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Foamed bitumen mixes are produced by mixing foamed bitumen with aggregate at ambient conditions. However, the variations in the temperature of mineral aggregate at the time of mixing have a profound influence on the properties of the foamed bitumen mixes produced. A feasibility study previously undertaken to investigate the possible benefits of heating the aggregate moderately (above ambient temperature but below 100°C) before foam treatment, highlighted the improvement of mix properties that is achievable. The properties that can be enhanced include particle coating; mix cohesion and tensile strength, as well as a degree of compaction when compared with the equivalent properties of conventional cold foam mixes (CMA). This has been found to be applicable to, in particular, reclaimed asphalt pavement (RAP) and densely graded crushed aggregates. The feasibility study was undertaken exclusively at laboratory scale. A second phase, more focussed research project was subsequently launched in the Netherlands using the mixes that show the most potential to benefit most from the "Half-warm Foamed Bitumen Treatment" process viz, STAB (crushed stone ashalt concrete used in the Netherlands as a base course layer) and RAP combinations. This investigation was undertaken at laboratory level as well as full scale production trials. This paper discusses the findings of the entire investigation into half-warm foamed (HWF) bitumen treatment, carried out in South Africa and the Netherlands. As special development, the reuse of porous asphalt (PA) RAP in HWF PA, is also discussed. With up to 40% less energy consumption than that required for manufacture than hot mix asphalt (HMA), HWF asphalt mixes can provide comparative monotonic properties at higher test temperatures, similar fatigue properties and a lower phase angle at low loading frequencies. The improvement of mix properties relative to CMA is significant. This indicates that the HWF process holds the potential for successful implementation in pavement layers. [ABSTRACT FROM AUTHOR]

Vanadium dioxide displays thermochromic properties based on its structural phase transition from monoclinic VO 2 (M) to rutile VO 2 (R) and vice versa , and the accompanying reversible metal-insulator transition. We developed a single layer coating comprising VO 2 (M) and SiO 2. We applied the coating from an alcoholic solution comprising vanadium(IV) oxalate complex and pre-oligomerized tetra ethoxy silane to SiO 2 -coated float glass using dip coating, and thermally annealed the dried xerocoat in a two-step process. The addition of SiO 2 as coating matrix resulted in non-scattering coatings with low surface roughness and random distribution of VO 2 nanodomains (≤200 nm). Furthermore, the formation of the coating, comprising a phase separation yielding SiO 2 and VO 2 nanodomains during the thermal anneal, was studied in detail. The coating displays unrivalled optical properties, combining high visible light transmission T vis > 60% and large solar modulation Δ T sol ≥ 10%. When applied in insulating glass units, the coating has a positive impact on energy savings for heating and cooling of buildings in intermediate climates, which we demonstrated through building energy simulations. For a typical house in the Netherlands, energy savings up to 24% were obtained. In addition, we demonstrate a coating stability comparable to current energy-efficient window coatings during processing into and in insulating glass units through (accelerated) life time tests. • Solution processed, single layer thermochromic coating with unrivalled optical properties (T vis > 60% and Δ T sol ≥ 10%). • Phase separation during thermal anneal resulted in a thermochromic coating comprising nanodomains of VO 2 (M) and SiO 2. • SiO 2 matrix led to non-scattering coatings with low surface roughness and random distribution of VO 2 nanodomains (≤200 nm). • In IGUs, the coating has a positive impact on energy savings (up to 24%), as demonstrated by building energy simulations. • The coating is robust and displays a stability comparable to current energy-efficient window coatings based on (A)LT. [ABSTRACT FROM AUTHOR]

Purpose: Improvement of biomechanical properties of cobalt-chromium-molybdenum (CoCrMo) implant surface and reduction of adhesive wear is achieved by titanium-nitride (TiN) coating in vitro. Less pain, higher postoperative outcome scores and a lower revision rate after TKA with a TiN-coated CoCrMo TKA compared with uncoated CoCrMo TKA after 10-year follow-up was hypothesized., Methods: In a double-blinded RCT, 101 patients received a cementless mobile-bearing CoCrMo TKA, either TiN-coated or uncoated. The primary outcome measure was the visual analogue scale (VAS) score for pain and secondary outcome measures were the Knee Society Score (KSS), Oxford Knee Score (OKS), revision rate and adverse events. Patients were assessed at 6 weeks, 6 months, 1 year, 5 years and 10 years, postoperatively., Results: 68 patients (67%) were available for 10-year follow-up. No difference was found in any of the assessed outcome measures with a mean decrease in VAS score (31.6 ± 22.9) and a mean increase in OKS (10.9 ± 8.4), KSS (29.3 ± 31.4), KSSK (26.4 ± 18.2) and KSSF (4.1 ± 22.9). Overall revision rate was 7% (coated 6% vs uncoated 8%) without additional revision procedures between 5 and 10-year follow-up., Conclusions: The in vitro potential benefits of TiN coating did not result in better clinical outcome when compared to an uncoated cementless TKA. Pain, functional outcome and revision rates were comparable after 10-year follow-up. TiN-coated cementless TKA provides comparable good long-term results, similar to uncoated cementless CoCrMo TKA., Level of Evidence: Level 1, Therapeutic Study NETHERLANDS TRIAL REGISTER: NL2887/NTR3033.