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排序方式: 共有143条查询结果,搜索用时 31 毫秒
1.
Zhenming Wang 《Journal of Earth System Science》2008,117(2):749
Microzonation is an effort to evaluate and map potential hazards found in an area, urban area in particular, that could be induced by strong ground shaking during an earthquake. These hazards include: ground motion amplification, liquefaction, and slope failure. The microzonation maps, depicting ground-motion amplification, liquefaction, and landslide potentials, can be produced if the ground motion on bedrock (input) and the site conditions are known. These maps, in combination with ground-motion hazard maps (on bedrock), can be used to develop a variety of hazard mitigation strategies such as seismic risk assessment, emergency response and preparedness, and land-use planning. However, these maps have certain limitations that result from the nature of regional mapping, data limitations, generalization, and computer modeling. These microzonations show that when strong ground shaking occurs, damage is more likely to occur, or be more severe, in the higher hazard areas. The zones shown on the hazard maps should not serve as a substitute for site-specific evaluations. 相似文献
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苏振明 《中国海洋大学学报(自然科学版)》1992,(4)
对东白令海水域双线鲽(Lepidopsetta bilineata)、太平洋拟庸鲽(Hippoglosso-ides elassodon)和阿拉斯加鲽(Pleuronectes quadrituberculata)等三种经济鲽类的捕捞群体结构和生长特性进行比较。得出结论是:(1)捕捞群体结构复杂;(2)渐近体长和渐近体重较大、寿命长、K值小;(3)雌鱼比雄鱼个体大、生长快、寿命长;(4)三种鲽类的捕捞群体结构和生长特性有明显差异。 相似文献
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基于Wishart分类器的全极化SAR图像H/α分类方法应用于海岸线分类,可区分不同海岸线类型。在聚类过程中,传统H/α-Wishart方法时常将各类聚类中心对应的散射机理混淆,使得同为单次面散射的淤泥质与砂质海岸线类别难以区分。针对此问题,提出了改进型的辅助分层分类方法。算法运用单次反射特征值相对差异度与极化总功率系数构成的二维特征空间,结合支持向量机得到最优分界判据,以分离初始分类结果中混淆的淤泥质与砂质海岸线。实验表明,改进方法能够有效区分淤泥质与砂质岸线,分类混淆矩阵对应kappa系数由0.794提升至0.853,分类识别率得到显著提高。 相似文献
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A total of 400 yeast strains from seawater, sediments, saltern mud, marine fish guts, and marine algae were obtained. The
protease activity of the yeast cultures was estimated, after which four strains (HN3.11, N11b, YF04C and HN4.9) capable of
secreting extracellular alkaline protease were isolated. The isolated strains were identified as Aureobasidium pullulans, Yarrowia lipolytica, Issatchenkia orientalis and Cryptococcus cf. aureus. The optimal pH of the protease activity produced by strains HN3.11, YF04C, and HN4.9 was 9.0, while that of the protease
produced by strain N11b was 10.0. The optimal temperature for protease activity was 45°C for strains HN3.11, N11b, and YF04C,
and 50°C for strain HN4.9. After digestion of shrimp (Penaeus vannamei) protein and spirulina (Arthospira platensis) protein with the four crude alkaline proteases, the filtrate from spirulina (Arthrospira platensis) powder digested by the crude alkaline protease of strain HN3.11 was found to have the highest antioxidant activity (61.4%)
and the highest angiotensin I converting enzyme (ACE)-inhibitory activities (68.4%). The other filtrates had much lower antioxidant
activity and ACE-inhibitory activities. 相似文献
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1博兴县新农村建设中存在的问题(1)村庄建设闲置浪费土地严重。博兴县共有行政村448个,由于历史原因,大部分村布局松散,居住零乱,闲置浪费土地多。据调查,全县村庄建设用地面积7880.75hm2,村人均占有256m2,远远超出国家规定的人均最高150m2的标准。特别是县域北部地区,村庄用地粗放,闲置浪费土地现象普遍存在。随着工业化、城镇化进程加快,村民外出经商、进城创业居住的明显增多,农村中出现了较多的闲置房。(2)村庄建设违法占地逐渐增多。近年来,博兴县个体经济快速发展,用地需求也大量增加,部分村庄建设建新不拆旧、超占、多占宅基地;乱占耕地,尤其是在沿街沿路交通便利地段,违法建起了大量商住两用房。 相似文献
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Characterization of a mutant of <Emphasis Type="Italic">Alteromonas aurantia</Emphasis> A18 and its application in mariculture 总被引:1,自引:0,他引:1
Mutant J61321 with enhanced siderophore production of Alteromonas aurantia AI8 was obtained after a series of chemical-physical mutageneses. It was found that the antibacterial activity against Vibrio anguillarum W-1 and siderophore production of the mutant were higher than those by the original strain A 18 which had been used in mariculture. The results of the specific assay(Csaky and Arnow methods) of siderophore showed that the sidrophore with hydroxamate group was produced by mutant J61321 and the original strain A 18, respectively, while the siderophore with catechol group was yielded by strain W-1 (Aibrio anguillarum). Meanwhile, the siderophore yield, antibacterial activity and anti-chelator activity of strain J61321 were higher than those of its parent strain A 18. 相似文献
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