浅析混凝土空心砌块复合墙体的保温性能

介绍了混凝土空心砌块复合墙体的构造及热工性能，并与普通砖混结构做对比，得出该砌块复合墙体的夹心保温方式较通常砌体墙体的内，外保温方式有很多优越性，是符合我国国情的一种理想的外墙保温方式的结论，在此基础上就混凝土空心砌块的推广应用提出了一些建议。     

空心板梁桥"单板受力"病害机理及其加固处治研究

首先建立了6种跨度空心板梁桥的梁单元模型,分析得出荷载横向分布规律.通过对一10 m跨度桥梁实体模型的数值分析,讨论了桥梁"单板受力"病害产生的原因,并提出了4种加固方案.然后通过比较分析底板竖向位移、横向应力以及等效应力;综合各方案的优缺点,确定了最优加固方案,为"单板受力"病害的防治提供了理论依据.最后提出了增加结构横向刚度、保证施工质量等措施,以期能有效地防治"单板受力"病害.     

装配式斜交空心板桥受力特性分析

运用空间板壳有限元法,对装配式斜交空心板桥弹性阶段的受力特性进行全面分析．计算装配式斜交空心板桥的内力影响面,得到内力的控制截面．同时对比分析了装配式斜交空心板桥、整体式斜交空心板桥与装配式正交空心板桥的内力、支座反力以及变形的特点,为装配式斜交空心板桥的设计提出了若干值得注意的问题及其理论依据．     

中空SiO2微球对重金属Cd(II)的吸附研究

采用壳上具有纳米孔的中空SiO2微球从溶液中吸附重金属Cd(II)离子,研究了被吸附溶液的pH值、Cd(II)离子初始浓度、吸附时间等对吸附Cd(II)离子的影响。结果表明,壳上具有纳米孔的中空SiO2微球可用于从溶液中吸附Cd(II)离子。在pH>3的弱酸性溶液中比在pH≤3的酸性条件下中空SiO2微球吸附Cd(II)离子的量要大得多。Cd(II)离子初始浓度小于0.4 mol.L-1时,Cd吸附量随Cd(II)离子初始浓度的影响较小,进一步增大Cd(II)离子初始浓度,吸附量大幅攀升。     

一种改进的低密度薄壁中空微球预混料均匀性及密度表征方法

基于多级粉体堆积理论，建立了低密度薄壁中空微球预混料的堆积模型和理论密度计算方法；基于微球混合物的图像色彩亮度和混合均匀性存在一定映射关系，使用图像二值法进行图像采集处理，并引入综合分散度表征混合均匀度；设计了低密度薄壁中空微球预混料的密度及混合均匀性测量系统，通过PLC可实现压力和位移的可控精确测量。使用本测量系统对微球预混料进行了10组实验的密度值测定，结果表明：测得的预混料的平均密度为0.431 2 g/cm³，预混料的理论密度为0.428 2 g/cm³；密度测定的相对标准差为0.25%，与手工称量瓶法相比，本测量系统的密度重复测试精度提高了1.12倍，且平均密度更接近理论密度。测定了不同混合程度的3种预混料的混合均匀性，结果表明：随着预混料由粗混到精混，其对应的综合分散度逐渐增大并接近理想样品，采用本文算法得到的预混料的综合分散度量化数值能够反映预混料的混合均匀度。     

Novel porous ceramic with high strength and thermal performance using MA hollow spheres

The objective of this work is to obtain a multifunctional porous ceramic material at low cost with improved properties and that can be used in many applications like: thermal and acoustic insulation, refractory support and hot gas filtration elements. To that end, a novel facile strategy to fabricate porous ceramics by foaming and pore-forming agent methods using magnesia-aluminum spinel hollow spheres (MASHSs) was reported for the first time, in which calcium aluminate cement (CAC) served as high-temperature binder. The influence of temperature ranging from 1500 ?°C to 1700 ?°C on the thermal conductivity, porosity and mechanical strength were investigated. The results show that, the obtained MASHSs ceramic exhibits high porosity (67.2–71.9%) and thermal conductivity (0.18–0.38 ?W/mK), and compressive strength (6.1–17.1 ?MPa), which is mainly due to the change in crack directions and microstructure optimization with the prolong of firing temperature. The crack directions changed from the surface of MASHSs to the interior MASHSs, which consumes more crack energy, and thus leading to the excellent mechanical performance. What is more, the introduction of MASHSs makes it difficult to lose heat at elevated temperature, and thereby improving the thermal conductivity of materials.     

Cu2O-templated fabrication of Ni(OH)2·0.75H2O hollow tubes for electrocatalytic oxygen evolution reaction

Cu₂O is an ideal template material for the preparation of transition metal hydroxide/oxyhydroxides with oxygen evolution reaction (OER) enhanced catalytic performance. Here, inspired by Pearson's principle, Cu₂O wires were prepared and used as a sacrificial template to prepare Ni(OH)₂·0.75H₂O hollow tubes (Ni(OH)₂ HTs) with highly improved surface roughness. Benefiting from unique structural advantages, the Ni(OH)₂ HTs showed excellent catalytic activity, rapid kinetics and a long-term stability as the OER catalyst, where an overpotential of only 207 ?mV was required to drive a current density of 10 ?mA ?cm^?2, an ideal kinetics with a Tafel slope as 79.8 ?mV dec^?1 was calculated, and no obvious attenuation in chronoamperometry was discovered after operation for 24 ?h. This paper provides a novel template-assisted strategy to prepare high-performance transition metal-based OER catalysts possessing hollow and tubular structures.