The analyses conducted in this research were based on three methodologies for the field measurement of saturation headways. The first method (M1), the one on which most past studies were based, measured the characteristics of Vehicles 4 to 12 in a standing queue. M2, the method found in the Highway Capacity Manual (HCM), counted all vehicles in a standing queue, regardless of queue length. M3 included arrivals that joined the standing queue as long as vehicles were up to 140 ft from the stop line. This study focused on one approach of a high-design intersection with heavy, random arrivals. The large number of observations and the practically ideal traffic conditions enabled the acquisition of several statistically significant results on saturation flow (s), start-up lost time (SULT), and start-up response time (SRT): (a) when long queues are present, the typical field measurement of s based on the first 12 vehicles is an overestimate of s for through vehicles and an underestimate of s for protected left-turning vehicles; (b) the type of movement had a more dominant role in determining s than the level of saturation (or queue length); (c) SRT displayed a bigger variation than headwaysthe left-turning movement had a significantly shorter SRT than the through movement did; and (d) much higher SULTs were estimated in this study compared with those in the HCM.Saturation headways are typically estimated from field measurements of the elapsed time between the 4th and 10th to 12th vehicles in a queue (1). The results of these measurements have been used widely under two questionable assumptions:

At present, PANI/MWNT composites have been paid more attention as promising electrode materials in supercapacitors. Yet some shortcomings still limit the widely application of PANI/MWNT electrolytes. In this work, in order to improve capacitance ability and long-term stability of electrode, a multi-amino dendrimer (PAMAM) had been covalently linked onto multi-walled carbon nanotubes (MWNT) as a bridge to facilitating covalent graft of polyaniline (PANI), affording P-MWNT/PANI electrode composites for supercapacitor. Surprisingly, ordered arrays of PANI nanowires on MWNT (setaria-like morphology) had been observed by scanning electron microscopy (SEM). Electrochemical properties of P-MWNT/PANI electrode had been characterized by cyclic voltammetry (CV) and galvanostatic charge-discharge technique. The specific capacitance and long cycle life of P-MWNT-PANI electrode material were both much higher than MWNT/PANI. These interesting results indicate that multi-amino dendrimer, PAMAM, covalently linked on MWNT provides more reaction sites for in-situ polymerization of ordered PANI, which could efficiently shorten the ion diffusion length in electrolytes and lead to making fully use of conducting materials.

PMMA bone cement has been clinically used for decades in vertebroplasty due to its high mechanical strength and satisfactory injectability. However, the interface between bone and PMMA is fragile and more prone to refracture in situ because PMMA lacks a proper biological response from the host bone with minimal bone integration and dense fibrous tissue formation. Here, we modified PMMA by incoporating borosilicate glass (BSG) with a dual glass network of [BO 3 ] and [SiO 4 ], which spontaneously modulates immunity and osteogenesis. In particular, the BSG modified PMMA bone cement (abbreviated as BSG/PMMA cement) provided an alkaline microenvironment that spontaneously balanced the activities between osteoclasts and osteoblasts. Furthermore, the trace elements released from the BSGs enhanced the osteogenesis to strengthen the interface between the host bone and the implant. This study shows the first clinical case after implantation of BSG/PMMA for three months using the dual-energy CT, which found apatite nucleation around PMMA instead of fibrous tissues, indicating the biological interface was formed. Therefore, BSG/PMMA is promising as a biomaterial in vertebroplasty, overcoming the drawback of PMMA by improving the biological response from the host bone.

Poly (phenol-formaldehyde resin) (PF)/carbon fiber (PF/CF) composites with different ratios of graphene-Fe 3 O 4 were manufactured through molding-press process. Ferroferric oxide was introduced into graphene to avoid its reunion. The effects of graphene-Fe 3 O 4 the morphology, thermal conductivity, friction performance and thermal properties of composites were investigated via SEM, thermal constant analyzer, tribological and TGA tests. Scanning electron microscopy scanning proved the enhanced friction surface of the composites and the combination of the resin with the fiber. Thermal conductivity measurements showed that the best result was achieved with 2.0 wt% graphene-Fe 3 O 4. The friction coefficient and wear rate also decreased drastically with the addition of graphene-Fe 3 O 4 based on the tribological results.