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61.
62.
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
63.
Hayahi Saki Ota Emi Kurogi Shuichi Matsushita Yosuke Kanno Yoshiaki Takeshita Minoru 《Journal of General Plant Pathology》2022,88(2):134-137
Journal of General Plant Pathology - Viruses that infect Ranunculus asiaticus L., a globally important greenhouse ornamental, have consistently caused serious damage in Japan. We coupled... 相似文献
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65.
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
66.
Pitchaya Chainark Shuichi Satoh Ikuo Hirono Takashi Aoki Makoto Endo 《Fisheries Science》2008,74(2):380-390
ABSTRACT: Foreign DNA fragments from genetically modified defatted soybean meal (GM SBM) in rainbow trout was traced by nested polymerase chain reaction (PCR) and located by in situ hybridization. Either a GM or non-GM SBM formulated diet (42% protein) was fed to fish (average weight 50.5 g) for 2 weeks. The degradation results showed that the cauliflower mosaic virus 35S promoter (220 bp) fragment was detected in the contents of digestive system only in fish fed the GM SBM diet, and it was not detected on the third day after changing the diet to the non-GM SBM diet. For the possible transferal results, the promoter fragment was detected in the leukocyte, head kidney and muscle only of fish fed the GM SBM diet; it was not detected on the fifth day after changing the diet to the non-GM SBM diet. These results suggest that a foreign DNA fragment was not completely degraded and might be taken up into organs through the gastrointestinal tract. However, foreign DNA was not detected after the withdrawal period. Thus, the data show that uptake of DNA from GM SBM might not remain in the tissues of fish fed GM SBM diet. 相似文献
67.
ABSTRACT: An experiment was conducted to investigate the effect of various organic acid (OA) supplementation on phosphorus (P) and nitrogen (N) retention by rainbow trout fed low fishmeal-based diets. Six experimental diets were formulated, and diet 0.5P was arranged as a positive control diet with 0.5% calcium phosphate and 0P as a negative control without additional P. Diets CA and LA were supplemented with 1% citric (CA), and lactic (LA) acids, respectively, and diets MHA and LTE were supplemented with 1% methionine hydroxy analog (MHA) and 1% liquid trace elements (LTE), respectively. Fish fed CA and LTE showed similar growth to that of the positive control diet. P retention was lowest in the 0.5P group and was elevated with CA and LTE diets. Therefore, in this study it is suggested that it might not be necessary to supplement the low fishmeal-based diet of rainbow trout with P if certain organic acids such as CA are added. 相似文献
68.
Kelly Vargas Yoshiho Asakura Minoru Ikeda Nobuhiko Taniguchi Yasuhiro Obata Katsuyuki Hamasaki Kotaro Tsuchiya Shuichi Kitada 《Fisheries Science》2008,74(3):533-543
ABSTRACT: Allozyme variation of the littleneck clam Ruditapes philippinarum was evaluated in four samples from Nameishi and Matsuo in the Ariake Sea, Ryugatake and Ushibuka in the Shiranui Sea off Kyushu Island, Japan, and in one sample from Jinzhou, China, in the Bohai Sea. A Ruditapes bruguieri sample imported from the Korean Bay off Nampo, North Korea was also studied. Among the R. philippinarum samples, heterozygosity varied from 0.265 to 0.301 and F IS estimates indicated significant homozygosity excess in 15 of 40 loci analyzed. Deviations from Hardy–Weinberg equilibrium were significant in all samples ( P < 0.05). Pairwise F ST estimates indicate that genetic differences between the Chinese and Japanese samples were very low, but significantly different from zero. Mixture proportions with 95% confidence intervals of Chinese R. philippinarum in Nameishi and Matsuo were estimated at 0.4098 [0.2512, 0.5705] and 0.4899 [0.3262, 0.6540], respectively. However, genetic invasion of stocked Chinese R. philippinarum into wild populations in the Ariake Sea remains uncertain due to the low precision of the estimates caused by the high similarity of allele frequencies between Jinzhou and the Ariake Sea. 相似文献
69.
Residual wood meal after extraction of milled wood lignin (WMEM) ofEucalyptus globulus was extracted with alkali and LiCl/N,N-Dimethylacetamide (DMAc). These agents dissolve mainly hemicellulose and cellulose, respectively. The extractability of WMEM in alkali solutions was influenced by the degree of swelling of the cellulose. Under good swelling conditions, considerable amounts of cellulose and lignin were extracted with the hemicellulose. Maximum extractability was about 60% of the WMEM under optimum conditions (3 M or 5 M LiOH or 3M NaOH solution). Some portion of cellulose was extracted with LiCl/DMAc at room temperature. Thus, lignin inE. globulus WMEM was divided into three fractions: hemicellulose-lignin fraction, cellulose-lignin fraction, and insoluble-lignin fraction.Part of this work was presented at the 49th annual meeting of the Japan Wood Research Society, Tokyo, April 1999; and at the 50th annual meeting of the Japan Wood Research Society, Kyoto, April 2000 相似文献
70.
Sakae?HorisawaEmail author Yoh?Sakuma Katsuhiko?Takata Shuichi?Doi 《Journal of Wood Science》2004,50(5):427-432
We investigated a genotype-based assay to discriminate the dry rot fungi Serpula lacrymans. DNAs were extracted from 74 isolates from the northern half of Japan, and internal transcribed spacers (ITS) were amplified by polymerase chain reaction. Genotypes of isolates were checked by restriction fragment length polymorphism (RFLP) using two enzymes, Taq I and Hha I. Among the 74 isolates identified as S. lacrymans in terms of morphologic features, 5 isolates were shown to have been misidentified. Random amplified polymorphic DNA (RAPD) analysis was conducted in order to detect the intraspecific diversity of S. lacrymans isolated in Japan. Because no relation between geographical origin and genetic distances was observed, the intraspecific diversity of S. lacrymans is suggested to be small.Part of this report was presented at the 52nd Annual Meeting of the Japan Wood Research Society, Gifu, April 2002 相似文献