The effect of zeolite treatment by acids on sodium adsorption ratio of coal seam gas water

Many coal seam gas (CSG) waters contain a sodium ion concentration which is too high relative to calcium and magnesium ions for environment acceptance. Natural zeolites can be used as a cheap and effective method to control sodium adsorption ratio (SAR, which is a measure of the relative preponderance of sodium to calcium and magnesium) due to its high cation exchange capacity. In this study, a natural zeolite from Queensland was examined for its potential to treat CSG water to remove sodium ions to lower SAR and reduce the pH value. The results demonstrate that acid activated zeolite at 30%wt solid ratio can reduce the sodium content from 563.0 to 182.7 ppm; the pH from 8.74 to 6.95; and SAR from 70.3 to 18.5. Based on the results of the batch experiments, the sodium adsorption capacity of the acid-treated zeolite is three times greater than that of the untreated zeolite. Both the untreated and acid-treated zeolite samples were characterized using zeta potential, surface characterization, DTA/TG and particle size distribution in order to explain their adsorption behaviours.     

Determination of the antigenotoxic potencies of some luteolin derivatives by using a eukaryotic cell system, Saccharomyces cerevisiae

In this study, we aimed to examine the mutagenic and antimutagenic potencies of three luteolin derivatives (luteolin-7-O-glucoside, luteolin-7-O-rutinoside and luteolin-7-O-glucuronide) by using a eukaryotic cell system, Saccharomyces cerevisiae (RS112).     

Cobalt(II), Zinc(II) and Cadmium(II)-Squarate Complexes with N-Methylimidazole

Three M(II)-squarate complexes, [Co(sq)(H₂O)(Nmim)₄] (1), [Zn(μ_1,3-sq)(H₂O)₂ (Nmim)₂] _n (2) and [Cd(μ_1,3-sq)(H₂O)₂(Nmim)₂] _n (3) (sq = squarate, Nmim = N-methylimidazole) have been synthesized and characterized by elemental, spectral (IR and UV–Vis.) and thermal analyses. The molecular structures of the complexes have been investigated by single crystal X-ray diffraction technique. The squarate ligand acts as two different coordination modes as a monodentate (in 1) and bis(monodentate) (O ^1– O ³ ) bridging ligand (in 2, 3). The Co(II) atom has a distorted octahedral geometry with the basal plane comprised of three nitrogen atoms of Nmim ligands and a oxygen atom of squarate ligand. The axial position is occupied by a nitrogen atom of Nmim and one aqua ligand. The crystallographic analysis reveals that the crystal structures of 2 and 3 are one-dimensional linear chain polymers along the c and b axis, respectively. The configuration around each metal(II) ions are distorted octahedral geometry with two nitrogen atoms of trans-Nmim, two aqua ligands and two oxygen atoms of squarate-O¹,O³ ligand. These chains are held together by the C–H···π, π···π and hydrogen-bonding interactions, forming three-dimensional network.     

The dependence of tool overhang on surface quality and tool wear in the turning process

In the turning process, the importance of machining parameter choice is increased, as it controls the surface quality required. Tool overhang is a cutting tool parameter that has not been investigated in as much detail as some of the better known ones. It is appropriate to keep the tool overhang as short as possible; however, a longer tool overhang may be required depending on the geometry of the workpiece and when using the hole-turning process in particular. In this study, we investigate the effects of changes in the tool overhang in the external turning process on both the surface quality of the workpiece and tool wear. For this purpose, we used workpieces of AISI 1050 material with diameters of 20, 30, and 40 mm; and the surface roughness of the workpiece and tool wear were determined through experiments using constant cutting speed and feed rates with different depth of cuts (DOCs) and tool overhangs. We observed that the effect of the DOC on the surface roughness is negligible, but tool overhang is more important. The deflection of the cutting tool increases with tool overhang. Two different analytical methods were compared to determine the dependence of tool deflection on the tool overhang. Also, the real tool deflection values were determined using a comparator. We observed that the tool deflection values were quite compatible with the tool deflection results obtained using the second analytical method.     

An analysis of cracked beam structure using impact echo method

Defects influence in a negative way the service life of structures. Thus, detection of them even at a very small size is a very important point of view to guarantee structural safety and to safe costs. The objective of this study is to obtain information about the location and depth of cracks in cracked beams. For this purpose, the vibrations as a result of impact shocks were analyzed. The signals obtained in defect-free and cracked beams were compared in the frequency domain. The results of the study suggest to determine the location and depth of cracks by analyzing the from vibration signals. Experimental results and simulations obtained by the software ANSYS are in good agreement.     

Effect of the particle size of finishing chemicals on the color assessment of treated cotton fabrics

Color change is one of the important side effects of textile treatments to consider. This article evaluates the effect of the particle size of commonly used finishing chemicals (fluorocarbon resins and dimethyloldihydroxylethylene urea reagents) on color assessment by studying instrumental analyses, and it is reported that the smaller the particle size is, the higher the surface reflectance is, and the less the color change can be achieved. On the other hand, the effect of the particle size is not significant on color assessment after abrading cycles. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

Hydro-abrasive erosion of concrete incorporating ground blast-furnace slag and ground basaltic pumice

In this research work, an attempt has been made to find the suitability of the ground blast-furnace slag (GBS) and ground basaltic pumice (GBP) as a possible substitute for conventional crushed fine aggregate. The main purpose of this investigation is to determine the hydro-abrasive erosion (HAE) characteristics of concrete with GBS and GBP as fine aggregates.The results create perspectives of forecasting HAE of concrete structures depending on the types and amount of additives. It was found that the HAE characteristics of concrete had improved when some of the fine aggregates were replaced by GBS and GBP. As the amount of these additives increased, the mass loss of the concrete incorporating GBS + GBP decreased. This improvement can be explained partly by the decrease in the permeability and partly by the HAE resistance of the additives. In addition to these results, the HAE of concrete was strongly influenced by its compressive strength. Furthermore, the increase in the percentage of additives increased the chloride penetration depths, sharply. The results of this investigation suggest that a joint incorporation of GBS and GBP could conveniently be used to improve its HAE characteristics of concrete.     

A highly novel dinickel complex: A hydrogen-bonded anti-skew carboxylate bridge and a 2D supramolecular structure

Reaction of the tridentate Schiff base ligands obtained from 2,4-dihydroxybenzaldehyde and either l-isoleucine or l-tert-leucine with Ni(NO₃)₂ in methanol/water solution in the presence of base afforded dinickel complexes. The crystal structure of the product derived from l-tert-leucine has been determined by X-ray crystallography. The octahedrally coordinated two Ni centers were found to be bridged by a single carboxylate group in an extremely unusual non-planar fashion. A 2D supramolecular structure, constructed by infinite hydrogen-bonded complex sheets parallel to the ab-plane of the unit cell, arises from intermolecular O–H?O hydrogen bonds.     

Investigation of neutronic performance of a peaceful nuclear explosive reactor (PACER) evaluating UF<Subscript>4</Subscript> and ThF<Subscript>4</Subscript> nuclides

In this study, neutronic behaviour of a peaceful nuclear explosion reactor (PACER) producing approx 1·2 GWe power from fusion explosions is analysed considering ThF₄ and UF₄ as fissile zones. UF₄ and ThF₄ are put in to the system adjacent to the inner-side of the flibe coolant zone positions (distance between explosive region and fuel zone,DR = 50, 100, 200, 400, 500 and 700 cm). Flibe percentages are taken to be 25, 50, 75 and 100%. It is found that optimum combinations of fissile zone thickness, coolant zone position and coolant percentages are 10 cm, 200 cm and 25% flibe for UF₄ and 10 cm, 50 cm and 25% flibe for ThF₄. The behaviour of fuels mentioned above has been observed over a period of 30 years at discrete time intervals, δt = 30 days. In the case of UF₄,M values atDR = 200 cm reach 5·35, 5·22,4·88, and 4·88 from 3·12, 2·98, 2·83 and 2·83, for 25,50,75,100% flibe respectively. For ThF₄ atDR = 50 cm,M values reach from 1·61, 1·54, 1·50 and 1·46 to 1·93, 2·00, 2·04 and 1·99 for 25, 50, 75, 100% flibe respectively. Cumulative fissile fuel breeding (CFFE) values reach up to 5·5 from 0·7 atDR = 200 and 25% case for UF₄, and up to 6·36% from 0%, atDR = 50 and 25% flibe, for ThF₄, at the end of the operation period