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Structural and Optical Properties of Zinc Borotellurite Glass Co-Doped with Lanthanum and Silver Oxide

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Journal of Materials Science and Chemical Engineering 2018年第4期6卷 18-23页

作者： Faznny mohd Fudzi Halimah mohamed Kamari Farah Diana Muhammad Amirah Abd Latif Zaitizila Ismail Glass and Dielectric Lab Physics Department Faculty of Science Universiti Putra Malaysia Serdang Malaysia Photonic Lab Physics Department Faculty of Science Universiti Putra Malaysia Serdang Malaysia

A series of zinc borotellurite glass co-doped with lanthanum and silver oxide with the chemical formula of [{[(TeO2)0.7(B2O3)0.3]0.7(ZnO)0.3}0.96(La2O3)0.04]1-x(Ag2O)x where the molar frac-tion of silver oxide, x = 0.02, 0.04, 0.06, 0.08 and 0.10 had been successfully prepared via the conventional melt-quenching technique. The structural properties of the glasses were unveiled through X-ray Diffraction (XRD) and Fourier Transform Infra-Red (FTIR) spectroscopy while optical properties of the glasses were investigated with Ultra Violet Visible (UV-Vis) spectropho-toscopy. The short range periodic atomic arrangement in the glass matrix that implies the amorphous nature of the glass was confirmed with the presence of a broad hump in the XRD pattern. On the other hand, the three absorption bands observable in the FTIR spectra had proven the existence of BO4, BO3 as well as TeO4 units in the glass network. The absorbance values retrieved from UV-Vis spectroscopy were utilized to calculate the indirect energy band gap and Urbach energy values of the fabricated glass. By employing the equations proposed by Mott and Davis, the obtained indirect energy band gap have val-ues ranging from 2.16 to 4.16 *** decreasing trend in indirect energy band gap and increasing Urbach energy values were related to the increasing num-ber of nonbridging oxygen (NBO) in the glass that is created from the breaking of Te-O-Te or B-O-B bonds after lanthanum as well as silver oxide are incor-porated into the zinc borotellurite glass network.

关键词： Zinc Borotellurite Glass Lanthanum Oxide Silver Oxide Optical Band Gap Urbach Energy

Obstructive sleep apnea among commercial vehicle drivers in Malaysia: Issues and initiatives

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Health 2013年第8期5卷 80-86页

作者： Ameer Batcha Wahida Othman Ilhamah Ahmad Mohamad Suffian mohd Fahmi Aimi mohamed Norlen Shaw Voon Wong Director General Office Malaysian Institute of Road Safety Research Selangor Malaysia Vehicle Safety and Biomechanics Research Centre Malaysian Institute of Road Safety Research Selangor Malaysia

Obstructive Sleep Apnea (OSA) has been identified by many studies as one of the significant contributing factors for motor vehicle accidents. However, only a small number of studies have been conducted in Malaysia. Objective: This paper aims to highlight the prevalence of OSA among truck drivers and express bus drivers in Malaysia and efforts being undertaken to address issues related to OSA among commercial vehicle drivers. Methodology: Two separate studies were conducted: a cross sectional study among truck drivers and secondly among express bus drivers. The screening process for identifying the high risk group for OSA was done using Berlin questionnaire. Meanwhile, among express bus drivers, OSA was confirmed with sleep study using polysomnography test. Result: Screening of risk group of OSA among truck drivers revealed that 14.6% (19) of drivers were categorized as having high risk of OSA while 85.4% (111) having low risk of OSA. While, in another study, polysomnography test among express bus drivers showed that 83 (28.7%) had mild OSA, 26 (9.0%) had AHI moderate OSA, and 19 drivers (6.6%) severe OSA. Conclusion: This paper highlighted the issues of OSA among commercial vehicle drivers in Malaysia. With an alarming high prevalence, OSA should be a major road safety concern in this country. A special study focusing on sleep and fatigue related crashes may need to be conducted to complement the current studies and full implementation of existing efforts and initiatives to address OSA in road crashes should be realized by the relevant authorities.

关键词： OSA Obstructive Sleep Apnea Commercial Vehicle Drivers

Synthesis and controlled release of cloprop herbicides from cloprop-layered double hydroxide and cloprop-zinc-layered hydroxide nanocomposites

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Open Journal of Inorganic Chemistry 2014年第1期4卷 1-9页

作者： Norhayati Hashim mohd Zobir Hussein Illyas Md Isa Azlan Kamari Azmi mohamed Adila Mohamad Jaafar Hafsah Taha Department of Chemistry Faculty of Science and Mathematics Universiti Pendidikan Sultan Idris Tanjong Malim Malaysia Department of Chemistry Faculty of Science and Mathematics Universiti Pendidikan Sultan Idris Tanjong Malim Malaysia Nanotechnology Research Centre Faculty of Science and Mathematics Universiti Pendidikan Sultan Idris Tanjong Malim Malaysia Department of Chemistry Faculty of Science Universiti Putra Malaysia Serdang Malaysia

Two phenoxyherbicide nanocomposites, namely cloprop-layered double hydroxide and cloprop-zinc- layered hydroxide nanocomposites, have been synthesized by using co-precipitation and direct reaction method. PXRD pattern showed an expansion of interlayer spacing with the value of 21.0 Åand 22.7 Åfor cloprop-layered double hydroxide and cloprop-zinc-layered hydroxide nanocomposite, respectively. It is evident from FTIR and elemental analyses that both nanocomposites were successfully intercalated between the interlayers of layered metal hydroxide. Controlled release of cloprop anion from interlayer of nanocomposites for both cloprop-layered double hydroxide and cloprop-zinc-layered hydroxide nanocomposite into phosphate solution was rapid initially and slow thereafter. The percentage of accumulated release of cloprop anion from cloprop-zinc-layered hydroxide nanocomposite was slightly higher than that from cloprop-layered double hydroxide nanocomposite. Kinetic behavior of cloprop release was governed by pseudo-second-order for cloprop-layered double hydroxide nanocomposite while parabolic diffusion for cloprop-zinc-layered hydroxide nanocomposite. Results from this study highlight the potential of both nanocomposites as capsulated material for controlled release of cloprop phenoxyherbicides anion.

关键词： Cloprop Cloprop-Layered Double Hydroxide Cloprop-Zinc-Layered Hydroxide Nanocomposite Controlled Release Kinetic Study

Development of Design Response Spectra Based on Various Attenuation Relationships at Specific Location

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Journal of Civil Engineering and Architecture 2013年第12期7卷 1501-1506页

作者： Hapsa Husen Taksiah Abdul Majid Fadzli mohamed Nazri mohd Rashwan Arshad Ade Faisal Sift Khadijah Che Osmi Civil Engineering Department Faculty of Engineering Universiti Pertahanan Nasional Malaysia Kuala Lumpur 57000Malaysia School of Civil Engineering Universiti Sains Malaysia Pulau Pinang 14300 Malaysia

Peninsular Malaysia is located and lies in a low seismic region. Although Malaysia is not located in the active fault seismic area, it is closed to the Sumatran active seismic zones. Tall building are fIequently felt the tremor generated fTom Sumatran subduction and fault zones especially in the west cost of Peninsular Malaysia such as Johor Bahru, Kuala Lumpur and Penang. Existing design response spectra was developed based on attenuation relationship for each subduction and fault zone. In this study, the design response spectra were developed based on various attenuation relationships for selected location in Kuala Lumpur area, namely, Mutiara Damansara, Bandar Petaling Jaya and Bandar Puteri Puchong. The development of design response spectra based on various attenuation relationships is more reliable in selecting the appropriate attenuation relationship for the study area. Seven attenuations have been chosen and results show that Megawati et al. are the most appropriate attenuation relation for fault zone, where the predicted PGA （peak ground acceleration） is 0.0187 g which is the proposed PGA value for this study area. This study also found that most of soil in the study area can be categorized into SD （stiff soil） according to site classification in the NEHRP 2000 Provision/UBC 97. Bandar petaling Jaya was found to be highest AF （amplification factor） of 3.74 for stiff soil and Mutiara Damansara with AF of 2.67 for very dense soil or soft rock. The proposed design response spectra for each location were developed based on UBC 1997 （Uniform Building Code 1997）. The peak RSA （response spectrum acceleration） of 0.30 g for soil type SD for Bandar Petaling Jaya is the maximum level of acceleration on the soil surface with a period range of 0.10 to 0.52 seconds. All these values can be used for the seismic safety evaluation of existing structures and as a guideline in designing new structures to resist future earthquake, within the study area.

关键词： Attenuation relationship PGA (peak ground acceleration) response spectrum acceleration response spectra Sumatra subduction zone Sumatra fault zone.

Assessment of Physical and Mechanical Properties of Cement Panel Influenced by Treated and Untreated Coconut Fiber Addition

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Assessment of Physical and Mechanical Properties of Cement P...

Nicotine Content in Electronic Cigarette Refill Solutions and Its Release in Aerosols

2011 International Conference on Physics Science and Technology (ICPST 2011)

作者： Alida Abdullah Shamsul Baharin Jamaludin mohamed Iylia Anwar Mazlee mohd Noor Kamarudin Hussin School of Materials Engineering Universiti Malaysia Perlis

This project was conducted to produce a cement panel with the addition of treated and untreated coconut fiber in cement panel. Coconut fiber was added to replace coarse aggregate（sand） in this cement panel. In this project, the ratios used to design the mixture were 1:1:0, 1:0.97:0.03, 1:0.94:0.06, 1:0.91:0.09（cement: sand: coconut fiber）. The water cement ratio was constant at 0.55. The sizes of sample tested were, 160 mm x 40 mm x 40 mm for compression test, and 100 mm x 100 mm x 40 mm for density, moisture content and water absorption tests. After curing samples for 28 days, it was found that the addition of coconut fiber, further increase in compressive strength of cement panel with untreated coconut fiber. Moisture content of cement panel with treated coconut fiber increased with increasing content of coconut fiber whereas water absorption of cement panel with untreated coconut fiber increased with increasing content of coconut fiber. The density of cement panel decreased with the addition of untreated and treated coconut fiber.

关键词： Treated coconut fiber cement panel compressive strength density moisture content water absorption

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Journal of Environmental Protection 2019年第10期10卷 1317-1332页

作者： Sharifah Mazrah Sayed mohamed Zain Sara Khalida Jamal Khair Nadia Mohamad mohd Fairulnizal Md. Noh Dinash Aravind Radhakrishnan Environmental Health Research Centre Institute for Medical Research Ministry of Health Malaysia Selangor Malaysia National Pharmaceutical Regulatory Agency Ministry of Health Malaysia Selangor Malaysia Nutrition Metabolic and Cardiovascular Research Centre Institute for Medical Research Ministry of Health Malaysia Selangor Malaysia.

Electronic cigarette (EC) is a device that imitates conventional cigarettes, which vaporizes a solution, with or without nicotine. This study evaluates the nicotine levels in EC refill solutions, its release in aerosols and comparison to the amount stated on the label. Seventy-two (72) different EC refill solutions were obtained from local shops in Selangor, Malaysia consisting of 40 nicotine-containing (3 - 12 mg) and 32 nicotine-free (0 mg) solutions. Aerosols were obtained by using an air tight syringe connected to an EC device to draw aerosol through an XAD-4 sorbent tube that trapped the nicotine. Nicotine in solution and aerosol samples are analyzed using gas chromatography-mass spectrometry equipment. Quantified nicotine in 40 nicotine-containing solutions ranged from 0.224 - 17.306 mg/mL. Nicotine is detected in 3 of the 32 nicotine-free solutions. Percentage of nicotine released into aerosols from refill solutions varied from 0.54% - 28.2%. Out of the 40 samples, thirty-two (32) had nicotine content that violated by more than ±10% from the value on the label. In comparing the labels, 19 samples have 0.3% - 77% higher nicotine level and 13 samples have 0.2% - 96.3% lower nicotine content. The inconsistency between the labelled and true levels of nicotine content indicates that commercial information may be misleading. The presence of nicotine in the nicotine-free refill solutions and higher nicotine content in aerosols may be addictive and may have negative health effects on users.

关键词： Electronic Nicotine Delivery Systems Tobacco Products Tobacco Industry Vapers

Gross Pollutants Study in Urban Areas under Tropical Climates

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Journal of Civil Engineering and Architecture 2014年第1期8卷 107-114页

作者： Lariyah mohd Sidek Hidayah Basri mohamed Roseli Zainal Abidin Lira Chow Hock Md Nasir Md Nor Nor Azazi Zakaria Centre for Sustainable Technology and Environment (CSTEN) College of Engineering Universiti Tenaga Nasional Kajang43000 Malaysia Drainage and Irrigation Department Humid Tropics Centre Kuala Lumpur Kuala Lumpur 50480 Malaysia Drainage and lrrigation Department River Basin & Coastal Zone Management Kuala Lumpur 50626 Malaysia River Engineering and Urban Drainage Centre (REDAC) Universiti Sains Malaysia Nibong Tebal 14300 Malaysia

Gross pollutants are the primary targeted pollutants in urban catchment management for urban water quality improvement as well as mitigation of flood. Apart from aesthetically unattractive because of its visibility, gross pollutants also contributes to degradation of river water quality and loss of aquatic habitat as it carries harmful pollutants such as oxygen demanding material, hydrocarbons and heavy metals. This study analyzed trend of gross pollutant generated from two urban residential areas located in Selangor, Malaysia. The median value of gross pollutant load obtained fi＇om the Amanah Apartment and Bandar Botanic are 347.41 kg/ha/year and 32.46 kg/ha/year, respectively. Relationship between gross pollutant wet load with rainfall depths was derived using regression equation. A significant trend of increasing gross pollutant wet load into drainage system with increasing rainfall depth was observed. The behavior of pollutant load is related to the one observed in Australia.

关键词： Gross pollutant load urban stormwater quality urban stormwater management.

Removal of Cu(II), Pb(II) and Zn(II) Ions from Aqueous Solutions Using Selected Agricultural Wastes: Adsorption and Characterisation Studies

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Journal of Environmental Protection 2014年第4期5卷 289-300页

作者： Siti Najiah mohd Yusoff Azlan Kamari Wiwid Pranata Putra Che Fauziah Ishak Azmi mohamed Norhayati Hashim Illyas Md Isa 1Department of Chemistry Faculty of Science and Mathematics Universiti Pendidikan Sultan Idris Tg. Malim Perak Malaysia 2Nanotechnology Research Centre Faculty of Science and Mathematics Universiti Pendidikan Sultan Idris Tg. Malim Perak Malaysia Department of Chemistry Faculty of Science and Mathematics Universiti Pendidikan Sultan Idris Tg. Malim Perak Malaysia Department of Land Management Faculty of Agriculture Universiti Putra Malaysia Serdang Selangor Malaysia

The feasibility of durian tree sawdust (DTS), coconut coir (CC) and oil palm empty fruit bunch (EFB) as low-cost biosorbents for the removal of Cu(II), Pb(II) and Zn(II) ions from aqueous solutions was investigated. The effects of solution pH and initial metal concentration on adsorption capacity were examined in batch experiments. The affinity and the adsorption capacity of DTS, CC and EFB were evaluated. The adsorption behaviour of Cu(II), Pb(II) and Zn(II) ions onto DTS, CC and EFB was described using Freundlich and Langmuir isotherm models. The separation factor (RL) analysis suggests that the removal of metal ions onto three agricultural wastes studied was favourable. The maximum adsorption capacities (Q) estimated from the Langmuir isotherm model for Cu(II), Pb(II) and Zn(II) were 18.42, 20.37 and 22.78 mg/g for DTS, 18.38, 37.04 and 24.39 mg/g for CC, and 26.95, 37.59 and 21.19 mg/g for EFB, respectively. The characterisation studies were carried out using Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectrometer (EDX) and Fourier Transform Infrared Spectrometer (FTIR). The surface morphology of the biosorbents changed significantly following interaction with metal ions. The primary adsorption mechanism was complexation between metal ions and binding sites of biosorbents. Both hydroxyl and amine groups are the main binding sites in DTS, CC and EFB.

关键词： Adsorption Characterisation Metals Durian Tree Sawdust Coconut Coir Oil Palm Empty Fruit Bunch

Biosorption of Cu(II), Pb(II) and Zn(II) Ions from Aqueous Solutions Using Selected Waste Materials: Adsorption and Characterisation Studies

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Journal of Encapsulation and Adsorption Sciences 2014年第1期4卷 25-35页

作者： Wiwid Pranata Putra Azlan Kamari Siti Najiah mohd Yusoff Che Fauziah Ishak Azmi mohamed Norhayati Hashim Illyas Md Isa Department of Chemistry Faculty of Science and Mathematics Universiti Pendidikan Sultan Idris Tg. Malim Perak Malaysia Department of Chemistry Faculty of Science and Mathematics Universiti Pendidikan Sultan Idris Tg. Malim Perak Malaysia Nanotechnology Research Centre Faculty of Science and Mathematics Universiti Pendidikan Sultan Idris Tg. Malim Perak Malaysia Department of Land Management Faculty of Agriculture Universiti Putra Malaysia Serdang Selangor Malaysia

The efficacy of coconut tree sawdust (CTS), eggshell (ES) and sugarcane bagasse (SB) as alternative low-cost biosorbents for the removal of Cu(II), Pb(II) and Zn(II) ions from aqueous solutions was investigated. Batch adsorption studies were carried out to evaluate the effects of solution pH and initial metal concentration on adsorption capacity. The optimum biosorption condition was found at pH 6.0, 0.1 g biomass dosage and at 90 min equilibrium time. The adsorption data were fitted to the Freundlich and Langmuir isotherm models. The adsorption capacity and affinity of CTS, ES and SB were evaluated. The Freundlich constant (n) and separation factor (RL) values suggest that the metal ions were favourably adsorbed onto biosorbents. The maximum adsorption capacities (Q) estimated from the Langmuir isotherm model for Cu(II), Pb(II) and Zn(II) were 3.89, 25.00 and 23.81 mg/g for CTS, 34.48, 90.90 and 35.71 mg/g for ES, and 3.65, 21.28 and 40.00 mg/g for SB, respectively. The characterisation studies were performed using Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectrometer (EDX) and Fourier Transform Infrared Spectrometer (FTIR). Interaction with metal ions led to the formation of discrete aggregates on the biosorbents surface. The metal ions bound to the active sites of the biosorbents through either electrostatic attraction or complexation mechanism.

关键词： Adsorption Characterisation Metal Ions Coconut Tree Sawdust Eggshell Sugarcane Bagasse