Gamma-Ray Pulsars: Beaming Evolution, Statistics, and Unidentified EGRET Sources

Science.gov (United States)

Yadigaroglu, I.-A.; Romani, Roger W.

1995-08-01

We compute the variation of the beaming fraction with the efficiency of high-energy γ-ray production in the outer gap pulsar model of Romani and Yadigaroglu. This allows us to correct the fluxes observed for pulsars in the EGRET band and to derive a simple estimate of the variation of efficiency with age. Integration of this model over the population of young neutron stars gives the expected number of γ-ray pulsars along with their distributions in age and distance. This model also shows that many of the unidentified EGRET plane sources should be pulsars and predicts the γ-ray fluxes of known radio pulsars. The contribution of unresolved pulsars to the background flux in the EGRET band is found to be ˜5%.

Optimal foraging of little egrets and their prey in a foraging game in a patchy environment.

Science.gov (United States)

Katz, M W; Abramsky, Z; Kotler, B P; Rosenzweig, M L; Alteshtein, O; Vasserman, G

2013-03-01

We explored the behavioral game between a predator, the little egret (Egretta garzetta), and a prey, the common goldfish (Carassius auratus), in a laboratory theater containing three fish pools. We tested the hypotheses that the egrets maximize their total capture success by responding to the fish's antipredatory behavior and that the behaviors of both players respond adaptively to the density distribution of fish among the pools. One experiment presented egrets with 15 fish per pool. The second experiment used a heterogeneous environment: pools 1, 2, and 3 had 10, 15, and 20 fish, respectively. Within each pool, fish could move between a safe, covered microhabitat and a risky, open microhabitat. Only the risky habitat had food, so fish were trading off food and safety by allocating the time spent in the two habitats. Egrets spent more total time in pools with more fish and returned to them sooner. Egrets maximized the number of fish they captured by following the matching rule of the ideal free distribution. The fish used the risky but productive habitat 65% of the time during experiments without egrets, but only 9% during experiments with 15 fish and egrets present somewhere in the theater. In addition, with egrets present, fish fine-tuned their behavior by reducing their use of the risky habitat as the egrets increased the frequency of their visits.

Constraints on Galactic populations from the unidentified EGRET sources

International Nuclear Information System (INIS)

Siegal-Gaskins, Jennifer M.; Pavlidou, Vasiliki; Brown, Carolyn; Olinto, Angela V.; Fields, Brian D.

2007-01-01

A significant fraction of the sources in the third EGRET catalog have not yet been identified with a low-energy counterpart. We evaluate the plausibility of a Galactic population accounting for some or all of the unidentified EGRET sources by making the simple assumption that galaxies similar to the Milky Way host comparable populations of gamma-ray emitters. Rather than focusing on the properties of a specific candidate emitter, we constrain the abundance and spatial distribution of proposed Galactic populations. We find that it is highly improbable that the unidentified EGRET sources contain more than a handful of members of a Galactic halo population, but that current observations are consistent with all of these sources being Galactic objects if they reside entirely in the disk and bulge. We discuss the additional constraints and new insights into the nature of Galactic gamma-ray emitting populations that GLAST is expected to provide

The nature of the EGRET source 3EG J1621+8203

International Nuclear Information System (INIS)

Mukherjee, R.; Stern, D.; Halpern, J.; Mirabal, N.; Gotthelf, E.V.

2001-01-01

We present broad-band observations of 3EG J1621+8203 in an effort to understand the nature of this source. We have examined X-ray images of the field from the ROSAT PSPC, ROSAT HRI, and ASCA GIS to search for a possible counterpart to the EGRET source. We find several faint X-ray point sources in the gamma-ray error circle. Preliminary analysis indicates that most of the point sources correspond to stars or to faint radio sources. Of the nearly 40% identified sources in the 3EG Catalog, the vast majority are blazars, but there is no blazer candidate in the error circle of 3EG J1621+8203. Of the notable objects in the EGRET error circle, one is the bright FR I radio galaxy NGC 6251 at a redshift of 0.0249. If NGC 6251 is the counterpart to the EGRET source 3EG J1621+8203, then it would be the second radio galaxy to be detected by EGRET. The first was Centaurus A. Cen A provided the first clear evidence of the detection above 100 MeV of an AGN with a large-inclination jet. If the identification with NGC 6251 is correct, the apparent gamma-ray luminosity of 3EG J1621+8203 is lower than that of other EGRET blazars; just as in the case of Cen A

Feasibility for EGRET detection of antimatter concentrations in the universe

Science.gov (United States)

Hartman, R. C.

1990-01-01

Although the Grand Unified Theories of elementary particle dynamics have to some extent reduced the aesthetic attraction of matter-antimatter symmetry in the Universe, the idea is still not ruled out. Although first introduced by Alfven (1965), most of the theoretical development related to gamma-ray astronomy was carried out by Stecker, who has proposed (Stecker, Morgan, and Bredekamp, 1971) matter-antimatter annihilation extending back to large redshifts as a possible explanation of the apparently extragalactic diffuse gamma radiation. Other candidate explanations were also proposed, such as superposition of extragalactic discrete sources. Clearly, the existence of significant amounts of antimatter in the universe would be of great cosmological importance; its detection, however, is not simple. Since the photon is its own antiparticle, it carries no signature identifying whether it originated in a matter or an antimatter process; even aggregates of photons (spectra) are expected to be identical from matter and antimatter processes. The only likely indicator of the presence of concentrations of antimatter is evidence of its annihilation with normal matter, assuming there is some region of contact or overlap. The EGRET (Energetic Gamma-Ray Experimental Telescope) on the Gamma Ray Observatory, with a substantial increase in sensitivity compared with earlier high energy gamma ray telescopes, may be able to address this issue. The feasibility of using EGRET in such a search for antimatter annihilation in the Universe is considered.

Feasibility for EGRET detection of antimatter concentrations in the universe

International Nuclear Information System (INIS)

Hartman, R.C.

1990-01-01

Although the Grand Unified Theories of elementary particle dynamics have to some extent reduced the aesthetic attraction of matter-antimatter symmetry in the Universe, the idea is still not ruled out. Although first introduced by Alfven (1965), most of the theoretical development related to gamma-ray astronomy was carried out by Stecker, who has proposed (Stecker, Morgan, and Bredekamp, 1971) matter-antimatter annihilation extending back to large redshifts as a possible explanation of the apparently extragalactic diffuse gamma radiation. Other candidate explanations were also proposed, such as superposition of extragalactic discrete sources. Clearly, the existence of significant amounts of antimatter in the universe would be of great cosmological importance; its detection, however, is not simple. Since the photon is its own antiparticle, it carries no signature identifying whether it originated in a matter or an antimatter process; even aggregates of photons (spectra) are expected to be identical from matter and antimatter processes. The only likely indicator of the presence of concentrations of antimatter is evidence of its annihilation with normal matter, assuming there is some region of contact or overlap. The EGRET (Energetic Gamma-Ray Experimental Telescope) on the Gamma Ray Observatory, with a substantial increase in sensitivity compared with earlier high energy gamma ray telescopes, may be able to address this issue. The feasibility of using EGRET in such a search for antimatter annihilation in the Universe is considered

Greatly reduced emission of greenhouse gases from the wood-processing industry

International Nuclear Information System (INIS)

2004-01-01

The strong support for biomass energy in the Norwegian wood-processing industry during the last 10-15 years has contributed greatly to a considerable reduction of the emission of greenhouse gases. The potential for further reductions is primarily linked with the use of oil and involves only a few works. Oil can be replaced by other fuels, and process-technical improvements can reduce the emissions. According to prognoses, emissions will go on decreasing until 2007, when the total emission of greenhouse gases from the wood-processing industry will be about 13 per cent less than in 1998. Carbon dioxide (CO 2 ) amounts to 90 per cent of the total emission, the remaining parts being methane (CH 4 ) from landfills and dumps, and small amounts of N 2 O

Naturally occurring secondary nutritional hyperparathyroidism in cattle egrets (Bubulcus ibis) from central Texas.

Science.gov (United States)

Phalen, David N; Drew, Mark L; Contreras, Cindy; Roset, Kimberly; Mora, Miguel

2005-04-01

Naturally occurring secondary nutritional hyperparathyroidism is described in the nestlings of two colonies of cattle egrets (Bubulcus ibis) from Central Texas (Bryan and San Antonio, Texas, USA). Nestlings from a third colony (Waco, Texas, USA) were collected in a subsequent year for comparison. Birds from the first two colonies consistently had severe osteopenia and associated curving deformities and folding fractures of their long bones. These birds also had reduced bone ash, increased osteoclasia, a marked decrease in osteoblast activity, variable lengthening and shortening of the hypertrophic zone of the epiphyseal cartilage, decreased and disorganized formation of new bone, and a marked hypertrophy and hyperplasia of the parathyroid glands as compared to birds collected from the third colony. Fibrous osteodystrophy was found in all of the birds from San Antonio and Bryan. Evidence of moderate to severe calcium deficiency was also identified in 33% of the cattle egrets collected from Waco. Gut contents of affected chicks contained predominately grasshoppers and crickets; vertebrate prey items were absent from the Bryan birds. Grasshoppers and crickets collected from fields frequented by the adult egrets in 1994 had 0.12-0.28% calcium and 0.76-0.81% phosphorus. Pooled grasshoppers and crickets collected during a subsequent wet early spring averaged 0.24% calcium and 0.65% phosphorus. Although the phosphorus content of the insect prey was adequate for growth, calcium was approximately one-third the minimum calcium requirement needed for growth for other species of birds. It was postulated that cattle egrets breeding in Central Texas have expanded their range into habitat that contains less vertebrate prey, and as a result, many nestling egrets are being fed diets that contain suboptimal calcium. Therefore, in years where vertebrate prey is scarce and forage for insect prey is reduced in calcium, nestling egrets are at risk for developing secondary nutritional

Naturally occurring secondary nutritional hyperparathyroidism in cattle egrets (Bubulcus ibis) from Central Texas

Science.gov (United States)

Phalen, D.N.; Drew, M.L.; Contreras, C.; Roset, K.; Mora, M.

2005-01-01

Naturally occurring secondary nutritional hyperparathyroidism is described in the nestlings of two colonies of cattle egrets (Bubulcus ibis) from Central Texas (Bryan and San Antonio, Texas, USA). Nestlings from a third colony (Waco, Texas, USA) were collected in a subsequent year for comparison. Birds from the first two colonies consistently had severe osteopenia and associated curving deformities and folding fractures of their long bones. These birds also had reduced bone ash, increased osteoclasia, a marked decrease in osteoblast activity, variable lengthening and shortening of the hypertrophic zone of the epiphyseal cartilage, decreased and disorganized formation of new bone, and a marked hypertrophy and hyperplasia of the parathyroid glands as compared to birds collected from the third colony. Fibrous osteodystrophy was found in all of the birds from San Antonio and Bryan. Evidence of moderate to severe calcium deficiency was also identified in 33% of the cattle egrets collected from Waco. Gut contents of affected chicks contained predominately grasshoppers and crickets; vertebrate prey items were absent from the Bryan birds. Grasshoppers and crickets collected from fields frequented by the adult egrets in 1994 had 0.12-0.28% calcium and 0.76-0.81% phosphorus. Pooled grasshoppers and crickets collected during a subsequent wet early spring averaged 0.24% calcium and 0.65% phosphorus. Although the phosphorus content of the insect prey was adequate for growth, calcium was approximately one-third the minimum calcium requirement needed for growth for other species of birds. It was postulated that cattle egrets breeding in Central Texas have expanded their range into habitat that contains less vertebrate prey, and as a result, many nestling egrets are being fed diets that contain suboptimal calcium. Therefore, in years where vertebrate prey is scarce and forage for insect prey is reduced in calcium, nestling egrets are at risk for developing secondary nutritional

Unidentified EGRET sources and their possible Fermi counterparts

International Nuclear Information System (INIS)

Lyapin, A R; Arkhangelskaja, I V; Larin, D S

2017-01-01

Unidentified EGRET sources from 3EG catalog have been analyzed. Preliminary data analysis has shown at least 23 of these sources coincide with those in 3FGL Fermi catalogue within 1, 2 and 3 sigma error intervals of the coordinates and fluxes. Their properties are discussed in the presented work. Even 3-sigma difference allows supposing sources similarity because of more than 3-sigma distinctions in values of fluxes between identified EGRET sources and their Fermi counterparts. For instance, the coincidence between 3EG J1255-0549 and 3FGL J1256.1-0547 was reported in Fermi catalogues 1FGL, 2FGL, 3FGL. However, these sources fluxes (in units of 10 −8 photons × cm −2 × s −1 ) in the energy band E > 100 MeV were 179.7 ± 6.7 (3EG), 44.711 ± 0.724 (3FGL), 53.611 ± 0.997 (2FGL) and 67.939 ± 1.861 (1FGL). Such effect was observed for sufficient portion of identified EGRET sources. It could cause by troubles of particles identification by Fermi/LAT trigger system. Very often charged particles recognized as gamma-quanta because of wrong backsplash analysis. Nevertheless, gammas counts as charged particles due analogous reason and rejected during ground data processing. For example, it appears as geomagnetic modulation presence on gamma-quanta count rate latitudinal profiles in energy band E > 20 MeV. (paper)

A Search for EGRET/Radio Pulsars in the ETA Carina Region

Science.gov (United States)

2002-01-01

Our analysis of EGRET data for the radio pulsar PSR B1046-58, which lies it the Eta Carina region of the Galaxy, was highly successful, resulting in the discovery of strong evidence for gamma-ray pulsations from this source. This work was published in the Astrophysical Journal. Additional support for the association was published in a companion paper in which an analysis of the X-ray counterpart to PSR B1046-58 was done, and we showed that it was the only possible counterpart to the gamma ray source within the EGRET error box.

WOOD CELLULAR DENDROCLIMATOLOGY: TESTING NEW PROXIES IN GREAT BASIN BRISTLECONE PINE

Directory of Open Access Journals (Sweden)

Emanuele Ziaco

2016-10-01

Full Text Available Dendroclimatic proxies can be generated from the analysis of wood cellular structures, allowing for a more complete understanding of the physiological mechanisms that control the climatic response of tree species. Century-long (1870-2013 time series of anatomical parameters were developed for Great Basin bristlecone pine (Pinus longaeva D.K. Bailey by capturing strongly contrasted microscopic images through a Confocal Laser Scanning Microscope. Environmental information embedded in wood anatomical series was analyzed in comparison with ring-width series using measures of empirical signal strength. Response functions were calculated against monthly climatic variables to evaluate climate sensitivity of cellular features (e.g. lumen area; lumen diameter for the period 1950-2013. Calibration-verification tests were used to determine the potential to generate long climate reconstructions from these anatomical proxies. A total of eight tree-ring parameters (two ring-width and six chronologies of xylem anatomical parameters were analyzed. Synchronous variability among samples varied among tree-ring parameters, usually decreasing from ring width to anatomical features. Cellular parameters linked to plant hydraulic performance (e.g. tracheid lumen area and radial lumen diameter showed empirical signal strength similar to ring-width series, while noise was predominant in chronologies of lumen tangential width and cell-wall thickness. Climatic signals were different between anatomical and ring-width chronologies, revealing a positive and temporally stable correlation of tracheid size (i.e. lumen and cell diameter with monthly (i.e. March and seasonal precipitation. In particular, tracheid lumen diameter emerged as a reliable moisture indicator and was then used to reconstruct total March-August precipitation from 1870 to 2013. Wood anatomy holds great potential to refine and expand dendroclimatic records by allowing estimates of plant physiological

Isolation of Salmonella spp. in cattle egrets (Bubulcus ibis) from Fernando de Noronha Archipelago, Brazil.

Science.gov (United States)

Silva, Marcio A; Fernandes, Érika F S T; Santana, Sandra C; Marvulo, Maria Fernanda V; Barros, Mércia R; Vilela, Sineide M O; Reis, Eliane M F; Mota, Rinaldo A; Silva, Jean C R

2018-03-03

The growth of the population of cattle egrets (Bubulcus ibis) in the archipelago of Fernando de Noronha constitutes a threat to public health and biological diversity because of their competition with and predation on native species and the possibility of transmission of pathogens to human beings, livestock and native wildlife. The aim here was to search for, isolate and identify serovars of Salmonella in clinically healthy local cattle egrets. Cloacal swabs were obtained from 456 clinically healthy cattle egrets of both sexes and a variety of ages. The swabs were divided into 51 pools. Six of these (11.7%) presented four serovars of Salmonella enterica subspecies enterica: Salmonella serovar Typhimurium; Salmonella serovar Newport; Salmonella serovar Duisburg; and Salmonella serovar Zega. One sample was identified as S. enterica subspecies enterica O16:y:-. Results in this study suggest that cattle egrets may be reservoirs of this agent on Fernando de Noronha and represent a risk to public health and biological diversity. Copyright © 2018. Published by Elsevier Editora Ltda.

Egret observations of the extragalactic gamma-ray emission

DEFF Research Database (Denmark)

Sreekumar, P.; Bertsch, D.L.; Dingus, B.L.

1998-01-01

The all-sky survey in high-energy gamma rays (E > 30 MeV) carried out by EGRET aboard the Compton Gamma Ray Observatory provides a unique opportunity to examine in detail the diffuse gamma-ray emission. The observed diffuse emission has a Galactic component arising from cosmic-ray interactions wi...

POPULATION DYNAMICS OF THE CATTLE EGRET Percy ...

African Journals Online (AJOL)

Egrets first breed at two years of age, and that mortality- rates of 37 and 25 per cent apply to first-year and older birds respectively, then, it will be necessary for each pair of breeders, if all second-year and older birds breed once a year, to raise an average of 1,1 young to fledging to replace the number of adults dying that ...

Calibration and adjustment of the EGRET coincidence/time-of-flight system

International Nuclear Information System (INIS)

Hunter, S.D.

1991-01-01

The coincidence/time-of-flight system of the energetic gamma ray experiment telescope (EGRET) on NASA's Gamma Ray Observatory (GRO) consists of two layers of sixteen scintillator tiles. These tiles are paired into 96 coincidence telescopes. Valid coincidence and time-of-flight values (indicating downward moving particles) from one of these telescopes are two of the requirements for an EGRET event trigger. To maximize up-down discrimination, variations in the mean timing value of the telescopes must be minimized. The timing values of the 96 telescopes are not independent, hence they cannot be individually adjusted to calibrate the system. An iterative approach was devised to determine adjustments to the length of the photomultiplier signal cables. These adjustments were made directly in units of time using a time domain reflectometry technique, by timing the reflection of a fast pulse from the unterminated end of eable, and observing the charge in signal propagation time as the length of the cable was shortened. Two constant fraction discriminators, a time-to-amplitude converter and a pulse height analyzer were used for these measurements. Using this direct time measuring approach, the timing values for the 96 EGRET coincidence/time-of-flight telescopes were adjusted with an FWHM variation of less than 450 ps (± 1 TOF timing channel). (orig.)

EGRET Unidentified Source Radio Observations and Performance of Receiver Gain Calibration

International Nuclear Information System (INIS)

Niinuma, Kotaro; Asuma, Kuniyuki; Kuniyoshi, Masaya; Matsumura, Nobuo; Takefuji, Kazuhiro; Kida, Sumiko; Takeuchi, Akihiko; Ichikawa, Hajime; Sawano, Akihiro; Yoshimura, Naoya; Suzuki, Shigehiro; Nakamura, Ryosuke; Nakayama, Yu; Daishido, Tsuneaki

2006-01-01

Last year, we have developed the receiver gain calibration system by using Johnson-Nyquist noise, for accuracy flux measurement, because we have been starting radio identification program of transient radio sources, blazars and radio counterpart of The Energetic Gamma Ray Experiment Telescope (EGRET) unidentified γ-ray sources in Waseda Nasu Pulsar Observatory. It is shown that there are a few low correlation data between receiver gain and ambient temperature around receiver for anything troubles of receiver, because we can detect gain and ambient temperature through a day by developed system. Estimated fluctuations of daily data of steady sources decrease by removing low correlation data before analysing. As the result of our analysis by using above system, radio counterpart of EGRET identified source showed fading light-curve for a week

Maximum entropy analysis of EGRET data

DEFF Research Database (Denmark)

Pohl, M.; Strong, A.W.

1997-01-01

EGRET data are usually analysed on the basis of the Maximum-Likelihood method \\cite{ma96} in a search for point sources in excess to a model for the background radiation (e.g. \\cite{hu97}). This method depends strongly on the quality of the background model, and thus may have high systematic unce...... uncertainties in region of strong and uncertain background like the Galactic Center region. Here we show images of such regions obtained by the quantified Maximum-Entropy method. We also discuss a possible further use of MEM in the analysis of problematic regions of the sky....

Environmentally acquired lead, cadmium, and manganese in the cattle egret, Bubulcus ibis, and the laughing gull, Larus atricilla

Energy Technology Data Exchange (ETDEWEB)

Hulse, M; Mahoney, J S; Schroder, G D; Hacker, C S; Pier, S M

1980-01-01

Concentrations of lead, cadmium, and manganese in the tissues of cattle egrets and laughing gulls gathered from the Galveston Bay region of Texas were compared to determine if different patterns of accumulation exist. Lead, cadmium, and manganese levels in these species were within the range reported for other bird species. Lead levels in bones were comparable, but gulls had more lead in brain, liver, and kidney tissues than egrets had, which suggested a higher rate of accumulation or exposure. Because of their high abundance and comparable positions in the estuarine and terrestrial food webs, cattle egrets and laughing gulls may serve as convenient biological indicators to monitor potentially toxic substances in these ecosystems. (29 references, 7 tables)

The increasingly urban status of the Cattle Egret Bubulcus ibis in ...

African Journals Online (AJOL)

There are even books on urban bird-watching (e.g. Milne 2006, which includes .... By 2014, the total numbers of Cattle Egret nests found in Kampala had reached just ... It is possible therefore that sharing nesting trees confers some benefit.

Cattle Egret Bubulcus ibis interactions with large mammals in the ...

African Journals Online (AJOL)

While Cattle Egrets Bubulcus ibis are globally widespread, their ecology is not fully understood. Surveys of the species were undertaken in November 2012, and April 2013, in Lake Manyara National Park, Manyara Ranch, and outside the two protected areas. We investigated the effects of host identity, habitat type and host ...

Chlamydia species in free-living Cattle Egret (Bubulcus ibis and Hoopoe (Upupa epops in Egypt

Directory of Open Access Journals (Sweden)

Jakeen K. El-Jakee

2014-06-01

Full Text Available Little information is available on the presence of chlamydia infection in wildlife. This study was conducted to assess the occurrence of chlamydiae in asymptomatic birds from two species of wild birds (Cattle Egret and Hoopoe in Egypt. In the present study Chlamydiaceae was analyzed using Giemsa stain, Giménez stain, fluorescent antibody test (FAT and PCR. The results of these techniques were compared with CFT for detecting Chlamydia psittaci antibodies among the examined birds. The results reveal that 96.4%, 81.8%, 89.1%, 80.0% and 58.2% of the examined samples were positive for chlamydiosis using PCR, Giemsa stain, Giménez stain, FA, and CFT respectively among Hoopoe. The percentages were 90.6%, 77.4%, 83.0%, 75.5% and 66.0% respectively for the previous tests among Cattle Egret birds. The results suggest that Cattle Egret and Hoopoe may be reservoir of Chlamydiaceae species and thus shed the organisms in their excreta. The shedding of chlamydiae by free living birds in Egypt may expose humans that come in contact with these birds to zoonotic risks.

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

EGRET observations of diffuse gamma-ray emission in taurus and perseus

International Nuclear Information System (INIS)

Digel, Seth W.; Grenier, Isabelle A.

2001-01-01

We present an analysis of the interstellar gamma-ray emission observed toward the extensive molecular cloud complexes in Taurus and Perseus by the Energetic Gamma-Ray Experiment Telescope (EGRET). The region's large size (more than 300 square degrees) and location below the plane in the anticenter are advantageous for straightforward interpretation of the interstellar emission. The complex of clouds in Taurus has a distance of ∼140 pc and is near the center of the Gould Belt. The complex in Perseus, adjacent to Taurus on the sky, is near the rim of the Belt at a distance of ∼300 pc. The findings for the cosmic-ray density and the molecular mass-calibrating ratio N(H 2 )/W CO in Taurus and Perseus are compared with results for other nearby cloud complexes resolved by EGRET. The local clouds that now have been studied in gamma rays can be used to trace the distribution of high-energy cosmic rays within 1 kpc of the sun

The foraging behaviour of herons and egrets on the Magela Creek flood plain, Northern Territory

International Nuclear Information System (INIS)

Recher, H.F.; Holmes, R.T.

1982-03-01

Five species of diurnal herons are common on the Magela Creek flood plain and forage along the edges of natural and artifical waterbodies both inside and outside the Ranger Uranium Project Area. The species of heron differ in the kinds and sizes of prey they take, their foraging location, degree of sociality and foraging behaviour. Because it takes relatively large fish, the Great Egret, E. alba, is most likely to be affected by any contamination of the aquatic environment by heavy metals or radionuclides. The Nankeen Night Heron, Nycticorax caledonicus is also abundant on the flood plain and probably feeds on large fish and frogs. The other herons take smaller or immature prey or hunt mostly in terrestrial habitats and are therefore less likely to be affected by contamination of the aquatic environment

On the LHC observation of gluinos from the Egret-preferred region

International Nuclear Information System (INIS)

Bednyakov, V. A.; Budagov, Ju. A.; Gladyshev, A. V.; Kazakov, D. I.; Khramov, E. V.; Khubua, D. I.

2009-01-01

Prospects for observation of a SUSY-like signal from two gluinos g-bar g-bar are investigated within a certain region of the mSUGRA parameter space, where the cross section of the two-gluino production in pp-collisions at the LHC (√s = 14 TeV) is estimated at a rather high level of 17.3 pb. In this so-called EGRET-preferred region, the lightest stable neutralinos χ 1 0 can serve as cold-dark-matter particles and can naturally explain the excess of diffuse Galactic gamma rays observed by the EGRET space apparatus. The g-bar g-bar-event selection relies on a clear signature when decay products of each gluino contain one bb-bar pair, one or two ll-bar pair(s) or one or two light qq-bar pair(s), and a neutralino. Rather high transverse missing energy carried away by the two neutralinos is the essential signature of the events using of which allows the relevant Standard Model background to be reduced significantly. Furthermore, distributions of the reconstructed invariant masses of two opposite-charged-lepton or light-jet pairs produced by the χ 2 0 → χ 1 0 l + l - and χ 2 0 → χ 1 0 qq-bar three-body decays have kinematic end points which measure the difference between masses of χ 2 0 and χ 1 0 . In particular, it was found that these signatures of selected processes demonstrate good prospects for discovery of gluinos at the LHC. These signatures allow one to distinguish different mSUGRA parameters m 1/2 within the EGRET-preferred region (at a higher than 6σ confidence level with 300 fb -1 data).

Mercury and drought along the lower Carson River, Nevada: II. Snowy egret and black-crowned night-heron reproduction on Lahontan Reservoir, 1997-2006

Science.gov (United States)

Hill, Elwood F.; Henry, Charles J.; Grove, Robert A.

2008-01-01

Mercury concentrations in the floodplain of the Carson River Basin in northwestern Nevada are some of the highest ever reported in a natural system. Thus, a portion of the basin including Lahontan Reservoir was placed on the U.S. Environmental Protection Agency’s Natural Priorities List for research and cleanup. Preliminary studies indicated that reproduction in piscivorous birds may be at risk. Therefore, a 10-year study (1997–2006) was conducted to evaluate reproduction of snowy egrets (Egretta thula) and black-crowned night-herons (Nycticorax nycticorax) nesting on Gull Island in Lahontan Reservoir. Special attention was given to the annual flow of the Carson River, the resultant fluctuation of this irrigation reservoir, and the annual exposure of snowy egrets and night-herons to methylmercury (MeHg). The dynamic character of the river due to flooding and drought (drought effect) influenced snowy egret and night-heron reproduction more so than did MeHg contamination of eggs. During an extended drought (2000–2004) in the middle of the study, snowy egret nests containing eggs with concentrations of MeHg (measured as total mercury [THg] ∼ 100% MeHg) ≥0.80 μg THg/g, ww, all failed, but in 1997 and 2006 (wet years with general flooding), substantial numbers of young were produced (but fewer than at nests where eggs contained reproductive threshold of tolerance to MeHg may be associated with habitat quality (food type and abundance). Clearly, drought was the most important factor affecting snowy egret annual productivity. In contrast to snowy egrets, night-herons generally had fewer nests meeting the 0.80 μg THg/g criterion, and those above the criterion were less sensitive to mercury than were snowy egrets. Furthermore, night-herons appeared more tolerant of drought conditions than snowy egrets because they nested earlier, selected more protected nesting sites, and had a more generalist diet that provided additional food options including terrestrial

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....

The heron that laid the golden egg: metals and metalloids in ibis, darter, cormorant, heron, and egret eggs from the Vaal River catchment, South Africa.

Science.gov (United States)

van der Schyff, V; Pieters, R; Bouwman, H

2016-06-01

Metal pollution issues are afforded the highest priority in developing countries. Only one previous study has addressed metals in African bird eggs. We determined the concentration of metals and metalloids in bird eggs from four sites in the Vaal River catchment (VRC) of South Africa to provide data on the current situation. We analysed 16 pools of 77 heron, ibis, darter, egret, and cormorant eggs for 18 metals and metalloids using ICP-MS. We found high concentrations of gold (Au), uranium (U), thallium (Tl), and platinum (Pt) in Grey Heron eggs from Baberspan. Great white egrets from Bloemhof Dam had high concentrations of mercury (Hg). Multivariate analyses revealed strong associations between Au and U, and between palladium (Pd) and Pt. The toxic reference value (TRV) for Hg was exceeded in seven pools. Selenium exceeded its TRV in one pool; in the same pool, copper (Cu) reached its TRV. Compared with other studies, VRC bird eggs had high concentrations of contaminants. Based on these high concentrations, human health might be at risk as Grey Herons and humans share similar food and are therefore exposed to the same contaminants.

Egret-Hibernia(!), a significant petroleum system, northern Grand Banks area, offshore eastern Canada

Science.gov (United States)

Magoon, L.B.; Hudson, T.L.; Peters, K.E.

2005-01-01

Egret-Hibernia(!) is a well-explored petroleum system (3.25 billion barrels oil equivalent [BOE]) located in the Jeanne d'Arc Basin on the Labrador - Newfoundland shelf. Rifting and sediment fill began in the Late Triassic. Egret source rock was deposited in the Late Jurassic at about 153 Ma. After this time, alternating reservoir rock and seal rock were deposited with some syndepositional faulting. By the end of the Early Cretaceous, faults and folds had formed numerous structural traps. For the next 100 m.y., overburden rock thermally matured the source rock when it reached almost 4 km (2.5 mi) burial depth. For 2 km (1.25 mi) below this depth, oil and gas were expelled, until the source was depleted. The expelled petroleum migrated updip to nearby faulted, anticlinal traps, where much of it migrated across faults and upsection to the Hibernia Formation (44% recoverable oil) and Avalon Formation (28%). Accumulation size decreased, and gas content increased from west to east, independent of trap size. These changes correspond to a decrease in source rock richness and quality from west to east. Almost all (96%) of the discovered petroleum resides in the Lower Cretaceous or older reservoir rock units. All accumulations found to date are normally pressured in structural traps. Fifty-two exploration wells found eighteen discoveries. Their size ranges from 1.2 to 0.01 billion BOE. Most discoveries were made between 1979 and 1991. The discovery cycle began with larger accumulations and progressed to smaller accumulations. The estimated sizes of the larger accumulations have grown since 1990. Estimated mean value for undiscovered hydrocarbons is 3.8 billion BOE, thereby raising the ultimate size of Egret-Hibernia(!) to 6.19 billion BOE. Copyright ?? 2005. The American Association of Petroleum Geologists. All rights reserved.

Gamma-Ray Pulsars: Beaming Evolution, Stats and Unident. EGRET Sources

OpenAIRE

Yadigaroglu, I. -A.; Romani, Roger W.

1994-01-01

We compute the variation of the beaming fraction with the efficiency of high energy gamma-ray production in the outer gap pulsar model of Romani and Yadigaroglu. This allows us to correct the fluxes observed for pulsars in the EGRET band and to derive a simple estimate of the variation of efficiency with age. Integration of this model over the population of young neutron stars gives the expected number of gamma-ray pulsars along with their distributions in age and distance. This model also sh...

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.

Photodegradation of wood and depth profile analysis

International Nuclear Information System (INIS)

Kataoka, Y.

2008-01-01

Photochemical degradation is a key process of the weathering that occurs when wood is exposed outdoors. It is also a major cause of the discoloration of wood in indoor applications. The effects of sunlight on the chemical composition of wood are superficial in nature, but estimates of the depth at which photodegradation occurs in wood vary greatly from 80 microm to as much as 2540 mic rom. Better understanding of the photodegradation of wood through depth profile analysis is desirable because it would allow the development of more effective photo-protective treatments that target the surface layers of wood most susceptible to photodegradation. This paper briefly describes fundamental aspects of photodegradation of wood and reviews progress made in the field of depth profile study on the photodegradation of wood. (author)

Utilisation of Estonian energy wood resources

Energy Technology Data Exchange (ETDEWEB)

Muiste, P.; Tullus, H.; Uri, V. [Estonian Agricultural University, Tartu (Estonia)

1996-12-31

In the end of the Soviet period in the 1980s, a long-term energy programme for Estonia was worked out. The energy system was planned to be based on nuclear power and the share of domestic alternative sources of energy was low. The situation has greatly changed after the re-establishment of the Estonian independence, and now wood and peat fuels play an important role in the energy system. Energy consumption in Estonia decreased during the period 1970-1993, but this process has less influenced the consumption of domestic renewable fuels - peat and wood. It means that the share of these fuels has grown. The investment on substitution of imported fossil fuels and on conversion of boiler plants from fossil fuels to domestic fuels has reached the level of USD 100 million. The perspectives of the wood energy depend mainly on two factors; the resources and the price of wood energy compared with other fuels. The situation in wood market influences both the possible quantities and the price. It is typical that the quickly growing cost of labour power in Estonia is greatly affecting the price of energy wood. Though the price level of fuel peat and wood chips is lower than the world market price today, the conditions for using biofuels could be more favourable, if higher environmental fees were introduced. In conjunction with increasing utilisation of biofuels it is important to evaluate possible emissions or removal of greenhouse gases from Estonian forests 3 refs.

Utilisation of Estonian energy wood resources

Energy Technology Data Exchange (ETDEWEB)

Muiste, P; Tullus, H; Uri, V [Estonian Agricultural University, Tartu (Estonia)

1997-12-31

In the end of the Soviet period in the 1980s, a long-term energy programme for Estonia was worked out. The energy system was planned to be based on nuclear power and the share of domestic alternative sources of energy was low. The situation has greatly changed after the re-establishment of the Estonian independence, and now wood and peat fuels play an important role in the energy system. Energy consumption in Estonia decreased during the period 1970-1993, but this process has less influenced the consumption of domestic renewable fuels - peat and wood. It means that the share of these fuels has grown. The investment on substitution of imported fossil fuels and on conversion of boiler plants from fossil fuels to domestic fuels has reached the level of USD 100 million. The perspectives of the wood energy depend mainly on two factors; the resources and the price of wood energy compared with other fuels. The situation in wood market influences both the possible quantities and the price. It is typical that the quickly growing cost of labour power in Estonia is greatly affecting the price of energy wood. Though the price level of fuel peat and wood chips is lower than the world market price today, the conditions for using biofuels could be more favourable, if higher environmental fees were introduced. In conjunction with increasing utilisation of biofuels it is important to evaluate possible emissions or removal of greenhouse gases from Estonian forests 3 refs.

A novel avian-like hepatitis E virus in wild aquatic bird, little egret (Egretta garzetta), in Hungary.

Science.gov (United States)

Reuter, Gábor; Boros, Ákos; Mátics, Róbert; Kapusinszky, Beatrix; Delwart, Eric; Pankovics, Péter

2016-12-01

Hepatitis E virus (HEV), family Hepeviridae, has public health concerns because of its zoonotic potential; however, the host species spectrum, animal to animal transmissions, the natural chain of hepevirus infections and the genetic diversity of HEV in wildlife especially in birds are less known. Using random amplification and next generation sequencing technology a genetically divergent avian HEV was serendipitously identified in wild bird in Hungary. HEV RNA was detected with high faecal viral load (1.33×10 8 genomiccopies/ml) measured by real-time PCR in faecal sample from a little egret (Egretta garzetta). The complete genome of HEV strain little egret/kocsag02/2014/HUN (KX589065) is 6660-nt long including a 18-nt 5' end and a 103-nt 3' end (excluding the poly(A)-tail). Sequence analyses indicated that the ORF1 (4554nt/1517aa), ORF2 (1728nt/593aa) and ORF3 (339nt/112aa) encoded proteins of little egret/kocsag02/2014/HUN shared the highest identity (62.8%, 71% and 61.5%) to the corresponding proteins of genotype 1 avian (chicken) HEV in species Orthohepevirus B, respectively. This study reports the identification and complete genome characterization of a novel orthohepevirus distantly related to avian (chicken) HEVs at the first time in wild bird. It is important to recognize all potential hosts, reservoirs and spreaders in nature and to reconstruct the phylogenetic history of hepeviruses. Birds could be an important reservoir of HEV generally and could be infected with genetically highly divergent strains of HEV. Copyright © 2016 Elsevier B.V. All rights reserved.

EGRET upper limits to the high-energy gamma-ray emission from the millisecond pulsars in nearby globular clusters

Science.gov (United States)

Michelson, P. F.; Bertsch, D. L.; Brazier, K.; Chiang, J.; Dingus, B. L.; Fichtel, C. E.; Fierro, J.; Hartman, R. C.; Hunter, S. D.; Kanbach, G.

1994-01-01

We report upper limits to the high-energy gamma-ray emission from the millisecond pulsars (MSPs) in a number of globular clusters. The observations were done as part of an all-sky survey by the energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory (CGRO) during Phase I of the CGRO mission (1991 June to 1992 November). Several theoretical models suggest that MSPs may be sources of high-energy gamma radiation emitted either as primary radiation from the pulsar magnetosphere or as secondary radiation generated by conversion into photons of a substantial part of the relativistic e(+/-) pair wind expected to flow from the pulsar. To date, no high-energy emission has been detected from an individual MSP. However, a large number of MSPs are expected in globular cluster cores where the formation rate of accreting binary systems is high. Model predictions of the total number of pulsars range in the hundreds for some clusters. These expectations have been reinforced by recent discoveries of a substantial number of radio MSPs in several clusters; for example, 11 have been found in 47 Tucanae (Manchester et al.). The EGRET observations have been used to obtain upper limits for the efficiency eta of conversion of MSP spin-down power into hard gamma rays. The upper limits are also compared with the gamma-ray fluxes predicted from theoretical models of pulsar wind emission (Tavani). The EGRET limits put significant constraints on either the emission models or the number of pulsars in the globular clusters.

A male hooded merganser swims in the waters of KSC

Science.gov (United States)

1999-01-01

The distinctive fan-shaped, black-bordered crest and striped breast identify this hooded merganser, swimming in the waters of the Merritt Island National Wildlife Refuge at Kennedy Space Center. Usually found from Alaska and Canada south to Nebraska, Oregon and Tennessee, hooded mergansers winter south to Mexico and the Gulf Coast, including KSC. The open water of the refuge provides wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds. The 92,000-acre refuge is also habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles.

A merganser swims in the waters of KSC

Science.gov (United States)

1999-01-01

A young female red-breasted merganser swims in the quicksilver water of the Merritt Island National Wildlife Refuge, which shares a boundary with Kennedy Space Center. Usually found from Alaska and Canada south to Nebraska, Oregon and Tennessee, hooded mergansers winter south to Mexico and the Gulf Coast, including KSC. The open water of the refuge provides wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds. The 92,000- acre refuge is also habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles.

Organochlorine contaminants in cormorant, darter, egret, and ibis eggs from South Africa.

Science.gov (United States)

Bouwman, Henk; Polder, Anuschka; Venter, Belinda; Skaare, Janneche U

2008-03-01

During the last 15 years, no research has been published on the levels of pesticides in bird eggs from South Africa, despite the high levels found previously. We analysed eggs from African darter, cattle egret, reed cormorant, African sacred ibis, as well as single eggs from some other species, and found HCB, DDTs, HCHs, chlordanes and PCBs at detectable levels. The presence of mirex in all species was unexpected, since this compound was never registered in South Africa. It also seemed as if terrestrial feeding birds had higher DDE:PCB ratios when compared with aquatic feeding birds. Except for chlordane, the African darter eggs had the highest levels of all other compounds (mean 370 and 300 ng g(-1) ww Sigma pesticides and Sigma PCBs, respectively). Multivariate analysis clearly distinguished the aquatic and terrestrially feeding birds on pollution profile. The African darter (aquatic feeding) and the cattle egret (terrestrial feeding) would be good indicator candidates. Eggshell thinning was detected in the African darter, and was associated with most of the compounds, including DDE and PCBs. We raise a concern that generally longer living birds in warmer climates, laying fewer eggs per clutch, might be at increased risk when compared with trophically similar birds exposed to equivalent levels of pollution in colder climates. Given the scarcity of water and the high biodiversity in Southern Africa, climate change will exert strong pressure, and any additional anthropogenic contamination at levels that can cause subtle behavioural, developmental and reproductive changes, can have serious effects.

Wood anatomy of the Euphorbiaceae, in particular of the subfamily Phyllanthoideae

NARCIS (Netherlands)

Mennega, Alberta M.W.

1985-01-01

The great variety in wood structure of the large family Euphorbiaceae makes it impossible to describe briefly a general wood pattern. Nevertheless, a more or less clear division into four anatomical groups can be made. A short overview is given of the wood structure of the uni-ovulate subfamilies

Study of the spectral characteristics of unidentified galactic EGRET sources. Are they pulsar-like?

Science.gov (United States)

Merck, M.; Bertsch, D. L.; Dingus, B. L.; Esposito, J. A.; Fichtel, C. E.; Fierro, J. M.; Hartman, R. C.; Hunter, S. D.; Kanbach, G.; Kniffen, D. A.; Lin, Y. C.; Mayer-Hasselwander, H. A.; Michelson, P. F.; von Montigny, C.; Muecke, A.; Mukherjee, R.; Nolan, P. L.; Pohl, M.; Schneid, E.; Sreekumar, P.; Thompson, D. J.; Willis, T. D.

1996-12-01

A spectral study of unidentified galactic EGRET sources was performed. The derived spectra are compared to the spectra of pulsars to test the hypothesis, that a significant fraction of these sources are Geminga like radio-quiet pulsars (Yadigaroglu & Romani 1995ApJ...449..211Y). Most of the sources show significantly different spectra than expected under this hypothesis. Of those with spectra consistent with typical pulsar spectra, four are positionally consistent with young spin-powered radio pulsars leaving only very few Geminga type candidates in the sample.

KSC-04PD-0045

Science.gov (United States)

2004-01-01

KENNEDY SPACE CENTER, FLA. -- Three male and one female hooded mergansers swim in the quicksilver water of the Merritt Island National Wildlife Refuge, which shares a boundary with Kennedy Space Center. Usually found from Alaska and Canada south to Nebraska, Oregon and Tennessee, hooded mergansers winter south to Mexico and the Gulf Coast, including KSC. The open water of the refuge provides wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds. The 92,000-acre refuge is also habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles.

Hooded mergansers swim in the waters of KSC

Science.gov (United States)

1999-01-01

A male and two female hooded mergansers swim in the waters of the Merritt Island National Wildlife Refuge at Kennedy Space Center. The male displays its distinctive fan-shaped, black-bordered crest. Usually found from Alaska and Canada south to Nebraska, Oregon and Tennessee, hooded mergansers winter south to Mexico and the Gulf Coast, including KSC. The open water of the refuge provides wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds. The 92,000-acre refuge is also habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles.

A female hooded merganser swims in the waters of KSC

Science.gov (United States)

1999-01-01

A female hooded merganser swims solo in the waters of the Merritt Island National Wildlife Refuge at Kennedy Space Center. The male is distinguished by a fan-shaped, black-bordered crest and striped breast. Usually found from Alaska and Canada south to Nebraska, Oregon and Tennessee, hooded mergansers winter south to Mexico and the Gulf Coast, including KSC. The open water of the refuge provides wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds. The 92,000-acre refuge is also habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles.

Integrated production of wood fuel and pulp wood from young stands; Integroitujen tuotantomenetelmien vertailu

Energy Technology Data Exchange (ETDEWEB)

Korpilahti, A [Metsaeteho Oy, Helsinki (Finland)

1997-12-01

The aim of the study was to clarify the competitiveness of different harvesting chains and processing methods of first thinning wood. Great expectations have been laid on integrated production of wood fuel and pulp wood. Results produced in other bioenergy projects were taken into account, and in this project some field experiments on mechanised felling-bunching and compressing of the load of tree sections during forwarding were carried out. The new processing methods, the MASSAHAKE-method and chain-flail delimbing combined with small-scale drum debarking, still are under development giving a rather unstable data for comparisons. Both in pine and birch dominant stands modern multiple tree logging gave the most favourable results when ranking on the bases of the price of pulp chips. Integrated methods were not very far and they have more potential than methods based on harvesting delimbed short wood. When compared on the bases of the production cost of pulp, integrated methods were in general the most favourable because they give good subsidies on the form of bioenergy. (orig.)

Studies of non-contact methods for roughness measurements on wood surfaces

International Nuclear Information System (INIS)

Lundberg, I.A.S.; Porankiewicz, B.

1995-01-01

The quality of wood surfaces after different kinds of machining processes is a property of great importance for the wood processing industries. Present work is a study, whose objective was to evaluate different non-contact methods, for measurement of the quality of the wood surfaces by correlating them with stylus tracing. A number of Scots Pine samples were prepared by different kinds of wood machining processing. Surface roughness measurements were performed, utilizing two optical noncontact methods. The results indicate that the laser scan method can measure surface roughness on sawn wood with a sufficient degree of accuracy. (author) [de

Considerations on wood energy in a systemic approach

International Nuclear Information System (INIS)

Patino D, Juan F; Quintero, Ricardo S

2008-01-01

The energy obtained from woody biomass or also called wood energy, takes each time more importance as another of the alternatives to the current energy and environmental crisis associated to the excessive use of fossil fuels. Nevertheless, there still exist a series of prejudices, information gaps and disagreements about wood energy that deserves an adequate treatment and disclosure as it is intended in this paper. For this aim, it's necessary to consider wood energy under a systemic view that means, accounting for each component as an interdependent part that managed all together results in the so called wood energy systems. They integrate aspects as the production, logging and transportation of biomass? Conversion to useful forms of energy and utilization in specific applications. Due to the great diversity of factors and agents involved, is necessary to carry out an adequate process of this type of energy systems planning, using for this purpose tools as the Geographical Information Systems (GIS), which can help to obtain the design of optimized systems, that reach their greater potential bringing with them great energy and socio environmental benefits. There are still few experiences in wood energy systems, and especially in Colombia where there is a lack of pilot projects where the convenience of its implementation could be demonstrated offering guidelines for its planning, operation and maintenance. Due to the large opportunities that wood energy presents and its scarce development, it is enormously justified to develop in an ordered and planned way this forgotten sector under a systemic treatment as the one that is considered here.

KSC-04PD-0894

Science.gov (United States)

2004-01-01

KENNEDY SPACE CENTER, FLA. White pelicans swim in a lake north of Kennedy Space Center. In the distance, at right, is a great blue heron. White pelicans winter from Florida and southern California south to Panama. Great blue herons range across the breadth of the United States, as well as north to Alaska and Canada and south to Mexico and the West Indies. The Center shares a boundary north, south and west with the 92,000-acre Merritt Island National Wildlife Refuge, which is a habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles. The marshes and open water of the refuge also provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds.

Carcinogenic risk of chromium, copper and arsenic in CCA-treated wood

International Nuclear Information System (INIS)

Ohgami, Nobutaka; Yamanoshita, Osamu; Thang, Nguyen Dinh; Yajima, Ichiro; Nakano, Chihiro; Wenting, Wu; Ohnuma, Shoko

2015-01-01

We showed that 2.1% of 233 pieces of lumber debris after the Great East Japan Earthquake was chromated copper arsenate (CCA)-treated wood. Since hexavalent chromium (Cr), copper (Cu) and pentavalent arsenic (As) in the debris may be diffused in the air via incineration, we exposed human lung normal (BEAS-2B) and carcinoma (A549) cells to Cr, Cu and As at the molar ratio in a representative CCA-treated wood. Co-exposure to 0.10 μM Cr and 0.06 μM As, which solely had no effect on colony formation, synergistically promoted colony formation in BEAS-2B cells, but not A549 cells, with activation of the PI3K/AKT pathway. Sole exposure and co-exposure to Cu showed limited effects. Since previous reports showed Cr and As concentrations to which human lungs might be exposed, our results suggest the importance to avoid diffusion of Cr and As in the air via incineration of debris including CCA-treated wood after the disaster. - Highlights: • CCA-treated wood was found in debris after the Great East Japan Earthquake in 2011. • Carcinogenic risk of CCA-treated woods was evaluated with human lung cell lines. • Co-exposure to Cr and As synergistically promoted colony formation. • Co-exposure to Cr and As synergistically activated the PI3/AKT pathway. • Effects of sole exposure and co-exposure to Cu on colony formation were limited. - Co-exposure to Cr and As, but not Cu, in CCA-treated wood debris from the Great East Japan Earthquake showed carcinogenicity in vitro.

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.

UV-LED Curing Efficiency of Wood Coatings

OpenAIRE

Véronic Landry; Pierre Blanchet; Gabrielle Boivin; Jean-François Bouffard; Mirela Vlad

2015-01-01

Ultraviolet light emitting diodes (UV-LEDs) have attracted great interest in recent years. They can be used to polymerize coatings, such as those used for prefinished wood flooring. In this project, two lamps were compared for their suitability to be used on a wood flooring finishing line: a UV-microwave and a UV-LED lamp. Low heat emission was found for the UV-LED lamp compared to the UV-microwave one. This study also reveals that the 4 W/cm2 UV-LED lamp used is not powerf...

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.

Western Canadian wood residue production and consumption trends

International Nuclear Information System (INIS)

McCloy, B.

2006-01-01

This presentation considered various trends in western Canadian wood residue production and consumption. Potential markets for wood residue products were also discussed. Trends were reviewed by province for the years 2000-2004. British Columbia (BC) is currently the largest producer of residue in the country, and also retains the largest surpluses of bark, sawdust and shavings. Wood residues in BC are used in pulp and plywood mill production, as well as in the creation of particleboard and MDF. Surplus mill wood residue production in the province has greatly increased due to the Mountain Pine Beetle (MPB) infestation, which has in turn spurred expansion of the BC interior sawmill industry. The infestation has also resulted in a glut of pulp chips. Current wood residue products in Alberta are mostly used in pulp mill combined heat and power (CHP) systems, as well as for wood pellet production and the creation of particleboard and MDF. It was noted that surplus residues are rapidly declining in the province. Saskatchewan's wood residue storage piles are estimated to contain 2,900,000 BDt, while Manitoba surpluses are relatively minor. It was suggested that high natural gas prices have increased the payback on wood energy systems to approximately 2 years. The value of wood residue is now greater than $100/BDt as a substitute for natural gas once the wood energy system has been fully depreciated. Sawmills may now wish to consider equipping themselves to sell wood residue products, as most sawmills only require 20 per cent of their residues for heating purposes. It was concluded that markets for hog fuel wood pellets should be developed in Canada and internationally. Future markets may also develop if natural gas currently used in pulp mill power boilers and lime kilns is replaced with wood residue energy systems. refs., tabs., figs

WOOD PROPERTIES AND EFFECT OF WOOD PROPERTIES ON THE WOOD FINISHING

Directory of Open Access Journals (Sweden)

Abdulkadir Malkoçoğlu

2006-04-01

Full Text Available Wood is basic raw material for furniture and joinery industries with wood structures. Wood is a biological material that has widely different properties depending on species, geographic area where the tree grew, the growth condition, size of the tree at harvest, sawing, and other manufacturing processes. Wood properties have been characterized within two groups as natural and manufacturing factors that effects finishing performance. Grow rate, density, knots, moisture content, extractives and juvenile wood are natural characteristics. Grain orientation, texture, drying and performance expectations are manufacturing characteristics. In this review, the effects of natural and manufacturing characteristics are discussed on the surface finishing performance of wood.

Morphological, Histological and Histochemical Study of the Lingual Salivary Glands of the Little Egret, Egretta garzetta

International Nuclear Information System (INIS)

Almansour, Mansour I.; Jarrar, Bashir M.

2007-01-01

The present study aimed to study the morphological, histological and histochemical characterizations of the lingual salivary glands of the little egret, Egretta garzetta. The glands are composed of two posterior entities at the base of the tongue and one anterior entity on the dorsal surface of the free lingual part. These glands are made of mucoserous cells that elaborate sialomucins, sulfomucins and proteins, but they are devoid of glycogen and neutral mucosubstances. The findings of the present study were compared with those reported for other birds in correlation with their phylogeny and feeding habits. (author)

In want of measurements of air pollution from wood smoke

DEFF Research Database (Denmark)

Czeskleba-Dupont, Rolf; Czeskleba-Dupont, Solveig

2007-01-01

, handy measuring instruments at their disposal, so that the inconvenience from smoke could be analytically documented. The contribution details arguments on serious wood smoke pollution, health problems and  regulations  needed.  Local measurements should be promoted  regarding air pollution from...... of ventilation and fine cracks in the outer walls. In the night people can not air the bedrooms without getting the rooms filled with wood smoke. Until now the regulations of wood smoke have been ineffective. - It would be a great step forward, if local authorities and smoke affected people could have effective...

Important Non-Wood Forest Products in Turkey: An Econometric Analysis

Directory of Open Access Journals (Sweden)

R. Kurt

2016-12-01

Full Text Available Wood resources obtained from forest and non-wood forest products (NWFP have gained great importance recently as their economic values keeps increasing by the day. In this study, forecasting of Turkish Non-Wood Forest Products such as thyme, bay leaves, salvia and pine nut export amounts was carried out using a linear regression analysis method for the next fifteen years based on the data for the years between 1990 and 2009. Moreover, estimated import values and actual import values from the last years were compered and analyzed. Finally, predictions on future trends were made.

Wood : adhesives

Science.gov (United States)

A.H. Conner

2001-01-01

This chapter on wood adhesives includes: 1) Classification of wood adhesives 2) Thermosetting wood adhesives 3) Thermoplastic adhesives, 4) Wood adhesives based on natural sources 5) Nonconventional bonding of wood 6) Wood bonding.

Aspects of the breeding biology of the Cattle Egret (Bubulcus ibis) in Montserrat, West Indies, and its impact on nest vegetation

Science.gov (United States)

W.J. Arendt; A.I. Arendt

1988-01-01

Aspects of the Cattle Egret's reproductive ecology and habitat use in an insular environment were studied on Montserrat, West Indies. Average size of 290 nests (17.9 cm) was smaller than sizes reported in the literature and was attributed to a paucity of available nesting materials. We measured 330 eggs to determine: egg volume (24,117.04 mm3), fresh egg weight (...

Comparative study of Danish prefab houses made of wood

DEFF Research Database (Denmark)

Wraber, Ida Kristina

2011-01-01

The use of wood in Danish prefab building projects is increasing, but there is not a strong architectural tradition in Denmark for constructing timber housing. This paper therefore contains a comparative study of various manners of incorporating architectural features in prefab houses made of wood....... In the study four Danish prefab housing concepts based on wood con¬struc¬tion is compared and discussed, in order to investigate and exemplify how it is possible to work with architectural quality in prefab timber housing and maximise the use of the material, the prefab production and the architectural values....... It was concluded that especially two aspects are of great importance for the concrete handling of the architectural quality of prefab houses made of wood; 1) flexibility in relation to user and site, and 2) the interaction between form, logics and material. It is suggested that keeping these two aspects in mind...

Mercury and drought along the Lower Carson River, Nevada: III. effects on blood and organ biochemistry and histopathology of snowy egrets and black-crowned night-herons on Lahontan Reservoir, 2002-2006

Science.gov (United States)

Hoffman, David J.; Henny, Charles J.; Hill, Elwood F.; Grove, Robert A.; Kaiser, James L.; Stebbins, Katherine R.

2009-01-01

A 10-year study (1997-2006) was conducted to evaluate reproduction and health of aquatic birds in the Carson River Basin of northwestern Nevada (on the U.S. Environmental Protection Agency Natural Priorities List) due to high mercury (Hg) concentrations from past mining activities. This part of the study evaluated physiological associations with blood Hg in young snowy egrets (Egretta thula) and black-crowned night-herons (Nycticorax nycticorax), and organ biochemistry and histopathological effects in snowy egrets on Lahontan Reservoir (LR) from the period 2002-2006. LR snowy egret geometric mean total Hg concentrations (μg/g ww) ranged from 1.5 to 4.8 for blood, 2.4 to 3.1 liver, 1.8 to 2.5 kidneys, 1.7 to 2.4 brain, and 20.5 to 36.4 feathers over these years. For night-herons, mean Hg for blood ranged from 1.6 to 7.4. Significant positive correlations were found between total Hg in blood and five plasma enzyme activities of snowy egrets suggesting hepatic stress. Histopathological findings revealed vacuolar changes in hepatocytes in LR snowy egrets as well as correlation of increased liver inflammation with increasing blood and tissue Hg. Hepatic oxidative effects were manifested by decreased hepatic total thiol concentration and glutathione reductase activity and elevated hepatic thiobarbituric acid-reactive substances (TBARS), a measure of lipid peroxidation. However, other hepatic changes indicated compensatory mechanisms in response to oxidative stress, including decreased oxidized glutathione (GSSG) concentration and decreased ratio of GSSG to reduced glutathione. In young black-crowned night-herons, fewer correlations were apparent. In both species, positive correlations between blood total Hg and plasma uric acid and inorganic phosphorus were suggestive of renal stress, which was supported by histopathological findings. Both oxidative effects and adaptive responses to oxidative stress were apparent in kidneys and brain. Vacuolar change and inflammation in

Growth of high-density ZnO nanorods on wood with enhanced photostability, flame retardancy and water repellency

Energy Technology Data Exchange (ETDEWEB)

Kong, Lizhuo; Tu, Kunkun; Guan, Hao [Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091 (China); Wang, Xiaoqing, E-mail: wangxq@caf.ac.cn [Research Institute of Forestry New Technology, Chinese Academy of Forestry, Beijing 100091 (China); Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091 (China)

2017-06-15

Highlights: • ZnO nanorod arrays were deposited on the wood surface via a hydrothermal process. • The assembled ZnO nanorod arrays greatly enhanced the photostability of wood. • The treated wood can sustain direct exposure to flame with only minor smoldering. • The ZnO-coated wood modified with stearic acid showed a superhydrophobic surface. - Abstract: Zinc oxide (ZnO) nanorod arrays were successfully assembled on the wood surface in situ via a two-step process consisting of formation of ZnO seeds and subsequent crystal growth under hydrothermal conditions at a low temperature. The morphology and crystalline structure of the formed ZnO nanorods were studied by field-emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). Highly dense and uniform arrays of ZnO nanorods with well-defined hexagonal facets were generated on the wood surface by tuning the concentration of the ZnO growth solution during the hydrothermal treatment. Accelerated weathering tests indicated that the assembled ZnO nanorod arrays were highly protective against UV radiation and greatly enhanced the photostability of the coated wood. Meanwhile, the ZnO nanorod-coated wood can withstand continuous exposure to flame with only minor smoldering in contrast with the pristine wood catching fire easily and burning rapidly. Moreover, when further modified with low-surface-energy stearic acid, the ZnO nanorod decorated wood surface can be transformed into a superhydrophobic surface, with a water contact angle (CA) of ∼154°. Such ZnO nanorod-modified woods with enhanced photostability, flame retardancy and water repellency offer an interesting alternative to conventional wood preservation strategies, highlighting their potential applications in some novel wood products.

Growth of high-density ZnO nanorods on wood with enhanced photostability, flame retardancy and water repellency

International Nuclear Information System (INIS)

Kong, Lizhuo; Tu, Kunkun; Guan, Hao; Wang, Xiaoqing

2017-01-01

Highlights: • ZnO nanorod arrays were deposited on the wood surface via a hydrothermal process. • The assembled ZnO nanorod arrays greatly enhanced the photostability of wood. • The treated wood can sustain direct exposure to flame with only minor smoldering. • The ZnO-coated wood modified with stearic acid showed a superhydrophobic surface. - Abstract: Zinc oxide (ZnO) nanorod arrays were successfully assembled on the wood surface in situ via a two-step process consisting of formation of ZnO seeds and subsequent crystal growth under hydrothermal conditions at a low temperature. The morphology and crystalline structure of the formed ZnO nanorods were studied by field-emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). Highly dense and uniform arrays of ZnO nanorods with well-defined hexagonal facets were generated on the wood surface by tuning the concentration of the ZnO growth solution during the hydrothermal treatment. Accelerated weathering tests indicated that the assembled ZnO nanorod arrays were highly protective against UV radiation and greatly enhanced the photostability of the coated wood. Meanwhile, the ZnO nanorod-coated wood can withstand continuous exposure to flame with only minor smoldering in contrast with the pristine wood catching fire easily and burning rapidly. Moreover, when further modified with low-surface-energy stearic acid, the ZnO nanorod decorated wood surface can be transformed into a superhydrophobic surface, with a water contact angle (CA) of ∼154°. Such ZnO nanorod-modified woods with enhanced photostability, flame retardancy and water repellency offer an interesting alternative to conventional wood preservation strategies, highlighting their potential applications in some novel wood products.

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.

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

Emission of dioxins from fireplaces and wood-burning stoves

International Nuclear Information System (INIS)

Hansen, K.J.; Vikelsoee, J.; Madsen, H.

1994-01-01

In 1988 the Environmental Report No. 149 was published. The result of this investigation was that exceptionally large quantities of dioxin were emitted from burning of clean wood in fireplaces and wood-burning stoves. The conclusion was, however, that it was a preliminary investigation subject to great uncertainties. So it was recommended to make further investigations. The project was continued in 1990, and the present report is the result of this investigation. The fuels applied were logged and treated as an integral part of the test in order to take precautions against contamination. A new test arrangement with a dilution channel was developed in order to be able to take samples. The dilution channel made it possible to take out representative samples for the entire combustion process. Four wood-burning stoves were chosen for the experiments. Two stoves representing those sold from 1960 till 1990. One new stove approved according to DS 887 and finally a prototype stove. The dioxin analysis method was developed so that it could better handle the presence of tar in the samples taken. Danmarks Miljoe Undersoegelse (DMU) - The Danish Environmental Investigations - carried out a great work of development and documentation in this field. Before the main experiment a validation of the sampling and the analysis method was made. The conclusion was that the sampling and analysis method was satisfactory and that a continuity from Environmental Project no. 149 was ensured. During the execution of the present project a probable explanation of the high dioxin emission has been found which were reported in Environmental Project No. 149. The reason is in all probability contamination from burning of pressure-creosoted wood with burning of clean wood. The present report contains a number of appendices showing results from single experiments, references and a number of references to supplementary reports which were elaborated during the progress of the work. (EG)

New Theoretical Estimates of the Contribution of Unresolved Star-Forming Galaxies to the Extragalactic Gamma-Ray Background (EGB) as Measured by EGRET and the Fermi-LAT

Science.gov (United States)

Venters, Tonia M.

2011-01-01

We present new theoretical estimates of the contribution of unresolved star-forming galaxies to the extragalactic gamma-ray background (EGB) as measured by EGRET and the Fermi-LAT. We employ several methods for determining the star-forming galaxy contribution the the EGB, including a method positing a correlation between the gamma-ray luminosity of a galaxy and its rate of star formation as calculated from the total infrared luminosity, and a method that makes use of a model of the evolution of the galaxy gas mass with cosmic time. We find that depending on the model, unresolved star-forming galaxies could contribute significantly to the EGB as measured by the Fermi-LAT at energies between approx. 300 MeV and approx. few GeV. However, the overall spectrum of unresolved star-forming galaxies can explain neither the EGRET EGB spectrum at energies between 50 and 200 MeV nor the Fermi-LAT EGB spectrum at energies above approx. few GeV.

Sandhill cranes browse for food near VAB

Science.gov (United States)

2000-01-01

A family of sandhill cranes searches for food on the grounds near the Vehicle Assembly Building. The cranes have been a constant sight in the Launch Complex 39 area during the month of May. Sandhill cranes range from Siberia, Alaska and Arctic islands to Michigan, Minnesota and California; from Florida to Texas. They prefer large freshwater marshes, prairie ponds and marshy tundra. KSC shares a boundary with the Merritt Island National Wildlife Refuge, which encompasses 92,000 acres that are a habitat for more than 331 species of birds, 31 mammals, 117 fishes, and 65 amphibians and reptiles. The marshes and open water of the refuge provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds, as well as a variety of insects.

Sandhill cranes hunting food at KSC

Science.gov (United States)

2000-01-01

A pair of Sandhill Cranes searches for food with their still- fluffy fledgling close by. The trio have been seen wandering the grassy areas in the KSC Launch Complex 39 area. Sandhill cranes range from Siberia, Alaska and Arctic islands to Michigan, Minnesota and California; from Florida to Texas. They prefer large freshwater marshes, prairie ponds and marshy tundra. KSC shares a boundary with the Merritt Island National Wildlife Refuge, which encompasses 92,000 acres that are a habitat for more than 331 species of birds, 31 mammals, 117 fishes, and 65 amphibians and reptiles. The marshes and open water of the refuge provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds, as well as a variety of insects.

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...

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...

Organochlorine pesticide, polychlorinated biphenyl, trace element and metal residues in bird eggs from Salton Sea, California, 2004

Science.gov (United States)

Henny, Charles J.; Anderson, T.W.; Crayon, J.J.

2008-01-01

The Salton Sea is a highly eutrophic, hypersaline terminal lake that receives inflows primarily from agricultural drainages in the Imperial and Coachella valleys. Impending reductions in water inflow at Salton Sea may concentrate existing contaminants which have been a concern for many years, and result in higher exposure to birds. Thus, waterbird eggs were collected and analyzed in 2004 and compared with residue concentrations from earlier years; these data provide a base for future comparisons. Eggs from four waterbird species (black-crowned night-heron [Nycticorax nycticorax], great egret [Ardea alba], black-necked stilt [Himantopus mexicanus], and American avocet [Recurvirostra Americana]) were collected. Eggs were analyzed for organochlorine pesticides, polychlorinated biphenyls (PCBs), metals, and trace elements, with current results compared to those reported for eggs collected from the same species and others during 1985a??1993. The two contaminants of primary concern were p,pa??-DDE (DDE) and selenium. DDE concentrations in night-heron and great egret eggs collected from the northwest corner of Salton Sea (Whitewater River delta) decreased 91 and 95%, respectively, by 2004, with a concomitant increase in eggshell thickness for both species. Decreases in bird egg DDE levels paralleled those in tissues of tilapia (Oreochromis mossambicus ?? O. urolepis), an important prey species for herons and egrets. Despite most nests of night-herons and great egrets failing in 2004 due to predation, predicted reproductive effects based on DDE concentrations in eggs were low or negligible for these species. The 2004 DDE findings were in dramatic contrast to those in the past decade, and included an 81% decrease in black-necked stilt eggs, although concentrations were lower historically than those reported in night-herons and egrets. Selenium concentrations in black-necked stilt eggs from the southeast corner of Salton Sea (Davis Road) were similar in 1993 and 2004, with 4

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.

Growth and wood properties of genetically improved loblolly pine: propagation type comparison and genetic parameters

Science.gov (United States)

Finto Antony; Laurence Schimleck; Lewis Jordan; Benjamin Hornsby; Joseph Dahlen; Richard Daniels; Alexander Clark; Luis Apiolaza; Dudley Huber

2013-01-01

The use of clonal varieties in forestry offers great potential to improve growth traits (quantity) and wood properties (quality) of loblolly pine (Pinus taeda L.). Loblolly pine trees established via somatic embryogenesis (clones), full-sib zygotic crosses, and half-sib zygotic open-pollinated families were sampled to identify variation in growth and wood properties...

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...

Wood burning

Energy Technology Data Exchange (ETDEWEB)

Winkelmann, H

1955-01-01

Discussed are the use of wood as a fuel, the technique of wood combustion and the operation of wood-burning stoves for cooking and heating. In addition, there is a section which reviews the use of wood stoves in various countries and lists manufacturers of stoves, central heating furnaces and in some cases sawdust burners.

Effect of Trichoderma-enriched organic charcoal in the integrated wood protection strategy.

Directory of Open Access Journals (Sweden)

Javier Ribera

Full Text Available The gradual elimination of chromium from wood preservative formulations results in higher Cu leaching and increased susceptibility to wood decay fungi. Finding a sustainable strategy in wood protection has become of great interest among researchers. The objective of these in vitro studies was to demonstrate the effect of T-720-enriched organic charcoal (biochar against five wood decay basidiomycetes isolated from strongly damaged poles. For this purpose, the antagonistic potential of Trichoderma harzianum (strain T-720 was confirmed among other four Trichoderma spp. against five brown-rot basidiomycetes in dual culture tests. T-720 was genetically transformed and tagged with the green fluorescent protein (GFP in order to study its antagonistic mechanism against wood decay basidiomycetes. It was also demonstrated that T-720 inhibits the oxalic acid production by basidiomycetes, a well-known mechanism used by brown-rot fungi to detoxify Cu from impregnated wood. Additionally, this study evaluated the effect of biochar, alone or in combination with T-720, on Cu leaching by different preservatives, pH stabilization and prevention of wood decay caused by five basidiomycetes. Addition of biochar resulted in a significant Cu binding released from impregnated wood specimens. T-720-enriched biochar showed a significant reduction of wood decay caused by four basidiomycetes. The addition of T-720-enriched biochar to the soil into which utility poles are placed may improve the efficiency of Cr-free wood preservatives.

VARIATION IN THE FIBRE CHARACTERISTICS OF THE WOOD OF ...

African Journals Online (AJOL)

cani

The study investigated the fibre characteristics and chemical composition of Vitex doniana towards determining its potentials for pulp and paper. Fibre dimensions are of great importance because of the strong correlation between it and the strength properties of wood and paper. Axial and radial examinations of fibre ...

Competitive outcomes between wood-decaying fungi are altered in burnt wood.

Science.gov (United States)

Edman, Mattias; Eriksson, Anna-Maria

2016-06-01

Fire is an important disturbance agent in boreal forests where it creates a wide variety of charred and other types of heat-modified dead wood substrates, yet how these substrates affect fungal community structure and development within wood is poorly understood. We allowed six species of wood-decaying basidiomycetes to compete in pairs in wood-discs that were experimentally burnt before fungal inoculation. The outcomes of interactions in burnt wood differed from those in unburnt control wood for two species:Antrodia sinuosanever lost on burnt wood and won over its competitor in 67% of the trials compared to 40% losses and 20% wins on unburnt wood. In contrast, Ischnoderma benzoinumwon all interactions on unburnt wood compared to 33% on burnt wood. However, the responses differed depending on the identity of the competing species, suggesting an interaction between competitor and substrate type. The observed shift in competitive balance between fungal species probably results from chemical changes in burnt wood, but the underlying mechanism needs further investigation. Nevertheless, the results indicate that forest fires indirectly structure fungal communities by modifying dead wood, and highlight the importance of fire-affected dead wood substrates in boreal forests. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

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

THE JAMES MADISON WOOD QUADRANGLE, STEPHENS COLLEGE, COLUMBIA, MISSOURI.

Science.gov (United States)

MCBRIDE, WILMA

THE JAMES MADISON WOOD QUADRANGLE AT STEPHENS COLLEGE IS A COMPLEX OF BUILDINGS DESIGNED TO MAKE POSSIBLE A FLEXIBLE EDUCATIONAL ENVIRONMENT. A LIBRARY HOUSES A GREAT VARIETY OF AUDIO-VISUAL RESOURCES AND BOOKS. A COMMUNICATION CENTER INCORPORATES TELEVISION AND RADIO FACILITIES, A FILM PRODUCTION STUDIO, AND AUDIO-VISUAL FACILITIES. THE LEARNING…

Quaternized wood as sorbent for hexavalent chromium.

Science.gov (United States)

Low, K S; Lee, C K; Lee, C Y

2001-01-01

The potential of quaternized wood (QW) chips in removing hexavalent chromium from synthetic solution and chrome waste under both batch and continuous-flow conditions was investigated. Sorption was found to be dependent on pH, metal concentration, and temperature. QW chips provide higher sorption capacity and wider pH range compared with untreated wood chips. The equilibrium data could be fitted into the Langmuir isotherm model, and maximum sorption capacities were calculated to be 27.03 and 25.77 mg/g in synthetic chromate solution and chrome waste, respectively. The presence of sulfate in high concentration appeared to suppress the uptake of chromium by QW chips. Column studies showed that bed depth influenced the breakthrough time greatly whereas flow rate of influent had little effect on its sorption on the column.

A Roseate Spoonbill hunts for food in the water.

Science.gov (United States)

1999-01-01

A Roseate Spoonbill sweeps the water for food in the Merritt Island National Wildlife Refuge, which shares a boundary with Kennedy Space Center. The brilliant pink bird is named for its straight bill with the broad spatulate tip. Preferring a habitat of mangroves, it is usually found on the coasts of southern Florida and Texas, occasionally in Louisiana., in the West Indies, Mexico and Central and South America. Spoonbills feed on shrimps and fish in shallow waters, sweeping their bills from side to side and scooping up whatever they encounter. The 92,000- acre refuge is a habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles. The marshes and open water of the refuge also provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds.

Wood Identification of 18th Century Furniture. Interpreting Wood Naming Inventoires

Directory of Open Access Journals (Sweden)

Rocio Astrid BERNAL

2011-09-01

Full Text Available The 18th century Portuguese church furniture represents an extraordinary richness recognised worldwide, which demands safeguarding and valorisation. The identification of the wood of furniture artworks is the most important component for its comprehension and preservation. In this work wood anatomical characters of an 18th century Portuguese decorative furniture set from the Colegiada de São Martinho de Cedofeita, in Porto, were analysed to identify the woods used for manufacturing and to clarify their common names. Furthermore, the objectives were to recognise some of the criteria for choice of wood as well as the source of each wood. The woods identified from 16 fragments belong to Apuleia sp., Acacia sp., Neolamarckia sp. and Castanea sativa. Apuleia sp. and Acacia sp. woods most likely arrived from Brazil, while the Neolamarckia sp. woods likely arrived from India and the C. sativa woods from Portugal. The results are in accordance with the known Portuguese colonial sea routes of the 15th -18th centuries. Interestingly the terms found in the inventories can refer to finishing methods instead to the name of the woods, as for instance “oil wood” can refer to “oiled wood” or “linseed oiled wood”. The species choice may be related to the mechanical properties of the wood as well as the original tree size. Two large planks of Acacia sp. were used for the top of the “Portuguese arcaz”, and Apuleia sp. was found on main structural elements of this set of furniture, suggesting that wood colour was also important. Woods from Neolamarckia sp. and C. sativa, were also identified, being Castanea wood present only in the most recent pieces of the furniture set.

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)

Wood-related occupations, wood dust exposure, and sinonasal cancer.

Science.gov (United States)

Hayes, R B; Gerin, M; Raatgever, J W; de Bruyn, A

1986-10-01

A case-control study was conducted to examine the relations between type of woodworking and the extent of wood dust exposure to the risks for specific histologic types of sinonasal cancer. In cooperation with the major treatment centers in the Netherlands, 116 male patients newly diagnosed between 1978 and 1981 with primary malignancies of epithelial origin of this site were identified for study. Living controls were selected from the municipal registries, and deceased controls were selected from the national death registry. Interviews were completed for 91 (78%) cases and 195 (75%) controls. Job histories were coded by industry and occupation. An index of exposure was developed to classify the extent of occupational exposure to wood dust. When necessary, adjustment was made for age and usual cigarette use. The risk for nasal adenocarcinoma was elevated by industry for the wood and paper industry (odds ratio (OR) = 11.9) and by occupation for those employed in furniture and cabinet making (OR = 139.8), in factory joinery and carpentry work (OR = 16.3), and in association with high-level wood dust exposure (OR = 26.3). Other types of nasal cancer were not found to be associated with wood-related industries or occupations. A moderate excess in risk for squamous cell cancer (OR = 2.5) was associated with low-level wood dust exposure; however, no dose-response relation was evident. The association between wood dust and adenocarcinoma was strongest for those employed in wood dust-related occupations between 1930 and 1941. The risk of adenocarcinoma did not appear to decrease for at least 15 years after termination of exposure to wood dust. No cases of nasal adenocarcinoma were observed in men whose first exposure to wood dust occurred after 1941.

Effect of cement/wood ratios and wood storage conditions on hydration temperature, hydration time, and compressive strength of wood-cement mixtures

Science.gov (United States)

Andy W.C. Lee; Zhongli Hong; Douglas R. Phillips; Chung-Yun Hse

1987-01-01

This study investigated the effect of cement/wood ratios and wood storage conditions on hydration temperature, hydration time, and compressive strength of wood-cement mixtures made from six wood species: southern pine, white oak, southern red oak, yellow-poplar, sweetgum, and hickory. Cement/wood ratios varied from 13/1 to 4/1. Wood storage conditions consisted of air-...

Inventory of contaminants in waste wood; Inventering av foeroreningar i returtrae

Energy Technology Data Exchange (ETDEWEB)

Jermer, Joeran; Ekvall, Annika; Tullin, Claes [Swedish National Testing and Research Inst., Boraas (Sweden)

2001-03-01

Waste wood is increasingly used as fuel in Sweden. It is of Swedish origin as well as imported, mainly from Germany and the Netherlands. The waste wood is contaminated by e.g. paint and wood preservatives and objects of metal, glass, plastics etc. The contaminants may cause technical problems such as deposits and corrosion as well as plugging of air openings. The present study has focussed on potential contaminants in waste wood that could cause problems of technical as well as environmental nature. The major chemical contaminants are surface treatments (paints etc) and wood preservatives. The surface treatments contribute in particular to contaminants of zinc and lead. In some cases zinc has been found to cause severe deposits in the furnaces. Surface treatments also contribute to increased levels of sodium, chlorine, sulphur and nitrogen. Preservative-treated wood is the most important source of increased levels of copper, chromium and arsenic in the waste wood. Waste wood imported from Germany contains less arsenic but the same amount of copper and chromium as Swedish waste wood. The contents of mercury in German waste wood can be expected to be higher than in waste wood of Swedish origin. The fraction consisting of wood-based panels is comparably free from contaminants but as a result of the high contents of adhesives wood-based panels contribute to a higher proportion of nitrogen in waste wood than in forest residues. A great number of non-wood compounds (such as plastics and metals) do also contaminate waste wood. By careful and selective demolition and various sorting procedures most non-wood compounds will be separated from the waste wood. Waste sorting analyses carried out indicate that the waste wood contains approximately 1% non-wood compounds, mainly plastic and metal compounds, glass, dirt, concrete, bricks and gypsum. This may seem to be a small proportion, but if large amounts of waste wood are incinerated the non-wood compounds will inevitably cause

Application of photocuring technique on wood surface and its prospects in Bangladesh

International Nuclear Information System (INIS)

Bhattcacharia, S.K.; Khan, Mubarak A.

2005-01-01

Photocuring technique has unveiled a new horizon in polymer science. Application of photocuring technique on wood surface has enhanced the use of low grade wood. As Bangladesh is an overpopulated country, necessity of good quality wood is increasing day by day. So low grade wood, like Simul or Partex, locally produced particleboard, would come out with great use. As Partex board, produced from Jute sticks and various types of indigenous low grade wood and particle board are abundant in Bangladesh, so photocuring could play a major role to improve the quality of low grade wood and serve the nation. Already, a lot of research works were carried out by the local scientists to improve the wood surface using UV curing method. Different formulations were also developed by the local scientists using various oligomer, monomer and different types of additives. The used oligomers are epoxy, polyester, urethane, etc. and monomers of different functionalities and used additives are acrylic monomer, CaCO 3 , sand, MgSiO 3 , talc, etc. Thin films were prepared on glass plate with different formulations using UV radiation and different characteristics properties (pendulum hardness, abrasion, gloss (60 deg. and 20 deg.), microscratch hardness, weathering effect, adhesion strength, etc.) were studied. Now, a Pilot Plant has already been established with the financial assistance by the government of Bangladesh, worth US$ 3.5 million

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

Dr. Byron McKeeby's contribution to Grant Wood's "American Gothic".

Science.gov (United States)

Christen, Arden G; Christen, Joan A

2004-07-01

Grant Wood (1891-1942) was a major American regionalist artist from Iowa who produced his world famous icon, American Gothic in 1930. Along with Mona Lisa and Whistler's Mother, this work has become one of the most recognized paintings in the world. While it has been greatly admired by most of its viewers, it has been criticized by others. Currently on display at the Art Institute of Chicago, this oil painting portrays a grim faced farmer and his somber daughter who are resolutely standing in front of their rural, Gothic Revival farmhouse. The tall, gaunt farmer, looking straight ahead, firmly holds a pitchfork whose tines point upward, while his daughter, with her eyes averted appears to be showing disapproval. In American art, it is unusual to find the hard, cold realism and honest, direct and earthy qualities that Wood captures in American Gothic. Wood's actual intention was to present the work as a subtle and witty commentary on midwestern, rural life. To achieve his goal, Wood emulated the meticulous style and technique of the 16th century Flemish masters. His sister, Nan Wood Graham (1900-1990), and his 62-year-old dentist, Dr. Byron H. McKeeby (1867-1950), posed for the painting. This article describes how Grant developed this artistic style which is reflected in American Gothic. Additionally, it examines the strained interactions between Grant Wood, the artist, and Dr. Byron McKeeby, the model.

Wood plastic composites based on microfibrillar blends of high density polyethylene/poly(ethylene terephthalate).

Science.gov (United States)

Lei, Yong; Wu, Qinglin

2010-05-01

High-melting-temperature poly(ethylene terephthalate) (PET) was successfully introduced into wood plastic composites through a two-step reactive extrusion technology. Wood flour was added into pre-prepared PET/high density polyethylene (HDPE) microfibrillar blends (MFBs) in the second extrusion at the temperature for processing HDPE. Addition of 25% in situ formed PET microfibers obviously increased the mechanical properties of HDPE, and more significant enhancement by the in situ formed recycled PET microfibers was observed for the recycled HDPE. Adding 2% E-GMA improved the compatibility between matrix and microfibers in MFBs, resulting further enhanced mechanical properties. The subsequent addition of 40% wood flour did not influence the size and morphology of PET microfibers, and improved the comprehensive mechanical properties of MFBs. The wood flour increased the crystallinity level of HDPE in the compatibilized MFB in which PET phase did not crystallize. The storage modulus of MFB was greatly improved by wood flour. Published by Elsevier Ltd.

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).

Analysis of Location Quotient index of poplar wood processing value chain in Iran

OpenAIRE

omid hosseinzadeh; Marzieh Hajjarian; Samira Porbar

2016-01-01

Value added in the poplar wood value chain has great economic effects for poplar farmers and have a fundamental role in sustainable supplying of required cellulosic materials of industries in long-term. The purpose of this study was to analyze the value chain of poplar and use the results to improve it. In order to determine the poplar value chain, Porter's value chain analysis framework was used. The statistical society consists of 76 experts to identify poplar wood value who were active in ...

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

2018-08-01

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.

THE SEARCH FOR BLAZARS AMONG THE UNIDENTIFIED EGRET gamma-RAY SOURCES

Directory of Open Access Journals (Sweden)

Pieter J. Meintjes

2013-12-01

Full Text Available In this paper we report the results of a multi-wavelength follow-up study of selected flat spectrum extragalactic radio-optical counterparts within the error boxes of 13 unidentified EGRET sources. Two of these previously unidentified counterparts have been selected for optical photometric and spectroscopic follow-up studies. Spectroscopic observations made with the 4.1m SOAR telescope at Cerro Pachón, Chile, showed that the spectra of the optical counterparts of 3EG J0821−5814 (PKS J0820−5705 and 3EG J0706−3837 (PMN J0710−3835 correspond to a flat spectrum radio quasar (FSRQ and LINER-Seyfert I galaxy respectively. Optical photometry of these sources, performed with the 1.0m telescope at Sutherland (South-Africa shows noticeable intranight variability for PKS J0820−5705, as well as a 5 sigma variation of the mean brightness in the R-filter over a timescale of three nights. Significant variability has been detected in the B-band for PMN J0710−3835 as well. The gamma-ray spectral indices of all 13 candidates range between 2–3, correlating well with the BL Lacs and FSRQs detected with Fermi-LAT in the first 11 months of operation.

Finishing of wood

Science.gov (United States)

R. Sam Williams

1999-01-01

The primary function of any wood finish (paint, varnish, and stain, for example) is to protect the wood surface, help maintain a certain appearance, and provide a cleanable surface. Although wood can be used both outdoors and indoors without finishing, unfinished wood surfaces exposed to the weather change color, are roughened by photodegradation and surface checking,...

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)

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

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...

Integrated control of wood destroying basidiomycetes combining Cu-based wood preservatives and Trichoderma spp.

Science.gov (United States)

Ribera, Javier; Fink, Siegfried; Bas, Maria Del Carmen; Schwarze, Francis W M R

2017-01-01

The production of new generation of wood preservatives (without addition of a co-biocide) in combination with an exchange of wood poles on identical sites with high fungal inoculum, has resulted in an increase of premature failures of wood utility poles in the last decades. Wood destroying basidiomycetes inhabiting sites where poles have been installed, have developed resistance against wood preservatives. The objective of the in vitro studies was to identify a Trichoderma spp. with a highly antagonistic potential against wood destroying basidiomycetes that is capable of colonizing Cu-rich environments. For this purpose, the activity of five Trichoderma spp. on Cu-rich medium was evaluated according to its growth and sporulation rates. The influence of the selected Trichoderma spp. on wood colonization and degradation by five wood destroying basidiomycetes was quantitatively analyzed by means of dry weight loss of wood specimens. Furthermore, the preventative effect of the selected Trichoderma spp. in combination with four Cu-based preservatives was also examined by mass loss and histological changes in the wood specimens. Trichoderma harzianum (T-720) was considered the biocontrol agent with higher antagonistic potential to colonize Cu-rich environments (up to 0.1% CuSO4 amended medium). T. harzianum demonstrated significant preventative effect on wood specimens against four wood destroying basidiomycetes. The combined effect of T. harzianum and Cu-based wood preservatives demonstrated that after 9 months incubation with two wood destroying basidiomycetes, wood specimens treated with 3.8 kg m-3 copper-chromium had weight losses between 55-65%, whereas containers previously treated with T. harzianum had significantly lower weight losses (0-25%). Histological studies on one of the wood destroying basidiomycetes revealed typical decomposition of wood cells by brown-rot fungi in Cu-impregnated samples, that were notably absent in wood specimens previously exposed to T

Integrated control of wood destroying basidiomycetes combining Cu-based wood preservatives and Trichoderma spp.

Directory of Open Access Journals (Sweden)

Javier Ribera

Full Text Available The production of new generation of wood preservatives (without addition of a co-biocide in combination with an exchange of wood poles on identical sites with high fungal inoculum, has resulted in an increase of premature failures of wood utility poles in the last decades. Wood destroying basidiomycetes inhabiting sites where poles have been installed, have developed resistance against wood preservatives. The objective of the in vitro studies was to identify a Trichoderma spp. with a highly antagonistic potential against wood destroying basidiomycetes that is capable of colonizing Cu-rich environments. For this purpose, the activity of five Trichoderma spp. on Cu-rich medium was evaluated according to its growth and sporulation rates. The influence of the selected Trichoderma spp. on wood colonization and degradation by five wood destroying basidiomycetes was quantitatively analyzed by means of dry weight loss of wood specimens. Furthermore, the preventative effect of the selected Trichoderma spp. in combination with four Cu-based preservatives was also examined by mass loss and histological changes in the wood specimens. Trichoderma harzianum (T-720 was considered the biocontrol agent with higher antagonistic potential to colonize Cu-rich environments (up to 0.1% CuSO4 amended medium. T. harzianum demonstrated significant preventative effect on wood specimens against four wood destroying basidiomycetes. The combined effect of T. harzianum and Cu-based wood preservatives demonstrated that after 9 months incubation with two wood destroying basidiomycetes, wood specimens treated with 3.8 kg m-3 copper-chromium had weight losses between 55-65%, whereas containers previously treated with T. harzianum had significantly lower weight losses (0-25%. Histological studies on one of the wood destroying basidiomycetes revealed typical decomposition of wood cells by brown-rot fungi in Cu-impregnated samples, that were notably absent in wood specimens

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 (...

Fuel Wood Consumption and Species Degradation in South-Western Nigeria: The Ecological Relevance

Directory of Open Access Journals (Sweden)

Orimoogunje Oluwagbenga O.I.

2015-01-01

Full Text Available The continuous dependence of man on fuel and service wood has resulted in serious degradation of the fragile forest ecosystem. Therefore, this study evaluated the sources and patterns of fuel wood and examined the rate of consumption in the study area. This was with the aim to assess the ecological implications of fuelwood consumption on species degradation. The study utilized both, primary and secondary data. Information was extracted from topographic map on the scale of 1: 50,000 and satellites imageries that cover the study area. Questionnaire administration, field observation and weight measurement of fuel wood were carried out. The results showed that the sources of fuel wood for domestic cooking were forest, nearby bush and abandoned farm while the sources of domestic energy were fuel wood (61.17%, charcoal (27%, kerosene (10%, electricity (1.33% and gas (0.5%. Fuel wood for small scale industries were: forest (49.23%, farmland (34.62 and fallow land (16.15%. The trend of fuel wood consumption was on the high side from 1995 to 2011, it was 58% in 1995, 70% in 2000, 82% in 2005 and 92% in 2010 and 2011 respectively. Many valuable economic tree species such as Triplochiton scleroxylon, Nesogordonia papaverifera, and Cordia spp. are near their extinction. Animals such as antelope, wolf and fox are going into extinction while monkey, grasscutter, hare, rabbit were endemic in the study area. The study concluded that the patterns of fuel wood use and fuel wood saturation presents a great danger for biodiversity products and services.

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.

Aspidoscelis deppii (Black-bellied Racerunner). Predation by Great Egrets

Science.gov (United States)

Reynolds, Robert P.; Whatton, James F.; Gebhard, Christina A.

2014-01-01

Aspidoscelis deppii) is widely distributed from Veracruz and Michoacan, Mexico to Costa Rica (Köhler et al. 2006. The Amphibians and Reptiles of El Salvador. Krieger Publishing Co., Malabar, Florida. 238 pp.). Neotropical lizards are abundant and common prey to all classes of terrestrial vertebrates, and bird predation of lizards is well known.

Potential risk to wood storks (Mycteria americana) from mercury in Carolina Bay fish

International Nuclear Information System (INIS)

Brant, H.A.; Jagoe, C.H.; Snodgrass, J.W.; Bryan, A.L.; Gariboldi, J.C.

2002-01-01

Fish mercury levels from some Carolina bays pose risk to wood stork. - Carolina bays are freshwater wetlands that serve as important feeding habitats for the endangered wood stork (Mycteria americana). Water levels in these bays fluctuate greatly and tend to be acidic and rich in dissolved organic carbon (DOC), factors that favor mercury (Hg) methylation and bioaccumulation in fish. To assess potential risks to wood storks consuming mercury contaminated fish in bays, we sampled fish from 10 bays on the Savannah River Site (SRS), South Carolina, an area with documented use by wood storks. Whole body mercury concentrations in 258 fishes of three species (Erimyzon sucetta, Acantharchus pomotis and Esox americanus) commonly consumed by wood storks were determined. Risk factors for nestlings and free-ranging adults were calculated using published no and lowest observable adverse effect concentration (NOAEC and LOAEC) values for birds. Fish from higher trophic levels and those from wetlands with relatively shallow maximum depths and fluctuating water levels were more likely to exceed NOAEC and LOAEC values. Calculation of exposure rates of nestling wood storks indicated they are at highest risk during the first 10 days of the nestling period. These calculations suggest that there is potential concern for wood storks foraging in relatively shallow bays with fluctuating water levels, even though there is no obvious local source of mercury to these wetlands

What Next for Wood Construction/Demolition Debris?

OpenAIRE

Martin A. Hubbe

2014-01-01

Residents in localities throughout the world voluntarily participate in the routine recycling of household wastes, such as paper, metals, and plastics containers. But when a house in their neighborhood gets built or torn down, most of the debris – including wood waste – gets landfilled. Such a waste of material suggests that there are opportunities to add value to these under-utilized resources. The great variability, as well as contamination, pose major challenges. It is recommended that rec...

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....

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.

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.

Highly filled biocomposites based on ethylene-vinyl acetate copolymer and wood flour

Science.gov (United States)

Shelenkov, P. G.; Pantyukhov, P. V.; Popov, A. A.

2018-05-01

Recently, there is a great interest in the world to biodegradable materials based on synthetic polymers in a composition with natural fillers. Highly filled polymer composite materials based on various grades of synthetic block copolymer of ethylene vinyl acetate with wood flour were under investigation. Five grades of ethylene-vinyl acetate copolymer differing in the content of vinyl acetate groups and a melt flow index were used in this work in order to find the best one for highly filled biocomposites. Wood flour content in biocomposites was 50, 60, 70 weight %. The rheological and physico-mechanical characteristics of the resulting biocomposites were studied.

Identification and Evaluation of Oncoming Changes of Wood and Paper Industries of the Country

Directory of Open Access Journals (Sweden)

A.Akbar Bahmani

2012-01-01

Full Text Available Studying and rating of oncoming challenges of the wood and paper industries of the country can create a delicate attitude for policy makers and investors of these valuable industries. This study by the aim of identification and evaluation of wood and paper industries challenges with scientific and authentic method of likert spectra scale was done is 2010. Present challenges of wood and paper industries were detected by literature review and consulting with experts and academician and a number of manufacturing unites of wood and paper industries and query was designed. Intended data and statistics obtained from experts of wood and paper industries were compared and analyzed by likert scale spectra. The results showed that of 24 examined challenges, shortage of raw material, lake of long, compressive and applied prospective, existence of great gap between the university and industrial units and wearied and aged machinery are among the most important. Finally the identified challenges were submitted to the authorities for helping the economy of the country as well as causing the prosperity and budding of these industries.

"In the Footsteps of Alexander the Great" PBS Series. Teacher's Guide.

Science.gov (United States)

Corporation for Public Broadcasting, Washington, DC.

This teacher's guide correlates with the Public Broadcasting Service (PBS) television series "In the Footsteps of Alexander the Great" hosted by historian Michael Wood. The four episodes of the series are entitled: "Son of God"; "Lord of Asia"; "Across the Hindu Kush"; and "To the Ends of the…

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 ...

Chesapeake Bay Future Conditions Report. Volume 11. Biota.

Science.gov (United States)

1977-12-01

vertebrates , the cattle egret , glossy ibis and nutr ia are highly success ful new- comers , with an ecological impact yet to be assessed. Eurasian wa...Horned grebe Podiceps aur i tus Protected Cattle egret Bubulcus ibis Protected Great blue heron Ardea herodias Protected Glossy ibis Plegadis...xanthid crabs but not R. harrisii. Non-nutritional Role of Other Species Fertilization: Loxothylacus castrates the sexual organs. Appendix 15 119

Soil-wood interactions

NARCIS (Netherlands)

Wal, van der Annemieke; klein Gunnewiek, Paulien; Boer, de Wietse

2017-01-01

Wood-inhabiting fungi may affect soil fungal communities directly underneath decaying wood via their exploratory hyphae. In addition, differences in wood leachates between decaying tree species may influence soil fungal communities. We determined the composition of fungi in 4-yr old decaying logs

Wood energy-commercial applications

Science.gov (United States)

Kennel, R. P.

1978-01-01

Wood energy is being widely investigated in many areas of the country because of the many obvious benefits of wood fuel such as the low price per million Btus relative to coal, oil, and gas; the wide availability of noncommercial wood and the proven ability to harvest it; established technology which is reliable and free of pollution; renewable resources; better conservation for harvested land; and the potential for jobs creation. The Southeastern United States has a specific leadership role in wood energy based on its established forest products industry experience and the potential application of wood energy to other industries and institutions. Significant questions about the widespread usage of wood energy are being answered in demonstrations around the country as well as the Southeast in areas of wood storage and bulk handling; high capitalization costs for harvesting and combustion equipment; long term supply and demand contracts; and the economic feasibility of wood energy outside the forest products industry.

Wood fuel from early thinning and plantation cleaning. Summary of an international review

International Nuclear Information System (INIS)

Puttock, D.

1998-01-01

This paper summaries the results of an international of wood fuel from early thinning and plantation cleaning. The economic and biological benefits from early thinning have been well documented. However, removing forest biomass during early stages of stand development from sites which are low in one or more nutrients may contribute a loss of nutrients and organic matter. Depending on the pre-thinning density and the thinning intensity, the potential yield of wood fuel from early thinning may be as much as 79 dry tons per hectare. Thus, wood fuel from the thinnings could be an important source of revenue to forest owners and would contribute to domestic energy requirements. Motor-manual felling predominates in early thinning, mainly due to the lack of appropriate technology for thinning small trees. However, the productivity of motor-manual felling is greatly affected by the initial stand density and declines dramatically at densities greater than 10 000 stems per ha. Under these conditions, purpose-built wood fuel harvesters with small-tree harvesting capability offer the greatest potential for increasing felling productivity and reducing the cost of wood fuel. The cost of wood fuel from early thinnings varies widely between countries from USD 25.00 - 87.50 per dry ton depending on stand conditions, harvesting system, transport distance, domestic tax rates, and stumpage prices. At the low end of this range, wood fuel chips from early thinning are competitive with wood fuel produced from mill waste, the residues from clearfell operations, or from later thinnings

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.

Wood density and anatomy of three Eucalyptus species: implications for hydraulic conductivity

International Nuclear Information System (INIS)

Barotto, A.J.; Monteoliva, S.; Gyenge, J.; Martínez-Meier, A.; Moreno, K.; Tesón, N.; Fernández, M.E.

2017-01-01

Aim of the study: To characterize wood anatomical traits of three Eucalyptus species that differ in wood density and ecological requirements, and to examine the relationships between some anatomical features, wood density, and theoretical xylem hydraulic conductivity (Ks). Area of study: We analyzed 86 trees from three sites of Argentina (Entre Ríos and Buenos Aires Provinces). Methods: The sampled trees were Eucalyptus globulus, E. grandis and E. viminalis ranging from 11 to 15 years old. One stem disc was cut from each tree to determine wood density and identify quantitative anatomical features of vessels and fibers. Vessel composition (S, size - to-number ratio, a measure of vessel size distribution) and lumen fraction (F, the total sapwood area available for water transport) were estimated. Results: E. grandis, the species with the highest growth rates, presented the highest theoretical Ks. This was associated with anatomical features such as a high density of wide vessels resulting in high F. On the other hand, E. viminalis, the species with the lowest growth rates and highest resistance to environmental stress, showed lower Ks as a result of a low density of wide vessels. These two species differed not only greatly in wood density but also in fiber characteristics. In the case of E. globulus, vessels were relatively narrow, which resulted in the lowest theoretical Ks, fibers were small, and wood density intermediate. Research highlights: F had greater influence on Ks than S. The anatomical characteristics and wood density could only partly explain the differential growth or resistance to stress of the studied species.

Wood density and anatomy of three Eucalyptus species: implications for hydraulic conductivity

Directory of Open Access Journals (Sweden)

Antonio J. Barotto

2017-05-01

Full Text Available Aim of the study: To characterize wood anatomical traits of three Eucalyptus species that differ in wood density and ecological requirements, and to examine the relationships between some anatomical features, wood density, and theoretical xylem hydraulic conductivity (Ks. Area of study: We analyzed 86 trees from three sites of Argentina (Entre Ríos and Buenos Aires Provinces. Methods: The sampled trees were Eucalyptus globulus, E. grandis and E. viminalis ranging from 11 to 15 years old. One stem disc was cut from each tree to determine wood density and identify quantitative anatomical features of vessels and fibers. Vessel composition (S, size - to-number ratio, a measure of vessel size distribution and lumen fraction (F, the total sapwood area available for water transport were estimated. Results: E. grandis, the species with the highest growth rates, presented the highest theoretical Ks. This was associated with anatomical features such as a high density of wide vessels resulting in high F. On the other hand, E. viminalis, the species with the lowest growth rates and highest resistance to environmental stress, showed lower Ks as a result of a low density of wide vessels. These two species differed not only greatly in wood density but also in fiber characteristics. In the case of E. globulus, vessels were relatively narrow, which resulted in the lowest theoretical Ks, fibers were small, and wood density intermediate. Research highlights: F had greater influence on Ks than S. The anatomical characteristics and wood density could only partly explain the differential growth or resistance to stress of the studied species.

Wood density and anatomy of three Eucalyptus species: implications for hydraulic conductivity

Energy Technology Data Exchange (ETDEWEB)

Barotto, A.J.; Monteoliva, S.; Gyenge, J.; Martínez-Meier, A.; Moreno, K.; Tesón, N.; Fernández, M.E.

2017-11-01

Aim of the study: To characterize wood anatomical traits of three Eucalyptus species that differ in wood density and ecological requirements, and to examine the relationships between some anatomical features, wood density, and theoretical xylem hydraulic conductivity (Ks). Area of study: We analyzed 86 trees from three sites of Argentina (Entre Ríos and Buenos Aires Provinces). Methods: The sampled trees were Eucalyptus globulus, E. grandis and E. viminalis ranging from 11 to 15 years old. One stem disc was cut from each tree to determine wood density and identify quantitative anatomical features of vessels and fibers. Vessel composition (S, size - to-number ratio, a measure of vessel size distribution) and lumen fraction (F, the total sapwood area available for water transport) were estimated. Results: E. grandis, the species with the highest growth rates, presented the highest theoretical Ks. This was associated with anatomical features such as a high density of wide vessels resulting in high F. On the other hand, E. viminalis, the species with the lowest growth rates and highest resistance to environmental stress, showed lower Ks as a result of a low density of wide vessels. These two species differed not only greatly in wood density but also in fiber characteristics. In the case of E. globulus, vessels were relatively narrow, which resulted in the lowest theoretical Ks, fibers were small, and wood density intermediate. Research highlights: F had greater influence on Ks than S. The anatomical characteristics and wood density could only partly explain the differential growth or resistance to stress of the studied species.

Who's Counting Dead Wood ?

OpenAIRE

Woodall, C. W.; Verkerk, H.; Rondeux, Jacques; Ståhl, G.

2009-01-01

Dead wood in forests is a critical component of biodiversity, carbon and nutrient cycles, stand structure, and fuel loadings. Until recently, very few countries have conducted systematic inventories of dead wood resources across their forest lands. This may be changing as an increasing number of countries implement dead wood inventories. A recent survey looks at the status and attributes of forest dead wood inventories in over 60 countries. About 13 percent of countries inventory dead wood gl...

Classification of CITES-listed and other neotropical Meliaceae wood images using convolutional neural networks.

Science.gov (United States)

Ravindran, Prabu; Costa, Adriana; Soares, Richard; Wiedenhoeft, Alex C

2018-01-01

The current state-of-the-art for field wood identification to combat illegal logging relies on experienced practitioners using hand lenses, specialized identification keys, atlases of woods, and field manuals. Accumulation of this expertise is time-consuming and access to training is relatively rare compared to the international demand for field wood identification. A reliable, consistent and cost effective field screening method is necessary for effective global scale enforcement of international treaties such as the Convention on the International Trade in Endagered Species (CITES) or national laws (e.g. the US Lacey Act) governing timber trade and imports. We present highly effective computer vision classification models, based on deep convolutional neural networks, trained via transfer learning, to identify the woods of 10 neotropical species in the family Meliaceae, including CITES-listed Swietenia macrophylla , Swietenia mahagoni , Cedrela fissilis , and Cedrela odorata . We build and evaluate models to classify the 10 woods at the species and genus levels, with image-level model accuracy ranging from 87.4 to 97.5%, with the strongest performance by the genus-level model. Misclassified images are attributed to classes consistent with traditional wood anatomical results, and our species-level accuracy greatly exceeds the resolution of traditional wood identification. The end-to-end trained image classifiers that we present discriminate the woods based on digital images of the transverse surface of solid wood blocks, which are surfaces and images that can be prepared and captured in the field. Hence this work represents a strong proof-of-concept for using computer vision and convolutional neural networks to develop practical models for field screening timber and wood products to combat illegal logging.

GRO/EGRET data analysis software: An integrated system of custom and commercial software using standard interfaces

Science.gov (United States)

Laubenthal, N. A.; Bertsch, D.; Lal, N.; Etienne, A.; Mcdonald, L.; Mattox, J.; Sreekumar, P.; Nolan, P.; Fierro, J.

1992-01-01

The Energetic Gamma Ray Telescope Experiment (EGRET) on the Compton Gamma Ray Observatory has been in orbit for more than a year and is being used to map the full sky for gamma rays in a wide energy range from 30 to 20,000 MeV. Already these measurements have resulted in a wide range of exciting new information on quasars, pulsars, galactic sources, and diffuse gamma ray emission. The central part of the analysis is done with sky maps that typically cover an 80 x 80 degree section of the sky for an exposure time of several days. Specific software developed for this program generates the counts, exposure, and intensity maps. The analysis is done on a network of UNIX based workstations and takes full advantage of a custom-built user interface called X-dialog. The maps that are generated are stored in the FITS format for a collection of energies. These, along with similar diffuse emission background maps generated from a model calculation, serve as input to a maximum likelihood program that produces maps of likelihood with optional contours that are used to evaluate regions for sources. Likelihood also evaluates the background corrected intensity at each location for each energy interval from which spectra can be generated. Being in a standard FITS format permits all of the maps to be easily accessed by the full complement of tools available in several commercial astronomical analysis systems. In the EGRET case, IDL is used to produce graphics plots in two and three dimensions and to quickly implement any special evaluation that might be desired. Other custom-built software, such as the spectral and pulsar analyses, take advantage of the XView toolkit for display and Postscript output for the color hard copy. This poster paper outlines the data flow and provides examples of the user interfaces and output products. It stresses the advantages that are derived from the integration of the specific instrument-unique software and powerful commercial tools for graphics and

Molecular Dynamics of Water in Wood Studied by Fast Field Cycling Nuclear Magnetic Resonance Relaxometry

Directory of Open Access Journals (Sweden)

Xinyu Li

2016-01-01

Full Text Available Water plays a very important role in wood and wood products. The molecular motion of water in wood is susceptible to thermal activation. Thermal energy makes water molecules more active and weakens the force between water and wood; therefore, the water molecules dynamic properties are greatly influenced. Molecular dynamics study is important for wood drying; this paper therefore focuses on water molecular dynamics in wood through fast field cycling nuclear magnetic resonance relaxometry techniques. The results show that the spin-lattice relaxation rate decreases with the Larmor frequency. Nuclear magnetic resonance dispersion profiles at different temperatures could separate the relaxation contribution of water in bigger pores and smaller pores. The T1 distribution from wide to narrow at 10 MHz Larmor frequency reflects the shrinkage of pore size with the higher temperature. The dependence of spin-lattice relaxation rate on correlation time for water molecular motion based on BPP (proposed by Bloembergen, Purcell, and Pound theory shows that water correlation time increases with higher temperature, and its activation energy, calculated using the Arrhenius transformation equation, is 9.06±0.53 kJ/mol.

Filling behaviour of wood plastic composites

Science.gov (United States)

Duretek, I.; Lucyshyn, T.; Holzer, C.

2017-01-01

Wood plastic composites (WPC) are a young generation of composites with rapidly growing usage within the plastics industry. The advantages are the availability and low price of the wood particles, the possibility of partially substituting the polymer in the mixture and sustainable use of the earth’s resources. The current WPC products on the market are to a large extent limited to extruded products. Nowadays there is a great interest in the market for consumer products in more use of WPC as an alternative to pure thermoplastics in injection moulding processes. This work presents the results of numerical simulation and experimental visualisation of the mould filling process in injection moulding of WPC. The 3D injection moulding simulations were done with the commercial software package Autodesk® Moldflow® Insight 2016 (AMI). The mould filling experiments were conducted with a box-shaped test part. In contrast to unfilled polymers the WPC has reduced melt elasticity so that the fountain flow often does not develop. This results in irregular flow front shapes in the moulded part, especially at high filler content.

Occurrence patterns of dead wood and wood-dependent lichens in managed boreal forest landscapes

OpenAIRE

Svensson, Måns

2013-01-01

Dead wood is a key resource for biodiversity, on which thousands of forest organisms are dependent. Because of current forest management, there has been a large-scale change in dead wood amounts and qualities, and consequently, many wood-dependent species are threatened. The general aim of this thesis is to increase our understanding of habitat requirements and occurrence patterns of wood-dependent lichens in managed, boreal forest landscapes. We surveyed dead wood and wood-dependent lichens ...

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)

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...

Food, reproductive success and multiple breeding in the Great Tit Parus major

NARCIS (Netherlands)

Verboven, Nanette; Tinbergen, Joost M.; Verhulst, Simon

2001-01-01

We studied the reproductive success of facultatively double brooded Great Tits Parus major in relation to (seasonal) variation in abundance of their main food supply: caterpillars in Oak Quercus robur. Data were collected in two mixed woods (Vlieland and Hoge Veluwe, from 1985-1996). The caterpillar

The decay of wood in landfills in contrasting climates in Australia

Energy Technology Data Exchange (ETDEWEB)

Ximenes, Fabiano, E-mail: fabiano.ximenes@dpi.nsw.gov.au [Forest Science, Agriculture NSW, New South Wales Department of Primary Industries, Level 12, 10 Valentine Ave, Parramatta, NSW 2150 (Australia); Björdal, Charlotte [Department of Conservation, Gothenburg University, Guldhedsgatan 5A, Box 130, SE-405 30 Göteborg (Sweden); Cowie, Annette [NSW Department of Primary Industries, Beef Industry Centre, Trevenna Rd., University of New England, Armidale, NSW 2351 (Australia); Barlaz, Morton [Dept. of Civil, Construction, & Environmental Eng., North Carolina State University, Box 7908, Raleigh, NC 27695-7908 (United States)

2015-07-15

from Cairns indicates that those wood types were more susceptible to biodegradation. Microscopic analyses revealed that most decay patterns observed in samples analysed from Sydney were consistent with aerobic fungal decay. Only a minor portion of the microbial decay was due to erosion bacteria active in anaerobic/near anaerobic environments. The findings of this study strongly suggest that models that adopt current accepted default factors for the decay of wood in landfills greatly overestimate methane emissions.

The decay of wood in landfills in contrasting climates in Australia

International Nuclear Information System (INIS)

Ximenes, Fabiano; Björdal, Charlotte; Cowie, Annette; Barlaz, Morton

2015-01-01

from Cairns indicates that those wood types were more susceptible to biodegradation. Microscopic analyses revealed that most decay patterns observed in samples analysed from Sydney were consistent with aerobic fungal decay. Only a minor portion of the microbial decay was due to erosion bacteria active in anaerobic/near anaerobic environments. The findings of this study strongly suggest that models that adopt current accepted default factors for the decay of wood in landfills greatly overestimate methane emissions

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.

Wood Smoke

Science.gov (United States)

Smoke is made up of a complex mixture of gases and fine, microscopic particles produced when wood and other organic matter burn. The biggest health threat from wood smoke comes from fine particles (also called particulate matter).

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....

Ionizing radiation and a wood-based biorefinery

International Nuclear Information System (INIS)

Driscoll, Mark S.; Stipanovic, Arthur J.; Cheng, Kun; Barber, Vincent A.; Manning, Mellony; Smith, Jennifer L.; Sundar, Smith

2014-01-01

Woody biomass is widely available around the world. Cellulose is the major structural component of woody biomass and is the most abundant polymer synthesized by nature, with hemicellulose and lignin being second and third. Despite this great abundance, woody biomass has seen limited application outside of the paper and lumber industries. Its use as a feedstock for fuels and chemicals has been limited because of its highly crystalline structure, inaccessible morphology, and limited solubility (recalcitrance). Any economic use of woody biomass for the production of fuels and chemicals requires a “pretreatment” process to enhance the accessibility of the biomass to enzymes and/or chemical reagents. Electron beams (EB), X-rays, and gamma rays produce ions in a material which can then initiate chemical reactions and cleavage of chemical bonds. Such ionizing radiation predominantly scissions and degrades or depolymerizes both cellulose and hemicelluloses, less is known about its effects on lignin. This paper discusses how ionizing radiation can be used to make a wood-based biorefinery more environmentally friendly and profitable for its operators. - Highlights: • Ionizing radiation reduces the crystallinity of cellulose. • Ionizing radiation reduces cellulose's degree of polymerization. • The amount and rate of enzymatic hydrolysis of lignocellulosic materials, including wood, are increased with increasing radiation dose. • Wood and other lignocellulosic materials have the potential to be a renewable material for the production of chemicals and fuels

An anhinga shows its iridescent plumage

Science.gov (United States)

2000-01-01

The greenish iridescence of a male Anhinga nearly blends into the green vegetation behind it on the grounds of the Kennedy Space Center. The mostly black-bodied bird is also known as a 'snakebird' because, when swimming, only its head and long, slender neck are visible above water. The anhinga inhabits freshwater ponds and swamps with thick vegetation and ranges the Atlantic and Gulf coasts from North Carolina to Texas, the Mississippi Valley north to Arkansas and Tennessee, and south to southern South America. The Center shares a boundary with the Merritt Island National Wildlife Refuge, which encompasses 92,000 acres that are a habitat for more than 331 species of birds, 31 mammals, 117 fishes, and 65 amphibians and reptiles. The marshes and open water of the refuge provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds, as well as a variety of insects.

Black-necked stilts share nesting in the Merritt Island National Wildlife Refuge

Science.gov (United States)

1999-01-01

A black-necked stilt waits near its nesting mate nest in the Merritt Island National Wildlife Refuge, which shares a boundary with Kennedy Space Center. Stilts usually produce three or four brown-spotted buff eggs in a shallow depression lined with grass or shell fragments. In the nesting season they are particularly agressive. Stilts are identified by a distinct head pattern of black and white, very long red legs, and straight, very thin bill. Their habitat is salt marshes and shallow coastal bays from Delaware and northern South America in the East, and freshwater marshes from Oregon and Saskatchewan to the Gulf Coast. The 92,000-acre wildlife refuge is a habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles. The marshes and open water of the refuge also provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds.

How spectroscopy and microspectroscopy of degraded wood contribute to understand fungal wood decay.

Science.gov (United States)

Fackler, Karin; Schwanninger, Manfred

2012-11-01

Nuclear magnetic resonance, mid and near infrared, and ultra violet (UV) spectra of wood contain information on its chemistry and composition. When solid wood samples are analysed, information on the molecular structure of the lignocellulose complex of wood e.g. crystallinity of polysaccharides and the orientation of the polymers in wood cell walls can also be gained. UV and infrared spectroscopy allow also for spatially resolved spectroscopy, and state-of-the-art mapping and imaging systems have been able to provide local information on wood chemistry and structure at the level of wood cells (with IR) or cell wall layers (with UV). During the last decades, these methods have also proven useful to follow alterations of the composition, chemistry and physics of the substrate wood after fungi had grown on it as well as changes of the interactions between the wood polymers within the lignocellulose complex caused by decay fungi. This review provides an overview on how molecular spectroscopic methods could contribute to understand these degradation processes and were able to characterise and localise fungal wood decay in its various stages starting from the incipient and early ones even if the major share of research focussed on advanced decay. Practical issues such as requirements in terms of sample preparation and sample form and present examples of optimised data analysis will also be addressed to be able to detect and characterise the generally highly variable microbial degradation processes within their highly variable substrate wood.

Growth of high-density ZnO nanorods on wood with enhanced photostability, flame retardancy and water repellency

Science.gov (United States)

Kong, Lizhuo; Tu, Kunkun; Guan, Hao; Wang, Xiaoqing

2017-06-01

Zinc oxide (ZnO) nanorod arrays were successfully assembled on the wood surface in situ via a two-step process consisting of formation of ZnO seeds and subsequent crystal growth under hydrothermal conditions at a low temperature. The morphology and crystalline structure of the formed ZnO nanorods were studied by field-emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). Highly dense and uniform arrays of ZnO nanorods with well-defined hexagonal facets were generated on the wood surface by tuning the concentration of the ZnO growth solution during the hydrothermal treatment. Accelerated weathering tests indicated that the assembled ZnO nanorod arrays were highly protective against UV radiation and greatly enhanced the photostability of the coated wood. Meanwhile, the ZnO nanorod-coated wood can withstand continuous exposure to flame with only minor smoldering in contrast with the pristine wood catching fire easily and burning rapidly. Moreover, when further modified with low-surface-energy stearic acid, the ZnO nanorod decorated wood surface can be transformed into a superhydrophobic surface, with a water contact angle (CA) of ∼154°. Such ZnO nanorod-modified woods with enhanced photostability, flame retardancy and water repellency offer an interesting alternative to conventional wood preservation strategies, highlighting their potential applications in some novel wood products.

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/

Factors affecting the laser processing of wood, 2: Effects of material parameters on machinability

International Nuclear Information System (INIS)

Arai, T.; Hayashi, D.

1994-01-01

Material parameters of wood were investigated. Factors relating to the workpiece include cutting direction, specific gravity, and components of the wood such as resin-like materials. Also studies of the effects of irregular tissue on machinability were made. The interactions between laser beam and materials are often greatly complex. They depend on the characteristics of the laser beam, the thermal constants of the woods, and the optical surface properties of the woods. Therefore, high quality beam mode and carefully selected materials were used. The following laser cutting properties became clear after studying the experimental results. Slow speed cutting and softwoods make slight differences, regarding cutting section and fiber direction. However, it can beconsidered that there is not very much change except in cross-section. Because of the high power density of laser, cutting speed makes no big difference. The irregular tissue of wood cannot maintain normal cutting speed and accuracy. The factor of genuine density eta, which is thought to be entirely independent of each specific gravity, is definedas the concept of density in general. It can be obtained by applying a simple rule, that is, the eta is the ratio of r(u)/rho(s) where rho(s) is the wood substance as the characteristic value of wood, and r(u)is specific gravity. An experimental formula shows that the depth of cut decreases in proportion to the value of eta. However, in the strict sense of the word, data of wood material as a natural resources mustbe treated qualitatively, because there are deviations from regularity due to various reasons. (author)

Life cycle environmental impacts of different construction wood waste and wood packaging waste processing methods

OpenAIRE

Manninen, Kaisa; Judl, Jáchym; Myllymaa, Tuuli

2016-01-01

This study compared the life cycle environmental impacts of different wood waste processing methods in three impact categories: climate impact, acidification impacts and eutrophication impacts. The wood waste recovery methods examined were the use of wood waste in terrace boards made out of wood composite which replace impregnated terrace boards, incineration of wood waste in a multi-fuel boiler instead of peat and the use of wood waste in the production of particleboard in either Finland or ...

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.

USE OF AMAZONIAN SPECIES FOR AGING DISTILLED BEVERAGES: PHYSICAL AND CHEMICAL WOOD ANALYSIS

Directory of Open Access Journals (Sweden)

Jonnys Paz Castro

2015-06-01

Full Text Available The process of storing liquor in wooden barrels is a practice that aims to improve the sensory characteristics, such as color, aroma and flavor, of the beverage. The quality of the liquor stored in these barrels depends on wood characteristics such as density, permeability, chemical composition, anatomy, besides the wood heat treatment used to fabricate the barrels. Brazil has a great diversity of forests, mainly in the north, in the Amazon. This region is home to thousands of tree species, but is limited to the use of only a few native species to store liquors. The objective of this study was to determine some of the physical and chemical characteristics for four Amazon wood species. The results obtained in this study will be compared with others from woods that are traditionally used for liquor storage. The species studied were angelim-pedra (Hymenolobium petraeum Ducke cumarurana (Dipteryx polyphylla (Huber Ducke, jatobá (Hymenaea courbaril L. and louro-vermelho (Nectandra rubra (Mez CK Allen. The trees were collected from Precious Woods Amazon Company forest management area, in Silves, Amazonas. Analyzes such as: concentration of extractives, lignin amount, percentage of minerals (ash and tannin content, density, elemental analysis (CHNS-O and thermal analysis were done. It was observed that the chemical composition (lignin, holocellulose and elemental analysis (percentage of C, H, N and O of the woods have significant differences. The jatobá wood presented higher tannin content, and in the thermal analysis, was that which had the lowest mass loss.

Many Roles of Wood Adhesives

Science.gov (United States)

Charles R. Frihart

2014-01-01

Although wood bonding is one of the oldest applications of adhesives, going back to early recorded history (1), some aspects of wood bonds are still not fully understood. Most books in the general area of adhesives and adhesion do not cover wood bonding. However, a clearer understanding of wood bonding and wood adhesives can lead to improved products. This is important...

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.

Characterizing, modelling and optimizing the sound absorption of wood wool cement boards (WWCB)

NARCIS (Netherlands)

Botterman, B.; Hornikx, M.C.J.; Doudart de la Grée, G.C.H.; Yu, Q.; Brouwers, H.J.H.

2016-01-01

The present article aims to characterize and, by using impedance models, predict the sound absorption of wood wool cement boards (WWCB). The main challenge lies in the inhomogeneity of the WWCB; the samples taken from different commercial boards do not only greatly differ in density, but also in

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)

Growth and Wood/Bark Properties of Abies faxoniana Seedlings as Affected by Elevated CO2

Institute of Scientific and Technical Information of China (English)

Yun-Zhou Qiao; Yuan-Bin Zhang; Kai-Yun Wang; Qian Wang; Qi-Zhuo Tian

2008-01-01

Growth and wood and bark properties of Abies faxoniana seedlings after one year's exposure to elevated CO2 concentration (ambient + 350 (=1= 25) μmol/mol) under two planting densities (28 or 84 plants/mz) were investigated in closed-top chambers. Tree height, stem diameter and cross-sectional area, and total biomass were enhanced under elevated CO2 concentration, and reduced under high planting density. Most traits of stem bark were improved under elevated CO2 concentration and reduced under high planting density. Stem wood production was significantly increased in volume under elevated CO2 concentration under both densities, and the stem wood density decreased under elevated CO2 concentration and increased under high planting density. These results suggest that the response of stem wood and bark to elevated CO2 concentration is density dependent. This may be of great importance in a future CO2 enriched world in natural forests where plant density varies considerably. The results also show that the bark/wood ratio in diameter, stem cross-sectional area and dry weight are not proportionally affected by elevated CO2 concentration under the two contrasting planting densities. This indicates that the response magnitude of stem bark and stem wood to elevated CO2 concentration are different but their response directions are the same.

Wood construction under cold climate

DEFF Research Database (Denmark)

Wang, Xiaodong; Hagman, Olle; Sundqvist, Bror

2014-01-01

As wood constructions increasingly use engineered wood products worldwide, concerns arise about the integrity of the wood and adhesives system. The glueline stability is a crucial issue for engineered wood application, especially under cold climate. In this study, Norway spruce (Picea abies...... 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...... specimens need to be tested in further work to more completely present the issue. The EN 301 and EN 302 may need to be specified based on wood species....

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.)

Controversy. The wood war

International Nuclear Information System (INIS)

James, O.

2010-01-01

The author comments the conflict emerging in France between industries exploiting wood for construction and those exploiting it as a heating material for power generation. The first ones accuse the others to steal their raw material, to pull the prices up, and to destabilize the sector. This conflict takes place notably around sawmill wastes which are used either by wood panel fabricators or by wood pellets producers. Both sectors are claiming they are creating more jobs than the other. The French forest indeed offers good opportunities for both sectors, but other countries which are lacking forest surfaces, are buying wood in France. Several issues are matter of discussion: burning wood seems to go against the reduction of greenhouse gas emissions, subsidies awarded to big heater projects. The situation of the wood sector in Austria, Finland and Poland is briefly presented

Wood torrefaction. Pilot tests and utilisation prospects

Energy Technology Data Exchange (ETDEWEB)

Wilen, C.; Jukola, P.; Jarvinen, T.; Sipila, K. [VTT Technical Reseach Centre of Finland, Espoo (Finland); Verhoeff, F.; Kiel, J. [Energy research Centre of the Netherlands, LE Petten (Netherlands)

2013-09-15

The research project 'Torrefaction of woody biomasses as energy carriers for the European markets' was carried out within the Tekes BioRefine programme in 2010-2012 and was coordinated by VTT. The main objective of the project was to create a discussion platform and collate basic information for the Finnish industrial stakeholders involved in developing torrefaction technology or planning to include torrefied biomass in their fuel supply for energy production. Given the availability of torrefaction pilot facilities in Europe, it was decided at an early phase of the national torrefaction research project not to build and operate separate pilot equipment, and thus save time and money. Experimental research was conducted in cooperation with ECN, The Netherlands. Finnish wood chips and crushed forest residue were tested at different torrefaction temperatures in the PATRIG torrefaction test rig with great success, and large quantities of torrefied wood chips and pellets were produced. CFD simulation work was carried out at VTT to investigate the feasibility of torrefied fuels to replace part of the coal. From the combustion point of view it seems feasible to replace coal by torrefied wood biomass with shares up to 50% by weight. Basic, small-scale experiments were carried out to compare torrefied wood pellets with conventional wood and straw pellets with regard to their handling and storage properties. The experiments showed that the torrefied pellets are clearly more hydrophobic than wood and straw pellets and do not disintegrate completely on exposure to water. A study on dust explosion and self-ignition characteristics indicated that the torrefied dust does not differ significantly from the normal biomass dust, but is clearly more reactive than coal dust. Commercial development of torrefaction is currently in its early phase. The current general view is that most of the demonstration plants have technical problems, which have delayed their commercial

Manufacture of wood-pellets doubles. Biowatti Oy started a wood pellet plant in Turenki

International Nuclear Information System (INIS)

Rantanen, M.

1999-01-01

Wood pellets have many advantages compared to other fuels. It is longest processed biofuel with favorable energy content. It is simple to use, transport and store. Heating with wood pellets is cheaper than with light fuel oil, and approximately as cheap as utilization of heavy fuel oil, about 110 FIM/MWh. The taxable price of wood pellets is about 550 FIM/t. Stokers and American iron stoves are equally suitable for combustion of wood pellets. Chip fueled stokers are preferred in Finland, but they are also suitable for the combustion of wood pellets. Wood pellets is an environmentally friendly product, because it does not increase the CO 2 load in the atmosphere, and its sulfur and soot emissions are relatively small. The wood pelletizing plant of Biowatti Oy in Turenki was started in an old sugar mill. The Turenki sugar mill was chosen because the technology of the closed sugar factory was suitable for production of wood pellets nearly as such, and required only by slight modifications. A press, designed for briquetting of sugar beat clippings makes the pellets. The Turenki mill will double the volume of wood pellet manufacture in Finland during the next few years. At the start the annual wood pellet production will be 20 000 tons, but the environmental permit allows the production to be increased to 70 000 tons. At first the mill uses planing machine chips as a raw material in the production. It is the most suitable raw material, because it is already dry (moisture content 8-10%), and all it needs is milling and pelletizing. Another possible raw material is sawdust, which moisture content is higher than with planing machine chips. Most of the wood pellets produced are exported e.g. to Sweden, Denmark and Middle Europe. In Sweden there are over 10 000 single-family houses using wood pellets. Biowatti's largest customer is a power plant located in Stockholm, which combusts annually about 200 000 tons of wood pellets

Reliable and non-destructive positioning of larvae of wood-destroying beetles in wood

International Nuclear Information System (INIS)

Kerner, G.; Thiele, H.; Unger, W.

1980-01-01

Living larvae of wood-destroying insects (house longhorn beetle, deathwatch) can be determined in wood by both X-ray technique and vibration measurements. For such examinations convenient commercial devices were used and tested under laboratory conditions. The methods complement each other and lead to a rationalization of the tests of wood preservatives against wood-destroying insects. It seems to be promising to apply the test methods also to timber already used for building

UV-LED Curing Efficiency of Wood Coatings

Directory of Open Access Journals (Sweden)

Véronic Landry

2015-12-01

Full Text Available Ultraviolet light emitting diodes (UV-LEDs have attracted great interest in recent years. They can be used to polymerize coatings, such as those used for prefinished wood flooring. In this project, two lamps were compared for their suitability to be used on a wood flooring finishing line: a UV-microwave and a UV-LED lamp. Low heat emission was found for the UV-LED lamp compared to the UV-microwave one. This study also reveals that the 4 W/cm2 UV-LED lamp used is not powerful enough to cure UV high solids acrylate coatings while satisfactory results can be obtained for UV water-based formulations. In fact, conversion percentages were found to be low for the high solids coatings, leaving the coatings tacky. Higher conversion percentages were obtained for the UV water-based formulations. As a result, mass loss, hardness, and scratch resistance found for the samples cured by UV-LED were closed to the ones found for the samples cured using the UV microwave lamp.

Results of the production of wood derived fuels; Puupolttoaineiden tuotantotekniikka - tutkimusalueen katsaus

Energy Technology Data Exchange (ETDEWEB)

Korpilahti, A [Metsaeteho, Helsinki (Finland)

1997-12-31

During the year 1995 there were over 30 projects concerning the production of wood derived fuels going on. Nearly half of them focused on integrated production of pulp wood and wood fuel. About in ten projects work was carried out to promote wood fuel production from logging residues. Other topics were fire wood production, production logistics and wood fuel resources. For production of fuel chips from logging residues, a new chipper truck, MOHA-SISU, was introduced. Having ability to move on terrain, and equipped with drum chipper, hook technic for interchangeable containers and a trailer, the whole production chain can be carried out by the same machine. In Mikkeli region three years of active work promoted the usage of wood fuel in a district power plant to the level of over 110 000 cubic metres of fuel chips. The production costs tend to be a little high in average, and the production chain still needs to be improved. In the field of integrated production a great stride was taken when the first pilot plant using the MASSAHAKE-method started up. Components of the production line and knowledge to operate the process have increased resulting in good performance of the plant. And even another concept for integrated production was introduced. In order to fully control the debarking of small sized trees, a production line of chain flail equipment and debarking drum followed by a chipper and screening facilities was built up. Equipment and machines for harvesting young stands in a way that increases substantially the yield of energy component are still mostly first prototypes. The development of them into well functioning, efficient tools is the most important task in integrated production

Results of the production of wood derived fuels; Puupolttoaineiden tuotantotekniikka - tutkimusalueen katsaus

Energy Technology Data Exchange (ETDEWEB)

Korpilahti, A. [Metsaeteho, Helsinki (Finland)

1996-12-31

During the year 1995 there were over 30 projects concerning the production of wood derived fuels going on. Nearly half of them focused on integrated production of pulp wood and wood fuel. About in ten projects work was carried out to promote wood fuel production from logging residues. Other topics were fire wood production, production logistics and wood fuel resources. For production of fuel chips from logging residues, a new chipper truck, MOHA-SISU, was introduced. Having ability to move on terrain, and equipped with drum chipper, hook technic for interchangeable containers and a trailer, the whole production chain can be carried out by the same machine. In Mikkeli region three years of active work promoted the usage of wood fuel in a district power plant to the level of over 110 000 cubic metres of fuel chips. The production costs tend to be a little high in average, and the production chain still needs to be improved. In the field of integrated production a great stride was taken when the first pilot plant using the MASSAHAKE-method started up. Components of the production line and knowledge to operate the process have increased resulting in good performance of the plant. And even another concept for integrated production was introduced. In order to fully control the debarking of small sized trees, a production line of chain flail equipment and debarking drum followed by a chipper and screening facilities was built up. Equipment and machines for harvesting young stands in a way that increases substantially the yield of energy component are still mostly first prototypes. The development of them into well functioning, efficient tools is the most important task in integrated production

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)

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)

Bridging the gaps: An overview of wood across time and space in diverse rivers

Science.gov (United States)

Wohl, Ellen

2017-02-01

Nearly 50 years of research focused on large wood (LW) in rivers provide a basis for understanding how wood enters rivers; how wood decays, breaks, and is transported downstream; and how at least temporarily stable wood influences channel geometry, fluxes of water, sediment, and organic matter, and the abundance and diversity of aquatic and riparian organisms. Field-based studies have led to qualitative conceptual models and to numerical stimulations of river processes involving wood. Numerous important gaps remain, however, in our understanding of wood dynamics. The majority of research on wood in rivers focuses on small- to medium-sized rivers, defined using the ratio of wood piece size to channel width as channels narrower than the locally typical wood-piece length (small) and slightly narrower than the longer wood pieces present (medium). Although diverse geographic regions and biomes are represented by one or a few studies in each region, the majority of research comes from perennial rivers draining temperate conifer forests. Regional syntheses most commonly focus on the Pacific Northwest region of North America where most of these studies originate. Consequently, significant gaps in our understanding include lack of knowledge of wood-related processes in large rivers, dryland rivers, and rivers of the high and low latitudes. Using a wood budget as an organizing framework, this paper identifies other gaps related to wood recruitment, transport, storage, and how beavers influence LW dynamics. With respect to wood recruitment, we lack information on the relative importance of mass tree mortality and transport of buried or surficial downed wood from the floodplain into the channel in diverse settings. Knowledge gaps related to wood transport include transport distances of LW and thresholds for LW mobility in small to medium rivers. With respect to wood storage, we have limited data on longitudinal trends in LW loads within unaltered large and great rivers and on

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

An Analysis of the U.S. Wood Products Import Sector: Prospects for Tropical Wood Products Exporters

Directory of Open Access Journals (Sweden)

W.A.R.T.W. Bandara

2012-10-01

Full Text Available The U.S. has dramatically altered its wood product imports and exports during the past few years,and at present, it is the second largest wood product importer in the world. Hence, an understanding ofmarket structures, factors in selecting foreign suppliers, and the emphasis placed on environmentalissues/certification are critical to understand from the perspective of wood products importers in the U.S.This study provides an analysis of the U.S. wood products import sector with special emphasis on currentand future opportunities for tropical wood products exporters to the U.S. market.In this study, 158 wood products importers in the U.S. were surveyed using a mailingquestionnaire. The adjusted response rate was 40.6 percent. Results indicated that most of the respondentswere small to medium scale firms, but major importers of wood products. According to respondents,wood products to the U.S. mainly come from Brazil, Chile, and China. From the importers’ perspective,Brazilian wood products ranked first for its quality followed by wood products from Chile and Finland.Product quality, long term customer relationships, on-time delivery of orders, fair prices, and supplierreputation were the factors deemed important in selecting overseas suppliers. Majority of respondentswere importing certified wood products. FSC, SFI, and ISO 14000 were the mostly accepted certificationprograms. However, certification was not a major factor in foreign supplier selection criteria. Whenconsidered the U.S. wood products importers’ tendency to diversify their products and species imported,attractive opportunities exist for wood products suppliers from tropical countries.

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 ( ...

Wood preservation

Science.gov (United States)

Rebecca E. Ibach

1999-01-01

When left untreated in many outdoor applications, wood becomes subject to degradation by a variety of natural causes. Although some trees possess naturally occurring resistance to decay (Ch. 3, Decay Resistance), many are in short supply or are not grown in ready proximity to markets. Because most commonly used wood species, such as Southern Pine, ponderosa pine, and...

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...

Inside the guts of wood-eating catfishes: can they digest wood?

Science.gov (United States)

German, Donovan P

2009-11-01

To better understand the structure and function of the gastrointestinal (GI) tracts of wood-eating catfishes, the gross morphology, length, and microvilli surface area (MVSA) of the intestines of wild-caught Panaque nocturnus, P. cf. nigrolineatus "Marañon", and Hypostomus pyrineusi were measured, and contrasted against these same metrics of a closely related detritivore, Pterygoplichthys disjunctivus. All four species had anatomically unspecialized intestines with no kinks, valves, or ceca of any kind. The wood-eating catfishes had body size-corrected intestinal lengths that were 35% shorter than the detritivore. The MVSA of all four species decreased distally in the intestine, indicating that nutrient absorption preferentially takes place in the proximal and mid-intestine, consistent with digestive enzyme activity and luminal carbohydrate profiles for these same species. Wild-caught Pt. disjunctivus, and P. nigrolineatus obtained via the aquarium trade, poorly digested wood cellulose (<33% digestibility) in laboratory feeding trials, lost weight when consuming wood, and passed stained wood through their digestive tracts in less than 4 h. Furthermore, no selective retention of small particles was observed in either species in any region of the gut. Collectively, these results corroborate digestive enzyme activity profiles and gastrointestinal fermentation levels in the fishes' GI tracts, suggesting that the wood-eating catfishes are not true xylivores such as beavers and termites, but rather, are detritivores like so many other fishes from the family Loricariidae.

LCA-based optimization of wood utilization under special consideration of a cascading use of wood.

Science.gov (United States)

Höglmeier, Karin; Steubing, Bernhard; Weber-Blaschke, Gabriele; Richter, Klaus

2015-04-01

Cascading, the use of the same unit of a resource in multiple successional applications, is considered as a viable means to improve the efficiency of resource utilization and to decrease environmental impacts. Wood, as a regrowing but nevertheless limited and increasingly in demand resource, can be used in cascades, thereby increasing the potential efficiency per unit of wood. This study aims to assess the influence of cascading wood utilization on optimizing the overall environmental impact of wood utilization. By combining a material flow model of existing wood applications - both for materials provision and energy production - with an algebraic optimization tool, the effects of the use of wood in cascades can be modelled and quantified based on life cycle impact assessment results for all production processes. To identify the most efficient wood allocation, the effects of a potential substitution of non-wood products were taken into account in a part of the model runs. The considered environmental indicators were global warming potential, particulate matter formation, land occupation and an aggregated single score indicator. We found that optimizing either the overall global warming potential or the value of the single score indicator of the system leads to a simultaneous relative decrease of all other considered environmental impacts. The relative differences between the impacts of the model run with and without the possibility of a cascading use of wood were 7% for global warming potential and the single score indicator, despite cascading only influencing a small part of the overall system, namely wood panel production. Cascading led to savings of up to 14% of the annual primary wood supply of the study area. We conclude that cascading can improve the overall performance of a wood utilization system. Copyright © 2015 Elsevier Ltd. All rights reserved.

Creation of Wood Dust during Wood Processing: Size Analysis, Dust Separation, and Occupational Health

Directory of Open Access Journals (Sweden)

Eva Mračková

2015-11-01

Full Text Available Mechanical separators and fabric filters are being used to remove airborne fine particles generated during the processing and handling of wood. Such particles might have a harmful effect on employee health, not only in small- but also in large-scale wood processing facilities. The amount of wood dust and its dispersion conditions vary according to geometric boundary conditions. Thus, the dispersion conditions could be changed by changing the linear size of the particles. Moreover, the smaller the particles are, the more harmful they can be. It is necessary to become familiar with properties, from a health point of view, of wood dust generated from processing. Wood dust has to be sucked away from the processing area. The fractional separation efficiency of wood dust can be improved using exhaust and filtering devices. Filtration efficiency depends on moisture content, particle size, and device performance. Because of the carcinogenicity of wood dust, the concentration of wood dust in air has to be monitored regularly. Based on the results hereof, a conclusion can be made that both mechanical separators of types SEA and SEB as well as the fabric filters with FINET PES 1 textile are suitable for the separation of wet saw dust from all types of wooden waste produced within the process.

Reactivity and burnout of wood fuels

DEFF Research Database (Denmark)

Dall'Ora, Michelangelo

This thesis deals with the combustion of wood in pulverised fuel power plants. In this type of boiler, the slowest step in the wood conversion process is char combustion, which is one of the factors that not only determine the degree of fuel burnout, but also affect the heat release profile...... of different aspects relevant to wood combustion, including wood structure and composition, wood pyrolysis, wood char properties and wood char oxidation. The full scale campaign, which is the subject of Chapter 3, included sampling of wood fuel before and after milling and sampling of gas and particles...... at the top of the combustion chamber. The collected samples and data are used to obtain an evaluation of the mills in operation at the power plant, the particle size distribution of the wood fuel, as well as the char conversion attained in the furnace. In Chapter 4 an experimental investigation...

Application of molecular genetic methods for identification of wood-decaying fungi in wood constructions

OpenAIRE

Elena Bobeková; Michal Tomšovský; Petr Horáček

2008-01-01

The aim of the paper is to evaluate the utilization of molecular biology methods for detection of wood decaying fungi directly from decomposed wood using a commercial DNA extraction kit developed for soil substrates (PowerSoil™ DNA isolation kit). The experiment based on dry rot fungus (Serpula lacrymans) detection from inoculated wooden pieces under laboratory conditions was followed by field detection of wood-decaying fungi from wood structures on building constructions. Fungal DNA was ide...

Adhesive interactions with wood

Science.gov (United States)

Charles R. Frihart

2004-01-01

While the chemistry for the polymerization of wood adhesives has been studied systematically and extensively, the critical aspects of the interaction of adhesives with wood are less clearly understood. General theories of bond formation need to be modified to take into account the porosity of wood and the ability of chemicals to be absorbed into the cell wall....

Composite structure of wood cells in petrified wood

International Nuclear Information System (INIS)

Nowak, Jakub; Florek, Marek; Kwiatek, Wojciech; Lekki, Janusz; Chevallier, Pierre; Zieba, Emil; Mestres, Narcis; Dutkiewicz, E.M.; Kuczumow, Andrzej

2005-01-01

Special kinds of petrified wood of complex structure were investigated. All the samples were composed of at least two different inorganic substances. The original cell structure was preserved in each case. The remnants of the original biological material were detected in some locations, especially in the cell walls. The complex inorganic structure was superimposed on the remnant organic network. The first inorganic component was located in the lumena (l.) of the cells while another one in the walls (w.) of the cells. The investigated arrangements were as follows: calcite (l.)-goethite-hematite (w.)-wood from Dunarobba, Italy; pyrite (l.)-calcite (w.)-wood from Lukow, Poland; goethite (l.)-silica (w.)-wood from Kwaczala, Poland. The inorganic composition was analysed and spatially located by the use of three spectral methods: electron microprobe, X-ray synchrotron-based microprobe, μ-PIXE microprobe. The accurate mappings presenting 2D distribution of the chemical species were presented for each case. Trace elements were detected and correlated with the distribution of the main elements. In addition, the identification of phases was done by the use of μ-Raman and μ-XRD techniques for selected and representative points. The possible mechanisms of the described arrangements are considered. The potential synthesis of similar structures and their possible applications are suggested

Composite structure of wood cells in petrified wood

Energy Technology Data Exchange (ETDEWEB)

Nowak, Jakub [Department of Chemistry, Catholic University of Lublin, 20-718 Lublin (Poland); Florek, Marek [Department of Chemistry, Catholic University of Lublin, 20-718 Lublin (Poland); Kwiatek, Wojciech [Institute of Nuclear Physics, Department of Nuclear Spectroscopy, 31-342 Cracow (Poland); Lekki, Janusz [Institute of Nuclear Physics, Department of Nuclear Spectroscopy, 31-342 Cracow (Poland); Chevallier, Pierre [LPS, CEN Saclay et LURE, Universite Paris-Sud, Bat 209D, F-91405 Orsay (France); Zieba, Emil [Department of Chemistry, Catholic University of Lublin, 20-718 Lublin (Poland); Mestres, Narcis [Institut de Ciencia de Materials de Barcelona (ICMAB), Campus de la UAB, E-08193-Bellaterra (Spain); Dutkiewicz, E.M. [Institute of Nuclear Physics, Department of Nuclear Spectroscopy, 31-342 Cracow (Poland); Kuczumow, Andrzej [Department of Chemistry, Catholic University of Lublin, 20-718 Lublin (Poland)

2005-04-28

Special kinds of petrified wood of complex structure were investigated. All the samples were composed of at least two different inorganic substances. The original cell structure was preserved in each case. The remnants of the original biological material were detected in some locations, especially in the cell walls. The complex inorganic structure was superimposed on the remnant organic network. The first inorganic component was located in the lumena (l.) of the cells while another one in the walls (w.) of the cells. The investigated arrangements were as follows: calcite (l.)-goethite-hematite (w.)-wood from Dunarobba, Italy; pyrite (l.)-calcite (w.)-wood from Lukow, Poland; goethite (l.)-silica (w.)-wood from Kwaczala, Poland. The inorganic composition was analysed and spatially located by the use of three spectral methods: electron microprobe, X-ray synchrotron-based microprobe, {mu}-PIXE microprobe. The accurate mappings presenting 2D distribution of the chemical species were presented for each case. Trace elements were detected and correlated with the distribution of the main elements. In addition, the identification of phases was done by the use of {mu}-Raman and {mu}-XRD techniques for selected and representative points. The possible mechanisms of the described arrangements are considered. The potential synthesis of similar structures and their possible applications are suggested.

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.

Wood Volume Production and Use of 10 Woody Species in Semiarid Zones of Northeastern Mexico

Directory of Open Access Journals (Sweden)

Rahim Foroughbakhch

2012-01-01

Full Text Available A research strategy was established to analyze the structure of timber trees in terms of forest productivity (volume and wood density of 10 species. The native species Acacia farnesiana, Acacia schaffneri, Bumelia celastrina, Cercidium macrun, Condalia hookeri, Ebenopsis ebano, Helietta parvifolia, and Prosopis laevigata and the exotic species Eucalyptus camaldulensis and Leucaena leucocephala were chosen due to their ecological and economic importance to the rural villages of northeastern Mexico. Measurements of different growth parameters and volume of trees were evaluated. The introduced species E. camaldulensis and L. leucocephala showed the best performance in wood volume production per tree and per hectare when compared to the native species. Likewise, among the native species, E. ebano, P. laevigata, C. hookeri, and A. farnesiana tended to show better characteristics in terms of wood volume production in comparison to H. parvifolia, A. schaffneri, C. macrum, and B. celastrina. Results showed a high diversity on the properties studied. The high biomass produced by most of the species considered in this study revealed their great energetic potential when used as wood and firewood or vegetal charcoal.

Structure and function of wood

Science.gov (United States)

Alex Wiedenhoeft

2010-01-01

Wood is a complex biological structure, a composite of many chemistries and cell types acting together to serve the needs of a living plant. Attempting to understand wood in the context of wood technology, we have often overlooked the key and basic fact that wood evolved over the course of millions of years to serve three main functions in plants― conduction of water...

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

Acoustic and adsorption properties of submerged wood

Science.gov (United States)

Hilde, Calvin Patrick

Wood is a common material for the manufacture of many products. Submerged wood, in particular, is used in niche markets, such as the creation of musical instruments. An initial study performed on submerged wood from Ootsa Lake, British Columbia, provided results that showed that the wood was not suitable for musical instruments. This thesis re-examined the submerged wood samples. After allowing the wood to age unabated in a laboratory setting, the wood was retested under the hypothesis that the physical acoustic characteristics would improve. It was shown, however, that the acoustic properties became less adequate after being left to sit. The adsorption properties of the submerged wood were examined to show that the submerged wood had a larger accessible area of wood than that of control wood samples. This implied a lower amount of crystalline area within the submerged wood. From the combined adsorption and acoustic data for the submerged wood, relationships between the moisture content and speed of sound were created and combined with previous research to create a proposed model to describe how the speed of sound varies with temperature, moisture content and the moisture content corresponding to complete hydration of sorption sites within the wood.

Urban Wood Waste Resource Assessment; TOPICAL

International Nuclear Information System (INIS)

Wiltsee, G.

1998-01-01

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

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...

Survival, growth, wood basic density and wood biomass of seven ...

African Journals Online (AJOL)

A performance comparison of seven-year-old individuals of 13 Casuarina species/provenances in terms of survival, growth (diameter, height and volume), wood basic density and wood biomass was undertaken at Kongowe, Kibaha, Tanzania. The trial was laid out using a randomised complete block design with four ...

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...

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...

On-line automatic detection of wood pellets in pneumatically conveyed wood dust flow

Science.gov (United States)

Sun, Duo; Yan, Yong; Carter, Robert M.; Gao, Lingjun; Qian, Xiangchen; Lu, Gang

2014-04-01

This paper presents a piezoelectric transducer based system for on-line automatic detection of wood pellets in wood dust flow in pneumatic conveying pipelines. The piezoelectric transducer senses non-intrusively the collisions between wood pellets and the pipe wall. Wavelet-based denoising is adopted to eliminate environmental noise and recover the collision events. Then the wood pellets are identified by sliding a time window through the denoised signal with a suitable threshold. Experiments were carried out on a laboratory test rig and on an industrial pneumatic conveying pipeline to assess the effectiveness and operability of the system.

State-of-the-art of the European regulation on wood wastes and wood ashes valorization. Synthesis

International Nuclear Information System (INIS)

Mousseau, S.

2007-01-01

This study has the objective of comparing the regulations of 10 European countries with that of France, in relation to the classification and recycling of wood waste, in particular lightly treated wood, as well as recycling of wood ash. The first part relating to wood waste presents a detailed analysis by country as well as a summary, on the one hand, of the various sectors for recycling waste wood and, on the other, the emission limits for their energy recovery. Generally, there is a distinction between waste covered by the incineration directive, and the others, without any particular category for lightly treated wood. However, recommendations emerge from this that are based essentially on the regulations or guidelines observed in Germany, Austria and the United Kingdom. The second part relating to wood ash also a presents a detailed analysis by country as well as a summary of the various sectors of recycling and limit values for spreading. Ash is generally considered as waste, and is recycled on a case-by case basis. Only Germany and Austria have clearly integrated wood ash in their regulatory framework. Overall this study shows the need for uniform regulation at European level, establishing environment requirements for recycling wood waste and wood ash, in order to encourage development of the use of biomass

Wood Flour Moulding Technology: Implications for Technical ...

African Journals Online (AJOL)

The intent of this article is to demonstrate how wood waste called sawdust or wood flour can be transformed by plastic moulding machine into items of economic value. Wood flour is wood reduced to very fine particle form. It can be waste product from saw mills, wood working plants or produced from selected dry wood by ...

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)

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....

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.

Wood Modification at High Temperature and Pressurized Steam: a Relational Model of Mechanical Properties Based on a Neural Network

Directory of Open Access Journals (Sweden)

Hong Yang

2015-07-01

Full Text Available Thermally modified wood has high dimensional stability and biological durability.But if the process parameters of thermal modification are not appropriate, then there will be a decline in the physical properties of wood.A neural network algorithm was employed in this study to establish the relationship between the process parameters of high-temperature and high-pressure thermal modification and the mechanical properties of the wood. Three important parameters: temperature, relative humidity, and treatment time, were considered as the inputs to the neural network. Back propagation (BP neural network and radial basis function (RBF neural network models for prediction were built and compared. The comparison showed that the RBF neural network model had advantages in network structure, convergence speed, and generalization capacity. On this basis, the inverse model, reflecting the relationship between the process parameters and the mechanical properties of wood, was established. Given the desired mechanical properties of the wood, the thermal modification process parameters could be inversely optimized and predicted. The results indicated that the model has good learning ability and generalization capacity. This is of great importance for the theoretical and applicational studies of the thermal modification of wood.

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...

Power generation from waste wood

Energy Technology Data Exchange (ETDEWEB)

Nitsche, H

1980-04-18

Since the energy crisis, power generation from waste wood has become increasingly important. The most profitable way to use waste wood in woodworking plants with an annual production of 100 to 150,000 m/sup 3/ solid measure of wood chips and bark is by combustion and thermal energy recovery. In plants with an annual production of 10,000 m/sup 3/ solid measure of wood chips and bark, electric power generation is a suitable application.

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

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.

Bacterial Community Succession in Pine-Wood Decomposition.

Science.gov (United States)

Kielak, Anna M; Scheublin, Tanja R; Mendes, Lucas W; van Veen, Johannes A; Kuramae, Eiko E

2016-01-01

Though bacteria and fungi are common inhabitants of decaying wood, little is known about the relationship between bacterial and fungal community dynamics during natural wood decay. Based on previous studies involving inoculated wood blocks, strong fungal selection on bacteria abundance and community composition was expected to occur during natural wood decay. Here, we focused on bacterial and fungal community compositions in pine wood samples collected from dead trees in different stages of decomposition. We showed that bacterial communities undergo less drastic changes than fungal communities during wood decay. Furthermore, we found that bacterial community assembly was a stochastic process at initial stage of wood decay and became more deterministic in later stages, likely due to environmental factors. Moreover, composition of bacterial communities did not respond to the changes in the major fungal species present in the wood but rather to the stage of decay reflected by the wood density. We concluded that the shifts in the bacterial communities were a result of the changes in wood properties during decomposition and largely independent of the composition of the wood-decaying fungal communities.

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.

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...

The influence of irradiated wood filler on some properties of polypropylene - wood composites

Directory of Open Access Journals (Sweden)

Điporović-Momčilović Milanka

2007-01-01

Full Text Available The problem of compatibility between the wood filler and thermoplastic matrix is of essential importance in composite production. Numerous methods have been developed for increasing this compatibility, which is still representing a challenging objective of composite research throughout the world. The research into these methods is primarily directed towards their efficiency from the viewpoint of the composite performance and their economical acceptability. The latter is of particular importance for the composite production in the developing countries with respect to the shortage of the corresponding funds. With this respect, the utilization of ionizing radiation might have considerable advantages. In this research, the beech wood flour was irradiated by a dose of 10 kGy of 60Co gamma rays for purpose of provoking the changes by the ionizing effect. The effects of ionizing radiation upon the properties of wood particles have been examined by IR spectroscopy and by determination of contents of hydroxyl groups in wood by acetylating as an indirect method. All these methods have been expected to reveal the chemical effects of the applied radiation treatment. The irradiated and the control wood flour were used in order to produce the samples of composite with polypropylene. The polypropylene-wood flour (PP-WF composites were produced with 40% of wood particles having fraction size 0.3 mm. The melt-blended composites were modified with amido-acrylic acid (AMACA as a new coupling agent synthesized for this propose in amount of 6 wt.% (based on wood filler and successively with 0.05 wt.% (based on PP of organic peroxide during mixing step. The composites containing coupling agents showed superior mechanical properties, compared to the untreated one. The highest extent of improvement of tensile was achieved in PP-WFl composites modified with AMACA coupling agent.

Methane from wood

Energy Technology Data Exchange (ETDEWEB)

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

2005-07-15

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)

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)

Temperature effects on wood anatomy, wood density, photosynthesis and biomass partitioning of Eucalyptus grandis seedlings.

Science.gov (United States)

Thomas, D S; Montagu, K D; Conroy, J P

2007-02-01

Wood density, a gross measure of wood mass relative to wood volume, is important in our understanding of stem volume growth, carbon sequestration and leaf water supply. Disproportionate changes in the ratio of wood mass to volume may occur at the level of the whole stem or the individual cell. In general, there is a positive relationship between temperature and wood density of eucalypts, although this relationship has broken down in recent years with wood density decreasing as global temperatures have risen. To determine the anatomical causes of the effects of temperature on wood density, Eucalyptus grandis W. Hill ex Maiden seedlings were grown in controlled-environment cabinets at constant temperatures from 10 to 35 degrees C. The 20% increase in wood density of E. grandis seedlings grown at the higher temperatures was variously related to a 40% reduction in lumen area of xylem vessels, a 10% reduction in the lumen area of fiber cells and a 10% increase in fiber cell wall thickness. The changes in cell wall characteristics could be considered analogous to changes in carbon supply. Lumen area of fiber cells declined because of reduced fiber cell expansion and increased fiber cell wall thickening. Fiber cell wall thickness was positively related to canopy CO2 assimilation rate (Ac), which increased 26-fold because of a 24-fold increase in leaf area and a doubling in leaf CO2 assimilation rate from minima at 10 and 35 degrees C to maxima at 25 and 30 degrees C. Increased Ac increased seedling volume, biomass and wood density; but increased wood density was also related to a shift in partitioning of seedling biomass from roots to stems as temperature increased.

Landscape factors and hydrology influence mercury concentrations in wading birds breeding in the Florida Everglades, USA.

Science.gov (United States)

Herring, Garth; Eagles-Smith, Collin A; Ackerman, Joshua T; Gawlik, Dale E; Beerens, James M

2013-08-01

The hydrology of wetland ecosystems is a key driver of both mercury (Hg) methylation and waterbird foraging ecology, and hence may play a fundamental role in waterbird exposure and risk to Hg contamination. However, few studies have investigated hydrological factors that influence waterbird Hg exposure. We examined how several landscape-level hydrological variables influenced Hg concentrations in great egret and white ibis adults and chicks in the Florida Everglades. The great egret is a visual "exploiter" species that tolerates lower prey densities and is less sensitive to hydrological conditions than is the white ibis, which is a tactile "searcher" species that pursues higher prey densities in shallow water. Mercury concentrations in adult great egrets were most influenced by the spatial region that they occupied in the Everglades (higher in the southern region); whereas the number of days a site was dry during the previous dry season was the most important factor influencing Hg concentrations in adult ibis (Hg concentrations increased with the number of days dry). In contrast, Hg concentrations in egret chicks were most influenced by calendar date (increasing with date), whereas Hg concentrations in ibis chicks were most influenced by chick age, region, and water recession rate (Hg concentrations decreased with age, were higher in the southern regions, and increased with positive water recession rates). Our results indicate that both recent (preceding two weeks) hydrological conditions, and those of the prior year, influence Hg concentrations in wading birds. Further, these results suggest that Hg exposure in wading birds is driven by complex relationships between wading bird behavior and life stage, landscape hydrologic patterns, and biogeochemical processes. Published by Elsevier B.V.

Cadmium and lead in tissues of Mallards (Anas platyrhynchos) and Wood Ducks (Aix sponsa) using the Illinois River (USA)

International Nuclear Information System (INIS)

Levengood, J.M.

2003-01-01

Tissue lead and cadmium concentrations were examined in two common, widely distributed species of duck, utilizing a major river system. - Cadmium and lead concentrations were determined in the tissues of Mallards and Wood Ducks collected from two waterfowl management areas along the Illinois River, USA, during the autumn and late winter of 1997-1998. Lead concentrations in livers of Mallards were lower than previously reported, and, along with those in a small sample of Wood Duck livers, were within background levels (<2.0 μg/g wet weight). Mean concentrations of cadmium in the kidneys of Wood Ducks utilizing the Illinois River were four times greater than in after-hatch-year Mallards, and 14 times greater than in hatch-year Mallards. Concentrations of cadmium in the kidneys of Wood Ducks were comparable with those of specimens dosed with cadmium or inhabiting contaminated areas in previous studies. Wood Ducks utilizing wetlands associated with the Illinois River, and presumably other portions of the lower Great Lakes region, may be chronically exposed to cadmium

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...

Wood as a home heating fuel

International Nuclear Information System (INIS)

Wood, K.

1991-01-01

This article describes the development of clean-burning technology in three types of wood-burning appliances: catalytic, non-catalytic, and pellet stoves. A recent study by the Washington State Energy Extension Office concluded that in homes that use both electricity and wood, 73 megawatts of electricity/yr were saved by using wood. Since wood-burning stoves can now meet air quality standards, wood could be considered to be a greenhouse-neutral fuel if more trees are planted as they are consumed

Microbial Communities in Sunken Wood Are Structured by Wood-Boring Bivalves and Location in a Submarine Canyon

Science.gov (United States)

Fagervold, Sonja K.; Romano, Chiara; Kalenitchenko, Dimitri; Borowski, Christian; Nunes-Jorge, Amandine; Martin, Daniel; Galand, Pierre E.

2014-01-01

The cornerstones of sunken wood ecosystems are microorganisms involved in cellulose degradation. These can either be free-living microorganisms in the wood matrix or symbiotic bacteria associated with wood-boring bivalves such as emblematic species of Xylophaga, the most common deep-sea woodborer. Here we use experimentally submerged pine wood, placed in and outside the Mediterranean submarine Blanes Canyon, to compare the microbial communities on the wood, in fecal pellets of Xylophaga spp. and associated with the gills of these animals. Analyses based on tag pyrosequencing of the 16S rRNA bacterial gene showed that sunken wood contained three distinct microbial communities. Wood and pellet communities were different from each other suggesting that Xylophaga spp. create new microbial niches by excreting fecal pellets into their burrows. In turn, gills of Xylophaga spp. contain potential bacterial symbionts, as illustrated by the presence of sequences closely related to symbiotic bacteria found in other wood eating marine invertebrates. Finally, we found that sunken wood communities inside the canyon were different and more diverse than the ones outside the canyon. This finding extends to the microbial world the view that submarine canyons are sites of diverse marine life. PMID:24805961

Application of molecular genetic methods for identification of wood-decaying fungi in wood constructions

Directory of Open Access Journals (Sweden)

Elena Bobeková

2008-01-01

Full Text Available The aim of the paper is to evaluate the utilization of molecular biology methods for detection of wood decaying fungi directly from decomposed wood using a commercial DNA extraction kit developed for soil substrates (PowerSoil™ DNA isolation kit. The experiment based on dry rot fungus (Serpula lacrymans detection from inoculated wooden pieces under laboratory conditions was followed by field detection of wood-decaying fungi from wood structures on building constructions. Fungal DNA was identified using the PCR–based methods including species-specific PCR and sequencing of amplified ITS region of ribosomal DNA.

Fast enhancement on hydrophobicity of poplar wood surface using low-pressure dielectric barrier discharges (DBD) plasma

Science.gov (United States)

Chen, Weimin; Zhou, Xiaoyan; Zhang, Xiaotao; Bian, Jie; Shi, Shukai; Nguyen, Thiphuong; Chen, Minzhi; Wan, Jinglin

2017-06-01

The hydrophilicity of woody products leads to deformation and cracks, which greatly limits its applications. Low-pressure dielectric barrier discharge (DBD) plasma using hexamethyldisiloxane was applied in poplar wood surface to enhance the hydrophobicity. The chemical properties, micro-morphology, and contact angles of poplar wood surface before and after plasma treatment were investigated by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), x-ray photoelectron spectroscopy (XPS), scanning electron microscope and energy dispersive analysis of X-ray (SEM-EDX), atomic force microscopy (AFM), and optical contact angle measurement (OCA). Moreover, tinfoil film was used as the base to reveal the enhancement mechanism. The results showed that hexamethyldisiloxane monomer is first broken into several fragments with active sites and hydrophobic chemical groups. Meanwhile, plasma treatment results in the formation of free radicals and active sites in the poplar wood surface. Then, the fragments are reacted with free radicals and incorporated into the active sites to form a network structure based on the linkages of Si-O-Si and Sisbnd Osbnd C. Plasma treatment also leads to the formation of acicular nano-structure in poplar wood surface. These facts synergistically enhance the hydrophobicity of poplar wood surface, demonstrating the dramatically increase in the equilibrium contact angle by 330%.

Wood plastic combination

International Nuclear Information System (INIS)

Cunanan, S.A.; Bonoan, L.S.; Verceluz, F.P.; Azucena, E.A.

1976-03-01

The purpose of this study is to improve the physical and mechaniproperties of local inferior quality wood species by radiation-induced graft polymerization with plastic monomers. The process involves the following: 1) Preparation of sample; 2) Impregnation of sample with the monomers; 3) Irradiation of the impregnated sample with the use of 20,000 curie Co-60 as gamma-source; 4) Drying of irradiated sample to remove the unpolymerized monomer. Experimentation on different wood species were undertaken and the results given. From the results obtained, it can be concluded that the monomers systems MMA, MMA-USP, and styrene-USP are suitable for graft polymerization with the wood species almon, apitong, bagtikan, mayapis, red lauan, and tanguile. This is shown by their maximum conversion value which range from 86% to 96% with the optimum dose range of 1 to 2 Mrads. However, in the application of WPC process, properties that are required in a given wood product must be considered, thus aid in the selection of the monomer system to be used with a particular wood species. Some promising applications of WPC is in the manufacture of picker sticks, shuttles, and bobbins for the textile industry. However, there is a need for a pilot plant scale study so that an economic assessment of the commercial feasibility of this process can be made

FLEXURAL TESTING OF WOOD-CONCRETE COMPOSITE BEAM MADE FROM KAMPER AND BANGKIRAI WOOD

Directory of Open Access Journals (Sweden)

Fengky Satria Yoresta

2015-07-01

Full Text Available Certain wood has a tensile strength that almost equal with steel rebar in reinforced concrete beams. This research aims to understand the capacity and flexural behavior of concrete beams reinforced by wood (wood-concrete composite beam. Two different types of beams based on placement positions of wood layers are proposed in this study. Two kinds of wood used are consisted of Bangkirai (Shorea laevifolia and Kamper (Cinnamomum camphora, meanwhile the concrete mix ratio for all beams is 1 cement : 2 fine aggregates : 3 coarse aggregates. Bending test is conducted by using one-point loading method. The results show that composite beam using Bangkirai wood is stronger than beams using Kamper wood. More thicker wood layer in tensile area will increase the flexural strength of beams. Crack patterns identified could be classified into flexural cracks, shear cracks, and split on wood layer   Beberapa jenis kayu tertentu memiliki kekuatan tarik yang hampir sama dengan tulangan baja pada balok beton bertulang. Penelitian ini bertujuan memahami kapasitas dan perilaku lentur balok beton bertulang yang diperkuat menggunakan kayu (balok komposit beton-kayu. Dua tipe balok yang berbeda berdasarkan posisi penempatan kayu digunakan dalam penelitian ini. Dua jenis kayu yang digunakan adalah kayu Bangkirai (Shorea laevifolia and Kamper (Cinnamomum camphora, sementara itu rasio campuran beton untuk semua balok menggunakan perbandingan 1 semen : 2 agregat halus : 3 agregat kasar. Pengujian lentur dilakukan menggunakan metode one-point loading. Hasil penelitian menunjukkan bahwa balok komposit dengan kayu Bangkirai lebih kuat dibandingkan balok dengan kayu Kamper. Semakin tebal lapisan kayu yang berada di daerah tarik akan meningkatkan kekuatan lentur balok. Pola kerusakan yang teridentifikasi dapat diklasifikasikan menjadi retak lentur, retak geser, dan pecah pada kayu REFERENCES Boen T. (2010. Retrofitting Simple Buildings Damaged by Earthquakes. World Seismic

The case for wood-fuelled heating

International Nuclear Information System (INIS)

Bent, Ewan

2001-01-01

This article looks at the wood heating industry in the UK and examines the heat market and the growth potential in the domestic, public, agricultural and commercial sectors. The current status of wood-fueled heating technology is considered, along with log and chip boilers, and the use of pellet fuel. The economics of wood-fuelled heating, the higher level of utilisation of wood-fuelled heating by utilities in northern European countries compared with the UK, and the barriers to the exploitation of wood fuelled heating are examined

Bacterial community succession in pine-wood decomposition

Directory of Open Access Journals (Sweden)

Anna eKielak

2016-03-01

Full Text Available Though bacteria and fungi are common inhabitants of decaying wood, little is known about the relationship between bacterial and fungal community dynamics during natural wood decay. Based on previous studies involving inoculated wood blocks, strong fungal selection on bacteria abundance and community composition was expected to occur during natural wood decay. Here we focused on bacterial and fungal community compositions in pine wood samples collected from dead trees in different stages of decomposition. We showed that bacterial communities undergo less drastic changes than fungal communities during wood decay. Furthermore, we found that bacterial community assembly was a stochastic process at initial stage of wood decay and became more deterministic in later stages, likely due to environmental factors. Moreover, composition of bacterial communities did not respond to the changes in the major fungal species present in the wood but rather to the stage of decay reflected by the wood density. We concluded that the shifts in the bacterial communities were a result of the changes in wood properties during decomposition and largely independent of the composition of the wood-decaying fungal communities.

Macrophotographic wood atlas of Annonaceae.

NARCIS (Netherlands)

Koek-Noorman, J.; Westra, L.I.T.

2012-01-01

In this article, a general description of the microscopic wood anatomy of Annonaceae is given. We provide a description of the wood anatomical features of the family and of all subfamilies and tribes, all from material in the Utrecht Wood collection. Hand-lens images can be an important help in

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...

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…

Physical and mechanical properties of bio-composites from wood particles and liquefied wood resin

Science.gov (United States)

Hui Pan; Todd F. Shupe; Chung-Yun Hse

2009-01-01

Compression molded composites were made from wood particles and a liquefied wood/phenol/formaldehyde co-condensed resin. Based on our previous research, a phenol to wood (P/W) ratio of 2/1 was chosen for this study. The two experimental variables selected were: 1) liquefaction temperature (150o and 180oC) and 2) cooking method (atmospheric and sealed). Panels were...

The wood energy in France

International Nuclear Information System (INIS)

Douard, F.; Oremus, Y.; Garsault-Fabbi, A.

2007-01-01

The program law fixing the energy policy (POPE Law of the 13 july 2005) fixes an objective of 50% of growth for the renewable heat. As this renewable heat is today generated by the biomass, it seems necessary to adjust all the efforts on this sector. This document proposes to takes stock on the wood energy in France. It presents the wood fuels, an evaluation of the Wood-Energy Plan decided by the ADEME in 2000, the wood heat networks, and some example of installations. (A.L.B.)

2000-2006 National Wood Energy Programme. 2000-2005 Activities Report

International Nuclear Information System (INIS)

2006-01-01

2005 was marked by key decisions which were taken with the aim of developing the biomass sector as a substitute for fossil fuels. Indeed, to achieve the ambitious objectives for renewable sources of energy set out by the July 2005 Energy Policy Orientation Programme (POPE), we must make great use of biomass, particularly to increase by 50% the share of renewable thermal energy between now and 2010 and to enable biofuels to represent 7% of all fuels used at the same date. To a lesser extent, and in conjunction with heat production, the share of biomass in renewable electricity production also needs to rise. Both the resource and key supply players are there and are ready to get organised in order to rise to these challenges. There is an abundant supply of agricultural and forest by-products. More than sixty companies organise and deliver heating wood. More than 300 government and professional promotion, regulatory, PR, finance, equipment construction and operation, research and engineering organizations are involved in this market. The strategic and economic context is highly favourable in the light of laws, directives and international agreements aiming to combat greenhouse gas emissions, but also due to the structural pressure on the price of fossil fuels. Wood energy, as a renewable energy source, has an important role to play in this context of growth. Furthermore, the wood energy sector should be developed using an exemplary sustainable development approach, which means that all the economic, social and environmental effects are taken into account. In order to comprehensively assess the sector's environmental impact, a full chapter of this report presents the work and programmes set up by ADEME to reduce pollutant emissions produced by biomass combustion, particularly from private households. Moreover, consultation and dialogue between those involved must be widened in order to enable all wood users to benefit from 'best forest use' which will be a key

An assessment of management practices of wood and wood-related wastes in the urban environment

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-02-01

The US Environmental Protection Agency estimates that yard waste{sup 1} accounts for approximately 16% of the municipal solid waste (MSW) stream (US EPA, 1994). Until recently, specific data and related information on this component of the (MSW) stream has been limited. The purposes of this study, phase two of the three-phase assessment of urban wood waste issues, are to assess and describe current alternatives to landfills for urban wood waste management; provide guidance on the management of urban wood waste to organizations that produce or manage wood waste; and clarify state regulatory and policy positions affecting these organizations. For this study, urban wood waste is defined as solid waste generated by tree and landscape maintenance services (public and private). Urban wood waste includes the following materials: unchipped mixed wood, unchipped logs, and unchipped tops and brush; clearing and grubbing waste; fall leaves and grass clippings; and chips and whole stumps. Construction and demolition debris and consumer-generated yard waste are not included in this study. Generators of urban wood waste include various organizations; municipal, county, and commercial tree care divisions; nurseries, orchards, and golf courses; municipal park and recreation departments; and electric and telephone utility power line maintenance, excavator and land clearance, and landscape organizations. (1) US EPA defines yard waste as ''yard trimmings'' which includes ''grass, leaves and tree brush trimmings from residential, institutional, and commercial sources.''

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....

Technologies for small scale wood-fueled combined heat and power systems

Energy Technology Data Exchange (ETDEWEB)

Houmann Jakobsen, H.; Houmoeller, S.; Thaaning Pedersen, L.

1998-01-01

The aim of this study is to describe and compare different technologies for small cogeneration systems (up to 2-3 MW{sub e}), based on wood as fuel. For decentralized cogeneration, i.e. for recovering energy from saw mill wood wastes or heat supply for small villages, it is vital to know the advantages and disadvantages of the different technologies. Also, for the decision-makers it is of importance to know the price levels of the different technologies. A typical obstacle for small wood cogeneration systems is the installation costs. The specific price (per kW) is usually higher than for larger plants or plants using fossil fuels. For a saw mill choosing between cogeneration and simple heat production, however, the larger installation costs are counter weighed by the sale of electricity, while the fuel consumption is the same. Whether it is profitable or not to invest in cogeneration is often hard to decide. For many years small wood cogeneration systems have been too expensive, leading to the construction of only heat producing systems due to too high price levels of small steam turbines. In recent years a great deal of effort has been put into research and developing of new technologies to replace this traditional steam turbine. Among these are: Steam engines; Stirling engines; Indirectly fired gas turbines; Pressurized down draft combustion. Along with the small scale traditional steam turbines, these technologies will be evaluated in this study. When some or all these technologies are fully developed and commercial, a strong means of reducing the strain on the environment and the greenhouse effect will be available, as the total efficiency is high (up to 90%) and wood is an energy source in balance with nature. (au) EFP-95. 19 refs.

Tracing nitrogen accumulation in decaying wood and examining its impact on wood decomposition rate

Science.gov (United States)

Rinne, Katja T.; Rajala, Tiina; Peltoniemi, Krista; Chen, Janet; Smolander, Aino; Mäkipää, Raisa

2016-04-01

Decomposition of dead wood, which is controlled primarily by fungi is important for ecosystem carbon cycle and has potentially a significant role in nitrogen fixation via diazotrophs. Nitrogen content has been found to increase with advancing wood decay in several studies; however, the importance of this increase to decay rate and the sources of external nitrogen remain unclear. Improved knowledge of the temporal dynamics of wood decomposition rate and nitrogen accumulation in wood as well as the drivers of the two processes would be important for carbon and nitrogen models dealing with ecosystem responses to climate change. To tackle these questions we applied several analytical methods on Norway spruce logs from Lapinjärvi, Finland. We incubated wood samples (density classes from I to V, n=49) in different temperatures (from 8.5oC to 41oC, n=7). After a common seven day pre-incubation period at 14.5oC, the bottles were incubated six days in their designated temperature prior to CO2 flux measurements with GC to determine the decomposition rate. N2 fixation was measured with acetylene reduction assay after further 48 hour incubation. In addition, fungal DNA, (MiSeq Illumina) δ15N and N% composition of wood for samples incubated at 14.5oC were determined. Radiocarbon method was applied to obtain age distribution for the density classes. The asymbiotic N2 fixation rate was clearly dependent on the stage of wood decay and increased from stage I to stage IV but was substantially reduced in stage V. CO2 production was highest in the intermediate decay stage (classes II-IV). Both N2 fixation and CO2 production were highly temperature sensitive having optima in temperature 25oC and 31oC, respectively. We calculated the variation of annual levels of respiration and N2 fixation per hectare for the study site, and used the latter data together with the 14C results to determine the amount of N2 accumulated in wood in time. The proportion of total nitrogen in wood

How to make a beetle out of wood: multi-elemental stoichiometry of wood decay, xylophagy and fungivory.

Science.gov (United States)

Filipiak, Michał; Weiner, January

2014-01-01

The majority of terrestrial biomass is wood, but the elemental composition of its potential consumers, xylophages, differs hugely from that of wood. This causes a severe nutritional imbalance. We studied the stoichiometric relationships of 11 elements (C, N, P, K, Ca, Mg, Fe, Zn, Mn, Cu, Na) in three species of pine-xylem-feeding insects, Stictoleptura rubra, Arhopalus rusticus (Coleoptera, Cerambycidae) and Chalcophora mariana (Coleoptera, Buprestidae), to elucidate their mechanisms of tissue growth and to match their life histories to their dietary constraints. These beetles do not differ from other Coleoptera in their absolute elemental compositions, which are approximately 1000 (N), 100 (P, Cu) and 50 (K, Na) times higher than in dead but undecayed pine wood. This discrepancy diminishes along the wood decay gradient, but the elemental concentrations remain higher by an order of magnitude in beetles than in highly decayed wood. Numerical simulation of the life history of S. rubra shows that feeding on nutrient-poor undecayed wood would extend its development time to implausible values, whereas feeding on highly decomposed wood (heavily infected with fungi) would barely balance its nutritional budget during the long development period of this species. The changes in stoichiometry indicate that the relative change in the nutrient levels in decaying wood cannot be attributed solely to carbon loss resulting from decomposer respiration: the action of fungi substantially enriches the decaying wood with nutritional elements imported from the outside of the system, making it a suitable food for wood-eating invertebrates.

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.

Wood Specific Gravity Variations and Biomass of Central African Tree Species: The Simple Choice of the Outer Wood.

Directory of Open Access Journals (Sweden)

Jean-François Bastin

Full Text Available Wood specific gravity is a key element in tropical forest ecology. It integrates many aspects of tree mechanical properties and functioning and is an important predictor of tree biomass. Wood specific gravity varies widely among and within species and also within individual trees. Notably, contrasted patterns of radial variation of wood specific gravity have been demonstrated and related to regeneration guilds (light demanding vs. shade-bearing. However, although being repeatedly invoked as a potential source of error when estimating the biomass of trees, both intraspecific and radial variations remain little studied. In this study we characterized detailed pith-to-bark wood specific gravity profiles among contrasted species prominently contributing to the biomass of the forest, i.e., the dominant species, and we quantified the consequences of such variations on the biomass.Radial profiles of wood density at 8% moisture content were compiled for 14 dominant species in the Democratic Republic of Congo, adapting a unique 3D X-ray scanning technique at very high spatial resolution on core samples. Mean wood density estimates were validated by water displacement measurements. Wood density profiles were converted to wood specific gravity and linear mixed models were used to decompose the radial variance. Potential errors in biomass estimation were assessed by comparing the biomass estimated from the wood specific gravity measured from pith-to-bark profiles, from global repositories, and from partial information (outer wood or inner wood.Wood specific gravity profiles from pith-to-bark presented positive, neutral and negative trends. Positive trends mainly characterized light-demanding species, increasing up to 1.8 g.cm-3 per meter for Piptadeniastrum africanum, and negative trends characterized shade-bearing species, decreasing up to 1 g.cm-3 per meter for Strombosia pustulata. The linear mixed model showed the greater part of wood specific gravity

Wood Specific Gravity Variations and Biomass of Central African Tree Species: The Simple Choice of the Outer Wood.

Science.gov (United States)

Bastin, Jean-François; Fayolle, Adeline; Tarelkin, Yegor; Van den Bulcke, Jan; de Haulleville, Thales; Mortier, Frederic; Beeckman, Hans; Van Acker, Joris; Serckx, Adeline; Bogaert, Jan; De Cannière, Charles

2015-01-01

Wood specific gravity is a key element in tropical forest ecology. It integrates many aspects of tree mechanical properties and functioning and is an important predictor of tree biomass. Wood specific gravity varies widely among and within species and also within individual trees. Notably, contrasted patterns of radial variation of wood specific gravity have been demonstrated and related to regeneration guilds (light demanding vs. shade-bearing). However, although being repeatedly invoked as a potential source of error when estimating the biomass of trees, both intraspecific and radial variations remain little studied. In this study we characterized detailed pith-to-bark wood specific gravity profiles among contrasted species prominently contributing to the biomass of the forest, i.e., the dominant species, and we quantified the consequences of such variations on the biomass. Radial profiles of wood density at 8% moisture content were compiled for 14 dominant species in the Democratic Republic of Congo, adapting a unique 3D X-ray scanning technique at very high spatial resolution on core samples. Mean wood density estimates were validated by water displacement measurements. Wood density profiles were converted to wood specific gravity and linear mixed models were used to decompose the radial variance. Potential errors in biomass estimation were assessed by comparing the biomass estimated from the wood specific gravity measured from pith-to-bark profiles, from global repositories, and from partial information (outer wood or inner wood). Wood specific gravity profiles from pith-to-bark presented positive, neutral and negative trends. Positive trends mainly characterized light-demanding species, increasing up to 1.8 g.cm-3 per meter for Piptadeniastrum africanum, and negative trends characterized shade-bearing species, decreasing up to 1 g.cm-3 per meter for Strombosia pustulata. The linear mixed model showed the greater part of wood specific gravity variance was

Roof modular system in wood and particle board (OSB to rural construction

Directory of Open Access Journals (Sweden)

Juliano Fiorelli

2012-06-01

Full Text Available Wood is a material of great applicability in construction, with advantageous properties to form various structural systems, such as walls and roof. Most of the roof structural systems follow models that have remained unchanged for a long time. A roof modular system in distinguished materials is proposed: reforested wood (Pine, oriented strand board (OSB and roof tiles made of recycled long-life packaging material in order to be applied in rural construction. In this alternative, besides the benefit of giving destination packages with long-life thermal comfort, it also highlights the use of reforestated wood being the cultivation of such species that provides incentive for agribusiness. The structural performance of this alternative was evaluated through computer modeling and test results of two modular panels. The analysis is based on the results of vertical displacements, deformations and stresses. A positive correlation between theoretical and experimental values was observed, indicating the model's feasibility for use in roof structures. Therefore, the modular system represents a solution to new architecture conceptions to rural construction, for example, storage construction, cattle handling and poultry, with benefits provided by prefabricated building systems.

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)

Wood pellets in a power plant - mixed combustion of coal and wood pellets

International Nuclear Information System (INIS)

Nupponen, M.

2001-01-01

The author reviews in his presentation the development of Turku Energia, the organization of the company, the key figures of the company in 2000, as well as the purchase of energy in 2000. He also presents the purchase of basic heat load, the energy production plants of the company, the sales of heat in 2000, the emissions of the plants, and the fuel consumption of the plants in 2000. The operating experiences of the plants are also presented. The experiences gained in Turku Energia on mixed combustion of coal and wood pellets show that the mixing ratios, used at the plants, have no effect on the burning properties of the boiler, and the use of wood pellets with coal reduce the SO 2 and NO x emissions slightly. Simultaneously the CO 2 share of the wood pellets is removed from the emissions calculations. Several positive effects were observed, including the disappearance of the coal smell of the bunker, positive publicity of the utilization of wood pellets, and the subsidies for utilization of indigenous fuels in power generation. The problems seen include the tendency of wood pellets to arc the silos, especially when the pellets include high quantities of dust, and the loading of the trucks and the pneumatic unloading of the trucks break the pellets. Additionally the wood pellets bounce on the conveyor so they drop easily from the conveyor, the screw conveyors designed for conveying grain are too weak and they get stuck easily, and static electricity is easily generated in the plastic pipe used as the discharge pipe for wood pellet (sparkling tendency). This disadvantage has been overcome by using metal net and grounding

Continued growth expected for wood energy despite turbulence of the economic crisis : wood energy markets, 2008-2009

Science.gov (United States)

Rens Hartkamp; Bengt Hillring; Warren Mabee; Olle Olsson; Kenneth Skog; Henry Spelter; Johan Vinterback; Antje Wahl

2009-01-01

The economic crisis has not reduced the demand for wood energy, which is expected to continue to grow. The downturn in sawmill production caused a shortage of raw material supply for wood pellet producers. With decreased demand for pulpwood-quality roundwood for wood and paper products in 2009, some pulpwood is being converted into wood energy. Economies of scale are...

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 ...

Robert Wood Johnson Foundation

Science.gov (United States)

Robert Wood Johnson Foundation Search How We Work Our Focus Areas About RWJF Search Menu How We Work Grants ... Learn more For Grantees and Grantseekers The Robert Wood Johnson Foundation funds a wide array of programs ...

Advantages of the use of energy wood

International Nuclear Information System (INIS)

Kaerhae, K.; Aarnio, J.; Maekinen, P.

2000-01-01

According to the Regional Forestry Associations it would be possible to develop the harvesting of energy wood by increasing the use of it. The study was made at the areas of 34 regional forestry associations as an inquiry to the executive managers, as well as the persons responsible for timber trade, harvesting or regional affairs. The inquiries studied the use of energy wood and the user of them at the areas of the associations, as well as the amounts of harvesting and the realization of it. Only a third of the associations have large energy wood consuming plants (using more than 500 m 3 energy wood per year). The closest large energy wood consuming plant was in the average 31 km from the office of the association. The average energy wood use of the plant was 20 000 m 3 /a, the variation being 700 - 200 000 m 3 /a. The energy wood purchase range of the plants varied from few kilometers to hundred kilometers, the average being 47 km. Most of the energy wood was harvested from forest regeneration areas. Some of the energy wood is also harvested from young forest maintenance and thinning areas. The estimated harvesting of energy wood in 1999 was 6300 m 3 . A part of the energy wood is used for heating the farms and other small real estates, and a part is used for heating larger buildings like schools, hospitals, factories. The fees to the associations for purchase of energy wood varied significantly. The range was 2.00 - 11.00 FIM/m 3 . One association charged 300 FIM/parcel, and in one association the price depend on the amount of wood acquired from the lot, the unit price being 0.5 FIM/m 3 . It appeared that the associations estimated the use of energy wood to increase. The level in 1999 was 6300 m 3 and it is estimated to increase to 14 300 m 3 in 2005. The associations estimated that the levels can only be achieved if the stumpage price of energy wood may not be 0.0 FIM. Even a marginal price would lead to an increased harvesting of energy wood. The associations

LAT 2-year Point Source Catalog

Data.gov (United States)

National Aeronautics and Space Administration — The Fermi Gamma-ray Space Telescope (Fermi) Large Area Telescope (LAT) is a successor to EGRET, with greatly improved sensitivity, resolution, and energy range. This...

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)

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...

P.E.I. wood fuel survey, 1990-91

International Nuclear Information System (INIS)

1991-04-01

In 1991 a wood fuel survey of 450 randomly selected households, representing 1% of the total number of households in Prince Edward Island, was conducted. The survey indicated that 49.8% of the households burned wood, up from 42.1% of households in the 1988-1989 survey. The wood burning households consumed an average of 4.92 cords of wood, consistent with the 4.90 cords in the 1989 survey. The total residential wood consumption was estimated at ca 100,377 cords, an increase from the 89,000 cords used in 1988-89. Wood cutters represented 23.4% of respondents, with buyers representing 25.4% of respondents. The wood burning appliances used by the respondents were: airtight wood stove 39.9%, wood furnace 22.5%, kitchen wood stove 15.7%, combined wood/oil furnace 8.9%, Franklin/non-airtight 4.4%, Kemac unit 4.4%, fireplace insert 3.1%, and open fireplace 1%. The most frequent response among rural wood users cited price as an advantage of wood fuel, while the most frequent response of urban users cited the quality of the heat. 9 figs., 47 tabs

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.

EFFECTS OF BURN RATE, WOOD SPECIES, MOISTURE CONTENT AND WEIGHT OF WOOD LOADED ON WOODSTOVE EMISSIONS

Science.gov (United States)

The report gives results of tests of four woodstove operating parameters (burn rate, wood moisture, wood load, and wood species) at two levels each using a half factorial experimental test design to determine statistically significant effects on the emission components CO, CO2, p...

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...

Energy wood procurement in connection with conventional wood procurement; Energiapuun hankinnan organisointi muun puunhankinnan yhteydessae - PUUT02

Energy Technology Data Exchange (ETDEWEB)

Maekinen, P. [Finnish Forest Research Institute, Vantaa (Finland)

2001-07-01

The research consisted of two sub-projects. The present role of forestry associations in procurement of energy wood was investigated in the first sub- project. The possibilities and willingness of them to increase the energy wood procurement were also studied. The role of forest machine and forestry service entrepreneurs in procurement of energy wood was investigated in the second sub-project. The effects of energy wood procurement on the operation of the forest machine companies in general were also studied in this sub-project. The sub-project three studied the requirements of the customer companies for the energy wood suppliers. All the material of the sub-projects was collected by personal inquiries. According to the executive directors of the forestry associations the role of the forestry associations in energy wood procurement varied between a by-stander and active participant. Active forestry associations announced the companies for stands available for cutting. They told also that they directed the harvesting to correct sites and deliver stems at the roadside. The role of the forestry association was emphasised especially when the associations on the basis of a letter of attorney carried out the timber trade. It was estimated that in the near future the operation of forest machine entrepreneurs in harvesting of energy wood would increase significantly. From the employment and turnover point of view the role of harvesting of energy wood was not seen as a significant matter. On the other hand, that harvesting of energy wood impede the harvesting of commercial timber was seen as a more significant matter. In the future the end-users of energy wood would like to have more competition in the energy wood markets. However, the energy wood suppliers were desired to be relative large so that the reliability of deliveries could be ensured. Simultaneously as the end-users wanted to decrease the price of forest chips, the machine entrepreneurs estimated the price to

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...

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 (...

Effect of Alternative Wood Species and First Thinning Wood on Oriented Strand Board Performance

Directory of Open Access Journals (Sweden)

Fabiane Salles Ferro

2018-01-01

Full Text Available This study aimed to evaluate the feasibility of using and influence of alternative wood species such as Cambará, Paricá, Pinus, and wood from first thinning operations on oriented strand board (OSB physical and mechanical properties. Besides that, an alternative resin, castor oil-based polyurethane, was used to bond the particles, due to the better environmental performance when compared to other resins commonly used worldwide in OSB production. Physical properties such as the moisture content, thickness swelling, and water absorption, both after 2 and 24 hours of water immersion, and mechanical properties such as the modulus of elasticity and resistance in static bending, in major and minor axes, and internal bonding were investigated. All tests were performed according to European code EN 300:2006. Results showed the influence of wood species on physical and mechanical properties. Panels made with higher density woods such as Cambará presented better physical performance, while those made with lower density woods such as Pinus presented better mechanical properties. Besides that, strand particle geometry was also influenced on all physical and mechanical properties investigated. Therefore, the feasibility of using alternative species and wood from first thinning and with castor oil-based polyurethane resin in OSB production was verified.

The environmental assessment of the wood combustion

International Nuclear Information System (INIS)

Dinca, Cristian; Badea, Adrian; Apostol, Tiberiu

2007-01-01

In this paper, the authors analysed the emissions from residential boilers burning wood logs, bark pellets, wood briquettes and wood pellets. Three boilers, selected with respect to age, design, connection to heat storage tank, and type of biofuel, were included in the study. The emissions captured comprised carbon monoxide (CO), carbon dioxide (CO 2 ), oxygen (O 2 ), total organic carbons (TOC), nitrogen oxides (NO x ), polycyclic aromatic hydrocarbons (PAC) and 33 volatile organic compounds (VOC). We have used the Life Cycle Inventory method in order to identify the main stressors generated by the wood combustion stage. In this purpose, we have analysed one type of old boiler, one type of modern boiler and a multi-fuel boiler, which can burn wood logs, bark pellets, wood briquettes and wood pellets. In this article, we selected only the wood combustion stage because it is the most important according to the emissions produced. (authors)

Wood-energy - The sector get worried

International Nuclear Information System (INIS)

Mary, Olivier; Signoret, Stephane; Bohlinger, Philippe; Guilhem, Jean; De Santis, Audrey; Sredojevic, Alexandre; Defaye, Serge; Maindrault, Marc

2017-01-01

Wood energy is, today and certainly also tomorrow, one of the most important renewable energies in France. However, the wood-energy sector seems to slow down as hydrocarbon prices stay extremely low. This document presents 8 articles, describing the context and the characteristics of this evolution, plus some examples of developments in France. The themes of the articles are: the activity of the wood-energy sector should be reinforced to meet the objectives of the French energy multi-year plan; The 2035 prospective of the wood yield in the French forest will meet the future demand, however this evaluation does not take into consideration the effects of the climatic change; the conversion to biomass of the 'Fort de l'Est' (near Paris) heating system (equipped with a boiling fluidized bed boiler) has enabled the heat network to beat the 50 pc share of renewable energy; wood-energy professionals use the 'quality' lever to challenge their fossil fuel competitors; the city of Orleans is now equipped with an innovative biomass cogeneration plant; the example of wood waste valorization in a French sawmill; the French ONF (Forest Administration) Wood-Energy actor has just inaugurated its largest biomass dryer, in order to develop the domestic market for wood as a fuel; analysis of the technical and economical feasibility of using wood to generate electric power or replacing electric space heating by heat network

Coal and wood fuel for electricity production: An environmentally sound solution for waste and demolition wood

Energy Technology Data Exchange (ETDEWEB)

Penninks, F.W.M. [EPON, Zwolle (Netherlands)

1997-12-31

Waste wood from primary wood processing and demolition presents both a problem and a potential. If disposed in landfills, it consumes large volumes and decays, producing CH{sub 4}, CO{sub 2} and other greenhouse gases. As an energy source used in a coal fired power plant it reduces the consumption of fossil fuels reducing the greenhouse effect significantly. Additional advantages are a reduction of the ash volume and the SO{sub 2} and NO{sub x} emissions. The waste wood requires collection, storage, processing and burning. This paper describes a unique project which is carried out in the Netherlands at EPON`s Gelderland Power Plant (635 MW{sub e}) where 60 000 tonnes of waste and demolition wood will be used annually. Special emphasis is given to the processing of the powdered wood fuel. Therefore, most waste and demolition wood can be converted from an environmental liability to an environmental and economic asset. (author)

Coal and wood fuel for electricity production: An environmentally sound solution for waste and demolition wood

Energy Technology Data Exchange (ETDEWEB)

Penninks, F W.M. [EPON, Zwolle (Netherlands)

1998-12-31

Waste wood from primary wood processing and demolition presents both a problem and a potential. If disposed in landfills, it consumes large volumes and decays, producing CH{sub 4}, CO{sub 2} and other greenhouse gases. As an energy source used in a coal fired power plant it reduces the consumption of fossil fuels reducing the greenhouse effect significantly. Additional advantages are a reduction of the ash volume and the SO{sub 2} and NO{sub x} emissions. The waste wood requires collection, storage, processing and burning. This paper describes a unique project which is carried out in the Netherlands at EPON`s Gelderland Power Plant (635 MW{sub e}) where 60 000 tonnes of waste and demolition wood will be used annually. Special emphasis is given to the processing of the powdered wood fuel. Therefore, most waste and demolition wood can be converted from an environmental liability to an environmental and economic asset. (author)

Mineralogy of Non-Silicified Fossil Wood

Directory of Open Access Journals (Sweden)

George E. Mustoe

2018-03-01

Full Text Available The best-known and most-studied petrified wood specimens are those that are mineralized with polymorphs of silica: opal-A, opal-C, chalcedony, and quartz. Less familiar are fossil woods preserved with non-silica minerals. This report reviews discoveries of woods mineralized with calcium carbonate, calcium phosphate, various iron and copper minerals, manganese oxide, fluorite, barite, natrolite, and smectite clay. Regardless of composition, the processes of mineralization involve the same factors: availability of dissolved elements, pH, Eh, and burial temperature. Permeability of the wood and anatomical features also plays important roles in determining mineralization. When precipitation occurs in several episodes, fossil wood may have complex mineralogy.

Recycling of wood products. Final report of the preliminary study project partly financed by the Finnish Wood Research Oy; Puutuotteiden kierraetys. Finnish Wood Research Oy:n osarahoittaman esiselvityshankkeen loppuraportti

Energy Technology Data Exchange (ETDEWEB)

Pirhonen, I.; Heraejaervi, H.; Saukkola, P.; Raety, T.; Verkasalo, E., Email: henrik.herajarvi@metla.fi

2011-07-01

The objective of this preliminary study was to clarify the present state of recycling of wood in Finland and Europe. In the work the control measures of recycling were examined. In Finland there will be a total amount of 850 000 tons of waste wood per year. Of this amount 670 000 tons is from construction and demolishing of buildings. Burning the wood to energy is technically and economically the most reasonable use of waste wood in Finland and in several other European countries where there is a long heating season. A lot of work has been done to find new ways of utilization. The objective of the European Union to increase the use of renewable natural resources in the energy production creates an additional demand to all kinds of wood, including waste wood. The waste legislation of Finland and EU is directing to recycling, not restricting it. Furthermore, the systems to try to create markets for products containing recycled materials are under development. In the future it is expected that the legislation is tightening and the burning of waste wood is no longer calculated as acceptable recycling. Other ways to utilize wood waste should then already be developed. Furthermore, the development and introduction of new recycling methods are of important significance also when marketing wood and wood products. The recycling should be taken into consideration already at the planning stage of the building

Surface characterization of weathered wood-plastic composites produced from modified wood flour

Science.gov (United States)

James S. Fabiyi; Armando G. McDonald; Nicole M. Stark

2007-01-01

The effects of weathering on the surface properties of wood-plastic composites (WPC) were examined. High-density polyethylene (HDPE) based WPCs made from modified wood flour (untreated, extractives free, and holocellulose (delignified) fibers) were subjected to accelerated (xenon-arc) weathering. Colorimetry and Fourier-transform infrared spectroscopy were employed to...

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

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.

Chapter 6: Above Ground Deterioration of Wood and Wood-Based Materials

Science.gov (United States)

Grant Kirker; Jerrold Winandy

2014-01-01

Wood as a material has unique properties that make it ideal for above ground exposure in a wide range of structural and non-strucutral applications. However, no material is without limitations. Wood is a bio-polymer which is subject to degradative processes, both abiotic and biotic. This chapter is a general summary of the abiotic and biotic factors that impact service...

X-ray initiated polymerization of wood impregnants

Energy Technology Data Exchange (ETDEWEB)

Cleland, Marshall R.; Galloway, Richard A. [IBA Industrial, Inc., Edgewood, NY (United States); Berejka, Anthony J. [Ionicorp, Huntington, NY 11743 (United States)], E-mail: berejka@msn.com; Montoney, Daniel [Strathmore Products, Syracuse, NY (United States); Driscoll, Mark; Smith, Leonard; Scott Larsen, L. [State University of New York, SUNY-ESF, Syracuse, NY (United States)

2009-07-15

X-rays, derived from a high energy, high-current electron beam (EB), initiated in-situ polymerization of a unique class of monomers that were found to penetrate the cell walls of wood. X-rays initiated an auto-catalytic acrylic polymerization and penetrated through thick pieces of wood. The final cured product having the polymerizate, a polymer, both in the wood cell lumens and in the cell walls is called wood impregnated with a wood-polymer penetrant (WPP). The controlled lower dose rate of X-rays overcame disproportionation encountered when using higher dose-rate electron beam initiation. With X-rays, the in-situ polymerization took place in one exposure of modest dose. With EB, multiple passes were needed to avoid excessive heat build-up and monomer volatilization. Having entered the cell walls of the wood and then being polymerized within the cell walls, these radiation-cured unique monomers imparted outstanding dimensional stability upon exposure of the impregnated wood to humidity cycling. The preferred monomer system was also chemically modified prior to impregnation with agents that would remain in the wood and prevent the growth of fungi and other microbials. This technique differs from historic uses of monomers that merely filled the lumens of the wood (historic wood-polymer composites), which are only suitable for indoor use. The WPP impregnated wood that was either X-ray cured or EB cured demonstrated enhanced structural properties, dimensional stability, and decay resistance.

X-ray initiated polymerization of wood impregnants

International Nuclear Information System (INIS)

Cleland, Marshall R.; Galloway, Richard A.; Berejka, Anthony J.; Montoney, Daniel; Driscoll, Mark; Smith, Leonard; Scott Larsen, L.

2009-01-01

X-rays, derived from a high energy, high-current electron beam (EB), initiated in-situ polymerization of a unique class of monomers that were found to penetrate the cell walls of wood. X-rays initiated an auto-catalytic acrylic polymerization and penetrated through thick pieces of wood. The final cured product having the polymerizate, a polymer, both in the wood cell lumens and in the cell walls is called wood impregnated with a wood-polymer penetrant (WPP). The controlled lower dose rate of X-rays overcame disproportionation encountered when using higher dose-rate electron beam initiation. With X-rays, the in-situ polymerization took place in one exposure of modest dose. With EB, multiple passes were needed to avoid excessive heat build-up and monomer volatilization. Having entered the cell walls of the wood and then being polymerized within the cell walls, these radiation-cured unique monomers imparted outstanding dimensional stability upon exposure of the impregnated wood to humidity cycling. The preferred monomer system was also chemically modified prior to impregnation with agents that would remain in the wood and prevent the growth of fungi and other microbials. This technique differs from historic uses of monomers that merely filled the lumens of the wood (historic wood-polymer composites), which are only suitable for indoor use. The WPP impregnated wood that was either X-ray cured or EB cured demonstrated enhanced structural properties, dimensional stability, and decay resistance.

Dendro-chronological analysis of fossilised wood in order to reconstruct the post-ice-age history of glaciers; Dendrochronologische Auswertung fossiler Hoelzer zur Rekonstruktion der nacheiszeitlichen Gletschergeschichte

Energy Technology Data Exchange (ETDEWEB)

Holzhauser, H.

2008-07-01

Around the middle of the 19th century, alpine glaciers advanced to their last maximum extension within the Holocene (the last 11'600 years). Some of the glaciers, especially the Great Aletsch and Gorner, penetrated deeply into wooded land and destroyed numerous trees. Not only were trees destroyed but also valuable arable farmland, alpine farm buildings and dwelling houses. Since the last maximum extension in the 19th century the retreat of the glaciers has accelerated revealing, within the glacier forefields, the remainders of trees once buried. Some of this fossil wood is found in the place where it grew (in situ). Often the wood dates back to a time before the last glacier advance, most of it is several thousands of years old because glacial advance and retreat periods occurred repeatedly within the Holocene. This paper shows the characteristics of fossil wood and how it can be analysed to reconstruct glacial history. It will be demonstrated how glacier length variation can be exactly reconstructed with help of dendrochronology. Thanks to the very exact reconstruction of the glacier length change during the advance periods in the 14th and 16th centuries, the velocities of both the Gorner and Great Aletsch glaciers can be estimated. They range between 7-8 and 20 m per year, in the case of the Gorner glacier, and between 7-8 and 36 m per year, in the case of the Great Aletsch glacier. (author)

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.

The economic potential of wood pellet production from alternative, low-value wood sources in the southeast of the US

NARCIS (Netherlands)

Hoefnagels, Ric; Junginger, Martin; Faaij, Andre

2014-01-01

The global demand for wood pellets used for energy purposes is growing. Therefore, increased amounts of wood pellets are produced from primary forestry products, such as pulp wood. The present analysis demonstrates that substantial amounts of alternative, low-value wood resources are available that

Users guide for WoodCite, a product cost quotation tool for wood component manufacturers [computer program

Science.gov (United States)

Jeff Palmer; Adrienn Andersch; Jan Wiedenbeck; Urs. Buehlmann

2014-01-01

WoodCite is a Microsoft® Access-based application that allows wood component manufacturers to develop product price quotations for their current and potential customers. The application was developed by the U.S. Forest Service and Virginia Polytechnic Institute and State University, in cooperation with the Wood Components Manufacturers Association.

Wood energy x 2 - Scenario for the development of wood energy use in Switzerland

International Nuclear Information System (INIS)

2004-01-01

This study for the Swiss Agency for the Environment, Forests and Landscapes (SAEFL) and the Swiss wood-energy association (Holzenergie Schweiz) presents the results of a scenario-study that examined if, and under what conditions, doubling the use of wood energy in Switzerland could help reach carbon dioxide reduction targets. Two scenarios are presented that are based on high and low rates of growth for the number of automatic wood-chipping or pellets-fired installations. For both scenarios, figures are presented on the amount of wood used and the heating energy generated. The political and financial prerequisites for the scenarios are discussed and other boundary conditions are defined. The report draws conclusions from the study of the two scenarios and summarises the political action deemed necessary

Implementation of new technologies in wood industry and their effect in wood products quality

OpenAIRE

ELVA ÇAUSHI; PANDELI MARKU

2014-01-01

There are about 300 companies producing furniture and about 250 small and medium enterprises (SME) producing sawn timber, which operate in the field of wood industry in Albania. This wood industry production is being challenged by the increasing demand in the domestic market, ranging from kitchen furniture to office and schools furniture, bedroom furniture, doors, windows, and saw timber in different dimensions. The production from the wood industry can fulfill about 80% of the domestic mark...

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)

Wood for fuel

Energy Technology Data Exchange (ETDEWEB)

Beaton, D

1986-01-01

Growing wood for energy could contribute three million tonnes of coal equivalent per year by the end of the century. Research programmes in the UK involved with energy forestry are reported. Three systems of wood energy, modified conventional forestry, single stem timber cropping and short rotation coppicing are being investigated. The short rotation coppicing requires inputs similar to those of agricultural crops and the machinery geared towards agricultural operations is compatible with it. Single stem forestry has a medium rotation period of 20 years. The production of coppice wood fuels is discussed in further detail for different parts of the UK with recommendations for species selection and adaption of existing farming practices. A coppice willow harvester has been developed for harvesting during November - February. Weed control and fertilizer application are also briefly mentioned.

The Swedish wood fuel market

International Nuclear Information System (INIS)

Hillring, Bengt

1999-01-01

In Sweden, wood fuels are traditionally used in the Swedish forest products industry and for heating of single-family houses. More recently they are also become established as an energy source for district heating and electricity production. Energy policy, especially the energy taxation system, has favoured wood fuels and other biofuels, mainly for environmental reasons. There is now an established commercial market for wood fuels in the district heating sector, which amounts to 45 PJ and is growing 20 per cent annually. Price levels have been stable in current prices for a decade, mainly because of good access to wood fuels. Price levels are dominated by production costs on a market that is largely governed by the buyer. It is expected that the use of wood fuels will increased in Sweden in the future, which will push a further development of this section on the market and bring about technological changes in the area. (Author)

Population structure of Argas arboreus (Acari : Argasidae ticks associated with seasonally abandoned mixed heronries, dominated by cattle egrets (Bubulcus ibis, in South Africa

Directory of Open Access Journals (Sweden)

V.N. Belozerov

2003-11-01

Full Text Available During winter populations of Argas arboreus from heronries of the cattle egret, Bubulcus ibis, in South Africa are composed of adults, with some predominance of males, and II-IV instar nymphs, in a state of diapause. The period of tick activity, including reproduction and development of eggs, larvae and N1 nymphs, is synchronized with the nesting and breeding season of their avian hosts. It begins during spring with the return of birds to the heronry, and ceases in autumn through induction of reproductive diapause in engorged females, and behavioural diapause in unfed nymphs and adult ticks. Many ticks showed morphological anomalies and malformations, the study of which could possibly be used for monitoring of environmental pollution.

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...

Wood and Sediment Dynamics in River Corridors

Science.gov (United States)

Wohl, E.; Scott, D.

2015-12-01

Large wood along rivers influences entrainment, transport, and storage of mineral sediment and particulate organic matter. We review how wood alters sediment dynamics and explore patterns among volumes of instream wood, sediment storage, and residual pools for dispersed pieces of wood, logjams, and beaver dams. We hypothesized that: volume of sediment per unit area of channel stored in association with wood is inversely proportional to drainage area; the form of sediment storage changes downstream; sediment storage correlates most strongly with wood load; and volume of sediment stored behind beaver dams correlates with pond area. Lack of data from larger drainage areas limits tests of these hypotheses, but analyses suggest a negative correlation between sediment volume and drainage area and a positive correlation between wood and sediment volume. The form of sediment storage in relation to wood changes downstream, with wedges of sediment upstream from jammed steps most prevalent in small, steep channels and more dispersed sediment storage in lower gradient channels. Use of a published relation between sediment volume, channel width, and gradient predicted about half of the variation in sediment stored upstream from jammed steps. Sediment volume correlates well with beaver pond area. Historically more abundant instream wood and beaver populations likely equated to greater sediment storage within river corridors. This review of the existing literature on wood and sediment dynamics highlights the lack of studies on larger rivers.

Management alternatives of energy wood thinning stands

International Nuclear Information System (INIS)

Heikkilae, Jani; Siren, Matti; Aeijaelae, Olli

2007-01-01

Energy wood thinning has become a feasible treatment alternative of young stands in Finland. Energy wood thinnings have been carried out mainly in stands where precommercial thinning has been neglected and the harvesting conditions for industrial wood thinning are difficult. Despite of its positive effects on harvesting costs and on renewable energy potential, whole-tree harvesting has been constantly criticized for causing growth loss. In this paper, the profitability of energy wood thinning was studied in 20 Scots pine-dominated stands where energy wood thinning was carried out. The growth of the stands after thinning was predicted with the help of Motti-stand simulator. Entire rotation time of the stands was simulated with different management alternatives. The intensity of first thinning and recovery level of logging residues varied between alternatives. In order to attain acceptable harvesting conditions, industrial wood thinning had to be delayed. The effect of energy wood thinning on subsequent stem wood growth was almost the same as in conventional thinning. Whole-tree harvesting for energy proved to be profitable alternative if the stumpage price is around 3EUR m -3 , the interest rate is 3% or 5% and the removal of pulpwood is less than 20 m 3 ha -1 . If the harvestable pulpwood yield is over 20 m 3 ha -1 , integrated harvesting of industrial and energy wood or delayed industrial wood harvesting becomes more profitable. (author)

Impregnating Systems for Producing Wood-Plastic Composite Materials and Resinified Woods by Radiochemical Means

International Nuclear Information System (INIS)

Laizier, J.; Laroche, R.; Marchand, J.

1969-01-01

The effect of the nature of the components in the impregnation mixture on the characteristics of wood-plastic combinations has been studied in the case of beech by applying a wide variety of compositions. In particular, the effect of water (in the impregnator, and in the form of moisture in the wood) on the characteristics of the products obtained has been determined. It has been shown that, in place of the conventional method for preparing resinified woods (using a ternary monomer-solvent-water mixture), it is possible to use a method involving comonomers, which obviate the need to dry the wood after treatment. The evaluation of the results obtained is based on the value of the impregnation rate and on the modifications in microscopic structure; these emphasize the differences between the types of filler and enable comparisons to be drawn with the dimensional stabilities observed. Measurements of variations in dimensions and the recurrence of moisture have made it possible to establish a classification based on the types of monomer used and the operating conditions. It is shown that a whole range of products is obtained, the properties of which differ widely and are comparatively easily adaptable to the purpose specified. These properties illustrate clearly the differences and characteristics of resinified woods as opposed to conventional wood-plastic materials. (author) [fr

NorWood: a gene expression resource for evo-devo studies of conifer wood development.

Science.gov (United States)

Jokipii-Lukkari, Soile; Sundell, David; Nilsson, Ove; Hvidsten, Torgeir R; Street, Nathaniel R; Tuominen, Hannele

2017-10-01

The secondary xylem of conifers is composed mainly of tracheids that differ anatomically and chemically from angiosperm xylem cells. There is currently no high-spatial-resolution data available profiling gene expression during wood formation for any coniferous species, which limits insight into tracheid development. RNA-sequencing data from replicated, high-spatial-resolution section series throughout the cambial and woody tissues of Picea abies were used to generate the NorWood.conGenIE.org web resource, which facilitates exploration of the associated gene expression profiles and co-expression networks. Integration within PlantGenIE.org enabled a comparative regulomics analysis, revealing divergent co-expression networks between P. abies and the two angiosperm species Arabidopsis thaliana and Populus tremula for the secondary cell wall (SCW) master regulator NAC Class IIB transcription factors. The SCW cellulose synthase genes (CesAs) were located in the neighbourhoods of the NAC factors in A. thaliana and P. tremula, but not in P. abies. The NorWood co-expression network enabled identification of potential SCW CesA regulators in P. abies. The NorWood web resource represents a powerful community tool for generating evo-devo insights into the divergence of wood formation between angiosperms and gymnosperms and for advancing understanding of the regulation of wood development in P. abies. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

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

Wood Cellular Dendroclimatology: A Pilot Study on Bristlecone Pine in the Southwest US

Science.gov (United States)

Ziaco, E.; Biondi, F.; Heinrich, I.

2015-12-01

Tree-rings provide paleoclimatic records at annual to seasonal resolution for regions or periods with no instrumental climatic data. Relationships between climatic variability and wood cellular features allow for a more complete understanding of the physiological mechanisms that control the climatic response of trees. Given the increasing importance of wood anatomy as a source of dendroecological information, such studies are now starting in the US. We analyzed 10 cores of bristlecone pine (Pinus longaeva D.K. Bailey) from a high-elevation site included in the Nevada Climate-ecohydrological Assessment Network (NevCAN). Century-long chronologies (1870-2013) of wood anatomical parameters (lumen area, cell diameter, cell wall thickness) can be developed by capturing strongly contrasted microscopic images using a Confocal Laser Scanning Microscope, and then measuring cellular parameters with task-specific software. Measures of empirical signal strength were used to test the strength of the environmental information embedded in wood anatomy. Correlation functions between ring-width, cellular features, and PRISM climatic variables were produced for the period 1926-2013. Time series of anatomical features present lower autocorrelation compared to ring widths, highlighting the role of environmental conditions occurring at the time of cell formation. Mean chronologies of radial lumen length and cell diameter carry a stronger climatic signal compared to cell wall thickness, and are significantly correlated with climatic variables (maximum temperature and total precipitation) in spring (Mar-Apr) and during the growing season (Jun-Sep), whereas ring widths show weaker or no correlation. Wood anatomy holds great potential to refine dendroclimatic reconstructions at higher temporal resolution, providing better estimates of hydroclimatic variability and plant physiological adaptations in the southwest US.

Assessment and management of dead-wood habitat

Science.gov (United States)

Hagar, Joan

2007-01-01

The Bureau of Land Management (BLM) is in the process of revising its resource management plans for six districts in western and southern Oregon as the result of the settlement of a lawsuit brought by the American Forest Resource Council. A range of management alternatives is being considered and evaluated including at least one that will minimize reserves on O&C lands. In order to develop the bases for evaluating management alternatives, the agency needs to derive a reasonable range of objectives for key issues and resources. Dead-wood habitat for wildlife has been identified as a key resource for which decision-making tools and techniques need to be refined and clarified. Under the Northwest Forest Plan, reserves were to play an important role in providing habitat for species associated with dead wood (U.S. Department of Agriculture Forest Service and U.S. Department of the Interior Bureau of Land Management, 1994). Thus, the BLM needs to: 1) address the question of how dead wood will be provided if reserves are not included as a management strategy in the revised Resource Management Plan, and 2) be able to evaluate the effects of alternative land management approaches. Dead wood has become an increasingly important conservation issue in managed forests, as awareness of its function in providing wildlife habitat and in basic ecological processes has dramatically increased over the last several decades (Laudenslayer et al., 2002). A major concern of forest managers is providing dead wood habitat for terrestrial wildlife. Wildlife in Pacific Northwest forests have evolved with disturbances that create large amounts of dead wood; so, it is not surprising that many species are closely associated with standing (snags) or down, dead wood. In general, the occurrence or abundance of one-quarter to one-third of forest-dwelling vertebrate wildlife species, is strongly associated with availability of suitable dead-wood habitat (Bunnell et al., 1999; Rose et al., 2001). In

Radiation processing of wood-plastic composites

International Nuclear Information System (INIS)

Czvikovszky, T.

1992-01-01

There are three main types of radiation-processed composite material derived from plastics and fibrous natural polymers. The first are the monomer-impregnated, radiation-treated wood-plastic composites (WPC). They became a commercial success in the early 1970s. More recently, work has focused on improving the WPCs by creating in them interpenetrating network (IPN) systems by the use of appropriate multifunctional oligomers and monomers. The main kinetic features of radiation-initiated chain polymerization remain applicable even in impregnated wood. The second type are the plastics filled or reinforced with dispersed wood fiber or other cellulosics (WFRP). In their case, radiation processing offers a new opportunity to apply radiation-reactive adhesion promoters between wood or cellulosic fibers and the thermoplastic matrices. The third type are the laminar composites made by electron beam coating of wood-based agglomerate sheets and boards. This chapter reviews the industrial applications and the radiation processing of the three types of the wood-plastic composites and indicates future trends. (orig.)

Long term durability of wood-plastic composites made with chemically modified wood

Science.gov (United States)

Rebecca E. Ibach; Craig M. Clemons

2017-01-01

Wood-plastic composites (WPCs) have slower moisture sorption than solid wood, but over time moisture can impact the strength, stiffness, and decay of the composite. These changes will become increasingly important if WPCs are used in more challenging environments such as in ground-contact applications. There are several options for mitigating the moisture sorption of...

Simulated long-term effects of varying tree retention on wood production, dead wood and carbon stock changes.

Science.gov (United States)

Santaniello, Francesca; Djupström, Line B; Ranius, Thomas; Weslien, Jan; Rudolphi, Jörgen; Sonesson, Johan

2017-10-01

Boreal forests are an important source of timber and pulp wood, but provide also other products and services. Utilizing a simulation program and field data from a tree retention experiment in a Scots pine forest in central Sweden, we simulated the consequences during the following 100 years of various levels of retention on production of merchantable wood, dead wood input (as a proxy for biodiversity), and carbon stock changes. At the stand level, wood production decreased with increased retention levels, while dead wood input and carbon stock increased. We also compared 12 scenarios representing a land sharing/land sparing gradient. In each scenario, a constant volume of wood was harvested with a specific level of retention in a 100-ha landscape. The area not needed to reach the defined volume was set-aside during a 100-year rotation period, leading to decreasing area of set-asides with increasing level of retention across the 12 scenarios. Dead wood input was positively affected by the level of tree retention whereas the average carbon stock decreased slightly with increasing level of tree retention. The scenarios will probably vary in how they favor species preferring different substrates. Therefore, we conclude that a larger variation of landscape-level conservation strategies, also including active creation of dead wood, may be an attractive complement to the existing management. Copyright © 2017 Elsevier Ltd. All rights reserved.

Substitution potentials of recycled HDPE and wood particles from post-consumer packaging waste in Wood-Plastic Composites.

Science.gov (United States)

Sommerhuber, Philipp F; Welling, Johannes; Krause, Andreas

2015-12-01

The market share of Wood-Plastic Composites (WPC) is small but expected to grow sharply in Europe. This raises some concerns about suitable wood particles needed in the wood-based panels industry in Europe. Concerns are stimulated by the competition between the promotion of wooden products through the European Bioeconomy Strategy and wood as an energy carrier through the Renewable Energy Directive. Cascade use of resources and valorisation of waste are potential strategies to overcome resource scarcity. Under experimental design conditions, WPC made from post-consumer recycled wood and plastic (HDPE) were compared to WPC made from virgin resources. Wood content in the polymer matrix was raised in two steps from 0% to 30% and 60%. Mechanical and physical properties and colour differences were characterized. The feasibility of using cascaded resources for WPC is discussed. Results indicate the technical and economic feasibility of using recycled HDPE from packaging waste for WPC. Based on technical properties, 30% recycled wood content for WPC is feasible, but economic and political barriers of efficient cascading of biomass need to be overcome. Copyright © 2015 Elsevier Ltd. All rights reserved.

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.

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...... with nanometal oxides that allow wood texture to remain seen and higher resilience to scratch and abrasion with use of different nanoparticle shapes are some of the applications that are reviewed here. A variety of possible applications together with a high level of improvements, alongside commercial factors...... like a low level of loading, have already established nanoparticles in some areas of wood coatings. This article is a comprehensive scientific review of the published work in the use of nanofillers in wood coatings....

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...

Adhesives for Achieving Durable Bonds with Acetylated Wood

Science.gov (United States)

Charles Frihart; Rishawn Brandon; James Beecher; Rebecca Ibach

2017-01-01

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...

Comparative study on liquefaction of creosote and chromated copper arsenate (CCA)-treated wood and untreated southern pine wood: effects of acid catalyst content, liquefaction time, temperature, and phenol to wood ratio

Science.gov (United States)

Hui Pan; Chung-Yun Hse; Todd F. Shupe

2009-01-01

Creosote- and chromated copper arsenate (CCA)-treated wood waste and untreated southern pine wood were liquefied with phenol and sulfuric acid. The effects of sulfuric acid content, liquefaction time, liquefaction temperature, and phenol to wood ratio on liquefaction rate (i.e., wood residue content) were investigated and analyzed by analysis of variance (...

Method of stabilizing wood

International Nuclear Information System (INIS)

Pesek, M.; Jarkovsky, J.

1973-01-01

Wood is impregnated with a mixture of a vinyl or an allyl monomer (20 - 90 wt. %) and unsaturated polyester resins. The impregnated wood is then exposed to ionizing radiation at doses of 0.1 to 20 Mrad at a temperature of 60 to 180 degC. (B.S.)

Switzerland's largest wood-pellet factory in Balsthal

International Nuclear Information System (INIS)

Stohler, F.

2004-01-01

This article describes how a small Swiss electricity utility has broken out of its traditional role in power generation and the distribution of electricity and gone into the production of wood pellets. The pellets, which are made from waste wood (sawdust) available from wood processing companies, are produced on a large scale in one of Europe's largest pellets production facilities. The boom in the use of wood pellets for heating purposes is discussed. The article discusses this unusual approach for a Swiss power utility, which also operates a wood-fired power station and is even involved in an incineration plant for household wastes. The markets being aimed for in Switzerland and in Europe are described, including modern low-energy-consumption housing projects. A further project is described that is to use waste wood available from a large wood processing facility planned in the utility's own region

Preparation and applications of wood-polyester composites

International Nuclear Information System (INIS)

Czvikovszky, T.

1982-01-01

Optimum processing parameters were searched for the pilot-scale production of wood-polyester composites by irradiation of resin-impregnated wood material. The radiation initiation of the following systems were examined in wood and without wood matrix: methyl methacrylate, mixture of styrene and acrylonitryle, and their combination with unsaturated polyester. In the most cases the over-all rate of the complete polymerization process in wood matrix is proportional to the square root of the initiation rate. The parameters of the radiation technology of wood-polyester composites have been determined, using 260 TBq (7 kCi) 60 Co radiation source. A pilot plant has been constructed using an underwater irradiation system of 1.85 PBq (50 kCi) 60 Co. The successful production rate of 200 kg wood-polyester composite per day, as well as the application tests have demonstrated the technical feasibility of this new structural material. (author)

RESISTANCE TO THE ATTACK OF DRY-WOOD TERMITES (Cryptotermes brevis) OF SIX WOOD SPECIES

OpenAIRE

Fabrício Gomes Gonçalves; José Tarcísio da Silva Oliveira

2006-01-01

The dry wood termites are one of the largest causes of damages in wood used in Brazil. This work analyzed the attackof the Cryptotermes brevis in six commercials wood species in the north of the Rio de Janeiro and south of the Espírito Santo. The testobserved the number of holes, the percentage of died individuals and the damage of the pieces. When compared to the Pinus sp(reference), the species with less susceptibility to the attack were Cedrela fissilis, Cariocar brasiliense and Goupia gla...

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...

Wood for sound.

Science.gov (United States)

Wegst, Ulrike G K

2006-10-01

The unique mechanical and acoustical properties of wood and its aesthetic appeal still make it the material of choice for musical instruments and the interior of concert halls. Worldwide, several hundred wood species are available for making wind, string, or percussion instruments. Over generations, first by trial and error and more recently by scientific approach, the most appropriate species were found for each instrument and application. Using material property charts on which acoustic properties such as the speed of sound, the characteristic impedance, the sound radiation coefficient, and the loss coefficient are plotted against one another for woods. We analyze and explain why spruce is the preferred choice for soundboards, why tropical species are favored for xylophone bars and woodwind instruments, why violinists still prefer pernambuco over other species as a bow material, and why hornbeam and birch are used in piano actions.

Moisture measurement in wood, wood-based materials and building materials - a literature review

International Nuclear Information System (INIS)

Kober, A.; Mehlhorn, L.; Plinke, B.

1989-10-01

Methods of moisture measurement in solid substances, especially on wood, wood-based materials and building materials were examined and evaluated according to the literature available. The question was which methods of examining the moisture distribution in building elements at climate loading offer the best accuracy and spatial resolution as well as which methods are the most appropriate at present and in future for the solution of measurement problems in the wood and wood-based industry. The most common methods are electric measurement methods which are utilizing either the moisture-depending conductivity or the dielectric constant or the reflectivity of the material for infrared radiation but they offer only a limited accuracy. The same is valid for the rarely used microwave methods or X-ray and NMR tomography. Simple electric methods will further on play an important role in the industrial process measuring technique. For the examination of building elements, methods using nuclear radiation still offer possibilities for a further development. (orig.) With 207 refs., 13 figs [de

Respiratory symptoms and lung function in relation to wood dust and monoterpene exposure in the wood pellet industry.

Science.gov (United States)

Löfstedt, Håkan; Hagström, Katja; Bryngelsson, Ing-Liss; Holmström, Mats; Rask-Andersen, Anna

2017-06-01

Wood pellets are used as a source of renewable energy for heating purposes. Common exposures are wood dust and monoterpenes, which are known to be hazardous for the airways. The purpose of this study was to study the effect of occupational exposure on respiratory health in wood pellet workers. Thirty-nine men working with wood pellet production at six plants were investigated with a questionnaire, medical examination, allergy screening, spirometry, and nasal peak expiratory flow (nasal PEF). Exposure to wood dust and monoterpenes was measured. The wood pellet workers reported a higher frequency of nasal symptoms, dry cough, and asthma medication compared to controls from the general population. There were no differences in nasal PEF between work and leisure time. A lower lung function than expected (vital capacity [VC], 95%; forced vital capacity in 1 second [FEV 1 ], 96% of predicted) was noted, but no changes were noted during shifts. There was no correlation between lung function and years working in pellet production. Personal measurements of wood dust at work showed high concentrations (0.16-19 mg/m 3 ), and exposure peaks when performing certain work tasks. Levels of monoterpenes were low (0.64-28 mg/m 3 ). There was no association between exposure and acute lung function effects. In this study of wood pellet workers, high levels of wood dust were observed, and that may have influenced the airways negatively as the study group reported upper airway symptoms and dry cough more frequently than expected. The wood pellet workers had both a lower VC and FEV 1 than expected. No cross-shift changes were found.

Application of a CCA-treated wood waste decontamination process to other copper-based preservative-treated wood after disposal

Energy Technology Data Exchange (ETDEWEB)

Janin, Amelie, E-mail: amelie.janin@ete.inrs.ca [University of Toronto, Faculty of Forestry, 33, Willcocks St., Toronto, ON, M5S 3B3 (Canada); Coudert, Lucie, E-mail: lucie.coudert@ete.inrs.ca [Institut national de la recherche scientifique (Centre Eau, Terre et Environnement), Universite du Quebec, 490 rue de la Couronne, Quebec, QC, G1K 9A9 (Canada); Riche, Pauline, E-mail: pauline.riche@ete.inrs.ca [Institut national de la recherche scientifique (Centre Eau, Terre et Environnement), Universite du Quebec, 490 rue de la Couronne, Quebec, QC, G1K 9A9 (Canada); Mercier, Guy, E-mail: guy_mercier@ete.inrs.ca [Institut national de la recherche scientifique (Centre Eau, Terre et Environnement), Universite du Quebec, 490 rue de la Couronne, Quebec, QC, G1K 9A9 (Canada); Cooper, Paul, E-mail: p.cooper@utoronto.ca [University of Toronto, Faculty of Forestry, 33, Willcocks St., Toronto, ON, M5S 3B3 (Canada); Blais, Jean-Francois, E-mail: blaisjf@ete.inrs.ca [Institut national de la recherche scientifique (Centre Eau, Terre et Environnement), Universite du Quebec, 490 rue de la Couronne, Quebec, QC, G1K 9A9 (Canada)

2011-02-28

Research highlights: {yields} This paper describes a process for the metal removal from treated (CA-, ACQ- or MCQ-) wood wastes. {yields} This sulfuric acid leaching process is simple and economic. {yields} The remediated wood could be recycled in the industry. - Abstract: Chromated copper arsenate (CCA)-treated wood was widely used until 2004 for residential and industrial applications. Since 2004, CCA was replaced by alternative copper preservatives such as alkaline copper quaternary (ACQ), copper azole (CA) and micronized copper quaternary (MCQ), for residential applications due to health concerns. Treated wood waste disposal is becoming an issue. Previous studies identified a chemical process for decontaminating CCA-treated wood waste based on sulfuric acid leaching. The potential application of this process to wood treated with the copper-based preservatives (alkaline copper quaternary (ACQ), copper azole (CA) and micronized copper quaternary (MCQ)) is investigated here. Three consecutive leaching steps with 0.1 M sulfuric acid at 75 deg, C for 2 h were successful for all the types of treated wood and achieved more than 98% copper solubilisation. The different acidic leachates produced were successively treated by coagulation using ferric chloride and precipitation (pH = 7) using sodium hydroxide. Between 94 and 99% of copper in leachates could be recovered by electrodeposition after 90 min using 2 A electrical current. Thus, the process previously developed for CCA-treated wood waste decontamination could be efficiently applied for CA-, ACQ- or MCQ-treated wood.

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...

Weathering methods for preservative treated wood and their applicability for fire retarded wood

NARCIS (Netherlands)

Voss, A.

1999-01-01

preservative treated wood. The aim of the presentation is to inform you about current testing methods and to discuss their applicability to test fire retarded wood in outdoor use. Assuming that fire retardants will only be used in out of ground contact, only those methods are mentioned, which fit

Wood Export and Deposition Dynamics in Mountain Watersheds

Science.gov (United States)

Senter, Anne Elizabeth

Wood dynamics that store, transport, break down, and ultimately export wood pieces through watershed networks are key elements of stream complexity and ecosystem health. Efforts to quantify wood processes are advancing rapidly as technological innovations in field data collection, remotely sensed data acquisition, and data analyses become increasingly sophisticated. The ability to extend the temporal and spatial scales of wood data acquisition has been particularly useful to the investigations presented herein. The primary contributions of this dissertation are focused on two aspects of wood dynamics: watershed-scale wood export processes as identified using the depositional environment of a mountain reservoir, and wood deposition mechanisms in a bedrock-dominated mountain river. Three chapters present this work: In Chapter 1, continuous video monitoring of wood in transport revealed seasonal and diurnal hydrologic cycle influences on the variable rates at which wood transports. This effort supports the efficacy of utilizing continuous data collection methods for wood transport studies. Annual wood export data were collected via field efforts and aerial image analyses from New Bullards Bar Reservoir on the North Yuba River, Sierra Nevada, California. Examination of data revealed linkages between decadal-scale climatic patterns, large flood events, and episodic wood export quantities. A watershed-specific relation between wood export quantities and annual peak discharge contributes to the notion that peak discharge is a primary control on wood export, and yielded prediction of annual wood export quantities where no data were available. Linkages between seasonality, climatic components, and hydrologic events that exert variable control on watershed scale wood responses are presented as a functional framework. An accompanying conceptual model supports the framework presumption that wood responses are influenced by seasonal variations in Mediterranean-montane climate

Wood quality changes caused by mineral fertilization

Directory of Open Access Journals (Sweden)

Carlos Roberto Sette Jr

2014-06-01

Full Text Available The diverse and important use of wood from fast growth eucalyptus plantations requires the analysis of the effect of mineral fertilizers on wood quality. The objective of this study was to evaluate the anatomical characteristics and wood density from Eucalyptus grandis trees (3 m x 2 m spacing fertilized with potassium and sodium (at planting, 6 th and 12th month. Fifteen (15 6 years old eucalyptus trees were selected (5 trees/treatment, cut and wood samples at DBH (1,3 m were taken for anatomical characteristics (fiber and vessels and wood density analysis. Results showed that eucalyptus trees treated with mineral fertilizers did not show significant alteration in average wood density, with radial profile model common to all three treatments, characterized by a values increase in the region next to the pith, toward to bark. Mineral fertilization influenced wood anatomical characteristics: treatment with sodium was characterized by thinner walls and lumen larger diameter; in treatment with potassium, larger vessels were detected.

Micron-scale intra-ring analyses of δ13C in early Eocene Arctic wood from Ellesmere Island

Science.gov (United States)

Schubert, B.; Jahren, H.; Eberle, J.; Sternberg, L.

2009-12-01

Early Eocene (ca. 53 Ma) fossil assemblages on Ellesmere Island (75 oN paleolatitude), provide rich information about the plant and animal life of the lush polar ecosystems of the time. Fossil wood recovered from Ellesmere Island is abundant and not permineralized; however, morphological features such as growth rings and resin canals have been obliterated by compression. We report on exceptionally high-resolution intra-ring analyses of δ13C within fossil wood, sampled at ~30 micron intervals across several centimeters of wood sample. Clear patterns in systematic seasonal increases and decreases in wood δ13C allowed us to identify at least 5 annual cycles in the wood. The patterns of increase and decrease in δ13C were consistent with patterns observed for evergreen wood, and distinct from the deciduous patterns we have observed for Metasequoia fossil wood from the middle Eocene (ca. 45 Ma) Arctic site on Axel Heiberg Island. We believe that the high point in the δ13C value of wood seen in each cycle corresponds to the highest environmental temperatures during the annual cycle, as has been seen for modern evergreens (e.g., Barbour et al., 2002). Modern studies have also noted that high temperature periods are correlated with the highest vapor-pressure and soil-water deficits of the annual cycle; these environmental factors would cause the plant to change its discrimination during photosynthesis. We will discuss the relatively low amplitude of δ13C fluctuations (0.5-1.0 ‰) clearly defined by Ellesmere fossil wood, in comparison to observations on modern common evergreens (2.0-4.0 ‰), and speculate that this difference implies greatly dampened seasonal temperature fluctuations in Eocene polar environments, relative to today. Barbour M.M., Walcroft A.S., Farquhar G.D., 2002, Seasonal variation in δ13C and δ18O of cellulose from growth rings of Pinus radiata. Plant, Cell and Environment: v. 25, p. 1483-1499.

Still rethinking the value of high wood density.

Science.gov (United States)

Larjavaara, Markku; Muller-Landau, Helene C

2012-01-01

In a previous paper, we questioned the traditional interpretation of the advantages and disadvantages of high wood density (Functional Ecology 24: 701-705). Niklas and Spatz (American Journal of Botany 97: 1587-1594) challenged the biomechanical relevance of studying properties of dry wood, including dry wood density, and stated that we erred in our claims regarding scaling. We first present the full derivation of our previous claims regarding scaling. We then examine how the fresh modulus of rupture and the elastic modulus scale with dry wood density and compare these scaling relationships with those for dry mechanical properties, using almost exactly the same data set analyzed by Niklas and Spatz. The derivation shows that given our assumptions that the modulus of rupture and elastic modulus are both proportional to wood density, the resistance to bending is inversely proportional to wood density and strength is inversely proportional with the square root of wood density, exactly as we previously claimed. The analyses show that the elastic modulus of fresh wood scales proportionally with wood density (exponent 1.05, 95% CI 0.90-1.11) but that the modulus of rupture of fresh wood does not, scaling instead with the 1.25 power of wood density (CI 1.18-1.31). The deviation from proportional scaling for modulus of rupture is so small that our central conclusion remains correct: for a given construction cost, trees with lower wood density have higher strength and higher resistance to bending.

CO2 abatement potential of wood utilisation. Wood as an energy carrier

International Nuclear Information System (INIS)

Wegener, G.; Fruehwald, A.

1994-01-01

Forests as ecosystems not only supply the raw material wood but also exert an influence on soils, water resources and many other ecological factors; provide animals with a habitat; and offer as humans a place for recreation. Recently, forests and wood have become of interest to human civilisation from yet another aspect: they constitute a carbon storage. This means that forestry and the forest industries can help moderate the increase of atmospheric CO 2 concentrations, which is essentially the result of energetic utilisation of fossil fuels and considered the decisive factor underlying the greenhouse effect. Besides constituting a carbon storage, forests hold an additional CO 2 abatement potential which can be realised by continuous utilisation of wood. (orig./EF) [de

Application of polymerization techniques to the treatment of woods gorged with water

Energy Technology Data Exchange (ETDEWEB)

Detanger, B; Ramiere, R; de Tassigny, C; Eymery, R; de Nadaillac, L

1973-05-01

From international conference on application of nuclear data in the field of work of art; Rome-Venice, Italy (24 May 1973). Wooden objects from stagnant or flowing waters have great value for the study of prehistory and protohistory. The preservation of these objects offers great difficulties as the elimination of the water causes them to crack, warp, or sag irreversibly. Ancient water-saturated woods were studied botanically, physicochemically, and biologically in order to develop techniques for their preservation in their original form. The studies showed that the simultaneous use of a technique of liquid-liquid extraction of the water and the polymerization under gamma radiation of the monomer introduced by substitution offers possibilities which merit a more in-depth study. (JSR)

Development of wood decay in wound-initiated discolored wood of eastern red cedar

Science.gov (United States)

Walter C. Shortle; Kenneth R. Dudzik; Kevin T. Smith

2010-01-01

Logs of eastern red cedar, Juniperus virginiana L., with well-developed bands of light-colored wood ("included sapwood") within heartwood can be unsuitable for sawn wood products. This finding is in contrast to published information that the "included sapwood" is (1) a heartwood anomaly rather than sapwood and (2) its occurrence...

The extractives of Pinus pinaster wood

Science.gov (United States)

Richard W. Hemingway; W. E. Hillis; L. S. Lau

1973-01-01

The extractives in Pinus pinaster wood grown in South Australia were examined as part of an assessment of the suitability of this wood for manufacture of absorbent tissues from bisulphite pulps. The average petroleum solubility of the wood was 2.0% but the amount and composition of the petroleum extract varied widely depending upon the age of the...

Wood supply : what bioenergy resources are available as harvest residue and non-merchantable wood in New Brunswick?

International Nuclear Information System (INIS)

Forgrave, K.

2005-01-01

This paper examines resources available for bioenergy production in New Brunswick. An estimate of New Brunswick harvest levels, based on New Brunswick Forest Products Association web site figures was presented. Private wood lots harvest levels were also provided, with all estimates based on volume per year. Market conditions were discussed, with an emphasis on the dictates of price and availability for private wood lot owners. Market conditions and unused volume statistics were discussed. Various forest management options include the use of veneer, saw log, stud wood and pulp wood. Details of bioenergy percentages and potential were presented and general silviculture issues were discussed. It was concluded that many of the trade-offs of bioenergy involve placing more demands on forests, and that purchase prices will increasingly dictate volumes obtained from private wood lots. tabs, figs

Potential recovery of industrial wood and energy wood raw material in different cutting and climate scenarios for Finland

International Nuclear Information System (INIS)

Kaerkkaeinen, Leena; Nuutinen, Tuula; Matala, Juho; Kellomaeki, Seppo; Haerkoenen, Kari

2008-01-01

The aim of this study was to estimate the simultaneous recovery of industrial wood and raw material for energy wood from cuttings in Finland during the next 50 years. Two cutting scenarios (maximum and sustainable cuttings) and two climate scenarios (current and changing climate) were analysed to determine their impacts on harvesting potential. The analysis was carried out using sample plot and tree data from the ninth National Forest Inventory and a management-oriented large-scale forestry model (MELA) into which the transfer functions based on physiological modelling were incorporated to describe the impacts of climate change. Depending on the climate scenario, the volume of potential recovery of industrial wood in the maximum cutting scenario during the period 2003-2013 varied from 103 to 105 million m 3 a -1 , while the amount of potential energy wood raw material was 35 Tg a -1 . During the period 2043-2053, in the current climate scenario, the potential recovery of industrial wood was 64 million m 3 a -1 and energy wood raw material 22 Tg a -1 , and in the changing climate scenario, 85 million m 3 a -1 and 29 Tg a -1 , respectively. In the sustainable cutting scenario, depending on the climate scenario used, the potential recovery of industrial wood during the period 2003-2013 varied from 74 to 76 million m 3 a -1 , while the amount of potential energy wood was 25 Tg a -1 . During the period 2043-2053, in the current climate scenario, the potential recovery of industrial wood was 80 million m 3 a -1 and energy wood raw material 26 Tg a -1 , and in the changing climate scenario, 88 million m 3 a -1 and 29 Tg a -1 , respectively. (author)

Quantifying cambial activity of high-elevation conifers in the Great Basin, Nevada, USA

Science.gov (United States)

Ziaco, E.; Biondi, F.; Rossi, S.; Deslauriers, A.

2013-12-01

Understanding the physiological mechanisms that control the formation of tree rings provides the necessary biological basis for developing dendroclimatic reconstructions and dendroecological histories. Studies of wood formation in the Great Basin are now being conducted in connection with the Nevada Climate-ecohydrological Assessment Network (NevCAN), a recently established transect of valley-to-mountaintop instrumented stations in the Snake and Sheep Ranges of the Great Basin. Automated sensors record meteorological, soil, and vegetational variables at these sites, providing unique opportunities for ecosystem science, and are being used to investigate the ecological implications of xylogenesis. We present here an initial study based on microcores collected during summer 2013 from mountain and subalpine conifers (including Great Basin bristlecone pine, Pinus longaeva) growing on the west slope of Mt. Washington. Samples were taken from the mountain west (SM; 2810 m elevation) and the subalpine west (SS, 3355 m elevation) NevCAN sites on June 16th and 27th, 2013. The SS site was further subdivided in a high (SSH) and a low (SSL) group of trees, separated by about 10 m in elevation. Microscopic analyses showed the effect of elevation on cambial activity, as annual ring formation was more advanced at the lower (mountain) site compared to the higher (subalpine) one. At all sites cambium size showed little variations between the two sampling dates. The number of xylem cells in the radial enlargement phase decreased between the two sampling dates at the mountain site but increased at the subalpine site, confirming a delayed formation of wood at the higher elevations. Despite relatively high within-site variability, a general trend of increasing number of cells in the lignification phase was found at all sites. Mature cells were present only at the mountain site on June 27th. Spatial differences in the xylem formation process emerged at the species level and, within

Wood-based composite materials : panel products, glued-laminated timber, structural composite lumber, and wood-nonwood composite materials

Science.gov (United States)

Nicole M. Stark; Zhiyong Cai; Charles Carll

2010-01-01

This chapter gives an overview of the general types and composition of wood-based composite products and the materials and processes used to manufacture them. It describes conventional wood-based composite panels and structural composite materials intended for general construction, interior use, or both. This chapter also describes wood–nonwood composites. Mechanical...

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.)

Wood waste in Europe

Energy Technology Data Exchange (ETDEWEB)

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

1998-12-31

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.

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.

Environmental assessment of domestic wood heating

International Nuclear Information System (INIS)

Labouze, E.; Le Guerin, Y.

2009-01-01

In France, more than 6 million families are concerned with the domestic use of wood energy. The wood energy plan of ADEME aims at encouraging the development of wood energy in three sectors: domestic, collective/tertiary, industrial. In that context, ADEME commissioned BIO Intelligence Service a life cycle assessment of collective and industrial heating in order to give objective environmental information and to analyse the strength and weakness of wood heating. Three scenarios were defined according to the origin of wood: firewood, granules and sawmill chips. The study also proposes a comparison to other heating systems: gas, fuel oil and electricity. The life cycle analysis applied to domestic heating consists in quantifying the environmental impacts of the whole linked steps: extraction of fuel, distribution, final use... Every system under study has been divided according to three main stages: - Extraction of raw materials; - Transport of fuels until the place of storage or distribution; - Use (combustion or upstream production of energy in the case of electricity). The environmental impacts are estimated with the following indicators: - Non renewable primary energy balance sheet; - Global warming potential; - Air acidification potential; - Eutrophication potential; - Emissions of toxic metals in air and in soils. The results show that wood heating have the best energy and global warming balance sheets. For air acidification, the combustion stage is pre-dominant regardless of the energy resource. This is mainly due to nitrogen and sulphur oxides airborne emissions. For wood heating, preparation requires fuel consumption which also contributes significantly to nitrogen oxides emissions. The comparison with conventional energy shows that the wood scenarios are well positioned in relation to fuel and electricity for this indicator. Gas appears to be the best heating option for this indicator. The contribution eutrophication is also due to nitrogen oxides airborne

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.

Optimising hydrogen bonding in solid wood

DEFF Research Database (Denmark)

Engelund, Emil Tang

2009-01-01

The chemical bonds of wood are both covalent bonds within the wood polymers and hydrogen bonds within and between the polymers. Both types of bonds are responsible for the coherence, strength and stiffness of the material. The hydrogen bonds are more easily modified by changes in load, moisture...... and temperature distorting the internal bonding state. A problem arises when studying hydrogen bonding in wood since matched wood specimens of the same species will have very different internal bonding states. Thus, possible changes in the bonding state due to some applied treatment such as conditioning...... maintaining 100 % moisture content of the wood. The hypothesis was that this would enable a fast stress relaxation as a result of reorganization of bonds, since moisture plasticizes the material and temperature promotes faster kinetics. Hereby, all past bond distortions caused by various moisture, temperature...

Application of Digital Survey Mapping Technology in the Investigation of Colored Wood Statue in the Caoxi Temple

Science.gov (United States)

Li, Y.; Zheng, Y.

2017-08-01

The colored wood statues in the CaoXi Temple represent the Sandashi(Manjushri, Samantabhadra , Avalokitesvar) in the Buddhism.These statues with great value were carved in Dali kingdom of the Song dynasty. Because of natural and man-made reasons, disease has become very seriously both in the painted layer on the surface and the structure inside. So it is very important to record the current situation, analyze the structure, craft and material, and detect the cause of disease. This paper takes the colored wood statues as the research object, and kinds of digital survey technology were applied in the process. The Research results will play an important role in the protection, explanation and display.

Science supporting the economic and environmental benefits of using wood and wood products in green building construction

Science.gov (United States)

Michael A. Ritter; Kenneth Skog; Richard Bergman

2011-01-01

The objective of this report is to summarize the scientific findings that support the environmental and economic benefits of using wood and wood products in green building construction. Despite documented advantages in many peer-reviewed scientific articles, most building professionals and members of the public do not recognize wood as a renewable resource or the role...

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...

How James Wood Works

Science.gov (United States)

Goldstein, Evan R., Comp.

2008-01-01

Reading through news-media clippings about James Wood, one might reasonably conclude that "pre-eminent critic" is his official job title. In fact, Wood is a staff writer for "The New Yorker" and a professor of the practice of literary criticism at Harvard University. But at a time when there is much hand-wringing about the death of the…

Waste-wood resource supply assessment. Final report

International Nuclear Information System (INIS)

1991-08-01

The report documents and analyzes the availability and supply of wood waste in New York State to determine the type and amount currently generated to estimate its potential future use as a fuel. Detailed, current information is included on the availability, quantity and price of wood waste. Topics include wood waste markets; the harvesting and supply infrastructure; current and project prices; competing markets; environmental impacts of harvesting, processing and burning wood waste for fuel; and factors affecting long-term availability and supply. New York State's waste wood resource was evaluated to complete the Energy Authority's recent investigation of the potential role of wood in producing electric power. In 1989 approximately 11.8 million tons of wood waste were generated in New York State. More than 8 million tons or 68 percent, were disposed of by municipal solid waste and construction and demolition debris facilities. Just under 3.8 million tons or 32 percent, were reused and/or recycled. More than 25.7 million tons of wood waste could be available annually for fuel. Of the amount, more than 17.2 million tons per year, or 67 percent, could be produced by silvicultural activities that improve the health and productivity of forests

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.

Southern Woods-Burners: A Descriptive Analysis

Science.gov (United States)

M.L. Doolittle; M.L. Lightsey

1979-01-01

About 40 percent of the South's nearly 60,000 wildfires yearly are set by woods-burners. A survey of 14 problem areas in four southern States found three distinct sets of woods-burners. Most active woods-burners are young, white males whose activities are supported by their peers. An older but less active group have probably retired from active participation but...

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...

Decay resistance of wood-plastic composites reinforced with extracted or delignified wood flour

Science.gov (United States)

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

2014-01-01

The moisture and decay resistance of wood-plastic composites (WPCs) reinforced with extracted or delignified wood flour (WF) was investigated. Three different extractions were preformed: toluene/ethanol (TE), acetone/water (AW), and hot water (HW). Delignification (DL) was performed using a sodium chlorite/acetic acid solution. All WPCs specimens were made with 50% by...

5000 sustainable workplaces - Wood energy provides work

International Nuclear Information System (INIS)

Keel, A.

2009-01-01

This article presents the results of a study made by the Swiss Wood Energy Association on the regional and national added value resulting from large wood-fired installations in Switzerland. The number of workplaces created by these installations is also noted. Wood energy is quoted as not only being a way of using forest wastes but also as being a creator of employment. Large wood-fired heating installations are commented on and efforts to promote this type of energy supply even further are discussed. The study indicates which professions benefit from the use of wood energy and quantifies the number of workplaces per megawatt of installed power that result.

Corrosion of metals in wood : comparing the results of a rapid test method with long-term exposure tests across six wood treatments

Science.gov (United States)

Samuel L. Zelinka; Donald S. Stone

2011-01-01

This paper compares two methods of measuring the corrosion of steel and galvanized steel in wood: a long-term exposure test in solid wood and a rapid test method where fasteners are electrochemically polarized in extracts of wood treated with six different treatments. For traditional wood preservatives, the electrochemical extract method correlates with solid wood...

USE OF CANDEIA’S (Eremanthus erythropappus WASTE WOOD

Directory of Open Access Journals (Sweden)

Rosimeire Cavalcante dos Santos

2008-09-01

Full Text Available The candeia (Eremanthus erythropappus is a native forest species with multiple uses and specially utilized as essential oils source. The use of the candeia´s waste wood after oil extraction for particle panels production becomes a viable alternative, avoiding environmental problems and increasing the availability of these products in the consuming market. This work verified the viability of producing wood-cement panels using waste wood generated after the extraction of candeia’s oil, in association with pinus and eucalipto woods. The experiment was installed according to a completely randomized design with three repetitions. The treatments were arranged according to a factorial 2 x 3 scheme (two wooden species and three replacement percentages of the woods by candeia’s waste. The results of the physical and mechanical property tests showed high potentiality of candeia waste wood, after oil extraction, in association with pinus and eucalipto wood for manufacturing wood-cement panels.

Wood energy barometer. 43 million toe produced in 2003

International Nuclear Information System (INIS)

Anon.

2004-01-01

The use of wood in the form of energy contributes in fighting global warming since, unlike fossil energies, the carbon dioxide emitted by its combustion is reabsorbed by the forests. These environmental and energetic advantages explain why the European Union large wood countries are preparing programmes to develop both wood energy technologies and wood energy consumption; This document takes stock or gives information on the breakdown of valorization of wood energy origin primary energy, the gross electricity generation from wood energy in the 15 european union countries and Poland, the primary energy from wood energy, the comparative between different wood energy fuel prices in Europe, the number of direct and indirect job created in different sectors, the wood energy sector industrialists and a comparison between current trend and white paper objectives. (A.L.B.)

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.

Certification of forests and wood products in Serbia in the context of new European union legislations: Current situation, problems and challenges

Directory of Open Access Journals (Sweden)

Vasiljević Aleksandar

2011-01-01

Full Text Available The paper presents research results of the current situation in the area of certification of forests and wood products in Serbia in the context of new European Union legislation referring to the placement of wood and wood products on this market. The objective of the research was to observe the situation, phases which Serbia implemented in the process of forest and wood products certification until now, as well as the problems and challenges the companies in this process face. Based on research results, future development of the market of certified wood products in Serbia was assessed and the proposal of measures which should be realized in order for Serbia to become a country whose companies will be ready for the moment when provisions and measures of the new EU legislation become effective was given. The selection of the abovementioned objective was conditioned by the fact that from January 1st, 2013 new legislation takes effect, with significantly stricter terms for the placement of wood and wood products from other countries on this market. One of the conditions which will have to be fulfilled by the companies wishing to export their products on this market refers to proving their origin. Since the EU is the most significant market for wood products exported from Serbia, fulfillment of the stated and other terms from the new EU legislation is of great importance to Serbian companies. Until the beginning of September 2010, only 387,000 ha were certified, namely 17.2% of the total area under forests. In the same period, only 33 wood processing companies in Serbia possessed CoC certificates for their products. Such a small number of companies possessing certificates for their wood products compared to competitive neighboring countries can represent a serious limitation in achieving their satisfactory competitiveness on the EU market in the following period.

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.

Wood decomposition as influenced by invertebrates.

Science.gov (United States)

Ulyshen, Michael D

2016-02-01

The diversity and habitat requirements of invertebrates associated with dead wood have been the subjects of hundreds of studies in recent years but we still know very little about the ecological or economic importance of these organisms. The purpose of this review is to examine whether, how and to what extent invertebrates affect wood decomposition in terrestrial ecosystems. Three broad conclusions can be reached from the available literature. First, wood decomposition is largely driven by microbial activity but invertebrates also play a significant role in both temperate and tropical environments. Primary mechanisms include enzymatic digestion (involving both endogenous enzymes and those produced by endo- and ectosymbionts), substrate alteration (tunnelling and fragmentation), biotic interactions and nitrogen fertilization (i.e. promoting nitrogen fixation by endosymbiotic and free-living bacteria). Second, the effects of individual invertebrate taxa or functional groups can be accelerative or inhibitory but the cumulative effect of the entire community is generally to accelerate wood decomposition, at least during the early stages of the process (most studies are limited to the first 2-3 years). Although methodological differences and design limitations preclude meta-analysis, studies aimed at quantifying the contributions of invertebrates to wood decomposition commonly attribute 10-20% of wood loss to these organisms. Finally, some taxa appear to be particularly influential with respect to promoting wood decomposition. These include large wood-boring beetles (Coleoptera) and termites (Termitoidae), especially fungus-farming macrotermitines. The presence or absence of these species may be more consequential than species richness and the influence of invertebrates is likely to vary biogeographically. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

Wood Programs. Courseware Evaluation for Vocational and Technical Education.

Science.gov (United States)

Kaylor, Robert; And Others

This courseware evaluation rates the Wood Programs software developed by the Iowa Department of Public Instruction. (These programs--not contained in this document--include understanding board feet, wood characteristics, wood safety drill, wood dimensions, wood moisture, operating the table saw, radial arm, measurement drill, fraction drill, and…

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.

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....... This book examines the diverse expressions of wood-pastures across Europe. It provides a new perspective, using a social-ecological framework to explore social and ecological values, governing institutions, threats and conservation approaches. It explores the major drivers of decline, which are shown...

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.

Properties of wood-plastic composites (WPCs) 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

The water sorption and mechanical properties of wood-plastic composites (WPCs) made of extracted and delignified wood flour (WF) has been investigated. WF was prepared by extraction with the solvent systems toluene/ethanol (TE), acetone/water (AW), and hot water (HW), and its delignification was conducted by means of sodium chlorite/acetic acid (AA) solution. A 2 4...

Hydrothermal Synthesis of Nanooctahedra MnFe₂O₄ onto the Wood Surface with Soft Magnetism, Fire Resistance and Electromagnetic Wave Absorption.

Science.gov (United States)

Wang, Hanwei; Yao, Qiufang; Wang, Chao; Ma, Zhongqing; Sun, Qingfeng; Fan, Bitao; Jin, Chunde; Chen, Yipeng

2017-05-23

In this study, nanooctahedra MnFe₂O₄ were successfully deposited on a wood surface via a low hydrothermal treatment by hydrogen bonding interactions. As-prepared MnFe₂O₄/wood composite (MW) had superior performance of soft magnetism, fire resistance and electromagnetic wave absorption. Among them, small hysteresis loops and low coercivity (magnetization-field curve of MW with saturation magnetization of 28.24 emu/g, indicating its excellent soft magnetism. The MW also exhibited a good fire-resistant property due to its initial burning time at 20 s; while only 6 s for the untreated wood (UW) in combustion experiments. Additionally, this composite revealed good electromagnetic wave absorption with a minimum reflection loss of -9.3 dB at 16.48 GHz. Therefore, the MW has great potential in the fields of special decoration and indoor electromagnetic wave absorbers.

Potential of Reinforced Indonesian Glulam Beams Using Grade I (Bengkirai, Grade II (Kamper, Grade III (Nyatoh Woods for Use in Structural Wood Design

Directory of Open Access Journals (Sweden)

Saptahari Sugiri

2016-05-01

Full Text Available Wood is a natural resource that is renewable and available in various species in tropical countries. Its abundancy in nature makes it easy to obtain, thus making it a nature friendly material for use in construction. Indonesia is the most important source of tropical wood in the world after Brazil, making the use of wood for structural elements very desirable. It is estimated that 4000 different varieties of wood exist in Indonesia. This estimate is based on the herbarium species collected by the Forestry Research Institute, currently counting nearly 4000 types of trees with a diameter of more than 40 cm. In the Indonesian wood structure code, the strength of woods is divided into 3 grades (grade I, II and III. This paper presents an evaluation of the mechanical properties of glulam wood sourced from native Indonesian timber: Bengkirai wood (grade I, Kamper wood (grade II, and Nyatoh wood (grade III, thus proving the potential for Indonesian wood as industrial structural elements in wooden constructions.

Wood energy in Switzerland - fillet steaks and sausages

International Nuclear Information System (INIS)

Keel, A.

2004-01-01

This article discusses the increasing use of wood energy to help meet Switzerland's energy needs. The increasing interest in wood-fired systems in comparison with fossil fuels is commented on. The article presents figures on energy carriers and the shares of the energy supply they meet as well as the development of wood-fired systems between 1991 and 2003. The influence of Swiss regional identities on the market for wood heating systems is discussed, as are difficulties resulting from stop-and-go governmental promotional funding. The importance of wood-fired energy systems for local authorities with difficulties in selling wood from their communal forestry departments is also discussed

Forest biomass and wood waste resources

Science.gov (United States)

K. Skog; P. Lebow; D.. Dykstra; P.. Miles; B.J. Stokes; R.D. Perlack; M. Buford; J. Barbour; D. McKeever

2011-01-01

This chapter provides estimates of forest biomass and wood waste quantities, as well as roadside costs (i.e., supply curves) for each county in the contiguous United States. Roadside price is the price a buyer pays for wood chips at a roadside in the forest, at a processing mill location in the case of mill residue, or at a landfill for urban wood wastes prior to any...

Soil quality in a cropland soil treated with wood ash containing charcoal

Science.gov (United States)

Omil, Beatriz; Balboa, Miguel A.; Fonturbel, M. Teresa; Gartzia-Bengoetxea, Nahia; Arias-González, Ander; Vega, Jose A.; Merino, Agustin

2014-05-01

. Three years after applications the SOM content increased lightly in the treatment receiving more than 16 Mg ha-1 of wood ash. SOM in the treated soils displayed a higher degree of aromaticity than in the untreated soils, indicating a gain in more stable SOM compounds probably as a consequence of the charcoal application. However, both methods also revealed increases in labile C compounds, probably due to the carbohydrates added through root system. Microbial biomass-C and soil respiration increased significantly. The treatments also led to increases in the functional diversity indices. The amended soils showed greater utilization of substrates and the ability of soil bacteria to utilize different C resources was also greatly altered. The application of mixed wood ash did not lead to any difference in MWD, which was around 6 mm in all cases. The application of 16 Mg fly wood ash ha-1 increased significantly the hydraulic conductivity (4.07 cmh-1) when compared with in control plots (1.3 cmh-1) and mixed ash plots (1.52 and 2.45 cmh-1, 16 Mg and 32 Mg respectively). However, air-filled porosity was not higher in 16 Mg fly ash plots. AWC was not improved by wood ash application.

Selected mechanical properties of modified beech wood

Directory of Open Access Journals (Sweden)

Jiří Holan

2008-01-01

Full Text Available This thesis deals with an examination of mechanical properties of ammonia treated beach wood with a trademark Lignamon. For determination mechanical properties were used procedures especially based on ČSN. From the results is noticeable increased density of wood by 22% in comparison with untreated beach wood, which makes considerable increase of the most mechanical wood properties. Considering failure strength was raised by 32% and modulus of elasticity was raised at average about 46%.

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.)

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...

Chemical modification of wood

Science.gov (United States)

Roger M. Rowell

2007-01-01

After millions of years of evolution, wood was designed to perform in a wet environment, and nature is programmed to recycle it, in a timely way, back to the basic building blocks of carbon dioxide and water through biological, thermal, aqueous, photochemical, chemical, and mechanical degradation. The properties of wood are, for the most part, a result of the chemistry...

Physico-mechanical properties of Spanish juniper wood considering the effect of heartwood formation and the presence of defects and imperfections

Directory of Open Access Journals (Sweden)

Javier de la Fuente-Leon

2014-04-01

Full Text Available Aim of study: Determining the main physical and mechanical properties of Spanish juniper wood from Soria (Spain considering the effects of heartwood formation and the presence of defects and imperfections; and comparing the resulting characteristics with similar existing data for other regional softwood species of commercial interest. Area of study: Berlanga de Duero (Soria, Castilla y León, Spain.Material and Methods: Wood physico-mechanical performance was determined by Spanish UNE standards in order to provide proper comparisons to other regional softwood species. An individual tree representing average plot characteristics was selected in all eight 10 m radius circular plots that were established well-representing the heterogeneity of this woodland. The age of every tree was determined reading the number of growth rings at the base of each sampled tree. Every physico-mechanical property was assessed at least 4 times for every wood sample type (sapwood and heartwood, whether clear or with the presence of defects of each tree. Two-way ANOVA was run to assess significant differences in the results. Post hoc all pairwise comparisons were performed using Tukey's test (p < 0.05.Research highlights: Spanish juniper wood resulted harder than other regional commercial conifers, and showed semi-heavyweight heartwood and lightweight sapwood; whereas shrinkage figures remarked its great dimensional stability. The high presence of knots within heartwood made it even heavier, harder, and more resistant to compression parallel to grain. A commercial use of this rare precious wood may contribute to juniper forests preservation in the frame of forest sustainable management plans. Key words: heartwood effect; Juniperus thurifera L.; physico-mechanical wood properties; wood classification; wood defects.

A geographical analysis of the Swedish wood fuel market

International Nuclear Information System (INIS)

Roos, Anders; Bohlin, Folke; Hektor, Bo; Hillring, Bengt; Parikka, Matti

2000-01-01

The geographical variation in Swedish wood fuel market characteristics for the district heating sector has been studied using Geographical Information Systems (GIS) and cross-sectional Tobit analysis. The results indicate that local availability and competition for wood fuels influence the wood fuel consumption at inland heating plants. The factors affecting the decision to use wood fuel at heating plants close to seaports, however, were not captured by the model, suggesting that coastal location reduces dependency on the local wood fuel market. The effects of changes in local wood fuel availability on wood fuel use by an inland heating plant are presented and discussed

Construction of Hydrophobic Wood Surface and Mechanical Property of Wood Cell Wall on Nanoscale Modified by Dimethyldichlorosilane

Science.gov (United States)

Yang, Rui; Wang, Siqun; Zhou, Dingguo; Zhang, Jie; Lan, Ping; Jia, Chong

2018-01-01

Dimethyldichlorosilane was used to improve the hydrophobicity of wood surface. The water contact angle of the treated wood surface increased from 85° to 143°, which indicated increased hydrophobicity. The nanomechanical properties of the wood cell wall were evaluated using a nanoindentation test to analyse the hydrophobic mechanism on the nano scale. The elastic modulus of the cell wall was significantly affected by the concentration but the influence of treatment time is insignificant. The hardness of the cell wall for treated samples was significantly affected by both treatment time and concentration. The interaction between treatment time and concentration was extremely significant for the elastic modulus of the wood cell wall.

Wood pellets for stoker burner

International Nuclear Information System (INIS)

Nykaenen, S.

2000-01-01

The author of this article has had a stoker for several years. Wood chips and sod peat has been used as fuels in the stoker, either separately or mixed. Last winter there occurred problems with the sod peat due to poor quality. Wood pellets, delivered by Vapo Oy were tested in the stoker. The price of the pellets seemed to be a little high 400 FIM/500 kg large sack. If the sack is returned in good condition 50 FIM deposit will be repaid to the customer. However, Vapo Oy informed that the calorific value of wood pellets is three times higher than that of sod peat so it should not be more expensive than sod peat. When testing the wood pellets in the stoker, the silo of the stoker was filled with wood pellets. The adjustments were first left to position used for sod peat. However, after the fire had ignited well, the adjustments had to be decreased. The content of the silo was combusted totally. The combustion of the content of the 400 litter silo took 4 days and 22 hours. Respectively combustion of 400 l silo of good quality sod peat took 2 days. The water temperature with wood pellets remained at 80 deg C, while with sod peat it dropped to 70 deg C. The main disadvantage of peat with small loads is the unhomogenous composition of the peat. The results of this test showed that wood pellets will give better efficiency than peat, especially when using small burner heads. The utilization of them is easier, and the amount of ash formed in combustion is significantly smaller than with peat. Wood pellets are always homogenous and dry if you do not spoil it with unproper storage. Pellets do not require large storages, the storage volume needed being less than a half of the volume needed for sod peat. When using large sacks the amount needed can even be transported at the trunk of a passenger car. Depending on the area to be heated, a large sack is sufficient for heating for 2-3 weeks. Filling of stoker every 2-5 day is not an enormous task

Water repellents and water-repellent preservatives for wood

Science.gov (United States)

R. Sam. Williams; William C. Feist

1999-01-01

Water repellents and water-repellent preservatives increase the durability of wood by enabling the wood to repel liquid water. This report focuses on water-repellent finishes for wood exposed outdoors above ground. The report includes a discussion of the effects of outdoor exposure on wood, the characteristics of water repellent and water-repellent preservative...

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.

Ethanol from wood 'can be competitive'

Energy Technology Data Exchange (ETDEWEB)

1981-06-19

Estimates by Stones and Webster indicate that the cost of producing ethanol for fuel purposes from wood will be as cheap as any other method and comparable with proven sugarcane and maize technology. In coming to this conclusion, it was assumed that significant advances would be made in the hydrolysis of wood and that saleable by-products would be possible from the lignin and hemicellulose of the feedstock wood.

Rural Fuel-wood and Poles Research Project in Malawi: a general account

Energy Technology Data Exchange (ETDEWEB)

Nkaonja, R S.W.

1981-01-01

The Rural Fuel-wood and Poles Research Project was initiated to provide information about afforestation in the dry silvicultural zones. Plantation forestry in Malawi has concentrated on production of timber, poles, and pulpwood. It is estimated that 90% of Malawi's population of 5.5 million live in rural communities, and that the purely domestic wood requirement is 4.05 cubic m per family (of five) annually. In addition, wood is required for agricultural purposes such as tobacco curing. The remaining indigenous forest cannot meet the demand. There is an urgent need for plantations. Rather than simply planting trees, the aim is to make local communities self-sufficient in forest products. In view of the shortage of land, great emphasis is placed on trying species which have many end-uses-- e.g., poles, fuel-wood, mulch, fodder, and shade--and those which can be grown together with farm crops, a concept known as ''agroforestry.'' Over 20 ha of trials were established at locations in the three regions of the country. Acacia albida allows maize and other farm crops to grow under it, provides good shade and fodder, and--as legume--enriches the soil with nitrogen. Eucalypts were included because most produce straight poles for construction, are drought-hardy, and are rated higher than Gmelina arborea in calorific value, durability, and strength. Another tree favored for its multiple uses is Leucaena leucocephala (Hawaiian giant), but it appears that there is considerable mixture of varieties in the seeds. With the exception of one trial at Bwanje, trials have not included farm crops, but the agroforestry element will be a very important consideration in future trials.

Bio-energy in the wood processing industry. Manual for energy production from residual matter for the wood processing industry

International Nuclear Information System (INIS)

Van Halen, C.J.G.; Arninkhof, M.J.C.; Rommens, P.J.M.; Karsch, P.

2000-04-01

This manual is published within the framework of a project, financed by Novem (EWAB programme) and the European Commission (Altener programme). Similar manuals were drafted in Germany, England and Sweden. The basis of the project was the manual 'Quality manual for small-scale wood incineration and wood gasification', published by Novem in 1998. That quality manual was drafted on the basis of an evaluation of a number of wood combustion and wood gasification projects. The original manual has been improved as a result of comments made by experts in the field of bio-energy. Updated information was added with respect to legislation, financing options and new technology. Also the manual is focused more on the wood processing industry

Selection and application of exterior stains for wood

Science.gov (United States)

R. Sam. Williams; William C. Feist

1999-01-01

Exterior stains for wood protect the wood surface from sunlight and moisture. Because stains are formulated to penetrate the wood surface, they are not prone to crack or peel as can film-forming finishes, such as paints. This publication describes the properties of stains and wood, methods for applying stains, and the expected service life of stains.

Housing and the wood industry, trends & market conditions

Science.gov (United States)

Urs Buehlmann; Matt Bumgardner; Al Schuler; K. Koenig

2011-01-01

Housing markets continue to have major impacts on the secondary wood industry. So, what are the steps being taken by wood products manufacturers in order to stay viable? As a follow-up to last year's article, "Housing Market's Impact on the Secondary Woodworking Industry" (Wood & Wood Products, July 2010), the focus of this year's study was...

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

Waste wood as bioenergy feedstock. Climate change impacts and related emission uncertainties from waste wood based energy systems in the UK.

Science.gov (United States)

Röder, Mirjam; Thornley, Patricia

2018-04-01

Considering the urgent need to shift to low carbon energy carriers, waste wood resources could provide an alternative energy feedstock and at the same time reduce emissions from landfill. This research examines the climate change impacts and related emission uncertainties of waste wood based energy. For this, different grades of waste wood and energy application have been investigated using lifecycle assessment. Sensitivity analysis has then been applied for supply chain processes and feedstock properties for the main emission contributing categories: transport, processing, pelletizing, urea resin fraction and related N 2 O formation. The results show, depending on the waste wood grade, the conversion option, scale and the related reference case, that emission reductions of up to 91% are possible for non-treated wood waste. Compared to this, energy from treated wood waste with low contamination can achieve up to 83% emission savings, similar to untreated waste wood pellets, but in some cases emissions from waste wood based energy can exceed the ones of the fossil fuel reference - in the worst case by 126%. Emission reductions from highly contaminated feedstocks are largest when replacing electricity from large-scale coal and landfill. The highest emission uncertainties are related to the wood's resin fraction and N 2 O formation during combustion and, pelletizing. Comparing wood processing with diesel and electricity powered equipment also generated high variations in the results, while emission variations related to transport are relatively small. Using treated waste wood as a bioenergy feedstock can be a valid option to reduce emissions from energy production but this is only realisable if coal and landfill gas are replaced. To achieve meaningful emission reduction in line with national and international climate change targets, pre-treatment of waste wood would be required to reduce components that form N 2 O during the energy conversion. Copyright © 2017

Brazilian sawn wood price and income elasticity

Directory of Open Access Journals (Sweden)

Rommel Noce

2010-09-01

Full Text Available This study estimated the sawn wood demand price and income elasticity. Specifically it was estimated the priceelasticity of sawn wood, the cross price elasticity of wood panels and the income elasticity of Brazilian GDP. A log-log model withcorrection through outline of the mobile average (MA(1 was used, adjusted for the period of 1971 to 2006, which showed to bestable, with satisfactory significance levels. It was observed that sawn wood demand is inelastic in relation to price and elastic inrelation to income.

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)

Protection of Wood from Microorganisms by Laccase-Catalyzed Iodination

Science.gov (United States)

Engel, J.; Thöny-Meyer, L.; Schwarze, F. W. M. R.; Ihssen, J.

2012-01-01

In the present work, Norway spruce wood (Picea abies L.) was reacted with a commercial Trametes versicolor laccase in the presence of potassium iodide salt or the phenolic compounds thymol and isoeugenol to impart an antimicrobial property to the wood surface. In order to assess the efficacy of the wood treatment, a leaching of the iodinated and polymerized wood and two biotests including bacteria, a yeast, blue stain fungi, and wood decay fungi were performed. After laccase-catalyzed oxidation of the phenols, the antimicrobial effect was significantly reduced. In contrast, the enzymatic oxidation of iodide (I−) to iodine (I2) in the presence of wood led to an enhanced resistance of the wood surface against all microorganisms, even after exposure to leaching. The efficiency of the enzymatic wood iodination was comparable to that of a chemical wood preservative, VP 7/260a. The modification of the lignocellulose by the laccase-catalyzed iodination was assessed by the Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) technique. The intensities of the selected lignin-associated bands and carbohydrate reference bands were analyzed, and the results indicated a structural change in the lignin matrix. The results suggest that the laccase-catalyzed iodination of the wood surface presents an efficient and ecofriendly method for wood protection. PMID:22865075

CCA-treated wood disposed in landfills and life-cycle trade-offs with waste-to-energy and MSW landfill disposal.

Science.gov (United States)

Jambeck, Jenna; Weitz, Keith; Solo-Gabriele, Helena; Townsend, Timothy; Thorneloe, Susan

2007-01-01

Chromated copper arsenate (CCA)-treated wood is a preservative treated wood construction product that grew in use in the 1970s for both residential and industrial applications. Although some countries have banned the use of the product for some applications, others have not, and the product continues to enter the waste stream from construction, demolition and remodeling projects. CCA-treated wood as a solid waste is managed in various ways throughout the world. In the US, CCA-treated wood is disposed primarily within landfills; however some of the wood is combusted in waste-to-energy (WTE) facilities. In other countries, the predominant disposal option for wood, sometimes including CCA-treated wood, is combustion for the production of energy. This paper presents an estimate of the quantity of CCA-treated wood entering the disposal stream in the US, as well as an examination of the trade-offs between landfilling and WTE combustion of CCA-treated wood through a life-cycle assessment and decision support tool (MSW DST). Based upon production statistics, the estimated life span and the phaseout of CCA-treated wood, recent disposal projections estimate the peak US disposal rate to occur in 2008, at 9.7 million m(3). CCA-treated wood, when disposed with construction and demolition (C&D) debris and municipal solid waste (MSW), has been found to increase arsenic and chromium concentrations in leachate. For this reason, and because MSW landfills are lined, MSW landfills have been recommended as a preferred disposal option over unlined C&D debris landfills. Between landfilling and WTE for the same mass of CCA-treated wood, WTE is more expensive (nearly twice the cost), but when operated in accordance with US Environmental Protection Agency (US EPA) regulations, it produces energy and does not emit fossil carbon emissions. If the wood is managed via WTE, less landfill area is required, which could be an influential trade-off in some countries. Although metals are concentrated

Genetic dissection of growth, wood basic density and gene expression in interspecific backcrosses of Eucalyptus grandis and E. urophylla

Science.gov (United States)

2012-01-01

Background F1 hybrid clones of Eucalyptus grandis and E. urophylla are widely grown for pulp and paper production in tropical and subtropical regions. Volume growth and wood quality are priority objectives in Eucalyptus tree improvement. The molecular basis of quantitative variation and trait expression in eucalypt hybrids, however, remains largely unknown. The recent availability of a draft genome sequence (http://www.phytozome.net) and genome-wide genotyping platforms, combined with high levels of genetic variation and high linkage disequilibrium in hybrid crosses, greatly facilitate the detection of quantitative trait loci (QTLs) as well as underlying candidate genes for growth and wood property traits. In this study, we used Diversity Arrays Technology markers to assess the genetic architecture of volume growth (diameter at breast height, DBH) and wood basic density in four-year-old progeny of an interspecific backcross pedigree of E. grandis and E. urophylla. In addition, we used Illumina RNA-Seq expression profiling in the E. urophylla backcross family to identify cis- and trans-acting polymorphisms (eQTLs) affecting transcript abundance of genes underlying QTLs for wood basic density. Results A total of five QTLs for DBH and 12 for wood basic density were identified in the two backcross families. Individual QTLs for DBH and wood basic density explained 3.1 to 12.2% of phenotypic variation. Candidate genes underlying QTLs for wood basic density on linkage groups 8 and 9 were found to share trans-acting eQTLs located on linkage groups 4 and 10, which in turn coincided with QTLs for wood basic density suggesting that these QTLs represent segregating components of an underlying transcriptional network. Conclusion This is the first demonstration of the use of next-generation expression profiling to quantify transcript abundance in a segregating tree population and identify candidate genes potentially affecting wood property variation. The QTLs identified in this

Fast enhancement on hydrophobicity of poplar wood surface using low-pressure dielectric barrier discharges (DBD) plasma

Energy Technology Data Exchange (ETDEWEB)

Chen, Weimin [College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037 (China); Jiangsu Engineering Research Center of Fast-growing Trees and Agri-fiber Materials, Nanjing 210037 (China); Nanjing Suman Plasma Technology Co., Ltd, Enterprise of Graduate Research Station of Jiangsu Province, No. 3 Youyihe Road, Nanjing 210001 (China); Zhou, Xiaoyan, E-mail: zhouxiaoyan@njfu.edu.cn [College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037 (China); Jiangsu Engineering Research Center of Fast-growing Trees and Agri-fiber Materials, Nanjing 210037 (China); Zhang, Xiaotao [College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037 (China); Jiangsu Engineering Research Center of Fast-growing Trees and Agri-fiber Materials, Nanjing 210037 (China); Bian, Jie [Nanjing Suman Plasma Technology Co., Ltd, Enterprise of Graduate Research Station of Jiangsu Province, No. 3 Youyihe Road, Nanjing 210001 (China); Shi, Shukai; Nguyen, Thiphuong; Chen, Minzhi [College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037 (China); Jiangsu Engineering Research Center of Fast-growing Trees and Agri-fiber Materials, Nanjing 210037 (China); Wan, Jinglin [Nanjing Suman Plasma Technology Co., Ltd, Enterprise of Graduate Research Station of Jiangsu Province, No. 3 Youyihe Road, Nanjing 210001 (China)

2017-06-15

Highlights: • Plasma working under low pressure is easy to realize industrialization. • Enhancing process finished within 75 s. • Plasma treatment leads to the increase in equilibrium contact angle by 330%. • Tinfoil film with simple chemical structure was used to reveal the mechanism. - Abstract: The hydrophilicity of woody products leads to deformation and cracks, which greatly limits its applications. Low-pressure dielectric barrier discharge (DBD) plasma using hexamethyldisiloxane was applied in poplar wood surface to enhance the hydrophobicity. The chemical properties, micro-morphology, and contact angles of poplar wood surface before and after plasma treatment were investigated by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), x-ray photoelectron spectroscopy (XPS), scanning electron microscope and energy dispersive analysis of X-ray (SEM-EDX), atomic force microscopy (AFM), and optical contact angle measurement (OCA). Moreover, tinfoil film was used as the base to reveal the enhancement mechanism. The results showed that hexamethyldisiloxane monomer is first broken into several fragments with active sites and hydrophobic chemical groups. Meanwhile, plasma treatment results in the formation of free radicals and active sites in the poplar wood surface. Then, the fragments are reacted with free radicals and incorporated into the active sites to form a network structure based on the linkages of Si-O-Si and Si−O−C. Plasma treatment also leads to the formation of acicular nano-structure in poplar wood surface. These facts synergistically enhance the hydrophobicity of poplar wood surface, demonstrating the dramatically increase in the equilibrium contact angle by 330%.

Common wood decay fungi found in the Caribbean Basin

Science.gov (United States)

D. Jean. Lodge

2016-01-01

There are hundreds of wood-decay fungi in the Caribbean Basin, but relatively few of these are likely to grow on manmade structures built of wood or wood-composites. The wood-decay fungi of greatest concern are those that cause brown-rot, and especially brown-rot fungi that are resistant to copper-based wood preservatives. Some fungi that grow in the Caribbean and...

Wood construction codes issues in the United States

Science.gov (United States)

Douglas R. Rammer

2006-01-01

The current wood construction codes find their origin in the 1935 Wood Handbook: Wood as an Engineering Material published by the USDA Forest Service. Many of the current design recommendations can be traced back to statements from this book. Since this time a series of development both historical and recent has led to a multi-layered system for use of wood products in...

29 CFR 1910.25 - Portable wood ladders.

Science.gov (United States)

2010-07-01

... for the construction, care, and use of the common types of portable wood ladders, in order to insure... density wood shall not be used. (ii) [Reserved] (2) [Reserved] (c) Construction requirements. (1... 29 Labor 5 2010-07-01 2010-07-01 false Portable wood ladders. 1910.25 Section 1910.25 Labor...

21 CFR 178.3800 - Preservatives for wood.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Preservatives for wood. 178.3800 Section 178.3800... Certain Adjuvants and Production Aids § 178.3800 Preservatives for wood. Preservatives may be safely used... to accomplish the technical effect of protecting the wood from decay, mildew, and water absorption...

30 CFR 77.1913 - Fire-resistant wood.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fire-resistant wood. 77.1913 Section 77.1913 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH... Shaft Sinking § 77.1913 Fire-resistant wood. Except for crossties, timbers, and other wood products...

Wood-hoopoes: are Phoeniculus purpureus niloticus (Neumann ...

African Journals Online (AJOL)

The Green Wood-hoopoe Phoeniculus purpureus (Miller 1784) is represented in all savanna regions of Africa, and has long been the subject of debate (Turner 2014). In addition, birds referred to as the Violet Wood-hoopoe (damarensis and granti) and. Black-billed Wood-hoopoe (somaliensis) appear very closely related to ...

Okanagan indoor wood burning appliance inventory survey

International Nuclear Information System (INIS)

2001-01-01

A survey was conducted to determine the usage and nature of wood burning appliances used by residents in British Columbia's Okanagan region. The objective was to better understand this source of air quality concern and to facilitate strategic planning, guidelines and legislation. The survey also provides a baseline to track the effectiveness of any reduction strategies. It identifies the different types of wood burning appliances used in the community and presents residential options about potential bylaws to protect air quality. The receptivity of households to switch to more efficient wood burning appliances was also examined. The survey completes a portion of an overall emissions inventory for the Okanagan Valley. Environment Canada uses the particulate loading results to model the air quality in the airshed. Results showed that approximately 21 per cent of the households in the Okanagan use indoor wood burning appliances, and burn an average of 2.3 cords of wood each year. Only 11 per cent of the appliances are considered to have advanced burning technology. It is projected that the use of wood burning appliances in the Okanagan will increase by 5 to 7 per cent in the next 2 years. Most residents have good burning habits, but some improvements can still be made. Many residents are considering exchanging old wood burning appliances for clean burning technology appliances for environmental and health reasons. Most households would support a bylaw to control nuisance amounts of smoke from wood burning appliances. 20 tabs., 5 figs

Wood phenology, not carbon input, controls the interannual variability of wood growth in a temperate oak forest.

Science.gov (United States)

Delpierre, Nicolas; Berveiller, Daniel; Granda, Elena; Dufrêne, Eric

2016-04-01

Although the analysis of flux data has increased our understanding of the interannual variability of carbon inputs into forest ecosystems, we still know little about the determinants of wood growth. Here, we aimed to identify which drivers control the interannual variability of wood growth in a mesic temperate deciduous forest. We analysed a 9-yr time series of carbon fluxes and aboveground wood growth (AWG), reconstructed at a weekly time-scale through the combination of dendrometer and wood density data. Carbon inputs and AWG anomalies appeared to be uncorrelated from the seasonal to interannual scales. More than 90% of the interannual variability of AWG was explained by a combination of the growth intensity during a first 'critical period' of the wood growing season, occurring close to the seasonal maximum, and the timing of the first summer growth halt. Both atmospheric and soil water stress exerted a strong control on the interannual variability of AWG at the study site, despite its mesic conditions, whilst not affecting carbon inputs. Carbon sink activity, not carbon inputs, determined the interannual variations in wood growth at the study site. Our results provide a functional understanding of the dependence of radial growth on precipitation observed in dendrological studies. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Spatio-temporal variability of ichthyophagous bird assemblage around western Mediterranean open-sea cage fish farms.

Science.gov (United States)

Aguado-Giménez, Felipe; Eguía-Martínez, Sergio; Cerezo-Valverde, Jesús; García-García, Benjamín

2018-06-14

Ichthyophagous birds aggregate at cage fish farms attracted by caged and associated wild fish. Spatio-temporal variability of such birds was studied for a year through seasonal visual counts at eight farms in the western Mediterranean. Correlation with farm and location descriptors was assessed. Considerable spatio-temporal variability in fish-eating bird density and assemblage structure was observed among farms and seasons. Bird density increased from autumn to winter, with the great cormorant being the most abundant species, also accounting largely for differences among farms. Grey heron and little egret were also numerous at certain farms during the coldest seasons. Cattle egret was only observed at one farm. No shags were observed during winter. During spring and summer, bird density decreased markedly and only shags and little egrets were observed at only a few farms. Season and distance from farms to bird breeding/wintering grounds helped to explain some of the spatio-temporal variability. Copyright © 2018 Elsevier Ltd. All rights reserved.

How deep-sea wood falls sustain chemosynthetic life.

Directory of Open Access Journals (Sweden)

Christina Bienhold

Full Text Available Large organic food falls to the deep sea--such as whale carcasses and wood logs--are known to serve as stepping stones for the dispersal of highly adapted chemosynthetic organisms inhabiting hot vents and cold seeps. Here we investigated the biogeochemical and microbiological processes leading to the development of sulfidic niches by deploying wood colonization experiments at a depth of 1690 m in the Eastern Mediterranean for one year. Wood-boring bivalves of the genus Xylophaga played a key role in the degradation of the wood logs, facilitating the development of anoxic zones and anaerobic microbial processes such as sulfate reduction. Fauna and bacteria associated with the wood included types reported from other deep-sea habitats including chemosynthetic ecosystems, confirming the potential role of large organic food falls as biodiversity hot spots and stepping stones for vent and seep communities. Specific bacterial communities developed on and around the wood falls within one year and were distinct from freshly submerged wood and background sediments. These included sulfate-reducing and cellulolytic bacterial taxa, which are likely to play an important role in the utilization of wood by chemosynthetic life and other deep-sea animals.

How Deep-Sea Wood Falls Sustain Chemosynthetic Life

Science.gov (United States)

Bienhold, Christina; Pop Ristova, Petra; Wenzhöfer, Frank; Dittmar, Thorsten; Boetius, Antje

2013-01-01

Large organic food falls to the deep sea – such as whale carcasses and wood logs – are known to serve as stepping stones for the dispersal of highly adapted chemosynthetic organisms inhabiting hot vents and cold seeps. Here we investigated the biogeochemical and microbiological processes leading to the development of sulfidic niches by deploying wood colonization experiments at a depth of 1690 m in the Eastern Mediterranean for one year. Wood-boring bivalves of the genus Xylophaga played a key role in the degradation of the wood logs, facilitating the development of anoxic zones and anaerobic microbial processes such as sulfate reduction. Fauna and bacteria associated with the wood included types reported from other deep-sea habitats including chemosynthetic ecosystems, confirming the potential role of large organic food falls as biodiversity hot spots and stepping stones for vent and seep communities. Specific bacterial communities developed on and around the wood falls within one year and were distinct from freshly submerged wood and background sediments. These included sulfate-reducing and cellulolytic bacterial taxa, which are likely to play an important role in the utilization of wood by chemosynthetic life and other deep-sea animals. PMID:23301092

RESISTANCE TO THE ATTACK OF DRY-WOOD TERMITES (Cryptotermes brevis OF SIX WOOD SPECIES

Directory of Open Access Journals (Sweden)

Fabrício Gomes Gonçalves

2006-03-01

Full Text Available The dry wood termites are one of the largest causes of damages in wood used in Brazil. This work analyzed the attackof the Cryptotermes brevis in six commercials wood species in the north of the Rio de Janeiro and south of the Espírito Santo. The testobserved the number of holes, the percentage of died individuals and the damage of the pieces. When compared to the Pinus sp(reference, the species with less susceptibility to the attack were Cedrela fissilis, Cariocar brasiliense and Goupia glabra, that alsopresented the largest percentages of mortality of termites. The Schizolobium parahyba, Toona ciliata and the Tachigalia myrmecophyllawere the species with the highest level of damage.

Applicability of Vegetable Oils as a Wood Preservative

Directory of Open Access Journals (Sweden)

Eylem Dizman Tomak

2012-04-01

Full Text Available Conventional heavy duty wood preservatives have been banned or restricted for some applications due to their mammalian toxicity and their adverse effect on the environment. New, eco-friendly, but nevertheless still effective protection systems, is needed to protect wood in outdoors. Non-toxic vegetable oils can form of a protective layer on the surface of the wood cells which decrease water uptake of wood. For that reason, oils have a good potential as being a wood preservative. However, impregnation with vegetable oils is insufficient to impart adequate biological decay and termite resistance, and indeed the treatment may increase wood’s propensity to burn. In addition, a high level of oil absorption required for good protection make the process impractical and uneconomic to use. The efficiency of the treatment can be improved with using the biocides and oils together. Beside this, usage of modified oils can decrease the retention levels in wood. In this study, applicability of vegetable oils being one of the environment-friendly, biodegradable water repellents on wood treatments was reported. Furthermore, problems related to the use of oils for wood protection, and possible solutions for the problems were discussed.In this study, applicability of vegetable oils as one of the environment-friendly, biodegradable water repellents was reported. Furthermore, problems related to the use of oils for wood protection and possible solutions for the problems were discussed

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

Wood waste: A disposal problem or an opportunity?

International Nuclear Information System (INIS)

Vajda, P.

1989-01-01

The utilization of wood wastes in North America is reviewed, with a focus on the wood products industry and markets. On the whole, wood mill residues in North America have always been utilized except for a period from the 1940s to the 1970s oil crisis. In the latter period, low cost electric power and hydrocarbon fuels rendered uneconomical the use of wood wastes as fuel. As a response to the problem of disposing these wastes, a number of innovations occurred in that period, including the use of wood chips for manufacturing pulp and particleboard, and the use of sawdust and shavings for manufacturing hardboard and medium density fiberboard. Uses for bark, except as fuel, have not been successfully developed. Since the 1970s, wood waste in the USA is essentially all used for composite board products and fuel. This is also true in eastern Canada, which is close to the wood products markets and which has fairly high oil and gas costs. However, in western Canada, low energy costs and small internal markets have led to a serious wood waste disposal problem. A survey of wood waste supply and demand shows large surpluses in mill residues in western Canada and some remote locations in northern Ontario and Quebec. The Pacific Rim countries are identified as a potential market for western Canadian composite board production. The use of other sources of wood waste (forestry or logging residues, which are costly to collect, and municipal construction waste) is briefly discussed

Great War legacies in Serbian culture

Directory of Open Access Journals (Sweden)

Milojković-Đurić Jelena

2015-01-01

Full Text Available In the aftermath of the Great War, Ivo Andrić published a number of poems, essays and short stories describing the hard-won victorious outcome as transient to the dire reality of the inordinate loss of human lives and suffering. Yet, personal experiences, although perceived as ephemeral, helped to define the historical discourse capturing man’s resolve to persist in his chosen mission. Over time, Serbian literature and fine arts sustained an unfinished dialogue of the past and the present, merging the individual voices with the collective voices to construct the national narrative. The young writer Miloš Crnjanski observed the sights of destruction and despair that seemed to pale in new literary works pertaining to the war. His novel A Diary about Čarnojević was closely related to his own perilous wartime journey as a conscript in the Austrian army. The vastness of Pannonian plains and Galician woods must have invoked a comparison of sorts with another historic chapter recorded in the collective consciousness of his nation: the Great Migration of Serbs led by Patriarch Arsenije III Čarnojević (Crnojević in 1690. The very title of the novel contained a powerful reference to the migration, and its illustrious historic leader which has not been discussed or explored before.

Wood for energy production. Technology - environment - economy

International Nuclear Information System (INIS)

Serup, H.; Falster, H.; Gamborg, C.

1999-01-01

'Wood for Energy Production', 2nd edition, is a readily understood guide to the application of wood in the Danish energy supply. The first edition was named 'Wood Chips for Energy Production'. It describes the wood fuel from forest to consumer and provides a concise introduction to technological, environmental, and financial matters concerning heating systems for farms, institutions, district heating plants, and CHP plants. The individual sections deal with both conventional, well known technology, as well as the most recent technological advances in the field of CHP production. The purpose of this publication is to reach the largest possible audiance, and it is designed so that the layman may find its background information of special relevance. 'Wood for Energy Production' is also available in German and Danish. (au)

Wood for energy production. Technology - environment - economy

Energy Technology Data Exchange (ETDEWEB)

Serup, H.; Falster, H.; Gamborg, C. [and others

1999-10-01

`Wood for Energy Production`, 2nd edition, is a readily understood guide to the application of wood in the Danish energy supply. The first edition was named `Wood Chips for Energy Production`. It describes the wood fuel from forest to consumer and provides a concise introduction to technological, environmental, and financial matters concerning heating systems for farms, institutions, district heating plants, and CHP plants. The individual sections deal with both conventional, well known technology, as well as the most recent technological advances in the field of CHP production. The purpose of this publication is to reach the largest possible audiance, and it is designed so that the layman may find its background information of special relevance. `Wood for Energy Production` is also available in German and Danish. (au)

Wood-burning appliances and indoor air quality

Energy Technology Data Exchange (ETDEWEB)

Levesque, Benoit; Allaire, Sylvain; Gauvin, Denis; Gingras, Suzanne; Rhainds, Marc; Prud' Homme, Henri; Duchesne, Jean-Francois [CHUQ-Centre de Recherche du CHUL, Unite de Recherche en Sante Publique, 2400, d' Estimauville, Beauport, G1E 7G9 Quebec (Canada); Koutrakis, Petros [Harvard School of Public Health, 677 Huntington Avenue, Boston, MA 02115 (United States)

2001-12-17

Wood heating represents an interesting economic alternative to electrical or heating oil and gas systems. However, many people are concerned about poor indoor air quality in homes equipped with wood-burning appliances. We conducted a study in the Quebec City region (Canada) to verify the extent of indoor air contamination, and to examine the frequency of respiratory symptoms and illnesses among occupants of wood-heated homes. One child attending primary school (median=8 years old; range=5-14 years old) and an adult (median=37 years old; range=23-52 years old) were recruited in each eligible house. Eligible houses were without known sources of combustion products (smokers, attached garage, oil or gas furnace, gas stove, etc.) except for wood-burning appliance. Out of the 89 houses included in the study, 59 had wood-burning appliances. Formaldehyde, nitrogen dioxide, respirable particles (PM10) and carbon monoxide were measured in a sub-set of 49 houses (41 with a wood-burning appliance and 8 without). The frequency of respiratory symptoms and diseases among participants were documented using a daily symptom diary. Concentrations of contaminants were low in most houses, both with or without a wood-burning appliance. Globally, there was no consistent relationship between the presence of a wood-burning appliance and respiratory morbidity in residents. Nevertheless, residents who mentioned being exposed to fumes emitted by such an appliance reported more respiratory illnesses and symptoms. The presence of animals or molds, and keeping windows closed most of the time in winter were other factors associated with respiratory problems. We conclude that wood burning appears to be a respiratory health risk for occupants if the appliance is not maintained and used properly.

The use of wood waste for energy production

International Nuclear Information System (INIS)

Karlopoulos, E.; Pavloudakis, F.

1999-01-01

The paper presents some technical aspects and management issues of wood waste reuse end disposal. It refers to the Greek and European legislation which determines the framework for rational and environmental friendly practices for woos waste management. It refers also to the wood waste classification systems and the currently applied methods of wood waste disposal and reuse. Emphasis is given to the wood waste-to-energy conversion system, particularly to the pretreatment requirements, the combustion techniques, and the environmental constrains. Finally, the decision making process for the investments in the wood waste firing thermal units is discussed

Comparative ecobalancing accounting of semi-central house heat supply from wood residues

International Nuclear Information System (INIS)

Biemann, Kirsten

2015-01-01

impact. Heat demanders and network structure vary for the different settlement types. This impacts the heat losses and the amount of energy generated from wood in the network. Combined heat and power plants promise higher fuel utilization. They decrease costs and environmental impacts. The heat losses in the network vary greatly between 23 percent for small single-family houses and 4 percent for big multi-family buildings. Therefore networks with bigger heat demanders have lower environmental burdens. From an economic point of view the conversion from a gas heater to the connection of a multi- family building to a semi- centralized heating network using wood residues as fuel is worthwhile. However for a single-family building this is often not the case. A comparison between the semi- centralized heat supply from wood residues and the commonly used heat supply from gas heaters shows a large potential to decrease greenhouse gas emissions, ozone depletion and fossil resource usage when using the first variant. However, it increases particulate matter formation, photochemical oxidant formation, eutrophication, and acidification. Only the usage of a wood gasification and a combined heat and power plant decreases particulate matter formation slightly. Similar results were obtained for a centralized heating network using wood residues as fuel. Using wood heaters in the buildings further decreases greenhouse gas emissions, ozone depletion and fossil resources, but results in an increased particulate matter formation. This particulate matter formation is over 1.000 percent bigger than for gas heaters.

The potential of wood-based composite poles

Science.gov (United States)

Todd F. Shupe; Cheng Piao; Chung Y. Hse

2009-01-01

Wood-based composite utility poles are receiving increasing attention in the North American pole market. This interest is being driven by many increasing factors such as increasing: (1) disposal costs of solid wood poles, (2) liability and environmental concerns with traditional means of disposal of solid wood poles, (3) cost and concerns of long-term...

Structural condition assessment of in-service wood

Science.gov (United States)

Robert J. Ross; Brian K. Brashaw; Xiping Wang

2006-01-01

Wood is used extensively for both interior and exterior applications in the construction of a variety of structures (residential, agricultural, commercial, government, religious). The deterioration of an in-service wood member may result from a variety of causes during the life of a structure. It is important, therefore, to periodically assess the condition of wood...

Insect-mediated nitrogen dynamics in decomposing wood

Science.gov (United States)

Michael D. Ulyshen

2015-01-01

1.Wood decomposition is characterised by complex and poorly understood nitrogen (N) dynamics with unclear implications for forest nutrient cycling and productivity.Wood-dwelling microbes have developed unique strategies for coping with the N limitations imposed by their substrate, including the translocation of N into wood by cord-forming fungi and the fixation of...

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....

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.

Wood fuels sources and markets

International Nuclear Information System (INIS)

Koopmans, Auke

2003-01-01

Biomass energy is an important source of energy in most Asian countries. Households and industries use substantial amounts of fuel wood, charcoal and other biomass energy, such as agricultural residues, dung, leaves and sawmill residues. The main household applications are cooking and heating whereas industrial applications range widely. This paper provides an overview of estimates on the production and trade of biomass fuels in the South-east Asia region. The flows and channels used in the supply of wood fuels in different countries were analysed. This paper may help in identifying policy gaps with regards to the supply and consumption of wood fuels from both forest and non-forest sources. (Author)

Aquatic wood -- an insect perspective

Science.gov (United States)

Peter S. Cranston; Brendan McKie

2006-01-01

Immersed wood provides refugia and substrate for a diverse array of macroinvertebrates, and food for a more restricted genuinely xylophagous fauna. Worldwide, xylophages are found across aquatic insect orders, including Coleoptera, Diptera, Trichoptera and Plecoptera. Xylophages often are specialised, feeding on the wood surface or mining deep within. Many feed...

Turbulence and Araki-Woods factors

DEFF Research Database (Denmark)

Sasyk, R.; Törnquist, A.; Törnquist, Asger Dag

2010-01-01

Using Baire category techniques we prove that Araki-Woods factors are not classifiable by countable structures. As a result, we obtain a far reaching strengthening as well as a new proof of the well-known theorem of Woods that the isomorphism problem for ITPFI factors is not smooth. We derive...

Wood-burning stoves worldwide

DEFF Research Database (Denmark)

Luis Teles de Carvalho, Ricardo

global environmental health risk, since these sources are important contributors to fine particulate matter (PM2.5) in the ambient air that increase climate and health risks. This thesis explores the social-technical dimensions of both the use of wood-burning stoves (WBSs) and transition to the use......More than any time in our history, the wood-burning stove continues to be the most popular technology used for cooking and heating worldwide. According to the World Health Organization and recent scientific studies, the inefficient use of solid-fuels in traditional stoves constitutes the major...... systems, improved efficient retrofits and advanced stove innovations. In chapter 3, four popular wood-burning practices found in five countries were singled-out to be examined closely in four case studies: “cooking in Brazil”, “cooking and heating in Peru”, “heating in Portugal” and “recreational heat...

Wood-plastic composites utilizing wood flours derived from fast- growing trees common to the midwest

Science.gov (United States)

There are several non- or under-utilized hardwood trees common to the Midwestern states. Wood flour (WF) derived from fast-growing Midwest trees (Osage orange, Black Locust and Red Mulberry) were evaluated as a source of bio-based fiber reinforcements. Wood plastic composites (WPC) of high density p...

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

Advances and challenges of wood polymer composites

Science.gov (United States)

Roger M. Rowell

2006-01-01

Wood flour and fiber have been blended with thermoplastic such as polyethylene, polypropylene, polylactic acid and polyvinyl chloride to form wood plastic composites (WPC). WPCs have seen a large growth in the United States in recent years mainly in the residential decking market with the removal of CCA treated wood decking from residential markets. While there are...

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.

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...

Wood Flour Moulding Technology: Implications for Technical ...

African Journals Online (AJOL)

User

2011-04-19

Apr 19, 2011 ... be waste product from saw mills, wood working plants or produced from selected dry wood by .... Stop watch-used to indicate the exact time the mould has remained in the press before wood .... There is abundance of saw dust the source of which is the ... Madison, Wisconsin: Wiley Interscience. Usoro, H. S. ...

Low-NO{sub x}, wood chip combustion

Energy Technology Data Exchange (ETDEWEB)

Saastamoinen, J.; Oravainen, H.; Haemaelaeinen, J.; Paakkinen, K. [VTT Energy, Jyvaeskylae (Finland)

1997-10-01

The regulations for nitrogen oxide emissions vary in different countries, but the general trend in the future will probably be that the emissions limits will be lowered also for wood combustion plants, which are small or medium size units. Thus, the development of wood chip burning furnaces (grate furnaces, fluidized bed combustors, stoker furnaces) with lower nitrogen oxide emissions, is important. The wood used in the combustor, its particle size, moisture and fuel properties (nitrogen content) affect the nitrogen emissions. The nitrogen oxide release is also much affected by the design and operation of the combustor (air staging, fuel air preheat, flue gas circulation, air to fuel mass ratio). The fate of nitrogen compounds originally in the virgin wood depends much on the design of the combustor system and by proper planning it is possible to reduce the emission of nitrogen oxides. Basic knowledge of the release of nitrogen compounds from single wood particles is attained. The release of gaseous nitrogen compounds from wood particles during pyrolysis and combustion is studied experimentally and by modelling. Nitrogen release is studied experimentally by two ways, by analysing the gas and by quenching the particle and analysing the char residue. Formation of nitrogen oxide emissions in a fuel bed is studied by modelling and by combustion experiments with a pot furnace. This research gives general information of nitrogen oxide formation in wood bunting especially in fixed beds. The development of a horizontal stoker burner for wood chips with low emissions is the practical aim of the research. (orig.)

Violates stem wood burning sustainable development?

DEFF Research Database (Denmark)

Czeskleba-Dupont, Rolf

2008-01-01

friendly effects of substituting wood burning for fossil fuels. With reference to Bent Sørensen's classical work on 'Renewable Energy' the assumption of CO2-neutrality regarding incineration is problematised when applied to plants with long rotation periods as trees. Registered CO2-emissions from wood...... burning are characterised together with particle and PAH emissions. The positive treatment of wood stove-technology in the Danish strategy for sustainable development (draft 2007) is critically evaluated and approaches to better regulation are identified....

Mechanics of the Compression Wood Response: II. On the Location, Action, and Distribution of Compression Wood Formation.

Science.gov (United States)

Archer, R R; Wilson, B F

1973-04-01

A new method for simulation of cross-sectional growth provided detailed information on the location of normal wood and compression wood increments in two tilted white pine (Pinus strobus L.) leaders. These data were combined with data on stiffness, slope, and curvature changes over a 16-week period to make the mechanical analysis. The location of compression wood changed from the under side to a flank side and then to the upper side of the leader as the geotropic stimulus decreased, owing to compression wood action. Its location shifted back to a flank side when the direction of movement of the leader reversed. A model for this action, based on elongation strains, was developed and predicted the observed curvature changes with elongation strains of 0.3 to 0.5%, or a maximal compressive stress of 60 to 300 kilograms per square centimeter. After tilting, new wood formation was distributed so as to maintain consistent strain levels along the leaders in bending under gravitational loads. The computed effective elastic moduli were about the same for the two leaders throughout the season.

Effects of the "great recession" on the forest products sector in the northern region of the United States

Science.gov (United States)

Christopher W. Woodall; William G. Luppold; Peter J. Ince; Ronald J. Piva; Kenneth E. Skog

2012-01-01

The forest industry within the northern region of the United States has demonstrated a notable decline in terms of employment, number of mills, wood consumption, and forest harvests since 2000--a downturn exacerbated by the "Great Recession" of 2007-2009. Longer term industrial decline (since 2000) has been evidenced by reductions in secondary product (e.g.,...

Broad Anatomical Variation within a Narrow Wood Density Range—A Study of Twig Wood across 69 Australian Angiosperms

Science.gov (United States)

Ziemińska, Kasia; Westoby, Mark; Wright, Ian J.

2015-01-01

Objectives Just as people with the same weight can have different body builds, woods with the same wood density can have different anatomies. Here, our aim was to assess the magnitude of anatomical variation within a restricted range of wood density and explore its potential ecological implications. Methods Twig wood of 69 angiosperm tree and shrub species was analyzed. Species were selected so that wood density varied within a relatively narrow range (0.38–0.62 g cm-3). Anatomical traits quantified included wood tissue fractions (fibres, axial parenchyma, ray parenchyma, vessels, and conduits with maximum lumen diameter below 15 μm), vessel properties, and pith area. To search for potential ecological correlates of anatomical variation the species were sampled across rainfall and temperature contrasts, and several other ecologically-relevant traits were measured (plant height, leaf area to sapwood area ratio, and modulus of elasticity). Results Despite the limited range in wood density, substantial anatomical variation was observed. Total parenchyma fraction varied from 0.12 to 0.66 and fibre fraction from 0.20 to 0.74, and these two traits were strongly inversely correlated (r = -0.86, P area to sapwood area ratio, and modulus of elasticity (0.24 ≤|r|≤ 0.41, P area to sapwood area ratio (0.47 ≤|r|≤ 0.65, all P area spectrum. The fibre-parenchyma spectrum does not yet have any clear or convincing ecological interpretation. PMID:25906320

Broad Anatomical Variation within a Narrow Wood Density Range--A Study of Twig Wood across 69 Australian Angiosperms.

Science.gov (United States)

Ziemińska, Kasia; Westoby, Mark; Wright, Ian J

2015-01-01

Just as people with the same weight can have different body builds, woods with the same wood density can have different anatomies. Here, our aim was to assess the magnitude of anatomical variation within a restricted range of wood density and explore its potential ecological implications. Twig wood of 69 angiosperm tree and shrub species was analyzed. Species were selected so that wood density varied within a relatively narrow range (0.38-0.62 g cm-3). Anatomical traits quantified included wood tissue fractions (fibres, axial parenchyma, ray parenchyma, vessels, and conduits with maximum lumen diameter below 15 μm), vessel properties, and pith area. To search for potential ecological correlates of anatomical variation the species were sampled across rainfall and temperature contrasts, and several other ecologically-relevant traits were measured (plant height, leaf area to sapwood area ratio, and modulus of elasticity). Despite the limited range in wood density, substantial anatomical variation was observed. Total parenchyma fraction varied from 0.12 to 0.66 and fibre fraction from 0.20 to 0.74, and these two traits were strongly inversely correlated (r = -0.86, P area to sapwood area ratio, and modulus of elasticity (0.24 ≤|r|≤ 0.41, P area to sapwood area ratio (0.47 ≤|r|≤ 0.65, all P area spectrum. The fibre-parenchyma spectrum does not yet have any clear or convincing ecological interpretation.

BASIC DENSITY AND RETRACTIBILITY OF WOOD CLONES OF THREE Eucalyptus SPECIES

Directory of Open Access Journals (Sweden)

Djeison Cesar Batista

2010-12-01

Full Text Available Among the planted forests that supply the national wood industry, the genus Eucalyptus has become the most important, due to its fast growth, ease of large scale planting and variability of wood use. The generation of new hybrids and clones is a reality in the national practice of silviculture, and there is great interest currently in finding genetic improvements, mainly for higher volumetric gains and resistance in rough conditions of planting, such as pest attacks, periods of drought, low soil fertility, etc. The basic density is one of the most important physical properties of wood because it relates directly to other properties, including the anisotropic shrinkage. Such properties indicate the rational use of a species in a certain wood product. The aim of this work was to determine the basic density and the anisotropic shrinkage of five wood clones for each one of the following species: Eucalyptus saligna, Eucalyptus grandis and Eucalyptus dunnii. Clone 5 of Eucalyptus saligna presented the highest basic density (0.56 g/cm³ and was the most dimensionally instable. Of all the species, there was only a direct relation among basic density, maximum volumetric shrinkage and maximum volumetric shrinkage coefficient in this clone. Considering maximum volumetric shrinkage as the criterion, clone 3 was the most dimensionally stable. Clones 2 and 3 of Eucalyptus grandis presented the least and the highest basic density, respectively, with 0.40 and 0.49 g/cm³. It was not possible to distinguish among clones 1, 3 and 4 in terms of dimensional stability, and considering maximum volumetric shrinkage coefficient as the criterion, clone 5 was the most dimensionally instable. For Eucalyptus saligna and Eucalyptus dunnii it was not possible to distinguish which clone presented the least basic density. Clone 3 of Eucalyptus dunnii presented the highest basic density (0.65 g/cm³ and considering maximum volumetric shrinkage coefficient as the criterion, it

One physical educator's career cycle: strong start, great run, approaching finish.

Science.gov (United States)

Woods, Amelia Mays; Lynn, Susan K

2014-03-01

This article is nested within a longitudinal project examining 6 teachers' journeys along their career cycles (Lynn & Woods, 2010; Woods & Earls, 1995; Woods & Lynn, 2001). Two participants from the initial 6 continue to teach K-12 physical education; 1 of these participants, Everett, is examined in the current study. This veteran teacher's career-cycle movement and the environmental factors that both enhanced and constrained his career development are examined through the lens of Fessler and Christensen's career cycle model (1992). Data sources included: 8 formal interviews with Everett; formal interviews with his university teacher educators, student-teacher supervisor, principal, and spouse; informal interviews; field notes; and systematic teaching observations. An interpretative framework was used to assess the perceptions and meanings Everett gave to experiences as a physical educator and coach. Several factors acutely influenced Everett's career progression, including: (a) his individual disposition, (b) the impact and continued influence of a professional preparation program, and (c) his school and community support. He entered the profession with great promise and spent most of his career in the enthusiastic and growing, and the career stability, stages before shifting into the career frustration stage where he currently remains. Everett was able to negotiate personal and organizational environmental factors that have been identified as barriers for some physical educators. Therefore, viewing his professional life through the lens of the career cycle provides insights into the areas of change necessary to motivate and retain high-quality physical educators such as Everett.

Cytochemical localization of cellulases in decayed and nondecayed wood

Energy Technology Data Exchange (ETDEWEB)

Murmanis, L.; Highley, T.L.; Palmer, J.G.

1987-01-01

Sawdust from undecayed western hemlock wood and from wood previously decayed by the brown-rot fungus Poria placenta or by the white-rot fungus Ganoderma applanatum was incubated with commercial cellulase from Trichoderma viride. Samples were treated cytochemically to locate cellulase activity and examined by TEM. Results showed that cellulase degraded undecayed wood extensively, with the attack starting on the outer border of a cell wall and progressing inside. Wood decayed by P. placenta, with or without cellulase incubation, and treated by the cytochemical test showed uniform distribution of electron dense particles throughout the cell walls. In wood decayed by G. applanatum, cellulase degradation was similar to that in undecayed wood. From measurements of particle diameter it is suggested that electron dense particles are cellulase. It is concluded that brown-rot and white-rot fungi have different effects on the microstructure of wood. The brown-rot fungus appears to open the wood microstructure so that cellulase can diffuse throughout the degraded tracheid wall.

Feasibility of biodegradation of pentachlorophenol in scrap wood

International Nuclear Information System (INIS)

Beaulieu, G.; Besner, A.; Gilbert, R.; Tetreault, P.; Beaudet, R.; Bisaillon, J. G.; Lepine, F.; Ottou, J. M.; Sansregret, J. L.; Lei, J.

1998-04-01

The feasibility of biological treatment of scrap wood impregnated in pentachlorophenol (PCP) was investigated using wood samples impregnated with PCP for biodegradation experiments by the Hydro-Quebec Research Institute (IREQ). IREQ identified the necessity of pre-treating the wood, first by shredding wood poles into wood shavings, followed by mechanical milling of the shavings to obtain wood dust. Biodegradation experiments under anaerobic conditions were performed by the Armand-Frappier Institute by isolating a consortium of bacteria from a mixture of PCP-contaminated soils and a municipal anaerobic sludge that was able to degrade PCP under anaerobic methanogenic conditions at 29 degrees C. A complementary source of carbon was found to be necessary for the bacterial consortium to degrade the PCP. The best PCP degradation results were obtained with an aerobic fixed-film reactor. Aerobic biodegradation tests were performed on liquor extracted from wood dust contaminated with PCP. The anaerobic fixed field reactor was able to completely degrade the PCP extracted from wood dust in less than one day. Aerobic biodegradation was also investigated using microorganisms and fungi. Over a four month experimental period only low concentrations of PCP were found in effluents treated with the aerobic cultures. 117 refs., 38 tabs., 31 figs

Wood evidence : proper collection, documentation, and storage of wood evidence from a crime scene

Science.gov (United States)

Alex Wiedenhoeft

2006-01-01

Wood can be found at crime scenes in many forms: as a murder weapon, as material used to hide a body, or as trace evidence from forced entry or vandalism. In the course of my work at the Forest Products Laboratory, Center for Wood Anatomy Research, I have been part of several forensic investigations that were adversely affected by inappropriate procedures used to...

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.

Three Construction Projects with Wood Scraps

Science.gov (United States)

Levine, Elizabeth

1977-01-01

Wood, a natural material, appeals to children of all ages. Wood construction allows children the flexibility of moving parts of their work around until they are satisfied with the arrangement. Three projects are described. (Author/RK)

Effect of wood flour content on the optical color, surface chemistry, mechanical and morphological properties of wood flour/recycled high density polyethylene (rHDPE) composite

Science.gov (United States)

Sheng, Chan Kok; Amin, Khairul Anuar Mat; Kee, Kwa Bee; Hassan, Mohd Faiz; Ali, E. Ghapur E.

2018-05-01

In this study, effect of wood flour content on the color, surface chemistry, mechanical properties and surface morphology of wood-plastic composite (WPC) on different mixture ratios of recycled high density polyethylene (rHDPE) and wood flour were investigated in detail. The presence of wood flour in the composite indicates a significant total color change and a decrease of lightness. Functional groups of wood flour in WPC can be seen clearer from the Fourier transform infrared (FTIR) spectra as the wood flour content increases. The mechanical tensile testing shows that the tensile strength of Young's modulus is improved, whereas the strain and elongation at break were reduced by the addition of wood flour. The gap between the wood flour microvoid fibre and rHDPE matrix becomes closer when the wood flour content is increased as observed by scanning electron microscope (SEM) image. This finding implies a significant improvement on the interaction of interfacial adhesion between the rHDPE matrix and wood flour filler in the present WPC.

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.

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....

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...

49 CFR 178.515 - Standards for reconstituted wood boxes.

Science.gov (United States)

2010-10-01

... wood boxes. (a) The identification code for a reconstituted wood box is 4F. (b) Construction requirements for reconstituted wood boxes are as follows: (1) The walls of boxes must be made of water... 49 Transportation 2 2010-10-01 2010-10-01 false Standards for reconstituted wood boxes. 178.515...

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

African Journals Online (AJOL)

In this study, the reactivity of wood components with acetic anhydride or vinyl acetate was studied. It was found that the reactivity of wood components was virgin wood flour > holocellulose >> a-cellulose. Acetylation of Turkish pine or cedar wood flour with acetic anhydride was significantly improved in the presence of ...

Study of radiation-destroyed wood

International Nuclear Information System (INIS)

Klimentov, A.S.; Shakhanova, R.K.; Stepanova, I.N.; Vysotskaya, I.F.

1986-01-01

The change in carbohydrate composition of aspen wood exposed to electron beam radiation (0.5 MeV, dose rates of 0-0.56 MGy) is studied. It has been found that the water-soluble polysaccharide content grows from 0.47 up to 8.54 %, and that of the non-hydrolyzed polysaccharides decreases from 49.4 down to 36.1 %. The polysaccharide total content of aspen wood goes down from 61.28 to 56.82 % with the radiation dose increasing. Consequently, the xylose, arabinose, and ramnose percentage of wood hydrolyzates increases correspondingly from 11.9 up to 15.44, from 0.66 up to 0.90, and from 0.21 up to 0.38

Wood anatomy of Argyroxiphium (Asteraceae): adaptive radiation and ecological correlations

International Nuclear Information System (INIS)

Carlquist, S.

1997-01-01

Wood anatomy shows close correlation with ecology: A. kauense, A. sandwicense (stem), and A. virescens, which occur in dry localities, show xeromorphic wood patterns. The most mesomorphic woods are those of the bog species A. grayanum and root wood of A. sandwicense. The wood of A. caliginis is xeromorphic, despite the bog habitat of the species, a fact explainable if A. caliginis is a recent entrant into the bog habitat Libriform wall thickness appears correlated with habit. Quantitative features of stem woods of Argyroxiphium are comparable to woods ranging from desert to moist montane forest areas in California. The similarities to woods from each Californian habitat are correlative to the relative moisture availability of the respective Hawaiian habitats of the Argyroxiphium species. (author)

Introducing wood pellet fuel to the UK

Energy Technology Data Exchange (ETDEWEB)

Cotton, R A; Giffard, A

2001-07-01

Technical and non-technical issues affecting the introduction of wood pellet-fired heating to the UK were investigated with the aim of helping to establish a wood pellet industry in the UK. The project examined the growth and status of the industry in continental Europe and North America, reviewed relevant UK standards and legislation, identified markets for pellet heating in the UK, organised workshops and seminars to demonstrate pellet burning appliances, carried out a trial pelletisation of a range of biomass fuels, helped to set up demonstration installations of pellet-fired appliances, undertook a promotional campaign for wood pellet fuel and compiled resource directories for pellet fuel and pellet burning appliances in the UK. The work was completed in three phases - review, identification and commercialisation. Project outputs include UK voluntary standards for wood pellet fuel and combustion appliances, and a database of individuals with an interest in wood pellet fuel.

X-ray measurements on wood - spectra measurements

DEFF Research Database (Denmark)

Jensen, Signe Kamp; Thygesen, Lisbeth Garbrecht; Gerward, Leif

The report concerns simultaneous non-destructive measurements of water content and density of wood. Theoretically, this should be possible using a x-ray equipment newly build at BKM, and this work is an attempt to use the equipment for assessing water content and density of wood samples under...... laboratory conditions. A number of wood samples with different densities are placed at different relative humidities from 0.5 to 97 %RH. When equilibrium is obtained the samples are measured with the x-ray equipment such that 10 points are measured in the sample followed by measurements outside the sample...... (free-scanning). In this way 100 points are measured for each wood sample. This produces information about moisture content and density of the samples as water and wood attenuations of the x-rays are different for the different energy levels contained in the x-rays. The "real" density and moisture...

Acidity of selected industrial wood species in Serbia

Directory of Open Access Journals (Sweden)

Popović Mlađan

2016-01-01

Full Text Available The acidity of wood has an important role in many areas of wood applications. Hence, this paper presents a study on the acidity of beech, fir and poplar, as the representatives of the most industrially utilized wood species in Serbia. The contents of both the soluble and insoluble acids were determined through the extraction methods with cold distilled water and sodium acetate solution, respectively, followed by the titration with sodium hydroxide solution. The acidity strongly differs among the three wood species used in this research. The amount of insoluble acids was the highest in fir, almost twice as much than in poplar, and about 68 % higher than in fir wood species. Such differences also showed a strong correlation with the gel times of UF adhesive mixes with hot water extracts. [Projekat Ministarstva nauke Republike Srbije, br. TP 31041: Establishment of Wood Plantations Intended for Afforestation of Serbia

Wood versus quality of the air?

International Nuclear Information System (INIS)

Richard, A.

2015-01-01

CITEPA has estimated at 875000 tonnes the releases of fine particles in France in 2014. Wood heating is responsible for 1/3 of the release of PM10 particles (particles with a diameter lower than 10 μm) and for half of the release of PM2.5 particles. PM2.5 particles are particles whose diameter is lower than 2.5 μm, they are more dangerous than PM10 particles because they enter the lungs more deeply. In 2012 the World Health Organisation acknowledged fine particles as responsible for lung cancers. The other contributors are industry (20 to 30%) and transport (16%). The uncertainties on the figures are important and can reach 50% as the estimations are based on extrapolations but wood heating appears to be the major polluter. The solution is to promote the installation of new wood heating systems that release far less particles. Open fireplaces and closed fireplaces installed before 2002 release respectively 97 and 91 kg of fine particles a year while closed fireplaces installed after 2007 release only 8 kg a year and the latest closed systems only 3 kg a year. In some mountainous regions like Haute-Savoie where wood heating is a tradition, local authorities give financial helps to individuals to install efficient systems. Community wood heating and industrial wood boilers have been equipped with efficient filters since the first Grenelle law on the environment took effect and their releases of fine particles have dropped sharply. (A.C.)

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...

Holistic approach to wood protection

Science.gov (United States)

Roger M. Rowell

2006-01-01

When untreated wood is exposed to adverse outdoor conditions, nature has a series of chemistries to degrade it to its original building blocks of carbon dioxide and water. Fungi, termites, heat, moisture, ultraviolet (UV) energy, and chemicals take their toll on the performance properties of wood. We tend to study each of these degradation chemistries as individual...