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241.
Silica (SiO2) exhibits extensive polymorphism at elevated pressures. X-ray diffraction measurements showed that a high-pressure form with a pyrite-type structure, denser than other known silica phases, is stable above 268 giga-pascals and 1800 kelvin. The silicon coordination number increases from 6 in the alpha-PbO2-type phase to 6+2 in the pyrite-type phase, leading to a large increase in density by about 5% at the phase transition. 相似文献
242.
Yasuo KOBAYASHI Aya ITOH Kanae MIYAWAKI Satoshi KOIKE Osamu IWABUCHI Yuji IIMURA Yuri KOBASHI Tomoyuki KAWASHIMA Junichi WAKAMATSU Akihito HATTORI Hiroshi MURAKAMI Fumiki MORIMATSU Takashi NAKAEBISU Takeshi HISHINUMA 《Animal Science Journal》2011,82(4):607-615
The effect of liquid whey feeding on fecal bacteria and their metabolites was assessed in five pregnant sows and 66 growing pigs. Sows were fed a control diet for 4 weeks (control period) followed by the same diet but with whey feeding (5 L/day/pig) for 4 weeks (whey period). One group of growing pigs was given 267 L of whey per pig (whey group), while the other group was not (control group). In both cases, liquid whey was given separately from control diet. Sows in the whey period had feces showing lower pH, lower ammonia concentration, and larger population sizes of total bacteria, lactobacilli and bifidobacteria. The bacterial gene library analysis indicated that Mitsuokella and Megasphaera were more frequently detected, while Clostridium disporicum were detected less frequently in the whey period. Feces from whey‐fed growing pigs showed lower pH than that from control pigs in the early stage of growing. Also, larger populations of total bacteria, lactobacilli and bifidobacteria were recorded in the whey group. From the bacterial gene library analysis, the detection frequency of Lactobacillus reuteri tended to be higher in the whey group. These results indicate that whey feeding influences the hindgut microbiota of pigs, possibly leading to a fermentation shift that is favorable for animal health. 相似文献
243.
Summary A total of 161 variants were obtained in the second seed generation (G2) from scions grafted onto broadbean wilt virus (BWV)-inoculated stocks in Capsicum annuum L. The overall rate of variants in the G1 and G2 generation was as high as 16.5 per cent as compared with 2.0 per cent for the same grafting combination without inoculation. It may be said, therefore, that the hereditary changes were enhanced by virus treatment. The hereditary changes were from dominant homozygous to either heterozygous or recessive homozygous. Among the variants 44.8 per cent were chimeric for one or more genes. As for the mechanism. the possibility of trunsduction was discussed, although these were induced by grafting.The abstract of this paper has been presented at the XIII International Congress of Genetics held in August 1973 at Berkeley, California, USA as both a contributed paper and an exhibit including real herbarial specimen and color pictures of the variants genetically analyzed.Formerly and presently Kihara Institute for Biological Research, Misima, Japan. 相似文献
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Test samples of Japanese larch (Larix leptolepis) heartwood and Japanese beech (Fagus crenata) sapwood were heated for 22 h at constant temperatures (50°–180°C) under three water content conditions. Raman spectra of
the samples were recorded before and after the heat treatments, and spectral changes in the range from 1000 cm−1 to 1800 cm−1 were evaluated using the difference spectrum method. For both wood species, the Raman band intensity at 1655–1660 cm−1 due mainly to the C=C and C=O groups in lignin clearly decreased with increasing heat-treatment temperature (HTT). The spectral
change was thought to reflect the progress of condensation reactions of lignin molecules during the heat treatment. Moreover,
the decrease in band intensity was considerably facilitated by the presence of water in the cell wall, suggesting that the
condensation is closely related to the softening of lignin. From the spectral changes in the wavenumber region of 1200–1500 cm−1, it was considered that wood constituents are partially decomposed at the higher HTT.
Part of this article was presented at the 53rd Annual Meeting of the Japan Wood Research Society, Fukuoka, March 2003 相似文献
248.
Yasuyuki Matsushita Toyoki Inomata Yasuo Takagi Tatsuya Hasegawa Kazuhiko Fukushima 《Journal of Wood Science》2011,57(3):214-218
In this study, polyesters were prepared from sulfuric acid lignin (SAL) that was generated as a by-product during the production
of bioethanol from lignocellulosic materials using ɛ-caprolactone (CL). Carboxylic groups were introduced into SAL by a hydrothermal reaction under alkali conditions. The acid
form (-COOH) of the obtained polymer (HSAL) was dissolved into ɛ-caprolactone and the mixture was heated at 150°C for 12 h with ZnCl2 as a catalyst. The structure of the obtained polymer (PCL-HSAL) was proposed based on results of differential scanning calorimetric
analysis, swelling tests, and dynamic mechanical thermal analysis. The hydroxyl group in HSAL participated in the ring-opening
polymerization of CL. PCL-HSAL with a high HSAL content formed a three-dimensional network that did not dissolve in organic
solvents and did not melt at high temperature. PCL-HSAL showed a high swelling property for a suitable ratio of CL to HSAL. 相似文献
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250.
Ken?Orihashi Ryo?Hiyama Yasuo?KojimaEmail author Minoru?Terazawa Shigehiro?Kamoda Hisatomi?Kasahara Yasuo?Takahashi 《Journal of Forest Research》2003,8(4):317-320
Resistance of the Japanese larch (Larix kaempferi) (Lk), the Kurile larch (L. gmelinii var. japonica) (Lg), and their F1 hybrid (Lg × Lk) to bark stripping by sika deer (Cervus nippon yesoensis) were studied in a forest in Hokkaido by cafeteria tests. Several sets of logs prepared from Lk, Lg, and Lg × Lk were fed to the deer. The stripped areas of logs significantly differed between the Lk/Lg set and the Lk/Lg × Lk set (P 0.05). The resistances of Lg and Lg × Lk to bark stripping was stronger than Lk. This result was similar to those of previous studies on gray-sided voles and mountain hares in Hokkaido. 相似文献