Effects of risky bus driving behaviors on motorcyclists' and car drivers' traffic safety perceptions in mixed traffic flow.

OBJECTIVE: This study investigates traffic safety perceptions of motorcyclists and car drivers toward risky bus driving behaviors (RBDBs) in mixed traffic flow (MTF). METHODS: The study identified 10 RBDBs and employed images in a unique questionnaire survey. Further, permutation tests were employed to compare perceptions of motorcyclists in scenarios involving bus-motorcycle-car flow and bus-motorcycle flow and to compare their perceptions to those of car drivers'. Moreover, heteroskedastic generalized ordered logit regression models were utilized to predict traffic safety perceptions of motorcyclists and car drivers toward RBDBs. RESULTS: High-speed bus driving is perceived as the most dangerous situation, while continuous flashing of lights at vehicles in front is perceived as the least dangerous. The permutation test revealed that motorcyclists tend to perceive RBDBs as less dangerous in bus-motorcycle flow than in mixed flow with cars, while car drivers consider them safer than motorcyclists. The regression model revealed that among the RBDBs, bus moving at high speeds, abruptly overtaking, abruptly changing lanes, and suddenly pulling over at bus stops are perceived as the most dangerous by motorcyclists and car drivers. The study also discusses the relationships between the socio-demographic characteristics of motorcyclists/car drivers and their safety perception toward RBDBs. CONCLUSIONS: These findings could inform the development of interventions to reduce RBDBs and improve traffic safety for motorcyclists and car drivers.

Facile preparation of porphyrin@g-C3N4/Ag nanocomposite for improved photocatalytic degradation of organic dyes in aqueous solution.

In the quest of improving the photocatalytic efficiency of photocatalysts, the combination of two and more semiconductors recently has garnered significant attention among scientists in the field. The doping of conductive metals is also an effective pathway to improve photocatalytic performance by avoiding electron/hole pair recombination and enhancing photon energy absorption. This work presented a design and fabrication of porphyrin@g-C3N4/Ag nanocomposite using acid-base neutralization-induced self-assembly approach from monomeric porphyrin and g-C3N4/Ag material. g-C3N4/Ag material was synthesized by a green reductant of Cleistocalyx operculatus leaf extract. Electron scanning microscopy (SEM), X-ray diffraction (XRD), FT-IR spectroscopy, and UV-vis spectrometer were utilized to analyse the properties of the prepared materials. The prepared porphyrin@g-C3N4/Ag nanocomposite showed well integration of porphyrin nanostructures on the g-C3N4/Ag's surface, in which porphyrin nanofiber was of the diameter in nanoscales and the length of several micrometers, and Ag NPs had an average particle size of less than 20 nm. The photocatalytic behavior of the resultant nanocomposite was tested for the degradation of Rhodamine B dye, which exhibited a remarkable RhB photodegrading percentage. The possible mechanism for photocatalysis of the porphyrin@g-C3N4/Ag nanocomposite toward Rhodamine B dye was also proposed and discussed.