湿法磷酸萃取尾气中氟硅资源回收利用工业化技术研究

湿法磷酸萃取尾气中氟硅资源回收利用装置采用一氟洗涤吸收塔、文丘里洗涤器、二氟洗涤吸收塔、三氟洗涤吸收塔、尾气洗涤吸收塔五级逆流洗涤方式。装置停车清理周期≥60 d,且清理时间≤1 d。装置具备联产Na_2SiF_6和无水HF功能,以及回收利用尾气中碘和硅资源功能。装置氟硅酸产量达14 kt/a(以H_2SiF_6计),硅胶产量达2 900 t/a(以SiO_2计),同时可减少污水站石灰消耗量4 861.11 t/a。此外,该装置尾气排放完全满足GB 16297—1996二级标准限值要求。     

Fiber‐draw‐induced elongation and break‐up of particles inside the core of a silica‐based optical fiber

Particles in the core of optical fibers are widely studied to tailor or to improve optical properties. The analysis of nanoparticles embedded in silica‐based optical fiber allowed new observations of the evolution of amorphous particles during fiber drawing. Even at the nanoscale, competition between viscous stresses and surface tension on the particles induces elongation and even break‐up of particles during the process. Indeed, particles between 140 and 200 nm diameter inside the preform can break up in fragments with diameters down to 60 nm inside the drawn fiber. Break‐up of particles appears as a new “top‐down” strategy to produce small particles. These observations are promising for micro/nanostructured and multiphasic optical fibers.     

High lithium ionic conductivity in the garnet‐type oxide Li7−2xLa3Zr2−xMoxO12 (x=0‐0.3) ceramics by sol‐gel method

Lithium garnet‐type oxides Li_7?2xLa₃Zr_2?xMo_xO₁₂ (x=0, 0.1, 0.2, 0.3) ceramics were prepared by a sol‐gel method. The influence of molybdenum on the structure, microstructure and conductivity of Li₇La₃Zr₂O₁₂ were investigated by X‐ray diffraction, scanning electron microscopy, and impedance spectroscopy. The cubic phase Li₇La₃Zr₂O₁₂ has been stabilized by partial substitution of Mo for Zr at low temperature. The introduction of Mo (x≥0.1) can accelerate densification. Li_6.6La₃Zr_1.8Mo_0.2O₁₂ sintered at lower temperature 1100°C for 3 hours exhibits highest total ionic conductivity of 5.09 × 10^?4 S/cm. Results indicate that the Mo doping LLZO synthesized by sol‐gel method effectively lowers its sintering temperature and improves the ionic conductivity.     

Progression from Polyimide to Polyimide Composite in Proton-Exchange Membrane Fuel Cell: A Review

This review is designed as a comprehensive source of research on polyimide and polyimide composite-based fuel cell membranes. Polyimide and modified polyimide-based nanocomposite fuel cell membranes have gained research attention due to high operation temperature of ～150°C. To increase the lifetime of polyimide-based fuel cell, water stability and dimensional stability of hydrated membrane have been studied. Nanofillers such as silica, titania, graphene, carbon nanotube, and polyhedral oligomeric silsesquioxane have been reinforced in polyimide to improve proton conductivity (at low humidity/high temperature) and water stability. Design of new polyimide composite membranes must be focused in future for high water, chemical, and mechanical stability.     

C100高强度大流动性混凝土的试验研究

分析了高强度大流动性混凝土的技术特点 ,研究了内掺硅粉量 ( % )及水泥品种对混凝土强度和流动性的影响 ;根据试验数据总结出混凝土 2 8d的强度规律 ;采用 42 5硅酸盐水泥或普通硅酸盐水泥、内掺硅粉量 10 %～ 15 %、中砂或粗砂、5～ 2 5mm碎石、掺加适量的NF -2 -6缓凝高效减水剂 ,水胶比不大于 0 2 9,能配制出C10 0高强度大流动性混凝土。     

固体废弃物在蒸压加气混凝土中的利用与研究进展

大宗工业固体废物的量在逐年增加,占用环境资源,由于处理不当给社会生产带来了严重的环境问题。相关研究表明,大部分固体废物的成分中含有大量的SiO2和Al2O3等有效成分,可作为硅质材料投入蒸压加气混凝土生产使用。综述搜集了各种固体废物在蒸压加气混凝土中的应用研究,并对各种固体废物进行分类,分析固体废物应用于蒸压加气混凝土生产的可行性,并提出了当下存在的问题以及未来的方向。     

无机硅质仿大理石板材的研制

无机硅质仿大理石板材是以硅酸盐水泥为主要原料,辅以优质石英砂和无机添加剂MFG而制成的一种纯无机的釉面石材,其生产过程免压、免烧、免磨、免抛光,以此方法生产的仿大理石板材在国内尚属首创.本文介绍此项专利技术(专利号CN1072667A).     

The effect of cement alkali content on ASR susceptibility of mortars incorporating admixtures

In this study, the effects of three types of plasticizing chemical admixtures (modified lignosulfonate, sulfonated naphthalene formaldehyde and polycarboxylate based) on deleterious expansion due to alkali–silica reaction (ASR) have been investigated. Two different types of cements with low (0.53 Na₂O eq.) and high (0.98 Na₂O eq.) alkali contents, a non-reactive crushed limestone as fine aggregate and a reactive river sand were used within the scope of the experimental program. ASR tests were conducted according to accelerated mortar bar method (ASTM C 1260). Additionally the flow value, dry unit weight, capillary water absorption and compressive strength tests were performed. Test results indicated that mortars prepared with inert fine aggregate caused no significant expansion, regardless of cement type, admixture type and dosage. However, for mixes containing reactive sand, admixtures increased or decreased the expansion values (compared to plain mortars) depending on the alkali content of cement used. The magnitude of change of expansion also depended on the type and amount of admixture incorporation which have a dominant effect on stability and compactability of mortars. The high-alkali cement usually revealed the ASR expansion augmentation behaviour of admixtures. In contrast, low alkali cement decreased the expansion values compared to the control specimens.     

导热硅胶形状对液冷式电池组热性能影响研究

随着电动汽车能量密度的增加以及充放电功率水平的提高,动力电池热问题日益突出,电池热管理系统设计显得尤为重要。从动力电池组应用场景出发,建立了液冷式电池组有限元模型并仿真分析了4种导热硅胶形状对电池组热性能的影响。研究发现,随着导热硅胶与电池组接触面积的减少,电池组温度有所上升,但温差较小。相比于常规设计方案,改短设计方案在电池组温度略微上升的条件下温度均匀性改善明显,可以为电池热管理系统设计提供参考。     

呼延水厂低温低浊水的絮凝试验研究

针对太原市呼延水厂出水浊度不达标的问题进行了絮凝试验研究.结果表明:该厂原水属低温低浊水,有机胶体较多,絮凝效果差,其根本原因是絮凝剂投量不足.进一步的试验表明:以聚合氯化铝(PAC)为絮凝剂、以活化硅酸为助凝剂,除浊效果较好;活化硅酸的投加时间对絮凝效果有较大的影响,以快速混合用时1min、聚合氯化铝投量为15 mg/L、延迟30 s后投加0.5～1mg/L的活化硅酸(以SiO2,计)为最佳运行条件;滤池反冲洗排水回流至配水井有利于低温低浊水的处理,并可节省絮凝剂或助凝剂的投量.