To enhance interfacial bonding between carbon fibers and epoxy matrix, the carbon fibers have been modified with multiwall carbon nanotubes (MWCNTs) using the dip- coating technique. FT-IR spectrum of the MWCNTs shows a peak at 1640 cm−1 corresponding to the stretching mode of the C=C double bond which forms the framework of the carbon nanotube sidewall. The broad peak at 3430 cm−1 is due to O–H stretching vibration of hydroxyl groups and the peak at 1712 cm−1 corresponds to the carboxylic (C=O) group attached to the carbon fiber. The peaks at 2927 cm−1 and 2862 cm−1 are assigned to C–H stretching vibration of epoxy produced at the defect sites of acid-oxidized carbon fiber surface. SEM image shows a better interface bonding between the fiber and the matrix of modified composites (MWCNTs-CF/Ep) than those of unmodified composite. The loss factor curve of CF-MWCNTs/Ep composites is the narrowest compared with neat epoxy and CF/Ep composites which evinces that the length distribution range of molecular chain segments in the matrix is the narrowest. From the dependence of the AC conductivity on temperature, we can see that σAC increases when temperature increases. The increase in electrical conductivity of the composites may be a result of the increased chain ordering due to annealing effect. The use of MWCNTs to modify the surface of carbon fiber resulted in a large amount of junctions among MWCNT causing an increase in the electrical and thermal conductivity by forming conducting paths in the matrix. The MWCNTs-CF/Ep composite shows better thermal stability than unmodified composites. The strong interaction between CF and MWCNTs can retard diffusion of small molecules from the resin matrix at high temperature and hence, result in the improved thermal stability of the modified CF/Ep composite.
Erratum for Organic acid concentration thresholds for ageing of carbonate minerals: Implications for CO2 trapping/storage.
It highlights the importance of research through its focus on the assessment of tax for settling accounts Mmakhr medicines and annual statement controls and its role in determining the taxable income of the real tax Mmakhr drugs and achieve tax equity through tax settling accounts. The tax authority relies annual controls laid down by the tax settling accounts for Mmakhr medicines despite their inclusion bookkeeping business No. 2 system for the year 1985 average .ually this basis formulated hypothesis (that the adoption of the tax authority on annual controls in the tax settling accounts for Mmakhr medicine does not contribute in determining income taxable real tax for this Almmakr). the resulting search for a number of conclusions and
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This Research aims for harnessing critical and innovative thinking approaches besides innovative problem solving tools in pursuing continual quality improvement initiatives for the benefit of achieving operations results effectively in water treatment plants in Baghdad Water Authority. Case study has been used in fulfilling this research in the sadr city water treatment plant, which was chosen as a study sample as it facilitates describing and analyzing its current operational situation, collecting and analyzing its own data, in order to get its own desired improvement opportunity be done. Many statistical means and visual thinking promoting methods has been used to fulfill research task.
... Show MoreEscherichia coli (E. coli) is a frequent gram-negative bacterium that causes nosocomial infections, affecting more than 100 million patients annually worldwide. Bacterial lipopolysaccharide (LPS) from E. coli binds to toll-like receptor 4 (TLR4) and its co-receptor’s cluster of differentiation protein 14 (CD14) and myeloid differentiation factor 2 (MD2), collectively known as the LPS receptor complex. LPCAT2 participates in lipid-raft assembly by phospholipid remodelling. Previous research has proven that LPCAT2 co-localises in lipid rafts with TLR4 and regulates macrophage inflammatory response. However, no published evidence exists of the influence of LPCAT2 on the gene expression of the LPS receptor complex induced by smooth or rough b
... Show MoreThis study focused on a fundamental issue which was represented by ability of Iraqi central bank in facing the difficulty of determining the optimal ratio of liquidity in the Iraqi banks in terms of the balancing between its obligations to the depositors and borrowers, and liquidate their funds on one hand and the risks on the other hand.the search aimed for achieving the goals which represented by identifying the possibility of Iraqi banks to apply the regulations rules and instructions issued by central bank of Iraq in determining ratio of liquidity and its appropriate with Iraqi banks action to implement a reasonable profit to&
... Show MoreGod Almighty put in his great book secrets that do not end, and wonders that do not expire, for he is the one from which the scholars are not satisfied, and he does not create due to the multitude of response, and it is the comprehensive and inhibitory book that God conceals to the worlds, and he challenged the two heavyweights to come up with something like it.
At all times, issues arise in the Noble Qur’an that fit the needs of the people of that time and their culture, for it is an eternal book, characterized by the ability to give, extend and respond to addressing the problems of the age and its variables, when the Arabs had little luck at the time of the message’s descent from the scientific culture, and their proficienc
... Show MoreThe title compound was synthesized by 2:1 condensation between adamantan-1-ylamine and benzene-1,4- dicarbaldehyde in n-BuOH and produced a good yield 87% of new bis Schiff base. The compound skeleton was affirmed by FTIR, 1H NMR, LC-MS, and X-ray powder diffraction. The structure was solved by a parallel tempering process and refined by using Rietveld refinement. Two adamantan-1-ylimino groups are connected in the anti-positions to the planar central 1,4-dimethylbenzene group. All rings of the adamantyl group possess normal chair conformation.
This study depicts the removal of Manganese ions (Mn2+) from simulated wastewater by combined electrocoagulation/ electroflotation technologies. The effects of initial Mn concentration, current density (C.D.), electrolysis time, and different mesh numbers of stainless steel screen electrodes were investigated in a batch cell by adopting Taguchi experimental design to explore the optimum conditions for maximum removal efficiency of Mn. The results of multiple regression and signal to noise ratio (S/N) showed that the optimum conditions were Mn initial concentration of 100 ppm, C.D. of 4 mA/cm2, time of 120 min, and mesh no. of 30 (wire/inch). Also, the relative significance of each factor was attained by the analysis of variance (ANO
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