Synthesis and characterization of drinking water treatment plant sludge-incorporated Portland cement

Kinetic analysis of thermally activated phase transformations in drinking water treatment plant (DWTP) sludge suggests its applicability in the materials of construction. The suggested prediction has already been verified on the sludge-based bricks. The present study deals with incorporating the same sludge in the raw meal for the synthesis of Portland cement clinkers. For this purpose, two raw meals are prepared with varying sludge loadings. The sludge effect on reactivity of the crude mixture is evaluated on the basis of the free lime content sintered at various elevated temperatures. The results of chemical and mineralogical and scanning electron microscopic analyses reveal fine mineralogical contents of Portland clinkers calcined at 1450 and 1500 °C. Moreover, the cements prepared from these clinkers by the introduction of certain proportions of gypsum, depict significant durability. The obtained results elucidate that the studied DWTP sludge-incorporated Portland cement shows considerable potential to be commercialized.     

Aluminum interaction with human brain tau protein phosphorylation by various Kinases

Abstract

Phosphorylation is an indispensable process for energy and signal transduction in biological systems. AlCl₃ at 10 nM to 10 uM range activated in‐vitro [γ‐³²P)ATP phosphorylation of the brain (tau) T protein in both normal human or E.coli expressed T forms; in the presence of the kinases P34, PKP, and PKC. However, higher concentrations of ALCl₃ inhibited the T phosphorylation with P34, PKP, and PKC to a maximum at 1 mM level. AlCl₃ at 100 uM to 500 uM range induced non‐enzymatic phosphorylation of T with γ‐ATP, γ‐GTP, and α‐GTP. AlCl₃ activated histone phosphorylation by P34 in a similar pattern. The hyperphosphorylation of T by Al³⁺ was accompanied by molecular shift and mobility retardation in SDS‐PAGE. This may demonstrate the mechanism of the longterm neurological effect of Al³⁺ in human brain leading to the formation of the neurofibrillary tangles related to Alzeheimer's disease.     

Effects of sublethal concentrations of permethrin on bioaccumulation of cadmium in zebra cichlid (Cichlasoma nigrofasciatum)

The aim of this study was to evaluate the synergistic and antagonistic effects of permethrin on the bioaccumulation of cadmium in zebra cichlid (Cichlasoma nigrofasciatum). Zebra cichlid was exposed to various sublethal concentrations of permethrin combined with cadmium chloride for 15 days. Although at the lowest concentrations, permethrin (0.40 µg L^?1) decreased the bioconcentration potential of cadmium in fish, bioaccumulation of cadmium increased along with increasing concentrations of permethrin (0.80–1.20 µg L^?1). However, the magnitude of changes in the accumulation of cadmium in the fishes simultaneously exposed to 1.60 µg L^?1 permetrin and cadmium chloride was similar to the cadmium levels observed in fishes after exposure to the cadmium chloride alone. The results of this study suggest that the synergistic effects of permethrin on the bioaccumulation of cadmium highly depend on the concentrations of this pesticide in water.     

Ultrasound-assistant preparation of Cu-SAPO-34 nanocatalyst for selective catalytic reduction of NO by NH3

The influence of the various preparation methods of Cu-SAPO-34 nanocatalysts on the selective catalytic reduction of NO with NH₃ under excess oxygen was studied. Cu-SAPO-34 nanocatalysts were prepared by using four techniques: conventional impregnation (IM), ultrasound-enhanced impregnation (UIM), conventional deposition precipitation (DP) using NaOH and homogeneous deposition precipitation (HDP) using urea. These catalysts were characterized in detail by various techniques such as N₂-sorption, XRD, TEM, H₂-TPR, NH₃-TPD and XPS to understand the catalyst structure, the nature and the dispersed state of the copper species, and the acid sites for NH₃ adsorption. All of the nanocatalysts showed high activities for NO removal. However, the activities were different and followed the sequence of Cu-SAPO-34 (UIM) > Cu-SAPO-34 (HDP) > Cu-SAPO-34 (IM) > Cu-SAPO-34 (DP). Based on the obtained results, it was concluded that the NO conversion on Cu-SAPO-34 nanocatalysts was mainly related to the high reducibility of the isolated Cu^2 + ions and CuO species, the number of the acid sites and the dispersion of CuO species on SAPO-34.     

Sequential UV-biological degradation of chlorophenols

The sequential UV-biological degradation of a mixture of 4-chlorophenol (CP), 2,4-dichlorophenol (DCP), 2,4,6-trichlorophenol (TCP), and pentachlorophenol (PCP) was first tested with each pollutant supplied at an initial concentration of 50 mg l(-1). Under these conditions, the chlorophenols were photodegraded in the following order of removal rate: PCP>TCP>DCP>CP with only CP and DCP remaining after 40 h of irradiation. The remaining CP (41 mg l(-1)) and DCP (13 mg l(-1)) were then completely removed by biological treatment with an activated sludge mixed culture. Biodegradation did not occur in similar tests conducted with a non-irradiated mixture due to the high microbial toxicity of the solution. UV treatment lead to a significant reduction of the phytotoxicity to Lipedium sativum but no further reduction of phytotoxicity was observed after biological treatment. Evidence was found that the pollutants were partially photodegraded into toxic and non-biodegradable products. When the pollutants were tested individually (initial concentration of 50 mg l(-1)), PCP, TCP, DCP, 4-CP were photodegraded according to first order kinetic model (r2>99) with half-lives of 2.2, 3.3, 5.7, and 54 h, respectively. The photoproducts were subsequently biodegraded. This study illustrates the potential of UV as pre-treatment for biological treatment in order to remove toxicity and enhance the biodegradability of organic contaminants. However, it also shows that UV treatment must be carefully optimized to avoid the formation of toxic and/or recalcitrant photoproducts and results from studies conducted on single contaminants cannot be extrapolated to mixtures.     

HYDROLOGICAL,METEOROLOGICAL, AND AGRICULTURAL RELATIONS IN NORTHERN IRAQ1

ABSTRACT: The northern regions of Iraq, an area comprised of mountains and undulating plains, has for centuries been the main granary for the country. Its agricultural production is largely dependent upon natural rainfall which ranges from about 300 to 1,000 mm/yr. Grain yields can be greatly improved by use of improved varieties and management practices. Equations are developed to show relationships between various hydrologic and meteorologic parameters with yields of wheat and barley. The amount of supplementary water needed to maximize grain yields is also shown.     

Long-Term Maintenance of Rapid Atrazine Degradation in Soils Inoculated with Atrazine Degraders

Two different microbial communities able to degrade atrazine (atz) were inoculated in four different soils. The most critical factor affecting the success of inoculation was the soil pH and its organic matter (OM) content. In two alkaline soils (pH > 7), some inoculations led immediately to a strong increase of the biodegradation rate. In a third slightly acidic soil (pH = 6.1), only one inoculum could enhance atz degradation. In a soil amended with organic matter and straw (pH = 5.7, OM = 16.5%), inoculation had only little effect on atz dissipation on the short as well as on the long-term. Nine months after the microflora inoculations, atz was added again and rapid biodegradation in all alkaline inoculated soils was recorded, indicating the long-term efficiency of inoculation. In these soils, the number of atz degraders was estimated at between 6.5 × 10³ and 1.5 × 10⁶ (g of soil)^-1, using the most probable number (MPN) method. Furthermore, the presence of the atz degraders was confirmed by the detection of the gene atzA in these soils. Denaturing gradient gel electrophoresis (DGGE) analysis of the 16S rDNA genes indicated that the inoculated bacterial communities had little effect on the patterns of the indigenous soil microflora.     

Freight transport and non-driving work duties as predictors of falling asleep at the wheel in urban areas of Crete

BACKGROUND: This study investigated the impact of subjective reports of drowsy driving and non-driving duties on the falling asleep responses and road crash involvement of professional drivers in Crete. An attempt was also made to elucidate other driving parameters, such as freight transportation, which could be potential predictors of risky driving, after controlling for lifestyle patterns. METHOD: A sample of 317 professional drivers was studied through personal interviews. The interview questionnaire included items about sleep and fatigue as contributing factors to falling asleep probability and crash risk. In addition, the drivers reported the type of freight they carried in their last trip, as well as practices such as smoking and alcohol consumption. RESULTS: The first logistic regression analysis showed that the most significant predictors of falling asleep at the wheel were transportation of fruits/vegetables and livestock, non-driving hours of work, insufficient hours of sleep, and smoking. The second logistic regression analysis revealed all the previous items as powerful factors of crash probability, including the transportation of express freight and freezer. IMPACT: The findings of the current study are discussed as they pertain to directions for future studies and for the development of fatigue countermeasures.