Hadi Manap

Ammonia detection in the UV region using an optical fiber sensor

This paper describes an optical fiber sensor for the monitoring of ammonia gas. An open path optical technique is used to analyze the absorption lines of ammonia within the ultra violet region. Experimental results describing the operation of the sensor are presented and are compared with theory. A comparison between a commercial sensor has been carried out and cross sensitivity testing with regard to oxygen and carbon dioxide gas is reported.

Real-time monitoring of agricultural ammonia emissions based on optical fibre sensing technology

An optical fibre sensor system, capable of monitoring ammonia gas in real-time is described and its suitability for monitoring ambient levels, as low as 1ppm, within confined areas, e.g. livestock sheds, is presented. Unlike other optical sensors, which monitor in the infra-red region, this optical fibre sensor is based on monitoring absorption due to ammonia in the ultraviolet region. By monitoring in the UV region it is possible to overcome many of the cross-sensitivity issues previously associated with ammonia sensing, such as cross-sensitivity with atmospheric gases carbon dioxide and oxygen and also humidity. The sensor exhibits a fast response time (1s) to a wide range of ammonia gas concentrations (1 –50ppm).

Enhancement of Heat Transfer Coefficient in an Automobile Radiator Using Multi Walled Carbon Nano Tubes (MWCNTS)

Enhancement of heat transfer coefficient continues to be an important research area in various fields of engineering ranging from microelectronics to high powered automobiles. The initial effort in the present research study is to enhance the heat transfer coefficient in a vehicle radiator using nanofluids with high thermal conductivity. The world’s most abundant element ‘Carbon’ astoundingly exists in various structures and one such form is tube commonly known as Carbon Nanotubes (CNTs). Heat transfer enhancement in water and coolant based systems with different concentrations of nano particles (carbon nanotubes) have been investigated from an engineering system perspective. One such system considered is a “SUZUKI (800CC) - CAR RADIATOR”, cooling circuit using different nanofluids to replace the conventional engine coolant. In the present study, the effect of nano-fluid heat transfer to enhance in water and coolant based systems with multi walled carbon nanotubes has been investigated. The improvement of heat transfer when compared to water, coolant (water + ethylene glycol 60:40) and water with MWCNTS and coolant with MWCNTS has been studied.It has been observed that there is an enhancement of heat transfer up to 30% when coolant and CNTS are used as a cooling medium.Copyright

Cross Sensitivity Study for Ammonia Detection in Ultra Violet Region Using an Optical Fibre Sensor

This paper describes an optical fibre sensor for the monitoring of ammonia gas. An open path optical technique is used to analyze the absorption lines of ammonia within the ultra violet region. A cross sensitivity study mainly regarding water vapor and the advantage of using ultra violet light have been discussed. Experimental results describing the operation of the sensor are presented and are compared with theory. The optical sensor for ammonia shows very promising results and are very close to the theoretical spectrum.

A preliminary study of green-house gases interference for ammonia sensing in the mid UV region

This paper describes a preliminary study of the possibility for greenhouse interference during ammonia measurement in the 200 nm – 230 nm region. An absorption spectrum for ammonia was compared with the greenhouse gases absorption lines to theoretically justify that there were no discernible interference effects during the ammonia concentration measurements. It was theoretically found that the primary greenhouse gases namely ozone, methane and nitrous oxide have no significant interference for ammonia sensing in the 200 nm – 210 nm region.

In-situ monitoring of ammonia gas using an optical fibre based approach

An optical fibre sensor for the monitoring of low level atmospheric ammonia concentrations is presented. The measuring technique employed is based on a differential optical absorption approach, rather than a semiconductor based technique which is generally exploited within comparable commercially available products. The sensor described herein demonstrates vast improvements in terms of sensitivity, selectivity and lifespan over ammonia sensors currently available commercially. Extensive laboratory-based experimental tests demonstrate the sensors ability to monitor concentrations as low as 1ppm without any notable cross-sensitivity issues to atmospheric gases such as nitrogen, oxygen and carbon dioxide. Furthermore, in-situ experimental tests within an agricultural cattle enclosure demonstrate sensors suitability to environments where low concentration monitoring of ammonia over extended periods of time is necessary.

Nano-Dimensional Properties of Si-FinFET Transistor Based on I ON /I OFF Ratio and Subthreshold Swing (SS)

This paper presents design the optimal channel dimensions for Silicon Fin Feld Effect Transistor (Si-FinFET) for improvement electrical characteristic of Si-FinFET depending on the electrical characteristics of the channel (I ON /I OFF , SS, VT, DIBL). The MuGFET simulation tool has been using to investigate the electrical characteristics of Si-FinFET. The current voltage characteristics has been simulating with different dimensions channel (length, width and oxide thickness). The best channel dimensions of Si-FinFET observed based on electrical characteristics at the working voltage VDD range of 0-5 V. Note that the results with the scaling channel dimensions. Depending on I ON /I OFF ratio higher value, and nearest SS to the ideal SS, the best scaling channel dimensions (K) will be K=0.25 at VDD=5 V and K=0.25 at VDD=0.5 V.

Diameter optimization of Nano-scale SiNWT based SRAM cell

This paper represents diameter and logic voltage level optimizations of 6-Silicon Nanowire Transistors (SiNWT) SRAM. This study is to demonstrate diameter of nanowires effects at a different logic voltage level (Vdd) on the static characteristics of Nano-scale SiNWT Based SRAM Cell. Noise margins (NM) and inflection voltage (Vinf) of transfer characteristics are used as limiting factors in this optimization. Results indicate that optimization depends on both diameters of nanowires and logic voltage level (Vdd). And increasing of logic voltage level from 1V to 3V tends to decrease in optimized nanowires diameters but with increasing in current and power dissipation. SRAM using nanowires transistors must use logic level (2V or 2.5V) to produce SRAM with lower diameters and suitable inflection currents and then with lower power dissipation as possible.

The Interference Study of Green-House Gases for an Ammonia Sensor

This paper describes a preliminary study of the possibility for greenhouse interference during ammonia measurement in the 200nm-230 nm region. An absorption spectrum for ammonia was compared with the greenhouse gases absorption lines to theoretically justify that there were no discernible interference effects during the ammonia concentration measurements. It was theoretically found that the primary greenhouse gases namely ozone, methane and nitrous oxide have no significant interference for ammonia sensing in the 200nm-210 nmregion.

In-situ low concentration monitoring of ammonia using an optical fibre sensor

An optical fibre sensor has been developed for the monitoring of low level atmospheric ammonia. In-situ experimental tests within an agricultural cattle enclosure in the Republic of Ireland demonstrate the effectiveness of the developed sensor to accurately monitor concentration levels of between 0 and 2 ppm. Finally, a comparison with a commercially available sensor demonstrates the suitability of the developed sensor in terms of sensitivity and selectivity.