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131.
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In this study, zebrafish embryos were exposed to titanium dioxide nanoparticles (TiO2 NPs at 0.1, 0.5, 1, 5, 10 mg/L or control) from fertilization to free swimming stage. Hatchability, survival, and malformation rate were not affected by TiO2 NPs at these exposure levels. However, larval swimming parameters, including average and maximum velocity and activity level were significantly affected by TiO2 NPs. Co-exposure to either the glutathione precursor, N-acetylcysteine (NAC), or the glutathione synthesis inhibitor, buthionine sulfoximine (BSO), did not significantly alter the behavioral effects resulting from TiO2 NPs, suggesting that other factor(s) besides oxidative stress may contribute to the behavioral toxicity of TiO2 NPs. Our study also demonstrated that the behavioral endpoints were more sensitive than the others (e.g., hatchability and survival) to detect toxicity of TiO2 NPs on developing fish.  相似文献   
133.
New analysis of wave records at Hualien Harbor during Typhoon Tim in 1994 reveals that for certain wave periods, the ratios of measured wave heights among three available wave stations inside the harbor are unique and roughly remain the same during the severest period of resonance. Since there is no incident infragravity wave (period from 80 to 220 s) information at offshore boundaries, these unique ratios become the surrogate of background truth for checking the performance of numerical simulations. A new simulation effort using a large (45 × 17 km) modeling domain, high-resolution (20 × 20 m) grid and the RIDE wave transformation model were conducted to simulate the observed responses. Comparison of the modeling results with the observations showed reasonable agreement. Additional model studies using ideal bathymetries with the same grid domain and resolution were also conducted to help interpret the prototype modeling results. The effects of two types of commonly used remedies were first examined by using the ideal bathymetry, and then, the prototype bathymetry. The results demonstrated that a single 1-km long, shore-parallel breakwater could significantly reduce the resonance. The results of using three shore-parallel breakwaters, however, are no better. More studies to identify the optimum design associated with the shore-parallel breakwater (location, length, etc.) are necessary for the optimum reduction of resonance at Hualien Harbor.  相似文献   
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A wave-power system which combines the concept of a breakwater and a harbor resonance chamber was developed in this study. In the caisson chamber, a multi-resonant oscillating water column (MOWC) was formed to push or suck air through the air turbine and thus continuously generated the power. The proposed wave-power system has two aims in mind: one is shore protection and the other is to extract energy from the ocean. To achieve an optimal effect of harbor resonance when excited by incident waves of various periods, a 60° opening of the cylindrical chamber with an entrance section and an arc-shaped curve board in front of the caisson was designed. In order to assess the energy-conversion efficiency and the hydraulic performance, a 1/20 model of this system was constructed and tested in the wave tank under various wave conditions. Our experimental data for the amplification factor of the MOWC agree well with previous theoretical results [Lee, J.J., 1971. Journal of Fluid Mechanics 45, 375–394]. The curve board proves to be useful: it not only broadens the resonant period but also increases the energy-extraction rate. The reflection coefficient was found to be generally low and to decrease with increasing wave height. However, due to the relatively high energy loss of the MOWC, only 28.5% of the incident-wave energy was converted into air energy, indicating that there are still areas for further improvement. In any event, the experimental results provided a clear picture of the energy-transformation process, and demonstrated the preliminary feasibility of this wave-energy device.  相似文献   
136.
海带愈伤组织的高效率诱导   总被引:4,自引:0,他引:4  
于1994年1月和11月在青岛太平角和荣成海带育苗场分别采集海带成熟孢子体和幼孢子体,采用培养基诱导方法,以4种培养基诱导海带愈伤组织的效果,成熟海带孢子体的不同部位在MS固体增富2基中形成愈 组织的能力进行了比较;研究了添另不同成分的MS固体增富2基对海带愈伤组织的影响,并比较了4种除菌方法的效果。结果表明,PESI固体2基和MS固体在是诱导海带愈伤组织的理想培养基,其诱导率分别为75.5%和6  相似文献   
137.
中国红毛菜繁殖方式和染色体研究   总被引:8,自引:0,他引:8  
于1989-1992年在福建、江苏和青岛沿海采集红毛菜,进行野外观察,并在室内光照强度为70-100μE/(m2·s)的培养架上培养,每两周更换培养液,完成从原叶体到丝状体整个生活周期培养;对福建和江苏红毛菜有性生殖时两性细胞的构造和作用进行观察,并在生活周期的关键阶段用Wittmann方法压片,计数其染色体。结果表明,生长在福建的红毛菜染色体数目为n=6,2n=12;江苏和青岛的为n=8,说明中国的红毛菜至少有两种;细胞学观察证明,两性细胞已完成受精作用,果孢子是受精后的产物;同时,幼年红毛菜还能放散大量无性孢子,双极萌发成为与亲代相同的植物体,这可使红毛菜在短时期内数量剧增。  相似文献   
138.
于1981年3月在西沙群岛永兴岛采集原绿藻标本。用光镜和电镜对所采原绿藻进行研究。结果表明,原绿藻为简单的原核、单细胞藻类,在同一生境的相同宿主体表有4种不同的细胞构造类型:第1种类型,中央大“液泡”,类囊体单条、平行分散于周围区的细胞质中;第2种类型,中央是大“液泡”,周围区内类囊体多,并形成垛叠;第3种类型,许多小泡充满细胞的大部分,类囊体穿插于小泡之间;第4种类型,有中央大“液泡”,还有许多小泡分散在细胞周围区。上述分类以类囊体和“液泡”的结构和分布为主要分类依据,反映出不同结构的进化意义。表明中国西沙群岛有丰富的原绿藻资源。  相似文献   
139.
用沸水浴的方法提取了带形蜈蚣藻(Grateloupia turuturuYamada)中的多糖成分,并用“苯酚-硫酸法”测定了其含量。用此法得到的多糖标准曲线,相关系数r=0.998 4,结果显示带形蜈蚣藻多糖质量分数为44.91%;利用Bradford法,测得60℃恒温干燥的带形蜈蚣藻可溶性总蛋白质量分数为0.33%;用简单的羟基磷灰石柱层析的方法分离了藻红蛋白,光谱检测证明为R-藻红蛋白,其在带形蜈蚣藻中的质量分数为0.114 5%。本实验测定方法可靠且简便易行。  相似文献   
140.
Sea level variations in the regional seas around Taiwan   总被引:2,自引:0,他引:2  
The patterns and trends of sea level rise in the regional seas around Taiwan have been investigated through the analyses of long-term tide-gauge and satellite altimetry data. Series of tide-gauge data extending over 50 years reveal decadal and interannual variations and spatially-inhomogeneous patterns of generally rising sea level. The East Asia tide-gauge stations around Taiwan show an average trend of +2.4 mm/yr from 1961–2003, which is larger than the reported global rate of +1.8 mm/yr for the same period. These stations also show significantly larger sea level rise rates (+5.7 mm/yr) than global values (+3.1 mm/yr) during the period from 1993–2003. Consistent with the coastal tide-gauge records, satellite altimetry data show similar increasing rates (+5.3 mm/yr) around Taiwan during the same period. Comparisons with temperature anomalies in the upper ocean suggest that thermal expansion and heat advection in the upper layer contribute significantly to the long-term sea level variations in this area with correlations >0.9 for observations after 1992. Thermosteric sea level variations may also explain the interannual and decadal variations of the observed sea level rises around Taiwan. Our analysis also indicates that the altimetry data are only part of a long-term, larger-scale signal. Finally, we have found that a non-linear smoother, LOESS, is more suitable for extracting long-term trends in sea level than the traditional linear regression approach.  相似文献   
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