Using irradiated doped-silica preforms from which fibres for thermoluminescence dosimetry applications can be fabricated we have carried out a range of luminescence studies, the TL yield of the fibre systems offering many advantages over conventional passive dosimetry types. In this paper we investigate such media, showing emission spectra for irradiated preforms and the TL response of glass beads following irradiation to an 241Am-Be neutron source located in a tank of water, the glass fibres and beads offering the advantage of being able to be placed directly into liquid. The outcomes from these and other lines of research are intended to inform development of doped silica radiation dosimeters of versatile utility, extending from environmental evaluations through to clinical and industrial applications.
Pontamine fast scarlet 4B is a red paper and textiles dye that has recently been introduced as a fluorescent probe for plant cell walls. Pontamine exhibits bifluorescence, or fluorescence dependent on the polarization of the excitation light: Because cellulose is aligned within the cell wall, pontamine-labelled cell walls exhibit variable fluorescence as the excitation polarization is modulated. Thus, bifluorescence measurements require polarized excitation that can be directly or indirectly modulated. In our confocal microscopy observations of various cellulose samples labelled with pontamine, we modulated excitation polarization either through sample rotation or by the confocal's scanfield rotation function. This variably rotated laser polarizations on Leica confocal microscopes, but not those from other makers. Beginning with samples with directly observable microfibril orientations, such as purified bacterial cellulose, the velamen of orchid roots and the inner S2 layer of radiata pine compression wood, we demonstrate that modelling the variations in pontamine fluorescence with a sine curve can be used to measure the known microfibril angles. We then measured average local microfibril angles in radiata pine samples, and showed similar microfibril angles in compression and normal (opposite) wood. Significantly, bifluorescence measurements might also be used to understand the degree of local cellulose alignment within the cell wall, as opposed to variations in the overall cellulose angle.
This paper aim is to design an education kit for wastewater system that can maintain
the standard parameters of neutralized wastewater by maintaining the suitable pH
(Potential Hydronium) level and temperature of the wastewater from industry by using
fuzzy controller. This study is capable to control the unwanted bacteria by automatic
regulatory and monitoring the temperature, pH and water level. Fuzzy logic method is
use to control and monitor pH level as well as the temperature during clarifying process
because pH control process is a complex physical-chemistry process of strong
individuality of time-varying and non-linearity properties. Pumps used in the prototype
need to be controlled precisely to enable either acid or base to be pumped into mix
tank of the wastewater treatment. The control and monitoring system, which has been
designed through LabVIEW front panel will ease end user in inspection of the
parameters involve in wastewater treatment. The entire system output could be
observed remotely in Data Dashboard application in smartphone or tablet. The GUI
was designed and interfaced with the prototype constructed to carry out the process
of controlling and monitoring the required parameters. Few tests were conducted
repetitively to analyse the performance of the system parameters. It was found that
the controlled set point fixed within the range of pH 7.6-8.4, temperature 25-29.44
Celsius and water level of 20cm in this research that was effectively achieved in the
entire test conducted. In addition, the wastewater system accuracy and performance
is 96.72% and 90.22% respectively.
The importance of the performance of concrete cannot be neglected since it is the early indicator of its physical and mechanical properties. It became more important when material with different physical properties than normal material such as rubber tire was used as concrete constituent. This paper presented apart of research result conducted on mortar and concrete with crumb rubber. Crumb rubber was replaced at 10%, 15% and 20% as sand replacement by volume. In addition, ordinary Portland cement was added to silica fume at 10% and 15% by weight. The properties measured in this study are air content and workability test. As for workability, superplasticizers were constantly used at 1% dosage for all mortar mixture, and 0.5% to 0.7% for concrete mixture. The air content was set at 4% to 6% and mortar flow test was conducted on a steel plate, shocked 15 times in 15 seconds and concrete slump test was carried out using slump cone equipment. Pressure method was used to measure air content. All mixes were done in a controlled room temperature. Results showed that when CR was added in the mixture segregation was observed in mortar requiring a high dose of superplasticizer to be added to improve the workability while air-modifying agent was used to reduce the mortar air content. In concrete mixture, low dosage of superplasticizers was required for workability and air-entrained agent was injected into the mixture to increase the air content between 4%-6%.
The aim of this paper is to augment the existing literature on convergence of CO2 emissions, by adding carbon footprint per capita and ecological footprint per capita to the convergence debate. We use the residual augmented least squares regression to examine the stochastic convergence of the environmental indices in 27 OECD countries. Furthermore, in contrast to the previous studies which mainly used the conventional beta-convergence approach to examine conditional convergence, we use a beta-convergence method that is capable of identifying the actual number of countries that contribute to conditional convergence. The sigma-convergence of the environmental indices is also examined. The results suggest that conditional convergence exists in 12 countries for CO2 emissions per capita, 15 countries for carbon footprint per capita and also 13 countries for ecological footprint per capita. There is evidence for sigma-convergence for all the three indicators. The policy implications of the results are discussed in the body of the paper.
The main goal of this paper was to study the effect of ultrasonic treatment time on the mechanical properties of thermoplastic natural rubber(TPNR) reinforced with hybrid MWNTs-OMMT. The intercalation of TPNR enhancement into layers of clay by increasing the d-spacing was found using X-ray diffraction. The tensile properties of nanocomposites treated with ultrasonic increased when compared with untreated nanocomposites. The optimum ultrasonic treatment time was obtained at 3 h. The transmission electron microscope micrograph showed a combination of intercalated-exfoliated structure of the TPNR composites with organic clay and dispersion of MWNTs. The ultrasonic treatment can promote the dispersion of MWNTs-OMMT in TPNR and also improved the compatibility of hybrid filler and the TPNR matrix.
In this paper, the synthesis and characterisation of caffeine-imprinted polymers are described. The polymers were prepared in monolithic form via both reversible addition-fragmentation chain-transfer (RAFT) polymerisation and conventional free radical polymerisation, using methacrylic acid and ethylene glycol dimethacrylate as the functional monomer and crosslinking agent, respectively. The potential benefits in applying RAFT polymerisation techniques towards the synthesis of molecularly imprinted polymers (MIPs) are explored and elucidated. The pore structures of the polymers produced were characterised by nitrogen sorption porosimetry and the molecular recognition properties of representative products were evaluated in high-performance liquid chromatography (HPLC) mode. Molecular imprinting effects were confirmed by analysing the relative retentions of analytes on imprinted and non-imprinted HPLC
stationary phases. It was found that a caffeine-imprinted polymer synthesised by RAFT polymerisation was superior to a polymer prepared using a conventional synthetic approach; the imprinting factor and column efficiency were found to be higher for the former material.
This paper is focussed on conductivity and dielectric properties of Poly (vinyl) chloride (Pvc)- ammonium triflate (NH4CF3SO3) - butyltrimethyl ammonium bis (trifluoromethyl sulfonyl) imide (Bu3MeNTf2N) ionic liquid, electrolyte system. The electrolyte is prepared by solution cast technique. In this work, the sample containing 30 wt. % NH4CF3SO3 exhibits the highest room temperature conductivity of 2.50 x 10-7 S cm' . Ionic liquid is added in various quantities to the 70 wt. % Pvc-30 wt. % NH4CF3SO3 composition in order to enhance the conductivity of the sample. The highest conductivity at room temperature is obtained for the sample containing 15 wt. % Bu3MeNTf2N with a value of 1.56 x 10 -4 S cm' . The effects of ionic liquid addition on the frequency dependent dielectric properties of PVC based electrolytes is investigated by electrochemical impedance spectroscopy (Eis) at room temperature. The values of dielectric constant were found to increase with increasing conductivity of the samples. Analysis of the ac conductivity data showed the electrolytes to be of the non-Debye type.
The paper making industry is characterized by high rate of water consumption and hence high rate of wastewater generation. The purpose of this research was to assess and optimize the existing complete mix activate sludge treatment plant that is used to treat the high strength paper mill effluent with the highest possible efficiency at a reasonable cost. The collected paper mill wastewater is equalized in an equalization tank before being pumped to the treatment plant. The treatment plant includes chemical treatment unit, complete mix activated sludge and granular media filtration unit. The results showed that effluent of a chemical treatment unit was found to be relatively similar to the laboratory simulated plain sedimentation unit. It can be concluded that addition of chemical coagulant can be eliminated with an overall saving of chemical addition costs. The complete mixing activated sludge achieved good removal of biochemical oxygen demand (BOD) and chemical oxygen demand (COD). Furthermore, the results showed that the plant is operated under low BOD:P ratio. The treatment efficiency of the plant can be improved by increasing the phosphorous dose to the plant to have BOD:P ratio of 100:0.5 to 100:1. It was found that 50% of the treated effluent is recycled to the manufacturing process, however this percentage can be increased through proper plant optimization and control of nutrient addition to the activated sludge unit.
Various production methods have been developed for graphene production, but each of them falls short in either the economic or quality aspect. In this paper, we present the flame deposition method, a modified chemical vapor deposition (CVD) that uses an open-flame. In this method, resulting carbon deposits were found to be graphitic in nature, thereby suggesting multilayer graphene growth in a very short reaction time of 5 min. Furthermore, the deposits were transferred onto a cyanoacrylate plastic substrate and its sheet resistance was measured to be 81 ohm/square. The results showed that open-flame deposition exhibits high potential for low-cost, low-energy and high-quality production of graphene.
Disease frequency is used to measure the situation of the disease with reference to the population size and time period
which is in a fractional form. The lower part of the fraction, known as denominator is the important part as it was used
to calculate a rate or ratio. Since the disease frequency is based on a ratio estimator, the results are highly dependent
upon the value of denominator. Therefore, the main aim of this paper was to propose a new method in calculating the
denominator for the relative risk equation with the application to chikungunya disease data from Malaysia. The new
method of calculating the denominator of the relative risk equation includes the use of discrete time-space stochastic
SIR-SI (susceptible-infective-recovered for human population and susceptible-infective for vector population) disease
transmission model instead of the total disease counts. The results of the analysis showed that the estimation of expected
disease counts based on total posterior means can overcome the problem of expected counts estimation based on the total
number of disease especially when there is no observed disease count in certain regions. The proposed new approach to
calculate the denominator for the relative risk equation is suitable for the case of rare disease in which it offers a better
method of expected disease counts estimation.
In this paper, a support vector regression (SVR) using radial basis function (RBF) kernel is proposed using an integrated
parallel linear-and-nonlinear model framework for empirical modeling of nonlinear chemical process systems. Utilizing
linear orthonormal basis filters (OBF) model to represent the linear structure, the developed empirical parallel model
is tested for its performance under open-loop conditions in a nonlinear continuous stirred-tank reactor simulation case
study as well as a highly nonlinear cascaded tank benchmark system. A comparative study between SVR and the parallel
OBF-SVR models is then investigated. The results showed that the proposed parallel OBF-SVR model retained the same
modelling efficiency as that of the SVR, whilst enhancing the generalization properties to out-of-sample data.
This paper studies about water obtained from fish pond of fisheries research centre. Usual water
quality parameters such as pH, COD, Turbidity and Ammonia content were analyzed before and
after irradiation. Electron beam irradiation was used to irradiate the water with the dose 100 kGy,
200 kGy and 300 kGy. Only high dose was applied on this water as only a limited amount of
samples was supplied. All the parameters indicated a slight increase after irradiation except for the
ammonia content, which showed a gradual decrease as irradiation dose increases. Sample
condition was changed before irradiation in order to obtain more effective results in the following
batch. The water sample from fisheries was diluted with distilled water to the ratio of 1:1.This was
followed with irradiation at 100 kGy, 200 kGy and 300 kGy. The results still showed an increase in
all parameters after irradiation except for ammonia content. For the following irradiation batch,
the pH of the sample was adjusted to pH 4 and pH 8 before irradiation. For this sample the
irradiation dose selected was only 100 kGy. A higher value of ammonia was observed for the
sample with pH 4 after irradiation. Other parameters were almost the same as the first two batches
Recycled paper mill effluent (RPME) contains high levels of organic and solid compounds, causing operational problems for anaerobic biological treatment. In this study, a unique modified anaerobic inclining-baffled reactor (MAI-BR) has been developed to treat RPME at various initial chemical oxygen demand (COD) concentrations (1000-4000 mg/L) and hydraulic retention times (HRTs) (3 and 1 day). The COD removal efficiency was decreased from 96 to 83% when the organic loading rate (OLR) was increased from 0.33 to 4 g/L day. Throughout the study, a maximum methane yield of 0.25 L CH4/g COD was obtained, while the pH fluctuated in the range of 5.8 to 7.8. The reactor performance was influenced by the development and distribution of the microbial communities. Based on the next-generation sequencing (NGS) analysis, the microbial community represented a variety of bacterial phyla with significant homology to Euryarchaeota (43.06%), Planctomycetes (24.68%), Proteobacteria (21.58%), Acidobacteria (4.12%), Chloroflexi (3.14%), Firmicutes (1.12%), Bacteroidetes (1.02%), and others (1.28%). The NGS analysis showed that the microbial community was dominated by Methanosaeta concilii and Candidatus Kuenenia stuttgartiensis. This can be supported by the presence of filamentous and spherical microbes of different sizes. Additionally, methanogenic and anaerobic ammonium oxidation (ANAMMOX) microorganisms coexisted in all compartments, and these contributed to the overall degradation of substances in the RPME. Graphical abstract ᅟ.
This paper reports the mechanical properties of cement composite boards made using wood-wool from a lesser known Malaysian timber species. A total of 108 specimens were fabricated using Portland cement (Type I) and wood-wool from Kelampayan (Neolamarckia cadamba). The cement to wood ratio of the specimens was 2 to 1 by weight. The aim of the study was to determine the density; flexural, compressive and tensile strength of wood-wool cement composite boards (WWCCB) by studying boards with wood-wool sized 1.5 mm, 2.5 mm and 3.5 mm and board thickness 25 mm, 50 mm and 75mm. The physical and mechanical properties of the boards were evaluated according to ASTM D 1037-96a (Standard testing method for evaluating properties of wood-based fibre and particle panel materials) and MS934:1986. Results showed that mechanical properties of WWCCB were greatly influenced by the density; as the density decreased, the mechanical strengths also decreased. However, the strength properties of the composite boards did not display a similar trend when subjected to different types of loading conditions. The compressive strength increased with thicker boards (50 mm and 75 mm) but the modulus of elasticity and modulus of rupture declined as the thickness of the board was increased.
A study on the effects of alkali treatment and compatibilising agent on the tensile properties of pineappleleaf fibre (PALF) reinforced high impact polystyrene (HIPS) composite is presented in this paper. Thetensile properties of natural fibre reinforced polymer composites are mainly influenced by the interfacialadhesion between the matrix and the fibres. In this study, several chemical modifications were employedto improve the interfacial matrix-fibre bonding and this resulted in the enhancement of tensile propertiesof the composites. In this study, the surface modification of pineapple fibre with alkali treatments andcompatibilizer were used to improve the adhesion between hydrophilic pineapple fibre and hydrophobicpolymer matrix. There are two concentrations of NaOH treatments and compatibilizer used in this study,namely, 2 and 4 wt. %. The results show that the alkali treated fibre and the addition of compatibilisingagent in PALF/HIPS composites have improved the tensile strength and tensile modulus of the composites.
This paper studied the thermal behaviour of pineapple leaf fibre (PALF) reinforced high impact polystyrene (HIPS) composite. Thermogravimetric analysis (TGA) and differential scanning calorimetric (DSC) analysis were used to measure the thermal characteristic of HIPS/PALF composites. In particular, the TGA analysis was utilized to measure the degradation and decomposition of materials in neat polystyrene, pineapple fibre, and the composites. The measurements were carried out in the temperature of 25°C – 800°C, at a heating rate of 20°C min-1 and the nitrogen gas flow was 50 mL min-1. The temperature of the DSC analysis was programmed to be between 25°C – 300°C. The results from TGA analysis show that the addition of pineapple fibre has improved the thermal stability of the composites as compared to neat HIPS. In addition, the effects of compatibilising agent and surface modification of PALF with alkali treated were also determined and compared.
The performance and operational characteristics of a laboratory scale modified anaerobic hybrid baffled (MAHB) reactor were studied using recycled paper mill effluent (RPME) wastewater. MAHB reactor was continuously operated at 35°C for 90 days with organic loading rate (OLR) increased from 0.14 to 0.57 g/L/dy. This present study demonstrated that the system was proficient in treating low strength RPME wastewater. Highest carbon oxygen demand (COD) removal were recorded up to 97% for an organic loading of 0.57 g /L/dy while effluent alkalinity assured that the system pH in the MAHB compartments were of great advantages to acidogens and methanogens respectively. Methane and biogas production rate shows increment as the load increases, which evidently indicated that the most significant approach to enhance gas production rates involves the increment of incoming substrate moderately. Variations of biogas and volatile fatty acid (VFA) in different compartments of MAHB reactor indicated the chronological degradation of substrate. The compartmental structure of MAHB reactor provided its strong ability to resist shock loads. From this present study, it shows the potential usage of MAHB reactor broadens the usage of multi-phase anaerobic technology for industrial wastewater treatment.
The temperature profile of a cryogenic system for cooling of beryllium filter of a small-angle neutron scattering (SANS) instrument of TRIGA MARK II PUSPATI research reactor was investigated using computational fluid dynamics (CFD) modeling and simulation. The efficient cooling of beryllium filter is important for obtaining higher cold neutron transmission for the SANS instrument. This paper presents the transient CFD results of temperature distributions via the thermal link to the beryllium and simulation of heat
flux. The temperature simulation data are also compared with the experimental results for the cooling time and distribution to the beryllium.
Boundary element method (BEM) is a numerical technique that used for modeling infinite domain as is the case for galvanic corrosion analysis. The use of boundary element analysis system (BEASY) has allowed cathodic protection (CP) interference to be assessed in terms of the normal current density, which is directly proportional to the corrosion rate. This paper was present the analysis of the galvanic corrosion between Aluminium and Carbon Steel in natural sea water. The result of experimental was validated with computer simulation like BEASY program. Finally, it can conclude that the BEASY software is a very helpful tool for
future planning before installing any structure, where it gives the possible CP interference on any nearby unprotected metallic structure.