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Borate glasses with composition 50B2O3 – (25-x) Bi2O3 – 25ZnO – xTiO2 where x = 0, 1, 2, 3, 4 (mol%) were succesfully fabricated using a convensional melt-quenching technique aimed at tailoring glass suitable for a low loss optical fiber fundament. For this purpose, glasses were characterized for their density, refractive index, reflectance, UV-Vis absorption and FTIR spectra. Density measurement was carried out by applying Archimedes principle. Refractive index was measured using Brewster’s angle method. UV-Vis spectrum was recorded within the range of 200-1100 nm and FTIR measurement was measured at IR range. Combining the spectra data recorded both from UV-Vis–NIR and FTIR, the theoretical minimum loss of the glass was obtained. In addition, the band gap energy of the present glasses was also calculated. From these data, it can be derived many other glass properties such as Oxygen Packing Density (OPD), ionic radius, and polaron radius.

This paper presents the optical properties of erbium doped tellurite glasses with the composition of 55TeO2-2Bi2O3-35ZnO-5PbO-(3-x)Na2O-xEr2O3 where x = 0, 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0 mol% . Refractive index of the glasses was measured using Brewster’s angle method and their optical absorption spectra were measured in spectral range 200 – 1100 nm recorded at room temperature. The results show that the glass refractive index increases with the increase of Er3+ ion content in the glass and the optical band gap energy decreases with the increase of erbium content in the glass.

This work was carried out as a preliminary study of electrospun LiFePO4/CA fibers. Cellulose acetate (CA) and LiFePO4 solutions were prepared separately using mixed solvent of acetone and water, prior to the electrospinning process. Then, electrospinning parameters including solution concentration, distance tip to collector, pump rate, and needle diameter size were optimized. Brunauer Emmett Teller (BET) was used to determine the surface area of CA fibers. Viscosity of CA solution was obtained by viscometer. LiFePO4/CA fibers were stabilized and carbonized at different temperature. The surface morphology and microstructure of the obtained LiFePO4/ CA fibers were then characterized using scanning electron microscope (SEM). In this work, it is shown that different electrospinning parameter, solution concentration and solution viscosity gives different fibers diameter and distribution. Moreover, the stabilization and carbonization temperature of LiFePO4/CA fibers may also affect the fibers microstructure.

The cationic chemosensor based on organic compound bearing an aminophenol moiety as a receptor for metal analyte and a cinnamaldehyde moiety as chromophoric fragment has been developed. In this work, we report the colorimetric sensing of nitrophenyl cinnamaldehyde derivative, namely methyl-3-(2-hidroxy-5-nitrophenyl amino)-3-phenylpropanoate, towards a variety of metal cations, such as Cu 2+ , Fe 3+ , Ni 2+ and Zn 2+ . The cation sensing abilities of the sensor were observed for Cu 2+ and Fe 3+ with a color change from colorless to pink and faint yellow, respectively, The characteristic UV-Vis spectra changes were observed upon addition of Cu 2+ and Fe 3+ cations. The hypsochromic absorption spectra shifts were obtained, indicating the cations and sensor complexations had formed. A metal-to-ligand-charge-transfer (MLCT) had occurred and the charge density of the sensor changed resulting in appearance of new absorption peaks in the UV-Vis spectra and color changes of the sensor solution upon addition of the Cu 2+ and Fe 3+ .

The limited shelf life of carbon prepreg waste (CPW) from component manufacturing restricts its use as a composite reinforcement fibre on its own. However, CPW can be recycled with glass fibre (GF) reinforcement to develop a unique remediate material. Therefore, this study fabricated (1) a glass fibre-carbon prepreg waste reinforced polymer hybrid composite (GF-CPW-PP), (2) a polypropylene composite (PP), (3) a carbon prepreg waste reinforced composite (CPW-PP), and (4) a glass fibre reinforced composite (GF-PP) and reported their degradation and residual tension properties after immersion in water. The polymer hybrid composites were fabricated via extrusion technique with minimum reinforce glass-carbon prepreg waste content of 10 wt%. The immersion test was conducted at room temperature using distilled water. Moisture content and diffusion coefficient (DC) were determined based on water adsorption values recorded at 24-h intervals over a one-week period. The results indicated that GF-PP reinforced composites retained the most moisture post-168 h of immersion. However, hardness and tensile strength were found to decrease with increased water adsorption. Tensile strength was found to be compromised since pores produced during hydrolysis reduced interfacial bonding between glass fibre and prepreg carbon reinforcements and the PP matrix.

Food packaging has seen a growth in the use of materials derived from renewable resources such as poly(lactic acid) (PLA). However, the initial costs to produce bioplastics are typically high. Tropical fruit waste as naturally sourced fibres, such as jackfruit skin, can be used as a cost-reducing filler for PLA. The main objective in this study is to fabricate a low-cost natural fibre-reinforced polymer that potentially applies in packaging with the aid of bleaching treatment. The treatment shows a rougher surface fibre in Scanning electron microscopy (SEM) micrographs and it is expected to have better mechanical locking with the matrix, and this is found similar with a Fourier-transform infrared spectroscopy (FTIR) analysis. Unfortunately, fibre insertion does find low tensile performances, yet bleached-fibre composites improved its performance significantly. A similar situation was found in the thermal characterization where a low-thermal stability natural fibre composite has lower thermal behaviour and this increased with bleaching treatment. Besides, bleached-fibre composites have a longer service period. Besides, a 15 wt% thymol insertion inhibits the growth of Gram-positive bacteria in the composites and the non-treated fibre composite has better thymol effects. The 30 wt% of the bleached-fibre insertion composite has a high potential to reduce the cost of bioplastic products with minimum alterations of overall performances.

Introduction: Despite advances in the management of diabetes, the rate of control of diabetes in the population remains modest. Perception of diabetes control is a key to patient empowerment. The aim of this study was to describe the perception of diabetes control among patient with poorly controlled diabetes. Materials and method: A cross sectional study was done involving 276 patients with type 2 diabetes mellitus in the out-patient settings. After obtaining an informed consent, the socio-demography and medical history of each patient was recorded. Their most recent available blood investigations were documented. Patients were then asked on their perception of diabetes control whether it was excellent, moderate or poor. Analyses were descriptive and exploratory. Results: The median age of subjects was 56.0 (48.0,62.0) years old, with a median duration of diabetes of 8 (4,13) years. The median HbA1C was 9.5 (8.3,11.4)% with a fasting blood sugar of 9.7 (7.1,13.8) mmol/L. Despite having poor HbA1C, 28.4% of patients perceived that their diabetes control was excellent; 58.9% perceived moderate and only 12.7% accurately perceived poor control. The reverse relationship between perception of disease and education may indicate that other factors such as effective communication might need to be considered. The absence of association between perception and duration of diabetes may suggest that information given to patient over the years had poor impact on their understanding of disease control. Conclusion: This study demonstrated that there was presence of discordance between perception of diabetes control and HbA1C. Identifying the discordance between perception of diabetes control and HbA1C should be the first step in delivering a personalized diabetes education for patient.

Objectives As is true for other chronic illnesses, perception of disease control is pivotal to patient empowerment in diabetes care. This study aimed to describe the perception of diabetes control by patients with poor glycated hemoglobin (A1C) levels so as to explore the relationship between perception and various sociodemographic and disease characteristics and to measure the patients' knowledge, attitudes and practices in diabetes care. Methods A cross-sectional study was made involving 276 patients with type 2 diabetes mellitus. After obtaining informed consent, their sociodemographics, medical histories and most recent available blood investigations were documented. Patients were asked about their perceptions of diabetes control—whether it was excellent, moderate or poor. A Malay-language knowledge, attitudes and practice questionnaire was administered to respondents. Analyses were descriptive and exploratory. Results The median age of the subjects and the durations of diabetes were 56 (interquartile range, 48–62) years and 8 (interquartile range, 4–13) years, respectively. The median A1C level was 9.5% (interquartile range, 8.3%–11.4%). Despite having poor A1C levels, 28.4% of patients perceived that their diabetes control was excellent; 58.9% perceived it as moderate, and only 12.7% accurately perceived it as poor. A significant number of those with higher education had wrong perceptions, indicating that other factors, such as effective communication, need to be considered. The absence of an association between perception and duration of diabetes suggests that information given over the years did not contribute to patients' understanding of disease control. Younger patients had better knowledge scores. Those with higher education levels had higher quartiles of knowledge and attitude but not practice scores. Conclusions This study demonstrated discordance between perceived diabetes control and actual A1C levels, which may hinder effective diabetes care.

This paper presents the effect of TiO2 addition on the physical and optical properties of TeO2-ZnO-Na2O glasses. For this study, glasses with the compositions of 63.16TeO2 - (31.57-x) ZnO – 5.26 Na2O – xTiO2 (where x = 1.06, 2.11, 3.16, and 4.22 mol%) were prepared with melt quenching technique. Glasses were characterized in order to obtained glass density, refractive index, and absorption spectra ranging from UV to IR regions. From these basic data, we have evaluated the values of molar volume, oxygen packed density, polaron radius, inter-ionic distance, field strength, and optical band gap. It was observed that incorporating TiO2 into the glasses to substitute ZnO have resulted in decreasing the values of density, inter-ionic distance, and field strength; and yet increasing molar volume, oxygen packed density and polaron radius. The structural units building the glass networks have also been evaluated.

Characterization of soda-lime has been done with aluminum doping on soda-lime glass using an electric-field-assisted solid-state ion exchange method (EFASSiE) to produce an aluminum coating on the glass. EFASSIE is an ion-exchange method that enables the doping of glass surfaces with aluminum ions. The variations used in ion exchange are temperature and electric fields. Variations of temperature start from 400°C until 500°C, increased temperature will cause the ions inside the glass to vibrate and forming a gap, allowed aluminum ions to penetrate into the glass structure. Variations of electric field start from 300-500 V/mm. Electric field that been exposed to the soda lime glass will accelerate the penetration process of the aluminum ion and pushes the smallest ion out of the glass. The results of the soda-lime glass characterization test shows that the greater the value of temperature and electric field used, refractive index of the soda lime after the ion exchange will increase. Otherwise, glass transmittance after ion exchange process has a relatively small compared to the glass before the process. Soda-lime glass Microstructure after the ion exchange process are known from SEM-EDX test, the result proved that alumunium ion penetrate into the soda-lime glass.

Fiber Metal laminates, FML, is a combination of metal with fiber/resin laminates and it is a well-known application in composite laminates due to its dimension stability and properties consistency. Generally, the strength of these laminates systems is much depends on the mechanical interlocking mechanism between the metal surface and the composite laminates. Therefore, surface treatment is needed to enhance the laminates strength. In this research, aluminum plates with different surface roughness were laminated with carbon-fiber/epoxy laminates. The strength of these hybrid systems was then characterized to study the effect of surface roughness on the interfacial strength. It shows that the higher surface roughness will result in better interfacial interaction between the metal surface and the fiber laminates.

Fibre-metal-laminated composites that consist of aluminium and carbon fibre/epoxy was widely use in engineering fields such as in aerospace and civil application. An issue arise for this laminate systems is that aluminium surfaces must be treated to ensure the effectiveness of load transfer mechanism in the interfacial region. In this research, the effect of anodized layer on the aluminium surface towards strength of the carbon fibre-aluminium-laminated composites was studied. Aluminium 6061-T6 was anodized using phosphoric acid as electrolyte and different anodizing voltage to produce different surface morphology. The surface roughness and morphology were determined via Atomic Force Microscopy and its wettability was determined by Static Contact Angle. Then, anodized aluminium was laminated with carbon fibre/epoxy system via vacuum bagging techniques. It shows that the strength of laminated composite with anodized surface increases up to 26% compared to laminates without anodized surfaces. Furthermore, the failure mechanism of laminated composite with anodized surface resulted in partial adhered failure instead of adhesive failure. These show that anodized surfaces contributes to the effectiveness of load transfer mechanism in fibre-metal-laminates composites.

An optical fiber sensor based on evanescent wave absorption designed for measuring glucose solution consentration was proposed. The sensor was made to detect absorbance of various wavelength in the glucose solution. The sensing element was fabricated by side polishing of multimode polymer optical fiber to form a D-shape. The sensing element was immersed in different concentration of glucoce solution. As light propagated through the optical fiber, the evanescent wave interacted with the glucose solution. Light was absorbed by the glucose solution. The larger concentration the glucose solution has, the more the evanescent wave was absorbed in particular wavelenght. Here in this paper, light absorbtion as function of glucose concentration was measured as function of wavelength (the color of LED). We have shown that the proposed sensor can demonstrated an increase of light absorption as function of glucose concentration.

Evanescent wave field has been studied for the purpose of tailoring fiber sensor capable of detecting lindane concentration in a solution. The mounted fiber was optically polished such that part of the fiber clad is stripped off. To study the evanescent wave field absorption in lindane solution, the unclad fiber was immersed in the solution. Light coming out of the fiber was studied at different wavelength each for different lindane concentration. It was shown that evanescent wave field absorption is stronger at wavelength corresponding to lindane absorption band as has been shown from absorption studies lindane in UV-VIS-NIR spectrophotometer.

Tellurite glasses with compositions of 55TeO2 - (41- x) ZnO-2Bi2O3-2Na2O-xPbO where x = 1.0, 1.5, 2.0, and 2.5% mole (Pb:TZBN glasses) were prepared by melting the mixture at 900°C and quenched rapidly. IR spectra were recorded in the range 400 cm-1 and 4000 cm-1. Analyses were carried out to study the effect of PbO incorporation into the glasses to the shift the main absorption vibrational spectra. The results were then analysed in term of coordination number of Pb as well as the change in mass reduction.

Physical and optical properties of lead telluride (Pb:TZBN) glasses with composition 55TeO2-(41-x)ZnO-2Bi2O3-2Na2O-xPbO where x = 1.0, 1.5, 2.0, 2.5% mol are presented. UV-VIS-NIR spectra of the glasses in the range of 300 - 800 nm along with their densities and refractive indices at 746 nm were recorded at room temperature. The optical bandgap energy (Eg) has been calculated from the fitting of Tauc plot. On the basis of these results we found that with the increase of Pb2+ content, their refractive indices are increased while their optical bandgaps are decreased. From this experiment, no distinct relationship between the Pb2+ content variation and the electronic polarizability (αO2-) as well as their optical basicity values (A) were observed.