a device is the ability to perform hardware efficient measurements on registers of qubits. We demonstrate a new protocol to realize such multi-qubit measurements. A key feature of our approach is that it enables arbitrary stabilizer measurements to be selected in software, and requires a relatively small number of buses, ancillae, and control lines. This allows for a minimally complex sample realizing a simple dispersive hamiltonian while maintaining a high degree of decoupling between our fixed-tuned qubits. We experimentally implement these measurements in 3D circuit QED using transmon qubits coupled to a common bus resonator. In the second of two talks, we present a full characterization of the algorithm describing the outcome dependent projections via quantum process tomography. We acknowledge funding from ARO.

  20. Acid-base synergistic flame retardant wood pulp paper with high thermal stability.

    Science.gov (United States)

    Wang, Ning; Liu, Yuansen; Xu, Changan; Liu, Yuan; Wang, Qi

    2017-12-15

    Acid-catalytic degradation caused by acid source flame retardants is the main reason for a decline in thermal stability of flame-retarded lignocellulosic materials. In the present research, a guanidine phosphate (GP)/borax (BX) flame retardant system based on acid-base synergistic interaction was designed and used in wood pulp paper (WPP) to solve this problem. Results showed that the treated WPP obtained good flame retardancy with a limiting oxygen index (LOI) value of 35.7%. As a basic flame retardant, borax could chemically combine with the acids released by guanidine phosphate, thus decreasing the acidity of the system in the initial heating stage. In this way, acid-catalytic degradation is greatly retarded on the lignocelluloses to improve thermal stability (the temperature of maximum degradation peak from 286°C to 314°C). Meanwhile, borax was also advantageous to form a denser and firmer condensed phase through reinforcement of the acid-base reaction product, borophosphates, allowing it to provide a protective barrier with higher quality. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. The electric power engineering handbook power system stability and control

    CERN Document Server

    Grisby, Leonard L

    2012-01-01

    With contributions from worldwide leaders in the field, Power System Stability and Control, Third Edition (part of the five-volume set, The Electric Power Engineering Handbook) updates coverage of recent developments and rapid technological growth in essential aspects of power systems. Edited by L.L. Grigsby, a respected and accomplished authority in power engineering, and section editors Miroslav Begovic, Prabha Kundur, and Bruce Wollenberg, this reference presents substantially new and revised content. Topics covered include: * Power System Protection * Power System Dynamics and Stability *

  2. Protein engineering of subtilisins to improve stability in detergent formulations.

    Science.gov (United States)

    von der Osten, C; Branner, S; Hastrup, S; Hedegaard, L; Rasmussen, M D; Bisgård-Frantzen, H; Carlsen, S; Mikkelsen, J M

    1993-03-01

    Microbial proteases are used extensively in a large number of industrial processes and most importantly in detergent formulations facilitating the removal of proteinaceous stains. Site-directed mutagenesis has been employed in the construction of subtilisin variants with improved storage and oxidation stabilities. It is shown that in spite of significant structural homology between subtilisins subjected to protein engineering the effects of specific mutations can be quite different. Mutations that stabilize one subtilisin may destabilize another.

  3. Engineering Lipases: walking the fine line between activity and stability

    Science.gov (United States)

    Dasetty, Siva; Blenner, Mark A.; Sarupria, Sapna

    2017-11-01

    Lipases are enzymes that hydrolyze lipids and have several industrial applications. There is a tremendous effort in engineering the activity, specificity and stability of lipases to render them functional in a variety of environmental conditions. In this review, we discuss the recent experimental and simulation studies focused on engineering lipases. Experimentally, mutagenesis studies have demonstrated that the activity, stability, and specificity of lipases can be modulated by mutations. It has been particularly challenging however, to elucidate the underlying mechanisms through which these mutations affect the lipase properties. We summarize results from experiments and molecular simulations highlighting the emerging picture to this end. We end the review with suggestions for future research which underscores the delicate balance of various facets in the lipase that affect their activity and stability necessitating the consideration of the enzyme as a network of interactions.

  4. Engineering Behavior and Characteristics of Wood Ash and Sugarcane Bagasse Ash

    Directory of Open Access Journals (Sweden)

    Francisco Grau

    2015-10-01

    Full Text Available Biomasses are organic materials that are derived from any living or recently-living structure. Plenty of biomasses are produced nationwide. Biomasses are mostly combusted and usually discarded or disposed of without treatment as biomass ashes, which include wood and sugarcane bagasse ashes. Thus, recycling or treatment of biomass ashes leads to utilizing the natural materials as an economical and environmental alternative. This study is intended to provide an environmental solution for uncontrolled disposal of biomass ashes by way of recycling the biomass ash and replacing the soils in geotechnical engineering projects. Therefore, in this study, characteristic tests of wood and sugarcane bagasse ashes that are considered the most common biomass ashes are conducted. The test of chemical compositions of biomass ashes is conducted using energy dispersive X-ray spectroscopy (EDS, and Scanning Electron Microscope (SEM, and heavy metal analysis is also conducted. Engineering behaviors including hydraulic conductivity, constrained modulus and shear modulus are examined. Also, coal fly ash Class C is used in this study for comparison with biomass ashes, and Ottawa 20/30 sands containing biomass ashes are examined to identify the soil replacement effect of biomass ashes. The results show that the particle sizes of biomass ashes are halfway between coal fly ash Class C and Ottawa 20/30 sand, and biomass ashes consist of a heterogeneous mixture of different particle sizes and shapes. Also, all heavy metal concentrations were found to be below the US Environmental Protection Agency (EPA maximum limit. Hydraulic conductivity values of Ottawa 20/30 sand decrease significantly when replacing them with only 1%–2% of biomass ashes. While both the constrained modulus and shear modulus of biomass ashes are lower than Ottawa 20/30 sand, those of mixtures containing up to 10% biomass ashes are little affected by replacing the soils with biomass ashes.

  5. Composites from southern pine juvenile wood. Part 2. Durability and dimensional stability

    Science.gov (United States)

    Anton D. Pugel; Eddie W. Price; Chung-Yun Hse

    1990-01-01

    Southern pine juvenile and mature wood were processed into three composites: flakeboard, particleboard, and fiberboard. The durability of these composites was assessed by subjecting specimens to an ovendry-vacuumpressure-soak (ODVPS) treatment, and then evaluated for modulus of elasticity, modulus of rupture, and internal bond. Overall, juvenile wood composites had...

  6. Engineering Properties of Bentonite Stabilized with Lime and Phosphogypsum

    OpenAIRE

    Kumar Sujeet; Dutta Rakesh Kumar; Mohanty Bijayananda

    2014-01-01

    Engineering properties such as compaction, unconfined compressive strength, consistency limits, percentage swell, free swell index, the California bearing ratio and the consolidation of bentonite stabilized with lime and phosphogypsum are presented in this paper. The content of the lime and phosphogypsum varied from 0 to 10 %. The results reveal that the dry unit weight and optimum moisture content of bentonite + 8 % lime increased with the addition of 8 % phosphogypsum. The percentage of swe...

  7. Signal Processing Methods for Liquid Rocket Engine Combustion Stability Assessments

    Science.gov (United States)

    Kenny, R. Jeremy; Lee, Erik; Hulka, James R.; Casiano, Matthew

    2011-01-01

    The J2X Gas Generator engine design specifications include dynamic, spontaneous, and broadband combustion stability requirements. These requirements are verified empirically based high frequency chamber pressure measurements and analyses. Dynamic stability is determined with the dynamic pressure response due to an artificial perturbation of the combustion chamber pressure (bomb testing), and spontaneous and broadband stability are determined from the dynamic pressure responses during steady operation starting at specified power levels. J2X Workhorse Gas Generator testing included bomb tests with multiple hardware configurations and operating conditions, including a configuration used explicitly for engine verification test series. This work covers signal processing techniques developed at Marshall Space Flight Center (MSFC) to help assess engine design stability requirements. Dynamic stability assessments were performed following both the CPIA 655 guidelines and a MSFC in-house developed statistical-based approach. The statistical approach was developed to better verify when the dynamic pressure amplitudes corresponding to a particular frequency returned back to pre-bomb characteristics. This was accomplished by first determining the statistical characteristics of the pre-bomb dynamic levels. The pre-bomb statistical characterization provided 95% coverage bounds; these bounds were used as a quantitative measure to determine when the post-bomb signal returned to pre-bomb conditions. The time for post-bomb levels to acceptably return to pre-bomb levels was compared to the dominant frequency-dependent time recommended by CPIA 655. Results for multiple test configurations, including stable and unstable configurations, were reviewed. Spontaneous stability was assessed using two processes: 1) characterization of the ratio of the peak response amplitudes to the excited chamber acoustic mode amplitudes and 2) characterization of the variability of the peak response

  8. New Insights on Wood Dimensional Stability Influenced by Secondary Metabolites: The Case of a Fast-Growing Tropical Species Bagassa guianensis Aubl.

    Directory of Open Access Journals (Sweden)

    Julie Bossu

    Full Text Available Challenging evaluation of tropical forest biodiversity requires the reporting of taxonomic diversity but also the systematic characterization of wood properties in order to discover new promising species for timber industry. Among wood properties, the dimensional stability is regarded as a major technological characteristic to validate whether a wood species is adapted to commercial uses. Cell structure and organization are known to influence the drying shrinkage making wood density and microfibrils angle markers of choice to predict wood dimensional stability. On the contrary the role of wood extractive content remains unclear. This work focuses on the fast-growing tropical species Bagassa guianensis and we report herein a correlation between heartwood drying shrinkage and extractive content. Chemical extractions and shrinkage experiments were performed on separate wood twin samples to better evaluate correctly how secondary metabolites influence the wood shrinkage behaviour. Extractive content were qualitatively and quantitatively analysed using HPLC and NMR spectroscopy. We found that B guianensis heartwood has a homogeneous low shrinkage along its radius that could not be explained only by its basic density. In fact the low drying shrinkage is correlated to the high extractive content and a corrected model to improve the prediction of wood dimensional stability is presented. Additionally NMR experiments conducted on sapwood and heartwood extracts demonstrate that secondary metabolites biosynthesis occurs in sapwood thus revealing B. guianensis as a Juglans-Type heartwood formation. This work demonstrates that B. guianensis, a fast-growing species associated with high durability and high dimensional stability, is a good candidate for lumber production and commercial purposes.

  9. Dimensional Stability of Poplar Wood by Paraffin Emulsion, Quaternary Ammonium and Hydrated Starch using Full-cell Treatment

    Directory of Open Access Journals (Sweden)

    Iraj Mansouryar

    2011-01-01

    In this study, the dimensional stabilization of poplar wood (Populus Alba by applying emulsion of paraffin, quaternary ammonium and starch was investigated. Paraffin at three levels of 0%, 3%, 5%, quaternary ammonium at three levels of 0%, 1.5%, 2.5% and starch at three levels of 0%, 1% and 2% were selected as variables. Some physical characteristics including longitudinal, tangential and radial swelling were determined. Based on the results, for optimizing physical properties, the treatment of 5% paraffin, 0-1.5% quaternary ammonium and 0-1% starch was recommended.

  10. Methylation of Brazilein on Secang (Caesalpinia sappan Linn) Wood Extract for Maintain Color Stability to the Changes of pH

    Science.gov (United States)

    Ulma, Zeni; Rahayuningsih, Edia; Dwi Wahyuningsih, Tutik

    2018-01-01

    The stability of natural dyes to the changes of pH is really necessary when the natural dyes are applied either on fabric or food. This research aimed to increase the stability of brazilein, a compound contained within the secang wood extract, to the changes of pH. The methylation process was done by reacting Dimethyl Carbonate (DMC) with the brazilein on the secang wood extract. DMC acts as a substance that substitute hydroxyl group on brazilein. The methylation reaction of brazilein on secang wood extract was operated on a three-necked round-bottomed flask fitted with mercury-sealed stirrer and reflux condenser under 80°C temperature and 250 rpm stirring speed. There were two variables observed in this research; the DMC amount ratio to the amount of secang wood extract and the time of the methylation process. The research showed that at the 1:10 the DMC amount ratio to the amount of wood extract and 8 hours of the methylation process give the better stability of color of the secang wood extract than the variation of the other variables.

  11. Coupling effect of waste automotive engine oil in the preparation of wood reinforced LDPE plastic composites for panels

    Directory of Open Access Journals (Sweden)

    Maame Adwoa Bentumah Animpong

    2017-12-01

    Full Text Available We demonstrated the formulation of wood plastic composite (WPC materials with flexural strength of 13.69 ± 0.09 MPa for applications in outdoor fencing using municipal waste precursors like low density polyethylene (LDPE plastics (54.0 wt. %, sawn wood dust with particle size between 64 and 500 μm derived from variable hardwood species (36.0 wt. % and used automotive engine oil (10 wt. %. The WPC panels were prepared by pre-compounding, extruding at a screw auger torque of 79.8 Nm and pressing through a rectangular mould of dimension 132 mm × 37 mm × 5 mm at temperature 150 °C. The efficacy of black waste oil, as a coupling agent, was demonstrated by the absence of voids and pull-outs on microscopic examination using scanning electron microscopy. No hazardous substances were exhaled during thermo-gravimetric mass spectrometry analysis. The percentage crystallinity of the LDPE in the as-prepared material determined by differential scanning calorimetry was 11.3%. Keywords: Wood plastic composites, Low density polyethylene, Wood dust, Physical, Thermal and mechanical properties

  12. Changes in SOM composition and stability to microbial degradation over time in response to wood chip ash fertilisation

    DEFF Research Database (Denmark)

    Hansen, Mette; Saarsalmi, Anna; Peltre, Clement

    2016-01-01

    in Denmark, where ash had been spread at different times. Changes in SOM biodegradability were estimated based on an incubation experiment, expressed as percentage of initial carbon. Changes in SOM composition were characterised using thermal analysis and Fourier transform mid-infrared photoacoustic......Recirculation of nutrients from wood chip combustion by ash fertilisation of forest systems can be used to re-introduce nutrients that are otherwise lost, counteracting nutrient depletion due to whole tree harvesting. However, the effects of ash application on soil organic matter (SOM) composition......, turnover and stability are unknown. The aim of the study was to investigate how ash fertilisation of forest soils affects SOM composition and stability to microbial degradation over time. O-horizon and 0–5 cm mineral soil samples were collected from two coniferous forest sites, one in Finland and one...

  13. Dynamic mechanical properties and thermal stability of furfuryl alcohol and nano-SiO2 treated poplar wood

    Science.gov (United States)

    Dong, Youming; Shen, Xiaoyan; Zhang, Shifeng; Li, Jianzhang

    2015-07-01

    Wood polymer nanocomposites (WPNC) were prepared from the furfuryl alcohol and nano-SiO2 using a method of vacuum impregnation. Dynamic mechanical properties in storage modulus and mechanical loss factor, as well as the thermal stability of the WPNC were evaluated. The interface interaction between the organic and inorganic compounds was also studied by the scanning electron microscope and energy dispersive X-ray spectrometer. The dynamic mechanical analysis showed the improvement in the storage modulus and mechanical loss factor of WPNC as a result of the strong interfacial interaction between the organic and inorganic matrix. Additionally, with an increase in nanoparticles content in the composites, the thermo-stability of WPNC improved significantly.

  14. Status on the Verification of Combustion Stability for the J-2X Engine Thrust Chamber Assembly

    Science.gov (United States)

    Casiano, Matthew; Hinerman, Tim; Kenny, R. Jeremy; Hulka, Jim; Barnett, Greg; Dodd, Fred; Martin, Tom

    2013-01-01

    Development is underway of the J -2X engine, a liquid oxygen/liquid hydrogen rocket engine for use on the Space Launch System. The Engine E10001 began hot fire testing in June 2011 and testing will continue with subsequent engines. The J -2X engine main combustion chamber contains both acoustic cavities and baffles. These stability aids are intended to dampen the acoustics in the main combustion chamber. Verification of the engine thrust chamber stability is determined primarily by examining experimental data using a dynamic stability rating technique; however, additional requirements were included to guard against any spontaneous instability or rough combustion. Startup and shutdown chug oscillations are also characterized for this engine. This paper details the stability requirements and verification including low and high frequency dynamics, a discussion on sensor selection and sensor port dynamics, and the process developed to assess combustion stability. A status on the stability results is also provided and discussed.

  15. Epoxy adhesive formulations for engineered wood manufacturing: Design of Experiment (DOE) and hardener modification

    Science.gov (United States)

    Wangkheeree, W.; Meekum, U.

    2016-03-01

    The effect of IPDA, DDS, BPA and DICY, as main ingredient of TETA based hardener were examined. The 2k design of experiment(DOE) with k=3 were preliminary explored. The designed parameters A(IPDA), B(DDS) and C(BPA) were assigned as low(-) and high(+) levels, respectively. The Design Expert™ was hired as the analyzing tool at α=0.05. The mixed epoxy resin was based on the commercial one. The designed responds including tcure, t50, impact strengths, flexural properties and HDT were measured, respectively. Regarding to ANOVA conclusion, it was found that, there were no significant effects on the assigned parameters on the interested responds, except for the HDT where BPA(C) was negative effect was found. The lower in the crosslink density of cured epoxy, inferior in HDT, the higher in BPA addition was hypothesized. It was found that impact strength of cured epoxy derived from all formula were unacceptable low and tcure and t50, were too short. Thus, the further investigation by adding DICY into hardener was explored. The results showed that no significant change by mechanical means of cured epoxy by resolving 5-30 phr of DICY into the hardener. However, it was observed that the DICY added formula showed the obvious long cure times and behave as prepreg formula. The room temperature cured epoxy was incompletely crosslinked. The degrees of linear chain fragment were evidence, by weight, when higher DICY loading was engaged. Complete crosslink was achieved at 150°C post curing. The hardener comprised of TETA/aliphatic Epoxy(RD108) adduct was studied for enhancing the toughness of epoxy resin. It was observed that longer cure time at 150°C but lower toughness was experienced, on both prepreg and engineered wood made from the resins, at high TETA/RD108 ratio. Incomplete cure was explained for the mechanical inferior at high RD108 loading.

  16. Signal Processing Methods for Liquid Rocket Engine Combustion Spontaneous Stability and Rough Combustion Assessments

    Science.gov (United States)

    Kenny, R. Jeremy; Casiano, Matthew; Fischbach, Sean; Hulka, James R.

    2012-01-01

    Liquid rocket engine combustion stability assessments are traditionally broken into three categories: dynamic stability, spontaneous stability, and rough combustion. This work focuses on comparing the spontaneous stability and rough combustion assessments for several liquid engine programs. The techniques used are those developed at Marshall Space Flight Center (MSFC) for the J-2X Workhorse Gas Generator program. Stability assessment data from the Integrated Powerhead Demonstrator (IPD), FASTRAC, and Common Extensible Cryogenic Engine (CECE) programs are compared against previously processed J-2X Gas Generator data. Prior metrics for spontaneous stability assessments are updated based on the compilation of all data sets.

  17. Improving the color stability of wood-plastic composites through fiber pre-treatment

    Science.gov (United States)

    Nicole M. Stark; Scott A. Mueller

    2008-01-01

    Wood-plastic composites (WPCs) continue to make inroads into the decking market. One of the main drawbacks from the consumer’s perspective is that they can fade during weathering. It has been shown that WPCs fade more when exposed to a combination of light and water spray than when exposed only to light. This suggests that the loss of the color-imparting extractives...

  18. An engineering economic assessment of whole-house residential wood heating in New York

    Science.gov (United States)

    Wood devices are being selected increasingly for residential space heating by households in New York State. Motivations for their use include energy independence, mitigating climate change, stimulating local economic development, and reducing exposure to high and variable fuel c...

  19. Plutonium Finishing Plant. Interim plutonium stabilization engineering study

    Energy Technology Data Exchange (ETDEWEB)

    Sevigny, G.J.; Gallucci, R.H.; Garrett, S.M.K.; Geeting, J.G.H.; Goheen, R.S.; Molton, P.M.; Templeton, K.J.; Villegas, A.J. [Pacific Northwest Lab., Richland, WA (United States); Nass, R. [Nuclear Fuel Services, Inc. (United States)

    1995-08-01

    This report provides the results of an engineering study that evaluated the available technologies for stabilizing the plutonium stored at the Plutonium Finishing Plant located at the hanford Site in southeastern Washington. Further processing of the plutonium may be required to prepare the plutonium for interim (<50 years) storage. Specifically this document provides the current plutonium inventory and characterization, the initial screening process, and the process descriptions and flowsheets of the technologies that passed the initial screening. The conclusions and recommendations also are provided. The information contained in this report will be used to assist in the preparation of the environmental impact statement and to help decision makers determine which is the preferred technology to process the plutonium for interim storage.

  20. Plutonium Finishing Plant. Interim plutonium stabilization engineering study

    International Nuclear Information System (INIS)

    Sevigny, G.J.; Gallucci, R.H.; Garrett, S.M.K.; Geeting, J.G.H.; Goheen, R.S.; Molton, P.M.; Templeton, K.J.; Villegas, A.J.; Nass, R.

    1995-08-01

    This report provides the results of an engineering study that evaluated the available technologies for stabilizing the plutonium stored at the Plutonium Finishing Plant located at the hanford Site in southeastern Washington. Further processing of the plutonium may be required to prepare the plutonium for interim (<50 years) storage. Specifically this document provides the current plutonium inventory and characterization, the initial screening process, and the process descriptions and flowsheets of the technologies that passed the initial screening. The conclusions and recommendations also are provided. The information contained in this report will be used to assist in the preparation of the environmental impact statement and to help decision makers determine which is the preferred technology to process the plutonium for interim storage

  1. BWR stability analysis with the BNL Engineering Plant Analyzer

    International Nuclear Information System (INIS)

    Wulff, W.; Cheng, H.S.; Mallen, A.N.; Rohatgi, U.S.

    1992-10-01

    March 9, 1989 instability at the LaSalle-2 Power Plant and more than ninety related BWR transients have been simulated on the BNL Engineering Plant Analyzer (EPA). Power peaks were found to be potentially seventeen times greater than the rated power, flow reversal occurs momentarily during large power oscillations, the fuel centerline temperature oscillates between 1,030 and 2,090 K, while the cladding temperature oscillates between 560 and 570 K. The Suppression Pool reaches its specified temperature limit either never or in as little as 4.3 minutes, depending on operator actions and transient scenario. Thermohydraulic oscillations occur at low core coolant flow (both Recirculation Pumps tripped), with sharp axial or redial fission power peaking and with partial loss of feedwater preheating while the feedwater is flow kept high to maintain coolant inventory in the vessel. Effects from BOP system were shown to influence reactor stability strongly through dosed-loop resonance feedback. High feedwater flow and low temperature destabilize the reactor. Low feedwater flow restabilizes the reactor, because of steam condensation and feedwater preheating in the downcomer, which reduces effectively the destabilizing core inlet subcooling. The EPA has been found to be capable of analyzing BWR stability '' shown to be effective for scoping calculations and for supporting accident management

  2. Engineering Properties of Bentonite Stabilized with Lime and Phosphogypsum

    Science.gov (United States)

    Kumar, Sujeet; Dutta, Rakesh Kumar; Mohanty, Bijayananda

    2014-12-01

    Engineering properties such as compaction, unconfined compressive strength, consistency limits, percentage swell, free swell index, the California bearing ratio and the consolidation of bentonite stabilized with lime and phosphogypsum are presented in this paper. The content of the lime and phosphogypsum varied from 0 to 10 %. The results reveal that the dry unit weight and optimum moisture content of bentonite + 8 % lime increased with the addition of 8 % phosphogypsum. The percentage of swell increased and the free swell index decreased with the addition of 8 % phosphogypsum to the bentonite + 8 % lime mix. The unconfined compressive strength of the bentonite + 8 % lime increased with the addition of 8 % phosphogypsum as well as an increase in the curing period up to 14 days. The liquid limit and plastic limit of the bentonite + 8 % lime increased, whereas the plasticity index remained constant with the addition of 8 % phosphogypsum. The California bearing ratio, modulus of subgrade reaction, and secant modulus increased for the bentonite stabilized with lime and phosphogypsum. The coefficient of the consolidation of the bentonite increased with the addition of 8 % lime and no change with the addition of 8 % phosphogypsum.

  3. Engineering Properties of Bentonite Stabilized with Lime and Phosphogypsum

    Directory of Open Access Journals (Sweden)

    Kumar Sujeet

    2014-12-01

    Full Text Available Engineering properties such as compaction, unconfined compressive strength, consistency limits, percentage swell, free swell index, the California bearing ratio and the consolidation of bentonite stabilized with lime and phosphogypsum are presented in this paper. The content of the lime and phosphogypsum varied from 0 to 10 %. The results reveal that the dry unit weight and optimum moisture content of bentonite + 8 % lime increased with the addition of 8 % phosphogypsum. The percentage of swell increased and the free swell index decreased with the addition of 8 % phosphogypsum to the bentonite + 8 % lime mix. The unconfined compressive strength of the bentonite + 8 % lime increased with the addition of 8 % phosphogypsum as well as an increase in the curing period up to 14 days. The liquid limit and plastic limit of the bentonite + 8 % lime increased, whereas the plasticity index remained constant with the addition of 8 % phosphogypsum. The California bearing ratio, modulus of subgrade reaction, and secant modulus increased for the bentonite stabilized with lime and phosphogypsum. The coefficient of the consolidation of the bentonite increased with the addition of 8 % lime and no change with the addition of 8 % phosphogypsum.

  4. Grain boundary engineering to enhance thermal stability of electrodeposited nickel

    DEFF Research Database (Denmark)

    Alimadadi, Hossein

    Manufacturing technologies such as injection molding and micro electromechanical systems demand materials with improved mechanical properties (e.g. hardness, ductility) and high durability at elevated temperatures. Significant improvement in some of the mechanical properties is obtained by miniat......Manufacturing technologies such as injection molding and micro electromechanical systems demand materials with improved mechanical properties (e.g. hardness, ductility) and high durability at elevated temperatures. Significant improvement in some of the mechanical properties is obtained...... by miniaturization of the grains down to nano-meter scale. However, this augments the total grain boundary energy stored in the material, hence, making the material less thermally stable. Coherent twin boundaries are of very low energy and mobility compared to all other boundaries in a FCC material. Accordingly......, grain boundary engineering of electrodeposited nickel to achieve high population of coherent twin boundaries and, hence, higher thermal stability is a promising method to achieve simultaneous improvement in mechanical properties and thermal stability. This is of particular scientific and practical...

  5. Transport of stabilized engineered silver (Ag) nanoparticles through porous sandstones

    Science.gov (United States)

    Neukum, Christoph; Braun, Anika; Azzam, Rafig

    2014-03-01

    Engineered nanoparticles are increasingly applied in consumer products and concerns are rising regarding their risk as potential contaminants or carriers for colloid-facilitated contaminant transport. Engineered silver nanoparticles (AgNP) are among the most widely used nanomaterials in consumer products. However, their mobility in groundwater has been scarcely investigated. In this study, transport of stabilized AgNP through porous sandstones with variations in mineralogy, pore size distribution and permeability is investigated in laboratory experiments with well-defined boundary conditions. The AgNP samples were mainly characterized by asymmetric flow field-flow fractionation coupled to a multi-angle static laser light detector and ultraviolet-visible spectroscopy for determination of particle size and concentration. The rock samples are characterized by mercury porosimetry, flow experiments and solute tracer tests. Solute and AgNP breakthrough was quantified by applying numerical models considering one kinetic site model for particle transport. The transport of AgNP strongly depends on pore size distribution, mineralogy and the solution ionic strength. Blocking of attachment sites results in less reactive transport with increasing application of AgNP mass. AgNPs were retained due to physicochemical filtration and probably due to straining. The results demonstrate the restricted applicability of AgNP transport parameters determined from simplified experimental model systems to realistic environmental matrices.

  6. The Gas turbine Engine-based Power Technology Plant Using Wood Waste Gasification Products

    OpenAIRE

    S. K. Danilova; R. Z. Tumashev

    2016-01-01

    The paper outlines the problems of energy supply and waste utilization of the forest industries. As a solution, it proposes to use gasification to utilize wood leftovers, which is followed by electric power generation from combustion of producer gas. The plant was expected to have a power of 150 kW. The proposed power technology plant comprises a line for pre-treatment of wood chips, a gas generator (gasifier) and a gas turbine unit.The paper justifies a need for preliminary preparation of wo...

  7. Changes in SOM composition and stability to microbial degradation over time in response to wood chip ash fertilisation

    Science.gov (United States)

    Hansen, Mette; Saarsalmi, Anna; Peltre, Clément

    2017-04-01

    Recirculation of nutrients from wood chip combustion by ash fertilisation of forest systems can be used to re-introduce nutrients that are otherwise lost, counteracting nutrient depletion due to whole tree harvesting. However, the effects of ash application on soil organic matter (SOM) composition, turnover and stability are unknown. The aim of the study was to investigate how ash fertilisation of forest soils affects SOM composition and stability to microbial degradation over time. O-horizon and 0-5 cm mineral soil samples were collected from two coniferous forest sites, one in Finland and one in Denmark, where ash had been spread at different times. Changes in SOM biodegradability were estimated based on an incubation experiment, expressed as percentage of initial carbon. Changes in SOM composition were characterised using thermal analysis and Fourier transform mid-infrared photoacoustic spectroscopy (FTIR-PAS) analysis of bulk soil samples. Ash fertilisation of forest soils affected SOM composition in the O-horizon, but not in the top 5 cm of the mineral soil. The pH and biodegradability of SOM were increased in the O-horizon. The changes in SOM composition consisted of enrichment of Fe- and Al-oxides/ hydroxides, depletion of carboxylic and aromatic groups and lower thermal stability in soils with older and greater ash application. Ash fertilisation increased soil pH, either right after ash application or through a buffering effect of the ash on acidification caused by decomposing needles over time. The increased pH due to ash fertilisation together with the nutrient inputs from the ash most likely stimulated SOM turnover. This in turn increased the labile fraction of SOM, whereby the thermal stability of SOM decreased as simpler compounds were formed.

  8. Potassium methyl siliconate-treated pulp fibers and their effects on wood plastic composites: Water sorption and dimensional stability

    Science.gov (United States)

    Cheng Piao; Zhiyong Cai; Nicole M. Stark; Charles J. Monlezun

    2013-01-01

    Potassium methyl siliconate (PMS) was investigated as a new nano modifier of wood fiber and wood flour to improve the compatibility between the fiber/flour and the plastic matrix in fiber reinforced plastic composites. Before injection molding, bleached and brown pulp fibers and mixed species wood flour were pretreated in PMS solutions. The morphology of the treated...

  9. Flavonoid insertion into cell walls improves wood properties.

    Science.gov (United States)

    Ermeydan, Mahmut A; Cabane, Etienne; Masic, Admir; Koetz, Joachim; Burgert, Ingo

    2012-11-01

    Wood has an excellent mechanical performance, but wider utilization of this renewable resource as an engineering material is limited by unfavorable properties such as low dimensional stability upon moisture changes and a low durability. However, some wood species are known to produce a wood of higher quality by inserting mainly phenolic substances in the already formed cell walls--a process so-called heartwood formation. In the present study, we used the heartwood formation in black locust (Robinia pseudoacacia) as a source of bioinspiration and transferred principles of the modification in order to improve spruce wood properties (Picea abies) by a chemical treatment with commercially available flavonoids. We were able to effectively insert hydrophobic flavonoids in the cell wall after a tosylation treatment for activation. The chemical treatment reduced the water uptake of the wood cell walls and increased the dimensional stability of the bulk spruce wood. Further analysis of the chemical interaction of the flavonoid with the structural cell wall components revealed the basic principle of this bioinspired modification. Contrary to established modification treatments, which mainly address the hydroxyl groups of the carbohydrates with hydrophilic substances, the hydrophobic flavonoids are effective by a physical bulking in the cell wall most probably stabilized by π-π interactions. A biomimetic transfer of the underlying principle may lead to alternative cell wall modification procedures and improve the performance of wood as an engineering material.

  10. The Gas turbine Engine-based Power Technology Plant Using Wood Waste Gasification Products

    Directory of Open Access Journals (Sweden)

    S. K. Danilova

    2016-01-01

    Full Text Available The paper outlines the problems of energy supply and waste utilization of the forest industries. As a solution, it proposes to use gasification to utilize wood leftovers, which is followed by electric power generation from combustion of producer gas. The plant was expected to have a power of 150 kW. The proposed power technology plant comprises a line for pre-treatment of wood chips, a gas generator (gasifier and a gas turbine unit.The paper justifies a need for preliminary preparation of wood waste, particularly chipping and drying. Various drying schemes have been analyzed. A line for pre-treatment of wood chips comprises a drum chipper, a receiving raw material wood container and a drum dryer using fume gases.A co-current gasifier is chosen because of the high content of tar in the original fuel. In the co-current gasifier, most of the tar, passing through the high temperature area, is burned. The paper offers high temperature dry cleaning of producer gas in the cyclone separator. Such a scheme of cleaning provides high efficiency of the plant and simplifies its design, but suspended particles still remain in the producer gas. When analyzing the schemes of power converters this is taken into account.A choice of the gas turbine as a power converter is justified. To reduce the erosion damage of the turbine blades there is a proposal to use an unconventional gas turbine scheme with air turbine and a combustion chamber located downstream of the turbine. In this plant the air rather than the combustion gas passes through the turbine. The air from turbine goes into the combustion chamber, the combustion gas passes through the air heater, where it transfers heat to the air. Such scheme allows reducing power costs for the fuel gas compression before the combustion chamber.Optimization of the gas turbine cycle is performed. The optimum compressor pressure ratio is 3,7. The plant efficiency for this pressure ratio is 25,7%. Calculation results of the

  11. Bio-engineering for land stabilization : executive summary report.

    Science.gov (United States)

    2010-06-30

    Soil-bioengineering, or simply : bioengineering, is the use of vegetation for : slope stabilization. Currently, a large : number of slopes near Ohio highways are : experiencing stability problems. These : failures usually begin as local erosion...

  12. Effectiveness of Polyacrylamide, Wood Shred Mulch, and Pine Needle Mulch as Post-Fire Hillslope Stabilization Treatments in Two Contrasting Volcanic Soils

    Directory of Open Access Journals (Sweden)

    Jonay Neris

    2017-07-01

    Full Text Available Post-fire hillslope stabilization treatments aim to reduce runoff-erosion risks following forest fires by counteracting the impact of fire on key soil and hillslope properties. Here we evaluate the effectiveness of wood shred mulch, long-leaved pine needle mulch, and polyacrylamide (PAM in reducing post-fire runoff and erosion in two volcanic soil types of contrasting wettability using rainfall simulations (55 mm h−1 for 30 min at the microplot (0.25 m2 scale. The cover provided by the wood shreds and pine needles led to a reduction of runoff and erosion in both the wettable—(62% and 92%, respectively, for wood shreds, and 55% and 87%, respectively, for needle mulch and the extremely water-repellent soils (44% and 61%, respectively, for wood shreds. In contrast to what might be expected, PAM did not reduce runoff or erosion when applied to the extremely water-repellent soils, suggesting that PAM should not be applied in this terrain type. Although more research is needed to determine whether the high effectiveness of pine needle mulch and wood shred mulch fully translates to coarser scales, the results are encouraging in terms of these materials’ ability to provide effective and relatively economic mitigation treatments for fire-induced runoff-erosion risks in volcanic soils.

  13. Results from tests of a Stirling engine and wood chips gasifier plant

    DEFF Research Database (Denmark)

    Carlsen, Henrik; Bovin, Jonas Kabell; Werling, J.

    2002-01-01

    The combination of thermal gasification and a Stirling engine is an interesting concept for use in small Combined Heat and Power (CHP) plants based on biomass, because the need for gas cleaning is eliminated and problems with fouling of the Stirling engine heater are considerably reduced...... gas and for utilisation of preheated air. A mathematical simulation model has been developed as a tool for the analyses of the Stirling engine gasifier system. The paper presents results from a simulation of the Stirling engine demonstration plant in a typical operating condition, and the result...... of the Stirling engine reduces the problems with tar to a minor problem in the design of the burner. The Stirling engine, which has an electric power output of 35 kW, is specifically designed for utilisation of fuels with a content of particles. The gas burner for the engine is designed for low specific energy...

  14. Wood products used in constructing conservation and development projects by the Corps of Engineers in the United States, 1962 and 1978

    Science.gov (United States)

    W. H. Reid; D. B. McKeever

    Estimates of the amounts of wood products used in constructing civil conservation and development projects by the Corps of Engineers in the United States are presented for the years 1962 and 1978. Amounts of lumber, laminated lumber, poles and piling, and plywood used in construction are stratified by five construction categories, and three types of uses. Estimates of...

  15. Engineering properties of stabilized subgrade soils for implementation of the AASHTO 2002 pavement design guide.

    Science.gov (United States)

    2009-06-01

    A comprehensive laboratory study was undertaken to determine engineering properties of cementitiously stabilized common subgrade soils in Oklahoma for the design of roadway pavements in accordance with the AASHTO 2002 Mechanistic-Empirical Pavement D...

  16. ENGINEERING BULLETIN: SOLIDIFICATION/STABILIZATION OF ORGANICS AND INORGANICS

    Science.gov (United States)

    Solidification refers to techniques that encapsulate hazardous waste into a solid material of high structural integrity. Encapsulation involves either fine waste particles (microencapsulation) or a large block or container of wastes (macroencapsulation). Stabilization refe...

  17. Engineering Task Plan for Hose-In-Hose Transfer Lines for the Interim Stabilization Program

    International Nuclear Information System (INIS)

    TORRES, T.D.

    2000-01-01

    The document is the Engineering Task Plan for the engineering, design services, planning, project integration and management support for the design, modification, installation and testing of an over ground transfer (OGT) system to support the interim stabilization of S/SX and U Tank Farms

  18. Bio-engineering for land stabilization : final report.

    Science.gov (United States)

    2010-06-01

    As part of the Ohio Department of Transportations (ODOTs) ongoing effort to solve engineering problems for the Ohio : transportation system through research, The Ohio State University has undertaken a study entitled Bioengineering for : Land...

  19. Robust Stabilization of Jet Engine Compressor In The Presence of ...

    African Journals Online (AJOL)

    In this work, first we modify the Moore and Grietzer three-state model for compressors to include disturbance (noise signals) and then use the method of integrator backstepping, coupled with saturation functions to develop robust controllers for the stabilization of the compressor. Also, we develop robust observers for ...

  20. Strength loss in decayed wood

    Science.gov (United States)

    Rebecca E. Ibach; Patricia K. Lebow

    2014-01-01

    Wood is a durable engineering material when used in an appropriate manner, but it is susceptible to biological decay when a log, sawn product, or final product is not stored, handled, or designed properly. Even before the biological decay of wood becomes visually apparent, the decay can cause the wood to become structurally unsound. The progression of decay to that...

  1. Space shuttle maneuvering engine reusable thrust chamber program. Task 11: Low Epsilon stability test plan

    Science.gov (United States)

    Pauckert, R. P.

    1974-01-01

    The performance and heat transfer characteristics of a doublet element type injector for the space shuttle orbiter maneuvering engine thrust chamber were investigated. Ths stability characteristics were evaluated over a range of chamber pressures and mixture ratios. The specific objectives of the test were: (1) to determine whether stability has been influenced by injection of boundary layer coolant across the cavity entrance, (2) if the injector is stable, to determine the minimum cavity area required to maintain stability, and (3) if the injector is unstable, to determine the effects of entrance geometry and increased area on stability.

  2. Does the Future Engineer Force Transition Engineer Units between Offensive and Stability Operations in Ways That Achieve Responsiveness, Versatility, Agility, Effectiveness, and Efficiency?

    National Research Council Canada - National Science Library

    London, David T

    2005-01-01

    .... The main question is as follows: Does the FEF transition engineer units between offensive and stability operations in ways that achieve responsiveness, versatility, agility, effectiveness, and efficiency...

  3. Moisture Transport in Wood

    DEFF Research Database (Denmark)

    Astrup, Thomas; Hansen, Kurt Kielsgaard; Hoffmeyer, Preben

    2005-01-01

    Modelling of moisture transport in wood is of great importance as most mechanical and physical properties of wood depend on moisture content. Moisture transport in porous materials is often described by Ficks second law, but several observations indicate that this does not apply very well to wood....... Recently at the Technical University of Denmark, Department of Civil Engineering, a new model for moisture transport in wood has been developed. The model divides the transport into two phases, namely water vapour in the cell lumens and bound water in the cell walls....

  4. Floodplains and wood

    Science.gov (United States)

    Wohl, Ellen

    2013-08-01

    Interactions between floodplains and wood date to the Carboniferous, when stable, multithread channel deposits appear with the evolution of tree-like plants. Foundational geologic texts, such as Lyell's, 1830Principles of Geology, describe floodplain-wood interactions, yet modern technical literature describes floodplain-wood interactions in detail for only a very limited range of environments. This likely reflects more than a century of deforestation, flow regulation, and channel engineering, including instream wood removal, which has resulted in severe wood depletion in most of the world's river networks. Instream wood affects floodplain form and process by altering flow resistance, conveyance and channel-floodplain connectivity, and influencing lateral and vertical accretion of floodplains. Instream wood reflects floodplain form and process as the floodplain influences wood recruitment via bank erosion and overbank flow, and wood transport and storage via floodplain effects on stage-discharge relations and flow resistance. Examining turnover times for instream wood at the reach scale in the context of a wood budget, floodplain characteristics influence fluvial transport and dynamics (wood recruitment), valley geometry (wood transport and storage), and hydraulics and river biota (wood decay and breakage). Accumulations of wood that vary from in situ jams and beaver dams in small channels to transport jams and log rafts in very large rivers can create stable, multithread channels and floodplain wetlands. Floodplain-wood interactions are best understood for a subset of small to medium-sized rivers in the temperate zone. We know little about these interactions on very large rivers, or on rivers in the tropical or boreal regions. This review suggests that most, if not all, channels and floodplains within forested catchments in the temperate zone historically had much greater wood loads and consequently much more obvious and important influences from wood than do

  5. Stochastic stability assessment of a semi-free piston engine generator concept

    Science.gov (United States)

    Kigezi, T. N.; Gonzalez Anaya, J. A.; Dunne, J. F.

    2016-09-01

    Small engines, as power generators with low-noise and vibration characteristics, are needed in two niche application areas: as electric vehicle range extenders and as domestic micro Combined Heat and Power systems. A recent semi-free piston design known as the AMOCATIC generator fully meets this requirement. The engine potentially allows for high energy conversion efficiencies at resonance derived from having a mass and spring assembly. As with free-piston engines in general, stability and control of piston motion has been cited as the prime challenge limiting the technology's widespread application. Using physical principles, we derive in this paper two important results: an energy balance criterion and a related general stability criterion for a semi-free piston engine. Control is achieved by systematically designing a Proportional Integral (PI) controller using a control-oriented engine model for which a specific stability condition is stated. All results are presented in closed form throughout the paper. Simulation results under stochastic pressure conditions show that the proposed energy balance, stability criterion, and PI controller, operate as predicted to yield stable engine operation at fixed compression ratio.

  6. Stochastic stability assessment of a semi-free piston engine generator concept

    International Nuclear Information System (INIS)

    Kigezi, T N; Anaya, J A Gonzalez; Dunne, J F

    2016-01-01

    Small engines, as power generators with low-noise and vibration characteristics, are needed in two niche application areas: as electric vehicle range extenders and as domestic micro Combined Heat and Power systems. A recent semi-free piston design known as the AMOCATIC generator fully meets this requirement. The engine potentially allows for high energy conversion efficiencies at resonance derived from having a mass and spring assembly. As with free-piston engines in general, stability and control of piston motion has been cited as the prime challenge limiting the technology's widespread application. Using physical principles, we derive in this paper two important results: an energy balance criterion and a related general stability criterion for a semi-free piston engine. Control is achieved by systematically designing a Proportional Integral (PI) controller using a control-oriented engine model for which a specific stability condition is stated. All results are presented in closed form throughout the paper. Simulation results under stochastic pressure conditions show that the proposed energy balance, stability criterion, and PI controller, operate as predicted to yield stable engine operation at fixed compression ratio. (paper)

  7. A rapid, ensemble and free energy based method for engineering protein stabilities.

    Science.gov (United States)

    Naganathan, Athi N

    2013-05-02

    Engineering the conformational stabilities of proteins through mutations has immense potential in biotechnological applications. It is, however, an inherently challenging problem given the weak noncovalent nature of the stabilizing interactions. In this regard, we present here a robust and fast strategy to engineer protein stabilities through mutations involving charged residues using a structure-based statistical mechanical model that accounts for the ensemble nature of folding. We validate the method by predicting the absolute changes in stability for 138 experimental mutations from 16 different proteins and enzymes with a correlation of 0.65 and importantly with a success rate of 81%. Multiple point mutants are predicted with a higher success rate (90%) that is validated further by comparing meosphile-thermophile protein pairs. In parallel, we devise a methodology to rapidly engineer mutations in silico which we benchmark against experimental mutations of ubiquitin (correlation of 0.95) and check for its feasibility on a larger therapeutic protein DNase I. We expect the method to be of importance as a first and rapid step to screen for protein mutants with specific stability in the biotechnology industry, in the construction of stability maps at the residue level (i.e., hot spots), and as a robust tool to probe for mutations that enhance the stability of protein-based drugs.

  8. Treatments that enhance physical properties of wood

    Science.gov (United States)

    Roger M. Rowell; Peggy Konkol

    1987-01-01

    This paper was prepared for anyone who wants to know more about enhancing wood’s physical properties, from the amateur wood carver to the president of a forest products company. The authors describe chemical and physical treatments of wood that enhance the strength, stiffness, water repellency, and stability of wood. Five types of treatments are described: 1. water-...

  9. Partially stabilized zirconia (PSZ) - what's in it for chemical engineers?

    International Nuclear Information System (INIS)

    Michelmore, A.G.

    1988-01-01

    Partial Stabilized Zirconia (PSZ) is a non-brittle ceramic material with virtually the same modulus of elasticity, Poisson's ratio, tensile strength, and co-efficient of thermal expansion as steel, coupled with low thermal conductivity, low electrical conductivity, high hardness, non-magnetic properties and high corrosion resistance. Uses are in a wide variety of applications such as automotive, computer, hot copper extrusion dies, delicate laboratory equipment, mining spigots and injection moulding gates for plastic. Applications previously thought to be impossible for ceramics such as in high thermal and/or mechanical shock situations are now possible with benefits such as longer life, reduced maintenance costs, less downtime, lower stock inventory and improved productivity. Examples given here include downhole pump check valves in the oil and gas industry, dry bearings in the mining industry and plungers for pumping tomato paste in the food processing industry. A brief comparison is made of other PSZs and Nilcra PSZ. 1 fig

  10. Transport of CO2 foam stabilized with engineered nanoparticles

    Science.gov (United States)

    Prigiobbe, V.; Worthen, A. J.; Aroonsri, A.; Huh, C.; Bryant, S. L.

    2014-12-01

    Foam injection into the subsurface is performed to improve gas control mobility for residual oil extraction in, e.g., enhanced oil recovery and contaminated site remediation. Foam improves the gas mobility control as the gas viscosity is increased through its dispersion into a liquid phase. Finer the bubbles the lower the gas apparent viscosity (or foam viscosity) and the better is the sweep efficiency of the residual oil. A chemical surfactant adsorbed at the gas-liquid interface is generally used to maintain an optimal foam texture (number of bubbles for unit volume) however it can be desorbed making the foam coarser. Here, we present an experimental and modeling study on the effect of nanoparticles on foam stability. Nanoparticles are adsorbed onto the bubble interface irreversibly and therefore they are expected to keep the desired texture of the foam for the entire time of its application. In this study, we use silica nanoparticles in conjunction with a surfactant to study the transport behavior of a CO2 foam in a porous medium. Experiments were performed using a glass-bead pack and Boise sandstone with foam quality (fg) 0.1-0.9 until steady-state. Foam flow was described by a mechanistic population balance model coupled with the fractional flow equation and constitutive equations for foam generation and destruction based on lamella division and bubble coalescence mechanisms, respectively. In order to minimize the uncertainty, model parameters were estimated by combining experimental data of pressure gradient during steady-state and transient. Experiments and theory agree very well and the overall results show a significant increase in foam texture and stability when nanoparticles and surfactant are added to a foam flow in a low permeability porous medium. Data from tests with various nanoparticle concentrations (cn) show that gas apparent viscosity changes with fg and cn. But its optimal value does not vary with cn and it is already attained at fg equal to 0

  11. Wood flour

    Science.gov (United States)

    Craig M. Clemons; Daniel F. Caufield

    2005-01-01

    The term “wood flour” is somewhat ambiguous. Reineke states that the term wood flour “is applied somewhat loosely to wood reduced to finely divided particles approximating those of cereal flours in size, appearance, and texture”. Though its definition is imprecise, the term wood flour is in common use. Practically speaking, wood flour usually refers to wood particles...

  12. Combined analytical and numerical approaches in Dynamic Stability analyses of engineering systems

    Science.gov (United States)

    Náprstek, Jiří

    2015-03-01

    Dynamic Stability is a widely studied area that has attracted many researchers from various disciplines. Although Dynamic Stability is usually associated with mechanics, theoretical physics or other natural and technical disciplines, it is also relevant to social, economic, and philosophical areas of our lives. Therefore, it is useful to occasionally highlight the general aspects of this amazing area, to present some relevant examples and to evaluate its position among the various branches of Rational Mechanics. From this perspective, the aim of this study is to present a brief review concerning the Dynamic Stability problem, its basic definitions and principles, important phenomena, research motivations and applications in engineering. The relationships with relevant systems that are prone to stability loss (encountered in other areas such as physics, other natural sciences and engineering) are also noted. The theoretical background, which is applicable to many disciplines, is presented. In this paper, the most frequently used Dynamic Stability analysis methods are presented in relation to individual dynamic systems that are widely discussed in various engineering branches. In particular, the Lyapunov function and exponent procedures, Routh-Hurwitz, Liénard, and other theorems are outlined together with demonstrations. The possibilities for analytical and numerical procedures are mentioned together with possible feedback from experimental research and testing. The strengths and shortcomings of these approaches are evaluated together with examples of their effective complementing of each other. The systems that are widely encountered in engineering are presented in the form of mathematical models. The analyses of their Dynamic Stability and post-critical behaviour are also presented. The stability limits, bifurcation points, quasi-periodic response processes and chaotic regimes are discussed. The limit cycle existence and stability are examined together with their

  13. Diesel engine performance and emission evaluation using emulsified fuels stabilized by conventional and gemini surfactants

    Energy Technology Data Exchange (ETDEWEB)

    M. Nadeem; C. Rangkuti; K. Anuar; M.R.U. Haq; I.B. Tan; S.S. Shah [Universiti Teknologi PETRONAS, Bandar Seri Iskandar (Malaysia)

    2006-10-15

    Diesel engines exhausting gaseous emission and particulate matter have long been regarded as one of the major air pollution sources, particularly in metropolitan areas, and have been a source of serious public concern for a long time. The emulsification method is not only motivated by cost reduction but is also one of the potentially effective techniques to reduce exhaust emission from diesel engines. Water/diesel (W/D) emulsified formulations are reported to reduce the emissions of NOx, SOx, CO and particulate matter (PM) without compensating the engine's performance. Emulsion fuels with varying contents of water and diesel were prepared and stabilized by conventional and gemini surfactant, respectively. Surfactant's dosage, emulsification time, stirring intensity, emulsifying temperature and mixing time have been reported. Diesel engine performance and exhaust emission was also measured and analyzed with these indigenously prepared emulsified fuels. The obtained experimental results indicate that the emulsions stabilized by gemini surfactant have much finer and better-distributed water droplets as compared to those stabilized by conventional surfactant. A comparative study involving torque, engine brake mean effective pressure (BMEP), specific fuel consumption (SFC), particulate matter (PM), NOx and CO emissions is also reported for neat diesel and emulsified formulations. It was found that there was an insignificant reduction in engine's efficiency but on the other hand there are significant benefits associated with the incorporation of water contents in diesel regarding environmental hazards. The biggest reduction in PM, NOx, CO and SOx emission was achieved by the emulsion stabilized by gemini surfactant containing 15% water contents. 34 refs., 11 figs., 1 tab.

  14. The Stability of Lubricant Oil Acidity of Biogas Fuelled Engine due to Biogas Desulfurization

    Science.gov (United States)

    Gde Tirta Nindhia, Tjokorda; Wayan Surata, I.; Wardana, Ari

    2017-05-01

    This research is established for the purpose of the understanding the stability of the acidity of lubricant oil in biogas fuelled engine due to the absence of hydrogen sulfide (H2S). As was recognized that other than Methane (CH4), there are also other gas impurities in the biogas such as carbon dioxide (CO2), hydrogen sulfide (H2S), moisture (H2O) and ammonia (NH3). Due to H2S contents in the biogas fuel, the engine was found failure. This is caused by corrosion in the combustion chamber due to increase of lubricant acidity. To overcome this problem in practical, the lubricant is increased the pH to basic level with the hope will be decrease to normal value after several time use. Other method is by installing pH measurement sensor in the engine lubricant so that when lubricant is known turn to be acid, then lubricant replacement should be done. In this research, the effect of biogas desulfurization down to zero level to the acidity of lubricant oil in the four stroke engine was carried out with the hope that neutral lubrication oil to be available during running the engine. The result indicates that by eliminating H2S due desulfurization process, effect on stability and neutrality of pH lubricant. By this method the engine safety can be obtained without often replacement the lubricant oil.

  15. Long-term stability and properties of zirconia ceramics for heavy duty diesel engine components

    Science.gov (United States)

    Larsen, D. C.; Adams, J. W.

    1985-01-01

    Physical, mechanical, and thermal properties of commercially available transformation-toughened zirconia are measured. Behavior is related to the material microstructure and phase assemblage. The stability of the materials is assessed after long-term exposure appropriate for diesel engine application. Properties measured included flexure strength, elastic modulus, fracture toughness, creep, thermal shock, thermal expansion, internal friction, and thermal diffusivity. Stability is assessed by measuring the residual property after 1000 hr/1000C static exposure. Additionally static fatigue and thermal fatigue testing is performed. Both yttria-stabilized and magnesia-stabilized materials are compared and contrasted. The major limitations of these materials are short term loss of properties with increasing temperature as the metastable tetragonal phase becomes more stable. Fine grain yttria-stabilized material (TZP) is higher strength and has a more stable microstructure with respect to overaging phenomena. The long-term limitation of Y-TZP is excessive creep deformation. Magnesia-stabilized PSZ has relatively poor stability at elevated temperature. Overaging, decomposition, and/or destabilization effects are observed. The major limitation of Mg-PSZ is controlling unwanted phase changes at elevated temperature.

  16. Stabilization

    Directory of Open Access Journals (Sweden)

    Muhammad H. Al-Malack

    2016-07-01

    Full Text Available Fuel oil flyash (FFA produced in power and water desalination plants firing crude oils in the Kingdom of Saudi Arabia is being disposed in landfills, which increases the burden on the environment, therefore, FFA utilization must be encouraged. In the current research, the effect of adding FFA on the engineering properties of two indigenous soils, namely sand and marl, was investigated. FFA was added at concentrations of 5%, 10% and 15% to both soils with and without the addition of Portland cement. Mixtures of the stabilized soils were thoroughly evaluated using compaction, California Bearing Ratio (CBR, unconfined compressive strength (USC and durability tests. Results of these tests indicated that stabilized sand mixtures could not attain the ACI strength requirements. However, marl was found to satisfy the ACI strength requirement when only 5% of FFA was added together with 5% of cement. When the FFA was increased to 10% and 15%, the mixture’s strength was found to decrease to values below the ACI requirements. Results of the Toxicity Characteristics Leaching Procedure (TCLP, which was performed on samples that passed the ACI requirements, indicated that FFA must be cautiously used in soil stabilization.

  17. Powder Injection Molding of Ceria-Stabilized, Zirconia-Toughened Mullite Parts for UAV Engine Components

    Science.gov (United States)

    Martin, Renee; Vick, Michael; Enneti, Ravi K.; Atre, Sundar V.

    2013-11-01

    Powder injection molding (PIM) of ceria-stabilized, zirconia-toughened mullite composites were investigated in the present article with the goal of obtaining performance enhancement in complex geometries for energy and transportation applications. A powder-polymer mixture (feedstock) was developed and characterized to determine its suitability for fabricating complex components using the PIM process. Test specimens were injection molded and subsequently debound and sintered. The sintered properties indicated suitable properties for engine component applications used in unmanned aerial vehicles (UAVs). The measured feedstock properties were used in computer simulations to assess the mold-filling behavior for a miniature turbine stator. The results from the measurements of rheological and thermal properties of the feedstock combined with the sintered properties of the ceria-stabilized, zirconia-toughened mullite strongly indicate the potential for enhancing the performance of complex geometries used in demanding operating conditions in UAV engines.

  18. Engineering a highly active thermophilic ?-glucosidase to enhance its pH stability and saccharification performance

    OpenAIRE

    Xia, Wei; Xu, Xinxin; Qian, Lichun; Shi, Pengjun; Bai, Yingguo; Luo, Huiying; Ma, Rui; Yao, Bin

    2016-01-01

    Background ?-Glucosidase is an important member of the biomass-degrading enzyme system, and plays vital roles in enzymatic saccharification for biofuels production. Candidates with high activity and great stability over high temperature and varied pHs are always preferred in industrial practice. To achieve cost-effective biomass conversion, exploring natural enzymes, developing high level expression systems and engineering superior mutants are effective approaches commonly used. Results A new...

  19. Cradle-to-Gate Life-Cycle Inventory of Hardboard and Engineered Wood Siding and Trim Produced in North America

    Science.gov (United States)

    Richard D. Bergman

    2015-01-01

    Developing wood product LCI data helps construct product LCAs that are then incorporated into developing whole building LCAs in environmental footprint software such as the Athena Impact Estimator for Buildings (ASMI 2015). Conducting whole building LCAs provide for points that go toward green building certification in rating systems such as LEED v4, Green Globes, and...

  20. Agglomeration, colloidal stability, and magnetic separation of magnetic nanoparticles: collective influences on environmental engineering applications

    Science.gov (United States)

    Yeap, Swee Pin; Lim, JitKang; Ooi, Boon Seng; Ahmad, Abdul Latif

    2017-11-01

    Magnetic nanoparticles (MNPs) which exhibit magnetic and catalytic bifunctionalities have been widely accepted as one of the most promising nanoagents used in water purification processes. However, due to the magnetic dipole-dipole interaction, MNPs can easily lose their colloidal stability and tend to agglomerate. Thus, it is necessary to enhance their colloidal stability in order to maintain the desired high specific surface area. Meanwhile, in order to successfully utilize MNPs for environmental engineering applications, an effective magnetic separation technology has to be developed. This step is to ensure the MNPs that have been used for pollutant removal can be fully reharvested back. Unfortunately, it was recently highlighted that there exists a conflicting role between colloidal stability and magnetic separability of the MNPs, whereby the more colloidally stable the particle is, the harder for it to be magnetically separated. In other words, attaining a win-win scenario in which the MNPs possess both good colloidal stability and fast magnetic separation rate becomes challenging. Such phenomenon has to be thoroughly understood as the colloidal stability and the magnetic separability of MNPs play a pivotal role on affecting their effective implementation in water purification processes. Accordingly, it is the aim of this paper to provide reviews on (i) the colloidal stability and (ii) the magnetic separation of MNPs, as well as to provide insights on (iii) their conflicting relationship based on recent research findings. [Figure not available: see fulltext.

  1. Improved Wood Properties Through Genetic Manipulation: Engineering of Syringyl Lignin in Softwood Species Through Xylem-Specific Expression of Hardwood Syringyl Monolignol Pathway Genes

    Energy Technology Data Exchange (ETDEWEB)

    Chandrashekhar P. Joshi; Vincent L. Chiang

    2009-01-29

    Project Objective: Our long-term goal is to genetically engineer higher value raw materials with desirable wood properties to promote energy efficiency, international competitiveness, and environmental responsiveness of the U.S. forest products industry. The immediate goal of this project was to produce the first higher value softwood raw materials engineered with a wide range of syringyl lignin quantities. Summary: The most important wood property affecting directly the levels of energy, chemical and bleaching requirements for kraft pulp production is lignin. Softwoods contain almost exclusively chemically resistant guaiacyl (G) lignin, whereas hardwoods have more reactive or easily degradable lignins of the guaiacyl (G)-syringyl (S) type. It is also well established that the reactive S lignin component is the key factor that permits much lower effective alkali and temperature, shorter pulping time and less bleaching stages for processing hardwoods than for softwoods. Furthermore, our pulping kinetic study explicitly demonstrated that every increase in one unit of the lignin S/G ratio would roughly double the rate of lignin removal. These are clear evidence that softwoods genetically engineered with S lignin are keys to revolutionizing the energy efficiency and enhancing the environmental performance of this industry. Softwoods and hardwoods share the same genetic mechanisms for the biosynthesis of G lignin. However, in hardwoods, three additional genes branch out from the G-lignin pathway and become specifically engaged in regulating S lignin biosynthesis. In this research, we simultaneously transferred aspen S-specific genes into a model softwood, black spruce, to engineer S lignin.

  2. Local-stability analysis of a low-dissipation heat engine working at maximum power output.

    Science.gov (United States)

    Reyes-Ramírez, I; Gonzalez-Ayala, J; Calvo Hernández, A; Santillán, M

    2017-10-01

    In this paper we address the stability of a low-dissipation (LD) heat engine (HE) under maximum power conditions. The LD system dynamics are analyzed in terms of the contact times between the engine and the external heat reservoirs, which determine the amount of heat exchanged by the system. We study two different scenarios that secure the existence of a single stable steady state. In these scenarios, contact times dynamics are governed by restitutive forces that are linear functions of either the heat amounts exchanged per cycle, or the corresponding heat fluxes. In the first case, according to our results, preferably locating the system irreversibility sources at the hot-reservoir coupling improves the system stability and increases its efficiency. On the other hand, reducing the thermal gradient increases the system efficiency but deteriorates its stability properties, because the restitutive forces are smaller. Additionally, it is possible to compare the relaxation times with the total cycle time and obtain some constraints upon the system dynamics. In the second case, where the restitutive forces are assumed to be linear functions of the heat fluxes, we find that although the partial contact time presents a locally stable stationary value, the total cycle time does not; instead, there exists an infinite collection of steady values located in the neighborhood of the fixed point, along a one-dimensional manifold. Finally, the role of dissipation asymmetries on the efficiency, the stability, and the ratio of the total cycle time to the relaxation time is emphasized.

  3. Fire performance, mechanical strength and dimensional stability of wood flour–polyethylene composites under the influence of different fire retardants

    Directory of Open Access Journals (Sweden)

    Mehdi Roohani

    2017-05-01

    Full Text Available Flammability is one of the most important parameters that often limit the application range of wood plastic composites. Therefore, the improvements of retardancy performance of these products have a considerable impact. The aim of this work was to evaluate the influence of expandable graphite (EG and its combination with aluminum tirhydroxide (ATH, inorganic phosphate (IP and melamine borate (MB on the flammability of wood flour–polyethylene composites. Composites were prepared by the melt compounding method and cone calorimetry as well as limited oxygen index (LOI tests was employed to study their flammability properties. Also, the effect of different fire retardants on the mechanical strength and water uptake of samples were investigated. Cone calorimetry characterization indicated that with incorporation of fire retardans heat release rate and burning rate decrease and char residual as well as the time to ignition increase. These findings ascribed to formation of char layer by fire retardants. The combination of EG and other fire retardants yielded better improvements in flame retardancy in comparison to the sample that has just EG as flame retardant. The LOI test was used to determine the lowest concentration of oxygen at which a material will maintain combustion in a flowing mixture of oxygen and nitrogen. The results showed that inclusion of fire retardants improve the LOI of sample. Furthermore, the presence of fire retardants decreased the tensile and flexural resistance (strength and modules and impact strength of samples, and increased the water absorption as well as thickness swelling. Generally, among the different treatments examined, the EG–ATH retardancy system showed highest potential in flame retardancy of composites.

  4. Wood Dust

    Science.gov (United States)

    Learn about wood dust, which can raise the risk of cancers of the paranasal sinuses and nasal cavity. High amounts of wood dust are produced in sawmills, and in the furniture-making, cabinet-making, and carpentry industries.

  5. Extensions to the time lag models for practical application to rocket engine stability design

    Science.gov (United States)

    Casiano, Matthew J.

    The combustion instability problem in liquid-propellant rocket engines (LREs) has remained a tremendous challenge since their discovery in the 1930s. Improvements are usually made in solving the combustion instability problem primarily using computational fluid dynamics (CFD) and also by testing demonstrator engines. Another approach is to use analytical models. Analytical models can be used such that design, redesign, or improvement of an engine system is feasible in a relatively short period of time. Improvements to the analytical models can greatly aid in design efforts. A thorough literature review is first conducted on liquid-propellant rocket engine (LRE) throttling. Throttling is usually studied in terms of vehicle descent or ballistic missile control however there are many other cases where throttling is important. It was found that combustion instabilities are one of a few major issues that occur during deep throttling (other major issues are heat transfer concerns, performance loss, and pump dynamics). In the past and again recently, gas injected into liquid propellants has shown to be a viable solution to throttle engines and to eliminate some forms of combustion instability. This review uncovered a clever solution that was used to eliminate a chug instability in the Common Extensible Cryogenic Engine (CECE), a modified RL10 engine. A separate review was also conducted on classic time lag combustion instability models. Several new stability models are developed by incorporating important features to the classic and contemporary models, which are commonly used in the aerospace rocket industry. The first two models are extensions of the original Crocco and Cheng concentrated combustion model with feed system contributions. A third new model is an extension to the Wenzel and Szuch double-time lag model also with feed system contributions. The first new model incorporates the appropriate injector acoustic boundary condition which is neglected in contemporary

  6. Wood preservation

    Science.gov (United States)

    Rebecca E. Ibach

    2003-01-01

    When wood is exposed to various environmental conditions, many degradation reactions (biological, ultraviolet, mechanical, moisture, and chemical) can occur. To protect wood from biological degradation, chemical preservatives are applied by nonpressure or pressure treatment. Penetration and retention of a chemical depend upon the wood species and the amount of...

  7. Combustion Stability Verification for the Thrust Chamber Assembly of J-2X Developmental Engines 10001, 10002, and 10003

    Science.gov (United States)

    Morgan, C. J.; Hulka, J. R.; Casiano, M. J.; Kenny, R. J.; Hinerman, T. D.; Scholten, N.

    2015-01-01

    The J-2X engine, a liquid oxygen/liquid hydrogen propellant rocket engine available for future use on the upper stage of the Space Launch System vehicle, has completed testing of three developmental engines at NASA Stennis Space Center. Twenty-one tests of engine E10001 were conducted from June 2011 through September 2012, thirteen tests of the engine E10002 were conducted from February 2013 through September 2013, and twelve tests of engine E10003 were conducted from November 2013 to April 2014. Verification of combustion stability of the thrust chamber assembly was conducted by perturbing each of the three developmental engines. The primary mechanism for combustion stability verification was examining the response caused by an artificial perturbation (bomb) in the main combustion chamber, i.e., dynamic combustion stability rating. No dynamic instabilities were observed in the TCA, although a few conditions were not bombed. Additional requirements, included to guard against spontaneous instability or rough combustion, were also investigated. Under certain conditions, discrete responses were observed in the dynamic pressure data. The discrete responses were of low amplitude and posed minimal risk to safe engine operability. Rough combustion analyses showed that all three engines met requirements for broad-banded frequency oscillations. Start and shutdown transient chug oscillations were also examined to assess the overall stability characteristics, with no major issues observed.

  8. Characterization of Thermal Stability of Synthetic and Semi-Synthetic Engine Oils

    Directory of Open Access Journals (Sweden)

    Anand Kumar Tripathi

    2015-03-01

    Full Text Available Engine oils undergo oxidative degradation and wears out during service. Hence it is important to characterize ageing of engine oils at different simulated conditions to evaluate the performance of existing oils and also design new formulations. This work focuses on characterizing the thermo-oxidative degradation of synthetic and semi-synthetic engine oils aged at 120, 149 and 200 °C. Apparent activation energy of decomposition of aged oils evaluated using the isoconversional Kissinger-Akahira-Sunose technique was used as a thermal stability marker. The temporal variation of stability at different ageing temperatures was corroborated with kinematic viscosity, oxidation, sulfation and nitration indices, total base number, antiwear additive content and molecular structure of the organic species present in the oils. At the lowest temperature employed, synthetic oil underwent higher rate of oxidation, while semi-synthetic oil was stable for longer time periods. At higher temperatures, the initial rate of change of average apparent activation energy of synthetic oil correlated well with a similar variation in oxidation number. A mixture of long chain linear, branched, and cyclic hydrocarbons were observed when semi-synthetic oil was degraded at higher temperatures.

  9. Landsat Time-series for the Masses: Predicting Wood Biomass Growth from Tree-rings Using Departures from Mean Phenology in Google Earth Engine

    Science.gov (United States)

    Foster, J. R.; D'Amato, A. W.; Itter, M.; Reinikainen, M.; Curzon, M.

    2017-12-01

    The terrestrial carbon cycle is perturbed when disturbances remove leaf biomass from the forest canopy during the growing season. Changes in foliar biomass arise from defoliation caused by insects, disease, drought, frost or human management. As ephemeral disturbances, these often go undetected and their significance to models that predict forest growth from climatic drivers remains unknown. Here, we seek to distinguish the roles of weather vs. canopy disturbance on forest growth by using dense Landsat time-series to quantify departures in mean phenology that in turn predict changes in leaf biomass. We estimated a foliar biomass index (FBMI) from 1984-2016, and predict plot-level wood growth over 28 years on 156 tree-ring monitoring plots in Minnesota, USA. We accessed the entire Landsat archive (sensors 4, 5 & 7) to compute FBMI using Google Earth Engine's cloud computing platform (GEE). GEE allows this pixel-level approach to be applied at any location; a feature we demonstrate with published wood-growth data from flux tower sites. Our Bayesian models predicted biomass changes from tree-ring plots as a function of Landsat FBMI and annual climate data. We expected model parameters to vary by tree functional groups defined by differences in xylem anatomy and leaf longevity, two traits with linkages to phenology, as reported in a recent review. We found that Landsat FBMI was a surprisingly strong predictor of aggregate wood-growth, explaining up to 80% of annual growth variation for some deciduous plots. Growth responses to canopy disturbance varied among tree functional groups, and the importance of some seasonal climate metrics diminished or changed sign when FBMI was included (e.g. fall and spring climatic water deficit), while others remained unchanged (current and lagged summer deficit). Insights emerging from these models can clear up sources of persistent uncertainty and open a new frontier for models of forest productivity.

  10. Engineering feasibility analysis for in-situ stabilization of Burrell Township site residues

    International Nuclear Information System (INIS)

    1982-11-01

    The Burrell Township site, located in western Pennsylvania, received approximately 11,600 tons of radioactively-contaminated material in late 1956 and early 1957 from the Vitro Manufacturing Company's operations in Canonsburg, Pennsylvania. WESTON was requested to conduct an engineering study to determine the feasibility of stabilizing the site in accordance with the US Environmental Protection Agency's (EPA) interim and proposed standards (45 FR 27366--27368, April 22, 1980, and 46 FR 2556--2563, January 9, 1981). The scope of this study is limited to those alternatives that can be implemented on the site and will not require removal and offsite disposal of radioactively-contaminated material. Four alternatives for control of the radioactive material at the Burrell site were considered and evaluated, as follows: 1. Site stabilization and closure. 2. Site control and containment. 3. Waste excavation and encapsulation. 4. Waste excavation, incineration, and encapsulation. 2 refs., 32 figs., 12 tabs

  11. Engineering feasibility analysis for in-situ stabilization of Burrell Township site residues. [UMTRA

    Energy Technology Data Exchange (ETDEWEB)

    1982-11-01

    The Burrell Township site, located in western Pennsylvania, received approximately 11,600 tons of radioactively-contaminated material in late 1956 and early 1957 from the Vitro Manufacturing Company's operations in Canonsburg, Pennsylvania. WESTON was requested to conduct an engineering study to determine the feasibility of stabilizing the site in accordance with the US Environmental Protection Agency's (EPA) interim and proposed standards (45 FR 27366--27368, April 22, 1980, and 46 FR 2556--2563, January 9, 1981). The scope of this study is limited to those alternatives that can be implemented on the site and will not require removal and offsite disposal of radioactively-contaminated material. Four alternatives for control of the radioactive material at the Burrell site were considered and evaluated, as follows: 1. Site stabilization and closure. 2. Site control and containment. 3. Waste excavation and encapsulation. 4. Waste excavation, incineration, and encapsulation. 2 refs., 32 figs., 12 tabs.

  12. Investigation of the long term stability and corrosion resistance of engineering barriers

    International Nuclear Information System (INIS)

    Aoyama, Eri; Tachikawa, Hirokazu; Shimizu, Akihiko

    2005-03-01

    The Japan Nuclear Cycle Development Institute submitted 'Second Progress Report on Research and Development for the Geological Disposal of HLW in Japan' to the Japanese government. This report contains investigations of the long term behavior of alteration of bentonite, and of the corrosion life time of overpack on the basis of experimental data and past research, assuming the ranging geological environment of Japan. However some subjects, such as the behavior of the bentonite and overpack under high pH conditions and the behavior of the engineering barrier with change of near-field environmental condition with time for promoting reliability have still been left. To take into account these conditions, expert committees composed of clay science and metal corrosion science experts were established in the Nuclear Safety Research Association and past research outcomes and the theory of safety assessment were investigated from the view points of long term stability and corrosion resistance of engineering barrier. (author)

  13. Investigation and technical reviews of the long term stability and corrosion resistance of engineering barriers

    International Nuclear Information System (INIS)

    Tachikawa, Hirokazu

    2004-03-01

    The Japan Nuclear Fuel Cycle Development Institute submitted 'Second Progress Report on Research and Development for the Geological Disposal of HLW in Japan' to the Japanese government. This report contains investigations of the long term behavior of alteration of bentonite, and of the corrosion life time of overpack on the basis of experimental data and past research, assuming the ranging geological environment of Japan. However some subjects, such as the behavior of the bentonite and overpack under high pH conditions and the behavior of the engineering barrier with change of near-field environmental condition with time for promoting reliability have still been left. To take into account these conditions, expert committees composed of clay science and metal corrosion science experts were established in the Nuclear Safety Research Association and past research outcomes and the theory of safety assessment were investigated and technically reviewed from the view points of long term stability and corrosion resistance of engineering buffer materials. (author)

  14. Influence of diesel engine combustion on the rupture strength of partially stabilized zirconia

    International Nuclear Information System (INIS)

    Brinkman, C.R.; Begun, G.M.; Cavin, O.B.; Foster, B.E.; Graves, R.L.; Kahl, W.K.; Liu, K.C.; Simpson, W.A.

    1989-01-01

    Results are reported for tests on partially stabilized zirconia (PSZ-TS and MS grade) bars exposed in the combustion chambers of two operating single-cylinder 0.825-L diesel engines. Specifics of test conditions and procedures are presented. Subsequent to exposure, the bars were subjected to four-point bending and the rupture strengths determined. The TS grade showed a decrease in average strength of 32%, while the strength of the MS grade decreased by about 9% in comparison to average behavior of unaged material. Results of X-ray diffraction analysis, Raman spectroscopy, isothermal aging studies, and ceramographic characterization are given to define reasons for material degradation

  15. Stabilizing the CH2 Domain of an Antibody by Engineering in an Enhanced Aromatic Sequon.

    Science.gov (United States)

    Chen, Wentao; Kong, Leopold; Connelly, Stephen; Dendle, Julia M; Liu, Yu; Wilson, Ian A; Powers, Evan T; Kelly, Jeffery W

    2016-07-15

    Monoclonal antibodies (mAbs) exhibiting highly selective binding to a protein target constitute a large and growing proportion of the therapeutics market. Aggregation of mAbs results in the loss of their therapeutic efficacy and can result in deleterious immune responses. The CH2 domain comprising part of the Fc portion of Immunoglobulin G (IgG) is typically the least stable domain in IgG-type antibodies and therefore influences their aggregation propensity. We stabilized the CH2 domain by engineering an enhanced aromatic sequon (EAS) into the N-glycosylated C'E loop and observed a 4.8 °C increase in the melting temperature of the purified IgG1 Fc fragment. This EAS-stabilized CH2 domain also conferred enhanced stability against thermal and low pH induced aggregation in the context of a full-length monoclonal IgG1 antibody. The crystal structure of the EAS-stabilized (Q295F/Y296A) IgG1 Fc fragment confirms the design principle, i.e., the importance of the GlcNAc1•F295 interaction, and surprisingly reveals that the core fucose attached to GlcNAc1 also engages in an interaction with F295. Inhibition of core fucosylation confirms the contribution of the fucose-Phe interaction to the stabilization. The Q295F/Y296A mutations also modulate the binding affinity of the full-length antibody to Fc receptors by decreasing the binding to low affinity Fc gamma receptors (FcγRIIa, FcγRIIIa, and FcγRIIIb), while maintaining wild-type binding affinity to FcRn and FcγRI. Our results demonstrate that engineering an EAS into the N-glycosylated reverse turn on the C'E loop leads to stabilizing N-glycan-protein interactions in antibodies and that this modification modulates antibody-Fc receptor binding.

  16. Wood composites

    Science.gov (United States)

    Lars Berglund; Roger M. Rowell

    2005-01-01

    A composite can be defined as two or more elements held together by a matrix. By this definition, what we call “solid wood” is a composite. Solid wood is a three-dimensional composite composed of cellulose, hemicelluloses and lignin (with smaller amounts of inorganics and extractives), held together by a lignin matrix. The advantages of developing wood composites are (...

  17. Wood and Other Materials Used to Construct Nonresidential Buildings - Canada

    Science.gov (United States)

    David B. McKeever; Joe Elling

    2014-01-01

    Low-rise nonresidential building construction is an important market in Canada for lumber, engineered wood products, structural wood panels, and nonstructural wood panels. This report examines wood products consumption in 2012 for construction of selected low-rise nonresidential buildings types that have six or fewer stories. Buildings with more than six stories are...

  18. Soil aggregate stability as an indicator for eco-engineering effectiveness?

    Science.gov (United States)

    Graf, Frank

    2015-04-01

    Eco-engineering aims at stabilising soil and slopes by applying technical and biological measures. Engineering structures are commonly well defined, immediately usable and operative, and their stability effects quantifiable and verifiable. Differently, the use of plants requires more restrictive boundary conditions and the protection potential is rarely easily calculable and develop-ing as a function of growth rate. Although the use of vegetation is widely appreciated and their stabilising effect recognised, there is an increasing demand on sound facts on its efficiency, in particular, in relation to time. Conclusively, a certain necessity has been recognised to monitor, assess and quantify the effectiveness of ecological restora-tion measures in order to facilitate the transfer of technology and knowledge. Recent theoretical models emphasize the im-portance of taking an integrated monitoring approach that considers multiple variables. However, limited financial and time resources often prevent such comprehensive assessments. A solution to this problem may be to use integrated indicators that reflect multiple aspects and, therefore, allow extensive information on ecosystem status to be gathered in a relatively short time. Among various other indicators, such as fractal dimension of soil particle size distribution or microbiological parameters, soil aggregate stability seems the most appropriate indicator with regard to protecting slopes from superficial soil failure as it is critical to both plant growth and soil structure. Soil aggregation processes play a crucial role in re-establishing soil structure and function and, conclusively, for successful and sustainable re-colonisation. Whereas the key role of soil aggregate stability in ecosystem functioning is well known concerning water, gas, and nutrient fluxes, only limited information is available with regard to soil mechanical and geotechnical aspects. Correspondingly, in the last couple of years several studies

  19. Dimensional stability of wood-plastic composites reinforced with potassium methyl siliconate modified fiber and sawdust made from beetle-killed trees

    Science.gov (United States)

    Cheng Piao; Zhiyong Cai; Nicole M. Stark; Charles J. Montezun

    2014-01-01

    Wood fromtwovarieties of beetle-killed trees was used to fabricate wood–plastic composites. Loblolly pine and lodgepole pine beetle-killed trees were defibrated mechanically and thermomechanically, respectively, into fiber. Fiber and sawdust produced from the trees were modified with potassium methyl siliconate (PMS) and injection-molded into fiber/sawdust reinforced...

  20. Toward a Stakeholder Perspective on Social Stability Risk of Large Hydraulic Engineering Projects in China: A Social Network Analysis

    Directory of Open Access Journals (Sweden)

    Zhengqi He

    2018-04-01

    Full Text Available In China, large hydraulic engineering projects have made a great contribution to social economic development; at the same time, they also lead to social risks that affect social stability. The pluralism of stakeholders in large hydraulic engineering projects and the complex interrelationship among stakeholders are the important factors affecting social stability risk. Previous studies of social stability risk have mainly focused on risk identification and risk assessment, without considering the relationships among stakeholders and their linkages of risks. For large hydraulic engineering projects, this paper investigated the relevant risk factors and their interrelationships through a literature review and interviews that represented stakeholder perspectives. The key social stability risk factors were identified based on social network analysis. A multi-channel project financial system, a perfect interest compensation mechanism, an efficient prevention mechanism of group events, and a complete project schedule control system were proposed to mitigate the social stability risks. This study combined stakeholder management with risk management by using social network analysis, providing reference for the social stability risk management of large engineering projects in China.

  1. Effects of combustion particles - Comparison of health relevance of wood fires and diesel engines; Wirkung von Verbrennungspartikeln. Vergleich der Gesundheitsrelevanz von Holzfeuerungen und Dieselmotoren

    Energy Technology Data Exchange (ETDEWEB)

    Klippel, N.; Nussbaumer, T.

    2007-03-15

    This comprehensive final report for the Swiss Federal Office of Energy (SFOE) takes a look at the relevance of fine-dust particles (PM10, particulate matter smaller than 10 microns) emitted from wood-fired boilers in comparison with soot from diesel engines. Medicinal basics with reference to the particles concerned are explained, including the physiology of the human respiratory system, its defence mechanisms against fine dust as well as detrimental health effects to the nose, lungs and cardio-vascular system. Also, allergic reactions and effects at cell level are discussed. The mechanisms involved in the emission of the particles in ovens and diesel engines are examined and compared. The methods used to take samples of the particles are explained and the results of cell-tests are presented and discussed. Estimates of the particle concentrations in the lung are presented and comparisons are made of loading during smog-periods. The report is rounded off with a comprehensive list of literature on the subject.

  2. Furniture wood wastes: Experimental property characterisation and burning tests

    International Nuclear Information System (INIS)

    Tatano, Fabio; Barbadoro, Luca; Mangani, Giovanna; Pretelli, Silvia; Tombari, Lucia; Mangani, Filippo

    2009-01-01

    Referring to the industrial wood waste category (as dominant in the provincial district of Pesaro-Urbino, Marche Region, Italy), this paper deals with the experimental characterisation and the carrying out of non-controlled burning tests (at lab- and pilot-scale) for selected 'raw' and primarily 'engineered' ('composite') wood wastes. The property characterisation has primarily revealed the following aspects: potential influence on moisture content of local weather conditions at outdoor wood waste storage sites; generally, higher ash contents in 'engineered' wood wastes as compared with 'raw' wood wastes; and relatively high energy content values of 'engineered' wood wastes (ranging on the whole from 3675 to 5105 kcal kg -1 for HHV, and from 3304 to 4634 kcal kg -1 for LHV). The smoke qualitative analysis of non-controlled lab-scale burning tests has primarily revealed: the presence of specific organic compounds indicative of incomplete wood combustion; the presence exclusively in 'engineered' wood burning tests of pyrroles and amines, as well as the additional presence (as compared with 'raw' wood burning) of further phenolic and containing nitrogen compounds; and the potential environmental impact of incomplete industrial wood burning on the photochemical smog phenomenon. Finally, non-controlled pilot-scale burning tests have primarily given the following findings: emission presence of carbon monoxide indicative of incomplete wood combustion; higher nitrogen oxide emission values detected in 'engineered' wood burning tests as compared with 'raw' wood burning test; and considerable generation of the respirable PM 1 fraction during incomplete industrial wood burning.

  3. Processing bulk natural wood into a high-performance structural material

    Science.gov (United States)

    Song, Jianwei; Chen, Chaoji; Zhu, Shuze; Zhu, Mingwei; Dai, Jiaqi; Ray, Upamanyu; Li, Yiju; Kuang, Yudi; Li, Yongfeng; Quispe, Nelson; Yao, Yonggang; Gong, Amy; Leiste, Ulrich H.; Bruck, Hugh A.; Zhu, J. Y.; Vellore, Azhar; Li, Heng; Minus, Marilyn L.; Jia, Zheng; Martini, Ashlie; Li, Teng; Hu, Liangbing

    2018-02-01

    Synthetic structural materials with exceptional mechanical performance suffer from either large weight and adverse environmental impact (for example, steels and alloys) or complex manufacturing processes and thus high cost (for example, polymer-based and biomimetic composites). Natural wood is a low-cost and abundant material and has been used for millennia as a structural material for building and furniture construction. However, the mechanical performance of natural wood (its strength and toughness) is unsatisfactory for many advanced engineering structures and applications. Pre-treatment with steam, heat, ammonia or cold rolling followed by densification has led to the enhanced mechanical performance of natural wood. However, the existing methods result in incomplete densification and lack dimensional stability, particularly in response to humid environments, and wood treated in these ways can expand and weaken. Here we report a simple and effective strategy to transform bulk natural wood directly into a high-performance structural material with a more than tenfold increase in strength, toughness and ballistic resistance and with greater dimensional stability. Our two-step process involves the partial removal of lignin and hemicellulose from the natural wood via a boiling process in an aqueous mixture of NaOH and Na2SO3 followed by hot-pressing, leading to the total collapse of cell walls and the complete densification of the natural wood with highly aligned cellulose nanofibres. This strategy is shown to be universally effective for various species of wood. Our processed wood has a specific strength higher than that of most structural metals and alloys, making it a low-cost, high-performance, lightweight alternative.

  4. Characterization of Wood-Plastic Composites Made with Different Lignocellulosic Materials that Vary in Their Morphology, Chemical Composition and Thermal Stability

    Directory of Open Access Journals (Sweden)

    Ke-Chang Hung

    2017-12-01

    Full Text Available In this study, four kinds of lignocellulosic fibers (LFs, namely, those from Chinese fir (Cunninghamia lanceolata, Taiwan red pine (Pinus taiwanensis, India-charcoal trema (Trema orientalis and makino bamboo (Phyllostachys makinoi, were selected as reinforcements and incorporated into high-density polyethylene (HDPE to manufacture wood-plastic composites (WPCs by a flat platen pressing process. In addition to comparing the differences in the physico-mechanical properties of these composites, their chemical compositions were evaluated and their thermal decomposition kinetics were analyzed to investigate the effects of the lignocellulosic species on the properties of the WPCs. The results showed that the WPC made with Chinese fir displayed a typical M-shaped vertical density profile due to the high aspect ratio of its LFs, while a flat vertical density profile was observed for the WPCs made with other LFs. Thus, the WPC made with Chinese fir exhibited higher flexural properties and lower internal bond strength (IB than other WPCs. In addition, the Taiwan red pine contained the lowest holocellulose content and the highest extractives and α-cellulose contents, which gave the resulting WPC lower water absorption and flexural properties. On the other hand, consistent with the flexural properties, the results of thermal decomposition kinetic analysis showed that the activation energy of the LFs at 10% of the conversion rate increased in the order of Taiwan red pine (146–161 kJ/mol, makino bamboo (158–175 kJ/mol, India-charcoal trema (185–194 kJ/mol and Chinese fir (194–202 kJ/mol. These results indicate that the morphology, chemical composition and thermal stability of the LFs can have a substantial impact on the physico-mechanical properties of the resulting WPCs.

  5. Effect of Compaction Energy on Engineering Properties of Fly Ash –Granite Dust Stabilized Expansive Soil

    OpenAIRE

    Akshaya Kumar Sabat; Ranjan Kumar Moharana

    2015-01-01

    The effects of compaction energy on engineering properties of an expansive soil stabilized with optimum percentage of fly ash-granite dust have been discussed in this paper. Expansive soil stabilized with optimum percentage of fly ash-granite dust was compacted with five compaction energy levels. Maximum dry density and optimum moisture content corresponding to each energy level were determined. Based on these maximum dry density and optimum moisture content, samples were prepared for unco...

  6. Interface engineering of perovskite solar cells with multifunctional polymer interlayer toward improved performance and stability

    Science.gov (United States)

    Huang, Li-Bo; Su, Pei-Yang; Liu, Jun-Min; Huang, Jian-Feng; Chen, Yi-Fan; Qin, Su; Guo, Jing; Xu, Yao-Wei; Su, Cheng-Yong

    2018-02-01

    This work proposes a new perovskite solar cell structure by inserting a polymer interlayer between perovskite and hole transporting material (HTM) to minimize the interface losses via interface engineering. The multifunctional interlayers improve the photovoltaic efficiency and device stability by shielding perovskite from moisture, suppressing charge combination, and promoting hole transport. The five different polymer layers are utilized to investigate the relationships of polymer structure, layer morphology and cell performance systematically. It is found that a reliable power conversion efficiency exceeding 19.0% is realized based on P3HT/spiro-OMeTAD composite structure, surpassing that of pure spiro-OMeTAD (15.0%). Moreover, the device with P3HT interlayer shows more brilliant long-term stability than that without interlayer when exposed into moisture. The enhanced device performance based on P3HT interlayer compared with the other polymers can be ascribed to the long hydrophobic alkyl chains and the small molecule monomers of P3HT, which contribute to self-assembly of the polymers into insulating layers and formation of the efficient π-π stacking in polymer/spiro-OMeTAD interface simultaneously. This study provides a practical route for the integration of a new class of easily-accessible, solution-processed interfacial polymer materials for high-performance and long-time stable PSC.

  7. RP-2 Thermal Stability and Heat Transfer Investigation for Hydrocarbon Boost Engines

    Science.gov (United States)

    VanNoord, J. L.; Stiegemeier, B. R.

    2010-01-01

    A series of electrically heated tube tests were performed at the NASA Glenn Research Center s Heated Tube Facility to investigate the use of RP-2 as a fuel for next generation regeneratively cooled hydrocarbon boost engines. The effect that test duration, operating condition and test piece material have on the overall thermal stability and materials compatibility characteristics of RP-2 were evaluated using copper and 304 stainless steel test sections. The copper tests were run at 1000 psia, heat flux up to 6.0 Btu/in.2-sec, and wall temperatures up to 1180 F. Preliminary results, using measured wall temperature as an indirect indicator of the carbon deposition process, show that in copper test pieces above approximately 850 F, RP-2 begins to undergo thermal decomposition resulting in local carbon deposits. Wall temperature traces show significant local temperature increases followed by near instantaneous drops which have been attributed to the carbon deposition/shedding process in previous investigations. Data reduction is currently underway for the stainless steel test sections and carbon deposition measurements will be performed in the future for all test sections used in this investigation. In conjunction with the existing thermal stability database, these findings give insight into the feasibility of cooling a long life, high performance, high-pressure liquid rocket combustor and nozzle with RP-2.

  8. Strain-engineering stabilization of BaTi O3 -based polar metals

    Science.gov (United States)

    Ma, Chao; Jin, Kui-juan; Ge, Chen; Yang, Guo-zhen

    2018-03-01

    Polar metals, which possess ferroelectriclike polar structure and conductivity simultaneously, have attracted wide interest since the first solid example, LiOs O3 (below 140 K), was discovered. However, the lack of room-temperature polar metals hinders further research and applications. Thus abundant properties of polar metals are unexplored. Here, with first-principles calculations, we report that the polar metal phase can be stabilized in the strain-engineered BaTi O3 with electron doping. The mechanism relates to the competition between the shifting of the t2 g energy levels and the narrowing of their bandwidth. Surprisingly, it is predicted that the ferroelectric-to-paraelectric transition temperature can be increased by electron doping when the strain is large enough, which holds potential for room-temperature polar metals. Our results indicate that strain engineering is a promising way to achieve BaTi O3 -based polar metals, and they should have practical significance for obtaining easily accessible, ecofriendly, and potential room-temperature polar metals.

  9. Thermal Properties of Wood-Plastic Composites Prepared from Hemicellulose-extracted Wood Flour

    Directory of Open Access Journals (Sweden)

    A.A. Enayati

    2013-01-01

    Full Text Available Hemicellulose of Southern Yellow Pine wood spices was extracted by pressurized hot water at three different temperatures: 140°C, 155°C and 170°C. Compounding with PP (polypropylene was performed by extrusion after preparing wood flour and sieving to determine its mesh size. The ratio of wood to polymer was 50:50 based on oven-dry weight of wood flour. All extraction treatments and control samples were compounded under two sets of conditions, without and with 2% MAPP as coupling agent. Injection molding was used to make tensile test samples (dogbone from the pellets made by extrusion. Thermal properties of wood-plastic composites were studied by TGA and DSC while the thermal stability of pretreated wood flours, PP and MAPP were studied by TGA as well. The greater weight loss of wood materials was an indication that higher treatment temperature increases the extractability of hemicellulose. The removal of hemicellulose by extraction improves thermal stability of wood flour, especially for extraction at 170°C. Wood-plastic composites made from extracted fibers at 170°C showed the highest thermal stability. Coupling agent did not have a significant effect on thermal stability but it improved the degree of crystallinity of the composites.Surface roughness of wood fiber increased after treatment. Extraction of hemicellulose increased the degree of crystallinity but it was not significant except for samples from treated wood flour at 170°C and with MAPP.

  10. Wood preservation

    Science.gov (United States)

    Kevin Archer; Stan Lebow

    2006-01-01

    Wood preservation can be interpreted to mean protection from fire, chemical degradation, mechanical wear, weathering, as well as biological attack. In this chapter, the term preservation is applied more restrictively to protection from biological hazards.

  11. Transport and retention of surfactant- and polymer-stabilized engineered silver nanoparticles in silicate-dominated aquifer material

    Science.gov (United States)

    Packed column experiments were conducted to investigate the transport and blocking behavior of surfactant- and polymer-stabilized engineered silver nanoparticles (Ag-ENPs) in saturated natural aquifer material with varying silt and clay content, background solution chemistry, and flow velocity. Brea...

  12. Engineering Enzyme Stability and Resistance to an Organic Cosolvent by Modification of Residues in the Access Tunnel

    Czech Academy of Sciences Publication Activity Database

    Koudeláková, T.; Chaloupková, R.; Březovský, J.; Prokop, Z.; Šebestová, E.; Hesseler, M.; Khabiri, Morteza; Plevaka, M.; Kulik, D.; Kutá-Smatanová, Ivana; Řezáčová, Pavlína; Ettrich, Rüdiger; Bornscheuer, U.T.; Damborský, J.

    2013-01-01

    Roč. 52, č. 7 (2013), s. 1959-1963 ISSN 1433-7851 R&D Projects: GA MŠk(CZ) LC06010 Institutional support: RVO:67179843 ; RVO:68378050 Keywords : directed evolution * enzyme catalysis * enzymes * protein engineering * protein stability Subject RIV: CE - Biochemistry; EB - Genetics ; Molecular Biology (UMG-J) Impact factor: 11.336, year: 2013

  13. Engineering solutions to the long-term stabilization and isolation of uranium mill tailings in the United States

    International Nuclear Information System (INIS)

    Sanders, D.R.; Lommler, J.C.

    1995-01-01

    Engineering solutions to the safe and environmentally protective disposal and isolation of uranium mill tailings in the US include many factors. Cover design, materials selection, civil engineering, erosive forces, and cost effectiveness are only a few of those factors described in this paper. The systems approach to the engineering solutions employed in the US is described, with emphasis on the standards prescribed for the Uranium Mill Tailings Remedial Action Project. Stabilization and isolation of the tailings from humans and the environment are the primary goals of the US uranium mill tailings control standards. The performance of cover designs with respect to water infiltration, radon exhalation, geotechnical stability, erosion protection, human and animal intrusion prevention, and longevity are addressed. The need for and frequency of surveillance efforts to ensure continued disposal system performance are also assessed

  14. Interactive Effects of Climate Change and Decomposer Communities on the Stabilization of Wood-Derived Carbon Pools: Catalyst for a New Study

    Energy Technology Data Exchange (ETDEWEB)

    Resh, Sigrid C. [Michigan Technological Univ., Houghton, MI (United States)

    2014-11-17

    Globally, forest soils store ~two-thirds as much carbon (C) as the atmosphere. Although wood makes up the majority of forest biomass, the importance of wood contributions to soil C pools is unknown. Even with recent advances in the mechanistic understanding of soil processes, integrative studies tracing C input pathways and biological fluxes within and from soils are lacking. Therefore, our research objectives were to assess the impact of different fungal decay pathways (i.e., white-rot versus brown-rot)—in interaction with wood quality, soil temperature, wood location (i.e., soil surface and buried in mineral soil), and soil texture—on the transformation of woody material into soil CO2 efflux, dissolved organic carbon (DOC), and soil C pools. The use of 13C-depleted woody biomass harvested from the Rhinelander, WI free-air carbon dioxide enrichment (Aspen-FACE) experiment affords the unique opportunity to distinguish the wood-derived C from other soil C fluxes and pools. We established 168 treatment plots across six field sites (three sand and three loam textured soil). Treatment plots consisted of full-factorial design with the following treatments: 1. Wood chips from elevated CO2, elevated CO2 + O3, or ambient atmosphere AspenFACE treatments; 2. Inoculated with white rot (Bjerkandera adusta) or brown rot (Gloeophyllum sepiarium) pure fungal cultures, or the original suite of endemic microbial community on the logs; and 3. Buried (15cm in soil as a proxy for coarse roots) or surface applied wood chips. We also created a warming treatment using open-topped, passive warming chambers on a subset of the above treatments. Control plots with no added wood (“no chip control”) were incorporated into the research design. Soils were sampled for initial δ13C values, CN concentrations, and bulk density. A subset of plots were instrumented with lysimeters for sampling soil water and temperature data

  15. Chemical interaction of radioactive waste with clay engineered barriers: stability of the resulting immobilizer phase

    International Nuclear Information System (INIS)

    Galunin, Evgeny; Vidal, Miquel; Alba, Maria D.

    2010-01-01

    Document available in extended abstract form only. High-level radioactive waste containing long-lived actinides (Pu, Np, Am) originates from the spent fuel from nuclear power plants. The deep geological disposal is the main permanent solution that is considered by the scientific community as the most promising method for the long-term management of the radioactive waste. In a deep geological repository (DGR), which is based on an engineered and natural Multi-barrier system, the construction of engineered barriers composed of clays and concrete materials around the canister seems to be the most effective approach for the radionuclide immobilization. It has been recently observed that a chemical reaction takes place over a wide pH range when putting into contact a smectite sample with the salt of a rare-earth element (REE, actinide simulator) in an aqueous solution under pressure and temperature conditions compatible with the DGR scenario. The chemical reaction leads to the formation of an insoluble, persistent rare-earth di-silicate phase, REE 2 Si 2 O 7 . Taking into account that the di-silicate phase formation could be responsible of the success of the clay barrier once the smectite has lost its swelling and cation exchange capacity, its stability (e.g., the di-silicate dissolution at different pH values) should be considered as an influencing factor for the long-term performance of the DGR. Although to know the di-silicate phase stability in the DGR is a key aspect to evaluate its role in the overall performance of the DGR, it has not yet been found detailed explanation on the effect of the REE ionic radius and the pH on the di-silicate stability. Thus, the main goal of the present study is to investigate the effect of the REE ionic radius on the leaching of different REE (Sc, Lu, Y) and thus on the dissolution of REE 2 Si 2 O 7 (REE = Sc, Lu, Y) over a wide pH range. Scandium, lutetium and yttrium di-silicates were synthesized following the sol-gel method and

  16. Wood as an adherend

    Science.gov (United States)

    Bryan H. River; Charles B. Vick; Robert H. Gillespie

    1991-01-01

    Wood is a porous, permeable, hygroscopic, orthotropic, biological composite material of extreme chemical diversity and physical intricacy. Table 1.1 provides an overview of the may variables, including wood variables, that bear on the bonding and performance of wood in wood joints and wood-based materials. Of particular note is the fact that wood properties vary...

  17. Combustion Stability of the Gas Generator Assembly from J-2X Engine E10001 and Powerpack Tests

    Science.gov (United States)

    Hulka, J. R.; Kenny, R. L.; Casiano, M. J.

    2013-01-01

    Testing of a powerpack configuration (turbomachinery and gas generator assembly) and the first complete engine system of the liquid oxygen/liquid hydrogen propellant J-2X rocket engine have been completed at the NASA Stennis Space Center. The combustion stability characteristics of the gas generator assemblies on these two systems are of interest for reporting since considerable effort was expended to eliminate combustion instability during early development of the gas generator assembly with workhorse hardware. Comparing the final workhorse gas generator assembly development test data to the powerpack and engine system test data provides an opportunity to investigate how the nearly identical configurations of gas generator assemblies operate with two very different propellant supply systems one the autonomous pressure-fed test configuration on the workhorse development test stand, the other the pump-fed configurations on the powerpack and engine systems. The development of the gas generator assembly and the elimination of the combustion instability on the pressure-fed workhorse test stand have been reported extensively in the two previous Liquid Propulsion Subcommittee meetings 1-7. The powerpack and engine system testing have been conducted from mid-2011 through 2012. All tests of the powerpack and engine system gas generator systems to date have been stable. However, measureable dynamic behavior, similar to that observed on the pressure-fed test stand and reported in Ref. [6] and attributed to an injection-coupled response, has appeared in both powerpack and engine system tests. As discussed in Ref. [6], these injection-coupled responses are influenced by the interaction of the combustion chamber with a branch pipe in the hot gas duct that supplies gaseous helium to pre-spin the turbine during the start transient. This paper presents the powerpack and engine system gas generator test data, compares these data to the development test data, and provides additional

  18. Adhesives for Achieving Durable Bonds with Acetylated Wood

    Directory of Open Access Journals (Sweden)

    Charles R. Frihart

    2017-12-01

    Full Text Available Acetylation of wood imparts moisture durability, decay resistance, and dimensional stability to wood; however, making durable adhesive bonds with acetylated wood can be more difficult than with unmodified wood. The usual explanation is that the acetylated surface has fewer hydroxyl groups, resulting in a harder-to-wet surface and in fewer hydrogen bonds between wood and adhesive. This concept was evaluated using four different adhesives (resorcinol–formaldehyde, emulsion polymer isocyanate, epoxy, and melamine–formaldehyde with unmodified wood, acetylated wood, and acetylated wood that had been planed. Strikingly, acetylation did not hinder adhesive bonds with a waterborne resorcinol–formaldehyde adhesive that bonded equally well to both unmodified and acetylated yellow poplar. An epoxy adhesive bonded better to the acetylated wood than to the unmodified wood, in contrast to an emulsion polymer isocyanate, which gave less durable bonds to acetylated than to unmodified wood. Planing of the acetylated wood surface prior to bonding reduced bond durability for the epoxy adhesive and increased the amount of surface hydroxyl groups, as measured using X-ray photoelectron spectroscopic analysis of the trifluoroacetic anhydride-treated wood. These experiments showed that wood modification is useful in understanding wood-adhesive interactions, in addition to determining how to develop adhesives for acetylated woods.

  19. Engineered Barrier System - Long-term Stability of Buffer and Backfill. Synthesis and extended abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Apted, Mick; Arthur, Randy [Monitor Scientific LLC, Denver, CO (United States); Savage, Dave [Quintessa Ltd., Nottingham (GB)] (eds.)

    2005-09-15

    SKI is preparing to review the license applications being developed by the Swedish Nuclear Fuel and Waste Management Company (SKB) for an encapsulation plant and a deep repository for the geological disposal of spent nuclear fuel. As part of its preparation, SKI is conducting a series of technical workshops on key aspects of the Engineered Barrier System (EBS) of the repository. This workshop concerns the longterm stability of the buffer and the backfill. Previous workshops have addressed the overall concept for long-term integrity of the EBS, the manufacturing, testing and QA of the EBS and the performance confirmation for the EBS. The goal of this work is to achieve a comprehensive overview of all aspects of SKB's EBS work prior to the handling of forthcoming license applications. The reports from the EBS workshops will be used as one important basis in future review work. The workshops involve the gathering of a sufficient number of independent experts in different subjects of relevance to the particular aspect of EBS. A workshop starts with presentations and discussions among these experts. Following this, SKB presents recent results and responds to questions as part of an informal hearing. Finally, the independent experts and the SKI staff examine the SKB responses from different viewpoints. This report aims to summarise the issues discussed at the buffer and backfill workshop and to extract the essential viewpoints that have been expressed. The report is not a comprehensive record of the discussions and individual statements made by workshop participants should be regarded as opinions rather than proven facts. This reports includes apart from the workshop synthesis, questions to SKB identified prior or during the workshop, and extended abstracts for introductory presentations.

  20. Engineered Barrier System - Long-term Stability of Buffer and Backfill. Synthesis and extended abstracts

    International Nuclear Information System (INIS)

    Apted, Mick; Arthur, Randy; Savage, Dave

    2005-09-01

    SKI is preparing to review the license applications being developed by the Swedish Nuclear Fuel and Waste Management Company (SKB) for an encapsulation plant and a deep repository for the geological disposal of spent nuclear fuel. As part of its preparation, SKI is conducting a series of technical workshops on key aspects of the Engineered Barrier System (EBS) of the repository. This workshop concerns the longterm stability of the buffer and the backfill. Previous workshops have addressed the overall concept for long-term integrity of the EBS, the manufacturing, testing and QA of the EBS and the performance confirmation for the EBS. The goal of this work is to achieve a comprehensive overview of all aspects of SKB's EBS work prior to the handling of forthcoming license applications. The reports from the EBS workshops will be used as one important basis in future review work. The workshops involve the gathering of a sufficient number of independent experts in different subjects of relevance to the particular aspect of EBS. A workshop starts with presentations and discussions among these experts. Following this, SKB presents recent results and responds to questions as part of an informal hearing. Finally, the independent experts and the SKI staff examine the SKB responses from different viewpoints. This report aims to summarise the issues discussed at the buffer and backfill workshop and to extract the essential viewpoints that have been expressed. The report is not a comprehensive record of the discussions and individual statements made by workshop participants should be regarded as opinions rather than proven facts. This reports includes apart from the workshop synthesis, questions to SKB identified prior or during the workshop, and extended abstracts for introductory presentations

  1. Advanced wood- and bio-composites : enhanced performance and sustainability

    Science.gov (United States)

    Jerrold E. Winandy

    2006-01-01

    Use of wood-based-composites technology to create value-added commodities and traditional construction materials is generally accepted worldwide. Engineered wood- and lignocellulosic-composite technologies allow users to add considerable value to a diverse number of wood- and lignocellulosic feedstocks including small-diameter timber, fast plantation-grown timber,...

  2. Cement bonded wood wool boards from podocarpus spp. for low ...

    African Journals Online (AJOL)

    ... sound insulation in walls, ceilings and floors, roofs, sound barriers and thermal insulation. Further research is required to investigate the use of different wood species and different mineral binders. Keywords: podocarpus spp, wood-wool, wood-cement composites. Journal of Civil Engineering Research and Practice Vol.

  3. Time-dependent stability of used engine oil degradation by cultures ...

    African Journals Online (AJOL)

    Pseudomonas fragi and Achromobacter aerogenes isolated from used engine oil polluted soils were grown in minimal salts medium (MSM) supplemented with used engine oil as sole carbon and energy source to evaluate their ability to biodegrade used engine oil. The two organisms utilized 73.3 and 80.0% of the oil with ...

  4. Design and Testing of a Pulsatile Conditioning System for Dynamic Endothelialization of Polyphenol-Stabilized Tissue Engineered Heart Valves.

    Science.gov (United States)

    Sierad, Leslie Neil; Simionescu, Agneta; Albers, Christopher; Chen, Joseph; Maivelett, Jordan; Tedder, Mary Elizabeth; Liao, Jun; Simionescu, Dan T

    2010-06-01

    Heart valve tissue engineering requires biocompatible and hemocompatible scaffolds that undergo remodeling and repopulation, but that also withstand harsh mechanical forces immediately following implantation. We hypothesized that reversibly stabilized acellular porcine valves, seeded with endothelial cells and conditioned in pulsatile bioreactors would pave the way for next generations of tissue engineered heart valves (TEHVs). A novel valve conditioning system was first designed, manufactured and tested to adequately assess TEHVs. The bioreactor created proper closing and opening of valves and allowed for multiple mounting methods in sterile conditions. Porcine aortic heart valve roots were decellularized by chemical extractions and treated with penta-galloyl glucose (PGG) for stabilization. Properties of the novel scaffolds were evaluated by testing resistance to collagenase and elastase, biaxial mechanical analysis, and thermal denaturation profiles. Porcine aortic endothelial cells were seeded onto the leaflets and whole aortic roots were mounted within the dynamic pulsatile heart valve bioreactor system under physiologic pulmonary valve pressures and analyzed after 17 days for cell viability, morphology, and metabolic activity. Our tissue preparation methods effectively removed cells, including the potent α-Gal antigen, while leaving a well preserved extra-cellular matrix scaffold with adequate mechanical properties. PGG enhanced stabilization of extracellular matrix components but also showed the ability to be reversible. Engineered valve scaffolds encouraged attachment and survival of endothelial cells for extended periods and showed signs of widespread cell coverage after conditioning. Our novel approach shows promise toward development of sturdy and durable TEHVs capable of remodeling and cellular repopulation.

  5. Significance of wood extractives for wood bonding.

    Science.gov (United States)

    Roffael, Edmone

    2016-02-01

    Wood contains primary extractives, which are present in all woods, and secondary extractives, which are confined in certain wood species. Extractives in wood play a major role in wood-bonding processes, as they can contribute to or determine the bonding relevant properties of wood such as acidity and wettability. Therefore, extractives play an immanent role in bonding of wood chips and wood fibres with common synthetic adhesives such as urea-formaldehyde-resins (UF-resins) and phenol-formaldehyde-resins (PF-resins). Extractives of high acidity accelerate the curing of acid curing UF-resins and decelerate bonding with alkaline hardening PF-resins. Water-soluble extractives like free sugars are detrimental for bonding of wood with cement. Polyphenolic extractives (tannins) can be used as a binder in the wood-based industry. Additionally, extractives in wood can react with formaldehyde and reduce the formaldehyde emission of wood-based panels. Moreover, some wood extractives are volatile organic compounds (VOC) and insofar also relevant to the emission of VOC from wood and wood-based panels.

  6. Finishes for Wood Decks

    Science.gov (United States)

    Mark Knaebe

    2013-01-01

    Wood decks have become an important part of residential construction. Wood decks can add versatile living space to a home and, with minimal maintenance, provide decades of use. However, wood decks are exposed to high levels of stress from severe weather conditions that shrink and swell the wood. Without proper maintenance, wood decks can develop problems such as checks...

  7. Radiographic testing of wood

    International Nuclear Information System (INIS)

    Osterloh, K.; Zscherpel, U.; Raedel, C.; Weidemann, G.; Meinel, D.; Goebbels, J.; Ewert, U.; Hasenstab, A.; Buecherl, T.

    2007-01-01

    Wood is an old and established consumption and construction material. It is still the most common material for constructing furniture, roofs, playgrounds and mine supports. In contrast to steel and concrete, wood warns of extreme loads by creaking. Its mechanical stability is more influenced by decay than by peripheral cracks. While external cracks are visible, internal decay by fungus growth is undetectable from outside. This may be a safety problem in supporting structures. The best analysis of the internal structure is provided by computed tomography, but this is also the most complex method, much more so than simple radiographic testing. However, the latter is made inaccurate by scattered radiation resulting from internal moisture. With the image processing options of digital radiographic techniques, the structural information can be separated effectively from noise. In contrast to X-ray and gamma radiography, neutron radiography provides information on the spatial distribution of moisture. In healthy wood, water is conducted in the sapwood while the hardwood is dry. Moisture in hardwood is caused by infestations, e.g. fungus growth. The contribution presents a comparative analysis of the available radiographic methods. (orig.)

  8. About the gasification of untreated scrap and waste wood in fluidized bed reactor for use in decentralized gas engine-cogeneration plants; Zur Vergasung von Rest- und Abfallholz in Wirbelschichtreaktoren fuer dezentrale Energieversorgungsanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Tepper, H.

    2005-10-20

    This dissertation examines the thermochemical conversion (gasification) of untreated scrap and waste wood in combustible gases for use in decentralized gas engine-cogeneration plants of low output (1 to 10 MW fuel power). A general section goes into the basics of the energetic utilization of solid biomass, the subprocesses of thermochemical conversion being described in more detail. Special attention is given to the processes and state of the art of biomass gasification in decentralized plants. A theoretical section analyzes the gasification models for solid biomass presented in the literature. Based on this analysis, a simplified kinetic model is derived for the gasification of untreated scrap and waste wood with air in bubbling fluidized bed reactors. It includes a fluid mechanic analysis of the fluidized bed based on HILLIGARDT, an empirical pyrolysis model and a global kinetic approach to the main chemical reaction taken from the literature. An experimental section describes the tests of the gasification of forest scrap wood in a semi-industrial fluidized bed gasification test plant with 150 kW fuel power and presents the significant test results. The gasification model derived is applied to check the test plant's standard settings and compare them with measured values. Furthermore, the model is employed to explain basic reaction paths and zones and to perform concluding parameter simulations. (orig.)

  9. Oil Uptake Percentage in Oil-Heat-Treated Wood, its Determination by Soxhlet Extraction, and its Effects on Wood Compression Strength Parallel to the Grain

    OpenAIRE

    Dali Cheng; Lijun Chen; Shenxue Jiang; Qisheng Zhang

    2013-01-01

    Oil heat treatment can effectively improve the dimensional stability and bio-durability of wood. However, the characteristics of high oil uptake (50 percent or higher) and high susceptibility to leaching from wood have an adverse effect on subsequent manufacturing processes of wood product and production costs. A solvent extraction (100% ethanol) process was used to extract the surplus oil from the treated wood. Because the making of powder specimens from high oil uptake wood would result in ...

  10. Engineering feasibility analysis for in-situ stabilization of Canonsburg residues. [UMTRA project

    Energy Technology Data Exchange (ETDEWEB)

    1982-01-01

    The US Department of Energy is considering several methods for carrying out remedial actions in Canonsburg, Pennsylvania, at the site of an inactive uranium-processing mill. The main objective of this study is to determine the feasibility of in-situ stabilization as the remedial action. In-situ stabilization is an alternative to site decontamination and offsite disposal. The problems associated with offsite hauling of large quantities of contaminated material and with the location and development of a new disposal site could be avoided by the implementation of an in-situ stabilization concept. In addition, the in-situ approach would be more cost-effective than offsite disposal. This study will establish that a technically feasible and implementable in-situ stabilization concept can be developed that meets regulatory requirements and is cost effective. This study in no way commits the DOE to implement any specific actions described herein. 11 refs., 30 figs., 24 tabs.

  11. Engineering feasibility analysis for in-situ stabilization of Canonsburg residues

    International Nuclear Information System (INIS)

    1982-01-01

    The US Department of Energy is considering several methods for carrying out remedial actions in Canonsburg, Pennsylvania, at the site of an inactive uranium-processing mill. The main objective of this study is to determine the feasibility of in-situ stabilization as the remedial action. In-situ stabilization is an alternative to site decontamination and offsite disposal. The problems associated with offsite hauling of large quantities of contaminated material and with the location and development of a new disposal site could be avoided by the implementation of an in-situ stabilization concept. In addition, the in-situ approach would be more cost-effective than offsite disposal. This study will establish that a technically feasible and implementable in-situ stabilization concept can be developed that meets regulatory requirements and is cost effective. This study in no way commits the DOE to implement any specific actions described herein. 11 refs., 30 figs., 24 tabs

  12. Choosing Wood Burning Appliances

    Science.gov (United States)

    Information to assist consumers in choosing a wood burning appliance, including types of appliances, the differences between certified and non-certified appliances, and alternative wood heating options.

  13. Improvements in processing characteristics and engineering properties of wood flour-filled high density polyethylene composite sheeting in the presence of hollow glass microspheres

    Science.gov (United States)

    Baris Yalcin; Steve E Amos; Andrew S D Souza; Craig M Clemons; I Sedat Gunes; Troy K Ista

    2012-01-01

    Hollow glass microspheres were introduced into wood flour/high density polyethylene composites by melt compounding in a twin-screw extruder. The prepared composites were subsequently converted to extruded profiles in order to obtain composite sheeting. The presence of hollow glass microspheres highly reduced the density of the extruded sheets down to 0.9 g/cc, while...

  14. Effects of Mixing Temperature and Wood Powder Size on Mechanical Properties of Wood Plastic Recycled Composite

    Science.gov (United States)

    Miki, Tsunehisa; Sugimoto, Hiroyuki; Kojiro, Keisuke; Kanayama, Kozo; Yamamoto, Ken

    In this study, wood (cedar) powder ranging from 53 µm to 1 mm sizes, recycled polypropylene (PP) / polyethylene (PE) and acid-modified PP as a compatibilization agent were used to produce a wood-plastic recycled composite (WPRC). For discussing the effects of the wood powder sizes on the mechanical properties of the WPRC, a mixing process of the wood powder and the plastics in a constant wood content of 50% weight was firstly performed by a mixing machine controlled temperature and rotation of mixing blade. And then, to obtain WPRC panels the wood and plastics mixtures were compressed in a mould under a constant pressure and a temperature for a certain holding time. WPRC specimens for mechanical tests were cut from the WPRC panels, and a tensile strength and a size-stability were acquired. The results show that the successful mixing process runs above 180°C, where the mixing torque required compounding keeps constant or slightly increases. The tensile strength of the WPRC increases when the smaller size of wood powder is used for wood/plastic compound under successful mixing conditions. It is shown from thickness change rate of specimens that mixing temperature of wood/plastic compound affects a size stability of the WPRC.

  15. Radioactive nuclear waste stabilization - Aspects of solid-state molecular engineering and applied geochemistry

    Science.gov (United States)

    Haggerty, S. E.

    1983-01-01

    Stabilization techniques for the storage of radioactive wastes are surveyed, with emphasis on immobilization in a primary barrier of synthetic rock. The composition, half-life, and thermal-emission characteristics of the wastes are shown to require thermally stable immobilization enduring at least 100,000 years. Glass materials are determined to be incapable of withstanding the expected conditions, average temperatures of 100-500 C for the first 100 years. The geological-time stability of crystalline materials, ceramics or synthetic rocks, is examined in detail by comparing their components with similar naturally occurring minerals, especially those containing the same radioactive elements. The high-temperature environment over the first 100 years is seen as stabilizing, since it can recrystallize radiation-induced metamicts. The synthetic-rock stabilization technique is found to be essentially feasible, and improvements are suggested, including the substitution of nepheline with freudenbergite and priderite for alkaline-waste stabilization, the maintenance of low oxygen fugacity, and the dilution of the synthetic-rock pellets into an inert medium.

  16. Improved stability and immunological potential of tetanus toxoid containing surface engineered bilosomes following oral administration.

    Science.gov (United States)

    Jain, Sanyog; Harde, Harshad; Indulkar, Anura; Agrawal, Ashish Kumar

    2014-02-01

    The present study was designed with the objective to investigate the stability and potential of glucomannan-modified bilosomes (GM-bilosomes) in eliciting immune response following oral administration. GM-bilosomes exhibited desired quality attributes simultaneously maintaining the chemical and conformation stability of the tetanus toxoid (TT) entrapped in to freeze dried formulations. The GM-bilosomes exhibited excellent stability in different simulated biological fluids and sustained release profile up to 24 h. GM-bilosomes elicited significantly higher (Ptetanus toxoid in the experiments. These GM-bilosomes not only elicited significantly higher systemic immune response as compared to bilosomes, niosomes and alum adsorbed orally administered TT, but also demonstrated mucosal immune response induction as well as cell mediated immune responses, which were not induced by the conventional route of immunization. © 2014.

  17. The role of curing period on the engineering characteristics of a cement-stabilized soil

    Directory of Open Access Journals (Sweden)

    Athanasopoulou Antonia

    2016-07-01

    Full Text Available Very often, pavements constructed in an economical manner or matching surface elevations of adjacent lanes cannot be designed for the soil conditions of the existing subgrade. Therefore, there is a need to stabilize the soil with an appropriate chemical substance in order to increase its strength to a satisfactory level. For the enhancement of subgrade soil strength characteristics, lime and cement are the most commonly used stabilizers. An experimental program was directed to the evaluation of a clayey soil and its mixtures with different cement contents performing tests on the index properties, the moisture-density relation, the unconfined compressive strength, and linear shrinkage. There is a definite improvement in strength. The time interval used to cure the prepared specimens affected positively both strength and plasticity features of the mixtures. A comparison with mixtures of the same soil with lime has been made, because of the wide use of lime in clay soil stabilization projects.

  18. Properties of Wood Fibre-Polypropylene Composites: Effect of Wood Fibre Source

    Science.gov (United States)

    Butylina, Svetlana; Martikka, Ossi; Kärki, Timo

    2011-04-01

    This study examined the effect of type of wood fibre source on the physical and mechanical properties of wood fibre-polypropylene composites. Wood flour, fibres of heat-treated wood and pellets were used as sources of wood fibres in the manufacturing process. All studied wood fibre-polypropylene composites were made from 75% wood, 22% recycled polypropylene (PP) and 3% maleated polypropylene (MAPP). Wood fibre-polypropylene composites were compounded in a conical twin-screw extruder. Water absorption and thickness swelling were studied. Mechanical properties of the composites were characterised by tensile, flexural, and impact testing. Micromechanical deformation processes were investigated using scanning electron microscopy done on the fractured surfaces of broken samples. The durability of composites exposed to three accelerated cycles of water immersion, freezing and thawing was examined. The results showed that the density of the composites was a key factor governing water absorption and thickness swelling. A significant improvement in tensile strength, flexural strength, and Charpy impact strength was observed for composites reinforced with heat-treated fibre compared to composites reinforced with pellets and especially to wood flour reinforced composites. The flexural strength and dimensional stability performance reduced after exposure to freeze-thaw cycling for all composites, but the degree of these changes was dependent on the wood fibre source.

  19. Durability of wood plastic composites manufactured from recycled plastic

    Directory of Open Access Journals (Sweden)

    Irina Turku

    2018-03-01

    Full Text Available The influence of accelerated weathering, xenon-arc light and freeze-thaw cycling on wood plastic composites extruded from a recycled plastic was studied. The results showed that, in general, weathering had a stronger impact on samples made from plastic waste compared to a sample made from virgin material. After weathering, the mechanical properties, tensile and flexural, were reduced by 2–30%, depending on the plastic source. Wettability of the samples was shown to play a significant role in their stability. Chemical analysis with infrared spectroscopy and surface observation with a scan electron microscope confirmed the mechanical test results. Incorporation of carbon black retained the properties during weathering, reducing the wettability of the sample, diminishing the change of mechanical properties, and improving color stability. Keywords: Environmental science, Mechanical engineering, Materials science

  20. Recovery of Metals and Stabilization of Arsenic from (Bio-)Leaching Operations by Engineered Biological Processes

    NARCIS (Netherlands)

    Gonzalez Contreras, P.A.; weghuis, M.O.; Weijma, J.; Buisman, C.J.N.

    2013-01-01

    This paper focuses on the application of biotechnological stabilization of arsenic from (bio-) leaching operations. One of the latest applications of the Thioteq technology is arsenic immobilization. The Thioteq-scorodite biorecovery reactor is an aerobic system to immobilise arsenic in

  1. ONSITE ENGINEERING REPORT FOR SOLIDIFICATION/ STABILIZATION TREATMENT TESTING OF CONTAMINATED SOILS

    Science.gov (United States)

    The EPA's Office of Solid Waste and Emergency Response (OSWER) is currently developing land disposal restrictions (LDRs) for contaminated soil and debris (CS&D). The Office of Research and Development, through its Risk Reduction Engineering Laboratory (RREL), is providing support...

  2. The Potential of Genetic Engineering in Agriculture to Affect Global Stability

    Science.gov (United States)

    2013-04-17

    on world hunger. Agribusiness conglomerates seeking to increase profit margins are 2 proselytizing genetic engineering as a necessary...ethanol gas to turn them red. Agribusiness took particular notice. 13 Calgene was able to 4 isolate the gene that caused a tomato to ripen and...normally fed on them followed.16 The increasing connectivity of national economies through globalization has allowed multinational agribusiness

  3. Application of Used Engine Oil in Soil-Cement Stabilization | Obeta ...

    African Journals Online (AJOL)

    A lot of studies has shown that the addition of oils to some soils at 3% and 6% contaminations by dry weight resulted in an increase in the unsoaked California bearing ratio (CBR) of the soil. This paper presents the result of investigating the applicability of used engine oil at 3% contamination as a means of reuse in the ...

  4. Internal oscillating current-sustained RF plasmas: Parameters, stability, and potential for surface engineering

    DEFF Research Database (Denmark)

    Ostrikov, K.; Tsakadze, E.L.; Tsakadze, Z.L.

    2005-01-01

    A new source of low-frequency (0.46 MHz) inductively coupled plasmas sustained by the internal planar "unidirectional" RF current driven through a specially designed internal antenna configuration has been developed. The experimental results of the investigation of the optical and global argon pl...... applications and surface engineering. (c) 2005 Elsevier B.V. All rights reserved....

  5. Effect of electrolyte valency, alginate concentration and pH on engineered TiO₂ nanoparticle stability in aqueous solution.

    Science.gov (United States)

    Loosli, Frédéric; Le Coustumer, Philippe; Stoll, Serge

    2015-12-01

    Agglomeration and disagglomeration processes are expected to play a key role on the fate of engineered nanoparticles in natural aquatic systems. These processes are investigated here in detail by studying first the stability of TiO2 nanoparticles in the presence of monovalent and divalent electrolytes at different pHs (below and above the point of zero charge of TiO2) and discussing the importance of specific divalent cation adsorption with the help of the DLVO theory as well as the importance of the nature of the counterions. Then the impact of one polysaccharide (alginate) on the stability of agglomerates formed under pH and water hardness representative of Lake Geneva environmental conditions is investigated. In these conditions the large TiO2 agglomerates (diameter>1μm) are positively charged due to Ca(2+) and Mg(2+) specific adsorption and alginate, which is negatively charged, adsorbs onto the agglomerate surface. Our results indicate that the presence of alginate at typical natural organic matter concentration (1-10 mg L(-1)) strongly modifies the TiO2 agglomerate (50 mg L(-1)) stability by inducing their partial and rapid disagglomeration. The importance of disagglomeration is found dependent on the alginate concentration with maximum of disagglomeration obtained for alginate concentration ≥8 mg L(-1) and leading to 400 nm fragments. From an environmental point of view partial restabilization of TiO2 agglomerates in the presence of alginate constitutes an important outcome. Disagglomeration will enhance their transport and residence time in aquatic systems which is an important step in the current knowledge on risk assessment associated to engineered nanoparticles. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Local Stability Analysis of a Thermo-Economic Model of a Chambadal-Novikov-Curzon-Ahlborn Heat Engine

    Directory of Open Access Journals (Sweden)

    Lev Guzmán-Vargas

    2011-08-01

    Full Text Available In this work we present a local stability analysis of the thermo-economic model of an irreversible heat engine working at maximum power conditions. The thermo-economic model is based on the maximization of a benefit function which is defined by the ratio of the power output and the total cost involved in the plant’s performance. Our study shows that, after a small perturbation, the system decays exponentially to the steady state determined by two different relaxation times. In particular, we show that the relaxation times are function of the temperature ratio τ = T2/T1 (T1 > T2, the cost function ƒ and the parameter R (a parameter related to the degree of internal irreversibilities. We observe that the stability of the system improves as τ increases whereas for changes in ƒ and R, the stability properties are characterized by a rapid decay along the fast eigendirection as ƒ increases and R decreases. Finally, we discuss our results in the context of energetic properties.

  7. Wood Species Recognition System

    OpenAIRE

    Bremananth R; Nithya B; Saipriya R

    2009-01-01

    The proposed system identifies the species of the wood using the textural features present in its barks. Each species of a wood has its own unique patterns in its bark, which enabled the proposed system to identify it accurately. Automatic wood recognition system has not yet been well established mainly due to lack of research in this area and the difficulty in obtaining the wood database. In our work, a wood recognition system has been designed based on pre-processing te...

  8. Engineering bright solitons to enhance the stability of two-component Bose-Einstein condensates

    Science.gov (United States)

    Radha, R.; Vinayagam, P. S.; Sudharsan, J. B.; Liu, Wu-Ming; Malomed, Boris A.

    2015-12-01

    We consider a system of coupled Gross-Pitaevskii (GP) equations describing a binary quasi-one-dimensional Bose-Einstein condensate (BEC) with intrinsic time-dependent attractive interactions, placed in a time-dependent expulsive parabolic potential, in a special case when the system is integrable (a deformed Manakov's system). Since the nonlinearity in the integrable system which represents binary attractive interactions exponentially decays with time, solitons are also subject to decay. Nevertheless, it is shown that the robustness of bright solitons can be enhanced in this system, making their respective lifetime longer, by matching the time dependence of the interaction strength (adjusted with the help of the Feshbach-resonance management) to the time modulation of the strength of the parabolic potential. The analytical results, and their stability, are corroborated by numerical simulations. In particular, we demonstrate that the addition of random noise does not impact the stability of the solitons.

  9. Wood mimetic hydrogel beads for enzyme immobilization.

    Science.gov (United States)

    Park, Saerom; Kim, Sung Hee; Won, Keehoon; Choi, Joon Weon; Kim, Yong Hwan; Kim, Hyung Joo; Yang, Yung-Hun; Lee, Sang Hyun

    2015-01-22

    Wood component-based composite hydrogels have potential applications in biomedical fields owing to their low cost, biodegradability, and biocompatibility. The controllable properties of wood mimetic composites containing three major wood components are useful for enzyme immobilization. Here, lipase from Candida rugosa was entrapped in wood mimetic beads containing cellulose, xylan, and lignin by dissolving wood components with lipase in [Emim][Ac], followed by reconstitution. Lipase entrapped in cellulose/xylan/lignin beads in a 5:3:2 ratio showed the highest activity; this ratio is very similar to that in natural wood. The lipase entrapped in various wood mimetic beads showed increased thermal and pH stability. The half-life times of lipase entrapped in cellulose/alkali lignin hydrogel were 31- and 82-times higher than those of free lipase during incubation under denaturing conditions of high temperature and low pH, respectively. Owing to their biocompatibility, biodegradability, and controllable properties, wood mimetic hydrogel beads can be used to immobilize various enzymes for applications in the biomedical, bioelectronic, and biocatalytic fields. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Exploring the metabolic stability of engineered hairy roots after 16 years maintenance

    Directory of Open Access Journals (Sweden)

    Suvi Tuulikki Häkkinen

    2016-09-01

    Full Text Available Plants remain a major source of new drugs, leads and fine chemicals. Cell cultures deriving from plants offer a fascinating tool to study plant metabolic pathways and offer large scale production systems for valuable compounds – commercial examples include compounds such as paclitaxel. The major constraint with undifferentiated cell cultures is that they are generally considered to be genetically unstable and cultured cells tend to produce low yields of secondary metabolites especially over time. Hairy roots, a tumour tissue caused by infection of Agrobacterium rhizogenes is a relevant alternative for plant secondary metabolite production for being fast growing, able to grow without phytohormones, and displaying higher stability than undifferentiated cells. Although genetic and metabolic stability has often been connected to transgenic hairy roots, there are only few reports on how a very long-term subculturing effects on the production capacity of hairy roots. In this study, hairy roots producing high tropane alkaloid levels were subjected to 16 -year follow-up in relation to genetic and metabolic stability. Cryopreservation method for hairy roots of H. muticus was developed to replace laborious subculturing, and although the post-thaw recovery rates remained low, the expression of transgene remained unaltered in cryopreserved roots. It was shown that although displaying some fluctuation in the metabolite yields, even an exceedingly long-term subculturing was successfully applied without significant loss of metabolic activity.

  11. Engineering bright solitons to enhance the stability of two-component Bose–Einstein condensates

    Energy Technology Data Exchange (ETDEWEB)

    Radha, R., E-mail: radha_ramaswamy@yahoo.com [Centre for Nonlinear Science, PG and Research Dept. of Physics, Govt. College for Women (Autonomous), Kumbakonam 612001 (India); Vinayagam, P.S.; Sudharsan, J.B. [Centre for Nonlinear Science, PG and Research Dept. of Physics, Govt. College for Women (Autonomous), Kumbakonam 612001 (India); Liu, Wu-Ming, E-mail: wmliu@iphy.ac.cn [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing-100190 (China); Malomed, Boris A., E-mail: malomed@post.tau.ac.il [Department of Physical Electronics, School of Electrical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978 (Israel)

    2015-12-04

    We consider a system of coupled Gross–Pitaevskii (GP) equations describing a binary quasi-one-dimensional Bose–Einstein condensate (BEC) with intrinsic time-dependent attractive interactions, placed in a time-dependent expulsive parabolic potential, in a special case when the system is integrable (a deformed Manakov's system). Since the nonlinearity in the integrable system which represents binary attractive interactions exponentially decays with time, solitons are also subject to decay. Nevertheless, it is shown that the robustness of bright solitons can be enhanced in this system, making their respective lifetime longer, by matching the time dependence of the interaction strength (adjusted with the help of the Feshbach-resonance management) to the time modulation of the strength of the parabolic potential. The analytical results, and their stability, are corroborated by numerical simulations. In particular, we demonstrate that the addition of random noise does not impact the stability of the solitons. - Highlights: • We formulate a versatile mechanism to enhance the lifetime of vectorial condensates employing Feshbach Resonance. • Vectorial condensates in a transient harmonic trap are more long lived compared to their counterpart in a time independent harmonic trap. • Corroborate the exact analytical results with numerical simulations. • Addition of random noise does not impact the stability of vector BECs.

  12. Engineering bright solitons to enhance the stability of two-component Bose–Einstein condensates

    International Nuclear Information System (INIS)

    Radha, R.; Vinayagam, P.S.; Sudharsan, J.B.; Liu, Wu-Ming; Malomed, Boris A.

    2015-01-01

    We consider a system of coupled Gross–Pitaevskii (GP) equations describing a binary quasi-one-dimensional Bose–Einstein condensate (BEC) with intrinsic time-dependent attractive interactions, placed in a time-dependent expulsive parabolic potential, in a special case when the system is integrable (a deformed Manakov's system). Since the nonlinearity in the integrable system which represents binary attractive interactions exponentially decays with time, solitons are also subject to decay. Nevertheless, it is shown that the robustness of bright solitons can be enhanced in this system, making their respective lifetime longer, by matching the time dependence of the interaction strength (adjusted with the help of the Feshbach-resonance management) to the time modulation of the strength of the parabolic potential. The analytical results, and their stability, are corroborated by numerical simulations. In particular, we demonstrate that the addition of random noise does not impact the stability of the solitons. - Highlights: • We formulate a versatile mechanism to enhance the lifetime of vectorial condensates employing Feshbach Resonance. • Vectorial condensates in a transient harmonic trap are more long lived compared to their counterpart in a time independent harmonic trap. • Corroborate the exact analytical results with numerical simulations. • Addition of random noise does not impact the stability of vector BECs.

  13. Stabilizing a Bell state of two superconducting qubits by dissipation engineering

    Science.gov (United States)

    Leghtas, Z.; Vool, U.; Shankar, S.; Hatridge, M.; Girvin, S. M.; Devoret, M. H.; Mirrahimi, M.

    2013-08-01

    We propose a dissipation-engineering scheme that prepares and protects a maximally entangled state of a pair of superconducting qubits. This is done by off-resonantly coupling the two qubits to a low-Q cavity mode playing the role of a dissipative reservoir. We engineer this coupling by applying six continuous-wave microwave drives with appropriate frequencies. The two qubits need not be identical. We show that our approach does not require any fine-tuning of the parameters and requires only that certain ratios between them be large. With currently achievable coherence times, simulations indicate that a Bell state can be maintained over arbitrary long times with fidelities above 94%. Such performance leads to a significant violation of Bell's inequality (Clauser-Horne-Shimony-Holt correlation larger than 2.6) for arbitrary long times.

  14. Combined analytical and numerical approaches in Dynamic Stability analyses of engineering system

    Czech Academy of Sciences Publication Activity Database

    Náprstek, Jiří

    2015-01-01

    Roč. 338, March (2015), s. 2-41 ISSN 0022-460X R&D Projects: GA ČR(CZ) GC13-34405J Institutional support: RVO:68378297 Keywords : strongly nonlinear oscillators * moment Lyapunov exponents * predator-prey system * differential-equations Subject RIV: JM - Building Engineering Impact factor: 2.107, year: 2015 http://www.sciencedirect.com/science/article/pii/S0022460X14005355

  15. WGDB: Wood Gene Database with search interface.

    Science.gov (United States)

    Goyal, Neha; Ginwal, H S

    2014-01-01

    Wood quality can be defined in terms of particular end use with the involvement of several traits. Over the last fifteen years researchers have assessed the wood quality traits in forest trees. The wood quality was categorized as: cell wall biochemical traits, fibre properties include the microfibril angle, density and stiffness in loblolly pine [1]. The user friendly and an open-access database has been developed named Wood Gene Database (WGDB) for describing the wood genes along the information of protein and published research articles. It contains 720 wood genes from species namely Pinus, Deodar, fast growing trees namely Poplar, Eucalyptus. WGDB designed to encompass the majority of publicly accessible genes codes for cellulose, hemicellulose and lignin in tree species which are responsive to wood formation and quality. It is an interactive platform for collecting, managing and searching the specific wood genes; it also enables the data mining relate to the genomic information specifically in Arabidopsis thaliana, Populus trichocarpa, Eucalyptus grandis, Pinus taeda, Pinus radiata, Cedrus deodara, Cedrus atlantica. For user convenience, this database is cross linked with public databases namely NCBI, EMBL & Dendrome with the search engine Google for making it more informative and provides bioinformatics tools named BLAST,COBALT. The database is freely available on www.wgdb.in.

  16. Engineering a highly active thermophilic β-glucosidase to enhance its pH stability and saccharification performance.

    Science.gov (United States)

    Xia, Wei; Xu, Xinxin; Qian, Lichun; Shi, Pengjun; Bai, Yingguo; Luo, Huiying; Ma, Rui; Yao, Bin

    2016-01-01

    β-Glucosidase is an important member of the biomass-degrading enzyme system, and plays vital roles in enzymatic saccharification for biofuels production. Candidates with high activity and great stability over high temperature and varied pHs are always preferred in industrial practice. To achieve cost-effective biomass conversion, exploring natural enzymes, developing high level expression systems and engineering superior mutants are effective approaches commonly used. A newly identified β-glucosidase of GH3, Bgl3A, from Talaromyces leycettanus JCM12802, was overexpressed in yeast strain Pichia pastoris GS115, yielding a crude enzyme activity of 6000 U/ml in a 3 L fermentation tank. The purified enzyme exhibited outstanding enzymatic properties, including favorable temperature and pH optima (75 °C and pH 4.5), good thermostability (maintaining stable at 60 °C), and high catalytic performance (with a specific activity and catalytic efficiency of 905 U/mg and 9096/s/mM on pNPG, respectively). However, the narrow stability of Bgl3A at pH 4.0-5.0 would limit its industrial applications. Further site-directed mutagenesis indicated the role of excessive O-glycosylation in pH liability. By removing the potential O-glycosylation sites, two mutants showed improved pH stability over a broader pH range (3.0-10.0). Besides, with better stability under pH 5.0 and 50 °C compared with wild type Bgl3A, saccharification efficiency of mutant M1 was improved substantially cooperating with cellulase Celluclast 1.5L. And mutant M1 reached approximately equivalent saccharification performance to commercial β-glucosidase Novozyme 188 with identical β-glucosidase activity, suggesting its great prospect in biofuels production. In this study, we overexpressed a novel β-glucosidase Bgl3A with high specific activity and high catalytic efficiency in P. pastoris. We further proved the negative effect of excessive O-glycosylation on the pH stability of Bgl3A, and enhanced the p

  17. Functional stability of endothelial cells on a novel hybrid scaffold for vascular tissue engineering

    International Nuclear Information System (INIS)

    Pankajakshan, Divya; Krishnan, Lissy K; Krishnan V, Kalliyana

    2010-01-01

    Porous and pliable conduits made of biodegradable polymeric scaffolds offer great potential for the development of blood vessel substitutes but they generally lack signals for cell proliferation, survival and maintenance of a normal phenotype. In this study we have prepared and evaluated porous poly(ε-caprolactone) (PCL) integrated with fibrin composite (FC) to get a biomimetic hybrid scaffold (FC PCL) with the biological properties of fibrin, fibronectin (FN), gelatin, growth factors and glycosaminoglycans. Reduced platelet adhesion on a human umbilical vein endothelial cell-seeded hybrid scaffold as compared to bare PCL or FC PCL was observed, which suggests the non-thrombogenic nature of the tissue-engineered scaffold. Analysis of real-time polymerase chain reaction (RT-PCR) after 5 days of endothelial cell (EC) culture on a hybrid scaffold indicated that the prothrombotic von Willebrand factor and plasminogen activator inhibitor (PAI) were quiescent and stable. Meanwhile, dynamic expressions of tissue plasminogen activator (tPA) and endothelial nitric oxide synthase indicated the desired cell phenotype on the scaffold. On the hybrid scaffold, shear stress could induce enhanced nitric oxide release, which implicates vaso-responsiveness of EC grown on the tissue-engineered construct. Significant upregulation of mRNA for extracellular matrix (ECM) proteins, collagen IV and elastin, in EC was detected by RT-PCR after growing them on the hybrid scaffold and FC-coated tissue culture polystyrene (FC TCPS) but not on FN-coated TCPS. The results indicate that the FC PCL hybrid scaffold can accomplish a remodeled ECM and non-thrombogenic EC phenotype, and can be further investigated as a scaffold for cardiovascular tissue engineering. (communication)

  18. Assessment of engineering plant analyzer with Peach Bottom 2 stability tests

    International Nuclear Information System (INIS)

    Rohatgi, U.S.; Mallen, A.N.; Cheng, H.S.; Wulff, W.

    1992-01-01

    Engineering Plant Analyzer (EPA) has been developed to simulate plant transients for Boiling Water Reactor (BWR). Recently, this code has been used to simulate LaSalle-2 instability event which was initiated by a failure in the feed water heater. The simulation was performed for the scram conditions and for the postulated failure in the scram. In order to assess the capability of the EPA to simulate oscillatory flows as observed in the LaSalle event, EPA has been benchmarked with the available data from the Peach Bottom 2 (PB2) Instability tests PT1, PT2, and PT4. This document provides a description of these tests

  19. Life-cycle environmental performance of renewable building materials in the context of residential construction : phase II research report : an extension to the 2005 phase I research report. Module N, Life-cycle inventory of manufacturing prefinished engineered wood flooring in the eastern United States

    Science.gov (United States)

    Richard D. Bergman; Scott A. Bowe

    2011-01-01

    This study summarizes the environmental performance of prefinished engineered wood flooring using life-cycle inventory (LCI) analysis. Using primary mill data gathered from manufacturers in the eastern United States and applying the methods found in Consortium for Research on Renewable Industrial Materials (CORRIM) Research Guidelines and International Organization of...

  20. A quality evaluation of stabilization of rotation frequency of gas-diesel engines when using an adaptive automatic control system

    Science.gov (United States)

    Zhilenkov, A. A.; Efremov, A. A.

    2017-02-01

    A possibility of quality improvement of stabilization of rotation frequency of the gas-diesels used as prime mover of generator set in the multigenerator units working for abruptly variable load of large power is considered. An evaluation is made on the condition of fuzzy controller use developed and described by the authors in a number of articles. An evaluation has shown that theoretically, the revolution range of a gas-diesel engine may be reduced 25-30 times in case of optimal settings of the controller in the whole power range. The results of modelling showing a considerable quality improvement of transient processes in the investigated system during a sharp change of loading are presented in this article.

  1. Wood products used in the construction of low-rise nonresidential buildings in the United States, 2008

    Science.gov (United States)

    David McKeever

    2010-01-01

    Low-rise nonresidential building construction is an important market for lumber, structural wood panels, nonstructural wood panels, and engineered wood products in the United States. This report examines low-rise nonresidential buildings of four or fewer stories only. Buildings with five or more stories are normally severely restricted by building code from being wood...

  2. Topology Engineering of Proteins in Vivo Using Genetically Encoded, Mechanically Interlocking SpyX Modules for Enhanced Stability.

    Science.gov (United States)

    Liu, Dong; Wu, Wen-Hao; Liu, Ya-Jie; Wu, Xia-Ling; Cao, Yang; Song, Bo; Li, Xiaopeng; Zhang, Wen-Bin

    2017-05-24

    Recombinant proteins are traditionally limited to linear configuration. Herein, we report in vivo protein topology engineering using highly efficient, mechanically interlocking SpyX modules named AXB and BXA. SpyX modules are protein domains composed of p53dim (X), SpyTag (A), and SpyCatcher (B). The p53dim guides the intertwining of the two nascent protein chains followed by autocatalytic isopeptide bond formation between SpyTag and SpyCatcher to fulfill the interlocking, leading to a variety of backbone topologies. Direct expression of AXB or BXA produces protein catenanes with distinct ring sizes. Recombinant proteins containing SpyX modules are obtained either as mechanically interlocked obligate dimers if the protein of interest is fused to the N- or C-terminus of SpyX modules, or as star proteins if the protein is fused to both N- and C-termini. As examples, cellular syntheses of dimers of (GB1) 2 (where GB1 stands for immunoglobulin-binding domain B1 of streptococcal protein G) and of four-arm elastin-like star proteins were demonstrated. Comparison of the catenation efficiencies in different constructs reveals that BXA is generally much more effective than AXB, which is rationalized by the arrangement of three domains in space. Mechanical interlocking induces considerable stability enhancement. Both AXB and BXA have a melting point ∼20 °C higher than the linear controls and the BXA catenane has a melting point ~2 °C higher than the cyclic control BX'A. Notably, four-arm elastin-like star proteins demonstrate remarkable tolerance against trypsin digestion. The SpyX modules provide a convenient and versatile approach to construct unconventional protein topologies via the "assembly-reaction" synergy, which opens a new horizon in protein science for stability enhancement and function reinforcement via topology engineering.

  3. A chemometric investigation of aromatic emission profiles from a marine engine in comparison with residential wood combustion and road traffic: Implications for source apportionment inside and outside sulphur emission control areas

    Science.gov (United States)

    Czech, Hendryk; Stengel, Benjamin; Adam, Thomas; Sklorz, Martin; Streibel, Thorsten; Zimmermann, Ralf

    2017-10-01

    Ship emissions are known to cause severe impacts on human health, but are less restricted than land-based emissions. A regulation to improve air quality in coastal regions and frequented waterways is the limitation of fuel sulphur content to 0.1% in sulphur emission control areas (SECAs), which has caused a switch from heavy fuel oil (HFO) towards diesel-like marine gas oil (MGO) or marine diesel oil (MDO). The fraction of aromatic organic vapours in the exhaust from a marine engine, operating on HFO and MGO, was investigated by resonance-enhanced multi-photon ionisation time-of-flight mass spectrometry (REMPI-TOFMS). MGO with fuel sulphur content (FSC) below 0.1% and HFO with an average FSC of 2.7% denote representative marine fuels inside and outside SECAs, respectively. The obtained emission spectra were combined with data of previous REMPI-TOFMS studies of combustion engines and wood combustion in statistical analyses to derive marker substances for ship emissions inside and outside SECAs. A diagnostic ratio of C2-naphthalenes to methyl-naphthalenes was found to hold for a good discriminator between ship emissions on the one hand and road traffic and wood combustion on the other hand. Furthermore, random REMPI spectra from all emission sources were mixed with different proportions in a simulation to create a model based on partial least square (PLS) regression for the prediction of ship contribution to aromatic organic vapours. We point out that in particular PAHs with higher degree of alkylation are significant markers for primary ship emissions which may support source apportionment studies inside and outside SECAs to assess the benefits of fuel sulphur content regulation on air quality.

  4. The use of urban wood waste as an energy resource

    Science.gov (United States)

    Khudyakova, G. I.; Danilova, D. A.; Khasanov, R. R.

    2017-06-01

    The capabilities use of wood waste in the Ekaterinburg city, generated during the felling of trees and sanitation in the care of green plantations in the streets, parks, squares, forest parks was investigated in this study. In the cities at the moment, all the wood, that is removed from city streets turns into waste completely. Wood waste is brought to the landfill of solid household waste, and moreover sorting and evaluation of the quantitative composition of wood waste is not carried out. Several technical solutions that are used in different countries have been proposed for the energy use of wood waste: heat and electrical energy generation, liquid and solid biofuel production. An estimation of the energy potential of the city wood waste was made, for total and for produced heat and electrical energy based on modern engineering developments. According to our estimates total energy potential of wood waste in the city measure up more 340 thousand GJ per year.

  5. Remarkable alkaline stability of an engineered protein A as immunoglobulin affinity ligand: C domain having only one amino acid substitution

    Science.gov (United States)

    Minakuchi, Kazunobu; Murata, Dai; Okubo, Yuji; Nakano, Yoshiyuki; Yoshida, Shinichi

    2013-01-01

    Protein A affinity chromatography is the standard purification process for the capture of therapeutic antibodies. The individual IgG-binding domains of protein A (E, D, A, B, C) have highly homologous amino acid sequences. From a previous report, it has been assumed that the C domain has superior resistance to alkaline conditions compared to the other domains. We investigated several properties of the C domain as an IgG-Fc capture ligand. Based on cleavage site analysis of a recombinant protein A using a protein sequencer, the C domain was found to be the only domain to have neither of the potential alkaline cleavage sites. Circular dichroism (CD) analysis also indicated that the C domain has good physicochemical stability. Additionally, we evaluated the amino acid substitutions at the Gly-29 position of the C domain, as the Z domain (an artificial B domain) acquired alkaline resistance through a G29A mutation. The G29A mutation proved to increase the alkaline resistance of the C domain, based on BIACORE analysis, although the improvement was significantly smaller than that observed for the B domain. Interestingly, a number of other amino acid mutations at the same position increased alkaline resistance more than did the G29A mutation. This result supports the notion that even a single mutation on the originally alkali-stable C domain would improve its alkaline stability. An engineered protein A based on this C domain is expected to show remarkable performance as an affinity ligand for immunoglobulin. PMID:23868198

  6. Towards the regulation of aerosol emissions by their potential health impact: Assessing adverse effects of aerosols from wood combustion and ship diesel engine emissions by combining comprehensive data on the chemical composition and their toxicological effects on human lung cells

    Science.gov (United States)

    Zimmermann, R.; Streibel, T.; Dittmar, G.; Kanashova, T.; Buters, J.; Öder, S.; Paur, H. R.; Dilger, M.; Weiss, C.; Harndorf, H.; Stengel, B.; Hirvonen, M. R.; Jokiniemi, J.; Hiller, K.; Sapcariu, S.; Sippula, O.; Orasche, J.; Müller, L.; Rheda, A.; Passig, J.; Radischat, C.; Czech, H.; Tiita, P.; Jalava, P.; Kasurinen, S.; Schwemer, T.; Yli-Prilä, P.; Tissari, J.; Lamberg, H.; Schnelle-Kreis, J.

    2014-12-01

    Ship engine emissions are important regarding lung and cardiovascular diseases in coastal regions worldwide. Bio mass burning is made responsible for adverse health effects in many cities and rural regions. The Virtual Helmholtz Institute-HICE (www.hice-vi.eu) addresses chemical & physical properties and health effects of anthropogenic combustion emissions. Typical lung cell responses to combustion aerosols include inflammation and apoptosis, but a molecular link with the specific chemical composition in particular of ship emissions has not been established. Through an air-liquid interface exposure system (ALI), we exposed human lung cells at-site to exhaust fumes from a ship engine running on common heavy fuel oil (HFO) and cleaner-burning diesel fuel (DF) as well as to emissions of wood combustion compliances. A special field deployable ALI-exposition system and a mobile S2-biological laboratory were developed for this study. Human alveolar basal epithelial cells (A549 etc.) are ALI-exposed to fresh, diluted (1:40-1:100) combustion aerosols and subsequently were toxicologically and molecular-biologically characterized. Advanced chemical analyses of the exhaust aerosols were combined with transcriptional, proteomic and metabolomic profiling to characterise the cellular responses. The HFO ship emissions contained high concentrations of toxic compounds (transition metals, organic toxicants) and particle masses. The cellular responses included inflammation and oxidative stress. Surprisingly, the DF ship emissions, which predominantly contain rather "pure" carbonaceous soot and much less known toxicants, induced significantly broader biological effects, affecting essential cellular pathways (e.g., mitochondrial function and intracellular transport). Therefore the use of distillate fuels for shipping (this is the current emission reduction strategy of the IMO) appears insufficient for diminishing health effects. The study suggests rather reducing the particle emissions

  7. Unsteady flowfield in an integrated rocket ramjet engine and combustion dynamics of a gas turbine swirl-stabilized injector

    Science.gov (United States)

    Sung, Hong-Gye

    This research focuses on the time-accurate simulation and analysis of the unsteady flowfield in an integrated rocket-ramjet engine (IRR) and combustion dynamics of a swirl-stabilized gas turbine engine. The primary objectives are: (1) to establish a unified computational framework for studying unsteady flow and flame dynamics in ramjet propulsion systems and gas turbine combustion chambers, and (2) to investigate the parameters and mechanisms responsible for driving flow oscillations. The first part of the thesis deals with a complete axi-symmetric IRR engine. The domain of concern includes a supersonic inlet diffuser, a combustion chamber, and an exhaust nozzle. This study focused on the physical mechanism of the interaction between the oscillatory terminal shock in the inlet diffuser and the flame in the combustion chamber. In addition, the flow and ignition transitions from the booster to the sustainer phase were analyzed comprehensively. Even though the coupling between the inlet dynamics and the unsteady motions of flame shows that they are closely correlated, fortunately, those couplings are out of phase with a phase lag of 90 degrees, which compensates for the amplification of the pressure fluctuation in the inlet. The second part of the thesis treats the combustion dynamics of a lean-premixed gas turbine swirl injector. A three-dimensional computation method utilizing the message passing interface (MPI) Parallel architecture and large-eddy-simulation technique was applied. Vortex breakdown in the swirling flow is clearly visualized and explained on theoretical bases. The unsteady turbulent flame dynamics are carefully simulated so that the flow motion can be characterized in detail. It was observed that some fuel lumps escape from the primary combustion zone, and move downstream and consequently produce hot spots and large vortical structures in the azimuthal direction. The correlation between pressure oscillation and unsteady heat release is examined by

  8. Characterization and potential recycling of home building wood waste

    Science.gov (United States)

    Philip A. Araman; D.P. Hindman; M.F. Winn

    2010-01-01

    Construction waste represents a significant portion of landfill waste, estimated as 17% of the total waste stream. Wood construction waste of a 2000 square foot single family home we found to be 1500-3700 lbs of solid-sawn wood, and 1000-1800 lbs of engineered wood products (EWP). Much of the solid-sawn lumber and EWPs could be recycled into several products. Through a...

  9. Wood's lamp examination

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003386.htm Wood lamp examination To use the sharing features on this page, please enable JavaScript. A Wood lamp examination is a test that uses ultraviolet ( ...

  10. Wood's lamp illumination (image)

    Science.gov (United States)

    A Wood's lamp emits ultraviolet light and can be a diagnostic aid in determining if someone has a fungal ... is an infection on the area where the Wood's lamp is illuminating, the area will fluoresce. Normally ...

  11. Wood-plastic combination

    International Nuclear Information System (INIS)

    Schaudy, R.

    1978-02-01

    A review on wood-plastic combinations is given including the production (wood and plastic component, radiation hardening, curing), the obtained properties, present applications and prospects for the future of these materials. (author)

  12. Mechanics of Wood Machining

    CERN Document Server

    Csanády, Etele

    2013-01-01

    Wood is one of the most valuable materials for mankind, and since our earliest days wood materials have been widely used. Today we have modern woodworking machine and tools; however, the raw wood materials available are continuously declining. Therefore we are forced to use this precious material more economically, reducing waste wherever possible. This new textbook on the “Mechanics of Wood Machining” combines the quantitative, mathematical analysis of the mechanisms of wood processing with practical recommendations and solutions. Bringing together materials from many sources, the book contains new theoretical and experimental approaches and offers a clear and systematic overview of the theory of wood cutting, thermal loading in wood-cutting tools, dynamic behaviour of tool and work piece, optimum choice of operational parameters and energy consumption, the wear process of the tools, and the general regularities of wood surface roughness. Diagrams are provided for the quick estimation of various process ...

  13. Solvolytic liquefaction of wood under mild conditions

    Energy Technology Data Exchange (ETDEWEB)

    Yu, S.M.

    1982-04-01

    Conversion of wood to liquid products requires cleavage of bonds which crosslink the wood structure. This study examines a low-severity wood solubilization process utilizing a solvent medium consisting of a small amount of sulfuric acid and a potentially wood-derivable alcohol. In one half hour of reaction time at 250/sup 0/C under 15 psia starting nitrogen pressure, over 95% of the wood (maf) was rendered acetone-soluble. The product is a soft, black, bitumen-like solid at room temperature but readily softens at 140/sup 0/C. Between 25 and 50% of the original wood oxygen, depending on alcohol used, was removed as water. Approximately 2 to 17% of the alcohols were retained in the product. Gel permeation chromatography showed that the product's median molecular weight is around 300. Based on experimental and literature results, a mechanism for wood solubilization is proposed. This involves protonation of the etheric oxygen atoms, leading to subsequent bond scission to form carbonium ions which are stabilized by solvent alkoxylation. At severe conditions, polymerization and condensation reactions result in acetone-insoluble materials.

  14. Engineering grapevine for increased resistance to fungal pathogens without compromising wine stability.

    Science.gov (United States)

    Ferreira, Ricardo B; Monteiro, Sara S; Piçarra-Pereira, M Antonieta; Teixeira, Artur R

    2004-04-01

    The vast majority of wine proteins have recently been identified as pathogenesis-related (PR) proteins. During the growing season, these proteins are expressed in developmentally dependent and inducible manners in grapevine leaves and grape berries, in which they are believed to play an important role in protection against fungal pathogens and possibly other stresses. Because of their inherent resistance to proteolytic attack and to the low pH values characteristic of wines, vinification can be seen as a "purification strategy" for grape PR proteins. The inevitable consequent accumulation of these proteins in wines becomes a technological nuisance because they adversely affect the clarity and stability of wines. Genetically modified vines underexpressing PR proteins would certainly lead to stable wines but would increase the plant susceptibility to fungal attack, and the actual trend seems to be in the opposite direction, that is overexpressing these proteins to obtain plants with enhanced resistance to pathogens--a trend that will probably augment problems associated with protein instability in the resulting wines.

  15. Non_standard Wood

    DEFF Research Database (Denmark)

    Tamke, Martin

    . Using parametric design tools and computer controlled production facilities Copenhagens Centre for IT and Architecture undertook a practice based research into performance based non-standard element design and mass customization techniques. In close cooperation with wood construction software......, but the integration of traditional wood craft techniques. The extensive use of self adjusting, load bearing wood-wood joints contributed to ease in production and assembly of a performance based architecture....

  16. Long-term Cu stabilization and biomass yields of Giant reed and poplar after adding a biochar, alone or with iron grit, into a contaminated soil from a wood preservation site.

    Science.gov (United States)

    Oustriere, Nadège; Marchand, Lilian; Lottier, Nathalie; Motelica, Mikael; Mench, Michel

    2017-02-01

    A 2-year pot experiment was carried out to examine the aging effect of biochar (B), alone or combined with iron grit (Z), on Cu stabilization and plant growth in a contaminated soil (964mg Cu kg -1 ) from a wood preservation site. The experiment consisted in 3 soil treatments, either planted with Arundo donax L. (Ad) or Populus nigra L. (Pn): (1) untreated Cu-contaminated soil (Ad, Pn); (2) Unt+1% (w/w) B (AdB, PnB), and (3) Unt+1% B+1% Z (AdBZ, PnBZ). After 22months, the soil pore water (SPW) was sampled and roots and shoots were harvested. The SPW compositions at 3 and 22months were compared, showing that the SPW Cu 2+ concentration increased again in the PnB and PnBZ soils. Cultivation of A. donax enhanced the dissolved organic matter concentration in the SPW, which decreased its Cu 2+ concentration but promoted its total Cu concentration in the Ad and AdB soils. Adding Z with B reduced both SPW Cu 2+ and Cu concentrations in the pots cultivated by A. donax and P. nigra as compared to B alone. The B and BZ treatments did not enhance root and shoot yields of both plant species as compared to the Unt soil but their shoot Cu concentrations were in the range of common values. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Studies of properties of rubber wood with impregnation of polymer

    Indian Academy of Sciences (India)

    Properties such as dimensional stability, water absorption, hardness, tensile strength, flexural strength, etc of the impregnated wood have been checked and found to be improved by incorporation of GMA as the crosslinker with styrene. The polymer-impregnated wood has also been characterized by FTIR spectroscopy and ...

  18. Iron Stain on Wood

    Science.gov (United States)

    Mark Knaebe

    2013-01-01

    Iron stain, an unsightly blue–black or gray discoloration, can occur on nearly all woods. Oak, redwood, cypress, and cedar are particularly prone to iron stain because these woods contain large amounts of tannin-like extractives. The discoloration is caused by a chemical reaction between extractives in the wood and iron in steel products, such as nails, screws, and...

  19. Wood preservative testing

    Science.gov (United States)

    Rebecca Ibach; Stan T. Lebow

    2012-01-01

    Most wood species used in commercial and residential construction have little natural biological durability and will suffer from biodeterioration when exposed to moisture. Historically, this problem has been overcome by treating wood for outdoor use with toxic wood preservatives. As societal acceptance of chemical use changes, there is continual pressure to develop and...

  20. Wood thermoplastic composites

    Science.gov (United States)

    Daniel F. Caulfield; Craig Clemons; Roger M. Rowell

    2010-01-01

    The wood industry can expand into new sustainable markets with the formation of a new class of composites with the marriage of the wood industry and the plastics industry. The wood component, usually a flour or fiber, is combined with a thermoplastic to form an extrudable, injectable or thermoformable composite that can be used in many non-structural applications....

  1. Wood Formation in Trees

    Science.gov (United States)

    Melanie Mauriat; Gregoire Le Provost; Phillippe Rozenberg; Sylvain Delzon; Nathalie Breda; Bruno Clair; Catherine Coutand; Jean-Christoph Domec; Thierry Fourcaud; Jacqueline Grima-Pettenati; Raul Herrera; Jean-Charles Leple; Nicolas Richet; Jean-Francois Trontin; Christophe Plomion

    2014-01-01

    Among the ecosystem services provided by forests, wood provisioning takes a central position. Wood and derived products have played a critical role in the evolution of human kind and demand for raw material is increasing in a foreseeable future. Wood is used for energy production, construction and a wide variety of products for which different properties are required....

  2. Request for wood samples

    NARCIS (Netherlands)

    NN,

    1977-01-01

    In recent years the wood collection at the Rijksherbarium was greatly expanded following a renewed interest in wood anatomy as an aid for solving classification problems. Staff members of the Rijksherbarium added to the collection by taking interesting wood samples with them from their expeditions

  3. Enhancing durability of wood-based composites with nanotechnology

    Science.gov (United States)

    Carol Clausen

    2012-01-01

    Wood protection systems are needed for engineered composite products that are susceptible to moisture and biodeterioration. Protection systems using nano-materials are being developed to enhance the durability of wood-based composites through improved resistance to biodeterioration, reduced environmental impact from chemical leaching, and improved resistance to...

  4. Wood construction under cold climate

    DEFF Research Database (Denmark)

    Wang, Xiaodong; Hagman, Olle; Sundqvist, Bror

    2014-01-01

    was sensitive to temperature change. MUF, PRF and PVAc resins demonstrated different characters with Norway spruce and Scot pine. At room temperature, all types of adhesive showed relative stability, in terms of shear strength variation. While at low temperature, the shear strength varied considerably. More......) and Scots pine (Pinus sylvestris) joints (150mm x 20mm x 10mm) were bonded with seven commercially available resins (PUR, PVAc, EPI, MF, MUF1, PRF and MUF2) and tested at six temperatures (20, -20, -30, -40, -50 and -60 °C), respectively. Generally, for both species, temperature changes significantly...... affected shear strength of wood joints. As temperature decreased, the shear strength decreased. PUR resin resulted in the strongest shear strength at all temperatures tested. MF resin responded to temperature changes in a similar ways as the PUR resin. The shear strength of wood joints with EPI resins...

  5. Economics of wood dust

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, J.A.

    1980-11-01

    This article reviews the economic effects of wood dust. The most important use of wood today is a fuel, and wood chips and shavings are sources of feedstock for boilers. Other uses include wood chips in the manufacture of particleboard, wood dust as bedding in riding stables and race tracks, as mulch for florists, and as an absorbent in the meat packing industry. The installation of dust collection systems is strongly urged as the consequences of inadequate collection include rapid machine wear, poor environmental conditions for workers, general interference with work, and its combustibility makes it a constant fire hazard.

  6. Microseismic monitoring and numerical simulation on the stability of high-steep rock slopes in hydropower engineering

    Directory of Open Access Journals (Sweden)

    Chun'an Tang

    2015-10-01

    Full Text Available For high-steep slopes in hydropower engineering, damage can be induced or accumulated due to a series of human or natural activities, including excavation, dam construction, earthquake, rainstorm, rapid rise or drop of water level in the service lifetime of slopes. According to the concept that the progressive damage (microseismicity of rock slope is the essence of the precursor of slope instability, a microseismic monitoring system for high-steep rock slopes is established. Positioning accuracy of the monitoring system is tested by fixed-position blasting method. Based on waveform and cluster analyses of microseismic events recorded during test, the tempo-spatial distribution of microseismic events is analyzed. The deformation zone in the deep rock masses induced by the microseismic events is preliminarily delimited. Based on the physical information measured by in situ microseismic monitoring, an evaluation method for the dynamic stability of rock slopes is proposed and preliminarily implemented by combining microseismic monitoring and numerical modeling. Based on the rock mass damage model obtained by back analysis of microseismic information, the rock mass elements within the microseismic damage zone are automatically searched by finite element program. Then the stiffness and strength reductions are performed on these damaged elements accordingly. Attempts are made to establish the correlation between microseismic event, strength deterioration and slope dynamic instability, so as to quantitatively evaluate the dynamic stability of slope. The case studies about two practical slopes indicate that the proposed method can reflect the factor of safety of rock slope more objectively. Numerical analysis can help to understand the characteristics and modes of the monitored microseismic events in rock slopes. Microseismic monitoring data and simulation results can be used to mutually modify the sensitive rock parameters and calibrate the model

  7. Influences of ignition improver additive on ternary (diesel-biodiesel-higher alcohol) blends thermal stability and diesel engine performance

    International Nuclear Information System (INIS)

    Imdadul, H.K.; Masjuki, H.H.; Kalam, M.A.; Zulkifli, N.W.M.; Alabdulkarem, Abdullah; Rashed, M.M.; Ashraful, A.M.

    2016-01-01

    Highlights: • Ignition improver additives makes the biodiesel-alcohol blends more thermally stable. • Density and cetane number improved significantly with EHN mixing. • BP and BSFC improved by adding ignition improver additives. • Nitric oxides and smoke of the EHN treated blends decreased. • CO and HC increased slightly with EHN addition. - Abstract: Pentanol is a long chain alcohol produced from renewable sources and considered as a promising biofuel as a blending component with diesel or biodiesel blends. However, the lower cetane number of alcohols is a limitation, and it is important to increase the overall cetane number of biodiesel fuel blends for efficient combustion and lower emission. In this consideration, ignition improver additive 2-ethylhexyl nitrate (EHN) were used at a proportion of 1000 and 2000 ppm to diesel-biodiesel-pentanol blends. Experiments were conducted in a single cylinder; water-cooled DI diesel engine operated at full throttle and varying speed condition. The thermal stability of the modified ternary fuel blends was evaluated through thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analysis, and the physic-chemical properties of the fuel as well as engine characteristics were studied and compared. The addition of EHN to ternary fuel blends enhanced the cetane number significantly without any significant adverse effect on the other properties. TGA and DSC analysis reported about the improvement of thermal characteristics of the modified blends. It was found that, implementing ignition improver make the diesel-biodiesel-alcohol blends more thermally stable. Also, the brake specific fuel consumption (BSFC), nitric oxides (NO) and smoke emission reduced remarkably with the addition of EHN. Introducing EHN to diesel-biodiesel-alcohol blends increased the cetane number, shorten the ignition delay by increasing the diffusion rate and improve combustion. Hence, the NO and BSFC reduced while, carbon

  8. Wood frame systems for wood homes

    Directory of Open Access Journals (Sweden)

    Julio Cesar Molina

    2010-12-01

    Full Text Available The use of constructive systems that combine strength, speed, with competitive differential techniques and mainly, compromising with the environment, is becoming more popular in Brazil. The constructive system in wood frame for houses of up to five stories is very interesting, because it is a light system, structured in reforested treated wood which allows the combination of several materials, besides allowing speed in the construction and total control of the expenses already in the project phase for being industrialized. The structural behavior of the wood frame is superior to the structural masonry in strength, thermal and acoustic comfort. However, in Brazil, the wood frame is still little known and used, due to lack of technical knowledge about the system, prejudice associated the bad use of the wood as construction material, or still, in some cases, lack of normalization. The aim of this manuscript consists of presenting the main technical characteristics and advantages of the constructive system in wood frame homes, approaching the main stages of the constructive process through examples, showing the materials used in the construction, in addition the main international normative recommendations of the project. Thus, this manuscript also hopes to contribute to the popularization of the wood frame system in Brazil, since it is a competitive, fast and ecologically correct system. Moreover, nowadays, an enormous effort of the technical, commercial and industrial section has been accomplished for the development of this system in the country.

  9. Wood and Other Materials Used to Construct Nonresidential Buildings in the United States 2011 Executive Summary

    Science.gov (United States)

    David B. McKeever

    2013-01-01

    The construction of low-rise nonresidential buildings is an important market for lumber, engineered wood products, and structural and nonstructural wood panels in the United States. This report examines low-rise nonresidential buildings of six or fewer stories. Those with more than six stories are normally severely restricted by building codes from being wood framed....

  10. Wood and Other Materials Used to Construct Nonresidential Buildings in the United States 2011

    Science.gov (United States)

    Craig Adair; David B. McKeever; Chris Gaston; Margaret. Stewart

    2013-01-01

    The construction of low-rise nonresidential buildings is an important market for lumber, engineered wood products, and structural and nonstructural wood panels in the United States. This report examines low-rise nonresidential buildings of six or fewer stories. Those with more than six stories are normally severely restricted by building codes from being wood framed....

  11. Thermal behavior of extracted and delignified pine wood flour

    Science.gov (United States)

    Yao Chen; Mandla A. Tshabalala; Jianmin Gao; Nicole M. Stark; Yongming Fan; Rebecca E. Ibach

    2014-01-01

    To investigate the effect of extractives and lignin on the thermal stability of wood flour (WF), thermogravimetric analysis was used to determine thermal degradation behavior of extracted and delignified mixed pine WF. The contribution of lignin to thermal stability was greater than that of extractives. Removing extractives resulted in improved thermal stability by...

  12. Wood production, wood technology, and biotechnological impacts.

    OpenAIRE

    2007-01-01

    In the year 2001, Prof. Dr. Ursula Kües was appointed at the Faculty of Forest Sciences and Forest Ecology of the Georg-August-University Göttingen to the chair Molecular Wood Biotechnology endowed by the Deutsche Bundesstiftung Umwelt (DBU). Her group studies higher fungi in basic and applied research. Research foci are on mushroom development and on fungal enzymes degrading wood and their applications in wood biotechnology. This book has been edited to thank the DBU for all support given to...

  13. Modeling and simulation of combustion dynamics in lean-premixed swirl-stabilized gas-turbine engines

    Science.gov (United States)

    Huang, Ying

    This research focuses on the modeling and simulation of combustion dynamics in lean-premixed gas-turbines engines. The primary objectives are: (1) to establish an efficient and accurate numerical framework for the treatment of unsteady flame dynamics; and (2) to investigate the parameters and mechanisms responsible for driving flow oscillations in a lean-premixed gas-turbine combustor. The energy transfer mechanisms among mean flow motions, periodic motions and background turbulent motions in turbulent reacting flow are first explored using a triple decomposition technique. Then a comprehensive numerical study of the combustion dynamics in a lean-premixed swirl-stabilized combustor is performed. The analysis treats the conservation equations in three dimensions and takes into account finite-rate chemical reactions and variable thermophysical properties. Turbulence closure is achieved using a large-eddy-simulation (LES) technique. The compressible-flow version of the Smagorinsky model is employed to describe subgrid-scale turbulent motions and their effect on large-scale structures. A level-set flamelet library approach is used to simulate premixed turbulent combustion. In this approach, the mean flame location is modeled using a level-set G-equation, where G is defined as a distance function. Thermophysical properties are obtained using a presumed probability density function (PDF) along with a laminar flamelet library. The governing equations and the associated boundary conditions are solved by means of a four-step Runge-Kutta scheme along with the implementation of the message passing interface (MPI) parallel computing architecture. The analysis allows for a detailed investigation into the interaction between turbulent flow motions and oscillatory combustion of a swirl-stabilized injector. Results show good agreement with an analytical solution and experimental data in terms of acoustic properties and flame evolution. A study of flame bifurcation from a stable

  14. Synthesis of wood treatment alternatives for timber railroad structures.

    Science.gov (United States)

    2011-12-01

    A wealth of information exists on various wood preservatives, treatment techniques, curing practices, and other engineered : controls, along with alternative materials for replacement. This study was initiated to review and synthesize available : inf...

  15. Wood-derived-biochar combined with compost or iron grit for in situ stabilization of Cd, Pb, and Zn in a contaminated soil.

    Science.gov (United States)

    Oustriere, Nadège; Marchand, Lilian; Rosette, Gabriel; Friesl-Hanl, Wolfgang; Mench, Michel

    2017-03-01

    In situ stabilization of Cd, Pb, and Zn in an Austrian agricultural soil contaminated by atmospheric depositions from a smelter plant was assessed with a pine bark chip-derived biochar, alone and in combination with either compost or iron grit. Biochar amendment was also trialed in an uncontaminated soil to detect any detrimental effect. The pot experiment consisted in ten soil treatments (% w/w): untreated contaminated soil (Unt); Unt soil amended with biochar alone (1%: B1; 2.5%: B2.5) and in combination: B1 and B2.5 + 5% compost (B1C and B2.5C), B1 and B2.5 + 1% iron grit (B1Z and B2.5Z); uncontaminated soil (Ctrl); Ctrl soil amended with 1 or 2.5% biochar (CtrlB1, CtrlB2.5). After a 3-month reaction period, the soil pore water (SPW) was sampled in potted soils and dwarf beans were grown for a 2-week period. The SPW Cd, Pb, and Zn concentrations decreased in all amended-contaminated soils. The biochar effects increased with its addition rate and its combination with either compost or iron grit. Shoot Cd and Zn removals by beans were reduced and shoot Cd, Pb, and Zn concentrations decreased to common values in all amended soils except the B1 soil. Decreases in the SPW Cd/Pb/Zn concentrations did not improve the root and shoot yields of plants as compared to the Ctrl soil.

  16. Decision-maker's guide to wood fuel for small industrial energy users. Final report. [Includes glossary

    Energy Technology Data Exchange (ETDEWEB)

    Levi, M. P.; O& #x27; Grady, M. J.

    1980-02-01

    The technology and economics of various wood energy systems available to the small industrial and commercial energy user are considered. This book is designed to help a plant manager, engineer, or others in a decision-making role to become more familiar with wood fuel systems and make informed decisions about switching to wood as a fuel. The following subjects are discussed: wood combustion, pelletized wood, fuel storage, fuel handling and preparation, combustion equipment, retrofitting fossil-fueled boilers, cogeneration, pollution abatement, and economic considerations of wood fuel use. (MHR)

  17. Remarks on orthotropic elastic models applied to wood

    Directory of Open Access Journals (Sweden)

    Nilson Tadeu Mascia

    2006-09-01

    Full Text Available Wood is generally considered an anisotropic material. In terms of engineering elastic models, wood is usually treated as an orthotropic material. This paper presents an analysis of two principal anisotropic elastic models that are usually applied to wood. The first one, the linear orthotropic model, where the material axes L (Longitudinal, R( radial and T(tangential are coincident with the Cartesian axes (x, y, z, is more accepted as wood elastic model. The other one, the cylindrical orthotropic model is more adequate of the growth caracteristics of wood but more mathematically complex to be adopted in practical terms. Specifically due to its importance in wood elastic parameters, this paper deals with the fiber orientation influence in these models through adequate transformation of coordinates. As a final result, some examples of the linear model, which show the variation of elastic moduli, i.e., Young´s modulus and shear modulus, with fiber orientation are presented.

  18. CALIBRATIONS BASED ON NEAR INFRARED SPECTROSCOPIC DATA TO ESTIMATE WOOD-CEMENT PANEL PROPERTIES

    OpenAIRE

    Paulo Ricardo Gherardi Hein; Vânia Aparecida de Sá; Lina Bufalino; Lourival Marin Mendes

    2009-01-01

    Some scientific contributions have used near infrared (NIR) spectroscopy as a rapid and reliable tool for characterizing engineered wood products. However, to our knowledge, there are no published papers that used this technique in order to evaluate wood-cement panels. The main objective of this paper was to evaluate the ability of NIR spectroscopy to estimate physical and mechanical properties in wood-cement panels. The wood-cement panels were produced using Eucalyptus grandis x E. urophylla...

  19. Urban Wood Waste Resource Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Wiltsee, G.

    1998-11-20

    This study collected and analyzed data on urban wood waste resources in 30 randomly selected metropolitan areas in the United States. Three major categories wood wastes disposed with, or recovered from, the municipal solid waste stream; industrial wood wastes such as wood scraps and sawdust from pallet recycling, woodworking shops, and lumberyards; and wood in construction/demolition and land clearing debris.

  20. Fluvial gravel stabilization by net-spinning Hydropsychid caddisflies: exploring the magnitude and geographic scope of ecosystem engineering effect and evaluating resistance to anthropogenic stresses

    Science.gov (United States)

    Daniels, M.; Albertson, L.; Sklar, L. S.; Tumolo, B.; Mclaughlin, M. K.

    2017-12-01

    Several studies have demonstrated the substantial effects that organisms can have on earth surface processes. Known as ecosystem engineers, in streams these organisms maintain, modify, or create physical habitat structure by influencing fluvial processes such as gravel movement, fine sediment deposition and bank erosion. However, the ecology of ecosystem engineers and the magnitude of ecosystem engineering effects in a world increasingly influence by anthropogenically-driven changes is not well understood. Here we present a synthesis of research findings on the potential gravel stabilization effects of Hydropsychid caddisflies, a globally distributed group of net-spinning insects that live in the benthic substrate of most freshwater streams. Hydropsychid caddisflies act as ecosystem engineers because these silk structures can fundamentally alter sediment transport conditions, including sediment stability and flow currents. The silk nets spun by these insects attach gravel grains to one another, increasing the shear stress required to initiate grain entrainment. In a series of independent laboratory experiments, we investigate the gravel size fractions most affected by these silk attachments. We also investigate the role of anthropogenic environmental stresses on ecosystem engineering potential by assessing the impact of two common stressors, high fine sediment loads and stream drying, on silk structures. Finally, an extensive field survey of grain size and Hydropsychid caddisfly population densities informs a watershed-scale network model of Hydropsychid caddisfly gravel stabilizing potential. Our findings provide some of the first evidence that caddisfly silk may be a biological structure that is resilient to various forms of human-mediated stress and that the effects of animal ecosystem engineers are underappreciated as an agent of resistance and recovery for aquatic communities experiencing changes in sediment loads and hydrologic regimes.

  1. Gascoigne Wood - eagle or albatross?

    Energy Technology Data Exchange (ETDEWEB)

    Hoy, H.D.; Lowery, P.A. [RJB Mining (United Kingdom) Limited (United Kingdom). Gascoigne Wood Mine

    1995-11-01

    This paper reviews the history of Gascoigne Wood coal receiving and dispatch centre from conception through to the present. The design and development of the infrastructure is described with particular reference to the spine tunnels, major engineering installations and the system modifications undertaken to maintain a marketable product. Performance parameters are examined and a comparison made of the attributable and surface costs of a Selby Complex Mine with a similar size individual colliery. Finally, the changes envisaged in the future are discussed. 10 figs., 4 tabs.

  2. Remember when science was fun? Encountering 'nuclear fallout in your wood stove' and other mysteries at the Northwestern New Mexico regional and state science and engineering fairs

    International Nuclear Information System (INIS)

    Hylko, J.M.; Miller, M.L.

    1996-01-01

    The Rio Grande Chapter of the Health Physics Society is a proud supporter of the Northwestern New Mexico Regional and State Science and Engineering Fairs. In this role, the chapter provides judges and furnishes monetary awards to recognize those students, between grades 6-12, and their teachers whose projects include the utilization or investigation of ionizing (e.g., gamma) or non-ionizing (e.g., UV exposure, microwaves) radiation. The chapter promotes public information and education about health physics by sending every award winner and sponsoring teacher a copy of career opportunities in health physics, including information about degree programs and scholarships. Also, the chapter provides a 1-year free subscription to the Rio Grande Chapter Newsletter, and publishes the names of the award winners, the titles of their projects, the names of their teachers, and the names of their schools. Furthermore, chapter members are encouraged to assist contestants and award winners by providing mentoring opportunities, and educational resources such as textbooks. This paper reviews the Rio Grande Chapter Science and Engineering Fair Program with respect to judging categories and criteria, project titles, what the chapter has learned from the students, and an overview of the 1995 Regional, State, and International Science and Engineering Fair Programme. (author)

  3. Chapter 9: Wood Energy

    Science.gov (United States)

    Francisco X. Aguilar; Karen Abt; Branko Glavonjic; Eugene Lopatin; Warren  Mabee

    2016-01-01

    The availabilty of information on wood energy continues to improve, particularly for commoditized woodfuels.  Wood energy consumption and production vary in the UNECE region because demand is strngly affected by weather and the prices of competing energy sources.  There has been an increase in wood energy in the power-and-heat sector in the EU28 and North American...

  4. Complex geometries in wood

    DEFF Research Database (Denmark)

    Tamke, Martin; Ramsgaard Thomsen, Mette; Riiber Nielsen, Jacob

    2009-01-01

    The versatility of wood constructions and traditional wood joints for the production of non standard elements was in focus of a design based research. Herein we established a seamless process from digital design to fabrication. A first research phase centered on the development of a robust...... parametric model and a generic design language a later explored the possibilities to construct complex shaped geometries with self registering joints on modern wood crafting machines. The research was carried out as collaboration with industrial partners....

  5. Complex geometries in wood

    DEFF Research Database (Denmark)

    Tamke, Martin; Ramsgaard Thomsen, Mette; Riiber Nielsen, Jacob

    2009-01-01

    The versatility of wood constructions and traditional wood joints for the production of non standard elements was in focus of a design based research. Herein we established a seamless process from digital design to fabrication. A first research phase centered on the development of a robust parame...... parametric model and a generic design language a later explored the possibilities to construct complex shaped geometries with self registering joints on modern wood crafting machines. The research was carried out as collaboration with industrial partners....

  6. Wood pellet seminar

    International Nuclear Information System (INIS)

    Aarniala, M.; Puhakka, A.

    2001-01-01

    The objective of the wood pellet seminar, arranged by OPET Finland and North Karelia Polytechnic, was to deliver information on wood pellets, pellet burners and boilers, heating systems and building, as well as on the activities of wood energy advisors. The first day of the seminar consisted of presentations of equipment and products, and of advisory desks for builders. The second day of the seminar consisted of presentations held by wood pellet experts. Pellet markets, the economy and production, the development of the pellet markets and their problems (in Austria), the economy of heating of real estates by different fuel alternatives, the production, delivery and marketing of wood pellets, the utilization of wood pellet in different utilization sites, the use of wood pellets in detached houses, pellet burners and fireplaces, and conversion of communal real estate houses to use wood pellets were discussed in the presentations. The presentations held in the third day discussed the utilization of wood pellets in power plants, the regional promotion of the production and the use of pellets. The seminar consisted also of visits to pellet manufacturing plant and two pellet burning heating plants

  7. Wood would burn

    International Nuclear Information System (INIS)

    Swithenbank, Jim; Chen, Qun; Zhang, Xiaohui; Sharifi, Vida; Pourkashanian, Mohamed

    2011-01-01

    Absract: In view of the world-wide problem of energy sustainability and greenhouse gas production (carbon dioxide), it is timely to review the issues involved in generating heat and power from all fuels and especially new (to the UK) solid fuels, including high moisture fuels such as wood, SRF, oil shale, tar sands and brown coal, which will become major international fuels as oil and gas become depleted. The combustion properties of some of these materials are significantly different from traditional coal, oil and gas fuels, however the technology proposed herein is also applicable to these conventional fuels. This paper presents some innovative combustion system options and the associated technical factors that must be considered for their implementation. For clarity of understanding, the novel concepts will be largely presented in terms of a currently developing solid fuel market; biomass wood chips. One of the most important characteristics of many solid fuels to be used in the future (including oil shale and brown coal) is their high moisture content of up to 60%. This could be removed by utilising low grade waste heat that is widely available in industry to dry the fuel and thus reduce transport costs. Burning such dried wood for power generation also increases the energy available from combustion and thus acts as a thermal transformer by upgrading the low grade heat to heat available at combustion temperatures. The alternative approach presented here is to recover the latent heat by condensing the extrinsic moisture and the water formed during combustion. For atmospheric combustion, the temperature of the condensed combustion products is below the dew point at about 55-65 o C and is only suitable for recovery in an efficient district heating system. However, in order to generate power from the latent heat, the condensation temperature must be increased to the level where the heat can be used in the thermodynamic power cycle. This can be achieved by

  8. Protein engineering by random mutagenesis and structure-guided consensus of Geobacillus stearothermophilus Lipase T6 for enhanced stability in methanol.

    Science.gov (United States)

    Dror, Adi; Shemesh, Einav; Dayan, Natali; Fishman, Ayelet

    2014-02-01

    The abilities of enzymes to catalyze reactions in nonnatural environments of organic solvents have opened new opportunities for enzyme-based industrial processes. However, the main drawback of such processes is that most enzymes have a limited stability in polar organic solvents. In this study, we employed protein engineering methods to generate a lipase for enhanced stability in methanol, which is important for biodiesel production. Two protein engineering approaches, random mutagenesis (error-prone PCR) and structure-guided consensus, were applied in parallel on an unexplored lipase gene from Geobacillus stearothermophilus T6. A high-throughput colorimetric screening assay was used to evaluate lipase activity after an incubation period in high methanol concentrations. Both protein engineering approaches were successful in producing variants with elevated half-life values in 70% methanol. The best variant of the random mutagenesis library, Q185L, exhibited 23-fold-improved stability, yet its methanolysis activity was decreased by one-half compared to the wild type. The best variant from the consensus library, H86Y/A269T, exhibited 66-fold-improved stability in methanol along with elevated thermostability (+4.3°C) and a 2-fold-higher fatty acid methyl ester yield from soybean oil. Based on in silico modeling, we suggest that the Q185L substitution facilitates a closed lid conformation that limits access for both the methanol and substrate excess into the active site. The enhanced stability of H86Y/A269T was a result of formation of new hydrogen bonds. These improved characteristics make this variant a potential biocatalyst for biodiesel production.

  9. Protein Engineering by Random Mutagenesis and Structure-Guided Consensus of Geobacillus stearothermophilus Lipase T6 for Enhanced Stability in Methanol

    Science.gov (United States)

    Dror, Adi; Shemesh, Einav; Dayan, Natali

    2014-01-01

    The abilities of enzymes to catalyze reactions in nonnatural environments of organic solvents have opened new opportunities for enzyme-based industrial processes. However, the main drawback of such processes is that most enzymes have a limited stability in polar organic solvents. In this study, we employed protein engineering methods to generate a lipase for enhanced stability in methanol, which is important for biodiesel production. Two protein engineering approaches, random mutagenesis (error-prone PCR) and structure-guided consensus, were applied in parallel on an unexplored lipase gene from Geobacillus stearothermophilus T6. A high-throughput colorimetric screening assay was used to evaluate lipase activity after an incubation period in high methanol concentrations. Both protein engineering approaches were successful in producing variants with elevated half-life values in 70% methanol. The best variant of the random mutagenesis library, Q185L, exhibited 23-fold-improved stability, yet its methanolysis activity was decreased by one-half compared to the wild type. The best variant from the consensus library, H86Y/A269T, exhibited 66-fold-improved stability in methanol along with elevated thermostability (+4.3°C) and a 2-fold-higher fatty acid methyl ester yield from soybean oil. Based on in silico modeling, we suggest that the Q185L substitution facilitates a closed lid conformation that limits access for both the methanol and substrate excess into the active site. The enhanced stability of H86Y/A269T was a result of formation of new hydrogen bonds. These improved characteristics make this variant a potential biocatalyst for biodiesel production. PMID:24362426

  10. The effect of wood supply and bleaching process on pulp brightness stability O efeito do tipo de madeira e do processo de branqueamento na estabilidade da alvura da polpa

    Directory of Open Access Journals (Sweden)

    Romildo Lopes Oliveira

    2006-06-01

    Full Text Available One hundred different 5.5-year-old Eucalyptus grandis x Eucalyptus urophylla wood clones were cooked to kappa number 15-17.5 and the resulting kraft pulps oxygen-delignified to kappa 9.5-11.5 under fixed conditions, except for chemical charges. Thirteen samples showing large variations in effective alkali requirement, pulp yield and O-stage efficiency and selectivity were selected for brightness reversion studies. These samples were bleached to 90-91% ISO by DEDD and DEDP sequences and their brightness stability and chemical characteristics determined. Heat reversion of the eucalyptus kraft pulps was strongly influenced by the wood supply, with brightness loss varying in the range of 2.1-3.6 and 0.8-1.7 %ISO for ODEDD and ODEDP bleached pulps, respectively. Pulps bleached by the ODEDP sequence showed reversion values 1.3-1.9 % ISO lower than those bleached by the ODEDD sequence. Pulp carbonyl content decreased by 35-40% during the final peroxide bleaching stage. Carbonyl and carboxyl groups correlated positively with brightness reversion, as did permanganate number and acid soluble lignin. Pulp final viscosity and metal and DCM extractives contents showed no significant correlation with brightness reversion. Pulping, oxygen delignification and ECF bleaching performances also showed no correlation with brightness reversion.Madeiras de 100 diferentes clones de Eucalyptus grandis e Eucalyptus urophylla, com aproximadamente 5,5 anos de idade, foram cozidas ao número kappa 15-17,5. As polpas kraft produzidas foram pré-deslignificadas com oxigênio ao número kappa 9,5-11,5, sob condições fixas. Treze polpas, que mostraram grandes variações na exigência da carga de álcali efetivo e rendimento no processo de polpação, seletividade e eficiência no estágio de Pré-O, foram selecionadas e branqueadas à alvura DE 90-91% ISO pelas seqüências DEDD e DEDP, para estudos de estabilidade de alvura e características químicas. A reversão de

  11. Impact of alginate concentration on the stability of agglomerates made of TiO{sub 2} engineered nanoparticles: Water hardness and pH effects

    Energy Technology Data Exchange (ETDEWEB)

    Loosli, Frédéric, E-mail: frederic.loosli@unige.ch [University of Geneva, Section des Sciences de la Terre et de l’Environnement, Group of Environmental Physical Chemistry, F.-A. Forel Institute (Switzerland); Coustumer, Philippe Le, E-mail: philippe.le-coustumer@u-bordeaux1.fr [Université Bordeaux 3, EA 4592 Géoressources & Environnement, ENSEGID (France); Stoll, Serge, E-mail: serge.stoll@unige.ch [University of Geneva, Section des Sciences de la Terre et de l’Environnement, Group of Environmental Physical Chemistry, F.-A. Forel Institute (Switzerland)

    2015-01-15

    The stability of engineered nanoparticles in natural aquatic systems is of high interest for environmental risk assessment since an already important quantity of these reactive species is entering aquatic systems. In the present study, an important issue is addressed by investigating (i) the influence of divalent cations and water hardness (Mg{sup 2+} and Ca{sup 2+}) in agglomerate formation and (ii) alginate concentration effect on the stability TiO{sub 2} agglomerates formed in environmental freshwater conditions (pH and total hardness) representative of Lake Geneva, France/Switzerland. Our results indicate that the presence of alginate at typical natural organic matter concentration strongly modifies the stability of TiO{sub 2} nanoparticle agglomerates by inducing their partial disagglomeration. Significant TiO{sub 2} nanoparticles redispersion and formation of small fragments are expected to be induced by alginate adsorbed layer formed at the nanoparticle surfaces within the agglomerates.Graphical Abstract.

  12. Antioxidant (A-tocopherol acetate) effect on oxidation stability and NOx emission reduction in methyl ester of Annona oil operated diesel engine

    Science.gov (United States)

    Senthil, R.; Silambarasan, R.; Pranesh, G.

    2017-05-01

    There is a major drawback while using biodiesel as a alternate fuel for compression ignition diesel engine due to lower heating value, higher viscosity, higher density and higher oxides of nitrogen emission. To minimize these drawbacks, fuel additives can contribute towards engine performance and exhaust emission reduction either directly or indirectly. In this current work, the test was conducted to investigate the effect of antioxidant additive (A-tocopherol acetate) on oxidation stability and NOx emission in a of Annona methyl ester oil (MEAO) fueled diesel engine. The A-tocopherol acetate is mixed in different concentrations such as 0.01, 0.02, 0.03 and 0.04% with 100% by vol MEAO. It is concluded that the antioxidant additive very effective in increasing the oxidation stability and in controlling the NOx emission. Further, the addition of antioxidant additive is slight increase the HC, CO and smoke emissions. Hence, A-tocopherol acetate is very effective in controlling the NOx emission with MEAO operated diesel engine without any major modification.

  13. The wood, renewable energy

    International Nuclear Information System (INIS)

    Acket, C.

    2006-12-01

    This document evaluates the french forest situation and its future. Indeed, the wood energy constitutes in France the first renewable energy after the hydraulic. It presents the today situation of the french forest providing statistical data, evaluation of the energy estimation, the carbon fixation, the resources, the perspectives wood energy for 2050, the biofuels and an economic analysis. (A.L.B.)

  14. Wood thermoplastic composites

    Science.gov (United States)

    Daniel F. Caulfield; Craig Clemons; Rodney E. Jacobson; Roger M. Rowell

    2005-01-01

    The term “wood-plastic composites” refers to any number of composites that contain wood (of any form) and either thermoset or thermoplastic polymers. Thermosets or thermoset polymers are plastics that, once cured, cannot be remelted by heating. These include cured resins, such as epoxies and phenolics, plastics with which the forest products industry is most familiar (...

  15. Wood supply and demand

    Science.gov (United States)

    Peter J. Ince; David B. McKeever

    2011-01-01

    At times in history, there have been concerns that demand for wood (timber) would be greater than the ability to supply it, but that concern has recently dissipated. The wood supply and demand situation has changed because of market transitions, economic downturns, and continued forest growth. This article provides a concise overview of this change as it relates to the...

  16. Heat sterilization of wood

    Science.gov (United States)

    Xiping Wang

    2010-01-01

    Two important questions should be considered in heat sterilizing solid wood materials: First, what temperature–time regime is required to kill a particular pest? Second, how much time is required to heat the center of any wood configuration to the kill temperature? The entomology research on the first question has facilitated the development of international standards...

  17. Multifactorial antimicrobial wood protectants

    Science.gov (United States)

    Robert D. Coleman; Carol A. Clausen

    2008-01-01

    It is unlikely that a single antimicrobial compound, whether synthetic or natural, will provide the ‘magic bullet’ for eliminating multiple biological agents affecting wood products. Development of synergistic combinations of selected compounds, especially those derived from natural sources, is recognized as a promising approach to improved wood protection. Recent...

  18. Material model for wood

    NARCIS (Netherlands)

    Sandhaas, C.; Van de Kuilen, J.W.G.

    2013-01-01

    Wood is highly anisotropic and shows ductile behaviour in compression and brittle behaviour in tension and shear where both failure modes can occur simultaneously. A 3D material model for wood based on the concepts of continuum damage mechanics was developed. A material subroutine containing the

  19. Economy of wood supply

    International Nuclear Information System (INIS)

    Imponen, V.

    1993-01-01

    Research and development of wood fuels production was vigorous in the beginning of the 1980's. Techniques and working methods used in combined harvesting and transportation of energy and merchantable wood were developed in addition to separate energy wood delivery. After a ten year silent period the research on this field was started again. At present the underutilization of forest supplies and the environmental effects of energy production based on fossil fuels caused the rebeginning of the research. One alternative for reduction of the price of wood fuels at the utilization site is the integration of energy and merchantable wood deliveries together. Hence the harvesting and transportation devices can be operated effectively, and the organizational costs are decreased as well. The wood delivery costs consist of the stumpage price, the harvesting and transportation costs, and of general expenses. The stumpage price form the largest cost category (over 50 %) of the industrial merchantable wood delivery, and the harvesting and transportation costs in the case of thinningwood delivery. Forest transportation is the largest part of the delivery costs of logging residues. The general expenses, consisting of the management costs and the interest costs of the capital bound to the storages, form a remarkable cost category in delivery of low-rank wood for energy or conversion purposes. The costs caused by the harvesting of thinningwood, the logging residues, chipping and crushing, the lorry transportation are reviewed in this presentation

  20. Stabilization of Polyethylene Glycol in Archaeological Wood

    DEFF Research Database (Denmark)

    Mortensen, Martin Nordvig

    Projektet har fokuseret på polythylen glycol (PEG) stabilitet og nedbrydning i træ fra konserverede skibsvrag som Vasa (Stockholm) og Skuldelev skibene. En række avancerede analyseteknikker er anvendt til at undersøge indtrængningsdybden for forskellige molekylstørrelser PEG i ikke-nedbrudt træ f...

  1. Homogeneous esterification of poplar wood in an ionic liquid under mild conditions: characterization and properties.

    Science.gov (United States)

    Yuan, Tong-Qi; Sun, Shao-Ni; Xu, Feng; Sun, Run-Cang

    2010-11-10

    Wood meal was completely dissolved under constant conditions (130 °C, 6 h) in the ionic liquid 1-butyl-3-methylimidazolium chloride ([C4mim]Cl), and the various factors and potential mechanism of the homogeneous esterification of wood in this reaction medium were mainly studied. The physicochemical properties of the esterified wood were also investigated. It has been shown that highly substituted wood esters could be obtained by reacting wood dissolved in [C(4)mim]Cl with octanoyl chloride in the presence of triethylamine as a neutralizer. The weight percent gain was arranged from 121.5% to 297.4%. All reactions were performed under mild conditions, low excess of reagent, and a short reaction time compared to the heterogeneous chemical modification. Meanwhile, characterization of the derivatives confirmed that the homogeneous esterification was successfully processed. It was also found that thermal stability and morphological properties of the esterified wood were significantly different from those in previous reports. Octanoylation of wood meal in the [C(4)mim]Cl homogeneous system reduced the initial temperature of their thermal degradation and decreased the thermal stability compared to those in unmodified wood meal. Furthermore, the fibrillar appearance of wood meal changed into a relatively more homogeneous macrostructure of the esterfied wood. All these results suggested that homogeneous esterification of poplar wood in [C(4)mim]Cl would enhance the compatibility and improve the processability of wood with synthetic polymers.

  2. Wood adhesives : vital for producing most wood products

    Science.gov (United States)

    Charles R. Frihart

    2011-01-01

    A main route for the efficient utilization of wood resources is to reduce wood to small pieces and then bond them together (Frihart and Hunt 2010). Although humankind has been bonding wood since early Egyptian civilizations, the quality and quantity of bonded wood products has increased dramatically over the past 100 years with the development of new adhesives and...

  3. Effect of antioxidant on the oxidation stability and combustion–performance–emission characteristics of a diesel engine fueled with diesel–biodiesel blend

    International Nuclear Information System (INIS)

    Rashedul, H.K.; Masjuki, H.H.; Kalam, M.A.; Teoh, Y.H.; How, H.G.; Rizwanul Fattah, I.M.

    2015-01-01

    Highlights: • Alexandrian laurel or Calophyllum inophyllum biodiesel blend fulfill the ASTM (D7467) specification. • Addition of antioxidant to biodiesel higher the oxidation stability. • Antioxidant treated blends showed lower NO X and BSFC compared to untreated blend. • Antioxidant treated blends showed higher CO, HC and smoke compared to untreated blend. - Abstract: Alexandrian laurel or Calophyllum inophyllum oil is recently considered one of the most anticipated nonconsumable or nonedible biodiesel sources. An attempt has been made in this study to increase the oxidation stability and investigate the engine performance, emission, and combustion characteristics of a diesel engine by adding 1% (by vol.) of two antioxidants, such as 2,6-Di-tert.-butyl-4-methylphenol and 2,2′-methylenebis (4-methyl-6-tert-butylphenol), in higher percentages of C. inophyllum biodiesel (CB30) with diesel fuel (B0). The experiment was performed on a single-cylinder, water-cooled, direct-injection diesel engine for this purpose. The addition of both antioxidants increased the oxidation stability without significantly changing other physicochemical properties. Results also show that the antioxidants enhanced the start of combustion of biodiesel, which resulted in a short ignition delay. The peak pressure and the peak heat release rate during premixed combustion phase of pure CB30 and its modified blend with antioxidant were higher than those of B0. Both antioxidant blends showed higher brake power, higher brake thermal efficiency, and lower brake specific fuel consumption than pure CB30. Both antioxidants significantly reduced NO X emission; however, CO, HC, and smoke opacity were slightly higher than those of CB30. Based on this study, Alexandrian laurel or C. inophyllum biodiesel blend (CB30) with antioxidant can be used as an alternative fuel in a diesel engine without modifications.

  4. Mechanical performance of wood plastic composites containing decayed wood

    OpenAIRE

    Ayrılmış, Nadir; Kaymakcı, Alperen; Güleç, Türker

    2014-01-01

    This study investigated the potential use of the decayed wood in the manufacture of wood plastic composite (WPC) panel. Scots pine (Pinus sylvestris) sound wood and decayed wood (brown-rot fungi) were used as wood material. Three levels of 30%, 40%, and 50% of sound wood and decayed wood, based on the composition by weight, were mixed with the polypropylene with 3% (based on weight) maleic anhydride grafted PP (MAPP) as a coupling agent. The compound pellets were prepared from twin screw co-r...

  5. Wood surface modification by in-situ sol-gel deposition of hybrid inorganic-organic thin films

    Science.gov (United States)

    Mandla A. Tshabalala; Li-Piin Sung

    2007-01-01

    Interest in the use of nanoparticles of iron, titanium, aluminum, and zinc oxides in transparent coatings for wood is increasing. Such nano-composite coatings have the potential of not only preserving the natural color of the wood, but also stabilizing the wood surface against the combined degradative effects of sunlight and moisture. The nanoparticles can be used as...

  6. Wood-Based Nanotechnologies toward Sustainability.

    Science.gov (United States)

    Jiang, Feng; Li, Tian; Li, Yiju; Zhang, Ying; Gong, Amy; Dai, Jiaqi; Hitz, Emily; Luo, Wei; Hu, Liangbing

    2018-01-01

    With over 30% global land coverage, the forest is one of nature's most generous gifts to human beings, providing shelters and materials for all living beings. Apart from being sustainable, renewable, and biodegradable, wood and its derivative materials are also extremely fascinating from a materials aspect, with numerous advantages including porous and hierarchical structure, excellent mechanical performance, and versatile chemistry. Here, strategies for designing novel wood-based materials via advanced nanotechnologies are summarized, including both the controllable bottom-up assembly from the highly crystalline nanocellulose building block and the more efficient top-down approaches directly from wood. Beyond material design, recent advances regarding the sustainable applications of these novel wood-based materials are also presented, focusing on areas that are traditionally dominated by man-made nonrenewable materials such as plastic, glass, and metals, as well as more advanced applications in the areas of energy storage, wastewater treatment and solar-steam-assisted desalination. With all recent progress pertaining to materials' design and sustainable applications presented, a vision for the future engineering of wood-based materials to promote continuous and healthy progress toward true sustainability is outlined. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Cord Wood Testing in a Non-Catalytic Wood Stove

    Energy Technology Data Exchange (ETDEWEB)

    Butcher, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Trojanowski, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Wei, G. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2014-06-30

    EPA Method 28 and the current wood stove regulations have been in-place since 1988. Recently, EPA proposed an update to the existing NSPS for wood stove regulations which includes a plan to transition from the current crib wood fuel to cord wood fuel for certification testing. Cord wood is seen as generally more representative of field conditions while the crib wood is seen as more repeatable. In any change of certification test fuel, there are questions about the impact on measured results and the correlation between tests with the two different fuels. The purpose of the work reported here is to provide data on the performance of a noncatalytic stove with cord wood. The stove selected has previously been certified with crib wood which provides a basis for comparison with cord wood. Overall, particulate emissions were found to be considerably higher with cord wood.

  8. Application of Algae as Cosubstrate To Enhance the Processability of Willow Wood for Continuous Hydrothermal Liquefaction

    DEFF Research Database (Denmark)

    Sintamarean, Iulia-Maria; Pedersen, Thomas Helmer; Zhao, Xueli

    2017-01-01

    This work proposes a novel strategy to improve the continuous processing of wood slurries in hydrothermal liquefaction systems by coprocessing with algae. Of all algae tested, brown seaweeds and microalgae perform best in preventing slurries dewatering, the main reason for pumpability issues...... with wood slurries. Rheological tests (viscosity–shear rate profile) indicate that the addition of these two algae to the wood slurry causes the highest increase in viscosity, which coincides with improved wood slurries stability and pumpability. Hydrothermal liquefaction of wood-algae slurries at 400 °C...

  9. Abstracts, 21st Annual Meeting Society of Engineering Science, Inc., October 15, 16 and 17, 1984.

    Science.gov (United States)

    1984-01-01

    physical and mechanical properties of shales significantly change on moisture absorption and effect the stability of under- ground excavations...Engineering Syracuse N.Y. 13210 Paper is a nonwoven material composed of pulped wood fibers. The mechanical behavior of the system depends on the properties ...chemical, economical, safety and specific properties are listed and discussed in this paper. -i6 17PM8 488 FLAME RESPONSE TO A SOUND WAVE by Luiz F

  10. Chapter 6: Wood energy and competing wood product markers

    Science.gov (United States)

    Kenneth E. Skog; Robert C. Abt; Karen Abt

    2014-01-01

    Understanding the effect of expanding wood energy markets is important to all wood-dependent industries and to policymakers debating the implementation of public programs to support the expansion of wood energy generation. A key factor in determining the feasibility of wood energy projects (e.g. wood boiler or pellet plant) is the long-term (i.e. 20-30year) supply...

  11. Wood wastes: Uses

    International Nuclear Information System (INIS)

    Cipro, A.

    1993-01-01

    The 1,500 industrial firms manufacturing furniture in the Italian Province of Treviso can generate up to 190,000 tonnes of wood wastes annually. In line with the energy conservation-environmental protection measures contained in Italian Law No. 475/88, this paper indicates convenient uses for these wood wastes - as a raw material for fibreboards or as a fuel to be used in the furniture manufacturing plants themselves and in kilns producing lime. Reference is made to the wood wastes gasification/power generation system being developed by ENEA (the Italian Agency for New Technology, Energy and the Environment)

  12. Fatigue Damage in Wood

    DEFF Research Database (Denmark)

    Clorius, Christian Odin; Pedersen, Martin Bo Uhre; Hoffmeyer, Preben

    1996-01-01

    An investigation of fatigue failure in wood subjected to load cycles in compression parallel to grain is presented. Fatigue failure is found to depend both on the total time under load and on the number of cycles.Recent accelerated fatigue research on wood is reviewed, and a discrepancy between...... to 10 Hz are used. The number of cycles to failure is found to be a poor measure of the fatigue performance of wood. Creep, maximum strain, stiffness and work are monitored throughout the fatigue tests. Accumulated creep is suggested identified with damage and a correlation between stiffness reduction...

  13. Life cycle performances of log wood applied for soil bioengineering constructions

    Science.gov (United States)

    Kalny, Gerda; Strauss-Sieberth, Alexandra; Strauss, Alfred; Rauch, Hans Peter

    2016-04-01

    Nowadays there is a high demand on engineering solutions considering not only technical aspects but also ecological and aesthetic values. Soil bioengineering is a construction technique that uses biological components for hydraulic and civil engineering solutions. Soil bioengineering solutions are based on the application of living plants and other auxiliary materials including among others log wood. This kind of construction material supports the soil bioengineering system as long as the plants as living construction material overtake the stability function. Therefore it is important to know about the durability and the degradation process of the wooden logs to retain the integral performance of a soil bio engineering system. These aspects will be considered within the framework of the interdisciplinary research project „ELWIRA Plants, wood, steel and concrete - life cycle performances as construction materials". Therefore field investigations on soil bioengineering construction material, specifically European Larch wood logs, of different soil bioengineering structures at the river Wien have been conducted. The drilling resistance as a parameter for particular material characteristics of selected logs was measured and analysed. The drilling resistance was measured with a Rinntech Resistograph instrument at different positions of the wooden logs, all surrounded with three different backfills: Fully surrounded with air, with earth contact on one side and near the water surface in wet-dry conditions. The age of the used logs ranges from one year old up to 20 year old. Results show progress of the drilling resistance throughout the whole cross section as an indicator to assess soil bioengineering construction material. Logs surrounded by air showed a higher drilling resistance than logs with earth contact and the ones exposed to wet-dry conditions. Hence the functional capability of wooden logs were analysed and discussed in terms of different levels of degradation

  14. Non_standard Wood

    DEFF Research Database (Denmark)

    Tamke, Martin

    . Using parametric design tools and computer controlled production facilities Copenhagens Centre for IT and Architecture undertook a practice based research into performance based non-standard element design and mass customization techniques. In close cooperation with wood construction software......Non-Standard elements in architecture bear the promise of a better more specific performance (Oosterhuis 2003). A new understanding of design evolves, which is focusing on open ended approaches, able to negotiate between shifting requirements and to integrate knowledge on process and material......, but the integration of traditional wood craft techniques. The extensive use of self adjusting, load bearing wood-wood joints contributed to ease in production and assembly of a performance based architecture....

  15. Wood pellet research program

    International Nuclear Information System (INIS)

    Sohkansanj, S.; Bi, T.

    2006-01-01

    Wood pellets are composed of waste wood materials such as sawmill residue, municipal landfill waste and grain crops. Due to the high temperature combustion used to form the waste materials into the pellet, no additives or glues are necessary to bind them. The pellets are typically used for home heating; heat and power production; poultry bedding; and in biorefineries. This presentation provided an outline of the University of British Columbia wood pellet research and development program. Research at the university is being conducted to develop new types of pellets. Researchers at the program also analyze the physical and chemical properties of pellets in order to optimize pellet density and heating values. Wood pellet modelling and simulation studies are carried out, and various training and education programs are also offered. Research is currently being conducted to develop a reactor for off-gassing experiments. This presentation also provided details of a study investigating the economics of wood pellet production and transport. Pellet production costs and feedstock costs were compared. A summary of the costs and energy inputs of pellet production included details of product storage; transportation and transfer; handling; and transportation to energy plants. It was concluded that more than 35 per cent of the energy content of biomass is used up in the processing and transport of Canadian wood pellets to Europe. refs., tabs., figs

  16. Changing Face of Wood Science in Modern Era: Contribution of Nanotechnology.

    Science.gov (United States)

    Mishra, Pawan Kumar; Giagli, Kyriaki; Tsalagkas, Dimitrios; Mishra, Harshita; Talegaonkar, Sushma; Gryc, Vladimír; Wimmer, Rupert

    2018-02-14

    Wood science and nanomaterials science interact together in two different aspects; a) fabrication of lignocellulosic nanomaterials derived from wood and plant-based sources and b) surface or bulk wood modification by nanoparticles. In this review, we attempt to visualize the impact of nanoparticles on the wood coating and preservation treatments based on a thorough registration of the patent databases. The study was carried out as an overview of the scientifically most followed trends on nanoparticles utilization in wood science and wood protection depicted by recent universal filed patents. This review is exclusively targeted on the solid (timber) wood as a subject material. Utilization of mainly metal nanoparticles as photoprotection, antibacterial, antifungal, antiabrasive and functional component on wood modification treatments was found to be widely patented. Additionally, an apparent minimization in the emission of volatile organic compounds (VOCs) has been succeeded. Bulk wood preservation and more importantly, wood coating, splay the range of strengthening wood dimensional stability and biological degradation, against moisture absorption and fungi respectively. Nanoparticle materials have addressed various issues of wood science in a more efficient and environmental way than the traditional methods. Nevertheless, abundant tests and regulations are still needed before industrializing or recycling these products. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  17. Wood for the trees

    Directory of Open Access Journals (Sweden)

    Rob Garbutt

    2013-10-01

    Full Text Available Our paper focuses on the materiality, cultural history and cultural relations of selected artworks in the exhibition Wood for the trees (Lismore Regional Gallery, New South Wales, Australia, 10 June – 17 July 2011. The title of the exhibition, intentionally misreading the aphorism “Can’t see the wood for the trees”, by reading the wood for the resource rather than the collective wood[s], implies conservation, preservation, and the need for sustaining the originating resource. These ideas have particular resonance on the NSW far north coast, a region once rich in rainforest. While the Indigenous population had sustainable practices of forest and land management, the colonists deployed felling and harvesting in order to convert the value of the local, abundant rainforest trees into high-value timber. By the late twentieth century, however, a new wave of settlers launched a protest movements against the proposed logging of remnant rainforest at Terania Creek and elsewhere in the region. Wood for the trees, curated by Gallery Director Brett Adlington, plays on this dynamic relationship between wood, trees and people. We discuss the way selected artworks give expression to the themes or concepts of productive labour, nature and culture, conservation and sustainability, and memory. The artworks include Watjinbuy Marrawilil’s (1980 Carved ancestral figure ceremonial pole, Elizabeth Stops’ (2009/10 Explorations into colonisation, Hossein Valamanesh’s (2008 Memory stick, and AñA Wojak’s (2008 Unread book (in a forgotten language. Our art writing on the works, a practice informed by Bal (2002, Muecke (2008 and Papastergiadis (2004, becomes a conversation between the works and the themes or concepts. As a form of material excess of the most productive kind (Grosz, 2008, p. 7, art seeds a response to that which is in the air waiting to be said of the past, present and future.

  18. Wood fuel and the environment

    International Nuclear Information System (INIS)

    Foster, C.A.

    1992-01-01

    The purpose of this paper is to try and demonstrate the role that the use of Wood as a Fuel can play in our environment. The term ''Wood Fuel'', for the purposes of these proceedings, refers to the use of wood obtained from the forest or the farm. It does not refer to waste wood from for example buildings. The role of wood fuel in the environment can be assessed at many different levels. In this paper three different scales of ''Environment'' and the role of wood fuel in each, will be considered. These three scales are namely the global environment, the local environment, and the National (community) environment. (Author)

  19. THE EFFECT OF HEAT TREATMENT ON SOME PROPERTIES AND COLOUR IN EUCALYPTUS (Eucalyptus camaldulensis DEHN.) WOOD

    OpenAIRE

    Unsal,O; Korkut,S; Atik,C

    2003-01-01

    Heat treatment is often applied to some wood species to improve dimensional stability. This study evaluated the effect of heat treatment on some physical and mechanical properties and colour of Eucalyptus wood (Eucalyptus camaldulensis Dehn.), which has industrially high usage potential and large plantations in Turkey. Wood specimens from Tarsus, Turkey were subjected to heat treatment in varying temperatures and durations. After the heat treatment, hardness, swelling, ovendry density, and co...

  20. Stabilizing plutonium materials at Hanford: systems engineering for PFP transition project effort on DNFSB 94-1

    Energy Technology Data Exchange (ETDEWEB)

    Huber, T.E., Westinghouse Hanford

    1996-07-02

    This report discusses the basic objectives of the stabilization and packaging activities at the Plutonium Finishing Plant that satisfy the Defense Nuclear Facility Safety Board Recommendation 94-1 by transforming the plutonium materials at hanford into forms or conditions which are suitable for safe storage to appropriate storage criteria; or discard that meets appropriate waste acceptance criteria.

  1. Production and characterization of carbon structures derived from wood

    Science.gov (United States)

    Xie, Xinfeng

    The objective of this research was to produce structural carbon materials from wood, a renewable biomaterial, for advanced material application. A broad range of materials were produced for study including carbonized wood, resin infused carbon composites made from carbonized wood, and carbon nanotubes from wood fibers. The effect of slow heating on the properties of carbonized wood was studied and important carbonized wood properties were found to be produced over a range of heating rates and peak temperatures. Slow heating rates promoted the formation and growth of graphene sheets in turbostratic crystallites, which had a significant influence on the electrical resistivity and Young's modulus of the carbonized wood. A reduction in the rate of heating may be beneficial with respect to carbon properties and the prevention of crack production during the manufacture of large monolithic carbon specimens from wood and wood-based materials. Investigation of selected physical and mechanical properties of resin-infused porous carbon composites made from medium density fiberboard demonstrated that the infused material can be used in specific applications, where high mechanical strength is not required but high dimensional stability at elevated-use temperatures, fire safety, or static dissipation and shielding is required. A unique cyclic heating process has been developed to produce carbon nanotubes directly from wood fibers. Study on the oxidative behavior of carbons derived from cellulose and lignin showed that cellulose carbon ablates faster at a lower temperature in air than lignin carbon when they were prepared at temperatures lower than 500°C due to cellulose carbon's lower content of aromatic structures. It is hypothesized that the formation of carbon nanotubes during the cyclic heating process occurred via template synthesis, with the nanochannels formed from the ablation of cellulose fibrils functioning as a template. Evidence of formation of nanochannels has been

  2. Energy from wood - an overview

    International Nuclear Information System (INIS)

    Nussbaumer, T.

    2000-01-01

    The present publication is the introduction to a series of papers on fundamentals and applications of wood energy. It summarizes figures and data of the actual situation of fuel wood utilization in Switzerland and its potential for the future. Further, the advantages of bio-energy are discussed and the possibilities of funding for bio-energy in Switzerland are described. Wood contributes with 2.5% to the total energy demand in Switzerland nowadays. However, the utilization of wood energy can be more than doubled, which is one of the targets of the Swiss energy policy. The supply chains for the different types of fuel wood are described and specifications and prices of log wood, forestry wood chips and wood residues are presented. The main applications of wood energy are residential heating with manually operated wood boilers and stoves, on the one hand, and heat production with automatic wood furnaces in industry and communities, on the other hand. Automatic furnaces have been promoted in the past ten years and hence they contribute nowadays with more than 50% to the energy supply from wood with a further growing share. As an assistance for further information, a list of institutions and addresses in the field of wood energy in Switzerland is given in the paper. (author)

  3. Turning wood residues into wood revenues

    International Nuclear Information System (INIS)

    Graham, R.G.; Kravetz, Don

    1996-01-01

    Ensyn is a profitable commercial company which derives its revenues from the conversion of wood residues into liquid biofuel and chemicals. The technology, Rapid Thermal Processing (RTP (TM) )is based on extremely fast ''cracking'' of biomass which results in light liquid yields exceeding 70% by weight, from wood. Whether producing chemicals or liquid biofuel, the RTP plant is configured identically and operated essentially in the same mode. Chemicals production simply allows economical production to occur at a lower plant capacity, as low as 2 tonnes/day, than is feasible for a dedicated fuel plant (typically greater than 100 tonnes/day). Ensyn has developed the commercialisation of RTP TM from bench to industrial scale in 10 years. A variety of crative funding initiatives in the early years allowed for capital to be raised for R and D without the loss of intellectual property (IP). The transition years of technology demonstration, prior to full commercialisation, were funded by a blend of revenues from venture capital and public sources, and by quickly tapping into a niche market for RTP TM . The utilisation of the technology at the niche market scale opened the doors to the larger fuel and commodity markets. Once, again, both IP and control of the company were maintained during these years. Flexibility, creativity and expertise are necessary to understand the significance of various financing options (private investments, commercial banking and bond issues) and to integrate these options with various renewable energy, recycling and tax incentives. Understanding these options with various renewable energy, recycling and tax incentives is necessary. Understanding both the core and peripheral needs of the customer are essential in successfully advancing a commercial wood energy venture. Ensyn's experience in these areas is the focus of the paper. (Author)

  4. Precision wood particle feedstocks

    Science.gov (United States)

    Dooley, James H; Lanning, David N

    2013-07-30

    Wood particles having fibers aligned in a grain, wherein: the wood particles are characterized by a length dimension (L) aligned substantially parallel to the grain, a width dimension (W) normal to L and aligned cross grain, and a height dimension (H) normal to W and L; the L.times.H dimensions define two side surfaces characterized by substantially intact longitudinally arrayed fibers; the W.times.H dimensions define two cross-grain end surfaces characterized individually as aligned either normal to the grain or oblique to the grain; the L.times.W dimensions define two substantially parallel top and bottom surfaces; and, a majority of the W.times.H surfaces in the mixture of wood particles have end checking.

  5. Wood-pastures of Europe

    DEFF Research Database (Denmark)

    Plieninger, Tobias; Hartel, Tibor; Martín-López, Berta

    2015-01-01

    Wood-pastures are archetypes of High Nature Value Farmlands in Europe and hold exceptional ecological, social, and cultural values. Yet, wood-pastures have been through a sharp decline all over Europe, mainly due to processes of agricultural intensification and abandonment. Recently, wood......-pastures have found increasing attention from conservation science and policy across Europe. In this paper we (i) perform the first pan-European assessment of wood-pastures, considering individual countries and biogeographic regions, (ii) present the ecological and social-cultural values of a wide diversity...... of wood-pasture systems in Europe, (iii) outline management challenges around wood-pastures, and (iv) provide insights for the policy agenda targeting wood-pastures in Europe. We estimate that wood-pastures cover an area of approximately 203,000km2 in the European Union (EU...

  6. Variation in root wood anatomy

    NARCIS (Netherlands)

    Cutler, D.F.

    1976-01-01

    Variability in the anatomy of root wood of selected specimens particularly Fraxinus excelsior L. and Acer pseudoplatanus L. in the Kew reference microscope slide collection is discussed in relation to generalised statements in the literature on root wood anatomy.

  7. Methane from wood

    International Nuclear Information System (INIS)

    Schulz, T. F.; Barreto, L.; Kypreos, S.; Stucki, S.

    2005-07-01

    The role of wood-based energy technologies in the Swiss energy system in the long-term is examined using the energy-system Swiss MARKAL model. The Swiss MARKAL model is a 'bottom-up' energy-systems optimization model that allows a detailed representation of energy technologies. The model has been developed as a joint effort between the Energy Economics Group (EEG) at Paul Scherrer Institute PSI) and the University of Geneva and is currently used at PSI-EEG. Using the Swiss MARKAL model, this study examines the conditions under which wood-based energy technologies could play a role in the Swiss energy system, the most attractive pathways for their use and the policy measures that could support them. Given the involvement of PSI in the ECOGAS project, especial emphasis is put on the production of bio-SNG from wood via gasification and methanation of syngas and on hydrothermal gasification of woody biomass. Of specific interest as weIl is the fraction of fuel used in passenger cars that could be produced by locally harvested wood. The report is organized as follows: Section 2 presents a brief description of the MARKAL model. Section 3 describes the results of the base case scenario, which represents a plausible, 'middle-of-the-road' development of the Swiss energy system. Section 4 discusses results illustrating the conditions under which the wood-based methanation technology could become competitive in the Swiss energy market, the role of oil and gas prices, subsidies to methanation technologies and the introduction of a competing technology, namely the wood-based Fischer-Tropsch synthesis. FinaIly, section 5 outlines some conclusions from this analysis. (author)

  8. Compressive Fatigue in Wood

    DEFF Research Database (Denmark)

    Clorius, Christian Odin; Pedersen, Martin Bo Uhre; Hoffmeyer, Preben

    1999-01-01

    An investigation of fatigue failure in wood subjected to load cycles in compression parallel to grain is presented. Small clear specimens of spruce are taken to failure in square wave formed fatigue loading at a stress excitation level corresponding to 80% of the short term strength. Four...... frequencies ranging from 0.01 Hz to 10 Hz are used. The number of cycles to failure is found to be a poor measure of the fatigue performance of wood. Creep, maximum strain, stiffness and work are monitored throughout the fatigue tests. Accumulated creep is suggested identified with damage and a correlation...

  9. TCP HolyWood

    OpenAIRE

    Oscar Núñez Mori

    2005-01-01

    We introduce a new end-to-end, sender side Transport Control Protocol called TCP HolyWood or in short TCP-HW. In a simulated wired environment, TCP HolyWood outperforms in average throughput, three of the more important TCP protocols ever made, we are talking about TCP Reno, TCP Westwood, and TCP Vegas; and in average jitter to TCP Reno and TCP Vegas too. In addition, according to Jain’s index, our proposal is as fair as TCP Reno, the Standard. Apresentamos um novo Protocolo de Controle de...

  10. Thermogravimetric analysis of photodegraded acrylic coated lime wood.

    Science.gov (United States)

    Popescu, Carmen-Mihaela; Tibirna, Carmen Mihaela; Vasile, Cornelia

    2011-01-01

    A series of experiments were carried out to investigate the photodegradation of lime wood (Tilia cordata Mill.) coated with acrylic copolymer during artificial UV/Vis light irradiation for 600 h. Photodegradation of the Paraloid B72 films and Paraloid B72 treated lime wood samples was evaluated by thermogravimetry throughout the irradiation period of 100 h. The results obtained indicate a shifting of the DTG maxima to lower temperatures, which may be related to a decrease in the stability of the copolymer and wood during photodegradation. The decrease of weight loss with increasing time of exposure was observed, while the global kinetic parameters for the main peak increases when increasing exposure time of wood to the UV light. Even when the surface of the wood was covered with a thin layer of acrylic resin, some photodegradation reactions of the wood surface occurred. The modifications in the wood structure may be influenced by the newly formed structures from acrylic resin photodegradation. © 2011 The Authors. Photochemistry and Photobiology © 2011 The American Society of Photobiology.

  11. Aspects of sismo-tectonic stability in the South-Eastern region of Brazil of interest to geology of engineering

    International Nuclear Information System (INIS)

    Mioto, J.A.; Hasui, Y.

    1982-01-01

    The occurence of earthquakes in Brazil, mainly in the South-eastern region, and its relationship with the geologic features has been discussed by many Authors since the beginning of this Century. It is difficult to define intraplate seismicity and to understand the actual epirogenic displacent, but the definition of the regional stability is important for enginnering purposes and have been considered through seismologic, morphotectonic and geologic criteria. (Author) [pt

  12. The Asian Wood Pellet Markets

    Science.gov (United States)

    Joseph A. Roos; Allen Brackley

    2012-01-01

    This study examines the three major wood pellet markets in Asia: China, Japan, and South Korea. In contrast to the United States, where most wood pellets are used for residential heating with pellet stoves, a majority of the wood pellets in Asia are used for co-firing at coal-fired power plants. Our analysis indicated that Japan is the largest importer of wood pellets...

  13. Geoenvironmental engineering

    International Nuclear Information System (INIS)

    Shin, Eun Cheol; Park, Jeong Jun

    2009-08-01

    This book deals with definition of soil and scope of clean-up of soil, trend of geoenvironmental engineering at home and foreign countries, main concern of geoenvironmental engineering in domestic and abroad, design and building of landfills such as summary, trend of landfill policy in Korea, post management of landfill facilities, stabilizing and stability of landfill, research method and soil pollution source, restoration technology of soil pollution like restoration technique of oil pollution with thermal processing.

  14. Wood-Based Nanocomposite Derived by in Situ Formation of Organic-Inorganic Hybrid Polymer within Wood via a Sol-Gel Method.

    Science.gov (United States)

    Dong, Xiaoying; Zhuo, Xiao; Wei, Jie; Zhang, Gang; Li, Yongfeng

    2017-03-15

    Solid wood materials and wood-plastic composites as two kinds of lightweight materials are attracting great interest from academia and industry due to their green and recycling nature. However, the relatively lower specific strength limits their wider applications. In particular, solid wood is vulnerable to moisture and decay fungi in nature, resulting in its poor durability for effectively long-term utilization. Inspired from the porous structure of wood, we propose a new design to build a wood-based nanocomposite with higher specific strength and satisfactory durability by in situ generation of organic-inorganic hybrid polymer within wood via a sol-gel method. The derived composite has 50-1200% improvement of impact toughness, 56-192% improvement of tensile strength, and 110-291% improvement of flexural strength over those of typical wood-plastic composites, respectively; and even 34% improvement of specific tensile strength than that of 36A steel; 208% enhancement of hardness; and 156% enhancement of compression strength than those of compared solid wood, respectively; as well as significantly improved dimensional stability and decay resistance over those of untreated natural wood. Such materials could be potentially utilized as lightweight and high-strength materials for applications in construction and automotive industries. This method could be extended to constitute other inorganic nanomaterials for novel organic-inorganic hybrid polymer within wood.

  15. Classroom Demonstrations of Wood Properties.

    Science.gov (United States)

    Foulger, A. N.

    Presented in this manual are 20 activities selected to show some of the properties of wood and how these properties relate to the cellular structure of wood. Each activity includes stated objectives, indicates materials needed, and explains procedures. Illustrations related to the activities, glossary of terms, and photographs of wood structure…

  16. Status of wood energy applications

    International Nuclear Information System (INIS)

    Zerbe, J.I.

    1991-01-01

    In this address, the potential of wood and wood residues to supply future energy needs is examined. In addition, the possible environmental impact of the use of wood fuels on global climate change is discussed. Technologies for the development of new fuels are described

  17. Wrong way: Heating with wood

    Energy Technology Data Exchange (ETDEWEB)

    1981-10-01

    Energy experts state that 'Heating with wood is a hobby, at the most'. Of course, one can save oil by heating with wood, but cost calculations shaw that it is a highly uneconomical substitute. On the other hand, wood can be recommended for thermal insulation.

  18. Ovalbumin as a Wood Adhesive

    Science.gov (United States)

    Charles R. Frihart; Holly Satori; Zhu Rongxian; Michael J. Birkeland

    2014-01-01

    Use of proteins to bond wood dominated industrial production until the middle of the 20th century (1). The ensuing creation of the plywood and glulam beam industries allowed for more efficient use of wood resources than is possible with solid wood products. Many protein sources have been used as adhesives, including plant (soybean) and animal (blood, fish scales,...

  19. Wood construction and magnetic characteristics of impregnated type magnetic wood

    International Nuclear Information System (INIS)

    Oka, Hideo; Hojo, Atsushi; Seki, Kyoushiro; Takashiba, Toshio

    2002-01-01

    The results of experiments involving the AC and DC magnetic characteristics of impregnated type magnetic wood were studied by taking into consideration the wood construction and fiber direction. The experimental results show that the sufficient amount of impregnated magnetic fluid varies depending on the fiber direction and length, and the grain face of the wood material. The impregnated type magnetic wood sample that is fully impregnated by magnetic fluid has a 60% saturation magnetization compared to the saturation magnetization of magnetic fluid. Samples for which the wood fiber direction was the same as the direction of the magnetic path had a higher magnetization intensity and permeability

  20. Wood density explains architectural differentiation across 145 co-occurring tropical tree species

    NARCIS (Netherlands)

    Iida, Y.; Poorter, L.; Sterck, F.J.; Kubo, T.; Kassim, A.R.; Potts, M.D.; Kohyama, T.S.

    2012-01-01

    1. Because of its mechanical properties, wood density may affect the way that trees expand their stem and crown to exploit favourable light conditions in a mechanically stable way. From engineering theory and wood density properties, it is predicted that in terms of biomass investment, low-density

  1. Study of wood polymer combinations from woods of Kashmir

    International Nuclear Information System (INIS)

    Garg, V.P.; Hari Mohan; Rao, K.N.

    1983-01-01

    This report describes the studies conducted to upgrade inferior woods of Kashmir by the application of radiation polymerization process. The process has brought about improvements in the physical and mechanical properties of wood. Wood polymer composite samples have been studied for their use in flooring, wall panelling, roofing shingles, wood carving and in other decorative items. It has been shown that 10% ethyl silicate, when present along with methyl methacrylate or styrene, considerably improves the impact strength and such wood polymer composite samples do not crack even on nailing. Wood polymer composites have been tested for carving and it has been shown that with 50% polymer content, carving quality is preserved. It has also been shown that surface coated wood is more advantageous for use in roofing shingles. (author)

  2. Wood-polymer composite: physical and mechanical properties of some wood species impregnated with styrene and methyl methacrylate

    Directory of Open Access Journals (Sweden)

    Denise Ortigosa Stolf

    2004-12-01

    Full Text Available This study aimed to demonstrate the feasibility of obtaining wood-polymer composites (WPC displaying a performance superior to that of untreated wood from reforested genera. To this end, wood samples of Pine (Pinus caribaea and Eucalyptus (Eucalyptus grandis, whose density is compatible with this process, were impregnated with the polymeric monomers styrene and methyl methacrylate, using benzoyl peroxide to initiate the polymerization process forming free radicals. The vacuum-pressure method was used to impregnate the samples with monomer-initiator solution. The results indicated a significant improvement of all the properties investigated, including dimensional stability, for the Pine-WPC, while Eucalyptus-WPC, owing to the wood's low permeability, showed only increased values of hardness parallel and perpendicular to grain.

  3. History of wood machining

    Science.gov (United States)

    Peter Koch

    1967-01-01

    The history of wood machining is closely tied to advanced in metallurgy and power sources. It has been strongly and continuously shaped by prevailing economic forces and the rise and decline of other contemporary industries. This paper sketches a few of the highlights, with emphasis on developments in North America.

  4. Grant Wood: "American Gothic."

    Science.gov (United States)

    Fitzgerald, Diane M.

    1988-01-01

    Presents a lesson plan which exposes students in grades 10-12 to the visual symbols and historical references contained in Grant Wood's "American Gothic." Includes background information on the artist and the painting, instructional strategies, a studio activity, and evaluation criteria. (GEA)

  5. Wood waste in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Matos, O.; Ribeiro, R. [Biomass Centre for Energy - CBE, Miranda do Corvo (Portugal)

    1997-12-31

    The energy policy of the EC, as well as most of member states points to a sizeable increase of energy production based on renewable energy sources, wood, wood residues, agricultural residues, energy crops including SRF, organic sludges, solid residues, etc. Most recent goals indicate a desirable duplication of today`s percentage by 2010. The reasons for this interest, besides diversification of sources, less dependence on imported fuels, use of endogenous resources, expected decrease of fossil fuel reserves, use of available land, additional employment and income for rural communities, etc., are related to important environmental benefits namely in terms of emissions of hot house gases. Wood waste, resulting from forest operations, cleaning, cultural and final cuttings, and from wood based industries, constitute a special important resource by reason of quality and availability. In addition to this they do not require additional land use and the removal is beneficial. In the run-up to the becoming December`s 1997 `Climate Change Summit` in Kioto, there is mounting pressure on companies to plan on carbon cuts. (author) 6 refs., 1 tab.

  6. Chapter 3: Wood Decay

    Science.gov (United States)

    Dan Cullen

    2014-01-01

    A significant portion of global carbon is sequestered in forest systems. Specialized fungi have evolved to efficiently deconstruct woody plant cell walls. These important decay processes generate litter, soil bound humic substances, or carbon dioxide and water. This chapter reviews the enzymology and molecular genetics of wood decay fungi, most of which are members of...

  7. Tannins in tropical woods

    Energy Technology Data Exchange (ETDEWEB)

    Doat, J.

    1978-01-01

    A preliminary study was made of the chemistry of pyrogallol- and catecholtannins, their general properties and methods of extraction and determination. Three methods of estimation - Lowenthal, powdered hide and spectrophotometry - were compared using two control solutions, four samples of wood and one of bark. Using the empirical powdered hide method, tannins of both types were estimated in wood and bark of various tropical species (some separately and some as a mixture), Moroccan oaks (Quercus suber and Q. ilex), and European oak 9Q. petraea). Further tests were made on the wood and bark of the two mangrove species, Rhizophora mangle and R. racemosa, by subjecting them to successive extraction with a range of solvents. None of the woods tested had as much as the 10% of tannins considered necessary in economic sources. The bark of the two mangroves, of Eucalyptus urophylla and of Prosopis africana had tannin contents over 10% and the latter two species had very favorable tannin/non-tannin ratios. All the tropical species, with the probable exception of E. urophylla, had only catecholtannins. Only the oaks and E. urophylla bark gave positive results when tested for gallotannins.

  8. Thermal Stability and Surface Wettability Studies of Polylactic Acid/Halloysite Nanotube Nanocomposite Scaffold for Tissue Engineering Studies

    Science.gov (United States)

    Nizar, M. Mohd; Hamzah, M. S. A.; Razak, S. I. Abd; Mat Nayan, N. H.

    2018-03-01

    This paper reports the preliminary study about the incorporation of halloysite nanotubes (HNT) into polylactic acid (PLA) scaffold to improve the thermal resistance and surface wettability properties. The fabrication of the porous scaffold requires a simple yet effective technique with low-cost materials within freeze extraction method. The thermal stability of PLA/HNT scaffold compared to neat PLA scaffold achieved with increased content of HNT by 5 wt%. Moreover, the surface wettability of the scaffold also shows a positive impact with high content of HNT by 5 wt%. This new nanocomposite scaffold may have high potential as a suitable template for tissue regeneration.

  9. Manufacture of wood/plastic composites by radiation

    International Nuclear Information System (INIS)

    Iwamoto, Takeo

    1976-01-01

    The manufacture and use of wood/plastic composite (WPC) as an example of wood matrix and wood sawdust/plastic composites (SDP) as an example of plastic matrix are reviewed. The raw material for WPC are mostly vinyl monomers, particularly methyl methacrylate and styrene. The reaction in WPC polymerization is radical polymerization. Researches on the radiation sources mostly resulted in gamma-ray. Electron beam can be applied only to thin products. The future use of WPC may be for furnitures, sporting goods, decorative parts and the like. Vital study on the reduction of manufacturing costs is required, for example, the improvement of reaction and the adoption of continuous process must be considered. The raw materials for SDP are wood sawdust, vinyl monomer (mostly methyl methacrylate) and resins. Electron beam accelerators are the most preferable radiation source because of its high efficiency and safe operation. SDP shows good forming property. The most preferable use of SDP is as interior materials for prefabricated houses, for example, opening frames for bath rooms. Some combination of the technologies of wood engineering, chemical engineering and radiation engineering must be established to develop and maintain the demands. The present radiation sources are forced to grow to large scale industrially, but the establishment of radiation source technology which can be enlarged stepwise is important to keep pace with the development. (Iwakiri, K.)

  10. Food Engineering

    NARCIS (Netherlands)

    Boom, R.M.; Janssen, A.E.M.

    2014-01-01

    Food engineering is a rapidly changing discipline. Traditionally, the main focus was on food preservation and stabilization, whereas trends now are on diversity, health, taste, and sustainable production. Next to a general introduction of the definition of food engineering, this article gives a

  11. Down-Regulation of PoGT47C Expression in Poplar Results in a Reduced Glucuronoxylan Content and an Increased Wood Digestibility by Cellulase

    Science.gov (United States)

    Xylan is the second most abundant polysaccharide in dicot wood. Unraveling the biosynthetic pathway of xylan is important not only for our understanding of the process of wood formation but also for our rational engineering of wood for biofuel production. Although several glycosy...

  12. Tailoring characteristic thermal stability of Ni-Au binary nanocrystals via structure and composition engineering: theoretical insights into structural evolution and atomic inter-diffusion

    Directory of Open Access Journals (Sweden)

    Bangquan Li

    2014-11-01

    Full Text Available We report on the structural evolution and atomic inter-diffusion characteristics of the bimetallic Ni-Au nanocrystals (NCs by molecular dynamics simulations studies. Our results reveal that the thermal stability dynamics of Ni-Au NCs strongly depends on the atomic configurations. By engineering the structural construction with Ni:Au = 1:1 atomic composition, compared with core-shell Au@Ni and alloy NCs, the melting point of core-shell Ni@Au NCs is significantly enhanced up to 1215 K. Unexpectedly, with atomic ratio of Au:Ni= 1:9, the melting process initiates from the atoms in the shell of Ni@Au and alloy NCs, while starts from the core of Au@Ni NCs. The corresponding features and evolution process of structural motifs, mixing and segregation are illustrated via a series of dynamic simulations videos. Moreover, our results revealed that the face centered cubic phase Au0.75Ni0.25 favorably stabilizes in NCs form but does not exist in the bulk counterpart, which elucidates the anomalies of previously reported experimental results on such bimetallic NCs.

  13. The impact of aminated surface ligands and silica shells on the stability, uptake, and toxicity of engineered silver nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Bonventre, Josephine A.; Pryor, Joseph B.; Harper, Bryan J.; Harper, Stacey L., E-mail: stacey.harper@oregonstate.edu [Oregon State University, Department of Environmental and Molecular Toxicology (United States)

    2014-12-15

    Inherent nanomaterial characteristics, composition, surface chemistry, and primary particle size, are known to impact particle stability, uptake, and toxicity. Nanocomposites challenge our ability to predict nanoparticle reactivity in biological systems if they are composed of materials with contrasting relative toxicities. We hypothesized that toxicity would be dominated by the nanoparticle surface (shell vs core), and that modulating the surface ligands would have a direct impact on uptake. We exposed developing zebrafish (Danio rerio) to a series of ∼70 nm amine-terminated silver nanoparticles with silica shells (AgSi NPs) to investigate the relative influence of surface amination, composition, and size on toxicity. Like-sized aminated AgSi and Si NPs were more toxic than paired hydroxyl-terminated nanoparticles; however, both AgSi NPs were more toxic than the Si NPs, indicating a significant contribution of the silver core to the toxicity. Incremental increases in surface amination did not linearly increase uptake and toxicity, but did have a marked impact on dispersion stability. Mass-based exposure metrics initially supported the hypothesis that smaller nanoparticles (20 nm) would be more toxic than larger particles (70 nm). However, surface area-based metrics revealed that toxicity was independent of size. Our studies suggest that nanoparticle surfaces play a critical role in the uptake and toxicity of AgSi NPs, while the impact of size may be a function of the exposure metric used. Overall, uptake and toxicity can be dramatically altered by small changes in surface functionalization or exposure media. Only after understanding the magnitude of these changes, can we begin to understand the biologically available dose following nanoparticle exposure.

  14. Area 2. Use Of Engineered Nanoparticle-Stabilized CO2 Foams To Improve Volumetric Sweep Of CO2 EOR Processes

    Energy Technology Data Exchange (ETDEWEB)

    DiCarlo, David [Univ. of Texas, Austin, TX (United States); Huh, Chun [Univ. of Texas, Austin, TX (United States); Johnston, Keith P. [Univ. of Texas, Austin, TX (United States)

    2015-01-31

    The goal of this project was to develop a new CO2 injection enhanced oil recovery (CO2-EOR) process using engineered nanoparticles with optimized surface coatings that has better volumetric sweep efficiency and a wider application range than conventional CO2-EOR processes. The main objectives of this project were to (1) identify the characteristics of the optimal nanoparticles that generate extremely stable CO2 foams in situ in reservoir regions without oil; (2) develop a novel method of mobility control using “self-guiding” foams with smart nanoparticles; and (3) extend the applicability of the new method to reservoirs having a wide range of salinity, temperatures, and heterogeneity. Concurrent with our experimental effort to understand the foam generation and transport processes and foam-induced mobility reduction, we also developed mathematical models to explain the underlying processes and mechanisms that govern the fate of nanoparticle-stabilized CO2 foams in porous media and applied these models to (1) simulate the results of foam generation and transport experiments conducted in beadpack and sandstone core systems, (2) analyze CO2 injection data received from a field operator, and (3) aid with the design of a foam injection pilot test. Our simulator is applicable to near-injection well field-scale foam injection problems and accounts for the effects due to layered heterogeneity in permeability field, foam stabilizing agents effects, oil presence, and shear-thinning on the generation and transport of nanoparticle-stabilized C/W foams. This report presents the details of our experimental and numerical modeling work and outlines the highlights of our findings.

  15. Moisture Sorption in Artificially aged wood-plastic composites

    Science.gov (United States)

    B. Kristoffer Segerholm; Rebecca E. Ibach; Magnus E.P. Wålinder

    2012-01-01

    Moisture sorption in wood-plastic composites (WPCs) affects their durability and dimensional stability. In certain outdoor exposures, the moisture properties of WPCs are altered due to e.g. cracks induced by swelling and shrinkage of the components, as well as UV degradation or biological attack. The aim of this work was to study the effect of different artificial...

  16. Acetylation of wood components and fourier transform infra-red ...

    African Journals Online (AJOL)

    user

    2011-04-18

    Apr 18, 2011 ... Minato, 2009; Cetin et al., 2010), various catalysts such as pyridine, dimethyl amino pyridine, dimethyl ... dimensional stability by bulking the cell wall polymers and reduces further swelling when the woods ... with toluene : acetone : ethanol mixture [4/1/1, (v/v)], for an addi- tional 6 h using a soxhlet extractor.

  17. High-calcium coal combustion by-products: Engineering properties, ettringite formation, and potential application in solidification and stabilization of selenium and boron

    Energy Technology Data Exchange (ETDEWEB)

    Solem-Tishmack, J.K.; McCarthy, G.J. [North Dakota State Univ., Fargo, ND (United States). Dept. of Chemistry; Docktor, B.; Eylands, K.E.; Thompson, J.S.; Hassett, D.J. [Univ. of North Dakota, Grand Forks, ND (United States). Energy and Environmental Research Center

    1995-04-01

    Four high-calcium coal combustion by-products (two pulverized coal fly ashes (PCFA), a flue gas desulfurization (FGD) residue, and an atmospheric fluidized bed combustion (AFBC) fly ash), were tested for engineering properties and ability to immobilize boron and selenium. These data are needed to explore high-volume utilization in engineered structure or in solidification/stabilization (S/S) technology. Strengths of cured pastes (91 days), varied from as much as 27 MPa (3,900 psi) for one of the PCFA specimens to 4.6 MPa (670 psi) for the FGD specimen. All of the coal by-product pastes developed more than the 0.34 MPa (50 psi) required for S/S applications. Ettringite formation is important to engineering properties and S/S mechanisms. XRD on plain specimens cured for 91 days indicated that the two PCFA pastes formed 5--6% ettringite, the FGD paste formed 22%, and the AFBC paste formed 32%. The hydrating PCFA pastes showed little expansion, the FGD paste contracted slightly, and the AFBC paste expanded by 2.9% over 91 days. Se and B were spiked into the mixing water as sodium selenite, selenate and borate, and for most pastes this had little effect on strength, workability, and expansion. Leaching of ground specimens (cured for 91 days) showed a generally positive correlation between the amount of ettringite formed and resistance to Se and B leaching. Se spiked as selenate was more readily leached than Se spiked as selenite. B showed a high level of fixation.

  18. Rapid Stabilization/Polymerization of Wet Clay Soils; Literature Review

    Science.gov (United States)

    2009-01-15

    Fibre Reinforced Soil." Journal of the Institu- tion of Engineers ( India ), Civil Engineering Division, 83, 135-138. 57. Gow, A. J., Davidson, D. T., and...the Institution of Engineers ( India ) Publication Date: 2002 Purpose of Stabilizer: Stabilizer - Earth Structures Stabilizers Tested: Coir...Purpose of Stabilizer: Stabilizer - Swell potential Stabilizers Tested: Gypsum, lignite , flyash, lime, slime tailings Soil Tested USCS Primary

  19. Young's modulus of BF wood material by longitudinal vibration

    International Nuclear Information System (INIS)

    Phadke, Sushil; Shrivastava, Bhakt Darshan; Mishra, Ashutosh; Dagaonkar, N

    2014-01-01

    All engineered structures are designed and built with consideration of resisting the same fundamental forces of tension, compression, shear, bending and torsion. Structural design is a balance of these internal and external forces. So, it is interesting to calculate the Young's moduli of Borassus Flabellifier BF wood are quite important from the application point of view. The ultrasonic waves are closely related with the elastic and inelastic properties of the materials. In the present study, we measured longitudinal wave ultrasonic velocities in BF wood material by longitudinal vibration method. After measuring ultrasonic velocity in BF wood material, we calculated Young's modulus of Borassus Flabellifier BF wood material. We used ultrasonic interferometer for measuring longitudinal wave ultrasonic velocity in BF wood material made by Mittal Enterprises, New Delhi, India in our laboratory. Borassus Flabellifier BF wood material was collected from Dhar district of Madhya Pradesh, India.

  20. Kickback risk of portable chainsaws while cutting wood of different properties: laboratory tests and deductions.

    Science.gov (United States)

    Dąbrowski, Andrzej

    2015-01-01

    Portable chainsaws are associated with substantial risk and can cause serious injury to operators, especially during kickback. This paper presents new results from research and analyses conducted regarding the impact between the different properties of wood on this occurrence. In an open area, such differences may include: wood species, humidity, temperature and the facing angle of the wood fibres in relation to the kerf and shape of the wood surface that comes in contact with the tip of the guide bar. This paper investigates chainsaw kickback including the research results on kickback and wood-cutting energy, saw chain speed and the efficiency of the chainsaw engine. It also presents conclusions drawn from the tests that can be useful for chainsaw users, showing the dependencies between the different properties of wood and the risk of injury.

  1. Energy efficiency in light-frame wood construction

    Science.gov (United States)

    Gerald E. Sherwood; Gunard Hans

    1979-01-01

    This report presents information needed for design and construction of energy-efficient light-frame wood structures. The opening section discusses improving the thermal performance of a house by careful planning and design. A second section of the report provides technical information on the thermal properties of construction materials, and on the basic engineering...

  2. Mechanical Characteristics of Chemically Degraded Surface Layers of Wood

    Czech Academy of Sciences Publication Activity Database

    Frankl, Jiří; Kloiber, Michal; Drdácký, Miloš; Tippner, J.; Bryscejn, Jan

    2012-01-01

    Roč. 2, č. 11 (2012), s. 694-700 ISSN 2159-5275 R&D Projects: GA ČR(CZ) GPP105/11/P628 Institutional support: RVO:68378297 Keywords : wood * corrosion * defibering * mechanical properties Subject RIV: JN - Civil Engineering http://www.davidpublishing.com

  3. Radioactivity of Wood and Environment

    International Nuclear Information System (INIS)

    Hus, M.; Kosutic, K.; Lulic, S.

    2003-01-01

    Nuclear experiments in the atmosphere and nuclear accidents caused global deposition of artificial radionuclides in the soil of Earth's northern hemisphere, the territory of the Republic of Croatia included. Soil contamination by radionuclides resulted in their deposition in plants growing on the contaminated soil as well as in the trees. Large area of the Republic of Croatia is covered with wood, which is exploited in manufacture of industrial wood and for firewood. From approximately 3 million cubic metres of wood exploited annually, nearly one third serves for firewood. In the process of burning a smaller portion of radionuclides deposited in the wood evaporates and goes to atmosphere while a larger portion is retained in the ash. In this paper are presented the results of natural radionuclides 4 0K , 2 32T h and 2 38U as well as of artificial radionuclide 1 37C s content determination in the wood, wood briquette, charcoal and in ash remained after burning the wood, wood briquette and charcoal. The obtained results are discussed from wood radiocontamination aspect and from the aspect of potential environmental radiocontamination by the products from wood burning process. (author)

  4. Lignin-Retaining Transparent Wood.

    Science.gov (United States)

    Li, Yuanyuan; Fu, Qiliang; Rojas, Ramiro; Yan, Min; Lawoko, Martin; Berglund, Lars

    2017-09-11

    Optically transparent wood, combining optical and mechanical performance, is an emerging new material for light-transmitting structures in buildings with the aim of reducing energy consumption. One of the main obstacles for transparent wood fabrication is delignification, where around 30 wt % of wood tissue is removed to reduce light absorption and refractive index mismatch. This step is time consuming and not environmentally benign. Moreover, lignin removal weakens the wood structure, limiting the fabrication of large structures. A green and industrially feasible method has now been developed to prepare transparent wood. Up to 80 wt % of lignin is preserved, leading to a stronger wood template compared to the delignified alternative. After polymer infiltration, a high-lignin-content transparent wood with transmittance of 83 %, haze of 75 %, thermal conductivity of 0.23 W mK -1 , and work-tofracture of 1.2 MJ m -3 (a magnitude higher than glass) was obtained. This transparent wood preparation method is efficient and applicable to various wood species. The transparent wood obtained shows potential for application in energy-saving buildings. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  5. Lump wood combustion process

    Science.gov (United States)

    Kubesa, Petr; Horák, Jiří; Branc, Michal; Krpec, Kamil; Hopan, František; Koloničný, Jan; Ochodek, Tadeáš; Drastichová, Vendula; Martiník, Lubomír; Malcho, Milan

    2014-08-01

    The article deals with the combustion process for lump wood in low-power fireplaces (units to dozens of kW). Such a combustion process is cyclical in its nature, and what combustion facility users are most interested in is the frequency, at which fuel needs to be stoked to the fireplace. The paper defines the basic terms such as burnout curve and burning rate curve, which are closely related to the stocking frequency. The fuel burning rate is directly dependent on the immediate thermal power of the fireplace. This is also related to the temperature achieved in the fireplace, magnitude of flue gas losses and the ability to generate conditions favouring the full burnout of the fuel's combustible component, which, at once ensures the minimum production of combustible pollutants. Another part of the paper describes experiments conducted in traditional fireplaces with a grate, at which well-dried lump wood was combusted.

  6. Effect of UV exposure on the surface chemistry of wood veneers treated with ionic liquids

    International Nuclear Information System (INIS)

    Patachia, Silvia; Croitoru, Catalin; Friedrich, Christian

    2012-01-01

    In this paper, the influence of four types of imidazolium-based ionic liquids (ILs) on the chemical alteration of the surface of wood veneers exposed to 254 nm UV irradiation have been studied by using image analysis, Fourier transform infrared spectroscopy and surface energy calculation. The wood treated with ionic liquids showed better stability to UV light, as demonstrated by the low lignin, carbonyl index and cellulose crystallinity index variation, as well as very small color modification of the surface with the increase of the UV exposure period, by comparing to non-treated wood. The results show that the tested ionic liquids could be effective as UV stabilizers.

  7. Mechanical properties of wood

    Science.gov (United States)

    David W. Green; Jerrold E. Winandy; David E. Kretschmann

    1999-01-01

    The mechanical properties presented in this chapter were obtained from tests of small pieces of wood termed “clear” and “straight grained” because they did not contain characteristics such as knots, cross grain, checks, and splits. These test pieces did have anatomical characteristics such as growth rings that occurred in consistent patterns within each piece. Clear...

  8. Out of the woods.

    Science.gov (United States)

    Jacobson, J L

    1992-01-01

    Throughout Africa, Asia and Latin America women are pushed out of forests and from their maintenance by governments and private interests for cash crop development disregarding the role of women in conserving forests. In developing countries forests are a source of wood for fuel; 60-80% of women gather wood for family needs in America. Fruits, vegetables, and nuts gathered in woods enhance their diet. Indonesian women pick bananas, mangos, guavas, and avocados from trees around their homes; in Senegal shea-nut butter is made from a local tree fruit to be sold for cash. Women provide labor also in logging, wood processing, and tree nurseries. They make charcoal and grow seedlings for sale. In India 40% of forest income and 75% of forest products export earnings are derived from nonwood resources. Poor, rural women make items out of bamboo, rattan, and rope to sell: 48% of women in an Egyptian province make a living through such activities. In India 600,000 women harvest tendu leaves for use as wrappings for cigarettes. The expansion of commercial tree plantations replacing once communal natural forests has forced poor households to spend up to 4-% of their income on fuel that they used to find in forests. Tribal women in India know the medicinal uses of 300 forest species, and women in Sierra Leone could name 31 products they obtained or made from trees and bushes, while men named only 8 items. Only 1 forestry project appraised by the World Bank during 1984-97 named women as beneficiaries, and only 1 out of 33 rural development programs funded by the World Bank did. Women provide food, fuel, and water for their families in subsistence economies, they know sustainable methods of forestry, yet they are not included in development programs whose success or failure could hinge on more attention to women's contribution and on more equity.

  9. Biomaterial based novel polyurethane adhesives for wood to wood and metal to metal bonding

    Directory of Open Access Journals (Sweden)

    Mitesh Ramanlal Patel

    2009-01-01

    Full Text Available Polyurethane adhesives made from synthetic chemicals are non-biodegradable, costly and difficult to find raw materials from local market. To avoid solid pollution problem, cost effectiveness and easy availability of raw materials, biomaterials based polyurethane adhesives are used in current industrial interest. Direct use of castor oil in polyurethane adhesive gives limited hardness. Modification on active sites of castor oil to utilize double bond of unsaturated fatty acid and carboxyl group yields new modified or activated polyols, which can be utilized for polyurethane adhesive formulation. In view of this, we have synthesized polyurethane adhesives from polyester polyols, castor oil based polyols and epoxy based polyols with Isocyanate adducts based on castor oil and trimethylolpropane. To study the effects of polyurethane adhesive strength (i.e. lap shear strength on wood-to-wood and metal-to-metal bonding through various types of polyols, cross-linking density, isocyanate adducts and also to compare adhesive strength between wood to wood and metal to metal surface. These polyols and polyurethanes were characterized through GPC, NMR and IR-spectroscopy, gel and surface drying time. Thermal stability of PU adhesives was determined under the effect of cross-linking density (NCO/OH ratio. The NCO/OH ratio (1.5 was optimized for adhesives as the higher NCO/OH ratio (2.0 increasing cross-linking density and decreases adhesion. Lower NCO/OH ratio (1.0 provideslow cross-linking density and low strength of adhesives.

  10. Modification of the Sweetness and Stability of Sweet-Tasting Protein Monellin by Gene Mutation and Protein Engineering.

    Science.gov (United States)

    Liu, Qiulei; Li, Lei; Yang, Liu; Liu, Tianming; Cai, Chenggu; Liu, Bo

    2016-01-01

    Natural sweet protein monellin has a high sweetness and low calorie, suggesting its potential in food applications. However, due to its low heat and acid resistance, the application of monellin is limited. In this study, we show that the thermostability of monellin can be improved with no sweetness decrease by means of sequence, structure analysis, and site-directed mutagenesis. We analyzed residues located in the α-helix as well as an ionizable residue C41. Of the mutants investigated, the effects of E23A and C41A mutants were most remarkable. The former displayed significantly improved thermal stability, while its sweetness was not changed. The mutated protein was stable after 30 min incubation at 85°C. The latter showed increased sweetness and slight improvement of thermostability. Furthermore, we found that most mutants enhancing the thermostability of the protein were distributed at the two ends of α-helix. Molecular biophysics analysis revealed that the state of buried ionizable residues may account for the modulated properties of mutated proteins. Our results prove that the properties of sweet protein monellin can be modified by means of bioinformatics analysis, gene manipulation, and protein modification, highlighting the possibility of designing novel effective sweet proteins based on structure-function relationships.

  11. Wood fuels utilization in Central Europe - the wood fuels consumption and the targets of utilization

    International Nuclear Information System (INIS)

    Alakangas, E.

    1999-01-01

    Following subjects are discussed in this presentation: The share of bioenergy of the total energy consumption in EU region; the wood fuels consumption in EU region in 1995; the division of bioenergy utilization (households, wood- based district heating, wood consumption in industry, power generation from wood and residues, biofuels, biogas and sludges); wood fuels consumption in households in EU countries in 1995; wood consumption in France; the additional wood fuel consumption potential in France; Blan bois - wood energy program; French wood energy markets; German wood energy markets; energy consumption in Germany; wood consumption in Bavaria; the wood fuels potential in Bavaria; wood fuels consumption in households in Bavaria; wood fuels consumption for district heating in Bavaria; fuel prices in Bavaria; Environmental regulations in Germany; small boiler markets in Germany; Energy consumption in Austria; small-scale utilization of wood fuels; utilization of wood energy. (Slides, additional information from the author)

  12. Wood Fingerprints:Recognition of Sawn Wood Products

    OpenAIRE

    Pahlberg, Tobias

    2014-01-01

    This thesis deals with wood fingerprints and presents ways to track sawn wood products through an industrial process using cameras. The possibility to identify individual wood products comes from the biological variation of the trees, where the genetic code, environment and breakdown process creates a unique appearance for every board. This application has much of the same challenges as are found in human biometrics applications.The vision for the future is to be able to utilize existing imag...

  13. In vitro culture increases mechanical stability of human tissue engineered cartilage constructs by prevention of microscale scaffold buckling.

    Science.gov (United States)

    Middendorf, Jill M; Shortkroff, Sonya; Dugopolski, Caroline; Kennedy, Stephen; Siemiatkoski, Joseph; Bartell, Lena R; Cohen, Itai; Bonassar, Lawrence J

    2017-11-07

    Many studies have measured the global compressive properties of tissue engineered (TE) cartilage grown on porous scaffolds. Such scaffolds are known to exhibit strain softening due to local buckling under loading. As matrix is deposited onto these scaffolds, the global compressive properties increase. However the relationship between the amount and distribution of matrix in the scaffold and local buckling is unknown. To address this knowledge gap, we studied how local strain and construct buckling in human TE constructs changes over culture times and GAG content. Confocal elastography techniques and digital image correlation (DIC) were used to measure and record buckling modes and local strains. Receiver operating characteristic (ROC) curves were used to quantify construct buckling. The results from the ROC analysis were placed into Kaplan-Meier survival function curves to establish the probability that any point in a construct buckled. These analysis techniques revealed the presence of buckling at early time points, but bending at later time points. An inverse correlation was observed between the probability of buckling and the total GAG content of each construct. This data suggests that increased GAG content prevents the onset of construct buckling and improves the microscale compressive tissue properties. This increase in GAG deposition leads to enhanced global compressive properties by prevention of microscale buckling. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Kraft cooking of gamma irradiated wood, (1)

    International Nuclear Information System (INIS)

    Inaba, Masamitsu; Meshitsuka, Gyosuke; Nakano, Junzo

    1979-01-01

    Studies have been made of kraft cooking of gamma irradiated wood. Beech (Fagus crenata Blume) wood meal suspended in aqueous alkaline alcohol was irradiated up to 1.5 KGy (0.15 Mrad) with gamma rays from a Co-60 source in the presence or absence of oxygen. The irradiated wood meals were washed thoroughly with fresh water, air dried and cooked under the ordinary cooking conditions. The results are summarized as follows: (1) Pre-irradiation in aqueous alkali have negligible effect on kraft cooking. (2) In the case of ethanol addition (50 g/l), pre-irradiation in vacuo shows acceleration of delignification and stabilization of carbohydrates during kraft cooking. Cooked yield gain by pre-irradiation was about 1.2% in all over the range of delignification from 80 to 90%. Aqueous ethanol without alkali also shows positive but smaller effect than that with alkali. (3) Propanol, iso-propanol and butanol show positive but smaller effects than ethanol. However, methanol does not show any positive effect. (4) Irradiation in the presence of oxygen does not show any attractive effect on kraft cooking. (author)

  15. Engineering Ru@Pt Core-Shell Catalysts for Enhanced Electrochemical Oxygen Reduction Mass Activity and Stability.

    Science.gov (United States)

    Jackson, Ariel; Strickler, Alaina; Higgins, Drew; Jaramillo, Thomas Francisco

    2018-01-12

    Improving the performance of oxygen reduction reaction (ORR) electrocatalysts is essential for the commercial efficacy of many renewable energy technologies, including low temperature polymer electrolyte fuel cells (PEFCs). Herein, we report highly active and stable carbon-supported Ru@Pt core-shell nanoparticles (Ru@Pt/C) prepared by a wet chemical synthesis technique. Through rotating disc electrode testing, the Ru@Pt/C achieves an ORR Pt mass-based activity of 0.50 A mg Pt -1 at 0.9 V versus the reversible hydrogen electrode (RHE), which exceeds the activity of the state-of-the-art commercial Pt/C catalyst as well as the Department of Energy 2020 PEFC electrocatalyst activity targets for transportation applications. The impact of various synthetic parameters, including Pt to Ru ratios and catalyst pretreatments (i.e., annealing) are thoroughly explored. Pt-based mass activity of all prepared Ru@Pt/C catalysts was found to exceed 0.4 mg Pt -1 across the range of compositions investigated, with the maximum activity catalyst having a Ru:Pt ratio of 1:1. This optimized composition of Ru@Pt/C catalyst demonstrated remarkable stability after 30,000 accelerated durability cycles (0.6 to 1.0 V vs. RHE at 125 mV s -1 ), maintaining 85% of its initial mass activity. Scanning transmission electron microscopy energy dispersive spectroscopy (STEM-EDS) analysis at various stages of electrochemical testing demonstrated that the Pt shell can provide sufficient protection against the dissolution of the otherwise unstable Ru core.

  16. European wood-fuel trade

    International Nuclear Information System (INIS)

    Hillring, B.; Vinterbaeck, J.

    2001-01-01

    This paper discusses research carried out during the l990s on European wood fuel trade at the Department of Forest Management and Products, SLU, in Sweden. Utilisation of wood-fuels and other biofuels increased very rapidly in some regions during that period. Biofuels are replacing fossil fuels which is an effective way to reduce the future influence of green house gases on the climate. The results indicate a rapid increase in wood-fuel trade in Europe from low levels and with a limited number of countries involved. The chief products traded are wood pellets, wood chips and recycled wood. The main trading countries are, for export, Germany and the Baltic states and, for import, Sweden, Denmark and to some extent the Netherlands. In the future, the increased use of biofuel in European countries is expected to intensify activity in this trade. (orig.)

  17. Torrefaction of wood pellets: New solutions

    Science.gov (United States)

    Zaichenko, V. M.; Shterenberg, V. Ya.

    2017-10-01

    The current state of the market of conventional and torrefied wood pellets and the trends of its development have been analyzed. The advantages and disadvantages of pellets of both types have been compared with other alternative fuels. The consumer segment in which wood pellets are the most competitive has been determined. The original torrefaction technology using exhaust gas heat from a standard gas engine that was developed at the Joint Institute for High Technologies and the scheme of an experimental unit for the elaboration of the technology have been presented. The scheme of the combined operation of a torrefaction unit and a standard hot water boiler, which makes it possible to utilize the heat of exhaust steam-and-gas products of torrefaction with the simultaneous prevention of emissions of harmful substances into the environment, has been proposed. The required correlation between the capacity of the torrefaction unit and the heating boiler house has been estimated for optimal operation under the conditions of the isolated urban village in a region that is distant from the areas of extraction of traditional fuels and, at the same time, has quite sufficient resources of raw materials for the production of wood pellets.

  18. Controlling mold on wood Pallets

    Science.gov (United States)

    Carol A. Clausen

    2012-01-01

    THE WOOD PALLET AND CONTAINER INDUSTRY CONSUMES 4.5 billion board feet (BBF) of hardwoods and 1.8 BBF of softwoods for the annual production of 400-500 million solid wood pallets. While alternative materials such as plastic, corrugated paperboard and metal have entered the market, solid wood remains the material of choice for a majority of pallets on the market (more...

  19. Inoculation Expedition of Agar wood

    International Nuclear Information System (INIS)

    Peng, C.S.; Mohd Fajri Osman; Rusli Zakaria

    2015-01-01

    Inoculation expedition of agar wood is a main field works for researcher in Nuclear Malaysia to prove the real inoculation of agar wood in real jungle. These expeditions was conducted fourth times in the jungles of Malaysia including Gunung Tebu in Terengganu, Murum in Belaga, Sarawak, Kampung Timbang in Kota Belud, Sabah and Nuclear Malaysia itself. This expedition starts from preparation of samples and equipment, transportation into the jungle, searching and recognition of agar wood and lastly, inoculation of the agar wood. Safety aspects precedence set out in the preparation and implementation of this expedition. (author)

  20. Physical changes associated with gamma doses on Wood/ Polypropylene Composites

    Science.gov (United States)

    Ndiaye, Diène; Tidjani, Adams

    2014-08-01

    The effect of gamma- radiation on the morphology, thermal behavior and mechanical properties of wood polypropylene composites has been investigated. Simultaneous thermo gravimetric analysis (TGA) and differential scanning calorimetry (DSC) have been performed on WPC samples of (9.5 ± 0.1) mg. These samples were exposed to different gamma-dose in the range 10 to 100kGy. The results indicated that gamma radiation improves the mechanical properties while the thermal stability is decreased. With gamma radiation, the scanning electron microscopy (SEM) of the micrographs became smoother and we can notice an improvement of interaction between polymer and wood fibers.

  1. Sorption Properties of Steam Treated Wood and Plant Fibres

    DEFF Research Database (Denmark)

    Hoffmeyer, Preben; Jensen, Signe Kamp; Jones, Dennis

    2003-01-01

    Hygrothermal treatment of wood and plant fibres was carried out to improve the dimensional stability of the fibres and products made from these. Fibres of Norway spruce, beech, wheat and hemp were included. The efficiency of the treatment was assessed by studying the moisture sorption properties...... sorption sites. The annual plant fibres proved less susceptible than wood fibres to chemical breakdown from steam treatment. The component most susceptible to chemical breakdown was hemicellulose. Beech, wheat and hemp showed only a modest decrease of cellulose content, even at high temperatures, whereas...

  2. Co-combustion of anthracite coal and wood pellets: Thermodynamic analysis, combustion efficiency, pollutant emissions and ash slagging.

    Science.gov (United States)

    Guo, Feihong; Zhong, Zhaoping

    2018-04-07

    This work presents studies on the co-combustion of anthracite coal and wood pellets in fluidized bed. Prior to the fluidized bed combustion, thermogravimetric analysis are performed to investigate the thermodynamic behavior of coal and wood pellets. The results show that the thermal decomposition of blends is divided into four stages. The co-firing of coal and wood pellets can promote the combustion reaction and reduce the emission of gaseous pollutants, such as SO 2 and NO. It is important to choose the proportion of wood pellets during co-combustion due to the low combustion efficiency caused by large pellets with poor fluidization. Wood pellets can inhibit the volatilization of trace elements, especially for Cr, Ni and V. In addition, the slagging ratio of wood pellets ash is reduced by co-firing with coal. The research on combustion of coal and wood pellets is of great significance in engineering. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Engineering the Pores of Biomass-Derived Carbon: Insights for Achieving Ultrahigh Stability at High Power in High-Energy Supercapacitors.

    Science.gov (United States)

    Thangavel, Ranjith; Kaliyappan, Karthikeyan; Ramasamy, Hari Vignesh; Sun, Xueliang; Lee, Yun-Sung

    2017-07-10

    Electrochemical supercapacitors with high energy density are promising devices due to their simple construction and long-term cycling performance. The development of a supercapacitor based on electrical double-layer charge storage with high energy density that can preserve its cyclability at higher power presents an ongoing challenge. Herein, we provide insights to achieve a high energy density at high power with an ultrahigh stability in an electrical double-layer capacitor (EDLC) system by using carbon from a biomass precursor (cinnamon sticks) in a sodium ion-based organic electrolyte. Herein, we investigated the dependence of EDLC performance on structural, textural, and functional properties of porous carbon engineered by using various activation agents. The results demonstrate that the performance of EDLCs is not only dependent on their textural properties but also on their structural features and surface functionalities, as is evident from the electrochemical studies. The electrochemical results are highly promising and revealed that the porous carbon with poor textural properties has great potential to deliver high capacitance and outstanding stability over 300 000 cycles compared with porous carbon with good textural properties. A very low capacitance degradation of around 0.066 % per 1000 cycles, along with high energy density (≈71 Wh kg -1 ) and high power density, have been achieved. These results offer a new platform for the application of low-surface-area biomass-derived carbons in the design of highly stable high-energy supercapacitors. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Collagen hydrogels incorporated with surface-aminated mesoporous nanobioactive glass: Improvement of physicochemical stability and mechanical properties is effective for hard tissue engineering.

    Science.gov (United States)

    El-Fiqi, Ahmed; Lee, Jae Ho; Lee, Eun-Jung; Kim, Hae-Won

    2013-12-01

    Collagen (Col) hydrogels have poor physicochemical and mechanical properties and are susceptible to substantial shrinkage during cell culture, which limits their potential applications in hard tissue engineering. Here, we developed novel nanocomposite hydrogels made of collagen and mesoporous bioactive glass nanoparticles (mBGns) with surface amination, and addressed the effects of mBGn addition (Col:mBG = 2:1, 1:1 and 1:2) and its surface amination on the physicochemical and mechanical properties of the hydrogels. The amination of mBGn was shown to enable chemical bonding with collagen molecules. As a result, the nanocomposite hydrogels exhibited a significantly improved physicochemical and mechanical stability. The hydrolytic and enzymatic degradation of the Col-mBGn hydrogels were slowed down due to the incorporation of mBGn and its surface amination. The mechanical properties of the hydrogels, specifically the resistance to loading as well as the stiffness, significantly increased with the addition of mBGn and its aminated form, as assessed by a dynamic mechanical analysis. Mesenchymal stem cells cultivated within the Col-mBGn hydrogels were highly viable, with enhanced cytoskeletal extensions, due to the addition of surface aminated mBGn. While the Col hydrogel showed extensive shrinkage (down to ∼20% of initial size) during a few days of culture, the shrinkage of the mBGn-added hydrogel was substantially reduced, and the aminated mBGn-added hydrogel had no observable shrinkage over 21 days. Results demonstrated the effective roles of aminated mBGn in significantly improving the physicochemical and mechanical properties of Col hydrogel, which are ultimately favorable for applications in stem cell culture for bone tissue engineering. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  5. In silico and in vivo stability analysis of a heterologous biosynthetic pathway for 1,4-butanediol production in metabolically engineered E. coli.

    Science.gov (United States)

    Miklóssy, Ildikó; Bodor, Zsolt; Sinkler, Réka; Orbán, Kálmán Csongor; Lányi, Szabolcs; Albert, Beáta

    2017-07-01

    Recently, several approaches have been published in order to develop a functional biosynthesis route for the non-natural compound 1,4-butanediol (BDO) in E. coli using glucose as a sole carbon source or starting from xylose. Among these studies, there was reported as high as 18 g/L product concentration achieved by industrial strains, however BDO production varies greatly in case of the reviewed studies. Our motivation was to build a simple heterologous pathway for this compound in E. coli and to design an appropriate cellular chassis based on a systemic biology approach, using constraint-based flux balance analysis and bi-level optimization for gene knock-out prediction. Thus, the present study reports, at the "proof-of concept" level, our findings related to model-driven development of a metabolically engineered E. coli strain lacking key genes for ethanol, lactate and formate production (ΔpflB, ΔldhA and ΔadhE), with a three-step biosynthetic pathway. We found this strain to produce a limited quantity of 1,4-BDO (.89 mg/L BDO under microaerobic conditions and .82 mg/L under anaerobic conditions). Using glycerol as carbon source, an approach, which to our knowledge has not been tackled before, our results suggest that further metabolic optimization is needed (gene-introductions or knock-outs, promoter fine-tuning) to address the redox potential imbalance problem and to achieve development of an industrially sustainable strain. Our experimental data on culture conditions, growth dynamics and fermentation parameters can consist a base for ongoing research on gene expression profiles and genetic stability of such metabolically engineered E. coli strains.

  6. Stability of parallel flows

    CERN Document Server

    Betchov, R

    2012-01-01

    Stability of Parallel Flows provides information pertinent to hydrodynamical stability. This book explores the stability problems that occur in various fields, including electronics, mechanics, oceanography, administration, economics, as well as naval and aeronautical engineering. Organized into two parts encompassing 10 chapters, this book starts with an overview of the general equations of a two-dimensional incompressible flow. This text then explores the stability of a laminar boundary layer and presents the equation of the inviscid approximation. Other chapters present the general equation

  7. Quantifying arthropod contributions to wood decay

    Science.gov (United States)

    Michael Ulyshen; Terry Wagner

    2013-01-01

    Termites carry large amounts of soil into dead wood, and this behaviour complicates efforts to measure their contributions to wood decay. A novel method for isolating termite soil by burning the wood is described, and some preliminary results are presented.

  8. Corrosion of Fasteners in Wood Treated with Newer Wood Preservatives

    Science.gov (United States)

    Samuel L. Zelinka

    2013-01-01

    This document compiles recent research findings related to corrosion of metals in preservative treated wood into a single report on corrosion of metals in wood. The research was conducted as part of the Research, Technology and Education portion of the National Historic Covered Bridge Preservation (NHCBP) Program administered by the Federal Highway Administration. The...

  9. Wood pole overhead lines

    CERN Document Server

    Wareing, Brian

    2005-01-01

    This new book concentrates on the mechanical aspects of distribution wood pole lines, including live line working, environmental influences, climate change and international standards. Other topics include statutory requirements, safety, profiling, traditional and probabilistic design, weather loads, bare and covered conductors, different types of overhead systems, conductor choice, construction and maintenance. A section has also been devoted to the topic of lightning, which is one of the major sources of faults on overhead lines. The book focuses on the effects of this problem and the strate

  10. Use of wood ash for road stabilisation

    International Nuclear Information System (INIS)

    Lagerkvist, A.; Lind, B.

    2009-01-01

    Due to warmer winters in Sweden, the bearing capacity of forestry roads has become increasingly problematic in recent years. Road stabilization is needed in order to get timber out from the forests. This usually involves the addition of cement to the road body. However, wood ash is a possible substitute for cement because it has similar properties. Using wood ash has the added advantage of saving landfill space. This paper presented an ongoing laboratory study on leaching and mechanical stability, as well as frost-sensitivity using a 30 per cent ash addition to natural soils for reinforcing a forestry road near Timra in central Sweden. The road was being monitored with regard to environmental impact and mechanical properties. The paper discussed the potential of biofuel ashes and the increasing need to reinforce infrastructure due to climate change. The environmental impact from ash use in road constructions was then addressed. It was concluded that the application of ash in road construction would help to strengthen forest roads, make them more resistant to climatic change and render them accessible year-round. 32 refs., 3 tabs., 2 figs.

  11. Engineering of CH 3 NH 3 PbI 3 Perovskite Crystals by Alloying Large Organic Cations for Enhanced Thermal Stability and Transport Properties

    KAUST Repository

    Peng, Wei

    2016-07-28

    The number of studies on organic–inorganic hybrid perovskites has soared in recent years. However, the majority of hybrid perovskites under investigation are based on a limited number of organic cations of suitable sizes, such as methylammonium and formamidinium. These small cations easily fit into the perovskite\\'s three-dimensional (3D) lead halide framework to produce semiconductors with excellent charge transport properties. Until now, larger cations, such as ethylammonium, have been found to form 2D crystals with lead halide. Here we show for the first time that ethylammonium can in fact be incorporated coordinately with methylammonium in the lattice of a 3D perovskite thanks to a balance of opposite lattice distortion strains. This inclusion results in higher crystal symmetry, improved material stability, and markedly enhanced charge carrier lifetime. This crystal engineering strategy of balancing opposite lattice distortion effects vastly increases the number of potential choices of organic cations for 3D perovskites, opening up new degrees of freedom to tailor their optoelectronic and environmental properties.

  12. Preservation of forest wood chips

    Energy Technology Data Exchange (ETDEWEB)

    Kofman, P.D.; Thomsen, I.M.; Ohlsson, C.; Leer, E.; Ravn Schmidt, E.; Soerensen, M.; Knudsen, P.

    1999-01-01

    As part of the Danish Energy Research Programme on biomass utilisation for energy production (EFP), this project concerns problems connected to the handling and storing of wood chips. In this project, the possibility of preserving wood chips of the Norway Spruce (Picea Abies) is addressed, and the potential improvements by anaerobic storage are tested. Preservation of wood chips aims at reducing dry matter losses from extensive heating during storage and to reduce production of fungal spores. Fungal spores pose a health hazards to workers handling the chips. Further the producers of wood chips are interested in such a method since it would enable them to give a guarantee for the delivery of homogeneous wood chips also during the winter period. Three different types of wood chips were stored airtight and further one of these was stored in accordance with normal practise and use as reference. The results showed that airtight storage had a beneficial impact on the quality of the chips: no redistribution of moisture, low dry matter losses, unfavourable conditions for microbial activity of most fungi, and the promotion of yeasts instead of fungi with airborne spores. Likewise the firing tests showed that no combustion problems, and no increased risk to the environment or to the health of staff is caused by anaerobic storage of wood chips. In all, the tests of the anaerobic storage method of forest wood chips were a success and a large-scale test of the method will be carried out in 1999. (au)

  13. Properties of seven Colombian woods

    Science.gov (United States)

    B. A. Bendtsen; M. Chudnoff

    1981-01-01

    Woods from abroad are an important raw material to the forest products industries in the United States. A major concern in effective utilization of this resource is the lack of technical information on many species. This report presents the results of an evaluation of the mechanical properties of small, clear specimens of seven Colombian woods. These results are...

  14. Moisture transport in coated wood

    NARCIS (Netherlands)

    Meel, P.A. van; Erich, S.J.F.; Huinink, H.P.; Kopinga, K.; Jong, J. DE; Adan, O.C.G.

    2011-01-01

    Moisture accumulation inside wood causes favorable conditions for decay. Application of a coating alters the moisture sorption of wood and prevents accumulation of moisture. This paper presents the results of a nuclear magnetic resonance (NMR) study on the influence of a coating on the moisture

  15. The sustainable wood production initiative.

    Science.gov (United States)

    Robert. Deal

    2004-01-01

    To address concerns about sustainable forestry in the region, the Focused Science Delivery Program is sponsoring a three year Sustainable Wood Production Initiative. The Pacific Northwest is one of the world's major timber producing regions, and the ability of this region to produce wood on a sustained yield basis is widely recognized. Concerns relating to the...

  16. Measuring wood specific gravity, correctly

    Science.gov (United States)

    G. Bruce Williamson; Michael C. Wiemann

    2010-01-01

    The specific gravity (SG) of wood is a measure of the amount of structural material a tree species allocates to support and strength. In recent years, wood specific gravity, traditionally a forester’s variable, has become the domain of ecologists exploring the universality of plant functional traits and conservationists estimating global carbon stocks. While these...

  17. On Erdos–Wood's conjecture

    Indian Academy of Sciences (India)

    In this article, we prove that infinite number of integers satsify Erdős–Woods conjecture. Moreover, it follows that the number of natural numbers ≤ satisfies Erdős–Woods conjecture with = 2 is at least /(log ) for some positive constant > 2.

  18. Composites from wood and plastics

    Science.gov (United States)

    Craig Clemons

    2010-01-01

    Composites made from thermoplastics and fillers or reinforcements derived from wood or other natural fibers are a dynamic research area encompassing a wide variety of composite materials. For example, as the use of biopolymers grows, wood and other natural fiber sources are being investigated as renewable sources of fillers and reinforcements to modify performance....

  19. The wood of Merovingian weaponry

    Czech Academy of Sciences Publication Activity Database

    Tegel, W.; Muigg, B.; Büntgen, Ulf

    2016-01-01

    Roč. 65, JAN (2016), s. 148-153 ISSN 0305-4403 R&D Projects: GA MŠk(CZ) EE2.3.20.0248 Institutional support: RVO:67179843 Keywords : Early Middle Ages * Merovingian weaponry * Mineralised wood * Wood anatomy Subject RIV: EH - Ecology, Behaviour Impact factor: 2.602, year: 2016

  20. Public opinion and wood energy

    Science.gov (United States)

    Sarah Hitchner; John Schelhas; Teppo Hujala; J. Peter Brosius

    2014-01-01

    As wood-based bioenergy continues to develop around the world, it will utilize forestlands in new ways and will have different effects on a number of stakeholders, including forest landowners, local communities, extant industries, policymakers, investors, and others. As more stakeholders become involved in the wood energy web, and as the general public becomes more...

  1. Characterisation of wood combustion ashes

    DEFF Research Database (Denmark)

    Maresca, Alberto

    The combustion of wood chips and wood pellets for the production of renewable energy in Denmark increased from 5.7 PJ to 16 PJ during the period 2000-2015, and further increases are expected to occur within the coming years. In 2012, about 22,300 tonnes of wood ashes were generated in Denmark....... Currently, these ashes are mainly landfilled, despite Danish legislation allowing their application onto forest and agricultural soils for fertilising and/or liming purposes. During this PhD work, 16 wood ash samples generated at ten different Danish combustion plants were collected and characterised...... for their composition and leaching properties. Despite the relatively large variations in the contents of nutrients and trace metals, the overall levels were comparable to typical ranges reported in the literature for other wood combustion ashes, as well as with regards to leaching. In general, the composition...

  2. Origin of Petrified Wood Color

    Directory of Open Access Journals (Sweden)

    George Mustoe

    2016-05-01

    Full Text Available Fossil forests have world-wide distribution, commonly preserving mineralized wood that displays vivid hues and complex color patterns. However, the origin of petrified color has received little scientific attention. Color of silicified wood may be influenced by the presence of relict organic matter, but the most significant contribution comes from trace metals. This study reports quantitative analysis of trace metals in 35 silicified wood samples, determined using LA-ICP-MS spectrometry. The most important of these metals is Fe, which can produce a rainbow of hues depending on its abundance and oxidation state. Cr is the dominant colorant for bright green fossil wood from Arizona, USA and Zimbabwe, Africa. Complex color patterns result from the progressive nature of the fossilization process, which causes wood to have varying degrees of permeability during successive episodes of permineralization. These processes include simple diffusion, chromatographic separation, infiltration of groundwater along fractures and void spaces, and oxidation/reduction.

  3. Studies on the effects of storage stability of bio-oil obtained from pyrolysis of Calophyllum inophyllum deoiled seed cake on the performance and emission characteristics of a direct-injection diesel engine.

    Science.gov (United States)

    Rajamohan, Sakthivel; Kasimani, Ramesh

    2018-04-19

    The highly unbalanced nature of bio-oil composition poses a serious threat in terms of storage and utilization of bio-oil as a viable fuel in engines. So it becomes inevitable to study the variations in physicochemical properties of the bio-oil during storage to value its chemical instability, for designing stabilization methodologies. The present study aims to investigate the effects of storage stability of bio-oil extracted from pyrolyzing Calophyllum inophyllum (CI) deoiled seed cake on the engine operating characteristics. The bio-oil is produced in a fixed bed reactor at 500 °C under the constant heating rate of 30 °C/min. All the stability analysis methods involve an accelerated aging procedure based on standards established by ASTM (D5304 and E2009) and European standard (EN 14112). Gas chromatography-mass spectrometry was employed to analytically characterize the unaged and aged bio-oil samples. The results clearly depict that stabilizing Calophyllum inophyllum bio-oil with 10% (w/w) methanol improved its stability than that of the unstabilized sample thereby reducing the aging rate of bio-oil to 0.04 and 0.13 cst/h for thermal and oxidative aging respectively. Engine testing of the bio-oil sample revealed that aged bio-oil samples deteriorated engine performance and increased emission levels at the exhaust. The oxidatively aged sample showed the lowest BTE (24.41%), the highest BSEC (20.14 MJ/kWh), CO (1.51%), HC (132 ppm), NOx (1098 ppm) and smoke opacity (34.8%).

  4. New modelling approaches to predict wood properties from its cellular structure: image-based representation and meshless methods

    OpenAIRE

    Perré, Patrick; Almeida, Giana; Ayouz, Mehdi; Frank, Xavier

    2016-01-01

    Key message The real tissue structure, including local anisotropy directions, is defined from anatomical images of wood. Using this digital representation, thermal/mass diffusivity and mechanical properties (stiffness, large deformation, rupture) are successfully predicted for any anatomical pattern using suitable meshless methods. Introduction Wood, an engineering material of biological origin, presents a huge variability among and within species. Understanding structure/property ...

  5. Projected wood energy impact on US forest wood resources

    Energy Technology Data Exchange (ETDEWEB)

    Skog, K.E. [USDA Forest Service, Madison, WI (United States)

    1993-12-31

    The USDA Forest Service has developed long-term projections of wood energy use as part of a 1993 assessment of demand for and supply of resources from forest and range lands in the United States. To assess the impact of wood energy demand on timber resources, a market equilibrium model based on linear programming was developed to project residential, industrial, commercial, and utility wood energy use from various wood energy sources: roundwood from various land sources, primary wood products mill residue, other wood residue, and black liquor. Baseline projections are driven by projected price of fossil fuels compared to price of wood fuels and the projected increase in total energy use in various end uses. Wood energy use is projected to increase from 2.67 quad in 1986 to 3.5 quad in 2030 and 3.7 quad in 2040. This is less than the DOE National Energy Strategy projection of 5.5 quad in 2030. Wood energy from forest sources (roundwood) is projected to increase from 3.1 billion (10{sup 9}) ft{sup 3} in 1986 to 4.4. billion ft{sup 3} in 2030 and 4.8 billion ft{sup 3} in 2040 (88, 124 and 136 million m{sup 3}, respectively). This rate of increase of roundwood use for fuel -- 0.8 percent per year -- is virtually the same as the projected increase rate for roundwood for pulpwood. Pulpwood roundwood is projected to increase from 4.2 billion ft{sup 3} in 1986 to 6.0 billion ft{sup 3} in 2030 and 6.4 billion ft{sup 3} in 2040 (119, 170 and 183 million m{sup 3}, respectively).

  6. Hydrolysis of glycosidically bound flavour compounds from oak wood by Oenococcus oeni.

    Science.gov (United States)

    Bloem, Audrey; Lonvaud-Funel, Aline; de Revel, Gilles

    2008-02-01

    Malolactic fermentation (MLF), which is conducted by lactic acid bacteria (LAB), has a significant influence on the stability and organoleptic quality of wine. Recent studies have shown that when MLF is carried out in oak wood barrels, LAB were also able to interact with wood and increase volatile compound contents such as vanillin during MLF. The release of these compounds indicates that LAB may convert vanillin precursors present in oak wood. In this work, the effect of commercial glycosidases on the released vanillin was firstly studied. This aldehyde is present in wood extracts in monoglycosidic forms where the major glycones are arabinose and xylose. Other aglycons released during MLF in barrels, syringaldehyde and whisky-lactones, can be considered as other sources of aroma. Secondly, strains selected with high activities toward glycoside substrates could hydrolyse vanillin glycoside precursors from oak wood with the same efficiency as commercial enzymes.

  7. EFFECT OF ARTIFICIAL WEATHERING ON WOOD LAMINATES COLOR TREATED WITH TWO FINISHING PRODUCTS

    Directory of Open Access Journals (Sweden)

    Thais Jacob Mendes

    2016-03-01

    Full Text Available Weathering is one of the main reasons for the degradation of wood, especially its color. The application of finishes minimizes these effects. This study aimed to monitor the effect of artificial weathering on wood veneer of the species cumaru (Dipteryx odorata and pau marfim (Balfourodendron riedelianum with two finishes, the marine varnish and Cetol, with monitoring using a spectrophotometer. The samples were subjected to cycles of exposure to weathering for 20, 40, 52, 76, 124, 226, 430, 838 and 960 hours. The colorimetric parameters (L*, a*, b*, C and h* were measured before treatment, after application of the products and during the weathering time intervals. The application of finishes darkened veneer of cumaru wood and pau marfim in nature. However, in higher weathering times, both species returned to a lighter color, and even became lighter than the natural wood. The use of Cetol was more efficient, giving greater stability in the conservation of wood color of the species studied.

  8. Bio-Based Adhesives and Evaluation for Wood Composites Application

    Directory of Open Access Journals (Sweden)

    Fatemeh Ferdosian

    2017-02-01

    Full Text Available There has been a rapid growth in research and innovation of bio-based adhesives in the engineered wood product industry. This article reviews the recent research published over the last few decades on the synthesis of bio-adhesives derived from such renewable resources as lignin, starch, and plant proteins. The chemical structure of these biopolymers is described and discussed to highlight the active functional groups that are used in the synthesis of bio-adhesives. The potentials and drawbacks of each biomass are then discussed in detail; some methods have been suggested to modify their chemical structures and to improve their properties including water resistance and bonding strength for their ultimate application as wood adhesives. Moreover, this article includes discussion of techniques commonly used for evaluating the petroleum-based wood adhesives in terms of mechanical properties and penetration behavior, which are expected to be more widely applied to bio-based wood adhesives to better evaluate their prospect for wood composites application.

  9. Wood power in North Carolina

    Energy Technology Data Exchange (ETDEWEB)

    Cleland, J.G.; Guessous, L. [Research Triangle Institute, Research Triangle Park, NC (United States)

    1993-12-31

    North Carolina (NC) is one of the most forested states, and supports a major wood products industry. The NC Department of Natural Resources sponsored a study by Research Triangle Institute to examine new, productive uses of the State`s wood resources, especially electric power generation by co-firing with coal. This paper summarizes our research of the main factors influencing wood power generation opportunities, i.e., (1) electricity demand; (2) initiative and experience of developers; (3) available fuel resources; (4) incentives for alternate fuels; and (5) power plant technology and economics. The results cover NC forests, short rotation woody crops, existing wood energy facilities, electrical power requirements, and environmental regulations/incentives. Quantitative assessments are based on the interests of government agencies, utilities, electric cooperatives, developers and independent power producers, forest products industries, and the general public. Several specific, new opportunities for wood-to-electricity in the State are identified and described. Comparisons are made with nationwide resources and wood energy operations. Preferred approaches in NC are co-generation in existing or modified boilers and in dedicated wood power plants in forest industry regions. Co-firing is mainly an option for supplementing unreliable primary fuel supplies to existing boilers.

  10. Cooling of wood briquettes

    Directory of Open Access Journals (Sweden)

    Adžić Miroljub M.

    2013-01-01

    Full Text Available This paper is concerned with the experimental research of surface temperature of wood briquettes during cooling phase along the cooling line. The cooling phase is an important part of the briquette production technology. It should be performed with care, otherwise the quality of briquettes could deteriorate and possible changes of combustion characteristics of briquettes could happen. The briquette surface temperature was measured with an IR camera and a surface temperature probe at 42 sections. It was found that the temperature of briquette surface dropped from 68 to 34°C after 7 minutes spent at the cooling line. The temperature at the center of briquette, during the 6 hour storage, decreased to 38°C.

  11. Genetic modification of wood quality for second-generation biofuel production.

    Science.gov (United States)

    Lu, Shanfa; Li, Laigeng; Zhou, Gongke

    2010-01-01

    How the abundant tree biomass resources can be efficiently used for future biofuel production has attracted a great deal of interest and discussion in the past few years. Capable technologies are expected to be developed to realize the production of biofuel from wood biomass. A significant effort is put into the field of modifying wood properties of trees and simplifying the process of biomass-to-ethanol conversion, which includes mainly genetic engineering of lignin, cellulose and hemicellulose of woods. Current research in this field has achieved some promising results and opened up new opportunities to utilize wood biomass efficiently. This review will discuss the main developments in genetic modification of lignin, cellulose and hemicellulose biosynthesis in trees as well as other potential genetic technology of biofuel production from wood biomass.

  12. The Carbon Impacts of Wood Products

    Science.gov (United States)

    Richard Bergman; Maureen Puettmann; Adam Taylor; Kenneth E. Skog

    2014-01-01

    Wood products have many environmental advantages over nonwood alternatives. Documenting and publicizing these merits helps the future competitiveness of wood when climate change impacts are being considered. The manufacture of wood products requires less fossil fuel than nonwood alternative building materials such as concrete, metals, or plastics. By nature, wood is...

  13. Physical properties and moisture relations of wood

    Science.gov (United States)

    William Simpson; Anton TenWolde

    1999-01-01

    The versatility of wood is demonstrated by a wide variety of products. This variety is a result of a spectrum of desirable physical characteristics or properties among the many species of wood. In many cases, more than one property of wood is important to the end product. For example, to select a wood species for a product, the value of appearance- type properties,...

  14. Moisture relations and physical properties of wood

    Science.gov (United States)

    Samuel V. Glass; Samuel L. Zelinka

    2010-01-01

    Wood, like many natural materials, is hygroscopic; it takes on moisture from the surrounding environment. Moisture exchange between wood and air depends on the relative humidity and temperature of the air and the current amount of water in the wood. This moisture relationship has an important influence on wood properties and performance. Many of the challenges of using...

  15. Wood Flour Moulding Technology: Implications for Technical ...

    African Journals Online (AJOL)

    User

    2011-04-19

    Apr 19, 2011 ... selected dry wood by grinding. Interest in this modern industrial practice in wood anchors ... flour moulding technology minimizes atmospheric pollution, reduces cost of wood waste disposal and curbs, ... Zhang and Wolcott,. 2007). Wood Flour Moulding Technology: Implications for Technical Education ...

  16. Fire Safety Design of Wood Structures

    DEFF Research Database (Denmark)

    Hertz, Kristian Dahl

    2006-01-01

    Lecture Notes on Fire Safety Design of Wood Structures including charring of wood and load bearing capacity of beams, columns, and connections.......Lecture Notes on Fire Safety Design of Wood Structures including charring of wood and load bearing capacity of beams, columns, and connections....

  17. Wood-based composites and panel products

    Science.gov (United States)

    John A. Youngquist

    1999-01-01

    Because wood properties vary among species, between trees of the same species, and between pieces from the same tree, solid wood cannot match reconstituted wood in the range of properties that can be controlled in processing. When processing variables are properly selected, the end result can sometimes surpass nature’s best effort. With solid wood, changes in...

  18. Wood Technology: Techniques, Processes, and Products

    Science.gov (United States)

    Oatman, Olan

    1975-01-01

    Seven areas of wood technology illustrates applicable techniques, processes, and products for an industrial arts woodworking curriculum. They are: wood lamination; PEG (polyethylene glycol) diffusion processes; wood flour and/or particle molding; production product of industry; WPC (wood-plastic-composition) process; residential construction; and…

  19. FIRE INSURANCE AND WOOD SCHOOL BUILDINGS.

    Science.gov (United States)

    PURCELL, FRANK X.

    A COMPARISON OF FIRE INSURANCE COSTS OF WOOD, MASONRY, STEEL AND CONCRETE STRUCTURES SHOWS FIRE INSURANCE PREMIMUMS ON WOOD STRUCTURES TEND TO BE HIGHER THAN PREMIUMS ON MASONRY, STEEL AND CONCRETE BUILDINGS, HOWEVER, THE INITIAL COST OF THE WOOD BUILDINGS IS LOWER. DATA SHOW THAT THE SAVINGS ACHIEVED IN THE INITIAL COST OF WOOD STRUCTURES OFFSET…

  20. The challenge of bonding treated wood

    Science.gov (United States)

    Charles R. Frihart

    2004-01-01

    Wood products are quite durable if exposure to moisture is minimized; however, most uses of wood involve considerable exposure to moisture. To preserve the wood, chemicals are used to minimize moisture pickup, to prevent insect attack, and/or to resist microbial growth. The chemicals used as preservatives can interfere with adhesive bonds to wood. Given the many...

  1. Combustion properties of wood impregnated with commercial ...

    African Journals Online (AJOL)

    ajl yemi

    2011-12-19

    Dec 19, 2011 ... ... thermal conductivity and the fact that wood char is formed when wood is burned. In order to reduce flammability and provide safety, wood is treated with fire-retardant chemicals. In other words, the combustibility of wood may be reduced with flame- retardant or fire-retardant materials (Nussbaum, 1988;.

  2. Potential wood protection strategies using physiological requirements of wood degrading fungi

    NARCIS (Netherlands)

    Sailer, M.F.; Etten, B.D. van

    2004-01-01

    Due to the increasing restrictions in the use of wood preserving biocides a number of potential biocide free wood preserving alternatives are currently assessed. Wood degrading fungi require certain conditions in the wood in order to be able to use wood as a food source. This paper discusses the

  3. COMBUSTION PROPERTIES OF EUCALYPTUS WOOD

    Directory of Open Access Journals (Sweden)

    Yalçın ÖRS

    1999-03-01

    Full Text Available In this study, the combustion properties of some impregnation materials (abiotic and biotic factors used for eucalyptus wood in interior or exterior environments were investigated. The experimental samples were prepared from Eucalyptus wood based on ASTM-D-1413-76 Tanalith-CBC, boric acid, borax, vacsol-WR, immersol-WR, polyethylen glycole-400 and ammonium sulphate were used as an impregnation material. The results indicated that, vacuum treatment on Eucalyptus gave the lowest retention value of salts. Compounds containing boron+salt increased fire resistance however water repellents decreased the wood flammability.

  4. Geologic processes in the RWMC area, Idaho National Engineering Laboratory: Implications for long term stability and soil erosion at the radioactive waste management complex

    Energy Technology Data Exchange (ETDEWEB)

    Hackett, W.R.; Tullis, J.A.; Smith, R.P. [and others

    1995-09-01

    The Radioactive Waste Management Complex (RWMC) is the disposal and storage facility for low-level radioactive waste at the Idaho National Engineering Laboratory (INEL). Transuranic waste and mixed wastes were also disposed at the RWMC until 1970. It is located in the southwestern part of the INEL about 80 km west of Idaho Falls, Idaho. The INEL occupies a portion of the Eastern Snake River Plain (ESRP), a low-relief, basalt, and sediment-floored basin within the northern Rocky Mountains and northeastern Basin and Range Province. It is a cool and semiarid, sagebrush steppe desert characterized by irregular, rolling terrain. The RWMC began disposal of INEL-generated wastes in 1952, and since 1954, wastes have been accepted from other Federal facilities. Much of the waste is buried in shallow trenches, pits, and soil vaults. Until about 1970, trenches and pits were excavated to the basalt surface, leaving no sediments between the waste and the top of the basalt. Since 1970, a layer of sediment (about 1 m) has been left between the waste and the basalt. The United States Department of Energy (DOE) has developed regulations specific to radioactive-waste disposal, including environmental standards and performance objectives. The regulation applicable to all DOE facilities is DOE Order 5820.2A (Radioactive Waste Management). An important consideration for the performance assessment of the RWMC is the long-term geomorphic stability of the site. Several investigators have identified geologic processes and events that could disrupt a radioactive waste disposal facility. Examples of these {open_quotes}geomorphic hazards{close_quotes} include changes in stream discharge, sediment load, and base level, which may result from climate change, tectonic processes, or magmatic processes. In the performance assessment, these hazards are incorporated into scenarios that may affect the future performance of the RWMC.

  5. Geologic processes in the RWMC area, Idaho National Engineering Laboratory: Implications for long term stability and soil erosion at the radioactive waste management complex

    International Nuclear Information System (INIS)

    Hackett, W.R.; Tullis, J.A.; Smith, R.P.

    1995-09-01

    The Radioactive Waste Management Complex (RWMC) is the disposal and storage facility for low-level radioactive waste at the Idaho National Engineering Laboratory (INEL). Transuranic waste and mixed wastes were also disposed at the RWMC until 1970. It is located in the southwestern part of the INEL about 80 km west of Idaho Falls, Idaho. The INEL occupies a portion of the Eastern Snake River Plain (ESRP), a low-relief, basalt, and sediment-floored basin within the northern Rocky Mountains and northeastern Basin and Range Province. It is a cool and semiarid, sagebrush steppe desert characterized by irregular, rolling terrain. The RWMC began disposal of INEL-generated wastes in 1952, and since 1954, wastes have been accepted from other Federal facilities. Much of the waste is buried in shallow trenches, pits, and soil vaults. Until about 1970, trenches and pits were excavated to the basalt surface, leaving no sediments between the waste and the top of the basalt. Since 1970, a layer of sediment (about 1 m) has been left between the waste and the basalt. The United States Department of Energy (DOE) has developed regulations specific to radioactive-waste disposal, including environmental standards and performance objectives. The regulation applicable to all DOE facilities is DOE Order 5820.2A (Radioactive Waste Management). An important consideration for the performance assessment of the RWMC is the long-term geomorphic stability of the site. Several investigators have identified geologic processes and events that could disrupt a radioactive waste disposal facility. Examples of these open-quotes geomorphic hazardsclose quotes include changes in stream discharge, sediment load, and base level, which may result from climate change, tectonic processes, or magmatic processes. In the performance assessment, these hazards are incorporated into scenarios that may affect the future performance of the RWMC

  6. In situ polymerized wood polymer composite: effect of additives and nanoclay on the thermal, mechanical properties

    Directory of Open Access Journals (Sweden)

    Rashmi R Devi

    2013-01-01

    Full Text Available This study concerns the preparation and characterization of wood polymer nanocomposites based on impregnation of styrene acrylonitrile co-polymer-nanoclay intercalating system in presence of glycidyl methacrylate (GMA, a cross linking agent, and vinyl trichloro silane (VTCS as additives into Simul (Bombex ceiba, L., a soft wood. The effect of nanoclay and VTCS on the properties of the resultant wood polymer nanocomposites (WPNC has been evaluated. FTIR spectroscopy shows the interaction among wood, polymers, GMA, nanoclay and VTCS. The penetration of polymer and nanoclay into the wood cell wall is supported by SEM study. The distribution of nanoclay in the SAN polymer matrix present within the wood cell wall has been evidenced by TEM study. TGA results show an improvement in the thermostability of the resultant composites. The inclusion of VTCS enhances the self extinguishing behaviour of the WPNC as revealed by limiting oxygen index (LOI test. Due to treatment, the resultant WPNC exhibits an improvement in all the properties like water repellancy, dimensional stability, hardness, flexural, tensile and thermal stability compared to untreated wood.

  7. In situ polymerized wood polymer composite: effect of additives and nanoclay on the thermal, mechanical properties

    Energy Technology Data Exchange (ETDEWEB)

    Devi, Rashmi R; Maji, Tarun K., E-mail: tkm@tezu.ernet.in [Department of Chemical Sciences, Tezpur University, Assam, (India)

    2013-11-01

    This study concerns the preparation and characterization of wood polymer nanocomposites based on impregnation of styrene acrylonitrile co-polymer-nanoclay intercalating system in presence of glycidyl methacrylate (GMA), a cross linking agent, and vinyl trichloro silane (VTCS) as additives into Simul (Bombex ceiba, L.), a soft wood. The effect of nanoclay and VTCS on the properties of the resultant wood polymer nanocomposites (WPNC) has been evaluated. FTIR spectroscopy shows the interaction among wood, polymers, GMA, nanoclay and VTCS. The penetration of polymer and nanoclay into the wood cell wall is supported by SEM study. The distribution of nanoclay in the SAN polymer matrix present within the wood cell wall has been evidenced by TEM study. TGA results show an improvement in the thermostability of the resultant composites. The inclusion of VTCS enhances the self extinguishing behaviour of the WPNC as revealed by limiting oxygen index (LOI) test. Due to treatment, the resultant WPNC exhibits an improvement in all the properties like water repellency, dimensional stability, hardness, flexural, tensile and thermal stability compared to untreated wood. (author)

  8. Synthesis and Characterization of Pure Copper Nanostructures Using Wood Inherent Architecture as a Natural Template

    Science.gov (United States)

    Dong, Youming; Wang, Kaili; Tan, Yi; Wang, Qingchun; Li, Jianzhang; Mark, Hughes; Zhang, Shifeng

    2018-04-01

    The inherent sophisticated structure of wood inspires researchers to use it as a natural template for synthesizing functional nanoparticles. In this study, pure copper nanoparticles were synthesized using poplar wood as a natural inexpensive and renewable template. The crystal structure and morphologies of the copper nanoparticles were characterized by X-ray diffraction and field emission scanning electron microscopy. The optical properties, antibacterial properties, and stability of the hybrid wood materials were also tested. Due to the hierarchical and anisotropic structure and electron-rich components of wood, pure copper nanoparticles with high stability were synthesized with fcc structure and uniform sizes and then assembled into corncob-like copper deposits along the wood cell lumina. The products of nanoparticles depended strongly on the initial OH- concentration. With an increase in OH- concentration, Cu2O gradually decreased and Cu remained. Due to the restrictions inherent in wood structure, the derived Cu nanoparticles showed similar grain size in spite of increased Cu2+ concentration. This combination of Cu nanostructures and wood exhibited remarkable optical and antibacterial properties.

  9. Women's work... in wood products

    Science.gov (United States)

    Janice K. Wiedenbeck

    1998-01-01

    Women have opportunities galore in the 1990s in wood products research, education, extension, consulting,manufacturing, marketing, and associations in North America. In the 1980s the same statement could not have been made.

  10. Wood and Paper Manufacturing Sectors

    Science.gov (United States)

    Find EPA regulatory information for the wood product and paper manufacturing sectors, including paper, pulp and lumber. Information includes NESHAPs and effluent guidelines for pulp and paper rulemaking, and compliance guidelines

  11. Wood-burning stoves worldwide

    DEFF Research Database (Denmark)

    Luis Teles de Carvalho, Ricardo

    were suggested to facilitate the transition to cleaner wood-burning regimes. Considering that 40% of the world population continues relying on traditional forms of wood-burning, the design and dissemination of cleaner technologies of WBSs constitute relevant strategies to mitigate global climate...... of improved stoves. In the Brazilian case study, it was observed that the kitchen concentrations of PM2.5 monitored during wood cooking events increased by more than 10 times in relation to the background levels due to the improper use and maintenance of the studied ICSs (rocket stoves). In Southern Europe...... to facilitate the transition to more intelligent modes of using WBSs by: 1st training solid-fuel users to better operate and maintain existing installations, 2nd harmonizing wood-burning regulations to address the use of seasoned fuels, certified stoves and functioning chimneys; 3rd designing applications...

  12. EFFECTS OF SOME BORON COMPOUNDS ON THE LEACHABILITY OF EUCALYPTUS (Eucalyptus camaldulensis Dehn. WOOD

    Directory of Open Access Journals (Sweden)

    Hüseyin Tan

    2003-04-01

    Full Text Available Wood preservation effectiveness of boron compounds against biological damagers and fire is well known. But these compounds are not widely used in preservation of wood because of their leachability from wood by rain water and making wood more hyroscopic than untreated wood in damp environments. Main aim of this study is; therefore, to improve the undesired leachability properties of some boron compounds by various water repellents (WRs. Aqueous solutions with polyethyleneglycole (PEG-400 of boric acid and sodium perborate were chosen as boron compounds. WRs were used as secondary treatment chemicals which were considered as dimensional stabilizer of wood and phsical bariers of boron retained at innerparts of treated wood. Results indicated that WRs were reduced leachability of boron from wood significantly (P<0.05. Boron salts applied with. PEG were more leachable than were of equeous solutions. WRs were not found effective on reducing the leachability of boron solved in PEG. Longer leaching time caused more leachant and reduction the phsical alleviation of WRs on boron leaching.

  13. Wood ash to treat sewage sludge for agricultural use

    Energy Technology Data Exchange (ETDEWEB)

    White, R.K. [Clemson Univ., SC (United States)

    1993-12-31

    About 90% of the three million tons of wood ash generated in the United States from wood burning facilities is being landfilled. Many landfills are initiated tipping fees and/or restrictions on the disposal of special wastes such as ash. The purpose of this work was to evaluate (1) the feasibility of using wood ash to stabilize sewage sludge and (2) the fertilizer and liming value of the sludge/ash mixture on plant response and soil pH. Research showed that wood ash, when mixed with sludge, will produce a pH above 12.0, which meets US EPA criteria for pathogen reduction for land application on non-direct food chain crops. Different ratios of wood ash to sludge mixtures were tested and the 1:1 ratio (by weight) was found to be optimal. Five replications of wood ash from four sources were tested for moisture content, pH and fertilizer nutrients. The pH of the ash/sludge mixture (1:1) on day one ranged from 12.4 to 13.2. In most cases the pH remained the same over a 21 day test or only dropped 0.1 to 0.3 units. Analyses of the mixtures showed that heavy metal concentrations (As, B, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, S, Se, Zn) were low. The 1:1 ash/sludge mixture had a calcium carbonate equivalency of 17%. Green house pot studies using tall fescue grass were loadings of 300 to 750 pounds per acre of TKN-N than for 500 lb/acre of 10-10-10 commercial fertilizer. Plant tissue analysis showed N, P, K, Ca, and Mg levels to be within the sufficiency range for tall fescue.

  14. Robert Williams Wood: pioneer of invisible light.

    Science.gov (United States)

    Sharma, Shruti; Sharma, Amit

    2016-03-01

    The Wood's lamp aids in the diagnosis of multiple infectious, inflammatory and neoplastic dermatologic conditions. Although the Wood's lamp has many applications, which have improved both the diagnosis and management of disease, the man credited for its invention is relatively unknown in medicine. Robert Williams Wood, a prominent physicist of the early 20th century, is credited for the invention of the Wood's lamp. Wood was the father of infrared and ultraviolet photography and made significant contributions to other areas in optics and spectroscopy. Wood's work encompassed the formative years of American Physics; he published over 200 original papers over his lifetime. A few years after the invention of the Wood's lamp for ultraviolet photography, physicians in Europe adopted the Wood's lamp for dermatologic applications. Wood's lamp remains popular in clinics globally, given its ease of use and ability to improve diagnostic precision. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Engineer: The Professional Bulletin of Army Engineers. Volume 41, May-August 2011

    Science.gov (United States)

    2011-08-01

    Company, 92d Engineer Battalion, 36th Engineer Brigade, Fort Stew - art, Georgia, U.S. Army Forces Command. Sturgis Medal: Staff Sergeant Jeremiah C...award recipients were recognized during ENFORCE 2011 at Fort Leonard Wood, Missouri. Regimental Awards Engineer 15May–August 2011 This article

  16. Regenerative engineering

    CERN Document Server

    Laurencin, Cato T

    2013-01-01

    Regenerative Engineering: The Future of Medicine Saadiq F. El-Amin III , MD , PhD; Joylene W.L. Thomas, MD ; Ugonna N. Ihekweazu, MD ; Mia D. Woods, MS; and Ashim Gupta, MSCell Biology Gloria Gronowicz, PhD and Karen Sagomonyants, DMDStem Cells and Tissue Regeneration Kristen Martins-Taylor, PhD; Xiaofang Wang, MD , PhD; Xue-Jun Li, PhD; and Ren-He Xu, MD , PhDIntroduction to Materials Science Sangamesh G. Kumbar, PhD and Cato T. Laurencin, MD , PhDBiomaterials A. Jon Goldberg, PhD and Liisa T. Kuhn, PhDIn Vitro Assessment of Cell-Biomaterial Interactions Yong Wang, PhDHost Response to Biomate

  17. Principles of Naval Engineering.

    Science.gov (United States)

    Naval Personnel Program Support Activity, Washington, DC.

    Fundamentals of shipboard machinery, equipment, and engineering plants are presented in this text prepared for engineering officers. A general description is included of the development of naval ships, ship design and construction, stability and buoyancy, and damage and casualty control. Engineering theories are explained on the background of ship…

  18. Refraction and absorption of microwaves in wood

    International Nuclear Information System (INIS)

    Ziherl, Saša; Bajc, Jurij; Čepič, Mojca

    2013-01-01

    A demonstration experiment for physics students showing the dependence of the refractive index and absorption coefficient of wood on the direction of microwaves is presented. Wood and microwaves enable study of anisotropic properties, which are typically found in crystals. Wood is used as the persuasive representative of uniaxial anisotropic materials due to its visible structure and its consequent anisotropic properties. Wood can be cut in a general direction and wooden plates a few centimetres thick with well-defined fibre orientation are easily prepared. Microwaves are used because wood is transparent for microwaves and their centimetre-scale wavelength is comparable to the wood structure. (paper)

  19. wood burns down

    Directory of Open Access Journals (Sweden)

    Vladimir Bukh

    2004-11-01

    Full Text Available To relax the local authorities and to receive the guests of high rank «with no tie» the so-called «Fisherman's House» was built at the source of Angara-river, near Lake Baikal. Vladimir Ivanov, a young architect, was noticed by his skillful performa nee of exclusive orders and became the author of this house. At the time of ferroconcrete boom the proposal to build a wooden guest house turned out to be unexpectedly to the point and was graciously approved. The economic department was entrusted to select the men good for carpenter's work, and the forestry department was entrusted to provide thick round timber. And the work started. But, as it usually happens, the workers did not take the trouble and made the first eight rims of the current timber with an inappropriate diameter.And when Pavlov insisted on demolishing the construction and replacing the logs by the logs with the necessary diameter, the building work obeyed to his will and was finished suecessfully.The architecture of the house is not the derived action of the saw and the fret-saw. It is a technology of the axe. It is natural, convincing and original. It is no use to look for the local sources in it. It grew up in the area of timber and cold winter. And this clear and efficient action kept the construction from the annoying vulgarity and provided Siberian exotics easily penetrating into one's soul, refined as it may be.One of the eminent guests said with admiration: «Even if Pavlov had created nothing more, he would have justified his professional choice with this single house.» Why not to say it as a good toast. However, this is a suitable case to add: style is an absence of style. It is a taste.After the Fisherman's House Irkutsk architects were attracted by wood. They followed the strictness in wood and, as much as they could, created a couple of successful remakes, until the cylinder logs and ... new

  20. High performance wood composites based on benzoxazine-epoxy alloys.

    Science.gov (United States)

    Jubsilp, Chanchira; Takeichi, Tsutomu; Hiziroglu, Salim; Rimdusit, Sarawut

    2008-12-01

    Wood-substituted composites from matrices based on ternary mixtures of benzoxazine, epoxy, and phenolic novolac resins (BEP resins) using woodflour (Hevea brasiliensis) as filler are developed. The results reveal that the addition of epoxy resin into benzoxazine resin can lower the liquefying temperature of the ternary systems whereas rheological characterization of the gel points indicates an evident delay of the vitrification time as epoxy content increased. The gelation of the ternary mixtures shows an Arrhenius-typed behavior and the gel time can be well predicted by an Arrhenius equation with activation energy of 35-40kJ/mol. For wood-substituted composites from highly filled BEP alloys i.e. at 70% by weight of woodflour, the reinforcing effect of the woodflour shows a substantial enhancement in the composite stiffness i.e. 8.3GPa of the filled BEP811 vs 5.9GPa of the unfilled BEP811. The relatively high flexural strength of the BEP wood composites up to 70MPa can also be obtained. The outstanding compatibility between the woodflour and the ternary matrices attributed to the modulus and thermal stability enhancement of the wood composites particularly with an increase of the polybenzoxazine fraction in the BEP alloys.

  1. Mechanical properties: wood lumber versus plastic lumber and thermoplastic composites

    Directory of Open Access Journals (Sweden)

    Bernardo Zandomenico Dias

    Full Text Available Abstract Plastic lumber and thermoplastic composites are sold as alternatives to wood products. However, many technical standards and scientific studies state that the two materials cannot be considered to have the same structural behaviour and strength. Moreover, there are many compositions of thermoplastic-based products and plenty of wood species. How different are their mechanical properties? This study compares the modulus of elasticity and the flexural, compressive, tensile and shear strengths of such materials, as well as the materials' specific mechanical properties. It analyses the properties of wood from the coniferae and dicotyledon species and those of commercialized and experimental thermoplastic-based product formulations. The data were collected from books, scientific papers and manufacturers' websites and technical data sheets, and subsequently compiled and presented in Ashby plots and bar graphs. The high values of the compressive strength and specific compressive and tensile strengths perpendicular to the grain (width direction shown by the experimental thermoplastic composites compared to wood reveal their great potential for use in compressed elements and in functions where components are compressed or tensioned perpendicularly to the grain. However, the low specific flexural modulus and high density of thermoplastic materials limit their usage in certain civil engineering and building applications.

  2. The Woods Hole Partnership Education Program (PEP) (Invited)

    Science.gov (United States)

    Jearld, A.; Liles, G.; Gutierrez, B.

    2013-12-01

    In March 2009, the Woods Hole Diversity Initiative (WHDI) launched the Partnership Education Program (PEP), a multi-institutional effort to increase diversity in the student population (and ultimately the work force) in the Woods Hole science community. PEP, a summer research internship program, is open to students of all backgrounds but is designed especially to provide opportunities for individuals from populations under-represented in science, technology, engineering, and mathematics (STEM) and who otherwise would not have had the opportunity to come to Woods Hole to study or do research. A month-long course, 'Ocean and Environmental Sciences: Global Climate Change,' sets the stage for their summer research projects. The PEP model is emerging as an effective and sustainable approach to bringing students into the STEM research community. PEP is carefully structured to provide critical support for students as they complete their undergraduate experience and prepare for careers and/or graduate school. In its first five years, PEP has brought to the Woods Hole science community more than 75 students from over 50 colleges and universities, including many that do not typically send talent into marine and/or ecological research. PEP is unusual (perhaps even unique) in that it is a collaborative initiative involving seven partner institutions. Working together, the PEP collaborative has established a critical mass of under-represented students who are now in graduate school and/or working in STEM areas.

  3. Thermopower of beech wood biocarbon

    Science.gov (United States)

    Smirnov, I. A.; Smirnov, B. I.; Orlova, T. S.; Sulkovski, Cz.; Misiorek, H.; Jezowski, A.; Muha, J.

    2011-11-01

    This paper reports on measurements of the thermopower S of high-porosity samples of beech wood biocarbon with micron-sized sap pores aligned with the tree growth direction. The measurements have been performed in the temperature range 5-300 K. The samples have been fabricated by pyrolysis of beech wood in an argon flow at different carbonization temperatures ( T carb). The thermopower S has been measured both along and across the sap pores, thus offering a possibility of assessing its anisotropy. The curves S( T carb) have revealed a noticeable increase of S for T carb biocarbons, which suggests that for T carb ˜ 1000°C they undergo a phase transition of the insulator-(at T carb 1000°C) type. The existence of this transition is attested also by the character of the temperature dependences S( T) of beech wood biocarbon samples prepared at T carb above and below 1000°C.

  4. Assessment of the wood waste resource and its position in the wood / wood-energy sector - Synthesis

    International Nuclear Information System (INIS)

    Guinard, Ludovic; Deroubaix, Gerard; Roux, Marie-Lise; Levet, Anne-Laure; Quint, Vincent

    2015-04-01

    The first objective of this study is to obtain a better knowledge of the 'wood wastes' issue, to propose a photography of the wood waste sector (productions, trades, consumptions), and then to elaborate different prospective scenarios on the use of wood waste volumes while taking into account possible evolutions on the medium or short term of the regulation and market of the wood/wood energy sector. The considered wastes come from industrial production, from the use of wood-based products, and from the end of life of products potentially containing wood. The authors present bibliographical sources and the adopted methodology, briefly describe the 'wood waste' system with its actors, and then report their assessment of wood wastes. They propose a global assessment as well as detailed assessments with respect to waste origins: wood trade and distribution, industries, craft, households and communities, building sector, public and private tertiary sector, packaging. They also address the collection and management of wood wastes by public services, and present the different types of valorisation (panel fabrication, energy, and others). They discuss exports, and then present different scenarios: a trend-based scenario, and two prospective scenarios with a priority to energetic valorisation or to material valorisation of wood wastes. These scenarios are compared

  5. Wood: a construction material for tall buildings

    Science.gov (United States)

    Wimmers, Guido

    2017-12-01

    Wood has great potential as a building material, because it is strong and lightweight, environmentally friendly and can be used in prefabricated buildings. However, only changes in building codes will make wood competitive with steel and concrete.

  6. Ergonomics and safety in secondary wood processing

    Science.gov (United States)

    Rado Gazo; James D. McGlothlin; Yuehwern, Wiedenbeck, Jan Yih; Yuehwern Yih

    2002-01-01

    The main goal of the project was to initiate a pilot program in ergonomics for the secondary wood products industry. Case studies were conducted at three Midwest secondary wood product companies in 2000 and 2001.

  7. SYNERGISTIC WOOD PRESERVATIVES FOR REPLACEMENT OF CCA

    Science.gov (United States)

    The objective of this project was to evaluate the potential synergistic combinations of environmentally-safe biocides as wood preservatives. These wood preservatives could be potential replacements for the heavy-metal based CCA.Didecyldimethylammonium chloride [DDAC] was...

  8. Wood preservatives and pressure-treated wood: considerations for historic-preservation projects

    Science.gov (United States)

    Ronald W. Anthony; Stan T. Lebow

    2015-01-01

    Wood, an abundant resource throughout most of the world, has been used as a building material for thousands of years. Many historic buildings have been built primarily of wood, and masonry and stone buildings generally have wood elements, both structural and architectural. As a biological material, wood is both remarkably complex and yet quite durable if well...

  9. Effects of wood fiber characteristics on mechanical properties of wood/polypropylene composites

    Science.gov (United States)

    Nicole M. Stark; Robert E. Rowlands

    2003-01-01

    Commercial wood flour, the most common wood-derived filler for thermoplastics, is produced in a mixture of particle sizes and generally has a lower aspect ratio than wood and other natural fibers. To understand how wood flour and fiber characteristics influence the mechanical properties of polypropylene composites, we first investigated the effect of different sizes of...

  10. Energy and exergy analysis of cookstove by using Cedrus deodara (deodar wood) and saccharum officinarum (sugar cane) waste

    Science.gov (United States)

    Chouhan, A. P. Singh; Yaseen, S.; Pruthi, A.

    2017-07-01

    Deodar (Cedrus deodara) wood collected from the Kashmir region in India. This study is focused on energy and exergy analysis of cook stove by using deodar wood, demand of a cookstove is higher in rural areas. In ancient time U-shaped and three stone cook stove was used, but they emitted greenhouse gases CO and CO2 in the environment and these toxic emissions are also dangerous for human being and the environment. Sampada model cook stove used for the analysis of energy an exergy by using water boiling test with using deodar wood and bagasse samples and a mixture of wood and bagasse also used. Wood and bagasse characterized for the ultimate, proximate, calorific value before the water boiling test of the cookstove. Results carried out that the efficiency of cook stove with deodar wood was 33.33 % and exergy calculated 2.1 % and energy efficiency and energy efficiency by using bagasse were 23.23 % and 0.43 %, respectively, and wood and bagasse mixture ratio given energy and exergy efficiencies for ratios 75:25 is the best ratio of energy production. These results indicated that deodar wood is more stable because thermal stability of wood is greater than bagasse. Deodar is a suitable source for the combustion purposes of higher energy production.

  11. Fuel wood symposium; Symposium Energieholz

    Energy Technology Data Exchange (ETDEWEB)

    Wild, C.; Wauer, A. (comps.)

    2001-07-01

    The Bavarian State Institute of Forestry (LWF) organised a 'Fuel Wood Symposium' in Freising-Weihenstephan on 17.11.2000. The purpose of this specialist conference was to give an overview of the use of biomass, especially wood, as an source of energy. (orig.) [German] Die Bayerische Landesanstalt fuer Wald und Forstwirtschaft richtete am 17.11.2000 in Freising-Weihenstephan das 'Symposium Energieholz' aus. Ziel der Fachtagung war es, einen Ueberblick ueber die energetische Nutzung von Biomasse, insbesondere Holz, zu geben. (orig.)

  12. Physical modelling of the combined effect of vegetation and wood on river morphology

    Science.gov (United States)

    Bertoldi, W.; Welber, M.; Gurnell, A. M.; Mao, L.; Comiti, F.; Tal, M.

    2015-10-01

    The research reported in this paper employs flume experiments to investigate the potential effects of living vegetation and large wood on river morphology, specifically aiming to explore how different wood input and vegetation scenarios impact channel patterns and dynamics. We used a mobile bed laboratory flume, divided into three parallel channels (1.7 m wide, 10 m long) and filled with uniform sand to reproduce braided networks subject to a series of cycles of flooding, wood input, and vegetation growth. Temporal evolution of river configuration (in terms of the braiding index), vegetation establishment and erosion, and wood deposition amount and pattern was recorded in a series of vertical images. The experiments reproduced many forms and processes that have been observed in the field, from scattered logs in unvegetated, dynamic braided channels to large wood jams associated with river bars and bends in vegetated, stable, single-thread rivers. Results showed that the inclusion of vegetation in the experiments changes wood dynamics, in terms of the quantity that is stored and the depositional patterns that develop. Vegetated banks increased channel stability, reducing lateral erosion and the number of active channels. This promoted the formation of stable wood jams, where logs accumulated continuously at the same locations during subsequent floods, reinforcing their effect on river morphology. The feasibility of studying these processes in a controlled environment opens new possibilities for disentangling the complex linkages in the biogeomorphological evolution of the fluvial system and thus for promoting improved scientific understanding.

  13. Wood Properties and Kinds; A Base Syllabus on Wood Technology.

    Science.gov (United States)

    Eastern Kentucky Univ., Richmond.

    Prepared by participants in the 1968 National Defense Education Act Institute on Wood Technology, this syllabus is one of a series of basic outlines designed to aid college level industrial arts instructors in improving and broadening the scope and content of their programs. This booklet is concerned largely with the physical composition and…

  14. Solution-state NMR analysis of hydroxymethylated resorcinol cured in the presence of crude milled-wood lignin from Acer saccharum

    Science.gov (United States)

    Daniel J. Yelle

    2017-01-01

    Resorcinol-formaldehyde adhesives can reinforce stress fractures that appear from wood surface preparation. Researchers have found that applying the resorcinol-formaldehyde prepolymer, hydroxymethylated resorcinol is thought to plasticize lignin components and stabilize stress fractures through reactions with lignin subunits and hemicelluloses in wood. In this study, a...

  15. Differential Scanning Calorimetry (DSC and Thermogravimetric Analysis (TGA of Wood polymer nanocomposites

    Directory of Open Access Journals (Sweden)

    Rahman Md. Rezaur

    2017-01-01

    Full Text Available This study evaluates the thermal property of clay dispersed Styrene-co-Glycidal Methacrylate impregnated wood polymer nanocomposite (WPNC. The WPNC was characterized by FTIR, TGA and DSC methods. FT-IR result showed that the absorbance of wave number at 1730 cm−1, increased for clay dispersed Styrene-co-Glycidyl Methacrylate wood polymer nanocomposite (ST-co-GMA-clay-WPNC. From TGA, ST-co-GMA-clay-WPNC showed better thermal stability at the temperature below 450oC. The final weights of ST-co-GMA-clay-WPNC and ST-Clay-WPNC, between 420 and 700oC, were significantly less than the raw wood. When the temperature was below 450oC, nanoclay-incorporated surface modified wood composites showed enhanced higher thermal properties compared with those without nanoclay. From DSC, the degradation enthalpy at around 360oC of ST-co-GMA-Clay-WPNC was the highest.

  16. Bioremediation of treated wood with fungi

    Science.gov (United States)

    Barbara L. Illman; Vina W. Yang

    2006-01-01

    The authors have developed technologies for fungal bioremediation of waste wood treated with oilborne or metal-based preservatives. The technologies are based on specially formulated inoculum of wood-decay fungi, obtained through strain selection to obtain preservative-tolerant fungi. This waste management approach provides a product with reduced wood volume and the...

  17. Mapping wood production in European forests

    NARCIS (Netherlands)

    Verkerk, P.J.; Levers, C.; Kuemmerle, T.; Lindner, M.; Vanbuena, R.; Verburg, P.H.; Zudin, S.

    2015-01-01

    Wood production is an important forest use, impacting a range of other ecosystem services. However, information on the spatial patterns in wood production is limited and often available only for larger administrative units. In this study, we developed high-resolution wood production maps for

  18. Wood properties affecting finish service life

    Science.gov (United States)

    R. Sam. Williams; Charles. Jourdain; George I. Daisey; Robert W. Springate

    2000-01-01

    Wood is a biological material that has widely different properties depending on species, geographic area where the tree grew, the growth conditions, size of the tree at harvest, sawing, and other manufacturing processes. Some of the more important wood properties as they relate to wood finishing are discussed, e.g., growth rate, density, knots, extractives, juvenile...

  19. Build Green: Wood Can Last for Centuries

    Science.gov (United States)

    Carol A. Clausen; Samuel V. Glass

    2012-01-01

    This report updates and revises information from the 1976 Forest Service publication by Rodney C. DeGroot, “Your Wood Can Last for Centuries.” It explains why wood decays, alerts the homeowner to conditions that can result in decay in buildings, and describes measures to prevent moisture-related damage to wood.

  20. Characteristics and availability of commercially important woods

    Science.gov (United States)

    Regis B. Miller

    1999-01-01

    Throughout history, the unique characteristics and comparative abundance of wood have made it a natural material for homes and other structures, furniture, tools, vehicles, and decorative objects. Today, for the same reasons, wood is prized for a multitude of uses. All wood is composed of cellulose, lignin, hemicelluloses, and minor amounts (5% to 10%) of extraneous...

  1. European wood-pastures in transition

    DEFF Research Database (Denmark)

    Wood-pastures are important elements of European cultural identity and have an exceptional ecological value, yet they are in decline all over Europe. The structure of wood-pastures is strongly influenced by grazing and multiple other land uses and by local and regional environmental conditions. T...... conservation policies and management approaches for wood-pastures....

  2. Wood Flour Moulding Technology: Implications for Technical ...

    African Journals Online (AJOL)

    Wood Flour Moulding Technology: Implications for Technical Education in Nigeria. ... Interest in this modern industrial practice in wood anchors around the high level of unemployment among the youths in. Nigeria. ... flour moulding technology minimizes atmospheric pollution, reduces cost of wood waste disposal and curbs, ...

  3. The wood energy; Le bois energie

    Energy Technology Data Exchange (ETDEWEB)

    Vachey, C.

    2000-05-01

    This paper is a first approach of the wood energy. It presents the wood fuels, the automatic wood boilers for the collective buildings and the different domestic uses. An estimation of the cost and the advantages and disadvantages are also presented. (A.L.B.)

  4. Sustainable wood waste management in Nigeria

    Directory of Open Access Journals (Sweden)

    Owoyemi Jacob Mayowa

    2016-09-01

    Full Text Available Wood industries produce large volumes of residues which must be utilized, marketed or properly disposed of. Heaps of wood residues are common features in wood industries throughout the year. In Nigeria, this residue is generally regarded as waste and this has led to open burning practices, dumping in water bodies or dumping in an open area which constitutes environmental pollution. Sawmills in Nigeria generated over 1,000,000 m3 of wood waste in 2010 while about 5000 m3 of waste was generated in plywood mills. Nigeria generates about 1.8 million tons of sawdust annually and 5.2 million tons of wood wastes. The impact of improper disposal of waste wood on the environment affects both the aquatic and terrestrial ecosystems. Also burning of waste wood releases greenhouse gases into the atmosphere causing various health issues. Reuse/recycling of these wood residues in Nigeria will reduce the pressure on our ever decreasing forests, reduce environmental pollution, create wealth and employment. The literature available on this subject was reviewed and this article, therefore, focuses on the various methods of wood waste disposal and its utilization in Nigerian wood industries, the effects of wood waste on the environment as well as on human health and the benefits of proper wood waste management practices.

  5. Mechanical Behaviour of the Wood Masonry

    Directory of Open Access Journals (Sweden)

    Fazia FOUCHAL

    2011-09-01

    Full Text Available In this paper we study the walls wood masonry behaviour. First, we propose a regulatory validation of the walls wood masonry behaviour subjected to vertical and horizontal loads according to Eurocode 5. Then we present the numerical application on the wall wood supported two floors level.

  6. Determination of pectin content of eucalyptus wood

    NARCIS (Netherlands)

    Coetzee, B.; Schols, H.A.; Wolfaardt, F.

    2011-01-01

    Very little is known about the occurrence of pectin in wood and it is speculated that between 10 mg g-1 and 40 mg g-1 of wood consists of pectin. The present study aimed to quantify pectin in eucalyptus wood and to determine the influence of tree species, yield potential of the site, tree age class

  7. Cone calorimeter tests of wood composites

    Science.gov (United States)

    Robert H. White; Kuma Sumathipala

    2013-01-01

    The cone calorimeter is widely used for the determination of the heat release rate (HRR) of building products and other materials. As part of an effort to increase the availability of cone calorimeter data on wood products, the U.S. Forest Products Laboratory and the American Wood Council conducted this study on composite wood products in cooperation with the Composite...

  8. Utilization of Wood Waste Mahang (Macaranga SP.) From Sawmill Industry for Making Wood Vinegar

    OpenAIRE

    Sutrisno, Lis; Sulaeman, Rudianda; Sribudiani, Evi

    2014-01-01

    Wood vinegar is the result of condensation and combustion products directly or indirectly. One of the methodes to make wood vinegar is by condensing the smoke products of incomplete combustion (pyrolysis). Materials used for the manufacture of wood vinegar is mahang wood waste from the sawmill industry in the form of sawdust, shavings and slashes. This study aims to determine how much rendement, chemical constituents of wood vinegar (phenol, total acid and pH) as well as the colors of the v...

  9. Body of Wood

    Directory of Open Access Journals (Sweden)

    Pierre Michon

    2014-12-01

    not only a defrocked friar with the guys or on the street; he donned the silk babouches when he went home too. He dispossessed himself of the Seine that rolled on before his eyes; the small girl who lived on her feet, whom he puts to death in all his books, he hardly saw her; the loveliest girls of his day, the finest too for sure, who wanted him, so that he happened to come – he dispossessed himself of them, whether he came or opted to come no more, which amounted to the same thing; no apples from Norman orchards, no trees deep in the woods, no unlaced Louise Colet, no lilies, no young laughter, no Louise Colet weeping at his door, he kissed it all off, laughed over it and kissed it off, cried about it and kissed it off, he was not there. In fact he had nothing, he was deprived of everything, since it was in his head.

  10. Durable Feedback Control System for Small Scale Wood Chip Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Korpela, T.; Bjoerkqvist, T.; Lautala, P. (Tampere Univ. of Technology, Dept. of Automation Science and Engineering, FIN-33101 Tampere (Finland)). E-mail: timo.korpela@tut.fi

    2008-10-15

    The purpose is to control wood chip combustion in an inexpensive and durable way. A control concept in order to reduce the effect of fluctuation of the fuel feed is introduced. The concept is based on temperature and lambda measurements. The main task of the control system is to set the fuel feed at a desired level after a change in the combustion conditions. Additionally, temporary fluctuations of the degree of filling of feeding screw are compensated. Test results of a 80 kW and a 200 kW commercial wood chip fired systems are introduced. The process experiments indicate that the high level control system is able to adapt to varying combustion conditions and to maintain low emission levels. Furthermore, passive means that can be exploited to stabilize the combustion are discussed. As the control concept is not dependent on the design of the combustion system, the concept is adaptable to present systems

  11. Nanoindentation size effects in wood

    Science.gov (United States)

    Joseph E. Jakes; Donald S. Stone; Charles R. Frihart

    2007-01-01

    The purpose of this work was to test some of the assumptions underlying methods currently employed to investigate nanoindentation properties of wood. We examined whether hardness and modulus depend on load. We employed a surface preparation technique that minimizes alterations of cell wall properties. Areas were determined using both (a) Oliver-Pharr method and (b) a...

  12. Adhesive bonding of wood materials

    Science.gov (United States)

    Charles B. Vick

    1999-01-01

    Adhesive bonding of wood components has played an essential role in the development and growth of the forest products industry and has been a key factor in the efficient utilization of our timber resource. The largest use of adhesives is in the construction industry. By far, the largest amounts of adhesives are used to manufacture building materials, such as plywood,...

  13. The Hygroscopic Nature of Wood,

    Science.gov (United States)

    The cell walls of wood are organized as a structural system involving filamentous microfibrils , oriented essentially in the direction of the...longitudinal axis embedded in an amorphous matrix of noncrystalline cellulose , hemicelluloses, and lignin. The molecules in the amorphous regions, primarily

  14. China: changing wood products markets

    Science.gov (United States)

    Daowei Zhang; Junchang Liu; James Granskog; Jianbang Gan

    1998-01-01

    In the 1980's, China emerged as the world's second largest importer of forest products and the second largest importer of U.S. forest products. However, U.S. wood products exports to China declined nearly 93 percent from 1988 to 1996, from >/=448 million to >/=33 million. Little is known about the reasons that caused this decline. Less is probably known...

  15. Wood and concrete polymer composites

    International Nuclear Information System (INIS)

    Singer, K.

    1974-01-01

    There are several ways to prepare and use wood and concrete polymer composites. The most important improvements in the case of concrete polymer composites are obtained for compressive and tensile strengths. The progress in this field in United States and other countries is discussed in this rview. (M.S.)

  16. Kinetic investigation of wood pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Thurner, F.; Mann, U.; Beck, S. R.

    1980-06-01

    The objective of this investigation was to determine the kinetics of the primary reactions of wood pyrolysis. A new experimental method was developed which enabled us to measure the rate of gas, tar, and char production while taking into account the temperature variations during the wood heating up. The experimental method developed did not require any sophisticated instruments. It facilitated the collection of gas, tar and residue (unreacted wood and char) as well as accurate measurement of the temperature inside the wood sample. Expressions relating the kinetic parameters to the measured variables were derived. The pyrolysis kinetics was investigated in the range of 300 to 400/sup 0/C at atmospheric pressure and under nitrogen atmosphere. Reaction temperature and mass fractions of gas, tar, and residue were measured as a function of time. Assuming first-order reactions, the kinetic parameters were determined using differential method. The measured activation energies of wood pyrolysis to gas, tar, and char were 88.6, 112.7, and 106.5 kJ/mole, respectively. These kinetic data were then used to predict the yield of the various pyrolysis products. It was found that the best prediction was obtained when an integral-mean temperature obtained from the temperature-time curve was used as reaction temperature. The pyrolysis products were analyzed to investigate the influence of the pyrolysis conditions on the composition. The gas consisted mainly of carbon dioxide, carbon monoxide, oxygen, and C/sub 3//sup +/-compounds. The gas composition depended on reaction time as well as reactor temperature. The tar analysis indicated that the tar consisted of about seven compounds. Its major compound was believed to be levoglucosan. Elemental analysis for the char showed that the carbon content increased with increasing temperature.

  17. Wood pellets : a worldwide fuel commodity

    International Nuclear Information System (INIS)

    Melin, S.

    2005-01-01

    Aspects of the wood pellet industry were discussed in this PowerPoint presentation. Details of wood pellets specifications were presented, and the wood pellet manufacturing process was outlined. An overview of research and development activities for wood pellets was presented, and issues concerning quality control were discussed. A chart of the effective calorific value of various fuels was provided. Data for wood pellet mill production in Canada, the United States and the European Union were provided, and various markets for Canadian wood pellets were evaluated. Residential sales as well as Canadian overseas exports were reviewed. Production revenues for British Columbia and Alberta were provided. Wood pellet heat and electricity production were discussed with reference to prefabricated boilers, stoves and fireplaces. Consumption rates, greenhouse gas (GHG) emissions, and fuel ratios for wood pellets and fossil fuels were compared. Price regulating policies for electricity and fossil fuels have prevented the domestic expansion of the wood pellet industry. There are currently no incentives for advanced biomass combustion to enter British Columbia markets, and this has led to the export of wood pellets. It was concluded that climate change mitigation policies will be a driving force behind market expansion for wood pellets. tabs., figs

  18. Natural radionuclides and radiocaesium contained in wood

    International Nuclear Information System (INIS)

    Mahmoud, Kamal Reyad; El-Husseiny, Fathy Ahmed; Badran, Hussein Mahmoud

    2004-01-01

    The activity concentrations of natural ( 226 Ra, 232 Th and 40 K) and anthropogenic ( 137 Cs) radioactive elements in local and imported wood samples have been investigated during the last few years. Seven local and four imported wood types were measured. The activities of the natural isotopes in both local and imported wood samples were comparable. The Chernobyl accident didn't only affect European countries through contamination of the forested but also non-wood producing countries like Egypt. A fraction of the deposited fallout radionuclides has become incorporated into wood. Most of the imported samples (∼ 83%) showed measurable concentration of 137 Cs. The average 137 Cs activity levels in local and imported wood were 0.16 and 2.75 Bq/kg dry weight, respectively. The result of this study has its importance to many other wood-importing countries. (author)

  19. Forests, woods, forest plantations

    Directory of Open Access Journals (Sweden)

    Giannini R

    2006-01-01

    Full Text Available In protected areas the forest ecosystem management is directed to define the best approaches with high protection levels from ecological, historical, anthropological and landscape point of view. The conservation purposes have to be taken in consideration to not disturb the natural and functional processes, and therefore any forest human activity has to be done. Through a detailed analysis of the relations among functionality, stability, productivity and genetic diversity, the statement of the reasons for application of close-to-nature silviculture is described and discussed. Some specific silvicultural systems are illustrated on the basis of very large quantity of data and information originated from researches carried out for long time. A major challenge facing modern silviculture is to reconcile the traditional objectives of timber production with the demand for multifunctional forest ecosystems which arises from the society. The preservation of the functionality is strictly related to the forest genetic pool which is the basis of biodiversity, as it represents the basis for adaptation and survival of species and individual.

  20. Mathematical Simulation of Temperature Profiles within Microwave Heated Wood Made for Wood-Based Nano composites

    International Nuclear Information System (INIS)

    Li, X.; He, X.; Lv, J.; Wu, Y.; Luo, Y.; Chen, H.

    2013-01-01

    High intensive microwave pretreatment is a new method to modify wood for the fabrication of wood-based nano composites. Based on the physical law on heat transfer, a mathematical model to describe the temperature profiles within wood heated by high intensive microwave was established and simulated in this research. The results showed that the temperature profiles within wood were related to microwave heating methods; The temperature inside wood firstly increased and then gradually decreased along the direction of microwave transmission when the unilateral microwave heating was applied, and the temperature difference along the thickness direction of wood was very significant; The temperature with wood firstly increased and then gradually decreased from the wood surface to interior when the bilateral microwave heating was applied. Compared with the unilateral microwave heating, bilateral microwave heating is a better microwave heating method for the more uniform wood microwave pretreatment.

  1. Intelligent Heat System – high energy efficient wood stoves with low emissions

    DEFF Research Database (Denmark)

    Illerup, Jytte Boll; Nickelsen, Joachim; Hansen, Brian Brun

    2016-01-01

    This development and demonstration project conducted by HWAM A/S and DTU Chemical Engineering has contributed to the development of an automatically controlled wood stove (HWAM IHS), which is on the market today. The new digital control system ensures optimal combustion conditions by keeping...... optimal temperatures and overall oxygen concentrations in the combustion chamber throughout a complete wood log combustion cycle. This improved performance has been verified by field tests in private homes where measurements showed significant reduced emissions and higher efficiency for the IHS stoves....... Emission measurements at the research wood stove set-up at DTU Chemical Engineering showed generally low emissions of particles, well below current standards, and high energy efficiency. The highest emissions of CO, VOC and PM were seen in the ignition phase while only a small particle peak was observed...

  2. Effects of heat treatment on some physical properties of Douglas fir (Pseudotsuga menziesii) wood

    Science.gov (United States)

    Xianjun Li; Zhiyong Cai; Qunying Mou; Yiqiang Wu; Yuan Liu

    2011-01-01

    In this study the effect of heat treatment on some physical properties of Douglas fir (Pseudotsuga menziesii) was investigated. Wood specimens were subjected to heat treatment at 160, 180, 200 and 220°C for 1, 2, 3 and 4h. The results show that heat treatment resulted in a darkened color, decreased moisture performance and increased dimensional stability of...

  3. Effect of pyrolysis on solvent extractability of toxic metals from chromated copper arsenate (CCA)-treated wood.

    Science.gov (United States)

    Kakitani, Tomo; Hata, Toshimitsu; Kajimoto, Takeshi; Imamura, Yuji

    2004-06-18

    Solvent extraction was conducted to investigate the behavior of toxic metals in chromated copper arsenate (CCA)-treated wood and its pyrolysis residue. Four kinds of solvents, along with sulfuric and phosphoric acid as mineral agents, and citric and oxalic acid as complexing agents, were used. The CCA elements from the wood treated without pyrolysis were easily extracted. However, only a small amount of CCA elements were extracted from the pyrolyzed residue, even under very low pH conditions. The toxic elements in the pyrolyzed wood showed high stabilization against the solvent extraction. Pyrolysis strongly immobilized the toxic elements in the residue. Therefore, pyrolysis is not suitable as a pretreatment.

  4. 40 kW Stirling Engine for Solid Fuel

    DEFF Research Database (Denmark)

    Carlsen, Henrik; Trærup, Jens

    1996-01-01

    been adapted to the special demands of combustion of wood chips, resulting in a large engine compared to engines for gas or liquid fuels. The engine has four-cylinders arranged in a square. The design is made as a hermetic unit, where the alternator is built into the pressurised crankcase so...

  5. Intelligent Heat System - High-Energy Efficient Wood Stoves with Low Emissions. Emissions of Gases and Particles

    DEFF Research Database (Denmark)

    Illerup, Jytte Boll; Hansen, Brian Brun; Lin, Weigang

    2015-01-01

    A collaboration project between the CHEC research Centre, at DTU Chemical Engineering, and the stove manufacturing company HWAM A/S has been established during the last years and has led to development and marketing of wood stoves (Autopilot IHS) equipped with a digital control system. The improved...... performance has been verified by field tests in private homes. The main components of an Autopilot IHS wood stove are: a modern wood stove with three separate combustion air inlets, and a control system composing of measuring devices for vital process parameters and a system of controlling valves to regulate...

  6. Change of mechanical properties of Norway Spruce wood due to degradation caused by fire retardants

    Czech Academy of Sciences Publication Activity Database

    Kloiber, Michal; Frankl, Jiří; Drdácký, Miloš; Kučerová, I.; Tippner, J.; Bryscejn, Jan

    2010-01-01

    Roč. 55, č. 4 (2010), s. 23-38 ISSN 1336-4561 Grant - others:GAČR(CZ) GA103/07/1091 Program:GA Institutional research plan: CEZ:AV0Z20710524 Keywords : wood degradation * fire retardant * mechanical properties * tensile strength * hardness Subject RIV: JN - Civil Engineering Impact factor: 0.284, year: 2010

  7. Experimental Verification of a New Tool for Wood Mechanical Resistance Measurement

    Czech Academy of Sciences Publication Activity Database

    Kloiber, Michal; Tippner, J.; Hrivnák, J.; Praus, L.

    2012-01-01

    Roč. 57, č. 3 (2012), s. 383-398 ISSN 1336-4561 R&D Projects: GA ČR(CZ) GPP105/10/P573 Institutional support: RVO:68378297 Keywords : pin * resistance * mean force * density * wood strength Subject RIV: JN - Civil Engineering Impact factor: 0.275, year: 2012

  8. Wood Products Consumption for Industrial Markets in the United States, Testing a New Research Method

    Science.gov (United States)

    Craig Adair; David B. McKeever

    2013-01-01

    In early 2012, APA-The Engineered Wood Association conducted studies of three industries: institutional furniture, motor homes, and travel trailers and campers. The survey procedure was the same as that used by APA for many years. Lists of individual manufacturers were purchased, a telephone interviewing company was hired to administer a questionnaire, and APA...

  9. Mathematical Modelling at Secondary School: The MACSI-Clongowes Wood College Experience

    Science.gov (United States)

    Charpin, J. P. F.; O'Hara, S.; Mackey, D.

    2013-01-01

    In Ireland, to encourage the study of STEM (science, technology, engineering and mathematics) subjects and particularly mathematics, the Mathematics Applications Consortium for Science and Industry (MACSI) and Clongowes Wood College (County Kildare, Ireland) organized a mathematical modelling workshop for senior cycle secondary school students.…

  10. Proceedings: 19th International Nondestructive Testing and Evaluation of Wood Symposium

    Science.gov (United States)

    Robert J. Ross; Raquel Gonçalves; Xiping Wang

    2015-01-01

    The 19th International Nondestructive Testing and Evaluation of Wood Symposium was hosted by the University of Campinas, College of Agricultural Engineering (FEAGRI/UNICAMP), and the Brazilian Association of Nondestructive Testing and Evaluation (ABENDI) in Rio de Janeiro, Brazil, on September 22–25, 2015. This Symposium was a forum for those involved in nondestructive...

  11. WOOD BIOMASS FOR ENERGY IN MONTENEGRO

    Directory of Open Access Journals (Sweden)

    Gradimir Danon

    2010-01-01

    Full Text Available Wood biomass has got its place in the energy balance of Montenegro. A little more than 6% of the total energy consumption is obtained by burning wood. Along with the appropriate state measures, it is economically and environmentally justified to expect Montenegro to more than double the utilization of the existing renewable energy sources including wood biomass, in the near future. For the purpose of achieving this goal, ‘Commercial Utilisation of the Wood Residue as a Resource for Economic Development in the North of Montenegro' project was carried out in 2007. The results of this project were included in the plan of the necessary interventions of the Government and its Agencies, associations or clusters, non-government organisations and interested enterprises. The plan was made on the basis of the wood residue at disposal and the attitude of individual subjects to produce and/or use solid bio-fuels and consists of a proposal of collection and utilisation of the wood residue for each individual district in the north of Montenegro. The basic factors of sustainability of future commercialisation of the wood residue were: availability of the wood raw material, and thereby the wood residue; the development of wood-based fuel markets, and the size of the profit.

  12. Wood energy and air quality

    International Nuclear Information System (INIS)

    2015-12-01

    This publication first recalls the main benefits of the use of wood, the first source of renewable energy in France: abundant and local resource, low CO 2 emission, competitiveness, job creation. It comments the relationship between the use of this source of energy and the compliance with air quality standards as they are notably defined by European directives, as the use of wood as heating source is one of the recommended lever to improve air quality. The publication comments emissions generated by this type of heating (mainly in the housing sector, with some critical meteorological periods). Levers for actions are discussed: fleet renewal to promote the best performing equipment, practice improvements (fuel quality, apparatus maintenance). Actions undertaken by the ADEME are briefly reviewed: support to individual equipment fleet modernisation, support to R and D, support to the sector, and information and communication

  13. Discover the benefits of residential wood heating

    International Nuclear Information System (INIS)

    2003-01-01

    This publication described how residential wood-heating systems are being used to reduce energy costs and increase home comfort. Biomass energy refers to all forms are renewable energy that is derived from plant materials. The source of fuel may include sawmills, woodworking shops, forest operations and farms. The combustion of biomass is also considered to be carbon dioxide neutral, and is not considered to be a major producer of greenhouse gases (GHG) linked to global climate change. Wood burning does, however, release air pollutants, particularly if they are incompletely burned. Incomplete combustion of wood results in dense smoke consisting of toxic gases. Natural Resources Canada helped create new safety standards and the development of the Wood Energy Technical Training Program to ensure that all types of wood-burning appliances are installed correctly and safely to reduce the risk of fire and for effective wood heating. In Canada, more than 3 million families heat with wood as a primary or secondary heating source in homes and cottages. Wood heating offers security from energy price fluctuations and electrical power failures. This paper described the benefits of fireplace inserts that can transform old fireplaces into modern heating systems. It also demonstrated how an add-on wood furnace can be installed next to oil furnaces to convert an oil-only heating system to a wood-oil combination system, thereby saving thousands of dollars in heating costs. Wood pellet stoves are another wood burning option. The fuel for the stoves is produced from dried, finely ground wood waste that is compressed into hard pellets that are loaded into a hopper. The stove can run automatically for up to 24 hours. New high-efficiency advanced fireplaces also offer an alternative heating system that can reduce heating costs while preserving Canada's limited supply of fossil fuels such as oil and gas. 13 figs

  14. North America's wood pellet sector

    Science.gov (United States)

    Henry Spelter; Daniel Toth

    2009-01-01

    The North American wood pellet sector is profiled in this paper. A small pellet industry has existed since the 1930s, but its main growth occurred in the wake of the energy crisis in the 1970s. Its current spurt is even greater, growing from is set to reach 6.2 million in 2009. Most plants are small, relying on sawmill residues for fiber and thus are limited to 100,000...

  15. Carbon Sequestration via Wood Burial

    Science.gov (United States)

    Zeng, N.

    2007-12-01

    To mitigate global climate change, a portfolio of strategies will be needed to keep the atmospheric CO2 concentration below a dangerous level. Here a carbon sequestration strategy is proposed in which forest dead wood or old trees are harvested via collection or selective cutting, then buried in trenches or stowed away in above-ground shelters. The largely anaerobic condition under a sufficiently thick layer of soil will prevent the decomposition of the buried wood. Because a large flux of CO2 is constantly being assimilated into the world's forests via photosynthesis, cutting off its return pathway to the atmosphere forms an effective carbon sink. It was estimated that the carbon sequestration potential of forest wood harvest and burial is 10GtC y-1 with an uncertainty range of 5-15 GtC y-1. Based on data from North American logging industry, the cost was crudely estimated at $50/tC, significantly lower than the cost for power plant CO2 capture with geological storage, a carbon sequestration technique currently under most serious consideration. The low cost is largely because the CO2 capture is achieved at little cost by the natural process of photosynthesis. The technique is low tech, distributed, safe and can be stopped or reversed at any time. The relatively low cost may soon be competitive enough for large-scale implementation in a world-wide carbon trading market. In tropical regions with ongoing deforestation, wood burial instead of burning will immediately reduce that portion of the anthropogenic CO2 emission.

  16. Blood parasites of wood ducks

    Science.gov (United States)

    Herman, C.M.; Knisley, J.O.; Knipling, G.D.

    1971-01-01

    Examination of blood films from wood ducks (Aix sponsa) from several northeastern states revealed Haemoproteus, Leucocytozoon, Plasmodium and a typanosome. Haemoproteus occurred in all areas sampled and birds of the year from Massachusetts demonstrated the highest incidence during the last 2 weeks in August. Leucocytozoon was most prevalent in more northern areas. P. circumflexum and a trypanosome are reported for the first time from this host.

  17. The statistical stability phenomenon

    CERN Document Server

    Gorban, Igor I

    2017-01-01

    This monograph investigates violations of statistical stability of physical events, variables, and processes and develops a new physical-mathematical theory taking into consideration such violations – the theory of hyper-random phenomena. There are five parts. The first describes the phenomenon of statistical stability and its features, and develops methods for detecting violations of statistical stability, in particular when data is limited. The second part presents several examples of real processes of different physical nature and demonstrates the violation of statistical stability over broad observation intervals. The third part outlines the mathematical foundations of the theory of hyper-random phenomena, while the fourth develops the foundations of the mathematical analysis of divergent and many-valued functions. The fifth part contains theoretical and experimental studies of statistical laws where there is violation of statistical stability. The monograph should be of particular interest to engineers...

  18. Leaching of wood ash - Laboratory and field studies; Lakning av vedaska - Laboratorie- och faeltstudier

    Energy Technology Data Exchange (ETDEWEB)

    Larsson, Per-Erik

    2012-02-15

    High forest production leads to diminishing amounts of base cations and micro nutrients in forest soils. This is due to uptake in, and harvest of, the trees. Losses can be compensated for by spreading stabilized wood ash on the forest ground, which means recycling of base cations and micro nutrients. Chemical composition of wood ash can easily be described by standard methods in the laboratory. However, this does not include the process of leaching in nature, such as which components and leaching rate for different compounds. During field conditions several factors are added, which are not available in the laboratory. After almost 10 years in the forest soils there still remains large quantities of the original product. Only 10-30 % of the wood ash products and 5 % of the lime product has been leached. In the laboratory study the leached amount was slightly larger, at the most 35 % for wood ash and 20 % for lime. Both studies indicate long time for weathering of the products in forest soils. Slower leaching rate from pellets of wood ash compared to leaching rate from crushed wood ash in the laboratory study is not verified by the field study. This indicates limited possibilities to control rates of leaching in the environment

  19. Effects of Wood Pollution on Pore-Water Sulfide Levels and Eelgrass Germination

    Science.gov (United States)

    Ekelem, C.

    2016-02-01

    Historically, sawmills released wood waste onto coastal shorelines throughout the Pacific Northwest of the USA, enriching marine sediments with organic material. The increase in organic carbon boosts the bacterial reduction of sulfate and results in the production of a toxic metabolite, hydrogen sulfide. Hydrogen sulfide is a phytotoxin and can decrease the growth and survival of eelgrass. This is a critical issue since eelgrass, Zostera marina, forms habitat for many species, stabilizes sediment, and plays a role in nutrient cycling and sediment chemistry. The objective of our study was to determine the effects of wood debris on sediment pore-water hydrogen sulfide concentrations and eelgrass germination. To test the impact of wood inputs on sulfide production and seed germination, we conducted a laboratory mesocosm experiment, adding sawdust to marine sediments and measuring the sulfide levels weekly. We subsequently planted seeds in the mesocosms and measured germination rates. Higher concentrations of sawdust led to higher levels of pore-water hydrogen sulfide and drastically slower eelgrass germination rates. Treatments with greater than 10% wood enrichment developed free sulfide concentrations of 0.815 (± 0.427) mM after 118 days, suggesting sediments with greater than 10% wood pollution may have threateningly high pore-water hydrogen sulfide levels. These results can be used to set thresholds for remediation efforts and guide seed distribution in wood polluted areas.

  20. Lab and Bench-Scale Pelletization of Torrefied Wood Chips

    DEFF Research Database (Denmark)

    Shang, Lei; Nielsen, Niels Peter K.; Stelte, Wolfgang

    2013-01-01

    content, additive addition, and the degree of torrefaction on the pelletizing properties and pellet quality, i.e., density, static friction, and pellet strength. Results were compared with pellet production using a bench-scale pelletizer. The results indicate that friction is the key factor when scaling...... up from single-pellet press to bench-scale pelletizer. Tuning moisture content or increasing the die temperature did not ease the pellet production of torrefied wood chips significantly. The addition of rapeseed oil as a lubricant reduced the static friction by half and stabilized pellet production...

  1. Effect of thermal treatments on technological properties of wood from two Eucalyptus species.

    Science.gov (United States)

    Cademartori, Pedro Henrique G; Missio, André L; Mattos, Bruno D; Gatto, Darci A

    2015-03-01

    The effect of thermal treatments on physical and mechanical properties of rose gum and Sydney blue gum wood was evaluated. Wood samples were thermally modified in a combination: pre-treatment in an autoclave (127°C - 1h) and treatment in an oven (180-240°C - 4h); and only treatment in an oven at 180-240°C for 4h. Chemical changes in the structure of woods were evaluated through infrared spectroscopy. Evaluation of physical properties was performed through mass loss, specific gravity, equilibrium moisture content and dimensional stability tests. Surface changes were analyzed through apparent contact angle technique and static bending tests were carried out to evaluate the mechanical behavior. Use of pre-treatment in autoclave affected the properties analyzed, however oven, resulted in the highest changes on wood from both species. Chemical changes were related to the degradation of hemicelluloses. Moreover, a significant decrease of hygroscopicity and mechanical strength of thermally modified woods was observed, while specific gravity did not significantly change for either of the species studied. The best results of decrease of wettability were found in low temperatures, while dimensional stability increased as a function of temperature of exposure in oven. The highest loss of mechanical strength was observed at 240°C for both species.

  2. Effect of thermal treatments on technological properties of wood from two Eucalyptus species

    Directory of Open Access Journals (Sweden)

    Pedro Henrique G. de Cademartori

    2015-03-01

    Full Text Available The effect of thermal treatments on physical and mechanical properties of rose gum and Sydney blue gum wood was evaluated. Wood samples were thermally modified in a combination: pre-treatment in an autoclave (127°C - 1h and treatment in an oven (180-240°C - 4h; and only treatment in an oven at 180-240°C for 4h. Chemical changes in the structure of woods were evaluated through infrared spectroscopy. Evaluation of physical properties was performed through mass loss, specific gravity, equilibrium moisture content and dimensional stability tests. Surface changes were analyzed through apparent contact angle technique and static bending tests were carried out to evaluate the mechanical behavior. Use of pre-treatment in autoclave affected the properties analyzed, however oven, resulted in the highest changes on wood from both species. Chemical changes were related to the degradation of hemicelluloses. Moreover, a significant decrease of hygroscopicity and mechanical strength of thermally modified woods was observed, while specific gravity did not significantly change for either of the species studied. The best results of decrease of wettability were found in low temperatures, while dimensional stability increased as a function of temperature of exposure in oven. The highest loss of mechanical strength was observed at 240°C for both species.

  3. Status of Wood Processing and Storage in Nigeria | Ohagwu ...

    African Journals Online (AJOL)

    The work showcases wood processing and storage operations in Nigeria. The importance of wood as a multipurpose biomaterial were discussed as well as its nature, characteristics, lumbering pattern and other product derived from wood. The available wood/timber in Nigeria as well as the unit operations in wood ...

  4. Chapter 02: Basic wood biology—Anatomy for identification

    Science.gov (United States)

    Alex Wiedenhoeft

    2011-01-01

    Before the topics of using a hand lens, preparing wood for observation, and understanding the characters used in wood identification can be tackled, a general introduction to the biology of wood must be undertaken. The woods in commercial trade in Central America come almost exclusively from trees, so the discussion of wood biology is restricted to trees here, though...

  5. Mechanical properties of small-scale wood laminated composite poles

    Science.gov (United States)

    Cheng Piao; Todd F. Shupe; Chung Y. Hse

    2004-01-01

    Power companies in the United States consume millions of solid wood poles every year. These poles are from high-valued trees that are becoming more expensive and less available. wood laminated composite poles (LCP) are a novel alternative to solid wood poles. LCP consists of trapezoid wood strips that are bonded by a synthetic resin. The wood strips can be made from...

  6. Shellac/nanoparticles dispersions as protective materials for wood

    Science.gov (United States)

    Weththimuni, Maduka L.; Capsoni, Doretta; Malagodi, Marco; Milanese, Chiara; Licchelli, Maurizio

    2016-12-01

    Wood is a natural material that finds numerous and widespread applications, but is subject to different decay processes. Surface coating is the most common method used to protect wood against deterioration and to improve and stabilize its distinctive appearance. Shellac is a natural resin that has been widely used as a protective material for wooden artefacts (e.g. furniture, musical instruments), due to its excellent properties. Nevertheless, diffusion of shellac-based varnishes has significantly declined during the last decades, because of some limitations such as the softness of the coating, photo-degradation, and sensitivity to alcoholic solvents and to pH variations. In the present study, different inorganic nanoparticles were dispersed into dewaxed natural shellac and the resulting materials were investigated even after application on wood specimens in order to assess variations of the coating properties. Analyses performed by a variety of experimental techniques have shown that dispersed nanoparticles do not significantly affect some distinctive and desirable features of the shellac varnish such as chromatic aspect, film-forming ability, water repellence, and adhesion. On the other hand, the obtained results suggested that some weak points of the coating, such as low hardness and poor resistance to UV-induced ageing, can be improved by adding ZrO2 and ZnO nanoparticles, respectively.

  7. Wood biomass gasification: Technology assessment and prospects in developing countries

    International Nuclear Information System (INIS)

    Salvadego, C.

    1992-05-01

    This investigation of the technical-economic feasibility of the development and use of wood biomass gasification plants to help meet the energy requirements of developing countries covers the following aspects: resource availability and production; gasification technologies and biomass gasification plant typology; plant operating, maintenance and safety requirements; the use of the biomass derived gas in internal combustion engines and boilers; and the nature of energy requirements in developing countries. The paper concludes with a progress report on biomass gasification research programs being carried out in developing countries world-wide

  8. Carbon sequestration via wood burial

    Directory of Open Access Journals (Sweden)

    Zeng Ning

    2008-01-01

    Full Text Available Abstract To mitigate global climate change, a portfolio of strategies will be needed to keep the atmospheric CO2 concentration below a dangerous level. Here a carbon sequestration strategy is proposed in which certain dead or live trees are harvested via collection or selective cutting, then buried in trenches or stowed away in above-ground shelters. The largely anaerobic condition under a sufficiently thick layer of soil will prevent the decomposition of the buried wood. Because a large flux of CO2 is constantly being assimilated into the world's forests via photosynthesis, cutting off its return pathway to the atmosphere forms an effective carbon sink. It is estimated that a sustainable long-term carbon sequestration potential for wood burial is 10 ± 5 GtC y-1, and currently about 65 GtC is on the world's forest floors in the form of coarse woody debris suitable for burial. The potential is largest in tropical forests (4.2 GtC y-1, followed by temperate (3.7 GtC y-1 and boreal forests (2.1 GtC y-1. Burying wood has other benefits including minimizing CO2 source from deforestation, extending the lifetime of reforestation carbon sink, and reducing fire danger. There are possible environmental impacts such as nutrient lock-up which nevertheless appears manageable, but other concerns and factors will likely set a limit so that only part of the full potential can be realized. Based on data from North American logging industry, the cost for wood burial is estimated to be $14/tCO2($50/tC, lower than the typical cost for power plant CO2 capture with geological storage. The cost for carbon sequestration with wood burial is low because CO2 is removed from the atmosphere by the natural process of photosynthesis at little cost. The technique is low tech, distributed, easy to monitor, safe, and reversible, thus an attractive option for large-scale implementation in a world-wide carbon market.

  9. Effect of Composite Action on the Strength of Wood Roofs

    Directory of Open Access Journals (Sweden)

    Ivan A. Campos Varela

    2015-01-01

    Full Text Available Engineering certification for the installation of solar photovoltaic modules on wood roofs is often denied because existing wood roofs do not meet current building codes. Rather than requiring expensive structural retrofits, we desire to show that many roofs are actually sufficiently strong if the effect of composite action produced by joist-sheathing interaction is considered. In a series of laboratory experiments using a limited number of two-by-four wood joists with and without sheathing panels, conventionally sheathed stud-grade joists, surprisingly, exhibited between 18% and 63% higher nominal strength than similar bare joists. To explain this strength increase, a simple model was developed to predict the strengths of the nailed partially composite sections, but the model only justifies a 1.4% to 3.8% increase in bending strength of joists with an allowable bending strength of 1000 psi. More testing is indicated to resolve this discrepancy between laboratory results and analytical modeling results. In addition to elucidating nonlinear partial composite behavior of existing roof systems, this paper shows that, with minor changes in roof framing practices, strength increases of 70% or more are achievable, compared to the strengths of conventionally sheathed joists.

  10. OPTIMIZATION OF WOOD MILLING SCHEDULE – A CASE STUDY

    Directory of Open Access Journals (Sweden)

    Emilia-Adela SALCA

    2015-12-01

    Full Text Available The paper presents the results of a case study applied to the milling process of solid wood specimens made of black alder wood (Alnus glutinosa L. Gaertn. with a view to find the optimal cutting schedule when two main criteria, such as the minimum power consumption and the best surface quality are fulfilled.The experimental work was performed with black alder wood originating from mature trees from the Buzau Valley region in Romania. All samples were processed on their longitudinal edges by straight milling with a milling cutter having glued straight plates on the vertical milling machine under different cutting schedules. An electronic device connected to the machine engine and an acquisition board were used to record and compute the power consumption during milling. Roughness measurements of the samples were performed by employing an optical profilometer. All data were processed using the regression method and variance analysis. The study revealed that best results are to be obtained in terms of cutting power and surface quality when processing with low feed speeds and light cutting depths.

  11. Power and efficiency of wood burning furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Hirsch, D.; Froment, G.; Kubala, J.F.; Chantret, A.; Renault, G.

    1982-06-01

    In 1981 an automated test rig for wood boilers was set up at the COSTIC. The special characteristics of wood combustion made it necessary to develop a computerized measuring method that enables the progress of this combustion to be followed step by step in the furnaces. After a number of preliminary adjustments, it is possible to move on to a series of tests during which the essential difficulty is to assess the wood consumption.

  12. Wood Energy Potential in Northwestern South Carolina

    Science.gov (United States)

    James W. McMinn

    1986-01-01

    The quantity of unused wood in an Ill-county area in northwestern South Carolina was projected to be more than 16 million tons annually. Wood that is unsuitable for products other than fuel amounts to nearly 9 million tons annually.The most likely energy demand by industrial plants that are good candidates for wood fuel systems is 1.5 million tons annually.Maximum...

  13. Wood's light in Microsporum canis positive patients.

    Science.gov (United States)

    Kefalidou, S; Odia, S; Gruseck, E; Schmidt, T; Ring, J; Abeck, D

    1997-12-01

    In 64 patients with culturally proven Microsporum canis infections, Wood's light examination was performed. In 30 patients (47%) the characteristic fluorescence correlated with the cultural findings, whereas in the remaining 34 patients (53%), Microsporum canis was isolated, although Wood's light examination was negative. Of the 30 positive and 34 negative cases eight patients of each group had been pre-treated. From the results presented, Wood's light examination has a poor sensitivity in cases of Microsporum canis-infections.

  14. PHYSICAL AND MECHANICAL PROPERTIES OF TORREFIED Ceiba pentandra WOOD

    Directory of Open Access Journals (Sweden)

    Ebenezer A. IYIOLA

    2016-09-01

    Full Text Available The need for improving or enhancing the performance of wood to meet the use for high economic value is a necessity. Physico-mechanical properties of torrefied Ceiba pentandra wood were investigated. Thirty nine defect-free specimens of dimensions 20mm × 20mm × 60mm (breadth × thickness x length were prepared for the determination of dimensional stability and compression test. For the evaluation of static bending strength tests, thirty nine specimens of dimensions 20mm × 20mm x 300mm were prepared. The specimens (at constant m.c. of 12% were thermally treated at temperatures of 120, 140, 160 and 180o C for 60, 90 and 120 minutes duration. The wood samples were introduced into the furnace and ramped to the temperature at which the actual heat treatment occurred. Density, Moisture content, Weight Loss, Void Volume, Water absorption, Volume swelling, Modulus of Elasticity (MOE, Modulus of Rupture (MOR, Maximum Compression Strength (MCS and Hardness of the torrefied and untreated samples were investigated. The mean values of the density showed a significant reduction as a function of treatment condition. The mean values of the moisture content of the wood samples varies 7.40% to 3.35% which is the highest reduction found in the treatment180o C for 120minutes. High weight loss was observed at 180o C for 2hrs (6.99%. The value of the volumetric swelling ranges from 7.52% to 1.39% compared to control (28.94% in 24hrs. The mean values of thermally treated samples for Modulus of Elasticity ranging from 10401 N/mm2 (180°C at 60 min to 1757N/mm2 (120°C at 90 min compared to control (MOE = 1694N/mm2 . The Modulus of Elasticity of the heat-treated samples increased rapidly as the temperature rises to 180o C for 60minutes but decreased as the time increases. It can be concluded that thermal modification improved dimensional stability and mechanical properties of wood samples

  15. Study of wood polymer combinations for various woods of Kashmir - Part I

    International Nuclear Information System (INIS)

    Mohan, H.; Rao, K.N.

    1977-01-01

    The report describes the studies conducted to upgrade inferior woods in Kashmir by the method of radiation polymerisation. The normal qualities of wood are retained and modifications brought about in unfavourable properties such as softness, dimensional instability, hygroscopicity and compressibility. Various changes in properties of wood after the modifications are discussed. It is shown that 50% of polymer content in wood considerably improves the physical and mechanical properties. (author)

  16. The use of new, aqueous chemical wood modifications to improve the durability of wood-plastic composites

    Science.gov (United States)

    Rebecca E. Ibach; Craig M. Clemons; George C. Chen

    2017-01-01

    The wood flour used in wood-plastic composites (WPCs) can biologically deteriorate and thus the overall mechanical performance of WPCs decrease when exposed to moisture and fungal decay. Protecting the wood flour by chemical modification can improve the durability of the wood in a nontoxic way so it is not harmful to the environment. WPCs were made with modified wood...

  17. Wood-energy in Europe: resources, technologies

    International Nuclear Information System (INIS)

    Defaye, S.

    1999-01-01

    A voluntaristic policy for the development of wood fuel would contribute to save energy and to protect the environment. Different strategies of development exist at the European scale as demonstrated by a recent report ordered by the French agency of environment and energy mastery (ADEME). This paper gives a synthesis of this report. It deals successively with: the European wood resources (the northern and continental forests, the mountain and bocage regions, the Mediterranean forests); the 3 main resources: forest exploitation, wood transformation, recycling of waste wood; the different economical status of wood resources; the place of wood-fuel in the economy: estimation, complementarity of industrial and energy uses; technological files and perspectives of development: collection, transport, conditioning, fuel production and supply, technologies of energy production from wood (domestic heating, collective heating, cogeneration and mixed wood-coal combustion); future markets; strategy of development: forestry and agriculture, management, producers, environmental aspects, afforestation of abandoned lands, employment...; policies of European, national and regional authorities: political and financial help, regulations and standardizations, financial helps and fiscal policy, inter-region cooperation and R and D, advice and communication; contribution of wood-fuel to the energy supply of Europe. (J.S.)

  18. Wood energy 2000; Bois energie 2000

    Energy Technology Data Exchange (ETDEWEB)

    Druette, L. [Centre Scientifique et Technique du Batiment, (CSTB), 44 - Nantes (France); Lacome, T. [AFNOR, 75 - Paris (France); Roy, C. [Agence de l' Environnement et de la Maitrise de l' Energie, ADEME, 75 - Paris (France)] [and others

    2000-07-01

    The deregulation of the Electric Market and the opening of the Green Certificate exchange market force the set up of renewable energies. The wood, which is for most of european countries an important part of renewable fuel, should see the increase of its utilization. This conference on the wood energy deals the main aspects of this energy development. The papers present the wood burning furnaces technology assessment, the wood fuel market and the standardization of the appliances in this domain. Some papers also include the consequences of the big storms of december 1999. (A.L.B.)

  19. Hillslope hydrology and stability

    Science.gov (United States)

    Lu, Ning; Godt, Jonathan

    2012-01-01

    Landslides are caused by a failure of the mechanical balance within hillslopes. This balance is governed by two coupled physical processes: hydrological or subsurface flow and stress. The stabilizing strength of hillslope materials depends on effective stress, which is diminished by rainfall. This book presents a cutting-edge quantitative approach to understanding hydro-mechanical processes across variably saturated hillslope environments and to the study and prediction of rainfall-induced landslides. Topics covered include historic synthesis of hillslope geomorphology and hydrology, total and effective stress distributions, critical reviews of shear strength of hillslope materials and different bases for stability analysis. Exercises and homework problems are provided for students to engage with the theory in practice. This is an invaluable resource for graduate students and researchers in hydrology, geomorphology, engineering geology, geotechnical engineering and geomechanics and for professionals in the fields of civil and environmental engineering and natural hazard analysis.

  20. Cable Stability

    CERN Document Server

    Bottura, L

    2014-01-01

    Superconductor stability is at the core of the design of any successful cable and magnet application. This chapter reviews the initial understanding of the stability mechanism, and reviews matters of importance for stability such as the nature and magnitude of the perturbation spectrum and the cooling mechanisms. Various stability strategies are studied, providing criteria that depend on the desired design and operating conditions.

  1. Energy wood. Part 2b: Wood pellets and pellet space-heating systems

    International Nuclear Information System (INIS)

    Nussbaumer, T.

    2002-01-01

    The paper gives an overview on pellet utilization including all relevant process steps: Potential and properties of saw dust as raw material, pellet production with drying and pelletizing, standardization of wood pellets, storage and handling of pellets, combustion of wood pellets in stoves and boilers and applications for residential heating. In comparison to other wood fuels, wood pellets show several advantages: Low water content and high heating value, high energy density, and homogeneous properties thus enabling stationary combustion conditions. However, quality control is needed to ensure constant properties of the pellets and to avoid the utilization of contaminated raw materials for the pellet production. Typical data of efficiencies and emissions of pellet stoves and boilers are given and a life cycle analysis (LCA) of wood pellets in comparison to log wood and wood chips is described. The LCA shows that wood pellets are advantageous thanks to relatively low emissions. Hence, the utilization of wood pellet is proposed as a complementary technology to the combustion of wood chips and log wood. Finally, typical fuel cost of wood pellets in Switzerland are given and compared with light fuel oil. (author)

  2. Detection of wood failure by image processing method: influence of algorithm, adhesive and wood species

    Science.gov (United States)

    Lanying Lin; Sheng He; Feng Fu; Xiping Wang

    2015-01-01

    Wood failure percentage (WFP) is an important index for evaluating the bond strength of plywood. Currently, the method used for detecting WFP is visual inspection, which lacks efficiency. In order to improve it, image processing methods are applied to wood failure detection. The present study used thresholding and K-means clustering algorithms in wood failure detection...

  3. The central role of wood biology in understanding the durability of wood-coating interactions

    Science.gov (United States)

    Alex C. Wiedenhoeft

    2007-01-01

    To design effectively for durability, one must actively and honestly assess the material properties and limitations of each of the components in the design system; wood or wood composite, and the coating. Inasmuch as wood coatings are manufactured to specified tolerances from known materials, we have control of that component of the system. Compared to manmade...

  4. Moisture Performance of wood-plastic composites reinforced with extracted and delignified wood flour

    Science.gov (United States)

    Yao Chen; Nicole M. Stark; Mandla A. Tshabalala; Jianmin Gao; Yongming Fan

    2014-01-01

    This study investigated the effect of using extracted and delignified wood flour on water sorption properties of wood–plastic composites. Wood flour (WF) extraction was performed with three solvent systems: toluene/ethanol (TE), acetone/water (AW), and hot water (HW); delignification was conducted using sodium chlorite/acetic acid solution. A 24 full-factorial...

  5. Weathering characteristics of wood plastic composites reinforced with extracted or delignified wood flour

    Science.gov (United States)

    Yao Chen; Nicole M. Stark; Mandla A. Tshabalala; Jianmin Gao; Yongming Fan

    2016-01-01

    This study investigated weathering performance of an HDPE wood plastic composite reinforced with extracted or delignified wood flour (WF). The wood flour was pre-extracted with three different solvents, toluene/ethanol (TE), acetone/water (AW), and hot water (HW), or sodium chlorite/acetic acid. The spectral properties of the composites before and after artificial...

  6. Variation in wood nutrients along a tropical soil fertility gradient.

    Science.gov (United States)

    Heineman, Katherine D; Turner, Benjamin L; Dalling, James W

    2016-07-01

    Wood contains the majority of the nutrients in tropical trees, yet controls over wood nutrient concentrations and their function are poorly understood. We measured wood nutrient concentrations in 106 tree species in 10 forest plots spanning a regional fertility gradient in Panama. For a subset of species, we quantified foliar nutrients and wood density to test whether wood nutrients scale with foliar nutrients at the species level, or wood nutrient storage increases with wood density as predicted by the wood economics spectrum. Wood nutrient concentrations varied enormously among species from fourfold in nitrogen (N) to > 30-fold in calcium (Ca), potassium (K), magnesium (Mg) and phosphorus (P). Community-weighted mean wood nutrient concentrations correlated positively with soil Ca, K, Mg and P concentrations. Wood nutrients scaled positively with leaf nutrients, supporting the hypothesis that nutrient allocation is conserved across plant organs. Wood P was most sensitive to variation in soil nutrient availability, and significant radial declines in wood P indicated that tropical trees retranslocate P as sapwood transitions to heartwood. Wood P decreased with increasing wood density, suggesting that low wood P and dense wood are traits associated with tree species persistence on low fertility soils. Substantial variation among species and communities in wood nutrient concentrations suggests that allocation of nutrients to wood, especially P, influences species distributions and nutrient dynamics in tropical forests. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  7. Effects of different durations of acid hydrolysis on the properties of starch-based wood adhesive.

    Science.gov (United States)

    Wang, Yajie; Xiong, Hanguo; Wang, Zhenjiong; Zia-Ud-Din; Chen, Lei

    2017-10-01

    In this study, the effect of different durations of acid hydrolysis on the improvement of the properties of starch-based wood adhesive was investigated through a variety of determination methods The improved properties were analyzed using the pasting properties, viscosity, shear performance in dry and wet states, fourier infrared spectrometer, dynamic time sweep, and low filed nuclear magnetic resonance spectroscopy. Starch hydrolysis improved the viscosity stability, bonding performance, and water resistance of the starch-based wood adhesive. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Cellulose-hemicellulose interaction in wood secondary cell-wall

    Science.gov (United States)

    Zhang, Ning; Li, Shi; Xiong, Liming; Hong, Yu; Chen, Youping

    2015-12-01

    The wood cell wall features a tough and relatively rigid fiber reinforced composite structure. It acts as a pressure vessel, offering protection against mechanical stress. Cellulose microfibrils, hemicellulose and amorphous lignin are the three major components of wood. The structure of secondary cell wall could be imagined as the same as reinforced concrete, in which cellulose microfibrils acts as reinforcing steel bar and hemicellulose-lignin matrices act as the concrete. Therefore, the interface between cellulose and hemicellulose/lignin plays a significant role in determine the mechanical behavior of wood secondary cell wall. To this end, we present a molecular dynamics (MD) simulation study attempting to quantify the strength of the interface between cellulose microfibrils and hemicellulose. Since hemicellulose binds with adjacent cellulose microfibrils in various patterns, the atomistic models of hemicellulose-cellulose composites with three typical binding modes, i.e. bridge, loop and random binding modes are constructed. The effect of the shape of hemicellulose chain on the strength of hemicellulose-cellulose composites under shear loadings is investigated. The contact area as well as hydrogen bonds between cellulose and hemicellulose, together with the covalent bonds in backbone of hemicellulose chain are found to be the controlling parameters which determine the strength of the interfaces in the composite system. For the bridge binding model, the effect of shear loading direction on the strength of the cellulose material is also studied. The obtained results suggest that the shear strength of wood-inspired engineering composites can be optimized through maximizing the formations of the contributing hydrogen bonds between cellulose and hemicellulose.

  9. Cellulose-hemicellulose interaction in wood secondary cell-wall

    International Nuclear Information System (INIS)

    Zhang, Ning; Li, Shi; Hong, Yu; Chen, Youping; Xiong, Liming

    2015-01-01

    The wood cell wall features a tough and relatively rigid fiber reinforced composite structure. It acts as a pressure vessel, offering protection against mechanical stress. Cellulose microfibrils, hemicellulose and amorphous lignin are the three major components of wood. The structure of secondary cell wall could be imagined as the same as reinforced concrete, in which cellulose microfibrils acts as reinforcing steel bar and hemicellulose-lignin matrices act as the concrete. Therefore, the interface between cellulose and hemicellulose/lignin plays a significant role in determine the mechanical behavior of wood secondary cell wall. To this end, we present a molecular dynamics (MD) simulation study attempting to quantify the strength of the interface between cellulose microfibrils and hemicellulose. Since hemicellulose binds with adjacent cellulose microfibrils in various patterns, the atomistic models of hemicellulose-cellulose composites with three typical binding modes, i.e. bridge, loop and random binding modes are constructed. The effect of the shape of hemicellulose chain on the strength of hemicellulose-cellulose composites under shear loadings is investigated. The contact area as well as hydrogen bonds between cellulose and hemicellulose, together with the covalent bonds in backbone of hemicellulose chain are found to be the controlling parameters which determine the strength of the interfaces in the composite system. For the bridge binding model, the effect of shear loading direction on the strength of the cellulose material is also studied. The obtained results suggest that the shear strength of wood-inspired engineering composites can be optimized through maximizing the formations of the contributing hydrogen bonds between cellulose and hemicellulose. (paper)

  10. Decay Resistance Variability of European Wood Species Thermally Modified by Industrial Process

    Directory of Open Access Journals (Sweden)

    Kevin CANDELIER

    2017-06-01

    Full Text Available Thermal modification is now considered as a new ecofriendly industrial wood modification process improving mainly the material decay resistance and its dimensional stability. Most industrial thermal treatment processes use convection heat transfer which induces sometimes heterogeneous treatment temperature propagation within the oven and lead to the heterogeneity in treatment efficiency. Thus, it is common that treatment is not completely effective on several stack boards, in a same batch. The aim of this paper was to study the decay resistance variability of various European wood species thermally modified. Thermal modifications were performed around 240°C during 4h, on about 10m3 of 27x152x2000mm3 wood planks placed in an industrial oven having a volume of 20m3 , on the following wood species: spruce, ash, beech and poplar. All of the tests concerning the decay resistance were carried out in the laboratory using untreated beech and pine woods as reference materials. An agar block test was used to determine the resistance of thermally modified woods, leached beforehand according to EN 84 standard or not, to brownrot and white-rot fungi, according to XP CEN/TS 15083-1. A large selection of treated wood samples was tested in order to estimate the variability of treatment efficiency. Thermal treatment increased the biological durability of all leached and un-leached modified wood samples, compared with native wood species. The treatment temperature of 240°C used in this study is sufficient to reach durability classes ‘‘durable’’ or ‘‘very durable’’ for the four wood species. However, the dispersion of weight loss values, due to the fungal attacks was very important and showed a large variability of the durability of wood which has been treated in a single batch. These results showed that there is a substantial need to develop process control and indicator in order to insure that the quality of treated timber is properly evaluated

  11. The Wood Anatomy of Rubiaceae tribes Anthospermeae and Paederieae

    NARCIS (Netherlands)

    Koek-Noorman, J.; Puff, Ch.

    1983-01-01

    Detailed wood anatomical descriptions are given for the genera Anthospermum, Nenax, Phyllis, Carpacoce, Coprosma, Neogaillonia, Crocyllis, Plocama and Spermadictyon, and miscellaneous wood anatomical data on the genera Normandia, Pomax, Opercularia, Leptodermis and Aitchisonia. The wood anatomical

  12. The role of wood anatomy in phylogeny reconstruction of Ericales

    NARCIS (Netherlands)

    Lens, F.; Schönenberger, J.; Baas, P.; Jansen, S.; Smets, E.

    2007-01-01

    The systematic significance of wood anatomical characters within Ericales is evaluated using separate and combined parsimony analyses including 23 wood characters and 3945 informative molecular characters. Analyses of wood features alone result in poorly resolved and conflicting topologies. However,

  13. Strength of anisotropic wood and synthetic materials. [plywood, laminated wood plastics, glass fiber reinforced plastics, polymeric film, and natural wood

    Science.gov (United States)

    Ashkenazi, Y. K.

    1981-01-01

    The possibility of using general formulas for determining the strength of different anisotropic materials is considered, and theoretical formulas are applied and confirmed by results of tests on various nonmetallic materials. Data are cited on the strength of wood, plywood, laminated wood plastics, fiber glass-reinforced plastics and directed polymer films.

  14. The Wood-Growth-and-Burial Process (WGBP) Permanent Wood Sequestration to Solve the Global Carbon Dioxide Problem

    Science.gov (United States)

    Scholz, F.; Hasse, U.

    2008-12-01

    , or/and via very slightly increased energy prices. It is a great advantage of the WGBP that it will not be competitive with the agriculture, as the areas most suitable for the process are not attractive for the growth of food or energy plants. The WGBP does not need fertilizers and irrigation, and it does not need genetically engineered plants. It is completely ecological and environmentally friendly. The WGBP can be performed at almost any place of the world, and it is not necessary to perform the process at the sites of carbon dioxide emission. The WGBP will contribute to a fair international trade. The WGBP will be equally available to all countries and societies of the world. There is no discrimination of poorer or less advanced societies. The WGBP will produce wood deposits for future generation, which once may become sources for biomass processing technologies, be it for the production of chemicals of energy. The burial sites will be saving banks of precious material. Ref.: F. Scholz, U. Hasse: ChemSusChem 1 (2008) 381-384 greifswald.de/~analytik/

  15. Manufacturing methods and magnetic characteristics of magnetic wood

    International Nuclear Information System (INIS)

    Oka, H.; Hojo, A.; Osada, H.; Namizaki, Y.; Taniuchi, H.

    2004-01-01

    The relationship between wood construction and DC magnetic characteristics for three types of magnetic wood was experimentally investigated. The results show that the magnetic characteristics of each type of magnetic wood are dependent on the magnetic materials, the density of the magnetic material and the construction of the wood. Furthermore, it was determined that the relationship between the fiber direction and the magnetic path direction of the magnetic wood influenced the wood's magnetic characteristics

  16. Social Housing: wood prefabrication techniques

    Directory of Open Access Journals (Sweden)

    Tiziana Ferrante

    2012-10-01

    Full Text Available Student housing, a particular and quite significant part of social housing, and innovation in processing and production of industrial building components made of a material (wood not adequately inquired: two fields of research that have been explored for a long time allowing here to share and compare experiences gained thus far. By a selection of samples of wooden student housing in Europe we have documented the performances of this material and we have underlined, at the same time, through what happens abroad, the need of an organic national social housing plan that can meet an unsatisfied demand and boost the construction industry during this particular stage of economic crisis.

  17. LOW COST SOLIDIFICATION/STABILIZATION TREATMENT FOR SOILS CONTAMINATED WITH DIOXIN, PCP AND CREOSOTE

    Science.gov (United States)

    The USEPA's NRMRL conducted successful treatability tests of innovative solidification/stabilization (S/S) formulations to treat soils contaminated with dioxins, pentachlorophenol (PCP), and creosote from four wood preserving sites. Formulations developed during these studies wer...

  18. Durability of wood plastic composites manufactured from recycled plastic.

    Science.gov (United States)

    Turku, Irina; Kärki, Timo; Puurtinen, Ari

    2018-03-01

    The influence of accelerated weathering, xenon-arc light and freeze-thaw cycling on wood plastic composites extruded from a recycled plastic was studied. The results showed that, in general, weathering had a stronger impact on samples made from plastic waste compared to a sample made from virgin material. After weathering, the mechanical properties, tensile and flexural, were reduced by 2-30%, depending on the plastic source. Wettability of the samples was shown to play a significant role in their stability. Chemical analysis with infrared spectroscopy and surface observation with a scan electron microscope confirmed the mechanical test results. Incorporation of carbon black retained the properties during weathering, reducing the wettability of the sample, diminishing the change of mechanical properties, and improving color stability.

  19. Preparation and characterization of waste wood post- industrial plastic reinforced with wood powder waste

    OpenAIRE

    Wallace Fernando Pedrosa de Paula; Luciana Portal da Silva

    2016-01-01

    The aim of this study is to assess the feasibility of production of composite plastic with wood waste and wood powder with improved properties.Post-industrial waste to be used as base High Density Polyethylene (HDPE) as used plastic wood, called plastic wood waste (RMP) were benefited and mixed with wood dust residues (RPM). The mixtures were prepared with different percentages (by mass) RPM (0, 10, 20, 30 and 40%) in the twin-screw extruder model TeckTrill DCT 40, with L/D: 40 and ten temper...

  20. Effect of Wood Fillers on the Viscoelastic and Thermophysical Properties of HDPE-Wood Composite

    Directory of Open Access Journals (Sweden)

    M. Tazi

    2016-01-01

    Full Text Available Wood polymer composites (WPC have well proven their applicability in several fields of the plasturgy sector, due to their aesthetics and low maintenance costs. However, for plasturgy applications, the characterization of viscoelastic behavior and thermomechanical and thermophysical properties of WPC with the temperature and wood filler contents is essential. Therefore, the processability of polymer composites made up with different percentage of wood particles needs a better understanding of materials behaviors in accordance with temperature and wood particles contents. To this end, a numerical analysis of the viscoelastic, mechanical, and thermophysical properties of composite composed of high density polyethylene (HDPE reinforced with soft wood particles is evaluated.

  1. Cold adaptation, ca2+ dependency and autolytic stability are related features in a highly active cold-adapted trypsin resistant to autoproteolysis engineered for biotechnological applications.

    Directory of Open Access Journals (Sweden)

    Alvaro Olivera-Nappa

    Full Text Available Pig trypsin is routinely used as a biotechnological tool, due to its high specificity and ability to be stored as an inactive stable zymogen. However, it is not an optimum enzyme for conditions found in wound debriding for medical uses and trypsinization processes for protein analysis and animal cell culturing, where low Ca(2+ dependency, high activity in mild conditions and easy inactivation are crucial. We isolated and thermodynamically characterized a highly active cold-adapted trypsin for medical and laboratory use that is four times more active than pig trypsin at 10(° C and at least 50% more active than pig trypsin up to 50(° C. Contrary to pig trypsin, this enzyme has a broad optimum pH between 7 and 10 and is very insensitive to Ca(2+ concentration. The enzyme is only distantly related to previously described cryophilic trypsins. We built and studied molecular structure models of this trypsin and performed molecular dynamic calculations. Key residues and structures associated with calcium dependency and cryophilicity were identified. Experiments indicated that the protein is unstable and susceptible to autoproteolysis. Correlating experimental results and structural predictions, we designed mutations to improve the resistance to autoproteolysis and conserve activity for longer periods after activation. One single mutation provided around 25 times more proteolytic stability. Due to its cryophilic nature, this trypsin is easily inactivated by mild denaturation conditions, which is ideal for controlled proteolysis processes without requiring inhibitors or dilution. We clearly show that cold adaptation, Ca(2+ dependency and autolytic stability in trypsins are related phenomena that are linked to shared structural features and evolve in a concerted fashion. Hence, both structurally and evolutionarily they cannot be interpreted and studied separately as previously done.

  2. Development of a Wood Powder Fuelled 35 kW Stirling CHP Unit

    DEFF Research Database (Denmark)

    Pålsson, M.; Carlsen, Henrik

    2003-01-01

    due to the slow burning of the fuel. To avoid sintering of ash the flame temperature in a biomass burner has to be quite low. The flame temperature can be lowered by using a high excess air rate; however this will lower system efficiency and needs a large air preheater. By using combustion gas...... recirculation (CGR) a smaller air preheater can be used, while system efficiency will increase compared with using excess air for flame cooling. In a three-year project, a wood powder fuelled Stirling engine CHP unit will be developed and run in field test. The project will use the double-acting four......For biomass fuelled CHP in sizes below 100 kW, Stirling engines are the only feasible alternative today. Using wood powder as fuel, the Stirling engine can be heated directly by the flame like when using a gaseous or liquid fuel burner. However, the combustion chamber will have to be much larger...

  3. Structural Evaluation Procedures for Heavy Wood Truss Structures

    National Research Council Canada - National Science Library

    Issa, Mohsen

    1998-01-01

    .... An evaluation procedure for wood structures differs from conventional methods used in steel, concrete, and masonry structures because, in wood construction, the allowable stresses used in design...

  4. Bacteria in decomposing wood and their interactions with wood-decay fungi.

    Science.gov (United States)

    Johnston, Sarah R; Boddy, Lynne; Weightman, Andrew J

    2016-11-01

    The fungal community within dead wood has received considerable study, but far less attention has been paid to bacteria in the same habitat. Bacteria have long been known to inhabit decomposing wood, but much remains underexplored about their identity and ecology. Bacteria within the dead wood environment must interact with wood-decay fungi, but again, very little is known about the form this takes; there are indications of both antagonistic and beneficial interactions within this fungal microbiome. Fungi are hypothesised to play an important role in shaping bacterial communities in wood, and conversely, bacteria may affect wood-decay fungi in a variety of ways. This minireview considers what is currently known about bacteria in wood and their interactions with fungi, and proposes possible associations based on examples from other habitats. It aims to identify key knowledge gaps and pressing questions for future research. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. Relationship between ecological indicators and teak wood ...

    African Journals Online (AJOL)

    Relationship between ecological indicators and teak wood characteristics in Tchorogo plantation (Togo) ... International Journal of Biological and Chemical Sciences ... Results showed that teak productivity level, which is linked to the fibre properties of teak wood varied significantly (F749,2=71.81; P<0.001 for fibre length; ...

  6. Analysis of acetylated wood by electron microscopy

    NARCIS (Netherlands)

    Sander, C.; Beckers, E.P.J.; Militz, H.; Veenendaal, van W.

    2003-01-01

    The properties of acetylated solid wood were investigated earlier, in particular the anti-shrink efficiency and the resistance against decay. This study focuses on the possible changes and damage to the wood structure due to an acetylation process leading to weight per cent gains of up to 20%.

  7. Chapter 13:Wood/Nonwood Thermoplastic Composites

    Science.gov (United States)

    Craig M. Clemons; Roger M. Rowell; David Plackett; B. Kristoffer Segerholm

    2013-01-01

    Composites made from wood, other biomass resources and polymers have existed for a long time but the nature of many of these composites has changed in recent decades. Wood-thermoset composites date to the early 1900s. "Thermosets" or thermosetting polymers are plastics that, once cured, cannot be remelted by heating. These include cured resins such as epoxies...

  8. Leonard Wood, Operational Artist or Scheming Careerist?

    Science.gov (United States)

    2012-12-06

    Enterprise, and Labour : (GP Putnam’s sons, 1899). Quoted in Lane, Armed Progressive: General Leonard Wood, 58. 79 Ibid., 58. 21 and accountable...enslave pacified Moros. “He [Wood] and other officers expressed satisfaction with the results of these devastating campaigns.”155 The criticism that...

  9. Potential for Biobased Adhesives in Wood Bonding

    Science.gov (United States)

    Charles R. Frihart

    2016-01-01

    There has been a resurgence of interest and research on using bio-based materials as wood adhesives; however, they have achieved only limited market acceptance. To better understand this low level of replacement, it is important to understand why adhesives work or fail in moisture durability tests. A holistic model for wood adhesives has been developed that clarifies...

  10. Micromechanical measurement of wood substructure properties.

    Science.gov (United States)

    David E. Kretschmann; Troy W. Schmidt; Roderic S. Lakes; Steven M. Cramer

    2002-01-01

    The annual rings of softwoods are visually obvious and represent cylindrical layers of primarily cellulosic material that possess significantly different properties. For simplicity, wood construction products are designed assuming a material homogeneity that does not exist. As rapidly grown plantation trees are used for wood products, fewer rings are contained in an...

  11. Use of nanofillers in wood coatings

    DEFF Research Database (Denmark)

    Nikolic, Miroslav; Lawther, John Mark; Sanadi, Anand Ramesh

    2015-01-01

    Wood has been used for thousands of years and remains an important material in the construction industry, most often protected with coatings. Development of nanotechnology allows further improvements or new performance properties to be achieved in wood coatings. Increased UV protection...

  12. The market for wood picnic structures.

    Science.gov (United States)

    Jerry A. Sesco

    1969-01-01

    Most of the picnic structures in six north-central states studied were constructed of wood. Service life of structure varied greatly. Vandalism and decay were the major reasons for repairing and replacing picnic tables. More than half the tables were made by the recreation agencies themselves. These results describe a market that existing and potential wood...

  13. Wood decay and the cleanup crew

    Science.gov (United States)

    Kevin T. Smith; Jessie A. Glaeser

    2017-01-01

    Arborists are encouraged to recognize the wood-decay process as an important factor in tree health and public safety. Technical experts who develop training materials to recognize wood-decay processes in living trees are frequently forest pathologists. Much of the history of forest pathology was to support production of sound, high-quality timber. That heritage is...

  14. Wood as a sustainable building material

    Science.gov (United States)

    Robert H. Falk

    2010-01-01

    Few building materials possess the environmental benefits of wood. It is not only our most widely used building material but also one with characteristics that make it suitable for a wide range of applications. As described in the many chapters of this handbook, efficient, durable, and useful wood products produced from trees can range from a minimally processed log at...

  15. Successful approaches to recycling urban wood waste

    Science.gov (United States)

    Solid Waste Association of North America

    2002-01-01

    This report presents eight case studies of successful urban wood waste recycling projects and businesses. These studies document the success of recovered products such as lumber and lumber products, mulch, boiler fuel, and alternative cover for landfills. Overall, wood waste accounts for about 17% of the total waste received at municipal solid waste landfills in the...

  16. Factors influencing wood mobilization in streams

    Science.gov (United States)

    Merten, Eric; Finlay, Jacques; Johnson, Lucinda; Newman, Raymond; Stefan, Heinz; Vondracek, Bruce

    2010-10-01

    Natural pieces of wood provide a variety of ecosystem functions in streams including habitat, organic matter retention, increased hyporheic exchange and transient storage, and enhanced hydraulic and geomorphic heterogeneity. Wood mobilization is a critical process in determining the residence time of wood. We documented the characteristics and locations of 865 natural wood pieces (>0.05 m in diameter for a portion >1 m in length) in nine streams along the north shore of Lake Superior in Minnesota. We determined the locations of the pieces again after an overbank stormflow event to determine the factors that influenced mobilization of stationary wood pieces in natural streams. Seven of 11 potential predictor variables were identified with multiple logistic regression as significant to mobilization: burial, effective depth, ratio of piece length to effective stream width (length ratio), bracing, rootwad presence, downstream force ratio, and draft ratio. The final model (P r2 = 0.39) indicated that wood mobilization under natural conditions is a complex function of both mechanical factors (burial, length ratio, bracing, rootwad presence, draft ratio) and hydraulic factors (effective depth, downstream force ratio). If stable pieces are a goal for stream management then features such as partial burial, low effective depth, high length relative to channel width, bracing against other objects (e.g., stream banks, trees, rocks, or larger wood pieces), and rootwads are desirable. Using the model equation from this study, stewards of natural resources can better manage in-stream wood for the benefit of stream ecosystems.

  17. Wood energy markets, 2011-2012

    Science.gov (United States)

    Francisco Aguilar; Rens Hartkamp; Warren Mabee; Kenneth Skog

    2012-01-01

    To celebrate the 2012 International Year of Sustainable Energy for All, in this chapter we consider in some depth the sustainability of wood energy. To do so, we evaluate the traditional economic, environmental and social dimensions of the sustainability concept. We also address how public policy has influenced wood energy sustainability across the UNECE region.

  18. Chapter 01: Wood identification and pattern recognition

    Science.gov (United States)

    Alex Wiedenhoeft

    2011-01-01

    Wood identification is a combination of art and science. Although the bulk of this manual focuses on the scientific characteristics used to make accurate field identifications of wood, the contribution of the artistic component to the identification process should be neither overlooked nor understated. Though the accumulation of scientific knowledge and experience is...

  19. Bioremediation of treated wood with bacteria

    Science.gov (United States)

    Carol A. Clausen

    2006-01-01

    This chapter reviews prior research in the field of bacterial bioremediation for wood treated with oilborne and inorganic preservatives. Current state of the art is summarized along with potential benefits and pitfalls of a pilot-scale bioremediation process for CCA-treated waste wood.

  20. Radial wood Allocation in Schizolobium Parahyba

    Science.gov (United States)

    G. Bruce Williamson; Michael C. Wiemann; James P. Geaghan

    2012-01-01

    The diversity of tropical trees has captivated botanists for centuries. Woods of difterent species, not only differ in appearance, but also in functional traits-density, porosity and strength-characteristics that relate to various plant functions such as support and conduction. The specific gravity (SG) of wood is a species' trait that integrates mechanical...