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71.
Gypsum particleboard (GPB) has high thickness swelling (TS), high water absorption (WA), and low mechanical properties compared with cement-bonded particleboard. The properties of GPB were improved by adding cement. The experimental results showed that GPB with the added cement had good physical and mechanical properties compared with those of gypsum particleboard with no added cement. The TS and WA of gypsum particleboard with added cement were reduced by 10%. The mechanical properties of GPB, such as internal bond strength (IB), modulus of rupture (MOR), and modulus of elasticity (MOE), increased when the GPB was made with added cement. The properties of GPB improved relative to the quantity of cement added. With an increase of cement content from 5% to 10%, the TS and WA were reduced, and the IB, MOR, and MOE were increased. In contrast, the TS and WA increased and the IB, MOE, and MOR decreased when the cement content was increased from 15% to 30%. Thus the physical and mechanical properties of GPB were successfully improved when the added cement content was 10%.An outline of this paper was presented at the 47th Annual Meeting of the Japan Wood Research Society in Kochi, April 1997 相似文献
72.
The influence of proanthocyanidin (PA) structures contained in bark on color development in the vanillin-hydrochloric acid (V-HCl) method used widely as a quantitative method for measuring PA were examined. The maximal absorption wavelength was different in terms of the bark from which the PA was obtained. Phenyl nucleus (resorcinol, phloroglucinol) constituting the A-ring of PA reacts with vanillin to produce the color. The maximal absorption wavelengths of the solutions from synthesized procyanidin and profisetinidin were 500 and 540 nm, respectively, indicating that the color tone differs in the V-HCl method based on the hydroxylation patterns of the A-ring. The colored solution of (+)-catechin with vanillin was dialyzed, and the resulting product (C-VC) was analyzed by gel permeation chromatography and 1H nuclear magnetic resonance. It was found that C-VC was a polymer complex consisting of 9mol (+)-catechin moieties and 10mol vanillin moieties. It was presumed that the cationized vanillin molecules that do not combine with (+)-catechin play an important role on color development in the presence of C-VC.This study was presented at the 44th and 45th Annual Meetings of The Japan Wood Research Society, Nara and Tokyo, April 1994 and April 1995 相似文献
73.
Malik Ashiq Rabbani Aki Iwabuchi Yoshie Murakami Tohru Suzuki Kenji Takayanagi 《Euphytica》1998,101(3):357-366
An investigation was conducted to determine the extent of diversity and relationships among the Brassica juncea germplasm
from Pakistan using morphological characters. A total of 52 accessions, including the collected germplasm as well as commercial
cultivars/improved lines, were studied under field conditions at Tsukuba, Japan during 1995 and 1996. All the accessions were
characterized for 35 agro-morphological characters from seedling emergence to crop maturity. Morphological data were analyzed
by numerical taxonomic techniques using two complementary procedures: cluster and principal component analyses. Phenograms
based on Euclidean distance placed the accessions into six groups during both years. Landrace groups were primarily associated
with morphological differences among the accessions and secondarily with the breeding objectives and horticultural uses. The
mustard germplasm collected from Pakistan showed a comparatively low level of phenotypic variation amongst themselves and
were genetically similar to the oilseed cultivars. However, the oilseed forms and vegetable cultivars were genetically distinct.
This study revealed that the evaluated germplasm appears to have a narrow genetic base which undergoes a high level of genetic
erosion. This is perhaps due to the use of the same ancestors in the selection of new lines for similar horticultural traits,
replacement by major crops and changes in agricultural land uses.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
74.
Genetic diversity in mustard (Brassica juncea L.) germplasm from Pakistan as determined by RAPDs 总被引:6,自引:0,他引:6
Malik Ashiq Rabbani Aki Iwabuchi Yoshie Murakami Tohru Suzuki Kenji Takayanagi 《Euphytica》1998,103(2):235-242
The genetic diversity and the relationships among a collection of mustard (B. juncea) germplasm, including 41 accessions collected
from Pakistan, 6 oilseed cultivars/ lines and 5 Japanese vegetable cultivars, were evaluated using random amplified polymorphic
DNA (RAPD) markers. A total of 198 polymorphic amplified products were obtained from 30 decamer primers. Of these, 14 were
unique to the accession PAK-85835 and 37 were specific to PAK-85839. Based on pair-wise comparisons of RAPD amplification
products, genetic similarity was estimated using similarity coefficients of Nei & Li (1979) and a dendrogram was constructed
using the unweighted pair-group method with arithmetic averages (UPGMA). Cluster analysis based on these genetic similarities
placed most of the collected germplasm and oilseed cultivars/lines close to each other, showing a low level of polymorphism
between the oilseed accessions collected in Pakistan. However, the clusters formed by the oilseed collections and cultivars
were distinct from those formed by the vegetable cultivars. A low level of genetic variability of oilseed mustard in Pakistan
was attributed to the selection for similar traits and horticultural uses. The farmers' preference for more remunerative crops
and perhaps the close parentage of these accessions further contributed towards their little diversity. The study demonstrated
that the RAPD is a simple and fast technique to compare the genetic relationships and the patterns of variation among accessions
of this crop.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
75.
Sakae Horisawa Masahide Sunagawa Yutaka Tamai Yuki Matsuoka Tohru Miura Minoru Terazawa 《Journal of Wood Science》1999,45(6):492-497
The physical properties of sawdust including porosity, water retention, and water drainage were analyzed to prove its suitability for use as an artificial soil in the automatic decomposer-extinguisher (GADE) machine. The physical and chemical properties of residual sawdust from the GADE machine were also analyzed, the mechanical abrasion of sawdust in the GADE machine was tested, and the morphology of this residue was observed through a scanning electron microscope to investigate changes of these properties in the medium of decomposing garbage. Sawdust, which showed a lower specific gravity and larger porosity than soil, is considered capable of supplying air to bacteria. It was found that sawdust became worn from the operation of the machine. The spaces of residual sawdust were still observed, but water drainage decreased. The portion of hollocellulose in residual sawdust decreased, although the extractives in it increased. Results indicated that the capacity of sawdust to function as an artificial soil in the GADE machine was decreased owing not only to the destruction of sawdust grain but also to the adherence of products from decomposition, such that sawdust needed to be replaced every few months.Part of this report was presented at the 43rd annual meeting of the Japan Wood Research Society, Morioka, April 1993 相似文献
76.
Nobuya Hishiyama Hideki Kayanuma Tohru Matsui Hideo Yano Tsunenori Suganuma Masayuki Funaba Hiroshi Fujise 《Canadian journal of veterinary research》2006,70(4):305-307
Most mammals, including dogs, synthesize vitamin C in the liver. We measured the plasma concentration of vitamin C to assess the body vitamin C status in 15 dogs with a portosystemic shunt (PSS). The plasma biochemical parameters indicated liver abnormalities in all the dogs. In contrast, the plasma concentration of vitamin C ranged from 2.21 to 9.03 mg/L in the 15 dogs and was below the reference range (3.2 to 8.9 mg/L) in only 2 dogs. These findings suggest that vitamin C status is not impaired in dogs with PSS. 相似文献
77.
Takahashi H Ishihara T Hase S Chiba A Nakaho K Arie T Teraoka T Iwata M Tugane T Shibata D Takenaka S 《Phytopathology》2006,96(8):908-916
ABSTRACT The biocontrol agent Pythium oligandrum produces glycoprotein elicitor in the cell wall fraction, designated CWP, and induces resistance to a broad range of pathogens. To understand the mechanism of CWP-induced resistance to pathogens, gene expression at the early stage of CWP treatment in tomato roots was analyzed using a cDNA array. At 4 h after CWP treatment, 144 genes were up-regulated and 99 genes were down-regulated. In the 144 up-regulated genes, nine genes exhibited about eightfold increased expression. Analysis of the response of these nine genes to three commercial plant activators indicated that a high level of one gene, beta-cyanoalanine synthase gene (LeCAS) encoding hydrogen cyanide (HCN) detoxification enzyme, was stably induced in tomato roots by such treatment. However, expression of LeCAS was not significantly induced in tomato roots at 4 h by abiotic stresses, whereas only a very low level of induction of such expression by cold stress was observed. This LeCAS expression was also induced after exogenous treatment with a low level of 1-amino-cyclopropane-1-carboxylate as the precursor of ethylene, but not with either salicylic acid or methyl jas-monate. The induction of LeCAS expression in CWP-treated and plant activator-treated roots is likely to be caused by the detoxification of HCN during ethylene production. Transient activation of LeCAS expression caused by ethylene production in tomato roots may be a general phenomenon in fungal elicitor-induced and synthetic plant activator-induced resistance. LeCAS seems to be useful for screening possible novel plant activators for plant protection against pathogens. 相似文献
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