The addition of ethanol to diesel fuel simultaneously decreases cetane number, high heating value, aromatics fractions and kinematic viscosity of ethanol blended diesel fuels and changes distillation temperatures. An additive used to keep the blends homogenous and stable, and an ignition improver, which can enhance cetane number of the blends, have favorable effects on the physicochemical properties related to ignition and combustion of the blends with 10% and 30% ethanol by volume.The emission characteristics of five fuels were conducted on a diesel engine. At high loads, the blends reduce smoke significantly with a small penalty on CO, acetaldehyde and unburned ethanol emissions compared to diesel fuel. NO x and CO 2 emissions of the blends are decreased somewhat. At low loads, the blends have slight effects on smoke reduction due to overall leaner mixture. With the aid of additive and ignition improver, CO, unburned ethanol and acetaldehyde emissions of the blends can be decreased moderately, even total hydrocarbon emissions are less than those of diesel fuel. The results indicate the potential of diesel reformation for clean combustion in diesel engines. r

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Due to a huge number of M2M devices expected to access the network simultaneously, congestion and overload of networks are the core challenges to the 5G ultra‐dense M2M networks design. In this paper, an optimal traffic‐load control scheme is proposed to overcome the challenges. Since the base station lacks accurate information about the traffic‐load of network resulting in an unachievable solution to the optimal control scheme in practice, we propose two different traffic‐load estimation schemes corresponding to the two different access protocols. For the first protocol that the collision devices are not barred by an access probability, we propose a markov‐chain based estimation scheme according to the collision state of network. For the second protocol that the collision devices are barred by an access probability, we estimate the traffic‐load using the number of success devices and the average number of new active devices in each slot. Both estimation schemes ensure that the practical control schemes are very close to the theoretical optimal control scheme. In addition, we prove that the optimal performances of the two protocols are exactly the same in theory. Finally, the simulation results exhibit our conclusion and show the superior performances of our proposed scheme.