关于全国推广洪水风险图的认识与设想

近年来，随着我国社会经济的加速发展，水灾损失也在急剧增长。洪水风险区域内人口资产密度提高，而经济发展中缺乏水患意识，减灾措施不足，以及总体上防洪保护标准偏低等，是水灾损失剧增的重要原因。为了扭转被动局面，国家防汛抗旱总指挥部决定在全国推广洪水风险图。世界各国防洪形势国情不同，洪水风险图的绘制目的与风险图的内容和表达形式也有显著差异。本文通过基本国情的分析和中外风险图绘制目的与必备内容的比较，探讨适合于我国推广的洪水风险图形式。     

腐蚀环境下飞机结构日历寿命研究现状与关键技术问题

介绍了军用飞机日历寿命研究的技术背景和国内外同类研究概况以及存在的问题。重点对腐蚀环境下飞机结构加速腐蚀试验技术、防腐涂层腐蚀损伤评定技术、腐蚀损伤和疲劳寿命的分布特性及其变化规律、腐蚀当量关系和日历寿命理论分析方法等几个关键问题及其技术途径进行了阐述和探讨。     

Preparation and characterization of modified dual network dust suppression gel based on sodium alginate and soluble starch

Aiming at the problems of complex environment and serious dust pollution in large open-pit coal yards, a dust suppression gel with a dual network structure was prepared by modifying the soluble starch and sodium alginate with iron ions. The changes of functional groups, thermal stability, and morphology structure before and after the reaction were analyzed by FTIR, TG-DSC, and SEM, and the formation mechanism of the dual network was revealed by XPS. Furthermore, the water absorption and water retention experiments proved that the dual network structure is more conducive to water retention than the single-layer network. According to molecular dynamics simulations and contact angle experiments, gel and adsorbed water molecules can approach coal dust molecules on their own to contact, wet, and combine with coal dust. The adhesion test proved that the dust suppression gel with iron ions had better adhesion to dust. The anti-freezing test shows that the dust suppression gel has good anti-freezing performance. The antifreeze test shows that the dust suppression gel still has excellent freeze–thaw resistance at the test temperature of??-20℃. The mechanical property test shows that the dust suppressant gel can prevent the product from being damaged by external force. The acid and alkali resistance experiments showed that the acid and alkali resistance of the gel was improved under the condition of iron ion modification, and the flying of coal powder was effectively prevented. This research provides a new theoretical idea for coal dust control in complex environment.