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Kesan masa pengeraman nanozarah zink oksida yang dihasilkan menggunakan afrons gas koloid
No full textNanozarah zink oksida telah disintesis menggunakan afrons gas koloid sebagai acuan. Zink sulfat (ZnSO4.7H2O) dan gas ammonia digunakan sebagi bahan tindak balas. Masa pengeraman yang dikaji adalah 2 jam dan 18 jam. Daripada analisis mikroskop elektron imbasan, morfologi nanohelaian dapat diperhatikan dengan ketebalan helaian 125 nm hingga 200 nm. Daripada analisis spektroskopi ultra lembayung-boleh nampak, saiz purata yang dianggarkan bagi sampel nanozarah zink oksida yang disintesis dengan masa pengeraman 2 jam adalah 2.03 nm dan 2.1 nm untuk sampel yang dieramkan selama 18 jam
Pencirian geomekanik jasad batuan dengan menggunakan kaedah seismos: nisbah poisson
No full textParameter mekanik seperti nisbah Poisson merupakan parameter input kejuruteraan batuan terutamanya dalam perisian komputer model berangka. Kaedah seismos digunakan untuk menentukan nisbah Poisson jasad batuan segar (gred I), terluluhawa sedikit (gred II), terluluhawa sederhana (gred III) dan tinggi (gred IV). Nisbah Poisson setiap lapisan jasad batuan dikira berdasarkan nilai purata halaju gelombang mampatan (Vp) dan gelombang ricih (Vs) pada kedalaman tertentu. Halaju gelombang mampatan (Vp) diperoleh daripada survei seismos biasan dan halaju gelombang ricih (Vs) diperoleh daripada survei analisis spektral gelombang permukaan (SASW) atau analisis gelombang permukaan berbilang saluran (MASW). Sebanyak 66 ujian seismos telah dijalankan pada 9 cerun jasad batuan iaitu 6 ujian di atas 1 cerun jasad batuan granit di JKR kuari Bukit Penggorak, Kuantan, Pahang; 26 ujian di atas 4 cerun jasad batuan granit di Kuari Kajang Rock, Semenyih, Ulu Langat, Selangor; 12 ujian di atas 1 cerun jasad batuan granit di Lebuhraya Silk Kajang (km 14.6) Selangor; 14 ujian di atas 2 cerun jasad batuan syis di Jalan Kuala Kubu Baru-Bukit Fraser (km 15), Selangor dan 8 ujian di atas 1 cerun jasad batuan kuarzit di Section U10, Bukit Cherakah, Shah Alam, Selangor. Daripada ujian seismos, nilai maksimum nisbah Poisson jasad batuan yang bergred I, II, III dan IV ialah 0.295, 0.335, 0.355 dan 0.364. Nilai minimum nisbah Poisson jasad batuan yang mempunyai gred I, II, III dan IV ialah 0.215, 0.299, 0.334 dan 0.337. Nilai purata nisbah Poisson untuk jasad batuan bergred I, II, III dan IV ialah 0.274, 0.320, 0.345 dan 0.345. Nilai nisbah Poisson jasad batuan menjadi semakin besar apabila gred terluluhawa menjadi semakin besar. Nilai purata nisbah Poisson jasad batuan gred II, III dan IV bertambah sebanyak 16.8%, 25.9% dan 25.9% jika dibandingkan dengan jasad batuan gred I. Keadaan ini berlaku kerana perubahan retakan pada jasad batuan gred I adalah lebih besar apabila mengalami proses terluluhawa. Perubahan retakan menjadi semakin kecil apabila mengalami proses terluluhawa seterusnya. Tiada perubahan retakan berlaku pada jasad batuan gred III apabila menjadi jasad batuan gred I
Predictor-corrector block iteration method for solving ordinary differential equations
No full textPredictor-corrector two point block methods are developed for solving first order ordinary differential equations (ODEs) using variable step size. The method will estimate the solutions of initial value problems (IVPs) at two points simultaneously. The existence multistep method involves the computations of the divided differences and integration coefficients when using the variable step size or variable step size and order. The block method developed will be presented as in the form of Adams Bashforth - Moulton type and the coefficients will be stored in the code. The efficiency of the predictor-corrector block method is compared to the standard variable step and order non block multistep method in terms of total number of steps, maximum error, total function calls and execution times
Kesan aplikasi perisian cerita interaktif semasa mengajarkan kemahiran bacaan dan kefahaman dalam kalangan murid tahun 4 di Brunei Darussalam
No full textThe purpose of this study was to assess students’ achievement in reading and
comprehension when using traditional method and application of interactive computer
aplication. In addition, this study also evaluates the impact of using CD-ROM interactive
stories in the teaching of reading including the aspect of knowledge, morphology and
syntax among the average students. A quasi-experimental method was used in this study.
The study sample involved 52 students of year 4 from one primary school in Brunei Muara
District. The sample was divided into two groups, the experimental group and the control
group. Each group consisted of 26 average students comprising 13 boys and 13 girls. The
results of this study were analyzed using t-test independent samples to assess whether there are significant differences in the mean performance of reading comprehension,
mastery of morphology and syntax between the experimental and control groups in pre
and post test. T-test analysis showed that there was a significant difference in the mean of
reading comprehension performance between the experimental group and the control
group in the post-test. The findings also show that the use of CD-ROM interactive stories in
teaching reading and comprehension not only enhance students' performance in
comprehension, but also enhance other aspects of language such as the morphology and
synta
Optimization of microencapsulation process for self-healing polymeric material
No full textA series of poly(urea-formaldehyde) (PUF) microcapsules filled with dicyclopentadiene (DCPD) was successfully prepared by in situ polymerization. The effect of diverse process parameters and ingredients on the morphology of the microcapsules was observed by SEM, optical microscopy (OM) and digital microscopy. Different techniques for the characterization of the chemical structure and the core content were considered such as FT-IR and 1H-NMR as well as the characterization of thermal properties by DSC. High yields of free flowing powder of spherical microcapsules were produced. The synthesized microcapsules can be incorporated into another polymeric host material. In the event the host material cracks due to excessive stress or strong impact, the microcapsules would rupture to release the DCPD, which could polymerize to repair the crack
Effect of pro-degradant additive on photo-oxidative aging of polypropylene film
No full textThis paper describes the effect of pro-degradant additives (PDA) on photo-oxidative aging of polypropylene (PP) films after being time accelerated in UV-weathering chamber. Thin films (0.12 mm) containing these additives were prepared by sheeting process. The effect of UV on PP films in the presence of these additives was investigated. Changes in the PP films appearance, tensile properties and carbonyl index (CI) were used to investigate the degradation behavior. The films became completely pulverised after 100 h of photo-oxidative treatment and could not be tested further. Films containing PDA showed rapid loss in tensile properties within 100 h of photo-oxidative aging. In addition, the CI results of photo-oxidative films increased with increasing PDA amount within the time interval of aging and the activity was due to the mechanism reaction of PP with PDA particles. During the aging process the material becomes denser due to tighter packing and incorporation of oxygen into the amorphous regions of the polymer. The results indicated that the presence of PDA contributed to the photo degradation and the activity was very much influenced by the amount PD
Land-based tax capacity and tax effort of the State Governments in Peninsular Malaysia: a Representative Revenue System (RRS) approach
No full textThe Auditor General Report 2004 revealed that seven out of 13 states in Malaysia are facing dire financial
difficulties to the extent of being qualified as at the verge of bankruptcy. One of the solutions proposed
would be to devolve more tax responsibilities to the state governments. However, some authors have argued that the Malaysian state governments have not been using their tax base efficiently and the devolution of more tax responsibilities towards them will only result in more inefficiency. It is thus important to gauge the fiscal effort exerted by the state governments before any attempts being made towards increasing tax responsibilities of the state governments. The main objective of this article is to
measure the fiscal effort and capacity of the state governments in Peninsular Malaysia. In order to achieve
this, we will use the Representative Revenue System (RRS)/ Representative Tax System (RTS) approach.
This paper will discuss the preliminary findings of the research using the 2008 data. Our results show that
more-developed states tend to have higher index of tax effort compared to the less-developed ones. It is
also shown that state governments with high fiscal effort are in a relatively better fiscal position.
However, tax arrears do not seem to correlate with the level of tax effort
