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171.
赤霉素涂抹法对葡萄果实的无核化及果实膨大的影响 总被引:5,自引:0,他引:5
本试验用羊毛脂制成的糊状赤霉素涂抹处理里扎马特、巨峰和先锋葡萄的果梗进行无核化研究 ,试验结果表明 :赤霉素涂抹葡萄果梗后可使葡萄果实无核化并使果实膨大 ,尤其是先锋葡萄可通过一次处理达到较好的无核效果 ,获得的无核果实较对照果实大并且品质优良。涂抹法较水溶液处理法简单、方便 ,有利于在生产上应用。本试验的结果浓度在 10 0~ 30 0 0mg·L-1范围内均有较好的效果 相似文献
172.
Kobayashi J Mori Y Okamoto K Akiyama R Ueno M Kitamori T Kobayashi S 《Science (New York, N.Y.)》2004,304(5675):1305-1308
We have developed an efficient system for triphase reactions using a microchannel reactor. Using this system, we conducted hydrogenation reactions that proceeded smoothly to afford the desired products quantitatively within 2 minutes for a variety of substrates. The system could also be applied to deprotection reactions. We could achieve an effective interaction between hydrogen, substrates, and a palladium catalyst using extremely large interfacial areas and the short path required for molecular diffusion in the very narrow channel space. This concept could be extended to other multiphase reactions that use gas-phase reagents such as oxygen and carbon dioxide. 相似文献
173.
Okamoto TJ Tsuneta S Berger TE Ichimoto K Katsukawa Y Lites BW Nagata S Shibata K Shimizu T Shine RA Suematsu Y Tarbell TD Title AM 《Science (New York, N.Y.)》2007,318(5856):1577-1580
Solar prominences are cool 10(4) kelvin plasma clouds supported in the surrounding 10(6) kelvin coronal plasma by as-yet-undetermined mechanisms. Observations from Hinode show fine-scale threadlike structures oscillating in the plane of the sky with periods of several minutes. We suggest that these represent Alfvén waves propagating on coronal magnetic field lines and that these may play a role in heating the corona. 相似文献
174.
The spatfall prediction techniques used in Hiroshima Bay, Japan, are described. Data are given for the 1977 season. Plankton hauls from seven stations showed successive high peaks of small, medium and large larvae during early August. Small larvae (< 150 μm diameter) peaked at an average of 1,782 larvae per tonne of sea water (m3) on 10 August; medium larvae (151–250 μm) at 1,258/m3 peaked on 12 August as did large settling larvae (251–300 μm) at 350/m3. A small spatfall occurred on 14, 16 and 18 August when an average of 65, 64 and 65 spat per shell, respectively, attached on collectors during 2 days' immersion.A second, much bigger peak of small larvae built up from 16 August to reach an average maximum of 4,702 larvae/m3 on 24 August. Medium larvae peaked at 754 larvae/m3 on 28 August. A red tide then appeared consisting of vast numbers of a dinoflagellate tentatively identified as Gymnodinium simplex, and the anticipated main spatfall did not occur. The effects of red tides are discussed. By 17 September water conditions had improved and an estimated 50–100 spat were reported attached per shell on the collectors. This is about half the 200 spat per shell considered by the industry to be a good set. 相似文献
175.
Toshio?MishimaEmail author Takeshi?Nonaka Akira?Okamoto Mutsuhide?Tsuchimoto Tomoko?Ishiya Katsuyasu?Tachibana Mutsuyosi?Tsuchimoto 《Fisheries Science》2005,71(1):187-194
ABSTRACT: The effect of storage temperature (0, 5, 10, and 15°C) and killing procedure (instant, struggled, temperature shocked, and spinal cord destruction killing) on post-mortem changes in the muscle of the horse mackerel caught near Nagasaki, Japan, was investigated. Temporal changes in adenosine triphosphate (ATP), inosine monophosphate (IMP), and lactic acid concentrations were slowest at 10°C storage temperature. The increase in K -values was slower at 10°C and below than at 15°C storage temperature. In addition, 10°C storage temperature was most suitable for maintaining a constant breaking strength value of the muscle. Regarding the effect of killing procedure, temporal changes in ATP, IMP, and lactic acid concentrations were slowest when killed by spinal cord destruction. The increase in K -value and the decrease in breaking strength were also slowest in the spinal cord destruction group. From these results, it was considered that storage at 10°C temperature and spinal cord destruction killing procedure were most effective in delaying post-mortem change in the horse mackerel. 相似文献
176.
Maria R. M. Coimbra Kazunobu Kobayashi Shinrokuro Koretsugu Osamu Hasegawa Eriko Ohara Akiyuki Ozaki Takashi Sakamoto Kyoshi Naruse Nobuaki Okamoto 《Aquaculture (Amsterdam, Netherlands)》2003,220(1-4):203-218
We report the first genetic linkage map of the Japanese flounder (Paralichthys olivaceus) constructed with 111 microsatellite markers and 352 AFLP fragments. The parental male linkage map consisted of 25 linkage groups while the female map consisted of 27 groups, with an average resolution of 8 and 6.6 cM, respectively. We have identified linkage among 96% of the markers and the total map length was estimated to be around 1000–1200 cM. This study reports the first low-density linkage map for the Japanese flounder and describes differences in sex recombination. Recombination rates were higher in male flounder compared to the female (7.4:1), a rare condition among vertebrates. This map is a starting point for the mapping of single loci and quantitative traits in flatfish species. 相似文献
177.
通过肥料埋藏试验及盆栽试验方法,研究了LP30日型和LP70日型包膜尿素氮素溶出对油菜生长及产量的影响。研究表明:一级反应动力学模型可很好地描述LP30日型和LP70日型包膜尿素氮素的溶出过程,其溶出速率常数分别为0.0132和0.0067。硫酸铵处理的油菜株高、株重及产量均随氮素用量的增加呈指数型增加趋势,而LP30日型和LP70日型包膜尿素处理的油菜株高、株重及产量则均随氮素用量的增加呈直线型增加趋势。与硫酸铵处理相比,LP30日型和LP70日型包膜尿素处理,在施氮量为N 0.1 g kg-1和N 0.2 g kg-1条件下,均可使油菜株高、株重及产量显著下降(P<0.01),且以LP70日型包膜尿素下降最为明显;在施氮量为N 0.4 g kg-1条件下,LP30日型包膜尿素可使油菜株高、株重及产量显著提高(P<0.01),而LP70日型包膜尿素则使油菜株高、株重及产量提高不明显,但这两种包膜尿素均可明显提高肥料溶出氮素的利用率。 相似文献
178.
S. Okumura K. Okamoto R. Oomori H. Sato A. Nakazono 《Fish physiology and biochemistry》2003,28(1-4):515-516
Two types of spawning experiments were carried out using a small or a large tank in order to determine the reason for the low fertilization rate in artificially reared red spotted grouper. The mean fertilization rate in the large tank (45%) was significantly higher than the one in the small tank (22%). The fertilization rates were high when a pair spawned underwater (84%) compared with the `jump-type' spawning behavior (31%). Spawning in the large deep tank was effective for improving the fertilization rate in this species. 相似文献
179.
180.
Arimoto-Kobayashi S Takata J Nakandakari N Fujioka R Okamoto K Konuma T 《Journal of agricultural and food chemistry》2005,53(3):812-815
An evaluation of the in vivo antigenotoxic potential of beer components on heterocyclic amines including 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) and 3-amino-1-methyl-5H-pyrido[4.3-b]indole (Trp-P-2) was determined with particular focus on the target organs of tumorigenesis, and the protective mechanisms involved were investigated. Beer-solution, consisting of a freeze-dried and dissolved sample, given as drinking water, reduced the formation of MeIQx-DNA adducts in mouse liver and lungs. Beer-solution added in the diet as a mimic of food additives also significantly reduced the amount of DNA adducts present in the liver, lung, and kidney DNA of mice fed with MeIQx compared to control mice fed with MeIQx in the absence of beer-solution. The amount of adducts present in the liver of mice with single or continuous administration of Trp-P-2 was significantly reduced when beer-solution was given as part of the diet compared to control mice given Trp-P-2 without beer-solution. Protective effects were observed both with lager- and stout-type samples. In an effort to investigate the mechanisms responsible for the observed protective effects, the effects of beer-solution on metabolizing enzymes for heterocyclic amines were examined. Beer-solutions inhibited the metabolic activation of Trp-P-2 to Trp-P-2(NHOH), as demonstrated by HPLC analysis. Considering the overall suppression of the genotoxicity of MeIQx and Trp-P-2 by beer, we have shown that beer components can inhibit the metabolic activation of heterocyclic amines and subsequently suppress the observed genotoxicity. The results of this study show that beer components are protective against the genotoxic effects of heterocyclic amines on target organs associated with tumorigenesis in vivo. 相似文献