基于仿生防护技术的海底管线悬空治理研究

针对海底管线悬空对海洋油气田安全生产的严重威胁及其对海洋环境构成的重大隐患,文章以海底管线周围的局部冲刷及其冲刷防护与控制技术为研究对象,从海底管线冲刷机理入手,分析了管线一次悬空和二次悬空的原因,从模型实验和工程实践两方面开展仿生防护技术治理海底管线悬空研究,利用高分子材料仿生草叶片的柔性黏滞阻尼作用,减缓流速,降低水流的携沙能力,最终达到固沙、填沙、保护管线的目的。     

安全壳在事故情况下的完整性分析

现有的安全壳完整性分析,主要针对设计基准事故条件下安全壳内部压力的响应进行分析。而AP1000的安全壳事故承压分析不仅包括设计基准事故,还包括严重事故情况下的完整性分析。安全壳完整性分析的过程中所使用的程序、设定的条件都是较为保守的,这就使得安全壳有很大裕度。而在相关试验数据愈加充分并且人们对相关事故进程与机理的认知有较大提高的条件下,使用最佳估算来对安全壳完整性进行分析能够在保证基本裕度的条件下,较合理地减小其设计保守性,为今后我国更大功率的非能动核电厂安全壳设计与建造提供方便。     

Organic and metallic pollutants in water treatment and natural wetlands: a review

A literature review shows that more than 500 compounds occur in wetlands, and also that wetlands are suitable for removing these compounds. There are, however, obvious pitfalls for treatment wetlands, the most important being the maintenance of the hydraulic capacity and the detention time. Treatment wetlands should have an adapted design to target specific compounds. Aquatic plants and soils are suitable for wastewater treatment with a high capacity of removing nutrients and other substances through uptake, sorption and microbiological degradation. The heavy metals Cd, Cu, Fe, Ni and Pb were found to exceed limit values. The studies revealed high values of phenol and SO(4). No samples showed concentrations in sediments exceeding limit values, but fish samples showed concentrations of Hg exceeding the limit for fish sold in the European Union (EU). The main route of metal uptake in aquatic plants was through the roots in emergent and surface floating plants, whereas in submerged plants roots and leaves take part in removing heavy metals and nutrients. Submerged rooted plants have metal uptake potential from water as well as sediments, whereas rootless plants extracted metals rapidly only from water. Caution is needed about the use of SSF CWs (subsurface flow constructed wetlands) for the treatment of metal-contaminated industrial wastewater as metals are shifted to another environmental compartment, and stable redox conditions are required to ensure long-term efficiency. Mercury is one of the most toxic heavy metals and wetlands have been shown to be a source of methylmercury. Methyl Hg concentrations are typically approximately 15% of Hgt (total mercury). In wetlands polycyclic aromatic hydrocarbons (PAH), bisphenol A, BTEX, hydrocarbons including diesel range organics, glycol, dichlorodiphenyltrichloroethane (DDT), polychlorinated biphenyls (PCB), cyanide, benzene, chlorophenols and formaldehyde were found to exceed limit values. In sediments only PAH and PCB were found exceeding limit values. The pesticides found above limit values were atrazine, simazine, terbutylazine, metolachlor, mecoprop, endosulfan, chlorfenvinphos and diuron. There are few water quality limit values of these compounds, except for some well-known endocrine disrupters such as nonylphenol, phtalates, etc.     

甲岩水电站右岸泄洪洞旋流竖井Ⅱ期开挖支护施工

介绍甲岩水电站右岸泄洪洞旋流竖井在Ⅱ期开挖、支护施工阶段可选用几种施工方案。通过对几种施工方案的可行性、经济性比较,选择了从竖井上部用电动单梁起重机悬挂渣斗出渣、起吊施工材料设备的方案,在施工过程中起重机运行良好,用107 d完成右岸泄洪洞Ⅱ期开挖支护施工,比原计划提前了15 d。     

毛诃子中总多酚的提取工艺研究

目的 比较不同提取条件对毛诃子提取物多酚含量的影响。方法 采用超声辅助溶剂萃取法, 利用响应曲面实验和正交实验单因素考察乙醇浓度, 料液比、提取时间和提取功率对提取物中多酚含量影响, 探索最佳提取工艺。结果 乙醇浓度为主要因素, 其次是提取时间, 再次是料液比, 而提取功率影响最小。乙醇55%、料液比1:38 g/mL、提取时间为12 min、提取功率为300 W时提取物中多酚含量达最高。结论 本研究确定了毛诃子中多酚的提取工艺; 响应曲面试验与正交试验相比更安全、可靠、精确。     

基于琼脂糖和纳米金的电流型免疫传感器快速检测副溶血性弧菌

将HRP-anti-VP掺杂于琼脂糖和纳米金中并修饰于丝网印刷电极表面,从而制备副溶血性弧菌免疫电极.采用循环伏安法表征免疫电极和监测酶促反应,根据还原电流的变化来定量测定副溶血性弧菌.在优化的实验条件下,免疫电极线性检测范围为105～109 cfu/mL,检出限为7.4×104 cfu/mL(S/N=3).该免疫电极具备较好的特异性、重现性(RSD＜6%)、稳定性(一周后电流响应为初始值的91%)和准确性(与ELISA符合率为97.5%),可初步用于副溶血性弧菌的快速筛检.     

褒河石门水库“81.8”洪水重现期的考证

一、工程概况 石门水利枢纽工程位于汉江支流褒河峡谷出口以上1.8公里处。南距汉中18公里。 本工程是以灌溉为主、结合发电等综合利用效益的大型水利枢纽,为褒河梯级开发的第     

汕汾高速公路典型软基路段预制砼管桩处理效果评价

在软基地区修筑高速公路,路基的沉降和稳定是制约施工工期和行车安全的两大基本问题,汕汾高速公路的典型软基路段按照常规手段处理后,路基填筑至设计高度一半,出现裂缝,果断地采取了部分卸载-等待-再加载的措施,再加载后裂缝再度出现.经多方反复论证,采取压入预制砼管桩的处理方案,效果良好,本文对此进行介绍,并从软基监测的角度进行评价.     

CYB-30型液力变矩器的改进

我厂生产的ZLM30装载机,在传动系中所采用的CYB-30型液力变矩器是参考国外样机试制的,如图1所示。经过几年运行,发现该变矩器出现下列几个问题: