International Journal of

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A novel geometry for enhancing the sensitivity of intensity modulated refractometric fiber optic sensor for detection of adulteration level in diesel by kerosene is proposed. In this multimode plastic optical fiber is uncladded for specific length and bent into S shape. This geometry is simulated and analyzed using Beam Propagation Method in Beam prop RSOFT software. When sensor is immersed in the diesel then diesel acts as a cladding for uncladded S shape portion of optical fiber. As diesel is adulterated by different volumes of kerosene, refractive index of cladding changes which in turn affects the output intensity of the sensor. The investigation revealed that when such structure of sensor is used to detect the adulteration level in diesel then sensitivity gets improved 4 times for two fold increase in bend curvature of fiber. Thus it is highly sensitive mechanism to determine on line adulteration of diesel and also can be used for other applications.

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Detection of fuel adulteration in real time is the most important need of the world as it generates the hazardous effects on the environment, living and nonliving things. Various automotive users and fuel providers may mix kerosene in petrol and diesel. Adulterated fuel increases air pollution, as well as reduces the performance of vehicle engines. Such a malpractice in fuel is prevailing because vehicles do not have real time adulteration monitoring system. In this study, we propose evanescent wave optical fiber sensor, which is interfaced with peripheral interface controller (PIC) to detect fuel adulteration percentage by means of change in refractive index. A fuel sensor prototype is formulated and tested to detect adulteration percentage in petrol and diesel by kerosene. The sensor is useful as it has simple construction, real time operation, and safety handling with inflammable fuel for in-situ measurements. The sensors have detectable capacity of 5% contaminant in petrol and diesel using evanescent wave absorption technique. Other traditional techniques are able to detect presence of about more than 10 % of fuel adulteration only in the laboratory. PIC is used with a fuel sensor for incorporating an automation and sophistication in automotive display, so that it is more useful to layman.

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Owing amongst other to its high electron mobility, fullerene C70, has been widely used as an electron transporting layer in organic solar cells. In this research, we report the use of C70 thin films as electron transport layers of planar perovskite solar cells (PSCs) using a conventional device structure. The thickness of the C70 layer has been optimized to achieve the best efficiency of 12%. It is demonstrated that ultra-thin C70 films can effectively block holes and thus become selective to the transport of electrons in PSC devices.