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81.
In this paper the finite element analysis was carried out for a composite vertical axis wind turbine with lift-drag combined starting structures to ensure the structure safety of a vertical axis wind turbine(VAWT). The static and modal analysis of rotor of a composite vertical axis wind turbine was conducted by using ANSYS software. The relevant contour sketch of stress and deformation was obtained. The analysis was made for static structural mechanics, modal analysis of rotor and the total deformation and vibration profile to evaluate the influence on the working capability of the rotor. The analysis results showed that the various structure parameters lie in the safety range of structural mechanics as given in the relative standards. The analysis showed the design safe to operate the rotor of a vertical axis wind turbine. The methods used in this study can be used as a good reference for the structural mechanics′ analysis of VAWTs. 相似文献
82.
Free-living Porphyra haitanensis conchocelis was cultured under continual light,then it was treated with Van,DIDS and SITS,the inhibitors of inorganic carbon utilization,to study the mechanism of inorganic carbon utilization in the conchocelis.The results indicate that Van inhibits the utilization of inorganic carbon most,with a rate of 71.3%,and the rates of DIDS and SITS are relatively lower,42% and 35.5% respectively.The inhibition rate of Az is 25.3%,which indicates the external CA is not an important part of its inorganic carbon uptake.A complementary conclusion is that the main part of inorganic carbon absorption in P.haitanensis conchocelis is through active transport of HCO3^- and CO2. 相似文献
83.
Mao Mori Kohei Mizobata Taro Ichii Philippe Ziegler Takehiro Okuda 《Fisheries Oceanography》2022,31(1):19-39
The Antarctic toothfish (Dissostichus mawsoni) is an important fishery species widely distributed in the Southern Ocean, especially in areas covered by sea ice. Understanding fish distributions and life cycles, including the transport and survival of eggs and larvae, is essential for the assessment and sustainable management of the fishery. However, owing to difficulties with in situ winter observations, information on the early life stages of D. mawsoni is lacking. Here, we investigated the transport pathways of fish eggs and larvae through a particle tracking study, using satellite-derived ocean surface velocities in the East Antarctic region, which includes important D. mawsoni habitats and exploratory fisheries. Our results indicate that particles released from continental slopes are more likely to be successfully transported to suitable settlement grounds than those released from the BANZARE Bank (the southern region of the Kerguelen Plateau), which is situated further north and has been hypothesized to be a potential spawning ground for D. mawsoni. This study demonstrates successful source–settlement connections in relation to ocean recirculation and suggests important settlement regions for D. mawsoni larvae in the East Antarctic region. 相似文献
84.
Reduction of transport stress of ayu by obligated schooling 总被引:3,自引:0,他引:3
KEI'ICHIRO IGUCHI FUMINARI ITO KOGI OGAWA NAOTO MATSUBARA TAIGA YODO TSUGIKO YAMASAKI 《Fisheries Science》2002,68(4):849-853
We investigated stress responses of ayu Plecoglossus altivelis under the hypothesis that overcrowding during transport can be a stressor and the stress predisposes fish to disease by decline in immunocompetence. The extent of stress response was determined under different fish densities. As inferred from the serum concentration of cortisol 1 day after the treatment, the density at more than 23 kg/m3 , which was within the range of normal transporting procedures, acutely evoked intense stress responses. To examine a possible way to reduce the stress response of fish under crowding conditions, we compared two fish groups established in water tanks with circulating (whirling) and turbulent currents at the same density. The cortisol levels 1 day after the treatment were 2.5-fold higher in turbulent current than in whirling current. Fish in whirling current formed a school, while those in turbulent current aggregated with each other. Schooling of fish induced by water flow may reduce their stress responses during transport. A transport system with a directional water flow should keep fish in good condition without reducing the number of fish contained. 相似文献
85.
Modelling the transport of particles in the North Sea with reference to sandeel larvae 总被引:2,自引:0,他引:2
The transport of particles representing sandeel larvae in the North Sea is simulated with a three-dimensional circulation model for the years 1976 to 1990. A great year-to-year variability in drift patterns is demonstrated. The results may explain some of the observed differences in recruitment between the main sandeel areas in the North Sea. In the northern sandeel area it seems that strong year classes are unlikely if the retention due to unfavourable currents is poor, and that a high retention in the summer may favour a good year class. In the southern sandeel area no clear coupling between year class strength and larval drift is found, possibly because the retention always seems large enough for a potentially good year class. For more quantitative use of such models in relation to sandeel recruitment, more biological knowledge is obviously needed on larval vertical distribution and timing of sandeel hatching and settling. 相似文献
86.
Azusa SOMEYA Ryoko FUKUSHIMA Michiko YOSHIDA Yasuyuki TANAHASHI Tangmunkhong PRAPEUK Reiko IIZUKA Hiroshi HIRAMI Atsushi MATSUDA Shunichi TAKAHASHI Goro KURITA Takashi KIMURA Misuzu SEO Masayuki FUNABA Yoshii NISHINO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2014,76(8):1157-1160
87.
A. Cullinane 《Equine Veterinary Education》2014,26(9):456-457
88.
武夷山土壤氮素垂直分异规律研究 总被引:1,自引:0,他引:1
为探讨武夷山自然保护区土壤氮素的垂直分异规律,在武夷山自然保护区不同海拔的林分内设立标准地,对不同海拔和土层土壤全氮、水解性氮、铵态氮、硝态氮等指标进行测定,分析土壤不同氮素的垂直分异规律。结果表明,武夷山自然保护区0-20 cm土层土壤全氮、水解性氮、铵态氮、硝态氮含量总体上随海拔高度的升高呈增加趋势,而20-40 cm及40-60 cm土层不同形态氮素含量随着海拔高度的变化呈现一定的波动;在土壤剖面垂直分布上,土壤全氮、水解性氮、铵态氮、硝态氮含量随着土层深度的增加呈下降趋势,土层深度对土壤不同氮素含量的影响达显著水平,但土壤全氮含量在不同土层间的差异规律不明显。 相似文献
89.
根据湖南秋季的气候特点,2012~2014年在湖南省岳阳市农业科技示范园、长沙市农作物品种展示基地(浏阳市淳口镇黄荆坪村)进行大棚秋季无籽西瓜品种立架栽培试验研究,参试品种为泉蜜308无籽、金丽黄无籽、博达隆一号无籽、黑童宝无籽、博帅无籽、神玉无籽、博达隆三号无籽、绿虎无籽、金蜜红无籽、蜜童无籽。试验结果表明,所有参试品种均表现出耐高温性强、抗性强、果皮外观漂亮、商品率高、瓤色鲜艳、口感好、无籽性能好、品质上佳、产量高等优点,适宜湖南丘陵地区与洞庭湖区等地秋季大棚立架栽培种植。 相似文献
90.