A series of Schiff base ligand, SALMPD, and its mono- and trinuclear Zn(II) metal complexes were synthesised from m-phenylenediamine and salicylaldehyde in alcoholic solution. The synthesis of ligand and mononuclear complex were synthesised using conventional condensation method, while the trinuclear complex was done using microwave-assisted synthesis method. The structure of each compound was elucidated by elemental analysis, infrared and ¹H NMR spectroscopy. The infrared spectrum of SALMPD shows a strong azomethine (C=N) band at 1621.62c m⁻¹, indicates the formation of the ligand. Upon complexation of the mononuclear complex, the C=N infrared band shifted and the disappearing of the phenolic hydrogen signal in ¹H NMR suggesting the chelation between Zinc(II) metal ion and ligand took place when azomethine and phenolic hydrogen deprotonated. The trinuclear complex, Zn3(SALMPD) obtained was consist of two moieties of mononuclear Zn₃(SALMPD), which act as ligands that chelating to the third Zn(II) metal ion through oxygen atom due to the shifting of M-O infrared band from 575.12-540.53cm⁻¹, which serves as a coordination site for the metal ion.
This study focused on the identification of pathogenic bacteria in raw water intake and after sand filtration for drinking water treatment plant during flood event in 2014. The samples was collected from the Lubok Buntar Water Treatment Plant (WTP) and processed through bacterial isolation using chocolate agar as a media. The isolation process conducted based on serial samples dilution and streaking method prior to DNA extraction. Deoxyribonucleic acid (DNA) extraction kit was used to get selected bacteria DNA and further analysis using Polymerase Chain Reaction (PCR) test and electrophoresis to get DNA sequences. The Basic Local Alignment Search Tool (BLAST) analysis was employed to identify the species of the isolated bacteria. As a result, Pantoeaagglomerans and Enterobacter sp. were found in raw and filtered water sample and indicating the same family types. It was concluded that bacteria of the same species were found before and after sand filtration and need to be removed by disinfectant process. The findings also indicated that all the physicochemical parameters measured were within the values prescribed by the Interim National Water Quality Standard (INWQS).
The new complexes [CuL2
(H2
O)2
] and [FeL2
(CH3
O)2
] in which L =
β-mangostin were synthesised and characterised. The structure of the
ligand, β-mangostin was confirmed using NMR and the purity of ligand
was determined using HPLC. Both Cu(II) and Fe(II) complexes were
prepared by reaction between the ligand and the acetate of the metals in
one-step reaction. The synthesised compounds have been characterised
using UV-Visible, FTIR and CHNS analyser. Ligand and metal complexes
were tested against bacteria to assess on their antimicrobial properties using
Minimum Inhibitory Concentrations (MICs) and Minimum Bactericidal
Concentrations (MBCs) method. The elemental analysis and spectra data
suggested octahedral geometry for both Cu(II) and Fe(II) complexes. The
IR spectroscopy revealed that the chelation of Cu2+ and Fe2+ ion occurred
with hydroxyl and carbonyl group at C9
and C1 respectively of β-mangostin.
Both Cu(II) and Fe(II) complexes showed stronger inhibition against
Pseudomonas aeruginosa, Proteus vulgaris, Klebsiella pneumoniae and
Salmonella pneumonia at concentration 900 mg/mL and Escherichia coli
at 450 mg/mL compared to the ligand itself
Heavy metal ions contamination has become more serious which is caused
by the releasing of toxic waterfrom industrial area and landfill that are very
harmful to all living organism especially human and can even cause death
if contaminated in small amount of heavy metal concentration. Currently,
peoples are using classic method namely electrochemical treatment,
chemical oxidation/reduction, chemical precipitation and reverse osmosis
to eliminate the metal ions from toxic water. Unfortunately, these methods
are costly and not environmentally friendly as compared to bioadsorption
method, where agricultural waste is used as biosorbent to remove heavy
metals. Two types of agricultural waste used in this research namely oil
palm mesocarp fiber (Elaesis guineensis sp.) (OPMF) and mangrove bark
(Rhizophora apiculate sp.) (MB) biomass. Through chemical treatment,
the removal efficiency was found to improve. The removal efficiency is
examined based on four specification namely dosage, of biosorbent to
adsorb fourtypes of metalsion explicitly nickel, lead, copper, and chromium.
The research has found that the removal efficiency of MB was lower than
OPMF; whereas, the multiple metals ions removal efficiency decreased in
the order of Pb2+ > Cu2+ > Ni2+ > Cr2+.
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.
Nowadays, development of cable-stayed bridges is increasing around the world. The mitigation of seismic forces to these bridges are obligatory to prevent damages or failure of its structural members. Herein, this paper aimed to determine the near-fault ground motion effect on an existing cablestayed bridge equipped with lead-rubber bearing. In this context, Shipshaw cable-stayed bridge is selected as the case study. The selected bridge has a span of 183.2 m composite deck and 43 m height of steel tower. 2D finite element models of the non-isolated and base isolated bridges are modelled by using SAP2000. Three different near-fault ground motions which are Tabas 1978, Cape Mendocino 1992 and Kobe 1995 were subjected to the 2D FEM models in order to determine the seismic behaviour of the bridge. The near-fault ground motions were applied to the bridge in the longitudinal direction. Nonlinear dynamic analysis was performed to determine the dynamic responses of the bridge. Comparison of dynamic response of nonisolated and base isolated bridge under three different near-fault ground motions were conducted. The results obtained from numerical analyses of the bridge showed that the isolation system lengthened the period of bridge and minimised deck displacement, base shear and base moment of the bridge. It is concluded that the isolation system significantly reduced the destructive effects of near-fault ground motions on the bridge.
The massive growth of construction industry especially in the developing countries results in extensive quarrying activities which ultimately would lead to the depletion of natural resources. Apart from extensive extraction of the natural granite from the earth for concrete production, marble production industry is also majorly contributing to the quarrying activities. In addition, high volume of waste is generated by the marble production industry as 70% of marble is wasted during the production such as quarrying, cutting, processing and others which is environmental unfriendly. In a way to achieve sustainable construction, the present study is to utilise the waste marble in replacing the coarse aggregate in concrete production. The engineering performance including workability, compressive strength, ultrasonic pulse velocity (UPV) and chloride penetration were analysed. The raw waste marble obtained from the industry were crushed and sieved into maximum size 20 mm and used to replace the coarse aggregate at the level of 20%, 40%, 60%, 80% and 100% respectively. Results show that 60% of the replacement level has yield to optimum result by achieving the highest compressive strength and UPV at approximate 5% higher than the control. Meanwhile, the effect on chloride penetration resistance is more significant, i.e. approximate 19% better than the control. However, increasing the replacement level of waste marble has no significant effect on workability, although an increasing trend was observed.
Nowadays, demands in the application of fibre in concrete increase gradually as an engineering material. Rapid cost increment of material causes the increase in demand of new technology that provides safe, efficient and economical design for the present and future application. The introduction ofribbed slab reduces concrete materials and thusthe cost, but the strength of the structure also reduces due to the reducing of material. Steel fibre reinforced concrete (SFRC) has the ability to maintain a part of its tensile strength prior to crack in order to resist more loading compared to conventional concrete. Meanwhile, the ribbed slab can help in material reduction. This research investigated on the bending strength of 2-ribbed and 3-ribbed concrete slab with steel fibre reinforcement under static loading with a span of 1500 mm and 1000 mm x 75 mm in cross section. An amount of 40 kg/m steel fibre of all total concrete volume was used as reinforcement instead of conventional bars with concrete grade 30 N/mm2 . The slab wastested underthree-point bending. Load versus deflection curve was plotted to illustrate the result and to compare the deflection between control and ribbed slab. Thisresearch showsthat SFRCRibbed Slab capable to withstand the same amount of load as normal slab structure, although the concrete volume reduces up to 20%.
A ribbed slab structure has the advantage in the reduction of concrete volume in between the ribs resulting in a lower structural self-weight. In order to overcome the drawbacks in the construction process, the application of steel fibre self-compacting concrete (SCFRC) is seen as an alternative material to be used in the slab. This preliminary investigation was carried out to investigate the flexural behaviour of steel fibre selfcompacting concrete (SCFRC) asthe main material in ribbed slab omitting the conventionalreinforcements. Two samples ofribbed slab were prepared for this preliminary study; 2-ribbed and 3-ribbed in 1 m width to identify the effect of the geometry to the slab’s flexural behaviour. The dimension of both samples is 2.5 m x 1 m with 150 mm thickness. The compressive strength of the mix is 48.6 MPa based on the cubes tested at 28 days. Load was applied to failure by using the four point bending test set-up with simple support condition. The result of the experiment recorded ultimate load carrying capacity at 30.68 kN for the 2-ribbed slab and 25.52 kN for 3-ribbed slab. From the results, the ultimate load of the 2-ribbed sample exceeds 3-ribbed by approximately 20%. This proved that even with lower concrete volume, the sample can still withstand an almost similar ultimate load. Cracks was also observed and recorded with the maximum crack width of 2 mm. It can be concluded that the steel fibres do have the potential to withstand flexural loadings. Steel fibre reduces macro-crack forming into micro-cracks and improves concrete ductility, as well as improvement in deflection. This shows that steel fibre reinforced self-compacting concrete is practical as it offers good concrete properties as well as it can be mixed, placed easier without compaction.
Sewage sludge is a by-product generated within the wastewater treatment process. Severe concern arised as the sludge are massively been dumped to the landfill and it may affect the environment. Many studies had been conducted in reusing the sewage sludge as construction material, where it is one of the optional ways to solve the issue. In this study, dried sewage sludge was incinerated with two different temperatures in order to produce sewage sludge ash (SSA), which are 800°C and 1000°C. Afterfew processes, this SSA then reused in mortar as cementreplacement with the replacement percentage of 5%, 10%, 15% and 20% by weight. The strength performance of mortar specimens was investigated after 7, 28, 60 and 90 days of curing. From the results, it is clearly showed that the compressive strength of all mortar specimens increased when the period of curing was prolonged. Moreover, almost all compressive strength of SSA mortars was higher than the control mortar. Therefore, there is potential to reuse this waste material as part of construction materials and hence, its plays an important role for future researches in minimisation of waste.
The application of concrete filled steel tubes(CFSTs) as composite members has widely been used around the world and is becoming popular day by day for structural application especially in earthquake regions. This paper indicates that an experimental study was conducted to comprehend the behaviour of T-stub end plates connected to concrete filled thin-walled steel tube (CFTST) with different types of bolts and are subjected to pullout load. The bolts used are normal type bolt M20 grade 8.8 and Lindapter Hollo-bolt HB16 and HB20. A series of 10 mm thick T-stub end plates were fastened to 2 mm CFTST of 200 mm x 200 mm in cross-section. All of the specimens were subjected to monotonic pull-out load until failure. Based on testresults, the Lidapter Hollo-boltsshowed better performance compare to normal bolts. The highest ultimate limit load for T-stub end plate fasten with Lindapter Hollo-bolt is four times higher than with normal bolt although all end plates show similar behaviour and failure mode patterns. It can be concluded that T-stub end plate with Lindapter Hollo-bolt shows a better performance in the service limit and ultimate limit states according to the regulations in the design codes.
A conventional plate girder involves the use of transverse intermediate
stiffeners, especially in a slender web to avoid catastrophic failure associated
with shear buckling of the web. In this study, a profiled web was used to
replace the transversely stiffened web. The process involves introducing coldformed
ribs into a flat steel sheet to form alternative stiffeners. This study
therefore seeks to establish comparative performance of conventionally
stiffened plate girders and profiled web girders of a specially formed rib
arrangement with single and also double webs. Nine numbers of specimens
were tested to failure under a three-point-bending system. Failure of all the
profiled web girders, with either a single or double webs, is characterized by
a shorter yield plateau and a steeper descending branch, a failure mode that
is commonly referred to as ‘brittle’. The results of the tests on girders with
profiled steel sheets, PSS(s) have shown that profiling is extremely effective in
increasing the shear buckling load because it moves the sheet material out of
the plane of the web, thereby increasing the rigidity 1.08 to 2.0 times higher
than the equivalent conventional flat web plate girders. The experimental
results also showed that post-buckling capacities are reduced by 30 % to
50 % of their ultimate shear capacities.
It is foreseen that the properties of Polymer Concrete (PC) can be further
enhanced if the PC is bonded to or sandwiched between Glass Fibre Reinforced
Plastic (GFRP) laminates, later termed as PC-GFRP system. In the present
investigation, the performance of PC-GFRP was assessed in terms of its bending
strength and bonding strength between PC and GFRP. Panels of PC size 500
mm × 500 mm × 20 mm were prepared. The panels then were cut into specimens
of appropriate geometry and dimensions required for the tests. Four (4) different
resin contents and different percentages of aggregate of different particle size
distributions were employed in preparing the PC-GFRP specimens. A batch of
PC specimens was layered with a Glass Fibre Reinforced Plastic (GFRP)
laminate on one side (SSL) and the other batch PC specimens were sandwiched
with two GFRP laminates (DSL). The PC-GFRP specimens were tested their
bending strength under three-point load test and bonding strength between
PC as a core material and glued GFRP laminate(s). The results showed that an
increase in the resin content increases the bending strength of the PC regardless
of the aggregate grading. The results also revealed that the PC specimens with
well-graded aggregate recorded the highest bending strength, with coarser
grading resulted in further increase. The bending strength of the PC-GFRP
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.
This paper presents and describes a prototype product code-named SolT2A
which is a system that tracks the position of the sun automatically across the
celestial vault in two axes. This kind of system is typically used in a solar
photovoltaic (PV) system in terrestrial applications to provide electrical
power. It is designed and fabricated due to Malaysia’s location near the
equator, thus the solar altitude crosses the zenith and the azimuth reverses
direction during the year. Thus the use of a static PV system is not maximised
during half of the year. This situation can be addressed by using a two-axes
solar tracking system. So far, Malaysia has not implemented such powertracking
systems. Thus SolT2A has been designed and fabricated to address
the problem by using a combination of electro-mechanical devices with an
element of programming ingenuity and intelligence. Basically SolT2A
measures solar irradiance at four points and makes comparisons in terms of
the intensity received. These data are then analysed and processed by a
controller before being sent to a DC motor that ensures the maximum amount
of solar irradiance received on the PV panels all the time. Thus SolT2A is a
system that maximises the power output of the PV panels to obtain the highest
Several incidents that occurred around the world involving power failure
caused by unscheduled line outages were identified as one of the main
contributors to power failure and cascading blackout in electric power
environment. With the advancement of computer technologies, artificial
intelligence (AI) has been widely accepted as one method that can be applied
to predict the occurrence of unscheduled disturbance. This paper presents
the development of automatic contingency analysis and ranking algorithm
for the application in the Artificial Neural Network (ANN). The ANN is
developed in order to predict the post-outage severity index from a set of preoutage
data set. Data were generated using the newly developed automatic
contingency analysis and ranking (ACAR) algorithm. Tests were conducted
on the 24-bus IEEE Reliability Test Systems. Results showed that the developed
technique is feasible to be implemented practically and an agreement was
achieved in the results obtained from the tests. The developed ACAR can be
utilised for further testing and implementation in other IEEE RTS test systems
particularly in the system, which required fast computation time. On the other
hand, the developed ANN can be used for predicting the post-outage severity
index and hence system stability can be evaluated.
The Internet has been an integral part of the Information and Communication
Technology (ICT) community in recent years. New internet users have been
growing steadily over the years. This has lead to the depletion of new Internet
Protocol (IP) addresses worldwide. To overcome this predicament, the new
Internet Protocol version 6 (IPv6) had been introduced. The existing Internet
Protocol version 4 (IPv4) is expected to be eventually replaced by this IPv6.
The changeover from IPv4 to IPv6 is expected to be implemented progressively.
During this transition period, these two protocols are expected to coexist for
a number of years. IPv4-to-IPv6 transition tools have been designed to facilitate
a smooth transition from IPv4 to IPv6. The two most basic IPv4-to-IPv6
transition tools available are the hybrid stack mechanism and tunneling.
Tunneling is the encapsulation of IPv6 traffic within IPv4 packets so they can
be sent over an IPv4 infrastructure. This project was initiated to set up an
experimental IPv6 testbed, in order to study the performance as well as
transition and migration issues of IPv6 networks under controlled conditions.
This paper looks at how tunneling can be performed over existing internetwork
infrastructure at Fakulti Kejuruteraan Elektrik (FKE), UiTM.
The state space modeling approach was developed to cope with the demand
and performance due to the increase in system complexity, which may have
multiple inputs and multiple outputs (MIMO). This approach is based on timedomain
analysis and synthesis using state variables. This paper describes the
development of a state space representation of a furnace system of a combined
cycle power plant. Power plants will need to operate optimally so as to stay
competitive, as even a small improvement in energy efficiency would involve
substantial cost savings. Both the quantitative and qualitative analyses of the
state space representation of the furnace system are discussed. These include
the responses of systems excited by certain inputs and the structural properties
of the system. The analysis on the furnace system showed that the system is
bounded input and bounded output stable, controllable and observable. In
practice, the state space formulation is very important for numerical computation
and controller design, and can be extended for time-varying systems.
Occupational health is considered as a crucial element in almost every Small
and Medium Industries (SMIs) and it is believed to be one of vital challenges
that can influence productivity and competitiveness. It has been known that
the metal stamping industry involved a lot of materials handling tasks such as
carrying stamped parts from machine to packaging section, transferring moulds
from tools store to machines, sorting the finished products and others.
Appropriate materials handling equipments are not often provided in SMIs
because of the limitation of capital and lack of ergonomics awareness. The
workers have to handle the materials and goods manually. These practices
may lead to occupational injuries particularly back pain and musculoskeletal
injuries. The objectives of the research are to assess and analyze the muscles
activity of workers in metal stamping industry. Three male workers who
performed metal stamping process using manual technique were participated
in the research. Ergonomic assessment associated with Surface
Electromyography (SEMG) was used to capture and interpret the data related
to muscles activity at before and after the ergonomic intervention. For the
purpose of muscle activity assessment, SEMG electrodes were attached to eight
critical muscles: deltoid muscle-medial part (left), deltoid muscle-medial part
(right), trapezius muscle (left), trapezius muscle (right), erector spinae muscle
(left), erector spinae muscle (right), gastrocnemius muscle (left) and
Design and construction of buildings used to be on framed structure
incorporating reinforced concrete, steel or timber as structural member to
transmit load to the foundation. Bricks are normally used as infill materials in
these framed structures. However, research has shown that bricks can also be
used as external and internal masonry bearing walls. With the use of structural
masonry construction method, cheaper and faster construction can be achieved.
Savings are obtained by using less formwork and reinforcing steel, reducing
construction time as lesser frames or none are used, and eliminating waiting
time for the structural concrete to cure or gain their strength. Calcium silicate
and sand cement bricks were tested for their mechanical properties.
Investigations were carried out on six masonry bearing walls. Each unit
measured 1000 mm × 1000 mm and a half brick thick. The structural behaviour
due to compressive axial load was investigated and it shows that both bricks
satisfy the requirement as load bearing wall. However, the study concluded
that sand cement brick wall showed better performance, with maximum lateral
displacement of 3.81mm, vertical deflection of 6.63 mm and ultimate load of
448.13 kN.