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A control chart is one of the most important techniques used to monitor processes of variability in the manufacturing data. However, conventional charts are relatively not suitable to deal with crisp data. Fuzzy charts are inevitable to evaluate the process with fuzzy data. Nevertheless, much of the data used in daily life cannot be used as a type-1 fuzzy number due to the complexity and uncertainty of information. It is suggested that type-2 fuzzy numbers are more capable in detecting the meaning of process shifts. This paper aims to develop interval type-2 fuzzy (IT2F) Exponentially Weighted Moving Average (IT2F-EWMA) control charts as a new method where the advantages of lower membership and upper membership, which can capture sensitivity and variability in manufacturing data. In the proposed method, we also employed the Best Nonfuzzy Performance method as the defuzzification method instead of the typical centroid method. In order to confirm the performance of the proposed control chart, the average run length (ARL) is calculated and compared to the other three charts. To test the performance of the proposed EWMA, twenty samples were analysed to identify the defects in the fertilizers’ production. Based on the result of the conventional chart, 8 out of 20 samples are “uncontrolled”. In contrast, the type-1 chart found 16 samples are “uncontrolled”, whereas IT2F-EWMA found 18 samples are “out of control”. Consequently, it is proven that IT2F-EWMA is the best method to be used in dealing with vague and fuzzy data since it is more precise and vulnerable. Lastly, the ARL test shows that IT2F-EWMA charts outperform the other control charts.

Introduction: Retirees undergo role transition after leaving their job. Hence, occupational therapists may assess retirees’ roles to identify their current roles’ satisfaction and anticipation. As Malaysian culture and language differed from the origin of the Role Checklist, this study aimed to translate and validate the Role Checklist into the Malay version cross-culturally.Methodology: A forward–backwards translation was conducted, followed by pilot testing among 9 experts and 20 retirees. A cross-sectional study was done among 122 Malaysian retirees to identify the translated instrument’s test–retest reliability, discriminant and convergent validity.Findings: The Role Checklist – Malay achieved almost perfect Average Content Validity Index (0.95–0.98) and Average Face Validity Index (0.92–0.96), good to excellent test–retest reliability with intraclass correlation coefficients = 0.654–0.976, and moderate to perfect agreement of Cohen’s kappa (0.620–1.00). Additionally, there were significant differences in the total number of roles (p< 0.001) and total desired future roles (p< 0.001) between retirees living in the community and institution. The total number of roles was positively correlated with the SWLS – Malay (rs= 0.593, p< 0.001), EQ-5D-3L – Malay (rs= 0.366, p< .001) and MSPSS – Malay (rs= 0.314, p< 0.001).Conclusion: The Role Checklist – Malay was a valid and reliable instrument among Malaysian retirees.

Graphical abstract:

Mild steel is often used as a construction material in the industry because of its relatively low price. However, due to its low corrosion resistance, some form of a protective film should be applied to prevent it from rusting in the corrosive environment. Thiosemicarbazone is one of the Schiff base ligands that can inhibit corrosion due to the presence of electronegative atoms such as N, S, and π electrons that can cause an efficient adsorption on the mild steel surface. This research aims to synthesise of 2-chloroacetophenone 4-ethyl-3-thiosemicarbazone (2ClAcTSC) and the structure was confirmed using an elemental analyser, UV–Vis, NMR and ATR-FTIR. The inhibitive effects of 2ClAcTSC were studied on mild steel in 1 M HCl and H2SO4by using the weight loss method and Scanning Electron Microscopy (SEM). It was found that the 2ClAcTSC has better effectiveness in HCl rather than H2SO4solution. Moreover, the inhibition efficiency increases as the inhibitor concentration increases. The SEM results verified that the inhibitor had been adsorbed on the mild steel surface to form a protective layer. Density Functional Theory (DFT) computations are performed to correlate inhibitor efficiency with intrinsic molecular parameters. The study revealed that the results obtained are consistent with the experimental data reported.

This paper aims to review the obstacles faced by individuals in planning a prosperous retirement and to suggest some improvements to encourage the individuals and governments in achieving steadfast finances during the current economic crisis. This paper has utilised a critical review technique on current and emerging systems of retirement planning in Malaysia. We found the two main factors of retirement planning, perceived financial literacy and perception of health, from the literature. Paradoxically, we found limited ways on how the retirement planning practices can assist Malaysians achieve the significance levels of retirement planning which are defined as the successful retirement planning indicators. Contributions of this study are to provide a foresight framework to solve the current Malaysian problems in managing their retirement plan: low salary, late planning, high bankruptcy cases, high household debt and low savings; and suggest a solution framework of study the retirement systems. The literature on retirement planning management has expanded. However, future research is necessary to align the volatile economic conditions and the technological changes.

In the present work, the surface morphology and electrical characteristic of different doping ratio of reduced Graphene Oxide (rGO) in Titanium Oxide solution with different organic dyes (turmeric and beetroot) were studied. The Titanium Dioxide (TiO2) solution and reduced Graphene Oxides (rGO) were synthesized by using precipitation-peptization method and chemical reagent, respectively. The TiO2-rGO thin film was deposited on the glass substrate by using doctor-blade technique. The surface morphology and electrical characteristic were measured by using Scanning Electron Microscope (SEM) and Keitheley 2450 Source Meter, respectively. Experimental results showed that 0.3 wt% rGO with turmeric dye resulted the highest value of open voltage (Voc) and short circuit current (Isc) of Dye-sensitized Solar Cells (DSSC).

ABSTRACTHydrogel dressings should be adhesive and elastic, while providing excellent functional and aesthetic features. Owing to weak intermolecular forces, various measures are undertaken to improve the hydrogel mechanical properties. Thermo-responsive poly(2-(2-methoxyethoxy)ethyl methacrylate) (poly(MEO2MA)) hydrogel fabricated with different amounts of di(ethylene glycol) dimethacrylate (DEGDMA) cross-linker was characterised using texture profile analysis. More cross-linking sites incorporated within the hydrogel limit the swelling ability where 1.0 and 10 mol-% of DEGDMA swell by 8.03 and 1.92 times, at 5°C. Hydrogel textural and tensile property correlated with the cross-linker amount. Meanwhile, network structure disentanglement within swollen hydrogel reduced the force required for deformation. Thus, the swelling behaviour, textural and tensile properties were investigated to discern the possible biomedical applications suitable for this hydrogel.

Hydrogel dressings should be adhesive and elastic, while providing excellent functional and aesthetic features. Owing to weak intermolecular forces, various measures are undertaken to improve the hydrogel mechanical properties. Thermo-responsive poly(2-(2-methoxyethoxy)ethyl methacrylate) (poly(MEO2MA)) hydrogel fabricated with different amounts of di(ethylene glycol) dimethacrylate (DEGDMA) cross-linker was characterised using texture profile analysis. More cross-linking sites incorporated within the hydrogel limit the swelling ability where 1.0 and 10?mol-% of DEGDMA swell by 8.03 and 1.92 times, at 5°C. Hydrogel textural and tensile property correlated with the cross-linker amount. Meanwhile, network structure disentanglement within swollen hydrogel reduced the force required for deformation. Thus, the swelling behaviour, textural and tensile properties were investigated to discern the possible biomedical applications suitable for this hydrogel.

Rice straw cellulose a biomass materials, naturally found in abundance. It is low cost, eco-friendly and biodegradable. Alpha cellulose is prepared from rice straw using chemical method namely acid hydrolysis and alkaline treatment. Both of the samples treatments were bleached using sodium chlorite (NaClO2). Alkaline treatment shows higher in producing alpha cellulose, 20.68% rather than 12.20% by acid hydrolysis.

Cellulose Micro/Nano fibers (CMNF) from various plants which is Resak (Vatica spp.) waste, Merbau (Intsia bijuga) waste, banana (Musa acuminata) pseudo-stem and pineapple (Ananas comosus) leaf fibers have been isolated and characterized. Isolation of microfibril cellulose from raw fibers was achieved using alkaline treatment and bleaching. The treated and untreated samples were characterized using x-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). Characterizations of treated and untreated samples were compared. The comparison between those treated and untreated samples giving different crystallite size, crystallinity, arrangement of CMNF and surface morphology from different plants. Hence, with these information different nanocomposite from CMNF can be constructed and manipulated for various application.

Rice husk ash (RHA) is a product from the burning of the rice husk and it become a significant material for glass preparation due to high amount of amorphous silica that can be produced. From the recent studies, the highest amount of silica is observed at 550°C at 6 hours which is 99.36% by XRF detection. Nevertheless, the amount of silica decreasing proportionally if the temperature profile is higher than 550°C and the time taken is more than 6 hours. Quaternary glasses are prepared using melt-quenching method using the highest amount of silica from RHA combined with Bismuth Oxide (Bi2O3), Boron Oxide (B2O3), and Zinc Oxide (ZnO). The ratio of quaternary glass that used are 30%SiO2: 20%B2O3: xZnO : (50-x)%Bi2O3 (% mole) ; where x= 10,20,30,40. The physical properties and glass transition temperature (Tg) profiles are determined using standard measurement instrument. Moreover, the density measured will enhance the verification of Oxygen Packing Density for prepared quaternary glasses.

Cellulosic materials derived from pineapple leaves fibers (PALF) which are being wasted after fruit harvested. There are two methods to extract cellulose from PALF. First methods were using sodium hydroxide (NaOH) 2% for alkaline treatment and bleached by sodium hypochlorite (NaClO) and buffer. Second method, cellulose was extracted using peroxyacetic acid delignification and bleached the sample in acidified pH 3 hydrogen peroxide solution. From X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) data’s, it is proven that both samples of cellulose have shown cellulose I structure.

Cellulose is one of the most abundant biomass material in nature extracted from natural fibers. Its hierarchical structure allows different kinds of microfibril cellulosic fillers to be obtained known as cellulose microfibril or microfibrillated cellulose (MFC). MFC is generally prepared by either acid hydrolysis, or chemical treatments, or by a high pressure refiner. In this study, attempts have been made to extract MFC from Resak’s hardwood waste (Vatica spp.) at atmospheric pressure using single-stage peroxyacetic acid delignification and Totally Chlorine-Free bleaching methods. The morphology structure of samples were characterized using Field emission scanning electron microscope (FESEM) and X-ray diffraction (XRD).

Cellulosic material derived from Merbau (Intsia bijuga) was extracted at atmospheric pressure. In the initial stage the sample was delignified using peroxyacetic acid to remove the amorphous. In the second stage the samples were double bleached using hydrogen peroxide (H2O2) and sodium Hydroxide (NaOH). From the X-Ray Diffraction (XRD) data it is evident that both acid and alkali bleached celluloses have rich cellulose I structure. The results are supported by FTIR study in which all samples shown typical spectra of cellulose.

Hardwood is wood from angiosperm trees. The characteristic of hardwood include flowers, endosperm within seeds and the production of fruits that contain the seeds. This paper aims to discuss the preparation and characterization of cellulose obtained from hardwood. The hardwood Merbau (Intsia bijuga) was chosen as raw material in this study. Alkaline treatment and delignification methods were used for the preparation of cellulose. Acid hydrolysis was employed to produce cellulose nanocrystal (CNC). The treated and untreated samples were characterized using x-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). The final product, from both trated and untreated samples were then compared.

Water pollution due to heavy metal contamination has become a critical environmental issue. Thus, effective treatment for polluted water, such as simple adsorption to remove heavy metals, is gaining importance. Towards this end, zeolitic imidazolate framework-L (ZIF-L) with graphene oxide (GO) was successfully incorporated in the synthesis of novel ZIF-L/GO 20 and ZIF-L/GO 50 adsorbents using 20% and 50% loading percentages of GO, respectively, with ultrapure water as the solvent. The morphologies of ZIF-L changed to a flower-like structure with the introduction of 20% GO and turned into smaller irregular shapes when 50% GO was added. These novel adsorbents have demonstrated high adsorption capacities for Cd(II) adsorption at 172.42 mg/g (ZIF-L/GO 20) and 188.68 mg/g (ZIF-L/GO 50), with the optimum dosage of 0.2 g/L of adsorbents. The adsorption isotherms fit Langmuir isotherm, which suggested that adsorption occurred through uniform and monolayer sorption on the surface sites. The electrostatic attraction between the cationic Cd(II) and negatively charged surface played a crucial role as the main pathway in Cd(II) adsorption. Based on the investigated kinetic models, Cd(II) adsorption had a better correlation with the pseudo-second-order kinetic model, which showed that chemisorption occurred during the Cd(II) removal process. The findings of this study revealed that ZIF-L/GO has the potential of becoming the perfect adsorbent for cadmium removal from aqueous solutions.

Gold nanorods (GNRs) have a unique optical property of metallic nanoparticles due to the localised surface plasmon resonance (LSPR) effect, which depends on the size, shape and dielectric property of the surrounding medium. Anisotropic GNRs optical behaviours are approximated based on Mie-Gans theory by predicting the presence of dual absorption bands, which are the transverse and longitudinal bands. This study discussed the investigation of the GNRs formation by controlling three process parameters; centrifugation speed, seed solution concentration and growth solution ageing period to overcome the limitations of rod-shaped nanoparticles due to inhomogeneity, uncontrollable shape and aspect ratio. Bottom-up synthesis has been used to produce fine-tuning gold nanostructures. High yield and aspect ratio of GNRs are achieved at 20 h with 10 μl seed solution concentration and 5000 rpm centrifugation speed for particles separation; a longer growth ageing period caused the uncontrollable formation of GNRs with stacking nanoparticles. Therefore, the optimized GNRs with an aspect ratio of 4.23 ± 0.36 and the yields 74.81% are used as sensing material to detect the targeted herbicide analyte, namely triclopyr butotyl. The concentration of triclopyr butotyl can be detected as low as 3% ~ 1.03 mg/l using the sensing mechanism that was based on the plasmonic effect; which was resulting from the collective oscillations of conduction band electrons in a rod nanoparticle.

Quaternary glasses were successfully fabricated using melt quenching technique based on the chemical compound composition (x)Bi2O3–(0.5−x) ZnO–(0.2)B2O3–(0.3)SiO2, where (x=0.1, 0.2, 0.3, 0.4, 0.45) mole. The sources of SiO2was produced from rice husk ash (RHA) at 99.36% of SiO2. The Urbach energy was increased from 0.16eV to the 0.29eV as the mole of Bi2O3increased in the glass structure. The indirect energy band gap is indicated in decrement pattern with 3.15eV towards 2.51eV. The results of Urbach energy and band gap energy that were obtained are due to the increment of Bi3+ion in the glass network. The refractive indexes for the prepared glasses were evaluated at 2.36 to 2.54 based on the Lorentz–Lorentz formulation which correlated to the energy band gap. The calculated of molar polarizability, electronic polarizability and optical basicity exemplify fine complement to the Bi2O3addition in the glass network. The glass sample was indicated in amorphous state.

We investigated inverted bulk heterojunction solar cells fabricated with gold (Au) leaf as laminated top electrodes. We demonstrate that the Au leaf can be successfully transferred from a supporting poly(ethylene terephthalate) (PET) substrate to the surface of poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT:PSS) because PEDOT:PSS has a sufficiently higher work of adhesion than PET. Under optimized lamination conditions, the contact between the Au leaf and the PEDOT:PSS becomes homogeneous, and the power conversion efficiency (PCE) improves. When a naphtho[1,2-c:5,6-c']bis[1,2,5]thiadiazole-based polymer is used as the p-type semiconductor, the PCE reaches 5.07%. The laminated devices exhibit excellent stability comparable to that of evaporated devices.