RECENT ADVANCES IN AMINES AS SEPARATING AGENTS FOR METAL IONS

ABSTRACT

In this article those aspects of the application of amines in metal ion separation during the last two decades which could be regarded as new facets or as clarifying earlier concepts have been briefly dealt with. This includes work with diammonium extractants and a comparison with their monocationic analogues and new approaches to explain the different secondary effects. In addition more emphasis has been placed on the neutral N-donor action of amines and their application towards metal ion specificity. The importance of a thorough understanding of the basic properties of the amine and the metal ion were indicated for the development of new metal ion specific separating agents.     

Problems and challenges of urban water resources development

A simulation model, WASHMO, is used to illustrate how urbanization influenced flood peaks and volumes for the 1:50 year event in the Palmiet River. The impact of urban stormwater on the channel and the water quality of urban rivers are discussed. Suggestions are made for better urban stormwater control.     

Al—5Ti—B变质高锌铝合金的组织和性能

研究了Al-5Ti-B变质高锌铝合金的组织和性能。金属型铝合金组织不发达的粗大α树枝晶，晶界上杂乱分布着大块状或长条状的富硅相及其他相。经钠盐精炼和0．08％Ti变质后，合金生长形状发生巨大变化，α树枝晶发达而细小，二次枝晶臂间距显著减小；硅相和其他晶间相变为球状或细短条状且均匀弥散分布在α枝晶的晶界上；晶间组织增多，变质后，抗拉强度显著提高，塑性也明显改善。     

核一级容器钢508-3的动态和静态断裂韧度

核一级部件的断裂韧度要求反映在ASME和RCC－M规范中，即KIR－（T－RTNDT）基准曲线。KIP包括KIa,KId和KIc^J。KIc^J的测试国内外已有标准方法，而KIa的测试只有美国公布了正工标准，KId的测试国内外没有标准方法可循。因此，为研究核电材料断裂韧度，首先建立了相应的测试方法，在此基础上试验了国产核一级容器钢508－3的动、静态断裂韧度KIa,KId,KIc，获得了不同温度下的数据，并与ASME和RCC－M规范中的基准曲线作了比较。结果表明，国产508－3钢的动、静态断裂韧度能满足核一级部件的要求。     

Grating lobes caused by parallel-plate polariser

An unexpected high-level sidelobe was encountered when a parallel-plate polariser was fitted to a slotted waveguide array. The phenomenon is explained using grating lobe theory and linear near-field measurements. A technique to suppress the grating lobe is proposed.     

Pore-scale derivation of the Ergun equation to enhance its adaptability and generalization

The empirical nature of the well-known Ergun equation for prediction of the permeability of granular materials inhibits the straightforward generalization to other geometries of the pore space and non-Newtonian effects of traversing fluids. In this paper the results are discussed of a pore-scale model that can be regarded as qualitative and quantitative proof of the Ergun equation. The pore-scale model has superior adaptive capabilities and also allows investigation of the porosity dependence of the empirical coefficients of the Ergun equation. Some advantages, based on physical grounds, of the pore-scale model are outlined.     

在Web应用中施展Ajax技术的研究

AJAX技术允许在创建和使用B／S应用的时候，完全实现GUI技术。本文对Ajax技术进行典型化归纳，总结出一个简单的Ajax技术标准，在Web应用中，增加“HttpRequest后台通道”、“业务函数”和“DIV块内参数合成”的处理，利用CSS标记控制写出更清晰，更具移植性的B／S应用。     

酚酸结构对酚酸-g-聚甘露糖醛酸抗氧化性能的影响

以海藻酸钠水解产物聚甘露糖醛酸(PM)为原料,通过聚甘露糖醛酸-乙二胺(PM-EDA)中间体与酚酸接枝共聚,制备了8种PM的酚酸(PA)接枝共聚物酚酸-g-聚甘露糖醛酸(PA-g-PM),并探究了PA结构对8种PA-g-PM抗氧化活性的影响。在n_PM:n_EDA=1:1.5,PM与两种活化剂碳二亚胺(EDC)、N-羟基琥珀酰亚胺(NHS)的摩尔比1:2:1,活化0 h,pH 8.0条件下,反应24 h,获得最高取代度(17.27%)的PM-EDA。PM的PA-g-PM接枝率在4.171±0.16 ~ 8.880±0.32 mg GA/g之间。UV-vis、FT-IR、XRD表征证实酚酸已成功接枝到PM上获得PA-g-PM。相比PM,8种PA-g-PM的对DPPH的清除率和对铁的还原力均显著提升。PA-g-PM的抗氧化性能与其中的酚羟基个数呈正相关关系,对位酚羟基PA-g-PM的抗氧化性能优于邻位酚羟基PA-g-PM的抗氧化性能,PA-g-PM中的酚羟基被甲氧基取代其抗氧化性能减弱。以期本研究结果为海藻酸钠在食品、化妆品、医药等行业高值开发利用奠定理论基础。     

一种基于方向元件的微网保护控制方案

随着新能源利用的不断提高,微电网受到了越来越多的关注。在微网孤岛运行结构特点研究基础上,提出了一种基于负序方向元件的微网孤岛运行保护方案。该方案只需比较保护安装处的负序电压与电流的相角差即可判别故障方向,且具有很好的抗过渡电阻能力。基于PSCAD/EMTDC搭建的仿真模型验证了结论的正确性。     

全麻下单导丝引导Y型气道支架置入术治疗复杂气管疾病6例

【摘要】 目的 探讨在全身麻醉下采用单导丝引导Y型气道支架置入的方法和临床应用。方法 接受气道Y型支架治疗复杂气管疾病患者6例,其中气管胸膜瘘1例,食管-气管瘘2例,气道复合型狭窄3例。全身麻醉后在DSA监视下对6例患者置入气道Y型支架。结果 6例患者共置入Y型气道支架6枚,均为单导丝引导置入,其中1例支架右侧分支误入右肺上叶支气管内,余5例支架置入均一次获得成功。结论 全麻下Y型气道支架置入术能有效封堵支气管残端胸膜瘘、左主支气管食管瘘,能快速有效解除气管隆突区复合性气道狭窄,近期疗效显著,手术安全、可靠,单导丝引导置入技术操作相对于双导丝引导置入技术操作简单、快速有效、值得推广应用。