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21.
AbstractThe accident at Fukushima Dai-Ichi Nuclear Power Station (NPS) extensively contaminated the agricultural land in the Tohoku region of Japan with radioactive cesium [sum of cesium-134 (134Cs) and cesium-137 (137Cs)]. We evaluated the status of radioactive cesium (Cs) contamination in soil and plants at the Field Science Center of Tohoku University, northern Miyagi prefecture, 150 km north of the NPS. In seven pastures with different management, we examined: (1) the distribution of radioactive Cs in soil, (2) the concentration of radioactive Cs in various herbaceous plant species and (3) the change in radioactive Cs content of plants as they matured. We collected samples of litter, root mat layer (root mat soil and plant roots), and subsurface soil (0–5 cm beneath the root mat) at two to three locations in each pasture in December 2011 and May 2012. The aboveground parts of herbaceous plants (four grasses, two legumes, and one forb species) were collected from May 9 to June 20, 2012, at 14-d intervals, from one to five fixed sampling locations in each pasture. The distribution of radioactive Cs in soil differed among pastures to some degree: a large proportion of radioactive Cs was distributed in the root mat layer. Pasture management greatly influenced the radioactive Cs content of herbaceous plants (p < 0.001); plant species had less influence. Radioactive Cs content was highest (> 3 kBq kg?1 dry weight) on May 9 and significantly decreased with maturity (p < 0.001) for most of the pastures, whereas it remained low (0.04–0.18 kBq kg?1 dry weight) throughout the measurement period in the pasture where composted cattle manure was applied. The soil-to-plant transfer factor was negatively correlated to pH(H2O) (R2 = 0.783, p < 0.001) and exchangeable K content (R2 = 0.971, p < 0.001) of root mat soils, which suggests that surface application of composted cattle manure reduces plant uptake of radioactive Cs by increasing the exchangeable K content of the soil. The radioactive Cs content of plants decreased with plant maturity; its degree of decrease (May 9 to June 6) was smaller in legumes (80.6%) than grasses (55.5%) and the forb (58.6%). Radioactive Cs content decreased with plant maturity; also, the proportion remaining in the aboveground plant was higher in legumes (80.6%) than grasses (55.5%) and the forb (58.6%). 相似文献
22.
Quantification of fruit fall is the only way to compare fruit food availability among different studies.This study aims to reveal the general characteristics of fruit fall in temperate forests, which should offer indispensable information for using fruit fall data as food availability for frugivores.Fruit fall in three warm-temperate and two cool-temperate forests on Yakushima, an island in southwestern Japan, were studied for two years in one cool-temperate plot of 50 m × 50 m in size and for four years in other plots of 100 m×50 m in size.The elevations of the plots ranged 170-1200 m a.s.l.Fruit fall was highest in the lowland forests (599 and 564 DW kg·ha-1·year-1 and lowest in the mid-elevation forest (198 DW kg·ha-1·year-1).Fleshy fruits and food-fruits for Japanese macaques constituted 3-37% and 4-87% of the total fruit fall, respectively.When only fleshy-fruit fall was compared, it was higher in the western lowland forest (222 DW kg·ha-1·year-1) than in any other forests (9-66 DW kg·ha-1·year-1).The pulp of fleshy fruits, presumably the edible parts for frugivores, was only 1.1-12.7% of the total fruit fall.The edible parts for Japanese macaques constituted 3-54% of the fruit fall, showing a high value where acorns are abundant.Half of the fruit-fall biomass consisted of only one or two non-fleshy-fruited species, which are usually dominant in many other temperate forests, such as Quercus and conifers.These variations agreed with the variations in occurrence of frugivorous (such as Japanese macaques). 相似文献
23.
Yamada S Yoshida A Yoshida K Kuraishi T Hattori S Kai C Nagai Y Sakoda T Tatara M Abe S Fukumoto S 《The Japanese journal of veterinary research》2012,60(1):15-21
Nematodes of the family Heligmonellidae (Heligmosomoidea; Trichostrongylina) reside in the digestive tracts of rodents and lagomorphs. Although this family contains large numbers of genera and species, genetic information on the Heligmonellidae is very limited. We collected and isolated adult worms of three species in Japan that belong to the family Heligmonellidae, namely Heligmonoides speciosus (Konno, 1963) Durette-Desset, 1970 (Hs) from Apodemus argenteus, Orientostrongylus ezoensis Tada, 1975 (Oe) from Rattus norvegicus and Lagostrongylus leporis (Schulz, 1931) (Ll) from Pentalagus furnessi, and sequenced the entire internal transcribed spacer regions, ITS-1 and ITS-2 of ribosomal DNA. ITS-1 of Hs, Oe and Ll was 426, 468 and 449 bp in length, and had a G+C content of about 41, 41 and 37 %, respectively. ITS-2 of Hs, Oe and Ll was 297, 319 and 276 bp in length and had a G+C content of about 38, 40 and 28%, respectively. The data of Hs, Oe and Ll were compared with those of two other known species within the family Heligmonellidae, Calorinensis minutus (Dujardin, 1845) (Cm) and Nippostrogylus brasiliensis (Travassos, 1914) (Nb), and with those of two species of Heligmosomidae (Heligmosomoidea), Heligmosomoides polygyrus bakeri and Ohbayashinema erbaevae. Phylogenetic analysis placed Hs, Oe and Ll in the same clade with Cm and Nb, forming a Heligmonellidae branch in both ITS-1 and ITS-2, separate from the Heligmosomoidea branch. These results demonstrated that the ITS-1 and ITS-2 sequences are useful for differentiating the Heligmonellidae nematode species. This study is the first to describe the ITS-1 and ITS-2 sequences of Hs, Oe and Ll. 相似文献
24.
Preparation of phenol formaldehyde resin from phenolated wood 总被引:2,自引:0,他引:2
The technique for preparing phenol formaldehyde resin from phenolated wood (PWF) and its characters were studied and analyzed.
Poplar (Populus spp) wood meal was liquefied by phenol in the presence of sulfuric acid as a catalyst. After the liquefied products were cooled,
alkaline catalyst and formaldehyde were added. The mixture was kept at (60±2)°C for 1h and then was heated to (85±2)°C for
1h. The influence of molar ratio of formaldehyde to phenol (F/P) was investigated. The results showed when the molar ratio
of formaldehyde to phenol was over 1.8, the PWF adhesives had high bond quality, bond durability and extremely low aldehydes
emissions.
Foundation item: The research was supported by Sino-Japanese Technical Cooperation Project (2-1-b) and the key technologies R & D Program
for the 10th Five-Year Plan (325-11).
Biography: LI Gai-yun (1974-), female, Assistant professor in Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing
100091, P. R. China
Responsible editor: Zhu Hong 相似文献
25.
To clarify the differences in susceptibility of six species in the Fagaceae (Quercus crispula, Quercus serrata, Quercus acutissima, Quercus phillyraeoides, Quercus glauca, and Castanopsis cuspidata var. sieboldii) to Raffaelea quercivora, we inoculated this fungus on seven potted 5-year-old seedlings of each species, observed symptom development, and measured xylem pressure potential (XPP) after inoculation. The first death was observed on the 11th day in Q. crispula and on the 56th day in Q. serrata. The number of dead seedlings of Q. crispula and Q. serrata were five and one, respectively, whereas no mortality was observed in the other four species. The XPP of inoculated seedlings in both Q. crispula and Q. serrata decreased after inoculation. In contrast, the XPP of inoculated seedlings of the other four species remained almost the same as in the control seedlings. These results indicate that R. quercivora is pathogenic to Q. crispula and Q. serrata and that the susceptibility of the six Fagaceae species in our study differed among species. 相似文献
26.
Thu-Thuy NGUYEN Mono Sophie MOTSIRI Moeti Oriel TAIOE Moses Sibusiso MTSHALI Yasuyuki GOTO Shin-Ichiro KAWAZU Oriel Matlhahane Molifi THEKISOE Noboru INOUE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(2):217-220
A total of 231 serum samples were collected from sheep (n=9), goats (n=99) and cattle (n=123) in northeastern KwaZulu-Natal, South Africa. Trypanosome infection was detected using Trypanosoma brucei brucei crude antigen (TbbCA) and T. congolense crude antigen (TcoCA) ELISA assays. Recombinant antigen (T. evansi GM6 which consisted of 4 repeat domains, TeGM6-4r) ELISA and immunochromatographic test (ICT) were also used. Crude antigen ELISA, TeGM6-4r-ELISA and ICT detected 27.3%, 29% and 19.9% of trypanosome seropositive samples, respectively. Trypanosome infection prevalence in cattle and goats was 35.8–46.3% and 0–9.1%, respectively. Out of 9 sheep serum samples, 2–4 sera (22.2–44.4%) were positive. The detection performance of crude and recombinant antigen ELISAs was relatively similar (K=0.6–0.7); both are recommended for reference diagnosis and large scale epidemiological surveys. There is potential application for ICT in
on-site diagnosis, but its sensitivity should be improved. 相似文献
27.
Kayoko Imai Tohru Mitsunaga Hiroyuki Takemoto Toshihiro Yamada Shin-ichiro Ito Hideo Ohashi 《Journal of Wood Science》2009,55(2):126-132
The extracts of Quercus crispula infected by the ambrosia fungus, Raffaelea quercivora, were investigated. Phenol and tannin analyses indicated that normal sapwood (NS) contained a considerable amount of hydrolysable
tannins, while infected colored sapwood (IS) contained less hydrolysable tannins and more phenols than NS. In treating pentagalloyl
glucose (PGG), which is a model compound of hydrolysable tannins, with a culture medium of R. quercivora, PGG was rapidly hydrolyzed to produce gallic acid. The resulting gallic acid decreased in concentration over the subsequent
cultivation period eventually disappeared. Measuring tannase and laccase activities of the culture medium of R. quercivora, tannase activity increased gradually from the beginning, while laccase activity increased rapidly at 5 days of incubation
and disappeared at 8 days. An oxidative product from gallic acid treated with laccase was isolated by preparative high performance
liquid chromatography, and was identified as purprogallincarboxylic acid (PGCA) by nuclear magnetic resonance spectroscopy
and electron-impact mass spectrometry. PGCA was present in a 70% aqueous acetone extract of IS, and showed slight growth inhibition
against R. quercivora.
Part of this study was presented at the 57th Annual Meeting of the Japan Wood Research Society, Hiroshima, Japan, 2007 相似文献
28.
Seven reactions take place consecutively and competitively during the hydroxymethylation of phenol in aqueous alkaline media. This hydroxymethylation is the first step in the formation of phenolic resins and has long been studied. However, the rate equation, which can describe the seven reactions in those reaction systems where the alkali/phenol molar ratios are <1.0, has not yet been obtained. The authors present a rate equation (in a differential form) for a computer simulation. This equation involves the concentration of hydroxide ion, [OH–], which changes with the change in the composition of the reaction system and cannot be expressed as a function of reaction time. However, the value of [OH–] can be obtained by numerical calculation. In the computer simulation the reactions occur for an infinitesimal unit of time, and the changes in the concentrations of formaldehyde, phenols, and hydroxide ion are calculated. The next step of the reaction takes place according to the reaction conditions that result from the previous step. In this manner the reactions progress step by step in a computer. Using this method we can describe the reaction time course, (i.e., the changes in the concentrations of phenol, formaldehyde, and five species of hydroxymethylphenols with the reaction time).Part of this paper was presented at the 47th Annual Meeting of the Japan Wood Research Society, Kochi, April 1997 相似文献
29.
30.
Shin-ichiro Iwatani Hiroshi YakushijiNobuhito Mitani Naoki Sakurai 《Postharvest Biology and Technology》2011,62(3):305-309
Destructive acoustic vibrations produced by probe penetration were measured by a texture measurement device to clarify the characteristic flesh texture of nine grape cultivars and to examine methods for quantitative evaluation of grape flesh texture. The texture index (TI) is based on the energy density between 10 Hz and 3.2 kHz and was calculated using signals obtained with a piezoelectric sensor attached to a wedge-tipped probe. Using this index, we successfully classified nine grape cultivars according to flesh texture as crisp, non-crisp, or intermediate. The breaking force measured by a conventional puncture test did not identify these three types of texture. The breaking force was correlated with the TI calculated using 0-50 Hz vibrations but not with that calculated using the 10-3.2 Hz vibrations. This suggests that the former represents flesh firmness, and TI values measured at frequencies greater than 10 Hz evaluate characteristic textures of grape flesh that could not be evaluated using a load sensor installed in a conventional stress-strain analyzer. 相似文献