Ahmad Sanadi - Academia.edu (original) (raw)

Papers by Ahmad Sanadi

Applied Radiation and Isotopes, 2010

The studies of 137 Cs and 239 + 240 Pu distributions in surface seawater at South China Sea withi... more The studies of 137 Cs and 239 + 240 Pu distributions in surface seawater at South China Sea within the Exclusive Economic Zone (EEZ) of Peninsular Malaysia were carried out in June 2008. The analysis results will serve as additional information to the expanded baseline data for Malaysia's marine environment. Thirty locations from extended study area were identified in the EEZ from which large volumes of surface seawater samples were collected. Different co-precipitation techniques were employed to concentrate cesium and plutonium separately. A known amount of 134 Cs and 242 Pu tracers were used as yield determinant. The precipitate slurry was collected and oven dried at 60 o C for 1-2 days. Cesium precipitate was fine-ground and counted using gamma-ray spectrometry system at 661.62 keV, while plutonium was separated from other radionuclides using anion exchange, electrodeposited and counted using alpha spectrometry. The activity concentrations of 137 Cs and 239 + 240 Pu were in the range of 3.40-5.89 Bq/m 3 and 2.3-7.9 mBq/m 3 , respectively. The 239 + 240 Pu/ 137 Cs ratios indicate that there are no new inputs of these radionuclides into the area.

ACTIVITIES CONCENTRATION OF 239+240Pu IN SEDIMENT IN SABAH AND SARAWAK COASTAL AREA

ABSTRACT

Improved in-house method to determine Pu-239+240 in sediments

Preservation and conservation are emerging as an important area of research and education for lib... more Preservation and conservation are emerging as an important area of research and education for library and information science. School of Library and Information Science worldwide are presently aware of the need to develop curriculum in this growing area of research and practice. Millions of dollars have been invested in preservation and conservation research since the early 1990s including research on how digital preservation can aid education but there has been no parallel investment to support teaching and learning about preservation and conservation. Without investment in education related to preservation and conservation, we face a future in which the problems of degradation of our cultural heritage will be more striking. There was a study done in the West that concluded that there is an urgent need for development of preservation and conservation education programmes worldwide amidst a burgeoning growth of digital library research and practice by librarians. While many LIS schools in western countries have developed preservation and conservation courses such as at School of Information, University of Texas, Austin, the state of education in preservation and conservation in the Muslim World is unknown. Therefore, it is the aim of the proposed paper that a survey on the preservation and conservation programme in the Muslim World be conducted.

Methadone maintenance therapy (MMT) has been used for opioid dependence as one of the harm-reduct... more Methadone maintenance therapy (MMT) has been used for opioid dependence as one of the harm-reduction approaches. It is also effectiveindirectlyto prevent the wide spread of HIVrelated risks such as needle sharing behaviour and illicit drug use. With low costs calculated per patient, MMT has been put as top priorities on reducing opioid dependencies in Malaysia. However, the effective dose strategy of the therapy is still open to debate. The study aimed to investigate the potential of methadone trough concentration (C trough)tobe a surrogate marker for such purpose. We conducted a 9-months prospective study to assess the relationship between C trough and Dose (D) of methadone. A total of 115 subjects fulfilled the inclusion criteria and had given their consents to participate. Two (2) ml of the trough blood samples (C trough) were taken and centrifuged within 4 hours from the time taken at 5,000 Gfor 5 minutes. The resulting serum samples were kept at-20°C until further analysis. The methadone concentration was determined by using a validated method for Methadone ELISA kit. The patients were subjected to another 2 follow ups at 3 months interval each and the same method of serum sampling was applied. Initial correlation reveals significant positive correlation between the two variables in every follow up, ranging between r=0.403-0.419 (p<0.005). Further regression analysis reveals that the coefficient of determination, r 2 was poor with only 15-17% of variation in the C trough can be explained by the changes in clinical doses (p<0.005). Based on the results, we conclude that daily clinical dose poorly predicts methadone C trough for the purpose of dosing adjustment and monitoring of therapy.

Library Philosophy and Practice, 2011

Distribution of 239+240 Pu in Sediments of the West Coast of Peninsular Malaysia

ABSTRACT

DISTRIBUTION OF LEAD, 210Pb IN KUALA MUDA SEDIMENT

ABSTRACT

BioMed Research International, 2013

The potential of three submerged aquatic plant species (Cabomba piauhyensis, Egeria densa, andHyd... more The potential of three submerged aquatic plant species (Cabomba piauhyensis, Egeria densa, andHydrilla verticillata) to be used for As, Al, and Zn phytoremediation was tested. The plants were exposed for 14 days under hydroponic conditions to mine waste water effluents in order to assess the suitability of the aquatic plants to remediate elevated multi-metals concentrations in mine waste water. The results show that theE. densaandH. verticillataare able to accumulate high amount of arsenic (95.2%) and zinc (93.7%) and resulted in a decrease of arsenic and zinc in the ambient water. On the other hand,C. piauhyensisshows remarkable aluminium accumulation in plant biomass (83.8%) compared to the other tested plants. The ability of these plants to accumulate the studied metals and survive throughout the experiment demonstrates the potential of these plants to remediate metal enriched water especially for mine drainage effluent. Among the three tested aquatic plants,H. verticillatawas fo...

Applied Surface Science, 2014

ITO-based transparent conductive electrodes (TCE) with Ag/Ni thin metal under-layer were deposite... more ITO-based transparent conductive electrodes (TCE) with Ag/Ni thin metal under-layer were deposited on Si and glass substrates by thermal evaporator and RF magnetron sputtering system. Ceramic ITO with purity of 99.99% and In 2 O 3 :SnO 2 weight ratio of 90:10 was used as a target at room temperature. Post-deposition annealing was performed on the TCE at moderate temperature of 500 • C, 600 • C and 700 • C under N 2 ambient. It was observed that the structural properties, optical transmittance, electrical characteristics and surface morphology were improved significantly after the post-annealing process. Post-annealed ITO/Ag/Ni at 600 • C shows the best quality of TCE with figure-of-merit (FOM) of 1.5 × 10 −2 −1 and high optical transmittance of 83% at 470 nm as well as very low electrical resistivity of 4.3 × 10 −5-cm. The crystalline quality and surface morphological plays an important role in determining the quality of the TCE multilayer thin films properties.

Various tools have been employed to help detect counterproductive behaviors including the use of ... more Various tools have been employed to help detect counterproductive behaviors including the use of polygraph techniques. The purpose of this paper is to study, design and develop a proof-of-concept polygraphic counterproductive behavior index profiling system ...

Journal of Radioanalytical and Nuclear Chemistry, 2010

The present distributions of 239?240 Pu, 241 Am and activity ratio of 241 Am/ 239?240 Pu in surfa... more The present distributions of 239?240 Pu, 241 Am and activity ratio of 241 Am/ 239?240 Pu in surface seawater of the Peninsular Malaysia east coast were studied. The surface seawater samples were collected at 30 identified stations during the expedition conducted in 2008. 239?240 Pu activity concentrations in surface seawater of the studied area were in the range of 2.33 ± 0.20-7.95 ± 0.68 mBq/m 3 , meanwhile 241 Am activity concentrations ranged from MDA to 1.90 ± 0.23 mBq/m 3. The calculated activity ratios of 241 Am/ 239?240 Pu were varied and disperse distributed with the ranged of 0.12-0.53. The relationships between anthropogenic radionuclide and oceanographic parameters such as turbidity and salinity were examined. The linearly relationships between 239?240 Pu and oceanographic parameters are important for better understanding of its transport processes and behavior in the east coast of Peninsular Malaysia marine environment. Thus, the differ of distribution of 239?240 Pu, 241 Am and 241 Am/ 239?240 Pu in the studied area mainly due to high affinity of 239?240 Pu to associate with sinking particles, mobility nature of 241 Am, degree of particle reactive of both anthropogenic radionuclides, scavenging and removal process; and others.

A sampling expedition into the East Coast Peninsula Malaysia Exclusive Economic Zone (EEZ) was ca... more A sampling expedition into the East Coast Peninsula Malaysia Exclusive Economic Zone (EEZ) was carried in June 2008. Marine surface sediment samples were collected and the activity concentrations of 210 Pb have been determined. Its distribution was plotted and the findings show that the activity concentrations decline from north to south. On the other hand, the activity concentrations are increasing from west to east right to the edge of the EEZ. The 210 Pb activity concentrations were found to be in the range of 18.3 – 123.1 Bq/kg.

Surface soils of 2 cm depth were sampled at developed and undeveloped areas in Fraser's Hill, Pah... more Surface soils of 2 cm depth were sampled at developed and undeveloped areas in Fraser's Hill, Pahang, Malaysia. Thirty one (31) locations were collected and 226 Ra, 232 Th and 40 K activity concentrations were measured using HPGe Gamma Counting System. The mean radium equivalent activity concentration (Ra eq) for the sampled area was 463.37 Bq/kg. The Undeveloped area was found to have higher mean of Ra eq compared to Developed area. The mean Ra eq for each area was found to be 614.07 Bq/kg and 354.53 Bq/kg respectively. The external hazard index (H ex) were calculated and found to have a mean of 1.251. Undeveloped area was found to have higher mean of 1.658 compared to developed area with a mean of 0.957. Many locations were found to have H ex higher than 1.000.

Caesium-137 (137 Cs) in an anthropogenic radionuclide originated from the fission of fissile mate... more Caesium-137 (137 Cs) in an anthropogenic radionuclide originated from the fission of fissile materials. Nuclear weapons testing during the 1960s and the Chernobyl disaster introduced substantial amount of 137 Cs into the atmosphere that are then eventually deposited back to earth's surface. Caesium-137 can be used as tracer to study soil movements since it adsorbs to soil particles. This paper aims to describe the distribution of 137 Cs in surface soil of Fraser's Hill, Pahang, determine the levels of 137 Cs here compared to other areas, and to check correlation of 137 Cs levels to physical data. A series of sampling were carried out between February 2014 and August 2015. Soil samples were taken from 31 locations using soil scraper. The samples were then taken to the laboratory to be dried, homogenized, grinded and sieved. The activity concentration of 137 Cs in the samples was determined using gamma spectroscopy. The activity concentration was found to be between 0.26 Bq/kg and 5.14 Bq/kg. Although this paper only studies surface soil, 137 Cs is expected to be present within the soil body. Further study of 137 Cs in the soil body can be used to predictive model for soil erosion.

Journal of …, 2011

Large volumes of surface seawater samples were collected from thirty locations in the Exclusive E... more Large volumes of surface seawater samples were collected from thirty locations in the Exclusive Economic Zone (EEZ) of the east coast Peninsular Malaysia on June 2008 to study the activity concentrations of 137 Cs. The results will serve as additional information to the existing baseline data and is very useful for monitoring fresh input of anthropogenic radionuclide into Malaysian marine environment. In this study, the activity concentrations of 137 Cs were determined using co-precipitation technique, followed by Gamma Spectrometry measurement. The mean activity concentration of 137 Cs ranged between 3.40 and 5.89 Bq/m 3. Higher activity concentrations were observed at the coastal and towards the south of Peninsular Malaysia and were aligned with the high turbidity. These may due to the rapid diffusion of 137 Cs from suspended particulates and fine sediments into surface seawater. The activity concentrations of 137 Cs observed in this study were slightly higher than the concentrations reported in seawater at the Straits of Malacca, Vietnam and Philippines. This might be because the study area received more input of 137 Cs that originated from global fallout and then deposited on land which later being transported subsequently into the coastal zone due to siltation and erosion processes. It could also be attributed to the intrusion of river waters containing higher concentrations of 137 Cs.

Applied Radiation and Isotopes, 2010

The studies of 137 Cs and 239 + 240 Pu distributions in surface seawater at South China Sea withi... more The studies of 137 Cs and 239 + 240 Pu distributions in surface seawater at South China Sea within the Exclusive Economic Zone (EEZ) of Peninsular Malaysia were carried out in June 2008. The analysis results will serve as additional information to the expanded baseline data for Malaysia's marine environment. Thirty locations from extended study area were identified in the EEZ from which large volumes of surface seawater samples were collected. Different co-precipitation techniques were employed to concentrate cesium and plutonium separately. A known amount of 134 Cs and 242 Pu tracers were used as yield determinant. The precipitate slurry was collected and oven dried at 60 o C for 1-2 days. Cesium precipitate was fine-ground and counted using gamma-ray spectrometry system at 661.62 keV, while plutonium was separated from other radionuclides using anion exchange, electrodeposited and counted using alpha spectrometry. The activity concentrations of 137 Cs and 239 + 240 Pu were in the range of 3.40-5.89 Bq/m 3 and 2.3-7.9 mBq/m 3 , respectively. The 239 + 240 Pu/ 137 Cs ratios indicate that there are no new inputs of these radionuclides into the area.

ACTIVITIES CONCENTRATION OF 239+240Pu IN SEDIMENT IN SABAH AND SARAWAK COASTAL AREA

ABSTRACT

Improved in-house method to determine Pu-239+240 in sediments

Preservation and conservation are emerging as an important area of research and education for lib... more Preservation and conservation are emerging as an important area of research and education for library and information science. School of Library and Information Science worldwide are presently aware of the need to develop curriculum in this growing area of research and practice. Millions of dollars have been invested in preservation and conservation research since the early 1990s including research on how digital preservation can aid education but there has been no parallel investment to support teaching and learning about preservation and conservation. Without investment in education related to preservation and conservation, we face a future in which the problems of degradation of our cultural heritage will be more striking. There was a study done in the West that concluded that there is an urgent need for development of preservation and conservation education programmes worldwide amidst a burgeoning growth of digital library research and practice by librarians. While many LIS schools in western countries have developed preservation and conservation courses such as at School of Information, University of Texas, Austin, the state of education in preservation and conservation in the Muslim World is unknown. Therefore, it is the aim of the proposed paper that a survey on the preservation and conservation programme in the Muslim World be conducted.

Methadone maintenance therapy (MMT) has been used for opioid dependence as one of the harm-reduct... more Methadone maintenance therapy (MMT) has been used for opioid dependence as one of the harm-reduction approaches. It is also effectiveindirectlyto prevent the wide spread of HIVrelated risks such as needle sharing behaviour and illicit drug use. With low costs calculated per patient, MMT has been put as top priorities on reducing opioid dependencies in Malaysia. However, the effective dose strategy of the therapy is still open to debate. The study aimed to investigate the potential of methadone trough concentration (C trough)tobe a surrogate marker for such purpose. We conducted a 9-months prospective study to assess the relationship between C trough and Dose (D) of methadone. A total of 115 subjects fulfilled the inclusion criteria and had given their consents to participate. Two (2) ml of the trough blood samples (C trough) were taken and centrifuged within 4 hours from the time taken at 5,000 Gfor 5 minutes. The resulting serum samples were kept at-20°C until further analysis. The methadone concentration was determined by using a validated method for Methadone ELISA kit. The patients were subjected to another 2 follow ups at 3 months interval each and the same method of serum sampling was applied. Initial correlation reveals significant positive correlation between the two variables in every follow up, ranging between r=0.403-0.419 (p<0.005). Further regression analysis reveals that the coefficient of determination, r 2 was poor with only 15-17% of variation in the C trough can be explained by the changes in clinical doses (p<0.005). Based on the results, we conclude that daily clinical dose poorly predicts methadone C trough for the purpose of dosing adjustment and monitoring of therapy.

Library Philosophy and Practice, 2011

Distribution of 239+240 Pu in Sediments of the West Coast of Peninsular Malaysia

ABSTRACT

DISTRIBUTION OF LEAD, 210Pb IN KUALA MUDA SEDIMENT

ABSTRACT

BioMed Research International, 2013

The potential of three submerged aquatic plant species (Cabomba piauhyensis, Egeria densa, andHyd... more The potential of three submerged aquatic plant species (Cabomba piauhyensis, Egeria densa, andHydrilla verticillata) to be used for As, Al, and Zn phytoremediation was tested. The plants were exposed for 14 days under hydroponic conditions to mine waste water effluents in order to assess the suitability of the aquatic plants to remediate elevated multi-metals concentrations in mine waste water. The results show that theE. densaandH. verticillataare able to accumulate high amount of arsenic (95.2%) and zinc (93.7%) and resulted in a decrease of arsenic and zinc in the ambient water. On the other hand,C. piauhyensisshows remarkable aluminium accumulation in plant biomass (83.8%) compared to the other tested plants. The ability of these plants to accumulate the studied metals and survive throughout the experiment demonstrates the potential of these plants to remediate metal enriched water especially for mine drainage effluent. Among the three tested aquatic plants,H. verticillatawas fo...

Applied Surface Science, 2014

ITO-based transparent conductive electrodes (TCE) with Ag/Ni thin metal under-layer were deposite... more ITO-based transparent conductive electrodes (TCE) with Ag/Ni thin metal under-layer were deposited on Si and glass substrates by thermal evaporator and RF magnetron sputtering system. Ceramic ITO with purity of 99.99% and In 2 O 3 :SnO 2 weight ratio of 90:10 was used as a target at room temperature. Post-deposition annealing was performed on the TCE at moderate temperature of 500 • C, 600 • C and 700 • C under N 2 ambient. It was observed that the structural properties, optical transmittance, electrical characteristics and surface morphology were improved significantly after the post-annealing process. Post-annealed ITO/Ag/Ni at 600 • C shows the best quality of TCE with figure-of-merit (FOM) of 1.5 × 10 −2 −1 and high optical transmittance of 83% at 470 nm as well as very low electrical resistivity of 4.3 × 10 −5-cm. The crystalline quality and surface morphological plays an important role in determining the quality of the TCE multilayer thin films properties.

Various tools have been employed to help detect counterproductive behaviors including the use of ... more Various tools have been employed to help detect counterproductive behaviors including the use of polygraph techniques. The purpose of this paper is to study, design and develop a proof-of-concept polygraphic counterproductive behavior index profiling system ...

Journal of Radioanalytical and Nuclear Chemistry, 2010

The present distributions of 239?240 Pu, 241 Am and activity ratio of 241 Am/ 239?240 Pu in surfa... more The present distributions of 239?240 Pu, 241 Am and activity ratio of 241 Am/ 239?240 Pu in surface seawater of the Peninsular Malaysia east coast were studied. The surface seawater samples were collected at 30 identified stations during the expedition conducted in 2008. 239?240 Pu activity concentrations in surface seawater of the studied area were in the range of 2.33 ± 0.20-7.95 ± 0.68 mBq/m 3 , meanwhile 241 Am activity concentrations ranged from MDA to 1.90 ± 0.23 mBq/m 3. The calculated activity ratios of 241 Am/ 239?240 Pu were varied and disperse distributed with the ranged of 0.12-0.53. The relationships between anthropogenic radionuclide and oceanographic parameters such as turbidity and salinity were examined. The linearly relationships between 239?240 Pu and oceanographic parameters are important for better understanding of its transport processes and behavior in the east coast of Peninsular Malaysia marine environment. Thus, the differ of distribution of 239?240 Pu, 241 Am and 241 Am/ 239?240 Pu in the studied area mainly due to high affinity of 239?240 Pu to associate with sinking particles, mobility nature of 241 Am, degree of particle reactive of both anthropogenic radionuclides, scavenging and removal process; and others.

A sampling expedition into the East Coast Peninsula Malaysia Exclusive Economic Zone (EEZ) was ca... more A sampling expedition into the East Coast Peninsula Malaysia Exclusive Economic Zone (EEZ) was carried in June 2008. Marine surface sediment samples were collected and the activity concentrations of 210 Pb have been determined. Its distribution was plotted and the findings show that the activity concentrations decline from north to south. On the other hand, the activity concentrations are increasing from west to east right to the edge of the EEZ. The 210 Pb activity concentrations were found to be in the range of 18.3 – 123.1 Bq/kg.

Surface soils of 2 cm depth were sampled at developed and undeveloped areas in Fraser's Hill, Pah... more Surface soils of 2 cm depth were sampled at developed and undeveloped areas in Fraser's Hill, Pahang, Malaysia. Thirty one (31) locations were collected and 226 Ra, 232 Th and 40 K activity concentrations were measured using HPGe Gamma Counting System. The mean radium equivalent activity concentration (Ra eq) for the sampled area was 463.37 Bq/kg. The Undeveloped area was found to have higher mean of Ra eq compared to Developed area. The mean Ra eq for each area was found to be 614.07 Bq/kg and 354.53 Bq/kg respectively. The external hazard index (H ex) were calculated and found to have a mean of 1.251. Undeveloped area was found to have higher mean of 1.658 compared to developed area with a mean of 0.957. Many locations were found to have H ex higher than 1.000.

Caesium-137 (137 Cs) in an anthropogenic radionuclide originated from the fission of fissile mate... more Caesium-137 (137 Cs) in an anthropogenic radionuclide originated from the fission of fissile materials. Nuclear weapons testing during the 1960s and the Chernobyl disaster introduced substantial amount of 137 Cs into the atmosphere that are then eventually deposited back to earth's surface. Caesium-137 can be used as tracer to study soil movements since it adsorbs to soil particles. This paper aims to describe the distribution of 137 Cs in surface soil of Fraser's Hill, Pahang, determine the levels of 137 Cs here compared to other areas, and to check correlation of 137 Cs levels to physical data. A series of sampling were carried out between February 2014 and August 2015. Soil samples were taken from 31 locations using soil scraper. The samples were then taken to the laboratory to be dried, homogenized, grinded and sieved. The activity concentration of 137 Cs in the samples was determined using gamma spectroscopy. The activity concentration was found to be between 0.26 Bq/kg and 5.14 Bq/kg. Although this paper only studies surface soil, 137 Cs is expected to be present within the soil body. Further study of 137 Cs in the soil body can be used to predictive model for soil erosion.

Journal of …, 2011

Large volumes of surface seawater samples were collected from thirty locations in the Exclusive E... more Large volumes of surface seawater samples were collected from thirty locations in the Exclusive Economic Zone (EEZ) of the east coast Peninsular Malaysia on June 2008 to study the activity concentrations of 137 Cs. The results will serve as additional information to the existing baseline data and is very useful for monitoring fresh input of anthropogenic radionuclide into Malaysian marine environment. In this study, the activity concentrations of 137 Cs were determined using co-precipitation technique, followed by Gamma Spectrometry measurement. The mean activity concentration of 137 Cs ranged between 3.40 and 5.89 Bq/m 3. Higher activity concentrations were observed at the coastal and towards the south of Peninsular Malaysia and were aligned with the high turbidity. These may due to the rapid diffusion of 137 Cs from suspended particulates and fine sediments into surface seawater. The activity concentrations of 137 Cs observed in this study were slightly higher than the concentrations reported in seawater at the Straits of Malacca, Vietnam and Philippines. This might be because the study area received more input of 137 Cs that originated from global fallout and then deposited on land which later being transported subsequently into the coastal zone due to siltation and erosion processes. It could also be attributed to the intrusion of river waters containing higher concentrations of 137 Cs.