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1.
Application of near-infrared spectroscopy to wood discrimination   总被引：4，自引：0，他引：4  
 This study deals with a new nondestructive discriminant analysis by which wood can be classified on the basis of a combination of near-infrared (NIR) spectroscopy and Mahalanobis' generalized distance. Its accuracy and reasonability were examined for wood samples with various moisture contents ranging from oven-dried to a fully saturated free water state. In a discriminant analysis employing second derivative spectra, each wood group was well distinguished. Mahalanobis' generalized distances between softwoods are relatively independent of analytical pattern, whereas the distances between hardwoods are large for easy classification. There may be two reasons for selecting a wavelength: (1) when the chemical component of wood substance relates to the discriminant analysis; and (2) when the difference in moisture content with wood species relates to them. When we correctly construct the database of NIR spectra, confirming the purpose of the analysis, suitable wood discrimination should be possible. Received: January 23, 2002 / Accepted: March 15, 2002 Acknowledgment The authors sincerely thank the Tanabe Southeast Asia Nations Friendship Foundation for financial support. Part of this report was presented at the 51nd Annual Meeting of the Japan Wood Research Society, 2001 Correspondence to:S. Tsuchikawa  相似文献   

2.
 The fundamental in-plane shear properties were investigated for the wood-based sandwich panel of plywood-overlaid low-density fiberboard (SW) manufactured at a pilot scale to develop it as a shear wall. The shear test method using tie-rods standardized for shear walls was applied to SW with dimensions of 260 mm square and 96 mm thick as a small shear wall and to plywood (PW) and thick low-density fiberboard (FB). The shear modulus and shear strength of PW, FB, and SW were determined. To measure the shear deformation angle, a displacement meter and strain-gauge were used. The shear moduli of PW (0.68 g/cm3) and FB (0.25–0.35 g/cm3) were 460 and 21–58 MPa/rad, respectively. The shear modulus of SW as a composite was analyzed. Some experimental models of SW were proposed (i.e., rigid-α, rigid-β, flexible, and semirigid models). The shear modulus of SW (0.35–0.40 g/cm3) evaluated based on the rigid-α and semirigid models were 73–89 and 109–125 MPa/rad, respectively. The theoretical shear modulus of SW was calculated to be 110–129 MPa/rad. Received: May 9, 2001 / Accepted: June 26, 2002 RID="*" ID="*" Part of this report was presented at the 50th Annual Meeting of the Japan Wood Research Society, Kyoto, Japan, April 2000; and the 5th Pacific Rim Bio-Based Composite Symposium, Canberra, Australia, December 2000 Acknowledgments The authors express our deep gratitude to Mr. Noritoshi Sawada (Hokushin Co.), Dr. Wong Cheng, and their cooperative members for their expert technical support for the preparation of manufacturing the thick fiberboard and sandwich panel. We are grateful also to Drs. Min Zhang, Kenji Umemura, Wong Ee Ding, and Guangping Han for their great help and advice in manufacturing the thick panels. The authors are grateful to Hokushin Co. for the fiber and resin and to Ishinomaki Gouhan Co. for the plywood. We thank Mr. Makoto Nakatani for his expert assistance when preparing the specimens for the shear test. Funding provided by the Research Fellowship of the Japan Society for the Promotion of Science for Young Scientists as a JSPS Research Fellow is also gratefully acknowledged.  相似文献   

3.
 Supercritical carbon dioxide (SC-CO2) was tested for its potential as a carrier solvent for preservative treatment of solid wood and wood-based composites. A preliminary trial showed that the treatability of solid wood varied with its original permeability and that the SC-CO2 treatment was not promising for refractory timber species such a Larix leptolepis Gordon. In contrast, 3-iodo-2-propynyl butylcarbamate (IPBC)/SC-CO2 treatment resulted in enhanced decay resistance without any detrimental physical or cosmetic damage in all structural-use wood-based composites tested: medium density fiberboard, hardwood plywood, softwood plywood, particleboard, and oriented strand board (OSB). Further trials under various treatment conditions [25°C/7.85 MPa (80 kgf/cm2), 35°C/7.85 MPa, 45°C/7.85 MPa, 35°C/11.77 MPa (120 kgf/cm2), and 45°C/11.77 MPa] indicated that although small changes in the weight and thickness of the treated materials were noted the strength properties were not adversely affected, except for a few cases of softwood plywood and oriented strand board. The results of this study clearly indicated that the treatment condition allowed SC-CO2 to transport IPBC into wood-based composites, and the optimum treatment condition seemed to vary with the type of wood-based composite. Received: October 24, 2001 / Accepted: February 15, 2002 Part of this work was presented at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001; and the 32nd Annual Meeting of the International Research Group on Wood Preservation, Nara, May 2001 Correspondence to:M. Muin  相似文献   

4.
 Some tropical fast-growing woods were converted to edge-jointed lumber, and their fire-retardant properties due to chemical coating were evaluated using cone calorimetry and a standard fire test. The woods used were Indonesian and Malaysian albizia and gmelina plantation trees, with Japanese hinoki as a reference. The lumber was coated with 100 g/m2 of trimethylol melamine phosphoric acid in a 25% aqueous solution. The treated and untreated lumber was tested in a laboratory-scale exposure furnace in accordance with JIS A 1304 and the cone calorimeter test with heat flux of 40 kW/m2 following the ISO 5660. Results showed that fire endurance of all lumber was enhanced by the treatment. The fire-retardant properties were improved with increasing surface density. Though a similar trend was seen, the fire-retardant properties of the lumber revealed by the cone calorimeter test were inferior to those seen with standard fire test. Addition of thermocouples to the cone calorimeter allowed us to obtain information on the critical temperature (260°C) and charring temperature (300°C) of the lumber. Received: January 23, 2002 / Accepted: July 15, 2002 Acknowledgment The authors thank Dr. Shigehisa Ishihara, Professor Emeritus of the Wood Research Institute, Kyoto University for his suggestions about this experiment.  相似文献   

5.
 Spatial distribution of sporocarps of Suillus pictus A.H. Smith and Thiers was studied in a plot of 6 × 12 m in size established in a stand of Pinus koraiensis Sieb. et Zucc. in Kyoto, Japan for 4 years, and the biomass of mycorrhizas was examined in the last year. S. pictus was dominant in both sporocarp and ectomycorrhizal community in the study plot. The number of S. pictus sporocarps ranged from 0.94 to 1.26 m−2 (surface area) in the study plot and did not vary very much during the study period. Sporocarps of S. pictus occurred in clumps and the distributions of clumps were generally random. As the spots of sporocarp occurrence changed gradually from year to year, the distributions of sporocarps that occurred successively in 2-year periods overlapped, especially when analyzed in 9-m2 unit size using the m * –m method. Mycorrhizas of S. pictus were distributed in more subplots than its sporocarps. Distribution of mycorrhizas and sporocarps of S. pictus generally overlapped well. The biomass of mycorrhizas and mycelia in the mycorrhizas of S. pictus was estimated at 15.5 g DW m−2 and 6.2 g DW m−2 (surface area) in this plot, respectively. The biomass of mycorrhizas and mycelia in the mycorrhizas supporting the production of one sporocarp (average dry weight was 0.86 g) of S. pictus was evaluated as about 16.4 and 7.3 g DW, respectively, in this plot. Received: December 20, 2001 / Accepted: August 12, 2002 Acknowledgments We thank Dr. T. Furuno, Mr. N. Kato, and Dr. I. Nakai for their help in preparing the study plot and collecting sporocarps, and Prof. K. Yokoyama for the identification of sporocarps. Thanks are also due to Dr. E. Kuno for his suggestion about analysis. Correspondence to:J. Kikuchi  相似文献   

6.
 The relations among internal temperature, internal pressure, and moisture content distribution in sugi square lumber during high-frequency (HF) heating were determined to clarify the mechanism of water movement during the combination of HF heating and hot air exposure. Green sugi square lumbers were subjected to HF heating under atmospheric pressure. The water movement and pathways in the lumber during HF heating were also investigated. Results showed that internal pressure is the driving force of water movement. HF heating causes a rise in the internal temperature and internal pressure in sugi square lumber. Ordinarily, water in lumber evaporates from the surfaces of lumber during hot air drying. However, with HF heating the internal pressure is generated by the increased temperature, and liquid water is driven not only parallel to the grain but also perpendicular to the grain of the lumber. The ratio of the amount of liquid flow in the parallel and perpendicular directions ranged from 2 : 3 to 1 : 3. When the movement of water in the lumber was traced with a 0.5% aqueous solution of acid fuchsin, water was found to move through the lumber in the longitudinal direction and then flow in a direction perpendicular to the grain or in the radial and tangential directions. Received: June 15, 2001 / Accepted: February 8, 2002 Acknowledgment The authors thank Dr. O.R. Pulido, Institute of Wood Technology, Akita Prefectural University, for discussions and for proofreading this paper. Part of this research was presented at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001 Correspondence to:Y. Kawai  相似文献   

7.
 To establish a sampling procedure for estimating the density of bamboo galls induced by Aiolomorphus rhopaloides Walker (Hymenoptera: Eurytomidae) in a stand of bamboo Phyllostachys heterocycla (Carr. Mitf.) (Monocotyledoneae: Gramineae), 5–12 bamboo culms were cut at random in late March of each year during 1998–2001 just before gall-maker emergence. The number of galls on the branches of each bamboo culm was counted. The spatial patterns of the galls on the culms in the stand and on the branches within each culm were measured by Iwao's patchiness regression. Galls were distributed contagiously both on culms and on branches. Current bamboo culms that emerged the previous summer did not require sampling because no galls were observed on them. Except for this, there was no difference in gall density on young and old culms, suggesting that it is not necessary to distinguish them. There were few (<4%) galls above 6 m height during the 4 years. There was no significant difference in gall density up to 4 m and above 4 m, suggesting that branches up to 4 m can be sampled with confidence. Kuno's two-stage sampling method at different precision levels showed that the number of culms to be sampled varied with gall density. For example, at mean density m = 1.0 per branch when the number of sampled branches per culm is 10, a total of 24 culms is required to estimate gall number at a precision level of D = 0.2, where D is the ratio of standard error to mean. Received: July 10, 2002 / Accepted: November 25, 2002 Acknowledgments I thank Dr. K. Kamijo for insect identification. Thanks are also due to the members of the Laboratory of Forest Protection for their kind help with the fieldwork. This study was supported in part by a Grant-in-Aid for Scientific Research (No. 11460068) from the Ministry of Education, Culture, Sports, Science and Technology, Japan.  相似文献   

8.
 To isolate and identify the cement-hardening inhibitory components of keyaki (Japanese zelkova, Zelkova serrata Makino), methanol extractives containing inhibitory components were fractionated by successive organic solvent extraction and column chromatography, and the inhibition of these fractions was determined. Spectroscopic analysis of one isolated compound identified it to be keyakinin with the C-glucoside structure of a flavonol. According to the inhibitory indices, the compound was found to be the main cement-hardening inhibitory component of keyaki. Extraction of keyaki with hot water or a blend of keyaki with up to 30% hinoki as a suitable species diminished the cement-hardening inhibition of wood-cement board to a great extent, suggesting that such treatments are economical countermeasures to this inhibition. Received: April 17, 2002 / Accepted: June 24, 2002 Acknowledgments The authors thank Dr. W. Nagadomi, Nichiha Co., for providing Japanese zelkova wood. This research was conducted with the support of the TOSTEM Foundation for Construction Materials Industry Promotion.  相似文献   

9.
 Cuttings from older trees of the Dipterocarpaceae generally lose their ability to root. However, branches in a canopy of adult dipterocarps are a possible source of cuttings because they show juvenile characteristics in architecture due to “adaptive reiteration”, suggesting physiological rejuvenation. Effects of resource plant size on the rooting of cuttings and the possibility of using cuttings from reiterated branches of adult trees were studied for Dryobalanops lanceolata, an emergent dipterocarp species. A cutting experiment with non-mist propagators was conducted for cuttings collected from resource plants of four different size classes: <2 m, 2–5 m, 8–15 m, and 70 m in height. The smallest size class included two different age classes: <2 and >2 years old. Cuttings from the tallest resource plant were collected from reiterated branches. Rooting percentage was negatively correlated with resource plant size: 77–78% for resource plants <2 m, 63% for 2–5 m, 36% for 8–15 m, and 0% for 70 m. Rooting percentages of cuttings collected from different individuals were not different for the 2–5 m tall class, while they were significantly different for the 8–15 m tall class. Resource plant size was negatively correlated with the number of roots for rooted cuttings. No significant relationship was observed between resource plant size and mean length of each root, total root length or total root dry weight for rooted cuttings. The results suggest the possibility of collecting cuttings from relatively large resource plants up to 15 m tall and >20 years old if we chose good individuals for resource plants. The results, however, show the difficulty in using reiterated branches of adult trees as a source of cuttings for D. lanceolata. Received: October 15, 2001 / Accepted: November 11, 2002 Acknowledgments We express our sincere thanks to Dr. S. Tamura, Dr. K. Ogino, and Mr. A.A. Hamid for their kind support. The tree tower was constructed in a cooperative project between Japan and Sarawak supported by the Ministry of Education, Culture, Sports, Science and Technology, Japan (Grant NP0201). The cutting experiment was partly funded by the Nippon Life Insurance Foundation and the Japan Society for the Promotion of Science (JSPS-RFTF96R16001). Correspondence to:A. Itoh  相似文献   

10.
 The effects of pasture fertilization frequency and two vertical positions in the stem on elasticity and strength parameters during static bending (modulus of elasticity, stress at proportional limit, modulus of rupture) of Pinus radiata wood growing in a silvopastoral system were evaluated. Twenty-seven trees were selected randomly from three silvopastoral trials established at Tanumé Experimental Center (34°9′–34°15′ S; 72°53′–72°59′ W). The results indicated that pasture fertilization frequency had no significant effect on the physical and mechanical parameters evaluated. However, the vertical position in the stem did have a significant effect on stress at the proportional limit and on the modulus of rupture due to different average values for the annual ring width and nominal density found in the specimens obtained from logs at two different heights of the stem. Received: February 20, 2002 / Accepted: June 5, 2002 Acknowledgments The authors thank the following institutions and people for their support: CONAF, VI Region; Dr. Rolando Rodríguez, CONAF VIII Region; Cesar Cabrera, Forestry Engineer, CONAF VI Region; Osvaldo Herrera, Director of Experimental Center “Tanumé”; Dr. Manuel Sánchez, Faculty of Forestry Sciences, University of Concepción; Dr. Glenn Hofmann, Faculty of Physics and Mathematics, University of Concepción; Alex Opazo, M.Sc.(C), Faculty of Forestry Sciences, University of Concepción; Staff of Experimental Center “Tanumé”. Correspondence to:M.H.R. Vidal  相似文献   

11.
 We evaluated the protective effects of floor cover against soil erosion in three types of forest located on steep slopes under a humid climate: 22- and 34-year-old Chamaecyparis obtusa (hinoki), 34-year-old Cryptomeria japonica (sugi), and 62-year-old Pinus densiflora (red pine) stands. We measured sediment transport rates (sediment mass passing through one meter of contour width per millimeter of rainfall), using sediment traps, before and after removing floor cover. Raindrop splash erosion was dominant in the experimental stands. Floor cover percentage (FCP) during the preremoval stage varied from 50% to 100% among the four stands, and sediment transport rates ranged from 0.0079 to 1.7 g m−1 mm−1. The rates increased to 1.5–5.6 g m−1 mm−1 immediately after removing floor cover, and remained high throughout the experiment. The presence of physical cover near the ground has a crucial effect on sediment transport on forested slopes. The protective effect ratio (the ratio of the sediment transport rate in a control plot to that in the removal plot) in a young hinoki stand, in which the FCP decreased markedly, was 0.3 at most, which is close to the rate for bare ground. The protective effect ratio in the red pine stand was ≤0.003. We concluded that the protective effect of floor cover in undisturbed forests in Japan differs by over two orders of magnitude, based on comparisons with previous studies. Received: March 11, 2002 / Accepted: August 16, 2002 Present address: Department of Forest Site Environment, Forestry and Forest Products Research Institute, Ibaraki 305-8687 Japan Tel. +81-298-73-3211; Fax +81-298-74-3720 e-mail: miura@affrc.go.jp Present address: Department of Forest Site Environment, Forestry and Forest Products Research Institute, Ibaraki 305-8687 Japan Tel. +81-298-73-3211; Fax +81-298-74-3720 e-mail: miura@affrc.go.jp Acknowledgments This study was supported by the Research Council of the Ministry of Agriculture, Forestry, and Fisheries, of Japan. We thank H. Ujihara, S. Ujihara, and M. Ogasawara in Otoyo, Kochi, who provided the experimental stands used in this study. We also thank K. Hirai, S. Kuramoto, E. Kodani, and the rest of the staff at the Shikoku Research Center, Forestry and Forest Products Research Institute, for their help in conducting the experiments. Correspondence to:S. Miura  相似文献   

12.
 The morphological features and dietary functional components of two strains (FPF-13 and Oninome-B) of Pholiota adiposa (numerisugitake mushroom) grown on artificial bed blocks were examined. The components examined were chitin, mannitol, trehalose, guanosine 5′-monophosphate, ergosterol, and β-glucan. There was a significant difference in the external shape of the two strains. However, the differences in the contents of functional components between the two strains, as well as between the pilei and stipes of the strains, were small. In both strains the trehalose content was much higher than the mannitol content, in contrast to those of Lentinula edodes. From a commercial point of view, Oninome-B has a clear advantage over other strains of P. adiposa owing to its less removable scale. Received: May 15, 2002 / Accepted: June 10, 2002 Acknowledgment The authors thank Dr. F. Eguchi (Takasaki University of Health and Welfare) for his technical advice on the β-glucan analysis. Part of this report was presented at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001 Correspondence to:K. Shimizu  相似文献   

13.
 Cacao (Theobroma cacao L.) hulls were physically separated into vascular bundles (VBs) and nonvascular bundles (NVBs) to investigate their chemical compositions and the structural features of abundant polyphenolic compounds. Glucose content was determined to be 21.4% for VBs and 17.5% for NVBs, together with xylose content as 13.1% for VBs and 2.8% for NVBs. In addition, uronic acid in NVBs (12.9%) was much higher than that in VBs (5.2%). The content of total (poly)phenolic compounds (35.9%–39.1%) quantified as Klason residues (KRs) and acid-soluble phenolic compounds (ASPs) were similar in both cell types, although there were great differences in the structural characteris-tics of polyphenolic compounds. The pyrogram of VBs clearly showed high intensities of guaiacol and 4-vinylguaiacol together with low intensities of catechol and 4-methylcatechol. On the other hand, that of the NVBs showed opposite trends. These results were confirmed by alkaline nitrobenzene oxidation based on total yields of vanillin and syringaldehyde. Therefore, the accumulation of various polyphenolic compounds in cacao hulls relies strongly on the cell type and is correlated with the development of a secondary wall. Received: October 9, 2001 / Accepted: April 15, 2002 Present address: Institute of Biological Chemistry, Washington State University, Pullman, WA 99164-6340, USA Acknowledgments This project was partially supported financially by a Grant-in-Aid from the Ministry of Education, Culture, Sports, Science and Technology (no. 13375007). We thank Dr. Hadi S. Arifin, Faculty of Agriculture, Bogor Agricultural University, Indonesia, for collecting cacao fruits at the Rajamandala Cacao Plantation at Rajamandala in West Java. Correspondence to:K. Iiyama  相似文献   

14.
 Taiwania (Taiwania cryptomerioides Hayata), native to Taiwan, is one of the most economically important tree species grown there. In this article we summarize the current results of phytochemistry and bioactivity of Taiwania extracts, including antifungal, antitermite, antibacterial, and antimite activities as well as cytotoxicity against three tumor cells. The resources of Taiwania are also addressed. Received: January 23, 2002 / Accepted: March 8, 2002 Acknowledgment The authors thank the National Science Council of R.O.C. for financial support (NSC-90-2313-B-002-344). Correspondence to:S.-T. Chang  相似文献   

15.
 Experimental results were studied to determine the relationships between positioning precision of a differential global positioning system (DGPS) and forest type, antenna height, and season, and to clarify the relationship between sampling number and the convergence of positioning precision. Observation was carried out for 24 h. Mean circular area probability (CEP95) was 2.80 m for deciduous broadleaved trees, and 4.99 m for conifers. The mean CEP95 taken at 7 m height (3.14 m) was higher than that at 1 m height (3.92 m) at all sites. The mean CEP95 taken during the defoliation season (2.65 m) was slightly better than during the foliation season (2.96 m). There were significant differences between forest types (P < 0.001) and antenna heights (P < 0.05). Positioning precision was not noticeably improved if the sampling number was around ten or less. A sampling number of 100–1000 or more is required before substantial improvements can be expected. As long as high positioning precision is not required, it is acceptable to use 2D & 3D modes and relatively few samples to take measurements. Received: April 24, 2002 / Accepted: October 10, 2002 Correspondence to:I. Sawaguchi  相似文献   

16.
 Kenaf (Hibiscus cannabinus) plants are widely known for their contribution to the global and regional environment because of their ability to fix CO2. On the other hand, some scientists have doubts about CO2 fixation by kenaf and have misgivings about the effect of kenaf on the ecosystem. We have characterized the structural characteristics of cell walls of bast fibers, cores, roots, and leaves of kenaf during the maturation of plants and investigated the rate of photosynthesis. During maturation of the kenaf plant the cellulose (bast fiber 52–59%, core 44–46%) and lignin (bast fiber 9.3–13.2%, core 18.3–23.2%) contents increased significantly. The aromatic composition of the lignin of bast fiber was significantly different from that of the core lignin and of other plants. The lignin of bast fiber appears similar to pure syringyl lignin. Fixation of CO2 by kenaf plants and their contribution to the global environment are discussed. A significatly high rate of photosynthesis of kenaf plants was observed compared to that of woody plants in Japan, but the amount of CO2 fixation depends on the characteristics of the plantation. If the kenaf was planted in high density, about twice as much CO2 was fixed as was fixed by trees in a tropical rain forest. Received: April 22, 2002 / Accepted: July 24, 2002 Acknowledgments This project was supported by the Science and Technology Agency (STA) fellowship of the Japan International Science and Technology Exchange Center (JISTEC), which has been successfully applied by Dr. Shuji Hosoya, Forestry and Forest Products Research Institute. We thank Dr. Toshio Sumizono and Mr. Masao Sakurai, Forestry and Forest Products Research Institute, for their kind help in determining the rate of photosynthesis and cultivating the kenaf plants, respectively. We also express our appreciation to Dr. Quang Hung Le, College of Agriculture and Forestry, Ho Chi Minh City, Vietnam for offering information about the cultivation of kenaf at Thu Duc District, Ho Chi Minh City.  相似文献   

17.
 Increases in stand volume with some currently introduced provenances of Acacia mangium: Papua New Guinea (PNG) and Far North Queensland (FNQ), were projected based on their superiorities in 3-year height growth in seedling seed orchards using the growth model developed for unthinned plantation for pulp and paper production in South Sumatra, Indonesia. The height growth of these provenances was better than that of the local selections from Subanjeriji by 10%–15% at 3 years old and these percentage superiorities would be expected to remain at around 9%–14% until the 8-year rotation. This amount of increase would result in a 7%–10% increase in basal area and hence it would produce a 17%–26% increase in stand volume at rotation age when compared with the Subanjeriji seed source that was being widely used for the plantation establishment of A. mangium in Indonesia. Received: July 24, 2002 / Accepted: December 3, 2002 Acknowledgments The authors thank Mr. Hardjono, the director of plantation establishment at PT Musi Hutan Persada for his permission to use data of permanent plots for the growth modeling of A. mangium. The authors are grateful to the staff at PT Musi Hutan Persada, Research and Development Center for Biotechnology and Forest Tree Improvement, Japan International Cooperation Agency for their implementations of the study. Our thanks are also due to Dr. Yoshida, associate professor at Kyushu University, for his advice on developing the growth modeling work. Correspondence to:S. Kurinobu  相似文献   

18.
 Adhesion problems sometimes occur during the production of laminated wood products. To minimize such quality problems, there is a need for a nondestructive test that can provide continuous control of the process and the product. This study presents results from measurements performed to evaluate the potential of pulse thermography as a method to detect glue deficiency in laminated wood. Defect depth, defect size, and degree of glue deficiency have been varied. The surface layer was made of merbau (Intsia bijuga) and the substrate of Scots pine (Pinus silvestris). The results showed that pulse thermography is a promising tool for detecting glue deficiency underneath the thin laminated wood surface layers, mainly because of the short inspection time. Lack of glue with a minimum thermal defect size of 3 was detectable (thermal defect size is defined as the quotient of defect size and defect depth). The penetration depth was 1.0 mm and the highest contrast, 0.62°C, was achieved for one of the largest defects (24 mm) below the thinnest (0.5 mm) surface layer after 1 second. Starved glue joints showed about half the contrast compared to areas with total lack of glue. Received: April 24, 2002 / Accepted: July 26, 2002 Acknowledgments We gratefully acknowledge the support of this work from the Knowledge Foundation and The Swedish Wood Association.  相似文献   

19.
    
 The chemical conversion of phenolized sulfuric acid lignin (P-SAL), prepared from sulfuric acid lignin (SAL) by phenolation with sulfuric acid catalyst, to novel cationic surfactant was investigated. To elucidate the chemical reactivity of the P-SAL to a Mannich reaction, 1-guaiacyl-1-p-hydroxyphenylethane (I) as a simple phenolized sulfuric acid lignin model compound was reacted with dimethylamine and formaldehyde. Quantitative analysis of the products by gas-liquid chromatography suggested that the p-hydroxyphenyl nucleus was more reactive than the guaiacyl nucleus. The Mannich reaction of SAL with dimethylamine did not yield a soluble cationic surfactant, but P-SAL produced water-soluble cationic surfactant in a quantitative yield. The Mannich reaction products (MP-SAL) of P-SAL had 1,3-dimethylaminomethyl groups/C9-C6. The results of the surface tension measurements showed that the decrease in surface tension of MP-SAL was much larger than that of lignosulfonate as a commercial surfactant from lignin. Received: February 13, 2002 / Accepted: June 12, 2002 Acknowledgments The authors thank Nippon Paper Industries Co. and Lion Corp. for providing the commercial products and Dr. K. Aoi (Graduate School of Bioagricultural Sciences, Nagoya University, Japan) for advising us on the measurement of surface tension. This research was conducted with the support of a Grant-in-Aid for Scientific Research (11460079) from the Ministry of Education, Culture, Sports, Science and Technology of Japan. Part of this report was presented at the 52nd Annual Meeting of the Japan Wood Research Society, Gifu, April 2002 Correspondence to:Y. Matsushita  相似文献   

20.
 The species richness of trees, shrubs and climbing plants was investigated in 41 sugi (Cryptomeria japonica D. Don) plantations of different stand age and area in southern Kyushu, southwestern Japan. Altogether 174 species were found, of which 145 infrequent species were selected for analysis. Two groups were extracted from the species list according to their occurrence in older (49 spp.) or younger (28 spp.) stands, the latter containing a higher percentage of climbing plants and species with wind-dispersed seeds. In contrast, the older stand group contained major tree components typical of seminatural, evergreen broadleaved forests in the region and was more heavily dependent on stand age, especially for species with gravity- and frugivore-dispersed seeds, showing a gradual increase up to 60 years old. The species richness was less correlated with edge perimeter facing seminatural forests and the years after latest thinning. The juxtaposition of plantation compartments with stands of seminatural forest or other plantations, as well as the compartment's origin as former plantation site or a seminatural stand, had relatively little influence on species richness. However, topographic variation was important in determining the species composition, with valley stands having higher species richness and containing many plants typical of the regional seminatural forests. These results suggest that (1) the major trend of species richness is determined by the presence of old stand type species, (2) topographic variation of species richness remains even after establishment of plantations, and (3) the normal rotation period of sugi plantations (35–40 years) may therefore be too short to conserve the maximum potential species diversity within the working forest. Received: June 4, 2001 / Accepted: August 26, 2002 Acknowledgments We wish to thank the staff of the Miyazaki University Forests for cooperation in the fieldwork. A part of this study was supported by the Grant-in-Aid for Scientific Study from the Ministry of Education, Science and Culture of Japan (no. 09041071 and no. 10460068). Correspondence to:S. Ito  相似文献   

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