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排序方式: 共有413条查询结果,搜索用时 15 毫秒
1.
Pallab Kumer Sarker Shuichi Satoh Haruhisa Fukada & Toshiro Masumoto 《Aquaculture Research》2009,40(2):225-232
Non-faecal phosphorus (P) was determined for large yellowtail to estimate a minimum available P requirement (Experiment 1) and to justify inorganic P supplementation in a fish meal-based diet (Experiment 2). In Experiment 1, purified diets with incremental P concentrations were fed to yellowtail (mean weight 917 g) at a feeding rate of 1.5% of body weight. The peaks of non-faecal P excretion appeared 5–6 h after feeding in fish fed more than 4.5 g available P kg−1 dry diet. Broken-line analysis indicated that the minimum available P requirement was 4.4 g kg−1 dry diet. In Experiment 2, a purified diet (PR) containing 6.5 g available P kg−1 and a fish meal-based diet with (F1) and without (F0) additional phosphorus were fed to yellowtail (mean weight 1.1 kg) at 1.5% (PR) and 2% (F0 and F1) feeding rates respectively. There was no significant difference in P excretion between fish fed the F0 (5.5 g soluble P kg−1 dry diet) and the PR diet. However, significantly higher (34.5%) amounts of non-faecal P excretions (7.4 g soluble P kg−1 dry diet) were found in fish fed F1 compared with the F0 diet. This suggested that there was an excess of dietary P in the F1 diet and that supplementation is not needed in fish meal-based diets for large yellowtail. 相似文献
2.
A number of papers have been published on nitrification in soil. The problem of the nitrification has become increasingly important because of the appearance of new forms of nitrogenous fertilizers such as ammonium chloride or urea, etc. 相似文献
3.
4.
Ichiro Nagaoka Hideki Sasahara Kei Matsushita Hideo Maeda Shuichi Fukuoka Utako Yamanouchi 《Plant Production Science》2013,16(4):546-553
ABSTRACTWe conducted a quantitative trait locus (QTL) analysis of grain appearance (GA) and agronomic traits of rice, using 128 recombinant inbred lines derived from ‘Emi-no-kizuna’ and ‘Tomohonami’. We detected two promising QTLs associated with GA: qGA4 on chromosome 4 and qGA8 on chromosome 8. qGA4 contributed highly to the greater percentage of perfect grains of the Emi-no-kizuna genotype. In the same region, we detected other QTLs associated with panicle number and spikelet number per panicle. In near-isogenic lines (NILs) in which Emi-no-kizuna alleles were introgressed in the genomic region of only the semi-dwarf 1 (sd1) locus (NIL_1) and both the sd1 locus and qGA8 (NIL_2), respectively, the percentage of perfect grains was significantly higher and the percentages of milky white, basal white, and white back grains were significantly lower than in Tomohonami; and the percentages of milky white and white back grains of NIL_2 were significantly lower than those of NIL_1. These results suggest that introgression in the sd1 region could improve GA, and that the addition of qGA8 could further improve GA. The culm lengths of the NILs were significantly shorter than that of Tomohonami, indicating improved lodging resistance. Grain weight of NIL_2 was significantly smaller than that of NIL_1, suggesting that the effect of qGA8 could be pleiotropic, or the gene that underlies qGA8 could be linked with genes associated with grain weight.Abbreviations: ANOVA: analysis of variance; AT20: mean air temperature in the 20 days after heading; BW: basal white grain; CL: culm length; DAH: days after heading; GA: grain appearance; GW: 1000-grain weight; LOD: logarithm of odds; MW: milky white grain; NIL: near-isogenic line; PG: perfect grain; PL: panicle length; PN: panicle number; PTSN: putative total spikelet number; PVE: percentage of phenotypic variation explained; QTL: quantitative trait locus; RIL: recombinant inbred line; SN: spikelet number per panicle; SNP: single nucleotide polymorphism; WB: white back grain 相似文献
5.
Rhea Joy Carton-Kawagoshi Bessie Joy Elle Valeriano Corre Jr. Shuichi Satoh Masahiro Notoya Daisuke Fujita 《Aquaculture International》2014,22(2):573-584
This study tested the feasibility of a low-cost seaweed biofiltration system for pond-based aquaculture through an indoor-integrated fish-seaweed culture experiment using weekly nutrient supply regime and different seaweed stocking densities. The culture experiment was conducted in glass aquaria that were stocked with Gracilariopsis bailiniae at 3 densities (low = 0.5 kg m?2, middle = 2 kg m?2 and high = 3.5 kg m?2) and provided either with effluents from intensive milkfish (Chanos chanos) culture or with effluent-free seawater (control) as nutrient source. Stocking density was used as a factor in optimizing nutrient availability for growth and nutrient removal under such low water exchange conditions. Our results showed that G. bailiniae cultivated in milkfish effluents had higher growth, biomass and nitrogen yields than those cultivated in effluent-free seawater. Among the different stocking densities tested, highest growth rate (1.03 % day?1) was obtained in the middle density. Increasing biomass and nitrogen yields were also obtained at this density until the end of the culture period. Poorer growth rates at low and high stocking densities were attributed to light limitation from phytoplankton and self-shading, respectively. Due to seaweed treatment, average outflow concentration of NH4 + was reduced from half of its pretreated level. This study showed that a weekly effluent supply at 2 kg m?2 seaweed stocking density can sustainably support the growth of G. bailiniae as long as the dissolved nutrients are present at high levels. 相似文献
6.
Ee Ding Wong Min Zhang Guangping Han Shuichi Kawai Qian Wang 《Journal of Wood Science》2000,46(3):202-209
Two main types of fiberboards were produced using lauan (Shorea spp.) fibers with an isocyanate resin as the binder; fiberboard with a flat, homogeneous (homoprofile), and typical U-shaped (conventional) density profile along the board thickness. The processing parameters included manipulation of mat moisture content distribution, press closing speed, and hot pressing method. The results are summarized as follows: (1) A larger variation was observed in the peak density (PD) and core density (CD) of fiberboards at 0.5g/cm3 mean density (MD) level than in those at 0.7 g/cm3. Generally, PD showed a greater variation than CD, irrespective of MD level. (2) Boards produced using two-step hot pressing recorded substantially higher PD with reduced CD. (3) Multiple regression analysis showed that CD and PD could be calculated based on the other profile defining factors, and a rough estimation for peak distance and gradient factor was possible. (4) Based on static bending, conventional fiberboard had a higher modulus of rupture (MOR) than the homo-profile board but a similar modulus of elasticity (MOE). (5) At 0.5 g/cm3 the MOR and dynamic MOE of fiberboard increased by up to 67% and 62%, respectively, when the PD increased from 0.5 to 1.07 g/cm3. Similarly, an increase of PD from 0.7 to 1.1 g/cm3 resulted in corresponding increases of 55% and 34% in the MOR and dynamic MOE of 0.7 g/cm3 boards. (6) The internal bond strength and screw withdrawal resistance were almost entirely dependent on the CD and MD, respectively. (7) Homo-profile fiberboards registered higher thickness swelling and water absorption than conventional fiberboards throughout the dry/wet conditioning cycle. 相似文献
7.
AbstractThis study examined the performance of mechanically graded timber in bending when exposed to fire at various load
ratios. The test specimens were 150 pieces, each with the dimensions of 60 × 120 × 3500mm. The modulus of elasticity (MOE)
of 150 specimens was measured, and 60 among them were selected to formulate the prediction equation for MOE and modulus of
rupture (MOR), which was used to predict the remaining 90 specimens. These were tested under fire exposure in bending using
three-point loading at 11.1%, 16.7%, 33.3%, 66.7%, and 83.3% of the ultimate load. Using mechanically graded timber, which
means acknowledging the actual strength of the bending member, permits fairly precise application to the targeted design load.
This research confirmed that mechanically graded timber under fire exposure has the following tendencies: under the same load
ratio, time to failure is independent of strength class, and, at any load ratio, the critical strength is dependent on the
timber strength class. The obtained design bending strength under fire exposure using the reduced cross section method and
the reduced strength method conformed to those calculated based on Eurocode 5. Following those findings, mechanically graded
timber can be applied to obtain the design bending strength when taking into account the fire attack. 相似文献
8.
The bark of Japanese cedar (Cryptomeria japonica D. Don) was heated in an N2 atmosphere at 300–900C for 3h to investigate the surface properties of the pyrolyzed residuces and their ability to remove trichloroethylene (TCE) from aqueous solutions. The specific surface areas (S
N) and total pore volumes (V
N) of the pyrolyzed barks steadily increased with rising pyrolysis temperature; no significant differences in the average pore diameters (D
N) were observed at higher temperatures (600–900C). The adsorption capacities of the pyrolyzed residues for TCE were determined under batch mode conditions using an aqueous solution containing 500g TCE dm–3. The adsorption data were well fitted to the Freundlich equation. The adsorption capacity of the bark pyrolyzed at 900C was about five times larger than that of commercial activated carbon.This study was presented at the 10th International Symposium on Wood and Pulping Chemistry, Yokohama, June 1999 相似文献
9.
Shuichi Doi Masakazu Aoyama Shigeru Yamauchi Yasuji Kurimoto 《Journal of Wood Science》2005,51(5):526-530
We investigated the effects of high-temperature drying schedules (120°–130°C) on decay and termite feeding of Japanese larch
timbers. Thermogravimetric analysis was conducted to investigate changes of the wood components. Decay and termite feeding
tests showed that specimens dried under high-temperature schedules were susceptible against a decaying fungus Fomitopsis palustris and attacks from termites Coptotermes formosanus and Reticulitermes speratus. These drying schedules changed chemical components, which were suggested by the thermal analytical result compared to the
control sample. The results of this study indicated that the acceleration of termite feeding takes place even under temperatures
that are comparatively lower than that used in our previous research in which 170°C steaming treatment was applied to Japanese
larch wood. Decay durability against a brown rot fungus also decreased, possibly from production of low molecular weight fragments
when hemicellulose decreased during the high-temperature drying processes. 相似文献
10.
Asahi HORINAKA Yo-Han KIM Atsushi KIMURA Eiji IWAMOTO Tatsunori MASAKI Toshihiro ICHIJO Shigeru SATO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(7):1098
We investigated changes in the predicted functions of the rumen bacterial community in Japanese Black beef cattle during fattening. Nine cattle were fed a high-concentrate diet during the early, middle, and late fattening stages consecutively (10–14, 15–22, and 23–30 months of age, respectively). The rumen fluid and solid samples collected at each stage were subjected to sequencing analyses. The sequencing results were clustered and classified into operational taxonomic units (OTUs). Representative sequences and a raw counting table for each OTU were submitted to the Piphillin website. The predicted functions were revealed by the Kyoto Encyclopedia of Genes and Genomes database as the ratio of the total sequence. In the early stage, “Biosynthesis of secondary metabolites” was significantly higher in the fluid fraction than in the solid fraction. “Two-component system” in the middle stage was significantly lower and “Purine metabolism” in the late stage was significantly higher in the fluid fraction than those in the solid fraction. The fluid fraction was significantly correlated with acetic acid, propionic acid, and bacterial metabolism, such as “Biosynthesis of secondary metabolites” and “Sugar metabolism.” Moreover, the solid fraction was correlated with “Purine metabolism” and “Biosynthesis of secondary metabolism”. These results suggest that the rumen bacterial community in Japanese Black beef cattle adapts to changes in rumen conditions by altering their functions in response to a long-term high-grain diet. 相似文献