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1.
Plant growth regulation effects of triterpenoid saponins 总被引:1,自引:0,他引:1
To investigate structure–activity relations between the sugar chain structures of triterpenoid saponins and their plant growth
regulation effects, several monodesmosidic saponins with betulin as an aglycon were synthesized by chemical and enzymic reactions.
Three triterpenoids (betulin, betulinic acid, oleanolic acid) and synthesized betulin glycosides were submitted to germination
and growth regulation tests on alfalfa seeds. We concluded the following. Betulin had a slight growth inhibitory effect on
alfalfa radicles. Betulin glycosides exhibited stronger effects than betulin, and betulin glycosides with two to four glucose
residues as a sugar moiety had the greatest inhibitory activity. These characteristics of growth inhibitory effects were considerably
different from those of phenolic compounds so far reported. Some betulin glycosides also showed a significant growth regulation
effect on alfalfa hypocotyls. However, hypocotyl growth was less affected than radicle growth for all betulin glycosides.
Among the triterpenoids, betulinic acid had stronger growth inhibitory effects on alfalfa radicles than betulin, suggesting
the importance of the carboxyl group at the C-28 position for the inhibitory effects of lupane-type triterpenoids. On the
other hand, no germination regulation effects on alfalfa seeds were observed for any of the betulin glycosides or triterpenoids
examined.
Received: October 9, 2001 / Accepted: February 15, 2002
Acknowledgments This work was supported in part by a research grant (Development of Highly Functional Materials by Structural Modification
of Carbohydrates) from the Ministry of Agriculture, Forestry, and Fisheries of Japan. We thank Saori Kudo for her assistance
in isolating compounds by chromatography.
Correspondence to:S. Ohara 相似文献
2.
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
3.
Reaction behavior of lignin in supercritical methanol as studied with lignin model compounds 总被引:2,自引:0,他引:2
The reaction behavior and kinetics of lignin model compounds were studied in supercritical methanol with a batch-type supercritical
biomass conversion system. Guaiacol, veratrole, 2,6-dimethoxyphenol, and 1,2,3-trimethoxybenzene were used as model compounds
for aromatic rings in lignin. In addition, 5-5, β-1, β-O-4, and α-O-4 types of dimeric lignin model compounds were used as representatives of linkages in lignin. As a result, aromatic rings
and 5-5 (biphenyl)-type structures were stable in supercritical methanol, and the β-1 linkage was not cleaved in the β-1-type structure but converted rapidly to stilbene. On the other hand, β-ether and α-ether linkages of β-O-4 and α-O-4 lignin model compounds were cleaved rapidly, and these compounds decomposed to some monomeric compounds. Phenolic compounds
were found to be more reactive than nonphenolic compounds. These results indicate that cleavages of ether linkages mainly
contribute to the depolymerization of lignin, whereas condensed linkages such as the 5-5 and β-1 types are not cleaved in supercritical methanol. Therefore, it is suggested that the supercritical methanol treatment effectively
depolymerizes lignin into the lower-molecular-weight products as a methanol-soluble portion mainly by cleavage of the β-ether structure, which is the dominant linkage in lignin.
Received: December 19, 2001 / Accepted: April 30, 2002
Acknowledgments This research has been done under the research program for the development of technologies for establishing an ecosystem
based on recycling in rural villages for the twenty-first century from the Ministry of Agriculture, Forestry and Fisheries,
Japan; by a Grant-in-Aid for Scientific Research (B)(2) (no.12460144, 2001.4–2003.3) from the Ministry of Education, Culture,
Sports, Science and Technology, Japan; and under the research program from Kansai Research Foundation for Technology Promotion,
Japan. The authors thank them for their financial support.
This study was presented in part at the 45th Lignin Symposium, Ehime, Japan, October 2000 and the 52nd Annual Meeting of the
Japan Wood Research Society, Gifu, Japan, April 2002
Correspondence to:S. Saka 相似文献
4.
Somatic embryogenesis in Chamaecyparis pisifera Sieb. et Zucc. was initiated from immature seeds collected from the end of June to early July. Mass propagation through adventitious
shoot bud production from somatic embryo culture on Woody Plant (WP) medium and artificial seed production using sodium alginate
was achieved. A high bud forming index value (25.8) was obtained on medium supplemented with 1 μM 6-benzylaminopurine. The conversion rates from artificial seeds under aseptic and nonaseptic conditions were 60%–100% and
10%–12%, respectively. For germplasm conservation, somatic embryos and embryogenic cells were successfully stored at 4°C (medium-term
storage) and in liquid nitrogen for long-term storage.
Received: December 21, 2001 / Accepted: August 1, 2002
Acknowledgments This work was supported in part by the Japan Science and Technology Corporation and in part by a Grant for Research for the
Future Program from the Japan Society for the Promotion of Science.
Correspondence to:E. Maruyama 相似文献
5.
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
6.
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
7.
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
8.
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
9.
The composition and antitermite activities of nine essential oils from two Melaleuca species, gelam and cajuputi, were compared using gas chromatography–mass spectrometry analysis and bioassays. Gelam oils
were rich in compounds whose boiling points were high, and they were separated into the elemene-rich type and the γ-terpinene- and terpinolene-rich type. Cajuputi oils in this experiment were categorized into three chemotypes according to
their 1,8-cineole content: high, low, none. In the termiticidal activity test, gelam oils were stronger than most cajuputi
oils in the contact condition. The elemene-rich gelam lost its activity in the noncontact condition, whereas another type
of gelam kept its termiticidal activity. The authentic sample of elemene showed the same result as the elemene-rich gelam,
indicating that the termiticidal activity of gelam was caused by at least two types of compound: elemene and “others.” 1,8-Cineole
exhibited the same tendency as elemene, but it was weak. Hence the 1,8-cineole content of cajuputi was irrelevant to termiticidal
activity of samples that exhibited strong activity under both conditions despite their high content. The appearances of gelam
and cajuputi leaves are easily confused, a problem that has not yet been solved. Other scientific methods, such as genetic
analysis, are required to identify gelam. The difference in the compositions and antitermite activities, however, were charified
in this experiment.
Received: November 30, 2001 / Accepted: June 5, 2002
Correspondence to:M. Yatagai 相似文献
10.
E. Shibata 《Journal of Forest Research》2003,8(2):0123-0126
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
11.
Sugi green logs with red or black heartwood were smoke-heated, and the changes in the color of the heartwood after ultraviolet
(UV) (λ = 365 nm) radiation exposure were then observed. After UV radiation exposure, the redness and yellowness increased in both
the red and black heartwoods, whereas the brightness decreased. In the black heartwood, the resulting color turned from yellowish
white to reddish brown. Reddening in black heartwood after exposure to a combination of smoke heating and UV radiation is
thought to be due to a decrease in brightness and an increase in both redness and yellowness. However, the degree of change
in heartwood color by UV radiation exposure was not greatly affected by smoke-heating treatments of various lengths. When
methanol extracts were fractionated and exposed to UV radiation, the yellowness increased in the n-hexane-soluble portion and the redness increased in the acetone-soluble fractions from the n-hexane-insoluble portion. These results suggest that the n-hexane-soluble fraction contains the substances that allow heartwood color to change to yellow after UV radiation exposure,
and the acetone-soluble-fraction from the n-hexane-insoluble portion contains the substances that allow it to change to red.
Received: November 14, 2001 / Accepted: June 3, 2002
Acknowledgment This research was supported in part by a Grant-in-Aid for Scientific Research from the Japan Society for the Promotion of
Science.
This study was presented in part at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001
Correspondence to:N. Yoshizawa 相似文献
12.
Parasitism by parasitoid wasps on the larvae of Epinotia granitalis (Butler), which is a wood-injuring pest in coniferous plantations, was observed for 6 years in two plantation forests of
Chamaecyparis obtusa (Sieb. et Zucc.) Endl. and Cryptomeria japonica (L.f.) D. Don that were adjacent to each other and consisted of trees of almost the same size. E. granitalis larvae were collected from early April to mid-May, then reared in glass bottles, and finally examined to determine whether
or not the larvae had been parasitized. Five species of parasitoids were recorded; two of them were classified in Ichneumonidae,
Campoplex spp. A and B, and others in Braconidae, Iconella repleta Papp, Bassus cingulipes Nees von Esenbeck, and Bracon spp. In all 6 years, parasitism was first observed around 20 April. Species composition of parasitoids differed greatly among
years and between forests. In 1 year in each forest the percentage parasitism increased significantly with the sampling date,
indicating that not all parasitoids attack the same developmental stage of E. granitalis. The mean percentage parasitism per year was significantly higher in the forest of C. obtusa [11.5(%) ± 5.7(SD)] than in the forest of C. japonica (3.0 ± 4.1). These results suggest that the efficiency of parasitoid adults in finding hosts differed between the two forests.
Received: September 20, 2001 / Accepted: August 5, 2002
Acknowledgments We are grateful to Dr. K. Maeto, Shikoku Research Center, Forestry and Forest Products Research Institute, and to Dr. K.
Konishi, National Agricultural Research Center for Hokkaido Region, for identifying parasitoids, and to Dr. T. Miyaura, Forest
Tree Breeding Center, and Dr. H. Kosaka, Forestry and Forest Products Research Institute, for their helpful advice throughout
the study.
Correspondence to:K. Kato 相似文献
13.
An effort was made to develop photocatalytic TiO2 crystallite–activated carbon (TiO2-AC) composites from tetraisopropyl titanate (TPT)-soaked activated carbon in supercritical isopropanol. It was subsequently
found that TPT in supercritical isopropanol could be effectively converted to the anatase form of the TiO2 crystallites. The prepared composites, composed of activated carbon as an adsorbent and the anatase form of TiO2 as a photocatalyst, were evaluated for their adsorption capacity and subsequent photocatalytic activity against formaldehyde,
one of the harmful air pollutants in the environment. As a result, the supercritically treated TiO2–AC composites, particularly at 300°C and 350°C, had much higher formaldehyde-decomposing ability compared to a noncomposite
comprising a simple mixture of activated carbon and TiO2 granules. This indicates that the supercritical treatment can be effective for preparing the photocatalytic composites that
have a high synergetic effect of adsorption and photocatalytic decomposition of formaldehyde for environmental cleaning.
Received: May 18, 2001 / Accepted: March 8, 2002
On leave from Fujian Forestry College, Fujian 353001, P.R. China
Acknowledgments The authors express their sincere thanks to Miss H. Tokoro and Mr. D. Kusdiana for their kind, valuable help and cooperation
and to Dr. H. Miyafuji for SEM observations of samples, all at the Graduate School of Energy Science, Kyoto University.
Correspondence to:S. Saka 相似文献
14.
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
15.
Conditions for cell growth of suspension cultures of Cupressus lusitanica, which has high β-thujaplicin productivity, were studied. The medium that provided the highest growth rate was IS-1 medium (pH 5.5), modified
from Gamborg B5 medium containing 32 mM of total nitrogen. Its NO3-N/NH4-N ratio was 30 : 2. The maximum growth represented a 25-fold increase over the initial biomass on a fresh weight basis after
30 days of culture in this medium. The highest cell growth was obtained with an initial pH of 3.5–5.5, but the pH of the medium
settled to about pH 4.0 from any of the initial pH values in this report. The cells cultured under this condition were able
to produce a high level of β-thujaplicin.
Received: September 7, 2001 / Accepted: May 7, 2002
Present address: Teijin Ltd., Ehime 791-8530, Japan
Present address: Q'SAI Co. Ltd., Fukuoka 811-3422, Japan
Part of this report was presented at the 10th international symposium on wood and pulp chemistry, Yokohama, Japan, June 1999
Correspondence to:K. Fujita 相似文献
16.
A. Itoh T. Yamakura S. Tan J. J. Kendawang H. S. Lee 《Journal of Forest Research》2003,8(2):0117-0121
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
17.
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
18.
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
19.
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
20.
The amounts of CO2 that are absorbed and emitted by forest in a model stand area were determined using two calculation methods, namely the flow
approach and the stock approach for emission trading, to understand the relationships between the cutting age for the highest
profit rate (CAHPR; optimum tree ages to be cut so as to maximize the profit) and (1) the prices of CO2 and (2) the balance between CO2 emission and absorption. The resultant CAHPR differed between these two CO2 accounting methods, which give different tree ages for maximum log volume yield. A rise in CO2 price caused the CAHPR to approach the tree age of maximum log volume in the flow approach method, and to deviate from the
tree age of maximum log volume in the stock approach method. Even at the same CO2 price, the CAHPR differed between the CO2 accounting methods. At low CO2 prices, the CAHPR did not affect situations where the difference of average profit is large by cutting age. On the other
hand, the CAHPR was greatly affected at low CO2 prices when the mean log volume growth changed with tree age. These trends were found to be universal.
Received: September 18, 2001 / Accepted: October 25, 2002
Acknowledgments This study is one of the fifth science study subsidy projects of the Japan Forest Technology Association.
Correspondence to:K. Sakata 相似文献