Durability quality control for the marine bridge concrete structure of Xiamen Yanwu Bridge

本文通过厦门演武大桥工程实例,对跨海桥梁混凝土结构耐久性的质量控制进行了探讨。研究认为,通过采用环氧树脂涂层钢筋、高性能混凝土、防腐涂料外涂层保护以及加强施工过程中的质量管理等多种有效措施,可以实现对跨海桥梁混凝土结构耐久性的质量控制。This essay discusses the durability quality control for marine bridge concrete structure combined with the engineering example of Xiamen Yanwu Bridge.Disquisitions show that by using the Reinforced epoxy coating and HPC,Anti-corrosion coating,and reinforce the measures such as quality management during the construction,we can realize the durability quality control for marine bridge concrete structure

医院感染多重耐药菌分布及耐药性分析

目的了解医院感染多重耐药菌分布及耐药性分析,为临床诊疗提供依据。方法 25 618例临床感染标本分离株培养鉴定后,监测常见分离菌的多重耐药菌株(MdrO)。结果 1 087株分离菌以革兰阴性菌925株为主,革兰阳性菌162株。革兰阴性菌中分离率前5位分别是肺炎克雷伯菌、大肠埃希菌、铜绿假单胞菌、鲍曼不动杆菌、阴沟肠杆菌。革兰阳性菌中分离率前5位分别是金黄色葡萄球菌、凝固酶阴性葡萄球菌、肺炎链球菌、屎肠球菌、粪肠球菌。大肠埃希菌、肺炎克雷伯菌产超广谱β-内酰胺酶(ESblS)株的检出率分别为75.53%、37.14%;金黄色葡萄球菌中耐甲氧西林的金黄色葡萄球菌(MrSA)的检出率为78.20%,凝固酶阴性葡萄球菌中耐甲氧西林的凝固酶阴性葡萄球菌(MrCnS)的检出率为84.60%。13株屎肠球菌中发现3株万古霉素耐药株(VrE)。结论医院感染多重耐药菌分布主要以革兰氏阴性杆菌为主,其次是革兰氏阳性球菌。MdrO的增多是医院面临的重要问题,在临床上应改进治疗手段,合理使用抗菌药物,减少MdrO的产生和播散

海洋细菌作用下海水中铬化学形态的转化

于外加Cr（Ⅳ）和Cr（Ⅲ）的天然海水中接种海洋细菌，充氧条件下培养。在细菌对数生长期，大部分Cr（Ⅳ）被还原为Cr（Ⅲ）继而转化为有机铬。在稳定期，有机铬为溶解铬的主要形态，在无菌控制实验中，Cr（Ⅳ）和Cr（Ⅲ）浓度基本不随培养时间变化。说明在没有海洋细菌活动参与下，水中铬形态转化难以进行。实验结果为天然海水中溶解态铬的热力学不平衡状态提供部分可能的解释

硒在海洋浮游植物生化组分中的分布

硒在海洋浮游植物生化组分中的分布杨逸萍，李河典，胡明辉（厦门大学海洋学系）关键词硒，海洋浮游植物，生化组分前言硒为中等生物制约元素。海洋浮游植物对硒的富集系数高达103~104［1］.硒沿海洋食物链的传递［1~4］表明硒在生物体内可能被结合在细胞原生...国家自然科学基

Durability quality control of concrete structure for marine bridge

对影响跨海桥梁混凝土结构耐久性的主要因素进行了分析,在此基础上,结合厦门演武大桥工程实例,对跨海桥梁混凝土结构耐久性的质量控制进行了探讨。研究认为,跨海桥梁混凝土结构耐久性的质量控制是一个涉及材料、结构设计与施工等多方面的综合难题。通过采用环氧树脂涂层钢筋、高性能混凝土、防腐涂料外涂层保护以及加强施工过程中的质量管理等多种有效措施,可以实现对跨海桥梁混凝土结构耐久性的质量控制。The main factors that affects the durability of concrete structure for marine bridge,is analyzed based on this,combined with the engi- neering example of Xiamen Yanwu Bridge,the durability quality control of concrete structure for marine bridge is discussed.Disquisitions show that the durability quality control of marine bridge is a comprehensive issue that refers to many aspects such as material,structure design and con- struction.By using the reinforced epoxy coating and HPC,anti-corrosion coating,and reinforcing measures such as quality management during the construction,the durability quality control of marine bridge is realized.国家自然科学基金重大国际合作研究项目(2005CCA06700

Statistical study of trace elemental concentrations in major types oforganisms from typical Chinese coastal waters

研究了微量元素Fe、Mn、Zn、Cu、Sr、Ba在我国典型海域主要生物类别中的概率分布特征,并与常量元素Ca、Mg进行了比较。结果表明,微量元素的概率分布曲线具正偏态性质,概率分布类型大多为对数正态分布或近似对数正态分布,表明对某一特定微量元素,大多数生物体中的含量都比较低,只有个别生物有不成比例的高含量。常量元素Ca与微量元素相似,表现为对数正态分布,而Mg却具正态分布特征。本文给出了我国典型海域生物体中元素含量的总体分布特征。The probability distribution of the trace elements Fe, Mn, Zn, Cu, Sr and Ba in the marine organisms collected from the typical Chinese coastal water swere studied and compared with those of major elements Ca and Mg. All the distributions for the trace elements in macrophytes, benthic molluscs, crustaceans, cephalopods and different tissues in the fish (muscle, liver and bone) were nearly found to show the positive skewness, and a relatively large number of the marine organisms with low concentrations for the element and only a few organisms with disproportionately high concentrations. Their distribution types were generally logarithmic normal distribution or nearly logarithmic normal distribution. Distribution of Ca was similar to the trace elements, while Mg the normal distribution. Average concentrations of the major elements in the organisms were calculated based on their probability distributions.教育部博士学科重点项目(96038412

Key Technology for Improving Resistance Against Chloride Ion Penetration of Marine Concrete

为了提高海工混凝土的抗氯离子渗透性,从原材料选择与配合比优化设计方面探讨了提高海工混凝土抗氯离子渗透性的关键技术,并对福建厦门杏林湾九天湖大桥工程案例进行了分析。结果表明,将Ⅱ级粉煤灰、矿粉和混凝土抗氯离子增强剂按一定比例复配,对混凝土配合比进行优化设计,能够有效提高海工混凝土的抗氯离子渗透性。In order to improve resistance against chloride ion penetration of marine concrete,the key technology for improving resistance against chloride ion penetration of marine concrete was discussed from the choice of raw materials and the mixture proportion design,and the engineering example of Xiamen Xinglin Bay Jiutianhu Bridge of Fujian Province was analyzed.The results show that confecting Ⅱ fly ash,slag powder and concrete strengthening agent on resistance against chloride ion penetration in a certain proportion and optimizing the mixture proportion design of concrete,can effectively improve the resistance against chloride ion penetration of marine concrete.国家自然科学基金重大国际合作研究项目(2005CCA06700);福建省建设厅科技计划项目(2005-2-2

Electroless copper plating on ceramics

为提高化学镀铜液的稳定性 ,在化学镀铜液中加入亚铁氰化钾和a ,a’ -联吡啶作为添加剂。研究了温度与陶瓷基体上化学镀铜沉积速度的关系 ,计算出铜沉积的活化能。当镀液中含有亚铁氰化钾或a ,a’ -联吡啶时 ,铜沉积活化能提高 ,铜沉积速率降低 ,镀铜层外观及镀液稳定性均得到改善。此外 ,镀液中同时含有亚铁氰化钾和a ,a’ -联吡啶时 ,镀液、镀层性能得到进一步提高。Potassium ferrocyanide and a,a'-dipyridine were added in electroless copper plating bath to improve the bath stability. Relationship between temperature and copper deposition rate on ceramics was studied, and the activated energy of copper deposition was calculated With the addition of potassium ferrocyanide and a, a'-dipyridine, the activated energy of copper deposition increased and copper deposition rate decreased, electroless copper plating is improved in deposit appearance and bath stability. Furthermore, better results can be obtained provided that potassium ferrocyanide and a,a'-dipyridine are used in combination

Studies on the Formation Mechanism of Expanded Graphite by Electrolytic Oxidation Method

采用现代测试方法对电解氧化法制备的膨胀石墨各阶段产物进行了表征 ,对其形成机理作了一些探讨。结果证实 ,在氧化过程中 ,层间表面的石墨被氧化后 ,与嵌入层间的H2 SO4、H2 O等生成层间化合物 ,该化合物瞬间受高热而分解 ,产生的推力使石墨沿C轴方向膨胀 ,而层平面碳 -碳结构未被破坏。The expanded graphite was prepared by electrolytic oxidation.The nature graphite(NG)、oxided graphite (OG) and expanded graphite means of (EG) is characterized by scanning electron microscopy SEM.X-Ray diffraction (XRD) and transmision electron microscope (TEM).The results show that the surface graphite in interlayer is oxided first,and then sulphate_graphite intercalation compounds is formed with H 2SO 4 and H 2O intercalated in the interlayer.It expands along c_axie when heated at 1000℃ in a twinkling.The C-C structure on the layer does not destroy.福建省自然科学基金!资助项目 (E970 1 1