Developing magnetic functionalized multi-walled carbon nanotubes-based buckypaper for the removal of Furazolid

Magnetic f-MWCNTs-based BP/PVA membrane was fabricated and utilized for the elimination of furazolidone (FZD) from aqueous solution. Characterisation and adsorption studies were performed to evaluate the performance and adsorptive efficiency, respectively of the membrane. Furthermore, statistical and machine learning technique were also applied to predict the removal efficiency of FZD on the membrane. The results revealed that magnetic f-MWCNTs-based BP/PVA membrane has the potential to be used as an efficient membrane for practical applications

New inorganic nanomaterials for low-voltage transistor applications

This research aims to synthesise and characterise solution-processable high-k dielectric nanorods, which are potentially suitable for use as the dielectric layer in low-voltage Organic Field-Effect Transistor (OFET) applications. Oleic acid-stabilised titanium dioxide nanorods (TiO₂-OA), metal-doped anatase titanium oxide (TiO₂-OA-M; M=Nb, In, or Nb/In) nanorods, rutile titanium oxide nanorods (TiO₂) and barium titanium oxide nanorods (BaTiO₃) have been prepared and investigated.Solution processable oleic acid-stabilised titanium dioxide nanorods (TiO₂-OA) have been prepared by hydrolysis of titanium (IV) tetraisopropoxide (TTIP) with oleic acid (OA) as surfactant in the presence of trimethylamine N-oxide (TMAO). Furthermore, a series of ligand exchange reactions were carried out to replace the oleic acid bonded on the surface of TiO₂-OA with diethyl 2-phenylethyl phosphonate (DEPPNA), octadecylphosphonic acid (ODPA) or octylphosphonic acid (OPA). The ligand exchange rate was characterised by a combination of 31P liquid NMR, ICP, CHN, and FT-IR. The solubility of the ligand-exchanged products in chlorobenzene was also investigated.A novel method based on the co-hydrolysis of titanium (IV) tetraisopropoxide (TTIP) and niobium or/and indium isopropoxide or ethoxide has been investigated to prepare solution-processable, oleic acid- stabilised, niobium- and indium-doped, anatase TiO₂ nanorods (TiO₂-OA-M; M = Nb, In or Nb/In). The effect of niobium and indium precursors, the molar ratio of Nb or In precursors/TTIP and reaction time on the composition, structure and morphology of the Nb or In doped TiO₂ products have been investigated by a combination of XPS, XRD, ICP, CHN, FT-IR and TEM. Furthermore, a series of ligand exchange reactions were carried out to replace the oleic acid, which is bonded on the surface of TiO₂-OA-M, with diethyl 2-phenylethyl phosphonate (DEPPNA) or octadecylphosphonic acid (ODPA). The solubility of the products in chlorobenzene was also investigated.Rutile titanium dioxide nanorods with different sizes were prepared by three different approaches. In the first approach，hair-like rutile nanorods TiO₂ were prepared by simple hydrolysis of a TiOCl₂ solution at low temperature (50, 70 and 90 °C). In the second approach, rutile nanorods TiO₂ with a length of 150-200 nm and a width of 25-40 nm were prepared by using a hydrothermal treatment of TiOCl₂ at 220 °C. In the third approach, rutile nanorods TiO₂ with length of 80 nm and diameter of 20 nm were prepared by using an hydrothermal reaction of TiOCl₂ in the presence of 3-hydroxytyramine hydrogen chloride, [(HO)₂C₆H₃CH₂CH₂NH₂·HCl] at 150°C. In order to improve the solubility of the obtained rutile titanium dioxide nanorods in organic solvents, different surface-modification methods have been investigated to coat the surface of the rutile titanium dioxide nanorods with various organic ligands. In the first method, a modification of the TiO₂ nanorods with oleic acid (OA) in chlorobenzene was investigated. In the second method, a two-stage treatment of TiO₂ nanorods in an acidic medium was studied, using a selection of oleic acid (OA), diethyl 2-phenylethyl phosphonate (DEPPNA), octylphosphonic acid (OPA) and decylphosphonic acid (ODPA) as ligands. In the third method, wet TiO₂ nanorods before dry was directly modified with a range of oleic acid and amines, e.g., octylamine, dodecylamine and hexadecylamine, as ligands. All the products were characterized by a combination of XRD, ICP, CHN, FT-IR and TEM.The preparation of barium titanium oxide nanorods (BaTiO₃) has been investigated by different approaches. In the first approach, a hydrothermal reaction was carried out to convert the titanium dioxide nanorods prepared in the first and third parts in this research into BaTiO₃ nanorods. The effect of the molar ratio of Ba/Ti, the reaction pH, reaction time and temperature on the composition, structure and morphology of the products were fully investigated. In the second approach, a hydrothermal reaction using a single source Ba/Ti precursor, i.e., barium titanium ethylhexano-isoproxide BaTi(O₂CC₇H₁₅)(OC₃H₇)₅, was carried out to prepare barium titanium oxide nanorods. In the third approach, barium titanium oxide nanorods were prepared by using a hydrothermal reaction between barium chloride (BaCl₂) and titanium oxy chloride (TiOCl₂) in the presence of ethylene glycol as surfactant. All the products have been characterised by a combination of XRD, ICP, CHN, FT-IR and TEM

SOCIALLY RESPONSIBLE CONSUMER BEHAVIOR IN THE STATE OF QATAR

Every single consumption choice that consumers make has an impact on the society and on the environment. By choosing products that have a limited impact on the environment and the society consumers can help saving the environment and help in having a sustainable resources, thus bring the changes they want in the marketplace. The purpose of this research paper is to identify what people in Qatar include in the concept of responsible consumption, with regard to many choices, and which are the responsibilities they think they have as responsible consumers. A questioner was developed and distributed to different category of the society to measure their social responsible consumer behavior. A total of 129 respond has been collected. The paper has concluded that there is no relation between different consumer groups and their social consumer behavior. The consumers in Qatar do not have much awareness in that filed due to many reasons. Society wealth, lack of awareness from the government and the social responsible culture might be some of reasons for that problem

Upgrading Biological Treatment of Wastewater at Dubai’s Plant by a Fixed-Film System

The wastewater treatment plant in Dubai, with a design capacity of 130,000 m3/d, receives primarily domestic wastewater and employs primary, secondary and tertiary stages of treatment to produce an effluent suitable for reuse in irrigation. Performance of the plant is influenced to a great extent by the success of the secondary aerobic biological treatment stage. This stage comprises the high-rate activated sludge system for removal of carbonaceous organics followed by the biofilter system for removal of nitrogenous material by nitrification. Operational problems have often been experienced at this plant because of increasing sludge solids production and sludge rising in the high-rate activated sludge system, which in turn overload the sludge treatment facilities and the biological filter system. This study aimed at upgrading the existing biological treatment system in an attempt to improve process performance and overcome operational problems. An innovative biological system, the aerated submerged fixed-film (ASFF) process which employs a four compartment-in-series reactor with an array of fixed ceramic plates, has been examined for this purpose. The study involved field testing and chemical analyses of a pilot-scale ASFF bioreactor in a series of experiments on the ASFF reactor in parallel with the existing activated sludge and biofilter systems. Performance of the ASFF process was examined at different hydraulic retention times (HRT\u27s) and loading conditions. The results obtained demonstrated the feasibility of upgrading the existing facilities by the ASFF process. Analysis of performance data indicated comparable results at short HRT\u27s of 2 hours and considerably better results from the ASFF at longer HRT\u27s of 6-8 hours. The ASFF process has an advantage of combining the removal of both carbonaceous and nitrogenous materials in one system rather than in two systems as practiced in the existing facilities. This process requires less space and produces minimal sludge solids quantities, thus reducing the treatment costs. It will provide an adequate treatment that does not suffer from the rising sludge problem and can easily cope with overloading as long as sufficient aeration is provided. The process can be easily implemented in the aeration tanks of the existing activated-sludge system by fixing an array of locally-made ceramic plates which will also eliminate the need for biofilters. A mathematical model was adopted to describe process kinetics and to design the upgraded system

Language Learning Strategies Among Saudi EFL Students

This study aims to examine language learning strategies as important factors that affect students’ learning. The study sample consists of 34 male students in Royal Guard Secondary School in Riyadh city. In order to examine the English language learning strategy, use among Saudi secondary-school EFL students, they provided their responses to Oxford’s Strategy Inventory for Language Learning (SILL) (Oxford 1990, Version 7.0). The results showed that the students used direct strategies more than indirect strategies. The most frequently used strategies among students were compensation strategies, whereas the least frequently used strategies were social strategies. In addition, the study results show that the general pattern of language learning strategy used by the students includes compensation, affective, metacognitive, cognitive, memory, and finally social strategy. It can be concluded that teachers in secondary-schools are recommended to pay due attention to the use of language learning strategies among students and support them in employing the strategies that are beneficial for them based on the differences and styles. This can help teachers greatly in achieving satisfactory teaching results. Keywords: Learning Strategies, Memory Strategies, Cognitive Strategies, Compensation Strategies, Metacognitive Strategies, Affective Strategies, Social Strategies