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The development of aerospace and automotive industries requests lightweight, high-paformance materials, and polymer nanocomposites are ideal candidates in this case, which is shown by the increasingly more publications in this research field over the past two decades. However, the performance of nanocompositenot only depend on the properties of their individual constituents, but on their morphology and surface characteristics of fillers as well. Selections of nanofille~ geometries, e.g. particulate, fibrous or layered have a tremendous influence on the properties of nanocomposites and their processing methods. In this paper, we review the chronological works performed in the field of polymer nanocomposites, in particular epoxy nanocomposites reinforced with layered fillers, such as clay and gitiphene. Surprisingly layered fillers are commercially available and more costeffective than nanoparticles and carbon nanofibres, and these make them to the most extensively studied fillers that can be geared toward future applications, particularly in large-scale polymer nanocomposite production.

Biofuels based on vegetable oils offer the advantages of being sustainable, annually renewable sources of automobile fuel. Despite many years of improvement, use of vegetable-oil-based fuels still has issues, such as oxidation, the stoichiometric point, bio-fuel composition, antioxidants on degradation and the volume of oxygen compared to diesel. Thus, improvements in the emissions from diesel engines fueled by a blend of crude jatropha oil with diesel could be the requirement to meet the reduced emissions regulations in the future. The purpose of this study is to investigate the effects on the vehicle's performance and exhaust emissions of the combustion process of blended crude jatropha oil and palm oil with different ratios. The engine speed was varied from 1500~3000 rpm, the load test condition was varied from 0~100% using a Dynapack chassis dynamometer and crude jatropha oil with a diesel blending ratio from 5~15vol% (CJO5~CJO15) was used. A decrease in HC emissions was found in the combustion process as the ratio of the blend of crude jatropha oil with diesel was increased and also with nearly equal engine performance. The increase in the jatropha oil biodiesel blending ratio promoted the reduction of HC, CO and CO 2 emissions in the range 10vol% to 15vol% of the blends. The improvement in the combustion process with the higher blending ratio is expected to be strongly influenced by the oxygen contained in the blended crude jatropha oil.

The reduction of world oil reserves fossil fuels and increasing environmental concerns significantly influences the popularity of biodiesel as an alternative diesel. This research investigates the effects of storage duration of variant blending waste cooking oil ratio under different storage temperature on fuel properties. The biodiesel samples were stored at different temperatures and were monitored at regular interval over a period of 70 days. Blending of biodiesel was varied from 5vol % (WCO5) ~15vol% (WCO15) and storage temperature from 24°C~35°C. These samples were monitored on a weekly and the effects of storage conditions on properties of biodiesel such as density, kinematics viscosity, acid value, water content and flash point of biodiesel were discussed in detail. The observation of biodiesel shows that the increasing of storage duration of biodiesel derived from waste cocking oil influences to the increasing of density, kinematics viscosity, acid value and water content.

Abstract. Diesel engines generate undesirable exhaust emissions during combustion process and identified as major source pollution in the worldwide ecosystem. To reduce emissions, the improvements throughout the premixing of fuel and air have been considered especially at early stage of ignition process. Purpose of this study is to clarify the effects of swirl velocity on flow fuelair premixing mechanism and burning process in diesel combustion that strongly affects the exhaust emissions. The effects of physical factors on mixture formation and combustion process to improve exhaust emissions are discussed in detail. This study investigated diesel combustion fundamentally using a rapid compression machine (RCM) together with the schlieren photography and direct photography methods. RCM was used to simulate actual phenomenon inside the combustion chamber with changing design parameter such as swirl velocity, injection strategies and variable nozzle concept. The detail behavior of mixture formation during ignition delay period was investigated using the schlieren photography system with a high speed digital video camera. This method can capture spray evaporation, spray interference and mixture formation clearly with real images. Ignition process and flame development were investigated by direct photography method using a light sensitive high-speed color digital video camera. Moreover, the mechanism and behavior of mixture formation were analyzed by newly developed image analysis technique. Under high swirl condition, the ignition delay is extended, the higher heat losses and unutilized highdensity oxygen associated with slower initial heat recovery begins might be the explanation for the longer combustion duration, reductions of pick heat release and promote combustion and soot oxidation. The real images of mixture formation and flame development reveal that the spray tip penetration is bended by the high swirl motion, fuel is mainly distributed at the center of combustion chamber, resulting that flame is only formed at the center region of the combustion chamber. It is necessary for high swirl condition to improve fuel-air premixing.

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Biodiesel is typically made by chemically reacting lipids of palm, vegetable, and waste cooking oils and animal fat with an alcohol producing fatty acid esters. Biodiesel is not efficient in cold weather and this is biodiesel's major problem. Viscosity has influences on the fuel flow rate and leads to poor fuel atomisation during the combustion process. The aim of this study is to determine the effects of biodiesel temperature in the range fom 40 °C and 60 °C on engine performance such as torque, brake power, brake mean effective pressure, and fuel consumption. Three types of biodiesel oil were used (crude palm oil (CPO), waste cooking oil (WCO), and jatropha oil) under biodiesel blending ratio of 5vol%. A single cylinder four-stroke engine was used and operated under different load conditions of 0% and 50% and observed emission of CO, CO2, NOx, and HC. The engine operated at 0% and 50% dynamometer load conditions and running speeds of the engine of 800 rpm, 1200 rpm, 1600 rpm, and 2000 rpm. The results of this study showed that the heating temperatures in the range from 40 °C and 60 o C in CPO10 produced the highest brake power as well as torque and BMEP. For the experimental results of exhaust emission, the preheated temperature affected the degradation of the exhaust emission. In addition, preheated biodiesel increased the pressure on the cylinder combustion chamber. It can be concluded that the biodiesel preheated blend influences the performance and emission. For CPO biodiesel, the preheated biodiesel decreased CO and NOx while the standard diesel produced the lower emission of CO2 and HC. WCO biodiesel blend produced a lower emission with increasing fuel temperature.

The interface between the matrix phase and dispersed phase of a composite plays a critical role in influencing its properties. However, the intricate mechanisms of interface are not fully understood, and polymer nanocomposites are no exception. This study compares the fabrication, morphology, and mechanical and thermal properties of epoxy nanocomposites tuned by clay layers (denoted as m-clay) and graphene platelets (denoted as m-GP). It was found that a chemical modification, layer expansion and dispersion of filler within the epoxy matrix resulted in an improved interface between the filler material and epoxy matrix. This was confirmed by Fourier transform infrared spectroscopy and transmission electron microscope. The enhanced interface led to improved mechanical properties (i.e. stiffness modulus, fracture toughness) and higher glass transition temperatures (T g) compared with neat epoxy. At 4 wt% m-GP, the critical strain energy release rate G 1c of neat epoxy improved by 240 % from 179.1 to 608.6 J/m 2 and T g increased from 93.7 to 106.4°C. In contrast to m-clay, which at 4 wt%, only improved the G 1c by 45 % and T g by 7.1 %. The higher level of improvement offered by m-GP is attributed to the strong interaction of graphene sheets with epoxy because the covalent bonds between the carbon atoms of graphene sheets are much stronger than silicon-based clay.