Haze in China has been increasing in frequency of occurrence as well as the area of the affected region. Here, we report on a new mechanism of haze formation, in which coexistence with NOx can reduce the environmental capacity for SO2, leading to rapid conversion of SO2 to sulfate because NO2 and SO2 have a synergistic effect when they react on the surface of mineral dust. Monitoring data from ...

This paper describes recent research on flapping-wing micro air vehicles, based on insect-like aerodynamics. A combined analytical, experimental and CFD approach is being adopted to understand and design suitable wing aerodynamics and kinematics. The CFD has used the Fluent 6 commercial code together with the grid-generating software Gambit 2; the experiments have been conducted in air and wate...

background: in large cities, the share of vehicles in air pollutants emissions is nearly 70% that is mainly due to use of fossil fuels. environmental simulation has many advantages such as accuracy and speed of modeling. present study was conducted to create a model of air pollution [carbon monoxide (co) and nitrogen oxides (nox)] from vehicles in fifty following years, in mashhad. methods: acc...

In this paper, we present an interesting method to microfabricate a tilted micro air jet generator. We used the well-know deep reactive ion etching (DRIE) technique in order to realize in a silicon substrate a double side etching. For aircraft and cars, micro air jets will take an important place for fluid control. Micro air jets are characterized by their speed, frequency and tilt. Usually, th...

With 2003 Fatality Analysis Reporting System data, we examined relationships among predictors of motor vehicle injury/fatality outcomes for younger (35-54 years) and older (65 years and older) drivers. Using the Precede-Proceed Model of Health Promotion as an organizing framework, we classified variables into person, vehicle and environment domains and conducted a multinomial logistic regressio...

Programs to reduce tra¢ c congestion and air pollution by restricting use of motor vehicles on working days have generally not met with success, given existing studies of such programs. We conduct the …rst study of Quito, Ecuador’s three-year-old Pico y Placa program and …nd that it has reduced ambient concentrations of carbon monoxide (CO), a pollutant primarily emitted by vehicles, by 9-11% d...

Abstract Autonomous vehicles have been envisioned for more than 100 years. One of the first suggestions was a front cover Scientific America back in 1916. Today, it is possible to get cars that drive autonomously extended distances. We are also starting see micro-mobility solutions, such as Nuro pizza delivery. Building autonomous can operate urban environments with diverse set road-users far f...

Abstract Most insects and hummingbirds can generate lift during both upstroke downstroke with a nearly horizontal flapping stroke plane, perform precise hovering flight. Further, most birds utilize tails muscles in wings to actively control the flight performance, while their based on wing root along wing’s passive deformation. Based above principles of insects, Flapping Wing Micro Air Vehicles...

in this study, the effect of the levels of hydrogen addition to methane-air premixed flame in a micro-stepped reactor has been studied numerically. in addition, the effects of mixture velocity and walls’ thermal conductivity (kw) on the flame’s location, temperature, and species distribution in a micro reactor were calculated using a 2d numerical laminar steady code. the results showed that an ...