Electrocatalytic Detection of Dopamine and Uric acid at poly (Basic Blue B) Modified Carbon Nanotube Paste Electrode

Electropolymerization of Basic Blue B by cyclic voltammetry (CV) onto the carbon nanotube (CNT) paste electrode results in the formation ofpoly (Basic Blue B) film/modified CNT paste electrode (PBBB/MCNTPE). The Modified electrode was used for the electrochemical determinationof dopamine (DA) and uric acid. CV results showed that this PBBB/MCNTPE have reversible redox behavior in electrolyte solution. The resultingPBBB/MCNTPE were characterized using field emission scanning electron microscope. The analytical ability was tested with respect to the scan rate,number of cycle, pH of solution, and concentration variation. Measurement of these analytes studied simultaneously by CV and differential pulsevoltammetry methods. The analytical curve for DA presented linear dependence over the concentration range from 3 × 10 M witha linear correlation coefficient of 0.99036. The detection limit of this method was 5.8 × 10. The method has good selectivity and sensitivity withsatisfactory results.Keywords: Carbon nanotubes paste electrode, Cyclic voltammetry, Poly (Basic Blue B), Dopamine, Uric acid

Optical properties of diamond like carbon films prepared by DC-PECVD

Diamond-like carbon (DLC) thin films were deposited at different substrate temperatures using methane and hydrogen gas in DC-PECVD at 2x10-1Torr. From the light transmission using UV-VIS spectroscopy it was found that the optical transition had changed from allowed indirect transition to allowed direct transition as the substrate temperature increased. The Optical gap increased with temperature, highest of 3.034 eV was observed at 573 K, beyond which it dropped. Colour of the film changed from light brownish to a colourless transparent film in the higher temperature. The Urbach energy decreased from 1.25 eV to 0.75 eV with increasing substrate temperature till 573 K and a slight increase after it. This trend is attributed to change in sp3/sp2 ratio or change in structure. The cluster size decreases with temperature, resulting in larger band gap and the structure more ordered. Similar pattern is also witnessed in the emission spectrum of the photoluminescence

Short-Term Ability of Concrete Containing Palm Oil Fuel Ash Exposed to Sodium Sulphate

Uncontrolled palm oil waste disposal can lead to an environmental problem, and recycling the waste can assist in reducing the disposal problem. On another side, concrete exposed to sulphate normally will lose its strength after some time. Replacing cement with palm oil fuel ash (POFA) can lower the disposal issue and help reduce the concrete from strength losses. The main objective of this study is to investigate the short-term effects on the strength of concrete containing POFA exposed to sulphate solution. The POFA was prepared by drying in an oven for 24 hours at 105°C and sieved passing through a 300 μm sieve. Then, the POFA had been refined using ball mills for two hours. The percentage of POFA as cement replacement used in this study is 10%, 20% and 30% by volume of cement. Two types of specimens were prepared, i.e., cube specimen (100 mm × 100 mm × 100 mm) and prism specimen (500 mm × 100 mm × 100 mm) that fully immersed in water and 3.5% sulphate solutions. Density test, water absorption test, compression strength test and flexural strength test were conducted after 7 and 28 days of the exposure period. A total of 144 specimens was subjected to these tests. The experiments show that concrete with 10% replacement of POFA had a higher slump value, while the density test showed that the 10% POFA mixture had a lower density than the other specimens. Furthermore, the water absorption test showed that more POFA in concrete contributes to higher water absorption when exposed to sulphate solution compared to water. In conclusion, the compressive strength and flexural strength test recorded replacement of 10% POFA is the highest strength of concrete containing POFA exposed to sulphate solution and water

Short-Term Ability of Concrete Containing Palm Oil Fuel Ash Exposed to Sodium Sulphate

Uncontrolled palm oil waste disposal can lead to an environmental problem, and recycling the waste can assist in reducing the disposal problem. On another side, concrete exposed to sulphate normally will lose its strength after some time. Replacing cement with palm oil fuel ash (POFA) can lower the disposal issue and help reduce the concrete from strength losses. The main objective of this study is to investigate the short-term effects on the strength of concrete containing POFA exposed to sulphate solution. The POFA was prepared by drying in an oven for 24 hours at 105°C and sieved passing through a 300 μm sieve. Then, the POFA had been refined using ball mills for two hours. The percentage of POFA as cement replacement used in this study is 10%, 20% and 30% by volume of cement. Two types of specimens were prepared, i.e., cube specimen (100 mm × 100 mm × 100 mm) and prism specimen (500 mm × 100 mm × 100 mm) that fully immersed in water and 3.5% sulphate solutions. Density test, water absorption test, compression strength test and flexural strength test were conducted after 7 and 28 days of the exposure period. A total of 144 specimens was subjected to these tests. The experiments show that concrete with 10% replacement of POFA had a higher slump value, while the density test showed that the 10% POFA mixture had a lower density than the other specimens. Furthermore, the water absorption test showed that more POFA in concrete contributes to higher water absorption when exposed to sulphate solution compared to water. In conclusion, the compressive strength and flexural strength test recorded replacement of 10% POFA is the highest strength of concrete containing POFA exposed to sulphate solution and water

Influence of retrogression and re-aging heat treatment to stress corrosion cracking resistance on Al-Zn-Mg-Cu alloy / Deraman R., Aziz M. R. And Y. Yaakob

The Al-Zn-Mg-Cu alloy is classified as a high strength to weight ratio material and is widely used in the aerospace structures. This alloy is susceptible to severe localized corrosion induced by heat treatment. The objective of this study is to elucidate alternative heat treatment techniques, which reduce the alloys susceptibility to Stress Corrosion Cracking (SCC). A series of different heat treatments have been performed in the Al-Zn-Mg-Cu alloy using cube shaped and C-ring specimens that had been T6- and T7-tempered and undergone Retrogression and Re-aging (RRA) heat treatments. The specimens were exposed to hardness testing, optical testing and immersion testing in a corrosive environment. The effectiveness of the heat treatments was evaluated with respect to improvements in corrosion resistance and the longevity of the Al-Zn-Mg-Cu alloy. The susceptibility of the Al-Zn-Mg-Cu alloy to SCC has been directly related to the precipitation of MgZn2 particles at the grain boundaries. Precipitation hardening of Al-Zn-Mg-Cu alloy increases the hardness of the material, but increases susceptibility to SCC failure. RRA treatment greatly improved the corrosion resistance and longevity of the alloy combined with minimal strength reduction

A secure data authentication in wireless body area network for health monitoring using electrocardiogram-based key agreement

Wireless Body Area Network (WBAN) comprises of a set of biomedical sensors, which are implanted into or placed around a human body to serve a variety of network applications constantly. One of the applications, the ubiquitous health monitoring, has improved the ability of healthcare providers to deliver appropriate treatments to the patients either in hospitals or at homes. As the need of this application increases, several security issues also arise due to the nature of open wireless medium. Moreover, implementing an effective security mechanism uses a significant part of the available energy in a WBAN, whereby the sensors have limited resource constraints in terms of power consumption and memory space. Thus, this paper presents a new authentication protocol model that utilizes Electrocardiogram (ECG) signal as biometric as well as cryptographic key to ensure that the transmitted data are originated from the required WBAN. Due to the uniqueness and the permanence property of ECG signal, the proposed model is developed to achieve optimal security performance and required lightweight manners of to the resource-limited biomedical sensors. The simulation system is implemented based on the process of an improved fuzzy vault scheme with a new error correction algorithm, which results in reducing computational complexity, communication load and storage overhead when compared to several previous work

Analysis of rectangular flexible horizontal piezoelectric cantilever beam base on ANSYS

This paper presents the analysis of energy harvester by using rectangular flexible piezoelectric cantilever beam in which applied on sea wave. The limitation of blade design is it only focus on single direction flow of sea wave motion. The finite element model is constructed by using ANSYS to optimize the blade design to maximize the output power. The analysis of rectangular flexible piezoelectric design shows the ability to generate variable of electric power from minimum 20 µW up to 141.30 µW, with dimension of width, length, height of piezo is 10 mm, 30 mm, 0.10 mm and amplitude of sea wave surface of 1.5 m respectively

Model kesediaan pelaksanaan sistem kawalan industri di persekitaran awan dari perspektif keselamatan maklumat

Persekitaran awan adalah satu bidang yang pesat berkembang dengan keupayaan mengakses perkhidmatan dari mana sahaja dan pada bila-bila masa. Sistem Kawalan Industri atau ICS adalah istilah umum untuk sistem kawalan yang digunakan di dalam infrastruktur kritikal. Apabila ICS dilaksanakan di persekitaran awan, keselamatan maklumat menjadi satu kebimbangan utama bagi organisasi ICS. Sebelum melaksanakan ICS ke awan, penting bagi organisasi ICS untuk bersedia kerana kurang kesediaan boleh membawa kepada kegagalan dalam pelaksanaannya. Oleh itu objektif utama kajian ini adalah untuk mencadangkan Model Kesediaan Pelaksanaan ICS di persekitaran awan (RMfIC) dari perspektif keselamatan maklumat. RMfIC terdiri daripada tiga komponen utama iaitu komponen pertama ialah analisis kesesuaian, komponen kedua, mengukur kesediaan dari perspektif keselamatan maklumat, dan komponen ketiga ialah pengiraan kesediaan organisasi ICS yang juga akan mengenal pasti tahap kesediaan sesebuah organisasi. Sumbangan utama RMfIC adalah organisasi ICS boleh mengenal pasti tahap kesediaan dan menangani cabaran sebelum melaksanakan perkhidamatan ICS di persekitaran awan

ERGONOMICS ASSESSMENT OF WORKSTATION DESIGN IN AUTOMOTIVE INDUSTRY

The purpose of this study is to demonstrate the ability to interpret the various aspects of ergonomics contributions and influences in the manufacturing industry. The application of knowledge and understanding of the ergonomics theories and techniques in the manufacturing industry also will be demonstrated in this study. Besides that, this report will be able us to appreciate the ergonomic role in manufacturing industry and everyday context by showing the ergonomics contribution towards employees’ health and safety in the workplace and tangible or intangible profitability of the company. Adequate posture, work height, normal and maximum working areas are determined for the intended user population. The procedure for determining the workstation dimensions and layout has been explained. The importance of building a mock-up of the designed workstation and its evaluation with representative subjects is emphasized. A case problem (Final Inspection workstation) is discussed to illustrate the workstation design procedure