Abstract Although many metal elements are essential for the growth of plants in low concentration... more Abstract Although many metal elements are essential for the growth of plants in low concentrations, their excessive amounts in soil above threshold values can result in toxicity. This detrimental effect varies with the nature of an element as well as plant species. Heavy ...
Sealed radiation sources are commonly used in different research institutes, industries, and hosp... more Sealed radiation sources are commonly used in different research institutes, industries, and hospitals. The sources of various strengths are manufactured in different sizes and shapes. It is a regulatory requirement that these sources must be monitored frequently for their integrity and to avoid any radiological contamination hazard. Mainly, a wipe test is recommended for the contamination detection due to the leakage of sealed radiation sources. A radiation protection assistant robot has been fabricated to execute different tasks in a hazardous radiation environment. In this study, the robot was used to conduct the wipe test of five sealed radiation sources. The sealed radiation sources were tested safely and securely without giving any radiation dose to the radiation worker. The radiation doses received by the robot gripper and waist during the wipe test were 3.4 Gy and 208.9 mGy, respectively.
Abstract A new and convenient spectrophotometric method for the estimation of vanadium(IV) with N... more Abstract A new and convenient spectrophotometric method for the estimation of vanadium(IV) with NTA is described. The minimum ratio of metal ion to ligand, working pH, wavelength for maximum absorbance of the complex ion, and the effect of various cations and anions are described. The complex ion obeys Beer's law in the concentration range 1–32 mmol/liter of the vanadium(IV) ion. It is observed that iron(II), cobalt(II), nickel(II), copper(II), and oxidizing anions such as chromate and nitrite interfere in this determination, whereas managanese(II), chromium(III), iron(III), and anions like nitrate, chloride, bromide, iodide, thiocyanate, sulfate, and sulfite do not have any effect. Excessive amounts of acetate, phosphate, oxalate, tartrate and thiosulfate must also be avoided in this determination. Anions and cations which interfere in the determination of vanadium(IV) by NTA should not be present in the system.
The influence of various additives on the efficiency of optimized ozone bleaching process at pilo... more The influence of various additives on the efficiency of optimized ozone bleaching process at pilot scale has been discussed in this study. The results reveal that the best whiteness (63.79) and strength of bleached fabric is achieved with the addition of surfactant (2 g/L) at an ozone dose of 50 g/h, pH 5, and ozone treatment time of 45 min at room temperature. The dyeing quality of ozone-bleached and hydrogen peroxide-bleached fabric samples is almost identical. The analysis of variance of the experimental data validates that the process parameters have significantly affected the efficiency of ozone bleaching process.
The lack of potable water poses a big problem in southern and south-western arid regions of Pakis... more The lack of potable water poses a big problem in southern and south-western arid regions of Pakistan. The underground water, where exists, is usually brackish and cannot be used as it is for drinking purposes. Pakistan lies in high solar insolation band and the vast solar ...
Natural radionuclide contents of 226Ra, 228Ra and (40)K were studied for inter-tidal sediments co... more Natural radionuclide contents of 226Ra, 228Ra and (40)K were studied for inter-tidal sediments collected from selected locations off the745 km long Balochistan Coast using HPGe detector based gamma-spectrometry system. The sampling zone extends from the beaches of Sonmiani (near Karachi metropolis) through Jiwani (close to the border of Iran). The natural radioactivity levels detected in various sediment samples range from 14.4 +/- 2.5 to 36.6 +/- 3.8 Bq kg(-1) for 226Ra, 9.8 +/- 1.2 to 35.2 +/- 2.0 Bq kg(-1) for (228)Ra and 144.6 +/- 9.4 to 610.5 +/- 23.9 Bq kg(-1) for (40)K. No artificial radionuclide was detected in any of the marine coastal sediment samples. 137Cs, (60)Co, 106Ru and 144Ce contents in sediment samples were below the limit of detection. The measured radioactivity levels are compared with those reported in the literature for coastal sediments in other parts of the world. The information presented in this paper will serve as the first ever local radioactivity database for the Balochistan/Makran Coastal belt of Pakistan. The presented data will also contribute to the IAEA's, Asia-Pacific Marine Radioactivity Database (ASPAMARD) and the Global Marine Radioactivity Database (GLOMARD).
... References. MICROCHKMICAL JOIRXAL 22, 38 I 387 ( 1 977) Spectrophotometric Estimation of Coba... more ... References. MICROCHKMICAL JOIRXAL 22, 38 I 387 ( 1 977) Spectrophotometric Estimation of Cobalt(ll) with Nitrilotriacetic Acid NASIR AHMAD AND ... the presence of acetate ions improves the intensity of color (especially at the lower concentration region of metal ions) and ...
Magnetically responsive engineered smart thin films of nanoferrites as contrast agent are employe... more Magnetically responsive engineered smart thin films of nanoferrites as contrast agent are employed to develop surface based magnetic resonance imaging to acquire simple yet fast molecular imaging. The work presented here can be of significant potential for future lab-on-chip point-of-care diagnostics from the whole blood pool on almost any substrates to reduce or even prevent clinical studies involve a living organism to enhance the non-invasive imaging to advance the '3Rs' of work in animals-replacement, refinement and reduction.
Oil shales from two regions of Pakistan have been pyrolysed in a fixed bed reactor in relation to... more Oil shales from two regions of Pakistan have been pyrolysed in a fixed bed reactor in relation to particle grain size. Five size ranges were investigated,< 0.5, 0.51.0, 1.01.7, 1.72.8 and 6.010 mm. The pyrolysis system consisted of a 200 cm3 stainless steel fixed bed ...
Abstract Although many metal elements are essential for the growth of plants in low concentration... more Abstract Although many metal elements are essential for the growth of plants in low concentrations, their excessive amounts in soil above threshold values can result in toxicity. This detrimental effect varies with the nature of an element as well as plant species. Heavy ...
Sealed radiation sources are commonly used in different research institutes, industries, and hosp... more Sealed radiation sources are commonly used in different research institutes, industries, and hospitals. The sources of various strengths are manufactured in different sizes and shapes. It is a regulatory requirement that these sources must be monitored frequently for their integrity and to avoid any radiological contamination hazard. Mainly, a wipe test is recommended for the contamination detection due to the leakage of sealed radiation sources. A radiation protection assistant robot has been fabricated to execute different tasks in a hazardous radiation environment. In this study, the robot was used to conduct the wipe test of five sealed radiation sources. The sealed radiation sources were tested safely and securely without giving any radiation dose to the radiation worker. The radiation doses received by the robot gripper and waist during the wipe test were 3.4 Gy and 208.9 mGy, respectively.
Abstract A new and convenient spectrophotometric method for the estimation of vanadium(IV) with N... more Abstract A new and convenient spectrophotometric method for the estimation of vanadium(IV) with NTA is described. The minimum ratio of metal ion to ligand, working pH, wavelength for maximum absorbance of the complex ion, and the effect of various cations and anions are described. The complex ion obeys Beer's law in the concentration range 1–32 mmol/liter of the vanadium(IV) ion. It is observed that iron(II), cobalt(II), nickel(II), copper(II), and oxidizing anions such as chromate and nitrite interfere in this determination, whereas managanese(II), chromium(III), iron(III), and anions like nitrate, chloride, bromide, iodide, thiocyanate, sulfate, and sulfite do not have any effect. Excessive amounts of acetate, phosphate, oxalate, tartrate and thiosulfate must also be avoided in this determination. Anions and cations which interfere in the determination of vanadium(IV) by NTA should not be present in the system.
The influence of various additives on the efficiency of optimized ozone bleaching process at pilo... more The influence of various additives on the efficiency of optimized ozone bleaching process at pilot scale has been discussed in this study. The results reveal that the best whiteness (63.79) and strength of bleached fabric is achieved with the addition of surfactant (2 g/L) at an ozone dose of 50 g/h, pH 5, and ozone treatment time of 45 min at room temperature. The dyeing quality of ozone-bleached and hydrogen peroxide-bleached fabric samples is almost identical. The analysis of variance of the experimental data validates that the process parameters have significantly affected the efficiency of ozone bleaching process.
The lack of potable water poses a big problem in southern and south-western arid regions of Pakis... more The lack of potable water poses a big problem in southern and south-western arid regions of Pakistan. The underground water, where exists, is usually brackish and cannot be used as it is for drinking purposes. Pakistan lies in high solar insolation band and the vast solar ...
Natural radionuclide contents of 226Ra, 228Ra and (40)K were studied for inter-tidal sediments co... more Natural radionuclide contents of 226Ra, 228Ra and (40)K were studied for inter-tidal sediments collected from selected locations off the745 km long Balochistan Coast using HPGe detector based gamma-spectrometry system. The sampling zone extends from the beaches of Sonmiani (near Karachi metropolis) through Jiwani (close to the border of Iran). The natural radioactivity levels detected in various sediment samples range from 14.4 +/- 2.5 to 36.6 +/- 3.8 Bq kg(-1) for 226Ra, 9.8 +/- 1.2 to 35.2 +/- 2.0 Bq kg(-1) for (228)Ra and 144.6 +/- 9.4 to 610.5 +/- 23.9 Bq kg(-1) for (40)K. No artificial radionuclide was detected in any of the marine coastal sediment samples. 137Cs, (60)Co, 106Ru and 144Ce contents in sediment samples were below the limit of detection. The measured radioactivity levels are compared with those reported in the literature for coastal sediments in other parts of the world. The information presented in this paper will serve as the first ever local radioactivity database for the Balochistan/Makran Coastal belt of Pakistan. The presented data will also contribute to the IAEA's, Asia-Pacific Marine Radioactivity Database (ASPAMARD) and the Global Marine Radioactivity Database (GLOMARD).
... References. MICROCHKMICAL JOIRXAL 22, 38 I 387 ( 1 977) Spectrophotometric Estimation of Coba... more ... References. MICROCHKMICAL JOIRXAL 22, 38 I 387 ( 1 977) Spectrophotometric Estimation of Cobalt(ll) with Nitrilotriacetic Acid NASIR AHMAD AND ... the presence of acetate ions improves the intensity of color (especially at the lower concentration region of metal ions) and ...
Magnetically responsive engineered smart thin films of nanoferrites as contrast agent are employe... more Magnetically responsive engineered smart thin films of nanoferrites as contrast agent are employed to develop surface based magnetic resonance imaging to acquire simple yet fast molecular imaging. The work presented here can be of significant potential for future lab-on-chip point-of-care diagnostics from the whole blood pool on almost any substrates to reduce or even prevent clinical studies involve a living organism to enhance the non-invasive imaging to advance the '3Rs' of work in animals-replacement, refinement and reduction.
Oil shales from two regions of Pakistan have been pyrolysed in a fixed bed reactor in relation to... more Oil shales from two regions of Pakistan have been pyrolysed in a fixed bed reactor in relation to particle grain size. Five size ranges were investigated,< 0.5, 0.51.0, 1.01.7, 1.72.8 and 6.010 mm. The pyrolysis system consisted of a 200 cm3 stainless steel fixed bed ...
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