Mohammed Salim | University College Dublin (original) (raw)

Papers by Mohammed Salim

Journal of Cleaner Production

Despite studies have demonstrated the possibilities of using water in diesel emulsion fuel to red... more Despite studies have demonstrated the possibilities of using water in diesel emulsion fuel to reduce the harmful exhaust emission, limited studies are available at present on the effect of emulsified diesel towards metal corrosion. This study therefore aims to investigate the corrosion behaviour of copper exposed to emulsified diesel. Copper immersion tests in diesel, biodiesel and emulsified diesel were carried out for 1200 h at 25 C. Similar immersion test in emulsified diesel was also carried out for 240 h, 480 h, 720 h, 960 h and 1200 h at 25 C. Two emulsifiers such as Span 80 and Tween 80 were used to prepare emulsion consisting of 5 vol% of water in diesel. Among the performed analysis were mass loss, surface morphology, elemental composition, surface topography, surface roughness, microscopy, Fourier transform infrared spectroscopy, emulsion characterization, density, viscosity, water content and total acid number. 11.7 times and 4.7 times higher corrosion rate occurred to the copper coupon exposed to emulsified diesel as compared to diesel and biodiesel, respectively. 68% reduction in corrosion rate occurred for the copper exposed to emulsified diesel between 240 h and 1200 h of immersion duration. Up to 3.6 mm and 1.7 mm in pit depth and width, respectively, formed on the copper surface exposed to emulsified diesel for 1200 h at 25 C. The increased acidity of emulsified diesel by 4.5 times as compared to diesel due to the addition of emulsifiers to form stable water in diesel emulsion is suggested to have caused the increased corrosion rate. Neutralization and/or use of less acidic emulsifier are recommended to reduce the corrosive effect of emulsified diesel. More works on this area are required to establish the compatibility present between emulsified diesel and fuel delivery metals.

Journal of Instrumentation, 2015

The India based Neutrino Observatory (INO) collaboration is planning to build a 50 kton magnetize... more The India based Neutrino Observatory (INO) collaboration is planning to build a 50 kton magnetized Iron Calorimeter (ICAL) detector to study neutrino oscillations and measure their associated parameters. ICAL will use 28,800 glass Resistive Plate Chambers (RPCs) of 2 m×2 m in size as its active detector elements. These RPCs will be operated in the avalanche mode. As a part of the detector R&D to develop the RPCs required for this detector, we made a comparative study of the effect of Sulphur Hexafluoride (SF 6) in the gas mixture on the induced charge using simulation and experimental data in our earlier paper [1]. In this paper, we extend our studies to efficiency and time resolution of the RPC using simulation and experimental data. Several software tools have been used to carry out the simulation. We have calculated the primary interaction parameters using HEED and Geant4. The electron transport parameters have been computed using MAGBOLTZ. We have used nearly exact Boundary Element Method (neBEM) and COMSOL Multiphysics, a Finite Element Method package for calculating the weighting field and the electric field. KEYWORDS: Gaseous detectors; Resistive-plate chambers; Detector modelling and simulations II (electric fields, charge transport, multiplication and induction, pulse formation, electron emission, etc); Detector modelling and simulations I (interaction of radiation with matter, interaction of photons with matter, interaction of hadrons with matter, etc)

Journal of the Indian Society of Remote Sensing, 2014

ABSTRACT Scattering and absorption of solar radiation by anthropogenic aerosols reduce the photos... more ABSTRACT Scattering and absorption of solar radiation by anthropogenic aerosols reduce the photosynthetic active radiation (PAR) incident on the Earth surface and the changes incident PAR can cause contradictory responses in terrestrial plants. The reduction of incident PAR is mainly varied according to the regional characteristics and forcing efficiency of aerosols. The MODIS derived atmospheric products are widely used for many such environmental investigations. In this paper a radiative transfer model is developed in cloudless clear sky condition to estimate instantaneous PAR and radiative forcing of aerosol. The estimated instantaneous PAR is validated with the ground measured (AccuPAR model LP-80) incident PAR during 2009. The Mean Absolute Error (MAE) of MODIS based incident PAR simulations was 20.09 w/m2 and Absolute Percentage Difference (APD) was 6.9 % while the MAE of Microtops II based estimations of incident PAR was 7.5 w/m2 and APD was 2.4 % . Inter comparison of estimations incident PAR with sun-photometer and MODIS measurements showed that the MODIS based PAR is over estimated mainly due to the under estimation ofMODIS AOD over the study area. The model can generate spatial maps of instantaneous PAR and aerosol forcing efficiency. An Improved PAR map was generated (MAE 7.6 w/m2 and APD 2.5 %) by correcting MODIS AOD based on Microtops II measurements.

ABSTRACT A terrain-following ocean model is implemented for simulating three-dimensional tidal an... more ABSTRACT A terrain-following ocean model is implemented for simulating three-dimensional tidal and residual circulations in the Gulf of Khambhat and its adjacent oceans on the west coast of India. The model is forced with time varying tidal levels and momentum fluxes at the western and southern boundaries. Simulated tidal levels and currents compare well with the observation at tide gauge and current-meter stations. Estimated residual circulation in the region has several notable features that include strong southward along channel flow inside the gulf, northwestward propagating coastal boundary jet currents parallel the 60 m isobaths, southward slope currents, alongshore coastal currents on the southeastern flank of the shelf and a number of meso-scale eddies. All these features of residual circulation are captured well by the satellite imagery of Chlorophyll concentration mapped in the month of March, the period when tide plays dominant role on the control of net circulation in the region.

Cancer, 2003

BACKGROUND. The goals of the current study were to examine the incidence and severity of toxicity... more BACKGROUND. The goals of the current study were to examine the incidence and severity of toxicity resulting from dexamethasone and prednisone during induction therapy for children with precursor B-cell acute lymphoblastic leukemia (ALL) and to determine whether the addition of daunomycin affected toxicity. METHODS. Medical records of patients with precursor B-cell ALL from January 1996 through June 2000 were reviewed retrospectively for toxicity during the 4-week induction phase and the 2 weeks after the induction phase. RESULTS. One hundred seventy-six patients age Ͻ 14 years were diagnosed with precursor B-cell ALL from January 1996 through June 2000. Of the 156 evaluable patients, 106 were treated with prednisone and 50 with dexamethasone. Fifty-two patients received steroids, L-asparaginase, and vincristine, whereas 104 high-risk patients received daunomycin in addition to these 3 agents. The incidence of gastritis was significantly higher among patients receiving dexamethasone (P ϭ 0.01); incidence rates of hyperglycemia, hypertension, and myopathy were similar for all treatment groups. Dexamethasone led to more weight gain than did prednisone (ϩ11.9% vs. ϩ5.4%; P ϭ 0.002). Serious infections were observed in 27 (25.5%) and 18 (36%) patients receiving prednisone and dexamethasone, respectively (P Յ 0.2). Five patients, four of whom received prednisone and one of whom received dexamethasone, died of infection. The addition of daunomycin to treatment regimens increased overall toxicity (P Ͻ 0.01). When daunomycin was included in treatment regimens, toxicity was greater among patients receiving dexamethasone; in contrast, when daunomycin was not included, toxicity was equal for both treatment groups. Regardless of daunomycin use, there was no difference in the incidence of serious infection between the two groups. ALL treatment was not compromised by steroid-related toxicity in either group. CONCLUSIONS. The addition of daunomycin led to a much larger increase in dexamethasone-related toxicity compared with the increase in prednisone-related toxicity. Although the use of daunomycin enhanced dexamethasone-related toxicity, this enhancement did not result in a higher mortality rate or the alteration of planned ALL therapy.

Bioorganic & Medicinal Chemistry Letters, 2009

Antiviral Research, 2010

Several novel γ-carboline derivatives were identified as selective inhibitors of bovine viral dia... more Several novel γ-carboline derivatives were identified as selective inhibitors of bovine viral diarrhea virus (BVDV) replication in cell cultures. Among them, 3,4,5-trimethyl-γ-carboline (SK3M4M5M) was the most active against BVDV (Nose strain) in MDBK cells, with a 50% effective concentration of 0.017±0.005μM and a selectivity index of 435. The compound inhibited viral RNA synthesis in a dose-dependent fashion. In a time of drug-addition experiment during a single viral replication cycle, SK3M4M5M lost its antiviral activity when first added at 8h or later after infection, which coincides with the onset of viral RNA synthesis. When selected γ-carboline derivatives, including SK3M4M5M, were examined for their inhibitory effect on the mutant strains resistant to some classes of nonnucleoside BVDV RNA-dependent RNA polymerase inhibitors, all of which target the top of the finger domain of the polymerase, the strains displayed cross-resistance to the γ-carboline derivatives. These results indicate that the γ-carboline derivatives may possibly target a hot spot of the RNA-dependent RNA polymerase. Although SK3M4M5M was highly active against BVDV, the compound proved inactive against hepatitis C virus (HCV) in HCV RNA replicon cells.

Journal of Cleaner Production

Despite studies have demonstrated the possibilities of using water in diesel emulsion fuel to red... more Despite studies have demonstrated the possibilities of using water in diesel emulsion fuel to reduce the harmful exhaust emission, limited studies are available at present on the effect of emulsified diesel towards metal corrosion. This study therefore aims to investigate the corrosion behaviour of copper exposed to emulsified diesel. Copper immersion tests in diesel, biodiesel and emulsified diesel were carried out for 1200 h at 25 C. Similar immersion test in emulsified diesel was also carried out for 240 h, 480 h, 720 h, 960 h and 1200 h at 25 C. Two emulsifiers such as Span 80 and Tween 80 were used to prepare emulsion consisting of 5 vol% of water in diesel. Among the performed analysis were mass loss, surface morphology, elemental composition, surface topography, surface roughness, microscopy, Fourier transform infrared spectroscopy, emulsion characterization, density, viscosity, water content and total acid number. 11.7 times and 4.7 times higher corrosion rate occurred to the copper coupon exposed to emulsified diesel as compared to diesel and biodiesel, respectively. 68% reduction in corrosion rate occurred for the copper exposed to emulsified diesel between 240 h and 1200 h of immersion duration. Up to 3.6 mm and 1.7 mm in pit depth and width, respectively, formed on the copper surface exposed to emulsified diesel for 1200 h at 25 C. The increased acidity of emulsified diesel by 4.5 times as compared to diesel due to the addition of emulsifiers to form stable water in diesel emulsion is suggested to have caused the increased corrosion rate. Neutralization and/or use of less acidic emulsifier are recommended to reduce the corrosive effect of emulsified diesel. More works on this area are required to establish the compatibility present between emulsified diesel and fuel delivery metals.

Journal of Instrumentation, 2015

The India based Neutrino Observatory (INO) collaboration is planning to build a 50 kton magnetize... more The India based Neutrino Observatory (INO) collaboration is planning to build a 50 kton magnetized Iron Calorimeter (ICAL) detector to study neutrino oscillations and measure their associated parameters. ICAL will use 28,800 glass Resistive Plate Chambers (RPCs) of 2 m×2 m in size as its active detector elements. These RPCs will be operated in the avalanche mode. As a part of the detector R&D to develop the RPCs required for this detector, we made a comparative study of the effect of Sulphur Hexafluoride (SF 6) in the gas mixture on the induced charge using simulation and experimental data in our earlier paper [1]. In this paper, we extend our studies to efficiency and time resolution of the RPC using simulation and experimental data. Several software tools have been used to carry out the simulation. We have calculated the primary interaction parameters using HEED and Geant4. The electron transport parameters have been computed using MAGBOLTZ. We have used nearly exact Boundary Element Method (neBEM) and COMSOL Multiphysics, a Finite Element Method package for calculating the weighting field and the electric field. KEYWORDS: Gaseous detectors; Resistive-plate chambers; Detector modelling and simulations II (electric fields, charge transport, multiplication and induction, pulse formation, electron emission, etc); Detector modelling and simulations I (interaction of radiation with matter, interaction of photons with matter, interaction of hadrons with matter, etc)

Journal of the Indian Society of Remote Sensing, 2014

ABSTRACT Scattering and absorption of solar radiation by anthropogenic aerosols reduce the photos... more ABSTRACT Scattering and absorption of solar radiation by anthropogenic aerosols reduce the photosynthetic active radiation (PAR) incident on the Earth surface and the changes incident PAR can cause contradictory responses in terrestrial plants. The reduction of incident PAR is mainly varied according to the regional characteristics and forcing efficiency of aerosols. The MODIS derived atmospheric products are widely used for many such environmental investigations. In this paper a radiative transfer model is developed in cloudless clear sky condition to estimate instantaneous PAR and radiative forcing of aerosol. The estimated instantaneous PAR is validated with the ground measured (AccuPAR model LP-80) incident PAR during 2009. The Mean Absolute Error (MAE) of MODIS based incident PAR simulations was 20.09 w/m2 and Absolute Percentage Difference (APD) was 6.9 % while the MAE of Microtops II based estimations of incident PAR was 7.5 w/m2 and APD was 2.4 % . Inter comparison of estimations incident PAR with sun-photometer and MODIS measurements showed that the MODIS based PAR is over estimated mainly due to the under estimation ofMODIS AOD over the study area. The model can generate spatial maps of instantaneous PAR and aerosol forcing efficiency. An Improved PAR map was generated (MAE 7.6 w/m2 and APD 2.5 %) by correcting MODIS AOD based on Microtops II measurements.

ABSTRACT A terrain-following ocean model is implemented for simulating three-dimensional tidal an... more ABSTRACT A terrain-following ocean model is implemented for simulating three-dimensional tidal and residual circulations in the Gulf of Khambhat and its adjacent oceans on the west coast of India. The model is forced with time varying tidal levels and momentum fluxes at the western and southern boundaries. Simulated tidal levels and currents compare well with the observation at tide gauge and current-meter stations. Estimated residual circulation in the region has several notable features that include strong southward along channel flow inside the gulf, northwestward propagating coastal boundary jet currents parallel the 60 m isobaths, southward slope currents, alongshore coastal currents on the southeastern flank of the shelf and a number of meso-scale eddies. All these features of residual circulation are captured well by the satellite imagery of Chlorophyll concentration mapped in the month of March, the period when tide plays dominant role on the control of net circulation in the region.

Cancer, 2003

BACKGROUND. The goals of the current study were to examine the incidence and severity of toxicity... more BACKGROUND. The goals of the current study were to examine the incidence and severity of toxicity resulting from dexamethasone and prednisone during induction therapy for children with precursor B-cell acute lymphoblastic leukemia (ALL) and to determine whether the addition of daunomycin affected toxicity. METHODS. Medical records of patients with precursor B-cell ALL from January 1996 through June 2000 were reviewed retrospectively for toxicity during the 4-week induction phase and the 2 weeks after the induction phase. RESULTS. One hundred seventy-six patients age Ͻ 14 years were diagnosed with precursor B-cell ALL from January 1996 through June 2000. Of the 156 evaluable patients, 106 were treated with prednisone and 50 with dexamethasone. Fifty-two patients received steroids, L-asparaginase, and vincristine, whereas 104 high-risk patients received daunomycin in addition to these 3 agents. The incidence of gastritis was significantly higher among patients receiving dexamethasone (P ϭ 0.01); incidence rates of hyperglycemia, hypertension, and myopathy were similar for all treatment groups. Dexamethasone led to more weight gain than did prednisone (ϩ11.9% vs. ϩ5.4%; P ϭ 0.002). Serious infections were observed in 27 (25.5%) and 18 (36%) patients receiving prednisone and dexamethasone, respectively (P Յ 0.2). Five patients, four of whom received prednisone and one of whom received dexamethasone, died of infection. The addition of daunomycin to treatment regimens increased overall toxicity (P Ͻ 0.01). When daunomycin was included in treatment regimens, toxicity was greater among patients receiving dexamethasone; in contrast, when daunomycin was not included, toxicity was equal for both treatment groups. Regardless of daunomycin use, there was no difference in the incidence of serious infection between the two groups. ALL treatment was not compromised by steroid-related toxicity in either group. CONCLUSIONS. The addition of daunomycin led to a much larger increase in dexamethasone-related toxicity compared with the increase in prednisone-related toxicity. Although the use of daunomycin enhanced dexamethasone-related toxicity, this enhancement did not result in a higher mortality rate or the alteration of planned ALL therapy.

Bioorganic & Medicinal Chemistry Letters, 2009

Antiviral Research, 2010

Several novel γ-carboline derivatives were identified as selective inhibitors of bovine viral dia... more Several novel γ-carboline derivatives were identified as selective inhibitors of bovine viral diarrhea virus (BVDV) replication in cell cultures. Among them, 3,4,5-trimethyl-γ-carboline (SK3M4M5M) was the most active against BVDV (Nose strain) in MDBK cells, with a 50% effective concentration of 0.017±0.005μM and a selectivity index of 435. The compound inhibited viral RNA synthesis in a dose-dependent fashion. In a time of drug-addition experiment during a single viral replication cycle, SK3M4M5M lost its antiviral activity when first added at 8h or later after infection, which coincides with the onset of viral RNA synthesis. When selected γ-carboline derivatives, including SK3M4M5M, were examined for their inhibitory effect on the mutant strains resistant to some classes of nonnucleoside BVDV RNA-dependent RNA polymerase inhibitors, all of which target the top of the finger domain of the polymerase, the strains displayed cross-resistance to the γ-carboline derivatives. These results indicate that the γ-carboline derivatives may possibly target a hot spot of the RNA-dependent RNA polymerase. Although SK3M4M5M was highly active against BVDV, the compound proved inactive against hepatitis C virus (HCV) in HCV RNA replicon cells.