Wastewater Denitrification Using Methanol as a Hydrogen Donor Separated by a Silicon Rubber Membrane.

The role of more than one binding site on a nitroxide free radical in magnetic resonance determinations of the properties of the complex formed with a hydrogen donor is examined. The expression that relates observed hyperfine couplings in EPR spectra to complex formation constants and concentrations of each species in solution becomes much more complex when multiple binding sites are present, but reduces to a simpler form when binding at the two sites occurs independently and the binding at the non-nitroxide site does not produce significant differences in the hyperfine coupling constant in the complexed radical. Effects on studies of hydrogen bonding between multiple binding site nitroxides and hydrogen donor solvent molecules by other magnetic resonance methods are potentially more extreme.

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Fracture-Tolerant and Shear-Resistant Interlayers for Mitigation of Reflective Cracking

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198119847622 ◽

2019 ◽

Vol 2673 (10) ◽

pp. 35-46

Author(s):

Cristian Cocconcelli ◽

Bongsuk Park ◽

Jian Zou ◽

George Lopp ◽

Reynaldo Roque

Keyword(s):

Asphalt Pavement ◽

Aggregate Size ◽

Cost Effective ◽

Design Guidelines ◽

Reflective Cracking ◽

Rubber Membrane ◽

Near Surface ◽

Field Evidence ◽

Cracking Performance ◽

Interface Cracking

Reflective cracking is frequently reported as the most common distress affecting resurfaced pavements. An asphalt rubber membrane interlayer (ARMI) approach has been traditionally used in Florida to mitigate reflective cracking. However, recent field evidence has raised doubts about the effectiveness of the ARMI when placed near the surface, indicating questionable benefits to reflective cracking and increased instability rutting potential. The main purpose of this research was to develop guidelines for an effective alternative to the ARMI for mitigation of near-surface reflective cracking in overlays on asphalt pavement. Fourteen interlayer mixtures, covering three aggregate types widely used in Florida, and two nominal maximum aggregate sizes (NMAS) were designed according to key characteristics identified for mitigation of reflective cracking, that is, sufficient gradation coarseness and high asphalt content. The dominant aggregate size range—interstitial component (DASR-IC) model was used for the design of all mixture gradations. A composite specimen interface cracking (CSIC) test was employed to evaluate reflective cracking performance of interlayer systems. In addition, asphalt pavement analyzer (APA) tests were performed to determine whether the interlayer mixtures had sufficient rutting resistance. The results indicated that interlayer mixtures designed with lower compaction effort, reduced design air voids, and coarser gradation led to more cost-effective fracture-tolerant and shear-resistant (FTSR) interlayers. Therefore, preliminary design guidelines including minimum effective film thickness and maximum DASR porosity requirements were proposed for 9.5-mm NMAS (35 µm and 50%) and 4.75-mm NMAS FTSR mixtures (20 µm and 60%) to mitigate near-surface reflective cracking.

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Scalable fabrication of carbon materials based silicon rubber for highly stretchable e-textile sensor

Nanotechnology Reviews ◽

10.1515/ntrev-2020-0088 ◽

2020 ◽

Vol 9 (1) ◽

pp. 1183-1191

Author(s):

Xinlin Li ◽

Rixuan Wang ◽

Leilei Wang ◽

Aizhen Li ◽

Xiaowu Tang ◽

...

Keyword(s):

Carbon Nanomaterials ◽

Electrical Performance ◽

Gauge Factor ◽

Multiwalled Carbon ◽

Silicon Rubber ◽

Smart Clothing ◽

Mechanical And Electrical Properties ◽

Highly Stretchable ◽

Textile Sensor ◽

High Level

AbstractDevelopment of stretchable wearable devices requires essential materials with high level of mechanical and electrical properties as well as scalability. Recently, silicone rubber-based elastic polymers with incorporated conductive fillers (metal particles, carbon nanomaterials, etc.) have been shown to the most promising materials for enabling both high electrical performance and stretchability, but the technology to make materials in scalable fabrication is still lacking. Here, we propose a facile method for fabricating a wearable device by directly coating essential electrical material on fabrics. The optimized material is implemented by the noncovalent association of multiwalled carbon nanotube (MWCNT), carbon black (CB), and silicon rubber (SR). The e-textile sensor has the highest gauge factor (GF) up to 34.38 when subjected to 40% strain for 5,000 cycles, without any degradation. In particular, the fabric sensor is fully operational even after being immersed in water for 10 days or stirred at room temperature for 8 hours. Our study provides a general platform for incorporating other stretchable elastic materials, enabling the future development of the smart clothing manufacturing.

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