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The main aim of this study was to evaluate the potential effect of dispersion, thermal radiation, and explosion from a poly-bed pressure swing adsorption (PSA) unit with its surrounding facility to determine its safety distance. Thus, the Shell FRED (fire, release, explosion, and dispersion) consequence modeling was used to predict the impact of a release scenario and assist in designing, developing, and maintaining safe operation. This study was intended to calculate dispersion contours to 50 lower flammable limit (LFL) and 100 LFL, thermal impacts of radiation flux levels of 4, 5, 12.5, and 37.5 kW/m2 at a distance, and including explosive effects of 0.1, 0.2, and 0.35 bar to the chosen target. Based on the findings, it was found that, to avoid exposure to heat radiation of 12.5 kW/m2 from the PSA unit, equipment should be located at a minimum distance of 20.84 m. Meanwhile, process modules and buildings must be located at a minimum distance of 13.8 m. The explosive nature of hydrogen makes on-site handling and storage more challenging than fossil fuels. The findings of this study will have important implications for the future handling and storage of hydrogen as a potential fuel.

The main aim of this study was to evaluate the potential effect of dispersion, thermal radiation, and explosion from a poly-bed pressure swing adsorption (PSA) unit with its surrounding facility to determine its safety distance. Thus, the Shell FRED (fire, release, explosion, and dispersion) consequence modeling was used to predict the impact of a release scenario and assist in designing, developing, and maintaining safe operation. This study was intended to calculate dispersion contours to 50 lower flammable limit (LFL) and 100 LFL, thermal impacts of radiation flux levels of 4, 5, 12.5, and 37.5 kW/m2 at a distance, and including explosive effects of 0.1, 0.2, and 0.35 bar to the chosen target. Based on the findings, it was found that, to avoid exposure to heat radiation of 12.5 kW/m2 from the PSA unit, equipment should be located at a minimum distance of 20.84 m. Meanwhile, process modules and buildings must be located at a minimum distance of 13.8 m. The explosive nature of hydrogen makes on-site handling and storage more challenging than fossil fuels. The findings of this study will have important implications for the future handling and storage of hydrogen as a potential fuel.

Introduction: Falling from heights can be a serious and potentially life-threatening hazard. In Malaysia, falls from heights are one of the leading causes of workplace accidents and fatalities. The Malaysian Department of Occupational Safety and Health (DOSH) reported that the year 2021 recorded an alarmingly high number of fatalities, of which the majority of the injuries were due to falls from heights. Objective: The purpose of this study is to understand the relationship between the different variables associated with fatal falls from heights, which will help identify potential areas to work on to prevent these types of injuries. Methods: The study analyzed 3,321 fatal falls from height accidents from 2010 to 2020 DOSH data. Data were cleaned and normalized to extract relevant information for analysis, with agreement on variables and reliability achieved through independent sampling. Results: This study found that general workers were the most vulnerable category to fatal falls, with a 32% yearly average, whereas supervisors were the least vulnerable, with 4%. Roofers recorded a yearly fatal falls average of 15.5%, followed by electricians with 12%. Cramer’s V results ranged from negligible, weak, and strong correlations; strong to moderate correlation between the dates of injuries and the factors used in this study, whereas the direct and root causes recorded a weak to negligible correlation with the rest of the variables. Conclusions: This study provided a better understanding of the working conditions of the Malaysian construction industry. By analyzing fall injury patterns and uncovering the factors, direct and root causes relationship with other variables, it was clear how severe the Malaysian workplace conditions were. Practical Applications: This study will help better understand fatal fall injuries in the Malaysian construction industry and help develop prevention measures based on the uncovered patterns and associations.

Introduction: Falling from heights can be a serious and potentially life-threatening hazard. In Malaysia, falls from heights are one of the leading causes of workplace accidents and fatalities. The Malaysian Department of Occupational Safety and Health (DOSH) reported that the year 2021 recorded an alarmingly high number of fatalities, of which the majority of the injuries were due to falls from heights. Objective: The purpose of this study is to understand the relationship between the different variables associated with fatal falls from heights, which will help identify potential areas to work on to prevent these types of injuries. Methods: The study analyzed 3,321 fatal falls from height accidents from 2010 to 2020 DOSH data. Data were cleaned and normalized to extract relevant information for analysis, with agreement on variables and reliability achieved through independent sampling. Results: This study found that general workers were the most vulnerable category to fatal falls, with a 32% yearly average, whereas supervisors were the least vulnerable, with 4%. Roofers recorded a yearly fatal falls average of 15.5%, followed by electricians with 12%. Cramer’s V results ranged from negligible, weak, and strong correlations; strong to moderate correlation between the dates of injuries and the factors used in this study, whereas the direct and root causes recorded a weak to negligible correlation with the rest of the variables. Conclusions: This study provided a better understanding of the working conditions of the Malaysian construction industry. By analyzing fall injury patterns and uncovering the factors, direct and root causes relationship with other variables, it was clear how severe the Malaysian workplace conditions were. Practical Applications: This study will help better understand fatal fall injuries in the Malaysian construction industry and help develop prevention measures based on the uncovered patterns and associations.

Fatal falls from heights accidents represent a threat to any industry's development and progress. It is crucial to understand how these accidents evolve from a simple ‘near miss‘ into a ‘fatal accident‘. In recent years, Malaysia's construction industry suffered an increasingly alarming number of fatal falls from heights accidents. Fatal accident numbers that were reported and investigated had a noticeable increase from 2013 to 2017. The purpose of this study is to assess the risks associated with falls from heights fatal accidents, which ultimately will be able to help provide the data for proactive prevention against this type of accident. This study used two different risk assessment methods. The first risk assessment consists of a statistical analysis of the collected data. The second risk assessment includes a fault tree analysis. Data extracted from the Department of Occupational Safety and Health Malaysia were used as input for the risk assessment. Results indicate several significant causes that need to be handled immediately. Some of these causes are failure to wear Personal Protective Equipment with an 85.93% occurrence rate, the lack of supervision and leadership with 89.84%, and the absence of work standards or the inability to follow them correctly with 85.15%. This study will help identify root causes, immediate causes, accidents scenarios, and finally the probability and urgency when investigating fatal falls from heights.

Fatal falls from heights accidents represent a threat to any industry's development and progress. It is crucial to understand how these accidents evolve from a simple ‘near miss‘ into a ‘fatal accident‘. In recent years, Malaysia's construction industry suffered an increasingly alarming number of fatal falls from heights accidents. Fatal accident numbers that were reported and investigated had a noticeable increase from 2013 to 2017. The purpose of this study is to assess the risks associated with falls from heights fatal accidents, which ultimately will be able to help provide the data for proactive prevention against this type of accident. This study used two different risk assessment methods. The first risk assessment consists of a statistical analysis of the collected data. The second risk assessment includes a fault tree analysis. Data extracted from the Department of Occupational Safety and Health Malaysia were used as input for the risk assessment. Results indicate several significant causes that need to be handled immediately. Some of these causes are failure to wear Personal Protective Equipment with an 85.93% occurrence rate, the lack of supervision and leadership with 89.84%, and the absence of work standards or the inability to follow them correctly with 85.15%. This study will help identify root causes, immediate causes, accidents scenarios, and finally the probability and urgency when investigating fatal falls from heights.

This work investigates possible factors that lead to acetone-water explosion in a hydrothermal extraction reactor that happened in our laboratory. To begin with, acetone-water reactivity was checked in CAMEO. Next, pressure build-up curves at varying operating conditions were simulated in Aspen Batch Modeler. Analysis of variance (ANOVA) was conducted in IBM SPSS Statistical Software to determine the most significant factors causing the explosion. Results from CAMEO showed that the explosion was a boiling liquid expanding vapour explosion (BLEVE). Outputs from Aspen simulation indicated that the reactor pressure rise increased with the increment of acetone ratio, heating temperature and reactant total volume. The reactor wall ruptured as the pressure exceeded the maximum allowable working pressure. IBM SPSS showed that the heating temperature was the most significant factor causing the pressure to build-up within the reactor, followed by the acetone-water ratio and total reactant volume. Among all three factors, the heating temperature added to largest pressure build-up, especially when the temperature was increased near to 360 °C. The time required to trigger explosion was predicted to be within 13.8–15 min of heating.

This work investigates possible factors that lead to acetone-water explosion in a hydrothermal extraction reactor that happened in our laboratory. To begin with, acetone-water reactivity was checked in CAMEO. Next, pressure build-up curves at varying operating conditions were simulated in Aspen Batch Modeler. Analysis of variance (ANOVA) was conducted in IBM SPSS Statistical Software to determine the most significant factors causing the explosion. Results from CAMEO showed that the explosion was a boiling liquid expanding vapour explosion (BLEVE). Outputs from Aspen simulation indicated that the reactor pressure rise increased with the increment of acetone ratio, heating temperature and reactant total volume. The reactor wall ruptured as the pressure exceeded the maximum allowable working pressure. IBM SPSS showed that the heating temperature was the most significant factor causing the pressure to build-up within the reactor, followed by the acetone-water ratio and total reactant volume. Among all three factors, the heating temperature added to largest pressure build-up, especially when the temperature was increased near to 360 °C. The time required to trigger explosion was predicted to be within 13.8–15 min of heating.

Working at heights has always been a concern for the process industry and construction industry. According to recent statistics, falls from heights are the leading cause for at least a third of all construction accidents, based on the accident reports from Malaysia, United States of America (USA) and Great Britain. Therefore, the aim of this research is to investigate the contributing factors for fatal accidents due to falls from heights based on published official data by government agencies such as Department of Occupational Safety and Health (DOSH) in Malaysia and Occupational Safety and Health and Administration (OSHA) in the USA. Thorough risk analysis of accidents due to falls from heights is needed as a step to improve the safety of workers and reduce the number of fatalities. The methodology used was developed through an in-depth literature review from relevant publications that discussed falls from heights investigations ranging from individual characters to management commitment and site conditions. The data is available and accessible to the public via OSHA and DOSH and can be obtained by browsing their websites. The data were analysed based on the relevant understanding of the description mentioned in the accident reports and its relationship with the contributing factors. Eventually, from the analysis, the factors which affect more the numbers of fatal accidents due to falls from heights were obtained. In this study, 105 fatal accidents due to falls from heights from Malaysia data and 101 fatal accidents from USA data were selected through a precise selecting process and analysed to determine which factor was the highest contributor to increasing the number of fatal workplace accidents due to falls from heights. Results indicate that a lack of effective management is the highest contributor to falls from height fatal accidents.

Working at heights has always been a concern for the process industry and construction industry. According to recent statistics, falls from heights are the leading cause for at least a third of all construction accidents, based on the accident reports from Malaysia, United States of America (USA) and Great Britain. Therefore, the aim of this research is to investigate the contributing factors for fatal accidents due to falls from heights based on published official data by government agencies such as Department of Occupational Safety and Health (DOSH) in Malaysia and Occupational Safety and Health and Administration (OSHA) in the USA. Thorough risk analysis of accidents due to falls from heights is needed as a step to improve the safety of workers and reduce the number of fatalities. The methodology used was developed through an in-depth literature review from relevant publications that discussed falls from heights investigations ranging from individual characters to management commitment and site conditions. The data is available and accessible to the public via OSHA and DOSH and can be obtained by browsing their websites. The data were analysed based on the relevant understanding of the description mentioned in the accident reports and its relationship with the contributing factors. Eventually, from the analysis, the factors which affect more the numbers of fatal accidents due to falls from heights were obtained. In this study, 105 fatal accidents due to falls from heights from Malaysia data and 101 fatal accidents from USA data were selected through a precise selecting process and analysed to determine which factor was the highest contributor to increasing the number of fatal workplace accidents due to falls from heights. Results indicate that a lack of effective management is the highest contributor to falls from height fatal accidents.

Vapor cloud explosion is one of the major threats to Floating, Production, Storage and Offloading (FPSO) facilities due to its congested and confined nature. Reduction in explosion overpressure can be achieved by improving the ventilation in FPSO. During early design stage of FPSO, designers consider providing grated process decks to improve the ventilation. However, there is limited research on the comparison of the explosion overpressure between the grated deck and the traditional plated deck. In this study, Vapor Cloud Explosion perspective of plated versus grated process deck in typical FPSO was evaluated by utilizing Det Norske Veritas’s (DNV) SAFETI OFFSHORE modelling tool. Representative leak scenarios were selected based on frequency analysis of major accident hazards associated with typical FPSO facility. This study revealed that the overpressure exceedance frequency in plated process deck was higher than the grated process deck for the selected scenario. This serves as quantitative guidance for designers to select an inherently safer type of decks in FPSOs from explosion perspective during the preliminary design stage. However, a detailed Computational Fluid Dynamics (CFD) study is recommended to get an insight of dangers associated with the presence of plated and grated process decks in FPSO, by considering all the parameters and conditions applicable.

Vapor cloud explosion is one of the major threats to Floating, Production, Storage and Offloading (FPSO) facilities due to its congested and confined nature. Reduction in explosion overpressure can be achieved by improving the ventilation in FPSO. During early design stage of FPSO, designers consider providing grated process decks to improve the ventilation. However, there is limited research on the comparison of the explosion overpressure between the grated deck and the traditional plated deck. In this study, Vapor Cloud Explosion perspective of plated versus grated process deck in typical FPSO was evaluated by utilizing Det Norske Veritas’s (DNV) SAFETI OFFSHORE modelling tool. Representative leak scenarios were selected based on frequency analysis of major accident hazards associated with typical FPSO facility. This study revealed that the overpressure exceedance frequency in plated process deck was higher than the grated process deck for the selected scenario. This serves as quantitative guidance for designers to select an inherently safer type of decks in FPSOs from explosion perspective during the preliminary design stage. However, a detailed Computational Fluid Dynamics (CFD) study is recommended to get an insight of dangers associated with the presence of plated and grated process decks in FPSO, by considering all the parameters and conditions applicable.

This research studied the synthesis of graphite oxide and reduced graphite oxide via a low- cost manufacturing method. The process started with the chemical oxidation of commercial graphite powder into graphite oxide by Staudenmaier's method, followed by the chemical reduction of graphite oxide in ammonium hydroxide vapor. Subsequently, graphite oxide and reduced graphite oxide were assembled into a thin film, and microscale liquid droplets were placed into the film surface for measurement of wettability and contact angle. It is found that a graphite oxide sheet is hydrophilic while a reduced graphite oxide is hydrophobic with a contact angle equal to 120°C and 53°C respectively.

This research studied the synthesis of graphite oxide and reduced graphite oxide via a low- cost manufacturing method. The process started with the chemical oxidation of commercial graphite powder into graphite oxide by Staudenmaier's method, followed by the chemical reduction of graphite oxide in ammonium hydroxide vapor. Subsequently, graphite oxide and reduced graphite oxide were assembled into a thin film, and microscale liquid droplets were placed into the film surface for measurement of wettability and contact angle. It is found that a graphite oxide sheet is hydrophilic while a reduced graphite oxide is hydrophobic with a contact angle equal to 120°C and 53°C respectively.

Bubble column reactor belongs to the general class of multiphase reactors in which gas come in contact with liquid. This reactor purposely used to mix the two phases or substances where the gas is dispersed into the column from the bottom and rises within the liquid and escapses from the upper liquid surface. Throughout the design and development phase, the reactor design specifications were identified to meet the experimental requirements for hydrodynamics study in a bubble column using the high-speed camera, industrial radiotracer, and radioactive particle tracking techniques. This bubble column reactor design comes with six different type of sparger design for various mixing pattern optimization. The design methodology structured as design development process, conceptual design selection process, detailed design specifications, product fabrication, and final product testing. This versatile reactor is developed to overcome the problems faced in understanding hydrodynamics behavior of using different types of sparger design, leading to design optimization for better mixing and blending efficiency in multiphase flow investigations. This study has demonstrated that the newly quadrilateral bubble column reactor is ready to be used for the various types of laboratory assessment including industrial radioactive experiments.

The chemical method is one of the most promising routes for the production of multi-walled carbon nanotubes. In this study, multi-walled carbon nanotubes (MWCNTs) were successfully synthesized by the modified Staudenmaier method. MWCNTs were synthesized using graphite powder at room temperature. This process does not utilize any metal catalyst. The prepared multi-walled carbon nanotubes were characterized for their crystalline, structural and thermal stability properties. The structural, crystalline and morphological characterization of The produced MWCNTs were performed by using scanning electron microscopy(SEM), transmission electron microscopy(TEM), X-ray diffraction (XRD), thermogravimetric analysis(TGA), Raman analysis, and atomic force microscopy( AFM). Crystallinity and graphitization degree was observed for the produced MWCNTs have a diameter of 13.1 nm. The yield is approximately 10% of the carbon source (graphite). Moreover, the obtained MWCNTs have high thermal stability and oxidation resistance lower than 401.80 °C. The present approach provides a simple low cost and easy method of MWCNTs synthesis.

In this work, we have quantified the influence of superficial gas velocity and sparger design on bubble size, gas hold-up, and bubble rise velocity in quadrilateral bubble column test rig (0.2 x 0.2 m in cross-section and 2 m in height). Six sparger designs were used to generate homogeneous to heterogeneous flow regime for the investigation of the effect of superficial gas velocity and sparger design on gas holdup and bubble size distribution in a bubble column. This study has proved that the air distributor optimization can be recognized using high-speed camera technique. The size of bubbles inside the column is also affected by the size of orifice diameter and number of holes of the sparger. This study concludes that Sparger C and Sparger D design with orifice size 0.5 mm may use optimum gas flow rate to generate homogeneous bubbly flow with higher gas hold-up for better mixing process in this bubble column reactor. At heterogeneous flow regime, it was observed that the sparger orifice diameter shown little impact on the column behavior. The experimental results also can subsequently be applied to the development and validation of the proper mathematical model.

Bubble column reactor belongs to the general class of multiphase reactors in which gas come in contact with liquid. This reactor purposely used to mix the two phases or substances where the gas is dispersed into the column from the bottom and rises within the liquid and escapses from the upper liquid surface. Throughout the design and development phase, the reactor design specifications were identified to meet the experimental requirements for hydrodynamics study in a bubble column using the high-speed camera, industrial radiotracer, and radioactive particle tracking techniques. This bubble column reactor design comes with six different type of sparger design for various mixing pattern optimization. The design methodology structured as design development process, conceptual design selection process, detailed design specifications, product fabrication, and final product testing. This versatile reactor is developed to overcome the problems faced in understanding hydrodynamics behavior of using different types of sparger design, leading to design optimization for better mixing and blending efficiency in multiphase flow investigations. This study has demonstrated that the newly quadrilateral bubble column reactor is ready to be used for the various types of laboratory assessment including industrial radioactive experiments.

Bubble column reactor belongs to the general class of multiphase reactors in which gas come in contact with liquid. This reactor purposely used to mix the two phases or substances where the gas is dispersed into the column from the bottom and rises within the liquid and escapses from the upper liquid surface. Throughout the design and development phase, the reactor design specifications were identified to meet the experimental requirements for hydrodynamics study in a bubble column using the high-speed camera, industrial radiotracer, and radioactive particle tracking techniques. This bubble column reactor design comes with six different type of sparger design for various mixing pattern optimization. The design methodology structured as design development process, conceptual design selection process, detailed design specifications, product fabrication, and final product testing. This versatile reactor is developed to overcome the problems faced in understanding hydrodynamics behavior of using different types of sparger design, leading to design optimization for better mixing and blending efficiency in multiphase flow investigations. This study has demonstrated that the newly quadrilateral bubble column reactor is ready to be used for the various types of laboratory assessment including industrial radioactive experiments.

In this work, we have quantified the influence of superficial gas velocity and sparger design on bubble size, gas hold-up, and bubble rise velocity in quadrilateral bubble column test rig (0.2 x 0.2 m in cross-section and 2 m in height). Six sparger designs were used to generate homogeneous to heterogeneous flow regime for the investigation of the effect of superficial gas velocity and sparger design on gas holdup and bubble size distribution in a bubble column. This study has proved that the air distributor optimization can be recognized using high-speed camera technique. The size of bubbles inside the column is also affected by the size of orifice diameter and number of holes of the sparger. This study concludes that Sparger C and Sparger D design with orifice size 0.5 mm may use optimum gas flow rate to generate homogeneous bubbly flow with higher gas hold-up for better mixing process in this bubble column reactor. At heterogeneous flow regime, it was observed that the sparger orifice diameter shown little impact on the column behavior. The experimental results also can subsequently be applied to the development and validation of the proper mathematical model.

Bubble column reactor belongs to the general class of multiphase reactors in which gas come in contact with liquid. This reactor purposely used to mix the two phases or substances where the gas is dispersed into the column from the bottom and rises within the liquid and escapses from the upper liquid surface. Throughout the design and development phase, the reactor design specifications were identified to meet the experimental requirements for hydrodynamics study in a bubble column using the high-speed camera, industrial radiotracer, and radioactive particle tracking techniques. This bubble column reactor design comes with six different type of sparger design for various mixing pattern optimization. The design methodology structured as design development process, conceptual design selection process, detailed design specifications, product fabrication, and final product testing. This versatile reactor is developed to overcome the problems faced in understanding hydrodynamics behavior of using different types of sparger design, leading to design optimization for better mixing and blending efficiency in multiphase flow investigations. This study has demonstrated that the newly quadrilateral bubble column reactor is ready to be used for the various types of laboratory assessment including industrial radioactive experiments.

The chemical method is one of the most promising routes for the production of multi-walled carbon nanotubes. In this study, multi-walled carbon nanotubes (MWCNTs) were successfully synthesized by the modified Staudenmaier method. MWCNTs were synthesized using graphite powder at room temperature. This process does not utilize any metal catalyst. The prepared multi-walled carbon nanotubes were characterized for their crystalline, structural and thermal stability properties. The structural, crystalline and morphological characterization of The produced MWCNTs were performed by using scanning electron microscopy(SEM), transmission electron microscopy(TEM), X-ray diffraction (XRD), thermogravimetric analysis(TGA), Raman analysis, and atomic force microscopy( AFM). Crystallinity and graphitization degree was observed for the produced MWCNTs have a diameter of 13.1 nm. The yield is approximately 10% of the carbon source (graphite). Moreover, the obtained MWCNTs have high thermal stability and oxidation resistance lower than 401.80 °C. The present approach provides a simple low cost and easy method of MWCNTs synthesis.

Radioisotope techniques are constantly and extensively used all over the world as a method to identify process systems malfunctions in various industries without requiring the shut down of the processing plant thus leading to high economical benefits to the plant owner. Different aspects of industrial radiotracer technology for troubleshooting, process control and optimization are evaluated through an exhaustive literature survey. The review covers the advantages of radiotracers, most commonly used radiotracers in industry for specific studies, applications of radiotracer techniques in various chemical industries, the design of radiotracer technology experiments, radiation detection and data acquisition in radiotracer technology as well as radiological safety aspects. Two industrial radiotracer techniques of residence time distribution (RTD) measurements and radioactive particle tracking (RPT) are discussed. The design of radiotracer technology experiments are also divided into two categories-radioactive particle tracking applications and residence time distribution applications.

The effect of heat treatment on the microstructure, hardness and density of sintered (1129°C, 45 min) specimens of iron-base powder alloys containing 0.8 – 2.5% C, 2% Cu and additives of chromium- and molybdenum-alloyed Astaloy E iron powder is studied.

The nanomechanical properties of carbon nanotubes particulate-reinforced aluminum matrix nanocomposites (Al-CNTs) have been characterized using nanoindentation. Bulk nanocomposite specimens containing 2 wt % multiwalled CNTs (MWCNTs) were synthesized by a combination of ball milling and powder metallurgy route. It has been tried to understand the correlation between microstructural evolution particularly carbon nanotubes (CNTs) dispersion during milling and mechanical properties of Al-2 wt % nanocomposites. Maximum enhancement of +23% and +44% has been found in Young’s modulus and hardness respectively, owing to well homogenous dispersion of CNTs within the aluminum matrix at longer milling time.

This study aimed to investigate the effect of gamma radiation on epoxidized natural rubber latex (ENRL) with the presence of sensitizer, with regards to its tensile properties, gel fraction and thermal stability. ENRL used are ENRL-25 and ENRL-50, with epoxidation level of 25 mole% and 50 mole% respectively. The sensitizers, i.e. butyl acrylate, 1, 6-hexanediol diacrylate and trimethylolpropane triacrylate, at the range of 0.5 to 3 phr, were added to ENRL together with potassium laurate, stirred and irradiated with gamma radiation at 12 kGy. Cast films were prepared from the irradiated ENRL and used in tensile test, gel fraction and thermogravimetry analysis. Results revealed that the presence of sensitizer during gamma irradiation of ENRL enhanced the tensile properties, gel fraction and thermal stability of ENRL. The effects of sensitizer depended on number of acrylate groups in the sensitizer and epoxidation level of the ENRL. Amount of sensitizer beyond 0.5 phr was found to adversely affect the tensile strength of gamma irradiated ENRL at 12 kGy.

The effect of heat treatment on the microstructure, hardness and density of sintered (1129°C, 45 min) specimens of iron-base powder alloys containing 0.8 – 2.5% C, 2% Cu and additives of chromium- and molybdenum-alloyed Astaloy E iron powder is studied.

This study aimed to investigate the effect of gamma radiation on epoxidized natural rubber latex (ENRL) with the presence of sensitizer, with regards to its tensile properties, gel fraction and thermal stability. ENRL used are ENRL-25 and ENRL-50, with epoxidation level of 25 mole% and 50 mole% respectively. The sensitizers, i.e. butyl acrylate, 1, 6-hexanediol diacrylate and trimethylolpropane triacrylate, at the range of 0.5 to 3 phr, were added to ENRL together with potassium laurate, stirred and irradiated with gamma radiation at 12 kGy. Cast films were prepared from the irradiated ENRL and used in tensile test, gel fraction and thermogravimetry analysis. Results revealed that the presence of sensitizer during gamma irradiation of ENRL enhanced the tensile properties, gel fraction and thermal stability of ENRL. The effects of sensitizer depended on number of acrylate groups in the sensitizer and epoxidation level of the ENRL. Amount of sensitizer beyond 0.5 phr was found to adversely affect the tensile strength of gamma irradiated ENRL at 12 kGy.

The nanomechanical properties of carbon nanotubes particulate-reinforced aluminum matrix nanocomposites (Al-CNTs) have been characterized using nanoindentation. Bulk nanocomposite specimens containing 2 wt % multiwalled CNTs (MWCNTs) were synthesized by a combination of ball milling and powder metallurgy route. It has been tried to understand the correlation between microstructural evolution particularly carbon nanotubes (CNTs) dispersion during milling and mechanical properties of Al-2 wt % nanocomposites. Maximum enhancement of +23% and +44% has been found in Young’s modulus and hardness respectively, owing to well homogenous dispersion of CNTs within the aluminum matrix at longer milling time.

Radioisotope techniques are constantly and extensively used all over the world as a method to identify process systems malfunctions in various industries without requiring the shut down of the processing plant thus leading to high economical benefits to the plant owner. Different aspects of industrial radiotracer technology for troubleshooting, process control and optimization are evaluated through an exhaustive literature survey. The review covers the advantages of radiotracers, most commonly used radiotracers in industry for specific studies, applications of radiotracer techniques in various chemical industries, the design of radiotracer technology experiments, radiation detection and data acquisition in radiotracer technology as well as radiological safety aspects. Two industrial radiotracer techniques of residence time distribution (RTD) measurements and radioactive particle tracking (RPT) are discussed. The design of radiotracer technology experiments are also divided into two categories-radioactive particle tracking applications and residence time distribution applications.

Condensed aerosol fire extinguishing technology is relatively a new fire suppression technology in fire extinguishing research and industry. In current market, almost all condensed aerosol forming agents contain potassium nitrate or perchlorate as an oxidant which generates corrosive potassium oxides and salts after agent combustion. In this research, copper metal plate is found to be very vulnerable to corrosions caused by potassium compounds and contents of potassium based oxidants and corrosion potentials of four commercialized aerosol forming agents were analyzed. The four aerosol forming agents have similar contents of potassium based oxidants and their corrosion potential after combustion and discharge should be close to each other. Besides corrosion study of different K-type aerosol on metal plates, Computer Fluid Dynamic (CFD) modeling of aerosol motion during and after discharging in a large confined room was carried out. Higher aerosol discharging velocity and specifically directional arrangement of canisters help the distribution of aerosol momentum, which is beneficial to the increase of fire extinguishing efficiency and fewer aerosol forming agents are needed if fire extinguishing efficiency per agent is elevated. Fires which are shed or covered by objects in a compartment are hard to be extinguished and aerosol of high momentum is required for extinguishing fires under covers. It is the first time that computer fluid dynamics modeling was applied for pyrotechnic aerosol fire extinguishing study. Reynolds Averaged Navier Strokes equations and discrete finite volume method was used for treating the turbulent aerosol and fire.

Condensed aerosol fire extinguishing technology is relatively a new fire suppression technology in fire extinguishing research and industry. In current market, almost all condensed aerosol forming agents contain potassium nitrate or perchlorate as an oxidant which generates corrosive potassium oxides and salts after agent combustion. In this research, copper metal plate is found to be very vulnerable to corrosions caused by potassium compounds and contents of potassium based oxidants and corrosion potentials of four commercialized aerosol forming agents were analyzed. The four aerosol forming agents have similar contents of potassium based oxidants and their corrosion potential after combustion and discharge should be close to each other. Besides corrosion study of different K-type aerosol on metal plates, Computer Fluid Dynamic (CFD) modeling of aerosol motion during and after discharging in a large confined room was carried out. Higher aerosol discharging velocity and specifically directional arrangement of canisters help the distribution of aerosol momentum, which is beneficial to the increase of fire extinguishing efficiency and fewer aerosol forming agents are needed if fire extinguishing efficiency per agent is elevated. Fires which are shed or covered by objects in a compartment are hard to be extinguished and aerosol of high momentum is required for extinguishing fires under covers. It is the first time that computer fluid dynamics modeling was applied for pyrotechnic aerosol fire extinguishing study. Reynolds Averaged Navier Strokes equations and discrete finite volume method was used for treating the turbulent aerosol and fire.

The effects of multi-walled carbon nanotubes on the melting temperature and microstructural evolution of the Sn-5Sb/Cu joints with solder formulations (Sn-5Sb-xCNT; 0, 0.01, 0.05 and 0.1 wt.%) was evaluated. The melting temperature results indicate that the presence of carbon nanotubes addition to the solder matrix lead to a marginal decrease in the peak temperature of the composite solders due to high surface free energy of MWCNTs in the solder matrix. More so, solder joints were subjected to both the as-reflow and isothermal aging conditions after which the microstructural evolution in the joints was investigated. From the IMC thickness data retrieved, it was observed that the composite solders showed better results for all subjected conditions as compared with the plain solder and the most appreciable IMC layer suppression was detected across board in the 0.05wt.% CNTs reinforced solder system.

The effects of multi-walled carbon nanotubes on the melting temperature and microstructural evolution of the Sn-5Sb/Cu joints with solder formulations (Sn-5Sb-xCNT; 0, 0.01, 0.05 and 0.1 wt.%) was evaluated. The melting temperature results indicate that the presence of carbon nanotubes addition to the solder matrix lead to a marginal decrease in the peak temperature of the composite solders due to high surface free energy of MWCNTs in the solder matrix. More so, solder joints were subjected to both the as-reflow and isothermal aging conditions after which the microstructural evolution in the joints was investigated. From the IMC thickness data retrieved, it was observed that the composite solders showed better results for all subjected conditions as compared with the plain solder and the most appreciable IMC layer suppression was detected across board in the 0.05wt.% CNTs reinforced solder system.

The occurrence of pattern formation within physical dimension and mechanical property changes was systematically investigated based on the addition of various amounts of pre-alloyed Astaloy E and carbon to iron powder. Powder samples were prepared in a similar manner by mixing in a Y-type mixer, compacting in a floating die under constant pressure and sintering in a hydrogen atmosphere tunnel furnace at 1,120 °C for 45 min. An optical microscope equipped with image analysis was employed to study the microstructure. Physical properties, such as the green density, sintered density and dimensional changes, as well as the hardness were measured. The results indicate that the addition of Astaloy E and carbon results in increased green density, sintered density and hardness. An increase in the carbon content resulted in physical dimension growth of the parts.

This review paper discusses the application of biofilm as an alternative technology for the treatment of wastewater under various loading and operation conditions. In the past few years the biofilm technology has become more common and widely used in the world to meet the requirement for clean water sources of the world’s growing population. Besides, the conventional wastewater treatment plants like activated sludge process present some shortcomings such as not very flexible method (if there is sudden change in the character of sewage and the effluent of bad quality is obtained), so better system is urgently needed to provide additional capacity with the least possible cost and to meet the standard effluent by the local authorities. The increased incoming flow of wastewater to the treatment plants and organic loading always demand for additional treatment capacity. Fundamental research into biofilm is presented in this paper in sections that discuss the use of biofilm whereby a comparison between suspended and fixed film, old and new biofilm are made. Besides, bed types namely moving bed, fixed bed and floating bed, un-submerged fixed film systems of trickling filters and rotating biological contactors are explained. Nutrients removal of nitrogen and phosphorus and nano technology application in biofilm are also explained. Results from investigations of different applications carried out at the laboratory and pilot scales are also discussed.

Radioactive particle tracking (RPT) has emerged as a promising and versatile technique that can provide rich information about a variety of multiphase flow systems. However, RPT is not an off-the-shelf technique, and thus, users must customize RPT for their applications. This paper presents a simple procedure for preparing radioactive tracer particles created via irradiation with neutrons from the TRIGA Mark II research reactor. The present study focuses on the performance evaluation of encapsulated gold and scandium particles for applications as individual radioactive tracer particles using qualitative and quantitative neutron activation analysis (NAA) and an X-ray microcomputed tomography (X-ray Micro-CT) scanner installed at the Malaysian Nuclear Agency.

Owing to the great advancement in technology, the input/output terminals in electronic packaging have greatly increased resulting to a proportional increase in solder interconnection joints of electrical components. Therefore, in order to work in line with the mission and vision of the electronic industries which are the production of more powerful, efficient and miniaturized gadgets, it is imminent to introduce alloying elements to the existing lead free conventional solders which will possibly lead to the enhancement of electrical and mechanical properties of the interconnection joints. An attempt has been made to reveal an element of desirable properties which can meet the demands of the micro systems and electronics industries. A documentation of the benefits that the carbon nanotubes CNTs can yield has been presented in previous studies which therefore serve as the primary reason for embarking on this review report.

Radioactive particle tracking (RPT) has emerged as a promising and versatile technique that can provide rich information about a variety of multiphase flow systems. However, RPT is not an off-the-shelf technique, and thus, users must customize RPT for their applications. This paper presents a simple procedure for preparing radioactive tracer particles created via irradiation with neutrons from the TRIGA Mark II research reactor. The present study focuses on the performance evaluation of encapsulated gold and scandium particles for applications as individual radioactive tracer particles using qualitative and quantitative neutron activation analysis (NAA) and an X-ray microcomputed tomography (X-ray Micro-CT) scanner installed at the Malaysian Nuclear Agency.

The occurrence of pattern formation within physical dimension and mechanical property changes was systematically investigated based on the addition of various amounts of pre-alloyed Astaloy E and carbon to iron powder. Powder samples were prepared in a similar manner by mixing in a Y-type mixer, compacting in a floating die under constant pressure and sintering in a hydrogen atmosphere tunnel furnace at 1,120 °C for 45 min. An optical microscope equipped with image analysis was employed to study the microstructure. Physical properties, such as the green density, sintered density and dimensional changes, as well as the hardness were measured. The results indicate that the addition of Astaloy E and carbon results in increased green density, sintered density and hardness. An increase in the carbon content resulted in physical dimension growth of the parts.

This review paper discusses the application of biofilm as an alternative technology for the treatment of wastewater under various loading and operation conditions. In the past few years the biofilm technology has become more common and widely used in the world to meet the requirement for clean water sources of the world’s growing population. Besides, the conventional wastewater treatment plants like activated sludge process present some shortcomings such as not very flexible method (if there is sudden change in the character of sewage and the effluent of bad quality is obtained), so better system is urgently needed to provide additional capacity with the least possible cost and to meet the standard effluent by the local authorities. The increased incoming flow of wastewater to the treatment plants and organic loading always demand for additional treatment capacity. Fundamental research into biofilm is presented in this paper in sections that discuss the use of biofilm whereby a comparison between suspended and fixed film, old and new biofilm are made. Besides, bed types namely moving bed, fixed bed and floating bed, un-submerged fixed film systems of trickling filters and rotating biological contactors are explained. Nutrients removal of nitrogen and phosphorus and nano technology application in biofilm are also explained. Results from investigations of different applications carried out at the laboratory and pilot scales are also discussed.

Owing to the great advancement in technology, the input/output terminals in electronic packaging have greatly increased resulting to a proportional increase in solder interconnection joints of electrical components. Therefore, in order to work in line with the mission and vision of the electronic industries which are the production of more powerful, efficient and miniaturized gadgets, it is imminent to introduce alloying elements to the existing lead free conventional solders which will possibly lead to the enhancement of electrical and mechanical properties of the interconnection joints. An attempt has been made to reveal an element of desirable properties which can meet the demands of the micro systems and electronics industries. A documentation of the benefits that the carbon nanotubes CNTs can yield has been presented in previous studies which therefore serve as the primary reason for embarking on this review report.

Thirty Boer and 30 Cyprus Shami goats were measured for their body weights, height at withers, body length and heart girth. Each breed was divided into three age groups: group 1 (6-12 months old), group 2 (12-18 months old) and group 3 (more than 18 months old). Means for linear body measurements according to age groups were compared between Shami and Boer goats. There was a highly significant differences (p<0.005) between Boer and Cyprus Shami goats in term of each body measurement and body weight. In the present study, to predict the body weight of Cyprus Shami goat, the combination of three parameters of linear body conformation can be used.

Thirty Boer and 30 Cyprus Shami goats were measured for their body weights, height at withers, body length and heart girth. Each breed was divided into three age groups: group 1 (6-12 months old), group 2 (12-18 months old) and group 3 (more than 18 months old). Means for linear body measurements according to age groups were compared between Shami and Boer goats. There was a highly significant differences (p<0.005) between Boer and Cyprus Shami goats in term of each body measurement and body weight. In the present study, to predict the body weight of Cyprus Shami goat, the combination of three parameters of linear body conformation can be used.

A biochar produced from empty fruit bunches (EFB) was gasified in a fluidized bed using air to determine gas yield, overall carbon conversion, gas quality, and composition as a function of temperature. The experiment was conducted in the temperature range of 500–850 °C. It was observed that biochar has the potential to replace coal as a gasification agent in power plants. Hydrogen gas from biochar was also optimized during the experiment. High temperatures favor H2 and CO formation. There was an increase of H2 over the temperature range from 500–850 °C from 5.53% to 27.97% (v/v), with a heating value of 30 kJ/g. The C conversion in the same temperature range increased from 76% to 84%. Therefore, there are great prospects for the use of biochar from EFB as an alternative fuel in power plants, as a renewable energy providing an alternative path to biofuels. Results from this work enable us to better understand syn gas production under high treatment temperatures.

A biochar produced from empty fruit bunches (EFB) was gasified in a fluidized bed using air to determine gas yield, overall carbon conversion, gas quality, and composition as a function of temperature. The experiment was conducted in the temperature range of 500–850 °C. It was observed that biochar has the potential to replace coal as a gasification agent in power plants. Hydrogen gas from biochar was also optimized during the experiment. High temperatures favor H2 and CO formation. There was an increase of H2 over the temperature range from 500–850 °C from 5.53% to 27.97% (v/v), with a heating value of 30 kJ/g. The C conversion in the same temperature range increased from 76% to 84%. Therefore, there are great prospects for the use of biochar from EFB as an alternative fuel in power plants, as a renewable energy providing an alternative path to biofuels. Results from this work enable us to better understand syn gas production under high treatment temperatures.