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Self-organized TiO2 nanotube (TNT) arrays were fabricated by anodic oxidation of titanium foil in three different fluoride electrolytes: ethylene glycol (EG), glycerol, and sodium sulfate (Na2SO4) at different voltage and anodization time. In these electrolytes, the TNTs were produced in ∼ 2 µm long, but at the different diameter. The size of inner diameter can be arranged from the largest to the smallest value in the order of glycerol > EG > Na2SO4. Crystallization of the TNTs by annealing was led to the formation of anatase-TiO2. The sample can be activated under natural sunlight for reduction of hexavalent chromium, Cr(VI) into trivalent chromium, Cr(III). The reduction was thought to occur via synergistic reactions between adsorption and photoreduction. The result demonstrates 100 % of Cr(VI) removal efficiency over the TNTs grown in EG after 120 min. Whereas, only 48 % and 45 % of Cr(VI) can be removed over the TNTs fabricated in glycerol and Na2SO4, respectively. High photocatalytic activity of the ...

Visual design plays an important role in grabbing web users’ attention in an online environment. Previous research has demonstrated that different types of visual design causes different impact towards the end-users. This paper observes the impact of persuasive visual towards users’ first impression, attitudes, and behaviours. It extends existing web visual design by empirically examining the critical roles of the principles of social influence in the form of visual persuasion in motivating users to have a favourable impression of a particular website. Survey data was collected in an experimental study that was conducted online. Structural model assessment is carried out using confirmatory factor analysis (CFA) in conjunction with PLS-SEM analyses. The general analysis of model fit indicates that the two models proposed in this paper surpassed the cut off values for model acceptance with most of the model fit criteria reflects outstanding explanatory power. The result of the analysis indicates that visual persuasion has a big impact in influencing users’ attitudes on the web; strong enough to affect their behavioural intention.

Enzymatic treatment is commonly applied in natural rubber latex (NRL) to produce deproteinized natural rubber (DPNR). The enzyme plays an essential role in degrading the protein molecules into smaller fragments thus easily removed during processing. The DPNR is an alternative raw material of rubber with minimal amount of protein and other non-rubber components which enhances the value of rubber in certain specialized products. Application of DPNR for latex dipped products was initiated as an option to tackle the allergenic issue of NRL glove. However, these ‘low protein latex’ or DPNR-Latex (DPNR-L) have been reported to give uncertain and at times poorer mechanical property and stability. The destabilization of NRL occurs from a build-up of volatile fatty acids (VFA) resulted from microbial metabolic activities. Hence, ammonia is used to stabilize the NRL. In this study, the fundamental approach of making DPNR-L from high ammoniated NRL (HA-NRL) via enzymatic (alcalase and pepsin) and chemical (urea) treatment was conducted. Effect of alcalase, pepsin and urea on the protein content and allergenicity in HA-NRL were studied and discussed. The mechanical property and stability were also evaluated to determine the suitability of the treated HA-NRL use for latex dipped product. Efficiency of alcalase in deactivation of allergenicity was rather good. However alteration in the protein biological structure is detrimental to the latex mechanical property. Meanwhile, the presence of pepsin in HA-NRL caused protein aggregations. As a consequent, insignificant increment of allergenic proteins was detected. Interestingly, the mechanical strength of HA-NRL treated with pepsin was 20% higher than the untreated latex. Treatment with urea shows approximately similar effect as pepsin. Unfortunately, none of these materials could stand alone as protein denaturing agent and mechanical property booster. However, these results proved that the presence of proteins is crucial to NRL mechanical property and that the enzymes and urea could be used to treat HA-NRL based on the purpose of the product application.

The synthesized carbon nanotubes was functionalized with PEG and drug (doxorubicin) was tested on neuroblastoma cells. The treatment was done for 24 and 48 h. The concentration of CNT and doxorubicin were at 2.5, 5, 10 µg/ml and 0.5, 0.1, 0.05 µM, respectively. The result showed the longer time treatment do have effect on the cells viability and the complex functionalized CNT have high cells viability rather than the drug and CNT treatment alone.

Excessive foaming and extensive centrifugation process encountered by purified natural rubber latex (p-NRL) has made this latex not well accepted by the industry as an imperative starting material for latex-based products. In this study, we aim to investigate the feasibility of utilizing single anionic surfactant, sodium dodecyl sulphate (SDS) in combination with urea, a protein denaturant and underwent a single centrifugation process in acquiring p-NRL. Incubation of commercially available high ammoniated natural rubber latex (HA-NRL) with urea in the presence of SDS is known to denature proteins by causing it to unfold and centrifugation process will further facilitate the removal of the unfolded protein from the aqueous serum phase of the HA-NRL. The effect of these processing parameters on the typical latex characteristics, protein separation, nitrogen content, zeta potential (ZP), rheological behaviour, morphology and physical performances of the p-NRL was examined. With specific amount of urea, fitting results of various SDS solutions at 10% (w/w) from surface tension analysis to Langmuir equation resulted in a plateau adsorption capacity. The value was calculated to be approximately 0.0236 gSDS/ grubber, corresponding to about 0.5 phr SDS saturated on the p-NRL rubber surface. Incubation of these chemical mixtures in the HA-NRL with single centrifugation process significantly eradicates most of the proteins, with detrimental effects on the distinctive p-NRL properties. Although SDS creates synergizing effect with urea for protein denaturation process, it nevertheless did not create a destabilization phenomenon to the p-NRL as the zeta potential analysis demonstrated negatively charged values over the entire pH range. Remarkable rheological performances of the p-NRL suggested that the system is proportionately stabilized by the surfactant adsorptions, which is concurrent with the zeta potential analysis. Observing the p-NRL particles in latex state and in the dried film through Environmental Scanning Electron Microscopy (ESEM) and Field Emission Scanning Electron Microscopy (FESEM) revealed a unique particle packing arrangements. It was hypothesized that the processing parameters in producing p-NRL has a pronounced influence to both particle morphologies. The film formation of p-NRL compounded with natural-based filler was studied and compared with HA latex film in term of physical properties.

This paper describes the chemical deproteinization process of natural rubber latex (NRL) using chemical denaturants namely urea and sodium dodecyl sulfate (SDS). Commercial high ammoniated natural rubber latex (HANRL) was incubated with both denaturants – urea and SDS for selected period of time before centrifugation and characterization. The role of SDS in NRL deproteinization process was further elucidated by manipulating the concentration of SDS at 0.3 phr and 0.5 phr during the incubation process. It was found that the physical properties of NRL especially stability, were governed by the amount of SDS, whereby higher concentration of SDS used led to greater NRL stability. However, too much concentration of SDS in the system might cause detrimental effect on the properties of low protein NRL. The effects of additional anionic surfactant namely potassium laurate on the physical properties of low protein NRL and its stabilization were also scrutinized. Characterizations include nitrogen determination by ...

Electrocoagulation (EC) is a promising technology that extensively used to remove fluoride ions efficiently from industrial wastewater. However, it has received very little consideration and understanding on mechanism and factors that affecting the fluoride removal process. In order to determine the efficiency of fluoride removal in EC process, the effect of operating parameters such as voltage and electrolysis time were investigated in this study. A batch experiment with monopolar aluminium electrodes was conducted to identify the model of fluoride removal using empirical model equation. The EC process was investigated using several parameters which include voltage (3 – 12 V) and electrolysis time (0 - 60 minutes) at a constant initial fluoride concentration of 25 mg/L. The result shows that the fluoride removal efficiency increased steadily with increasing voltage and electrolysis time. The best fluoride removal efficiency was obtained with 94.8 % removal at 25 mg/L initial fluoride concentration, voltage of 12 V and 60 minutes electrolysis time. The results indicated that the rate constant, k and number of order, n decreased as the voltage increased. The rate of fluoride removal model was developed based on the empirical model equation using the correlation of k and n. Overall, the result showed that EC process can be considered as a potential alternative technology for fluoride removal in wastewater.Electrocoagulation (EC) is a promising technology that extensively used to remove fluoride ions efficiently from industrial wastewater. However, it has received very little consideration and understanding on mechanism and factors that affecting the fluoride removal process. In order to determine the efficiency of fluoride removal in EC process, the effect of operating parameters such as voltage and electrolysis time were investigated in this study. A batch experiment with monopolar aluminium electrodes was conducted to identify the model of fluoride removal using empirical model equation. The EC process was investigated using several parameters which include voltage (3 – 12 V) and electrolysis time (0 - 60 minutes) at a constant initial fluoride concentration of 25 mg/L. The result shows that the fluoride removal efficiency increased steadily with increasing voltage and electrolysis time. The best fluoride removal efficiency was obtained with 94.8 % removal at 25 mg/L initial fluoride concentration, volta...

Gold nanoparticles (AuNPs) are considered as one of the most stable metal nanoparticles and have received immense research’s interest due to their size-related electronic, magnetic and optical properties such as quantum size impact. However, AuNPs tend to form agglomeration in solution. Hence, detailed study on colloidal stability is crucial in preventing the agglomeration of AuNPs. The AuNPs was prepared by using sodium citrate reduction method before dispersing the sample in the organic media, dimethylformamide (DMF) prior to transmission electron microscopy (TEM) and Zeta Sizer analysis. The AuNPs were also dispersed in aqueous media which subsequently being characterized using UV-Vis spectroscopy and Zeta Sizer analysis. The effect of temperature was investigated in order to identify the hydrodynamic size and the stability of the AuNPs in both DMF and aqueous media. The presence of AuNPs in solution was confirmed by the maximum absorbance peak at the wavelength of 552 nm. From the TEM analysis, the AuNPs were dispersed well in the organic media which the nominal particles size distribution centered at 3.5 nm. The optimum temperature for AuNPs in both organic and aqueous media was at ≤ 35 °C where the zeta potential showed -30.7 mV and -36.7 mV respectively. From the observations on hydrodynamic particles size, it was shown that the particles size had the smallest size of 20 nm at 25°C and biggest size of 132 nm at 55°C in aqueous media. While particles size in DMF showed, the smallest size and biggest size were 36 nm at 25°C and 158 nm at 55°C, respectively. Thus, the AuNPs in aqueous media showed comparatively smaller size of particles compare to the AuNPs in DMF.

Bayesian Network (BN) has been regarded as a successful representation of inter-relationship of factors affecting human behavior during an emergency. This paper is an extension of earlier work of quantifying the variables involved in the BN model of human behavior during an evacuation using a well-known direct probability elicitation technique. To overcome judgment bias and reduce the expert’s burden in providing precise probability values, a new approach for the elicitation technique is required. This study proposes a new fuzzy BN approach for quantifying human behavior during an evacuation. Three major phases of methodology are involved, namely 1) development of qualitative model representing human factors during an evacuation, 2) quantification of BN model using fuzzy probability and 3) inferencing and interpreting the BN result. A case study of three inter-dependencies of human evacuation factors such as danger assessment ability, information about the threat and stressful conditions are used to illus...

This paper represents the hybrid system performance compare to different bit rate with direct detection techniques. Implementation of EDFA in hybrid system which is increasing the fiber distance for subscriber requirement for high connectivity and speed data transmission. We have to used Modified Double Weight (MDW) code as signature code for flexible, scalable together enhance the performance and improve the security of the system. Proposed hybrid system provides high bandwidth for the immense users. The different detection techniques apply to increased capacity, accuracy and ability to operate simultaneously. The result shows that using EDFA provides 2.5×−10 BER at distance 6km where without EDFA 3.6×10−07. According to the analysis results, the proposed direct detection technique improves the signal quality with low optimum gain of the system. Thus, this system is considered as encouraging solution for the optical access network.

Research related to the first impression has highlighted the importance of visual appeal in influencing the favourable attitude towards a website. In the perspective of impression formation, it is proposed that the users are actually attracted to certain characteristics or aspects of the visual properties of a website, while ignoring the rests. Therefore, this study aims to investigate which visual strongly appeals to the users by comparing the impact of common visuals with the persuasive visuals. The principles of social influence are proposed as the added value to the persuasiveness of the web visuals. An experimental study is conducted and the PLS-SEM method is employed to analyse the obtained data. The result of the exploratory analyses demonstrated that the structural model has better quality when tested with persuasive data sample compared to non-persuasive data sample, evident with stronger coefficient of determination and path coefficients. Thus, it is concluded that persuasive visual provides better impact towards users’ attitude and behavioural intention of a website.

Carbon nanotubes (CNT) have potential biomedical applications, and investigations are shifting towards the production of such nanotubes using renewable natural sources. CNTs were synthesized at various temperatures of 700, 750, 800, 850 and 900 °C, respectively, using a local fermented food known as “tapai ubi” or fermented tapioca as a precursor. The liquid part of this fermented food was heated separately at 80°C and channeled directly into the furnace system that employs the thermal chemical vapor deposition (CVD) method. Ferrocene, which was the catalyst was placed in furnace 1 in the thermal CVD process. The resulting CNTs produced from the process were studied using field emission scanning electron microscopy (FESEM) and raman spectroscopy. The FESEM images showed the growth morphology of the CNTs at the different temperatures employed. It was observed that the higher the synthesis temperature up to a point, the diameter of CNTs produced, after which the diameter increased. CNTs with helical structu...

Freestanding ZrO2 nanotubes (ZNTs) were produced using a simple anodization method in fluorinated ethylene glycol electrolyte containing 1 ml 1 M K2CO3. The pH of the bath was kept constant at 8. The potassium carbonate (K2CO3) was added into electrolyte to promote the detachment of anodic ZrO2 film from the underlying zirconium (Zr) substrate. The poor adherence of ZNTs layer was due to generation of CO2 gas that was thought to occur between metal|oxide interfaces. The effect of anodization voltages towards the detachment of ZNTs layer was systematically studied at 20 V, 40 V, 50 V and 60 V for 1 hour. The formation of CO2 gas is a function of anodization voltage, in which at 60 V, a good anodic film separation seen due to higher formation of CO2 gas. A preliminary study shown the capability of ZNTs in removing 5 ppm of Cr(VI) aqueous solution under illumination of UV light.

Sialon and AISI 420 martensitic stainless steel were diffusion bonded in order to study the effect of bonding time on reaction layer’s growth. Joining of these materials was conducted at 1200°C under a uniaxial pressure of 17 MPa in a vacuum ranging from 5.0 to 8.0×10−6 Torr with bonding time varied for 0.5, 2, and 3 h. Thicker reaction layer was formed in longer bonded sample since the elements from sialon could diffuse further into the steel. Sialon retained its microstructure but it was affected at the initial contact with the steel to form the new interface layer. Diffusion layer grew toward the steel and it was segregated with the parent steel as a result of the difference in properties between these regions. The segregation formed a stream-like structure and its depth decreased when the bonding time was increased. The microstructure of the steel transformed into large grain size with precipitates. Prolonging the bonding time produced more precipitates in the steel and reduced the steel thickness as ...

This present study was conducted to investigate the effectiveness of catalytic wet peroxide oxidation (CWPO) process using photo-Fenton method and the used of mining sand as support catalyst as well as to determine the optimum parameters and effect of catalyst wt%, pH, H2O2 concentration, initial dye concentration and catalyst dosage on RB 5 degradation. The Fe/mining sand was prepared by impregnation technique and a solar degradation of RB 5 carried out by mean photo-Fenton reaction promoted by solar energy. The dye degradation was monitored during the experimental runs through UV/Vis spectrophotometer. In this process, the reaction condition were optimized at 0.4 of catalyst wt%, pH 2, 4 mM of H2O2 concentration and 0.5 g of catalyst dosage which achieved degradation efficiency at 100% for the three experiments except catalyst dosage which achieved 97.54% respectively within 180 min. The degradation of RB 5 also decreased with the increasing of dye concentration with 10 mg/L achieved the optimum degrada...

The development of new strategies to efficiently synthesize biodiesel is of extreme important. This is because biodiesel has been accepted worldwide as an alternative fuel for diesel engines. Biodiesel as alkyl ester derived from vegetable oil has considerable advantages in terms of environmental protection. The diminishing petroleum reserves are the major driving force for researchers to look for better strategies in producing biodiesel. The main hurdle to commercialization of biodiesel is the cost of the raw material. Biodiesel is usually produced from food-grade vegetable oil that is more expensive than diesel fuel. Therefore, biodiesel produced from food-grade vegetable oil is currently not economically feasible. Use of an inexpensive raw material such as waste cooking palm oil and non edible oil sea mango are an attractive option to lower the cost of biodiesel. This study addresses an alternative method for biodiesel production which is to use an enzymatic approach in producing biodiesel fuel from low cost feedstock waste cooking palm oil and unrefined sea mango oil using immobilized lipase Lipozyme TL IM. tert-butanol was used as the reaction medium, which eliminated both negative effects caused by excessive methanol and glycerol as the byproduct. Two variables which is methanol to oil molar ratio and enzyme loading were examine in a batch system. Transesterification of waste cooking palm oil reach 65% FAME yield (methanol to oil molar ratio 6:1 and 10% Novozyme 435 based on oil weight), while transesterification of sea mango oil can reach 90% FAME yield (methanol to oil molar ratio 6:1 and 10% Lipozyme TLIM based on oil weight).

Automatic Skin Lesion Diagnosis (ASLD) allows skin lesion diagnosis by using a computer or mobile devices. The idea of using a computer to assist in diagnosis of skin lesions was first proposed in the literature around 1985. Images of skin lesions are analyzed by the computer to capture certain features thought to be characteristic of skin diseases. These features (expressed as numeric values) are then used to classify the image and report a diagnosis. Image segmentation is often a critical step in image analysis and it may use statistical classification, thresholding, edge detection, region detection, or any combination of these techniques. Nevertheless, image segmentation of skin lesion images is yet limited to superficial evaluations which merely display images of the segmentation results and appeal to the reader's intuition for evaluation. There is a consistent lack of quantitative measure, thus, it is difficult to know which segmentation present useful results and in which situations they do so. If segmentation is done well, then, all other stages in image analysis are made simpler. If significant features (that are crucial for diagnosis) are not extracted from images, it will affect the accuracy of the automated diagnosis. This paper explore the existing quantitative measure in image segmentation ranging in the application of pattern recognition for example hand writing, plat number, and colour. Selecting the most suitable segmentation measure is highly important so that as much relevant features can be identified and extracted.

The trend of using renewable sources such as palm oil as raw material in radiation curing is growing due to the demand from the market to produce a more environmental friendly product. In this study, the radiation curable process was done using epoxy acrylate and urethane acrylate resins which are known as epoxidised palm olein acrylate (EPOLA) and palm oil based urethane acrylate (POBUA), respectively. The purpose of the study was to investigate curing properties and the application of this UV-curable palm oil resins for wood coating. Furthermore, the properties of palm oil based coatings are compared with the petrochemical-based compound such as ebecryl (EB) i.e. EB264 and EB830. From the experiment done, the resins from petrochemical-based compounds resulted higher degree of crosslinking (up to 80%) than the palm oil based compounds (up to 70%), where the different is around 10-15%. The hardness property from this two type coatings can reached until 50% at the lower percentage of the oligomer. However, the coatings from petrochemical-based have a high scratch resistance as it can withstand at least up to 3.0 Newtons (N) compared to the palm oil-based compounds which are difficult to withstand the load up to 1.0 N. Finally, the test on the rubber wood substrate showed that the coatings containing benzophenone photoinitiator give higher adhesion property and their also showed a higher glosiness property on the glass substrate compared to the coatings containing irgacure-819 photoinitiator. This study showed that the palm oil coatings can be a suitable for the replacement of petrochemicals compound for wood coating. The palm oil coatings can be more competitive in the market if the problems of using high percentage palm oil oligomer can be overcome as the palm oil price is cheap enough.

The effects of overcrowding have become a major concern for event organizers. One aspect of this concern has been the idea that overcrowding can enhance the occurrence of serious incidents during events. As one of the largest Muslim religious gathering attended by pilgrims from all over the world, Hajj has become extremely overcrowded with many incidents being reported. The purpose of this study is to analyze the nature of human emotion and negative behavior resulting from overcrowding during Hajj events from data gathered in Malaysian Hajj Experience Survey in 2013. The sample comprised of 147 Malaysian pilgrims (70 males and 77 females). Utilizing a probabilistic model called Bayesian network, this paper models the dependence structure between different emotions and negative behaviors of pilgrims in the crowd. The model included the following variables of emotion: negative, negative comfortable, positive, positive comfortable and positive spiritual and variables of negative behaviors; aggressive and hazardous acts. The study demonstrated that emotions of negative, negative comfortable, positive spiritual and positive emotion have a direct influence on aggressive behavior whereas emotion of negative comfortable, positive spiritual and positive have a direct influence on hazardous acts behavior. The sensitivity analysis showed that a low level of negative and negative comfortable emotions leads to a lower level of aggressive and hazardous behavior. Findings of the study can be further improved to identify the exact cause and risk factors of crowd-related incidents in preventing crowd disasters during the mass gathering events.

Antimony zinc borophosphate glass were prepared with the composition of 20ZnO-30B2O3-xP2O5-(50-x)Sb2O3-2Fe2O3 (0≤x≤50 mol%) using the melt quenching method. The starting materials were mixed and preheat for 30 minutes and transfer into high temperature furnace for melting. The structure of samples were measured using Fourier-Transform Infrared (FT-IR) Spectroscopy. The spectra showed that network structure in the samples are mainly based on P=O, PO2, P-O, B-O-B and B-O units. With increasing P2O5 content, the vibration of P-O tends to shift towards lower wavenumber. Meanwhile, the luminescence was studied using Photoluminescence (PL) Spectroscopy. The samples were excited at specific wavelengths (265 - 300 nm). The emission profiles were obtained to study the energy transfer process. Luminescence of violet colour from samples were also recorded to correlate with PL results.

The objectives of this quantitative survey research were (1) to establish the level of scientific reasoning (SR) skills among science, mathematics and engineering (SME) undergraduates in Malaysian Institute of Higher Learning (IHL); (b) to identify the types of instructional methods in teaching SME at universities; and (c) to map instructional methods employed to the level of SR skills among the undergraduates. There were six universities according to zone involved in this study using the stratification random sampling technique. For each university, the faculties that involved were faculties which have degree students in science, mathematics and engineering programme. A total of 975 students were participated in this study. There were two instruments used in this study namely, the Lawson Scientific Reasoning Skills Test and the Lecturers' Teaching Style Survey. The descriptive statistics and the inferential statistics such as mean, t-test and Pearson correlation were used to analyze the data. Findings of the study showed that most students had concrete level of scientific reasoning skills where the overall mean was 3.23. The expert and delegator were dominant lecturers' teaching styles according to students' perception. In addition, there was no correlation between lecturers' teaching style and the level of scientific reasoning skills. Thus, this study cannot map the dominant lecturers' teaching style to the level of scientific reasoning skills of Science, Mathematics and Engineering undergraduates in Malaysian Public Institute of Higher Learning. Nevertheless, this study gave some indications that the expert and delegator teaching styles were not contributed to the development of students' scientific reasoning skills. This study can be used as a baseline for Science, Mathematics and Engineering undergraduates' level of scientific reasoning skills in Malaysian Public Institute of Higher Learning. Overall, this study also opens an endless source of other researchers to investigate more areas on scientific reasoning skills so that the potential instructional model can be developed to enhance students' level of scientific reasoning skills in Malaysian Public Institute of Higher Learning.