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81.
Md. Majibur Rahman Khan Yasuo Gotoh Hideaki Morikawa Mikihiko Miura 《Fibers and Polymers》2006,7(4):333-338
Silk fibroin (SF) fiber from theAntheraea pernyi silkworm was treated with a 1.23 N iodine-potassium iodide (I2-KI) aqueous solution, and the structure and physical properties were investigated to clarify the effects of the iodine treatment. The noticeably high weight gain value of SF fiber, about 25 wt% was attributed to the absorption of polyiodide ions in the form of I3 ? and I5 ?. Fourier transform infrared spectroscopy and X-ray diffraction measurements suggested that polyiodide ions mainly entered the amorphous region. In addition, a new sharp reflection on the meridional direction, corresponding to a period of 7.0 Å, was observed and indicated the possibility of the formation of mesophase structure ofβ-conformation chains. Dynamic viscoelastic measurements showed that the damping tanδ peak at 270°C gradually shifted to lower temperature in the iodinated SF fibers, suggesting an enhancement of the molecular motion of the fibroin chains induced by the presence of polyiodide ions. With heating above 254 °C, the iodine component introduced intermolecular cross-linking of SF, and the melt flow of the sample was inhibited. The thermal decomposition stability of fibroin molecules was greatly enhanced by iodine treatment. 相似文献
82.
Effect of extraction method on the concentrations of selected bioactive compounds in mandarin juice 总被引:2,自引:0,他引:2
A mandarin-type citrus fruit, ponkan (Citrus reticulata), was processed by in-line, chopper pulper, and hand-press extractions to investigate the effect of extraction method on the concentrations of bioactive compounds in processed juice. Concentrations of polymethoxylated flavones (tangeretin, nobiletin, and sinensetin) and beta-cryptoxanthin in juice, and inhibitory activities against arachidonate cyclooxygenase and lipoxygenases of the juice extract were analyzed. The juice processed by hand-press extraction contained the largest amounts of nobiletin (3.56 mg/100 mL), tangeretin (4.10 mg/100 mL), and sinensetin (0.13 mg/100 mL). Concentrations of beta-cryptoxanthin were 0.66, 0.59, 0.55, and 0.50 mg/100 mL in chopper pulper, in-line (5/64 in.), in-line (8/64 in.) and hand-press juices, respectively. Both extracts of in-line juices showed greater inhibitory activity toward platelet 12-lipoxygenase than the others. The inhibitory effect of hand-press juice extract on platelet cyclooxygenase activity was remarkable among juice extracts. All juice extracts effectively inhibited polymorphonuclear 5-lipoxygenase activity at nearly the same rate. 相似文献
83.
Many chemical and microbiological methods to estimate the amounts of available nutrients in soil were proposed, but as a rapid laboratory method, microbiological test would appear to have advantages over chemical methods. It could be done more simply and inexpensively in various points. 相似文献
84.
Kousei Yamashita Minobu Kasai Yoko Yamamoto Hideaki Matsumoto 《Journal of plant nutrition》2013,36(6):657-668
The effect of nitrate (NO3) on the activities of hydrogen (H+)‐ATPase and H+‐transport in the plasma membrane vesicles isolated from barley (Hordeum vulgare L. cv. Kikaihadaka) roots was investigated. After treatment with 10 mM NO3 for longer than 24 h, both activities of H+‐ATPase and H+‐transport assayed in the presence of chloride (Cl) were stimulated less than 20%. While H+‐transport activity was approximately two times higher in NO3‐grown roots than in control roots when assayed in the presence of NO3 instead of Cl. This result suggests that NO3 is permeable in the plasma membrane vesicles isolated from NO3‐grown roots rather than that of the control, and thereby stimulate H+‐transport activity through the collapse of positive potentials established by H+‐ATPase. Furthermore, NO3 efflux from roots was markedly enhanced after 48 h of the exposure to NO3. Taken together, NO3 efflux may be mediated by the permeability to NO3 which is induced by NO3. 相似文献
85.
Introduction The relative ability of soils, clay minerals, and hydrous oxides to fix phosphorus has been determined by a variety of methods. In order to study phosphate fixation, it is necessary to rigidly control such factors as concentration of phosphorus added, time of reaction, temperature, and pH. 相似文献
86.
Abstract Morphological and chemical properties of brown forest soils and podzolic soils developed on paleozoic shale under beech and/or cryptomeria have been studied with special reference to the eluviation-illuviation characteristics of Fe and Al. Mobilization of Al was observed even in brown forest soils and its pattern was similar to that in podzolic soils. Its intensity was higher in the brown forest soils developed on the ridge under cryptomeria than in those on the slope under beech. Hence, podzolization is considered to be one of the genetic processes involved in the brown forest soils in question. Furthermore, the value of (Fep+Alp)/clay that is employed to define a podzolic B or spodic horizon indicated the presence of a podzolic B horizon even in the brown forest soils studied, while no spodic horizon was found even in the podzolic soils with a clearly recognizable albic horizon. Moreover, the examination of the degree of podzolization showed that the brown forest soils almost corresponded to Ochreous brown earths. 相似文献
87.
Abstract Recently, fungi with the ability of heterotrophic nitrification have been isolated from acid forest soils (Lang and Jagnow 1986; Stroo et al. 1986). It is suggested that under unsuitable conditions for autotrophic nitrification, heterotrophic processes for NO2 - and NO3 - production could be advantageous. 相似文献
88.
Hideaki Hirai Kazuhiro Yoshikawa Katsutoshi Sakurai Kazutake Kyuma 《Soil Science and Plant Nutrition》2013,59(3):509-519
Abstract Properties of sesquioxides, clay mineralogical composition, and charge characteristics of the soils developed under broad-leaved evergreen forests in Okinawa Prefecture (subtropical climate) and the Kinki District (warm temperate climate) were studied with special reference to their pedogenetic processes in order to reexamine the corresponding parameters of Brown Forest soils and related soils in Japan. The soils in Okinawa Prefecture were characterized by a higher degree of weathering as compared to the soils in the Kinki District. Major differences involved the values of the Fed/Fet ratio for the soil samples throughout the profile, and those of the ratios of (Fed-Feo)/Fet, CEC/clay, and (Feo + Alo)/ clay and the content of CaO plus Na2O for the B horizon. The soils in the Kinki District did not show andic soil properties, nor Al translocation in the profile and, both of which were characteristic of Brown Forest soils developed under cool temperate climatic conditions at high altitudes in the same District. The difference in the degree of weathering were reflected on the charge characteristics at the very surface of the soils, i.e., the surface of the particles of the soils in Okinawa Prefecture exhibited a lower reactivity as compared with those of the soils in the Kinki District. 相似文献
89.
We investigated the dynamics of litterfall and litter decomposition of Sasa dwarf bamboo (Sasa senanensis) and trees to clarify the characteristics of organic matter and nitrogen cycling between plant and soil in a natural cool-temperate mixed forest ecosystem dominated by an understory vegetation of Sasa. Mean annual Sasa litterfall over the 3-year study period was 164 g m?2 year?1, which accounted for approximately 29% of total litterfall. Litter decomposition of Sasa leaf and Sasa culm was significantly slower than that of tree leaf during first and second years. The slow decomposition rates of both Sasa litter types were caused by a significantly higher silicate than in tree leaf. Nitrogen concentration in litter increased as decomposition progressed, especially in Sasa leaf and tree leaf. As a result of the slow decomposition of both Sasa litter types, 111 and 73% of nitrogen to the initial amounts were retained in Sasa leaf and Sasa culm after 3 years, respectively. The amounts of retained nitrogen in Sasa leaf, Sasa culm, and tree leaf after 3 years were 1.29, 0.47, and 3.92 g N m?2, respectively, indicating that the differences of litter decomposition rates among the litter types influence on the nitrogen cycling in forest ecosystem through the differences of the nitrogen release from litter. 相似文献
90.
Yasuko Kifuji Hideaki Hanzawa Yuuichi Terasawa Ashutosh Takeshi Nishio 《Euphytica》2013,190(2):289-295
One hundred sixty-one EST-SNP markers were newly developed for analysis of QTLs for resistance to black rot caused by Xanthomonas campestris pv. campestris by determining EST sequences of a resistant line obtained from cabbage ‘Early Fuji’ and a susceptible broccoli line. A linkage map consisting of nine linkage groups was constructed with a total of 209 markers, including these new SNP markers and previously reported DNA markers. F2 plants grown in a field for 1 month were inoculated by spraying bacteria of race 1, and disease severity of each plant was recorded. Three QTLs, i.e., QTL-1, QTL-2, and QTL-3, were detected on linkage group C2, C4 and C5, respectively. QTL-1, which showed the highest LOD score and additive effect, was again detected in another F2 population used the next year, suggesting QTL-1 to be a major QTL. QTL-2 and QTL-3 could be minor QTLs influenced by environmental factors. The genomic region harboring QTL-1 showed synteny with a region from 5.3 to 7.4 Mb from the short arm end of chromosome 5 of Arabidopsis thaliana, which is rich in TIR-NBS-LRR family genes. The identified SNP markers in QTL-1 are considered to be useful in marker-assisted selection for black rot resistance in Brassica oleracea lines. 相似文献