Design formulations for supplemental viscous dampers to highway bridges

Design formulas for supplemental viscous dampers to building structures are readily available in FEMA provisions and MCEER research reports. However, for the design of supplemental viscous dampers corresponding to a desired system damping ratio of highway bridges, there exist, if any, few design guidelines. This is particularly true if the bridge components such as elastomeric bearings, piers and abutment possess different damping ratios, stiffnesses, and lumped masses. In this paper, the design formulas for supplemental viscous dampers to highway bridges have been derived based on the concept of ‘composite damping ratio’. The design formulas can be used to determine the damping coefficients of the dampers corresponding to a desired system damping ratio of the bridge in which different component damping ratios may be assumed for the elastomeric bearings, piers and abutments. The proposed design formulas are numerically validated by comparing the seismic responses of a three‐span bridge equipped with viscous dampers with those of the same bridge without viscous dampers but with an assigned inherent system damping ratio equal to the target system damping ratio. Copyright © 2005 John Wiley & Sons, Ltd.     

海藻乙醇提取物抗菌活性的研究

分属绿藻门、红藻门、褐藻门的海藻样品于 2 0 0 0年 5月采于山东青岛和威海附近沿海 ,将海藻样品的乙醇提取物进行薄层层析分离和抗大肠杆菌、金黄色葡萄球菌活性测定。结果表明 ,抗大肠杆菌活性较强的海藻样品有 :鸭毛藻、酸藻、松节藻和孔石莼的水相 ;抗金黄色葡萄球菌活性较强的提取物有 :鸭毛藻、海黍子、松节藻、小粘膜藻的乙酸乙酯相以及酸藻的水相。从不同门类海藻的抗菌活性看 ,褐藻最强 ,红藻次之 ,而绿藻活性最弱。薄层层析分离得到 1 6个层析带具有抗金黄色葡萄球菌活性 ,1 1个层析带具有的抗大肠杆菌性。其中褐藻门的酸藻、海黍子的 3个层析带具有很强的抗金黄色葡萄球菌活性 ,酸藻的 2个层析带也能强烈地抑制大肠杆菌的生长。在同样的实验条件下 ,对常见抗生素进行的对照实验表明 ,这 5条层析带的活性比常见的抗生素高。     

中国异枝软骨凹顶藻Chondrophycus intermedius (Yamada) Garbary et Harper的形态及解剖学

异枝凹顶藻Laurencia intermedia Yamada广泛地分布于东亚西太平洋沿岸的中国、朝鲜半岛(Nam et al. , 1984)及日本(Yoshida et al. , 1998)。在东南亚的菲律宾(Silva et al., 1987)，太平洋的斐济岛(NYeurt et al., 1996)，东非、印度次大陆及印度洋的斯里兰卡、肯尼亚、坦桑尼亚及Réunion (Silva et al., 1996)，以及西非的利比里亚、象牙海岸及加纳(Law son et al., 1987)等地均有报道。 Howe(1934)最早报道了中国的异枝凹顶藻。1962年，曾呈奎、张峻甫在“黄海西部沿岸海藻区系的温度性质”一文中也提到了该藻。1983年, 曾呈奎等在《Common seaweeds of China》中报道了黄海沿岸的异枝凹顶藻。1983年, 杭金欣等在《浙江海藻原色图谱》报道了浙江嵊山、渔山和南凫岛的异枝凹顶藻。1988年，张峻甫等也再次对该藻进行了报道。2000年，黄淑芳报道了台湾的异枝凹顶藻。     

中国马尾藻属的研究Ⅷ.扁托系的四个新种

对中国真马尾藻亚属SubgenusSargassum刺托组SectionAcanthocarPICAE团伞托序亚组SubsectionClmerulatae扁托系SeriesPlatycarpae的种类研究过程中，发现该系新种4个，它们是永兴马尾藻SargassumyongxingenseTsengetLusp．nov．．模式标本于1958年3月8日由郑树栋采自西沙群岛永兴岛，模式标本号AST58－4012；三亚马尾藻SarsassumsanyaenseTsengetLusp．nov，模式标本于1976年4月15日由曾呈奎、周显铜采自海南岛三亚市大东海，模式标本号AST76－1972；大洲马尾藻SargassumdazhouenseTsengetLuspnov，模式标本于1957年6月间日由郑树栋、夏恩湛采自海南岛三亚市大洲岛，模式标本号AST57－5615；巨囊马尾藻SargassummegalocystumTsengetLusp．nov，模式标本于1957年6月12日由郑树栋、夏恩湛采自海南岛三亚市大洲岛，模式标本号AST57－5616。4种模式标本存于中国科学院海洋研究所植物标本室。     

中国马尾藻属的研究 Ⅳ.具腺系的两个新种

对于中国马尾藻属，真马尾藻亚属滑托组Malacocarpicae（J.Ag．）Abbott，TsengetLu．总状托序亚组suhectionRacemosae,具腺系SeriesGlandulariae的种类进行了系统的研究。结果表明，中国共有具腺系3个种，除棒托马尾藻前人已经报道外，本文建立了两个新种，它们是：1．线形马尾藻，模式标本于1955年5月7日来自广东省硇洲岛，模式标本号为AST55－2259；2．钦州马尾藻，模式标本于1955年5月7日采自广西钦州湾龙门镇，模式标本号为AST55－1987。两者的模式标本均保存于中国科学院海洋研究所藻类标本室。     

Two new brown algae from the Xisha Islands,South China Sea

In our phycological trips to the Xisha Islands,Guangdong Province,South ChinaSea in 1976 and 1980,two interesting brown algae had attracted our special attention.Oneof them was a Hydroclathrus,evidently more delicate and slender than H.clathratus com-monly met with in the South China Sea region.The other was a Turbinaria,characterizedby especially small leaves.Comparative studies of the two algae with other known speciesof the two genera concerned showed sufficient differences to warrant their statuses as un-     

Slip monitoring of a dip-slope and runout simulation by the discrete element method: a case study at the Huafan University campus in northern Taiwan

Slope failure is a widely observed phenomenon in the mountainous areas in Taiwan due to rainy climatic and fragile geological conditions. Landslides easily occur after intense rainfall, especially from typhoons, and, accordingly, cause a great loss of human life and property. At the northern end of the Western Foothill belt in northern Taiwan, Huafan University is founded on a dip-slope about 20° toward the southwest composed of early Miocene alternations of sandstone and shale. Data from continuous monitoring using inclinometers and groundwater gauges reveal that 6–10 mm/month of slope creeping occurs, and a potential sliding surface is then detected about 10–40 m beneath the slope surface. To understand the potential runout process of the dip-slope failure at the campus, particle flow code 3D models based on a discrete element method are applied in this study. Results of the simulation reveal a critical value of the friction coefficient to be 0.13 and that more than 90% of the campus buildings will slide down in 100 s when the friction coefficient is reduced to half the critical value. The weakening of the shear zone due to the rise of groundwater during rainstorms is assumed to be the main factor. Some suggestions for preventing landslide disasters are to construct catchpits to drain runoff and lower the groundwater table and to install a sufficient number of ground anchors and retaining walls to stabilize the slope.     

钝顶螺旋藻C-藻蓝蛋白分子内不同基团间能量传递的研究

于１９９６年８－１２月,从钝顶螺旋藻中分离纯化Ｃ－藻蓝蛋白,并用荧光光谱法对Ｃ－藻蓝蛋白分子内不同基团间的能量传递进行研究,结果表明,Ｃ－藻蓝蛋白分子内芳香族氨基酸残基能将能量传至与脱辅基蛋白共价结合的色基,从而使色基产生相应的荧光,Ｃ－藻蓝蛋白分子２４０－２４５ｎｍ的荧光激发峰产生于二硫键,它也能将吸收的能量传至色基;同时还发现,溶液状态下的Ｃ－藻蓝蛋白分子内,色氨酸残基可能位于分子内部的疏水区