南沙港区陆域吹填工程真空预压软基处理技术

介绍在南沙港区真空预压加固施工中,采用土工织物对吹填淤泥进行表面处理、水平排水板处理含泥量高的砂垫层及长短搅拌墙相结合的密封技术     

某洪渡槽裂缝原因浅析及处理措施

通过对某排洪渡槽工程主梁裂缝情况的资料进行搜集整理,分析了裂缝产生的诱因及其对渡槽使用产生的危害,并提出了相应的裂缝补救及预防措施,从而为渡槽工程中裂缝的防治积累了经验。     

Surface characteristics of chemical conversion coating for Mg-Al alloy

The chemical conversion coating was formed on Mg alloy for low cost and harmlessness in environment by using the colloidal silica as the main component. The film formed at 298 K was thick, which was thought to be the combination of Si and O. In salt spray test, the ratio of black rust on the specimen that did not conducted chemical conversion treatment was five times or more than those of the chemical conversion treated specimen. The film of chemical conversion coating produced by alkali treatment process was thinner than the specimen produced in basic chemical conversion treatment solution.     

交变磁处理对金刚石锯片切割性能的影响

选用不同的工艺参数在交变磁场中对金刚石锯片通磁处理,通过对磁处理试件和未磁处理试件的对比切割试验,研究了交变磁处理对金刚石锯片切割性能的影响.研究结果表明:交变磁处理提高了胎体对金刚石的机械把持力,数据统计显示,磁处理锯片金刚石颗粒的脱落率低,参与切割的金刚石数目多,金刚石的有效利用率得到提高;从切割效果来看,交变磁场能够有效提高金刚石锯片的切割性能,但磁处理温度条件对锯片的切割性能有一定的影响;试验优选的磁处理工艺条件为:300 ℃、50 Hz、1 T、60 min,在该工艺条件下,锯片的使用寿命提高46.3%,切割速度提高13.1%;断口组织形貌分析显示,交变磁处理后试件胎体的组织晶粒细小,晶粒细化是金刚石锯片切割性能提高的根本原因.     

Optimising the T6 heat treatment for gravity cast AlSi7MgCu0.5 alloy V8 cylinder heads

Alternatives to the Standard T6 heat treatment that relied on a 5-h solution heat treatment at 490 °C were investigated in effort to reduce the heat treatment cycle time for the manufacture of AlSi7MgCu0.5 alloy V8 cylinder heads without sacrificing the mechanical properties while providing extra capacity in the heat treatment plant. The optimum T6 heat treatment process was identified to be a SHT at 545 °C for 1 h followed by ageing treatment at 180 °C for 3 h. Mechanical properties of the cylinder heads thus manufactured were markedly superior while the total heat treatment duration was reduced by 2.5 h with respect to the Standard heat treatment. This implied a capacity increase of %61 and rendered the undertaking of a major customer order possible.     

某地裂缝特征、成因及防治措施

地裂缝按其成因类型分构造裂缝和非构造裂缝，地裂缝是某地最大的地表地质灾害，迄今为止，已发现了5条地裂缝，它们均为活动裂缝，而且给当地人民造成很大的灾害，通过某地裂缝的现场多次调研，对裂缝的特征有了一定了解，在此基础上对其成因进行了初步研究，并提出了相应的处理措施，该裂缝的发展及其危害已引起了当地的高度重视。     

环境矿物改性及对污水中氨氮的吸附试验研究

为了探索污水处理中氨氮的优良吸附剂,对环境矿物沸石、膨润土和粉煤灰分别进行了酸、碱、盐、热改性,并对氨氮的吸附效果进行了对比试验研究。结果表明:5%钠改性沸石对氨氮吸附效果最好;影响5%钠改性沸石吸附氨氮的主次顺序为:投加量吸附时间p H值转速;当氨氮含量为30 mg/L时,5%钠改性沸石在投加量为20 g/L、吸附时间120 min、p H值为8、转速150 r/min的条件下,对氨氮去除效果最好可达88.34%;钠改性沸石对氨氮的吸附机理为:Na+置换了沸石中半径较大的阳离子,使沸石孔道的有效空间变大,空间位阻变小,内扩散速度加快,比表面积加大,吸附能力增强。离子交换后的钠改性沸石电负性增强,且Na+易被NH4+交换,因而NH4+可被钠改性沸石有效去除;5%钠改性沸石对氨氮的吸附符合Freundlich模型,是吸附氨氮的优良吸附剂。     

易自燃特厚煤层瓦斯综合治理技术

结合千秋煤矿实际情况，介绍了易自燃特厚煤层瓦斯综合治理技术。经过实践，应用效果良好。     

表面酸处理对蓝晶石可浮性的影响及机理研究

研究了盐酸处理对蓝晶石可浮性的影响。发现酸处理能使蓝晶石的可浮性显著提高，而老化使蓝晶石的可浮性降低。用量子化学计算和Ｘ射线光电子能谱研究了蓝晶石的表面性质，认为在盐酸溶液中蓝晶石表面铝组分优先溶解，在蓝晶石表面产生空穴。提出了矿物表面存在两种吸附活性中心假说，即空穴型吸附活性中心和质点型吸附活性中心。应用这一假说成功地解释了不同表面状况蓝晶石的可浮性规律。