This paper examines the temperature profile of a building material and also a
built space. The study directly examines the influence of solar radiation on
building material and the heat it generated and diffuses into the built space.
Two experiments are presented. The first look at a simple technique for
evaluating heat performance of a building material, and the second evaluates
the performance of a cross-ventilated built space with respect to solar radiation.
Leachate (liquid pollutant), which is highly contaminated with organic matter and toxic substances is a major
problem that arised from landfill. Biological methods have proven to be effective to remove organic matters that are
abundant in leachate. This study is intended to compare the used of free mycelia and immobilized mycelia of the
white-rot fungi, Ganoderma australe for the removal of landfill leachate organics. The organics fraction of landfill
leachate was measured by biological oxygen demand (BOD5), and chemical oxygen demand (COD). The experiment
revealed that free mycelia of G. australe showed capability in removing leachate BOD5 but not COD. However, the
use of immobilized G. australe displayed the best result in the removal of BOD5 and COD leachate after 4 weeks of
treatment in flasks with 93.09% and 17.84% percentage removal of BOD5 and COD, respectively. Therefore, G.
australe can be considered potentially useful in the treatment of landfill leachate as they can help in removing BOD
and COD due to their biodegradative abilities.
Polymerase Chain Reaction (PCR) analysis in the study of oil palm DNA generally carried out by using DNA template obtained from grinding of leaf samples in liquid nitrogen followed by hexadecyltrimethylammonium bromide (CTAB) protocol. The present study explores the FTA card as a method to retrieve PCR-amplifiable oil palm DNA. Oil palm leaves were cut and crushed before deposited onto the FTA card. An attempt was made by amplifying the EgSHP gene using a punch of FTA card as a DNA template. The successful outcome of PCR was measured by the presence of PCR amplicons on 1% agarose gel electrophoresis, indicate the genotype of oil palm fruit form. This present study demonstrates that the FTA card provides a versatile alternative to the study of oil palm genetics.
Elaeis oleifera serves as a source of genetic foundation in oil palm improvement programme, as it possess several interesting agronomic traits such as slow growth, higher oil unsaturation and disease resistance. Malaysian Palm Oil Board (MPOB) has developed a collection of simple sequence repeats (SSRs) from Elaeis oleifera genome (E. oleifera-gSSRs). A total of 21 polymoprhic SSR markers were evaluated in the attempt to assess the population structure of E. oleifera populations. The appropriate common ancestry (K) value was determined to be seven from the likelihood scores. The profile from STRUCTURE analysis indicates considerable sharing of genetic components among E. oleifera population with an exception for Population 01 from Columbia and Population 02 from Costa Rica. The present study provides information on population structure of MPOB E. oleifera collection via model-based method for germplasm conservation and utilisation in breeding programmes.
Clustering in Wireless Sensor Network (WSN) is one of the methods to minimize the energy usage of
sensor network. The design of sensor network itself can prolong the lifetime of network. Cluster head in
each cluster is an important part in clustering to ensure the lifetime of each sensor node can be preserved
as it acts as an intermediary node between the other sensors. Sensor nodes have the limitation of its
battery where the battery is impossible to be replaced once it has been deployed. Thus, this paper
presents an improvement of clustering algorithm for two-tier network as we named it as Multi-Tier
Algorithm (MAP). For the cluster head selection, fuzzy logic approach has been used which it can
minimize the energy usage of sensor nodes hence maximize the network lifetime. MAP clustering
approach used in this paper covers the average of 100Mx100M network and involves three parameters
that worked together in order to select the cluster head which are residual energy, communication cost
and centrality. It is concluded that, MAP dominant the lifetime of WSN compared to LEACH and SEP
protocols. For the future work, the stability of this algorithm can be verified in detailed via different data
and energy.
Natural fiber is incompatible with hydrophobic polymer due to its hydrophilic nature. Therefore, surface modification of fiber is needed to impart compatibility. In this work,superheated steam (SHS)-alkali was introduced as novel surface treatment method to modify oil palm mesocarp fiber (OPMF) for fabrication of biocomposites. The OPMF was first pre-treated with SHS and subsequently treated with varying NaOH concentration (1, 2, 3, 4 and 5%) and soaking time (1, 2, 3 and 4h) at room temperature. The biocomposites were then fabricated by melt blending of 70 wt% SHS-alkali treated-OPMFs and 30 wt% poly(butylene succinate) in a Brabender internal mixer followed by hot-pressed moulding. The combination treatment resulted in fiber with rough surface as well as led to the exposure ofmicrofibers. The tensile test result showed that fiber treated at 2% NaOH solution and 3h soaking time produced biocomposite with highest improvement in tensile strength (69%) and elongation at break (36%) in comparison to that of untreated OPMF. The scanning electron micrographs of tensile fracture surfaces of biocomposite provide evident for improved adhesion between fiber and polymer after thetreatments.This work demonstrated that combination treatments of SHS and NaOH could be a promising way to modify OPMF for fabrication of biocomposite.
In recent years, the utility grid system is more essential for the power
transmission and distribution system because it cannot produce harmful
gases or no discharge waste in the environment. PWM based phase
synchronous invert systems are generally utilised in the high efficiency
energy supply, long distance and higher power quality. The inverter output
voltage depends on the coupling transformer, input sources and invert
controllers. An inverter using a three leg IGBT has been designed for utility
grid and simulated by using MATLAB2014a. In this paper, both sides of
the LCL filters are used for removing the DC ripple current, reducing the
noise and synchronous the output phase between inverter and the utility
grid. The PWM controller has created pulse signal to control the inverter,
electronic switches and precisely synchronise with grid line frequency. In
this system, the input DC voltage 500V, switching frequency 1.65 kHz, grid
frequency 50Hz, 20 km feeder (resistance, inductance and capacitance per
unit length, which are 0.1153, 1.05e-3 and 11.33e-09 ohms/km) with 30MW
three phase load (active and inductive reactive power which are 30e6 W
and 2e6 var) and also a balanced utility grid load of star configuration (00,
1200, and 2400 degree) are considered in the design. On the other hand,
three phase transformer consists of three signal phase transformers, normal
power 100e3, magnetization resistance and inductance which are 500 pu and
416.67pu are considered in this design. The system conversion efficiency
is 99.94% and 99.96%, while the total THD are 0.06% on inverter side
and 0.04% on grid side.
Molecular self-assembly is ubiquitous in nature and has emerged as a new approach to produce new materials in chemistry, engineering, nanotechnology, polymer science and materials. Molecular self-assembly has been attracting increasing interest from the scientific community in recent years due to its importance in understanding biology and a variety of diseases at the molecular level. In the last few years, considerable advances have been made in the use of peptides as building blocks to produce biological materials for wide range of applications, including fabricating novel supra-molecular structures and scaffolding for tissue repair. The study of biological self-assembly systems represents a significant advancement in molecular engineering and is a rapidly growing scientific and engineering field that crosses the boundaries of existing disciplines. Many self-assembling systems are range from bi- and tri-block copolymers to DNA structures as well as simple and complex proteins and peptides. The ultimate goal is to harness molecular self-assembly such that design and control of bottom-up processes is achieved thereby enabling exploitation of structures developed at the meso- and macro-scopic scale for the purposes of life and non-life science applications. Such aspirations can be achieved through understanding the fundamental principles behind the selforganisation and self-synthesis processes exhibited by biological systems.
To ascertain the level of knowledge among primary school teachers towards the management of traumatic dental injuries (TDIs) in school and to determine the preference among teachers regarding the education tools that can be used to increase awareness and knowledge among them. A total of 150 teachers from primary schools in three different districts were included in the study and they were given self-administered questionnaires to be filled. The validated questionnaire was distributed randomly in the selected schools. The questionnaire included two scenarios comprising of tooth fracture and avulsion. Questions regarding awareness and management of these scenarios were asked. All 150 participants answered the questionnaire; of these 74% were females 26% were males. 64% of the participants had received tertiary education. Although 70% of teachers had obtained first aid training, only 9.3% of them had received training regrading dental injuries. About 53% of participants knew the correct answer for the appropriate response to fractured tooth and only 35.3% managed to correctly answer the question related to appropriate response to an avulsed tooth. Only 38.7% knew about appropriate rinsing solution and a mere 4.7% were familiar with proper storage media. Even though the teachers have poor knowledge regarding management of dental injuries, it is reassuring to know that 93% of them are keen on further training and awareness. More educational programmes need to be introduced to empower the teachers with the relevant knowledge required to deal with dental emergencies.
Accurate inspection of welded materials is important in relation to achieve acceptable standards. Radiography, a non-destructive test method, is commonly used to evaluate the internal condition of a material with respect to defect detection. The presence of noise in low resolution of radiographic images significantly complicates analysis; therefore attaining higher quality radiographic images makes defect detection more readily achievable. This paper presents a study pertaining to the quality enhancement of radiographic images with respect to different types of defects. A series of digital radiographic weld flaw images were smoothed using multiple smoothing techniques to remove inherent noise followed by top and bottom hat morphological transformations. Image quality was evaluated quantitatively with respect to SNR, PSNR and MAE. The results indicate that smoothing enhances the quality of radiographic images, thereby promoting defect detection with the respect to original radiographic images.
Pure TiO2 and Cr doped TiO2 (0.1-1.0wt% Cr) nanoparticles were synthesized via sol gel method. This
study focusing on narrowing the TiO2 band gap energies in order to enhance the photocatalytic efficiency
under visible light. The synthesized samples were characterized by X-Ray diffraction method (XRD), field
emmision (FESEM) and also UV-Vis diffuse reflectance spectroscopy (DRS).The photocatalytic activity
under sunlight irradiation was demonstrated by photocatalytic decomposition of methylene blue in water
using UV/Vis spectrophotometer. The XRD analysis of pure TiO2 and doped TiO2 calcined at 500oC
showed a mixture of anatase and rutile phases with decreasing crystallites size from 13.3 nm to 11.6 nm
as the concentration of Cr was increased. The anatase-rutile phase transformation increased from 28.8%
to 57.4%. An indication shows that at 0.75wt% Cr the anatase and rutile phases have equal composition
percentage. This study demonstrated that band gap energy of TiO2 was reduced with Cr doping which
could enhance the photocatalytic efficiency. Sample containing 1.0wt% exhibit the lowest optical band
gap energy at 2.86 eV. The optimum chromium doping concentration was found to be at 0.1 wt% Cr
corresponding to band gap energy of 2.87 eV and degradation rate of 84%.
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.
A good quality of rainfall data is highly necessary in hydrological and meteorological analyses. Lack
of quality in rainfall data will influence the process of analyses and subsequently, produce misleading
results. Thus, this study is aimed to propose modified missing rainfall data treatment methods that
produced more accurate estimation results. In this study, the old normal ratio method and the
modified normal ratio based on trimmed mean are combined with geographical coordinate method.
The performances of these modified methods were tested on various levels of the missing data of 36
years complete daily rainfall records from eighteen meteorology stations in Peninsular Malaysia. The
results indicated that both modified methods improved the estimation of missing rainfall values at the
target station based on the least error measurements. Modified normal ratio based on trimmed mean
with geographical coordinate method is found to be the most appropriate method for station Batu
Kurau and Sg. Bernam while modified old normal ratio with geographical coordinate is the most
accurate in estimating the missing data at station Genting Klang.
In this study, extracted plumeria and celosia cristata flowers have been used as the sensitizer for dyesensitized
solar cells (DSSC). The cells were fabricated using TiO2 as a semiconductor layer
deposited on transparent Indium doped tin oxide (ITO) conductive glass using a spin coating
technique. The films with dyes were characterized by UV-VIS absorption spectra. The photovoltaic
properties of DSSC were studied under an incident irradiation of 100 mW/cm2
. The I-V characteristic
curves of all fabricated cells were measured and analysed. The energy conversion efficiency (η) of the
cells consisting of plumeria extract and celosia cristata extract was 3.73 × 10-6
and 1.18 × 10-7 respectively.
Anthropogenic CO2 emissions has led to global climate change and widely contributed to global
warming since its concentration has been increasing over time. It has attracted vast attention
worldwide. Currently, the different CO2 capture technologies available include absorption, solid
adsorption and membrane separation. Chemical absorption technology is regarded as the most
mature technology and is commercially used in the industry. However, the key challenge is to
find the most efficient solvent in capturing CO2. This paper reviews several types of CO2 capture
technologies and the various factors influencing the CO2 absorption process, resulting in the
development of a novel solvent for CO2 capture.
A polystyrene (PS)-anchored Pd(II) metal complex was synthesized on cross-linked polymer by heating a mixture of chlorometylated polystyrene with phenyldithiocarbazate and carbon disulfide in the presence of potassium hydroxide (KOH) in dimethylformamide (DMF). The reaction mixture was heated at 80 °C to form the corresponding phenyldithiocarbazate-functionalized polymer. Then, it was treated with bis(benzonitrile)palladium(II) chloride. The properties of dark colored polymer, impregnated with the metal complex was then characterized by various spectroscopic technique such as Fourier Transform Infrared (FTIR), Scanning Electron Microscopy/Energy Dispersive X-ray (SEM/EDX), CHNS elemental analysis, BET surface area, X-ray Diffraction (XRD), Thermogravimetric (TGA) and Inductively Coupled Plasma-Optical Emission (ICP-OES) spectroscopy.
Polymers and organic materials that are exposed to sunlight undergo photooxidation, which leads to deterioration of their physical properties. To allow adequate performance under outdoor conditions, synthetic polymers require additives such as antioxidants and UV absorbers. A major problem with optimising polymer formulations to maximise their working life span is that accelerated weathering tests are empirical. The conditions differ significantly from real weathering situations, and samples require lengthy irradiation period. Degradation may not be apparent in the early stages of exposure, although this is when products such as hydroperoxides are formed which later cause acceleration of oxidation. A simple way of quantifying the number of free radicals presents in organic materials following exposure to light or heat is by measuring chemiluminescence (CL) emission. Most polymers emit CL when they undergo oxidative degradation, and it originates from the bimolecular reaction of macroperoxy radicals which creates an excited carbonyl.
Concepts from algebraic geometry such as cones and fans are related to toric varieties and can be applied to determine the convex polytopes and homogeneous coordinate rings of multivariate polynomial systems. The homogeneous coordinates of a system in its projective vector space can be associated with the entries of the resultant matrix of the system under consideration. This paper presents some conditions for the homogeneous coordinates of a certain system of bivariate polynomials through the construction and implementation of the Sylvester-Bèzout hybrid resultant matrix formulation. This basis of the implementation of the Bèzout block applies a combinatorial approach on a set of linear inequalities, named 5-rule. The inequalities involved the set of exponent vectors of the monomials of the system and the entries of the matrix are determined from the coefficients of facets variable known as brackets. The approach can determine the homogeneous coordinates of the given system and the entries of the Bèzout block. Conditions for determining the homogeneous coordinates are also given and proven.
In this study, the rice husk flour-plastic waste composites (RPC) was produced from polypropylene (PP) and high density polyethylene (HDPE) wastes with 30 and 50% rice husk flour (RHF) contents. RPC was made by melt compounding and compression moulding processes. The electrical resistivity, thermal stability and tensile strength of RPC were determined. The RPC was tested in electrical resistivity and tensile strength according to the ASTM D-257 and ASTM D-638 respectively, while thermal stability was tested using thermogravimetric analysis (TGA) method. From the results, high content of RHF reduces all properties, except for tensile modulus of elasticity (TMOE) in tensile strength test. The ability of moisture absorption and the presence of hemicelluloses, cellulose and silica in RHF reduce the electrical resistivity and thermal stability behaviour of RPC from 50% RHF. The good binding elements and filler agglomeration in RPC from 50% RHF improve only TMOE. Insufficient stress transfer and rigid interphase occurred between RHF and plastics during tensile maximum load and elongation at break (Eb) in tensile strength test. In general, RPC from HDPE indicates better thermal stability, tensile modulus of rupture and Eb (in tensile strength test) compared to PP, based on the good behaviour of thermal conductivity, low water absorption, high molecular weight and good elongation properties of HDPE. However, RPC from PP shows good electrical resistance due to the low thermal expansion coefficient of PP.
The electrical resistivity and flexural strength of plastic composites reinforced with pineapple leaf particles (PCPLP) is presented. PCPLP were produced using different plastic materials; Polyethylene (PE) and Polypropylene (PP), and different plastic pineapple leaf particle ratios; 50:50 and 70:30. The PCPLP were tested and evaluated with respect to electrical resistivity and flexural strength according to ASTM D257 and D790, respectively. The results indicate that PCPLP made from PP exhibits better electrical resistance than PE, which may be attributed to the better frequency insulation behaviour ofPP. PCPLP using the higher ratio of 70:30 also exhibited better electrical resistance than the lower 50:50 ratio. Cellulose materials inherently influence the electrical resistance of plastic composites, due to their natural propensity to absorb moisture. The PCPLP produced using a ratio of 50:50 for both PP and PE composites exhibited better MOE results than the 70:30 composites, however the converse is true with respect to the MOR. MOE of PCPLP was increased with increasing pineapple leaf particles content due to the greater matrix stiffness of this natural particle with respect to plastic matrix. However, high percentage offiller particles in the matrix (70:30 ratio) has reduced the toughness in the composite structure due to the lost ofphysical contact between high accumulated particles.