[en] Adsorption is potentially an attractive technology for the treatment of waste water for retaining the heavy metals from dilute solutions. And it is one of the most common phenomenons for the treatment of lead-polluted water. The study evaluated here presents the experiments to determine the suitable conditions of Temperature, Contact Time, pH, Agitation Speed, Adsorbent Dose, Mesh Size and Metal Ion Concentration, for the use of Oryza Sativa (Rice) Straw, as adsorbent for the exclusion of lead from aqueous solution. The results revealed that maximum adsorption was observed at 20 degrees Celsius and at a contact time of 1.5 hr and an equilibrium time for keeping the ions adsorbed was observed between 0.5-1.5 hrs at a pH range of 6.9-7.0 and at an agitation speed of 150 rpm, with an adsorbent dose of 3.5 grams and mesh size 50-80, for as dilute metal ion concentrations as 16 ppm. (author)

[en] The catalytic oxidation of methanol to formaldehyde is studied over copper and silver catalysts. The impact of various factors catalytic poisoning, temperature, contact time on the formaldehyde yield have been investigated. An assembly using copper and silver as catalysts has been proposed to prepare formaldehyde in perspective of Pakistan in local industry. All the conditions to optimize the formaldehyde yield were also investigated. The formaldehyde produced was standardized chemically as well as spectroscopically. (author)

[en] Chemical oxygen demand (COD) is an important parameter in water-pollution control analysis. It is closely related to the organic contamination level of wastewater. The open-reflux Cr-COD titration method has long been the International standard method for COD determination /sup(1)/ however, it still requires a long time (2h) for the digestion step to be completed in this procedure. The objective of this research was to investigate the availability of a rapid procedure to determine the COD in wastewater by digesting samples in a microwave system followed by ferrous ammonium sulphate titration. The results obtained using this microwave aided digestion system were also compared with those obtained by conventional open reflux method. (author)

[en] Summary: Vegetables are generally boiled for cooking or stored in refrigerators. This results in loss of their nutritional values. Ascorbic acid is one of the important nutrients for human health. In this study, Ascorbic acid (vitamin-C) content of various vegetables of Pakistan was determined, and effect of boiling and freezing were compared with natural Ascorbic acid contents by HPLC. The maximum concentration of Ascorbic acid was found in green chilli: i.e. 105 mg /100 g in fresh state; while in boiled and frozen state its concentration is comparatively less: i.e. 85 and 92 mg/100 g respectively. The other vegetables like: cabbage, to mato, turnip, potato, spinach, onion, garlic, green pea, green beans and cauliflower contained greater amount of Ascorbic acid in their fresh state i.e. 30, 20, 25.3, 20, 30, 24.3, 31, 28.5, 30, 42 mg/100 g as compared to frozen (23.4, 13, 23.6, 15, 23.4, 14.1,25, 26.5, 27.0, and 39 mg/100g respectively) and boiled state (11.6, 9.3, 22.5, 10.0, 20.3, 13.1, 23, 25.2 and 35 mg /100g respectively). The minimum amount of Ascorbic acid was found in boiled state of carrot and lettuce: i.e. 4.0 mg/100 g. These results showed that freezing or boiling of vegetables causes significant lo ss of available Ascorbic acid contents, especially boiling. (author)

[en] Increasing fluoride levels in drinking water of fluorinated areas of world leading to fluorosis. For bio-monitoring of fluorosis patients, fluoride levels were determined in drinking water and human urine samples of different individuals having dental fluorosis and bony deformities from fluorotic area of Punjab (Sham Ki Bhatiyan, Pakistan) and then compared with reference samples of non fluorotic area (Queens Road, Lahore, Pakistan) using ion selective electrode methodology. Fluoride levels in fluorinated area differ significantly from control group (p < 0.05). In drinking water and human urine samples, fluoride levels in fluorinated areas were: 136.192 +- 67.836 and 94.484 +- 36.572 micro molL/sup -1/ respectively, whereas in control samples, fluoride concentrations were: 19.306 +- 2.109 and 47.154 +- 22.685 micro molL/sup -1/ in water and urine samples correspondingly. Pearson's correlation data pointed out the fact that that human urine and water fluoride concentrations have a significant positive dose response relationship with the prevalence of dental and skeletal fluorosis in fluorotic areas having higher fluoride levels in drinking water. (author)

[en] The wax emulsions have a great industrial importance as these are used in various fields like protective coatings of fruits, seeds, cemented material, paper boards etc. They showed great water repellency, lubrication, sewability and finishing tp the first product when applied to knitting yam in textile industry. In present work few useful emulsions are prepared by using paraffin and bees waxes. A variety of emulsifiers and stabilizers were checked to serve the purpose. The best sprayable emulsions were obtained using stearic acid triethanolamine and oleic acid triethanolamine as emulsifiers. Application on cemented materials was also checked. (author)

[en] Heavy metals have specific role in the progression of diseases. The aim of this study was to investigate the level of toxic elements, i.e. lead, cadmium, chromium and selenium in blood serum of type 1 diabetes mellitus and cancer patients. Samples were collected from Institute of Nuclear Medicine and Oncology, Lahore (INMOL) Hospital and Jinnah Hospital, Lahore. They were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES). Concentrations of toxic metals, i.e. lead, cadmium and chromium have been found relatively high in both cancer and diabetic patients where as concentration of selenium was relatively lower than the normal subjects. (author)

[en] An environmentally benign procedure for the bromination and chlorination of activated aromatic compounds has been developed by using ammonium halides as halogen source and KMnO/sub 4/ as oxidant generate positive halogen species. (author)

[en] The adsorption of Chromium(III) and Zinc(II) on ground pods of Pisum sativum (Garden peas) have been studied. The effects of adsorbent dose, pH, contact time and agitation speed on adsorption were studied. The study has revealed that pea pods have high metal removal efficiency. Cr(III) has been removed up to 80.92% and Zn(II) up to 75.11%. Adsorption equilibriums for both metals were developed, which were well described by the Langmuir and Freundlich isotherms. The maximum amounts of Cr(III) and Zn(II) adsorbed (Qmax), as evaluated by Langmuir isotherms were 1.88 mg and 1.45 mg per gram of pea pod's powder, respectively. It is anticipated that waste materials like pea pods can be used for removal of toxic metals like Cr(III) and Zn(II) from industrial effluents/waste waters. (author)

[en] Enaminones; 4-N,N-diethylamine-pent-3-ene-2-one [HL1], 4-N,N-di-n-propylamine-pent-3-ene-2-one [HL2] and 4-N,N-dicyclohexylamine-pent-3-ene-2-one [HL3] and their complexes with Ni (II) and Sb (III) ions were prepared by reacting the equimolar ethanolic solutions of the ligands (HL1, HL2 and HL3) with ethanolic metal ion solutions. The synthesized metal complexes were characterized by infrared, UV/Visible and atomic absorption spectroscopy. Metal complexes of Ni (II) and Sb (III) ions thus prepared, showed coordination numbers, four and six respectively. They were tested for their antibacterial activity against Escherichia coli and Staphylococcus aureus, staphylococcus epidermidis bacteria. Ligands were completely inactive against bacteria whereas the complexes of Sb (III) with ligands (HL/sub 1/, HL/sub 2/ and HL/sub 3/) have remarkable action on these bacteria, indicating that they have an ample potency as bactericide. Other complexes have normal bactericidal character. (author)