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1.
Silicic acid: boric acid complexes as wood preservatives 总被引：1，自引：0，他引：1
Haruhiko Yamaguchi 《Wood Science and Technology》2003,37(3-4):287-297
Wood was treated with a low molecular-weight silicic acid: boric acid agent and examined for increased resistance to termites and combustion. Wood treated with silicic acid only exhibited increased termite resistance, but not to the marked extent observed after treatment with a mixture of silicic and boric acids. Increasing the quantity of boric acid also increased the termite mortality rate and shortened the time to death. Oral-toxicity tests using dyed silicic acid: boric acid suggested that the boric acid in the agent acted as a stomach poison. Field tests on stakes over three years showed that even if stakes were placed near the termite exit, those treated with silicic acid and high levels of boric acid had no attack by termites and maintained their original form. Though these specimens were installed in the field during three rainy seasons (about six months in total) in three years, the termite resistance ability of these chemicals was maintained. It became clear that this silicic acid: boric acid agent has a high water resistance ability worthy of application in the outdoors. Combustion tests showed that flame and glowing combustion times were shortened at high levels of boric acid. When a boric acid: methanol solution was added at of rate of not less than 25 ml for 100 g of colloidal silicic acid solution (CSAS), flaming and glowing combustion were not observed. Although the charring length of the wood specimen which was treated with a low molecular weight silicic acid: boric acid agent decreased to 2/3 of that of the control wood, the charring lengths were not influenced by the level of boric acid. However, the volume of smoke decreased relative to the amount of boric acid that had been added. 相似文献
2.
We examined the ability of chemically modified tannin and tannin-copper complexes to penetrate wood and the ability of the treated wood to resist termites. Only the tannin-treated wood retained the agents after treatment. Wood with untreated mimosa tannin (MT) retained the least amount, followed by wood with resorcinolated tannin (RMT) and that with catecholated tannin (CMT). When RMT or CMT was mixed with ammonia-copper, the wood retained twice as much of these solutions as the MT -ammonia-copper solution. The degree of retention of RMT-NH3-Cu and CMT-NH3-Cu ranged from 268 to 326kg/m3. The solutions penetrated 2–13 mm from the tangential sections of the logs. We also measured the termite resistance conferred by these solutions. Most of the tannin-NH3-Cu solutions showed contact lethality for termites in the contact toxicity test. However, the termites were fed cellulose treated with those solutions and most survived the oral toxicity test (14 days). Moreover, these solutions reduced the amount of damage to the wood by termites. However, the mortality rate of the termites during the eating-damage test (>21 days) did not reach 100% for any of the solutions except for RMT. As a result of the field stake test with the same log's used for the penetrability test, the mass loss of wood treated with RMT or CMT alone or with RMT + NH3 + CuCl2, was about one-third to one-half that of the controls. Because these solutions have good wood penetrability and good termite resistance, they have potential use as low-toxicity wood preservatives. 相似文献
3.
Mustafa Kemal Yalinkiliç Tsuyoshi Yoshimura Munezoh Takahashi 《Journal of Wood Science》1998,44(2):152-157
Phenylboronic acid (PBA) was tested in terms of boron leachability from treated wood. In addition, the fungal and termiticidal efficacy of PBA-impregnated sugi (Cryptomeria japonica D. Don) wood was tested against the decay fungi Coriolus versicolor (L. ex Fr.) Quel. and Tyromyces palustris (Berk. et Curt) Murr., representing white-rot and brown-rot fungi, respectively, and the Formosan subterranean termite Coptotermes formosanus Shiraki. Ion chromatography analysis of hot water extracts of treated wood before and after leaching indicated that PBA is considerably resistant to water leaching, and saturation of the treatment solution increased the fixation ratio of boron in wood, whereas boric acid could not remain in wood impregnated even with the saturated solution. Decay test results revealed the excellent bioactive performance of PBA. Wood treated with 0.34% PBA solution was found resistant to both decay fungi, even after running-water leaching for 10 days and treatment with 1.00% PBA completely inactivated the Formosan subterranean termite for the leached specimens. Weight gain levels were 0.18% w/w (0.46kg/m3) and 0.99% w/w (2.49kg/m3) for these concentration levels, respectively, after being leached by running water. Contrary to the general belief that boron is a slow-acting toxicant against termites and unable to prevent mass loss of treated wood, PBA acted rapidly, and the mass loss caused by termites was low.This study was presented in part at the 47th annual meeting of the Japan Wood Research Society, Kochi, April, 1997 相似文献
4.
Spatial distribution, abundance and assemblage of termites depend mainly on the local conditions and habitats in which they thrive. Striking differences are observed in the species richness, number of clades and functional diversity of termite assemblage between different habitats. This study aim was to examine effect of human interference in the diversity of wood destroying termite in forest areas as well as managed and unmanaged plantations in South India. Termites attacking trees and wooden logs were collected from forest areas, managed plantations and unmanaged plantations. The termites collected were identified and compared for species abundance, richness and species diversity. Results show that the species composition and species diversity of the wood destroying termites vary according to the conditions. The species diversity measures revealed that there is a significance variation among the forest fauna and plantations. The forest areas have the highest species composition compared to plantations. Species richness is high forest areas. Even though the abundance of termites are more in unmanaged plantations, there is no significant difference related to species diversity among the managed and unmanaged plantations. 相似文献
5.
铲头堆砂白蚁Cryptotermes declivis Tsai et Chen是破坏木材及木制品的重要干木白蚁,其有翅成虫通过分飞配对后建立新群体,是其重要繁殖扩散途径。本文对铲头堆砂白蚁原始繁殖蚁形成周期进行了研究。以似桂木Paratocarpus sp.、团花Anthocephalus chinensis(Lam.) Rich. et Walp.和球花豆Parkia sp.作为该种白蚁食料,研究其原始繁殖蚁配对后从新建群体的形成到产生下一代的原始繁殖蚁,完成1个世代生活周期。结果表明,铲头堆砂白蚁在室温下,新建群体的形成、发展、发育至下一代原始繁殖蚁形成的周期约5 a,不同寄主材料对铲头堆砂白蚁生活周期没有显著性影响,但与群体数量多少显著相关。本研究首次明确了铲头堆砂白蚁群体发育成熟的周期,对该害虫的检疫与防控研究具有重要参考价值。 相似文献
6.
Effect of an oil heat treatment on the teachability and biological resistance of boric acid impregnated wood 总被引：1，自引：0，他引：1
Florent Lyon Marie-France Thevenon Won-Joung Hwang Yuji Imamura Joseph Gril Antonio Pizzi 《Annals of Forest Science》2007,64(6):673-678
Vegetable oils provide boron retention of about 30% of initial amount depending on oil drying properties. Linseed oil is the most efficient, followed by soybean oil and rapeseed oil. Durability of C. japonica and F. crenata wood specimens has been enhanced by application of linseed oil alone but not enough to reduce termite’s attack of Coptotermes formosanus. Treating wood with a 1.0% w/w boric acid solution prior to oil treatment protects C. japonica from termite and fungi degradations. Efficiency against termites is mainly due to boron retention by oil but hydrophobic oil also forms a barrier decreasing fungi penetration. Boron efficacy threshold around 0.7 kg/m3BAE, lower than classical boron treatments thresholds indicates that oil water-repellence reinforces boron biostatic effect. 相似文献
7.
Gyu-Hyeok Kim Won-Joung Hwang Tsuyoshi Yoshimura Yuji Imamura 《Journal of Wood Science》2010,56(2):166-168
A laboratory no-choice termite bioassay was conducted to evaluate the ability of copper HDO (CX-A or copper xyligen) to protect
radiata pine (Pinus radiata D. Don) wood samples from attack by two subterranean termite species, Reticulitermes speratus and Coptotermes formosanus. A series of sapwood samples were pressure treated with either 0.25%, 0.50%, 0.75%, or 1.00% copper HDO solution. Samples
treated with equivalent concentrations of a benchmark preservative, CCA-C, were used as treated controls. All samples (including
controls) were subjected to an artificial weathering schedule before the bioassay. The samples were exposed to 30-day R. speratus tests and 3-week C. formosanus tests. Copper HDO was shown to deter termites from significant feeding on the treated wood. At a retention of 5.8 kg/m3 (treated
with 0.75% solution) or higher, the mass loss from termite feeding did not exceed 3% for both the 30-day R. speratus tests and the 3-week C. formosanus tests. At each of the retentions tested, copper HDO performed comparably with equivalent retentions of CCA-C; however, field
data are needed to validate these laboratory results. The preliminary findings are that copper HDO pressure treatment has
potential as a viable method of protecting wood from attack by both termite species tested. 相似文献
8.
Charalampos Lykidis Teresa De Troya María Conde Jorge Galván 《Wood material science & engineering》2018,13(1):45-49
The field of wood protection is currently changing due to the restrictions imposed by the Biocidal Products Regulation. The need for development of new wood protection technologies is therefore growing. In this work, the resistance of European beech (Fagus sylvatica L.) wood impregnated with nano-dispersions of zinc oxide (nano-ZnO) and zinc borate (nano-ZnB) against the termite Reticulitermes grassei Clement was investigated. Three different concentrations (0.5%, 1%, 2%) of the nanocompounds were tested. The effects of water leaching were also investigated. A severe effect in terms of termite workers mortality was induced by both dispersions, even at the lowest concentration. In terms of termite feeding, nano-ZnO dispersions appeared to be more efficient than nano-ZnB as they induced significant improvement at concentrations as low as 0.5%. Nano-ZnB was applied at 1% or higher concentrations in order to impart similar changes. Nano-ZnB dispersions were efficient in terms of termite resistance for a concentration at least 1%. Further increasing concentration to 2% resulted in a respective increase of wood efficacy against termites. For both tested nanocompounds, water leaching did not result in any significant increase of termite feeding. 相似文献
9.
Vinícius Gazal Omar Bailez Ana Maria Viana-Bailez Elen L. Aguiar-Menezes Eurípedes B. Menezes 《Wood Science and Technology》2014,48(3):581-590
The termite Nasutitermes corniger is attracted to weathered wood, but it is not known whether this attraction is of chemical or physical nature. This work examines whether wood extracts can change the attraction of N. corniger to a food substrate. In a first experiment, filter paper impregnated with a eucalyptus extract, Eucalyptus grandis, and another one with a solvent were placed in the foraging arena of N. corniger nests under laboratory conditions. The extracts used were from weathered or unweathered wood. During the second experiment, two tests were performed using eucalyptus wood. First, a piece of unweathered wood was impregnated with an extract of weathered wood (treatment) or solvent (control). In the second test, a piece of weathered wood was impregnated with an extract of unweathered wood (treatment) and another one with solvent (control). At the end of the tests, the number of termite recruitment on each substrate was quantified. Filter paper recruited more termites when treated with unweathered wood extracts or with extracts of weathered wood than when impregnated with the solvent. Unweathered wood treated with extracts of weathered wood recruited more termites than the control. However, weathered wood impregnated with extracts of unweathered wood recruited similar numbers of termites as the same wood impregnated with the solvent. It was verified that chemicals from weathered or unweathered wood increased the foraging activity of N. corniger in neutral substrates, but only chemicals from weathered wood altered the attraction of N. corniger to eucalyptus wood. 相似文献
10.
H. Militz S. Schaffert B. C. Peters C. J. Fitzgerald 《Wood Science and Technology》2011,45(3):547-557
Four field trials were conducted with wood modified with dimethyloldihydroxy-ethyleneurea (DMDHEU) in contact with subterranean
termites. Trials 1 to 3 were conducted with Coptotermes acinaciformis (Froggatt); 1 and 2 in south-east Queensland, and 3 in northern Queensland, Australia. Trial 4 was conducted in northern
Queensland with Mastotermes darwiniensis (Froggatt). Four timber species (Scots pine, beech, Slash pine and Spotted gum) and two levels (1.3 M and 2.3 M) of DMDHEU
were used. The tests were validated. DMDHEU successfully prevented damage by C.
acinaciformis in south-east Queensland, but not in northern Queensland. It also did not protect the wood against M.
darwiniensis. Except for beech in trial 4, DMDHEU led to reduced mass losses caused by termite attack compared to the unmodified feeder
stakes. Slash pine (in trials 1 and 3) and Spotted gum (in trial 1) presented low mass losses. Modification of Scots pine
was more effective against termite damage than the modification of beech. 相似文献
11.
12.
The formation of insoluble metaborates in wood was investigated by impregnating the wood with borax and metallic salts, after which their properties (e.g., leachability in running water and biological resistance) were evaluated. The solubility of three metaborates in acidic solutions was also evaluated. Double-diffusion treatment was carried out to form the precipitates of metaborates in sapwood specimens of Japanese cedar (Cryptomeria japonica) at room temperature. Water-saturated wood specimens were first impregnated by a saturated borax solution and then diffuse-penetrated with Zn2+, Ca2+, or Pb2+ solution. The precipitates of the three metaborates in the wood proved to be insoluble or hardly soluble in water by the leaching test. With the decay test using a brown-rot fungus (Fomitopsis palustris) and a white-rot fungus (Trametes versicolor) and with the termite test using a virulent subterranean termite (Coptotermes formosanus), the metaborate-treated woods showed generally good decay and termite resistance with negligible mass loss of the specimens. Particularly, the lead metaborate formed in the wood provided superb biological resistance against decay and termite attacks. In addition, the precipitates of these metaborates were found to be soluble in acidic solution, suggesting a way to remove these chemicals from wood when disposing of waste materials. 相似文献
13.
Yoshiyuki Yanase Masahiro Miura Yoshihisa Fujii Shogo Okumura Tsuyoshi Yoshimura 《Journal of Wood Science》2013,59(3):243-248
A gas detection apparatus equipped with a semiconductor gas sensor was employed for qualitative and quantitative measurement of hydrogen and methane emitted by termites. A gas sample of 2.5 ml was injected into the semiconductor gas sensor through the gas detection apparatus, and the maximum voltage of the sensor was converted into gas concentration. The gas samples were collected from three distinct experiments: (1) five combinations of workers and soldiers of Coptotermes formosanus with and without a wood specimen; (2) C. formosanus under six temperature conditions; and (3) four different termite species, C. formosanus, Reticulitermes speratus, Incisitermes minor, and Zootermopsis nevadensis. The hydrogen and methane concentrations increased with an increase in the number of termites. Concentrations were higher in samples with a wood specimen than without it. Both hydrogen and methane concentrations were the highest for the samples at 35 °C and were lowest at 15 and 5 °C. The concentrations were very low at 45 °C because all the termites had died in a few hours. The concentrations of hydrogen and methane were highest for Z. nevadensis, the dampwood termite, among the four species, and no methane was detected for I. minor, the drywood termite, at 28 °C and 75 % RH. 相似文献
14.
《Wood material science & engineering》2013,8(1):1-3
Abstract Development in surface mould growth on painted/unpainted wooden claddings and acting climatic factors were investigated over a period of 3 years. Eight wood substrates, including modified, preservative-treated and untreated wood, were tested in combination with three types of paint: (1) water-borne alkyd modified acrylic paint without fungicide; (2) solvent-borne alkyd paint without fungicide; and (3) ICP (internal comparison product). One set of samples was exposed unpainted. The samples were tested according to a modified version of EN 927-3. A logistic regression model was fitted to the data. The degree of mould growth varied with exposure time, coating typology, wood substrate, temperature and relative humidity. Exposure time and coating typology contributed most to the model. After 3 years of outdoor exposure unpainted panels and panels coated with solvent-borne paint without fungicide had more mould growth than panels coated with ICP and water-borne paint without fungicide. Unpainted oil/copper–organic preservative-treated claddings had higher resistance to mould growth than other unpainted wood substrates. Coated untreated pine and coated acetylated pine were more susceptible to mould growth than other coated wooden substrates. 相似文献
15.
Survival and development of the dry-wood termite Cryptotermes brevis (Walker) in Berlin
The infestation of museum material and furniture in a private home in Berlin by the dry-wood termiteC. brevis is described. In spite of unfavourable climatic conditions the termites could - in the first case - survive and develop for more than 5 years. Other termite introductions, ecology and economic importance of dry-wood termites are mentioned. 相似文献
16.
Modelling mould growth on coated modified and unmodified wood substrates exposed outdoors 总被引：2，自引：0，他引：2
Mould growth on coated wood is today a genuine challenge for house owners. Environmentally sound wooden facades with long
service lives and acceptable appearance are desired. The objective in this study was to investigate the accumulated mould
growth on 13 different wood substrates with 3 surface coating systems by identifying the factors that contribute to the variation
and to predict future performance. A generalized linear mixed model was fit to the data with the analysis showing that coating
and exposure time both had highly significant influences on mould growth. Further, wood substrate was significant, but comparatively
less than coating and exposure time. A smaller coefficient for mould coverage in the beginning of the exposure period gave
the panels with one of the coating systems, BAP, a delay in mould growth, and the extrapolated values for years 6–12 indicate
a longer aesthetic service life than panels with the two other coating systems. Coated heartwood as wood type was less susceptible
to mould growth than coated mixed wood and coated sapwood. Acetylated pine as wood substrate and aspen as wood species had
lower resistance to mould growth than the other wood substrates and wood species, respectively. 相似文献
17.
This study investigated the suitability of the non-destructive vibration-impulse excitation technique to assess the attack of preservative-treated wood in contact with the ground. Small stakes (10×5×100 mm3) of treated and untreated Scots pine sapwood were exposed to decay in laboratory-scale terrestrial ecosystems. Different soils were used to prove the influence of different types of wood destroying micro-organisms. Wood decay was monitored periodically for one year by determining mass losses and changes in dynamic modulus of elasticity. The results show a large variability in resistance against attacking fungi, depending on wood preservative and soil type. The non-destructive approach using the dynamic modulus of elasticity proved to be a good and sensitive tool for assessing the attack of stakes in laboratory soil testing. 相似文献
18.
柳州市园林树木及城市建筑白蚁危害调查及防治 总被引：1，自引：0，他引：1
柳州市城区危害园林树木的白蚁有3科4属4种,危害房屋建筑的白蚁有1科1属1种。调查23种园林树木中,有18种树木受到白蚁的危害,占78.26%,树木受害株率21.35%,严重受害株率4.16%;调查3 694家住户中,有861户受到白蚁的侵害,占23.31%,危害程度16.44%。台湾乳白蚁Coptotermes formosanus Shiraki是危害城区园林树木及房屋建筑的优势种,在272株受害树木中,有185株受台湾乳白蚁危害,在861户受害房屋建筑中,全部是受台湾乳白蚁危害。阴香、樟树、大叶桉、小叶桉、桃树等园林树木和房屋建筑内的木地板、墙裙、门、窗等木构件受到白蚁危害最为严重,建设健康"森林城市"必须同步抓好园林树木及房屋建筑白蚁防治。 相似文献
19.
Ai Fujita Masaru Hojo Tetsuo Aoyagi Yoshinobu Hayashi Gaku Arakawa Gaku Tokuda Hirofumi Watanabe 《Journal of Wood Science》2010,56(3):222-226
Wood-feeding termites have evolved an efficient cellulose-decomposing system. The termite has two independent cellulose-digesting
systems: one in the midgut and the other in the hindgut. Because the digestion system in the midgut should be the sole source
of soluble sugars for the host termite, the details of the decomposition of wood particles in the midgut were clarified in
one of the most common pest species, Coptotermes formosanus. The spatial distribution of cellulase in the midgut was found by immunohistochemistry, and the amount of endogenous cellulases
and the volume of the endoperitrophic space were determined. The size of wood particles in the foregut and the midgut were
compared. The results showed that one of the characteristics of wood degradation by termites is the mechanical grinding of
food by the mandibles and the cuticular apparatus of the foregut. This process greatly increases the surface area of the substrates.
Extremely high concentrations of cellulase attack the ground-up wood in the midgut, and the glucose produced is removed quickly
through the peritrophic membrane. 相似文献
20.
为了筛选出高效、低毒、低残毒,符合环保要求的白蚁防治药剂,从目前国际上开发的新型白蚁防治药剂中,选用5类有代表性的药剂及复配制剂进行速丰桉新造林地白蚁防治田间试验,结果表明:5%阿维菌素可湿性粉剂、50%福美双可湿性粉剂、2.5%溴氰菊酯乳油、40%毒死蜱乳油、22%甲维氟铃脲可湿性粉剂及复配药剂在林间防治效果均达70%以上。其中,生物制剂5%阿维菌素可湿性粉剂和复配药剂防治效果达85%以上,可以代替氯丹、灭蚁灵和毒死蜱在白蚁防治中使用。同时,阿维菌素对环境友好,在林木白蚁防治中有较好的应用前景。 相似文献